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Collins HE, Alexander BT, Care AS, Davenport MH, Davidge ST, Eghbali M, Giussani DA, Hoes MF, Julian CG, LaVoie HA, Olfert IM, Ozanne SE, Bytautiene Prewit E, Warrington JP, Zhang L, Goulopoulou S. Guidelines for assessing maternal cardiovascular physiology during pregnancy and postpartum. Am J Physiol Heart Circ Physiol 2024; 327:H191-H220. [PMID: 38758127 DOI: 10.1152/ajpheart.00055.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 04/22/2024] [Accepted: 05/08/2024] [Indexed: 05/18/2024]
Abstract
Maternal mortality rates are at an all-time high across the world and are set to increase in subsequent years. Cardiovascular disease is the leading cause of death during pregnancy and postpartum, especially in the United States. Therefore, understanding the physiological changes in the cardiovascular system during normal pregnancy is necessary to understand disease-related pathology. Significant systemic and cardiovascular physiological changes occur during pregnancy that are essential for supporting the maternal-fetal dyad. The physiological impact of pregnancy on the cardiovascular system has been examined in both experimental animal models and in humans. However, there is a continued need in this field of study to provide increased rigor and reproducibility. Therefore, these guidelines aim to provide information regarding best practices and recommendations to accurately and rigorously measure cardiovascular physiology during normal and cardiovascular disease-complicated pregnancies in human and animal models.
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Grants
- HL169157 HHS | NIH | National Heart, Lung, and Blood Institute (NHLBI)
- HD083132 HHS | NIH | Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
- Jewish Heritage Fund for Excellence
- The Biotechnology and Biological Sciences Research Council
- P20GM103499 HHS | NIH | National Institute of General Medical Sciences (NIGMS)
- Distinguished University Professor
- HL146562 HHS | NIH | National Heart, Lung, and Blood Institute (NHLBI)
- The Lister Insititute
- ES032920 HHS | NIH | National Institute of Environmental Health Sciences (NIEHS)
- Canadian Insitute's of Health Research Foundation Grant
- HL149608 HHS | NIH | National Heart, Lung, and Blood Institute (NHLBI)
- Christenson professor In Active Healthy Living
- Royal Society (The Royal Society)
- U.S. Department of Defense (DOD)
- HL138181 HHS | NIH | National Heart, Lung, and Blood Institute (NHLBI)
- MC_00014/4 UKRI | Medical Research Council (MRC)
- HD111908 HHS | NIH | Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
- HL163003 HHS | NIH | National Heart, Lung, and Blood Institute (NHLBI)
- APP2002129 NHMRC Ideas Grant
- HL159865 HHS | NIH | National Heart, Lung, and Blood Institute (NHLBI)
- British Heart Foundation (BHF)
- HL131182 HHS | NIH | National Heart, Lung, and Blood Institute (NHLBI)
- HL163818 HHS | NIH | National Heart, Lung, and Blood Institute (NHLBI)
- NS103017 HHS | NIH | National Institute of Neurological Disorders and Stroke (NINDS)
- HL143459 HHS | NIH | National Heart, Lung, and Blood Institute (NHLBI)
- 20CSA35320107 American Heart Association (AHA)
- RG/17/12/33167 British Heart Foundation (BHF)
- National Heart Foundation Future Leader Fellowship
- P20GM121334 HHS | NIH | National Institute of General Medical Sciences (NIGMS)
- HL146562-04S1 HHS | NIH | National Heart, Lung, and Blood Institute (NHLBI)
- HL155295 HHS | NIH | National Heart, Lung, and Blood Institute (NHLBI)
- HD088590-06 HHS | NIH | Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
- HL147844 HHS | NIH | National Heart, Lung, and Blood Institute (NHLBI)
- WVU SOM Synergy Grant
- R01 HL146562 NHLBI NIH HHS
- HL159447 HHS | NIH | National Heart, Lung, and Blood Institute (NHLBI)
- ES034646-01 HHS | NIH | National Institute of Environmental Health Sciences (NIEHS)
- HL150472 HHS | NIH | National Heart, Lung, and Blood Institute (NHLBI)
- 2021T017 Dutch Heart Foundation Dekker Grant
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Affiliation(s)
- Helen E Collins
- University of Louisville, Louisville, Kentucky, United States
| | - Barbara T Alexander
- University of Mississippi Medical Center, Jackson, Mississippi, United States
| | - Alison S Care
- University of Adelaide, Adelaide, South Australia, Australia
| | | | | | - Mansoureh Eghbali
- University of California Los Angeles, Los Angeles, California, United States
| | | | | | - Colleen G Julian
- University of Colorado School of Medicine, Aurora, Colorado, United States
| | - Holly A LaVoie
- University of South Carolina School of Medicine, Columbia, South Carolina, United States
| | - I Mark Olfert
- West Virginia University School of Medicine, Morgantown, West Virginia, United States
| | | | | | - Junie P Warrington
- University of Mississippi Medical Center, Jackson, Mississippi, United States
| | - Lubo Zhang
- Loma Linda University School of Medicine, Loma Linda, California, United States
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Brown ER, Giussani DA. Cause of fetal growth restriction during high-altitude pregnancy. iScience 2024; 27:109702. [PMID: 38694168 PMCID: PMC11061758 DOI: 10.1016/j.isci.2024.109702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 02/23/2024] [Accepted: 04/05/2024] [Indexed: 05/04/2024] Open
Abstract
High-altitude pregnancy increases the incidence of fetal growth restriction and reduces birth weight. This poses a significant clinical challenge as both are linked to adverse health outcomes, including raised infant mortality and the development of the metabolic syndrome in later life. While this reduction in birth weight is mostly understood to be driven by the hypobaric hypoxia of high altitude, the causative mechanism is unclear. Moreover, it is now recognized that highland ancestry confers protection against this reduction in birth weight. Here, we analyze the evidence that pregnancy at high altitude reduces birth weight and that highland ancestry confers protection, discussing mechanisms contributing to both effects.
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Affiliation(s)
- Emily R. Brown
- Department of Physiology, Development & Neuroscience, University of Cambridge, Cambridge, UK
| | - Dino A. Giussani
- Department of Physiology, Development & Neuroscience, University of Cambridge, Cambridge, UK
- Centre for Trophoblast Research, University of Cambridge, Cambridge, UK
- Cambridge Strategic Research Initiative in Reproduction
- Cambridge Cardiovascular Centre for Research Excellence
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Duko B, Gebremedhin AT, Tessema GA, Dunne J, Alati R, Pereira G. The effects of pre-eclampsia on social and emotional developmental vulnerability in children at age five in Western Australia: A population data linkage study. J Affect Disord 2024; 352:349-356. [PMID: 38360367 DOI: 10.1016/j.jad.2024.02.042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 02/07/2024] [Accepted: 02/12/2024] [Indexed: 02/17/2024]
Abstract
BACKGROUND It is important to explore factors that may hinder early childhood development in AEDC Emotional Maturity and Social Competence domains as these underpin the foundation for health, well-being, and productivity over the life course. No previous study has examined whether, or to what extent, preeclampsia increases the risk of developmental vulnerability in social and emotional domains in early childhood. METHODS We conducted a retrospective population-based cohort study on the association between preeclampsia and childhood developmental vulnerability in emotional maturity and social competence domains in children born in Western Australia in 2009, 2012 and 2015. We obtained records of births, developmental anomalies, midwives notifications and hospitalisations. These data were linked to the Australian Early Development Census (AEDC), from which developmental vulnerability in emotional maturity and social competence domains at a median age of 5 years was ascertained. Causal relative risks (RR) were estimated with doubly robust estimation. RESULTS A total of 64,391 mother-offspring pairs were included in the final analysis. For the whole cohort, approximately 25 % and 23 % of children were classified as developmentally vulnerable or at-risk on AEDC emotional maturity and social competence domains, respectively. Approximately 2.8 % of children were exposed in utero to preeclampsia. Children exposed to preeclampsia were more likely to be classified as developmentally vulnerable or at-risk on the emotional maturity (RR = 1.19, 95%CI:1.11-1.28) and social competence domains (RR = 1.22, 95 % CI:1.13-1.31). CONCLUSION Children exposed to pre-eclampsia in utero were more likely to be developmentally vulnerable in emotional maturity and social competence domains in this cohort. Our findings provide new insights into the harmful effect of preeclampsia on childhood developmental vulnerability.
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Affiliation(s)
- Bereket Duko
- Australian Centre for Precision Health, UniSA Clinical & Health Sciences, University of South Australia, Adelaide, SA 5000, Australia; Curtin School of Population Health, Curtin University, Kent St, Bentley, WA 6102, Australia; South Australian Health and Medical Research Institute, Adelaide, SA 5000, Australia.
| | | | - Gizachew Assefa Tessema
- Curtin School of Population Health, Curtin University, Kent St, Bentley, WA 6102, Australia; enAble Institute, Curtin University, Kent Street, Bentley, Western Australia 6102, Australia
| | - Jennifer Dunne
- Curtin School of Population Health, Curtin University, Kent St, Bentley, WA 6102, Australia
| | - Rosa Alati
- Curtin School of Population Health, Curtin University, Kent St, Bentley, WA 6102, Australia; enAble Institute, Curtin University, Kent Street, Bentley, Western Australia 6102, Australia; Institute for Social Sciences Research, The University of Queensland, 80 Meier's Rd, Indooroopilly, Queensland 4068, Australia
| | - Gavin Pereira
- Curtin School of Population Health, Curtin University, Kent St, Bentley, WA 6102, Australia; enAble Institute, Curtin University, Kent Street, Bentley, Western Australia 6102, Australia
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Heath-Freudenthal A, Estrada A, von Alvensleben I, Julian CG. Surviving birth at high altitude. J Physiol 2024. [PMID: 38520695 DOI: 10.1113/jp284554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 03/11/2024] [Indexed: 03/25/2024] Open
Abstract
This Symposium Review examines challenges to surviving birth and infancy at high altitudes. Chronic exposure to the environmental hypoxia of high altitudes increases the incidence of maternal vascular disorders of pregnancy characterized by placental insufficiency, restricted fetal growth and preterm delivery, and impairs pulmonary vascular health during infancy. While each condition independently contributes to excess morbidity and mortality in early life, evidence indicates vascular disorders of pregnancy and infantile pulmonary vascular dysfunction are intertwined. By integrating our recent scientific and clinical observations in Bolivia with existing literature, we propose potential avenues to reduce the infant mortality burden at high altitudes and reduce pulmonary vascular disease in highland neonates, and emphasize the need for further research to address unresolved questions.
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Affiliation(s)
| | | | | | - Colleen G Julian
- Department of Biomedical Informatics, University of Colorado School of Medicine, Aurora, Colorado, USA
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Song J, Yuan L, Hua W, Guojuan C, Shaoyu C. Comparison of ET-1 and eNOS expressions in yak testes at different developmental stages. Reprod Domest Anim 2023; 58:1542-1550. [PMID: 37724684 DOI: 10.1111/rda.14469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Revised: 08/14/2023] [Accepted: 08/26/2023] [Indexed: 09/21/2023]
Abstract
Yak has strong adaptability to plateau hypoxia environment. However, the endothelin-1 (ET-1) and endothelial nitric oxide synthase (eNOS) are important regulators in blood oxygen transportation. Yak testes: newborn (3 days), young (1 years), adult (4 years) and old (9 years) were collected for microscopic analyses using haematoxylin and eosin staining (H&E), immunohistochemistry and immunofluorescence, as well as Western blot to compare the expression of ET-1 and eNOS. Furthermore, the levels of ET-1 mRNA and eNOS mRNA was detected by real-time quantitative polymerase chain reaction (RT-qPCR). The results showed that ET-1 mRNA and eNOS mRNA in old yaks were higher than other developmental stages (p < .01). And the levels of ET-1 and eNOS protein increased with age. Immunohistochemistry and immunofluorescence showed that ET-1 and eNOS were mainly localized in gonocytes and spermatogenic membrane of newborn yaks. These two factors were expressed in both Leydig cells of young yaks and endothelial cells of adult yaks. In old yaks, ET-1 was mainly expressed in Sertoli cells, while eNOS was obviously positive in capillaries and Leydig cells. Therefore, the positive results of ET-1 and eNOS in gonocyte and spermatogenic basement were closely related to the development of testes. The expression of Leydig and Sertoli cells indicated that they played an important role in testes function. The expression in endothelial cells or interstitial capillaries, suggesting that they are involved in the regulation of microcirculation in yak testes. This study could provide clues for further revealing the regulation of yak testicular blood vessels in alpine cold and hypoxic environments.
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Affiliation(s)
- Juanjuan Song
- College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China
- Key Laboratory of Animal Reproductive Physiology and Reproductive Regulation of Gansu Province, Lanzhou, China
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Ligang Yuan
- College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China
- Key Laboratory of Animal Reproductive Physiology and Reproductive Regulation of Gansu Province, Lanzhou, China
| | - Wang Hua
- College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China
- Key Laboratory of Animal Reproductive Physiology and Reproductive Regulation of Gansu Province, Lanzhou, China
| | - Chen Guojuan
- College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China
- Key Laboratory of Animal Reproductive Physiology and Reproductive Regulation of Gansu Province, Lanzhou, China
| | - Chen Shaoyu
- College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China
- Key Laboratory of Animal Reproductive Physiology and Reproductive Regulation of Gansu Province, Lanzhou, China
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Dangudubiyyam SV, Bosse B, Yadav P, Song R, Hofmann A, Mishra JS, Kumar S. Restoring Angiotensin Type 2 Receptor Function Reverses PFOS-Induced Vascular Hyper-Reactivity and Hypertension in Pregnancy. Int J Mol Sci 2023; 24:14180. [PMID: 37762482 PMCID: PMC10531530 DOI: 10.3390/ijms241814180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 09/07/2023] [Accepted: 09/15/2023] [Indexed: 09/29/2023] Open
Abstract
Perfluorooctane sulfonic acid (PFOS) exposure during pregnancy induces hypertension with decreased vasodilatory angiotensin type-2 receptor (AT2R) expression and impaired vascular reactivity and fetal weights. We hypothesized that AT2R activation restores the AT1R/AT2R balance and reverses gestational hypertension by improving vascular mechanisms. Pregnant Sprague-Dawley rats were exposed to PFOS through drinking water (50 μg/mL) from gestation day (GD) 4-20. Controls received drinking water with no detectable PFOS. Control and PFOS-exposed rats were treated with AT2R agonist Compound 21 (C21; 0.3 mg/kg/day, SC) from GD 15-20. In PFOS dams, blood pressure was higher, blood flow in the uterine artery was reduced, and C21 reversed these to control levels. C21 mitigated the heightened contraction response to Ang II and enhanced endothelium-dependent vasorelaxation in uterine arteries of PFOS dams. The observed vascular effects of C21 were correlated with reduced AT1R levels and increased AT2R and eNOS protein levels. C21 also increased plasma bradykinin production in PFOS dams and attenuated the fetoplacental growth restriction. These data suggest that C21 improves the PFOS-induced maternal vascular dysfunction and blood flow to the fetoplacental unit, providing preclinical evidence to support that AT2R activation may be an important target for preventing or treating PFOS-induced adverse maternal and fetal outcomes.
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Affiliation(s)
- Sri Vidya Dangudubiyyam
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA; (S.V.D.); (P.Y.); (R.S.); (A.H.); (J.S.M.)
- Endocrinology-Reproductive Physiology Program, University of Wisconsin, Madison, WI 53715, USA
| | - Bradley Bosse
- Department of Obstetrics and Gynecology, School of Medicine and Public Health, University of Wisconsin, Madison, WI 53792, USA;
| | - Pankaj Yadav
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA; (S.V.D.); (P.Y.); (R.S.); (A.H.); (J.S.M.)
| | - Ruolin Song
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA; (S.V.D.); (P.Y.); (R.S.); (A.H.); (J.S.M.)
| | - Alissa Hofmann
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA; (S.V.D.); (P.Y.); (R.S.); (A.H.); (J.S.M.)
- Endocrinology-Reproductive Physiology Program, University of Wisconsin, Madison, WI 53715, USA
| | - Jay S. Mishra
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA; (S.V.D.); (P.Y.); (R.S.); (A.H.); (J.S.M.)
| | - Sathish Kumar
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA; (S.V.D.); (P.Y.); (R.S.); (A.H.); (J.S.M.)
- Endocrinology-Reproductive Physiology Program, University of Wisconsin, Madison, WI 53715, USA
- Department of Obstetrics and Gynecology, School of Medicine and Public Health, University of Wisconsin, Madison, WI 53792, USA;
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7
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Julian CG, Houck JA, Fallahi S, Lazo-Vega L, Matarazzo CJ, Diamond B, Miranda-Garrido V, Krause BJ, Moore LG, Shortt JA, Toledo-Jaldin L, Lorca RA. Altered placental ion channel gene expression in preeclamptic high-altitude pregnancies. Physiol Genomics 2023; 55:357-367. [PMID: 37458464 PMCID: PMC10642922 DOI: 10.1152/physiolgenomics.00013.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 06/12/2023] [Accepted: 07/06/2023] [Indexed: 08/12/2023] Open
Abstract
High-altitude (>2,500 m) residence increases the risk of pregnancy vascular disorders such as fetal growth restriction and preeclampsia, each characterized by impaired placental function. Genetic attributes of highland ancestry confer relative protection against vascular disorders of pregnancy at high altitudes. Although ion channels have been implicated in placental function regulation, neither their expression in high-altitude placentas nor their relationship to high-altitude preeclampsia has been determined. Here, we measured the expression of 26 ion-channel genes in placentas from preeclampsia cases and normotensive controls in La Paz, Bolivia (3,850 m). In addition, we correlated gene transcription to maternal and infant ancestry proportions. Gene expression was assessed by PCR, genetic ancestry evaluated by ADMIXTURE, and ion channel proteins localized by immunofluorescence. In preeclamptic placentas, 11 genes were downregulated (ABCC9, ATP2A2, CACNA1C, KCNE1, KCNJ8, KCNK3, KCNMA1, KCNQ1, KCNQ4, PKD2, and TRPV6) and two were upregulated (KCNQ3 and SCNN1G). KCNE1 expression was positively correlated with high-altitude Amerindian ancestry and negatively correlated with non-high altitude. SCNN1G was negatively correlated with African ancestry, despite minimal African admixture. Most ion channels were localized in syncytiotrophoblasts (Cav1.2, TRPP2, TRPV6, and Kv7.1), whereas expression of Kv7.4 was primarily in microvillous membranes, Kir6.1 in chorionic plate and fetal vessels, and MinK in stromal cells. Our findings suggest a role for differential placental ion channel expression in the development of preeclampsia. Functional studies are needed to determine processes affected by these ion channels in the placenta and whether therapies directed at modulating their activity could influence the onset or severity of preeclampsia.
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Affiliation(s)
- Colleen G Julian
- Department of Biomedical Informatics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - Julie A Houck
- Department of Biomedical Informatics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - Sahand Fallahi
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - Litzi Lazo-Vega
- Department of Obstetrics and Gynecology, Hospital Materno-Infantil, La Paz, Bolivia
| | - Christopher J Matarazzo
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - Breea Diamond
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | | | - Bernardo J Krause
- Instituto de Ciencias de la Salud, Universidad de O'Higgins, Rancagua, Chile
| | - Lorna G Moore
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - Jonathan A Shortt
- Department of Biomedical Informatics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - Lilian Toledo-Jaldin
- Department of Obstetrics and Gynecology, Hospital Materno-Infantil, La Paz, Bolivia
| | - Ramón A Lorca
- Department of Obstetrics and Gynecology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
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8
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Ca 2+-Activated K + Channels and the Regulation of the Uteroplacental Circulation. Int J Mol Sci 2023; 24:ijms24021349. [PMID: 36674858 PMCID: PMC9867535 DOI: 10.3390/ijms24021349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 01/06/2023] [Accepted: 01/08/2023] [Indexed: 01/13/2023] Open
Abstract
Adequate uteroplacental blood supply is essential for the development and growth of the placenta and fetus during pregnancy. Aberrant uteroplacental perfusion is associated with pregnancy complications such as preeclampsia, fetal growth restriction (FGR), and gestational diabetes. The regulation of uteroplacental blood flow is thus vital to the well-being of the mother and fetus. Ca2+-activated K+ (KCa) channels of small, intermediate, and large conductance participate in setting and regulating the resting membrane potential of vascular smooth muscle cells (VSMCs) and endothelial cells (ECs) and play a critical role in controlling vascular tone and blood pressure. KCa channels are important mediators of estrogen/pregnancy-induced adaptive changes in the uteroplacental circulation. Activation of the channels hyperpolarizes uteroplacental VSMCs/ECs, leading to attenuated vascular tone, blunted vasopressor responses, and increased uteroplacental blood flow. However, the regulation of uteroplacental vascular function by KCa channels is compromised in pregnancy complications. This review intends to provide a comprehensive overview of roles of KCa channels in the regulation of the uteroplacental circulation under physiological and pathophysiological conditions.
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Mundo W, Toledo-Jaldin L, Heath-Freudenthal A, Huayacho J, Lazo-Vega L, Larrea-Alvarado A, Miranda-Garrido V, Mizutani R, Moore LG, Moreno-Aramayo A, Gomez R, Gutierrez P, Julian CG. Is Maternal Cardiovascular Performance Impaired in Altitude-Associated Fetal Growth Restriction? High Alt Med Biol 2022; 23:352-360. [PMID: 36472463 DOI: 10.1089/ham.2022.0082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Mundo, William, Lilian Toledo-Jaldin, Alexandrea Heath-Freudenthal, Jaime Huayacho, Litzi Lazo-Vega, Alison Larrea-Alvarado, Valquiria Miranda-Garrido, Rodrigo Mizutani, Lorna G. Moore, Any Moreno-Aramayo, Richard Gomez, Patricio Gutierrez, and Colleen G. Julian. Is maternal cardiovascular performance impaired in altitude-associated fetal growth restriction? High Alt Med Biol. 23:352-360, 2022. Introduction: The incidence of fetal growth restriction (FGR) is elevated in high-altitude resident populations. This study aims to determine whether maternal central hemodynamics during the last trimester of pregnancy are altered in high-altitude FGR. Methods: In this cross-sectional study of maternal-infant pairs (FGR, n = 27; controls, n = 26) residing in La Paz, Bolivia, maternal heart rate, cardiac output (CO), stroke volume, and systemic vascular resistance (SVR) were assessed using continuous-wave Doppler ultrasound. Transabdominal Doppler ultrasound was used for uterine artery (UtA) resistance indices and fetal measures. Maternal venous soluble fms-like tyrosine kinase-1 (sFlt1) levels were measured. Results: FGR pregnancies had reduced CO, elevated SVR and UtA resistance, fetal brain sparing, and increased maternal sFlt1 versus controls. Maternal SVR was positively associated with UtA resistance and inversely associated with middle cerebral artery resistance and birth weight. Maternal sFlt1 was greater in FGR than controls and positively associated with UtA pulsatility index. Women with elevated sFlt1 levels also tended to have lower CO and higher SVR. Conclusion: Noninvasive assessment of maternal cardiovascular function may be an additional method for detecting high-risk pregnancies at high altitudes, thereby informing the need for increased surveillance and appropriate allocation of resources to minimize adverse outcomes.
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Affiliation(s)
- William Mundo
- University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA
| | - Lilian Toledo-Jaldin
- Department of Obstetrics and Gynecology, Hospital Materno-Infantil, La Paz, Bolivia
| | | | - Jaime Huayacho
- Department of Obstetrics and Gynecology, Hospital Materno-Infantil, La Paz, Bolivia
| | - Litzi Lazo-Vega
- Department of Obstetrics and Gynecology, Hospital Materno-Infantil, La Paz, Bolivia
| | | | | | - Rodrigo Mizutani
- Department of Obstetrics and Gynecology, Hospital Materno-Infantil, La Paz, Bolivia
| | - Lorna G Moore
- Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA
| | - Any Moreno-Aramayo
- Department of Obstetrics and Gynecology, Hospital Materno-Infantil, La Paz, Bolivia
| | - Richard Gomez
- Department of Obstetrics and Gynecology, Hospital Materno-Infantil, La Paz, Bolivia
| | - Patricio Gutierrez
- Department of Obstetrics and Gynecology, Hospital Materno-Infantil, La Paz, Bolivia
| | - Colleen G Julian
- Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA.,Department of Medicine, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA
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10
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Fallahi S, Houck JA, Euser AG, Julian CG, Moore LG, Lorca RA. High altitude differentially modulates potassium channel-evoked vasodilatation in pregnant human myometrial arteries. J Physiol 2022; 600:5353-5364. [PMID: 36286320 PMCID: PMC9772154 DOI: 10.1113/jp283741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 10/12/2022] [Indexed: 01/05/2023] Open
Abstract
High-altitude (>2500 m or 8200 ft) residence reduces uterine artery blood flow during pregnancy, contributing to an increased incidence of preeclampsia and intrauterine growth restriction. However, not all pregnancies are affected by the chronic hypoxic conditions of high-altitude residence. K+ channels play important roles in the uterine vascular adaptation to pregnancy, promoting a reduction in myogenic tone and an increase in blood flow. We hypothesized that, in pregnancies with normal fetal growth at high altitude, K+ channel-dependent vasodilatation of myometrial arteries is increased compared to those from healthy pregnant women at a lower altitude (∼1700 m). Using pharmacological modulation of two K+ channels, ATP-sensitive (KATP ) and large-conductance Ca2+ -activated (BKCa ) K+ channels, we assessed the vasodilatation of myometrial arteries from appropriate for gestational age (AGA) pregnancies in women living at high or low altitudes. In addition, we evaluated the localization of these channels in the myometrial arteries using immunofluorescence. Our results showed an endothelium-dependent increase in KATP -dependent vasodilatation in myometrial arteries from high versus low altitude, whereas vasodilatation induced by BKCa activation was reduced in these vessels. Additionally, KATP channel co-localization with endothelial markers was reduced in the high-altitude myometrial arteries, which suggested that the functional increase in KATP activity may be by mechanisms other than regulation of channel localization. These observations highlight an important contribution of K+ channels to the human uterine vascular adaptation to pregnancy at high altitude serving to maintain normal fetal growth under conditions of chronic hypoxia. KEY POINTS: High-altitude (>2500 m or 8200 ft) residence reduces uterine blood flow during pregnancy and fetal growth. Animal models of high altitude/chronic hypoxia suggest that these reductions are partially due to reduced vascular K+. channel responses, such as those elicited by large conductance Ca2+ -activated (BKCa ) and ATP-sensitive (KATP ) K+ channel activation. We found that women residing at high versus low altitude during pregnancy showed diminished myometrial artery vasodilatory responses to endothelium-independent BKCa channel activation but greater responses to endothelium-dependent KATP channel activation. Our observations indicate that KATP channels play an adaptive role in maintaining myometrial artery vasodilator sensitivity under chronic hypoxic conditions during pregnancy. Thus, KATP channels represent potential therapeutic targets for augmenting uteroplacental blood flow and, in turn, preserving fetal growth in cases of uteroplacental hypoperfusion.
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Affiliation(s)
- Sahand Fallahi
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO 80045
| | - Julie A. Houck
- Department of Biomedical Informatics, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO 80045
| | - Anna G. Euser
- Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO 80045
| | - Colleen G. Julian
- Department of Biomedical Informatics, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO 80045
| | - Lorna G. Moore
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO 80045
| | - Ramón A. Lorca
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO 80045
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11
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Moore LG, Wesolowski SR, Lorca RA, Murray AJ, Julian CG. Why is human uterine artery blood flow during pregnancy so high? Am J Physiol Regul Integr Comp Physiol 2022; 323:R694-R699. [PMID: 36094446 PMCID: PMC9602899 DOI: 10.1152/ajpregu.00167.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/12/2022] [Accepted: 09/07/2022] [Indexed: 11/22/2022]
Abstract
In healthy near-term women, blood flow to the uteroplacental circulation is estimated as 841 mL/min, which is greater than in other mammalian species. We argue that as uterine venous Po2 sets the upper limit for O2 diffusion to the fetus, high uterine artery blood flow serves to narrow the maternal arterial-to-uterine venous Po2 gradient and thereby raise uterine vein Po2. In support, we show that the reported levels for uterine artery blood flow agree with what is required to maintain normal fetal growth. Although residence at high altitudes (>2,500 m) depresses fetal growth, not all populations are equally affected; Tibetans and Andeans have higher levels of uterine artery blood flow than newcomers and exhibit normal fetal growth. Estimates of uterine venous Po2 from the umbilical blood-gas data available from healthy Andean pregnancies indicate that their high levels of uterine artery blood flow are consistent with their reported, normal birth weights. Unknown, however, are the effects on placental gas exchange of the lower levels of uterine artery blood flow seen in high-altitude newcomers or hypoxia-associated pregnancy complications. We speculate that, by widening the maternal artery to uterine vein Po2 gradient, lower levels of uterine artery blood flow prompt metabolic changes that slow fetal growth to match O2 supply.
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Affiliation(s)
- Lorna G Moore
- Department of Obstetrics and Gynecology, University of Colorado Denver, Aurora, Colorado
| | | | - Ramón A Lorca
- Department of Obstetrics and Gynecology, University of Colorado Denver, Aurora, Colorado
| | - Andrew J Murray
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Colleen G Julian
- Department of Biomedical Informatics, University of Colorado Denver, Aurora, Colorado
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12
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Chronic High-Altitude Hypoxia Alters Iron and Nitric Oxide Homeostasis in Fetal and Maternal Sheep Blood and Aorta. Antioxidants (Basel) 2022; 11:antiox11091821. [PMID: 36139895 PMCID: PMC9495375 DOI: 10.3390/antiox11091821] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 09/09/2022] [Accepted: 09/12/2022] [Indexed: 11/16/2022] Open
Abstract
The mammalian fetus thrives at oxygen tensions much lower than those of adults. Gestation at high altitude superimposes hypoxic stresses on the fetus resulting in increased erythropoiesis. We hypothesized that chronic hypoxia at high altitude alters the homeostasis of iron and bioactive nitric oxide metabolites (NOx) in gestation. To test for this, electron paramagnetic resonance was used to provide unique measurements of iron, metalloproteins, and free radicals in the blood and aorta of fetal and maternal sheep from either high or low altitudes (3801 or 300 m). Using ozone-based chemiluminescence with selectivity for various NOx species, we determined the NOx levels in these samples immediately after collection. These experiments demonstrated a systemic redistribution of iron in high altitude fetuses as manifested by a decrease in both chelatable and total iron in the aorta and an increase in non-transferrin bound iron and total iron in plasma. Likewise, high altitude altered the redox status diversely in fetal blood and aorta. This study also found significant increases in blood and aortic tissue NOx in fetuses and mothers at high altitude. In addition, gradients in NOx concentrations observed between fetus and mother, umbilical artery and vein, and plasma and RBCs demonstrated complex dynamic homeostasis of NOx among these circulatory compartments, such as placental generation and efflux as well as fetal consumption of iron-nitrosyls in RBCs, probably HbNO. In conclusion, these results may suggest the utilization of iron from non-hematopoietic tissues iron for erythropoiesis in the fetus and increased NO bioavailability in response to chronic hypoxic stress at high altitude during gestation.
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13
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Potassium Channels in the Uterine Vasculature: Role in Healthy and Complicated Pregnancies. Int J Mol Sci 2022; 23:ijms23169446. [PMID: 36012712 PMCID: PMC9409294 DOI: 10.3390/ijms23169446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 08/16/2022] [Accepted: 08/19/2022] [Indexed: 11/28/2022] Open
Abstract
A progressive increase in maternal uterine and placental blood flow must occur during pregnancy to sustain the development of the fetus. Changes in maternal vasculature enable an increased uterine blood flow, placental nutrient and oxygen exchange, and subsequent fetal development. K+ channels are important modulators of vascular function, promoting vasodilation, inducing cell proliferation, and regulating cell signaling. Different types of K+ channels, such as Ca2+-activated, ATP-sensitive, and voltage-gated, have been implicated in the adaptation of maternal vasculature during pregnancy. Conversely, K+ channel dysfunction has been associated with vascular-related complications of pregnancy, including intrauterine growth restriction and pre-eclampsia. In this article, we provide an updated and comprehensive literature review that highlights the relevance of K+ channels as regulators of uterine vascular reactivity and their potential as therapeutic targets.
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14
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Dangudubiyyam SV, Mishra JS, Song R, Kumar S. Maternal PFOS exposure during rat pregnancy causes hypersensitivity to angiotensin II and attenuation of endothelium-dependent vasodilation in the uterine arteries. Biol Reprod 2022; 107:1072-1083. [PMID: 35835584 DOI: 10.1093/biolre/ioac141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 06/21/2022] [Accepted: 07/06/2022] [Indexed: 01/09/2023] Open
Abstract
Epidemiological studies show a strong association between environmental exposure to perfluorooctane sulfonic acid (PFOS) and preeclampsia and fetal growth restriction; however, the underlying mechanisms are unclear. We tested the hypothesis that gestational PFOS exposure leads to pregnancy complications via alterations in uterine vascular endothelium-independent angiotensin II-related mechanisms and endothelium-derived factors such as nitric oxide. Pregnant Sprague Dawley rats were exposed to PFOS 0.005, 0.05, 0.5, 5, 10, and 50 μg/mL through drinking water from gestational day 4 to 20, and dams with PFOS 50 μg/mL were used to assess mechanisms. PFOS exposure dose-dependently increased maternal blood pressure but decreased fetal weights. Uterine artery blood flow was lower and resistance index was higher in the PFOS dams. In PFOS dams, uterine artery contractile responses to angiotensin II were significantly greater, whereas contractile responses to K+ depolarization and phenylephrine were unaffected. Plasma angiotensin II levels were not significantly different between control and PFOS dams; however, PFOS exposure significantly increased AGTR1 and decreased AGTR2 protein levels in uterine arteries. Endothelium-dependent relaxation response to acetylcholine was significantly reduced with decreased endothelial nitric oxide synthase expression in the uterine arteries of PFOS dams. Left ventricular hypertrophy and fibrosis were observed, along with increased ejection fraction and fractional shortening in PFOS dams. These results suggest that elevated maternal PFOS levels decrease uterine blood flow and increase vascular resistance via heightened angiotensin II-mediated vasoconstriction and impaired endothelium-dependent vasodilation, which provides a molecular mechanism linking elevated maternal PFOS levels with gestational hypertension and fetal growth restriction.
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Affiliation(s)
- Sri Vidya Dangudubiyyam
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA.,Endocrinology-Reproductive Physiology Program, University of Wisconsin, Madison, WI 53715, USA
| | - Jay S Mishra
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA
| | - Ruolin Song
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA
| | - Sathish Kumar
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53706, USA.,Department of Obstetrics and Gynecology, School of Medicine and Public Health, University of Wisconsin, Madison, WI 53792, USA.,Endocrinology-Reproductive Physiology Program, University of Wisconsin, Madison, WI 53715, USA
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15
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Tong W, Allison BJ, Brain KL, Patey OV, Niu Y, Botting KJ, Ford SG, Garrud TA, Wooding PF, Shaw CJ, Lyu Q, Zhang L, Ma J, Cindrova-Davies T, Yung HW, Burton GJ, Giussani DA. Chronic Hypoxia in Ovine Pregnancy Recapitulates Physiological and Molecular Markers of Preeclampsia in the Mother, Placenta, and Offspring. Hypertension 2022; 79:1525-1535. [PMID: 35534925 PMCID: PMC9172902 DOI: 10.1161/hypertensionaha.122.19175] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 04/20/2022] [Indexed: 02/02/2023]
Abstract
BACKGROUND Preeclampsia continues to be a prevalent pregnancy complication and underlying mechanisms remain controversial. A common feature of preeclampsia is utero-placenta hypoxia. In contrast to the impact of hypoxia on the placenta and fetus, comparatively little is known about the maternal physiology. METHODS We adopted an integrative approach to investigate the inter-relationship between chronic hypoxia during pregnancy with maternal, placental, and fetal outcomes, common in preeclampsia. We exploited a novel technique using isobaric hypoxic chambers and in vivo continuous cardiovascular recording technology for measurement of blood pressure in sheep and studied the placental stress in response to hypoxia at cellular and subcellular levels. RESULTS Chronic hypoxia in ovine pregnancy promoted fetal growth restriction (FGR) with evidence of fetal brain-sparing, increased placental hypoxia-mediated oxidative damage, and activated placental stress response pathways. These changes were linked with dilation of the placental endoplasmic reticulum (ER) cisternae and increased placental expression of the antiangiogenic factors sFlt-1 (soluble fms-like tyrosine kinase 1) and sEng (soluble endoglin), combined with a shift towards an angiogenic imbalance in the maternal circulation. Chronic hypoxia further led to an increase in uteroplacental vascular resistance and the fall in maternal blood pressure with advancing gestation measured in normoxic pregnancy did not occur in hypoxic pregnancy. CONCLUSIONS Therefore, we show in an ovine model of sea-level adverse pregnancy that chronic hypoxia recapitulates physiological and molecular features of preeclampsia in the mother, placenta, and offspring.
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Affiliation(s)
- Wen Tong
- Department of Physiology Development & Neuroscience, University of Cambridge, United Kingdom (W.T., B.J.A., K.L.B., O.V.P., Y.N., K.J.B., S.G.F., T.A.G., P.F.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
- Centre for Trophoblast Research, University of Cambridge, United Kingdom (W.T., Y.N., K.J.B., T.A.G., P.G.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
| | - Beth J. Allison
- Department of Physiology Development & Neuroscience, University of Cambridge, United Kingdom (W.T., B.J.A., K.L.B., O.V.P., Y.N., K.J.B., S.G.F., T.A.G., P.F.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
| | - Kirsty L. Brain
- Department of Physiology Development & Neuroscience, University of Cambridge, United Kingdom (W.T., B.J.A., K.L.B., O.V.P., Y.N., K.J.B., S.G.F., T.A.G., P.F.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
| | - Olga V. Patey
- Department of Physiology Development & Neuroscience, University of Cambridge, United Kingdom (W.T., B.J.A., K.L.B., O.V.P., Y.N., K.J.B., S.G.F., T.A.G., P.F.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
| | - Youguo Niu
- Department of Physiology Development & Neuroscience, University of Cambridge, United Kingdom (W.T., B.J.A., K.L.B., O.V.P., Y.N., K.J.B., S.G.F., T.A.G., P.F.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
- Centre for Trophoblast Research, University of Cambridge, United Kingdom (W.T., Y.N., K.J.B., T.A.G., P.G.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
- BHF Cardiovascular Centre for Research Excellence, University of Cambridge, United Kingdom (Y.N., K.J.B., D.A.S.)
- Department of Aerospace Physiology, Fourth Military Medical University, Xi’an, China (Y.N., Q.L., L.Z., J.M., D.A.G.)
| | - Kimberley J. Botting
- Department of Physiology Development & Neuroscience, University of Cambridge, United Kingdom (W.T., B.J.A., K.L.B., O.V.P., Y.N., K.J.B., S.G.F., T.A.G., P.F.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
- Centre for Trophoblast Research, University of Cambridge, United Kingdom (W.T., Y.N., K.J.B., T.A.G., P.G.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
- BHF Cardiovascular Centre for Research Excellence, University of Cambridge, United Kingdom (Y.N., K.J.B., D.A.S.)
| | - Sage G. Ford
- Department of Physiology Development & Neuroscience, University of Cambridge, United Kingdom (W.T., B.J.A., K.L.B., O.V.P., Y.N., K.J.B., S.G.F., T.A.G., P.F.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
| | - Tessa A. Garrud
- Department of Physiology Development & Neuroscience, University of Cambridge, United Kingdom (W.T., B.J.A., K.L.B., O.V.P., Y.N., K.J.B., S.G.F., T.A.G., P.F.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
- Centre for Trophoblast Research, University of Cambridge, United Kingdom (W.T., Y.N., K.J.B., T.A.G., P.G.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
| | - Peter F.B. Wooding
- Department of Physiology Development & Neuroscience, University of Cambridge, United Kingdom (W.T., B.J.A., K.L.B., O.V.P., Y.N., K.J.B., S.G.F., T.A.G., P.F.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
- Centre for Trophoblast Research, University of Cambridge, United Kingdom (W.T., Y.N., K.J.B., T.A.G., P.G.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
| | - Caroline J. Shaw
- Department of Metabolism, Digestion and Reproduction, Imperial College London, United Kingdom (C.J.S.)
| | - Qiang Lyu
- Department of Aerospace Physiology, Fourth Military Medical University, Xi’an, China (Y.N., Q.L., L.Z., J.M., D.A.G.)
| | - Lin Zhang
- Department of Aerospace Physiology, Fourth Military Medical University, Xi’an, China (Y.N., Q.L., L.Z., J.M., D.A.G.)
| | - Jin Ma
- Department of Aerospace Physiology, Fourth Military Medical University, Xi’an, China (Y.N., Q.L., L.Z., J.M., D.A.G.)
| | - Tereza Cindrova-Davies
- Department of Physiology Development & Neuroscience, University of Cambridge, United Kingdom (W.T., B.J.A., K.L.B., O.V.P., Y.N., K.J.B., S.G.F., T.A.G., P.F.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
- Centre for Trophoblast Research, University of Cambridge, United Kingdom (W.T., Y.N., K.J.B., T.A.G., P.G.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
| | - Hong Wa Yung
- Department of Physiology Development & Neuroscience, University of Cambridge, United Kingdom (W.T., B.J.A., K.L.B., O.V.P., Y.N., K.J.B., S.G.F., T.A.G., P.F.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
- Centre for Trophoblast Research, University of Cambridge, United Kingdom (W.T., Y.N., K.J.B., T.A.G., P.G.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
| | - Graham J. Burton
- Department of Physiology Development & Neuroscience, University of Cambridge, United Kingdom (W.T., B.J.A., K.L.B., O.V.P., Y.N., K.J.B., S.G.F., T.A.G., P.F.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
- Centre for Trophoblast Research, University of Cambridge, United Kingdom (W.T., Y.N., K.J.B., T.A.G., P.G.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
| | - Dino A. Giussani
- Department of Physiology Development & Neuroscience, University of Cambridge, United Kingdom (W.T., B.J.A., K.L.B., O.V.P., Y.N., K.J.B., S.G.F., T.A.G., P.F.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
- Centre for Trophoblast Research, University of Cambridge, United Kingdom (W.T., Y.N., K.J.B., T.A.G., P.G.B.W., T.C.-D., H.W.Y., G.J.B., D.A.G.)
- BHF Cardiovascular Centre for Research Excellence, University of Cambridge, United Kingdom (Y.N., K.J.B., D.A.S.)
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16
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Grant ID, Giussani DA, Aiken CE. Fetal growth and spontaneous preterm birth in high-altitude pregnancy: A systematic review, meta-analysis, and meta-regression. Int J Gynaecol Obstet 2022; 157:221-229. [PMID: 34101174 DOI: 10.1002/ijgo.13779] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 05/17/2021] [Accepted: 06/07/2021] [Indexed: 01/12/2023]
Abstract
OBJECTIVE To understand the relationship between birth weight and altitude to improve health outcomes in high-altitude populations, to systematically assess the impact of altitude on the likelihood of low birth weight (LBW), small for gestational age (SGA), and spontaneous preterm birth (sPTB), and to estimate the magnitude of reduced birth weight associated with altitude. METHODS PubMed, OvidEMBASE, Cochrane Library, Medline, Web of Science, and clinicaltrials.gov were searched (from inception to November 11, 2020). Observational, cohort, or case-control studies were included if they reported a high altitude (>2500 m) and appropriate control population. RESULTS Of 2524 studies identified, 59 were included (n = 1 604 770 pregnancies). Data were abstracted according to PRISMA guidelines, and were pooled using random-effects models. There are greater odds of LBW (odds ratio [OR] 1.47, 95% confidence interval [CI] 1.33-1.62, P < 0.001), SGA (OR 1.88, 95% CI 1.08-3.28, P = 0.026), and sPTB (OR 1.23, 95% CI 1.04-1.47, P = 0.016) in high- versus low-altitude pregnancies. Birth weight decreases by 54.7 g (±13.0 g, P < 0.0001) per 1000 m increase in altitude. Average gestational age at delivery was not significantly different. CONCLUSION Globally, the likelihood of adverse perinatal outcomes, including LBW, SGA, and sPTB, increases in high-altitude pregnancies. There is an inverse relationship between birth weight and altitude. These findings have important implications for the increasing global population living at altitudes above 2500 m.
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Affiliation(s)
- Imogen D Grant
- University Department of Obstetrics and Gynaecology, University of Cambridge, NIHR Cambridge Biomedical Research Centre, Cambridge, UK
| | - Dino A Giussani
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
| | - Catherine E Aiken
- University Department of Obstetrics and Gynaecology, University of Cambridge, NIHR Cambridge Biomedical Research Centre, Cambridge, UK
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17
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Jones AK, Rozance PJ, Brown LD, Lorca RA, Julian CG, Moore LG, Limesand SW, Wesolowski SR. Uteroplacental nutrient flux and evidence for metabolic reprogramming during sustained hypoxemia. Physiol Rep 2021; 9:e15033. [PMID: 34558219 PMCID: PMC8461030 DOI: 10.14814/phy2.15033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 08/23/2021] [Indexed: 01/14/2023] Open
Abstract
Gestational hypoxemia is often associated with reduced birth weight, yet how hypoxemia controls uteroplacental nutrient metabolism and supply to the fetus is unclear. This study tested the effects of maternal hypoxemia (HOX) between 0.8 and 0.9 gestation on uteroplacental nutrient metabolism and flux to the fetus in pregnant sheep. Despite hypoxemia, uteroplacental and fetal oxygen utilization and net glucose and lactate uptake rates were similar in HOX (n = 11) compared to CON (n = 7) groups. HOX fetuses had increased lactate and pyruvate concentrations and increased net pyruvate output to the utero-placenta. In the HOX group, uteroplacental flux of alanine to the fetus was decreased, as was glutamate flux from the fetus. HOX fetuses had increased alanine and decreased aspartate, serine, and glutamate concentrations. In HOX placental tissue, we identified hypoxic responses that should increase mitochondrial efficiency (decreased SDHB, increased COX4I2) and increase lactate production from pyruvate (increased LDHA protein and LDH activity, decreased LDHB and MPC2), both resembling metabolic reprogramming, but with evidence for decreased (PFK1, PKM2), rather than increased, glycolysis and AMPK phosphorylation. This supports a fetal-uteroplacental shuttle during sustained hypoxemia whereby uteroplacental tissues produce lactate as fuel for the fetus using pyruvate released from the fetus, rather than pyruvate produced from glucose in the placenta, given the absence of increased uteroplacental glucose uptake and glycolytic gene activation. Together, these results provide new mechanisms for how hypoxemia, independent of AMPK activation, regulates uteroplacental metabolism and nutrient allocation to the fetus, which allow the fetus to defend its oxidative metabolism and growth.
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Affiliation(s)
- Amanda K. Jones
- Perinatal Research Center, Department of PediatricsUniversity of Colorado School of MedicineAuroraColoradoUSA
| | - Paul J. Rozance
- Perinatal Research Center, Department of PediatricsUniversity of Colorado School of MedicineAuroraColoradoUSA
| | - Laura D. Brown
- Perinatal Research Center, Department of PediatricsUniversity of Colorado School of MedicineAuroraColoradoUSA
| | - Ramón A. Lorca
- Department of Obstetrics and GynecologyUniversity of Colorado School of MedicineAuroraColoradoUSA
| | - Colleen G. Julian
- Department of MedicineUniversity of Colorado School of MedicineAuroraColoradoUSA
| | - Lorna G. Moore
- Department of Obstetrics and GynecologyUniversity of Colorado School of MedicineAuroraColoradoUSA
| | - Sean W. Limesand
- School of Animal and Comparative Biomedical SciencesUniversity of ArizonaTucsonArizonaUSA
| | - Stephanie R. Wesolowski
- Perinatal Research Center, Department of PediatricsUniversity of Colorado School of MedicineAuroraColoradoUSA
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18
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Grant ID, Giussani DA, Aiken CE. Blood pressure and hypertensive disorders of pregnancy at high altitude: a systematic review and meta-analysis. Am J Obstet Gynecol MFM 2021; 3:100400. [PMID: 34023533 DOI: 10.1016/j.ajogmf.2021.100400] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 05/06/2021] [Accepted: 05/15/2021] [Indexed: 01/17/2023]
Abstract
OBJECTIVE Exposure to high altitude (≥2500 m) is associated with increased arterial blood pressure. During pregnancy, even a mild elevation of maternal blood pressure is associated with reduced birthweight and increased prevalence of pregnancy complications. This study aimed to systematically assess the impact of altitude on maternal blood pressure at term and on the prevalence of hypertensive disorders of pregnancy. DATA SOURCES PubMed, Ovid Embase, Cochrane Library, Medline, Web of Science, and ClinicalTrials.gov were searched (inception to November 11, 2020). STUDY APPRAISAL AND SYNTHESIS METHODS Observational, cohort, or case-control studies were included if they reported a high-altitude and appropriate control pregnant population. Studies published >50 years ago were excluded; 2 reviewers independently assessed articles for eligibility and risk of bias. RESULTS At high altitude, maternal systolic and diastolic blood pressure at term was higher than at low altitude (4.8±1.6 mm Hg; P<.001; 4.0±0.8 mm Hg; P<.001, respectively). Hypertensive disorders of pregnancy were more common at high altitude (odds ratio, 1.31 [1.03-1.65]; P<.05). The prevalence of gestational hypertension was nearly twice as high at high altitude (odds ratio, 1.92 [1.15-3.22]; P<.05) but the prevalence of preeclampsia was half as high (odds ratio, 0.57 [0.46-0.70]; P<.001). The likelihood of stillbirth was increased by 63% in pregnancies at high altitude compared with low altitude (odds ratio, 1.63 [1.12-2.35]; P<.01). CONCLUSION Maternal blood pressure is higher at term in pregnancies at high altitude than low altitude, accompanied with an increased risk of gestational hypertension but not preeclampsia. Risk of stillbirth at high altitude is also increased. With a growing population residing at high altitude worldwide, it is essential to clearly define the associated risk of adverse pregnancy outcomes.
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Affiliation(s)
- Imogen D Grant
- Department of Obstetrics and Gynaecology (Ms Grant and Dr Aiken); NIHR Cambridge Biomedical Research Centre, Cambridge, United Kingdom (Ms Grant and Dr Aiken).
| | - Dino A Giussani
- Department of Physiology, Development and Neuroscience (Dr Giussani), University of Cambridge, Cambridge, United Kingdom
| | - Catherine E Aiken
- Department of Obstetrics and Gynaecology (Ms Grant and Dr Aiken); NIHR Cambridge Biomedical Research Centre, Cambridge, United Kingdom (Ms Grant and Dr Aiken)
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19
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Wilsterman K, Cheviron ZA. Fetal growth, high altitude, and evolutionary adaptation: a new perspective. Am J Physiol Regul Integr Comp Physiol 2021; 321:R279-R294. [PMID: 34259046 DOI: 10.1152/ajpregu.00067.2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Residence at high altitude is consistently associated with low birthweight among placental mammals. This reduction in birthweight influences long-term health trajectories for both the offspring and mother. However, the physiological processes that contribute to fetal growth restriction at altitude are still poorly understood, and thus our ability to safely intervene remains limited. One approach to identify the factors that mitigate altitude-dependent fetal growth restriction is to study populations that are protected from fetal growth restriction through evolutionary adaptations (e.g., high altitude-adapted populations). Here, we examine human gestational physiology at high altitude from a novel evolutionary perspective that focuses on patterns of physiological plasticity, allowing us to identify 1) the contribution of specific physiological systems to fetal growth restriction and 2) the mechanisms that confer protection in highland-adapted populations. Using this perspective, our review highlights two general findings: first, that the beneficial value of plasticity in maternal physiology is often dependent on factors more proximate to the fetus; and second, that our ability to understand the contributions of these proximate factors is currently limited by thin data from altitude-adapted populations. Expanding the comparative scope of studies on gestational physiology at high altitude and integrating studies of both maternal and fetal physiology are needed to clarify the mechanisms by which physiological responses to altitude contribute to fetal growth outcomes. The relevance of these questions to clinical, agricultural, and basic research combined with the breadth of the unknown highlight gestational physiology at high altitude as an exciting niche for continued work.
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Affiliation(s)
- Kathryn Wilsterman
- Division of Biological Sciences, University of Montana, Missoula, Montana
| | - Zachary A Cheviron
- Division of Biological Sciences, University of Montana, Missoula, Montana
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20
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Storz JF. High-Altitude Adaptation: Mechanistic Insights from Integrated Genomics and Physiology. Mol Biol Evol 2021; 38:2677-2691. [PMID: 33751123 PMCID: PMC8233491 DOI: 10.1093/molbev/msab064] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Population genomic analyses of high-altitude humans and other vertebrates have identified numerous candidate genes for hypoxia adaptation, and the physiological pathways implicated by such analyses suggest testable hypotheses about underlying mechanisms. Studies of highland natives that integrate genomic data with experimental measures of physiological performance capacities and subordinate traits are revealing associations between genotypes (e.g., hypoxia-inducible factor gene variants) and hypoxia-responsive phenotypes. The subsequent search for causal mechanisms is complicated by the fact that observed genotypic associations with hypoxia-induced phenotypes may reflect second-order consequences of selection-mediated changes in other (unmeasured) traits that are coupled with the focal trait via feedback regulation. Manipulative experiments to decipher circuits of feedback control and patterns of phenotypic integration can help identify causal relationships that underlie observed genotype–phenotype associations. Such experiments are critical for correct inferences about phenotypic targets of selection and mechanisms of adaptation.
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Affiliation(s)
- Jay F Storz
- School of Biological Sciences, University of Nebraska, Lincoln, NE, USA
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21
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Lorca RA, Houck JA, Laurent LC, Matarazzo CJ, Baker K, Horii M, Nelson KK, Bales ES, Euser AG, Parast MM, Moore LG, Julian CG. High altitude regulates the expression of AMPK pathways in human placenta. Placenta 2021; 104:267-276. [PMID: 33472134 DOI: 10.1016/j.placenta.2021.01.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 12/29/2020] [Accepted: 01/08/2021] [Indexed: 12/24/2022]
Abstract
INTRODUCTION High-altitude (>2500 m) residence augments the risk of intrauterine growth restriction (IUGR) and preeclampsia likely due, in part, to uteroplacental hypoperfusion. Previous genomic and transcriptomic studies in humans and functional studies in mice and humans suggest a role for AMP-activated protein kinase (AMPK) pathway in protecting against hypoxia-associated IUGR. AMPK is a metabolic sensor activated by hypoxia that is ubiquitously expressed in vascular beds and placenta. METHODS We measured gene expression and protein levels of AMPK and its upstream regulators and downstream targets in human placentas from high (>2500 m) vs. moderate (~1700 m) and low (~100 m) altitude. RESULTS We found that phosphorylated AMPK protein levels and its downstream target TSC2 were increased in placentas from high and moderate vs. low altitude, whereas the phosphorylated form of the downstream target translation repressor protein 4E-BP1 was increased in high compared to moderate as well as low altitude placentas. Mean birth weights progressively fell with increasing altitude but no infants, by study design, were clinically growth-restricted. Gene expression analysis showed moderate increases in PRKAG2, encoding the AMPK γ2 subunit, and mechanistic target of rapamycin, MTOR, expression. DISCUSSION These results highlight a differential regulation of placental AMPK pathway activation in women residing at low, moderate or high altitude during pregnancy, suggesting AMPK may be serving as a metabolic regulator for integrating hypoxic stimuli with placental function.
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Affiliation(s)
- Ramón A Lorca
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO, 80045, USA.
| | - Julie A Houck
- Division of Biomedical Informatics and Personalized Medicine, Department of Medicine, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Louise C Laurent
- Department of Reproductive Medicine, University of California San Diego, La Jolla, 92093, USA
| | - Christopher J Matarazzo
- Division of Biomedical Informatics and Personalized Medicine, Department of Medicine, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Kori Baker
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Mariko Horii
- Department of Pathology, University of California San Diego, La Jolla, 92093, USA
| | - Katharine K Nelson
- Department of Pathology, University of California San Diego, La Jolla, 92093, USA
| | - Elise S Bales
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Anna G Euser
- Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Mana M Parast
- Department of Pathology, University of California San Diego, La Jolla, 92093, USA
| | - Lorna G Moore
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Colleen G Julian
- Division of Biomedical Informatics and Personalized Medicine, Department of Medicine, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO, 80045, USA
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22
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Robertson CE, Wilsterman K. Developmental and reproductive physiology of small mammals at high altitude: challenges and evolutionary innovations. ACTA ACUST UNITED AC 2020; 223:223/24/jeb215350. [PMID: 33443053 DOI: 10.1242/jeb.215350] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
High-altitude environments, characterized by low oxygen levels and low ambient temperatures, have been repeatedly colonized by small altricial mammals. These species inhabit mountainous regions year-round, enduring chronic cold and hypoxia. The adaptations that allow small mammals to thrive at altitude have been well studied in non-reproducing adults; however, our knowledge of adaptations specific to earlier life stages and reproductive females is extremely limited. In lowland natives, chronic hypoxia during gestation affects maternal physiology and placental function, ultimately limiting fetal growth. During post-natal development, hypoxia and cold further limit growth both directly by acting on neonatal physiology and indirectly via impacts on maternal milk production and care. Although lowland natives can survive brief sojourns to even extreme high altitude as adults, reproductive success in these environments is very low, and lowland young rarely survive to sexual maturity in chronic cold and hypoxia. Here, we review the limits to maternal and offspring physiology - both pre-natal and post-natal - that highland-adapted species have overcome, with a focus on recent studies on high-altitude populations of the North American deer mouse (Peromyscus maniculatus). We conclude that a combination of maternal and developmental adaptations were likely to have been critical steps in the evolutionary history of high-altitude native mammals.
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Affiliation(s)
| | - Kathryn Wilsterman
- Division of Biological Sciences, University of Montana, Missoula, MT 59802, USA
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23
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Maternal altitude and risk of low birthweight: A systematic review and meta-analyses. Placenta 2020; 101:124-131. [DOI: 10.1016/j.placenta.2020.09.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 09/07/2020] [Accepted: 09/10/2020] [Indexed: 11/18/2022]
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Grant I, Soria R, Julian CG, Vargas E, Moore LG, Aiken CE, Giussani DA. Parental ancestry and risk of early pregnancy loss at high altitude. FASEB J 2020; 34:13741-13749. [PMID: 32856356 DOI: 10.1096/fj.202001257r] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 07/20/2020] [Accepted: 07/31/2020] [Indexed: 11/11/2022]
Abstract
High altitude pregnancy is associated with increased frequency of low birth weight infants and neonatal complications, the risks of which are higher in women of low-altitude ancestry. Does ancestry also influence the risk of miscarriage (pregnancy loss <20 weeks) in high-altitude pregnancy? To answer this, 5386 women from La Paz, Bolivia (3300-4150 m) with ≥1 live-born infant were identified. Data were extracted from medical records including maternal and paternal ancestry, demographic factors, and reproductive history. The risk of miscarriage by ancestry was assessed using multivariate logistic regression, adjusting for parity, and maternal age. Andean women experienced first live-births younger than Mestizo or European women (21.7 ± 4.6 vs 23.4 ± 8.0 vs 24.1 ± 5.1, P < .001). Andeans experienced more pregnancies per year of reproductive life (P < .001) and had significantly higher ratios of live-births to miscarriages than women of Mestizo or European ancestry (P < .001). Andean women were 24% less likely to have ever experienced a miscarriage compared to European women (OR:0.76; CI:0.62-0.90, P < .001). The woman's partner's ancestry wasn't a significant independent predictor of miscarriage. In conclusion, the risk of miscarriage at high altitude is lower in Andean women. The lack of a paternal ancestry effect suggests underlying mechanisms relate more to differential maternal adaptation in early pregnancy than fetal genetics.
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Affiliation(s)
- I Grant
- Department of Obstetrics and Gynaecology, NIHR Cambridge Biomedical Research Centre, University of Cambridge, Cambridge, UK
| | - R Soria
- Instituto Boliviano de Biología de Altura, La Paz, Bolivia
| | - C G Julian
- Department of Medicine, University of Colorado, Denver, CO, USA
| | - E Vargas
- Instituto Boliviano de Biología de Altura, La Paz, Bolivia
| | - L G Moore
- Department of Obstetrics/Gynecology, University of Colorado, Denver, CO, USA
| | - C E Aiken
- Department of Obstetrics and Gynaecology, NIHR Cambridge Biomedical Research Centre, University of Cambridge, Cambridge, UK
| | - D A Giussani
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
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25
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Maternal exposure to low-to-medium altitude and birth outcomes: evidence from a population-based study in Chinese newborns. J Dev Orig Health Dis 2020; 12:443-451. [PMID: 32662389 DOI: 10.1017/s204017442000063x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Despite high altitude was implicated in adverse birth outcomes, there remained a paucity of evidence on low-to-medium altitude effect. This study aimed to explore the association of low-to-medium altitude with birth outcomes. A population-based cross-sectional survey was performed using a stratified multistage random sampling method among women with their infants born during 2010-2013 in Northwestern China. Altitude was determined in meters based on the village or community of the mother's living areas. Birth outcomes involved birth weight, gestational age, and small for gestational age (SGA). Generalized linear models were fitted to investigate the association of altitude with birth outcomes. Moreover, the dose-response relationship between altitude and birth outcomes was evaluated with a restricted cubic spline function. A total of 27 801 women with their infants were included. After adjusting for potential confounders, every 100-m increase in the altitude was associated with reduced birth weight by 6.4 (95% CI -8.1, -4.6) g, the slight increase of gestational age by 0.015 (95% CI 0.010, 0.020) week, and an increased risk of SGA birth (odds ratio 1.03, 95% CI 1.02, 1.04). Moreover, there was an inversely linear relationship between altitude and birth weight (P for overall < 0.001 and P for nonlinear = 0.312), and a positive linear relationship between altitude and SGA (P for overall < 0.001 and P for nonlinear = 0.194). However, a nonlinear relationship was observed between altitude and gestational age (P for overall < 0.001 and P for nonlinear = 0.010). The present results suggest that low-to-medium altitude is possibly associated with adverse birth outcomes.
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Lorca RA, Matarazzo CJ, Bales ES, Houck JA, Orlicky DJ, Euser AG, Julian CG, Moore LG. AMPK activation in pregnant human myometrial arteries from high-altitude and intrauterine growth-restricted pregnancies. Am J Physiol Heart Circ Physiol 2020; 319:H203-H212. [PMID: 32502374 DOI: 10.1152/ajpheart.00644.2019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
High-altitude (>2,500 m) residence increases the incidence of intrauterine growth restriction (IUGR) due, in part, to reduced uterine artery blood flow and impaired myometrial artery (MA) vasodilator response. A role for the AMP-activated protein kinase (AMPK) pathway in protecting against hypoxia-associated IUGR is suggested by genomic and transcriptomic studies in humans and functional studies in mice. AMPK is a hypoxia-sensitive metabolic sensor with vasodilatory properties. Here we hypothesized that AMPK-dependent vasodilation was increased in MAs from high versus low-altitude (<1,700 m) Colorado women with appropriate for gestational age (AGA) pregnancies and reduced in IUGR pregnancies regardless of altitude. Vasoreactivity studies showed that, in AGA pregnancies, MAs from high-altitude women were more sensitive to vasodilation by activation of AMPK with A769662 due chiefly to increased endothelial nitric oxide production, whereas MA responses to AMPK activation in the low-altitude women were endothelium independent. MAs from IUGR compared with AGA pregnancies had blunted vasodilator responses to acetylcholine at high altitude. We concluded that 1) blunted vasodilator responses in IUGR pregnancies confirm the importance of MA vasodilation for normal fetal growth and 2) the increased sensitivity to AMPK activation in AGA pregnancies at high altitude suggests that AMPK activation helped maintain MA vasodilation and fetal growth. These results highlight a novel mechanism for vasodilation of MAs under conditions of chronic hypoxia and suggest that AMPK activation could provide a therapy for increasing uteroplacental blood flow and improving fetal growth in IUGR pregnancies.NEW & NOTEWORTHY Intrauterine growth restriction (IUGR) impairs infant well- being and increases susceptibility to later-in-life diseases for mother and child. Our study reveals a novel role for AMPK in vasodilating the myometrial artery (MA) from women residing at high altitude (>2,500 m) with appropriate for gestational age pregnancies but not in IUGR pregnancies at any altitude.
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Affiliation(s)
- Ramón A Lorca
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, Colorado
| | - Christopher J Matarazzo
- Division of Biomedical Informatics and Personalized Medicine, Department of Medicine, University of Colorado Denver-Anschutz Medical Campus, Aurora, Colorado
| | - Elise S Bales
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, Colorado
| | - Julie A Houck
- Division of Biomedical Informatics and Personalized Medicine, Department of Medicine, University of Colorado Denver-Anschutz Medical Campus, Aurora, Colorado
| | - David J Orlicky
- Department of Pathology, University of Colorado Denver-Anschutz Medical Campus, Aurora, Colorado
| | - Anna G Euser
- Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, Colorado
| | - Colleen G Julian
- Division of Biomedical Informatics and Personalized Medicine, Department of Medicine, University of Colorado Denver-Anschutz Medical Campus, Aurora, Colorado
| | - Lorna G Moore
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, Colorado
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Lane SL, Doyle AS, Bales ES, Lorca RA, Julian CG, Moore LG. Increased uterine artery blood flow in hypoxic murine pregnancy is not sufficient to prevent fetal growth restriction†. Biol Reprod 2020; 102:660-670. [PMID: 31711123 PMCID: PMC7068112 DOI: 10.1093/biolre/ioz208] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 08/19/2019] [Accepted: 10/28/2019] [Indexed: 12/14/2022] Open
Abstract
Incomplete maternal vascular responses to pregnancy contribute to pregnancy complications including intrauterine growth restriction (IUGR) and preeclampsia. We aimed to characterize maternal vascular dysfunction in a murine model of fetal growth restriction as an approach toward identifying targetable pathways for improving pregnancy outcomes. We utilized a murine model of late-gestation hypoxia-induced IUGR that reduced E18.5 fetal weight by 34%. Contrary to our hypothesis, uterine artery blood flow as measured in vivo by Doppler ultrasound was increased in mice housed under hypobaric hypoxia (385 mmHg; 5500 m) vs normoxia (760 mmHg; 0 m). Using wire myography, uterine arteries isolated from hypoxic mice had similar vasodilator responses to the two activators A769662 and acetylcholine as those from normoxic mice, although the contribution of an increase in nitric oxide production to uterine artery vasodilation was reduced in the hypoxic vs normoxic groups. Vasoconstrictor responses to phenylephrine and potassium chloride were unaltered by hypoxia. The levels of activated adenosine monophosphate-activated protein kinase (AMPK) were reduced with hypoxia in both the uterine artery and placenta as measured by western blot and immunohistochemistry. We concluded that the rise in uterine artery blood flow may be compensatory to hypoxia but was not sufficient to prevent fetal growth restriction. Although AMPK signaling was reduced by hypoxia, AMPK was still receptive to pharmacologic activation in the uterine arteries in which it was a potent vasodilator. Thus, AMPK activation may represent a new therapy for pregnancy complications involving reduced uteroplacental perfusion.
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Affiliation(s)
- Sydney L Lane
- Integrated Physiology PhD Program, University of Colorado Denver Graduate School, Aurora, CO, USA
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado-Denver Anschutz Medical Campus, Aurora, CO, USA
| | - Alexandrea S Doyle
- Division of Bioinformatics and Personalized Medicine, Department of Medicine, University of Colorado-Denver Anschutz Medical Campus, Aurora, CO, USA
| | - Elise S Bales
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado-Denver Anschutz Medical Campus, Aurora, CO, USA
| | - Ramón A Lorca
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado-Denver Anschutz Medical Campus, Aurora, CO, USA
| | - Colleen G Julian
- Division of Bioinformatics and Personalized Medicine, Department of Medicine, University of Colorado-Denver Anschutz Medical Campus, Aurora, CO, USA
| | - Lorna G Moore
- Division of Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado-Denver Anschutz Medical Campus, Aurora, CO, USA
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Lane SL, Doyle AS, Bales ES, Houck JA, Lorca RA, Moore LG, Julian CG. Peroxisome proliferator-activated receptor gamma blunts endothelin-1-mediated contraction of the uterine artery in a murine model of high-altitude pregnancy. FASEB J 2020; 34:4283-4292. [PMID: 31970838 DOI: 10.1096/fj.201902264rr] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 01/02/2020] [Accepted: 01/08/2020] [Indexed: 01/12/2023]
Abstract
The environmental hypoxia of high altitude (HA) increases the incidence of intrauterine growth restriction (IUGR) approximately threefold. The peroxisome proliferator-activated receptor γ (PPAR-γ), a ligand-activated nuclear receptor that promotes vasorelaxation by increasing nitric oxide and downregulating endothelin-1 (ET-1) production, has been implicated in IUGR. Based on our prior work indicating that pharmacologic activation of the PPARγ pathway protects against hypoxia-associated IUGR, we used an experimental murine model to determine whether such effects may be attributed to vasodilatory effects in the uteroplacental circulation. Using wire myography, ex vivo vasoreactivity studies were conducted in uterine arteries (UtA) isolated from pregnant mice exposed to hypoxia or normoxia from gestational day 14.5 to 18.5. Exposure to troglitazone, a high-affinity PPARγ agonist-induced vasorelaxation in UtA preconstricted with phenylephrine, with HA-UtA showing increased sensitivity. Troglitazone blunted ET-1-induced contraction of UtA in hypoxic and normoxic dams equivalently. Immunohistological analysis revealed enhanced staining for ET-1 receptors in the placental labyrinthine zone in hypoxic compared to normoxic dams. Our results suggest that pharmacologic PPAR-γ activation, via its vasoactive properties, may protect the fetal growth under hypoxic conditions by improving uteroplacental perfusion and thereby justify further investigation into PPARγ as a therapeutic target for IUGR in pregnancies complicated by hypoxia.
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Affiliation(s)
- Sydney L Lane
- Integrated Physiology Program, University of Colorado Graduate School, Aurora, CO, USA.,Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Alexandrea S Doyle
- Department of Biochemistry, Colorado Mesa University, Grand Junction, CO, USA
| | - Elise S Bales
- Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Julie A Houck
- Department of Biochemistry, Colorado Mesa University, Grand Junction, CO, USA
| | - Ramón A Lorca
- Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Lorna G Moore
- Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Colleen G Julian
- Department of Medicine, University of Colorado School of Medicine, Aurora, CO, USA
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Vaughan OR, Thompson F, Lorca RA, Julian CG, Powell TL, Moore LG, Jansson T. Effect of high altitude on human placental amino acid transport. J Appl Physiol (1985) 2019; 128:127-133. [PMID: 31804891 DOI: 10.1152/japplphysiol.00691.2019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Women residing at high altitudes deliver infants of lower birth weight than at sea level. Birth weight correlates with placental system A-mediated amino acid transport capacity, and severe environmental hypoxia reduces system A activity in isolated trophoblast and the mouse placenta. However, the effect of high altitude on human placental amino acid transport remains unknown. We hypothesized that microvillous membrane (MVM) system A and system L amino acid transporter activity is lower in placentas of women living at high altitude compared with low-altitude controls. Placentas were collected at term from healthy pregnant women residing at high altitude (HA; >2,500 m; n = 14) or low altitude (LA; <1,700 m; n = 14) following planned, unlabored cesarean section. Birth weight, but not placenta weight, was 13% lower in HA pregnancies (2.88 ± 0.11 kg) compared with LA (3.30 ± 0.07 kg, P < 0.01). MVM erythropoietin receptor abundance, determined by immunoblot, was greater in HA than in LA placentas, consistent with lower placental oxygen levels at HA. However, there was no effect of altitude on MVM system A or L activity, determined by Na+-dependent [14C]methylaminoisobutyric acid uptake and [3H]leucine uptake, respectively. MVM abundance of glucose transporters (GLUTs) 1 and 4 and basal membrane GLUT4 were also similar in LA and HA placentas. Low birth weights in the neonates of women residing at high altitude are not a consequence of reduced placental amino acid transport capacity. These observations are in general agreement with studies of IUGR babies at low altitude, in which MVM system A activity is downregulated only in growth-restricted babies with significant compromise.NEW & NOTEWORTHY Babies born at high altitude are smaller than at sea level. Birth weight is dependent on growth in utero and, in turn, placental nutrient transport. We determined amino acid transport capacity in placentas collected from women resident at low and high altitude. Altitude did not affect system A amino acid transport across the syncytiotrophoblast microvillous membrane, suggesting that impaired placental amino acid transport does not contribute to reduced birth weight in this high-altitude population.
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Affiliation(s)
- Owen R Vaughan
- Department of Ob/Gyn, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Fredrick Thompson
- Department of Ob/Gyn, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Ramón A Lorca
- Department of Ob/Gyn, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Colleen G Julian
- Department of Medicine University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Theresa L Powell
- Department of Ob/Gyn, University of Colorado Anschutz Medical Campus, Aurora, Colorado.,Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Lorna G Moore
- Department of Ob/Gyn, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Thomas Jansson
- Department of Ob/Gyn, University of Colorado Anschutz Medical Campus, Aurora, Colorado
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Lorca RA, Lane SL, Bales ES, Nsier H, Yi H, Donnelly MA, Euser AG, Julian CG, Moore LG. High Altitude Reduces NO-Dependent Myometrial Artery Vasodilator Response During Pregnancy. Hypertension 2019; 73:1319-1326. [PMID: 31006328 DOI: 10.1161/hypertensionaha.119.12641] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The chronic hypoxia of high-altitude (HA) residence reduces uterine artery blood flow during pregnancy, likely contributing to an increased frequency of preeclampsia and intrauterine growth restriction. We hypothesized that this lesser pregnancy blood flow rise was due, in part, to reduced vasodilation of myometrial arteries (MAs). Here, we assessed MA vasoreactivity in healthy residents of high (2902±39 m) or low altitude (LA; 1669±10 m). MA contractile responses to potassium chloride, phenylephrine, or the thromboxane A2 agonist U46619 did not differ between LA and HA women. Acetylcholine vasodilated phenylephrine or U466119 preconstricted MAs at LA, yet had no effect on HA MAs. In contrast, another vasodilator, bradykinin, relaxed MAs from both altitudes similarly. At LA, the NO synthase inhibitor L-NG-nitroarginine methyl ester decreased both acetylcholine and bradykinin vasodilation by 56% and 33%, respectively. L-NG-nitroarginine methyl ester plus the COX (cyclooxygenase) inhibitor indomethacin had similar effects on acetylcholine and bradykinin vasodilation (68% and 42% reduction, respectively) as did removing the endothelium (78% and 50% decrease, respectively), suggesting a predominantly NO-dependent vasodilation at LA. However, at HA, L-NG-nitroarginine methyl ester did not change bradykinin vasodilation, whereas indomethacin or endothelium removal decreased it by 28% and 72%, respectively, indicating impaired NO signaling at HA. Suggesting that the impairment was downstream of eNOS (endothelial NO synthase), HA attenuated the vasodilation elicited by the NO donor sodium nitroprusside. We concluded that reduced NO-dependent MA vasodilation likely contributes to diminished uteroplacental perfusion in HA pregnancies.
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Affiliation(s)
- Ramón A Lorca
- From the Division of Reproductive Sciences (R.A.L., S.L.L., E.S.B., L.G.M.), University of Colorado Denver, Aurora
| | - Sydney L Lane
- From the Division of Reproductive Sciences (R.A.L., S.L.L., E.S.B., L.G.M.), University of Colorado Denver, Aurora
| | - Elise S Bales
- From the Division of Reproductive Sciences (R.A.L., S.L.L., E.S.B., L.G.M.), University of Colorado Denver, Aurora
| | - Hisham Nsier
- BA/BS-MD Program, College of Liberal Arts and Sciences (H.N., H.Y.), University of Colorado Denver, Aurora
| | - HeaMi Yi
- BA/BS-MD Program, College of Liberal Arts and Sciences (H.N., H.Y.), University of Colorado Denver, Aurora
| | - Meghan A Donnelly
- Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology (M.A.D., A.G.E.), University of Colorado Denver, Aurora
| | - Anna G Euser
- Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology (M.A.D., A.G.E.), University of Colorado Denver, Aurora
| | - Colleen G Julian
- Division of Bioinformatics and Personalized Medicine, Department of Medicine (C.G.J.), University of Colorado Denver, Aurora
| | - Lorna G Moore
- From the Division of Reproductive Sciences (R.A.L., S.L.L., E.S.B., L.G.M.), University of Colorado Denver, Aurora
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Hu XQ, Zhang L. MicroRNAs in Uteroplacental Vascular Dysfunction. Cells 2019; 8:E1344. [PMID: 31671866 PMCID: PMC6912833 DOI: 10.3390/cells8111344] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 10/26/2019] [Accepted: 10/27/2019] [Indexed: 02/06/2023] Open
Abstract
Pregnancy complications of preeclampsia and intrauterine growth restriction (IUGR) are major causes of maternal and perinatal/neonatal morbidity and mortality. Although their etiologies remain elusive, it is generally accepted that they are secondary to placental insufficiency conferred by both failure in spiral artery remodeling and uteroplacental vascular malfunction. MicroRNAs (miRNAs) are small no-coding RNA molecules that regulate gene expression at the post-transcriptional level. Increasing evidence suggests that miRNAs participate in virtually all biological processes and are involved in numerous human diseases. Differentially expressed miRNAs in the placenta are typical features of both preeclampsia and IUGR. Dysregulated miRNAs target genes of various signaling pathways in uteroplacental tissues, contributing to the development of both complications. In this review, we provide an overview of how aberrant miRNA expression in preeclampsia and IUGR impacts the expression of genes involved in trophoblast invasion and uteroplacental vascular adaptation.
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Affiliation(s)
- Xiang-Qun Hu
- Lawrence D. Longo MD Center for Perinatal Biology, Division of Pharmacology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, California 92350, USA.
| | - Lubo Zhang
- Lawrence D. Longo MD Center for Perinatal Biology, Division of Pharmacology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, California 92350, USA.
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Ertl R, Waldhoer T, Yang L. Moderate altitude impacts birth weight: 30 years retrospective sibling analyses using record linkage data. Pediatr Res 2019; 86:403-407. [PMID: 31112991 DOI: 10.1038/s41390-019-0434-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Revised: 04/09/2019] [Accepted: 05/06/2019] [Indexed: 11/09/2022]
Abstract
OBJECTIVE We investigated the effect of a change of altitude of maternal living address on infant birth weight. METHOD Data on infant birth weights of the first and second pregnancies from same women were extracted from all Austrian birth certificates between 1984 and 2016. RESULTS A total of 544,624 pair pregnancies were identified and analyzed. We observed a statistically significant interaction (p < .0001) between altitudes of two births and birth weight. Among women having first birth at low altitude (200 m), the estimated second mean birth weight was 3567 g for those remained at low altitudes, and reduced to 3536 g for those ascended (1200 m). In contrast, among women having first births at high altitudes, the estimated birth weight of second birth at high altitude was 3414 g, yet increased to 3499 g compared to those descended to lower altitudes. CONCLUSION We demonstrated a longitudinal negative effect of altitude on birth weight within the same mother from first and second birth. This association is likely to be casual. Relocation of mothers within low-to-medium altitude level may have profound effects on infants' birth weight.
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Affiliation(s)
| | - Thomas Waldhoer
- Department of Epidemiology, Center for Public Health, Medical University of Vienna, Vienna, Austria.
| | - Lin Yang
- Department of Epidemiology, Center for Public Health, Medical University of Vienna, Vienna, Austria.,Cancer Epidemiology and Prevention Research, CancerControl Alberta, Alberta Health Services, Calgary, AL, Canada.,Departments of Oncology & Community Health Sciences, University of Calgary, Calgary, AL, Canada
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Lane SL, Dodson RB, Doyle AS, Park H, Rathi H, Matarrazo CJ, Moore LG, Lorca RA, Wolfson GH, Julian CG. Pharmacological activation of peroxisome proliferator-activated receptor γ (PPAR-γ) protects against hypoxia-associated fetal growth restriction. FASEB J 2019; 33:8999-9007. [PMID: 31039323 PMCID: PMC6662983 DOI: 10.1096/fj.201900214r] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Accepted: 04/08/2019] [Indexed: 12/11/2022]
Abstract
The hypoxia of high-altitude (HA) residence increases the risk of intrauterine growth restriction (IUGR) and preeclampsia 3-fold, augmenting perinatal morbidity and mortality and the risk for childhood and adult disease. Currently, no effective therapies exist to prevent these vascular disorders of pregnancy. The peroxisome proliferator-activated receptor γ (PPAR-γ) is an important regulator of uteroplacental vascular development and function and has been implicated in the pathogenesis of IUGR and preeclampsia. Here, we used a model of HA pregnancy in mice to determine whether hypoxia-induced fetal growth restriction reduces placental PPAR-γ protein expression and placental vascularization and, if so, to evaluate the effectiveness of the selective PPAR-γ agonist pioglitazone (PIO) for preventing hypoxia-induced IUGR. Hypoxia resulted in asymmetric IUGR, placental insufficiency, and reduced placental PPAR-γ expression; PIO prevented approximately half of the fetal growth restriction and attenuated placental insufficiency. PIO did not affect fetal growth under normoxia. Although PIO was beneficial for fetal growth, PIO treatment reduced placental vascular density of the labrynthine zone in normoxic and hypoxic (Hx) conditions, and mean vascular area was reduced in the Hx group. Our results suggest that pharmacological PPAR-γ activation is a potential strategy for preventing IUGR in pregnancies complicated by hypoxia, although further studies are needed to identify its likely metabolic or vascular mechanisms.-Lane, S. L., Dodson, R. B., Doyle, A. S., Park, H., Rathi, H., Matarrazo, C. J., Moore, L. G., Lorca, R. A., Wolfson, G. H., Julian, C. G. Pharmacological activation of peroxisome proliferator-activated receptor γ (PPAR-γ) protects against hypoxia-associated fetal growth restriction.
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Affiliation(s)
- Sydney L. Lane
- Integrated Physiology Program, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - R. Blair Dodson
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Alexandrea S. Doyle
- Department of Integrative Biology, University of Colorado Denver, Denver, Colorado, USA
| | - Haemin Park
- Colorado Undergraduate Research in Environmental Health Sciences, University of Colorado Denver, Denver, Colorado, USA
| | - Hinal Rathi
- Department of Integrative Biology, University of Colorado Denver, Denver, Colorado, USA
| | | | - Lorna G. Moore
- Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Ramón A. Lorca
- Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Gabriel H. Wolfson
- Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado, USA; and
| | - Colleen G. Julian
- Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado, USA; and
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Abstract
Complications of pregnancy remain key drivers of morbidity and mortality, affecting the health of both the mother and her offspring in the short and long term. There is lack of detailed understanding of the pathways involved in the pathology and pathogenesis of compromised pregnancy, as well as a shortfall of effective prognostic, diagnostic and treatment options. In many complications of pregnancy, such as in preeclampsia, there is an increase in uteroplacental vascular resistance. However, the cause and effect relationship between placental dysfunction and adverse outcomes in the mother and her offspring remains uncertain. In this review, we aim to highlight the value of gestational hypoxia-induced complications of pregnancy in elucidating underlying molecular pathways and in assessing candidate therapeutic options for these complex disorders. Chronic maternal hypoxia not only mimics the placental pathology associated with obstetric syndromes like gestational hypertension at morphological, molecular and functional levels, but also recapitulates key symptoms that occur as maternal and fetal clinical manifestations of these pregnancy disorders. We propose that gestational hypoxia provides a useful model to study the inter-relationship between placental dysfunction and adverse outcomes in the mother and her offspring in a wide array of examples of complicated pregnancy, such as in preeclampsia.
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[Potential value of placental angiogenic factors as biomarkers in preeclampsia for clinical physicians]. Nephrol Ther 2019; 15:413-429. [PMID: 30935786 DOI: 10.1016/j.nephro.2018.10.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 10/10/2018] [Accepted: 10/14/2018] [Indexed: 12/20/2022]
Abstract
The role of angiogenic factors in the onset of clinical manifestations of preeclampsia was demonstrated in 2003 by the implication of sFlt-1, PlGF and VEGF, and in 2006 by the implication of soluble endoglin. Placental ischemia and inflammation observed in preeclampsia alter both the production and progression of angiogenic factors during pregnancy. During the first trimester, the combination of PlGF with clinical, biophysical and biological factors results in a better test than the conventional one. However, the clinical value of this method remains to be confirmed. During the second and third trimesters, the sFlt-1/PlGF ratio may be used, with or without pre-existing renal disease, for short-term prediction, diagnosis, and prognosis, and to evaluate the effectiveness of preeclampsia treatment. While a sFlt-1/PlGF ratio<38 and≤33, respectively, rules out the short-term onset and diagnosis of preeclampsia, a sFlt-1/PlGF ratio≥85 between 20 and 34 weeks of pregnancy and≥110 beyond 34 weeks of pregnancy confirms a diagnosis of preeclampsia. Angiogenic and non-angiogenic preeclampsia are identified by a sFlt-1PlGF≥85 and<85, respectively, with the risk of maternal and fetal complications at two weeks differing between the two. Similarly, a sFlt-1/PlGF ratio>665 and>205, respectively, is a good short-term predictor of adverse outcomes of early and late-onset preeclampsia. These values could be incorporated into future guidelines for better clinical management of preeclampsia.
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Human Genetic Adaptation to High Altitude: Evidence from the Andes. Genes (Basel) 2019; 10:genes10020150. [PMID: 30781443 PMCID: PMC6410003 DOI: 10.3390/genes10020150] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 01/29/2019] [Accepted: 02/11/2019] [Indexed: 12/31/2022] Open
Abstract
Whether Andean populations are genetically adapted to high altitudes has long been of interest. Initial studies focused on physiological changes in the O₂ transport system that occur with acclimatization in newcomers and their comparison with those of long-resident Andeans. These as well as more recent studies indicate that Andeans have somewhat larger lung volumes, narrower alveolar to arterial O₂ gradients, slightly less hypoxic pulmonary vasoconstrictor response, greater uterine artery blood flow during pregnancy, and increased cardiac O2 utilization, which overall suggests greater efficiency of O₂ transfer and utilization. More recent single nucleotide polymorphism and whole-genome sequencing studies indicate that multiple gene regions have undergone recent positive selection in Andeans. These include genes involved in the regulation of vascular control, metabolic hemostasis, and erythropoiesis. However, fundamental questions remain regarding the functional links between these adaptive genomic signals and the unique physiological attributes of highland Andeans. Well-designed physiological and genome association studies are needed to address such questions. It will be especially important to incorporate the role of epigenetic processes (i.e.; non-sequence-based features of the genome) that are vital for transcriptional responses to hypoxia and are potentially heritable across generations. In short, further exploration of the interaction among genetic, epigenetic, and environmental factors in shaping patterns of adaptation to high altitude promises to improve the understanding of the mechanisms underlying human adaptive potential and clarify its implications for human health.
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Ma J, Zhang Z, Niu W, Chen J, Guo S, Liu S, Dong Y, Yang Z, Wang W, Song C, Ma J, Pei T. Education, Altitude, and Humidity Can Interactively Explain Spatial Discrepancy and Predict Short Stature in 213,795 Chinese School Children. Front Pediatr 2019; 7:425. [PMID: 31737586 PMCID: PMC6836719 DOI: 10.3389/fped.2019.00425] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 10/04/2019] [Indexed: 01/25/2023] Open
Abstract
Backgrounds and Objectives: The north-south height distinctions in Chinese children suggest that some geographical-climatic factors could determine height variation of short stature. In a national health survey, we aimed to explore the spatial distribution of short stature on city scales, and detect its socio-economic and geographical-climatic factors. Methods: Data on the prevalence of short stature were obtained from a 2014 cross-sectional survey of China (CNSSCH). In total, 213,795 Han Chinese students aged 7-18 years, from 106 cities across 30 provinces, were included. Both China and World Health Organization (WHO) growth references were adopted to define short stature. Results: A spatial clustering was apparent in the distribution of short stature. After multivariable adjustment, altitude and humidity significantly increased the risk of high prevalence in short stature, according to the WHO (odds ratio [OR] = 1.61 and 1.26, 95% confidence interval [CI]: 1.20-2.17 and 1.03-1.54) and China (OR = 1.54 and 1.26; 95% CI: 1.15-2.05 and 1.02-1.55) growth references. Additionally, education significantly decreased the risk of high prevalence in short stature according to the WHO (OR = 0.40; 95% CI: 0.22-0.74) and China (OR = 0.42; 95% CI: 0.22-0.77) growth references. Combining both altitude >400 m and education <9 years, as well as education <9 years and humidity >70%, received the largest effect-size estimate, and significance retained after multivariable adjustment. Conclusions: Our findings indicate that high altitude and humidity increased the risk of high prevalence in short stature, high education was associated with low prevalence. Additionally, we observed possible interactions between education and altitude/humidity. They may interactively explain spatial discrepancy and predict short stature in Chinese school children. Further validations are necessary.
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Affiliation(s)
- Jia Ma
- Graduate School, Beijing University of Chinese Medicine, Beijing, China.,Department of Pediatrics, China-Japan Friendship Hospital, Beijing, China
| | - Zhixin Zhang
- Department of Pediatrics, China-Japan Friendship Hospital, Beijing, China
| | - Wenquan Niu
- Institute of Clinical Medical Sciences, China-Japan Friendship Hospital, Beijing, China
| | - Jie Chen
- State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Sihui Guo
- State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Shufang Liu
- Graduate School, Beijing University of Chinese Medicine, Beijing, China.,Department of Pediatrics, China-Japan Friendship Hospital, Beijing, China
| | - Yanhui Dong
- Institute of Child and Adolescent Health and School of Public Health, Peking University, Beijing, China
| | - Zhaogeng Yang
- Institute of Child and Adolescent Health and School of Public Health, Peking University, Beijing, China
| | - Wenlai Wang
- State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Ci Song
- State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Jun Ma
- Institute of Child and Adolescent Health and School of Public Health, Peking University, Beijing, China
| | - Tao Pei
- State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
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Euser AG, Hammes A, Ahrendsen JT, Neshek B, Weitzenkamp DA, Gutierrez J, Koivunen P, Julian CG, Moore LG. Gestational Diabetes Prevalence at Moderate and High Altitude. High Alt Med Biol 2018; 19:367-372. [PMID: 30281336 DOI: 10.1089/ham.2018.0012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND High-altitude (HA) pregnancies have been associated with decreased glucose levels and increased insulin sensitivity versus sea level. Our objective was to determine if the prevalence of gestational diabetes mellitus (GDM) and the impact of demographic characteristics on GDM diagnosis differed at moderate altitude (MA) versus HA. METHODS Using a retrospective cohort design, we compared women living at HA (>8250 ft) and MA (4000-7000 ft) during pregnancy. Exclusion criteria were as follows: multiple gestation, preexisting diabetes, unavailable GDM results, or relocation from a different altitude during pregnancy. GDM diagnosis was determined using Carpenter and Coustan criteria. Data were compared by t-test (continuous variables) or chi-squared tests (categorical variables). Univariate, multivariate, and stepwise regression models were used to assess the impact of various factors on GDM prevalence. RESULTS There was no difference in GDM prevalence between altitudes in these populations; the relationship between altitude and GDM was nonsignificant in all regression analyses. At MA, maternal age, Hispanic ethnicity, body mass index (BMI), and gestational age (GA) at testing increased GDM incidence in univariate analyses. At HA, maternal age, Hispanic ethnicity, and multiparity increased GDM incidence in univariate analyses. CONCLUSION While GDM prevalence did not differ between MA and HA, the impact of maternal demographic characteristics on GDM risk varied by altitude group. Higher BMI and greater GA at testing increased the incidence of GDM at MA, but not at HA. Multiparity had an effect at HA, but not MA. These differences may represent subtle differences in glucose metabolism at HA.
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Affiliation(s)
- Anna G Euser
- 1 Department of Obstetrics and Gynecology, University of Colorado Denver School of Medicine , Aurora, Colorado
| | - Andrew Hammes
- 2 Department of Biostatistics and Informatics, University of Colorado , Aurora, Colorado
| | - Jared T Ahrendsen
- 3 University of Colorado Denver School of Medicine , Aurora, Colorado
| | - Barbara Neshek
- 3 University of Colorado Denver School of Medicine , Aurora, Colorado
| | - David A Weitzenkamp
- 2 Department of Biostatistics and Informatics, University of Colorado , Aurora, Colorado
| | | | - Peppi Koivunen
- 5 Biocenter Oulu, Faculty of Biochemistry and Molecular Medicine, Oulu Center for Cell-Matrix Research, University of Oulu , Oulu, Finland
| | - Colleen G Julian
- 6 Department of Medicine, University of Colorado Denver School of Medicine , Aurora, Colorado
| | - Lorna G Moore
- 1 Department of Obstetrics and Gynecology, University of Colorado Denver School of Medicine , Aurora, Colorado
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Post-translational modifications of eNOS augment nitric oxide availability and facilitates hypoxia adaptation in Ladakhi women. Nitric Oxide 2018; 78:103-112. [DOI: 10.1016/j.niox.2018.06.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 05/31/2018] [Accepted: 06/05/2018] [Indexed: 12/22/2022]
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40
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Zhang P, Ke J, Li Y, Huang L, Chen Z, Huang X, Zhang L, Xiao D. Long-term exposure to high altitude hypoxia during pregnancy increases fetal heart susceptibility to ischemia/reperfusion injury and cardiac dysfunction. Int J Cardiol 2018; 274:7-15. [PMID: 30017521 DOI: 10.1016/j.ijcard.2018.07.046] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 06/15/2018] [Accepted: 07/06/2018] [Indexed: 01/19/2023]
Abstract
BACKGROUND High altitude hypoxia (HAH) exposure affects fetal development. However, the fetal cardiovascular responses to the HAH are not well understood. We have tested the hypothesis that long-term HAH exposure alters the hypoxia/ischemia-sensitive gene expressions, leading to an increase in fetal heart susceptibility to ischemia/reperfusion (I/R) injury and cardiac dysfunction. METHODS Time-dated pregnant sheep were exposed to high-altitude (3820 m) or were maintained at sea level (~300 m) for 110 days. Fetal hearts were isolated from the near-term ewes and subjected to I/R in a Langendorff preparation. RESULTS HAH decreased the fetal body and heart weights in the female but not male fetuses. HAH had no effect on the left ventricle (LV) function at baseline, but increased the LV infarct size and attenuated the post-ischemic recovery of LV function in both male and female fetuses, as compared with the normoxic groups. HAH increased the protein levels of hypoxia-inducible factor (HIF)-1α and DNA methyltransferases type 3b (DNMT3b), but attenuated protein kinase C epsilon (PKCε) levels in the fetal hearts. AHA induced a 4.3 fold increase of miR-210 in the males and a 2.9 fold increase in female hearts. In addition, HAH had no effect on mTOR protein and phosphorylation levels but increased the autophagy biomarker, LC3B-II protein levels and LC3B-II/LC3B-I ratio in the fetal hearts. CONCLUSION The results suggest that gestational HAH exposure induces in utero programming of the hypoxia/ischemia-sensitive gene expression pattern in the developing heart and increases cardiac susceptibility to I/R injury.
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Affiliation(s)
- Peng Zhang
- Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA, USA; The First Affiliated Hospital, Chongqing Medical University, Chongqing, China
| | - Jun Ke
- Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA, USA; Guangdong Cardiovascular Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Yong Li
- Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA, USA
| | - Lei Huang
- Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA, USA
| | - Zewen Chen
- Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA, USA; Guangdong Cardiovascular Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Xiaohui Huang
- Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA, USA
| | - Lubo Zhang
- Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA, USA
| | - Daliao Xiao
- Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA, USA.
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Ducsay CA, Goyal R, Pearce WJ, Wilson S, Hu XQ, Zhang L. Gestational Hypoxia and Developmental Plasticity. Physiol Rev 2018; 98:1241-1334. [PMID: 29717932 PMCID: PMC6088145 DOI: 10.1152/physrev.00043.2017] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Hypoxia is one of the most common and severe challenges to the maintenance of homeostasis. Oxygen sensing is a property of all tissues, and the response to hypoxia is multidimensional involving complicated intracellular networks concerned with the transduction of hypoxia-induced responses. Of all the stresses to which the fetus and newborn infant are subjected, perhaps the most important and clinically relevant is that of hypoxia. Hypoxia during gestation impacts both the mother and fetal development through interactions with an individual's genetic traits acquired over multiple generations by natural selection and changes in gene expression patterns by altering the epigenetic code. Changes in the epigenome determine "genomic plasticity," i.e., the ability of genes to be differentially expressed according to environmental cues. The genomic plasticity defined by epigenomic mechanisms including DNA methylation, histone modifications, and noncoding RNAs during development is the mechanistic substrate for phenotypic programming that determines physiological response and risk for healthy or deleterious outcomes. This review explores the impact of gestational hypoxia on maternal health and fetal development, and epigenetic mechanisms of developmental plasticity with emphasis on the uteroplacental circulation, heart development, cerebral circulation, pulmonary development, and the hypothalamic-pituitary-adrenal axis and adipose tissue. The complex molecular and epigenetic interactions that may impact an individual's physiology and developmental programming of health and disease later in life are discussed.
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Affiliation(s)
- Charles A. Ducsay
- The Lawrence D. Longo, MD Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, California
| | - Ravi Goyal
- The Lawrence D. Longo, MD Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, California
| | - William J. Pearce
- The Lawrence D. Longo, MD Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, California
| | - Sean Wilson
- The Lawrence D. Longo, MD Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, California
| | - Xiang-Qun Hu
- The Lawrence D. Longo, MD Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, California
| | - Lubo Zhang
- The Lawrence D. Longo, MD Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, California
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Lineker C, Kerr PM, Nguyen P, Bloor I, Astbury S, Patel N, Budge H, Hemmings DG, Plane F, Symonds ME, Bell RC. High fructose consumption in pregnancy alters the perinatal environment without increasing metabolic disease in the offspring. Reprod Fertil Dev 2018; 28:2007-2015. [PMID: 26143929 DOI: 10.1071/rd15119] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 06/04/2015] [Indexed: 12/12/2022] Open
Abstract
Maternal carbohydrate intake is one important determinant of fetal body composition, but whether increased exposure to individual sugars has long-term adverse effects on the offspring is not well established. Therefore, we examined the effect of fructose feeding on the mother, placenta, fetus and her offspring up to 6 months of life when they had been weaned onto a standard rodent diet and not exposed to additional fructose. Dams fed fructose were fatter, had raised plasma insulin and triglycerides from mid-gestation and higher glucose near term. Maternal resistance arteries showed changes in function that could negatively affect regulation of blood pressure and tissue perfusion in the mother and development of the fetus. Fructose feeding had no effect on placental weight or fetal metabolic profiles, but placental gene expression for the glucose transporter GLUT1 was reduced, whereas the abundance of sodium-dependent neutral amino acid transporter-2 was raised. Offspring born to fructose-fed and control dams were similar at birth and had similar post-weaning growth rates, and neither fat mass nor metabolic profiles were affected. In conclusion, raised fructose consumption during reproduction results in pronounced maternal metabolic and vascular effects, but no major detrimental metabolic effects were observed in offspring up to 6 months of age.
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Affiliation(s)
- Christopher Lineker
- Division of Human Nutrition, Department of Agricultural, Food and Nutritional Sciences, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Paul M Kerr
- Department of Pharmacology, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Patricia Nguyen
- Department of Pharmacology, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Ian Bloor
- Early Life Research Group, Academic Division of Child Health, Obstetrics and Gynaecology, School of Medicine, Queen's Medical Centre, University Hospital, The University of Nottingham, Nottingham NG7 2UH, UK
| | - Stuart Astbury
- Division of Human Nutrition, Department of Agricultural, Food and Nutritional Sciences, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Nikhil Patel
- Division of Human Nutrition, Department of Agricultural, Food and Nutritional Sciences, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Helen Budge
- Early Life Research Group, Academic Division of Child Health, Obstetrics and Gynaecology, School of Medicine, Queen's Medical Centre, University Hospital, The University of Nottingham, Nottingham NG7 2UH, UK
| | - Denise G Hemmings
- Department of Obstetrics and Gynecology, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Frances Plane
- Department of Pharmacology, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Michael E Symonds
- Early Life Research Group, Academic Division of Child Health, Obstetrics and Gynaecology, School of Medicine, Queen's Medical Centre, University Hospital, The University of Nottingham, Nottingham NG7 2UH, UK
| | - Rhonda C Bell
- Division of Human Nutrition, Department of Agricultural, Food and Nutritional Sciences, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
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He Y, Qi X, Ouzhuluobu, Liu S, Li J, Zhang H, Baimakangzhuo, Bai C, Zheng W, Guo Y, Duojizhuoma, Baimayangji, Dejiquzong, Bianba, Gonggalanzi, Pan Y, Qula, Kangmin, Cirenyangji, Guo W, Yangla, Peng Y, Zhang X, Xiang K, Yang Z, Wang L, Gengdeng, Zhang Y, Wu T, Su B, Cui C. Blunted nitric oxide regulation in Tibetans under high-altitude hypoxia. Natl Sci Rev 2018. [DOI: 10.1093/nsr/nwy037] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
ABSTRACT
Nitric oxide (NO) is an important molecule for vasomotor tone, and elevated NO signaling was previously hypothesized as a unique and adaptive physiological change in highland Tibetans. However, there has been lack of NO data from Tibetans living at low altitude and lowlander immigrants living at high altitude, which is crucial to test this hypothesis. Here, through cross-altitude (1990–5018 m) and cross-population (Tibetans and Han Chinese) analyses of serum NO metabolites (NOx) of 2086 individuals, we demonstrate that although Tibetans have a higher serum NOx level compared to lowlanders, Han Chinese immigrants living at high altitude show an even higher level than Tibetans. Consequently, our data contradict the previous proposal of increased NO signaling as the unique adaptive strategy in Tibetans. Instead, Tibetans have a relatively lower circulating NOx level at high altitude. This observation is further supported by data from the hypoxic experiments using human umbilical vein endothelial cells and gene knockout mice. No difference is detected between Tibetans and Han Chinese for endothelial nitric oxide synthase (eNOS), the key enzyme for circulating NO synthesis, suggesting that eNOS itself is unlikely to be the cause. We show that other NO synthesis-related genes (e.g. GCH1) carry Tibetan-enriched mutations significantly associated with the level of circulating NOx in Tibetans. Furthermore, gene network analysis revealed that the downregulation and upregulation of NOx is possibly achieved through distinct pathways. Collectively, our findings provide novel insights into the physiological and genetic mechanisms of the evolutionary adaptation of Tibetans to high-altitude hypoxia.
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Affiliation(s)
- Yaoxi He
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Beijing 100101, China
- Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming 650223, China
| | - Xuebin Qi
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
- Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming 650223, China
| | - Ouzhuluobu
- High Altitude Medical Research Center, School of Medicine, Tibetan University, Lhasa 850000, China
| | - Shiming Liu
- National Key Laboratory of High Altitude Medicine, High Altitude Medical Research Institute, Xining 810012, China
| | - Jun Li
- Fukang International Medical Examination Center, Fukang Obstetrics, Gynecology and Children Branch Hospital, Tibetan Fukang Hospital, Lhasa 850000, China
| | - Hui Zhang
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
- High Altitude Medical Research Center, School of Medicine, Tibetan University, Lhasa 850000, China
| | - Baimakangzhuo
- High Altitude Medical Research Center, School of Medicine, Tibetan University, Lhasa 850000, China
| | - Caijuan Bai
- High Altitude Medical Research Center, School of Medicine, Tibetan University, Lhasa 850000, China
| | - Wangshan Zheng
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
| | - Yongbo Guo
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
| | - Duojizhuoma
- High Altitude Medical Research Center, School of Medicine, Tibetan University, Lhasa 850000, China
| | - Baimayangji
- High Altitude Medical Research Center, School of Medicine, Tibetan University, Lhasa 850000, China
| | - Dejiquzong
- High Altitude Medical Research Center, School of Medicine, Tibetan University, Lhasa 850000, China
| | - Bianba
- High Altitude Medical Research Center, School of Medicine, Tibetan University, Lhasa 850000, China
| | - Gonggalanzi
- High Altitude Medical Research Center, School of Medicine, Tibetan University, Lhasa 850000, China
| | - Yongyue Pan
- High Altitude Medical Research Center, School of Medicine, Tibetan University, Lhasa 850000, China
| | - Qula
- High Altitude Medical Research Center, School of Medicine, Tibetan University, Lhasa 850000, China
| | - Kangmin
- High Altitude Medical Research Center, School of Medicine, Tibetan University, Lhasa 850000, China
| | - Cirenyangji
- High Altitude Medical Research Center, School of Medicine, Tibetan University, Lhasa 850000, China
| | - Wei Guo
- High Altitude Medical Research Center, School of Medicine, Tibetan University, Lhasa 850000, China
| | - Yangla
- High Altitude Medical Research Center, School of Medicine, Tibetan University, Lhasa 850000, China
| | - Yi Peng
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
| | - Xiaoming Zhang
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
| | - Kun Xiang
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
| | - Zhaohui Yang
- Yunnan Key Laboratory of Primate Biomedicine Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming 650500, China
| | - Liangbang Wang
- National Key Laboratory of High Altitude Medicine, High Altitude Medical Research Institute, Xining 810012, China
| | - Gengdeng
- National Key Laboratory of High Altitude Medicine, High Altitude Medical Research Institute, Xining 810012, China
| | - Yanfeng Zhang
- Fukang International Medical Examination Center, Fukang Obstetrics, Gynecology and Children Branch Hospital, Tibetan Fukang Hospital, Lhasa 850000, China
| | - Tianyi Wu
- National Key Laboratory of High Altitude Medicine, High Altitude Medical Research Institute, Xining 810012, China
| | - Bing Su
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
- Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming 650223, China
| | - Chaoying Cui
- High Altitude Medical Research Center, School of Medicine, Tibetan University, Lhasa 850000, China
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44
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Moore LG. Measuring high-altitude adaptation. J Appl Physiol (1985) 2017; 123:1371-1385. [PMID: 28860167 DOI: 10.1152/japplphysiol.00321.2017] [Citation(s) in RCA: 113] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 08/15/2017] [Accepted: 08/15/2017] [Indexed: 12/12/2022] Open
Abstract
High altitudes (>8,000 ft or 2,500 m) provide an experiment of nature for measuring adaptation and the physiological processes involved. Studies conducted over the past ~25 years in Andeans, Tibetans, and, less often, Ethiopians show varied but distinct O2 transport traits from those of acclimatized newcomers, providing indirect evidence for genetic adaptation to high altitude. Short-term (acclimatization, developmental) and long-term (genetic) responses to high altitude exhibit a temporal gradient such that, although all influence O2 content, the latter also improve O2 delivery and metabolism. Much has been learned concerning the underlying physiological processes, but additional studies are needed on the regulation of blood flow and O2 utilization. Direct evidence of genetic adaptation comes from single-nucleotide polymorphism (SNP)-based genome scans and whole genome sequencing studies that have identified gene regions acted upon by natural selection. Efforts have begun to understand the connections between the two with Andean studies on the genetic factors raising uterine blood flow, fetal growth, and susceptibility to Chronic Mountain Sickness and Tibetan studies on genes serving to lower hemoglobin and pulmonary arterial pressure. Critical for future studies will be the selection of phenotypes with demonstrable effects on reproductive success, the calculation of actual fitness costs, and greater inclusion of women among the subjects being studied. The well-characterized nature of the O2 transport system, the presence of multiple long-resident populations, and relevance for understanding hypoxic disorders in all persons underscore the importance of understanding how evolutionary adaptation to high altitude has occurred.NEW & NOTEWORTHY Variation in O2 transport characteristics among Andean, Tibetan, and, when available, Ethiopian high-altitude residents supports the existence of genetic adaptations that improve the distribution of blood flow to vital organs and the efficiency of O2 utilization. Genome scans and whole genome sequencing studies implicate a broad range of gene regions. Future studies are needed using phenotypes of clear relevance for reproductive success for determining the mechanisms by which naturally selected genes are acting.
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Affiliation(s)
- Lorna G Moore
- Division of Reproductive Sciences, Department of Obstetrics & Gynecology, University of Colorado Denver-Anschutz Medical Campus, Aurora, Colorado
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45
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Abstract
Epidemiological evidence links an individual's susceptibility to chronic disease in adult life to events during their intrauterine phase of development. Biologically this should not be unexpected, for organ systems are at their most plastic when progenitor cells are proliferating and differentiating. Influences operating at this time can permanently affect their structure and functional capacity, and the activity of enzyme systems and endocrine axes. It is now appreciated that such effects lay the foundations for a diverse array of diseases that become manifest many years later, often in response to secondary environmental stressors. Fetal development is underpinned by the placenta, the organ that forms the interface between the fetus and its mother. All nutrients and oxygen reaching the fetus must pass through this organ. The placenta also has major endocrine functions, orchestrating maternal adaptations to pregnancy and mobilizing resources for fetal use. In addition, it acts as a selective barrier, creating a protective milieu by minimizing exposure of the fetus to maternal hormones, such as glucocorticoids, xenobiotics, pathogens, and parasites. The placenta shows a remarkable capacity to adapt to adverse environmental cues and lessen their impact on the fetus. However, if placental function is impaired, or its capacity to adapt is exceeded, then fetal development may be compromised. Here, we explore the complex relationships between the placental phenotype and developmental programming of chronic disease in the offspring. Ensuring optimal placentation offers a new approach to the prevention of disorders such as cardiovascular disease, diabetes, and obesity, which are reaching epidemic proportions.
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Affiliation(s)
- Graham J Burton
- Centre for Trophoblast Research and Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom; and Department of Medicine, Knight Cardiovascular Institute, and Moore Institute for Nutrition and Wellness, Oregon Health and Science University, Portland, Oregon
| | - Abigail L Fowden
- Centre for Trophoblast Research and Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom; and Department of Medicine, Knight Cardiovascular Institute, and Moore Institute for Nutrition and Wellness, Oregon Health and Science University, Portland, Oregon
| | - Kent L Thornburg
- Centre for Trophoblast Research and Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom; and Department of Medicine, Knight Cardiovascular Institute, and Moore Institute for Nutrition and Wellness, Oregon Health and Science University, Portland, Oregon
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46
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Aljunaidy MM, Morton JS, Cooke CL, Davidge ST. Maternal vascular responses to hypoxia in a rat model of intrauterine growth restriction. Am J Physiol Regul Integr Comp Physiol 2016; 311:R1068-R1075. [PMID: 27760732 DOI: 10.1152/ajpregu.00119.2016] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 10/06/2016] [Accepted: 10/12/2016] [Indexed: 11/22/2022]
Abstract
Intrauterine growth restriction (IUGR) is a common pregnancy complication and is a leading cause of fetal morbidity and mortality. Placental hypoxia contributes to adverse fetal consequences, such as IUGR. Exposing pregnant rats to hypoxia can lead to IUGR; however, assessment of maternal vascular function in a rat model of hypoxia, and the mechanisms that may contribute to adverse pregnancy outcomes, has not been extensively studied. We hypothesized that exposing pregnant rats to hypoxia will affect maternal systemic vascular function and increase the uterine artery resistance index (RI), which will be associated with IUGR. To test this hypothesis, pregnant rats were kept in normoxia (21% O2) or hypoxia (11% O2) from gestational day (GD) 6 to 20 Maternal blood pressure, uteroplacental resistance index (RI) (ultrasound biomicroscopy), and vascular function (wire myography) were assessed in uterine and mesenteric arteries. Fetal weight was significantly reduced (P < 0.001), while maternal blood pressure was increased (P < 0.05) in rats exposed to hypoxia. Maternal vascular function was also affected after exposure to hypoxia, including impaired endothelium-dependent vasodilation responses to methacholine in isolated uterine arteries (pEC50 normoxia: 6.55 ± 0.23 vs. hypoxia: 5.02 ± 0.35, P < 0.01) and a reduced uterine artery RI in vivo (normoxia: 0.63 ± 0.04 vs. hypoxia: 0.53 ± 0.01, P < 0.05); associated with an increase in umbilical vein RI (normoxia: 0.35 ± 0.02 vs. hypoxia: 0.45 ± 0.04, P < 0.05). These data demonstrate maternal and fetal alterations in vascular function due to prenatal exposure to hypoxia. Further, although there was a compensatory reduction in uterine artery RI in the hypoxia groups, this was not sufficient to prevent IUGR.
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Affiliation(s)
- Mais M Aljunaidy
- Department of Obstetrics and Gynecology, University of Alberta, Alberta, Edmonton, Canada.,Department of Physiology, University of Alberta, Alberta, Edmonton, Canada; and.,Women and Children's Health Research Institute and the Cardiovascular Research Centre, Edmonton, Alberta, Canada
| | - Jude S Morton
- Department of Obstetrics and Gynecology, University of Alberta, Alberta, Edmonton, Canada.,Women and Children's Health Research Institute and the Cardiovascular Research Centre, Edmonton, Alberta, Canada
| | - Christy-Lynn Cooke
- Department of Obstetrics and Gynecology, University of Alberta, Alberta, Edmonton, Canada.,Women and Children's Health Research Institute and the Cardiovascular Research Centre, Edmonton, Alberta, Canada
| | - Sandra T Davidge
- Department of Obstetrics and Gynecology, University of Alberta, Alberta, Edmonton, Canada; .,Department of Physiology, University of Alberta, Alberta, Edmonton, Canada; and.,Women and Children's Health Research Institute and the Cardiovascular Research Centre, Edmonton, Alberta, Canada
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47
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Aksoy AN, Batmaz G, Dane B, Kucur SK, Gözükara İ. Effects of altitude changes on Doppler flow parameters for uterine, umbilical, and mid-cerebral arteries in term pregnancy: A pilot study. J Turk Ger Gynecol Assoc 2015; 16:237-40. [PMID: 26692775 DOI: 10.5152/jtgga.2015.15134] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 06/30/2015] [Indexed: 01/01/2023] Open
Abstract
OBJECTIVE We hypothesized that maternal and fetal circulations may be affected by moderately high altitudes. Therefore, we compared the differences in maternal and fetal Doppler flow parameters in women with term pregnancy living at a moderately high altitude (1890 m in Erzurum) with those of women living at the sea level (31 m in İstanbul). MATERIAL AND METHODS Eighty women (n=40, for each group) with full-term and singleton pregnancies underwent Doppler waveform analysis, and the pulsatility and resistance index values for the uterine, umbilical, and mid-cerebral arteries were recorded. Also, sex, birth, and placental weights during delivery were obtained from the medical records. RESULTS Similar mean placental weight values were found at the sea level compared with the moderately high altitude (p>0.05). The mean birth weight values were found to be lower at the moderately high altitude than those at the sea level (p<0.05). The pulsatility and resistance index values for the umbilical and mid-cerebral arteries were found to be similar between the groups (p>0.05). However, the pulsatility and resistance index values for both the right and left uterine arteries were higher at the sea level than those at moderately high altitude (p<0.05, for all). CONCLUSION Moderately high altitude does not affect fetal vascular Doppler parameters. However, it appears to increase the uterine artery blood flow bilaterally, and these alterations in the bilateral uterine artery blood flow may be associated with a physiological adaptation to high altitude.
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Affiliation(s)
- Ayşe Nur Aksoy
- Department of Obsterics and Gynaecology, Nenehatun Maternity Hospital, Erzurum, Turkey
| | - Gonca Batmaz
- Department of Obstetrics and Gynaecology, Bezmialem Vakif University Faculty of Medicine, İstanbul, Turkey
| | - Banu Dane
- Department of Obstetrics and Gynaecology, Bezmialem Vakif University Faculty of Medicine, İstanbul, Turkey
| | - Suna Kabil Kucur
- Department of Obsterics and Gynaecology, Nenehatun Maternity Hospital, Erzurum, Turkey
| | - İlay Gözükara
- Department of Obsterics and Gynaecology, Nenehatun Maternity Hospital, Erzurum, Turkey
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48
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Pomeroy E, Wells JCK, Stanojevic S, Miranda JJ, Moore LG, Cole TJ, Stock JT. Surname-inferred Andean ancestry is associated with child stature and limb lengths at high altitude in Peru, but not at sea level. Am J Hum Biol 2015; 27:798-806. [PMID: 25960137 PMCID: PMC4607539 DOI: 10.1002/ajhb.22725] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 02/01/2015] [Accepted: 03/09/2015] [Indexed: 12/20/2022] Open
Abstract
OBJECTIVES Native Andean ancestry gives partial protection from reduced birthweight at high altitude in the Andes compared with European ancestry. Whether Andean ancestry is also associated with body proportions and greater postnatal body size at altitude is unknown. Therefore, we tested whether a greater proportion of Andean ancestry is associated with stature and body proportions among Peruvian children at high and low altitude. METHODS Height, head circumference, head-trunk height, upper and lower limb lengths, and tibia, ulna, hand and foot lengths, were measured in 133 highland and 169 lowland children aged 6 months to 8.5 years. For highland and lowland groups separately, age-sex-adjusted anthropometry z scores were regressed on the number of indigenous parental surnames as a proxy for Andean ancestry, adjusting for potential confounders (maternal age and education, parity, altitude [highlands only]). RESULTS Among highland children, greater Andean ancestry was negatively associated with stature and tibia, ulna, and lower limb lengths, independent of negative associations with greater altitude for these measurements. Relationships were strongest for tibia length: each additional Andean surname or 1,000 m increase at altitude among highland children was associated with 0.18 and 0.65 z score decreases in tibia length, respectively. Anthropometry was not significantly associated with ancestry among lowland children. CONCLUSIONS Greater Andean ancestry is associated with shorter stature and limb measurements at high but not low altitude. Gene-environment interactions between high altitude and Andean ancestry may exacerbate the trade-off between chest dimensions and stature that was proposed previously, though we could not test this directly.
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Affiliation(s)
- Emma Pomeroy
- Newnham College, University of Cambridge, Cambridge, United Kingdom
- Division of Biological Anthropology, Department of Archaeology and Anthropology, University of Cambridge, United Kingdom
| | - Jonathan C K Wells
- Division of Biological Anthropology, Department of Archaeology and Anthropology, University of Cambridge, United Kingdom
- Childhood Nutrition Research Centre, UCL Institute of Child Health, University College London, London, United Kingdom
| | - Sanja Stanojevic
- Division of Respiratory Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - J Jaime Miranda
- CRONICAS Center of Excellence in Chronic Diseases and Department of Medicine, School of Medicine, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Lorna G Moore
- Department of Obstetrics/Gynecology, University of Colorado Denver, Aurora, Colorado
| | - Tim J Cole
- Population, Policy and Practice Programme, UCL Institute of Child Health, University College London, United Kingdom
| | - Jay T Stock
- Division of Biological Anthropology, Department of Archaeology and Anthropology, University of Cambridge, United Kingdom
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49
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Abstract
Doppler ultrasonography plays an ever-increasing role in obstetric imaging. Although commonly purported to assess blood flow, most studies in this area report purely on velocimetric parameters, rather than true volumetric flow. This review article highlights the physiological importance of this distinction, and reports on a literature review of uterine artery Doppler interrogation in the context of pre-eclampsia, which identified only four original research papers that attempted to assess blood flow. Attention is needed for true volumetric flow assessment in pre-eclampsia research, which may permit a more complete conceptualisation of the pathogenesis and haemodynamic consequences of this condition.
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Affiliation(s)
- Stefan C Kane
- a Department of Perinatal Medicine , The Royal Women's Hospital , Parkville , Victoria , Australia .,b Department of Obstetrics and Gynaecology , The University of Melbourne , Melbourne , Victoria , Australia
| | - Alicia T Dennis
- b Department of Obstetrics and Gynaecology , The University of Melbourne , Melbourne , Victoria , Australia .,c Department of Anaesthesia , The Royal Women's Hospital , Parkville , Victoria , Australia , and.,d Department of Pharmacology , The University of Melbourne , Melbourne , Victoria , Australia
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50
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Skeffington KL, Higgins JS, Mahmoud AD, Evans AM, Sferruzzi-Perri AN, Fowden AL, Yung HW, Burton GJ, Giussani DA, Moore LG. Hypoxia, AMPK activation and uterine artery vasoreactivity. J Physiol 2015; 594:1357-69. [PMID: 26110512 DOI: 10.1113/jp270995] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 06/21/2015] [Indexed: 01/12/2023] Open
Abstract
Genes near adenosine monophosphate-activated protein kinase-α1 (PRKAA1) have been implicated in the greater uterine artery (UtA) blood flow and relative protection from fetal growth restriction seen in altitude-adapted Andean populations. Adenosine monophosphate-activated protein kinase (AMPK) activation vasodilates multiple vessels but whether AMPK is present in UtA or placental tissue and influences UtA vasoreactivity during normal or hypoxic pregnancy remains unknown. We studied isolated UtA and placenta from near-term C57BL/6J mice housed in normoxia (n = 8) or hypoxia (10% oxygen, n = 7-9) from day 14 to day 19, and placentas from non-labouring sea level (n = 3) or 3100 m (n = 3) women. Hypoxia increased AMPK immunostaining in near-term murine UtA and placental tissue. RT-PCR products for AMPK-α1 and -α2 isoforms and liver kinase B1 (LKB1; the upstream kinase activating AMPK) were present in murine and human placenta, and hypoxia increased LKB1 and AMPK-α1 and -α2 expression in the high- compared with low-altitude human placentas. Pharmacological AMPK activation by A769662 caused phenylephrine pre-constricted UtA from normoxic or hypoxic pregnant mice to dilate and this dilatation was partially reversed by the NOS inhibitor l-NAME. Hypoxic pregnancy sufficient to restrict fetal growth markedly augmented the UtA vasodilator effect of AMPK activation in opposition to PE constriction as the result of both NO-dependent and NO-independent mechanisms. We conclude that AMPK is activated during hypoxic pregnancy and that AMPK activation vasodilates the UtA, especially in hypoxic pregnancy. AMPK activation may be playing an adaptive role by limiting cellular energy depletion and helping to maintain utero-placental blood flow in hypoxic pregnancy.
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Affiliation(s)
- K L Skeffington
- Centre for Trophoblast Research, Department of Physiology Development & Neuroscience, University of Cambridge, Cambridge, UK
| | - J S Higgins
- Centre for Trophoblast Research, Department of Physiology Development & Neuroscience, University of Cambridge, Cambridge, UK
| | - A D Mahmoud
- Centre for Integrative Physiology, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, UK
| | - A M Evans
- Centre for Integrative Physiology, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, UK
| | - A N Sferruzzi-Perri
- Centre for Trophoblast Research, Department of Physiology Development & Neuroscience, University of Cambridge, Cambridge, UK
| | - A L Fowden
- Centre for Trophoblast Research, Department of Physiology Development & Neuroscience, University of Cambridge, Cambridge, UK
| | - H W Yung
- Centre for Trophoblast Research, Department of Physiology Development & Neuroscience, University of Cambridge, Cambridge, UK
| | - G J Burton
- Centre for Trophoblast Research, Department of Physiology Development & Neuroscience, University of Cambridge, Cambridge, UK
| | - D A Giussani
- Centre for Trophoblast Research, Department of Physiology Development & Neuroscience, University of Cambridge, Cambridge, UK
| | - L G Moore
- Division of Basic Reproductive Sciences, Department of Obstetrics & Gynaecology, University of Colorado Denver, Aurora, CO, USA
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