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Lim S, Lee SH, Min KW, Lee CB, Kim SY, Yoo HJ, Kim NH, Kim JH, Oh S, Won JC, Kwon HS, Kim MK, Park JH, Jeong IK, Kim S. A multicentre, double-blind, placebo-controlled, randomized, parallel comparison, phase 3 trial to evaluate the efficacy and safety of pioglitazone add-on therapy in type 2 diabetic patients treated with metformin and dapagliflozin. Diabetes Obes Metab 2024; 26:2188-2198. [PMID: 38425186 DOI: 10.1111/dom.15526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 02/12/2024] [Accepted: 02/12/2024] [Indexed: 03/02/2024]
Abstract
AIM To investigate the efficacy and safety of pioglitazone compared to placebo when added to metformin plus dapagliflozin, a sodium-glucose cotransporter-2 (SGLT2) inhibitor, for patients with type 2 diabetes mellitus (T2DM). MATERIALS AND METHODS In a multicentre study, with a randomized, double-blind, placebo-controlled design, 249 Korean patients with T2DM suboptimally managed on metformin and dapagliflozin were assigned to receive either pioglitazone (15 mg daily) or placebo for 24 weeks, followed by a 24-week pioglitazone extension. Primary outcomes included changes in glycated haemoglobin (HbA1c), with secondary outcomes assessing insulin resistance, adiponectin levels, lipid profiles, liver enzymes, body weight and waist circumference. RESULTS Pioglitazone administration resulted in a significant reduction in HbA1c levels (from 7.80% ± 0.72% to 7.27% ± 0.82%) compared with placebo (from 7.79% ± 0.76% to 7.69% ± 0.86%, corrected mean difference: -0.42% ± 0.08%; p < 0.01) at 24 weeks. Additional benefits from pioglitazone treatment included enhanced insulin sensitivity, increased adiponectin levels, raised high-density lipoprotein cholesterol levels and reduced liver enzyme levels, resulting in improvement in nonalcoholic fatty liver disease liver fat score. Despite no serious adverse events in either group, pioglitazone therapy was modestly but significantly associated with weight gain and increased waist circumference. CONCLUSIONS Adjunctive pioglitazone treatment in T2DM inadequately controlled with metformin and dapagliflozin demonstrates considerable glycaemic improvement, metabolic benefits, and a low risk of hypoglycaemia. These advantages must be weighed against the potential for weight gain and increased waist circumference.
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Affiliation(s)
- Soo Lim
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seoul, South Korea
| | - Seung-Hwan Lee
- Department of Internal Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, South Korea
| | - Kyung-Wan Min
- Department of Internal Medicine, Eulji General Hospital, Eulji University School of Medicine, Seoul, South Korea
| | - Chang Beom Lee
- Department of Internal Medicine, Hanyang University Guri Hospital, Guri, South Korea
| | - Sang Yong Kim
- Department of Internal Medicine, Chosun University Hospital, Gwangju, South Korea
| | - Hye Jin Yoo
- Department of Internal Medicine, Korea University College of Medicine, Seoul, South Korea
| | - Nan Hee Kim
- Department of Internal Medicine, Korea University College of Medicine, Seoul, South Korea
| | - Jae Hyeon Kim
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea
| | - Seungjoon Oh
- Department of Endocrinology and Metabolism, Kyung Hee University Hospital, Kyung Hee University School of Medicine, Seoul, South Korea
| | - Jong Chul Won
- Department of Internal Medicine, Inje University Sanggye Paik Hospital, Seoul, South Korea
| | - Hyuk Sang Kwon
- Department of Internal Medicine, Yeouido St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, South Korea
| | - Mi Kyung Kim
- Department of Internal Medicine, Inje University Haeundae Paik Hospital, Inje University College of Medicine, Busan, South Korea
| | - Jung Hwan Park
- Department of Internal Medicine, Hanyang University College of Medicine, Seoul, South Korea
| | - In-Kyung Jeong
- Department of Endocrinology and Metabolism, Kyung Hee University Hospital at Gangdong, Kyung Hee University School of Medicine, Seoul, South Korea
| | - Sungrae Kim
- Department of Internal Medicine, Bucheon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Bucheon, South Korea
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Qiu Y, Gan M, Wang X, Liao T, Chen Q, Lei Y, Chen L, Wang J, Zhao Y, Niu L, Wang Y, Zhang S, Zhu L, Shen L. The global perspective on peroxisome proliferator-activated receptor γ (PPARγ) in ectopic fat deposition: A review. Int J Biol Macromol 2023; 253:127042. [PMID: 37742894 DOI: 10.1016/j.ijbiomac.2023.127042] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 09/20/2023] [Accepted: 09/21/2023] [Indexed: 09/26/2023]
Abstract
Excessive expansion of adipocytes can have unhealthy consequences as excess free fatty acids enter other tissues and cause ectopic fat deposition by resynthesizing triglycerides. This lipid accumulation in various tissues is harmful and can increase the risk of related metabolic diseases such as type II diabetes, cardiovascular disease, and insulin resistance. Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear hormone receptor superfamily that play a key role in energy metabolism as fatty acid metabolism sensors, and peroxisome proliferator-activated receptor γ (PPARγ) is the main subtype responsible for fat cell differentiation and adipogenesis. In this paper, we introduce the main structure and function of PPARγ and its regulatory role in the process of lipogenesis in the liver, kidney, skeletal muscle, and pancreas. This information can serve as a reference for further understanding the regulatory mechanisms and measures of the PPAR family in the process of ectopic fat deposition.
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Affiliation(s)
- Yanhao Qiu
- Farm Animal Genetic Resource Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Livestock and Poultry Multi-omics, Ministry of Agriculture and Rural Affairs, College of Animal and Technology, Sichuan Agricultural University, Chengdu 611130, China
| | - Mailin Gan
- Farm Animal Genetic Resource Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Livestock and Poultry Multi-omics, Ministry of Agriculture and Rural Affairs, College of Animal and Technology, Sichuan Agricultural University, Chengdu 611130, China
| | - Xingyu Wang
- Farm Animal Genetic Resource Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Livestock and Poultry Multi-omics, Ministry of Agriculture and Rural Affairs, College of Animal and Technology, Sichuan Agricultural University, Chengdu 611130, China
| | - Tianci Liao
- Farm Animal Genetic Resource Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Livestock and Poultry Multi-omics, Ministry of Agriculture and Rural Affairs, College of Animal and Technology, Sichuan Agricultural University, Chengdu 611130, China
| | - Qiuyang Chen
- Farm Animal Genetic Resource Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Livestock and Poultry Multi-omics, Ministry of Agriculture and Rural Affairs, College of Animal and Technology, Sichuan Agricultural University, Chengdu 611130, China
| | - Yuhang Lei
- Farm Animal Genetic Resource Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Livestock and Poultry Multi-omics, Ministry of Agriculture and Rural Affairs, College of Animal and Technology, Sichuan Agricultural University, Chengdu 611130, China
| | - Lei Chen
- Farm Animal Genetic Resource Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Livestock and Poultry Multi-omics, Ministry of Agriculture and Rural Affairs, College of Animal and Technology, Sichuan Agricultural University, Chengdu 611130, China
| | - Jinyong Wang
- Chongqing Academy of Animal Science, Rongchang, Chongqing 402460, China
| | - Ye Zhao
- Farm Animal Genetic Resource Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Livestock and Poultry Multi-omics, Ministry of Agriculture and Rural Affairs, College of Animal and Technology, Sichuan Agricultural University, Chengdu 611130, China
| | - Lili Niu
- Farm Animal Genetic Resource Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Livestock and Poultry Multi-omics, Ministry of Agriculture and Rural Affairs, College of Animal and Technology, Sichuan Agricultural University, Chengdu 611130, China
| | - Yan Wang
- Farm Animal Genetic Resource Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Livestock and Poultry Multi-omics, Ministry of Agriculture and Rural Affairs, College of Animal and Technology, Sichuan Agricultural University, Chengdu 611130, China
| | - Shunhua Zhang
- Farm Animal Genetic Resource Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Livestock and Poultry Multi-omics, Ministry of Agriculture and Rural Affairs, College of Animal and Technology, Sichuan Agricultural University, Chengdu 611130, China
| | - Li Zhu
- Farm Animal Genetic Resource Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Livestock and Poultry Multi-omics, Ministry of Agriculture and Rural Affairs, College of Animal and Technology, Sichuan Agricultural University, Chengdu 611130, China.
| | - Linyuan Shen
- Farm Animal Genetic Resource Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, China; Key Laboratory of Livestock and Poultry Multi-omics, Ministry of Agriculture and Rural Affairs, College of Animal and Technology, Sichuan Agricultural University, Chengdu 611130, China.
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Zamani B, Tabatabizadeh SM, Gilasi H, Yazdani S. Effects of pioglitazone and linagliptin on glycemic control, lipid profile and hs-CRP in metformin-treated patients with type 2 diabetes: a comparative study. Horm Mol Biol Clin Investig 2023; 44:385-391. [PMID: 38143260 DOI: 10.1515/hmbci-2022-0070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 10/01/2023] [Indexed: 12/26/2023]
Abstract
OBJECTIVES The purpose of this study was to compare the effects of pioglitazone and linagliptin on glycemic control, lipid profile and high-sensitivity C-reactive protein (hs-CRP) parameters in patients with type 2 diabetes treated with metformin. METHODS The present randomized clinical trial was conducted on 60 patients with type 2 diabetes treated with metformin in the age range of 30-60 years. The participants with informed consent were randomly assigned to receive pioglitazone or linagliptin. The first intervention group (n=30) received 30 mg of pioglitazone daily and the second intervention group (n=30) received 5 mg of linagliptin daily for 12 weeks. Fasting blood samples were taken from patients at the baseline and after 12 weeks to measure related variables. The current study was approved in Kashan University of Medical Sciences (with the code of ethics of IR.KAUMS.MEDNT.REC.1398.016), and the Iranian Registry of Clinical Trials (with the registration number of IRCT20170513033941N66). RESULTS The linagliptin administration significantly reduced serum levels of fasting blood sugar (p=0.03), blood sugar 2 h after a meal (p=0.02), glycosylated hemoglobin (p=0.02) and hs-CRP (p=0.005) after 12 weeks compared with pioglitazone. In contrast, the pioglitazone administration significantly decreased triglyceride levels (p=0.01) and increased HDL-cholesterol (p=0.002) compared to linagliptin. In addition, the administration of both linagliptin and pioglitazone drugs had no significant effect on LDL-cholesterol, total cholesterol, systolic and diastolic blood pressure, creatinine and blood urea. CONCLUSIONS The present study demonstrated the superiority of linagliptin over pioglitazone for glycemic control, although pioglitazone compared to linagliptin showed greater efficacy in reducing triglycerides and raising HDL-cholesterol.
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Affiliation(s)
- Batool Zamani
- Autoimmune Diseases Research Center, Kashan University of Medical Sciences, Kashan, Iran
| | | | - Hamidreza Gilasi
- Department of Epidemiology and Biostatistics, Heath Faculty, Kashan University of Medical Science, Kashan, Iran
| | - Shadi Yazdani
- Student Research Committee, Kashan University of Medical Science, Kashan, Iran
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Colasante C, Bonilla-Martinez R, Berg T, Windhorst A, Baumgart-Vogt E. Peroxisomes during postnatal development of mouse endocrine and exocrine pancreas display cell-type- and stage-specific protein composition. Cell Tissue Res 2023:10.1007/s00441-023-03766-6. [PMID: 37126142 DOI: 10.1007/s00441-023-03766-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 03/15/2023] [Indexed: 05/02/2023]
Abstract
Peroxisomal dysfunction unhinges cellular metabolism by causing the accumulation of toxic metabolic intermediates (e.g. reactive oxygen species, very -chain fatty acids, phytanic acid or eicosanoids) and the depletion of important lipid products (e.g. plasmalogens, polyunsaturated fatty acids), leading to various proinflammatory and devastating pathophysiological conditions like metabolic syndrome and age-related diseases including diabetes. Because the peroxisomal antioxidative marker enzyme catalase is low abundant in Langerhans islet cells, peroxisomes were considered scarcely present in the endocrine pancreas. Recently, studies demonstrated that the peroxisomal metabolism is relevant for pancreatic cell functionality. During the postnatal period, significant changes occur in the cell structure and the metabolism to trigger the final maturation of the pancreas, including cell proliferation, regulation of energy metabolism, and activation of signalling pathways. Our aim in this study was to (i) morphometrically analyse the density of peroxisomes in mouse endocrine versus exocrine pancreas and (ii) investigate how the distribution and the abundance of peroxisomal proteins involved in biogenesis, antioxidative defence and fatty acid metabolism change during pancreatic maturation in the postnatal period. Our results prove that endocrine and exocrine pancreatic cells contain high amounts of peroxisomes with heterogeneous protein content indicating that distinct endocrine and exocrine cell types require a specific set of peroxisomal proteins depending on their individual physiological functions. We further show that significant postnatal changes occur in the peroxisomal compartment of different pancreatic cells that are most probably relevant for the metabolic maturation and differentiation of the pancreas during the development from birth to adulthood.
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Affiliation(s)
- Claudia Colasante
- Institute for Anatomy and Cell Biology, Medical Cell Biology, Justus Liebig -University, Aulweg 123, 35392, Giessen, Germany
| | - Rocio Bonilla-Martinez
- Institute for Anatomy and Cell Biology, Medical Cell Biology, Justus Liebig -University, Aulweg 123, 35392, Giessen, Germany
| | - Timm Berg
- Institute for Anatomy and Cell Biology, Medical Cell Biology, Justus Liebig -University, Aulweg 123, 35392, Giessen, Germany
| | - Anita Windhorst
- Institute for Medical Informatic, Justus Liebig University, Rudolf-Buchheim-Str. 6, 35392, Gießen, Germany
| | - Eveline Baumgart-Vogt
- Institute for Anatomy and Cell Biology, Medical Cell Biology, Justus Liebig -University, Aulweg 123, 35392, Giessen, Germany.
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5
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Huang X, Xia Z, Huang Y, Sun Y, Zhang L, Xiong W, Zhang Z. Combined therapy with pioglitazone and FGF21 mRNA synergistically ameliorates metabolic disorders in NAFLD rats. Heliyon 2023; 9:e15146. [PMID: 37123911 PMCID: PMC10133668 DOI: 10.1016/j.heliyon.2023.e15146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 03/08/2023] [Accepted: 03/28/2023] [Indexed: 04/03/2023] Open
Abstract
Background Current study aims to investigate the ameliorative effect of pioglitazone (PIO) combined with mRNA encoding FGF21 (termed mFGF21) on the metabolic disorders in rats with nonalcoholic fatty liver disease (NAFLD) and its potential mechanism. Methods In vitro functional activity of FGF21 protein expressed by mFGF21 was evaluated in human adipose-derived stem cells (hASCs). The pharmacokinetic profiles of FGF21 protein expressed by mFGF21 were investigated in normal SD rats and NAFLD rats, respectively. Results As the results, it showed that the PIO could enhanced in vitro functional activity of FGF21 protein expressed from mFGF21 in hASCs. Not only that, mFGF21 turns the body into a processing plant for endogenous protein expression, which enhanced the pharmacokinetic profiles of FGF21 proteins. Combined treatment with PIO and mFGF21 significantly reduced body weight, fasting blood glucose levels, insulin levels and lipid metabolism in NAFLD rats compared with control or both two monotherapy groups. The results of H&E staining and Western blot revealed that combined treatment with PIO and mFGF21 significantly decreased hepatic fat accumulation in NAFLD rats by activating the SHP1/AMPK signaling pathway. Conclusions Our finding collectively demonstrated that PIO and mFGF21 combination therapy could synergistically ameliorate metabolic disorders in NAFLD rats.
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Brownrigg GP, Xia YH, Chu CMJ, Wang S, Chao C, Zhang JA, Skovsø S, Panzhinskiy E, Hu X, Johnson JD, Rideout EJ. Sex differences in islet stress responses support female β cell resilience. Mol Metab 2023; 69:101678. [PMID: 36690328 PMCID: PMC9971554 DOI: 10.1016/j.molmet.2023.101678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 01/07/2023] [Accepted: 01/17/2023] [Indexed: 01/21/2023] Open
Abstract
OBJECTIVE Pancreatic β cells play a key role in maintaining glucose homeostasis; dysfunction of this critical cell type causes type 2 diabetes (T2D). Emerging evidence points to sex differences in β cells, but few studies have examined male-female differences in β cell stress responses and resilience across multiple contexts, including diabetes. Here, we address the need for high-quality information on sex differences in β cell and islet gene expression and function using both human and rodent samples. METHODS In humans, we compared β cell gene expression and insulin secretion in donors with T2D to non-diabetic donors in both males and females. In mice, we generated a well-powered islet RNAseq dataset from 20-week-old male and female siblings with similar insulin sensitivity. Our unbiased gene expression analysis pointed to a sex difference in the endoplasmic reticulum (ER) stress response. Based on this analysis, we hypothesized female islets would be more resilient to ER stress than male islets. To test this, we subjected islets isolated from age-matched male and female mice to thapsigargin treatment and monitored protein synthesis, cell death, and β cell insulin production and secretion. Transcriptomic and proteomic analyses were used to characterize sex differences in islet responses to ER stress. RESULTS Our single-cell analysis of human β cells revealed sex-specific changes to gene expression and function in T2D, correlating with more robust insulin secretion in human islets isolated from female donors with T2D compared to male donors with T2D. In mice, RNA sequencing revealed differential enrichment of unfolded protein response pathway-associated genes, where female islets showed higher expression of genes linked with protein synthesis, folding, and processing. This differential expression was physiologically significant, as islets isolated from female mice were more resilient to ER stress induction with thapsigargin. Specifically, female islets showed a greater ability to maintain glucose-stimulated insulin production and secretion during ER stress compared with males. CONCLUSIONS Our data demonstrate sex differences in β cell gene expression in both humans and mice, and that female β cells show a greater ability to maintain glucose-stimulated insulin secretion across multiple physiological and pathological contexts.
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Affiliation(s)
- George P Brownrigg
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Yi Han Xia
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Chieh Min Jamie Chu
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Su Wang
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Charlotte Chao
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Jiashuo Aaron Zhang
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Søs Skovsø
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Evgeniy Panzhinskiy
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Xiaoke Hu
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - James D Johnson
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada.
| | - Elizabeth J Rideout
- Department of Cellular and Physiological Sciences, Life Sciences Institute, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada.
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Marmentini C, Guimarães DSPSF, de Lima TI, Teófilo FBS, da Silva NS, Soares GM, Boschero AC, Kurauti MA. Rosiglitazone protects INS-1E cells from human islet amyloid polypeptide toxicity. Eur J Pharmacol 2022; 928:175122. [PMID: 35764131 DOI: 10.1016/j.ejphar.2022.175122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Revised: 06/21/2022] [Accepted: 06/22/2022] [Indexed: 11/18/2022]
Abstract
Human islet amyloid polypeptide (hIAPP or amylin) is a hormone co-secreted with insulin by pancreatic β-cells, and is the main component of islet amyloid. Islet amyloid is found in the pancreas of patients with type 2 diabetes and may be involved in β-cell dysfunction and death, observed in this disease. Thus, counteracting islet amyloid toxicity represents a therapeutic approach to preserve β-cell mass and function. In this sense, thiazolidinediones (TZDs), as rosiglitazone, have shown protective effects against other harmful insults to β-cells. For this reason, we investigated whether rosiglitazone could protect β-cells from hIAPP-induced cell death and the underlying mechanisms mediating such effect. Here, we show that rosiglitazone improved the viability of hIAPP-exposed INS-1E cells. This benefit is not dependent on the insulin-degrading enzyme (IDE) since rosiglitazone did not modulate IDE protein content and activity. However, rosiglitazone inhibited hIAPP fibrillation and decreased hIAPP-induced expression of C/EBP homologous protein (CHOP) (CTL 100.0 ± 8.4; hIAPP 182.7 ± 19.1; hIAPP + RGZ 102.8 ± 9.5), activating transcription factor-4 (ATF4) (CTL 100.0 ± 3.1; hIAPP 234.9 ± 19.3; hIAPP + RGZ 129.6 ± 3.0) and phospho-eukaryotic initiation factor 2-alpha (p-eIF2α) (CTL 100.0 ± 31.1; hIAPP 234.1 ± 36.2; hIAPP + RGZ 150.4 ± 18.0). These findings suggest that TZDs treatment may be a promising approach to preserve β-cell mass and function by inhibiting islet amyloid formation and decreasing endoplasmic reticulum stress hIAPP-induced.
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Affiliation(s)
- Carine Marmentini
- Laboratory of Endocrine Pancreas and Metabolism, Obesity and Comorbidities Research Center (OCRC), University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
| | - Dimitrius Santiago P S F Guimarães
- Laboratory of Endocrine Pancreas and Metabolism, Obesity and Comorbidities Research Center (OCRC), University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
| | - Tanes I de Lima
- Laboratory of Endocrine Pancreas and Metabolism, Obesity and Comorbidities Research Center (OCRC), University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
| | - Francisco Breno S Teófilo
- Electron Microscopy Laboratory, Institute of Biology, University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
| | - Natália S da Silva
- Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
| | - Gabriela M Soares
- Laboratory of Endocrine Pancreas and Metabolism, Obesity and Comorbidities Research Center (OCRC), University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
| | - Antonio C Boschero
- Laboratory of Endocrine Pancreas and Metabolism, Obesity and Comorbidities Research Center (OCRC), University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
| | - Mirian A Kurauti
- Department of Physiological Sciences, Biological Sciences Center, State University of Maringa (UEM), Maringa, Parana, Brazil.
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El-Sayed K, Ali DA, Maher SA, Ghareeb D, Selim S, Albogami S, Fayad E, Kolieb E. Prophylactic and Ameliorative Effects of PPAR-γ Agonist Pioglitazone in Improving Oxidative Stress, Germ Cell Apoptosis and Inflammation in Gentamycin-Induced Testicular Damage in Adult Male Albino Rats. Antioxidants (Basel) 2022; 11:antiox11020191. [PMID: 35204074 PMCID: PMC8868260 DOI: 10.3390/antiox11020191] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 01/11/2022] [Accepted: 01/13/2022] [Indexed: 02/07/2023] Open
Abstract
Peroxisome proliferator-activated receptor gamma (PPAR-γ) is ubiquitously expressed in testicular tissue and plays a crucial role in regulating various physiological processes. Pioglitazone (PIO) is one of the PPAR-γ agonists, having anti-oxidant and anti-inflammatory effects. Patients on gentamycin treatment may undergo serious side effects such as testicular damage. To the best of our knowledge, this was the first study to investigate the possible protective anti-inflammatory and anti-apoptotic effects of PIO on gentamycin-induced testicular damage. Fifty adult male Wistar albino rats included in the study as the control group (CTL) received normal saline; a gentamycin-induced testicular damage group (GM) received gentamycin (100 mg/kg); PIO5, PIO10, PIO20 groups received PIO at a dose of 5, 10, and 20 mg/ kg, respectively, for 21 days, and gentamycin was started at day 15 of the experiment for 6 days. The parameters of spermatozoa and histopathological alterations in the testes were significantly improved in the PIO20 group. Moreover, MDA levels, inflammatory mediators, and apoptotic Bax expression were decreased. The activity of glutathione peroxidase, catalase, total antioxidant capacity, and anti-apoptotic Bcl-2 genes expression were increased. It was concluded that PIO20 could protect against gentamycin-induced testicular damage in Wistar rats through its anti-oxidant, anti-inflammatory, and antiapoptotic effects.
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Affiliation(s)
- Karima El-Sayed
- Physiology Department, Faculty of Medicine, Suez Canal University, Ismailia 41522, Egypt;
| | - Dina A. Ali
- Clinical Pharmacology Department, Faculty of Medicine, Suez Canal University, Ismailia 41522, Egypt;
| | - Shymaa Ahmed Maher
- Medical Biochemistry and Molecular Biology Department, Faculty of Medicine, Suez Canal University, Ismailia 41522, Egypt;
- Center of Excellence in Molecular and Cellular Medicine (CEMCM), Faculty of Medicine, Suez Canal University, Ismailia 41522, Egypt
| | - Dalia Ghareeb
- Clinical Pathology Department, Faculty of Medicine, Suez University, Suez 41522, Egypt;
| | - Samy Selim
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Jouf University, Sakaka 72341, Saudi Arabia;
| | - Sarah Albogami
- Department of Biotechnology, Faculty of Sciences, Taif University, Taif 21944, Saudi Arabia; (S.A.); (E.F.)
| | - Eman Fayad
- Department of Biotechnology, Faculty of Sciences, Taif University, Taif 21944, Saudi Arabia; (S.A.); (E.F.)
| | - Eman Kolieb
- Physiology Department, Faculty of Medicine, Suez Canal University, Ismailia 41522, Egypt;
- Correspondence: ; Tel.: +20-1006738513
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Cayli S, Alimogullari E, Piskin I, Bilginoglu A, Nakkas H. Effect of pioglitazone on the expression of ubiquitin proteasome system and autophagic proteins in rat pancreas with metabolic syndrome. J Mol Histol 2021; 52:929-942. [PMID: 34410563 DOI: 10.1007/s10735-021-10013-1] [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: 07/26/2020] [Accepted: 08/10/2021] [Indexed: 11/28/2022]
Abstract
The metabolic syndrome (MetS) and pathologies associated with metabolic dysregulations a worldwide growing problem. Our previous study demonstrated that pioglitazone (PGZ) has beneficial effects on metabolic syndrome associated disturbances in the heart. However, mechanism mediating the molecular alterations of Ubiquitin proteasome system (UPS) and autophagy has not been investigated in rat pancreas with metabolic syndrome. For this reason, we first aimed to detect whether MetS effects on the expression of UPS (p97/VCP, SVIP, Ubiquitin) and autophagic (p62, LC3) proteins in rat pancreas. The second aim of the study was to find impact of pioglitazone on the expression of UPS and autophagic proteins in MetS rat pancreas. To answer these questions, metabolic syndrome induced rats were used as a model and treated with pioglitazone for 2 weeks. Pancreatic tissue injuries, fibrosis and lipid accumulation were evaluated histopathologically in control, MetS and MetS-PGZ groups. Apoptosis and cell proliferation of pancreatic islet cells were assessed in all groups. UPS and autophagic protein expressions of pancreas in all groups were detected by using immunohistochemistry, double-immunfluorescence and Western blotting. Compared with the controls, the rat fed with high sucrose exhibited signs of metabolic syndrome, such as higher body weight, insulin resistance, higher triglyceride level and hyperglycaemia. MetS rats showed pancreatic tissue degeneration, fibrosis and lipid accumulation when their pancreas were examined with Hematoxilen-eozin and Mallory trichrome staining. Metabolic, histopathologic parameters and cell proliferation showed greater improvement in MetS-PGZ rats and pioglitazone decreased apoptosis of islet cells. Moreover, SVIP, ubiquitin, LC3 and p62 expressions were significantly increased while only p97/VCP expression was significantly decreased in MetS-rat pancreas compared to control. PGZ treatment significantly decreased the MetS-induced increases in autophagy markers. Additionally, UPS and autophagy markers were found to colocalizated with insulin and glucagon. Colocalization ratio of UPS markers with insulin showed significant decrease in MetS rats and PGZ increased this ratio, whereas LC3-insulin colocalization displayed significant increase in MetS rats and PGZ reversed this effect. In conclusion, PGZ improved the pancreatic tissue degeneration by increasing the level of p97/VCP and decreasing autophagic proteins, SVIP and ubiquitin expressions in MetS-rats. Moreover, PGZ has an effect on the colocalization ratio of UPS and autophagy markers with insulin.
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Affiliation(s)
- Sevil Cayli
- Department of Histology and Embryology, Medical Faculty, Ankara Yıldırım Beyazıt University, 06800, Ankara, Turkey.
| | - Ebru Alimogullari
- Department of Histology and Embryology, Medical Faculty, Ankara Yıldırım Beyazıt University, 06800, Ankara, Turkey
| | - Ilkay Piskin
- Department of Histology and Embryology, Medical Faculty, Ankara Yıldırım Beyazıt University, 06800, Ankara, Turkey
| | - Ayca Bilginoglu
- Department of Biophysics, Medical Faculty, Ankara Yıldırım Beyazıt University, Ankara, Turkey
| | - Hilal Nakkas
- Department of Histology and Embryology, Medical Faculty, Ankara Yıldırım Beyazıt University, 06800, Ankara, Turkey
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10
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Hamouda HA, Mansour SM, Elyamany MF. Vitamin D Combined with Pioglitazone Mitigates Type-2 Diabetes-induced Hepatic Injury Through Targeting Inflammation, Apoptosis, and Oxidative Stress. Inflammation 2021; 45:156-171. [PMID: 34468908 DOI: 10.1007/s10753-021-01535-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2021] [Accepted: 08/04/2021] [Indexed: 12/31/2022]
Abstract
Inflammation is a major pathophysiological factor in development of type-2 diabetes mellitus (T2DM). Vitamin D (VITD) plays an imperative role in modulation of several inflammatory responses. The current study aimed to investigate the possible beneficial effects of coadministration of VITD with pioglitazone (PIO), a PPAR-γ agonist, in fructose/streptozotocin (F/STZ) T2DM model in male Wistar rats. T2DM was induced by maintaining rats on 10% (w/v) fructose in drinking water for 9 weeks with an intraperitoneal injection of sub-diabetogenic dose of STZ (35 mg/kg) by the end of the fourth week. One week after STZ injection, PIO (10 mg/kg/day) alone or with VITD (500 IU/kg/day) was administered orally to diabetic rats till the end of the experiment. Blood samples were collected, livers were homogenized to determine biochemical parameters, and samples of livers were fixed in 10% formalin in saline for histological examination. Administration of PIO alone improved diabetes-induced inflammatory and oxidative states besides controlling hyperglycemia and decreasing apoptosis. Coadministration of VIT D with PIO promoted additional improvement in glycemic and lipid profiles, provided further control on diabetic-induced hepatic inflammation evident by downregulating TLR2, TLR4, and IKK-β while upregulating IκB-α expression and reducing inflammatory cytokines namely; NF-κB, TNF-α, IL-6, and IL-1β, decreasing apoptosis and oxidative stress by hampering caspase-3 and MDA contents, respectively, and improved liver histology than PIO alone. These beneficial effects of VIT D may expand its use by diabetics combined with antidiabetic drugs due to its anti-inflammatory, antioxidant, and antiapoptotic properties.
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Affiliation(s)
- Hend A Hamouda
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Cairo, Egypt. .,Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Cairo, Egypt.
| | - Suzan M Mansour
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Cairo, Egypt.,Department of Pharmacology, Toxicology and Biochemistry, Faculty of Pharmacy, Future University in Egypt, Cairo, Egypt
| | - Mohammed F Elyamany
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Cairo, Egypt
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11
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Carboni E, Carta AR, Carboni E. Can pioglitazone be potentially useful therapeutically in treating patients with COVID-19? Med Hypotheses 2020; 140:109776. [PMID: 32344313 PMCID: PMC7175844 DOI: 10.1016/j.mehy.2020.109776] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 04/21/2020] [Indexed: 01/08/2023]
Abstract
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a pandemic disease (COVID-19) that has spread globally causing more than 30,000 deaths. Despite the immense and ongoing global effort, no efficacious drugs to fight this plague have been identified and patients admitted to the intensive care units (ICU), for respiratory distress, are managed mostly by means of supportive care based on oxygen maintenance. Several authors have reported that the prevalence of hypertension, diabetes, cardiovascular and cerebrovascular diseases comorbidities were indeed frequent among patients with COVID-19, which suggests that these conditions are likely to aggravate and complicate the prognosis. What the aforementioned diseases have in common is a latent chronic inflammatory state that may be associated with the alteration of laboratory parameters that are typical of the metabolic syndrome and insulin resistance. In severe COVID-19 patients laboratory markers of inflammation such as C-reactive protein, IL-6, D-dimer, serum ferritin and lactate dehydrogenase are elevated in many patients; assessed since the 4th-6th day of illness onset, such increases seem to be predictive of an adverse prognosis. Our hypothesis is that drugs belonging to the family of thiazolidinediones (TZD) such as pioglitazone or rosiglitazone, approved for treating the condition of insulin resistance and the accompanying inflammation, could ameliorate the prognosis of those COVID-19 patients with diabetes, hypertension and cardiovascular disorders comorbidities. TZD are PPARγ agonists that act on nuclear receptors, thereby triggering certain transcription factors. TZD were widely used for type-2 diabetes in the first decade of this century and although concerns have been raised for possible side effects associated with long-term treatment, their use has been recently revaluated for their anti-inflammatory properties in numerous medical conditions.
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Affiliation(s)
- Elena Carboni
- Department of Paediatrics, Magna Graecia University of Catanzaro, Italy
| | - Anna R. Carta
- Department of Biomedical Sciences, University of Cagliari, Italy
| | - Ezio Carboni
- Department of Biomedical Sciences, University of Cagliari, Italy
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12
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Bansal G, Singh S, Monga V, Thanikachalam PV, Chawla P. Synthesis and biological evaluation of thiazolidine-2,4-dione-pyrazole conjugates as antidiabetic, anti-inflammatory and antioxidant agents. Bioorg Chem 2019; 92:103271. [DOI: 10.1016/j.bioorg.2019.103271] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2019] [Revised: 09/02/2019] [Accepted: 09/09/2019] [Indexed: 01/02/2023]
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13
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Kwon MJ, Lee YJ, Jung HS, Shin HM, Kim TN, Lee SH, Rhee BD, Kim MK, Park JH. The direct effect of lobeglitazone, a new thiazolidinedione, on pancreatic beta cells: A comparison with other thiazolidinediones. Diabetes Res Clin Pract 2019; 151:209-223. [PMID: 30954516 DOI: 10.1016/j.diabres.2019.04.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 03/14/2019] [Accepted: 04/01/2019] [Indexed: 12/11/2022]
Abstract
AIMS The direct effects of thiazolidinediones (TZDs) on pancreatic beta cells have been controversial. The aim of this study was to find out whether a novel TZD, lobeglitazone, has beneficial effects on pancreatic beta cells and db/db mice compared to those of other TZDs. METHODS INS-1 cells were incubated at a high-glucose concentration with various concentrations of troglitazone, rosiglitazone, pioglitazone, and lobeglitazone. Apoptosis and proliferation of beta cells, markers for ER stress and glucose-stimulated insulin secretion (GSIS) were assessed. In addition, C57BL/6 db/db mice were treated with pioglitazone or lobeglitazone for 4 weeks, and metabolic parameters and the configuration of pancreatic islets were also examined. RESULTS Lobeglitazone and other TZDs decreased INS-1 cell apoptosis in high-glucose conditions. Lobeglitazone and other TZDs significantly decreased hyperglycemia-induced increases in ER stress markers and increased GSIS. Metabolic parameters showed greater improvement in db/db mice treated with pioglitazone and lobeglitazone than in control mice. Islet size, cell proliferation, and beta cell mass were increased, and collagen surrounding the islets was decreased in treated mice. CONCLUSIONS Lobeglitazone showed beneficial effects on beta cell survival and function against hyperglycemia. The prosurvival and profunction effects of lobeglitazone were comparable to those of other TZDs.
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Affiliation(s)
- Min Jeong Kwon
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Inje University, Busan, Republic of Korea; Paik Institute for Clinical Research, Molecular Therapy Lab, Inje University, Busan, Republic of Korea
| | - Yong Jae Lee
- CKD Research Institute, Yongin, Gyeonggi-do, Republic of Korea
| | - Hye Sook Jung
- Paik Institute for Clinical Research, Molecular Therapy Lab, Inje University, Busan, Republic of Korea
| | - Hyun Mi Shin
- Paik Institute for Clinical Research, Molecular Therapy Lab, Inje University, Busan, Republic of Korea
| | - Tae Nyun Kim
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Inje University, Busan, Republic of Korea
| | - Soon Hee Lee
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Inje University, Busan, Republic of Korea
| | - Byoung Doo Rhee
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Inje University, Busan, Republic of Korea
| | - Mi-Kyung Kim
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Inje University, Busan, Republic of Korea; Paik Institute for Clinical Research, Molecular Therapy Lab, Inje University, Busan, Republic of Korea.
| | - Jeong Hyun Park
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Inje University, Busan, Republic of Korea; Paik Institute for Clinical Research, Molecular Therapy Lab, Inje University, Busan, Republic of Korea.
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14
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Kimura T, Obata A, Shimoda M, Okauchi S, Kanda-Kimura Y, Nogami Y, Moriuchi S, Hirukawa H, Kohara K, Nakanishi S, Mune T, Kaku K, Kaneto H. Protective effects of the SGLT2 inhibitor luseogliflozin on pancreatic β-cells in db/db mice: The earlier and longer, the better. Diabetes Obes Metab 2018; 20:2442-2457. [PMID: 29873444 DOI: 10.1111/dom.13400] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 05/14/2018] [Accepted: 05/25/2018] [Indexed: 02/06/2023]
Abstract
AIMS We compared the protective effects of sodium glucose co-transporter (SGLT) 2 inhibitor luseogliflozin on pancreatic β-cells between early and advanced stages of diabetes and between short- and long-term use. MATERIALS AND METHODS Diabetic db/db mice were treated with luseogliflozin for 2 weeks in an early stage of diabetes (7-9 weeks of age) and an advanced stage of diabetes (16-18 weeks) for a longer period of time (7-18 weeks). We performed various morphological analyses of pancreatic islets and examined gene expression profiles in islets after such treatment. RESULTS In diabetic db/db mice, insulin biosynthesis and secretion were markedly increased by luseogliflozin in an early stage of diabetes but not in an advanced stage. In addition, β-cell mass was preserved by luseogliflozin only in an early stage. Furthermore, when db/db mice were treated with luseogliflozin for a longer period of time, starting from an early stage, β-cell function and mass were markedly preserved even after a longer period of time compared to untreated db/db mice. CONCLUSION Luseogliflozin exerts more protective effects in an early stage of diabetes compared to an advanced stage, and longer-term use of luseogliflozin exerts more beneficial effects on pancreatic β-cells compared to short-term use.
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Affiliation(s)
- Tomohiko Kimura
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Okayama, Japan
| | - Atsushi Obata
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Okayama, Japan
| | - Masashi Shimoda
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Okayama, Japan
| | - Seizo Okauchi
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Okayama, Japan
| | - Yukiko Kanda-Kimura
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Okayama, Japan
| | - Yuka Nogami
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Okayama, Japan
| | - Saeko Moriuchi
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Okayama, Japan
| | - Hidenori Hirukawa
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Okayama, Japan
| | - Kenji Kohara
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Okayama, Japan
| | - Shuhei Nakanishi
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Okayama, Japan
| | - Tomoatsu Mune
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Okayama, Japan
| | - Kohei Kaku
- Department of General Internal Medicine 1, Kawasaki Hospital, Kawasaki Medical School, Okayama, Japan
| | - Hideaki Kaneto
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Okayama, Japan
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15
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Hirukawa H, Hashiramoto M, Tanizawa Y, Kaku K. Remission of hyperglycemia after withdrawal of oral antidiabetic drugs in Japanese patients with early-stage type 2 diabetes. J Diabetes Investig 2018; 9:1119-1127. [PMID: 29406607 PMCID: PMC6123043 DOI: 10.1111/jdi.12813] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 01/15/2018] [Accepted: 01/28/2018] [Indexed: 01/06/2023] Open
Abstract
AIMS/INTRODUCTION To assess whether intervention with oral antidiabetic drug in Japanese patients with the early stage of type 2 diabetes could provide a significant remission of the disease process. MATERIALS AND METHODS Patients with diabetes duration <5 years were randomized to the lifestyle modification (LFS), pioglitazone (PIO) or sulfonylurea (SU) treatment group. In phase 1 as the on-treatment period and in phase 2 as the off-treatment period, the duration that glycated hemoglobin (HbA1c) was maintained at less than the target was compared among groups. RESULTS A total of 278 patients were assigned to LFS (n = 84), PIO (n = 101) and SU (n = 93), and 212 patients completed phase 1. The number of patients that dropped out because of HbA1c elevation was larger in the LFS group, and the duration of HbA1c being maintained at <7.9% was longer in the SU group than the other groups. The duration of HbA1c being maintained at <7.4% in phase 2 was significantly shorter in the SU group than in the other groups. The proportion of patients who achieved HbA1c <6.9% or 6.2% at the end of phase 1 was obviously less in the LFS group than other groups. The duration of HbA1c being maintained at <6.2% in phase 2 was longer in the PIO group than other groups, although not significant statistically. An increase in serum adiponectin and decreases in high-sensitivity C-reactive protein and homeostatic model assessment of insulin resistance were shown in patients treated with PIO, but not LFS and SU, in phase 1, but were canceled in the drug-off phase 2 period. CONCLUSIONS PIO treatment provided a prolonged remission of hyperglycemia after stopping the dosage in patients with the early stage of type 2 diabetes.
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Affiliation(s)
- Hidenori Hirukawa
- Division of Diabetes, Endocrinology and MetabolismKawasaki Medical SchoolKurashikiOkayamaJapan
| | | | - Yukio Tanizawa
- Division of Endocrinology, Metabolism, Hematological Science and TherapeuticsYamaguchi University Graduate School of MedicineYamaguchiJapan
| | - Kohei Kaku
- Division of Diabetes, Endocrinology and MetabolismKawasaki Medical SchoolKurashikiOkayamaJapan
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16
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Nakamura T, Ichii O, Irie T, Kouguchi H, Sotozaki K, Chihara M, Sunden Y, Nagasaki KI, Tatsumi O, Elewa YHA, Kon Y. Cotton rat (Sigmodon hispidus) develops metabolic disorders associated with visceral adipose inflammation and fatty pancreas without obesity. Cell Tissue Res 2018; 375:483-492. [PMID: 30155650 DOI: 10.1007/s00441-018-2908-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Accepted: 08/07/2018] [Indexed: 12/27/2022]
Abstract
Obesity induces metabolic disorders such as type 2 diabetes, hypertension, and cardiovascular diseases and has become a global health concern. Recent studies imply that fat accumulation in nonadipose tissue correlates with metabolic disorders. However, there are no suitable animal models to evaluate this phenomenon. This study investigated the characteristics of metabolic disorders found in cotton rat (Sigmodon hispidus). Blood biochemical examinations revealed that cotton rats, predominantly males, developed hyperinsulinemia, hyperglycemia, and dyslipidemia when fed a normal diet. The islets increased in size through β-cell hyperplasia, which was associated with serum insulin level in both sexes, strongly indicating insulin resistance. In male cotton rats, oxidative stress was observed in β cells, and macrophage infiltration into the visceral white adipose tissue was reported, both of which were associated with serum insulin level without visceral obesity. In contrast, female cotton rats developed hyperinsulinemia without histopathological changes that were reported in males. Adipocytes were found to be accumulated in the pancreas but not in the liver of both sexes during aging. Pancreatic fat accumulation was associated with the serum insulin level only in females. Taken together, cotton rats developed metabolic disorders associated with visceral fat inflammation in the absence of obesity. In addition, pancreatic ectopic fat may also be related to the early stages of these conditions. Thus, the cotton rat may serve as a novel and useful model for metabolic disorders characterized by visceral adipose inflammation and ectopic fat accumulation in the pancreas without obesity.
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Affiliation(s)
- Teppei Nakamura
- Section of Biological Science, Chitose Laboratory, Japan Food Research Laboratories, Chitose, Hokkaido, 066-0052, Japan.,Laboratory of Anatomy, Division of Veterinary Medicine, Department of Basic Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, 060-0818, Japan
| | - Osamu Ichii
- Laboratory of Anatomy, Division of Veterinary Medicine, Department of Basic Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, 060-0818, Japan
| | - Takao Irie
- Medical Zoology Group, Department of Infectious Diseases, Hokkaido Institute of Public Health, Sapporo, Hokkaido, 060-0819, Japan
| | - Hirokazu Kouguchi
- Medical Zoology Group, Department of Infectious Diseases, Hokkaido Institute of Public Health, Sapporo, Hokkaido, 060-0819, Japan
| | - Kozue Sotozaki
- Sankyo Labo Service Corporation, Inc., Sapporo, Hokkaido, 004-0802, Japan
| | - Masataka Chihara
- Laboratory of Anatomy, Division of Veterinary Medicine, Department of Basic Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, 060-0818, Japan
| | - Yuji Sunden
- Laboratory of Veterinary Pathology, Faculty of Agriculture, Tottori University, Tottori, 680-0945, Japan
| | - Ken-Ichi Nagasaki
- Section of Biological Safety Research, Tama Laboratory, Japan Food Research Laboratories, Tama, Tokyo, 206-0025, Japan
| | - Osamu Tatsumi
- Section of Biological Science, Chitose Laboratory, Japan Food Research Laboratories, Chitose, Hokkaido, 066-0052, Japan
| | - Yaser Hosny Ali Elewa
- Laboratory of Anatomy, Division of Veterinary Medicine, Department of Basic Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, 060-0818, Japan.,Department of Histology and Cytology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, 44519, Egypt
| | - Yasuhiro Kon
- Laboratory of Anatomy, Division of Veterinary Medicine, Department of Basic Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, 060-0818, Japan.
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17
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Kimura T, Obata A, Shimoda M, Hirukawa H, Kanda-Kimura Y, Nogami Y, Kohara K, Nakanishi S, Mune T, Kaku K, Kaneto H. Durability of protective effect of dulaglutide on pancreatic β-cells in diabetic mice: GLP-1 receptor expression is not reduced despite long-term dulaglutide exposure. DIABETES & METABOLISM 2018. [DOI: 10.1016/j.diabet.2017.10.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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18
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Kapodistria K, Tsilibary EP, Kotsopoulou E, Moustardas P, Kitsiou P. Liraglutide, a human glucagon-like peptide-1 analogue, stimulates AKT-dependent survival signalling and inhibits pancreatic β-cell apoptosis. J Cell Mol Med 2018. [PMID: 29524296 PMCID: PMC5980190 DOI: 10.1111/jcmm.13259] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Liraglutide, a human long‐lasting GLP‐1 analogue, is currently regarded as a powerful treatment option for type 2 diabetes. Apart from glucoregulatory and insulinotropic actions, liraglutide increases β‐cell mass through stimulation of β‐cell proliferation and islet neogenesis, as well as inhibition of β‐cell apoptosis. However, the underline molecular mechanisms have not been fully characterized. In this study, we investigated the mechanism by which liraglutide preserves islet β‐cells in an animal model of overt diabetes, the obese db/db mice, and protects a mouse pancreatic β‐cell line (βTC‐6 cells) against apoptosis. Treatment of 12‐week‐old diabetic mice with liraglutide for 2 weeks had no appreciable effects on blood non‐fasting glucose concentration, islet insulin content and body weight. However, morphological and biochemical examination of diabetic mouse pancreatic islets demonstrated that liraglutide restores islet size, reduces islet β‐cell apoptosis and improves nephrin expression, a protein involved in β‐cell survival signalling. Our results indicated that liraglutide protects βTC‐6 cells from serum withdrawal‐induced apoptosis through inhibition of caspase‐3 activation. The molecular mechanism of the anti‐apoptotic action of liraglutide in βTC‐6‐cells comprises stimulation of PI3‐kinase‐dependent AKT phosphorylation leading to the phosphorylation, hence inactivation of the pro‐apoptotic protein BAD and inhibition of FoxO1 transcription factor. In conclusion, we provided evidence that the GLP‐1 analogue liraglutide exerts important beneficial effects on pancreatic islet architecture and β‐cell survival by protecting cells against apoptosis. These findings extend our understanding of the actions of liraglutide and further support the use of GLP‐1R agonists in the treatment of patients with type 2 diabetes.
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Affiliation(s)
- Katerina Kapodistria
- Institute of Biosciences and Applications, National Centre for Scientific Research, N.C.S.R. "Demokritos", Terma Patriarchou Grigoriou & Neapoleos, Attiki, Greece
| | - Effie-Photini Tsilibary
- Institute of Biosciences and Applications, National Centre for Scientific Research, N.C.S.R. "Demokritos", Terma Patriarchou Grigoriou & Neapoleos, Attiki, Greece
| | - Eleni Kotsopoulou
- Institute of Biosciences and Applications, National Centre for Scientific Research, N.C.S.R. "Demokritos", Terma Patriarchou Grigoriou & Neapoleos, Attiki, Greece
| | - Petros Moustardas
- Center for Clinical, Experimental Surgery and Translational Research, Biomedical Research Foundation Academy of Athens (BRFAA), Athens, Greece
| | - Paraskevi Kitsiou
- Institute of Biosciences and Applications, National Centre for Scientific Research, N.C.S.R. "Demokritos", Terma Patriarchou Grigoriou & Neapoleos, Attiki, Greece
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Davidson MA, Mattison DR, Azoulay L, Krewski D. Thiazolidinedione drugs in the treatment of type 2 diabetes mellitus: past, present and future. Crit Rev Toxicol 2017; 48:52-108. [PMID: 28816105 DOI: 10.1080/10408444.2017.1351420] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Thiazolidinedione (TZD) drugs used in the treatment of type 2 diabetes mellitus (T2DM) have proven effective in improving insulin sensitivity, hyperglycemia, and lipid metabolism. Though well tolerated by some patients, their mechanism of action as ligands of peroxisome proliferator-activated receptors (PPARs) results in the activation of several pathways in addition to those responsible for glycemic control and lipid homeostasis. These pathways, which include those related to inflammation, bone formation, and cell proliferation, may lead to adverse health outcomes. As treatment with TZDs has been associated with adverse hepatic, cardiovascular, osteological, and carcinogenic events in some studies, the role of TZDs in the treatment of T2DM continues to be debated. At the same time, new therapeutic roles for TZDs are being investigated, with new forms and isoforms currently in the pre-clinical phase for use in the prevention and treatment of some cancers, inflammatory diseases, and other conditions. The aims of this review are to provide an overview of the mechanism(s) of action of TZDs, a review of their safety for use in the treatment of T2DM, and a perspective on their current and future therapeutic roles.
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Affiliation(s)
- Melissa A Davidson
- a Faculty of Health Sciences , University of Ottawa , Ottawa , Canada.,b McLaughlin Centre for Population Health Risk Assessment , Ottawa , Canada
| | - Donald R Mattison
- b McLaughlin Centre for Population Health Risk Assessment , Ottawa , Canada.,c Risk Sciences International , Ottawa , Canada
| | - Laurent Azoulay
- d Center for Clinical Epidemiology , Lady Davis Research Institute, Jewish General Hospital , Montreal , Canada.,e Department of Oncology , McGill University , Montreal , Canada
| | - Daniel Krewski
- a Faculty of Health Sciences , University of Ottawa , Ottawa , Canada.,b McLaughlin Centre for Population Health Risk Assessment , Ottawa , Canada.,c Risk Sciences International , Ottawa , Canada.,f Faculty of Medicine , University of Ottawa , Ottawa , Canada
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Kaneto H, Obata A, Kimura T, Shimoda M, Okauchi S, Shimo N, Matsuoka TA, Kaku K. Beneficial effects of sodium-glucose cotransporter 2 inhibitors for preservation of pancreatic β-cell function and reduction of insulin resistance. J Diabetes 2017; 9:219-225. [PMID: 27754601 DOI: 10.1111/1753-0407.12494] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 09/29/2016] [Accepted: 10/12/2016] [Indexed: 02/06/2023] Open
Abstract
Type 2 diabetes mellitus is characterized by insulin resistance in various insulin target tissues, such as the liver, adipose tissue, and skeletal muscle, and insufficient insulin secretion from pancreatic β-cells. Sodium-glucose cotransporter 2 (SGLT2) inhibitors, which are newly developed antidiabetic agents, decrease blood glucose levels by enhancing urinary glucose excretion and thereby function in an insulin-independent manner. Sodium-glucose cotransporter 2 inhibitors exert beneficial effects to reduce insulin resistance and preserve pancreatic β-cell function. In addition, SGLT2 inhibitors exhibit a variety of beneficial effects in various insulin target tissues, such as amelioration of fatty liver, reduction of visceral fat mass, and increasing glucose uptake in skeletal muscle. Furthermore, SGLT2 inhibitors protect pancreatic β-cells against glucose toxicity and preserve insulin secretory capacity. Together, these observations indicate that SGLT2 inhibitors are promising newly developed antidiabetic agents that are gaining attention in both clinical medicine and basic research.
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Affiliation(s)
- Hideaki Kaneto
- Departments of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki, Japan
| | - Atsushi Obata
- Departments of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki, Japan
| | - Tomohiko Kimura
- Departments of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki, Japan
| | - Masashi Shimoda
- Departments of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki, Japan
| | - Seizo Okauchi
- Departments of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki, Japan
| | - Naoki Shimo
- Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Taka-Aki Matsuoka
- Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Kohei Kaku
- General Internal Medicine 1, Kawasaki Medical School, Kurashiki, Japan
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21
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Iizuka Y, Kim H, Izawa T, Sakurai K, Hirako S, Wada M, Matsumoto A. Protective effects of fish oil and pioglitazone on pancreatic tissue in obese KK mice with type 2 diabetes. Prostaglandins Leukot Essent Fatty Acids 2016; 115:53-59. [PMID: 27914514 DOI: 10.1016/j.plefa.2016.10.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 10/17/2016] [Accepted: 10/17/2016] [Indexed: 11/24/2022]
Abstract
n-3 Polyunsaturated fatty acids, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have protective effects against the pancreatic β-cell dysfunction through several mechanisms. Thiazolidines are insulin sensitizers and are used in treating patients with type 2 diabetes. Our previous study demonstrated that a combination of fish oil, which is rich with EPA and DHA, and pioglitazone exerts beneficial effects on obesity and diabetes through their actions on the liver and adipose tissue. However, it remains largely unknown whether such combination therapy affects the pancreas. To answer this question, KK mice, which serve as a model for obesity and type 2 diabetes, were treated for 8 weeks with fish oil and pioglitazone. The combined regimen suppressed pancreatic islet hypertrophy (mean islet area decreased by an average of 49% vs. control) compared with mice treated with fish oil or pioglitazone alone (decreased by an average of 21% and 32% vs. control, respectively). Compared with the controls, individual or combined treatment significantly increased the percentage of β-cell area in the pancreatic islets, significantly decreased endoplasmic reticulum stress, and reduced the percentage of apoptotic cell death in the pancreatic islets. These findings suggest that fish oil and/or pioglitazone prevents β-cell dysfunction by improving the insulin resistance and decreasing the ER stress.
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Affiliation(s)
- Yuzuru Iizuka
- Department of Clinical Dietetics & Human Nutrition, Faculty of Pharmaceutical Sciences, Josai University, Saitama, Japan
| | - Hyounju Kim
- Department of Clinical Dietetics & Human Nutrition, Faculty of Pharmaceutical Sciences, Josai University, Saitama, Japan.
| | - Takuya Izawa
- Department of Clinical Dietetics & Human Nutrition, Faculty of Pharmaceutical Sciences, Josai University, Saitama, Japan
| | - Koji Sakurai
- Department of Clinical Dietetics & Human Nutrition, Faculty of Pharmaceutical Sciences, Josai University, Saitama, Japan
| | - Satoshi Hirako
- Department of Health and Nutrition, University of Human Arts and Sciences, Saitama, Japan
| | - Masahiro Wada
- Department of Clinical Dietetics & Human Nutrition, Faculty of Pharmaceutical Sciences, Josai University, Saitama, Japan
| | - Akiyo Matsumoto
- Department of Clinical Dietetics & Human Nutrition, Faculty of Pharmaceutical Sciences, Josai University, Saitama, Japan
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22
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Mudgal J, Shetty P, Reddy ND, Akhila HS, Gourishetti K, Mathew G, Nayak PG, Kumar N, Kishore A, Kutty NG, Nandakumar K, Shenoy RR, Rao CM, Joseph A. In vivo Evaluation of Two Thiazolidin-4-one Derivatives in High Sucrose Diet Fed Pre-diabetic Mice and Their Modulatory Effect on AMPK, Akt and p38 MAP Kinase in L6 Cells. Front Pharmacol 2016; 7:381. [PMID: 27790148 PMCID: PMC5064669 DOI: 10.3389/fphar.2016.00381] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 09/30/2016] [Indexed: 01/06/2023] Open
Abstract
We had previously demonstrated the anti-diabetic potential and pancreatic protection of two thiazolidin-4-one derivatives containing nicotinamide moiety (NAT-1 and NAT-2) in STZ-induced diabetic mice. However, due to the limitations of the STZ model, we decided to undertake a detailed evaluation of anti-diabetic potential of the molecules on a high sucrose diet (HSD) fed diabetic mouse model. Further, in vitro mechanistic studies on the phosphorylation of AMPK, Akt and p38 MAP kinase in L6 myotubes and anti-inflammatory studies in RAW264.7 mouse monocyte macrophage cells were performed. 15 months of HSD induced fasting hyperglycaemia and impaired glucose tolerance in mice. Treatment with NAT-1 and NAT-2 (100 mg/kg) for 45 days significantly improved the glucose tolerance and lowered fasting blood glucose levels compared to untreated control. An improvement in the elevated triglycerides and total cholesterol levels, and favorable rise in HDL cholesterol were also observed with test drug treatment. Also, no major changes were observed in the liver (albumin, AST and ALT) and kidney (creatinine and urea) parameters. This was further confirmed in their respective histology profiles which revealed no gross morphological changes. In L6 cells, significant phosphorylation of Akt and p38 MAP kinase proteins were observed with 100 μM of NAT-1 and NAT-2 with no significant changes in phosphorylation of AMPK. The molecules failed to exhibit anti-inflammatory activity as observed by their effect on the generation of ROS and nitrite, and nuclear levels of NF-κB in LPS-stimulated RAW264.7 cells. In summary, the molecules activated Akt and p38 MAP kinase which could have partly contributed to their anti-hyperglycaemic and hypolipidemic activities in vivo.
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Affiliation(s)
- Jayesh Mudgal
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal University Manipal, India
| | - Priya Shetty
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal University Manipal, India
| | - Neetinkumar D Reddy
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal University Manipal, India
| | - H S Akhila
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal UniversityManipal, India; Department of Pharmacy Practice, Manipal College of Pharmaceutical Sciences, Manipal UniversityManipal, India
| | - Karthik Gourishetti
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal University Manipal, India
| | - Geetha Mathew
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal University Manipal, India
| | - Pawan G Nayak
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal University Manipal, India
| | - Nitesh Kumar
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal University Manipal, India
| | - Anoop Kishore
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal University Manipal, India
| | - Nampurath G Kutty
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal University Manipal, India
| | - Krishnadas Nandakumar
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal University Manipal, India
| | - Rekha R Shenoy
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal University Manipal, India
| | - Chamallamudi M Rao
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal University Manipal, India
| | - Alex Joseph
- Department of Pharmaceutical Chemistry, Manipal College of Pharmaceutical Sciences, Manipal University Manipal, India
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Röder PV, Wu B, Liu Y, Han W. Pancreatic regulation of glucose homeostasis. Exp Mol Med 2016; 48:e219. [PMID: 26964835 PMCID: PMC4892884 DOI: 10.1038/emm.2016.6] [Citation(s) in RCA: 454] [Impact Index Per Article: 56.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 12/03/2015] [Accepted: 12/06/2015] [Indexed: 12/11/2022] Open
Abstract
In order to ensure normal body function, the human body is dependent on a tight control of its blood glucose levels. This is accomplished by a highly sophisticated network of various hormones and neuropeptides released mainly from the brain, pancreas, liver, intestine as well as adipose and muscle tissue. Within this network, the pancreas represents a key player by secreting the blood sugar-lowering hormone insulin and its opponent glucagon. However, disturbances in the interplay of the hormones and peptides involved may lead to metabolic disorders such as type 2 diabetes mellitus (T2DM) whose prevalence, comorbidities and medical costs take on a dramatic scale. Therefore, it is of utmost importance to uncover and understand the mechanisms underlying the various interactions to improve existing anti-diabetic therapies and drugs on the one hand and to develop new therapeutic approaches on the other. This review summarizes the interplay of the pancreas with various other organs and tissues that maintain glucose homeostasis. Furthermore, anti-diabetic drugs and their impact on signaling pathways underlying the network will be discussed.
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Affiliation(s)
- Pia V Röder
- Metabolism in Human Diseases Unit, Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
- Metabolism in Human Diseases Unit, Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore 138673, Singapore. E-mail: or
| | - Bingbing Wu
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, A*STAR, Singapore, Singapore
| | - Yixian Liu
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, A*STAR, Singapore, Singapore
| | - Weiping Han
- Metabolism in Human Diseases Unit, Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, A*STAR, Singapore, Singapore
- Metabolism in Human Diseases Unit, Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore 138673, Singapore. E-mail: or
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24
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Roy V, Chenkual L, Gurusubramanian G. Mallotus roxburghianus modulates antioxidant responses in pancreas of diabetic rats. Acta Histochem 2016; 118:152-63. [PMID: 26764087 DOI: 10.1016/j.acthis.2015.12.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 12/15/2015] [Accepted: 12/17/2015] [Indexed: 12/20/2022]
Abstract
Mallotus roxburghianus has long been used by Mizo tribal people for the treatment of diabetes. Scientific validation at known doses may provide information about its safety and efficacy. Methanolic leaf extract of M. roxburghianus (MRME 100 and 400mg/kg) was tested in comparison with normal and alloxan diabetic rats for 28 days p.o. in terms of body and pancreatic weight, blood glucose level, antioxidant enzymes, expression of visfatin and PCNA, histopathology and histomorphometric measurements of pancreas. The results were evaluated statistically using ANOVA, correlation and regression and Principal component analysis (PCO). MRME (100 and 400mg/kg) treatment significantly (p<0.0001) decreased the body weight, blood glucose level, improved the mass and size of pancreas, elevated the levels of antioxidant enzymes and up regulate the expression of visfatin and PCNA. PCO analysis was good to fitness and prediction distinguishes the therapeutic effects of M. roxburghianus from the alloxan induced diabetic rats. MRME has significant role in protecting animals from alloxan-induced diabetic oxidative stress in pancreas and exhibited promising antihyperglycaemic and antioxidant activities along with significant reversal of disturbed antioxidant status and lipid peroxidative damage. Pancreatic architecture and physiology under diabetic oxidative stress have been significantly modulated by MRME and validated as a drug candidate for antidiabetic treatment. M. roxburghianus treatment restores the antioxidant enzyme system and rejuvenates the islets mass in alloxanized rat by accelerating visfatin and PCNA expression in pancreatic tissue.
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25
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Kaneto H, Matsuoka TA, Kimura T, Obata A, Shimoda M, Kamei S, Mune T, Kaku K. Appropriate therapy for type 2 diabetes mellitus in view of pancreatic β-cell glucose toxicity: "the earlier, the better". J Diabetes 2016. [PMID: 26223490 DOI: 10.1111/1753-0407.12331] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Pancreatic β-cells secrete insulin when blood glucose levels become high; however, when β-cells are chronically exposed to hyperglycemia, β-cell function gradually deteriorates, which is known as β-cell glucose toxicity. In the diabetic state, nuclear expression of the pancreatic transcription factors pancreatic and duodenal homeobox 1 (PDX-1) and v-Maf musculoaponeurotic fibrosarcoma oncogene family, protein A (MafA) is decreased. In addition, incretin receptor expression in β-cells is decreased, which is likely involved in the impairment of incretin effects in diabetes. Clinically, it is important to select appropriate therapy for type 2 diabetes mellitus (T2DM) so that β-cell function can be preserved. In addition, when appropriate pharmacological interventions against β-cell glucose toxicity are started at the early stages of diabetes, β-cell function is substantially restored, which is not observed if treatment is started at advanced stages. These observations indicate that it is likely that downregulation of pancreatic transcription factors and/or incretin receptors is involved in β-cell dysfunction observed in T2DM and it is very important to start appropriate pharmacological intervention against β-cell glucose toxicity in the early stages of diabetes.
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Affiliation(s)
- Hideaki Kaneto
- Department of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki
| | - Taka-Aki Matsuoka
- Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Tomohiko Kimura
- Department of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki
| | - Atsushi Obata
- Department of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki
| | - Masashi Shimoda
- Department of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki
| | - Shinji Kamei
- Department of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki
| | - Tomoatsu Mune
- Department of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki
| | - Kohei Kaku
- Department of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki
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26
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Okauchi S, Shimoda M, Obata A, Kimura T, Hirukawa H, Kohara K, Mune T, Kaku K, Kaneto H. Protective effects of SGLT2 inhibitor luseogliflozin on pancreatic β-cells in obese type 2 diabetic db/db mice. Biochem Biophys Res Commun 2016; 470:772-782. [DOI: 10.1016/j.bbrc.2015.10.109] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 10/20/2015] [Indexed: 02/06/2023]
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27
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Hirukawa H, Kaneto H, Shimoda M, Kimura T, Okauchi S, Obata A, Kohara K, Hamamoto S, Tawaramoto K, Hashiramoto M, Kaku K. Combination of DPP-4 inhibitor and PPARγ agonist exerts protective effects on pancreatic β-cells in diabetic db/db mice through the augmentation of IRS-2 expression. Mol Cell Endocrinol 2015; 413:49-60. [PMID: 26116826 DOI: 10.1016/j.mce.2015.06.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 06/05/2015] [Accepted: 06/07/2015] [Indexed: 11/29/2022]
Abstract
We investigated the effects of long- and short-term treatment with pioglitazone (Pio) and/or alogliptin (Alo) on β-cells in diabetic db/db mice. Six-week-old male db/db mice received Pio (25 mg/kg, oral) and/or Alo (30 mg/kg, oral) for 4 weeks and for 2 days. Blood glucose levels were decreased after 4-week intervention, but not after 2-day intervention. Pio increased adiponectin levels, and Alo decreased glucagon levels and increased active GlP-1 levels. Insulin sensitivity was restored by Pio. After 4-week treatment, β-cell mass was increased (over 2-fold increase) and expression levels of various β-cell-related factors were restored. Expression levels of IRS-2 and various downstream factors were up-regulated by Pio and Alo after 2-day and 4-week intervention. In addition, mRNA and protein levels of IRS-2 and various downstream factors were up-regulated in MIN6 cells after 24-h exposure to Pio and exendin-4. These results suggest that Pio and Alo additively up-regulate IRS-2 expression independently of the alteration of glycemic control. Taken together, combination of Pio and Alo exerts protective effects on β-cells in diabetic db/db mice, at least in part, through the augmentation of IRS-2 expression.
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Affiliation(s)
- Hidenori Hirukawa
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577 Matsushima, Kurashiki-city, Okayama 701-0192, Japan.
| | - Hideaki Kaneto
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577 Matsushima, Kurashiki-city, Okayama 701-0192, Japan
| | - Masashi Shimoda
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577 Matsushima, Kurashiki-city, Okayama 701-0192, Japan
| | - Tomohiko Kimura
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577 Matsushima, Kurashiki-city, Okayama 701-0192, Japan
| | - Seizo Okauchi
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577 Matsushima, Kurashiki-city, Okayama 701-0192, Japan
| | - Atsushi Obata
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577 Matsushima, Kurashiki-city, Okayama 701-0192, Japan
| | - Kenji Kohara
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577 Matsushima, Kurashiki-city, Okayama 701-0192, Japan
| | - Sumiko Hamamoto
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577 Matsushima, Kurashiki-city, Okayama 701-0192, Japan
| | - Kazuhito Tawaramoto
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577 Matsushima, Kurashiki-city, Okayama 701-0192, Japan
| | - Mitsuru Hashiramoto
- Division of Diabetes and Endocrinology, Yodogawa Christian Hospital, Osaka, Japan
| | - Kohei Kaku
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577 Matsushima, Kurashiki-city, Okayama 701-0192, Japan; Department of General Internal Medicine 1, Kawasaki Hospital, Kawasaki Medical School, Okayama, Japan
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28
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Murad HAS, Saleh HA, Abdulaziz GS, Abdulsattar MA, Ali SS. Effect of metformin and pioglitazone on β-catenin and biochemical markers in sitagliptin-induced pancreatitis in diabetic rats. Int J Diabetes Dev Ctries 2015. [DOI: 10.1007/s13410-014-0278-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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29
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Chen L, So WY, Li SYT, Cheng Q, Boucher BJ, Leung PS. Niacin-induced hyperglycemia is partially mediated via niacin receptor GPR109a in pancreatic islets. Mol Cell Endocrinol 2015; 404:56-66. [PMID: 25622782 DOI: 10.1016/j.mce.2015.01.029] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Revised: 01/20/2015] [Accepted: 01/20/2015] [Indexed: 12/17/2022]
Abstract
The widely used lipid-lowering drug niacin is reported to induce hyperglycemia during chronic and high-dose treatments, but the mechanism is poorly understood. Recently, the niacin receptor [G-protein-coupled receptor, (GPR) 109a], has been localized to islet cells while its potential role therein remains unclear. We, therefore, aimed at investigating how GPR109a regulates islet beta-cell function and its downstream signaling using high-fat diet-induced obese mice and INS-1E beta cells. Eight-week niacin treatment elevated blood glucose concentration in obese mice with increased areas under the curve at oral glucose and intraperitoneal insulin tolerance tests. Additionally, niacin treatment significantly decreased glucose-stimulated insulin secretion (GSIS) but induced peroxisome proliferator-activated receptor gamma (Pparg) and GPR109a expression in isolated pancreatic islets; concomitantly, reactive oxygen species (ROS) were transiently increased, with decreases in GSIS, intracellular cyclic adenosine monophosphate (cAMP) accumulation and mitochondrial membrane potential (ΔΨm), but with increased expression of uncoupling protein 2 (Ucp2), Pparg and Gpr109a in INS-1E cells. Corroborating these findings, the decreases in GSIS, ΔΨm and cAMP production and increases in ROS, Pparg and GPR109a expression were abolished in INS-1E cells by GPR109a knockdown. Our data indicate that niacin-induced pancreatic islet dysfunction is probably modulated through activation of the islet beta-cell GPR109a-induced ROS-PPARγ-UCP2 pathways.
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Affiliation(s)
- Lihua Chen
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Wing Yan So
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Stephen Y T Li
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Qianni Cheng
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Barbara J Boucher
- Centre for Diabetes, The Blizard Institute, Queen Mary University of London, London, UK
| | - Po Sing Leung
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China.
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30
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Kimura T, Kaneto H, Shimoda M, Hirukawa H, Okauchi S, Kohara K, Hamamoto S, Tawaramoto K, Hashiramoto M, Kaku K. Protective effects of pioglitazone and/or liraglutide on pancreatic β-cells in db/db mice: Comparison of their effects between in an early and advanced stage of diabetes. Mol Cell Endocrinol 2015; 400:78-89. [PMID: 25463759 DOI: 10.1016/j.mce.2014.11.018] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2014] [Revised: 11/14/2014] [Accepted: 11/20/2014] [Indexed: 12/24/2022]
Abstract
The aim was to compare the protective effects of pioglitazone (PIO) and/or liraglutide (LIRA) on β-cells with the progression of diabetes. Male db/db mice were treated with PIO and/or LIRA for 2 weeks in an early and advanced stage. In an early stage insulin biosynthesis and secretion were markedly increased by PIO and LIRA which was not observed in an advanced stage. In concomitant with such phenomena, expression levels of various β-cell-related factors were up-regulated by PIO and LIRA only in an early stage. Furthermore, β-cell mass was also increased by the treatment only in an early stage. Although there was no difference in apoptosis ratio between the two stages, β-cell proliferation was augmented by the treatment only in an early stage. In conclusion, protective effects of pioglitazone and/or liraglutide on β-cells were more powerful in an early stage of diabetes compared to an advanced stage.
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MESH Headings
- Animals
- Apoptosis/drug effects
- Blood Glucose/metabolism
- Caspases/genetics
- Caspases/metabolism
- Cell Proliferation/drug effects
- Diabetes Mellitus, Type 2/drug therapy
- Diabetes Mellitus, Type 2/genetics
- Diabetes Mellitus, Type 2/metabolism
- Diabetes Mellitus, Type 2/pathology
- Disease Models, Animal
- Disease Progression
- Gene Expression/drug effects
- Glucagon/blood
- Glucagon-Like Peptide 1/analogs & derivatives
- Glucagon-Like Peptide 1/pharmacology
- Hypoglycemic Agents/pharmacology
- Insulin/blood
- Insulin-Secreting Cells/drug effects
- Insulin-Secreting Cells/metabolism
- Insulin-Secreting Cells/pathology
- Ki-67 Antigen/genetics
- Ki-67 Antigen/metabolism
- Liraglutide
- Male
- Mice
- Mice, Transgenic
- Organ Size/drug effects
- Pioglitazone
- Proto-Oncogene Proteins c-bcl-2/genetics
- Proto-Oncogene Proteins c-bcl-2/metabolism
- RNA, Ribosomal, 18S/genetics
- RNA, Ribosomal, 18S/metabolism
- Thiazolidinediones/pharmacology
- Time Factors
- Triglycerides/blood
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Affiliation(s)
- Tomohiko Kimura
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577 Matsushima, Kurashiki-city, Okayama 701-0192, Japan.
| | - Hideaki Kaneto
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577 Matsushima, Kurashiki-city, Okayama 701-0192, Japan
| | - Masashi Shimoda
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577 Matsushima, Kurashiki-city, Okayama 701-0192, Japan
| | - Hidenori Hirukawa
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577 Matsushima, Kurashiki-city, Okayama 701-0192, Japan
| | - Seizo Okauchi
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577 Matsushima, Kurashiki-city, Okayama 701-0192, Japan
| | - Kenji Kohara
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577 Matsushima, Kurashiki-city, Okayama 701-0192, Japan
| | - Sumiko Hamamoto
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577 Matsushima, Kurashiki-city, Okayama 701-0192, Japan
| | - Kazuhito Tawaramoto
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577 Matsushima, Kurashiki-city, Okayama 701-0192, Japan
| | - Mitsuru Hashiramoto
- Division of Diabetes and Endocrinology, Yodogawa Christian Hospital, 1-7-50 Shibajima, Osaka-city, Osaka 533-0024, Japan
| | - Kohei Kaku
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, 577 Matsushima, Kurashiki-city, Okayama 701-0192, Japan; Department of General Internal Medicine 1, Kawasaki Hospital, Kawasaki Medical School, 2-1-80 Nakasange, Okayama-city, Okayama 700-8505, Japan
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Kanda Y, Hashiramoto M, Shimoda M, Hamamoto S, Tawaramoto K, Kimura T, Hirukawa H, Nakashima K, Kaku K. Dietary restriction preserves the mass and function of pancreatic β cells via cell kinetic regulation and suppression of oxidative/ER stress in diabetic mice. J Nutr Biochem 2014; 26:219-26. [PMID: 25488546 DOI: 10.1016/j.jnutbio.2014.10.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 09/15/2014] [Accepted: 10/08/2014] [Indexed: 01/09/2023]
Abstract
To assess the molecular mechanisms by which dietary restriction preserves the β-cell mass and function in diabetic db/db mice. Male db/db mice were divided into two groups with or without diet restriction. Daily food intake of db/db mice was adjusted to that of the control db/m mice, which was determined in advance. A dietary restriction was implemented for 6 weeks from 6 weeks of age. Islet morphology, β-cell function and gene expression profiles specific for pancreatic islet cells were compared. Food intake in db/m mice was 50% of that in db/db mice. Impaired glucose tolerance and insulin sensitivity were significantly ameliorated in db/db mice with dietary restriction. The pancreatic β-cell mass was greater in mice with dietary restriction than that in mice without intervention. The dietary restriction significantly increased cyclin D gene expression and down-regulated CAD gene expression at 12 weeks compared with untreated db/db mice. Antiapoptotic bcl-2 gene expression was significantly increased, whereas genes related to oxidative stress, ER stress and inflammatory processes, such as NADPH oxidase, CHOP10 and TNF, were markedly down-regulated in mice with dietary restriction. Dietary restriction preserved the pancreatic β-cell function and β-cell mass in diabetic db/db mice, suggesting that alimentary therapy prevented β-cell loss by suppressing cellular apoptosis and antioxidative stress in the pancreatic β cells.
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Affiliation(s)
- Yukiko Kanda
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki, Japan.
| | - Mitsuru Hashiramoto
- Division of Diabetes and Endocrinology, Yodogawa Christian Hospital, Osaka, Japan
| | - Masashi Shimoda
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki, Japan
| | - Sumiko Hamamoto
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki, Japan
| | - Kazuhito Tawaramoto
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki, Japan
| | - Tomohiko Kimura
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki, Japan
| | - Hidenori Hirukawa
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki, Japan
| | - Koji Nakashima
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki, Japan
| | - Kohei Kaku
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki, Japan
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Hogh KLN, Craig MN, Uy CE, Nygren H, Asadi A, Speck M, Fraser JD, Rudecki AP, Baker RK, Orešič M, Gray SL. Overexpression of PPARγ specifically in pancreatic β-cells exacerbates obesity-induced glucose intolerance, reduces β-cell mass, and alters islet lipid metabolism in male mice. Endocrinology 2014; 155:3843-52. [PMID: 25051434 DOI: 10.1210/en.2014-1076] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The contribution of peroxisomal proliferator-activated receptor (PPAR)-γ agonism in pancreatic β-cells to the antidiabetic actions of thiazolidinediones has not been clearly elucidated. Genetic models of pancreatic β-cell PPARγ ablation have revealed a potential role for PPARγ in β-cell expansion in obesity but a limited role in normal β-cell physiology. Here we overexpressed PPARγ1 or PPARγ2 specifically in pancreatic β-cells of mice subjected to high-fat feeding using an associated adenovirus (β-PPARγ1-HFD and β-PPARγ2-HFD mice). We show β-cell-specific PPARγ1 or PPARγ2 overexpression in diet-induced obese mice exacerbated obesity-induced glucose intolerance with decreased β-cell mass, increased islet cell apoptosis, and decreased plasma insulin compared with obese control mice (β-eGFP-HFD mice). Analysis of islet lipid composition in β-PPARγ2-HFD mice revealed no significant changes in islet triglyceride content and an increase in only one of eight ceramide species measured. Interestingly β-PPARγ2-HFD islets had significantly lower levels of lysophosphatidylcholines, lipid species shown to enhance insulin secretion in β-cells. Gene expression profiling revealed increased expression of uncoupling protein 2 and genes involved in fatty acid transport and β-oxidation. In summary, transgenic overexpression of PPARγ in β-cells in diet-induced obesity negatively impacts whole-animal carbohydrate metabolism associated with altered islet lipid content, increased expression of β-oxidative genes, and reduced β-cell mass.
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Affiliation(s)
- K-Lynn N Hogh
- Northern Medical Program (K.N.H., M.N.C., C.E.U., J.D.F., A.P.R., S.L.G.), University of Northern British Columbia, Prince George, British Columbia, Canada V2N 4Z9; Department of Cellular and Physiological Sciences and Faculty of Medicine (A.A., R.K.B.), University of British Columbia, Vancouver, British Columbia, Canada V5Z 4H4; VTT Technical Research Centre of Finland (H.N., M.O.), Espoo FI-02044, Finland; Steno Diabetes Center A/S (H.N., M.O.), Gentofte, Denmark; and Child and Family Research Institute (M.S.), Vancouver, British Columbia, Canada V6T 1Z1
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Ahangarpour A, Zamaneh HT, Jabari A, Nia HM, Heidari H. Antidiabetic and hypolipidemic effects of Dorema aucheri hydroalcoholic leave extract in streptozotocin-nicotinamide induced type 2 diabetes in male rats. IRANIAN JOURNAL OF BASIC MEDICAL SCIENCES 2014; 17:808-14. [PMID: 25729552 PMCID: PMC4340991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Accepted: 02/09/2014] [Indexed: 11/06/2022]
Abstract
OBJECTIVES The present study investigated the antidiabetic and hypolipidemic properties of Dorema aucheri leave hydroalcoholic extract in nicotinamide-streptozotocin induced type 2 diabetic rats. MATERIALS AND METHODS nicotinamide/streptozotocin-induced diabetic rats were supplemented orally with three different doses of D. aucheri (100, 200 and 400 mg/kg BW) or glibenclamide (0.25 mg/kg) for 4 weeks. Ultimately, blood of animals has taken and glucose, insulin, lipid profiles, SGPT, alkaline phosphatase, SGOT, leptin levels were assayed. RESULTS D. aucheri has highly significant blood glucose lowering effect. Administration of the extract to diabetic rats resulted in a remarkable change in serum lipid profiles, insulin and leptin levels relative to diabetic group. Also the extract reversed back the serum levels of SGPT, alkaline phosphatase and SGOT to near normal in treated diabetic rats. CONCLUSION D. aucheri could be useful in treatment of diabetes. Moderate dose of D. aucheri (200 mg/kg) was more effective than the others.
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Affiliation(s)
- Akram Ahangarpour
- Health Research institute, Diabetes Research Center, Dept of Physiology, Faculty of Medical Sciences, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | | | - Ayob Jabari
- Department of Biology, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, Iran
| | - Hamid Malekshahi Nia
- Department of sport physiology, Faculty of physical education and sport science, Shahid Chamran University of Ahvaz, Ahvaz, Iran
| | - Hamid Heidari
- Department of Physiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences. Ahvaz, Iran and Department of Physiology, Faculty of Medical Sciences, Qom University of Medical Sciences, Qom, Iran,Corresponding author: Hamid Heidari, Department of Physiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences. Ahvaz, Iran and Department of Physiology, Faculty of Medical Sciences, Qom University of Medical Sciences, Qom, Iran.
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Hayashi H, Yamada R, Das SS, Sato T, Takahashi A, Hiratsuka M, Hirasawa N. Glucagon-like peptide-1 production in the GLUTag cell line is impaired by free fatty acids via endoplasmic reticulum stress. Metabolism 2014; 63:800-11. [PMID: 24680601 DOI: 10.1016/j.metabol.2014.02.012] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Revised: 02/15/2014] [Accepted: 02/17/2014] [Indexed: 12/16/2022]
Abstract
OBJECTS Glucagon-like peptide-1 (GLP-1) is secreted from intestinal L cells, enhances glucose-stimulated insulin secretion, and protects pancreas beta cells. However, few studies have examined hypernutrition stress in L cells and its effects on their function. Here, we demonstrated that a high-fat diet reduced glucose-stimulated secretion of GLP-1 and induced expression of an endoplasmic reticulum (ER) stress markers in the intestine of a diet-induced obesity mouse model. METHODS To clarify whether ER stress in L cells caused the attenuation of GLP-1 secretion, we treated the mouse intestinal L cell line, GLUTag cells with palmitate or oleate. RESULTS Palmitate, but not oleate caused ER stress and decreased the protein levels of prohormone convertase 1/3 (PC1/3), an essential enzyme in GLP-1 production. The same phenomena were observed in GLUTag cells treated with in ER stress inducer, thapsigargin. Moreover, oleate improved palmitate-induced ER stress, reduced protein and activity levels of PC1/3, and attenuated GLP-1 secretion from GLUTag cells. CONCLUSIONS/INTERPRETATION These results suggest that the intake of abundant saturated fatty acids induces ER stress in the intestine and decreases GLP-1 production.
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Affiliation(s)
- Hiroto Hayashi
- Laboratory of Pharmacotherapy of Life-Style Related Diseases, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Ren Yamada
- Laboratory of Pharmacotherapy of Life-Style Related Diseases, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Siddhartha Shankar Das
- Laboratory of Pharmacotherapy of Life-Style Related Diseases, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Taiki Sato
- Laboratory of Pharmacotherapy of Life-Style Related Diseases, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Aki Takahashi
- Laboratory of Pharmacotherapy of Life-Style Related Diseases, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Masahiro Hiratsuka
- Laboratory of Pharmacotherapy of Life-Style Related Diseases, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, Japan
| | - Noriyasu Hirasawa
- Laboratory of Pharmacotherapy of Life-Style Related Diseases, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, Japan.
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Pathak V, Vasu S, Flatt PR, Irwin N. Effects of chronic exposure of clonal β-cells to elevated glucose and free fatty acids on incretin receptor gene expression and secretory responses to GIP and GLP-1. Diabetes Obes Metab 2014; 16:357-65. [PMID: 24164718 DOI: 10.1111/dom.12227] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Revised: 10/03/2013] [Accepted: 10/21/2013] [Indexed: 12/11/2022]
Abstract
AIM The incretin effect, mediated by glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1), is impaired in type 2 diabetes. METHODS This study examines the effects of prolonged exposure to elevated glucose and free fatty acids in clonal BRIN BD11 cells on GIP and GLP-1 action. RESULTS Glucotoxic conditions (18 h) had no effect on GIP- or GLP-1-mediated insulinotropic responses. In contrast, 48 h glucotoxic culture impaired (p < 0.05 to p < 0.001) insulin release in response to GLP-1, and particularly GIP. Culture under lipotoxic conditions (18 h) impaired (p < 0.05 to p < 0.001) the insulin-releasing effect of GIP, but was without effect on GLP-1. However, 48 h lipotoxic culture compromised both GIP (p < 0.05 to p < 0.001) and GLP-1 (p < 0.05 to p < 0.01) insulin-releasing actions. Glucolipotoxic culture (18 h) completely annulled the insulinotropic action of GIP, whereas GLP-1 effects were similar to control. However, when glucolipotoxic culture was extended to 48 h, both GIP- and GLP-1-mediated effects were (p < 0.05 to p < 0.001) impaired. Assessment of cell viability, number and insulin content revealed detrimental (p < 0.05 to p < 0.001) effects under all culture conditions, barring 18 h glucotoxic and lipotoxic culture. Finally, GIP-R gene and protein expression was increased (p < 0.05 to p < 0.01) under glucotoxic culture, with decreased (p < 0.05 to p < 0.001) expression following glucolipotoxic culture. GLP-1-R gene expression followed a similar trend, but protein levels were generally reduced under all culture conditions. CONCLUSION The results indicate that impaired insulinotropic response to GIP and GLP-1 under diabetic milieu involves mechanisms beyond simple expression of respective receptors.
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Affiliation(s)
- V Pathak
- SAAD Centre for Pharmacy Diabetes, University of Ulster, Coleraine, UK
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Novelli M, Canistro D, Martano M, Funel N, Sapone A, Melega S, Masini M, De Tata V, Pippa A, Vecoli C, Campani D, De Siena R, Soleti A, Paolini M, Masiello P. Anti-diabetic properties of a non-conventional radical scavenger, as compared to pioglitazone and exendin-4, in streptozotocin-nicotinamide diabetic mice. Eur J Pharmacol 2014; 729:37-44. [PMID: 24530416 DOI: 10.1016/j.ejphar.2014.01.071] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2013] [Revised: 01/22/2014] [Accepted: 01/24/2014] [Indexed: 12/13/2022]
Abstract
We previously showed that the innovative radical scavenger bis(1-hydroxy-2,2,6,6-tetramethyl-4-piperidinyl)-decandioate (IAC) improves metabolic dysfunctions in a diabetic mouse model. Here, we compared the in vivo effects of IAC with those of the anti-diabetic drugs pioglitazone (PIO) and exendin-4 (EX-4). Diabetes was induced in C57Bl/6J mice by streptozotocin and nicotinamide administration. Paralleled by healthy controls, diabetic animals (D) were randomly assigned to four groups and treated daily for 7 consecutive weeks: D+saline, ip; D+IAC 30mg/kgb.w., ip; D+PIO 10mg/kgb.w. per os; and D+EX-4, 50μg/kgb.w., ip. Our results show that IAC reduced basal hyperglycemia and improved glucose tolerance better than PIO or EX-4. Interestingly, in the heart of diabetic mice, IAC treatment normalized the increased levels of GSSG/GSH ratio and thiobarbituric acid reactive substances, indexes of oxidative stress and damage, while PIO and EX-4 were less effective. As supported by immunohistochemical data, IAC markedly prevented diabetic islet β-cell reduced density, differently from PIO and EX-4 that had only a moderate effect. Interestingly, in diabetic animals, IAC treatment enhanced the activity of pancreatic-duodenal homeobox 1 (PDX-1), an oxidative stress-sensitive transcription factor essential for maintenance of β-cell function, as evaluated by quantification of its nuclear immunostaining, whereas PIO or EX-4 treatments did not. Altogether, these observations support the improvement of the general redox balance and β-cell function induced by IAC treatment in streptozotocin-nicotinamide diabetic mice. Furthermore, in this model, the correction of diabetic alterations was better obtained by treatment with the radical scavenger IAC than with pioglitazone or exendin-4.
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Affiliation(s)
- Michela Novelli
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma 55, 56126 Pisa, Italy
| | - Donatella Canistro
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy
| | | | - Niccola Funel
- Department of Surgical, Medical, Molecular, and Critical Area Pathology, University of Pisa, Via Savi 10, 56126 Pisa, Italy
| | - Andrea Sapone
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy
| | - Simone Melega
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy
| | - Matilde Masini
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma 55, 56126 Pisa, Italy
| | - Vincenzo De Tata
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma 55, 56126 Pisa, Italy
| | - Anna Pippa
- Institute of Clinical Physiology, CNR, Via Moruzzi 1, 56124 Pisa, Italy
| | - Cecilia Vecoli
- Institute of Clinical Physiology, CNR, Via Moruzzi 1, 56124 Pisa, Italy
| | - Daniela Campani
- Department of Surgical, Medical, Molecular, and Critical Area Pathology, University of Pisa, Via Savi 10, 56126 Pisa, Italy
| | | | | | - Moreno Paolini
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum, University of Bologna, Via Irnerio 48, 40126 Bologna, Italy
| | - Pellegrino Masiello
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma 55, 56126 Pisa, Italy.
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Deng R, Nie A, Jian F, Liu Y, Tang H, Zhang J, Zhang Y, Shao L, Li F, Zhou L, Wang X, Ning G. Acute exposure of beta-cells to troglitazone decreases insulin hypersecretion via activating AMPK. Biochim Biophys Acta Gen Subj 2014; 1840:577-85. [DOI: 10.1016/j.bbagen.2013.10.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2013] [Revised: 10/05/2013] [Accepted: 10/13/2013] [Indexed: 11/16/2022]
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Yang SC, Tseng HL, Shieh KR. Circadian-clock system in mouse liver affected by insulin resistance. Chronobiol Int 2013; 30:796-810. [DOI: 10.3109/07420528.2013.766204] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Lee JO, Auger C, Park DH, Kang M, Oak MH, Kim KR, Schini-Kerth VB. An ethanolic extract of Lindera obtusiloba stems, YJP-14, improves endothelial dysfunction, metabolic parameters and physical performance in diabetic db/db mice. PLoS One 2013; 8:e65227. [PMID: 23755196 PMCID: PMC3670856 DOI: 10.1371/journal.pone.0065227] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Accepted: 04/24/2013] [Indexed: 01/08/2023] Open
Abstract
Lindera obtusiloba is a medicinal herb traditionally used in Asia for improvement of blood circulation, treatment of inflammation, and prevention of liver damage. A previous study has shown that an ethanolic extract of Lindera obtusiloba stems (LOE) has vasoprotective and antihypertensive effects. The possibility that Lindera obtusiloba improves endothelial function and metabolic parameters in type 2 diabetes mellitus (T2DM) remains to be examined. Therefore, the aim of the present study was to determine the potential of LOE to prevent the development of an endothelial dysfunction, and improve metabolic parameters including hyperglycemia, albuminuria and physical exercise capacity in db/db mice, an experimental model of T2DM. The effect of LOE (100 mg/kg/day by gavage for 8 weeks) on these parameters was compared to that of an oral antidiabetic drug, pioglitazone (30 mg/kg/day by gavage). Reduced blood glucose level, body weight and albumin-creatinine ratio were observed in the group receiving LOE compared to the control db/db group. The LOE treatment improved endothelium-dependent relaxations, abolished endothelium-dependent contractions to acetylcholine in the aorta, and normalized the increased vascular oxidative stress and expression of NADPH oxidase, cyclooxygenases, angiotensin II, angiotensin type 1 receptors and peroxynitrite and the decreased expression of endothelial NO synthase in db/db mice. The angiotensin-converting enzyme (ACE) activity was reduced in the LOE group compared to that in the control db/db group. LOE also inhibited the activity of purified ACE, COX-1 and COX-2 in a dose-dependent manner. In addition, LOE improved physical exercise capacity. Thus, the present findings indicate that LOE has a beneficial effect on the vascular system in db/db mice by improving endothelium-dependent relaxations and vascular oxidative stress most likely by normalizing the angiotensin system, and also on metabolic parameters, and these effects are associated with an enhanced physical exercise capacity.
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MESH Headings
- Albuminuria/prevention & control
- Angiotensin II/genetics
- Angiotensin II/metabolism
- Animals
- Aorta/drug effects
- Aorta/physiopathology
- Blood Glucose/metabolism
- Body Weight/drug effects
- Diabetes Mellitus, Type 2/drug therapy
- Diabetes Mellitus, Type 2/metabolism
- Diabetes Mellitus, Type 2/physiopathology
- Disease Models, Animal
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Ethanol/chemistry
- Exercise Tolerance/drug effects
- Gene Expression/drug effects
- Humans
- Hyperglycemia/prevention & control
- Hypoglycemic Agents/pharmacology
- Lindera/chemistry
- Male
- Mice
- Mice, Transgenic
- NADPH Oxidases/genetics
- NADPH Oxidases/metabolism
- Nitric Oxide Synthase Type III/genetics
- Nitric Oxide Synthase Type III/metabolism
- Pioglitazone
- Plant Extracts/pharmacology
- Prostaglandin-Endoperoxide Synthases/genetics
- Prostaglandin-Endoperoxide Synthases/metabolism
- Receptor, Angiotensin, Type 1/genetics
- Receptor, Angiotensin, Type 1/metabolism
- Thiazolidinediones/pharmacology
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Affiliation(s)
- Jung-Ok Lee
- UMR CNRS 7213, Laboratoire de Biophotonique et Pharmacologie, Faculté de Pharmacie, Université de Strasbourg, Illkirch, France
- Research and Development Center, Hanwha Pharma. Co., Ltd., Chuncheon, Republic of Korea
| | - Cyril Auger
- UMR CNRS 7213, Laboratoire de Biophotonique et Pharmacologie, Faculté de Pharmacie, Université de Strasbourg, Illkirch, France
| | - Dong Hyun Park
- Research Center, YangJi Chemicals, Suwon, Republic of Korea
| | - Moonkyu Kang
- Research and Development Center, Hanwha Pharma. Co., Ltd., Chuncheon, Republic of Korea
| | - Min-Ho Oak
- College of Pharmacy, Mokpo National University, Muan, Jeonam, Republic of Korea
| | - Kyoung Rak Kim
- Research and Development Center, Hanwha Pharma. Co., Ltd., Chuncheon, Republic of Korea
| | - Valérie B. Schini-Kerth
- UMR CNRS 7213, Laboratoire de Biophotonique et Pharmacologie, Faculté de Pharmacie, Université de Strasbourg, Illkirch, France
- * E-mail:
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40
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Kalanderian A, Abate N, Patrikeev I, Wei J, Vincent KL, Motamedi M, Saade GR, Bytautiene E. Pioglitazone therapy in mouse offspring exposed to maternal obesity. Am J Obstet Gynecol 2013; 208:308.e1-7. [PMID: 23313309 DOI: 10.1016/j.ajog.2013.01.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Revised: 12/07/2012] [Accepted: 01/09/2013] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Pioglitazone (PIO), an antidiabetic drug of the thiazolidinedione family, improves glucose and lipid metabolism in muscle, adipose, and liver tissues via peroxisome proliferator-activated receptor gamma activation. We hypothesize that PIO therapy will improve the metabolic status of offspring exposed to maternal obesity in a mouse model developmentally programmed for metabolic syndrome. STUDY DESIGN CD-1 female mice were fed a high-fat diet for 3 months prior to breeding and throughout pregnancy and lactation. The pups were weaned to a standard-fat diet. Offspring were randomly assigned to receive 40 mg/kg of PIO in 0.5% of methyl cellulose or 0.5% methyl cellulose by daily oral gavage for 2 weeks. The pre- and posttreatment total body weights of the pups were recorded. Visceral and subcutaneous adipose tissue were evaluated using microcomputed tomography. Serum analytes were measured. After treatment, minimally invasive microendoscopic fluorescence confocal imaging and intraperitoneal glucose tolerance tests were performed. The data were analyzed using appropriate statistical tests (significance, P < .05). RESULTS PIO therapy resulted in lower total body weight and lower visceral adipose tissue gain and increased subcutaneous adipose tissue. PIO significantly lowered triglycerides, insulin levels, and homeostasis model assessment of insulin resistance in males and fasting glucose in females. There was a trend toward larger adipocyte size. CONCLUSION Short-term PIO therapy in the offspring of obese mothers attenuates metabolic changes associated with the developmental programming of metabolic syndrome. These novel data suggest a potential role for drugs that activate peroxisome proliferator-activated receptor gamma receptors to prevent metabolic syndrome in the adult offspring at risk to develop metabolic alterations.
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Hamamoto S, Kanda Y, Shimoda M, Tatsumi F, Kohara K, Tawaramoto K, Hashiramoto M, Kaku K. Vildagliptin preserves the mass and function of pancreatic β cells via the developmental regulation and suppression of oxidative and endoplasmic reticulum stress in a mouse model of diabetes. Diabetes Obes Metab 2013; 15:153-63. [PMID: 22950702 PMCID: PMC3558804 DOI: 10.1111/dom.12005] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Revised: 06/26/2012] [Accepted: 09/02/2012] [Indexed: 01/10/2023]
Abstract
AIM We investigated the molecular mechanisms by which vildagliptin preserved pancreatic β cell mass and function. METHODS Morphological, biochemical and gene expression profiles of the pancreatic islets were investigated in male KK-A(y) -TaJcl(KK-A(y) ) and C57BL/6JJcl (B6) mice aged 8 weeks which received either vildagliptin or a vehicle for 4 weeks. RESULTS Body weight, food intake, fasting blood glucose, plasma insulin and active glucagon-like peptide-1 were unchanged with vildagliptin treatment in both mice. In KK-A(y) mice treated with vildagliptin, increased plasma triglyceride (TG) level and islet TG content were decreased, insulin sensitivity significantly improved, and the glucose tolerance ameliorated with increases in plasma insulin levels. Furthermore, vildagliptin increased glucose-stimulated insulin secretion, islet insulin content and pancreatic β cell mass in both strains. By vildagliptin, the expression of genes involved in cell differentiation/proliferation was upregulated in both strains, those related to apoptosis, endoplasmic reticulum stress and lipid synthesis was decreased and those related to anti-apoptosis and anti-oxidative stress was upregulated, in KK-A(y) mice. The morphological results were consistent with the gene expression profiles. CONCLUSION Vildagliptin increases β cell mass by not only directly affecting cell kinetics but also by indirectly reducing cell apoptosis, oxidative stress and endoplasmic reticulum stress in diabetic mice.
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Affiliation(s)
- S Hamamoto
- Division of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Kurashiki, Japan
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42
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Lamounier RN, Coimbra CN, White P, Costal FL, Oliveira LS, Giannella-Neto D, Kaestner KH, Corrêa-Giannella ML. Apoptosis rate and transcriptional response of pancreatic islets exposed to the PPAR gamma agonist Pioglitazone. Diabetol Metab Syndr 2013; 5:1. [PMID: 23298687 PMCID: PMC3598339 DOI: 10.1186/1758-5996-5-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Accepted: 12/06/2012] [Indexed: 01/09/2023] Open
Abstract
To explore the molecular pathways underlying thiazolidinediones effects on pancreatic islets in conditions mimicking normo- and hyperglycemia, apoptosis rate and transcriptional response to Pioglitazone at both physiological and supraphysiological glucose concentrations were evaluated. Adult rat islets were cultured at physiological (5.6 mM) and supraphysiological (23 mM) glucose concentrations in presence of 10 μM Pioglitazone or vehicle. RNA expression profiling was evaluated with the PancChip 13k cDNA microarray after 24-h, and expression results for some selected genes were validated by qRT-PCR. The effects of Pioglitazone were investigated regarding apoptosis rate after 24-, 48- and 72-h. At 5.6 mM glucose, 101 genes were modulated by Pioglitazone, while 1,235 genes were affected at 23 mM glucose. Gene networks related to lipid metabolism were identified as altered by Pioglitazone at both glucose concentrations. At 23 mM glucose, cell cycle and cell death pathways were significantly regulated as well. At 5.6 mM glucose, Pioglitazone elicited a transient reduction in islets apoptosis rate while at 23 mM, Bcl2 expression was reduced and apoptosis rate was increased by Pioglitazone. Our data demonstrate that the effect of Pioglitazone on gene expression profile and apoptosis rate depends on the glucose concentration. The modulation of genes related to cell death and the increased apoptosis rate observed at supraphysiological glucose concentration raise concerns about Pioglitazone's direct effects in conditions of hyperglycemia and reinforce the necessity of additional studies designed to evaluate TZDs effects on the preservation of β-cell function in situations where glucotoxicity might be more relevant than lipotoxicity.
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Affiliation(s)
- Rodrigo N Lamounier
- Laboratory for Cellular and Molecular Endocrinology LIM-25, University of Sao Paulo Medical School, Av. Dr. Arnaldo 455 #4305, 01246-903, São Paulo, Brazil
- Department of Genetics and Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania School of Medicine, 752B CRB 415 Curie Blvd., 19104, Philadelphia, Pennsylvania, USA
| | - Cassio N Coimbra
- Laboratory for Cellular and Molecular Endocrinology LIM-25, University of Sao Paulo Medical School, Av. Dr. Arnaldo 455 #4305, 01246-903, São Paulo, Brazil
- Laboratory Medicine, University of Santo Amaro, Sao Paulo, Brazil
| | - Peter White
- Department of Genetics and Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania School of Medicine, 752B CRB 415 Curie Blvd., 19104, Philadelphia, Pennsylvania, USA
| | - Flavia L Costal
- Laboratory for Cellular and Molecular Endocrinology LIM-25, University of Sao Paulo Medical School, Av. Dr. Arnaldo 455 #4305, 01246-903, São Paulo, Brazil
| | - Leonardo S Oliveira
- Laboratory for Cellular and Molecular Endocrinology LIM-25, University of Sao Paulo Medical School, Av. Dr. Arnaldo 455 #4305, 01246-903, São Paulo, Brazil
- Laboratory Medicine, University of Santo Amaro, Sao Paulo, Brazil
| | - Daniel Giannella-Neto
- Postgraduate Program in Medicine, Universidade Nove de Julho - Uninove, Sao Paulo, Brazil
| | - Klaus H Kaestner
- Department of Genetics and Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania School of Medicine, 752B CRB 415 Curie Blvd., 19104, Philadelphia, Pennsylvania, USA
| | - Maria Lúcia Corrêa-Giannella
- Laboratory for Cellular and Molecular Endocrinology LIM-25, University of Sao Paulo Medical School, Av. Dr. Arnaldo 455 #4305, 01246-903, São Paulo, Brazil
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Welters HJ, El Ouaamari A, Kawamori D, Meyer J, Hu J, Smith DM, Kulkarni RN. Rosiglitazone promotes PPARγ-dependent and -independent alterations in gene expression in mouse islets. Endocrinology 2012; 153:4593-9. [PMID: 22807489 PMCID: PMC3512010 DOI: 10.1210/en.2012-1243] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The glitazone class of insulin-sensitizing agents act, in part, by the activation of peroxisome proliferator-activated receptor (PPAR)-γ in adipocytes. However, it is unclear whether the expression of PPARγ in the islets is essential for their potential β-cell-sparing properties. To investigate the in vivo effects of rosiglitazone on β-cell biology, we used an inducible, pancreatic and duodenal homeobox-1 enhancer element-driven, Cre recombinase to knockout PPARγ expression specifically in adult β-cells (PPARgKO). Subjecting the PPARgKO mice to a chow diet led to virtually undetectable changes in glucose or insulin sensitivity, which was paralleled by minimal changes in islet gene expression. Similarly, challenging the mutant mice with a high-fat diet and treatment with rosiglitazone did not alter insulin sensitivity, glucose-stimulated insulin secretion, islet size, or proliferation in the knockout mice despite PPARγ-dependent and -independent changes in islet gene expression. These data suggest that PPARγ expression in the β-cells is unlikely to be directly essential for normal β-cell function or the insulin-sensitizing actions of rosiglitazone.
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Affiliation(s)
- Hannah J Welters
- Peninsula College of Medicine and Dentistry, University of Exeter, Exeter EX2 5DW, United Kingdom.
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Düfer M, Noack K, Edalat A, Krippeit-Drews P, Drews G. Glitazones exert multiple effects on β-cell stimulus-secretion coupling. Mol Pharmacol 2012; 83:51-60. [PMID: 23024191 DOI: 10.1124/mol.112.081638] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Earlier studies suggest that glitazones exert beneficial effects in patients with type 2 diabetes by directly affecting insulin secretion of β-cells, besides improving the effectiveness of insulin in peripheral tissues. The effects of glitazones on stimulus-secretion coupling (SSC) are poorly understood. We tested the influence of troglitazone and pioglitazone on different parameters of SSC, including insulin secretion (radioimmunoassay), cell membrane potential, various ion currents (patch-clamp), mitochondrial membrane potential (ΔΨ), and cytosolic Ca(2+) concentration (fluorescence). Troglitazone exerted stimulatory, inhibitory, or no effects on insulin secretion depending on the drug and glucose concentration. It depolarized the ΔΨ, thus lowering ATP production, which resulted in opening of ATP-dependent K(+) channels (K(ATP) channels) and reduced insulin secretion. However, it also exerted direct inhibitory effects on K(ATP) channels that can explain enhanced insulin secretion. Troglitazone also inhibited the currents through voltage-dependent Ca(2+) and K(+) channels. Pioglitazone was less effective than troglitazone on all parameters tested. The effects of both glitazones were markedly reduced in the presence of bovine serum albumin. Glitazones exert multiple actions on β-cell SSC that have to be considered as undesired side effects because the influence of these compounds on β-cells is not controllable. The final effect on insulin secretion depends on many parameters, including the actual glucose and drug concentration, protein binding of the drug, and the drug by itself. Troglitazone and pioglitazone differ in their influence on SSC. It can be assumed that the effects of pioglitazone on β-cells are negligible under in vivo conditions.
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Affiliation(s)
- Martina Düfer
- Institute of Pharmacy, Department of Pharmacology, University of Tübingen, Auf der Morgenstelle 8, D-72076 Tübingen, Germany
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McIntosh B, Cameron C, Singh SR, Yu C, Dolovich L, Houlden R. Choice of therapy in patients with type 2 diabetes inadequately controlled with metformin and a sulphonylurea: a systematic review and mixed-treatment comparison meta-analysis. OPEN MEDICINE : A PEER-REVIEWED, INDEPENDENT, OPEN-ACCESS JOURNAL 2012; 6:e62-74. [PMID: 23696771 PMCID: PMC3659216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Revised: 08/11/2011] [Accepted: 08/15/2011] [Indexed: 11/26/2022]
Abstract
BACKGROUND Metformin and a sulphonylurea are often used in combination for the treatment of type 2 diabetes mellitus. We conducted a systematic review and meta-analysis to evaluate the comparative safety and efficacy of all available classes of antihyperglycemic therapies in patients with type 2 diabetes inadequately controlled with metformin and sulphonylurea combination therapy. METHODS MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE, BIOSIS Previews, PubMed and the Cochrane Central Register of Controlled Trials were searched for randomized controlled trials published in English from 1980 to November 2009. Additional citations were obtained from the grey literature and conference proceedings and through stakeholder feedback. Two reviewers independently selected the studies, extracted the data and assessed risk of bias. Key outcomes of interest were hemoglobin A1c, body weight, hypoglycemia, patients' satisfaction with treatment, quality of life, long-term diabetes-related complications, withdrawals due to adverse events, serious adverse events and mortality. Mixed-treatment comparison meta-analyses were conducted to calculate mean differences between drug classes for changes in hemoglobin A1c and body weight. When appropriate, pairwise meta-analyses were used to estimate differences for other outcomes. RESULTS We identified 33 randomized controlled trials meeting the inclusion criteria. The methodologic quality of the studies was generally poor. Insulins (basal, biphasic, bolus), dipeptidyl peptidase-4 (DPP-4) inhibitors, glucagon-like peptide-1 (GLP-1) analogues and thiazolidinediones (TZDs) all produced statistically significant reductions in hemoglobin A1c in combination with metformin and a sulphonylurea (-0.89% to -1.17%), whereas meglitinides and alpha-glucosidase inhibitors did not. Biphasic insulin, bolus insulin, and TZDs were associated with weight gain (1.85-5.00 kg), whereas DPP-4 inhibitors and alpha-glucosidase inhibitors were weight-neutral, and GLP-1 analogues were associated with modest weight loss. Treatment regimens containing insulin were associated with increased hypoglycemia relative to comparators, but severe hypoglycemia was rare across all treatments. INTERPRETATION Third-line agents for the treatment of type 2 diabetes are similar in terms of glycemic control but differ in their propensity to cause weight gain and hypoglycemia. Longer-term studies with larger sample sizes are required to determine if any of the drug classes are superior with regard to reducing diabetes-related complications.
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Affiliation(s)
- Brendan McIntosh
- Canadian Agency for Drugs and Technologies in Health (CADTH), Ottawa, Ontario, Canada
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Puddu A, Sanguineti R, Durante A, Viviani GL. Pioglitazone attenuates the detrimental effects of advanced glycation end-products in the pancreatic beta cell line HIT-T15. ACTA ACUST UNITED AC 2012; 177:79-84. [PMID: 22587907 DOI: 10.1016/j.regpep.2012.05.089] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Revised: 02/07/2012] [Accepted: 05/05/2012] [Indexed: 11/24/2022]
Abstract
Pioglitazone is an anti-diabetic agent that preserves pancreatic beta cell mass and improves their function. Advanced Glycation End-Products (AGEs) are implicated in diabetic complications. We previously demonstrated that exposure of the pancreatic islet cell line HIT-T15 to high concentrations of AGEs significantly decreases cell proliferation and insulin secretion, and affects transcription factors regulating insulin gene transcription. The aim of this work was to investigate the effects of Pioglitazone on the function and viability of HIT-T15 cells cultured with AGEs. HIT-T15 cells were cultured for 5 days in the presence of AGEs alone, or supplemented with 1 μmol/l Pioglitazone. Cell viability, insulin secretion and insulin content, redox balance, expression of the AGE receptor (RAGE), and NF-kB activation were then determined. The results showed that Pioglitazone protected beta cells against AGEs-induced apoptosis and necrosis. Moreover, Pioglitazone restored the redox balance and improved the responsiveness to low glucose concentration. Adding Pioglitazone to the AGEs culture attenuated NF-kB phosphorylation, and prevented AGEs to down-regulate IkBα expression. These findings suggest that Pioglitazone protects beta cells from the dangerous effects of AGEs.
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Affiliation(s)
- A Puddu
- University of Genova, Department of Internal Medicine and Medical Specialties, Viale Benedetto XV, 6, 16132 Genova, Italy.
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Shimoda M, Kanda Y, Hamamoto S, Tawaramoto K, Hashiramoto M, Matsuki M, Kaku K. The human glucagon-like peptide-1 analogue liraglutide preserves pancreatic beta cells via regulation of cell kinetics and suppression of oxidative and endoplasmic reticulum stress in a mouse model of diabetes. Diabetologia 2011; 54:1098-108. [PMID: 21340625 PMCID: PMC3071950 DOI: 10.1007/s00125-011-2069-9] [Citation(s) in RCA: 121] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2010] [Accepted: 12/22/2010] [Indexed: 01/09/2023]
Abstract
AIMS/HYPOTHESIS We investigated the molecular mechanism by which the human glucagon-like peptide-1 analogue liraglutide preserves pancreatic beta cells in diabetic db/db mice. METHODS Male db/db and m/m mice aged 10 weeks received liraglutide or vehicle for 2 days or 2 weeks. In addition to morphological and biochemical analysis of pancreatic islets, gene expression profiles in the islet core area were investigated by laser capture microdissection and real-time RT-PCR. RESULTS Liraglutide treatment for 2 weeks improved metabolic variables and insulin sensitivity in db/db mice. Liraglutide also increased glucose-stimulated insulin secretion (GSIS) and islet insulin content in both mouse strains and reduced triacylglycerol content in db/db mice. Expression of genes involved in cell differentiation and proliferation in both mouse strains was regulated by liraglutide, which, in db/db mice, downregulated genes involved in pro-apoptosis, endoplasmic reticulum (ER) stress and lipid synthesis, and upregulated genes related to anti-apoptosis and anti-oxidative stress. In the 2 day experiment, liraglutide slightly improved metabolic variables in db/db mice, but GSIS, insulin and triacylglycerol content were not affected. In db/db mice, liraglutide increased gene expression associated with cell differentiation, proliferation and anti-apoptosis, and suppressed gene expression involved in pro-apoptosis; it had no effect on genes related to oxidative stress or ER stress. Morphometric results for cell proliferation, cell apoptosis and oxidative stress in db/db mice islets were consistent with the results of the gene expression analysis. CONCLUSIONS/INTERPRETATION Liraglutide increases beta cell mass not only by directly regulating cell kinetics, but also by suppressing oxidative and ER stress, secondary to amelioration of glucolipotoxicity.
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Affiliation(s)
- M. Shimoda
- Division of Diabetes, Endocrinology and Metabolism, Department of Internal Medicine, Kawasaki Medical School, 577 Matsushima, Kurashiki, Okayama, 701-0192 Japan
| | - Y. Kanda
- Division of Diabetes, Endocrinology and Metabolism, Department of Internal Medicine, Kawasaki Medical School, 577 Matsushima, Kurashiki, Okayama, 701-0192 Japan
| | - S. Hamamoto
- Division of Diabetes, Endocrinology and Metabolism, Department of Internal Medicine, Kawasaki Medical School, 577 Matsushima, Kurashiki, Okayama, 701-0192 Japan
| | - K. Tawaramoto
- Division of Diabetes, Endocrinology and Metabolism, Department of Internal Medicine, Kawasaki Medical School, 577 Matsushima, Kurashiki, Okayama, 701-0192 Japan
| | - M. Hashiramoto
- Division of Diabetes, Endocrinology and Metabolism, Department of Internal Medicine, Kawasaki Medical School, 577 Matsushima, Kurashiki, Okayama, 701-0192 Japan
| | - M. Matsuki
- Division of Diabetes, Endocrinology and Metabolism, Department of Internal Medicine, Kawasaki Medical School, 577 Matsushima, Kurashiki, Okayama, 701-0192 Japan
| | - K. Kaku
- Division of Diabetes, Endocrinology and Metabolism, Department of Internal Medicine, Kawasaki Medical School, 577 Matsushima, Kurashiki, Okayama, 701-0192 Japan
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Park SY, Sohn UD. Inhibitory effect of rosiglitazone on the acid-induced intracellular generation of hydrogen peroxide in cultured feline esophageal epithelial cells. Naunyn Schmiedebergs Arch Pharmacol 2011; 383:191-201. [PMID: 21212935 DOI: 10.1007/s00210-010-0594-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2010] [Accepted: 12/19/2010] [Indexed: 01/28/2023]
Abstract
Peroxisome proliferator-activated receptor-gamma (PPARγ) agonists have been reported to enhance antioxidant defenses by increasing levels of catalase and copper-zinc superoxide dismutase (Cu/Zn SOD) in oligodendrocyte progenitor cells. In this study, we investigated the effects of the PPARγ agonist, rosiglitazone, on hydrogen peroxide (H(2)O(2)) generation by acidified medium at pH 5.5 (AM5.5), which is in the pH range of duodenogastric refluxates, in primary cultured feline esophageal epithelial cells (EEC). Successful isolation of EEC was identified by immunocytochemistry. AM5.5- and rosiglitazone-induced cell viabilities were determined using 3-(4,5-dimethylthiozol-2-yl)-2,5-diphenyltetrazolium bromide assays. The NAD(P)H oxidase activity was measured, and expression of catalase or SOD protein by AM5.5 in the absence and presence of rosiglitazone was assessed using western blotting analysis. PPARγ protein and mRNA were constitutively expressed in EEC. In the incubation with rosiglitazone alone, cell viability was shown more than 90% at 0-10 μM for 72 h. After exposure to AM5.5 for 8 h, intracellular H(2)O(2) was significantly generated. Treatment with rosiglitazone prior to and during exposure to AM5.5 inhibited the H(2)O(2) generation whereas the specific PPARγ antagonist GW9662 offsets the inhibitory action of rosiglitazone. H(2)O(2) generation was also prevented by a nonspecific ROS scavenger N-acetylcysteine or an inhibitor of NADPH oxidase diphenyleneiodonium. The enhanced AM5.5-induced NAD(P)H oxidase activity was not suppressed by rosiglitazone. Instead, the pretreatment of rosiglitazone enhanced the protein expression of catalase, Cu/Zn SOD, and Mn SOD, which are endogenous antioxidative enzymes. These findings indicate that rosiglitazone inhibits AM5.5-induced intracellular H(2)O(2) production, which occurs via NAD(P)H oxidase activation, by using a PPARγ-dependent pathway, and that the underlying mechanism involves an increase in the expression of catalase and SOD proteins.
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Affiliation(s)
- Sun Young Park
- Department of Pharmacology, College of Pharmacy, Chung-Ang University, Seoul, 156-756, Republic of Korea
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Gupta D, Kono T, Evans-Molina C. The role of peroxisome proliferator-activated receptor γ in pancreatic β cell function and survival: therapeutic implications for the treatment of type 2 diabetes mellitus. Diabetes Obes Metab 2010; 12:1036-47. [PMID: 20977574 PMCID: PMC3764483 DOI: 10.1111/j.1463-1326.2010.01299.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The pathogenesis of type 2 diabetes mellitus involves both peripheral insulin resistance and dysfunctional insulin secretion from the pancreatic β cell. Currently, there is intense research focus on delineating the etiologies of pancreatic β cell dysfunction in type 2 diabetes. However, there remains an unmet clinical need to establish therapeutic guidelines and strategies that emphasize the preservation of pancreatic β cell function in at-risk and affected individuals. Thiazolidinediones are orally active agents approved for use in type 2 diabetes and act as agonists of the nuclear hormone receptor PPAR-γ. These drugs improve insulin sensitivity, but there is also a growing appreciation of PPAR-γ actions within the β cell. PPAR-γ has been shown to regulate directly key β cell genes involved in glucose sensing, insulin secretion and insulin gene transcription. Further, pharmacologic PPAR-γ activation has been shown to protect against glucose-, lipid-, cytokine- and islet amyloid polypeptide (IAPP)-induced activation of numerous stress pathways. This article will review the mechanisms by which PPAR-γ activation acts to maintain β cell function and survival in type 2 diabetes mellitus and highlight some of the current controversies in this field.
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Affiliation(s)
- D Gupta
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN 46202, USA
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