Screening the effective components in treating dampness stagnancy due to spleen deficiency syndrome and elucidating the potential mechanism of Poria water extract

Poria is an important medicine for inducing diuresis to drain dampness from the middle energizer.However,the specific effective components and the potential mechanism of Poria remain largely unknown.To identify the effective components and the mechanism of Poria water extract(PWE)to treat dampness stagnancy due to spleen deficiency syndrome(DSSD),a rat model of DSSD was established through weight-loaded forced swimming,intragastric ice-water stimulation,humid living environment,and alternate-day fasting for 21 days.After 14 days of treatment with PWE,the results indicated that PWE increased fecal moisture percentage,urine output,D-xylose level and weight;amylase,albumin,and total protein levels;and the swimming time of rats with DSSD to different extents.Eleven highly related components were screened out using the spectrum-effect relationship and LC-MS.Mechanistic studies revealed that PWE significantly increased the expression of serum motilin(MTL),gastrin(GAS),ADCY5/6,p-PKAα/β/γcat,and phosphorylated cAMP-response element binding protein in the stomach,and AQP3 expression in the colon.Moreover,it decreased the levels of serum ADH,the expression of AQP3 and AQP4 in the stomach,AQP1 and AQP3 in the duodenum,and AQP4 in the colon.PWE induced diuresis to drain dampness in rats with DSSD.Eleven main effective components were identified in PWE.They exerted therapeutic effect by regulating the AC-cAMP-AQP signaling pathway in the stomach,MTL and GAS levels in the serum,AQP1 and AQP3 expression in the duodenum,and AQP3 and AQP4 expression in the colon.

Modulating effects of Astragalus polysaccharide on immune disorders via gut microbiota and the TLR4/NF-κB pathway in rats with syndrome of dampness stagnancy due to spleen deficiency

The syndrome of dampness stagnancy due to spleen deficiency(DSSD)is relatively common globally.Although the pathogenesis of DSSD remains unclear,evidence has suggested that the gut microbiota might play a significant role.Radix Astragali,used as both medicine and food,exerts the effects of tonifying spleen and qi.Astragalus polysaccharide(APS)comprises a macromolecule substance extracted from the dried root of Radix Astragali,which has many pharmacological functions.However,whether APS mitigates the immune disorders underlying the DSSD syndrome via regulating gut microbiota and the relevant mechanism remains unknown.Here,we used DSSD rats induced by high-fat and low-protein(HFLP)diet plus exhaustive swimming,and found that APS of moderate molecular weight increased the body weight gain and immune organ indexes,decreased the levels of interleukin-1β(IL-1β),IL-6,and endotoxin,and suppressed the Toll-like receptor 4/nuclear factor-κB(TLR4/NF-κB)pathway.Moreover,a total of 27 critical genera were significantly enriched according to the linear discriminant analysis effect size(LEfSe).APS increased the diversity of the gut microbiota and changed its composition,such as reducing the relative abundance of Pseudoflavonifractor and Paraprevotella,and increasing that of Parasutterella,Parabacteroides,Clostridium XIVb,Oscillibacter,Butyricicoccus,and Dorea.APS also elevated the contents of short-chain fatty acids(SCFAs).Furthermore,the correlation analysis indicated that 12 critical bacteria were related to the body weight gain and immune organ indexes.In general,our study demonstrated that APS ameliorated the immune disorders in DSSD rats via modulating their gut microbiota,especially for some bacteria involving immune and inflammatory response and SCFA production,as well as the TLR4/NF-κB pathway.This study provides an insight into the function of APS as a unique potential prebiotic through exerting systemic activities in treating DSSD.