[Moxibustion at "Zusanli"(ST36) mitigates senescence in subacute aging rats via regulating SIRT1/p53 signaling pathway].

To observe the effect of moxibustion at "Zusanli"(ST36) on the silent information regulator 1 (SIRT1) /p53 signaling pathway in subacute aging model rats, so as to reveal its mechanisms in delaying aortic aging.Male SD rats were divided into blank group, model group, prevention group and treatment group, with 20 rats in each group. Subacute aging model was established by intraperitoneal injection of D-galactose(500 mg·kg-1·d-1). In the morning, rats in the prevention group received moxibustion at ST36 with 3 moxa cones after modeling operation, once every day for 42 d. From the day after the 42-day modeling, rats in the treatment group received the same moxibustion treatment as the prevent group for 28 d. Rats in the blank and model group were fixed in the similar way as the other two groups, for 5 min. Contents of serum SIRT1, p53, endothelial nitric oxide synthase(eNOS) and vascular endothelial growth factor(VEGF) were detected by ELISA. Histopathological changes of aortic tissue were observed after HE staining. Expressions of SIRT1 and p53 mRNAs and proteins in aortic tissue were detected by qPCR and Western blot.Compared with the blank group, the model group showed aging symptoms, the prevention group was similar to the blank group, and the treatment group was slightly better than the model group. Compared with the blank group, content of serum p53, expressions of p53 mRNA and protein in aortic tissues were significantly increased (P<0.05, P<0.01), while contents of serum SIRT1, VEGF, eNOS, and expressions of SIRT1 mRNA and protein in aortic tissues were significantly decreased (P<0.05, P<0.01) in the model group. Compared with the model group, content of serum p53, and expression of p53 mRNA and protein in aortic tissues were significantly decreased (P<0.05, P<0.01) in the prevention and treatment groups, while the contents of serum SIRT1, VEGF, eNOS, and the expressions of SIRT1 mRNA and protein in aortic tissues were significantly increased (P<0.05, P<0.01). Compared with the treatment group, rats in the prevention group displayed significant improvement of the above indexes (P<0.05). Compared with the blank group, the endothelial cells were disordered, the vessel wall was significantly thickened, and the senescent cells were increased in the model group; the blood vessel walls were thinner to varying degrees, and the senescent cells were reduced and unevenly distributed in the prevention and treatment groups. The histopathological lesion was improved more obviously in the prevention group than the treatment group.Moxibustion at ST36 can alleviate vascular endothelial injury and oxidative stress in subacute aging rats, which may be related to its effect in regulating the SIRT1/p53 signaling pathway.目的：观察艾灸“足三里”对亚急性衰老模型大鼠沉默信息调节因子1(SIRT1)/p53信号通路的影响，探讨SIRT1/p53通路在艾灸“足三里”延缓大鼠主动脉衰老中的作用机制。方法：SD大鼠分为空白组、模型组、预防组及治疗组，每组20只。以D-半乳糖溶液腹腔注射复制亚急性衰老模型。预防组每天上午造模后以艾炷灸“足三里”，每次灸3壮，每日1次，连续造模及治疗42 d。治疗组造模成功后次日开始“足三里”艾炷灸，每次灸3壮，每日1次，共治疗28 d。观察各组大鼠一般状况，ELISA法检测大鼠血清SIRT1、p53、血管内皮生长因子(VEGF)、内皮型一氧化氮合酶(eNOS)含量，HE染色法观察主动脉组织的衰老情况，荧光定量PCR法及Western blot法检测主动脉组织SIRT1、p53 mRNA及蛋白表达。结果：与空白组比较，模型组大鼠出现衰老症状，预防组一般状况与空白组接近，治疗组略好于模型组。与空白组比较，模型组大鼠血清p53含量升高(P<0.05)，SIRT1、VEGF、eNOS含量降低(P<0.05)；与模型组比较，预防组及治疗组大鼠血清p53含量降低(P<0.05)，SIRT1、VEGF、eNOS含量升高(P<0.05)；预防组较治疗组各指标变化更明显(P<0.05)。与空白组比较，模型组大鼠主动脉组织的SIRT1 mRNA及蛋白表达降低(P<0.01)，p53 mRNA和蛋白表达升高(P<0.01)；与模型组比较，预防组及治疗组大鼠的SIRT1 mRNA和蛋白表达升高(P<0.01)，p53 mRNA和蛋白表达降低(P<0.01)；预防组较治疗组各指标变化更明显(P<0.01)。与空白组比较，模型组大鼠主动脉组织内皮细胞排列紊乱，血管壁明显增厚，衰老细胞明显增多；预防组、治疗组的血管壁均有不同程度变薄，衰老细胞减少且分布不均匀，预防组略好于治疗组。结论：艾灸“足三里”延缓衰老的作用机制可能与激活血管内皮SIRT1，抑制p53的表达，从而影响 SIRT1/p53信号通路，降低细胞中活性氧的含量和增强对氧化损伤的保护作用有关。.