Serum Testosterone Levels of Aging SD Male Rats and Effects of Marine Collagen Peptides

Objective To investigate the serum testosterone level of aging SD male rats and the effect of marine collagen peptides(MCPs) on them.Method 48 SD male rats were randomly divided into 4 groups according to their different doses of MCPs (0 control, 2.25%, 4.50% and 9.00%) with 12 rats in each. Serum testosterone was measured at the ages of 12, 18 and 24-month. MDA contents and SOD, GSH-Px activities in blood serum were measured at the ages of 12,18 and 24-month.Results Serum testosterone levels of 12, 18 and 24-month-old rats in control group were 0.89±0.16, 0.58±0.23, 0.30± 0.11 ng/ml . Serum testosterone level of 4.50% dose group was significantly higher than those of control group and serum testosterone level of 9.00% dose group was significantly lower at the ages of 12-month. Compared with the 12-month-old rats, serum testosterone levels of all groups in 18-month-old rats were significantly lower. Compared with control group, MDA levels of serum were significantly lower and the activities of serum SOD and GSH-Px were obviously higher in three dose groups at 12-month-old. At 18-month-old, serum MDA levels of 4.50% and 9.00% dose group were lower than control group and the activities of serum SOD in three dose groups were still higher. The serum MDA levels of all the groups increased, and the activities of serum SOD and GSH-Px decreased as the rats got older.Conclusion Serum testosterone level of aging SD male rats decreased, and MCPs could affect them as the antioxidants if the rats were treated at an early age.