Preliminary Studies On Antiaging Effect Of Cysteamine

The objective of the present study was to investigate the effects of cysteamine on osteoporosis in ovariectomized rats and free radical scavenging in aging mice.This paper consists of two parts as follows:1. The preventive and therapeutical effect of cysteamine on osteoporosis in ovariectomized rats.120 three-month-old Sprague Dawley (SD) rats were assigned to four groups: sham-operated group (sham), ovariectomized group (ovx), cure group (cure) and prevent group (prevent). The prevent group were given 30mg/kg CT2000 for 6 months while the cure group were fed with basal diet for 3 months, then given 30mg/kg CT2000 supplemented diet for another 3 months. The results showed that the SS mRNA in hypothalamus decreased in both cure and prevent groups at the end of experiment. In cure group, the levels of serum growth hormone and [Ca24] were significantly increased, but no difference was found in bone mineral density.2. The effect of cysteamine and mercaptoethanol on scavenging of free radicals in aging mice.Two hundreds of one-year-old female ICR mice were randomly allocated into control group (infused daily with saline), and four experimental groups (infused daily with 15mg/kg and 100mg/kg of cysteamine, 10mg/kg and 100mg/kg of mercaptoethanol respectively. The mice were killed after 10 days. The results showed that all treatments significantly increased SOD activities (p<0.05) and deceased MDA concentration (p<0.05) in cerebral homogenate in rats, but not influenced SOD activities and MDA concentration in serum and liver homogenates. High-dose of cysteamine and mercaptoethanol significantly decreased serum levels of growth hormone, suggesting that cysteamine may inhibit secretion of growth hormone via other pathways, and mercaptoethanol may also inhibit secretion of growth hormone via the same mechanism since they have similar chemical structures.