Background: Astaxanthin suppressed obesity in rats fed with high-fat diet (HFD) via the restriction of adipose tissue build-out, therefore, improving insulin sensitivity and inflammation. Metformin reduces insulin resistance and may reduce weight.
Aim: Investigation of the effects of astaxanthin and metformin in obesity prompted by a high-fat diet.
Objective: The present article investigates the effects of astaxanthin and metformin in obesity prompted by a high-fat diet in rats through measuring miRNA222 and 378.
Materials: The rats were classified into four classes containing ten albino rats each: Group I (Normal group): nourished with ordinary diet for 8weeks. Group II (Control positive): nourished with a high-fat diet for 8 weeks. Group III: nourished with astaxanthin (50mg/kg)(1/40 LD50) orally plus a high-fat diet for 8weeks. Group IV: nourished with metformin (500mg/kg) orally plus a high-fat diet for 8 weeks.
Methods: Leptin, adiponectin, calprotectin and interleukin 6 (IL-6) were assessed by rat-specific ELISA kits. Tumor necrosis factor-alpha (TNF-α), miRNA222 and miRNA378 expressions were quantified by quantitative real-time PCR.
Results: Astaxanthin and metformin have anti-obesity and antioxidant actions and significantly decreased the weight of the body, glucose, insulin, triglycerides, total cholesterol, triglycerides and leptin, as well as plasma calprotectin & IL-6 and increased HDL-C and adiponectin. The liver TNF-α gene expression, adipose tissue miRNA222 and miRNA378 expression were decreased compared to HFD control rats.
Discussion and conclusion: Astaxanthin has regulated the aberrant expression of miRNA222 and 378 that may be related to hyperlipidemia and insulin resistance. Accordingly, astaxanthin deserves a clinical trial in the future due to its effects on miRNAs involved in obesity.
Keywords: Adiponectin, astaxanthin, calprotectin, miRNA222, miRNA378, obesity.