linagliptin and Non-alcoholic-Fatty-Liver-Disease

We validated the effect of linagliptin, an oral dipeptidyl peptidase-4 inhibitor, on nonalcoholic fatty liver disease (NAFLD) in patients with type 2 diabetes mellitus (T2DM). A total of 50 patients with NAFLD and T2DM treated with metformin were randomized (1:1) to metformin plus add-on linagliptin (linagliptin group) or to an increased dose of metformin (metformin group) for 52 weeks. The primary endpoint was change in hepatic steatosis from baseline to week 52 as quantified by unenhanced computed tomography imaging. Secondary endpoints included changes in the levels of anthropometric, biochemical and adipokinetic markers. The linagliptin group showed no statistically significant reduction in hepatic steatosis as compared to the metformin group (P = 0.97), although changes in hepatic steatosis were significantly correlated with decreased liver enzymes in both groups. Body weight was significantly reduced in the metformin group but not in the linagliptin group (P = 0.002). Serum leptin levels were significantly increased in the linagliptin group compared to the metformin group (P = 0.003), and were correlated with the changes body weight in whole samples. Adverse events were not different between the two groups (P = 0.78). Add-on linagliptin demonstrated a safe profile but was not superior to increased metformin in reducing hepatic steatosis.

Topics: Blood Glucose; Diabetes Mellitus, Type 2; Double-Blind Method; Drug Therapy, Combination; Glycated Hemoglobin; Humans; Hypoglycemic Agents; Linagliptin; Metformin; Non-alcoholic Fatty Liver Disease; Purines; Quinazolines; Treatment Outcome

To investigate the effects of linagliptin treatment on hepatic energy metabolism and ER stress in high-fat-fed C57BL/6 mice.. Forty male C57BL/6 mice, three months of age, received a control diet (C, 10% of lipids as energy, n = 20) or high-fat diet (HF, 50% of lipids as energy, n = 20) for 10 weeks. The groups were randomly subdivided into four groups to receive linagliptin, for five weeks, at a dose of 30 mg/kg/day added to the diets: C, C-L, HF, and HF-L groups.. The HF group showed higher body mass, total and hepatic cholesterol levels and total and hepatic triacylglycerol levels than the C group, all of which were significantly diminished by linagliptin in the HF-L group. The HF group had higher hepatic steatosis than the C group, whereas linagliptin markedly reduced the hepatic steatosis (less 52%, P < 0.001). The expression of Sirt1 and Pgc1a was more significant in the HF-L group than in the HF group. Linagliptin also elicited enhanced GLP-1 concentrations and a reduction in the expression of the lipogenic genes Fas and Srebp1c. Besides, HF-L showed a reduction in the genes related to endoplasmic reticulum stress Chop, Atf4, and Gadd45 coupled with reduced apoptotic nuclei immunostaining.. Linagliptin caused a marked reduction in hepatic steatosis as a secondary effect of its glucose-lowering property. NAFLD countering involved reduced lipogenesis, increased beta-oxidation, and relief in endoplasmic reticulum stress, leading to reduced apoptosis and better preservation of the hepatic structure. Therefore, linagliptin may be used, preferably in diabetic patients, to avoid the progression of hepatic steatosis.

Topics: Animals; Apoptosis; Biomarkers; Blood Glucose; Body Weight; Carbohydrate Metabolism; Diet, High-Fat; Eating; Endoplasmic Reticulum Stress; Fasting; Feeding Behavior; Glucagon-Like Peptide 1; Insulin; Insulin Resistance; Linagliptin; Lipid Droplets; Lipids; Lipogenesis; Liver; Male; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease; Oxidation-Reduction; Perilipin-2; Vascular Endothelial Growth Factor A

Abnormal hepatic insulin signaling is a cause or consequence of hepatic steatosis. DPP-4 inhibitors might be protective against fatty liver. We previously reported that the systemic inhibition of insulin receptor (IR) and IGF-1 receptor (IGF1R) by the administration of OSI-906 (linsitinib), a dual IR/IGF1R inhibitor, induced glucose intolerance, hepatic steatosis, and lipoatrophy in mice. In the present study, we investigated the effects of a DPP-4 inhibitor, linagliptin, on hepatic steatosis in OSI-906-treated mice. Unlike high-fat diet-induced hepatic steatosis, OSI-906-induced hepatic steatosis is not characterized by elevations in inflammatory responses or oxidative stress levels. Linagliptin improved OSI-906-induced hepatic steatosis via an insulin-signaling-independent pathway, without altering glucose levels, free fatty acid levels, gluconeogenic gene expressions in the liver, or visceral fat atrophy. Hepatic quantitative proteomic and phosphoproteomic analyses revealed that perilipin-2 (PLIN2), major urinary protein 20 (MUP20), cytochrome P450 2b10 (CYP2B10), and nicotinamide N-methyltransferase (NNMT) are possibly involved in the process of the amelioration of hepatic steatosis by linagliptin. Thus, linagliptin improved hepatic steatosis induced by IR and IGF1R inhibition via a previously unknown mechanism that did not involve gluconeogenesis, lipogenesis, or inflammation, suggesting the non-canonical actions of DPP-4 inhibitors in the treatment of hepatic steatosis under insulin-resistant conditions.

Topics: Animals; Aryl Hydrocarbon Hydroxylases; Blood Glucose; Cytochrome P450 Family 2; Gene Expression Regulation; Hepatocytes; Imidazoles; Insulin; Intercellular Signaling Peptides and Proteins; Linagliptin; Male; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease; Perilipin-2; Pyrazines; Receptor, IGF Type 1; Receptor, Insulin; Steroid Hydroxylases; Triglycerides

Non-alcoholic steatohepatitis (NASH) is characterized by the presence of hepatic steatosis, oxidative stress, inflammation, and hepatocyte injury with or without fibrosis. In this study, we explored the effect of APD668, a GPR119 agonist alone or in combination with linagliptin, a DPPIV inhibitor, on the progression of steatohepatitis in a murine model of NASH with diabetes. A novel NASH model with diabetes was generated by administration of streptozotocin injection to neonatal C57BL/6 mice (2-3 days old) combined with a high-fat diet feeding from the age of 4 weeks. The plasma biochemical parameters, oxidative stress, inflammation and histopathological changes were assessed. APD668 alone showed reduction in plasma glucose (- 39%, P < 0.05) and triglyceride level (- 26%) whereas a combined treatment of APD668 with linagliptin resulted in a more pronounced reduction in plasma glucose (- 52%, P < 0.001) and triglyceride (- 50%, P < 0.05) in NASH mice. In addition, co-administration of APD668 with linagliptin demonstrated a significant decrease in hepatic triglyceride, NAS score, hepatic TBARS and hepatic TNF-α in NASH mice with diabetes. These findings suggest that GPR119 receptor agonists in combination with DPPIV inhibitors may represent a promising therapeutic strategy for the treatment of NASH.

Topics: Animals; Diabetes Mellitus, Experimental; Diet, High-Fat; Dipeptidyl-Peptidase IV Inhibitors; Disease Progression; Fibrosis; Inflammation; Linagliptin; Liver; Male; Mice; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease; Oxidative Stress; Pyrazoles; Pyrimidines; Receptors, G-Protein-Coupled

We studied the effects of dipeptidyl peptidase 4 (DPP4) inhibitor linagliptin on the expression of apoptosis regulator proteins Bcl-2 and Bad in the liver of db/db mice with genetically determined obesity and type 2 diabetes mellitus. The mice received daily linagliptin or saline (placebo) by gavage from week 10 to week 18 of life. In the liver of non-treated mice, the area positively stained for Bad was greater than the area of Bcl-2 expression, which created the conditions for apoptosis activation in liver at this age. Administration of linagliptin decreased Bad stained area and increased Bcl-2 stained area in the liver cells. At the same time, Bad stained area remained larger in treated mice than the area of Bcl-2 expression area, which attested to partial normalization of pro- and antiapoptotic protein balance.

Topics: Animals; Apoptosis; bcl-Associated Death Protein; Diabetes Mellitus, Type 2; Dipeptidyl-Peptidase IV Inhibitors; Linagliptin; Liver; Male; Mice; Non-alcoholic Fatty Liver Disease; Obesity; Proto-Oncogene Proteins c-bcl-2

Non-Alcoholic SteatoHepatitis (NASH) is the more severe form of Non-Alcoholic Fatty Liver Disease (NAFLD) and is characterized by the presence of hepatic steatosis, oxidative stress, inflammation, hepatocyte injury with or without fibrosis. Recently, GPR119 receptor has emerged as a novel therapeutic target for the treatment of dyslipidemia and non-alcoholic steatohepatitis. In the present study, we investigated the effect of APD668, a GPR119 agonist alone or in combination with linagliptin, a DPPIV inhibitor on the progression of steatohepatitis in mice fed on a high trans-fat diet. In this study, monotherapy with either APD668 or linagliptin caused a reduction in the levels of ALT, AST, glucose, cholesterol and epididymal fat mass but the effect was more pronounced upon treatment with combination of both drugs. On the other hand, combined treatment of APD668 with linagliptin demonstrated a non-significant additive effect in reduction of hepatic triglyceride (-78%) and cholesterol (-56%) compared to monotherapy groups. Moreover, co-administration of APD668 and linagliptin resulted in enhanced levels of active GLP-1 with additional benefit of significant synergistic decrease in body weight gain (-19%) in mice. We speculated that the enhanced effect observed with the combination treatment could be due to either 1) direct activation of GPR119 receptors present in liver and intestine or 2) enhanced active GLP-1 levels or 3) decreased degradation of GLP-1 in-vivo through DPPIV inhibition. Therefore, these findings clearly suggest that GPR119 receptor agonists in combination with DPPIV inhibitors may represent a promising therapeutic strategy for the treatment of non-alcoholic steatohepatitis.

Topics: Animals; Diet, High-Fat; Dipeptidyl-Peptidase IV Inhibitors; Disease Models, Animal; Disease Progression; Drug Synergism; Drug Therapy, Combination; Linagliptin; Liver; Male; Mice; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease; Pyrazoles; Pyrimidines; Receptors, G-Protein-Coupled; Weight Gain

G-protein coupled receptor 119 (GPR119) receptor is a rhodopsin-like, class A Gαs-coupled receptor, predominantly expressed in pancreatic islet cells and intestinal entero-endocrine cells. GPR119 has been emerged as a novel therapeutic target for the treatment of dyslipidemia in type 2 diabetes. In this study, we investigated the effect of APD668, a GPR119 agonist alone and in combination with linagliptin, a DPPIV inhibitor on oral fat tolerance test. Our findings demonstrate that APD668, a GPR119 agonist inhibits the intestinal triglyceride absorption after acute fat load in mice. Single dose administration of APD668 increases incretin secretion and enhances total PYY levels in presence of fat load in mice. We found that, the anti-dyslipidemic action of APD668 was reversed in presence of exendin-3 in oral fat tolerance test. In addition, our results showed that exendin-3 (9-39) failed to block the effect of APD668 on gastric emptying indicating that gastric emptying effects of APD668 are indeed mediated through GPR119 receptor dependent mechanism. Combined administration of APD668 and linagliptin significantly increased plasma active GLP-1 levels in-vivo and showed improvement in fat tolerance. However, APD668 failed to show anti-dyslipidemic activity in tyloxapol-induced hyperlipidemia in mice. Furthermore, we investigated the chronic effects of APD668 on hepatic steatosis in high trans-fat diet fed steatohepatitis model in mice. Oral administration of APD668 in HTF diet fed mice ameliorated hepatic endpoints such as plasma ALT, AST, liver weight and steatosis. These findings suggest that GPR119 agonists may represent a promising therapeutic strategy for the treatment of dyslipidemia and non-alcoholic steatohepatitis.

Topics: Animals; Diet, High-Fat; Drug Interactions; Gastric Emptying; Glucagon-Like Peptide 1; Glucagon-Like Peptide-1 Receptor; Linagliptin; Male; Mesylates; Mice; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease; Oxadiazoles; Polyethylene Glycols; Pyrazoles; Pyrimidines; Receptors, G-Protein-Coupled; Tetrazoles; Thiazoles; Triglycerides

Non-alcoholic steatohepatitis (NASH) is a primary cause of cirrhosis and hepatocellular carcinoma. Dipeptidyl peptidase (DPP)-4 inhibitors are established therapies for type 2 diabetes and although DPP-4 inhibitors can reduce hepatic steatosis, their impact on local inflammation and fibrosis in NASH remains unknown. Using two different experimental treatment regimens (4- and 2-week treatments) in streptozotocin-treated neonatal mice on a high-fat diet, we show that the DPP-4 inhibitor linagliptin (10 and 30 mg/kg) significantly attenuated the NAS score from 4.9 ± 0.6 to 3.7 ± 0.4 and 3.6 ± 0.3, respectively, in the 4-week study. In the 2-week study, linagliptin 10 mg/kg significantly reduced NAS score from 4.1 ± 0.4 to 2.4 ± 0.4. Telmisartan was used as a positive control in both studies and lowered NAS score to 1.9 ± 0.7 and 1.4 ± 0.3, respectively. Due to streptozotocin treatment, elevated glucose levels were unchanged by either drug treatment. Further, linagliptin 10 mg/kg significantly reduced mRNA levels of SOCS-3 (from 1.68 ± 0.2 to 0.83 ± 0.08), IFN-γ (from 4.0 ± 0.5 to 2.3 ± 0.3), and TNF-α (from 5.7 ± 0.5 to 2.13 ± 0.3). The latter observation was confirmed by immunohistochemistry of TNF-α in liver specimens. In addition, using microautoradiography, we showed that the distribution of radiolabeled linagliptin was heterogeneous with the highest density associated with interlobular bile ducts and portal tracts (acini). In conclusion, these studies confirm that linagliptin has high exposure in hepatic tissue and has both anti-inflammatory and anti-steatotic activity in NASH.

Topics: Animals; Animals, Newborn; Autoradiography; Diet, High-Fat; Dipeptidyl Peptidase 4; Dipeptidyl-Peptidase IV Inhibitors; DNA Primers; Immunohistochemistry; Interferon-gamma; Linagliptin; Mice; Non-alcoholic Fatty Liver Disease; Purines; Quinazolines; Real-Time Polymerase Chain Reaction; RNA, Messenger; Streptozocin; Suppressor of Cytokine Signaling 3 Protein; Suppressor of Cytokine Signaling Proteins; Time Factors; Tumor Necrosis Factor-alpha