[Effect of moxibustion on acupoints at "opening" time on telomere length and expression of liver cell cycle regulators in aging rats].

Objective: To observe the effects of "lingguibafa" moxibustion performing at the appropriate acupoints at their "opening" time on telomere length，expressions of p53 of tumor supressor genes and retinoblastoma gene(Rb)in the liver of aging rats，so as to explore its mechanisms underlying delaying senescence.

Methods: Forty male SD rats were randomly divi-ded into normal, model, prevention and treatment groups, with 10 rats in each group. The rat model was established by intrape-ritoneally injection of D-galactose (200 mg/kg) once a day for 42 days. The rats in the prevention group were given "lingguibafa" moxibustion during modeling, while those in the treatment group were given "lingguibafa" moxibustion after modeling. Quantitative real-time PCR was used to detect the telomere length and the mRNA expressions of p53 and Rb，ELISA was used to detect the protein contents of p53 and Rb in the liver tissues.

Results: Compared with the normal group, the relative telomere length of the model group was significantly shortened (P<0.01), the mRNA expressions and protein contents of p53 and Rb were significantly increased (P<0.01). After intervention and in comparison with the model group, the relative telomere length of the prevention group and the treatments group were significantly increased (P<0.01), and the expressions of p53 and Rb mRNA and protein contents were significantly reduced (P<0.01, P<0.05). There were no significant difference between the prevention and the treatment groups in the abovementioned indexes (P>0.05).

Conclusion: Moxibustion on acupoints at "opening" time can inhibit the shortening of telomere length and the down-regulation of the expressions of p53 and Rb in aging rats, which may contribute to its function in delaying the process of cell senescence.