[Effects of marine collagen peptides on blood glucose and lipid metabolism in hyperinsulinemic rats]

Abstract

Objective: To observe the effects of marine collagen peptides (MCPs) on blood glucose and lipid metabolism in hyperinsulinemic rats.

Methods: Male SD rats fed with high fat diet for 4 months were used to establish a hyperinsulinemic model. Thirty two hyperinsulinemic rats were divided into four groups according to body weight and serum insulin level, namely hyperinsulinemic control (HIC) group and 3 Marine Collagen Peptides treated groups with 8 rats in each group. Another 8 healthy male SD rats fed with basic diet were used as negative control (NC). Rats in MCPs groups were treated by intragastric way with MCPs at the dose of 0.225 g/kg bw, 0.45 g/kg bw and 1.35 g/kg bw respectively for 8 weeks, while rats in HIC and NC groups were treated with tap water in the same manner. During the test period, rats in HIC and MCPs groups were fed with high fat diet sequentially, while rats in NC group were fed with basic diet. Fasting serum glucose (GLU), insulin (INS) and lipids were assayed respectively before and after MCPs treatment. Oral glucose tolerance test, antioxidase activity, serum malondialdehyde (MDA) levels and the ultrastructure of islet beta cell were carried out at the end of the experiment.

Results: After 8 weeks of treatment, compared with HIC group, fasting INS, TC and TG of all three MCPs-treated groups decreased obviously, while fasting GLU level lowered significantly in 0.225 g/kg bw and 1.35 g/kg bw MCPs groups. Moreover, GLU level at 0.5 h, 2 h and the area under blood sugar curve in OGTT were evidently lower in 0.45 g/kg bw and 1.35 g/kg bw MCPs groups. Besides, serum SOD activity increased in all MCPs groups, and serum GSH-Px activity elevated obviously in 1.35 g/kg bw MCPs group, while serum MDA reduced. Finally, the ultrastructural impairment of islet resulted from high fat diet was improved evidently by 1.35 g/kg bw MCPs.

Conclusion: MCPs was effective in improving glucose and lipid metabolism in hyperinsulinemic rats induced by high fat diet.