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Fulghum KL, Collins HE, Lorkiewicz PK, Cassel TA, Fan TWM, Hill BG. Exercise-induced changes in myocardial glucose utilization during periods of active cardiac growth. J Mol Cell Cardiol 2024; 191:50-62. [PMID: 38703412 DOI: 10.1016/j.yjmcc.2024.04.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 04/08/2024] [Accepted: 04/26/2024] [Indexed: 05/06/2024]
Abstract
Exercise training can promote physiological cardiac growth, which has been suggested to involve changes in glucose metabolism to facilitate hypertrophy of cardiomyocytes. In this study, we used a dietary, in vivo isotope labeling approach to examine how exercise training influences the metabolic fate of carbon derived from dietary glucose in the heart during acute, active, and established phases of exercise-induced cardiac growth. Male and female FVB/NJ mice were subjected to treadmill running for up to 4 weeks and cardiac growth was assessed by gravimetry. Cardiac metabolic responses to exercise were assessed via in vivo tracing of [13C6]-glucose via mass spectrometry and nuclear magnetic resonance. We found that the half-maximal cardiac growth response was achieved by approximately 1 week of daily exercise training, with near maximal growth observed in male mice with 2 weeks of training; however, female mice were recalcitrant to exercise-induced cardiac growth and required a higher daily intensity of exercise training to achieve significant, albeit modest, increases in cardiac mass. We also found that increases in the energy charge of adenylate and guanylate nucleotide pools precede exercise-induced changes in cardiac size and were associated with higher glucose tracer enrichment in the TCA pool and in amino acids (aspartate, glutamate) sourced by TCA intermediates. Our data also indicate that the activity of collateral biosynthetic pathways of glucose metabolism may not be markedly altered by exercise. Overall, this study provides evidence that metabolic remodeling in the form of heightened energy charge and increased TCA cycle activity and cataplerosis precedes cardiac growth caused by exercise training in male mice.
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Affiliation(s)
- Kyle L Fulghum
- Center for Cardiometabolic Science, Christina Lee Brown Envirome Institute, Division of Environmental Medicine, Department of Medicine, University of Louisville, Louisville, KY, United States of America
| | - Helen E Collins
- Center for Cardiometabolic Science, Christina Lee Brown Envirome Institute, Division of Environmental Medicine, Department of Medicine, University of Louisville, Louisville, KY, United States of America
| | - Pawel K Lorkiewicz
- Center for Cardiometabolic Science, Christina Lee Brown Envirome Institute, Division of Environmental Medicine, Department of Medicine, University of Louisville, Louisville, KY, United States of America
| | - Teresa A Cassel
- Center for Environmental and Systems Biochemistry, University of Kentucky, Lexington, KY, United States of America
| | - Teresa W M Fan
- Center for Environmental and Systems Biochemistry, University of Kentucky, Lexington, KY, United States of America
| | - Bradford G Hill
- Center for Cardiometabolic Science, Christina Lee Brown Envirome Institute, Division of Environmental Medicine, Department of Medicine, University of Louisville, Louisville, KY, United States of America.
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Schulman-Geltzer EB, Fulghum KL, Singhal RA, Hill BG, Collins HE. Cardiac mitochondrial metabolism during pregnancy and the postpartum period. Am J Physiol Heart Circ Physiol 2024; 326:H1324-H1335. [PMID: 38551485 DOI: 10.1152/ajpheart.00127.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 03/20/2024] [Accepted: 03/26/2024] [Indexed: 05/02/2024]
Abstract
The goal of the present study was to characterize changes in mitochondrial respiration in the maternal heart during pregnancy and after birth. Timed pregnancy studies were performed in 12-wk-old female FVB/NJ mice, and cardiac mitochondria were isolated from the following groups of mice: nonpregnant (NP), midpregnancy (MP), late pregnancy (LP), and 1-wk postbirth (PB). Similar to our previous studies, we observed increased heart size during all stages of pregnancy (e.g., MP and LP) and postbirth (e.g., PB) compared with NP mice. Differential cardiac gene and protein expression analyses revealed changes in several mitochondrial transcripts at LP and PB, including several mitochondrial complex subunits and members of the Slc family, important for mitochondrial substrate transport. Respirometry revealed that pyruvate- and glutamate-supported state 3 respiration was significantly higher in PB vs. LP mitochondria, with respiratory control ratio (RCR) values higher in PB mitochondria. In addition, we found that PB mitochondria respired more avidly when given 3-hydroxybutyrate (3-OHB) than mitochondria from NP, MP, and LP hearts, with no differences in RCR. These increases in respiration in PB hearts occurred independent of changes in mitochondrial yield but were associated with higher abundance of 3-hydroxybutyrate dehydrogenase 1. Collectively, these findings suggest that, after birth, maternal cardiac mitochondria have an increased capacity to use 3-OHB, pyruvate, and glutamate as energy sources; however, increases in mitochondrial efficiency in the postpartum heart appear limited to carbohydrate and amino acid metabolism.NEW & NOTEWORTHY Few studies have detailed the physiological adaptations that occur in the maternal heart. We and others have shown that pregnancy-induced cardiac growth is associated with significant changes in cardiac metabolism. Here, we examined mitochondrial respiration and substrate preference in isolated mitochondria from the maternal heart. We show that following birth, cardiac mitochondria are "primed" to respire on carbohydrate, amino acid, and ketone bodies. However, heightened respiratory efficiency is observed only with carbohydrate and amino acid sources. These results suggest that significant changes in mitochondrial respiration occur in the maternal heart in the postpartum period.
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Affiliation(s)
- Emily B Schulman-Geltzer
- Division of Environmental Medicine, Department of Medicine, Center for Cardiometabolic ScienceChristina Lee Brown Envirome Institute, University of Louisville, Louisville, Kentucky, United States
| | - Kyle L Fulghum
- Division of Environmental Medicine, Department of Medicine, Center for Cardiometabolic ScienceChristina Lee Brown Envirome Institute, University of Louisville, Louisville, Kentucky, United States
| | - Richa A Singhal
- Division of Environmental Medicine, Department of Medicine, Center for Cardiometabolic ScienceChristina Lee Brown Envirome Institute, University of Louisville, Louisville, Kentucky, United States
| | - Bradford G Hill
- Division of Environmental Medicine, Department of Medicine, Center for Cardiometabolic ScienceChristina Lee Brown Envirome Institute, University of Louisville, Louisville, Kentucky, United States
| | - Helen E Collins
- Division of Environmental Medicine, Department of Medicine, Center for Cardiometabolic ScienceChristina Lee Brown Envirome Institute, University of Louisville, Louisville, Kentucky, United States
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Kane MS, Benavides GA, Osuma E, Johnson MS, Collins HE, He Y, Westbrook D, Litovsky SH, Mitra K, Chatham JC, Darley-Usmar V, Young ME, Zhang J. The interplay between sex, time of day, fasting status, and their impact on cardiac mitochondrial structure, function, and dynamics. Sci Rep 2023; 13:21638. [PMID: 38062139 PMCID: PMC10703790 DOI: 10.1038/s41598-023-49018-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 12/03/2023] [Indexed: 12/18/2023] Open
Abstract
Mitochondria morphology and function, and their quality control by mitophagy, are essential for heart function. We investigated whether these are influenced by time of the day (TOD), sex, and fed or fasting status, using transmission electron microscopy (EM), mitochondrial electron transport chain (ETC) activity, and mito-QC reporter mice. We observed peak mitochondrial number at ZT8 in the fed state, which was dependent on the intrinsic cardiac circadian clock, as hearts from cardiomyocyte-specific BMAL1 knockout (CBK) mice exhibit different TOD responses. In contrast to mitochondrial number, mitochondrial ETC activities do not fluctuate across TOD, but decrease immediately and significantly in response to fasting. Concurrent with the loss of ETC activities, ETC proteins were decreased with fasting, simultaneous with significant increases of mitophagy, mitochondrial antioxidant protein SOD2, and the fission protein DRP1. Fasting-induced mitophagy was lost in CBK mice, indicating a direct role of BMAL1 in regulating mitophagy. This is the first of its kind report to demonstrate the interactions between sex, fasting, and TOD on cardiac mitochondrial structure, function and mitophagy. These studies provide a foundation for future investigations of mitochondrial functional perturbation in aging and heart diseases.
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Affiliation(s)
- Mariame S Kane
- Department of Pathology, University of Alabama at Birmingham, 901 19th Street S., Birmingham, AL, BMRII-53435294-0017, USA
- Birmingham VA Health Care System (BVACS), Birmingham, USA
| | - Gloria A Benavides
- Department of Pathology, University of Alabama at Birmingham, 901 19th Street S., Birmingham, AL, BMRII-53435294-0017, USA
| | - Edie Osuma
- Department of Pathology, University of Alabama at Birmingham, 901 19th Street S., Birmingham, AL, BMRII-53435294-0017, USA
- Baylor College of Medicine, Houston, USA
| | - Michelle S Johnson
- Department of Pathology, University of Alabama at Birmingham, 901 19th Street S., Birmingham, AL, BMRII-53435294-0017, USA
| | - Helen E Collins
- Department of Pathology, University of Alabama at Birmingham, 901 19th Street S., Birmingham, AL, BMRII-53435294-0017, USA
- Department of Medicine, University of Louisville, Louisville, USA
| | - Yecheng He
- Department of Pathology, University of Alabama at Birmingham, 901 19th Street S., Birmingham, AL, BMRII-53435294-0017, USA
- Department of Clinical Medicine, Suzhou Vocational Health College, Suzhou, Jiangsu, China
| | - David Westbrook
- Department of Pathology, University of Alabama at Birmingham, 901 19th Street S., Birmingham, AL, BMRII-53435294-0017, USA
| | - Silvio H Litovsky
- Department of Pathology, University of Alabama at Birmingham, 901 19th Street S., Birmingham, AL, BMRII-53435294-0017, USA
| | - Kasturi Mitra
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL, USA
- Ashoka University, Sonipat, NCR (Delhi), India
| | - John C Chatham
- Department of Pathology, University of Alabama at Birmingham, 901 19th Street S., Birmingham, AL, BMRII-53435294-0017, USA
| | - Victor Darley-Usmar
- Department of Pathology, University of Alabama at Birmingham, 901 19th Street S., Birmingham, AL, BMRII-53435294-0017, USA
| | - Martin E Young
- Department of Medicine, University of Alabama at Birmingham, 703 19th St. S., ZRB 308, Birmingham, AL, 35294, USA.
| | - Jianhua Zhang
- Department of Pathology, University of Alabama at Birmingham, 901 19th Street S., Birmingham, AL, BMRII-53435294-0017, USA.
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Schulman-Geltzer EB, Collins HE, Hill BG, Fulghum KL. Coordinated Metabolic Responses Facilitate Cardiac Growth in Pregnancy and Exercise. Curr Heart Fail Rep 2023; 20:441-450. [PMID: 37581772 PMCID: PMC10589193 DOI: 10.1007/s11897-023-00622-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/19/2023] [Indexed: 08/16/2023]
Abstract
PURPOSE OF REVIEW Pregnancy and exercise are systemic stressors that promote physiological growth of the heart in response to repetitive volume overload and maintenance of cardiac output. This type of remodeling is distinct from pathological hypertrophy and involves different metabolic mechanisms that facilitate growth; however, it remains unclear how metabolic changes in the heart facilitate growth and if these processes are similar in both pregnancy- and exercise-induced cardiac growth. RECENT FINDINGS The ability of the heart to metabolize a myriad of substrates balances cardiac demands for energy provision and anabolism. During pregnancy, coordination of hormonal status with cardiac reductions in glucose oxidation appears important for physiological growth. During exercise, a reduction in cardiac glucose oxidation also appears important for physiological growth, which could facilitate shuttling of glucose-derived carbons into biosynthetic pathways for growth. Understanding the metabolic underpinnings of physiological cardiac growth could provide insight to optimize cardiovascular health and prevent deleterious remodeling, such as that which occurs from postpartum cardiomyopathy and heart failure. This short review highlights the metabolic mechanisms known to facilitate pregnancy-induced and exercise-induced cardiac growth, both of which require changes in cardiac glucose metabolism for the promotion of growth. In addition, we mention important similarities and differences of physiological cardiac growth in these models as well as discuss current limitations in our understanding of metabolic changes that facilitate growth.
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Affiliation(s)
- Emily B Schulman-Geltzer
- Center for Cardiometabolic Science, Christina Lee Brown Envirome Institute, Department of Medicine, University of Louisville, Louisville, KY, USA
| | - Helen E Collins
- Center for Cardiometabolic Science, Christina Lee Brown Envirome Institute, Department of Medicine, University of Louisville, Louisville, KY, USA
| | - Bradford G Hill
- Center for Cardiometabolic Science, Christina Lee Brown Envirome Institute, Department of Medicine, University of Louisville, Louisville, KY, USA
| | - Kyle L Fulghum
- Center for Cardiometabolic Science, Christina Lee Brown Envirome Institute, Department of Medicine, University of Louisville, Louisville, KY, USA.
- Division of Molecular Medicine, Department of Medicine, University of Minnesota, Minneapolis, MN, USA.
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Collins HE. Female cardiovascular biology and resilience in the setting of physiological and pathological stress. Redox Biol 2023; 63:102747. [PMID: 37216702 PMCID: PMC10209889 DOI: 10.1016/j.redox.2023.102747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 04/29/2023] [Accepted: 05/12/2023] [Indexed: 05/24/2023] Open
Abstract
For years, females were thought of as smaller men with complex hormonal cycles; as a result, females have been largely excluded from preclinical and clinical research. However, in the last ten years, with the increased focus on sex as a biological variable, it has become clear that this is not the case, and in fact, male and female cardiovascular biology and cardiac stress responses differ substantially. Premenopausal women are protected from cardiovascular diseases, such as myocardial infarction and resultant heart failure, having preserved cardiac function, reduced adverse remodeling, and increased survival. Many underlying biological processes that contribute to ventricular remodeling differ between the sexes, such as cellular metabolism; immune cell responses; cardiac fibrosis and extracellular matrix remodeling; cardiomyocyte dysfunction; and endothelial biology; however, it is unclear how these changes afford protection to the female heart. Although many of these changes are dependent on protection provided by female sex hormones, several of these changes occur independent of sex hormones, suggesting that the nature of these changes is more complex than initially thought. This may be why studies focused on the cardiovascular benefits of hormone replacement therapy in post-menopausal women have provided mixed results. Some of the complexity likely stems from the fact that the cellular composition of the heart is sexually dimorphic and that in the setting of MI, different subpopulations of these cell types are apparent. Despite the documented sex-differences in cardiovascular (patho)physiology, the underlying mechanisms that contribute are largely unknown due to inconsistent findings amongst investigators and, in some cases, lack of rigor in reporting and consideration of sex-dependent variables. Therefore, this review aims to describe current understanding of the sex-dependent differences in the myocardium in response to physiological and pathological stressors, with a focus on the sex-dependent differences that contribute to post-infarction remodeling and resultant functional decline.
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Affiliation(s)
- Helen E Collins
- Center for Cardiometabolic Science, Christina Lee Brown Envirome Institute, Division of Environmental Medicine, Department of Medicine, Delia B. Baxter Research Building, University of Louisville, 580 S. Preston S, Louisville, KY 40202, USA.
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Ouyang X, Bakshi S, Benavides GA, Sun Z, Hernandez-Moreno G, Collins HE, Kane MS, Litovsky S, Young ME, Chatham JC, Darley-Usmar V, Wende AR, Zhang J. Cardiomyocyte ZKSCAN3 regulates remodeling following pressure-overload. Physiol Rep 2023; 11:e15686. [PMID: 37144628 PMCID: PMC10161215 DOI: 10.14814/phy2.15686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Accepted: 02/22/2023] [Indexed: 05/06/2023] Open
Abstract
Autophagy is important for protein and organelle quality control. Growing evidence demonstrates that autophagy is tightly controlled by transcriptional mechanisms, including repression by zinc finger containing KRAB and SCAN domains 3 (ZKSCAN3). We hypothesize that cardiomyocyte-specific ZKSCAN3 knockout (Z3K) disrupts autophagy activation and repression balance and exacerbates cardiac pressure-overload-induced remodeling following transverse aortic constriction (TAC). Indeed, Z3K mice had an enhanced mortality compared to control (Con) mice following TAC. Z3K-TAC mice that survived exhibited a lower body weight compared to Z3K-Sham. Although both Con and Z3K mice exhibited cardiac hypertrophy after TAC, Z3K mice exhibited TAC-induced increase of left ventricular posterior wall thickness at end diastole (LVPWd). Conversely, Con-TAC mice exhibited decreases in PWT%, fractional shortening (FS%), and ejection fraction (EF%). Autophagy genes (Tfeb, Lc3b, and Ctsd) were decreased by the loss of ZKSCAN3. TAC suppressed Zkscan3, Tfeb, Lc3b, and Ctsd in Con mice, but not in Z3K. The Myh6/Myh7 ratio, which is related to cardiac remodeling, was decreased by the loss of ZKSCAN3. Although Ppargc1a mRNA and citrate synthase activities were decreased by TAC in both genotypes, mitochondrial electron transport chain activity did not change. Bi-variant analyses show that while in Con-Sham, the levels of autophagy and cardiac remodeling mRNAs form a strong correlation network, such was disrupted in Con-TAC, Z3K-Sham, and Z3K-TAC. Ppargc1a also forms different links in Con-sham, Con-TAC, Z3K-Sham, and Z3K-TAC. We conclude that ZKSCAN3 in cardiomyocytes reprograms autophagy and cardiac remodeling gene transcription, and their relationships with mitochondrial activities in response to TAC-induced pressure overload.
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Affiliation(s)
- Xiaosen Ouyang
- Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Sayan Bakshi
- Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Gloria A Benavides
- Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Zhihuan Sun
- Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | | | - Helen E Collins
- Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Mariame S Kane
- Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Silvio Litovsky
- Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Martin E Young
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - John C Chatham
- Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Victor Darley-Usmar
- Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Adam R Wende
- Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Jianhua Zhang
- Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA
- Birmingham VA Medical Center, University of Alabama at Birmingham, Birmingham, Alabama, USA
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Schulman EB, Hill BG, Collins HE. Abstract P2019: Do Changes In Metabolism Or Lactation Mediate The Reversal Of Pregnancy-induced Cardiac Growth? Circ Res 2022. [DOI: 10.1161/res.131.suppl_1.p2019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
During pregnancy, the maternal heart undergoes physiologic growth, which reverses following parturition and is associated with the restoration of hemodynamic parameters. However, the molecular processes underlying the reversal of pregnancy-induced cardiac growth and the time frame in which these changes occur remain unclear. Because changes in cardiac metabolism have been shown to influence the remodeling in the maternal heart, changes in metabolism may also contribute to the reversal of pregnancy-induced remodeling. Therefore, the goal of this study was to examine the underlying processes that contribute to the structural and functional changes occurring in the maternal heart following parturition. Timed pregnancy studies in 12-week-old female FVB/NJ mice showed that heart weight to tibia length (HW:TL) and cardiomyocyte size were highest in lactating 1-week post-birth (PB) mice versus mid-pregnant (8 d), late-pregnant (LP; 16 d), and non-pregnant (NP) mice. Interestingly, we also found that HW:TL was significantly reduced in non-lactating 1-week post-birth mice (PBNL) compared with LP mice. To determine the time-course of the reversal of pregnancy-induced remodeling and to examine the impact of lactation, we examined HW:TL in PB and PBNL mice 1, 3, and 6 weeks following parturition. We find that HW:TL is significantly higher in lactating PB mice versus non-lactating PBNL mice at 1 (8.71 ± 0.05 v 7.09 ± 0.26 mg/mm) and 3 weeks following parturition (8.90 ± 0.40 v 6.92 ± 0.56 mg/mm); however, 6 weeks after parturition, HW:TL was comparable between PB (7.35 ± 0.29 mg/mm) and PBNL groups (7.05 ± 0.18 mg/mm). Nevertheless, HW:TL remained elevated for 6 weeks after parturition in PB and PBNL mice compared with NP mice. RNA-Seq showed reductions in metabolic transcripts in PB hearts, including
Pdk4
. Immunoblot analysis of key metabolic proteins showed that Pdk4 was reduced in hearts from 1 and 3 PB versus 1 and 3 weeks PBNL and NP. Together, these findings suggest that lactation influences the reversal of pregnancy-induced cardiac growth, which may be due in part to changes in cardiac metabolism.
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Fulghum K, Collins HE, Jones SP, Hill BG. Influence of biological sex and exercise on murine cardiac metabolism. J Sport Health Sci 2022; 11:479-494. [PMID: 35688382 PMCID: PMC9338340 DOI: 10.1016/j.jshs.2022.06.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 04/07/2022] [Accepted: 04/27/2022] [Indexed: 05/03/2023]
Abstract
Although the structural and functional effects of exercise on the heart are well established, the metabolic changes that occur in the heart during and after exercise remain unclear. In this study, we used metabolomics to assess time-dependent changes in the murine cardiac metabolome following 1 session of treadmill exercise. After the exercise bout, we also recorded blood lactate, glucose, and ketone body levels and measured cardiac mitochondrial respiration. In both male and female mice, moderate- and high-intensity exercise acutely increased blood lactate levels. In both sexes, low- and moderate-intensity exercise augmented circulating 3-hydroxybutryrate levels immediately after the exercise bout; however, only in female mice did high-intensity exercise increase 3-hydroxybutyrate levels, with significant increases occurring 1 h after the exercise session. Untargeted metabolomics analyses of sedentary female and male hearts suggest considerable sex-dependent differences in basal cardiac metabolite levels, with female hearts characterized by higher levels of pantothenate, pyridoxamine, homoarginine, tryptophan, and several glycerophospholipid and sphingomyelin species and lower levels of numerous metabolites, including acetyl coenzyme A, glucuronate, gulonate, hydroxyproline, prolyl-hydroxyproline, carnosine, anserine, and carnitinylated and glycinated species, as compared with male hearts. Immediately after a bout of treadmill exercise, both male and female hearts had higher levels of corticosterone; however, female mice showed more extensive exercise-induced changes in the cardiac metabolome, characterized by significant, time-dependent changes in amino acids (e.g., serine, alanine, tyrosine, tryptophan, branched-chain amino acids) and the ketone body 3-hydroxybutyrate. Results from experiments using isolated cardiac mitochondria suggest that high-intensity treadmill exercise does not acutely affect respiration or mitochondrial coupling; however, female cardiac mitochondria demonstrate generally higher adenosine diphosphate sensitivity compared with male cardiac mitochondria. Collectively, these findings in mice reveal key sex-dependent differences in cardiac metabolism and suggest that the metabolic network in the female heart is more responsive to physiological stress caused by exercise.
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Affiliation(s)
- Kyle Fulghum
- Diabetes and Obesity Center, Department of Medicine, Division of Environmental Medicine, Christina Lee Brown Envirome Institute, University of Louisville, Louisville, KY 40202, USA; Department of Physiology, University of Louisville, Louisville, KY 40202, USA
| | - Helen E Collins
- Diabetes and Obesity Center, Department of Medicine, Division of Environmental Medicine, Christina Lee Brown Envirome Institute, University of Louisville, Louisville, KY 40202, USA
| | - Steven P Jones
- Diabetes and Obesity Center, Department of Medicine, Division of Environmental Medicine, Christina Lee Brown Envirome Institute, University of Louisville, Louisville, KY 40202, USA
| | - Bradford G Hill
- Diabetes and Obesity Center, Department of Medicine, Division of Environmental Medicine, Christina Lee Brown Envirome Institute, University of Louisville, Louisville, KY 40202, USA.
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Fulghum KL, Smith JB, Chariker J, Garrett LF, Brittian KR, Lorkiewicz P, McNally LA, Uchida S, Jones SP, Hill BG, Collins HE. Metabolic Signatures of Pregnancy-Induced Cardiac Growth. Am J Physiol Heart Circ Physiol 2022; 323:H146-H164. [PMID: 35622533 DOI: 10.1152/ajpheart.00105.2022] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The goal of this study was to develop an atlas of the metabolic, transcriptional, and proteomic changes that occur with pregnancy in the maternal heart. Timed pregnancy studies in FVB/NJ mice revealed significant increases in heart size by day 8 of pregnancy (mid-pregnancy; MP), which was sustained throughout the rest of the term compared with non-pregnant controls. Cardiac hypertrophy and myocyte cross-sectional area were highest 7 d after birth (post-birth; PB) and were associated with significant increases in end-diastolic and end-systolic left ventricular volumes and cardiac output. Metabolomics analyses revealed that, by day 16 of pregnancy (late pregnancy; LP), metabolites associated with nitric oxide production as well as acylcholines, sphingomyelins, and fatty acid species were elevated, which coincided with a lower activation state of phosphofructokinase and higher levels of pyruvate dehydrogenase kinase 4 (Pdk4). In the postpartum period, urea cycle metabolites, polyamines, and phospholipid levels were markedly elevated in the maternal heart. Cardiac transcriptomics in LP revealed significant increases in not only Pdk4, but also genes that regulate glutamate and ketone body oxidation, which were preceded in MP by higher expression of transcripts controlling cell proliferation and angiogenesis. Proteomics analysis of the maternal heart in LP and PB revealed significant reductions in several contractile filaments and mitochondrial complex subunits. Collectively, these findings describe the coordinated molecular changes that occur in the maternal heart during and after pregnancy.
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Affiliation(s)
- Kyle L Fulghum
- Diabetes and Obesity Center, Christina Lee Brown Envirome Institute, Division of Environmental Medicine, Department of Medicine, University of Louisville, Louisville, KY, United States
| | - Juliette B Smith
- Diabetes and Obesity Center, Christina Lee Brown Envirome Institute, Division of Environmental Medicine, Department of Medicine, University of Louisville, Louisville, KY, United States
| | - Julia Chariker
- KY INBRE Genomics Core, University of Louisville, Louisville, KY, United States
| | - Lauren F Garrett
- Diabetes and Obesity Center, Christina Lee Brown Envirome Institute, Division of Environmental Medicine, Department of Medicine, University of Louisville, Louisville, KY, United States
| | - Kenneth R Brittian
- Diabetes and Obesity Center, Christina Lee Brown Envirome Institute, Division of Environmental Medicine, Department of Medicine, University of Louisville, Louisville, KY, United States
| | - Pawel Lorkiewicz
- Diabetes and Obesity Center, Christina Lee Brown Envirome Institute, Division of Environmental Medicine, Department of Medicine, University of Louisville, Louisville, KY, United States
| | - Lindsey A McNally
- Diabetes and Obesity Center, Christina Lee Brown Envirome Institute, Division of Environmental Medicine, Department of Medicine, University of Louisville, Louisville, KY, United States
| | - Shizuka Uchida
- Center for RNA Medicine, Department of Clinical Medicine, Aalborg University, Copenhagen, Denmark
| | - Steven P Jones
- Diabetes and Obesity Center, Christina Lee Brown Envirome Institute, Division of Environmental Medicine, Department of Medicine, University of Louisville, Louisville, KY, United States
| | - Bradford G Hill
- Diabetes and Obesity Center, Christina Lee Brown Envirome Institute, Division of Environmental Medicine, Department of Medicine, University of Louisville, Louisville, KY, United States
| | - Helen E Collins
- Diabetes and Obesity Center, Christina Lee Brown Envirome Institute, Division of Environmental Medicine, Department of Medicine, University of Louisville, Louisville, KY, United States
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Collins HE, Zhang D, Chatham JC. STIM and Orai Mediated Regulation of Calcium Signaling in Age-Related Diseases. Front Aging 2022; 3:876785. [PMID: 35821821 PMCID: PMC9261457 DOI: 10.3389/fragi.2022.876785] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 03/30/2022] [Indexed: 01/19/2023]
Abstract
Tight spatiotemporal regulation of intracellular Ca2+ plays a critical role in regulating diverse cellular functions including cell survival, metabolism, and transcription. As a result, eukaryotic cells have developed a wide variety of mechanisms for controlling Ca2+ influx and efflux across the plasma membrane as well as Ca2+ release and uptake from intracellular stores. The STIM and Orai protein families comprising of STIM1, STIM2, Orai1, Orai2, and Orai3, are evolutionarily highly conserved proteins that are core components of all mammalian Ca2+ signaling systems. STIM1 and Orai1 are considered key players in the regulation of Store Operated Calcium Entry (SOCE), where release of Ca2+ from intracellular stores such as the Endoplasmic/Sarcoplasmic reticulum (ER/SR) triggers Ca2+ influx across the plasma membrane. SOCE, which has been widely characterized in non-excitable cells, plays a central role in Ca2+-dependent transcriptional regulation. In addition to their role in Ca2+ signaling, STIM1 and Orai1 have been shown to contribute to the regulation of metabolism and mitochondrial function. STIM and Orai proteins are also subject to redox modifications, which influence their activities. Considering their ubiquitous expression, there has been increasing interest in the roles of STIM and Orai proteins in excitable cells such as neurons and myocytes. While controversy remains as to the importance of SOCE in excitable cells, STIM1 and Orai1 are essential for cellular homeostasis and their disruption is linked to various diseases associated with aging such as cardiovascular disease and neurodegeneration. The recent identification of splice variants for most STIM and Orai isoforms while complicating our understanding of their function, may also provide insight into some of the current contradictions on their roles. Therefore, the goal of this review is to describe our current understanding of the molecular regulation of STIM and Orai proteins and their roles in normal physiology and diseases of aging, with a particular focus on heart disease and neurodegeneration.
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Affiliation(s)
- Helen E. Collins
- Division of Environmental Medicine, Department of Medicine, University of Louisville, Louisville, KY, United States
| | - Dingguo Zhang
- Division of Molecular and Cellular Pathology, Department of PathologyUniversity of Alabama at Birmingham, Birmingham, AL, United States
| | - John C. Chatham
- Division of Molecular and Cellular Pathology, Department of PathologyUniversity of Alabama at Birmingham, Birmingham, AL, United States,*Correspondence: John C. Chatham,
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11
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Collins HE, Anderson JC, Wende AR, Chatham JC. Cardiomyocyte stromal interaction molecule 1 is a key regulator of Ca 2+ -dependent kinase and phosphatase activity in the mouse heart. Physiol Rep 2022; 10:e15177. [PMID: 35179826 PMCID: PMC8855923 DOI: 10.14814/phy2.15177] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 01/04/2022] [Accepted: 01/07/2022] [Indexed: 04/26/2023] Open
Abstract
Stromal interaction molecule 1 (STIM1) is a major regulator of store-operated calcium entry in non-excitable cells. Recent studies have suggested that STIM1 plays a role in pathological hypertrophy; however, the physiological role of STIM1 in the heart is not well understood. We have shown that mice with a cardiomyocyte deletion of STIM1 (cr STIM1-/- ) develop ER stress, mitochondrial, and metabolic abnormalities, and dilated cardiomyopathy. However, the specific signaling pathways and kinases regulated by STIM1 are largely unknown. Therefore, we used a discovery-based kinomics approach to identify kinases differentially regulated by STIM1. Twelve-week male control and cr STIM1-/- mice were injected with saline or phenylephrine (PE, 15 mg/kg, s.c, 15 min), and hearts obtained for analysis of the Serine/threonine kinome. Primary analysis was performed using BioNavigator 6.0 (PamGene), using scoring from the Kinexus PhosphoNET database and GeneGo network modeling, and confirmed using standard immunoblotting. Kinomics revealed significantly lower PKG and protein kinase C (PKC) signaling in the hearts of the cr STIM1-/- in comparison to control hearts, confirmed by immunoblotting for the calcium-dependent PKC isoform PKCα and its downstream target MARCKS. Similar reductions in cr STIM1-/- hearts were found for the kinases: MEK1/2, AMPK, and PDPK1, and in the activity of the Ca2+ -dependent phosphatase, calcineurin. Electrocardiogram analysis also revealed that cr STIM1-/- mice have significantly lower HR and prolonged QT interval. In conclusion, we have shown several calcium-dependent kinases and phosphatases are regulated by STIM1 in the adult mouse heart. This has important implications in understanding how STIM1 contributes to the regulation of cardiac physiology and pathophysiology.
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Affiliation(s)
- Helen E. Collins
- Division of Environmental MedicineDepartment of MedicineUniversity of LouisvilleLouisvilleKentuckyUSA
| | - Joshua C. Anderson
- Department of Radiation OncologyUniversity of Alabama at BirminghamBirminghamAlabamaUSA
| | - Adam R. Wende
- Division of Molecular and Cellular PathologyDepartment of PathologyUniversity of Alabama at BirminghamBirminghamAlabamaUSA
| | - John C. Chatham
- Division of Molecular and Cellular PathologyDepartment of PathologyUniversity of Alabama at BirminghamBirminghamAlabamaUSA
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12
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Bamber D, Collins HE, Powell C, Gonçalves GC, Johnson S, Manktelow B, Ornelas JP, Lopes JC, Rocha A, Draper ES. Development of a data classification system for preterm birth cohort studies: the RECAP Preterm project. BMC Med Res Methodol 2022; 22:8. [PMID: 34996382 PMCID: PMC8742427 DOI: 10.1186/s12874-021-01494-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 12/06/2021] [Indexed: 11/17/2022] Open
Abstract
Background The small sample sizes available within many very preterm (VPT) longitudinal birth cohort studies mean that it is often necessary to combine and harmonise data from individual studies to increase statistical power, especially for studying rare outcomes. Curating and mapping data is a vital first step in the process of data harmonisation. To facilitate data mapping and harmonisation across VPT birth cohort studies, we developed a custom classification system as part of the Research on European Children and Adults born Preterm (RECAP Preterm) project in order to increase the scope and generalisability of research and the evaluation of outcomes across the lifespan for individuals born VPT. Methods The multidisciplinary consortium of expert clinicians and researchers who made up the RECAP Preterm project participated in a four-phase consultation process via email questionnaire to develop a topic-specific classification system. Descriptive analyses were calculated after each questionnaire round to provide pre- and post- ratings to assess levels of agreement with the classification system as it developed. Amendments and refinements were made to the classification system after each round. Results Expert input from 23 clinicians and researchers from the RECAP Preterm project aided development of the classification system’s topic content, refining it from 10 modules, 48 themes and 197 domains to 14 modules, 93 themes and 345 domains. Supplementary classifications for target, source, mode and instrument were also developed to capture additional variable-level information. Over 22,000 individual data variables relating to VPT birth outcomes have been mapped to the classification system to date to facilitate data harmonisation. This will continue to increase as retrospective data items are mapped and harmonised variables are created. Conclusions This bespoke preterm birth classification system is a fundamental component of the RECAP Preterm project’s web-based interactive platform. It is freely available for use worldwide by those interested in research into the long term impact of VPT birth. It can also be used to inform the development of future cohort studies. Supplementary Information The online version contains supplementary material available at 10.1186/s12874-021-01494-5.
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Affiliation(s)
- Deborah Bamber
- Department of Health Sciences, University of Leicester, Leicester, UK
| | - Helen E Collins
- Department of Health Sciences, University of Leicester, Leicester, UK
| | - Charlotte Powell
- Department of Health Sciences, University of Leicester, Leicester, UK
| | - Gonçalo Campos Gonçalves
- INESC TEC - Institute for Systems and Computer Engineering, Technology and Science, Porto, Portugal
| | - Samantha Johnson
- Department of Health Sciences, University of Leicester, Leicester, UK
| | - Bradley Manktelow
- Department of Health Sciences, University of Leicester, Leicester, UK
| | - José Pedro Ornelas
- INESC TEC - Institute for Systems and Computer Engineering, Technology and Science, Porto, Portugal
| | - João Correia Lopes
- INESC TEC - Institute for Systems and Computer Engineering, Technology and Science, Porto, Portugal.,Faculdade de Engenharia da Universidade do Porto, Porto, Portugal
| | - Artur Rocha
- INESC TEC - Institute for Systems and Computer Engineering, Technology and Science, Porto, Portugal
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13
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Zou L, Collins HE, Young ME, Zhang J, Wende AR, Darley-Usmar VM, Chatham JC. The Identification of a Novel Calcium-Dependent Link Between NAD + and Glucose Deprivation-Induced Increases in Protein O-GlcNAcylation and ER Stress. Front Mol Biosci 2021; 8:780865. [PMID: 34950703 PMCID: PMC8691773 DOI: 10.3389/fmolb.2021.780865] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Accepted: 11/22/2021] [Indexed: 01/19/2023] Open
Abstract
The modification of proteins by O-linked β-N-acetylglucosamine (O-GlcNAc) is associated with the regulation of numerous cellular processes. Despite the importance of O-GlcNAc in mediating cellular function our understanding of the mechanisms that regulate O-GlcNAc levels is limited. One factor known to regulate protein O-GlcNAc levels is nutrient availability; however, the fact that nutrient deficient states such as ischemia increase O-GlcNAc levels suggests that other factors also contribute to regulating O-GlcNAc levels. We have previously reported that in unstressed cardiomyocytes exogenous NAD+ resulted in a time and dose dependent decrease in O-GlcNAc levels. Therefore, we postulated that NAD+ and cellular O-GlcNAc levels may be coordinately regulated. Using glucose deprivation as a model system in an immortalized human ventricular cell line, we examined the influence of extracellular NAD+ on cellular O-GlcNAc levels and ER stress in the presence and absence of glucose. We found that NAD+ completely blocked the increase in O-GlcNAc induced by glucose deprivation and suppressed the activation of ER stress. The NAD+ metabolite cyclic ADP-ribose (cADPR) had similar effects on O-GlcNAc and ER stress suggesting a common underlying mechanism. cADPR is a ryanodine receptor (RyR) agonist and like caffeine, which also activates the RyR, both mimicked the effects of NAD+. SERCA inhibition, which also reduces ER/SR Ca2+ levels had similar effects to both NAD+ and cADPR on O-GlcNAc and ER stress responses to glucose deprivation. The observation that NAD+, cADPR, and caffeine all attenuated the increase in O-GlcNAc and ER stress in response to glucose deprivation, suggests a potential common mechanism, linked to ER/SR Ca2+ levels, underlying their activation. Moreover, we showed that TRPM2, a plasma membrane cation channel was necessary for the cellular responses to glucose deprivation. Collectively, these findings support a novel Ca2+-dependent mechanism underlying glucose deprivation induced increase in O-GlcNAc and ER stress.
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Affiliation(s)
- Luyun Zou
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Helen E. Collins
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Martin E. Young
- Division of Cardiovascular Diseases, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Jianhua Zhang
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, United States,Birmingham VA Medical Center, Birmingham, AL, United States
| | - Adam R. Wende
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Victor M. Darley-Usmar
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - John C. Chatham
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, United States,*Correspondence: John C. Chatham,
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14
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Collins HE, Kane MS, Litovsky SH, Darley-Usmar VM, Young ME, Chatham JC, Zhang J. Mitochondrial Morphology and Mitophagy in Heart Diseases: Qualitative and Quantitative Analyses Using Transmission Electron Microscopy. Front Aging 2021; 2:670267. [PMID: 35822027 PMCID: PMC9261312 DOI: 10.3389/fragi.2021.670267] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Accepted: 03/26/2021] [Indexed: 01/21/2023]
Abstract
Transmission electron microscopy (TEM) has long been an important technique, capable of high degree resolution and visualization of subcellular structures and organization. Over the last 20 years, TEM has gained popularity in the cardiovascular field to visualize changes at the nanometer scale in cardiac ultrastructure during cardiovascular development, aging, and a broad range of pathologies. Recently, the cardiovascular TEM enabled the studying of several signaling processes impacting mitochondrial function, such as mitochondrial fission/fusion, autophagy, mitophagy, lysosomal degradation, and lipophagy. The goals of this review are to provide an overview of the current usage of TEM to study cardiac ultrastructural changes; to understand how TEM aided the visualization of mitochondria, autophagy, and mitophagy under normal and cardiovascular disease conditions; and to discuss the overall advantages and disadvantages of TEM and potential future capabilities and advancements in the field.
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Affiliation(s)
- Helen E. Collins
- Division of Environmental Medicine, Department of Medicine, University of Louisville, KY, United States
| | - Mariame Selma Kane
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Silvio H. Litovsky
- Division of Anatomic Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Victor M. Darley-Usmar
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Martin E. Young
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - John C. Chatham
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Jianhua Zhang
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, United States
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15
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Collins HE, Fulghum K, McNally LA, Foster ML, Brittian K, Uchida S, Nystoriak MA, Jones SP, Hill BG. Abstract 526: Unraveling the Molecular Signature of Pregnancy Induced Hypertrophy. Circ Res 2020. [DOI: 10.1161/res.127.suppl_1.526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Cardiovascular disease is the leading cause of death in pregnant and postpartum women. During pregnancy, the maternal heart rapidly adapts to the increasing physiological and metabolic demands of the growing fetus. This adaptation often takes the form of a physiological hypertrophy in which the maternal heart grows to increase cardiac output; however, the molecular processes underlying pregnancy-induced hypertrophy (PIH) are poorly understood. The goal of this study was to examine the transcriptomic and metabolic signatures associated with the structural and functional adaptations of the heart to pregnancy. Therefore, we performed timed pregnancy studies in 12-week-old female FVB/NJ mice, which were distributed into the following groups: non-pregnant control (NP;
n
= 14), mid-pregnancy (MP, 6d pregnant;
n
= 11), late-pregnancy (LP, 16d pregnant;
n
= 13), and 1-wk post birth (PB;
n
= 8). Heart weight to tibia length were higher in MP (7.77±1.02 mg/mm;
p
<0.05), LP (7.84±0.87 mg/mm;
p
<0.05), and PB mice (9.86±1.14 mg/mm;
p
<0.05) compared with NP mice (6.54±0.74 mg/mm). The sustained increase in PB heart weight was associated with increased myocyte cross sectional area, consistent with cardiomyocyte hypertrophy. Compared with NP hearts, echocardiographic measurements suggest significant increases in both end diastolic (36.0±5.1 vs 61.2±5.9 μl;
p
<0.05) and systolic LV volume (9.4±3.8 vs 21.0±1.4 μl;
p
<0.05) in PB hearts. These changes in PB hearts were associated with a significant increase in LV mass and a decline in ejection fraction. In LP and PB hearts, we also found higher expression of markers of hypertrophy (
Nppa, Nppb, Myh7
). Subsequent RNA-seq analyses revealed enrichment in genes involved in cell proliferation, cytokinesis, and transcription in MP hearts; in metabolism genes in LP hearts; and in fibrotic and extracellular matrix genes in PB hearts. Together, these findings reveal the key molecular signature underlying the structural and functional adaptation of the heart during pregnancy and parturition, and may shed light on the molecular processes underlying PIH.
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16
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Collins HE, Chatham JC. Regulation of cardiac O-GlcNAcylation: More than just nutrient availability. Biochim Biophys Acta Mol Basis Dis 2020; 1866:165712. [PMID: 32014551 DOI: 10.1016/j.bbadis.2020.165712] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 01/15/2020] [Accepted: 01/27/2020] [Indexed: 12/12/2022]
Abstract
The post-translational modification of serine and threonine residues of nuclear, cytosolic, and mitochondrial proteins by O-linked β-N-acetyl glucosamine (O-GlcNAc) has long been seen as an important regulatory mechanism in the cardiovascular system. O-GlcNAcylation of cardiac proteins has been shown to contribute to the regulation of transcription, metabolism, mitochondrial function, protein quality control and turnover, autophagy, and calcium handling. In the heart, acute increases in O-GlcNAc have been associated with cardioprotection, such as those observed during ischemia/reperfusion. Conversely, chronic increases in O-GlcNAc, often associated with diabetes and nutrient excess, have been shown to contribute to cardiac dysfunction. Traditionally, many studies have linked changes in O-GlcNAc with nutrient availability and as such O-GlcNAcylation is often seen as a nutrient driven process. However, emerging evidence suggests that O-GlcNAcylation may also be regulated by non-nutrient dependent mechanisms, such as transcriptional and post-translational regulation. Therefore, the goals of this review are to provide an overview of the impact of O-GlcNAcylation in the cardiovascular system, how this is regulated and to discuss the emergence of regulatory mechanisms other than nutrient availability.
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Affiliation(s)
- Helen E Collins
- Division of Environmental Medicine, Department of Medicine, University of Louisville, Louisville, KY, United States of America
| | - John C Chatham
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, United States of America.
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17
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Wright JN, Benavides GA, Johnson MS, Wani W, Ouyang X, Zou L, Collins HE, Zhang J, Darley-Usmar V, Chatham JC. Acute increases in O-GlcNAc indirectly impair mitochondrial bioenergetics through dysregulation of LonP1-mediated mitochondrial protein complex turnover. Am J Physiol Cell Physiol 2019; 316:C862-C875. [PMID: 30865517 PMCID: PMC6620580 DOI: 10.1152/ajpcell.00491.2018] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 02/19/2019] [Accepted: 03/09/2019] [Indexed: 12/26/2022]
Abstract
The attachment of O-linked β-N-acetylglucosamine (O-GlcNAc) to the serine and threonine residues of proteins in distinct cellular compartments is increasingly recognized as an important mechanism regulating cellular function. Importantly, the O-GlcNAc modification of mitochondrial proteins has been identified as a potential mechanism to modulate metabolism under stress with both potentially beneficial and detrimental effects. This suggests that temporal and dose-dependent changes in O-GlcNAcylation may have different effects on mitochondrial function. In the current study, we found that acutely augmenting O-GlcNAc levels by inhibiting O-GlcNAcase with Thiamet-G for up to 6 h resulted in a time-dependent decrease in cellular bioenergetics and decreased mitochondrial complex I, II, and IV activities. Under these conditions, mitochondrial number was unchanged, whereas an increase in the protein levels of the subunits of several electron transport complex proteins was observed. However, the observed bioenergetic changes appeared not to be due to direct increased O-GlcNAc modification of complex subunit proteins. Increases in O-GlcNAc were also associated with an accumulation of mitochondrial ubiquitinated proteins; phosphatase and tensin homolog induced kinase 1 (PINK1) and p62 protein levels were also significantly increased. Interestingly, the increase in O-GlcNAc levels was associated with a decrease in the protein levels of the mitochondrial Lon protease homolog 1 (LonP1), which is known to target complex IV subunits and PINK1, in addition to other mitochondrial proteins. These data suggest that impaired bioenergetics associated with short-term increases in O-GlcNAc levels could be due to impaired, LonP1-dependent, mitochondrial complex protein turnover.
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Affiliation(s)
- JaLessa N Wright
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama , Birmingham, Alabama
| | - Gloria A Benavides
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama , Birmingham, Alabama
| | - Michelle S Johnson
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama , Birmingham, Alabama
| | - Willayat Wani
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama , Birmingham, Alabama
| | - Xiaosen Ouyang
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama , Birmingham, Alabama
| | - Luyun Zou
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama , Birmingham, Alabama
| | - Helen E Collins
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama , Birmingham, Alabama
| | - Jianhua Zhang
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama , Birmingham, Alabama
- Birmingham VA Medical Center, University of Alabama , Birmingham, Alabama
| | - Victor Darley-Usmar
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama , Birmingham, Alabama
| | - John C Chatham
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama , Birmingham, Alabama
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Collins HE, Pat BM, Zou L, Litovsky SH, Wende AR, Young ME, Chatham JC. Novel role of the ER/SR Ca 2+ sensor STIM1 in the regulation of cardiac metabolism. Am J Physiol Heart Circ Physiol 2018; 316:H1014-H1026. [PMID: 30575437 PMCID: PMC6580390 DOI: 10.1152/ajpheart.00544.2018] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The endoplasmic reticulum/sarcoplasmic reticulum Ca2+ sensor stromal interaction molecule 1 (STIM1), a key mediator of store-operated Ca2+ entry, is expressed in cardiomyocytes and has been implicated in regulating multiple cardiac processes, including hypertrophic signaling. Interestingly, cardiomyocyte-restricted deletion of STIM1 (crSTIM1-KO) results in age-dependent endoplasmic reticulum stress, altered mitochondrial morphology, and dilated cardiomyopathy in mice. Here, we tested the hypothesis that STIM1 deficiency may also impact cardiac metabolism. Hearts isolated from 20-wk-old crSTIM1-KO mice exhibited a significant reduction in both oxidative and nonoxidative glucose utilization. Consistent with the reduction in glucose utilization, expression of glucose transporter 4 and AMP-activated protein kinase phosphorylation were all reduced, whereas pyruvate dehydrogenase kinase 4 and pyruvate dehydrogenase phosphorylation were increased, in crSTIM1-KO hearts. Despite similar rates of fatty acid oxidation in control and crSTIM1-KO hearts ex vivo, crSTIM1-KO hearts contained increased lipid/triglyceride content as well as increased fatty acid-binding protein 4, fatty acid synthase, acyl-CoA thioesterase 1, hormone-sensitive lipase, and adipose triglyceride lipase expression compared with control hearts, suggestive of a possible imbalance between fatty acid uptake and oxidation. Insulin-mediated alterations in AKT phosphorylation were observed in crSTIM1-KO hearts, consistent with cardiac insulin resistance. Interestingly, we observed abnormal mitochondria and increased lipid accumulation in 12-wk crSTIM1-KO hearts, suggesting that these changes may initiate the subsequent metabolic dysfunction. These results demonstrate, for the first time, that cardiomyocyte STIM1 may play a key role in regulating cardiac metabolism. NEW & NOTEWORTHY Little is known of the physiological role of stromal interaction molecule 1 (STIM1) in the heart. Here, we demonstrate, for the first time, that hearts lacking cardiomyocyte STIM1 exhibit dysregulation of both cardiac glucose and lipid metabolism. Consequently, these results suggest a potentially novel role for STIM1 in regulating cardiac metabolism.
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Affiliation(s)
- Helen E Collins
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham , Birmingham, Alabama
| | - Betty M Pat
- Division of Cardiovascular Medicine, Department of Medicine, University of Alabama at Birmingham , Birmingham, Alabama
| | - Luyun Zou
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham , Birmingham, Alabama
| | - Silvio H Litovsky
- Division of Anatomic Pathology, Department of Pathology, University of Alabama at Birmingham , Birmingham, Alabama
| | - Adam R Wende
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham , Birmingham, Alabama
| | - Martin E Young
- Division of Cardiovascular Medicine, Department of Medicine, University of Alabama at Birmingham , Birmingham, Alabama
| | - John C Chatham
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham , Birmingham, Alabama
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19
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Brewer RA, Collins HE, Berry RD, Brahma MK, Tirado BA, Peliciari-Garcia RA, Stanley HL, Wende AR, Taegtmeyer H, Rajasekaran NS, Darley-Usmar V, Zhang J, Frank SJ, Chatham JC, Young ME. Temporal partitioning of adaptive responses of the murine heart to fasting. Life Sci 2018; 197:30-39. [PMID: 29410090 DOI: 10.1016/j.lfs.2018.01.031] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 01/29/2018] [Accepted: 01/30/2018] [Indexed: 12/16/2022]
Abstract
Recent studies suggest that the time of day at which food is consumed dramatically influences clinically-relevant cardiometabolic parameters (e.g., adiposity, insulin sensitivity, and cardiac function). Meal feeding benefits may be the result of daily periods of feeding and/or fasting, highlighting the need for improved understanding of the temporal adaptation of cardiometabolic tissues (e.g., heart) to fasting. Such studies may provide mechanistic insight regarding how time-of-day-dependent feeding/fasting cycles influence cardiac function. We hypothesized that fasting during the sleep period elicits beneficial adaptation of the heart at transcriptional, translational, and metabolic levels. To test this hypothesis, temporal adaptation was investigated in wild-type mice fasted for 24-h, or for either the 12-h light/sleep phase or the 12-h dark/awake phase. Fasting maximally induced fatty acid responsive genes (e.g., Pdk4) during the dark/active phase; transcriptional changes were mirrored at translational (e.g., PDK4) and metabolic flux (e.g., glucose/oleate oxidation) levels. Similarly, maximal repression of myocardial p-mTOR and protein synthesis rates occurred during the dark phase; both parameters remained elevated in the heart of fasted mice during the light phase. In contrast, markers of autophagy (e.g., LC3II) exhibited peak responses to fasting during the light phase. Collectively, these data show that responsiveness of the heart to fasting is temporally partitioned. Autophagy peaks during the light/sleep phase, while repression of glucose utilization and protein synthesis is maximized during the dark/active phase. We speculate that sleep phase fasting may benefit cardiac function through augmentation of protein/cellular constituent turnover.
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Affiliation(s)
- Rachel A Brewer
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Helen E Collins
- Division of Molecular Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Ryan D Berry
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Manoja K Brahma
- Division of Molecular Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Brian A Tirado
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Rodrigo A Peliciari-Garcia
- Morphophysiology & Pathology Sector, Department of Biological Sciences, Federal University of São Paulo, Diadema, SP, Brazil
| | - Haley L Stanley
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Adam R Wende
- Division of Molecular Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Heinrich Taegtmeyer
- Division of Cardiology, Department of Internal Medicine, McGovern Medical School UT Health Science Center, Houston, TX, USA
| | - Namakkal Soorappan Rajasekaran
- Division of Molecular Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Victor Darley-Usmar
- Division of Molecular Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jianhua Zhang
- Division of Molecular Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Stuart J Frank
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA; Endocrinology Section, Birmingham VAMC Medical Service, Birmingham, AL, USA
| | - John C Chatham
- Division of Molecular Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Martin E Young
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA.
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Collins HE, Chatham JC. Non-voltage-gated Ca²⁺ entry pathways in the heart: the untold STOrai? Cardiovasc Res 2015; 105:233-4. [PMID: 25280892 DOI: 10.1093/cvr/cvu217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Helen E Collins
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - John C Chatham
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
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Abstract
Our understanding of the role of protein O-GlcNAcylation in the regulation of the cardiovascular system has increased rapidly in recent years. Studies have linked increased O-GlcNAc levels to glucose toxicity and diabetic complications; conversely, acute activation of O-GlcNAcylation has been shown to be cardioprotective. However, it is also increasingly evident that O-GlcNAc turnover plays a central role in the delicate regulation of the cardiovascular system. Therefore, the goals of this minireview are to summarize our current understanding of how changes in O-GlcNAcylation influence cardiovascular pathophysiology and to highlight the evidence that O-GlcNAc cycling is critical for normal function of the cardiovascular system.
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Affiliation(s)
- Susan A Marsh
- From the Section of Experimental and Systems Pharmacology, College of Pharmacy, Washington State University, Spokane, Washington 99210-1495 and
| | - Helen E Collins
- the Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama 35294-0019
| | - John C Chatham
- the Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama 35294-0019
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Young ME, Brewer RA, Peliciari-Garcia RA, Collins HE, He L, Birky TL, Peden BW, Thompson EG, Ammons BJ, Bray MS, Chatham JC, Wende AR, Yang Q, Chow CW, Martino TA, Gamble KL. Cardiomyocyte-specific BMAL1 plays critical roles in metabolism, signaling, and maintenance of contractile function of the heart. J Biol Rhythms 2014; 29:257-76. [PMID: 25238855 PMCID: PMC4260630 DOI: 10.1177/0748730414543141] [Citation(s) in RCA: 145] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Circadian clocks are cell autonomous, transcriptionally based, molecular mechanisms that confer the selective advantage of anticipation, enabling cells/organs to respond to environmental factors in a temporally appropriate manner. Critical to circadian clock function are 2 transcription factors, CLOCK and BMAL1. The purpose of the present study was to reveal novel physiologic functions of BMAL1 in the heart, as well as to determine the pathologic consequences of chronic disruption of this circadian clock component. To address this goal, we generated cardiomyocyte-specific Bmal1 knockout (CBK) mice. Following validation of the CBK model, combined microarray and in silico analyses were performed, identifying 19 putative direct BMAL1 target genes, which included a number of metabolic (e.g., β-hydroxybutyrate dehydrogenase 1 [Bdh1]) and signaling (e.g., the p85α regulatory subunit of phosphatidylinositol 3-kinase [Pik3r1]) genes. Results from subsequent validation studies were consistent with regulation of Bdh1 and Pik3r1 by BMAL1, with predicted impairments in ketone body metabolism and signaling observed in CBK hearts. Furthermore, CBK hearts exhibited depressed glucose utilization, as well as a differential response to a physiologic metabolic stress (i.e., fasting). Consistent with BMAL1 influencing critical functions in the heart, echocardiographic, gravimetric, histologic, and molecular analyses revealed age-onset development of dilated cardiomyopathy in CBK mice, which was associated with a severe reduction in life span. Collectively, our studies reveal that BMAL1 influences metabolism, signaling, and contractile function of the heart.
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Affiliation(s)
- Martin E Young
- Division of Cardiovascular Diseases, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Rachel A Brewer
- Division of Cardiovascular Diseases, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Rodrigo A Peliciari-Garcia
- Division of Cardiovascular Diseases, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA Institute of Biomedical Sciences-I, Department of Physiology and Biophysics, University of Sao Paulo, Sao Paulo, Brazil
| | - Helen E Collins
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Lan He
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Tana L Birky
- Division of Cardiovascular Diseases, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Bradley W Peden
- Division of Cardiovascular Diseases, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Emily G Thompson
- Division of Cardiovascular Diseases, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Billy-Joe Ammons
- Division of Cardiovascular Diseases, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Molly S Bray
- Department of Epidemiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - John C Chatham
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Adam R Wende
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Qinglin Yang
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Chi-Wing Chow
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Tami A Martino
- Department of Biomedical Science, University of Guelph, Guelph, Ontario, Canada
| | - Karen L Gamble
- Division of Behavioral Neurobiology, Department of Psychiatry, University of Alabama at Birmingham, Birmingham, Alabama, USA
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23
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Collins HE, He L, Zou L, Qu J, Zhou L, Litovsky SH, Yang Q, Young ME, Marchase RB, Chatham JC. Stromal interaction molecule 1 is essential for normal cardiac homeostasis through modulation of ER and mitochondrial function. Am J Physiol Heart Circ Physiol 2014; 306:H1231-9. [PMID: 24585777 DOI: 10.1152/ajpheart.00075.2014] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The endoplasmic reticulum (ER) Ca(2+) sensor stromal interaction molecule 1 (STIM1) has been implicated as a key mediator of store-dependent and store-independent Ca(2+) entry pathways and maintenance of ER structure. STIM1 is present in embryonic, neonatal, and adult cardiomyocytes and has been strongly implicated in hypertrophic signaling; however, the physiological role of STIM1 in the adult heart remains unknown. We, therefore, developed a novel cardiomyocyte-restricted STIM1 knockout ((cr)STIM1-KO) mouse. In cardiomyocytes isolated from (cr)STIM1-KO mice, STIM1 expression was reduced by ∼92% with no change in the expression of related store-operated Ca(2+) entry proteins, STIM2, and Orai1. Immunoblot analyses revealed that (cr)STIM1-KO hearts exhibited increased ER stress from 12 wk, as indicated by increased levels of the transcription factor C/EBP homologous protein (CHOP), one of the terminal markers of ER stress. Transmission electron microscopy revealed ER dilatation, mitochondrial disorganization, and increased numbers of smaller mitochondria in (cr)STIM1-KO hearts, which was associated with increased mitochondrial fission. Using serial echocardiography and histological analyses, we observed a progressive decline in cardiac function in (cr)STIM1-KO mice, starting at 20 wk of age, which was associated with marked left ventricular dilatation by 36 wk. In addition, we observed the presence of an inflammatory infiltrate and evidence of cardiac fibrosis from 20 wk in (cr)STIM1-KO mice, which progressively worsened by 36 wk. These data demonstrate for the first time that STIM1 plays an essential role in normal cardiac function in the adult heart, which may be important for the regulation of ER and mitochondrial function.
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Affiliation(s)
- Helen E Collins
- Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama
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Abstract
Store-operated Ca²⁺ entry (SOCE) is critical for Ca²⁺ signaling in nonexcitable cells; however, its role in the regulation of cardiomyocyte Ca²⁺ homeostasis has only recently been investigated. The increased understanding of the role of stromal interaction molecule 1 (STIM1) in regulating SOCE combined with recent studies demonstrating the presence of STIM1 in cardiomyocytes provides support that this pathway co-exists in the heart with the more widely recognized Ca²⁺ handling pathways associated with excitation-contraction coupling. There is now substantial evidence that STIM1-mediated SOCE plays a key role in mediating cardiomyocyte hypertrophy, both in vitro and in vivo, and there is growing support for the contribution of SOCE to Ca²⁺ overload associated with ischemia/reperfusion injury. Here, we provide an overview of our current understanding of the molecular regulation of SOCE and discuss the evidence supporting the role of STIM1/Orai1-mediated SOCE in regulating cardiomyocyte function.
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Affiliation(s)
- Helen E Collins
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama
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25
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Wang C, Houghton MJ, Gamage PPKM, Collins HE, Patel BA, Yeoman MS, Ranson RN, Saffrey MJ. Changes in the innervation of the mouse internal anal sphincter during aging. Neurogastroenterol Motil 2013; 25:e469-77. [PMID: 23634828 DOI: 10.1111/nmo.12144] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 03/28/2013] [Indexed: 12/20/2022]
Abstract
BACKGROUND The innervation of the mouse internal anal sphincter (IAS) has been little studied, and how it changes during aging has not previously been investigated. The aim of this study was therefore to characterize the distribution and density of subtypes of nerve fibers in the IAS and underlying mucosa in 3-, 12- to 13-, 18- and 24- to 25-month-old male C57BL/6 mice. METHODS Nerve fibers were immunolabeled with antibodies against protein gene product 9.5 (PGP9.5), neuronal nitric oxide synthase (nNOS), vasoactive intestinal polypeptide (VIP), substance P (SP), calcitonin gene-related peptide (CGRP), and calretinin (CR). Immunoreactivity in nerve fibers in the circular muscle and mucosa was quantified using Image J software. KEY RESULTS In young adult (3 month) mice, nNOS-immunoreactive (IR) nerve fibers were densely distributed in the circular muscle, but relatively few in the mucosa; VIP-IR nerve fibers were abundant in the circular muscle and common in the mucosa; SP-IR nerve fibers were common in circular muscle and mucosa; CGRP- and CR-IR nerve fibers were dense in mucosa and sparse in circular muscle. The density of PGP9.5 immunoreactivity (IRY) was not significantly reduced with age, but a significant reduction in nNOS-IRY and SP-IRY with age was found in the IAS circular muscle. Neuronal nitric oxide synthase-, VIP-, and SP-IRY in the anal mucosa were significantly reduced with age. CGRP-IRY in both circular muscle and mucosa was increased in 18-month-old animals. CONCLUSIONS & INFERENCES The density of immunoreactivity of markers for some types of IAS nerve fibers decreases during aging, which may contribute to age-related ano-rectal dysfunction.
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Affiliation(s)
- C Wang
- Department of Life, Health and Chemical Sciences, The Open University, Milton Keynes, UK
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26
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Collins HE, Rodrigo GC. Inotropic response of cardiac ventricular myocytes to beta-adrenergic stimulation with isoproterenol exhibits diurnal variation: involvement of nitric oxide. Circ Res 2010; 106:1244-52. [PMID: 20167926 DOI: 10.1161/circresaha.109.213942] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
RATIONALE Although >10% of cardiac gene expression displays diurnal variations, little is known of their impact on excitation-contraction coupling. OBJECTIVE To determine whether the time of day affects excitation-contraction coupling in rat ventricles. METHODS AND RESULTS Left ventricular myocytes were isolated from rat hearts at 2 opposing time points, corresponding to the animals resting or active periods. Basal contraction and [Ca(2+)](i) was significantly greater in myocytes isolated during the resting versus active periods (cell shortening 12.4+/-0.3 versus 11.0+/-0.2%; P<0.05 and systolic [Ca(2+)](i) 422+/-12 versus 341+/-9 nmol/L; P<0.01. This corresponded to a greater sarcoplasmic reticulum (SR) Ca(2+) load (672+/-20 versus 551+/-13 nmol/L P<0.001). The increase in systolic [Ca(2+)](i) in response to isoproterenol (>3 nmol/L) was also significantly greater in resting versus active period myocytes, reflecting a greater SR Ca(2+) load at this time. This diurnal variation in response of Ca(2+)-homeostasis to isoproterenol translated to a greater incidence of arrhythmic activity in resting period myocytes. Inhibition of neuronal NO synthase during stimulation with isoproterenol, further increased systolic [Ca(2+)](i) and the percentage of arrhythmic myocytes, but this effect was significantly greater in active period versus resting period myocytes. Quantitative RT-PCR analysis revealed a 2.65-fold increase in neuronal NO synthase mRNA levels in active over resting period myocytes (P<0.05). CONCLUSIONS The threshold for the development of arrhythmic activity in response to isoproterenol is higher during the active period of the rat. We suggest this reflects a reduction in SR Ca(2+) loading and a diurnal variation in neuronal NO synthase signaling.
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MESH Headings
- Adrenergic beta-Agonists/adverse effects
- Adrenergic beta-Agonists/pharmacology
- Animals
- Arrhythmias, Cardiac/chemically induced
- Arrhythmias, Cardiac/metabolism
- Calcium/metabolism
- Calcium Channels, L-Type/drug effects
- Calcium Channels, L-Type/metabolism
- Calcium Signaling/drug effects
- Cardiac Pacing, Artificial
- Circadian Rhythm
- Dose-Response Relationship, Drug
- Excitation Contraction Coupling/drug effects
- Gene Expression Regulation, Enzymologic/drug effects
- Heart Ventricles/drug effects
- Heart Ventricles/metabolism
- Homeostasis
- Isoproterenol/adverse effects
- Isoproterenol/pharmacology
- Male
- Myocardial Contraction/drug effects
- Myocytes, Cardiac/drug effects
- Myocytes, Cardiac/metabolism
- Nitric Oxide/metabolism
- Nitric Oxide Synthase/genetics
- Nitric Oxide Synthase/metabolism
- Nitric Oxide Synthase Type I
- RNA, Messenger/metabolism
- Rats
- Rats, Wistar
- Sarcoplasmic Reticulum/drug effects
- Sarcoplasmic Reticulum/metabolism
- Up-Regulation
- Ventricular Function, Left/drug effects
- Ventricular Pressure/drug effects
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Affiliation(s)
- Helen E Collins
- Department of Cardiovascular Sciences, University of Leicester, Glenfield General Hospital, Leicester LE3 9QP, United Kingdom
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27
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Collins HE, Li H, Inda SE, Anderson J, Laiho K, Tuomilehto J, Seldin MF. A simple and accurate method for determination of microsatellite total allele content differences between DNA pools. Hum Genet 2000; 106:218-26. [PMID: 10746564 DOI: 10.1007/s004390051031] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
DNA pooling is a potential tool for the efficient analysis of the large numbers of samples and DNA markers that are necessary for genome-wide association studies. A simple accurate method for measuring total allele differences in comparisons between two pools containing large numbers of DNA samples is presented. This method compares relative peak height differences between electrophoretograms for each allele of a microsatellite. The method was evaluated by the analysis of 11 microsatellite markers and DNA pooled sample sizes of 50, 100, and 200 individual DNA samples from the same number of different subjects. Pools were created from previously individually genotyped subjects and constructed so that the pool comparisons would provide real total allele differences varying from 0% to 55%. Calculated pool differences were then compared with the real total allele differences determined by individual genotyping results. Together over 200 comparisons demonstrated a correlation coefficient of 0.96, which compared favorably with other previous methods of analysis. This method could provide a rapid screen for total allele differences of greater than 10%, a threshold that should be applicable to detecting low relative risk genes in common diseases. Therefore, these studies suggest that DNA pooling could be a useful tool in association studies for the determination of candidate regions for a range of complex genetic diseases.
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Affiliation(s)
- H E Collins
- Department of Biological Chemistry and Medicine, University of California, Davis 95616-8669, USA
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28
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Kashani-Sabet M, Sagebiel RW, Collins HE, Glassberg AB, Allen RE, Leong SP, Small EJ. Outpatient combination chemoimmunotherapy for patients with metastatic melanoma. Results of a phase I/II trial. Cancer 1999; 86:2160-5. [PMID: 10570447 DOI: 10.1002/(sici)1097-0142(19991115)86:10<2160::aid-cncr40>3.0.co;2-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND Few studies have examined the feasibility, safety, and efficacy of an outpatient biochemotherapy regimen of low dose, subcutaneously administered interleukin-2 (IL-2) for patients with metastatic (Stage IV) melanoma. METHODS Nineteen patients were treated with intravenous cisplatin and dacarbazine (DTIC), oral tamoxifen, and subcutaneous IL-2 and interferon-alpha-2b (IFN). Eligibility requirements included bidimensionally measurable metastatic melanoma, a Karnofsky performance score of 60 or higher, absence of significant cardiac or pulmonary dysfunction, no prior DTIC or cisplatin chemotherapy, and no evidence of central nervous system involvement. Patients were given a minimum of 2 6-week cycles. Treatment was continued in the absence of progressive disease, and patients were monitored for response at two-cycle intervals. RESULTS Of the 19 patients, 1 (5%) achieved a complete response; 6 (32%) a partial response; 3 (16%) stable disease; and 9 (47%) progressive disease, for an overall response proportion of 37% (95% confidence interval, 16-61%). The median survival of the treated cohort was 10.6 months. The mean time to disease progression for patients with stable disease or better was 8.4 months, with a mean response duration of 5.1 months. The most common toxicities noted were constitutional symptoms, weight loss, nausea, neutropenia, and fatigue. The 19 patients received a total of 59 cycles of treatment, and IL-2, IFN, or both were held in 14 of these cycles secondary to Grade 3 or 4 toxicities. In addition, six patients required dose reduction of IL-2 and/or IFN. CONCLUSIONS Chemoimmunotherapy consisting of cisplatin, DTIC, and tamoxifen combined with subcutaneous IL-2 and IFN can be safely administered in an outpatient setting. The described regimen yields moderate activity in metastatic melanoma, and efforts to improve its efficacy merit further examination.
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Affiliation(s)
- M Kashani-Sabet
- Melanoma Center, University of California San Francisco Clinical Cancer Center, San Francisco, California, USA
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29
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Abstract
Despite the ever-growing body of literature reporting the effects of flavonoids on animals at both the cellular and systemic levels, one of the most basic questions-"Are the effects of flavonoids on animal cells initiated through their interaction with extracellular targets or intracellular targets?"-has yet to be addressed. Because many effects of flavonoids on cells can be detected within minutes of flavonoid application and because flavonoids diffuse across lipid membranes slowly or not at all, intracellular mechanisms would necessitate a flavonoid transport system for rapid flavonoid uptake. The specific aims of this investigation were (1) to determine if endothelial cells contain a mechanism that mediates rapid flavonoid uptake and (2) to provide evidence for or against the hypothesis that rapid flavonoid effects on endothelial cell synthesis of prostacyclin and endothelin are initiated through the interaction of flavonoids with intracellular targets. Data show that bovine and human aortic endothelial cells possess a transport system that mediates rapid uptake of the flavonoid morin and suggest that the flavonoid uptake system utilizes a variety of oxygenated phenolic compounds as substrates. Further investigation into flavonoid transport should expedite future investigation into the mechanisms of flavonoid actions, because it may allow research to focus on the cellular locations where flavonoids are concentrated. Although endothelial cells contain a mechanism for the rapid uptake of morin, data reported herein suggest that morin initiates its rapid effects on endothelial cell synthesis of prostacyclin and endothelin through an interaction with extracellular targets.
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Affiliation(s)
- D D Schramm
- Department of Food Science and Technology, Section of Molecular and Cellular Biology, University of California, Davis, CA 95616, USA
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30
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Abstract
Flavonoid plant pigments are an integral part of the human diet. Although potentially negative mitotic effects of flavonoids have been observed in model organisms, investigation into meiotic effects of flavonoids has been neglected. As flavonoids affect cell signalling and DNA replication, and because the flavonoid content of the human food supply is being increased, determining the effects of flavonoids on meiotic fidelity is important. Here, the effect of the human food supply's most prevalent flavonoid, quercetin, on the level of meiotic recombination and the amount of X and 4th chromosome non-disjunction in Drosophila melanogaster females was determined. This model organism was chosen since Drosophila melanogaster and Homo sapiens share a remarkable number of commonalities in the meiotic processes of oogenesis and because genetic techniques allow a detailed analysis of meiotic processes in Drosophila. No significant effect on either non-disjunction levels or the percentage distribution of exchange bivalents was observed. A significant effect was observed on the number of offspring; F1 and F2 generations of flies raised on a quercetin diet produced over 10% more progeny than flies raised on a control diet. In this investigation, high quercetin consumption by Drosophila melanogaster females did not pose a threat to meiotic fidelity.
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Affiliation(s)
- D D Schramm
- Department of Food Science and Technology, University of California at Davis, 95616, USA
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31
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Koehler KE, Boulton CL, Collins HE, French RL, Herman KC, Lacefield SM, Madden LD, Schuetz CD, Hawley RS. Spontaneous X chromosome MI and MII nondisjunction events in Drosophila melanogaster oocytes have different recombinational histories. Nat Genet 1996; 14:406-14. [PMID: 8944020 DOI: 10.1038/ng1296-406] [Citation(s) in RCA: 103] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Recent studies of human oocytes have demonstrated an enrichment for distal exchanges among meiosis I (MI) nondisjunction events and for proximal exchanges among meiosis II (MII) events. Our characterization of 103 cases of spontaneous X chromosome nondisjunction in Drosophila oocytes strongly parallels these observations. The recombinational histories of MI (97/103) and MII (6/103) nondisjunctional ova were strikingly different. MI nondisjunction occurred primarily in oocytes with non-exchange X chromosomes; of the new nondisjoining exchange bivalents, most carried distal crossovers. Thus, spontaneous MI nondisjunction reflects the failure of the achiasmate segregation systems. MII nondisjunction occurred only in oocytes with proximal exchanges. We propose several models to explain how very proximal exchanges might impair proper segregation.
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Affiliation(s)
- K E Koehler
- Department of Genetics, University of California at Davis 95616, USA
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