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Gębczyński AK, Sadowska J, Konarzewski M. Differences in the range of thermoneutral zone between mouse strains: potential effects on translational research. Am J Physiol Regul Integr Comp Physiol 2024; 326:R91-R99. [PMID: 38009211 DOI: 10.1152/ajpregu.00154.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 10/27/2023] [Accepted: 11/20/2023] [Indexed: 11/28/2023]
Abstract
Laboratory mice are commonly used for studies emulating human metabolism. To render human energetics, their ratio of daily (DEE) to basal (BMR) energy expenditure of 1.7-1.8 should be maintained. However, the DEE/BMR ratio strongly depends on whether a given study using a mouse model is carried out above, or below the lower critical temperature (LCT) of the thermoneutral zone, which is rarely considered in translational research. Here, we used mice artificially selected for high or low rates of BMR along with literature data to analyze the effect of ambient temperature on possible systematic bias in DEE/BMR. We demonstrated that the estimated LCTs of mice from the high and low BMR lines differ by more than 7°C. Furthermore, the range of variation of LCTs of mouse strains used in translational research spans from 23 to 33°C. Differences between LCTs in our selected mice and other mouse strains are mirrored by differences in their DEE-to-BMR ratio, on average increasing it at the rate of 0.172°C-1 at temperatures below LCT. Given the wide range of LCTs in different mouse strains, we conclude that the energetic cost of thermoregulation may differ greatly for different mouse strains with a potentially large impact on translational outcomes. Thus, the LCT of a given mouse strain is an important factor that must be considered in designing translational studies.
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Affiliation(s)
| | - Julita Sadowska
- Faculty of Biology, University of Białystok, Białystok, Poland
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2
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Wong CP, Iwaniec UT, Turner RT. Brown adipose tissue but not tibia exhibits a dramatic response to acute reduction in environmental temperature in growing male mice. Bone Rep 2023; 19:101706. [PMID: 37637756 PMCID: PMC10448410 DOI: 10.1016/j.bonr.2023.101706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Revised: 08/04/2023] [Accepted: 08/07/2023] [Indexed: 08/29/2023] Open
Abstract
Mice are typically housed at room temperature (∼22 °C), which is well below their thermoneutral zone and results in cold stress. Chronic cold stress leads to increased adaptive thermogenesis and reductions in cancellous bone volume and bone marrow adipose tissue mass in long bones of growing mice. There is strong evidence that increased neuronal activity initiates the metabolic response of intrascapular brown adipose tissue (BAT) to cold stress, but it is less clear whether bone is regulated through a similar mechanism. Therefore, we compared the short-term response of BAT and whole tibia to a reduction in environmental temperature. To accomplish this, we transferred a group of 6-week-old male mice from 32 °C to 22 °C housing and sacrificed the mice 24 h later. Age-matched controls were maintained at 32 °C. We then evaluated expression levels of a panel of genes related to adipocyte differentiation and fat metabolism in BAT and tibia, and a panel of genes related to bone metabolism in tibia. The decrease in housing temperature resulted in changes in expression levels for 47/86 genes related to adipocyte differentiation and fat metabolism in BAT, including 9-fold and 17-fold increases in Ucp1 and Dio2, respectively. In contrast, only 1/86 genes related to adipocyte differentiation and fat metabolism and 4/84 genes related to bone metabolism were differentially expressed in tibia. These findings suggest that bone, although innervated with sensory and sympathetic neurons, does not respond as rapidly as BAT to changes in environmental temperature.
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Affiliation(s)
- Carmen P. Wong
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, OR 97331, USA
| | - Urszula T. Iwaniec
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, OR 97331, USA
- Center for Healthy Aging Research, Oregon State University, Corvallis, OR 97331, USA
| | - Russell T. Turner
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, OR 97331, USA
- Center for Healthy Aging Research, Oregon State University, Corvallis, OR 97331, USA
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3
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Desai M, Torsoni AS, Torsoni MA, Eisaghalian A, Ferrini M, Ross MG. Thermoneutrality effects on developmental programming of obesity. J Dev Orig Health Dis 2023; 14:223-230. [PMID: 36097652 PMCID: PMC9998331 DOI: 10.1017/s2040174422000502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Developmental programming studies using mouse models have housed the animals at human thermoneutral temperatures (22°C) which imposes constant cold stress. As this impacts energy homeostasis, we investigated the effects of two housing temperatures (22°C and 30°C) on obesity development in male and female offspring of Control and FR dams. Pregnant mice were housed at 22°C (cold-exposed, CE) or 30°C (thermoneutrality, TN) room temperature. At gestational age e10, mice were fed either an ad libitum diet (Control) or were 30% food-restricted (FR) to produce low birth weight newborns. Following delivery, all dams were fed an ad libitum diet and maternal mice continued to nurse their own pups. At 3 weeks of age, offspring were weaned to an ad libitum diet and housed at similar temperatures as their mothers. Body weights and food intake were monitored. At 6 months of age, body composition and glucose tolerance test were determined, after which, brain and adipose tissue were collected for analysis. FR/CE and FR/TN offspring exhibited hyperphagia and were significantly heavier with increased adiposity as compared to their respective Controls. There was sex-specific effects of temperature in both groups. Male offspring at TN were heavier with increased body fat, though the food intake was decreased as compared to CE males. This was reflected by hypertrophic adipocytes and increased arcuate nucleus satiety/appetite ratio. In contrast, female offspring were not impacted by housing temperature. Thus, unlike female offspring, there was a significant interaction of diet and temperature evident in the male offspring with accentuated adverse effects evident in FR/TN males.
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Affiliation(s)
- Mina Desai
- Perinatal Research Laboratory, The Lundquist Institute at Harbor-UCLA Medical Center, Department of Obstetrics and Gynecology, Torrance, CA
- Department of Obstetrics and Gynecology, David Geffen School of Medicine, University of California, Los Angeles, CA
| | - Adrianna S. Torsoni
- Laboratory of Metabolic Disorders (Labdime), Faculty of Applied Sciences (FCA) of the University of Campinas (UNICAMP), Limeira/SP, Brazil
| | - Marcio A Torsoni
- Laboratory of Metabolic Disorders (Labdime), Faculty of Applied Sciences (FCA) of the University of Campinas (UNICAMP), Limeira/SP, Brazil
| | | | - Monica Ferrini
- Charles R. Drew University of Medicine and Science, Los Angeles, CA
| | - Michael G. Ross
- Perinatal Research Laboratory, The Lundquist Institute at Harbor-UCLA Medical Center, Department of Obstetrics and Gynecology, Torrance, CA
- Department of Obstetrics and Gynecology, David Geffen School of Medicine, University of California, Los Angeles, CA
- Department of Obstetrics and Gynecology, Charles R. Drew University, Los Angeles, CA
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Unger CA, Hope MC, Aladhami AK, Velázquez KT, Enos RT. How stable is your vivarium's temperature? Fluctuations in vivarium temperature significantly impact metabolism and behavior impeding scientific reproducibility. Physiol Behav 2023; 258:114029. [PMID: 36372225 PMCID: PMC10797230 DOI: 10.1016/j.physbeh.2022.114029] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 11/07/2022] [Accepted: 11/08/2022] [Indexed: 11/12/2022]
Abstract
OBJECTIVES The purpose of this investigation was to examine the variability in vivarium temperature and the impact that this has on metabolic and behavioral outcomes in mice. METHODS Daily vivarium temperature was monitored every day for a two-year period. Behavioral and metabolic phenotyping were assessed in male and female C57BL/6 (n = 71/sex) mice over the course of 2 years. RESULTS Vivarium temperature was found to fluctuate on a monthly, daily, and even an hourly basis of approximately ±5ºC. A 5ºC change in temperature was found to result in daily changes in total energy expenditure (35% and 27%), resting energy expenditure (39% for both sexes), movement (51% and 37%), food consumption (35% and 29%), and sleep duration (15% and 13%) for female and male mice, respectively. CONCLUSIONS Fluctuations in vivarium temperature can dramatically impact metabolic and behavioral outcomes, which impedes scientific reproducibility. This awareness and the guidelines we propose in this publication will hopefully help to enhance the reproducibility of pre-clinical animal research.
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Affiliation(s)
- Christian A Unger
- Department of Pathology, Microbiology, and Immunology, University of South Carolina-School of Medicine, Columbia, SC, United States
| | - Marion C Hope
- Department of Pathology, Microbiology, and Immunology, University of South Carolina-School of Medicine, Columbia, SC, United States
| | - Ahmed K Aladhami
- Department of Pathology, Microbiology, and Immunology, University of South Carolina-School of Medicine, Columbia, SC, United States; University of Baghdad, Nursing College, Baghdad, Iraq
| | - Kandy T Velázquez
- Department of Pathology, Microbiology, and Immunology, University of South Carolina-School of Medicine, Columbia, SC, United States
| | - Reilly T Enos
- Department of Pathology, Microbiology, and Immunology, University of South Carolina-School of Medicine, Columbia, SC, United States.
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Turner RT, Nesser KL, Philbrick KA, Wong CP, Olson DA, Branscum AJ, Iwaniec UT. Leptin and environmental temperature as determinants of bone marrow adiposity in female mice. Front Endocrinol (Lausanne) 2022; 13:959743. [PMID: 36277726 PMCID: PMC9582271 DOI: 10.3389/fendo.2022.959743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 09/15/2022] [Indexed: 11/21/2022] Open
Abstract
Bone marrow adipose tissue (BMAT) levels are higher in distal femur metaphysis of female mice housed at thermoneutral (32°C) than in mice housed at 22°C, as are abdominal white adipose tissue (WAT) mass, and serum leptin levels. We performed two experiments to explore the role of increased leptin in temperature-enhanced accrual of BMAT. First, we supplemented 6-week-old female C57BL/6J (B6) mice with leptin for 2 weeks at 10 µg/d using a subcutaneously implanted osmotic pump. Controls consisted of ad libitum (ad lib) fed mice and mice pair fed to match food intake of leptin-supplemented mice. The mice were maintained at 32°C for the duration of treatment. At necropsy, serum leptin in leptin-supplemented mice did not differ from ad lib mice, suggesting suppression of endogenous leptin production. In support, Ucp1 expression in BAT, percent body fat, and abdominal WAT mass were lower in leptin-supplemented mice. Leptin-supplemented mice also had lower BMAT and higher bone formation in distal femur metaphysis compared to the ad lib group, changes not replicated by pair-feeding. In the second experiment, BMAT response was evaluated in 6-week-old female B6 wild type (WT), leptin-deficient ob/ob and leptin-treated (0.3 μg/d) ob/ob mice housed at 32°C for the 2-week duration of the treatment. Compared to mice sacrificed at baseline (22°C), BMAT increased in ob/ob mice as well as WT mice, indicating a leptin independent response to increased temperature. However, infusion of ob/ob mice with leptin, at a dose rate having negligible effects on either energy metabolism or serum leptin levels, attenuated the increase in BMAT. In summary, increased housing temperature and increased leptin have independent but opposing effects on BMAT in mice.
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Affiliation(s)
- Russell T. Turner
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, OR, United States
- Center for Healthy Aging Research, Oregon State University, Corvallis, OR, United States
| | - Kira L. Nesser
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, OR, United States
| | - Kenneth A. Philbrick
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, OR, United States
| | - Carmen P. Wong
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, OR, United States
| | - Dawn A. Olson
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, OR, United States
| | - Adam J. Branscum
- Biostatistics Program, School of Biological and Population Health Sciences, Oregon State University, Corvallis, OR, United States
| | - Urszula T. Iwaniec
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, OR, United States
- Center for Healthy Aging Research, Oregon State University, Corvallis, OR, United States
- *Correspondence: Urszula T. Iwaniec,
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Yu X, Yan H, Li W. Recent advances in neuropeptide-related omics and gene editing: Spotlight on NPY and somatostatin and their roles in growth and food intake of fish. Front Endocrinol (Lausanne) 2022; 13:1023842. [PMID: 36267563 PMCID: PMC9576932 DOI: 10.3389/fendo.2022.1023842] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
Feeding and growth are two closely related and important physiological processes in living organisms. Studies in mammals have provided us with a series of characterizations of neuropeptides and their receptors as well as their roles in appetite control and growth. The central nervous system, especially the hypothalamus, plays an important role in the regulation of appetite. Based on their role in the regulation of feeding, neuropeptides can be classified as orexigenic peptide and anorexigenic peptide. To date, the regulation mechanism of neuropeptide on feeding and growth has been explored mainly from mammalian models, however, as a lower and diverse vertebrate, little is known in fish regarding the knowledge of regulatory roles of neuropeptides and their receptors. In recent years, the development of omics and gene editing technology has accelerated the speed and depth of research on neuropeptides and their receptors. These powerful techniques and tools allow a more precise and comprehensive perspective to explore the functional mechanisms of neuropeptides. This paper reviews the recent advance of omics and gene editing technologies in neuropeptides and receptors and their progresses in the regulation of feeding and growth of fish. The purpose of this review is to contribute to a comparative understanding of the functional mechanisms of neuropeptides in non-mammalians, especially fish.
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Alzamendi A, Miguel I, Zubiría MG, Gambaro SE, Spinedi E, Giovambattista A. Maternal high fructose diet exacerbates white adipose tissue thermogenic process in offspring upon exposure to cold temperature. Life Sci 2021; 287:120066. [PMID: 34678264 DOI: 10.1016/j.lfs.2021.120066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 10/09/2021] [Accepted: 10/15/2021] [Indexed: 12/17/2022]
Abstract
AIM An adverse endogenous environment during early life predisposes to metabolic disorder development. We previously reported adverse metabolic and adipose tissue effects in adult male rats born to dams fed with a fructose-rich diet (FRD). The aim of this work was to determine the effect of a FRD consumed by the pregnant mother on the white adipose tissue (WAT) browning capacity of male offspring at adulthood. MAIN METHODS Adult SD male offspring from control (C) and FRD-fed mothers were exposed during one week to a cold stimulus. WAT browning capacity was studied through in vivo and in vitro approaches. KEY FINDINGS After cold exposure, WAT browning was higher in fructose-programmed animals as evidenced by an increase in ucp-1 gene expression, protein levels, and higher UCP-1 positive foci. Moreover, pgc1-α gene expression was increased. In vitro studies showed a lower adipogenic capacity in cells of prenatally fructose-exposed animals differentiated with a white differentiation cocktail, while a higher ucp-1 expression was noted when their cells were treated with a pro-beige differentiation cocktail. SIGNIFICANCE For the first time we demonstrate that pre-natal fructose exposure predisposes programmed male rats to a higher WAT browning-induced response, under stimulated conditions, despite an apparent lower basal thermogenic capacity. These results should be considered in future studies to generate new therapeutic approaches to deal with adverse programming malnutrition effects.
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Affiliation(s)
- A Alzamendi
- Laboratorio de Neuroendocrinología, Instituto Multidisciplinario de Biología Celular (IMBICE, CICPBA-CONICET-UNLP), Calle 526, 10 y 11, La Plata 1900, Argentina
| | - I Miguel
- Laboratorio de Neuroendocrinología, Instituto Multidisciplinario de Biología Celular (IMBICE, CICPBA-CONICET-UNLP), Calle 526, 10 y 11, La Plata 1900, Argentina
| | - M G Zubiría
- Laboratorio de Neuroendocrinología, Instituto Multidisciplinario de Biología Celular (IMBICE, CICPBA-CONICET-UNLP), Calle 526, 10 y 11, La Plata 1900, Argentina
| | - S E Gambaro
- Laboratorio de Neuroendocrinología, Instituto Multidisciplinario de Biología Celular (IMBICE, CICPBA-CONICET-UNLP), Calle 526, 10 y 11, La Plata 1900, Argentina
| | - E Spinedi
- Centro de Endocrinología Experimental y Aplicada (CENEXA, UNLP-CONICET), Facultad de Cs. Médicas, Universidad Nacional de La Plata, Avenida 60 y 120, La Plata 1900, Argentina
| | - A Giovambattista
- Laboratorio de Neuroendocrinología, Instituto Multidisciplinario de Biología Celular (IMBICE, CICPBA-CONICET-UNLP), Calle 526, 10 y 11, La Plata 1900, Argentina.
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Morrisson MJ, Bi F, Yang K, Cady SL, Hartwich TMP, Cerchia AP, Li Z, Kim J, Irwin ML, Yang-Hartwich Y. Effect of exercise on peritoneal microenvironment and progression of ovarian cancer. Am J Cancer Res 2021; 11:5045-5062. [PMID: 34765311 PMCID: PMC8569339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 06/12/2021] [Indexed: 06/13/2023] Open
Abstract
Ovarian cancer is one of the deadliest gynecological malignancies and lacks treatments that do not significantly impact patient health-related quality of life. Exercise has been associated with reduced cancer risk and improved clinical outcomes; however the underlying molecular mechanisms are unknown. In this study, we utilized a treadmill-running exercise model to investigate the effects of exercise on high-grade serous ovarian carcinoma (HGSOC) progression and chemotherapy outcomes. We found that treadmill-running suppressed peritoneal colonization of tumors in a syngeneic mouse ovarian cancer model. Acute exercise stimulated the production of CCL2 and IL-15 in the peritoneal microenvironment while downregulating CCL22, VEGF, and CCL12. Using a co-culture model, we demonstrated the role of CCL2 in mediating the activity of peritoneal cells to inhibit cancer cell viability. We showed that the activation of M1 macrophages may contribute to the exercise-induced changes in the peritoneal microenvironment. We identified that chronic exercise modulates gene expression of intraperitoneal fat tissues related to lipid formation, thermogenesis, browning, and inflammation, which can contribute to inhibiting the colonization of metastatic ovarian cancer. Treadmill running also lowered blood urea nitrogen levels and reduced incidence of neutropenia and thrombocytopenia during chemotherapy in a mouse model, suggesting the potential beneficial effects of exercise in improving chemotherapy outcomes. Our data provided new insights into the acute and chronic effects of physical activity on ovarian cancer at the molecular and in vivo levels.
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Affiliation(s)
- Madeline J Morrisson
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale School of MedicineNew Haven, CT 06510, USA
| | - Fangfang Bi
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale School of MedicineNew Haven, CT 06510, USA
- Sheng Jing Hospital of China Medical UniversityShenyang 110004, Liaoning, China
| | - Kevin Yang
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale School of MedicineNew Haven, CT 06510, USA
| | - Sarah L Cady
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale School of MedicineNew Haven, CT 06510, USA
| | - Tobias MP Hartwich
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale School of MedicineNew Haven, CT 06510, USA
| | - Alexandra P Cerchia
- Department of Biology and Environmental Science, University of New HavenWest Haven, CT 06516, USA
| | - Zhigui Li
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale School of MedicineNew Haven, CT 06510, USA
| | - Jaeyeon Kim
- Department of Biochemistry and Molecular Biology, Indiana University School of MedicineIndianapolis, IN 46202, USA
- Melvin & Bren Simon Cancer Center, Indiana University School of MedicineIndianapolis, IN 46202, USA
| | - Melinda L Irwin
- Yale School of Public HealthNew Haven, CT 06510, USA
- Yale Cancer CenterNew Haven, CT 06510, USA
| | - Yang Yang-Hartwich
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale School of MedicineNew Haven, CT 06510, USA
- Yale Cancer CenterNew Haven, CT 06510, USA
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Folie S, Radlinger B, Goebel G, Salzmann K, Staudacher G, Ress C, Tilg H, Kaser S. Changing the dietary composition improves inflammation but not adipocyte thermogenesis in diet-induced obese mice. J Nutr Biochem 2021; 99:108837. [PMID: 34419570 DOI: 10.1016/j.jnutbio.2021.108837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 07/11/2021] [Accepted: 07/14/2021] [Indexed: 10/20/2022]
Abstract
Pronounced weight loss was shown to improve adipocyte dysfunction and insulin sensitivity in obese subjects. While bariatric surgery is frequently accompanied by adverse side effects, weight loss due to caloric restriction is often followed by weight regain. Here we aimed to determine whether switching the diet from a metabolically harmful Western type diet to a balanced standard diet is sufficient to reverse adipocyte dysfunction in diet-induced obese mice. Male C57BL/6 mice were fed a Western diet for 10 weeks and afterwards switched to a standard diet for eight more weeks (WD/SD mice) or continued to be fed a Western diet (WD/WD mice) ad libitum. Mice fed SD for 18 weeks served as control group (SD/SD). Insulin sensitivity was similar in WD/SD and SD/SD mice despite increased body weight in WD/SD mice. Beiging markers Ucp-1, Cidea and Cox8b were drastically reduced in subcutaneous adipose tissue of WD/SD mice when compared with SD/SD mice. Also, in brown adipose tissue morphologic features and markers of thermogenesis were still altered in both WD/SD and WD/WD mice. However, adipocyte size, Hif1α and macrophage infiltration were significantly lower in both, brown and white adipose tissues of WD/SD compared to WD/WD mice and additionally, a shift toward anti-inflammatory M2 phenotype was found in WD/SD mice only. In conclusion our data suggest that switching the diet is sufficient to improve adipose tissue inflammation, while western diet negatively affects thermogenic capacity of brown adipose tissue, and inhibits beiging of white adipose tissue in the long-term.
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Affiliation(s)
- Sabrina Folie
- Department of Internal Medicine I, Medical University Innsbruck, Innsbruck, Austria; Christian Doppler Laboratory for Metabolic Crosstalk, Medical University Innsbruck, Innsbruck, Austria
| | - Bernhard Radlinger
- Department of Internal Medicine I, Medical University Innsbruck, Innsbruck, Austria; Christian Doppler Laboratory for Metabolic Crosstalk, Medical University Innsbruck, Innsbruck, Austria
| | - Georg Goebel
- Department of Medical Statistics, Informatics and Health Economics, Medical University Innsbruck, Innsbruck, Austria
| | - Karin Salzmann
- Department of Internal Medicine I, Medical University Innsbruck, Innsbruck, Austria; Christian Doppler Laboratory for Metabolic Crosstalk, Medical University Innsbruck, Innsbruck, Austria
| | - Gabriele Staudacher
- Department of Internal Medicine I, Medical University Innsbruck, Innsbruck, Austria; Christian Doppler Laboratory for Metabolic Crosstalk, Medical University Innsbruck, Innsbruck, Austria
| | - Claudia Ress
- Department of Internal Medicine I, Medical University Innsbruck, Innsbruck, Austria; Christian Doppler Laboratory for Metabolic Crosstalk, Medical University Innsbruck, Innsbruck, Austria
| | - Herbert Tilg
- Department of Internal Medicine I, Medical University Innsbruck, Innsbruck, Austria
| | - Susanne Kaser
- Department of Internal Medicine I, Medical University Innsbruck, Innsbruck, Austria; Christian Doppler Laboratory for Metabolic Crosstalk, Medical University Innsbruck, Innsbruck, Austria.
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Volke L, Krause K. Effect of Thyroid Hormones on Adipose Tissue Flexibility. Eur Thyroid J 2021; 10:1-9. [PMID: 33777816 PMCID: PMC7983599 DOI: 10.1159/000508483] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 05/05/2020] [Indexed: 12/18/2022] Open
Abstract
The recruitment and activation of energy-consuming brown adipocytes is currently considered as potential therapeutic approach to combat obesity. Thyroid hormones (TH) significantly contribute to full thermogenic capacity of brown adipocytes. A number of recent studies suggest that TH also induce the recruitment of brown adipocytes in white adipose depots, a process known as browning. In this review, we will summarize underlying mechanisms by which TH mediate brown adipose tissue activity and white adipose tissue browning. Furthermore, we will discuss the relevance of TH-induced white adipose tissue browning for thermoregulation.
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Affiliation(s)
- Lisa Volke
- Medical Department III-Endocrinology, Nephrology, and Rheumatology, University of Leipzig Medical Center, Leipzig, Germany
- Department of Medicine, University of Leipzig, Leipzig, Germany
| | - Kerstin Krause
- Medical Department III-Endocrinology, Nephrology, and Rheumatology, University of Leipzig Medical Center, Leipzig, Germany
- Department of Medicine, University of Leipzig, Leipzig, Germany
- *Kerstin Krause, Department of Medicine, University of Leipzig, Liebigstrasse 21, DE–04103 Leipzig (Germany),
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11
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AlZaim I, Hammoud SH, Al-Koussa H, Ghazi A, Eid AH, El-Yazbi AF. Adipose Tissue Immunomodulation: A Novel Therapeutic Approach in Cardiovascular and Metabolic Diseases. Front Cardiovasc Med 2020; 7:602088. [PMID: 33282920 PMCID: PMC7705180 DOI: 10.3389/fcvm.2020.602088] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 10/22/2020] [Indexed: 12/12/2022] Open
Abstract
Adipose tissue is a critical regulator of systemic metabolism and bodily homeostasis as it secretes a myriad of adipokines, including inflammatory and anti-inflammatory cytokines. As the main storage pool of lipids, subcutaneous and visceral adipose tissues undergo marked hypertrophy and hyperplasia in response to nutritional excess leading to hypoxia, adipokine dysregulation, and subsequent low-grade inflammation that is characterized by increased infiltration and activation of innate and adaptive immune cells. The specific localization, physiology, susceptibility to inflammation and the heterogeneity of the inflammatory cell population of each adipose depot are unique and thus dictate the possible complications of adipose tissue chronic inflammation. Several lines of evidence link visceral and particularly perivascular, pericardial, and perirenal adipose tissue inflammation to the development of metabolic syndrome, insulin resistance, type 2 diabetes and cardiovascular diseases. In addition to the implication of the immune system in the regulation of adipose tissue function, adipose tissue immune components are pivotal in detrimental or otherwise favorable adipose tissue remodeling and thermogenesis. Adipose tissue resident and infiltrating immune cells undergo metabolic and morphological adaptation based on the systemic energy status and thus a better comprehension of the metabolic regulation of immune cells in adipose tissues is pivotal to address complications of chronic adipose tissue inflammation. In this review, we discuss the role of adipose innate and adaptive immune cells across various physiological and pathophysiological states that pertain to the development or progression of cardiovascular diseases associated with metabolic disorders. Understanding such mechanisms allows for the exploitation of the adipose tissue-immune system crosstalk, exploring how the adipose immune system might be targeted as a strategy to treat cardiovascular derangements associated with metabolic dysfunctions.
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Affiliation(s)
- Ibrahim AlZaim
- Department of Pharmacology and Toxicology, American University of Beirut, Beirut, Lebanon
- Department of Biochemistry and Molecular Genetics, American University of Beirut, Beirut, Lebanon
| | - Safaa H Hammoud
- Department of Pharmacology and Therapeutics, Beirut Arab University, Beirut, Lebanon
| | - Houssam Al-Koussa
- Department of Pharmacology and Toxicology, American University of Beirut, Beirut, Lebanon
| | - Alaa Ghazi
- Department of Pharmacology and Toxicology, American University of Beirut, Beirut, Lebanon
| | - Ali H Eid
- Department of Pharmacology and Therapeutics, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
- Department of Basic Medical Sciences, College of Medicine, Qatar University, Doha, Qatar
- Biomedical and Pharmaceutical Research Unit, QU Health, Qatar University, Doha, Qatar
| | - Ahmed F El-Yazbi
- Department of Pharmacology and Toxicology, American University of Beirut, Beirut, Lebanon
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
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12
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Yuan Z, Xiang R, Li W, Li F, Yue X. Transcriptomic analyses revealed common tailed and perirenal adipose differentially expressed genes in four Chinese indigenous sheep breeds. Livest Sci 2019. [DOI: 10.1016/j.livsci.2019.103832] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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13
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Martin SA, Philbrick KA, Wong CP, Olson DA, Branscum AJ, Jump DB, Marik CK, DenHerder JM, Sargent JL, Turner RT, Iwaniec UT. Thermoneutral housing attenuates premature cancellous bone loss in male C57BL/6J mice. Endocr Connect 2019; 8:1455-1467. [PMID: 31590144 PMCID: PMC6865368 DOI: 10.1530/ec-19-0359] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 10/07/2019] [Indexed: 12/12/2022]
Abstract
Mice are a commonly used model to investigate aging-related bone loss but, in contrast to humans, mice exhibit cancellous bone loss prior to skeletal maturity. The mechanisms mediating premature bone loss are not well established. However, our previous work in female mice suggests housing temperature is a critical factor. Premature cancellous bone loss was prevented in female C57BL/6J mice by housing the animals at thermoneutral temperature (where basal rate of energy production is at equilibrium with heat loss). In the present study, we determined if the protective effects of thermoneutral housing extend to males. Male C57BL/6J mice were housed at standard room temperature (22°C) or thermoneutral (32°C) conditions from 5 (rapidly growing) to 16 (slowly growing) weeks of age. Mice housed at room temperature exhibited reductions in cancellous bone volume fraction in distal femur metaphysis and fifth lumbar vertebra; these effects were abolished at thermoneutral conditions. Mice housed at thermoneutral temperature had higher levels of bone formation in distal femur (based on histomorphometry) and globally (serum osteocalcin), and lower global levels of bone resorption (serum C-terminal telopeptide of type I collagen) compared to mice housed at room temperature. Thermoneutral housing had no impact on bone marrow adiposity but resulted in higher abdominal white adipose tissue and serum leptin. The overall magnitude of room temperature housing-induced cancellous bone loss did not differ between male (current study) and female (published data) mice. These findings highlight housing temperature as a critical experimental variable in studies using mice of either sex to investigate aging-related changes in bone metabolism.
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Affiliation(s)
- Stephen A Martin
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USA
| | - Kenneth A Philbrick
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USA
| | - Carmen P Wong
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USA
| | - Dawn A Olson
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USA
| | - Adam J Branscum
- Biostatistics Program, School of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USA
| | - Donald B Jump
- Molecular Nutrition and Diabetes Research Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USA
| | - Charles K Marik
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USA
| | - Jonathan M DenHerder
- Carlson College of Veterinary Medicine, Oregon State University, Corvallis, Oregon, USA
| | - Jennifer L Sargent
- Carlson College of Veterinary Medicine, Oregon State University, Corvallis, Oregon, USA
| | - Russell T Turner
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USA
- Center for Healthy Aging Research, Oregon State University, Corvallis, Oregon, USA
| | - Urszula T Iwaniec
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USA
- Center for Healthy Aging Research, Oregon State University, Corvallis, Oregon, USA
- Correspondence should be addressed to U T Iwaniec:
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14
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White Adipose Tissue Response of Obese Mice to Ambient Oxygen Restriction at Thermoneutrality: Response Markers Identified, but no WAT Inflammation. Genes (Basel) 2019; 10:genes10050359. [PMID: 31083422 PMCID: PMC6562665 DOI: 10.3390/genes10050359] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 05/03/2019] [Accepted: 05/06/2019] [Indexed: 11/16/2022] Open
Abstract
Obesity is associated with white adipose tissue (WAT) hypoxia and inflammation. We aimed to test whether mild environmental oxygen restriction (OxR, 13% O2), imposing tissue hypoxia, triggers WAT inflammation in obese mice. Thirteen weeks diet-induced obese male adult C57BL/6JOlaHsd mice housed at thermoneutrality were exposed for five days to OxR versus normoxia. WAT and blood were isolated and used for analysis of metabolites and adipokines, WAT histology and macrophage staining, and WAT transcriptomics. OxR increased circulating levels of haemoglobin and haematocrit as well as hypoxia responsive transcripts in WAT and decreased blood glucose, indicating systemic and tissue hypoxia. WAT aconitase activity was inhibited. Macrophage infiltration as marker for WAT inflammation tended to be decreased, which was supported by down regulation of inflammatory genes S100a8, Ccl8, Clec9a, Saa3, Mgst2, and Saa1. Other down regulated processes include cytoskeleton remodelling and metabolism, while response to hypoxia appeared most prominently up regulated. The adipokines coiled-coil domain containing 3 (CCDC3) and adiponectin, as well as the putative WAT hormone cholecystokinin (CCK), were reduced by OxR on transcript (Cck, Ccdc3) and/or serum protein level (adiponectin, CCDC3). Conclusively, our data demonstrate that also in obese mice OxR does not trigger WAT inflammation. However, OxR does evoke a metabolic response in WAT, with CCDC3 and adiponectin as potential markers for systemic or WAT hypoxia.
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15
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Schneider MK, Xue B, Shi H. Activation of the sympathetic nervous system suppresses mouse white adipose tissue hyperplasia through the β1 adrenergic receptor. Physiol Rep 2019; 6:e13645. [PMID: 29611347 PMCID: PMC5880815 DOI: 10.14814/phy2.13645] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 02/11/2018] [Accepted: 02/12/2018] [Indexed: 12/13/2022] Open
Abstract
Adipose tissue (AT) expands via both hypertrophy and hyperplasia during the development of obesity. While AT hypertrophy involves the increase in size of existing adipocytes, hyperplasia is the process of creating new adipocytes from the pool of adipocyte precursor cells (APCs), which includes adipocyte progenitor cells and preadipocytes. Prior studies have implicated a role of the sympathetic nervous system (SNS) in regulation of hyperplasia in white adipose tissue (WAT). Here, we aimed to determine the mechanisms underlying SNS regulation of APC proliferation in mouse WAT. Using flow cytometry with antibodies against various cell surface markers, along with an intracellular marker of proliferation (Ki67), we quantitated the percentages and proliferative status of adipocyte progenitor cells and preadipocytes in the stromal vascular fraction (SVF) of WAT. In vivo SNS activation through cold exposure, as well as in vitro adrenergic stimulation via exposure to the canonical SNS neurotransmitter norepinephrine (NE), inhibited preadipocyte proliferation. Pretreatment with propranolol, a β1‐ and β2‐adrenergic receptor (AR) antagonist, trended toward rescuing the inhibitory effects of NE in primary cell culture. The selective β1‐AR agonist dobutamine diminished preadipocyte proliferation both in vivo and in vitro, whereas the selective β2‐AR agonist, salbutamol, promoted proliferation in vitro, suggesting that the β1‐AR may mediate the inhibitory effect of NE on preadipocyte proliferation. Taken together, we conclude that SNS activation suppresses preadipocyte proliferation via activation of the β1 AR in WAT.
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Affiliation(s)
- Mary K Schneider
- Department of Biology and Center for Obesity Reversal, Georgia State University, Atlanta, Georgia
| | - Bingzhong Xue
- Department of Biology and Center for Obesity Reversal, Georgia State University, Atlanta, Georgia
| | - Hang Shi
- Department of Biology and Center for Obesity Reversal, Georgia State University, Atlanta, Georgia
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16
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Keijer J, Li M, Speakman JR. What is the best housing temperature to translate mouse experiments to humans? Mol Metab 2019; 25:168-176. [PMID: 31003945 PMCID: PMC6599456 DOI: 10.1016/j.molmet.2019.04.001] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 04/01/2019] [Indexed: 12/20/2022] Open
Abstract
OBJECTIVES Ambient temperature impinges on energy metabolism in a body size dependent manner. This has implications for the housing temperature at which mice are best compared to humans. In 2013, we suggested that, for comparative studies, solitary mice are best housed at 23-25 °C, because this is 3-5 °C below the mouse thermoneutral zone and humans routinely live 3-5 °C below thermoneutrality, and because this generates a ratio of DEE to BMR of 1.6-1.9, mimicking the ratio found in free-living humans. METHODS Recently, Fischer et al. (2017) challenged this estimate. By studying mice at 21 °C and at 30 °C (but notably not at 23-25 °C) they concluded that 30 °C is the optimal housing temperature. Here, we measured energy metabolism of C57BL/6 mice over a range of temperatures, between 21.4 °C and 30.2 °C. RESULTS We observed a ratio of DEE to BMR of 1.7 at 27.6 °C and of 1.8 at 25.5 °C, suggesting that this is the best temperature range for housing C57BL/6 mice to mimic human thermal relations. We used a 24 min average to calculate the ratio, similar to that used in human studies, while the ratio calculated by Fisher et al. dependent on short, transient metabolic declines. CONCLUSION We concur with Fisher et al. and others that 21 °C is too cool, but we continue to suggest that 30 °C is too warm. We support this with other data. Finally, to mimic living environments of all humans, and not just those in controlled Western environments, mouse experimentation at various temperatures is likely required.
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Affiliation(s)
- Jaap Keijer
- Human and Animal Physiology, Wageningen University, De Elst 1, PO box 338, 6700 AH, Wageningen, the Netherlands.
| | - Min Li
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - John R Speakman
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China; Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, Scotland, UK; CAS Centre of Excellence in Animal Evolution and Genetics, Kunming, China.
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17
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Pahlavani M, Ramalingam L, Miller EK, Scoggin S, Menikdiwela KR, Kalupahana NS, Festuccia WT, Moustaid-Moussa N. Eicosapentaenoic Acid Reduces Adiposity, Glucose Intolerance and Increases Oxygen Consumption Independently of Uncoupling Protein 1. Mol Nutr Food Res 2019; 63:e1800821. [PMID: 30657255 DOI: 10.1002/mnfr.201800821] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 12/30/2018] [Indexed: 12/21/2022]
Abstract
SCOPE Brown adipose tissue (BAT) dissipates energy through uncoupling protein 1 (UCP1) and has been proposed as an anti-obesity target. It was reported previously that a high-fat (HF) diet enriched in eicosapentaenoic acid (EPA) significantly increased UCP1 and other thermogenic markers in BAT. It is hypothesized that these effects are mediated through UCP1-dependent regulation. METHODS AND RESULTS Wild-type (WT) and UCP1 knockout (KO) B6 male mice were housed at thermoneutrality and fed a HF diet, without or with eicosapentaenoic acid (EPA)-enriched fish oil. HF-fed KO mice were heavier and had higher BAT lipid content than other groups. Protective effects of EPA in WT, previously observed at 22 °C (reduced adiposity, improved glucose tolerance, and increased UCP1), disappeared at thermoneutrality. Mitochondrial proteins, cytochrome c oxidase subunit 1 (COX I), COX I, II, and IV were reduced in the KO mice compared to WT. Unexpectedly, EPA attenuated weight and fat mass gain and improved glucose tolerance in the KO mice. Finally, EPA increased BAT peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC1α) protein and gene expression, and whole-body oxygen consumption in KO mice, consistent with increased mitochondria DNA (mtDNA)/nuclear DNA (nucDNA) ratio. CONCLUSIONS EPA rescued the weight gain and glucose intolerance in UCP1 KO mice at thermoneutrality, independent of UCP1; these effects may be mediated in part via increased oxygen consumption and BAT PGC1α.
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Affiliation(s)
- Mandana Pahlavani
- Department of Nutritional Sciences and Obesity Research Cluster, Texas Tech University, Lubbock, TX, 79409, USA
| | - Latha Ramalingam
- Department of Nutritional Sciences and Obesity Research Cluster, Texas Tech University, Lubbock, TX, 79409, USA
| | - Emily K Miller
- Department of Nutritional Sciences and Obesity Research Cluster, Texas Tech University, Lubbock, TX, 79409, USA
| | - Shane Scoggin
- Department of Nutritional Sciences and Obesity Research Cluster, Texas Tech University, Lubbock, TX, 79409, USA
| | - Kalhara R Menikdiwela
- Department of Nutritional Sciences and Obesity Research Cluster, Texas Tech University, Lubbock, TX, 79409, USA
| | - Nishan S Kalupahana
- Department of Nutritional Sciences and Obesity Research Cluster, Texas Tech University, Lubbock, TX, 79409, USA.,Department of Physiology, Faculty of Medicine, University of Peradeniya, Peradeniya, 20400, Sri Lanka
| | - William T Festuccia
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, 05508, Brazil
| | - Naima Moustaid-Moussa
- Department of Nutritional Sciences and Obesity Research Cluster, Texas Tech University, Lubbock, TX, 79409, USA
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18
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Expression analysis of a cholecystokinin system in human and rat white adipose tissue. Life Sci 2018; 206:98-105. [PMID: 29800537 DOI: 10.1016/j.lfs.2018.05.036] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 05/13/2018] [Accepted: 05/21/2018] [Indexed: 01/22/2023]
Abstract
AIM Cholecystokinin (CCK) participates in the storage of dietary triglycerides in white adipose tissue (WAT). Our goal was to characterize, both in subcutaneous (Sc-WAT) and visceral WAT (Vis-WAT), the functional expression of the two known CCK receptors, CCK-1 (CCK-1R) and CCK-2 (CCK-2R), as well as of CCK. MAIN METHODS Gene and protein expression was assessed in different cell types of rat and human WAT by means of RT-PCR and western-blot, respectively. The functionality of CCK-Rs was tested by quantifying protein kinase B (Akt) phosphorylation after treatment of pre-adipocytes with the bioactive fragment of CCK, CCK-8. The CCK receptor subtype involved in Akt phosphorylation was investigated by using selective CCK-1R (SR-27,897) and CCK-2R antagonists (L-365,260). KEY FINDINGS In rats, CCK-1R (Cckar) and CCK-2R (Cckbr) gene expression was detected in the two types of WAT analyzed as well as in isolated adipocytes, mesenchymal stem cells and pre-adipocytes. CCK-1R and CCK-2R proteins were identified in adipocytes and, to a minor extent, in pre-adipocytes. In addition, CCK-2R were detected in subcutaneous mesenchymal stem cells. Gene expression of the CCK precursor preproCCK as well as CCK immunoreactivity were also found in Sc-WAT and Vis-WAT. In human WAT, CCK gene expression as well as CCK-2Rs and CCK were also identified. CCK-8 evoked Akt phosphorylation in rat pre-adipocytes, and this effect was antagonized by SR-27,897 and L-365,260. SIGNIFICANCE Our data show that both human and rat WAT express a complete CCK system, and suggest that CCK may have an autocrine/paracrine role in regulating adipose tissue biology.
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