南珠粉对皮肤光老化小鼠肠道菌群的调节作用

Regulating effect of south pearl powder on intestinal flora in skin photoaging mice

目的 观察南珠粉对皮肤光老化小鼠肠道菌群的影响,探究南珠粉对皮肤光老化的作用机制。方法 将15只ICR小鼠随机分为正常组、模型组、南珠粉组,每组5只。模型组、南珠粉组小鼠采用长波紫外线(UVA)、中波紫外线(UVB)照射8周制备皮肤光老化模型,模型制备成功后,南珠粉组给予南珠粉膏剂外用4周。干预结束后收取小鼠粪便进行16S rDNA高通量测序,并对物种的相对丰度、Alpha多样性、Beta多样性、肠道菌群结构、环境因子关联性进行分析。结果模型组小鼠皮肤呈光老化状态,组织结构损伤严重;南珠粉组小鼠皮肤光老化状态明显减轻,接近于正常组。模型组Alpha多样性指数均较正常组明显降低(P均<0.05),南珠粉组Shannon指数、Simpson指数、Pielou’s evenness指数均明显高于模型组(P均<0.05)。Beta多样性指数分析显示,正常组与模型组相距最远,南珠粉组介于正常组与模型组之间。在门水平上,与正常组相比,模型组拟杆菌门、疣微菌目门丰度降低,厚壁菌门丰度升高,差异均有统计学意义(P均<0.05);与模型组相比,南珠粉组蓝细菌门丰度明显升高(P<0.05)。在属水平上,与正常组相比,模型组unidentified_S24-7菌属、瘤胃球菌属、柄杆菌属下调,unclassified_Bacillaceae菌属上调,差异均有统计学意义(P均<0.05);与模型组相比,南珠粉组unidentified_S24-7菌属、瘤胃球菌属、柄杆菌属上调,unclassified_Bacillaceae菌属下调,差异均有统计学意义(P均<0.05)。LEfSe分析发现毛螺菌属、梭菌目、噬纤维菌目、炭疽芽孢杆菌纲、噬冷菌属、环状菌科、瘤胃球菌科、丁酸菌属等在南珠粉组富集;环境因子关联分析显示,氧自由基(ROS)、丙二醛(MDA)活性和酪氨酸酶(TYR)含量与乳酸杆菌属、葡萄球菌属呈正相关(P均<0.05),与阿克曼氏菌属、普雷沃氏菌属、苏黎世杆菌属呈负相关(P均<0.05);超氧化物歧化酶(SOD)与过氧化氢酶(CAT)活性与阿克曼氏菌属、普雷沃氏菌属、苏黎世杆菌属呈正相关(P均<0.05),与乳酸杆菌属、葡萄球菌属呈负相关(P均<0.05)。PICRUSt功能预测发现,3组小鼠肠道菌群显著富集在氨基酸代谢、碳水化合物代谢、复制和修复、转录、翻译等功能通路,南珠粉组在蛋白酶体、光合作用、青霉素和头孢菌素的生物合成通路上更为显著。结论 皮肤光老化与肠道菌群结构改变相关,南珠粉可能通过调节小鼠肠道菌群物种丰度发挥治疗皮肤光老化的作用。

Objective It is to observe the effect of south pearl powder on the intestinal flora of mice with skin photoaging,and to investigate its mechanism.Methods Fifteen ICR mice were randomly divided into normal group,model group and south pearl powder group,with 5 mice in each group.The mice in the model group and south pearl powder group were irradiated by long-wave ultraviolet A(UVA)and medium-wave ultraviolet B(UVB)for 8 weeks to establish the models of skin photoaging.The south pearl powder group was treated with topical application of south pearl powder cream for 4 weeks after successful modeling.At the end of the intervention,the mouse feces were collected for 16S rDNA high-throughput sequencing and analysis of the relative abundance of species,alpha diversity,Beta diversity,gut flora structure,and environmental factor association.Results The skin of mice in the model group was photoaging,and the tissue structure was seriously damaged;the photoaging status of the skin of mice in the south pearl powder group was significantly relieved and close to that of the normal group.The Alpha diversity indexes of the model group were significantly lower than those of the normal group(all P<0.05),and the Shannon index,Simpson index and Pielou’s index of the south pearl powder group were significantly higher than those of the model group(all P<0.05).Beta diversity index analysis showed that the normal group was the furthest away from the model group,and the south pearl powder was between the normal group and the model group.At the level of phylum,compared with the normal group,the abundances of Bacteroidetes,Verrucomicrobiales were decreased,and the abundance of Firmicutes was increased in the model group,and the differences were statistically significant(all P<0.05);compared with the model group,the abundance of Cyanobacteria in the south pearl powder group was significantly increased(P<0.05).At the level of genus,compared with the normal group,the unidentified_S24-7,Ruminococcus,Caulobacter were down-regulated,while unclassified_Bacillaceae were up-regulated in the model group,the differences were statistically significant differences(all P<0.05);compared with the model group,the unidentified_S24-7,Ruminococcus,Caulobacter were up-regulated,while unclassified_Bacillaceae were down-regulated in the south pearl powder group,the differences were statistically significant differences(all P<0.05).LEfSe analysis revealed that Lachnospiraceae,Clostridiales,Cytophagales,Cyophagia,Algoriphagus,Cyclobacteriaceae,Ruminococcaceae and Butyricicoccus were enriched in the south pearl powder group;environmental factor correlation analysis showed that oxygen free radicals(reactive oxygen species,ROS),malondialdehyde(MOD)activity and(tyrosine,TYR)content were positively correlated with Lactobacillus and Staphylococcus(all P<0.05),and negative correlated with Akkermansia,Prevotella and Turicibacter(all P<0.05);the activities of superoxide dismutase(SOD)and catalase(CAT)were positively correlated with Akkermansia,Prevotella and Turicibacter(all P<0.05),and negative correlated with Lactobacillus and Staphylococcus(all P<0.05).PICRUSt functional predictions revealed that the intestinal floras of mice of the three groups were significantly enriched in functional pathways such as amino acid metabolism,carbohydrate metabolism,replication and repair,transcription,and translation,the enrich in biosynthesis pathways such as proteasomes,photosynthesis,penicillin,and cephalosporins were more significant in the south pearl powder group.Conclusion Skin photoaging is associated with structural changes in intestinal flora,and the mechanism of action of south pearl powder in treating skin photoaging in mice may be related to the regulation of intestinal flora species abundance.