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Huang X, He Q, Zhu H, Fang Z, Che L, Lin Y, Xu S, Zhuo Y, Hua L, Wang J, Zou Y, Huang C, Li L, Xu H, Wu D, Feng B. Hepatic Leptin Signaling Improves Hyperglycemia by Stimulating MAPK Phosphatase-3 Protein Degradation via STAT3. Cell Mol Gastroenterol Hepatol 2022; 14:983-1001. [PMID: 35863745 PMCID: PMC9490031 DOI: 10.1016/j.jcmgh.2022.07.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 07/12/2022] [Accepted: 07/12/2022] [Indexed: 01/31/2023]
Abstract
BACKGROUND & AIMS Obesity-related hyperglycemia, with hepatic insulin resistance, has become an epidemic disease. Central neural leptin signaling was reported to improve hyperglycemia. The aim of this study was to investigate the effect of hepatic leptin signaling on controlling hyperglycemia. METHODS First, the effect of leptin signaling on gluconeogenesis was investigated in primary mouse hepatocytes and hepatoma cells. Second, glucose tolerance, insulin tolerance, blood glucose levels, and hepatic gluconeogenic gene expression were analyzed in obese mice overexpressing hepatic OBRb. Third, expression of mitogen-activated protein kinase phosphatase (MKP)-3, phosphorylation level of signal transducer and activator of transcription (STAT) 3, and extracellular regulated protein kinase (ERK) were analyzed in hepatocytes and mouse liver. Fourth, the role of MKP-3 in hepatic leptin signaling regulating gluconeogenesis was analyzed. Lastly, the role of ERK and STAT3 in the regulation of MKP-3 protein by leptin signaling was analyzed. RESULTS Activation of hepatic leptin signaling suppressed gluconeogenesis in both hepatocytes and obese mouse liver, and improved hyperglycemia, insulin tolerance, and glucose tolerance in obese mice. The protein level of MKP-3, which can promote gluconeogenesis, was decreased by leptin signaling in both hepatocytes and mouse liver. Mkp-3 deficiency abolished the effect of hepatic leptin signaling on suppressing gluconeogenesis in hepatocytes. STAT3 decreased the MKP-3 protein level, while inactivation of STAT3 abolished the effect of leptin signaling on reducing the MKP-3 protein level in hepatocytes. Moreover, STAT3 could combine with MKP-3 and phospho-ERK1/2, which induced the degradation of MKP-3, and leptin signaling enhanced the combination. CONCLUSIONS Hepatic leptin signaling could suppress gluconeogenesis at least partially by decreasing the MKP-3 protein level via STAT3-enhanced MKP-3 and ERK1/2 combination.
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Affiliation(s)
- Xiaohua Huang
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, Sichuan, China,Key Laboratory of Animal Disease-Resistant Nutrition of Ministry of Education, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Qin He
- Hallett Center for Diabetes and Endocrinology, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, Rhode Island,School of international education, Xihua University, Chengdu, Sichuan, China
| | - Heng Zhu
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Zhengfeng Fang
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, Sichuan, China,Key Laboratory for Food Science and Human Health, College of Food Science, Sichuan Agricultural University, Ya’an, Sichuan, China
| | - Lianqiang Che
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Yan Lin
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Shengyu Xu
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Yong Zhuo
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Lun Hua
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Jianping Wang
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Yuanfeng Zou
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Chao Huang
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Lixia Li
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Haiyan Xu
- Hallett Center for Diabetes and Endocrinology, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, Rhode Island,Department of Quantitative Biosciences, Merck & Co., Inc., Boston, Massachusetts
| | - De Wu
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, Sichuan, China,Key Laboratory of Animal Disease-Resistant Nutrition of Ministry of Education, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Bin Feng
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, Sichuan, China,Key Laboratory of Animal Disease-Resistant Nutrition of Ministry of Education, Sichuan Agricultural University, Chengdu, Sichuan, China,Hallett Center for Diabetes and Endocrinology, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, Rhode Island,Key Laboratory for Food Science and Human Health, College of Food Science, Sichuan Agricultural University, Ya’an, Sichuan, China,Correspondence Address correspondence to: Bin Feng, PhD, Sichuan Agricultural University, 211 Huimin Road, Wenjiang District, Chengdu 611130, China. fax: (86) 028-82652669.
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Kasacka I, Piotrowska Ż, Domian N, Lewandowska A, Acewicz M. Immunohistochemical identification and assessment of the location of leptin, visfatin and chemerin in the liver of men with different body mass index. BMC Gastroenterol 2022; 22:233. [PMID: 35549673 PMCID: PMC9097377 DOI: 10.1186/s12876-022-02299-6] [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: 04/27/2021] [Accepted: 04/21/2022] [Indexed: 11/17/2022] Open
Abstract
Background Adipokines such as leptin, visfatin and chemerin play a pivotal role not only in the pathogenesis of excessive weight gain but also impact on hepatic metabolism. However, alterations in the production of these peptides in the liver of overweight individuals have not been fully elucidated yet. The aim of the study was to evaluate changes in leptin, visfatin and chemerin biosynthesis in the liver of men with different BMI. Methods Fourteen adult men without symptoms from the digestive system were recruited. Research material consisted of liver samples. Study participants were divided into two groups: lean (BMI ≤ 25 kg/m2) and overweight subjects (BMI > 25 kg/m2). Paraffin liver sections were processed by immunohistochemistry for detection of leptin, visfatin and chemerin. Hepatic expression of leptin, visfatin and chemerin genes was determined by qRT-PCR method. Results Increased immunoreactivity for leptin and chemerin, and decreased immunoreaction for visfatin were observed in the liver of overweight men in comparison to lean subjects. Overweight subjects with hepatic steatosis displayed increased immunoreactivity for leptin and weaker immunoreaction against visfatin and chemerin in the liver, compared to individuals with normal organ structure. Expression of leptin and chemerin was enhanced in the liver of overweight individuals, with the highest expression observed in subjects with hepatic steatosis. Conversely, expression of visfatin in the male liver was decreased in overweight subjects and those with and liver steatosis. Conclusions The present study proves that the expression of leptin, visfatin and chemerin in the male liver is altered in overweight individuals. Our report also indicates the potential importance of these peptides in hepatic steatosis associated with overweight.
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Affiliation(s)
- I Kasacka
- Department of Histology and Cytophysiology, Medical University of Białystok, Mickiewicza 2C Street, 15-222, Białystok, Poland.
| | - Ż Piotrowska
- Department of Histology and Cytophysiology, Medical University of Białystok, Mickiewicza 2C Street, 15-222, Białystok, Poland
| | - N Domian
- Department of Histology and Cytophysiology, Medical University of Białystok, Mickiewicza 2C Street, 15-222, Białystok, Poland
| | - A Lewandowska
- Department of Histology and Cytophysiology, Medical University of Białystok, Mickiewicza 2C Street, 15-222, Białystok, Poland
| | - M Acewicz
- Department of Histology and Cytophysiology, Medical University of Białystok, Mickiewicza 2C Street, 15-222, Białystok, Poland
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3
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Hussain Z, Khan JA. Food intake regulation by leptin: Mechanisms mediating gluconeogenesis and energy expenditure. ASIAN PAC J TROP MED 2017; 10:940-944. [PMID: 29111188 DOI: 10.1016/j.apjtm.2017.09.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 08/30/2017] [Accepted: 09/11/2017] [Indexed: 12/22/2022] Open
Abstract
Regulation of blood glucose levels and body fat is critical for survival. Leptin circulates freely in blood and controls body weight and food intake mainly through hypothalamic receptors and regulates glucose metabolism in the liver both directly through leptin receptors and indirectly via the hypothalamic receptors of central nervous system. Leptin affects food intake regulation and eventually glucose metabolism, lipometabolism, endocrine and immune functions, reproductive function, adipose tissue metabolism and energy expenditure. Leptin also exerts peripheral effects directly on glucose metabolism and gluconeogenesis. Most of obese human subjects have elevated plasma levels of leptin associated to the size of their total adipose tissue mass. Hence gluconeogenic function may be an essential factor in the regulation of nutritional intake and weight gain. The aim of this review is therefore to identify and module the possible effects of leptin with special application in gluconeogenesis. In addition, this review includes the study of fat consumption and energy expenditure in the body. Specific modulation of leptin receptors and adipose tissues functioning could have important inference on therapeutic strategies.
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Affiliation(s)
- Zulfia Hussain
- Institute of Pharmacy, Physiology and Pharmacology, University of Agriculture, Faisalabad, 38040, Pakistan
| | - Junaid Ali Khan
- Institute of Pharmacy, Physiology and Pharmacology, University of Agriculture, Faisalabad, 38040, Pakistan.
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Gutierrez-Repiso C, Garcia-Serrano S, Moreno-Ruiz FJ, Alcain-Martinez G, Rodriguez-Pacheco F, Garcia-Fuentes E. Jejunal gluconeogenesis associated with insulin resistance level and its evolution after Roux-en-Y gastric bypass. Surg Obes Relat Dis 2017; 13:623-630. [DOI: 10.1016/j.soard.2016.11.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 09/28/2016] [Accepted: 11/26/2016] [Indexed: 01/16/2023]
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Voss SC, Nikolovski Z, Bourdon PC, Alsayrafi M, Schumacher YO. The effect of cumulative endurance exercise on leptin and adiponectin and their role as markers to monitor training load. Biol Sport 2015; 33:23-8. [PMID: 26985130 PMCID: PMC4786583 DOI: 10.5604/20831862.1180173] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2015] [Revised: 07/31/2015] [Accepted: 10/07/2015] [Indexed: 12/02/2022] Open
Abstract
Leptin and adiponectin play an essential role in energy metabolism. Leptin has also been proposed as a marker for monitoring training load. So far, no studies have investigated the variability of these hormones in athletes and how they are regulated during cumulative exercise. This study monitored leptin and adiponectin in 15 endurance athletes twice daily in the days before, during and after a 9-day simulated cycling stage race. Adiponectin significantly increased during the race (p = 0.001) and recovery periods (p = 0.002) when compared to the baseline, while leptin decreased significantly during the race (p < 0.0001) and returned to baseline levels during the recovery period. Intra-individual variability was substantially lower than inter-individual variability for both hormones (leptin 34.1 vs. 53.5%, adiponectin 19% vs. 37.2%). With regards to exercise, this study demonstrated that with sufficient, sustained energy expenditure, leptin concentrations can decrease within the first 24 hours. Under the investigated conditions there also appears to be an optimal leptin concentration which ensures stable energy homeostasis, as there was no significant decrease over the subsequent race days. In healthy endurance athletes the recovery of leptin takes 48-72 hours and may even show a supercompensation-like effect. For adiponectin, significant increases were observed within 5 days of commencing racing, with these elevated values failing to return to baseline levels after 3 days of recovery. Additionally, when using leptin and adiponectin to monitor training loads, establishing individual threshold values improves their sensitivity.
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Affiliation(s)
- S C Voss
- Anti-Doping Lab Qatar, Doha, Qatar
| | - Z Nikolovski
- Aspire Academy, Sport Science Department, Doha, Qatar
| | - P C Bourdon
- Aspire Academy, Sport Science Department, Doha, Qatar; University of South Australia, School of Health Sciences, Adelaide, Australia
| | | | - Y O Schumacher
- Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Qatar
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Zhou X, Cheung CM, Yang JM, Or PMY, Lee WYW, Yeung JHK. Danshen (Salvia miltiorrhiza) water extract inhibits paracetamol-induced toxicity in primary rat hepatocytes via reducing CYP2E1 activity and oxidative stress. J Pharm Pharmacol 2015; 67:980-9. [PMID: 25645193 DOI: 10.1111/jphp.12381] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Accepted: 12/07/2014] [Indexed: 12/22/2022]
Abstract
OBJECTIVES This study aimed to investigate the protective effects of Danshen (Salvia miltiorrhiza) water extract (DSE) and its major phenolic acid components against CYP2E1-mediated paracetamol (APAP)-induced hepatic toxicity. METHODS The protection and underlying mechanisms were detected in CYP2E1 overexpression primary rat hepatocytes by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, alamar blue assay, CYP2E1 inhibition assay and glutathione assay. KEY FINDINGS After APAP treatment, DSE (0.06-1 mg/ml) significantly increased cell viability in MTT assay. Two major components danshensu (8.2-130.5 μm) and salvianolic acid B (Sal B; 3.3-53.5 μm) mainly contributed to this protection, but rosmarinic acid, protocatechuic aldehyde and Sal A did not. Alamar blue assay showed that DSE, danshensu and Sal B maintained mitochondrial metabolic activity. DSE inhibited CYP2E1 (Ki = 1.46 mg/ml) in a mixed mode in rat liver microsomes in vitro; DSE decreased APAP-induced total glutathione depletion and preserved redox status (GSH/GSSG ratio) in hepatocytes. Danshensu and Sal B did not inhibit CYP2E1 or decrease total glutathione depletion, but preserved redox status. CONCLUSIONS DSE protected hepatocytes against APAP-induced injury via maintenance of mitochondrial metabolic activity, CYP2E1 inhibition, reduction of total glutathione depletion and preservation of redox status. Danshensu and Sal B were mainly responsible for this protection.
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Affiliation(s)
- Xuelin Zhou
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Ching Mei Cheung
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Jia-Ming Yang
- School of Chinese Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Penelope M Y Or
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Wayne Y W Lee
- Department of Orthopaedics & Traumatology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - John H K Yeung
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
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7
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Davidson MD, Lehrer M, Khetani SR. Hormone and Drug-Mediated Modulation of Glucose Metabolism in a Microscale Model of the Human Liver. Tissue Eng Part C Methods 2015; 21:716-25. [PMID: 25517416 DOI: 10.1089/ten.tec.2014.0512] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Due to its central role in glucose homeostasis, the liver is an important target for drug development efforts for type 2 diabetes mellitus (T2DM). Significant differences across species in liver metabolism necessitate supplementation of animal data with assays designed to assess human-relevant responses. However, isolated primary human hepatocytes (PHHs) display a rapid decline in phenotypic functions in conventional monolayer formats. Cocultivation of PHHs with specific stromal cells, especially in micropatterned configurations, can stabilize some liver functions for ~4 weeks in vitro. However, it remains unclear whether coculture approaches can stabilize glucose metabolism that can be modulated with hormones in PHHs. Thus, in this study, we compared commonly employed conventional culture formats and previously developed micropatterned cocultures (MPCCs) of cryopreserved PHHs and stromal fibroblasts for mRNA expression of key glucose metabolism genes (i.e., phosphoenolpyruvate carboxykinase-1 [PCK1]) and sensitivity of gluconeogenesis to prototypical hormones, insulin and glucagon. We found that only MPCCs displayed high expression of all transcripts tested for at least 2 weeks and robust gluconeogenesis with responsiveness to hormones for at least 3 weeks in vitro. Furthermore, MPCCs displayed glycogen storage and lysis, which could be modulated with hormones under the appropriate feeding and fasting states, respectively. Finally, we utilized MPCCs in proof-of-concept experiments where we tested gluconeogenesis inhibitors and evaluated the effects of stimulation with high levels of glucose as in T2DM. Gluconeogenesis in MPCCs was decreased after stimulation with drugs (i.e., metformin) and the PHHs accumulated significant amount of lipids following incubation with excess glucose (i.e., 340% in 50 mM glucose relative to physiologic 5 mM glucose controls). In conclusion, MPCCs provide a platform to study glucose metabolism and hormonal responsiveness in cryopreserved PHHs from multiple donors for several weeks in vitro. This model is also useful to study the effects of drugs and overnutrition for applications in T2DM.
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Affiliation(s)
- Matthew D Davidson
- 1 School of Biomedical Engineering, Colorado State University , Fort Collins, Colorado
| | - Michael Lehrer
- 2 Department of Biomedical Sciences, Colorado State University , Fort Collins, Colorado
| | - Salman R Khetani
- 1 School of Biomedical Engineering, Colorado State University , Fort Collins, Colorado.,3 Department of Mechanical Engineering, Colorado State University , Fort Collins, Colorado
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8
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Lei MM, Wu SQ, Shao XB, Li XW, Chen Z, Ying SJ, Shi ZD. Creating leptin-like biofunctions by active immunization against chicken leptin receptor in growing chickens. Domest Anim Endocrinol 2015; 50:55-64. [PMID: 25447880 DOI: 10.1016/j.domaniend.2014.09.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Revised: 09/01/2014] [Accepted: 09/04/2014] [Indexed: 12/19/2022]
Abstract
In this study, immunization against chicken leptin receptor (cLEPR) extracellular domain (ECD) was applied to investigate leptin regulation and LEPR biofunction in growing chicken pullets. A recombinant protein (cLEPR ECD) based on the cLEPR complemenary DNA sequence corresponding to the 582nd to 796th amino acid residues of cLEPR mature peptide was prepared and used as antigen. Immunization against cLEPR ECD in growing chickens increased anti-cLEPR ECD antibody titers in blood, enhanced proportions of phosphorylated janus kinase 2 (JAK2) and served as signal transducer and activator of transcription 3 (STAT3) protein in liver tissue. Chicken live weight gain and abdominal fat mass were significantly decreased (P < 0.05), but feed intake was stimulated by cLEPR ECD immunization (P < 0.05). The treatment also upregulated the gene expression levels of lepR, AMP-activated protein kinase (AMPK), acetyl CoA carboxylase-2 (ACC2), and uncoupling protein 3 (UCP3) in liver, abdominal fat, and breast muscle (P < 0.05) but decreased fasn expression levels (P < 0.01). Apart from that of lepR, the expression of appetite-regulating genes, such as orexigenic genes, agouti-related peptide (AgRP) and neuropeptide Y (NPY), were upregulated (P < 0.01), whereas the anorexigenic gene proopiomelanocortin (POMC) was downregulated in the hypothalamic tissue of cLEPR-immunized pullets (P < 0.01). Blood concentrations of metabolic molecules, such as glucose, triglycerides, and very-low-density lipoprotein, were significantly decreased in cLEPR-immunized pullets but those of cholesterol, high-density lipoprotein, and low-density lipoprotein increased. These results demonstrate that antibodies to membrane proximal cLEPR ECD enhance cLEPR signal transduction, which stimulates metabolism and reduces fat deposition in chickens.
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Affiliation(s)
- M M Lei
- Laboratory of Animal Breed Improvement and Reproduction, Institute of Animal Science, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - S Q Wu
- College of Animal Sciences, South China Agricultural University, Guangzhou, 510642, China
| | - X B Shao
- Institute of Guagndong Province Poultry Technology, Guangzhou, 510520, China
| | - X W Li
- College of Animal Sciences, South China Agricultural University, Guangzhou, 510642, China
| | - Z Chen
- Laboratory of Animal Breed Improvement and Reproduction, Institute of Animal Science, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - S J Ying
- Laboratory of Animal Breed Improvement and Reproduction, Institute of Animal Science, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - Z D Shi
- Laboratory of Animal Breed Improvement and Reproduction, Institute of Animal Science, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China.
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Abstract
The fat‐derived hormone, leptin, is well known to regulate body weight. However, there is now substantial evidence that leptin also plays a primary role in the regulation of glucose homeostasis, independent of actions on food intake, energy expenditure or body weight. As such, leptin might have clinical utility in treating hyperglycemia, particularly in conditions of leptin deficiency, such as lipodystrophy and diabetes mellitus. The mechanisms through which leptin modulates glucose metabolism have not been fully elucidated. Leptin receptors are widely expressed in peripheral tissues, including the endocrine pancreas, liver, skeletal muscle and adipose, and both direct and indirect leptin action on these tissues contributes to the control of glucose homeostasis. Here we review the role of leptin in glucose homeostasis, along with our present understanding of the mechanisms involved. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2012.00203.x, 2012)
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Affiliation(s)
- Heather C Denroche
- Department of Cellular and Physiological Sciences, The Life Sciences Institute
| | - Frank K Huynh
- Department of Cellular and Physiological Sciences, The Life Sciences Institute
| | - Timothy J Kieffer
- Department of Cellular and Physiological Sciences, The Life Sciences Institute ; Department of Surgery, University of British Columbia, Vancouver, British Columbia, Canada
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Bravard A, Vial G, Chauvin MA, Rouillé Y, Bailleul B, Vidal H, Rieusset J. FTO contributes to hepatic metabolism regulation through regulation of leptin action and STAT3 signalling in liver. Cell Commun Signal 2014; 12:4. [PMID: 24410832 PMCID: PMC3896784 DOI: 10.1186/1478-811x-12-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Accepted: 01/04/2014] [Indexed: 11/10/2022] Open
Abstract
Background The fat mass and obesity associated (FTO) gene is related to obesity and type 2 diabetes, but its function is still largely unknown. A link between leptin receptor-signal transducers and activators of transcription 3 (LepR-STAT3) signalling pathway and FTO was recently suggested in the hypothalamus. Because of the presence of FTO in liver and the role of LepR-STAT3 in the control of hepatic metabolism, we investigated both in vitro and in vivo the potential interrelationship between FTO and LepR-STAT3 signalling pathway in liver and the impact of FTO overexpression on leptin action and glucose homeostasis in liver of mice. Results We found that FTO protein expression is regulated by both leptin and IL-6, concomitantly to an induction of STAT3 tyrosine phosphorylation, in leptin receptor (LepRb) expressing HuH7 cells. In addition, FTO overexpression in vitro altered both leptin-induced Y705 and S727 STAT3 phosphorylation, leading to dysregulation of glucose-6-phosphatase (G6P) expression and mitochondrial density, respectively. In vivo, liver specific FTO overexpression in mice induced a reducetion of Y705 phosphorylation of STAT3 in nuclear fraction, associated with reduced SOCS3 and LepR mRNA levels and with an increased G6P expression. Interestingly, FTO overexpression also induced S727 STAT3 phosphorylation in liver mitochondria, resulting in an increase of mitochondria function and density. Altogether, these data indicate that FTO promotes mitochondrial recruitment of STAT3 to the detriment of its nuclear localization, affecting in turn oxidative metabolism and the expression of leptin-targeted genes. Interestingly, these effects were associated in mice with alterations of leptin action and hyperleptinemia, as well as hyperglycemia, hyperinsulinemia and glucose intolerance. Conclusions Altogether, these data point a novel regulatory loop between FTO and leptin-STAT3 signalling pathways in liver cells, and highlight a new role of FTO in the regulation of hepatic leptin action and glucose metabolism.
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Affiliation(s)
| | | | | | | | | | | | - Jennifer Rieusset
- INSERM U-1060, Laboratoire CarMeN, Université Lyon 1, INRA 1235, INSA de Lyon, Facultés de médecine Charles Mérieux, Lyon-Sud, Oullins, France.
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Li Y, Li X, Song Y, Shi X, Ding H, Yang W, Liu Z, Chen H, Li X, Wang J, Liu G, Wang Z. Effect of leptin on the gluconeogenesis in calf hepatocytes cultured in vitro. Cell Biol Int 2013; 37:1350-3. [PMID: 23956103 DOI: 10.1002/cbin.10172] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 07/12/2013] [Indexed: 12/21/2022]
Abstract
We have investigated the effect of leptin on gluconeogenesis in the liver. Hepatocytes were cultured and treated with 0, 2.5, 5, 10, 50, 100 ng/mL of leptin in groups I, II, III, IV, V, and VI, respectively. mRNA expression and enzyme activity of pyruvate carboxylase and phosphoenolpyruvate carboxykinase were determined by real-time fluorescence quantitative RT-PCR and biochemical kits, respectively. Compared with group I, mRNA expression of pyruvate carboxylase and phosphoenolpyruvate carboxykinase in groups III, IV, V, and VI were significantly lower (P < 0.01). Pyruvate carboxylase and phosphoenolpyruvate carboxykinase enzyme activity decreased significantly (P < 0.05) when leptin concentration exceeded 5 and 10 ng/mL, respectively. These results indicate that leptin markedly downregulated mRNA expression and enzyme activity of pyruvate carboxylase and phosphoenolpyruvate carboxykinase in hepatocytes, which suggests that high concentrations of LP inhibit hepatocyte gluconeogenesis, thus making negative energy balance more serious.
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Affiliation(s)
- Yu Li
- College of Animal Science and Veterinary Medicine, Jilin University, 5333 Xi'an Road, Changchun, Jilin, 130062, China
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Leptin-mediated reactive oxygen species production does not significantly affect primary mouse hepatocyte functions in vitro. Eur J Gastroenterol Hepatol 2012; 24:1370-80. [PMID: 22895388 DOI: 10.1097/meg.0b013e328357ce1c] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
AIM Direct and indirect effects of leptin on hepatic stellate cells (HSCs) have been documented in the literature, whereas little is known about leptin's actions on hepatocytes. Leptin mediates its profibrogenic and proinflammatory effects on HSCs in part through the production of intracellular reactive oxygen species (ROS). In this study, we focus our analysis on leptin-induced ROS production in hepatocytes. METHODS The expression of leptin receptor isoforms on primary mouse liver cells was examined by real-time quantitative-PCR and western blotting. Cultures were exposed to leptin in combination with inhibitors for reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, MAP kinase/ERK kinase 1 (MEK1) or janus kinase 2 (JAK2). ROS levels were quantified by measuring fluorescence. The effects of leptin on hepatocyte functions and programmed cell death were evaluated by fluorescent or luminescent assays. RESULTS Leptin induced ROS production in primary hepatocytes by 150-450%, compared with a 20-30% increase in HSCs and liver sinusoidal endothelial cells (LSECs). This ROS production could be inhibited by NADPH oxidase, MEK1 and JAK2 inhibitors. Western blotting indicated that mouse HSCs and LSECs mainly express short leptin receptor isoforms, whereas hepatocytes appeared to express both short and long isoform(s). Leptin-induced ROS production in db/db hepatocytes did not differ from wild-type mice. Finally, leptin had no negative influence on primary hepatocyte functions. CONCLUSION Leptin induced higher ROS levels in primary hepatocytes than in LSECs and HSCs, depending on NADPH oxidase, MEK1 and JAK2 signalling but not on the long leptin receptor isoform. Furthermore, leptin exposure did not influence primary hepatocyte functionality negatively.
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Jitrapakdee S. Transcription factors and coactivators controlling nutrient and hormonal regulation of hepatic gluconeogenesis. Int J Biochem Cell Biol 2012; 44:33-45. [DOI: 10.1016/j.biocel.2011.10.001] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Revised: 09/30/2011] [Accepted: 10/04/2011] [Indexed: 12/17/2022]
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Lu Y, Zhang G, Shen C, Uygun K, Yarmush ML, Meng Q. A novel 3D liver organoid system for elucidation of hepatic glucose metabolism. Biotechnol Bioeng 2011; 109:595-604. [PMID: 22006574 DOI: 10.1002/bit.23349] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Revised: 09/26/2011] [Accepted: 09/29/2011] [Indexed: 12/12/2022]
Abstract
Hepatic glucose metabolism is a key player in diseases such as obesity and diabetes as well as in antihyperglycemic drugs screening. Hepatocytes culture in two-dimensional configurations is limited in vitro model for hepatocytes to function properly, while truly practical platforms to perform three-dimensional (3D) culture are unavailable. In this work, we present a practical organoid culture method of hepatocytes for elucidation of glucose metabolism under nominal and stress conditions. Employing this new method of culturing cells within a hollow fiber reactor, hepatocytes were observed to self-assemble into 3D spherical organoids with preservation of tight junctions and display increased liver-specific functions. Compared to both monolayer culture and sandwich culture, the hepatocyte organoids displayed higher intracellular glycogen content, glucose consumption, and gluconeogenesis and approached the in vivo values, as also confirmed by gene expression of key enzymes. Moreover, hepatocyte organoids demonstrated more realistic sensitivity to hormonal challenges with insulin, glucagon, and dexamethasone. Finally, the exposure to high glucose demonstrated toxicities including alteration of mitochondrial membrane potential, lipid accumulation, and reactive oxygen species formation, similar to the in vivo responses, which was not captured by monolayer cultures. Collectively, hepatocyte organoids mimicked the in vivo functions better than hepatocyte monolayer and sandwich cultures, suggesting suitability for applications such as antihyperglycemic drugs screening.
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Affiliation(s)
- Yanhua Lu
- Department of Chemical and Biological Engineering, Zhejiang University, 38 Zheda Road, Hangzhou, Zhejiang 310027, China
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15
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Sparks JD, Cianci J, Jokinen J, Chen LS, Sparks CE. Interleukin-6 mediates hepatic hypersecretion of apolipoprotein B. Am J Physiol Gastrointest Liver Physiol 2010; 299:G980-9. [PMID: 20651008 PMCID: PMC2957334 DOI: 10.1152/ajpgi.00080.2010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Obesity and type 2 diabetes are associated with insulin resistance (IR), increased circulating proinflammatory cytokines, and hypertriglyceridemia, the latter being caused by overproduction of hepatic very low density lipoprotein (VLDL). One cytokine strongly linked with development of hepatic IR is interleukin-6 (IL-6). Our objective was to evaluate IL-6 effects on hepatic apolipoprotein B (apoB) and VLDL secretion and to examine possible linkages between cytokine signaling and insulin-suppressive effects on lipoprotein secretion. Of the cytokines examined, only IL-6 stimulated secretion of apoB-containing lipoproteins in a dose-dependent manner. Both B100 and B48 secretion were significantly increased in VLDL and in lipoproteins with a density >1.019 g/ml. The ability of insulin to suppress hepatic apoB secretion was maintained in hepatocytes treated with IL-6. Pulse-chase studies indicated that enhanced apoB synthesis was the primary mechanism for increased lipoprotein secretion, which corresponded with higher abundance of apoB mRNA. Because IL-6 did not alter the decay rate of apoB mRNA transcripts, results support that increased apoB mRNA levels are the result of enhanced apob gene transcription. Increased apoB-lipoprotein secretion was also detected with oncostatin M (OSM), supporting involvement of the signal-transducing protein, gp130. Increased suppressor of cytokine signaling (SOCS) 3 expression negated IL-6 and OSM effects and significantly reduced cellular apoB mRNA abundance. We conclude that IL-6 favors secretion of apoB-containing lipoproteins by increasing availability of apoB through changes in apob gene transcription. These changes may contribute to hypersecretion of VLDL associated with obesity, particularly under conditions where SOCS3 is not overexpressed to an extent capable of overcoming IL-6-stimulated apob gene transcription.
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Affiliation(s)
- Janet D. Sparks
- Department of Pathology and Laboratory Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York
| | - Joanne Cianci
- Department of Pathology and Laboratory Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York
| | - Jenny Jokinen
- Department of Pathology and Laboratory Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York
| | - Li Sheng Chen
- Department of Pathology and Laboratory Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York
| | - Charles E. Sparks
- Department of Pathology and Laboratory Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York
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16
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Wang X, Lee WYW, Or PMY, Yeung JHK. Pharmacokinetic interaction studies of tanshinones with tolbutamide, a model CYP2C11 probe substrate, using liver microsomes, primary hepatocytes and in vivo in the rat. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2010; 17:203-211. [PMID: 19679455 DOI: 10.1016/j.phymed.2009.07.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2009] [Revised: 06/26/2009] [Accepted: 07/16/2009] [Indexed: 05/28/2023]
Abstract
The effects of Danshen and its active components (tanshinone I, tanshinone IIA, dihydrotanshinone and cryptotanshinone) on tolbutamide 4-hydroxylation was investigated in the rat. Danshen (0.125-2mg/ml) decreased 4-hydroxy-tolbutamide formation in vitro and in vivo. Enzyme kinetics studies showed that inhibition of tolbutamide 4-hydroxylase activity was competitive and concentration-dependent. The K(i) values of the tanshinones were: dihydrotanshinone (8.92microM), cryptotanshinone (24.5microM), tanshinone I (80.3microM) and tanshinone IIA (242.9microM). In freshly prepared primary rat hepatocytes, tanshinones inhibited tolbutamide 4-hydroxylation in a concentration-dependent manner, with EC(40) values in the order: cryptotanshinone (15.8microM), tanshinone IIA (16.2microM), dihydrotanshinone (20.1microM) and tanshinone I (48.2microM). In whole animal studies, single dose Danshen treatment (50 or 200mg/kg, i.p.) increased tolbutamide clearance (17-26.9%), decreased AUC (14.4-20.9%) and increased the Vd (7.26%). Three-day Danshen treatment (200mg/kg/day, i.p.) decreased the C(initial), increased T(1/2) and Vd but did not affect tolbutamide clearance and AUC. Tolbutamide-4-hydroxylation in vivo was decreased by Danshen after acute and after 3-day treatment, with decreases in the AUC of 4-hydroxy-tolbutamide (15-28%) over the time period studied. Despite competitive inhibition of rat CYP2C11 in vitro and in vivo, as shown by the decrease in tolbutamide 4-hydroxylation, only minor changes in tolbutamide pharmacokinetics was observed. This study illustrated that the herb-drug interaction potential should be monitored by both in vitro and in vivo biotransformation/ pharmacokinetic parameters.
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Affiliation(s)
- X Wang
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, China
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17
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IGF-I mediated inhibition of leptin receptor expression in porcine hepatocytes. Comp Biochem Physiol B Biochem Mol Biol 2010; 155:43-8. [DOI: 10.1016/j.cbpb.2009.09.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2008] [Revised: 09/18/2009] [Accepted: 09/21/2009] [Indexed: 11/21/2022]
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Caperna TJ, Shannon AE, Garrett WM. A gel-based reference map of the porcine hepatocyte proteome. Domest Anim Endocrinol 2008; 35:142-56. [PMID: 18538972 DOI: 10.1016/j.domaniend.2007.12.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2006] [Revised: 12/21/2007] [Accepted: 12/22/2007] [Indexed: 01/28/2023]
Abstract
The overall goal of our research is to characterize and identify gene expression profiles of porcine hepatic cells. In this study, we have prepared two-dimensional electrophoresis maps of cytosol and membrane fractions from freshly prepared hepatocytes which were pooled from three crossbred pigs (35-69kg). Following isoelectric focusing with three pH range immobilized pH gradient strips (pH 3-6, 5-8 and 7-10) and staining the second dimension gels with colloidal Coomassie blue, 728 protein spots were picked and digested with trypsin. Extracted tryptic peptides were initially subjected to matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS) analysis for identification of proteins by peptide mass fingerprinting (PMF). Proteins which were not identified by PMF were analyzed by liquid chromatography-tandem MS. Utilizing publicly available databases [NCBInr, Swiss Prot and expressed sequence tags (EST)], 648 proteins were identified. Of those, 282 were unique proteins and greater than 90% of proteins spots contained single proteins. These data represent the first comprehensive proteomic analysis of porcine hepatocytes and will provide a database for future investigations of endocrine regulation of gene expression and metabolic processes in vitro.
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Affiliation(s)
- Thomas J Caperna
- Animal Biosciences and Biotechnology Laboratory, Animal and Natural Resources Institute, U.S. Department of Agriculture-Agricultural Research Service, Beltsville Agricultural Research Center, Beltsville, MD 20705, USA.
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Ramsay TG, Richards MP. Leptin and leptin receptor expression in skeletal muscle and adipose tissue in response to in vivo porcine somatotropin treatment. J Anim Sci 2006; 83:2501-8. [PMID: 16230646 DOI: 10.2527/2005.83112501x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The present study was performed to examine the response of leptin and leptin receptor (Rb) genes to porcine somatotropin (pST) stimuli in finishing pigs. Twelve crossbred barrows (Yorkshire x Landrace) were used in this study. Animals were individually fed a basal diet containing 18% CP, 1.2% lysine, and 3.5 Mcal of DE/kg ad libitum (as-fed basis). At 90 kg, six pigs were treated with daily injections of recombinant pST (10 mg) in sterile bicarbonate buffer, whereas the other six pigs were injected with sterile bicarbonate buffer (controls). With initiation of pST treatment, the quantity of feed offered was 85% of calculated ad libitum intake based on BW and adjusted every 3 d. Diet restriction was designed to correct for the effects of the known inhibition in feed intake because of pST treatment in swine. Animals were maintained on treatment for 2 wk. A blood sample was obtained from each pig on d 14 of treatment, 6 h after pST injection. Tissue samples were collected on d 15, frozen in liquid N2, and stored at -80 degrees C before analysis for mRNA abundance. Total RNA was amplified by reverse transcription (RT) PCR with subsequent quantification of transcripts by capillary electrophoresis with laser-induced fluorescence detection. Samples included outer subcutaneous adipose tissue (OSQ), middle subcutaneous adipose tissue (MSQ), leaf fat (LF), liver, latissimus dorsi (LD), and biceps femoris (BF). Restricted feeding resulted in no change in BW of control pigs, whereas pST treatment increased BW by 6.9 +/- 0.5 kg (P < 0.001). Treatment with pST produced a 12-fold increase in serum ST concentration relative to control pigs (P < 0.002). Serum leptin concentration was increased by 17% in swine treated with pST relative to control pigs (P < 0.011). Leptin mRNA abundance was increased in liver by pST treatment (P < 0.05). Administration of pST decreased leptin Rb (Ob-Rb) mRNA abundance by 27% in liver (P < 0.044) and by 49.5% in OSQ (P < 0.025) relative to controls. The present data suggest that pST does not affect leptin expression independent of dietary intake because the restricted feeding regimen used in the present study precluded detection of major change in leptin gene expression. Changes in Ob-Rb mRNA abundance by pST treatment indicate that ST or the metabolic adaptations to ST have a role in regulating Ob-Rb expression.
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Affiliation(s)
- T G Ramsay
- Growth Biology Laboratory, USDA-ARS, Beltsville, MD 20705, USA.
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Caperna TJ, Shannon AE, Poch SM, Garrett WM, Richards MP. Hormonal regulation of leptin receptor expression in primary cultures of porcine hepatocytes. Domest Anim Endocrinol 2005; 29:582-92. [PMID: 16213991 DOI: 10.1016/j.domaniend.2005.03.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2005] [Revised: 03/08/2005] [Accepted: 03/19/2005] [Indexed: 10/25/2022]
Abstract
A study was conducted to elucidate hormonal control of leptin receptor gene expression in primary cultures of porcine hepatocytes. Hepatocytes were isolated from pigs (52 kg) and seeded into collagen-coated T-25 flasks. Monolayer cultures were established in medium containing fetal bovine serum for 1 day and switched to a serum-free medium for the remainder of the 3-day culture period. To establish basal conditions hepatocytes were maintained in serum-free William's E medium containing 10 nM dexamethasone and 1 ng/ml insulin. For the final 24 h, insulin (1 or 100 ng/ml) or glucagon (100 ng/ml), were added in the presence or absence of 100 nM triiodothyronine (T3). RNA was extracted and quantitative RT-PCR was performed with primers specific for the long form and total porcine leptin receptors. Leptin receptor expression was calculated relative to co-amplified 18S rRNA. Expression of the long form of the leptin receptor was confirmed under basal conditions. Insulin, glucagon and synthetic human proteins (ghrelin and GLP-1) at 100 ng/ml had no influence on leptin receptor expression; the addition of T3 was associated with a marked increase (P < 0.001) in expression of total and long forms of the leptin receptor by 1.6 and 2.4-fold, respectively. Addition of leptin to cells which were pre-treated with T3 for 24 h (to up-regulate leptin receptor expression), confirmed the lack of a direct effect of leptin on glucagon-induced glycogen turnover and cAMP production. These data suggest that porcine hepatocytes may be insensitive to leptin stimulation even when leptin receptor expression is enhanced by T3.
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Affiliation(s)
- T J Caperna
- Growth Biology Laboratory, Animal and Natural Resources Institute, Beltsville Agricultural Research Center, USDA-ARS, Bulding 200, Room 202, BARC-East, Beltsville, MD 20705, USA.
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