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Neuroprotective Effects of the DPP4 Inhibitor Vildagliptin in In Vivo and In Vitro Models of Parkinson's Disease. Int J Mol Sci 2022; 23:ijms23042388. [PMID: 35216503 PMCID: PMC8877991 DOI: 10.3390/ijms23042388] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 02/16/2022] [Accepted: 02/19/2022] [Indexed: 12/25/2022] Open
Abstract
Parkinson’s disease (PD) is characterized by loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc) of the midbrain. Restoration of nigrostriatal dopamine neurons has been proposed as a potential therapeutic strategy for PD. Because currently used PD therapeutics only help relieve motor symptoms and do not treat the cause of the disease, highly effective drugs are needed. Vildagliptin, a dipeptidyl peptidase 4 (DPP4) inhibitor, is an anti-diabetic drug with various pharmacological properties including neuroprotective effects. However, the detailed effects of vildagliptin against PD are not fully understood. We investigated the effects of vildagliptin on PD and its underlying molecular mechanisms using a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model and a 1-methyl-4-phenylpyridium (MPP+)-induced cytotoxicity model. Vildagliptin (50 mg/kg) administration significantly attenuated MPTP-induced motor deficits as evidenced by rotarod, pole, and nest building tests. Immunohistochemistry and Western blot analysis revealed that vildagliptin increased tyrosine hydroxylase-positive cells in the SNpc and striatum, which was reduced by MPTP treatment. Furthermore, vildagliptin activated MPTP-decreased PI3k/Akt and mitigated MPTP-increased ERK and JNK signaling pathways in the striatum. Consistent with signaling transduction in the mouse striatum, vildagliptin reversed MPP+-induced dephosphorylation of PI3K/Akt and phosphorylation of ERK and JNK in SH-SY5Y cells. Moreover, vildagliptin attenuated MPP+-induced conversion of LC3B-II in SH-SY5Y cells, suggesting its role in autophagy inhibition. Taken together, these findings indicate that vildagliptin has protective effects against MPTP-induced motor dysfunction by inhibiting dopaminergic neuronal apoptosis, which is associated with regulation of PI3k/Akt, ERK, and JNK signaling transduction. Our findings suggest vildagliptin as a promising repurposing drug to treat PD.
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Liu S, Chang X, Yu J, Xu W. Cerasus humilis Cherry Polyphenol Reduces High-Fat Diet-Induced Obesity in C57BL/6 Mice by Mitigating Fat Deposition, Inflammation, and Oxidation. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:4424-4436. [PMID: 32227855 DOI: 10.1021/acs.jafc.0c01617] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
This study aimed to determine the anti-obesity effects and mechanisms of Cerasus humilis polyphenol (CHP) in C57BL/6 obese mice and 3T3-L1 cells. High-performance liquid chromatography-electrospray ionization-tandem mass spectrometry was used for the qualitative and quantitative identification of CHP components. The obese mice, induced by feeding high-fat diet (HFD), were treated with CHP (250 mg/kg/day) by gavage for 12 weeks. Orlistat was gavaged at 15.6 mg/kg bw/day, as a positive control group. The analysis revealed that the main components of CHP were procyanidin B2, cyanidin-3-glucoside, and pelargonidin-3-glucoside. CHP dietary supplementation significantly reduced body weight and improved blood lipid measurements in HFD-fed mice (p < 0.01). Moreover, it inhibited mRNA expression of miR-122, Srebp-1c, and Cpt1a (p < 0.01) and reduced hepatic lipid deposition, as seen by hematoxylin and eosin staining. CHP downregulated the protein expression of PPARγ and C/EBPα in HFD-induced obese mice and inhibited adipocyte differentiation (p < 0.01). Compared with the HFD group, CHP supplementation had an obvious anti-inflammatory effect (decreased protein expression, such as TNF-α, IL-6, and MCP1), reducing leptin levels and TNF-α secretion in serum and cells (p < 0.01). CHP significantly inhibited the expression of miR-27a/b (53.3 and 29.9%, p < 0.01) in mice retroperitoneal white adipocytes, enhancing the expression of the target gene Prdm16 and significantly upregulating Sirt1 (105.5%, p < 0.01) compared with the HFD group. Moreover, CHP supplementation effectively improved oxidative stress (ROS, T-AOC, SOD, CAT, and GSH-Px) induced by HFD in obese mice (p < 0.01). Thus, CHP mitigates adipocyte differentiation, browning of white adipocytes, and reduction of inflammation and antioxidant activity to reduce obesity. Consequently, these results provide novel insights into the anti-obesity roles of CHP in HFD-induced obesity.
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Affiliation(s)
- Suwen Liu
- College of Food Science & Technology, Hebei Normal University of Science and Technology, Qinhuangdao, Hebei 066004, China
| | - Xuedong Chang
- College of Food Science & Technology, Hebei Normal University of Science and Technology, Qinhuangdao, Hebei 066004, China
- Hebei Yanshan Special Industrial Technology Research Institute, Qinhuangdao, Hebei 066004, China
| | - Jincheng Yu
- College of Food Science & Technology, Hebei Normal University of Science and Technology, Qinhuangdao, Hebei 066004, China
| | - Weifeng Xu
- College of Food Science & Technology, Hebei Normal University of Science and Technology, Qinhuangdao, Hebei 066004, China
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Kitao N, Nakamura A, Miyoshi H, Nomoto H, Takahashi K, Omori K, Yamamoto K, Cho KY, Terauchi Y, Atsumi T. The role of glucokinase and insulin receptor substrate-2 in the proliferation of pancreatic beta cells induced by short-term high-fat diet feeding in mice. Metabolism 2018; 85:48-58. [PMID: 29544862 DOI: 10.1016/j.metabol.2018.03.010] [Citation(s) in RCA: 8] [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: 11/10/2017] [Revised: 02/20/2018] [Accepted: 03/08/2018] [Indexed: 12/11/2022]
Abstract
OBJECTIVE We investigated whether glucokinase and insulin receptor substrate-2 were required for beta cell proliferation induced by short-term high-fat (HF) diet feeding, as has been shown for long-term HF diet. METHODS Eight-week-old C57BL/6J mice were exposed to either a standard chow (SC) or HF diet. After 1 week on the diet, histopathological beta cell proliferation and gene expression in isolated islets were examined. Additionally, 8-week-old beta cell-specific glucokinase haploinsufficient (Gck+/-) and Irs2 knockout (Irs2-/-) mice were exposed to either an SC or HF diet. RESULTS Immunohistochemical analysis revealed that short-term HF diet feeding resulted in a significant increase in BrdU incorporation rate compared with SC consumption in wild-type mice. Western blot analysis demonstrated that Irs2 expression levels did not differ between the two diets. Moreover, there was a significant increase in the BrdU incorporation rate in the HF diet group compared with the SC group in both Gck+/- and Irs2-/- mice. Gene expression profiling of isolated islets from mice fed an HF diet for 1 week revealed that the expression levels of downstream genes of Foxm1 were coordinately upregulated. One week of HF diet feeding stimulated beta cell proliferation with Foxm1 upregulation in 48-week-old mice as well as in 8-week-old. CONCLUSIONS The mechanism of pancreatic beta cell proliferation induced by short-term HF diet feeding in mice could involve a glucokinase- and Irs2-independent pathway. Our results suggest that the pathways that induce beta cell proliferation in response to short-term HF diet feeding may differ from those in response to sustained HF diet feeding.
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Affiliation(s)
- Naoyuki Kitao
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Akinobu Nakamura
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
| | - Hideaki Miyoshi
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Hiroshi Nomoto
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Kiyohiko Takahashi
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Kazuno Omori
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Kohei Yamamoto
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Kyu Yong Cho
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Yasuo Terauchi
- Department of Endocrinology and Metabolism, Graduate School of Medicine, Yokohama City University, Japan
| | - Tatsuya Atsumi
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
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Takahashi K, Nakamura A, Miyoshi H, Nomoto H, Kitao N, Omori K, Yamamoto K, Cho KY, Terauchi Y, Atsumi T. Effect of the sodium-glucose cotransporter 2 inhibitor luseogliflozin on pancreatic beta cell mass in db/db mice of different ages. Sci Rep 2018; 8:6864. [PMID: 29717223 PMCID: PMC5931598 DOI: 10.1038/s41598-018-25126-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 04/13/2018] [Indexed: 01/09/2023] Open
Abstract
To examine the effects of luseogliflozin, a sodium-glucose cotransporter 2 inhibitor, on pancreatic beta cell mass in db/db mice of different ages. db/db mice aged 6, 10, 14 and 24 weeks old were fed either standard chow (control group) or standard chow containing 0.01% luseogliflozin (luseo group). After 4 weeks, immunohistochemistry and gene expression tests were conducted. In 6-week-old db/db mice, immunohistochemistry revealed a significant increase in beta cell mass in the luseo group compared with the control group after 4 weeks of treatment. Gene expression profiling of isolated islets showed upregulation Mafa, Pdx1, Ki67 and Ccnd2 in the luseo group. Beta cell mass decreased with age in db/db mice in the control group. Beta cell mass in the luseo group significantly increased compared with the control group regardless of age, although beta cell mass in the 28-week-old luseo group (4 weeks of treatment in 24-week-old db/db mice) was significantly lower than in the 10-week-old luseo group (4 weeks of treatment in 6-week-old db/db mice). Luseogliflozin preserved beta cell mass in db/db mice. The protective effect was more evident in the earlier phase of diabetes.
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Affiliation(s)
- Kiyohiko Takahashi
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Akinobu Nakamura
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan.
| | - Hideaki Miyoshi
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Hiroshi Nomoto
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Naoyuki Kitao
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Kazuno Omori
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Kohei Yamamoto
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Kyu Yong Cho
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Yasuo Terauchi
- Department of Endocrinology and Metabolism, Graduate School of Medicine, Yokohama City University, Yokohama, Japan
| | - Tatsuya Atsumi
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
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Abdelsalam RM, Safar MM. Neuroprotective effects of vildagliptin in rat rotenone Parkinson's disease model: role of RAGE-NFκB and Nrf2-antioxidant signaling pathways. J Neurochem 2015; 133:700-7. [DOI: 10.1111/jnc.13087] [Citation(s) in RCA: 132] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Revised: 02/25/2015] [Accepted: 03/02/2015] [Indexed: 12/20/2022]
Affiliation(s)
- Rania M. Abdelsalam
- Faculty of Pharmacy; Department of Pharmacology and Toxicology; Cairo University; Cairo Egypt
| | - Marwa M. Safar
- Faculty of Pharmacy; Department of Pharmacology and Toxicology; Cairo University; Cairo Egypt
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Wu YJ, Guo X, Li CJ, Li DQ, Zhang J, Yang Y, Kong Y, Guo H, Liu DM, Chen LM. Dipeptidyl peptidase-4 inhibitor, vildagliptin, inhibits pancreatic beta cell apoptosis in association with its effects suppressing endoplasmic reticulum stress in db/db mice. Metabolism 2015; 64:226-35. [PMID: 25195070 DOI: 10.1016/j.metabol.2014.08.006] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Revised: 07/17/2014] [Accepted: 08/12/2014] [Indexed: 12/11/2022]
Abstract
AIMS Vildagliptin promotes beta cell survival by inhibiting cell apoptosis. It has been suggested that chronic ER (endoplasmic reticulum) stress triggers beta cell apoptosis. The objective of the study is to explore whether the pro-survival effect of vildagliptin is associated with attenuation of endoplasmic reticulum stress in islets of db/db mice. METHODS Vildagliptin was orally administered to db/db mice for 6 weeks, followed by evaluation of beta cell apoptosis by caspase3 activity and TUNEL staining method. Endoplasmic reticulum stress markers were determined with quantitative RT-PCR, immunohistochemistry and immunoblot analysis. RESULTS After 6 weeks of treatment, vildagliptin treatment increased plasma active GLP-1 levels (22.63±1.19 vs. 11.69±0.44, P<0.001), inhibited beta cell apoptosis as demonstrated by lower amounts of TUNEL staining nuclei (0.37±0.03 vs. 0.55±0.03, P<0.01) as well as decreased caspase3 activity (1.48±0.11 vs. 2.67±0.13, P<0.01) in islets of diabetic mice compared with untreated diabetic group. Further, vildagliptin treatment down-regulated several genes related to endoplasmic reticulum stress including TRIB3 (tribbles homolog 3) (15.9±0.4 vs. 33.3±1.7, ×10⁻³, P<0.001), ATF-4(activating transcription factor 4) (0.83±0.06 vs. 1.42±0.02, P<0.001) and CHOP(C/EBP homologous protein) (0.07±0.01 vs. 0.16±0.01, P<0.001). CONCLUSIONS Vildagliptin promoted beta cell survival in db/db mice in association with down-regulating markers of endoplasmic reticulum stress including TRIB3, ATF-4 as well as CHOP.
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Affiliation(s)
- Yan-ju Wu
- Key Laboratory of Hormones and Development (Ministry of Health), Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin Medical University, Tianjin, China
| | - Xin Guo
- Key Laboratory of Hormones and Development (Ministry of Health), Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin Medical University, Tianjin, China
| | - Chun-jun Li
- Key Laboratory of Hormones and Development (Ministry of Health), Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin Medical University, Tianjin, China
| | - Dai-qing Li
- Key Laboratory of Hormones and Development (Ministry of Health), Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin Medical University, Tianjin, China
| | - Jie Zhang
- Key Laboratory of Hormones and Development (Ministry of Health), Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin Medical University, Tianjin, China
| | - Yiping Yang
- Key Laboratory of Hormones and Development (Ministry of Health), Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin Medical University, Tianjin, China
| | - Yan Kong
- Key Laboratory of Hormones and Development (Ministry of Health), Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin Medical University, Tianjin, China
| | - Hang Guo
- Key Laboratory of Hormones and Development (Ministry of Health), Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin Medical University, Tianjin, China
| | - De-min Liu
- Key Laboratory of Hormones and Development (Ministry of Health), Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin Medical University, Tianjin, China
| | - Li-ming Chen
- Key Laboratory of Hormones and Development (Ministry of Health), Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin Medical University, Tianjin, China.
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Kim MJ, Choi OK, Chae KS, Lee H, Chung SS, Ham DS, Kim JW, Yoon KH, Park KS, Jung HS. Autophagy deficiency in β cells blunts incretin-induced suppression of glucagon release from α cells. Islets 2015; 7:e1129096. [PMID: 26744903 PMCID: PMC4878271 DOI: 10.1080/19382014.2015.1129096] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Incretin-based therapy such as GLP-1 receptor agonists and DPP-4 inhibitors for type 2 diabetes mellitus is characterized by glucose-dependent insulin secretion and glucose-inhibited glucagon secretion. Recently, autophagy deficiency in islet β cells has been shown to contribute to the pathogenesis of type 2 diabetes mellitus however, with the role of incretin has not been established. To evaluate the role of autophagy in incretin effects, 8-week-old male β cell-specific Atg7 knockout (Atg7(Δβ cell)) mice and wild-type mice were administered vildagliptin for 12 weeks. Vildagliptin treatment improved glucose intolerance and hypoinsulinemia; however, it failed to suppress serum glucagon levels after glucose loading in the Atg7(Δβ cell) mice. Ex vivo glucose-induced glucagon suppression was also blunted in the islets from vildagliptin-treated Atg7(Δβ cell) mice. The α cell mass was not affected by β cell autophagy deficiency or vildagliptin. However, glucagon mRNA expression was significantly increased by vildagliptin in the autophagy-deficient islets, and was significantly reduced by vildagliptin in wild-type islets. Pancreatic glucagon contents were not in agreement with the changes in mRNA expression, suggesting a dysregulation in glucagon translation and secretion. In vitro studies revealed that glucose-stimulated cAMP production was impaired in the autophagy-deficient islets exposed to exendin-4. Taken together, the results suggest that the constitutive autophagy in β cells could regulate incretin-induced glucagon expression and release in α cells, and that cAMP may play a role in this process.
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Affiliation(s)
- Min Joo Kim
- Department of Internal Medicine; Seoul National University College of Medicine; Seoul, Republic of Korea
- Department of Internal Medicine; Korea Cancer Center Hospital; Seoul, Republic of Korea
| | - Ok Kyong Choi
- Innovative Research Institute for Cell Therapy; Seoul, Republic of Korea
| | - Kyung Sil Chae
- Innovative Research Institute for Cell Therapy; Seoul, Republic of Korea
| | - Hakmo Lee
- Innovative Research Institute for Cell Therapy; Seoul, Republic of Korea
| | - Sung Soo Chung
- Innovative Research Institute for Cell Therapy; Seoul, Republic of Korea
| | - Dong-Sik Ham
- Department of Endocrinology and Metabolism; The Catholic University of Korea; Seoul, Republic of Korea
| | - Ji-Won Kim
- Department of Endocrinology and Metabolism; The Catholic University of Korea; Seoul, Republic of Korea
| | - Kun-Ho Yoon
- Department of Endocrinology and Metabolism; The Catholic University of Korea; Seoul, Republic of Korea
| | - Kyong Soo Park
- Department of Internal Medicine; Seoul National University College of Medicine; Seoul, Republic of Korea
- Innovative Research Institute for Cell Therapy; Seoul, Republic of Korea
| | - Hye Seung Jung
- Department of Internal Medicine; Seoul National University College of Medicine; Seoul, Republic of Korea
- Innovative Research Institute for Cell Therapy; Seoul, Republic of Korea
- Correspondence to: Hye Seung Jung;
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Oliveira JM, Rebuffat SA, Gasa R, Gomis R. Targeting type 2 diabetes: lessons from a knockout model of insulin receptor substrate 2. Can J Physiol Pharmacol 2014; 92:613-20. [DOI: 10.1139/cjpp-2014-0114] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Insulin receptor substrate 2 (IRS2) is a widely expressed protein that regulates crucial biological processes including glucose metabolism, protein synthesis, and cell survival. IRS2 is part of the insulin – insulin-like growth factor (IGF) signaling pathway and mediates the activation of the phosphotidylinositol 3-kinase (PI3K)–Akt and the Ras–mitogen-activated protein kinase (MAPK) cascades in insulin target tissues and in the pancreas. The best evidence of this is that systemic elimination of the Irs2 in mice (Irs2−/−) recapitulates the pathogenesis of type 2 diabetes (T2D), in that diabetes arises as a consequence of combined insulin resistance and beta-cell failure. Indeed, work using this knockout mouse has confirmed the importance of IRS2 in the control of glucose homeostasis and especially in the survival and function of pancreatic beta-cells. These studies have shown that IRS2 is critically required for beta-cell compensation in conditions of increased insulin demand. Importantly, islets isolated from T2D patients exhibit reduced IRS2 expression, which supports the likely contribution of altered IRS2-dependent signaling to beta-cell failure in human T2D. For all these reasons, the Irs2−/− mouse has been and will be essential for elucidating the inter-relationship between beta-cell function and insulin resistance, as well as to delineate therapeutic strategies to protect beta-cells during T2D progression.
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Affiliation(s)
- Joana Moitinho Oliveira
- Diabetes and Obesity Research Laboratory, Institut d’Investigations Biomediques August Pi i Sunyer, Centre Esther Koplowitz, C/Rosselló, 149-153 08036 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas, Barcelona, Spain
| | - Sandra A. Rebuffat
- Diabetes and Obesity Research Laboratory, Institut d’Investigations Biomediques August Pi i Sunyer, Centre Esther Koplowitz, C/Rosselló, 149-153 08036 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas, Barcelona, Spain
| | - Rosa Gasa
- Diabetes and Obesity Research Laboratory, Institut d’Investigations Biomediques August Pi i Sunyer, Centre Esther Koplowitz, C/Rosselló, 149-153 08036 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas, Barcelona, Spain
| | - Ramon Gomis
- Diabetes and Obesity Research Laboratory, Institut d’Investigations Biomediques August Pi i Sunyer, Centre Esther Koplowitz, C/Rosselló, 149-153 08036 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas, Barcelona, Spain
- University of Barcelona, Hospital Clínic, Barcelona, Spain
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Lamont BJ, Andrikopoulos S. Hope and fear for new classes of type 2 diabetes drugs: is there preclinical evidence that incretin-based therapies alter pancreatic morphology? J Endocrinol 2014; 221:T43-61. [PMID: 24424288 DOI: 10.1530/joe-13-0577] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Incretin-based therapies appear to offer many advantages over other approaches for treating type 2 diabetes. Some preclinical studies have suggested that chronic activation of glucagon-like peptide 1 receptor (GLP1R) signalling in the pancreas may result in the proliferation of islet β-cells and an increase in β-cell mass. This provided hope that enhancing GLP1 action could potentially alter the natural progression of type 2 diabetes. However, to date, there has been no evidence from clinical trials suggesting that GLP1R agonists or dipeptidyl peptidase-4 (DPP4) inhibitors can increase β-cell mass. Nevertheless, while the proliferative capacity of these agents remains controversial, some studies have raised concerns that they could potentially contribute to the development of pancreatitis and hence increase the risk of pancreatic cancer. Currently, there are very limited clinical data to directly assess these potential benefits and risks of incretin-based therapies. However, a review of the preclinical studies indicates that incretin-based therapies probably have only a limited capacity to regenerate pancreatic β-cells, but may be useful for preserving any remaining β-cells in type 2 diabetes. In addition, the majority of preclinical evidence does not support the notion that GLP1R agonists or DPP4 inhibitors cause pancreatitis.
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Affiliation(s)
- Benjamin J Lamont
- Department of Medicine (Austin Health), The University of Melbourne, Melbourne, Victoria, Australia
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Cersosimo E, Solis-Herrera C, Trautmann ME, Malloy J, Triplitt CL. Assessment of pancreatic β-cell function: review of methods and clinical applications. Curr Diabetes Rev 2014; 10:2-42. [PMID: 24524730 PMCID: PMC3982570 DOI: 10.2174/1573399810666140214093600] [Citation(s) in RCA: 164] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Revised: 12/02/2013] [Accepted: 12/03/2013] [Indexed: 12/19/2022]
Abstract
Type 2 diabetes mellitus (T2DM) is characterized by a progressive failure of pancreatic β-cell function (BCF) with insulin resistance. Once insulin over-secretion can no longer compensate for the degree of insulin resistance, hyperglycemia becomes clinically significant and deterioration of residual β-cell reserve accelerates. This pathophysiology has important therapeutic implications. Ideally, therapy should address the underlying pathology and should be started early along the spectrum of decreasing glucose tolerance in order to prevent or slow β-cell failure and reverse insulin resistance. The development of an optimal treatment strategy for each patient requires accurate diagnostic tools for evaluating the underlying state of glucose tolerance. This review focuses on the most widely used methods for measuring BCF within the context of insulin resistance and includes examples of their use in prediabetes and T2DM, with an emphasis on the most recent therapeutic options (dipeptidyl peptidase-4 inhibitors and glucagon-like peptide-1 receptor agonists). Methods of BCF measurement include the homeostasis model assessment (HOMA); oral glucose tolerance tests, intravenous glucose tolerance tests (IVGTT), and meal tolerance tests; and the hyperglycemic clamp procedure. To provide a meaningful evaluation of BCF, it is necessary to interpret all observations within the context of insulin resistance. Therefore, this review also discusses methods utilized to quantitate insulin-dependent glucose metabolism, such as the IVGTT and the euglycemic-hyperinsulinemic clamp procedures. In addition, an example is presented of a mathematical modeling approach that can use data from BCF measurements to develop a better understanding of BCF behavior and the overall status of glucose tolerance.
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Affiliation(s)
| | | | | | | | - Curtis L Triplitt
- Texas Diabetes Institute, University of Texas Health Science Center-San Antonio, 701 S. Zarzamora, MS 10-5, San Antonio, TX 78207, USA.
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Oliveira JM, Rebuffat SA, Gasa R, Burks DJ, Garcia A, Kalko SG, Zafra D, Guinovart JJ, Gomis R. Tungstate promotes β-cell survival in Irs2-/- mice. Am J Physiol Endocrinol Metab 2014; 306:E36-47. [PMID: 24253047 DOI: 10.1152/ajpendo.00409.2013] [Citation(s) in RCA: 13] [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] [Indexed: 01/09/2023]
Abstract
Pancreatic β-cells play a central role in type 2 diabetes (T2D) development, which is characterized by the progressive decline of the functional β-cell mass that is associated mainly with increased β-cell apoptosis. Thus, understanding how to enhance survival of β-cells is key for the management of T2D. The insulin receptor substrate-2 (IRS-2) protein is pivotal in mediating the insulin/IGF signaling pathway in β-cells. In fact, IRS-2 is critically required for β-cell compensation in conditions of increased insulin demand and for β-cell survival. Tungstate is a powerful antidiabetic agent that has been shown to promote β-cell recovery in toxin-induced diabetic rodent models. In this study, we investigated whether tungstate could prevent the onset of diabetes in a scenario of dysregulated insulin/IGF signaling and massive β-cell death. To this end, we treated mice deficient in IRS2 (Irs2(-/-)), which exhibit severe β-cell loss, with tungstate for 3 wk. Tungstate normalized glucose tolerance in Irs2(-/-) mice in correlation with increased β-cell mass, increased β-cell replication, and a striking threefold reduction in β-cell apoptosis. Islets from treated Irs2(-/-) exhibited increased phosphorylated Erk1/2. Interestingly, tungstate repressed apoptosis-related genes in Irs2(-/-) islets in vitro, and ERK1/2 blockade abolished some of these effects. Gene expression profiling showed evidence of a broad impact of tungstate on cell death pathways in islets from Irs2(-/-) mice, consistent with reduced apoptotic rates. Our results support the finding that β-cell death can be arrested in the absence of IRS2 and that therapies aimed at reversing β-cell mass decline are potential strategies to prevent the progression to T2D.
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Affiliation(s)
- Joana Moitinho Oliveira
- Diabetes and Obesity Research Laboratory, Institut d'Investigations Biomediques August Pi i Sunyer, Barcelona, Spain
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12
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Oishi M, Yamazaki K, Okuguchi F, Sugimoto H, Kanatsuka A, Kashiwagi A. Changes in oral antidiabetic prescriptions and improved glycemic control during the years 2002-2011 in Japan (JDDM32). J Diabetes Investig 2013; 5:581-7. [PMID: 25411627 PMCID: PMC4188117 DOI: 10.1111/jdi.12183] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Revised: 08/27/2013] [Accepted: 10/27/2013] [Indexed: 11/30/2022] Open
Abstract
Aims/Introduction Six kinds of oral antidiabetic drugs (OADs), including the new dipeptidyl peptidase 4 (DPP‐4) inhibitors, are available. The present study aimed to define trends within the prescribing patterns of OADs, as well as changes in glycemic control in Japan over a 10‐year period from 2002 to 2011. Materials and Methods We carried out a cross‐sectional study using data of type 2 diabetes mellitus patients from 24 clinics for 2002, 2005, 2008 and 2011. OAD use was analyzed combined with clinical data. Results Sulfonylureas (SUs) were the most commonly used OAD, but their use for monotherapy markedly decreased over the study period. Biguanides (BGs) were the second most commonly used OAD, and their prescribing rate increased both for mono‐ and combination therapy. DPP‐4 inhibitors (DPP‐4I), released in 2009, were the third most commonly prescribed OAD in 2011 both for mono‐ and combination therapy. Among combination therapies, two OADs were mostly prescribed, but the use of three OADs and four OADs in 2011 was two‐ and 14.8‐fold those in 2002. These trends were accompanied by an improvement in average glycated hemoglobin from 7.5 ± 1.2% in 2002 to 7.1 ± 0.9% in 2011. Conclusions The OAD prescribing trend has moved away from monotherapy with SUs and toward combination therapies to achieve better glycemic control. Increased use of BGs and DPP‐4I was predominant in 2011. These trends were accompanied by an improvement of the glycated hemoglobin level.
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Miyagawa K, Kondo T, Goto R, Matsuyama R, Ono K, Kitano S, Kawasaki S, Igata M, Kawashima J, Matsumura T, Motoshima H, Araki E. Effects of combination therapy with vildagliptin and valsartan in a mouse model of type 2 diabetes. Cardiovasc Diabetol 2013; 12:160. [PMID: 24188631 PMCID: PMC4176757 DOI: 10.1186/1475-2840-12-160] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Accepted: 10/20/2013] [Indexed: 01/13/2023] Open
Abstract
Background Dipeptidyl peptidase-4 (DPP-4) inhibitors modulate incretin hormones and exert anti-diabetic effects in type 2 diabetes mellitus. Treatment with angiotensin II type 1 receptor blockers (ARB) is a proven successful intervention for hypertension with type 2 diabetes. The present study investigated the combined effects of the DPP-4 inhibitor vildagliptin and the ARB valsartan in a mouse model of type 2 diabetes. Methods C57BL/6 J mice fed with high-fat diet (HFD) or db/db mice were treated with placebo, phloridzin (PHZ), vildagliptin alone (ViL), valsartan alone (VaL) or ViL with VaL (ViLVaL) for 8 weeks. Results Glucose metabolism was improved in response to PHZ, ViL and ViLVaL in both HFD and db/db mice. Upon glucose challenge, ViLVaL showed the greatest suppression of blood glucose excursions, with increased insulin secretion, in db/db mice. ViLVaL treatment also showed an improvement of insulin sensitivity in db/db mice. Serum inflammatory cytokines were significantly decreased, and adiponectin was highest, in the ViLVaL group. ViLVaL improved insulin signaling and attenuated stress signaling in liver with amelioration of hepatic steatosis due to activated fatty acid oxidation in db/db mice. Furthermore, immunohistochemical analysis of the pancreas revealed that the combination treatment resulted in an increased expression of insulin and PDX-1, and increased insulin content. Conclusions The combination therapy of ViL and VaL improves both pancreatic beta-cell function and insulin sensitivity, with a reduction of the inflammatory and cell stress milieu in mouse models of T2DM. Our results suggest that this combination therapy exerts additive or even synergistic benefits to treat T2DM.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - Eiichi Araki
- Department of Metabolic Medicine, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Chuo Ward, Kumamoto 860-8556, Japan.
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14
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The effects of dipeptidyl-peptidase-IV inhibitor, vildagliptin, on the exocrine pancreas in spontaneously diabetic Goto-Kakizaki rats. Pancreas 2013; 42:786-94. [PMID: 23774700 DOI: 10.1097/mpa.0b013e318287c9b5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
OBJECTIVES The risk of adverse effects of dipeptidyl peptidase-4 inhibitors on the exocrine pancreas, particularly the high risk of pancreatitis, is controversial. In this study, we examined the exocrine pancreatic function and structure in spontaneously diabetic Goto-Kakizaki (GK) rats treated with a dipeptidyl peptidase-4 inhibitor. METHODS Male GK rats and normal Wistar rats 4 weeks of age were treated with vildagliptin (VG; 30 mg/kg/d) for 18 weeks. Subsequently, exocrine pancreatic pathology and function in treated animals were compared to those in untreated animals. RESULTS In GK rats, VG treatment suppressed elevated serum concentrations of amylase and lipase, reduced lymphocytic infiltration around ducts, around vessels, and in acinar areas, and reduced the frequency of apoptotic acinar cells and ductule formation (both of which occurred more frequently in GK rats than Wistar rats). However, VG treatment had no effect on the proliferation rate of pancreatic duct glandular cells (which was low in GK rats) and of cells in the main ducts, peripheral ducts, and acini (which was similar in all groups). CONCLUSIONS Perturbations of exocrine pancreatic function and structure in GK rats are ameliorated by long-term VG treatment.
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Pan C, Wang X. Profile of vildagliptin in type 2 diabetes: efficacy, safety, and patient acceptability. Ther Clin Risk Manag 2013; 9:247-57. [PMID: 23818788 PMCID: PMC3694507 DOI: 10.2147/tcrm.s30071] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Indexed: 12/26/2022] Open
Abstract
Vildagliptin is a selective and potent dipeptidyl peptidase-4 inhibitor that improves glycemic
control by inhibiting the degradation of both endogenous glucagon-like peptide-1 and
glucose-dependent insulinotropic peptide. This article is a comprehensive review of the safety and
efficacy of vildagliptin in patients with type 2 diabetes. Clinical evidence has proven that it
effectively decreases hemoglobin A1c with a low risk of hypoglycemia and is weight
neutral. The addition of vildagliptin to metformin improves glucose control and significantly
reduces gastrointestinal adverse events, particularly in patients inadequately controlled with
metformin monotherapy. Its long-term advantages include preservation of β-cell function,
reduction in total cholesterol, decrease in fasting lipolysis in adipose tissue, and triglyceride
storage in non-fat tissues. Vildagliptin is well tolerated with a low incidence of AEs, and it does
not increase the risk of cardiovascular/cerebrovascular (CCV) events. It can be taken before or
after meals, and has little drug interaction, thus it will be well accepted.
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Affiliation(s)
- Cy Pan
- Chinese PLA General Hospital, Beijing, People's Republic of China
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Pipatpiboon N, Pintana H, Pratchayasakul W, Chattipakorn N, Chattipakorn SC. DPP4-inhibitor improves neuronal insulin receptor function, brain mitochondrial function and cognitive function in rats with insulin resistance induced by high-fat diet consumption. Eur J Neurosci 2012; 37:839-49. [DOI: 10.1111/ejn.12088] [Citation(s) in RCA: 126] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Accepted: 11/09/2012] [Indexed: 01/02/2023]
Affiliation(s)
- Noppamas Pipatpiboon
- Neurophysiology Unit; Faculty of Medicine; Cardiac Electrophysiology Research and Training Center, Chiang Mai University; Chiang Mai; 50200; Thailand
| | - Hiranya Pintana
- Neurophysiology Unit; Faculty of Medicine; Cardiac Electrophysiology Research and Training Center, Chiang Mai University; Chiang Mai; 50200; Thailand
| | - Wasana Pratchayasakul
- Neurophysiology Unit; Faculty of Medicine; Cardiac Electrophysiology Research and Training Center, Chiang Mai University; Chiang Mai; 50200; Thailand
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