Effects of Aloin Gel Plaster on intestinal flora,MTL,VIP and SP levels in mice with constipation

CHEN Yizhuo; WANG Weiying; ZHANG Huawen; WU Fang; HUA Wei; ZHU Yanhua

doi:10.13506/j.cnki.jpr.2025.11.002

Abstract：Objective To study the effects of Aloin Gel Plaster on intestinal flora,motilin(MTL),vasoactive intestinal peptide(VIP),and substance P(SP)in constipation model rats.Methods Thirty SD rats were randomly assigned to a blank group,an oral group,a positive drug control group,a model group,and a gel plaster group(n=6),with a constipation model induced by loperamide at a dosage of 6 mg·(kg·d)-1.Two weeks after modeling,the blank group and the model group were administered with the plaster base applied to the umbilical region of the rats,covering an area of 3 × 3 cm.The oral group re-ceived a gavage of 2 mL of aloin aqueous solution(3 mg·mL-1)three times daily.The gel plaster group was administered with a self-made aloin gel plaster,while the positive drug control group was administered with Mitong Plaster,both with an applica-tion interval of once a day.After two weeks of administration,the levels of MTL,VIP,and SP in the serum were detected using the ELISA method.Additionally,PCR amplification was performed on rat feces,and the intestinal flora structure was analyzed through 16S rRNA sequencing technology.Results Compared to the blank control group,the model group exhibited signifi-cantly decreased serum levels of MTL and SP and increased VIP(P＜0.01).In contrast,the gel group,oral group,and positive control group showed elevated MTL and SP levels and reduced VIP levels compared to the model group(P＜0.01).Alpha di-versity analysis results showed that the Chao1 index,Observed species index,Shannon index,and Simpson index in the model group all showed a decreasing trend compared to the blank group(P＜0.01),while the gel group,oral group,and positive drug control group all showed an increasing trend compared to the model group(P＜0.01).The non-metric multidimensional scaling(NMDS)analysis of β diversity indicates that the fitted model is acceptable.At the phylum level,the analysis of gut microbiota shows that the gel group influenced the gut microbiota by increasing the abundance of Firmicutes and decreasing the abundance of Bacteroidetes,and the gel group improved the abundance of Firmicutes and reduced the abundance of Bacte-roidetes more effectively than the oral group,with effects similar to those of the positive control drug group.At the class level,the relative abundance of beneficial bacteria such as Lactobacillus and Bifidobacterium in all dosing groups was higher than in the model group.Additionally,all dosing groups exhibited inhibitory effects on Enterobacteriaceae.Among them,the oral group had a poorer inhibitory effect,while the gel group showed significant inhibitory effects.Conclusion The aloin gel plaster can improve the constipation symptoms by increasing the levels of SP and MTL,reducing the level of VIP,and increasing the rela-tive abundance of Firmicutes,Lactobacillales,and Bifidobacteriales,as well as decreasing the relative abundance of Bacte-roidetes and Enterobacteriales,to regulate the intestinal microecology.