SH3YL1 protein as a novel biomarker for diabetic nephropathy in type 2 diabetes mellitus.

BACKGROUND AND AIMS: Oxidative stress contributes to development of diabetic nephropathy. We implicated SH3YL1 in oxidative stress-induced inflammation and examined whether SH3YL1 could be used as a new biomarker of diabetic nephropathy. METHODS AND RESULTS: In this study, we investigated the relationship between plasma level of SH3YL1 and diabetic nephropathy in patients with type 2 diabetes. In addition, we examined the physiological role of SH3YL1 in db/db mice and cultured podocytes. Plasma SH3YL1 concentration was significantly higher in patients with diabetes than in controls, even in normoalbuminuric patients, and was markedly increased in the macroalbuminuria group. Plasma SH3YL1 level was positively correlated with systolic blood pressure, HOMA-IR, postprandial blood glucose, plasma level of retinol binding protein 4 (RBP 4), and urinary albumin excretion (UAE) and was inversely correlated with BMI. Regression analysis showed that plasma level of RBP 4, UAE, and BMI were the only independent determinants of plasma SH3YL1 concentration. In db/db mice, plasma and renal SH3YL1 levels were significantly increased in mice with diabetes compared with control mice. In cultured podocytes, high glucose and angiotensin II stimuli markedly increased SH3YL1 synthesis. CONCLUSION: These findings suggest that plasma level of SH3YL1 offers a promising new biomarker for diabetic nephropathy.

Efficacy, safety and albuminuria-reducing effect of gemigliptin in Korean type 2 diabetes patients with moderate to severe renal impairment: A 12-week, double-blind randomized study (the GUARD Study).

AIMS: This multicentre, randomized, double-blind study investigated the efficacy and safety of gemigliptin in Korean type 2 diabetes mellitus (T2DM) patients with moderate to severe renal impairment (RI). METHODS: The study comprised a 12-week main part and a 40-week extension. We report here the results from the main part. In total, 132 patients were randomized to receive gemigliptin (n = 66) or placebo (n = 66). Changes in glycated haemoglobin (HbA1c; primary endpoint), other glycaemic control parameters (fasting plasma glucose, glycated albumin and fructosamine), lipid profiles, renal function parameters and safety profiles were evaluated. RESULTS: Baseline characteristics were comparable between the groups (mean HbA1c, 8.4% [68 mmol/mol]; age, 62.0 years; duration of type 2 diabetes, 16.3 years; estimated glomerular filtration rate, 33.3 mL/min/1.73 m2 ). At Week 12, the adjusted mean change ± standard error in HbA1c with gemigliptin was -0.82% ± 0.14% (-8.9 ± 1.5 mmol/mol), whereas it was 0.38% ± 0.14% (4.2 ± 1.5 mmol/mol) with placebo (significant between-group difference, P < .001). Other glycaemic control parameters showed beneficial changes as well. Body weight change (gemigliptin, -0.3 kg; placebo, -0.2 kg) was not significant. In the gemigliptin group, the mean decrease in urinary albumin creatinine ratio (UACR) was significant, both in patients with microalbuminuria (-41.9 mg/g creatinine, P = .03) and macroalbuminuria (-528.9 mg/g creatinine, P < .001). Drug-related adverse events were similar with gemigliptin and placebo (15% and 12%, respectively). CONCLUSIONS: A 12-week treatment with gemigliptin improved glycaemic control and provided UACR reduction in T2DM patients with moderate to severe RI. Gemigliptin was well tolerated, with no additional risk of hypoglycaemia and change in body weight.

Angiotensin receptor blockers improve insulin resistance in type 2 diabetic rats by modulating adipose tissue.

Adipose tissue is recognized as a pivotal organ in the development of insulin resistance. This study seeks to determine the effect of angiotensin receptor blockade (ARB) on insulin resistance of adipocytes in culture and in a rat model of type 2 diabetes. Treatment of Otsuka Long-Evans Tokushima Fatty rats with the ARB L158809 for six months significantly lowered fasting plasma glucose, cholesterol and triglyceride levels but led to higher plasma adiponectin levels. Insulin resistance, measured by an intraperitoneal glucose tolerance test, of the treated rats was significantly improved along with an increase in the number of small differentiated adipocytes; however, epididymal fat mass decreased. Treatment significantly lowered lipid peroxidation and MCP-1 expression while increasing adiponectin production by the adipose tissue. ARB treatment significantly improved insulin sensitivity and markedly suppressed AT2-induced oxidative stress, PAI-1 and MCP-1 levels and NF-kappaB activation of adipocytes in culture. Treatment increased adiponectin and PPARgamma expression along with intracellular triglyceride levels reflecting differentiation of the cultured adipocytes. Our study suggests that ARB treatment improves insulin resistance by modification of adipose tissue thereby blunting the development of diabetes.