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Ge SX, Li G, Ryan AS. Effects of Weight Loss and Aerobic Exercise Training on Adi-Pose Tissue Zinc α2-Glycoprotein and Associated Genes in Obesity. Cells 2023; 12:2366. [PMID: 37830580 PMCID: PMC10571564 DOI: 10.3390/cells12192366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 08/30/2023] [Accepted: 09/25/2023] [Indexed: 10/14/2023] Open
Abstract
Zinc α2-glycoprotein (ZAG) has been implicated in fatty acid metabolism and utilization and is lower in obese and higher in cachexic adults compared to those of normal weight. Previous studies suggest that ZAG binds to the beta3-adrenergic receptor (β3AR) to influence fatty acid metabolism in adipose tissue by regulating hormone sensitive lipase (HSL). The purpose of this study is to investigate the effects of a six-month weight loss (WL) or aerobic exercise (AEX) intervention on adipose tissue and skeletal muscle ZAG mRNA levels and protein expression, as well as the expression of β3AR, and HSL. Abdominal adipose tissue (AB) and gluteal adipose tissue (Glut) and vastus lateralis muscle biopsies were performed before and after WL (n = 13) or AEX (n = 13). ZAG, HSL, and β3AR expressions were determined by RT-PCR, and ZAG and HSL plasma levels by ELISA. Body weight decreased by 9.69% (p < 0.001) in WL and did not change with AEX. Maximal oxygen consumption (VO2max) increased by 7.1% (p < 0.005) after WL and by 16.69% (p < 0.001) after AEX. WL significantly decreased body weight with a reduction of percentage of fat, fat mass, fat-free mass (FFM). AEX decreased percent fat and increased VO2max, but did not change fat mass and FFM. Abdominal ZAG and HSL mRNA levels did not change significantly after WL or AEX. There were no changes in plasma ZAG, HSL and adipose tissue β3AR mRNA levels after WL and AEX. ZAG, HSL and β3AR mRNA expressions in adipose tissue are positively associated each other. Adipose tissue abdominal and gluteal HSL are negatively associated with HOMA-IR (Homeostatic Model Assessment for Insulin Resistance), and both ZAG and HSL adipose tissue are negatively associated with fasting glucose and the glucose area under the curve. Further work is needed to elucidate the role of ZAG and HSL in the propensity for weight gain and the ability of exercise to mitigate these responses.
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Affiliation(s)
- Shealinna X. Ge
- Department of Dermatology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Guoyan Li
- Division of Gerontology and Palliative Medicine, Department of Medicine, University of Maryland School of Medicine, 655 W Baltimore Street, Baltimore, MD 21201, USA
| | - Alice S. Ryan
- Division of Gerontology and Palliative Medicine, Department of Medicine, University of Maryland School of Medicine, 655 W Baltimore Street, Baltimore, MD 21201, USA
- Baltimore VA Medical Center, Geriatric Research, Education and Clinical Center (GRECC), 10 N Greene Street, Baltimore, MD 21201, USA
- VA Research Service, VA Maryland Health Care System, 10 N Greene Street, Baltimore, MD 21201, USA
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Abstract
Sodium glucose cotransporter 2 (SGLT-2) inhibitors are the latest class of antidiabetic medications. They prevent glucose reabsorption in the proximal convoluted tubule to decrease blood sugar. Several animal studies revealed that SGLT-2 is profoundly involved in the inflammatory response, fibrogenesis, and regulation of numerous intracellular signaling pathways. Likewise, SGLT-2 inhibitors markedly attenuated inflammation and fibrogenesis and improved the function of damaged organ in animal studies, observational studies, and clinical trials. SGLT-2 inhibitors can decrease blood pressure and ameliorate hypertriglyceridemia and obesity. Likewise, they improve the outcome of cardiovascular diseases such as heart failure, arrhythmias, and ischemic heart disease. SGLT-2 inhibitors are associated with lower cardiovascular and all-cause mortality as well. Meanwhile, they protect against nonalcoholic fatty liver disease (NAFLD), chronic kidney disease, acute kidney injury, and improve micro- and macroalbuminuria. SGLT-2 inhibitors can reprogram numerous signaling pathways to improve NAFLD, cardiovascular diseases, and renal diseases. For instance, they enhance lipolysis, ketogenesis, mitochondrial biogenesis, and autophagy while they attenuate the renin-angiotensin-aldosterone system, lipogenesis, endoplasmic reticulum stress, oxidative stress, apoptosis, and fibrogenesis. This review explains the beneficial effects of SGLT-2 inhibitors on NAFLD and cardiovascular and renal diseases and dissects the underlying molecular mechanisms in detail. This narrative review explains the beneficial effects of SGLT-2 inhibitors on NAFLD and cardiovascular and renal diseases using the results of latest observational studies, clinical trials, and meta-analyses. Thereafter, it dissects the underlying molecular mechanisms involved in the clinical effects of SGLT-2 inhibitors on these diseases.
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Affiliation(s)
- Moein Ala
- School of Medicine, Tehran University of Medical Sciences (TUMS), Tehran, Iran
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Namkhah Z, Naeini F, Ostadrahimi A, Tutunchi H, Hosseinzadeh-Attar MJ. The association of the adipokine zinc-alpha2-glycoprotein with non-alcoholic fatty liver disease and related risk factors: A comprehensive systematic review. Int J Clin Pract 2021; 75:e13985. [PMID: 33404166 DOI: 10.1111/ijcp.13985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Accepted: 01/03/2021] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND AIM The adipokine zinc-alpha2-glycoprotein (ZAG), a multidisciplinary protein, is involved in lipid metabolism, glucose homeostasis and energy balance. Accumulating evidence demonstrates that the expression of ZAG is mainly downregulated in obesity and obesity-related conditions. In the present study, we assessed the association of ZAG with non-alcoholic fatty liver disease (NAFLD) and the related risk factors including obesity, metabolic factors and inflammatory parameters, with emphasis on potential mechanisms underlying these associations. METHODS PRISMA guidelines were followed in this review. Systematic searches were performed using the PubMed/Medline, ScienceDirect, Scopus, EMBASE, ProQuest and Google Scholar databases, up to August 2020 for all relevant published papers. RESULTS Out of 362 records screened, 34 articles were included in the final analysis. According to the studies reviewed here, ZAG appears to exert a protective effect against NAFLD by enhancing mRNA expression levels of peroxisome proliferator-activated receptor α (PPARα) and PPARγ, promoting mRNA expression levels of the lipolysis-related genes, reducing mRNA expression levels of the lipogenesis-related genes, increasing hepatic fatty acid oxidation, ameliorating hepatic steatosis, promoting the activity of brown adipose tissue and the expression of thermogenesis-related genes, modulating energy balance and glucose homeostasis, and elevating plasma levels of healthy adipokines such as adiponectin. ZAG can also be involved in the regulation of inflammatory responses by attenuation of the expression of pro-inflammatory and pro-fibrotic mediators. CONCLUSION According to the studies reviewed here, ZAG is suggested to be a promising therapeutic target for NAFLD. However, the favourable effects of ZAG need to be confirmed in prospective cohort studies.
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Affiliation(s)
- Zahra Namkhah
- Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Science, Tehran, Iran
| | - Fatemeh Naeini
- Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Science, Tehran, Iran
| | - Alireza Ostadrahimi
- Nutrition Research Center, Department of Clinical Nutrition, School of Nutrition & Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Helda Tutunchi
- Nutrition Research Center, Department of Clinical Nutrition, School of Nutrition & Food Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
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Banaszak M, Górna I, Przysławski J. Zinc and the Innovative Zinc-α2-Glycoprotein Adipokine Play an Important Role in Lipid Metabolism: A Critical Review. Nutrients 2021; 13:nu13062023. [PMID: 34208404 PMCID: PMC8231141 DOI: 10.3390/nu13062023] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 06/10/2021] [Accepted: 06/10/2021] [Indexed: 12/14/2022] Open
Abstract
Numerous studies indicate that zinc and the new zinc-related adipokine, zinc-α2-glycoprotein (ZAG), are involved in lipid metabolism. Excess body fat lowers blood concentrations of Zn and ZAG, leading not only to the development of obesity but also to other components of the metabolic syndrome. Zinc homeostasis disorders in the body negatively affect the lipid profile and cytokine secretion. Zinc appears to be a very important ZAG homeostasis regulator. The physiological effects of ZAG are related to lipid metabolism, but studies show that ZAG also affects glucose metabolism and is linked to insulin resistance. ZAG has a zinc binding site in its structure, which may indicate that ZAG mediates the effect of zinc on lipid metabolism. The review aimed to verify the available studies on the effects of zinc and ZAG on lipid metabolism. A literature review within the scope of this research area was conducted using articles available in PubMed (including MEDLINE), Web of Science and Cochrane Library databases. An analysis of available studies has shown that zinc improves hepatic lipid metabolism and has an impact on the lipid profile. Numerous studies have found that zinc supplementation in overweight individuals significantly reduced blood levels of total cholesterol, LDL (Low-density lipoprotein)cholesterol and triglycerides, potentially reducing cardiovascular morbidity and mortality. Some results also indicate that it increases HDL-C (High-density lipoprotein) cholesterol levels. ZAG has been shown to play a significant role in reducing obesity and improving insulin sensitivity, both in experimental animal model studies and in human studies. Furthermore, ZAG at physiologically relevant concentrations increases the release of adiponectin from human adipocytes. In addition, ZAG has been shown to inhibit in vitro leptin production. Further studies are needed to provide more data on the role of zinc and zinc-α2-glycoprotein.
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Affiliation(s)
- Michalina Banaszak
- Faculty of Medical Sciences, Poznan University of Medical Sciences, 60-812 Poznan, Poland;
| | - Ilona Górna
- Department of Bromatology, Poznan University of Medical Sciences, 60-354 Poznan, Poland;
- Correspondence: ; Tel.: +48-61-854-7204
| | - Juliusz Przysławski
- Department of Bromatology, Poznan University of Medical Sciences, 60-354 Poznan, Poland;
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Zhang W, Qiao Y, Qi F, Shen Q, Zhao R, Yang X. Zinc-α2-Glycoprotein Knockout Influenced Genes Expression Profile in Adipose Tissue and Decreased the Lipid Mobilizing After Dexamethasone Treatment in Mice. Horm Metab Res 2020; 52:755-763. [PMID: 32542628 DOI: 10.1055/a-1186-0649] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Zinc-α2-glycoprotein (ZAG), as an adipokine, plays an important role in lipid metabolism. However, its influence on whole gene expression profile in adipose tissue is not known. Under stress condition, how ZAG affects the lipid metabolism is also unclear. Therefore, in this study ZAG systemic knockout (KO) mice were used as a model to reveal the genes expression profile in visceral fat tissues of ZAG KO mice and wild-type mice by genome-wide microarray screening. Then dexamethasone (DEX) was used to explore the effect of ZAG deletion on body fat metabolism under stress. Our results showed that 179 genes were differentially expressed more than 1.5 times between ZAG KO mice and wild type mice, of which 26 genes were upregulated dramatically and 153 genes were significantly downregulated. Under DEX simulated stress, ZAG systemic knockout in vivo resulted in a markedly decrease of triglycerides (TG) and nonesterified fatty acid (NEFA) content in in plasma. Similarly, for lipid catabolism, ZAG KO led to a significant increase of phosphorylated HSL (p-HSL) protein and a rising tendency of adipose triglyceride lipase (ATGL) protein relative to those of the DEX group. For lipid anabolism, fatty acid synthase (FAS) and adiponectin protein expression in visceral fat rose notably in ZAG KO mice after DEX treatment. In conclusion, ZAG knockout can affect the gene expression profile of adipose tissue, reduce elevated TG and NEFA levels in plasma, and alter lipid metabolism under DEX treatment. These findings provide new insights into the mechanism of lipid metabolic disorders in response to stress.
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Affiliation(s)
- Wenge Zhang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing Agricultural University, Nanjing, P. R. China
| | - Yu Qiao
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing Agricultural University, Nanjing, P. R. China
| | - Fulei Qi
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing Agricultural University, Nanjing, P. R. China
| | - Qingyi Shen
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing Agricultural University, Nanjing, P. R. China
| | - Ruqian Zhao
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing Agricultural University, Nanjing, P. R. China
| | - Xiaojing Yang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing Agricultural University, Nanjing, P. R. China
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Fan G, Dang X, Li Y, Chen J, Zhao R, Yang X. Zinc-α2-glycoprotein promotes browning of white adipose tissue in cold-exposed male mice. Mol Cell Endocrinol 2020; 501:110669. [PMID: 31790716 DOI: 10.1016/j.mce.2019.110669] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 11/26/2019] [Accepted: 11/28/2019] [Indexed: 12/22/2022]
Abstract
The promotion of white adipose tissue (WAT) browning has emerged as a promising therapeutic target to increase energy expenditure and decrease weight gain. Zinc-α2-glycoprotein (ZAG) is a newly identified adipokine that regulates lipid metabolism. It shows high expression in brown adipose tissue (BAT), but whether ZAG plays a key role in the browning of white adipose tissue is still largely unclear. In the present study, we explored the relationship between ZAG and the browning of WAT in cold-exposed ZAG knockout (KO) mice and 3T3-L1 adipocytes with overexpressed ZAG. The results showed that cold stress induced marked accumulation of ZAG in wild type (WT) mice. Additionally, ZAG deficiency inhibited the loss of body weight and adipose tissue weight in cold stressed mice. ZAG KO mice were resistant to cold-induced expression of browning markers and energy metabolism in WAT. Furthermore, replenishment ZAG plasmid improved the reduction in cold-induced browning of WAT in ZAG KO mice. In vitro, ZAG overexpression promoted browning and mitochondrial biogenesis and increased the expression of β3-AR and P-P38 in 3T3-L1 adipocytes. These findings demonstrate that ZAG can promote the browning of white adipose tissue and can serve as a potential therapeutic target for treating metabolic diseases such as obesity.
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Affiliation(s)
- Guoqiang Fan
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Xiaobo Dang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Yanfei Li
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Jinglong Chen
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Ruqian Zhao
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Xiaojing Yang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing Agricultural University, Nanjing, 210095, PR China.
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Liu M, Zhang K, Wang L, Yang H, Yan K, Pan H, Zhu H, Gong F. Serum ZAG and Adiponectin Levels Were Closely Related to Obesity and the Metabolically Abnormal Phenotype in Chinese Population. Diabetes Metab Syndr Obes 2020; 13:3099-3112. [PMID: 32904655 PMCID: PMC7457588 DOI: 10.2147/dmso.s257643] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 08/03/2020] [Indexed: 12/27/2022] Open
Abstract
INTRODUCTION To explore serum zinc-α2-glycoprotein (ZAG) and adiponectin in metabolically healthy non-obese (MHNO), metabolically healthy obesity (MHO), metabolically abnormal obesity (MAO) and metabolically abnormal diabetic obese (MADO) subjects and the relationship with metabolically phenotypes of obesity. METHODS Two hundred twenty-five subjects including 32 with MHNO, 40 with MHO, 104 with MAO and 49 with MADO were enrolled. Baseline clinical data and biochemical variables were collected. Serum ZAG and adiponectin levels were measured by enzyme-linked immunosorbent assay (ELISA) kits. Metabolically healthy (<3 metabolic abnormalities) or abnormal (≥3 metabolic abnormalities) subjects were classified based on the National Cholesterol Education Program-Adult Treatment Panel III (NCEP/ATP III) criteria. Obesity (body mass index ≥28 kg/m2) was recommended by China Obesity Task Force. RESULTS Serum ZAG levels were higher in the MHO group, but were progressively lower in MAO and MADO groups (P all<0.05). In all subjects, total cholesterol, 2-hour postprandial blood glucose and homeostasis model assessment of adiponectin were independent variables to serum ZAG levels. Compared with subjects in the highest tertile of ZAG, the odds ratio (OR) of metabolically abnormal risks of subjects in the lowest and median tertiles of ZAG were higher both in a univariate and three adjustment models (P all<0.05). Serum ZAG could discriminate the metabolically abnormal phenotype with receiver operating characteristic (ROC) curve area of 0.622 (95% CI, 0.539-0.706, P<0.05). Combination of ZAG and adiponectin had improved diagnosis value accuracy, with ROC curve area of 0.703 (95% CI, 0.629-0.776, P<0.05), and 62.7% sensitivity and 73.6% specificity. CONCLUSION Serum ZAG levels were higher in MHO subjects, but lower in MAO and MADO subjects. The decreased serum ZAG levels were closely related to the metabolically abnormal phenotype of obese patients. Serum ZAG, especially the combination with adiponectin might be the potential diagnostic biomarkers for metabolically abnormal obese patients.
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Affiliation(s)
- Meijuan Liu
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing100730, People’s Republic of China
| | - Kun Zhang
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing100730, People’s Republic of China
| | - Linjie Wang
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing100730, People’s Republic of China
| | - Hongbo Yang
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing100730, People’s Republic of China
| | - Kemin Yan
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing100730, People’s Republic of China
| | - Hui Pan
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing100730, People’s Republic of China
| | - Huijuan Zhu
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing100730, People’s Republic of China
| | - Fengying Gong
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing100730, People’s Republic of China
- Correspondence: Fengying Gong; Huijuan Zhu Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, 1# Shuaifuyuan, Wangfujing, Beijing100730, People’s Republic of ChinaTel +86 10 69155100Fax +86 10 69155073 Email ;
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Wang L, Liu M, Ning D, Zhu H, Shan G, Wang D, Ping B, Yu Y, Yang H, Yan K, Pan H, Gong F. Low Serum ZAG Levels Correlate With Determinants of the Metabolic Syndrome in Chinese Subjects. Front Endocrinol (Lausanne) 2020; 11:154. [PMID: 32265843 PMCID: PMC7105689 DOI: 10.3389/fendo.2020.00154] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 03/05/2020] [Indexed: 12/11/2022] Open
Abstract
Introduction: Zinc-α2-glycoprotein (ZAG) is a novel adipokine, which is involved in metabolic syndrome (MetS). This study aimed to investigate the relationship between serum ZAG and MetS in Chinese adults, who diagnosed according to the 2005 International Diabetes Federation (IDF) criteria. Methods: A group of 151 MetS patients, 84 patients with central obesity and 70 healthy controls were enrolled. General clinical information, serum samples were obtained from all subjects and serum ZAG levels were determined via the commercial ELISA kits. Results: Serum ZAG levels were the highest in the control group, then gradually decreased with the severity of the metabolic abnormalities increased (8.78 ± 1.66 μg/mL for control vs. 8.37 ± 1.52 μg/mL for central obesity vs. 7.98 ± 0.94 μg/mL for MetS, P < 0.05). It was also decreased progressively with an increasing number of the MetS components (P for trend = 0.002). Additionally, serum ZAG/fat mass ratio was calculated and the similar changes were observed in the three groups (0.85 ± 0.53 μg/mL/kg for control vs. 0.39 ± 0.10 μg/mL/kg for central obesity vs. 0.36 ± 0.08 μg/mL/kg for MetS, P < 0.05). In the multiple regression analysis, group was a strong independent factor contributing to serum ZAG levels (P < 0.001). Furthermore, compared with subjects with the highest tertile of ZAG, subjects in the lowest tertile of ZAG had 1.946-fold higher risk of MetS (95% CI 1.419-6.117, P = 0.004). This phenomenon still existed after controlling for age, gender (Model 1), ALP, AST, Cr, UA, Urea based on Model 1 (Model 2), grip strength, smoking, drinking, birth place, current address, education level, manual labor, and exercise frequency based on Model 2 (Model 3). Receiver operation characteristic (ROC) curve analysis revealed that serum ZAG might serve as a candidate biomarker for MetS (sensitivity 57.6%, specificity 70.0% and area under the curve 0.655), and serum ZAG/fat mass ratio showed improved diagnosis value accuracy, with ROC curve area of 0.951 (95% CI, 0.920-0.983, P < 0.001), and 90.7% sensitivity and 88.6% specificity. Conclusions: Serum ZAG levels were lowered in patients with MetS and central obesity. The decreased serum ZAG levels were associated with the increased risks of MetS. Serum ZAG, especially serum ZAG/fat mass ratio might be the candidate diagnostic biomarkers for MetS.
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Affiliation(s)
- Linjie Wang
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Meijuan Liu
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Dongping Ning
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Huijuan Zhu
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Guangliang Shan
- Department of Epidemiology and Health Statistics, Institute of Basic Medical Sciences, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Dingming Wang
- Guizhou Provincial Center for Disease Control and Prevention, Guiyang, China
| | - Bo Ping
- Longli Center for Disease Control and Prevention, Longli, China
| | - Yangwen Yu
- Guizhou Provincial Center for Disease Control and Prevention, Guiyang, China
| | - Hongbo Yang
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Kemin Yan
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Hui Pan
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
- *Correspondence: Hui Pan
| | - Fengying Gong
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
- Fengying Gong ;
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Liu T, Luo X, Li ZH, Wu JC, Luo SZ, Xu MY. Zinc-α2-glycoprotein 1 attenuates non-alcoholic fatty liver disease by negatively regulating tumour necrosis factor-α. World J Gastroenterol 2019; 25:5451-5468. [PMID: 31576092 PMCID: PMC6767980 DOI: 10.3748/wjg.v25.i36.5451] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 07/26/2019] [Accepted: 08/24/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Zinc-α2-glycoprotein 1 (AZGP1) plays important roles in metabolism-related diseases. The underlying molecular mechanisms and therapeutic effects of AZGP1 remain unknown in non-alcoholic fatty liver disease (NAFLD).
AIM To explore the effects and potential mechanism of AZGP1 on NAFLD in vivo and in vitro.
METHODS The expression of AZGP1 and its effects on hepatocytes were examined in NAFLD patients, CCl4-treated mice fed a high fat diet (HFD), and human LO2 cells.
RESULTS AZGP1 levels were significantly decreased in liver tissues of NAFLD patients and mice. AZGP1 knockdown was found to activate inflammation; enhance steatogenesis, including promoting lipogenesis [sterol regulatory element-binding protein (SREBP)-1c, liver X receptor (LXR), fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC), and stearoyl CoA desaturase 1 (SCD)-1], increasing lipid transport and accumulation [fatty acid transport protein (FATP), carnitine palmitoyl transferase (CPT)-1A, and adiponectin], and reducing fatty acid β-oxidation [farnesoid X receptor (FXR) and peroxisome proliferator-activated receptor (PPAR)-α]; accelerate proliferation; and reverse apoptosis in LO2 cells. AZGP1 overexpression (OV-AZGP1) had the opposite effects. Furthermore, AZGP1 alleviated NAFLD by blocking TNF-α-mediated inflammation and intracellular lipid deposition, promoting proliferation, and inhibiting apoptosis in LO2 cells. Finally, treatment with OV-AZGP1 plasmid dramatically improved liver injury and eliminated liver fat in NAFLD mice.
CONCLUSION AZGP1 attenuates NAFLD with regard to ameliorating inflammation, accelerating lipolysis, promoting proliferation, and reducing apoptosis by negatively regulating TNF-α. AZGP1 is suggested to be a novel promising therapeutic target for NAFLD.
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Affiliation(s)
- Ting Liu
- Department of Gastroenterology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China
- Department of Gastroenterology, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, Hebei Province, China
- Shanghai Key Laboratory of Pancreatic Diseases, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China
| | - Xin Luo
- Department of Gastroenterology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China
- Shanghai Key Laboratory of Pancreatic Diseases, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China
| | - Zheng-Hong Li
- Department of Gastroenterology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China
| | - Jun-Cheng Wu
- Department of Gastroenterology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China
- Shanghai Key Laboratory of Pancreatic Diseases, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China
| | - Sheng-Zheng Luo
- Department of Gastroenterology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China
| | - Ming-Yi Xu
- Department of Gastroenterology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China
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Effect of prenatal zinc supplementation on adipose tissue-derived hormones and neonatal weight, height and head circumference in women with impaired glucose tolerance test: randomized clinical controlled trial. Int J Diabetes Dev Ctries 2019. [DOI: 10.1007/s13410-018-0707-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
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Gao SX, Guo J, Fan GQ, Qiao Y, Zhao RQ, Yang XJ. ZAG alleviates HFD-induced insulin resistance accompanied with decreased lipid depot in skeletal muscle in mice. J Lipid Res 2018; 59:2277-2286. [PMID: 30318474 PMCID: PMC6277152 DOI: 10.1194/jlr.m082180] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 09/24/2018] [Indexed: 12/25/2022] Open
Abstract
Over the past two decades, intramuscular lipids have been viewed as a cause of insulin resistance due to their ability to suppress insulin-stimulated glucose uptake in skeletal muscle. Zinc-α2-glycoprotein (ZAG) is an adipokine involved in lipolysis of white adipose tissue (WAT). To investigate the action of ZAG on insulin resistance induced by a high-fat diet (HFD), which affects the intramuscular fat, mice were divided into three groups, normal diet, HFD, and ZAG treatment under HFD (HFZ). The results showed that the insulin sensitivity of ZAG-treated mice was significantly improved. The body weight, WAT weight, and intramuscular fat were significantly decreased in the HFZ group compared with the HFD group. The lipolytic enzymes, including phosphorylation of hormone-sensitive lipase and adipose triglyceride lipase, were significantly upregulated in the skeletal muscle of mice that received the ZAG treatment compared with the HFD group. Insulin signaling proteins, such as phosphorylation of insulin receptor substrate 1 and cell membrane glucose transporter type 4, were also significantly increased in the skeletal muscle of the ZAG-treated group. Furthermore, a metabolic rate study showed that ZAG overexpression increases the respiratory exchange ratio and heat production. In vitro, ZAG treatment promotes glucose uptake and decreases intracellular lipids in C2C12 myotubes. Taken together, these data showed that overexpression of ZAG alleviates HFD-induced insulin resistance in mice, along with decreasing the lipid content of skeletal muscle.
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Affiliation(s)
- Shi-Xing Gao
- Key Laboratory of Animal Physiology and Biochemistry, Nanjing Agricultural University, Nanjing 210095, People's Republic of China
| | - Jun Guo
- Key Laboratory of Animal Physiology and Biochemistry, Nanjing Agricultural University, Nanjing 210095, People's Republic of China
| | - Guo-Qiang Fan
- Key Laboratory of Animal Physiology and Biochemistry, Nanjing Agricultural University, Nanjing 210095, People's Republic of China
| | - Yu Qiao
- Key Laboratory of Animal Physiology and Biochemistry, Nanjing Agricultural University, Nanjing 210095, People's Republic of China
| | - Ru-Qian Zhao
- Key Laboratory of Animal Physiology and Biochemistry, Nanjing Agricultural University, Nanjing 210095, People's Republic of China
| | - Xiao-Jing Yang
- Key Laboratory of Animal Physiology and Biochemistry, Nanjing Agricultural University, Nanjing 210095, People's Republic of China
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12
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Qiao Y, Fan G, Guo J, Gao S, Zhao R, Yang X. Effects of adipokine zinc-α2-glycoprotein on adipose tissue metabolism after dexamethasone treatment. Appl Physiol Nutr Metab 2018; 44:83-89. [PMID: 29972738 DOI: 10.1139/apnm-2018-0165] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Zinc-α2-glycoprotein (ZAG) has been demonstrated to play a role in stimulating lipid mobilization under normal conditions. However, further studies are required to determine whether ZAG overexpression can alleviate the reduction in plasma lipid levels under stress conditions. In the present study, we investigated the effects of ZAG on lipometabolism in white adipose tissue (WAT) after dexamethasone (DEX) stimulation using C57BL/6 male mice as the experimental models. Transcript and protein levels of genes associated with the β-adrenoreceptor (β-AR)/cyclic adenosine monophosphate/protein kinase a (PKA) pathway, lipid mobilization, and energy metabolism were determined by quantitative real-time polymerase chain reaction and Western blotting. Plasma levels of nonesterified fatty acid (NEFA) were measured using an automatic biochemical analyzer. Results indicated that plasma NEFA levels were decreased in the DEX group, but NEFA levels were rescued by ZAG overexpression. ZAG overexpression resulted in the upregulation of β3-AR and phosphorylated PKA protein relative to those of the DEX group. Analysis of lipometabolism showed that protein levels of phosphorylated hormone-sensitive lipase was reduced upon DEX treatment but were restored by ZAG overexpression. For energy metabolism, ZAG significantly upregulated the protein expression of carnitine palmitoyltransferase1a and cytochrome c oxidase subunit 1 relative to those of the DEX group. In conclusion, ZAG could alleviate DEX-induced decrease in plasma NEFA levels and this could be associated with the promoting lipid mobilization in WAT.
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Affiliation(s)
- Yu Qiao
- Key Laboratory of Animal Physiology & Biochemistry, Nanjing Agricultural University, Nanjing 210095, P.R. China.,Key Laboratory of Animal Physiology & Biochemistry, Nanjing Agricultural University, Nanjing 210095, P.R. China
| | - Guoqiang Fan
- Key Laboratory of Animal Physiology & Biochemistry, Nanjing Agricultural University, Nanjing 210095, P.R. China.,Key Laboratory of Animal Physiology & Biochemistry, Nanjing Agricultural University, Nanjing 210095, P.R. China
| | - Jun Guo
- Key Laboratory of Animal Physiology & Biochemistry, Nanjing Agricultural University, Nanjing 210095, P.R. China.,Key Laboratory of Animal Physiology & Biochemistry, Nanjing Agricultural University, Nanjing 210095, P.R. China
| | - Shixing Gao
- Key Laboratory of Animal Physiology & Biochemistry, Nanjing Agricultural University, Nanjing 210095, P.R. China.,Key Laboratory of Animal Physiology & Biochemistry, Nanjing Agricultural University, Nanjing 210095, P.R. China
| | - Ruqian Zhao
- Key Laboratory of Animal Physiology & Biochemistry, Nanjing Agricultural University, Nanjing 210095, P.R. China.,Key Laboratory of Animal Physiology & Biochemistry, Nanjing Agricultural University, Nanjing 210095, P.R. China
| | - Xiaojing Yang
- Key Laboratory of Animal Physiology & Biochemistry, Nanjing Agricultural University, Nanjing 210095, P.R. China.,Key Laboratory of Animal Physiology & Biochemistry, Nanjing Agricultural University, Nanjing 210095, P.R. China
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13
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Euclydes VLV, Castro NP, Lima LR, Brito C, Ribeiro L, Simões FA, Requena G, Luzia LA, Rondó PH. Cord blood concentrations of leptin, zinc-α2-glycoprotein, and adiponectin, and adiposity gain during the first 3 mo of life. Nutrition 2018; 54:89-93. [PMID: 29758496 DOI: 10.1016/j.nut.2018.02.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 12/21/2017] [Accepted: 02/06/2018] [Indexed: 01/02/2023]
Abstract
OBJECTIVES Adipose tissue development starts in intrauterine life and cytokines are involved in this process. Therefore, understanding the role of cytokines in the fat mass gain of infants is crucial to prevent obesity later in life. Furthermore, recent evidence indicates a sex-specific link between cytokines and adipose tissue development. The objective of this study was to assess sex-specific relationships of cord blood concentrations of the cytokines leptin, zinc-α2-glycoprotein (ZAG), and adiponectin with infant adiposity during the first 3 mo of life. METHODS This was a prospective cohort study of 104 mother-infant pairs that were selected from a maternity hospital in Sao Paulo, Brazil. Cord blood leptin, ZAG, and adiponectin were determined by enzyme-linked immunosorbent assays. The body composition of the infants was assessed monthly by air displacement plethysmography. A multiple linear regression analysis was conducted with the average fat mass gain from birth to the third month of life as the outcome and cord blood leptin, ZAG, and adiponectin as the variables of interest. RESULTS Leptin was inversely associated with fat mass gain in the first 3 mo of life (P = 0.003; adjusted R2 = 0.09). There were inverse associations of leptin (P = 0.021), ZAG (P = 0.042), and maternal body mass index (P = 0.04) with fat mass gain in girls (adjusted R2 = 0.29) but fat mass gain in boys was positively associated with gestational age (P = 0.01; adjusted R2 = 0.15). CONCLUSIONS The results of this study suggest that adiposity programming is sex-specific, which highlights the need to investigate the different metabolic mechanisms that are involved in adipogenesis.
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Affiliation(s)
- Verônica L V Euclydes
- Postgraduate Program in Applied Human Nutrition, University of Sao Paulo, Sao Paulo, Brazil
| | - Natalia P Castro
- Department of Nutrition, School of Public Health, University of Sao Paulo, Sao Paulo, Brazil
| | - Lourdes R Lima
- Laboratory of Immunology, Adolfo Lutz Institute, Sao Paulo, Brazil
| | - Cyro Brito
- Laboratory of Immunology, Adolfo Lutz Institute, Sao Paulo, Brazil
| | - Laisa Ribeiro
- Department of Nutrition, School of Public Health, University of Sao Paulo, Sao Paulo, Brazil
| | - Fernanda Agapito Simões
- Department of Nutrition, School of Public Health, University of Sao Paulo, Sao Paulo, Brazil
| | - Guaraci Requena
- Institute of Mathematics and Statistics, University of Sao Paulo, Sao Paulo, Brazil
| | - Liania Alves Luzia
- Department of Nutrition, School of Public Health, University of Sao Paulo, Sao Paulo, Brazil
| | - Patricia Helen Rondó
- Postgraduate Program in Applied Human Nutrition, University of Sao Paulo, Sao Paulo, Brazil; Department of Nutrition, School of Public Health, University of Sao Paulo, Sao Paulo, Brazil.
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14
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Liu M, Zhu H, Dai Y, Pan H, Li N, Wang L, Yang H, Yan K, Gong F. Zinc-α2-Glycoprotein Is Associated with Obesity in Chinese People and HFD-Induced Obese Mice. Front Physiol 2018; 9:62. [PMID: 29467670 PMCID: PMC5808341 DOI: 10.3389/fphys.2018.00062] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 01/18/2018] [Indexed: 12/14/2022] Open
Abstract
Zinc-α2-glycoprotein (ZAG) plays an important role in the regulation of body weight, body fat, and glucose metabolism. In this study, we first measured ZAG levels in serum and ZAG mRNA levels in subcutaneous white adipose tissue (sWAT) among overweight/obese patients and lean control subjects. Second, we investigated the effects of ZAG administration on the body weight, body fat and glucose metabolism of high-fat diet (HFD)-induced obese ICR mice and the possible mechanisms involved. The results showed that serum ZAG and mRNA levels in sWAT were significantly decreased in overweight/obese patients and that both showed a negative association with body mass index (BMI) and body weight after adjustment for age and sex. Further partial correlation analysis found that ZAG mRNA expression was positively related with several WAT browning-related genes, including uncoupling protein 1 (UCP1) (r = 0.67) and peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC1a) (r = 0.60), in the sWAT of all subjects. Additionally, intraperitoneal injection of a ZAG expression plasmid (5 μg/injection, four times a week) in HFD-induced obese mice for 8 weeks demonstrated that ZAG overexpression significantly decreased body weight and WAT mass, and greatly increased the glucose tolerance of obese mice, as shown by the intraperitoneal glucose tolerance test (IPGTT) and intraperitoneal insulin tolerance test (IPITT). The staining of UCP1-positive adipocytes was significantly stronger in the sWAT of ZAG-treated obese mice than in that of obese control mice. The mRNA and protein levels of PGC1α in sWAT were significantly increased to 2.2- and 5.3-fold, respectively, compared with HFD obese mice, and there was a strong positive correlation between the expression levels of Zag and Pgc1α in mouse sWAT (r = 0.74). A similar phenomenon was also observed in visceral white adipose tissue (vWAT): the mRNA and protein levels of PGC1α were increased to 1.9- and 3.6-fold, respectively, when obese mice were treated with ZAG. In conclusion, ZAG levels in both sWAT and serum are inversely related with BMI and body weight in Chinese subjects. The action of ZAG on body weight, fat mass and glucose metabolism may be realized through activating PGC1α expression in sWAT and vWAT, then promoting WAT browning in obese mice.
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Affiliation(s)
- Meijuan Liu
- Key Laboratory of Endocrinology of National Health and Family Planning Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Huijuan Zhu
- Key Laboratory of Endocrinology of National Health and Family Planning Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Yufei Dai
- Key Laboratory of Endocrinology of National Health and Family Planning Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Hui Pan
- Key Laboratory of Endocrinology of National Health and Family Planning Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Naishi Li
- Key Laboratory of Endocrinology of National Health and Family Planning Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Linjie Wang
- Key Laboratory of Endocrinology of National Health and Family Planning Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Hongbo Yang
- Key Laboratory of Endocrinology of National Health and Family Planning Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Kemin Yan
- Key Laboratory of Endocrinology of National Health and Family Planning Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Fengying Gong
- Key Laboratory of Endocrinology of National Health and Family Planning Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
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15
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Xiao XH, Qi XY, Wang YD, Ran L, Yang J, Zhang HL, Xu CX, Wen GB, Liu JH. Zinc alpha2 glycoprotein promotes browning in adipocytes. Biochem Biophys Res Commun 2018; 496:287-293. [DOI: 10.1016/j.bbrc.2018.01.039] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Accepted: 01/05/2018] [Indexed: 02/06/2023]
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16
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Hosseinzadeh-Attar MJ, Mahdavi-Mazdeh M, Yaseri M, Zahed NS, Alipoor E. Comparative Assessment of Serum Adipokines Zinc-α2-glycoprotein and Adipose Triglyceride Lipase, and Cardiovascular Risk Factors Between Normal Weight and Obese Patients with Hemodialysis. Arch Med Res 2017; 48:459-466. [PMID: 29128140 DOI: 10.1016/j.arcmed.2017.10.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2017] [Accepted: 10/17/2017] [Indexed: 12/25/2022]
Abstract
BACKGROUND Little is known about the potential relationship of obesity, adipose tissue and novel adipokines with cardiometabolic risk factors in end-stage renal disease. Zinc-α2-glycoprotein (ZAG) and adipose triglyceride lipase (ATGL) are novel adipokines with proposed desirable effects on inflammation, and lipid and glucose metabolism. The aim of this study was to investigate serum concentrations of ZAG and ATGL, and the relationship of these adipokines with cardiovascular risk factors in normal weight (NW) and obese (OB) patients undergoing hemodialysis. METHODS Patients with regular hemodialysis including 44 normal weight (18.5<BMI<25 kg/m2) and 44 obese (BMI≥30 kg/m2) were enrolled. Serum lipid profile, high-sensitivity C-reactive protein (hsCRP) and nitric oxide metabolites along with ZAG and ATGL concentrations were assessed. RESULTS ZAG concentrations were significantly lower in OB compared to NW group (100 ± 34 vs. 106 ± 31 ng/ml; p = 0.007). No significant difference was observed in ATGL between the two groups. A significant inverse correlation between ZAG and HDL (r = ‒0.236, p = 0.048) and a marginal inverse correlation between ATGL and HDL (r = ‒0.211, p = 0.078) were observed in all patients. ZAG had positive correlations with triglyceride/HDL (r = 0.279, p = 0.019), cholesterol/HDL (r = 0.319, p = 0.007), and LDL/HDL (r = 0.26, p = 0.029) ratios. Among cardiovascular risk factors, only LDL/HDL ratio and hsCRP were significantly higher in OB patients (p = 0.009 and p = 0.038, respectively). CONCLUSIONS Serum concentrations of ZAG, but not ATGL, were significantly lower in the OB group. It appears that obesity overrides the role of hemodialysis in determining ZAG concentration. In contrast, uremic condition might overshadow the role of obesity in determining levels of traditional cardiovascular risk factors.
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Affiliation(s)
- Mohammad Javad Hosseinzadeh-Attar
- Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran; Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
| | - Mitra Mahdavi-Mazdeh
- Iranian Tissue Bank and Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Mehdi Yaseri
- Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Narges Sadat Zahed
- Department of Nephrology, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Elham Alipoor
- Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran.
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17
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Zinc status is associated with inflammation, oxidative stress, lipid, and glucose metabolism. J Physiol Sci 2017; 68:19-31. [PMID: 28965330 PMCID: PMC5754376 DOI: 10.1007/s12576-017-0571-7] [Citation(s) in RCA: 278] [Impact Index Per Article: 39.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 09/18/2017] [Indexed: 12/14/2022]
Abstract
A number of studies have reported that zinc plays a substantial role in the development of metabolic syndrome, taking part in the regulation of cytokine expression, suppressing inflammation, and is also required to activate antioxidant enzymes that scavenge reactive oxygen species, reducing oxidative stress. Zinc also plays a role in the correct functioning of lipid and glucose metabolism, regulating and forming the expression of insulin. In numerous studies, zinc supplementation has been found to improve blood pressure, glucose, and LDL cholesterol serum level. Deeper knowledge of zinc’s properties may help in treating metabolic syndrome, thus protecting against stroke and angina pectoris, and ultimately against death.
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18
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Alipoor E, Esmaillzadeh A, Mahdavi-Mazdeh M, Yaseri M, Zahed NS, Hosseinzadeh-Attar MJ. The relationship of serum adipokines with malnutrition inflammation score in haemodialysis. Eur J Clin Invest 2017. [PMID: 28621798 DOI: 10.1111/eci.12774] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND Protein-energy wasting is a prevalent disorder in haemodialysis. Zinc-α2-glycoprotein (ZAG) and adipose triglyceride lipase (ATGL) are novel adipokines with recognized lipolytic effects and proposed role in metabolic homoeostasis. This study was conducted to investigate the association of ZAG and ATGL concentrations with malnutrition-inflammation score (MIS) and metabolic profile of patients with haemodialysis. MATERIALS AND METHODS Eighty-eight patients under regular haemodialysis were divided based on MIS to normal to mild wasting (NMW; n = 35) or moderate wasting (MW; n = 53) group. Anthropometric measurements along with fasting serum concentrations of ZAG, ATGL, free fatty acids (FFAs), albumin, transferrin, total iron-binding capacity (TIBC), hs-CRP, lipid profile and glucose metabolism were assessed. RESULTS Adipose triglyceride lipase concentration was significantly higher in MW than NMW group (10·89 ± 5·7 vs. 8·02 ± 3·37 mIU/mL; P = 0·008). The ZAG and FFAs were not significantly different between two groups. ATGL was directly correlated with FFAs in all of the patients (r = 0·284, P = 0·007) and MW (r = 0·32, P = 0·021), and marginally in NMW (r = 0·31, P = 0·057) groups. ATGL and odds of having mild or moderate wasting were significantly correlated (OR = 1·21, P = 0·033). A positive association was observed between ATGL with TG (r = 0·31, P = 0·049) and also with transferrin and TIBC (r = 0·44, P = 0·001) only in MW group. An inverse relationship was observed between ATGL and HDL in all of the participants (r=-0·222, P = 0·04). No significant correlation was observed between ZAG and other parameters. CONCLUSIONS The serum concentrations of ATGL, but not ZAG, were significantly higher in MW compared to NMW group. Each unit increase in ATGL concentrations was correlated with 21% increase in the odds of wasting severity. ATGL might play a role in wasting pathogenesis and metabolic profile in haemodialysis.
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Affiliation(s)
- Elham Alipoor
- Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran
| | - Ahmad Esmaillzadeh
- Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran
| | - Mitra Mahdavi-Mazdeh
- Iranian Tissue Bank & Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Mehdi Yaseri
- Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Narges Sadat Zahed
- Department of Nephrology, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Javad Hosseinzadeh-Attar
- Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran.,Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia
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19
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Morse KW, Astbury NM, Walczyszyn A, Hashim SA, Geliebter A. Changes in zinc-α2-glycoprotein (ZAG) plasma concentrations pre and post Roux-En-Y gastric bypass surgery (RYGB) or a very low calorie (VLCD) diet in clinically severe obese patients: Preliminary Study. ACTA ACUST UNITED AC 2017; 3. [PMID: 29367881 PMCID: PMC5777576 DOI: 10.15761/iod.1000170] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The purpose of this preliminary study was to investigate changes in plasma concentrations of zinc-α2-glycoprotein (ZAG), a lipid mobilizing hormone, in obese subjects following Roux-En-Y Gastric Bypass (RYGB) surgery or a very low calorie diet (VLCD). Fasting blood concentrations and anthropometric measurements were measured pre and 12 weeks post intervention. 14 healthy, obese individuals underwent either RYGB (N=6) surgery or a VLCD (N=8). Body composition and fasting plasma ZAG concentrations were measured at baseline (pre) and 12 weeks post intervention (post). At pre-intervention baseline, there was no difference in plasma ZAG between the two intervention groups. Post-intervention, there was a significant overall reduction (F(1,11) = 32.8, p<0.001) in plasma ZAG, which was significant only within the RYGB group from pre to post intervention (33.2 ± 5.7 μg/ml to 26.7 ± 4.8 μg/ml (p<0.015)) and significantly greater than the change within the VLCD group. The change in ZAG was inversely correlated across groups with BMI reduction (r= −0.60, p<0.05), % body fat reduction (r= −0.68, p<0.015), reduction in weight (r= −0.58, p<0.05), and % weight loss (r= −0.70, p<0.05). Overall, subjects who underwent RYGB or VLCD had a significant reduction in plasma ZAG. This reduction was significant within the RYGB group alone, who lost a larger amount of weight than the VLCD group, which suggests that ZAG may have a protective effect during marked weight loss.
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Affiliation(s)
- Kyle W Morse
- Weill Cornell Medical College, New York, NY, USA
| | | | | | | | - Allan Geliebter
- Weill Cornell Medical College, New York, NY, USA.,Department of Psychiatry, Mt Sinai St. Luke's Hospital, New York, NY, USA
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20
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Xiao X, Li H, Qi X, Wang Y, Xu C, Liu G, Wen G, Liu J. Zinc alpha2 glycoprotein alleviates palmitic acid-induced intracellular lipid accumulation in hepatocytes. Mol Cell Endocrinol 2017; 439:155-164. [PMID: 27264075 DOI: 10.1016/j.mce.2016.06.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 05/14/2016] [Accepted: 06/02/2016] [Indexed: 12/17/2022]
Abstract
Zinc alpha2 glycoprotein (ZAG) plays an important role in stimulating fat mobilization and lipolysis in adipose tissue, but its role in hepatic lipid metabolism remains unclear. Palmitic acid (PA) was used to stimulate HepG2 cells with ZAG overexpression or ZAG knock down (shRNA). Overexpression of ZAG significantly inhibited lipogenesis, promoted lipolysis and fatty acid β-oxidation, and attenuated PA-induced intracellular fat accumulation. Moreover, ZAG overexpression dramatically stimulated adiponectin expression in HepG2 cells. In contrast, knockdown of ZAG notably inhibited fatty acid β-oxidation, increased lipogenesis and lipid accumulation. Collectively, these data suggest that ZAG has the potential to alleviate hepatosteatosis, making it a promising therapeutic target for fatty liver.
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Affiliation(s)
- Xinhua Xiao
- Department of Metabolism and Endocrinology, The First Affiliated Hospital of University of South China, 421001, People's Republic of China
| | - Han Li
- Department of Metabolism and Endocrinology, The First Affiliated Hospital of University of South China, 421001, People's Republic of China
| | - Xiaoyan Qi
- Department of Metabolism and Endocrinology, The First Affiliated Hospital of University of South China, 421001, People's Republic of China
| | - Yadi Wang
- Department of Metabolism and Endocrinology, The First Affiliated Hospital of University of South China, 421001, People's Republic of China
| | - Canxin Xu
- Department of Pathology & Immunology, Developmental, Regenerative and Stem Cell Biology, Washington University in St. Louis, MO, 63110, United States
| | - Gexin Liu
- Department of Metabolism and Endocrinology, The First Affiliated Hospital of University of South China, 421001, People's Republic of China
| | - Gebo Wen
- Department of Metabolism and Endocrinology, The First Affiliated Hospital of University of South China, 421001, People's Republic of China
| | - Jianghua Liu
- Department of Metabolism and Endocrinology, The First Affiliated Hospital of University of South China, 421001, People's Republic of China.
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21
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Xu L, Yu W, Niu M, Zheng C, Qu B, Li Y, Wang J, Huang P, Wang O, Gong F. Serum ZAG Levels Were Associated with eGFR Mild Decrease in T2DM Patients with Diabetic Nephropathy. Int J Endocrinol 2017; 2017:5372625. [PMID: 28352283 PMCID: PMC5352973 DOI: 10.1155/2017/5372625] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Revised: 12/07/2016] [Accepted: 12/26/2016] [Indexed: 12/26/2022] Open
Abstract
Objective. To investigate the changes of serum zinc-α2-glycoprotein (ZAG) in type 2 diabetes mellitus (T2DM) with eGFR mild decrease. Subjects and Methods. A total of 438 T2DM patients (61.3 ± 4.0 y) were recruited and the demographic, anthropometric, and biochemical parameters were all collected. Serum ZAG levels were determined by commercially available ELISA kits. Results. The proportion of T2DM patients with the high tertile ZAG levels was 11.9% higher in patients with mildly decreased estimated glomerular filtration rate (eGFR) (<90 mL/min/1.73 m2) than those with the low tertile ZAG levels (P = 0.038). The probability of the eGFR < 90 mL/min/1.73 m2 in patients with the high ZAG levels was 94% higher than those with the low serum ZAG levels after adjusting for age, gender, and education [OR = 1.94, 95% CI (1.17-3.23), P = 0.0094]. This phenomenon was more likely to be observed in the condition of uACR ≥ 2.7 mg/mmol, WC ≥ 90 cm for men, or WC ≥ 85 cm for women. Conclusion. Serum ZAG levels were firstly found to be related with eGFR in T2DM patients. The patients with the high tertile ZAG levels were more likely to have mildly eGFR decrease, especially for female patients with higher uACR and bigger WC.
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Affiliation(s)
- Lingling Xu
- Key Laboratory of Endocrinology of National Health and Family Planning Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100730, China
| | - Weihong Yu
- Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100730, China
| | - Meng Niu
- Department of Endocrinology, Traditional Chinese Medicine Hospital of Muping District of Yantai City, Yantai, Shandong, China
| | - Caixia Zheng
- Department of Ophthalmology, Traditional Chinese Medicine Hospital of Muping District of Yantai City, Yantai, Shandong, China
| | - Bin Qu
- Department of Ophthalmology, Traditional Chinese Medicine Hospital of Muping District of Yantai City, Yantai, Shandong, China
| | - Yan Li
- Department of Ophthalmology, Traditional Chinese Medicine Hospital of Muping District of Yantai City, Yantai, Shandong, China
| | - Jing Wang
- Department of Ophthalmology, Traditional Chinese Medicine Hospital of Muping District of Yantai City, Yantai, Shandong, China
| | - Ping Huang
- Department of Ophthalmology, Traditional Chinese Medicine Hospital of Muping District of Yantai City, Yantai, Shandong, China
| | - O. Wang
- Key Laboratory of Endocrinology of National Health and Family Planning Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100730, China
| | - Fengying Gong
- Key Laboratory of Endocrinology of National Health and Family Planning Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100730, China
- *Fengying Gong:
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Sodium-Glucose Cotransporter 2 (SGLT2) Inhibitor Increases Circulating Zinc-Α2-Glycoprotein Levels in Patients with Type 2 Diabetes. Sci Rep 2016; 6:32887. [PMID: 27611858 PMCID: PMC5017191 DOI: 10.1038/srep32887] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 08/16/2016] [Indexed: 01/10/2023] Open
Abstract
ZAG has recently been characterized as a potent metabolic regulator, but the effect of anti-diabetic agents on ZAG in humans remains unknown. Our aim was to study the effects of SGLT2 inhibitor on circulating ZAG and ADI in nT2DM. 162 subjects with nT2DM were treated by a placebo or DAPA. After 3-months of DAPA therapy, HbA1c, FBG, 2h-PBG, FFA, TG, blood pressure, BMI, WHR, body weight, FAT%, FINS, and HOMA-IR in T2DM patients decreased significantly, whereas HDL-C was significantly increased. Importantly, circulating ZAG and ADI levels in these patients were also significantly increased after DAPA therapy. Basal ZAG levels were associated with changes in BMI, FAT%, TC, HbA1c, HDL-C and ADI at post-treatment, whereas basal ADI levels were associated with changes in FAT%, TC, HbA1c, FFA and HDL-c. In vitro, DAPA treatment showed increased ZAG expression and secretion in HepG2 cells. When combined with a PPAR-γinhibitor GW9662, the effect of DAPA on ZAG was abrogated. These findings suggest that circulating ZAG can be regulated by DAPA, and DAPA promotes the expression and secretion of ZAG in the liver via the activation of PPAR-γ. The changes in ZAG induced by DAPA may play a physiologic role in enhancing insulin sensitivity.
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The natural logarithm of zinc-α2-glycoprotein/HOMA-IR is a better predictor of insulin sensitivity than the product of triglycerides and glucose and the other lipid ratios. Cytokine 2016; 79:96-102. [DOI: 10.1016/j.cyto.2015.12.024] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 11/22/2015] [Accepted: 12/29/2015] [Indexed: 12/28/2022]
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Balaž M, Ukropcova B, Kurdiova T, Vlcek M, Surova M, Krumpolec P, Vanuga P, Gašperíková D, Klimeš I, Payer J, Wolfrum C, Ukropec J. Improved adipose tissue metabolism after 5-year growth hormone replacement therapy in growth hormone deficient adults: The role of zinc-α2-glycoprotein. Adipocyte 2015; 4:113-22. [PMID: 26167410 DOI: 10.4161/21623945.2014.973772] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 09/14/2014] [Accepted: 10/02/2014] [Indexed: 01/17/2023] Open
Abstract
Growth hormone (GH) supplementation therapy to adults with GH deficiency has beneficial effects on adipose tissue lipid metabolism, improving thus adipocyte functional morphology and insulin sensitivity. However, molecular nature of these effects remains unclear. We therefore tested the hypothesis that lipid-mobilizing adipokine zinc-α2-glycoprotein is causally linked to GH effects on adipose tissue lipid metabolism. Seventeen patients with severe GH deficiency examined before and after the 5-year GH replacement therapy were compared with age-, gender- and BMI-matched healthy controls. Euglycemic hyperinsulinemic clamp was used to assess whole-body and adipose tissue-specific insulin sensitivity. Glucose tolerance was determined by oGTT, visceral and subcutaneous abdominal adiposity by MRI, adipocyte size morphometrically after collagenase digestion, lipid accumulation and release was studied in differentiated human primary adipocytes in association with GH treatment and zinc-α2-glycoprotein gene silencing. Five-year GH replacement therapy improved glucose tolerance, adipose tissue insulin sensitivity and reduced adipocyte size without affecting adiposity and whole-body insulin sensitivity. Adipose tissue zinc-α2-glycoprotein expression was positively associated with whole-body and adipose tissue insulin sensitivity and negatively with adipocyte size. GH treatment to adipocytes in vitro increased zinc-α2-glycoprotein expression (>50%) and was paralleled by enhanced lipolysis and decreased triglyceride accumulation (>35%). Moreover, GH treatment improved antilipolytic action of insulin in cultured adipocytes. Most importantly, silencing zinc-α2-glycoprotein eliminated all of the GH effects on adipocyte lipid metabolism. Effects of 5-year GH supplementation therapy on adipose tissue lipid metabolism and insulin sensitivity are associated with zinc-α2-glycoprotein. Presence of this adipokine is required for the GH action on adipocyte lipid metabolism in vitro.
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Key Words
- ACC1, acetyl-CoA carboxylase 1
- BSA, bovine serum albumin
- DGAT, diacylglycerol acyltransferase
- DMEM, Dulbecco's Modified Eagle Medium
- EHC, euglycemic hyperinsulinemic clamp
- FABP4, fatty acid binding protein 4
- FAS, fatty acid synthase
- FBS, fetal bovine serum
- FFA, free fatty acids
- GAPDH, glyceraldehyde-3-phosphate dehydrogenase
- GH, growth hormone
- GHD, growth hormone deficiency
- GLUT4, glucose transporter 4
- HSL, hormone sensitive lipase
- IGF-1, insulin-like growth factor 1
- IRS1, insulin receptor substrate 1
- MRI, magnetic resonance imaging
- PPARGC1A, peroxisome proliferator-activated receptor 1 gamma coactivator 1 α
- RPL13A, ribosomal protein L13a
- TG, triglycerides
- ZAG, zinc-α2-glycoprotein.
- adipocyte size
- adipose tissue
- glucose tolerance
- growth hormone deficiency
- growth hormone replacement therapy
- insulin sensitivity
- lipolysis
- oGTT, oral glucose tolerance test
- rhGH, recombinant human growth hormone
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Balaz M, Ukropcova B, Kurdiova T, Gajdosechova L, Vlcek M, Janakova Z, Fedeles J, Pura M, Gasperikova D, Smith SR, Tkacova R, Klimes I, Payer J, Wolfrum C, Ukropec J. Adipokine zinc-α2-glycoprotein regulated by growth hormone and linked to insulin sensitivity. Obesity (Silver Spring) 2015; 23:322-8. [PMID: 25098857 DOI: 10.1002/oby.20856] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 07/21/2014] [Indexed: 12/26/2022]
Abstract
OBJECTIVE Hypertrophic obesity is associated with impaired insulin sensitivity and lipid-mobilizing activity of zinc-α2-glycoprotein. Adipose tissue (AT) of growth hormone (GH) -deficient patients is characterized by extreme adipocyte hypertrophy due to defects in AT lipid metabolism. It was hypothesized that zinc-α2-glycoprotein is regulated by GH and mediates some of its beneficial effects in AT. METHODS AT from patients with GH deficiency and individuals with obesity-related GH deficit was obtained before and after 5-year and 24-month GH supplementation therapy. GH action was tested in primary human adipocytes. Relationships of GH and zinc-α2-glycoprotein with adipocyte size and insulin sensitivity were evaluated in nondiabetic patients with noncancerous cachexia and hypertrophic obesity. RESULTS AT in GH-deficient adults displayed a substantial reduction of zinc-α2-glycoprotein. GH therapy normalized AT zinc-α2-glycoprotein. Obesity-related relative GH deficit was associated with almost 80% reduction of zinc-α2-glycoprotein mRNA in AT. GH increased zinc-α2-glycoprotein mRNA in both AT of obese men and primary human adipocytes. Interdependence of GH and zinc-α2-glycoprotein in regulating AT morphology and metabolic phenotype was evident from their relationship with adipocyte size and AT-specific and whole-body insulin sensitivity. CONCLUSIONS The results demonstrate that GH is involved in regulation of AT zinc-α2-glycoprotein; however, the molecular mechanism linking GH and zinc-α2-glycoprotein in AT is yet unknown.
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Affiliation(s)
- Miroslav Balaz
- Institute of Experimental Endocrinology, Slovak Academy of Sciences, Bratislava, Slovakia
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Balaz M, Vician M, Janakova Z, Kurdiova T, Surova M, Imrich R, Majercikova Z, Penesova A, Vlcek M, Kiss A, Belan V, Klimes I, Olejnik J, Gasperikova D, Wolfrum C, Ukropcova B, Ukropec J. Subcutaneous adipose tissue zinc-α2-glycoprotein is associated with adipose tissue and whole-body insulin sensitivity. Obesity (Silver Spring) 2014; 22:1821-9. [PMID: 24753506 DOI: 10.1002/oby.20764] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 03/17/2014] [Accepted: 04/04/2014] [Indexed: 12/17/2022]
Abstract
OBJECTIVE To examine the regulatory aspects of zinc-α2-glycoprotein (ZAG) association with obesity-related insulin resistance. METHODS ZAG mRNA and protein were analyzed in subcutaneous adipose tissue (AT) and circulation of lean, obese, prediabetic, and type 2 diabetic men; both subcutaneous and visceral AT were explored in lean and extremely obese. Clinical and ex vivo findings were corroborated by results of in vitro ZAG silencing experiment. RESULTS Subcutaneous AT ZAG was reduced in obesity, with a trend to further decrease with prediabetes and type 2 diabetes. ZAG was 3.3-fold higher in subcutaneous than in visceral AT of lean individuals. All differences were lost in extreme obesity. Obesity-associated changes in AT were not paralleled by alterations of circulating ZAG. Subcutaneous AT ZAG correlated with adiposity, adipocyte hypertrophy, whole-body and AT insulin sensitivity, mitochondrial content, expression of GLUT4, PGC1α, and adiponectin. Subcutaneous AT ZAG and adipocyte size were the only predictors of insulin sensitivity, independent on age and BMI. Silencing ZAG resulted in reduced adiponectin, IRS1, GLUT4, and PGC1α gene expression in primary human adipocytes. CONCLUSIONS ZAG in subcutaneous, but not in visceral AT, was markedly reduced in obesity. Clinical, cellular, and molecular evidence indicate that ZAG plays an important role in modulating whole-body and AT insulin sensitivity.
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Affiliation(s)
- Miroslav Balaz
- Institute of Experimental Endocrinology, Slovak Academy of Sciences, Bratislava, Slovakia
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Obesity, inflammation, and lung injury (OILI): the good. Mediators Inflamm 2014; 2014:978463. [PMID: 24899788 PMCID: PMC4037577 DOI: 10.1155/2014/978463] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Accepted: 03/19/2014] [Indexed: 01/13/2023] Open
Abstract
Obesity becomes pandemic, predisposing these individuals to great risk for lung injury. In this review, we focused on the anti-inflammatories and addressed the following aspects: adipocytokines and obesity, inflammation and other mechanisms, adipocytokines and lung injury in obesity bridged by inflammation, and potential therapeutic targets. To sum up, the majority of evidence supported that adiponectin, omentin, and secreted frizzled-related protein 5 (SFRP5) were reduced significantly in obesity, which is associated with increased inflammation, indicated by increase of TNFα and IL-6, through activation of toll-like receptor (TLR4) and nuclear factor light chain κB (NF-κB) signaling pathways. Administration of these adipocytokines promotes weight loss and reduces inflammation. Zinc-α2-glycoprotein (ZAG), vaspin, IL-10, interleukin-1 receptor antagonist (IL-1RA), transforming growth factor β (TGF-β1), and growth differentiation factor 15 (GDF15) are also regarded as anti-inflammatories. There were controversial reports. Furthermore, there is a huge lack of studies for obesity related lung injury. The effects of adiponectin on lung transplantation, asthma, chronic obstructive pulmonary diseases (COPD), and pneumonia were anti-inflammatory and protective in lung injury. Administration of IL-10 agonist reduces mortality of acute lung injury in rabbits with acute necrotizing pancreatitis, possibly through inhibiting proinflammation and strengthening host immunity. Very limited information is available for other adipocytokines.
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Serum Levels of the Adipokine Zinc- α 2-glycoprotein Are Decreased in Patients with Hypertension. ISRN ENDOCRINOLOGY 2014; 2014:374090. [PMID: 24665369 PMCID: PMC3934454 DOI: 10.1155/2014/374090] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 12/22/2013] [Indexed: 01/28/2023]
Abstract
Objective. Zinc-α2-glycoprotein (ZAG) has recently been proposed as a new adipokine involved in body weight regulation. The purpose of this study is to investigate serum levels of ZAG in patients with hypertension and its association with related characteristics. Methods. 32 hypertension patients and 42 normal controls were recruited and the relationship between serum ZAG, total and high molecular weight (HMW) adiponectin, and tumor necrosis factor-α (TNFα) determined by enzyme-linked immunosorbent assay (ELISA) and metabolic-related parameters was investigated. Results. Serum ZAG concentrations were significantly lowered in patients with hypertension compared with healthy controls (61.4 ± 32 versus 78.3 ± 42 μg/mL, P < 0.05). The further statistical analysis demonstrated that serum ZAG levels were negatively correlated with waist-to-hip ratio (WHR) (r = −0.241, P < 0.05) and alanine aminotransferase (ALT) (r = −0.243, P < 0.05). Additionally, serum HMW adiponectin significantly decreased, while TNFα greatly increased in hypertension patients as compared with healthy controls (2.32 ± 0.41 versus 5.24 ± 1.02 μg/mL, 3.30 ± 1.56 versus 2.34 ± 0.99 pg/mL, P < 0.05). Conclusions. Serum ZAG levels are significantly lowered in hypertension patients and negatively correlated with obesity-related item WHR, suggesting ZAG is a factor associated with hypertension.
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Arch JRS, Trayhurn P. Detection of thermogenesis in rodents in response to anti-obesity drugs and genetic modification. Front Physiol 2013; 4:64. [PMID: 23580228 PMCID: PMC3619105 DOI: 10.3389/fphys.2013.00064] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 03/16/2013] [Indexed: 11/22/2022] Open
Abstract
Many compounds and genetic manipulations are claimed to confer resistance to obesity in rodents by raising energy expenditure. Examples taken from recent and older literature, demonstrate that such claims are often based on measurements of energy expenditure after body composition has changed, and depend on comparisons of energy expenditure divided by body weight. This is misleading because white adipose tissue has less influence than lean tissue on energy expenditure. Application of this approach to human data would suggest that human obesity is usually due to a low metabolic rate, which is not an accepted view. Increased energy expenditure per animal is a surer way of demonstrating thermogenesis, but even then it is important to know whether this is due to altered body composition (repartitioning), or increased locomotor activity rather than thermogenesis per se. Regression analysis offers other approaches. The thermogenic response to some compounds has a rapid onset and so cannot be due to altered body composition. These compounds usually mimic or activate the sympathetic nervous system. Thermogenesis occurs in, but may not be confined to, brown adipose tissue. It should not be assumed that weight loss in response to these treatments is due to thermogenesis unless there is a sustained increase in 24-h energy expenditure. Thyroid hormones and fibroblast growth factor 21 also raise energy expenditure before they affect body composition. Some treatments and genetic modifications alter the diurnal rhythm of energy expenditure. It is important to establish whether this is due to altered locomotor activity or efficiency of locomotion. There are no good examples of compounds that do not affect short-term energy expenditure but have a delayed effect. How and under what conditions a genetic modification or compound increases energy expenditure influences the decision on whether to seek drugs for the target or take a candidate drug into clinical studies.
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Adipokines in obesity. Clin Chim Acta 2013; 419:87-94. [DOI: 10.1016/j.cca.2013.02.003] [Citation(s) in RCA: 178] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Revised: 02/05/2013] [Accepted: 02/10/2013] [Indexed: 12/11/2022]
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Zhu HJ, Ding HH, Deng JY, Pan H, Wang LJ, Li NS, Wang XQ, Shi YF, Gong FY. Inhibition of preadipocyte differentiation and adipogenesis by zinc-α2-glycoprotein treatment in 3T3-L1 cells. J Diabetes Investig 2013; 4:252-60. [PMID: 24843663 PMCID: PMC4015661 DOI: 10.1111/jdi.12046] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Revised: 10/29/2012] [Accepted: 11/27/2012] [Indexed: 12/19/2022] Open
Abstract
Aims/Introduction Zinc‐α2‐glycoprotein (ZAG) is associated with the loss of adipose tissue in cancer cachexia, and has recently been proposed to be a candidate factor in the regulation of bodyweight. The aim of the study was to investigate the effects of ZAG on the proliferation and differentiation of 3T3‐L1 preadipocytes. Materials and Methods 3‐(4,5‐Dimethylthiazol‐2‐yl) 2,5‐diphenyl tetrazolium bromide (MTT) spectrophotometry, Oil Red O staining, intracellular triglyceride assays, real‐time quantitative reverse transcription polymerase chain reaction and transient transfection methods were used to explore the action of ZAG. Results Ectopic ZAG expression significantly stimulates 3T3‐L1 cells proliferation in a dose‐ and time‐dependent manner. The maximum influence of ZAG on proliferation was 1.43‐fold higher than what was observed in control cells. This effect was observed 144 h after transfection with 0.16 μg of murine ZAG (mZAG) plasmid (P < 0.001). The intracellular lipids content in mZAG over‐expressing cells were decreased as much as 37% when compared with the control cells after differentiation (P < 0.05, P < 0.01). The messenger ribonucleic acid levels of peroxisome proliferators‐activated receptor‐γ (PPARγ), CCAAT enhancer‐binding protein‐α (C/EBPα) and the critical lipogenic gene, fatty acid synthase (FAS), are also downregulated by up to 50% in fully differentiated ZAG‐treated adipocytes. ZAG suppresses FAS messenger ribonucleic acid expression by reducing FAS promoter activity. Conclusions Zinc‐α2‐glycoprotein stimulates the proliferation and inhibits the differentiation of 3T3‐L1 murine preadipocytes. The inhibitory action of ZAG on cell differentiation might be a result of the attenuation of the expression of PPARγ, C/EBPα and the lipogenic‐specific enzyme FAS by reducing FAS promoter activity.
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Affiliation(s)
- Hui-Juan Zhu
- Department of Endocrinology Key Laboratory of Endocrinology of Ministry of Health Peking Union Medical College Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China
| | - Hui-Hua Ding
- Department of Endocrinology Key Laboratory of Endocrinology of Ministry of Health Peking Union Medical College Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China ; Department of Rheumatology Renji Hospital, School of Medicine Shanghai Jiao Tong University Shanghai China
| | - Jie-Ying Deng
- Department of Endocrinology Key Laboratory of Endocrinology of Ministry of Health Peking Union Medical College Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China
| | - Hui Pan
- Department of Endocrinology Key Laboratory of Endocrinology of Ministry of Health Peking Union Medical College Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China
| | - Lin-Jie Wang
- Department of Endocrinology Key Laboratory of Endocrinology of Ministry of Health Peking Union Medical College Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China
| | - Nai-Shi Li
- Department of Endocrinology Key Laboratory of Endocrinology of Ministry of Health Peking Union Medical College Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China
| | - Xiang-Qing Wang
- Department of Endocrinology Key Laboratory of Endocrinology of Ministry of Health Peking Union Medical College Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China
| | - Yi-Fan Shi
- Department of Endocrinology Key Laboratory of Endocrinology of Ministry of Health Peking Union Medical College Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China
| | - Feng-Ying Gong
- Department of Endocrinology Key Laboratory of Endocrinology of Ministry of Health Peking Union Medical College Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China
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Wargent ET, O'Dowd JF, Zaibi MS, Gao D, Bing C, Trayhurn P, Cawthorne MA, Arch JRS, Stocker CJ. Contrasts between the effects of zinc-α2-glycoprotein, a putative β3/2-adrenoceptor agonist and the β3/2-adrenoceptor agonist BRL35135 in C57Bl/6 (ob/ob) mice. J Endocrinol 2013; 216:157-68. [PMID: 23151357 DOI: 10.1530/joe-12-0402] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Previous studies by Tisdale et al. have reported that zinc-α(2)-glycoprotein (ZAG (AZGP1)) reduces body fat content and improves glucose homeostasis and the plasma lipid profile in Aston (ob/ob) mice. It has been suggested that this might be mediated via agonism of β(3)- and possibly β(2)-adrenoceptors. We compared the effects of dosing recombinant human ZAG (100 μg, i.v.) and BRL35135 (0.5 mg/kg, i.p.), which is in rodents a 20-fold selective β(3)- relative to β(2)-adrenoceptor agonist, given once daily for 10 days to male C57Bl/6 Lep(ob)/Lep(ob) mice. ZAG, but not BRL35135, reduced food intake. BRL35135, but not ZAG, increased energy expenditure acutely and after sub-chronic administration. Only BRL35135 increased plasma concentrations of glycerol and non-esterified fatty acid. Sub-chronic treatment with both ZAG and BRL35135 reduced fasting blood glucose and improved glucose tolerance, but the plasma insulin concentration 30 min after administration of glucose was lowered only by BRL35135. Both ZAG and BRL35135 reduced β(1)-adrenoceptor mRNA levels in white adipose tissue, but only BRL35135 reduced β(2)-adrenoceptor mRNA. Both ZAG and BRL35135 reduced β(1)-adrenoceptor mRNA levels in brown adipose tissue, but neither influenced β(2)-adrenoceptor mRNA, and only BRL35135 increased β(3)-adrenoceptor and uncoupling protein-1 (UCP1) mRNA levels in brown adipose tissue. Thus, ZAG and BRL35135 had similar effects on glycaemic control and shared some effects on β-adrenoceptor gene expression in adipose tissue, but ZAG did not display the thermogenic effects of the β-adrenoceptor agonist, nor did it increase β(3)-adrenoceptor or UCP1 gene expression in brown adipose tissue. ZAG does not behave as a typical β(3/2)-adrenoceptor agonist.
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Affiliation(s)
- Edward T Wargent
- Clore Laboratory, University of Buckingham, Hunter Street, Buckingham MK18 1EG, UK
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McDermott L, Jadoon A, Cunningham P. ZAG and a potential role in systemic lipid homeostastis: examining the evidence from in vitro human studies and patients with chronic illness. ACTA ACUST UNITED AC 2012. [DOI: 10.2217/clp.12.45] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Bagherani N. The Newest Hypothesis about Vitiligo: Most of the Suggested Pathogeneses of Vitiligo Can Be Attributed to Lack of One Factor, Zinc-α2-Glycoprotein. ISRN DERMATOLOGY 2012; 2012:405268. [PMID: 22778983 PMCID: PMC3388346 DOI: 10.5402/2012/405268] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Accepted: 04/18/2012] [Indexed: 11/23/2022]
Abstract
Zinc-α2-glycoprotein (ZAG) is a recently identified adipokine, assigned to the chromosome 7q22.1. It is a multidisciplinary protein, which is secreted in various body fluids. The ZAG plays roles in lipolysis, regulation of metabolism, cell proliferation and differentiation, regulation of melanin synthesis, cell adhesion, immunoregulation, and so forth. Vitiligo is the most common depigmenting skin disorder, characterized by acquired, progressive, and circumscribed amelanosis of the skin and hair. It commonly begins in childhood or young adulthood. The pathogenesis of this disorder is uncertain, but it appears to be dependent on the interaction of genetic, immunological, and neurological factors. For the first time, we pointed the probable association between ZAG and vitiligo. Herein, I have described this association in different views. By confirming this association, a surprising progression will occur in the treatment of this prevalent debilitating disease.
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Affiliation(s)
- Nooshin Bagherani
- Nooshin Bagherani's Office, 2nd Floor, Taha Physicians' Building, 40-Meter Street, Khoramshahr, Khuzestan Province, Iran
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Russell ST, Tisdale MJ. Role of β-adrenergic receptors in the anti-obesity and anti-diabetic effects of zinc-α2-glycoprotien (ZAG). Biochim Biophys Acta Mol Cell Biol Lipids 2011; 1821:590-9. [PMID: 22227600 DOI: 10.1016/j.bbalip.2011.12.003] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Revised: 12/13/2011] [Accepted: 12/14/2011] [Indexed: 01/03/2023]
Abstract
OBJECTIVES The goal of the current study is to determine whether the β-adrenoreceptor (β-AR) plays a role in the anti-obesity and anti-diabetic effects of zinc-α2-glycoprotein (ZAG). MATERIAL AND METHODS This has been investigated in CHO-K1 cells transfected with the human β1-, β2-, β3-AR and in ob/ob mice. Cyclic AMP assays were carried out along with binding studies. Ob/ob mice were treated with ZAG and glucose transportation and insulin were examined in the presence or absence of propranolol. RESULTS ZAG bound to the β3-AR with higher affinity (Kd 46±1nM) than the β2-AR (Kd 71±3nM) while there was no binding to the β1-AR, and this correlated with the increases in cyclic AMP in CHO-K1 cells transfected with the various β-AR and treated with ZAG. Treatment of ob/ob mice with ZAG increased protein expression of β3-AR in gastrocnemius muscle, and in white and brown adipose tissues, but had no effect on expression of β1- and β2-AR. A reduction of body weight was seen and urinary glucose excretion, increase in body temperature, reduction in maximal plasma glucose and insulin levels in the oral glucose tolerance test, and stimulation of glucose transport into skeletal muscle and adipose tissue, were completely attenuated by the non-specific β-AR antagonist propranolol. CONCLUSION The results suggest that the effects of ZAG on body weight and insulin sensitivity in ob/ob mice are manifested through a β-3AR, or possibly a β2-AR.
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Affiliation(s)
- Steven Thomas Russell
- Nutritional Biomedicine, School of Health Sciences, Aston University, Birmingham B4 7ET, UK.
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