Diweng Zhixie Power Ameliorates Dampness-Heat Diarrhea by Restoring Intestinal Microbiota Dysbiosis and Short-Chain Fatty Acids

Current therapeutics for diarrhea have limitations. Classical Formula Diweng Zhixie power (DW) is derived from Shang Han Lun and has a long history of treating gastrointestinal diseases such as diarrhea. Nevertheless, the exact mechanism of it needs to be further clarified. We aimed to investigate the treatment effect of DW on dampness-heat diarrhea in rats. HPLC quantified the bioactive components. Rats were assessed for weight, temperature, water intake, and diarrhea severity. Inflammation markers and protein pathways were analyzed via ELISA and Western blot. GC–MS measured cecal SCFAs, while 16S rRNA sequencing evaluated gut microbiota. The contents of esculin, jatrorrhizine, palmatine, berberine, esculetin, gallic acid, catechin, and anemoside B4 in DW were 0.134%, 0.165%, 0.046%, 0.30%, 0.099%, 0.309%, 0.312%, and 0.870%, respectively. DW alleviated dampness-heat diarrhea in rats and restored the intestinal microbiota dysbiosis. Furthermore, DW efficiently suppressed the abnormal inflammatory response and reduced the severity of pathological damage, restored the level of inflammatory factors, increased the expression of G-coupled protein and the content of SCFAs in the model group. The mechanisms by which DW protects against dampness-heat diarrhea may involve restoring goblet cell function, repairing intestinal microbiota dysbiosis, and modulating the inflammatory response, with GPCRs acting a critical role in the antidiarrhea effect of DW.