Metabolic and Anti-inflammatory Response to Melatonin Administration in Patients with Diabetic Nephropathy.

INTRODUCTION: Data on the effects of melatonin administration on metabolic parameters in patients with diabetic nephropathy (DN) is limited and controversial. This study was performed to analyze the effects of melatonin administration on metabolic status in patients with DN. METHODS: This randomized, double blind, placebo-controlled clinical trial was performed on 60 patients with DN. Patients were randomly assigned into two groups to take either 10 mg/d of melatonin (n = 30) or placebo (n = 30) for 12 weeks. Fasting blood samples were taken at baseline and 12 weeks after intervention to quantify metabolic parameters. RESULTS: Melatonin administration significantly reduced plasma fasting glucose (ß = -10.64 mg/dL; 95% CI: -20.37 to -0.90; P < .05), insulin (ß = -2.37 µIU/mL, 95% CI: -3.33 to -1.41; P < .001), insulin resistance (ß = -0.67, 95% CI: -0.98 to -0.35; P < .001), significantly increased insulin sensitivity (ß = 0.01, 95% CI: 0.006 to 0.01; P < .05), and plasma HDL-cholesterol levels (ß = 2.75 mg/dL, 95% CI: 0.75 to 4.75; P < .05) when compared with the placebo. Melatonin also caused a significant increase in total antioxidant capacity (TAC) (ß = 140.45 mmol/L; 95% CI: 80.48 to 200.41; P < .001), and glutathione (GSH) levels (ß = 50.36 µmol/L, 95% CI: 94.08 to 0.02; P < .05) when compared with placebo. Ultimately, melatonin could upregulate gene expression of peroxisome proliferator-activated receptor gamma (PPAR-γ) (P < .05) in comparison with placebo. CONCLUSION: Results of this study indicated that melatonin administration for 12 weeks in DN patients had beneficial effects on glycemic control, HDL-cholesterol, TAC and GSH levels, and gene expression of PPAR-γ, but did not affect other metabolic parameters.

The effects of n-3 fatty acids from flaxseed oil on genetic and metabolic profiles in patients with gestational diabetes mellitus: a randomised, double-blind, placebo-controlled trial.

The present study was performed to evaluate the effects of n-3 fatty acids from flaxseed oil on genetic and metabolic profiles in patients with gestational diabetes mellitus (GDM). This randomised, double-blind, placebo-controlled clinical trial was performed in sixty women with GDM. Participants were randomly divided into two groups to intake either 2 × 1000 mg/d n-3 fatty acids from flaxseed oil containing 400 mg α-linolenic acid in each capsule (n 30) or placebo (n 30) for 6 weeks. n-3 Fatty acid intake up-regulated PPAR-γ (P < 0·001) and LDL receptor (P = 0·004) and down-regulated gene expression of IL-1 (P = 0·002) and TNF-α (P = 0·001) in peripheral blood mononuclear cells of subjects with GDM. In addition, n-3 fatty acid supplementation reduced fasting plasma glucose (P = 0·001), insulin levels (P = 0·001) and insulin resistance (P < 0·001) and increased insulin sensitivity (P = 0·005) when compared with the placebo. Additionally, n-3 fatty acid supplementation was associated with a decrease in TAG (P < 0·001), VLDL-cholesterol (P < 0·001), total cholesterol (P = 0·01) and total cholesterol:HDL-cholesterol ratio (P = 0·01) when compared with placebo. n-3 Fatty acid administration was also associated with a significant reduction in high-sensitivity C-reactive protein (P = 0·006) and malondialdehyde (P < 0·001), and an increase in total nitrite (P < 0·001) and total glutathione levels (P = 0·006) when compared with the placebo. n-3 Fatty acid supplementation for 6 weeks to women with GDM had beneficial effects on gene expression related to insulin, lipid and inflammation, glycaemic control, lipids, inflammatory markers and oxidative stress.

Association between miRNAs expression and signaling pathways of oxidative stress in diabetic retinopathy.

Diabetic retinopathy (DR) is a major cause of vision reduction in diabetic patients. Hyperglycemia is a known instigator for the development of DR, even though the role of oxidative stress pathways in the pathogenesis of DR is established. The studies indicate that microRNAs (miRNAs) are significant to the etiology of DR; changes in miRNAs expression levels may be associated with onset and progression of DR. In addition, miRNAs have emerged as a useful disease marker due to their availability and stability in detecting the severity of DR. The relationship between miRNAs expression levels and oxidative stress pathways has been investigated in several studies. The aim of this study is the examination of function and expression levels of target miRNAs in oxidative stress pathway and pathogenesis of diabetic retinopathy.

The Effects of Probiotic Supplementation on Genetic and Metabolic Profiles in Patients with Gestational Diabetes Mellitus: a Randomized, Double-Blind, Placebo-Controlled Trial.

This study was carried out to evaluate the effects of probiotic supplementation on genetic and metabolic profiles in patients with gestational diabetes mellitus (GDM) who were not on oral hypoglycemic agents. This randomized, double-blind, placebo-controlled clinical trial was conducted in 48 patients with GDM. Participants were randomly divided into two groups to intake either probiotic capsule containing Lactobacillus acidophilus, Lactobacillus casei, Bifidobacterium bifidum, Lactobacillus fermentum (2 × 109 CFU/g each) (n = 24) or placebo (n = 24) for 6 weeks. Probiotic intake upregulated peroxisome proliferator-activated receptor gamma (P = 0.01), transforming growth factor beta (P = 0.002) and vascular endothelial growth factor (P = 0.006), and downregulated gene expression of tumor necrosis factor alpha (P = 0.03) in peripheral blood mononuclear cells of subjects with GDM. In addition, probiotic supplementation significantly decreased fasting plasma glucose (ß, - 3.43 mg/dL; 95% CI, - 6.48, - 0.38; P = 0.02), serum insulin levels (ß, - 2.29 µIU/mL; 95% CI, - 3.60, - 0.99; P = 0.001), and insulin resistance (ß, - 0.67; 95% CI, - 1.05, - 0.29; P = 0.001) and significantly increased insulin sensitivity (ß, 0.009; 95% CI, 0.004, 0.01; P = 0.001) compared with the placebo. Additionally, consuming probiotic significantly decreased triglycerides (P = 0.02), VLDL-cholesterol (P = 0.02), and total-/HDL-cholesterol ratio (P = 0.006) and significantly increased HDL-cholesterol levels (P = 0.03) compared with the placebo. Finally, probiotic administration led to a significant reduction in plasma malondialdehyde (P < 0.001), and a significant elevation in plasma nitric oxide (P = 0.01) and total antioxidant capacity (P = 0.01) was observed compared with the placebo. Overall, probiotic supplementation for 6 weeks to patients with GDM had beneficial effects on gene expression related to insulin and inflammation, glycemic control, few lipid profiles, inflammatory markers, and oxidative stress.

The effects of microRNAs in activating neovascularization pathways in diabetic retinopathy.

Diabetic retinopathy (DR) is one of the major complications of diabetes mellitus that causes diabetic macular edema and visual loss. DR is categorized, based on the presence of vascular lesions and neovascularization, into non-proliferative and proliferative DR. Vascular changes in DR correlate with the cellular damage and pathological changes in the capillaries of blood-retinal barrier. Several cytokines have been involved in inducing neovascularization. These cytokines activate different signaling pathways which are mainly responsible for the complications of DR. Recently; microRNAs (miRNAs) have been introduced as the key factors in the regulation of the cytokine expression which plays a critical role in neovascularization of retinal cells. Some studies have demonstrated that changing levels of miRNAs have essential role in the pathophysiology of vascular changes in patients with DR. The aim of this study is to identify the effects of miRNAs in the pathogenesis of DR via activating neovascularization pathways.