Abstract:

Objective: To determine natural lycopene accumulation in the serum and liver of male and female rats and analyze the difference in lycopene accumulation between male and female rats. Methods: One hundred and thirty-six male and 408 female SD rats with body weight of (250 ± 5) g were randomly divided 17 and 51 groups of 8 rats each, respectively. As for female rats, 17 groups were subjected to ovariectomization surgery, 17 other groups were subjected to pseudo-surgery and the rest were used as the controls. The gastric administration solution was prepared from natural lycopene extract and salad oil with a final lycopene concentration of 0.625 mg/mL. Each of the rats was fed natural lycopene at a dose of 1 mL of solution by single gastric administration. Eight milliliters of blood of each rat from male and female controls, surgery and pseudo-surgery groups was collected and 4 g of liver tissue of those rats was harvested at fixed time points. Total carotenoids were extracted from harvested sera and liver samples, and lycopene content was determined by C18-HPLC external standard method. Results: Compared with female rats, the maximum accumulation of lycopene in serum and liver tissues of male rats exhibited a faster rate and higher level. In addition, the maximum accumulation of lycopene exhibited a significant increase in serum of female rats and a significant decrease until a stable level within 8 to 24 h in liver tissues of female rats due to surgery. Conclusion: The metabolism of lycopene in male rats is quicker than that in female rats. The metabolism of lycopene is related to female hormone level in rats, and the shortage of female hormone can promote the metabolism of lycopene in rats.

Key words: lycopene, metabolism, gender