Er Shen Wan extract reduces diarrhea and regulates AQP 4 and NHE 3 in a rat model of spleen-kidney Yang deficiency-induced diarrhea

Imperata cylindrica polysaccharide ameliorates intestinal dysbiosis and damage in hyperuricemic nephropathy

In this study, a combination of adenine and potassium oxonate was utilized to establish a hyperuricemic nephropathy (HN) mouse model, aiming to elucidate the effect through which Imperata Cylindrica polysaccharide (ICPC-a) ameliorates HN. In HN mice, an elevation in the abundance of Erysipelatoclostridium, Enterococcus, Prevotella, and Escherichia-Shigella was observed, whereas Lactobacillus and Bifidobacterium declined. Additionally, the systemic reductions in the levels of acetate, propionate, and butyrate, along with a significant increase in indole content, were noted. HN mice demonstrated intestinal barrier impairment, as evidenced by diminished mRNA expression of ZO-1, Occludin, and Claudin-1 and increased Mmp-9 levels. The pro-inflammatory factors IL-6, IL-17, TNF-α, IFN-γ, and COX-2 were overexpressed. Subsequent gavage intervention with ICPC-a markedly mitigated the inflammatory response and ameliorated colon tissue damage. ICPC-a effectively regulated the abundance of gut microbiota and their metabolites, including short-chain fatty acids (SCFAs), bile acids (BAs), and indole, promoting the correction of metabolic and gut microbiota imbalances in HN mice. These findings underscored the capacity of ICPC-a as a prebiotic to modulate gut microbiota and microbial metabolites, thereby exerting a multi-pathway and multi-targeted therapeutic effect on HN.

Sishen Wan enhances intestinal barrier function via regulating endoplasmic reticulum stress to improve mice with diarrheal irritable bowel syndrome

BACKGROUND

Diarrheal irritable bowel syndrome (IBS-D), characterized primarily by the presence of diarrhea and abdominal pain, is a clinical manifestation resulting from a multitude of causative factors. Furthermore, Sishen Wan (SSW) has demonstrated efficacy in treating IBS-D. Nevertheless, its mechanism of action remains unclear.

METHODS

A model of IBS-D was induced by a diet containing 45 % lactose and chronic unpredictable mild stress. Additionally, the impact of SSW was assessed by measuring body weight, visceral sensitivity, defecation parameters, intestinal transport velocity, intestinal neurotransmitter levels, immunohistochemistry, and transmission electron microscopy analysis. Immunofluorescent staining was used to detect the expression of Mucin 2 (MUC2) and Occludin in the colon. Western blotting was used to detect changes in proteins related to tight junction (TJ), autophagy, and endoplasmic reticulum (ER) stress in the colon. Finally, 16S rRNA amplicon sequencing was used to monitor the alteration of gut microbiota after SSW treatment.

RESULTS

Our study revealed that SSW administration resulted in reduced visceral sensitivity, improved defecation parameters, decreased intestinal transport velocity, and reduced intestinal permeability in IBS-D mice. Furthermore, SSW promotes the secretion of colonic mucus by enhancing autophagy and inhibiting ER stress. SSW treatment caused remodeling of the gut microbiome by increasing the abundance of Blautia, Muribaculum and Ruminococcus torques group.

CONCLUSION

SSW can improve intestinal barrier function by promoting autophagy and inhibiting ER stress, thus exerting a therapeutic effect on IBS-D.

Angelicin: A leading culprit involved in fructus Psoraleae liver injury via inhibition of VKORC1

ETHNOPHARMACOLOGICAL RELEVANCE

The adverse effects of Fructus Psoraleae (FP), especially liver injury, have attracted wide attention in recent years.

AIM OF THE STUDY

To establish a system to explore potential hepatotoxic targets and the chief culprit of liver injury based on clinical experience, network pharmacological method, molecular docking, and in vitro and in vivo experiments.

MATERIALS AND METHODS

Clinical applications and adverse reactions to FP were obtained from public literatures. Components absorbed in the blood were selected as candidates to search for potential active targets (PATs) of FP. Subsequently, potential pharmacological core targets (PPCTs) were screened through the "drug targets-disease targets" network. Non-drug active targets (NPATs) were obtained by subtracting the PPCTs from the PATs. The potential hepatotoxic targets (PHTs) of FP were the intersection targets obtained from Venn analysis using NPATs, hepatotoxic targets, and adverse drug reaction (ADR) targets provided by the databases. Then, potential hepatotoxic components and targets were obtained using the "NPATS-component" network relationship. Molecular docking and in vitro and in vivo hepatotoxicity experiments were performed to verify the targets and related components.

RESULTS

Overall, 234 NPATs were acquired from our analysis, and 6 targets were identified as PHTs. Results from molecular docking and in vitro and in vivo experiments showed that angelicin is the leading cause of liver injury in FP, and VKORC1 plays an important role.

CONCLUSION

The results indicate that six targets, especially VKORC1, are associated with the PHTs of FP, and angelicin is the leading culprit involved in FP liver injury via inhibition of VKORC1.

Exploration of the Potential Mechanism of Yujin Powder Treating Dampness-heat Diarrhea by Integrating UPLC-MS/MS and Network Pharmacology Prediction

BACKGROUND

Yujin powder (YJP) is a classic prescription for treating dampness-heat diarrhea (DHD) in Traditional Chinese Medicine (TCM), but the main functional active ingredients and the exact mechanisms have not been systematically studied.

OBJECTIVES

This study aimed to preliminarily explore the potential mechanisms of YJP for treating DHD by integrating UPLC-MS/MS and network pharmacology methods.

METHODS

Ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) technology was used to determine the ingredients of YJP. And then, the targets of these components were predicted and screened from TCMSP, SwissTargetPrediction databases. The disease targets related to DHD were obtained by using the databases of GeneCards, OMIM, DisGeNET, TTD, and DrugBank. The protein-protein interaction networks (PPI) of YJP-DHD were constructed using the STRING database and Origin 2022 software to identify the cross-targets by screening the core-acting targets and a network diagram by Cytoscape 3.8.2 software was also constructed. Metascape database was used for performing GO and KEGG enrichment anlysis on the core genes. Finally, molecular docking was used to verify the results with AutoDock 4.2.6, AutoDock Tools 1.5.6, PyMOL 2.4.0, and Open Babel 2.3.2 software.

RESULTS

597 components in YJP were detected, and 153 active components were obtained through database screening, among them the key active ingredients include coptisine, berberine, baicalein, etc. There were 362 targets treating DHD, among them the core targets included TNF, IL-6, ALB, etc. The enriched KEGG pathways mainly involve PI3K-Akt, TNF, MAPK, etc. Molecular docking results showed that coptisine, berberine, baicalein, etc., had a strong affinity with TNF, IL-6, and MAPK14. Therefore, TNF, IL-6, MAPK14, ALB, etc., are the key targets of the active ingredients of YJP coptisine, baicalein, and berberine, etc. They have the potential to regulate PI3K-Akt, MAPK, and TNF signalling pathways. The component-target-disease network diagram revealed that YJP treated DHD through the effects of anti-inflammation, anti-diarrhea, immunoregulation, and improving intestinal mucosal injury.

CONCLUSION

It is demonstrated that YJP treats DHD mainly through the main active ingredients coptisine, berberine, baicalein, etc. comprehensively exerting the effects of anti-inflammation, anti-diarrhea, immunoregulation, and improving intestinal mucosal injury, which will provide evidence for further in-depth studying the mechanism of YJP treating DHD.

Ameliorative effect of Aconite aqueous extract on diarrhea is associated with modulation of the gut microbiota and bile acid metabolism

Introduction: Aconite is a form of traditional Chinese medicine (TCM) that has been widely used to treat diarrhea for thousands of years. However, it is not clear whether the anti-diarrhea role of aconite aqueous extract (AA) is associated with regulation of the gut microbiota or with bile acid (BA) metabolism. This study aimed to confirm whether AA exerts its anti-diarrhea effects by regulating the gut microbiota and BA metabolism. Methods: The therapeutic effect of AA in a mouse model of diarrhea was measured based on analysis of body weight, fecal water content, diarrhea scores, intestinal propulsion rate, colonic pathology, and colonic immunohistochemistry. In addition, 16S rRNA high-throughput sequencing was conducted to analyze the effect of AA on the gut microbiota, and targeted metabolomics was employed to analyze the effect of AA on metabolism of BAs. Results: The results showed that treatment with AA reduced fecal water content and diarrhea scores, inhibited intestinal propulsion rate and pathological changes in the colon, and increased AQP3 and AQP4 content in the colon. In addition, AA was found to be capable of regulating the gut microbiota. Effects included increasing its richness (according to the ACE and Chao1 indices); altering the gut microbiota community structure (PCA, PCoA, and NMDS); increasing the relative abundance of norank_f_Muribaculaceae, Ruminococcus, Lachnospiraceae_NK4A136_group, Prevotellaceae_UCG-001, and norank_f_norank_o_Clostridia_UCG-014; and decreasing the relative abundance of Escherichia-Shigella, unclassified_f_Ruminococcaceae, Ruminococcus_torques_group, and Parasutterella. More importantly, AA significantly increased fecal TCA (a primary BA) and DCA, LCA, GDCA, dehydro-LCA, and 12-keto-LCA (secondary BAs), thus restoring BA homeostasis. Moreover, AA increased the ratios of DCA/CA, DCA/TCA, and LCA/CDCA and decreased the ratios of TLCA/LCA, GLCA/LCA, and TUDCA/UDCA. Conclusion: The anti-diarrhea effect of AA was associated with restoration of the gut microbiota and BA metabolism-related homeostasis. The results of this study provide insights into the application of AA and the treatment of diarrhea.

Effects of different dietary protein levels on intestinal aquaporins in weaned piglets

This study was conducted to investigate the relationship between changes in intestinal aquaporins (AQPs) in piglets fed diets with different protein levels and nutritional diarrhoea in piglets. Briefly, 96 weaned piglets were randomly divided into four groups fed diets with crude protein (CP) levels of 18%, 20%, 22% and 24%. The small intestines and colons of the weaned piglets were collected, and several experiments were conducted. In the small intestine, AQP4 protein expression was higher in weaned piglets fed the higher-CP diets (22% and 24% CP) than in those fed the 20% CP diet except at 72 h (p < 0.01). At 72 h, the AQP4 protein expression in the small intestine was lower in the 18% group than in the other three groups (p < 0.01). Under 20% CP feeding, AQP2, AQP4 and AQP9 protein expression in the colons of piglets peaked at certain time points. The AQP2 and AQP4 mRNA levels in the colon and the AQP4 and AQP4 mRNA levels in the distal colon were approximately consistent with the protein expression levels. However, the AQP9 mRNA content in the colon was highest in the 18% group, and the AQP2 mRNA content in the distal colon was significantly higher in the 24% group than in the 20% group. AQP2 and AQP4 were expressed mainly around columnar cells in the upper part of the smooth colonic intestinal villi, and AQP9 was expressed mainly on columnar cells and goblet cells in the colonic mucosa. In conclusion, 20% CP is beneficial to the normal expression of AQP4 in the small intestine, AQP2, AQP4 and AQP9 in the colon of weaned piglets, which in turn maintains the balance of intestinal water absorption and secretion in piglets.

Seasonal differences in intestinal flora are related to rats' intestinal water metabolism

Many studies have reported obvious seasonal differences in the intestinal flora of rats, and this stable distribution of the seasonal flora helps in maintaining the normal physiological function of the host. However, the mechanism underlying these seasonal differences in intestinal flora remains unclear. To explore the correlation among seasonal factors and intestinal water metabolism and intestinal flora, 20 Sprague Dawley (SD) rats were divided into spring, summer, autumn, and winter groups. The environment for the four seasons was simulated using the Balanced Temperature and Humidity Control system. The intestinal water metabolism was evaluated by determining the intestinal transmission function, fecal water content, water content of colonic tissue, and the colonic expression levels of AQP3, AQP4, and AQP8. The composition and relative abundance of intestinal microflora in rats in each season were assessed through 16S rDNA amplifier sequencing, and the relationship between the dominant flora and intestinal water metabolism in each season was analyzed using Spearman correlation analysis. The high temperature and humidity season could lead to an increase in intestinal water metabolism and intestinal water content in rats, whereas the low temperature and humidity season could lead to a decrease, which was closely related to the change in microflora. To explore the molecular mechanism of seasonal changes in intestinal water metabolism, the concentration of colonic 5-HT, VIP, cAMP, and PKA associated with intestinal water metabolism in rats were also examined. Seasonal changes could affect the concentration of colonic 5-HT and VIP in rats, and then regulate AQPs through cAMP/PKA pathway to affect the intestinal water metabolism. These results suggest that seasonal factors affect the level of intestinal water metabolism in rats and result in seasonal differences in intestinal flora.

Differential proteomic of plasma provides a new perspective on scientific diagnosis and drug screening for dampness heat diarrhea in calves

Dampness heat diarrhea (DHD) is one of the most common syndromes of calf diarrhea. Its complex etiology and lack of objective diagnostic criteria bring great challenges to the diagnosis and treatment of this disease. This study aims to screen some prospective diagnostic biomarkers or therapeutic targets for calves with DHD by investigating the differential protein profiles of plasma between DHD calves and clinically healthy calves by mass spectrometry-based proteomic. A total of 120 DHD calves and 90 clinically healthy calves were divided into two groups randomly, 30 DHD calves and 30 clinically healthy calves in the test group, and 90 DHD calves and 60 clinically healthy calves in the validation group. In the test group, a total of 52 proteins were differentially expressed between calves with DHD and clinically healthy calves, 13 proteins were significantly increased and 39 proteins were significantly decreased. The differentially expressed proteins were associated with the intestinal immune network of IgA production, caffeine metabolism, purine metabolism, and PI3K signaling pathway. In the validation group, 13 proteins were selected from 52 differential expression proteins for parallel reaction monitoring validation to verify their associations with DHD calves. The targeted proteomic results showed that fibronectin precursor (FN1) and apolipoprotein C-IV precursor (APOC4) were significantly associated with DHD in calves, and they were downregulated in sick calves. In conclusion, the differential expression of plasma proteins was associated with DHD pathogenesis in calves, and the FN1 and APOC4 might be the potential clinical biomarkers for diagnosis of DHD in calves, and the intestinal immune network of IgA production, caffeine metabolism, purine metabolism, and PI3K signaling pathway are the candidate targets to treat DHD in calves. Our finding provides a reference for further investigating the pathogenesis, developing techniques of diagnosis, and screening treatment drugs for DHD in calves.

Shen-Ling-Bai-Zhu-San (SL) and SL Derived-Polysaccharide (PL) Ameliorate the Severity of Diarrhea-Induced by High Lactose via Modification of Colonic Fermentation

In our previous study, we demonstrated that Shen-ling-bai-zhu-san (SL), a classical Chinese herbal formula, could alleviate lactose-induced diarrhea. However, little is known about the mechanism underlying SL action or the efficacy of the polysaccharide (PL) derived from SL. In this study, we investigated the effect of SL and PL on improving the dysregulated luminal and mucosal microbiota in rats with high lactose diet using 16S rRNA analysis. The concentrations of lactose, lactic acid in cecum and short-chain fatty acids (SCFAs) in cecum and portal vein were measured, meanwhile the expression of ion transporters were ascertained. Our data suggest that the SL, PL and cecal microbiota transplantation (CMT) significantly decreased fecal water content and water intake. In the luminal microbiota there was a significant increase in Akkermansia, Bifidobacterium and Blautia and a lower abundance of Lactobacillus, Escherichia-Shigella, and Dubosiella, while the mucosal microbiota showed a significant increase in Bifidobacterium, Akkermansia, Albaculum, Bilophila, and Coriobacteriaceae_UCG-002 and a lower abundance of Enterococcus, Helicobacter, Dubosiella, and Collinsella. Furthermore, the treatments enhanced lactose fermentation and SCFA production, which may be related to the modulation of the luminal microbial community. A lower ratio of phosphorylation Na/H exchanger3/Na/H exchanger3 (pNHE3/NHE3) and a higher sodium monocarboxylate1 (sMCT1) expression were found in the treatment group than in the model group, which may be related to the changes in the mucosal microbial community. Also, the treatments may restore the impacted metabolic pathways of gut microbiota. These results provide an important foundation for mechanism of SL action and developing PL-based treatment for lactose-induced diarrhea.

Integrated 16S rDNA Gene Sequencing and Untargeted Metabolomics Analyses to Investigate the Gut Microbial Composition and Plasma Metabolic Phenotype in Calves With Dampness-Heat Diarrhea

Dampness-heat diarrhea (DHD), a common syndrome in Chinese dairy farms, is mainly resulted from digestive system disorders, and accompanied with metabolic disorders in some cases. However, the underlying mechanisms in the intestinal microbiome and plasma metabolome in calves with DHD remain unclear. In order to investigate the pathogenesis of DHD in calves, multi-omics techniques including the 16S rDNA gene sequencing and metabolomics were used to analyze gut microbial compositions and plasma metabolic changes in calves. The results indicated that DHD had a significant effect on the intestinal microbial compositions in calves, which was confirmed by changes in microbial population and distribution. A total of 14 genera were changed, including Escherichia-Shigella, Bacteroides, and Fournierella, in calves with DHD (P < 0.05). Functional analysis based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) annotations indicated that 11 metabolic functions (level 2) were significantly enriched in DHD cases. The untargeted metabolomics analysis showed that 440 metabolites including bilineurin, phosphatidylcholine, and glutamate were significantly different between two groups (VIP > 1 and P < 0.05), and they were related to 67 signal pathways. Eight signal pathways including alpha-linolenic acid, linoleic acid, and glycerophospholipid metabolism were significantly enriched (P < 0.05), which may be potential biomarkers of plasma in calves with DHD. Further, 107 pairs of intestinal microbiota-plasma metabolite correlations were determined, e.g., Escherichia-Shigella was significantly associated with changes of sulfamethazine, butyrylcarnitine, and 14 other metabolites, which reflected that metabolic activity was influenced by the microbiome. These microbiota-metabolite pairs might have a relationship with DHD in calves. In conclusion, the findings revealed that DHD had effect on intestinal microbial compositions and plasma metabolome in calves, and the altered metabolic pathways and microorganisms might serve as diagnostic markers and potential therapeutic targets for DHD in calves.

Berberine Attenuates Arterial Plaque Formation in Atherosclerotic Rats with Damp-Heat Syndrome via Regulating Autophagy

Purpose

Berberine (BBR) is an effective component of Huanglian and has shown to attenuate atherosclerosis (AS); however, the detailed mechanism of BBR-mediated protective actions against AS remains elusive. This study was undertaken to examine the effects of BBR on aortic atherosclerotic plaque stability and the expression of autophagy-related proteins in AS rats with damp-heat syndrome or yang deficiency.

Methods

Thirty SD rats were randomly divided into (1) control (CON); (2) damp-heat syndrome atherosclerosis (AS + DH); (3) yang deficiency syndrome atherosclerosis (AS + YX); (4) damp-heat syndrome atherosclerosis + BBR (AS + DH + BBR); (5) yang deficiency syndrome, atherosclerosis + BBR (AS + YX + BBR); and (6) damp-heat syndrome, atherosclerosis + BBR + 3-methyladenine (AS + DH + BBR + 3-MA) (n = 5/group) groups. Pathological morphology, macrophage plaque infiltration, inflammation, and LC3-II and P62 expression were assessed.

Results

Compared with the CON group, the AS + DH and AS + YX groups had an increased plaque area in the aortic tissue with substantial foam cell and macrophage infiltration, and increased levels of IL-1β and TNF-α (P < 0.01). After four weeks of BBR intervention, the plaque area in the AS + DH + BBR group was reduced with decreased foam cells and macrophage infiltration, and decreased levels of TNF-α and IL-1β, whereas LC3-II protein expression was increased and P62 protein expression was decreased in the AS + DH + BBR group when compared to AS + DH group. In addition, the AS + DH + BBR + 3-MA group exhibited a significantly enlarged plaque, substantial foam cell and macrophage infiltration, increased levels of IL-1β and TNF-α, and decreased LC3-II and P62 (P < 0.01) expression when compared to the AS + DH + BBR group.

Conclusion

Our results indicated that the BBR could inhibit arterial plaque formation and alleviate the inflammatory response in the aortic tissues in the AS rats with damp-heat syndrome possibly via promoting autophagy. The molecular mechanisms of BBR-mediated protective effects in this animal model still require further investigation.

Pulsatilla Decoction Can Treat the Dampness-Heat Diarrhea Rat Model by Regulating Glycerinphospholipid Metabolism Based Lipidomics Approach

Ethnopharmacological Relevance

Diarrhea is a major medical problem in clinical practice. According to the theory of traditional Chinese medicine (TCM), different types of diarrhea should be treated with different TCM formulations based on the targeted medical condition. Dampness-heat diarrhea (DHD) is a serious diarrheal disease and Pulsatilla decoction (PD), a TCM, has been found effective against DHD.

Objective

The aim of this study was to clarify the mechanism of action of PD in DHD using an untargeted lipidomics strategy.

Materials and Methods

Wistar rats were randomized to four groups, including the control group, model group, PD groups and self-healing group. The PD groups were given a daily intragastric gavage of PD at doses of 3.76 g/kg. The rat model of DHD established by such complex factors as high-sugar and high-fat diet, improper diet, high temperature and humidity environment, drinking and intraperitoneal injection of Escherichia coli., which imitated the inducing conditions of DHD. Then the clinical symptoms and signs, blood routine, serum inflammatory cytokines levels and the histopathological changes of main organs were detected and observed to evaluate DHD model and therapeutic effect of PD. Lipid biomarkers of DHD were selected by comparing the control and model groups with the colon lipidomics technology and an ultra-high performance liquid chromatography (UHPLC) coupled with Q Exactive plus mass analyzer. Multivariate statistical analysis and pattern recognition were employed to examine different lipids within the colon of PD-treated rats.

Results

The clinical symptoms and signs of the model rats were consistent with the diagnostic criteria of DHD. After treatment with PD, the clinical symptoms and signs of the rats with DHD were improved; the indexes of blood routine and inflammatory cytokines levels tended to be normal. The lipidomics profile of the model group were evidently disordered when compared to the control group. A total of 42 significantly altered lipids between the model-control groups were identified by multivariate statistical analysis. DHD may result from such lipid disorders which are related to glycerophospholipid metabolism, arachidonic acid (AA) metabolism, and sphingolipid metabolism. After PD treatment, the lipidomic profiles of the disorders tended to recover when compared to the model group. Twenty lipid molecules were identified and some glycerophospholipids and AA levels returned close to the normal level.

Conclusion

Glycerophospholipid metabolism may play an important role in the treatment of dampness-heat induced diarrhea using PD.

Metabolomics analysis of Pulsatilla decoction on treatment of wetness-heat-induced diarrhea in rats based on UPLC-Q/TOF-MS/MS

Pulsatilla decoction (PD) is a classical prescription in traditional Chinese medicine that has therapeutic effects on wetness-heat-induced diarrhea (WHD). To investigate the therapeutic effects of PD in the treatment of WHD and elucidate the potential mechanism, we used a metabolomics strategy on the base of ultraperformance liquid chromatography coupled with quadrupole time-of-flight/mass spectrometry (UPLC-Q/TOF-MS/MS) and analyzed the serum samples of 32 rats to identify differential metabolites and pathways associated with the PD treatment of WHD. With variable importance for projection >1.0 in the Orthogonal partial least-squares discriminant analysis (OPLS-DA ) models and FC ≥1.2 or ≤0.8, 67 differential metabolites in the model and control groups and 33 differential metabolites in the model and PD groups were screened. A total of 23 differential metabolites were selected based on Venny analysis. Functional analysis showed that the differential metabolites identified were primarily involved in pentose and glucuronate interconversions, glycerophospholipid metabolism, tryptophan metabolism, starch and sucrose metabolism, and glycerolipid metabolism. This study suggested that PD exerts inhibitory effects on WHD. In particular, the significant roles of PD for treating WHD lie in regulating perturbed energy metabolism, glycerophospholipid metabolism and glycerolipid metabolism, and promoting lysoPC production restoring the function of intestinal tract.

Er Shen Wan extract alleviates polyuria and regulates AQP 2 and AVPR 2 in a rat model of spleen-kidney Yang deficiency-induced diarrhea

ETHNOPHARMACOLOGICAL RELEVANCE

Er Shen Wan (ESW), has been empirically used for treating spleen-kidney Yang deficiency (SKYD) syndrome in Traditional Chinese medicine (TCM) for centuries and shows a variety of activities. The medicinal formula is a mixture of two component herbs, Psoraleae Fructus (PF, Bu-Gu-Zhi in Chinese) and Myristicae Semen (MS, Rou-Dou-Kou in Chinese). The current study was designed to evaluate ESWP antidiuretic treatment of polyuria and to explore potential mechanisms of renal water metabolism in the rat model of SKYD-induced diarrhea.

MATERIALS AND METHODS

An animal model of 'SKYD-induced diarrhea syndrome' has been established to evaluate the therapeutic effect and action mechanism according to the clinical syndrome and symptoms. The optimal dose (3.5 g/kg) of ESWP was given to rats by gavage for two weeks. Urinary volumes after 24 h were recorded. After the end of the trial, macroscopic morphological and histological examination of the kidney were conducted. Serum levels of Arginine vasopressin (AVP) and aldosterone (ALD) were also measured. Additionally, quantitative real-time RT-PCR (RT-qPCR) and immunohistochemistry (IHC) analyses were performed to clarify the regulation of aquaporin 2 (AQP 2) and arginine vasopressin type 2 receptor (AVPR 2) in the kidney at the gene and tissue expression levels respectively.

RESULTS

After the administration of ESWP, urinary output volume after 24 h was found to be significantly decreased in rats. Elevated plasma levels of AVP and ALD were detected. Histological kidney damage appeared to be impeded, and histological disease scores were reduced. In addition, the expression levels of AQP 2 and AVPR 2 were significantly increased.

CONCLUSION

This study suggests that ESWP may elicit significant effects on the treatment of polyuria. Potential mechanisms at least partially involve hormone regulation, and alleviating renal pathological damage. Simultaneously, ESWP may alter renal water absorption by increasing AQP 2 and AVPR 2 expression levels. Thus, the in vivo experimental evidence indicates that ESWP has a therapeutic effect on the SKYD syndrome, which is consistent with its traditional usage.