普洱熟茶对D-半乳糖衰老模型小鼠肠道菌群的影响

以D-半乳糖（D-galactose，D-gal）皮下注射建立小鼠衰老模型，探究普洱熟茶对衰老小鼠抗氧化酶活力、小肠形态结构、肠道菌群多样性及肠道微生物结构变化等的影响。本实验将C57/BL6小鼠随机分为对照组、衰老组和普洱熟茶组，18 周后，对小鼠超氧化物歧化酶（superoxide dismutase，SOD）活力、谷胱甘肽过氧化物酶（glutathione peroxidase，GSH-Px）活力、丙二醛（malondialdehyde，MDA）含量、小肠组织病理和肠道菌群结构（16S rDNA高通量测序）变化进行检测分析。结果发现，D-gal致衰老小鼠SOD和GSH-Px活力显著降低，MDA含量显著升高（P＜0.05）；普洱熟茶显著提高衰老小鼠体内SOD和GSH-Px活力，显著降低MDA含量（P＜0.05）；在苏木素-伊红染色实验中，与对照组相比，衰老组小鼠绒毛长度、隐窝深度和肌层厚度显著降低（P＜0.05）；与衰老组相比，普洱熟茶组小鼠绒毛长度、隐窝深度和肌层厚度显著升高（P＜0.05）；利用高通量测序技术发现普洱熟茶干预改善了衰老小鼠肠道菌群结构，具体表现为拟杆菌门与厚壁杆菌门数量比值显著升高（P＜0.05），乳杆菌科和乳杆菌属相对丰度显著降低（P＜0.05），瘤胃菌科相对丰度显著升高（P＜0.05）。普洱熟茶在正常的3 倍高剂量条件下可改善衰老所致的肠道菌群结构失衡现象，有助于延缓衰老。

Effect of Ripe Pu-erh Tea on Intestinal Microorganisms in D-Galactose-Induced Aging Mice

The objective of the study is to investigate the effect of ripe Pu-erh tea on the antioxidant enzyme activity, the morphology of small intestine, and the diversity and structural change of intestinal flora in D-galactose-induced aging mice. In this study, C57/BL6 mice were randomly divided into a control group, an aging group and a ripe Pu-erh tea group. A mouse model of aging was created by subcutaneous injection of D-galactose. After 18 weeks of oral administration, the changes in the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), malondialdehyde (MDA) content, and small intestinal histopathology were evaluated and the intestinal flora structure was analyzed by 16S rDNA high-throughput sequencing. The results showed that SOD and GSH-Px activities were significantly decreased and MDA content was significantly increased in D-gal induced aging mice (P < 0.05). Compared to the aging and group, SOD and GSH-Px activities were significantly increased and MDA content was significantly decreased in the ripe Pu-erh tea group (P < 0.05). In the hematoxylin-eosin (HE) staining test, compared to the control group, the intestinal villus length, crypt depth and muscle layer thickness of mice were significantly decreased in the aging group (P < 0.05). After the intervention with ripe Pu-erh tea, the intestinal flora structure was improved compared to the aging mice (P < 0.05); the ratio of Bacteroidetes to Firmicutes was significantly increased (P < 0.05), the relative abundance of Lactobacillaceae and Lactobacillus was significantly decreased (P < 0.05), and the relative abundance of Ruminococcaceae was significantly increased (P < 0.05). In summary, we conclude that Pu-erh ripe tea can improve intestinal environmental disorders in D-gal induced aging mice at doses three times higher than the normal level, thereby delaying the aging process.