Anti-diarrheal effect of piperine possibly through the interaction with inflammation inducing enzymes: In vivo and in silico studies.

Piperine is a natural alkaloid that possesses a variety of therapeutic properties, including anti-inflammatory, antioxidant, antibacterial, and anticarcinogenic activities. The present study aims to assess the medicinal benefits of piperine as an anti-diarrheal agent in a chick model by utilizing in vivo and in silico techniques. For this, castor oil was administered orally to 2-day-old chicks to cause diarrhea. Bismuth subsalicylate (10 mg/kg), loperamide (3 mg/kg), and nifedipine (2.5 mg/kg) were used as positive controls, while the vehicle was utilized as a negative control. Two different doses (25 and 50 mg/kg b.w.) of the test sample (piperine) were administered orally, and the highest dose was tested with standards to investigate the synergistic activity of the test sample. In our findings, piperine prolonged the latent period while reducing the number of diarrheal feces in the experimental chicks during the monitoring period (4 h). At higher doses, piperine appears to reduce diarrheal secretion while increasing latency in chicks. Throughout the combined pharmacotherapy, piperine outperformed bismuth subsalicylate and nifedipine in terms of anti-diarrheal effects with loperamide. In molecular docking, piperine exhibited higher binding affinities towards different inflammatory enzymes such as cyclooxygenase 1 (-7.9 kcal/mol), cyclooxygenase 2 (-8.4 kcal/mol), nitric oxide synthases (-8.9 kcal/mol), and L-type calcium channel (-8.8 kcal/mol), indicating better interaction of PP with these proteins. In conclusion, piperine showed a potent anti-diarrheal effect in castor oil-induced diarrheal chicks by suppressing the inflammation and calcium ion influx induced by castor oil.

Dietary nucleotides influences intestinal barrier function, immune responses and microbiota in 3-day-old weaned piglets.

Nucleotides (NTs) play a pivotal role in the growth and development of the intestine. This study aimed to evaluate the effects of nucleotides supplementation on the intestinal barrier function, immune responses and microbiota in 3-day-old weaned piglets. Ninety-six piglets weaned at 3-days after birth were randomly assigned to 2 treatments (6 replicates/treatment, 8 piglets/replicate) according to the average body weight. The dietary treatments consisted of the control (CON; fed a basal artificial milk) and nucleotides groups (NT; fed a basal artificial milk with 0.035 % nucleotides, the contents of CMP, UMP, AMP, GMP, and IMP were 1:1:1:1:1, respectively). Diarrhea rates were recorded, and blood and intestinal samples were collected on day 35 of the piglets. The current study showed that NTs supplementation tended to decrease the diarrhea rate of weaned piglets (P < 0.10). NTs increased villus height and the villus height-to-crypt depth (V/C) ratio in the ileum (P < 0.05). Dietary NTs up-regulated protein expression of ZO-1 in ileal mucosa (P < 0.05), and the protein expression of Occludin tended to increase. Furthermore, NTs up-regulated the mRNA expression of Mucin (MUC)2, while the mRNA expression of MUC4 was down-regulated in the ileal mucosa (P < 0.05). Besides, supplementation with NTs increased the ileal mucosa genes expression of IL-21, INF-γ, IL-10, IL-4, IL-6 and TNF-α (P < 0.05). Furthermore, dietary NTs increased the protein expression of NF-κB, IL-6 and TNF-α (P < 0.05), and the proteins expression of Occludin and p-NF-κB tended to be up-regulated in the ileal mucosa (P < 0.10). Furthermore, NTs supplementation increased short chain fatty acid in the colonic (P < 0.05). And NTs supplementation reduced the Firmicutes/Bacteroidota ratio in the colon, at the genus level, NTs enriched the relative abundance of Prevotella, Faecalibacterium and Olsenella (P < 0.05). These data indicate that NTs could increase the villus height, increase the V/C, regulate the expression of tight junction protein and mucin, improve the intestinal barrier of piglets, regulate the secretion of cytokines, improve the biological immunity, increase the abundance of beneficial bacteria, and thus reduce the diarrhea of piglets.

Effects of Nemacystus decipiens polysaccharide on mice with antibiotic associated diarrhea and colon inflammation.

Antibiotic associated diarrhea (AAD) is a common side effect of antibiotic therapy in which gut microbiota plays an important role in the disease. However, the function of gut microbiota in this disease is still not entirely clear. Polysaccharides have shown strong activity in shaping gut microbiota. Whether the polysaccharide can intervene with the microbiota to improve ADD has not been determined. In this study, we extract crude polysaccharides from Nemacystus decipiens (N. decipiens), a traditional Chinese medicine (TCM), named NDH0. The crude polysaccharide NDH0 might significantly relieve the symptom of mice with AAD, including a reduction in body weight, shortening of cecum index and the infiltration of inflammatory cells into the colon. NDH0-treated mice exhibited more abundant gut microbial diversity; significantly increased the abundance of Muribaculum, Lactobacillus, and Bifidobacterium and decreased the abundance of Enterobacter and Clostridioides at genus level. NDH0 treatment down-regulated the level of pro-inflammatory cytokines, including IL-1ß and IL-6 in colon tissue. NDH0 protected the integrity of colon tissues and partially inactivated the related inflammation pathway by maintaining occludin and SH2-containing Inositol 5'-Phosphatase (SHIP). NDH0 could alleviate symptoms of diarrhea by modulating gut microbiota composition, improving intestinal integrity and reducing inflammation. The underlying protective mechanism was to reduce the abundance of opportunistic pathogens and maintain SHIP protein expression. Collectively, our results demonstrated the role of NDH0 as a potential intestinal protective agent in gut dysbiosis.

Investigations of plausible pharmacodynamics supporting the antispasmodic, bronchodilator, and antidiarrheal activities of Berberis lycium Royle. Via in silico, in vitro, and in vivo studies.

ETHNOPHARMACOLOGICAL RELEVANCE: Berberis lycium Royle, a member of the Berberidaceae family, is a high-value medicinal plant with a documented history of usage in traditional medicine and has demonstrated significant therapeutic results among local populations throughout the globe. It is used traditionally in many parts of Pakistan to treat diarrhea, abdominal spasms, coughs, and chest problems. AIM OF THE STUDY: To investigate the antispasmodic, bronchodilator, and antidiarrheal effects of B. lycium and its possible underlying mechanisms through in silico, in vitro, and in vivo studies. MATERIALS AND METHODS: LC ESI-MS/MS analysis was used to identify bioactive components within the hydromethanolic extract of B. lycium. In silico studies, including network pharmacology and molecular docking, were utilized to investigate the antispasmodic and bronchodilator properties of the extract's bioactive components. In vitro pharmacological studies were conducted using isolated rabbit jejunum, trachea, urinary bladder, and rat ileum preparations. In vivo antidiarrheal activities were conducted in mice, including castor oil-induced diarrhea, intestinal transit, and castor oil-induced enteropooling. RESULTS: The LC ESI-MS/MS analysis of the hydromethanolic extract of B. lycium identified 38 bioactive compounds. Network pharmacology study demonstrated that the mechanism of BLR for the treatment of diarrhea might involve IL1B, TLR4, PIK3R1, TNF, PTPRC, IL2, PIK3CD, and ABCB1, whereas, for respiratory ailments, it may involve PIK3CG, TRPV1, STAT3, ICAM1, ACE, PTGER2, PTGS2, TNF, MMP9, NOS2, IL2, CCR5, HRH1, and VDR. Molecular docking research revealed that chlorogenic acid, epigallocatechin, isorhamnetin, quinic acid, gallic acid, camptothecin, formononetin-7-O-glucoside, velutin, caffeic acid, and (S)-luteanine exhibited a higher docking score than dicyclomine with validated proteins of smooth muscle contractions such as CACB2_HUMAN, ACM3_HUMAN, MYLK_HUMAN, and PLCG1_HUMAN. In vitro investigations demonstrated that Blr.Cr, Blr.EtOAc, and Blr.Aq relaxed spontaneously contracting jejunum preparations; carbachol (1 µM)-induced and K+ (80 mM)-induced jejunum, trachea, and urinary bladder contractions in a concentration-dependent manner, similar to dicyclomine. Moreover, Blr.Cr, Blr.EtOAc, and Blr.Aq exhibited a rightward shift in Ca+2 and carbachol cumulative response curves, similar to dicyclomine, demonstrating the coexistence of antimuscarinic and Ca+2 antagonistic mechanisms due to the presence of alkaloids and flavonoids. In vivo antidiarrheal activities showed that the hydromethanolic extract was significantly effective against castor oil-induced diarrhea and castor oil-induced enteropooling, similar to loperamide, and charcoal meal intestinal transit, similar to atropine, in mice at doses of 50, 100, and 200 mg/kg body weight, which supports its traditional use in diarrhea. CONCLUSION: The dual blocking mechanism of muscarinic receptors and Ca+2 channels behind the smooth muscle relaxing activity reveals the therapeutic relevance of B. lycium in diarrhea, abdominal spasms, coughs, and chest problems.

Deep-fried Atractylodes lancea rhizome alleviates spleen deficiency diarrhea-induced short-chain fatty acid metabolic disorder in mice by remodeling the intestinal flora.

ETHNOPHARMACOLOGICAL RELEVANCE: Atractylodes lancea (Thunb.) DC. is a Chinese herb that has been commonly used to treat spleen-deficiency diarrhea (SDD) in China for over a thousand years. However, the underlying mechanism of its antidiarrheal activity is not fully understood. AIM OF THE STUDY: The antidiarrheal effects of the ethanol extract of deep-fried A. lancea rhizome (EEDAR) due to spleen deficiency induced by folium sennae (SE) were determined on the regulation of the short-chain fatty acid (SCFA) metabonomics induced by the intestinal flora. MATERIALS AND METHODS: The effects of EEDAR on a SE-induced mouse model of SDD were evaluated by monitoring the animal weight, fecal water content, diarrhea-grade rating, goblet cell loss, and pathological changes in the colon. The expression of inflammatory factors (tumor necrosis factor [TNF]-α, interleukin [IL]-1ß, IL-6, IL-10), aquaporins (AQP3, AQP4, and AQP8), and tight junction markers (ZO-1, occludin, claudin-1) in colon tissues were determined using quantitative polymerase chain reaction and western blotting. SCFA metabonomics in the feces of mice treated with EEDAR was evaluated using gas chromatography-mass spectrometry. Furthermore, 16S rDNA sequencing was used to determine the effect of EEDAR on the intestinal flora of SDD mice, and fecal microbiota transplantation (FMT) was used to confirm whether the intestinal flora was essential for the anti-SDD effect of EEDAR. RESULTS: Treatment with EEDAR significantly improved the symptoms of mice with SDD by inhibiting the loss of colonic cup cells, alleviating colitis, and promoting the expression of AQPs and tight junction markers. More importantly, the effect of EEDAR on the increase of SCFA content in mice with SDD was closely related to the gut microbiota composition. EEDAR intervention did not significantly improve intestinal inflammation or the barrier of germ-free SDD mice, but FMT was effective. CONCLUSION: EEDAR alleviated SE-induced SDD in mice, as well as the induced SCFA disorder by regulating the imbalance of the intestinal microbiota.

Effects of dietary supplementation of bovine lactoferrin on growth performance, immune function and intestinal health in weaning piglets.

Weaning is a crucial period in the pig's life cycle, which is frequently followed by gastrointestinal (GI) infections, diarrhea and even death. This study focused on the impact of bovine lactoferrin (bLF) supplementation on the intestinal health of weaning piglets. Weaning piglets (Duroc × Landrace × Yorkshire, 23 days) were randomly allocated into four groups, which included negative control group (CON): basic diet; positive control group (ANT): basic diet + 20 mg/kg flavomycin + 100 mg/kg aureomycin; treatment group bLF-A: basic diet + 1 g/kg bLF; treatment group bLF-B: basic diet + 3 g/kg bLF. The result showed that dietary supplementation of bLF can improve growth performance and reduce diarrhea, which exhibits dose-dependency (P < 0.05). Compared with CON group, supplementation with bLF significantly improved immunity, and increased villus height and ratio of villus height/crypt depth at the small intestinal mucosa (P < 0.05). The mRNA expression of claudin-1, occludin and ZO-1 was greatly increased in the ileum of bLF group on days 7 and 14 (P < 0.05). Furthermore, the supplementation of bLF increased the abundance of Lactobacillus and Bifidobacterium and decreased the abundance of Escherichia coli in the cecum on day 7 (P < 0.05). The dietary supplementation of bLF enhanced the growth performance, reduced diarrhea rate in weaning piglets by improving intestinal immunity, morphology and barrier function, balancing intestinal microbiota. And bLF can be a promising feed additive in relieving stress situation of weaning piglets.

Increased expression of glucagon-like peptide-1 and cystic fibrosis transmembrane conductance regulator in the ileum and colon in mouse treated with metformin.

Metformin, an oral medication, is prescribed to patients with type 2 diabetes mellitus. Although the efficacy, safety, and low economic burden of metformin on patients have long been recognized, approximately 5% of the patients treated with this drug develop severe diarrhea and discontinue the treatment. We previously reported that 1,000 mg·kg-1·day-1 of metformin induced diarrhea in diabetic obese (db/db) mice and wood creosote (traditional medication for diarrhea) ameliorated the symptoms. In this study, we attempted to elucidate the molecular mechanisms by which metformin induces diarrhea. Cystic fibrosis transmembrane conductance regulator (CFTR) is a key ion (chloride) channel in cyclic adenosine monophosphate (cAMP)-induced diarrhea. Metformin treatment increased bile flow (bile acids and bilirubin) in the ileum of mice. In addition, the treatment was accompanied by an increase in mRNA and protein levels of CFTR in the mucosa of the ileum and colon in both wild-type (C57BL/6J) and db/db mice. Glucagon-like peptide-1 (GLP-1), as well as cholic acid, induces CFTR mRNA expression in human colon carcinoma Caco-2 cells through cAMP signaling. Although wood creosote (10 mg/kg) ameliorated diarrhea symptoms, it did not alter the mRNA levels of Glp-1 or Cftr. Similar to overeating, metformin upregulated GLP-1 and CFTR expression, which may have contributed to diarrhea symptoms in mice. Although we could not identify db/db mouse-specific factors associated with metformin-induced diarrhea, these factors may modulate colon function. Wood creosote may not interact with these factors but ameliorates diarrhea symptoms.

Vitamin A Ameliorated Irinotecan-Induced Diarrhea in a Piglet Model Involving Enteric Glia Modulation and Immune Cells Infiltration.

Vitamin A (VA) and its metabolite, retinoic acid (RA), play important roles in modulating intestinal mucosal immunity, yet little is known about their regulatory effects on enteric nervous system function. The study aims to explore the protective effects of dietary VA on diarrhea in a piglet model involving enteric glia and immune cell modulation. Twenty-eight weaned piglets were fed either the basal or VA (basal diet supplemented with 18,000 IU/kg VA) diet and with or without irinotecan (CPT-11) injection. CPT-11 induced increased diarrhea incidence, immune infiltration, and reactive enteric gliosis. A diet supplemented with 18,000 IU/kg VA ameliorated the adverse effects of CPT-11 on the gut barrier. VA reduced diarrhea incidence and attenuated enteric glial gliosis, immune cell infiltrations, and inflammatory responses of CPT-induced piglets. An in vitro experiment with 1 nmol/L RA showed direct protective effects on monocultures of enteric glial cells (EGCs) or macrophages in LPS-simulated inflammatory conditions. Furthermore, 1 ng/mL glial-derived neurotropic factors (GDNF) could inhibit M1-macrophage polarization and pro-inflammatory cytokines production. In summary, VA exerted protective effects on the intestinal barrier by modulating enteric glia and immune cells, perhaps enhancing epithelial recovery under CPT-11 challenge. Our study demonstrated that RA signaling might promote the roles of enteric glia in intestinal immunity and tissue repair, which provided a reference for the VA supplementation of patient diets.

The Effects of Patchouli Alcohol on Diarrhea-Predominant Irritable Bowel Syndrome are Correlated with Phenotypic Plasticity in Myenteric Neurons and the Targeted Regulation of Myosin Va.

Patchouli alcohol (PA) has been widely used for the treatment of diarrhea-predominant irritable bowel syndrome (IBS-D) in traditional Chinese medicine, and the related mechanism remains to be fully understood. Our previous study has indicated that PA significantly reduced visceral sensitivity and defecation area in IBS-D rats. In this study, we prepared an IBS-D rat model and observed the dynamic intestinal motility and colonic longitudinal muscle and myenteric plexus (LMMP) neurons, as well as their subtypes at D14, D21, and D28. After PA administration, we observed the effects on the changes in intestinal motility, colonic LMMP neurons, and LMMP Myosin Va in IBS-D rats and their co-localization with inhibitory neurotransmitter-related proteins. The results indicated that PA treatment could alleviate IBS-D symptoms, regulate the abnormal expression of LMMP neurons, increase Myosin Va expression, up-regulate co-localization levels of Myosin Va with neuronal nitric oxide synthase (nNOS), and promote co-localization levels of Myosin Va with vasoactive intestinal polypeptide (VIP). In conclusion, this study demonstrated the neuropathic alterations in the colon of chronic restraint stress-induced IBS-D rat model. PA reversed the neuropathological alteration by affecting the transport process of nNOS and VIP vesicles via Myosin Va and the function of LMMP inhibitory neurons, and these effects were related to the mechanism of enteric nervous system (ENS) remodeling.

Gegen Qinlian decoction restores the intestinal barrier in bacterial diarrhea piglets by promoting Lactobacillus growth and inhibiting the TLR2/MyD88/NF-κB pathway.

Acute bacterial diarrhea is a severe global problem with a particularly high incidence rate in children. The microecology inhabiting the intestinal mucosa is the key factor leading to diarrhea. Gegen Qinlian decoction (GQD) is used to treat bacterial diarrhea, however, its underlying mechanism remains unclear. Thus, this study aimed to clarify the restorative effect of GQD on the intestinal barrier from the perspective of gut microbiota. A Tibetan piglet model with bacterial diarrhea was established through orally administered Escherichia coli, and diarrheal piglets were treated with GQD for three days. After treatment, GQD significantly ameliorated the diarrheal symptoms. GQD decreased the levels of IL-6, LPS, and DAO, and increased SIgA, ZO-1, and occludin levels in intestinal mucosa, indicating the restoration of intestinal barrier. GQD modulated the microbial compositions inhabited on the intestinal mucosa, especially an increase of the Lactobacillus. Spearman analysis showed that Lactobacillus was the key genus of intestinal barrier-related bacteria. Bacterial culture in vitro validated that GQD directly promoted Lactobacillus growth and inhibited E. coli proliferation. Moreover, the expressions of TLR2, MyD88, and NF-κB in the colon decreased after GQD treatment. In conclusion, GQD may treat diarrhea and restore the intestinal mucosal barrier by facilitating Lactobacillus growth and inhibiting the TLR2/MyD88/NF-κB signaling pathway.

Antidiarrheal activity of the extracts of Valeriana jatamansi Jones on castor oil-induced diarrhea mouse by regulating multiple signal pathways.

ETHNOPHARMACOLOGICAL RELEVANCE: Valeriana jatamansi Jones, a traditional medicine, is used for various medicinal purposes worldwide. This species is popular for its gastro-protective properties and has been verified to exert antidiarrheal effects. Qiuxieling mixture, an oral liquid preparation used to treat diarrhea in children in clinical practice, was extracted from V. jatamansi Jones. AIM OF THE STUDY: Although Qiuxieling mixture has a good preventive effect on diarrhea children, the disgusting smell makes it intolerable. Therefore, we extracted odorless products from V. jatamansi Jones and Qiuxieling mixture. The present study is aimed to investigate the protective effects of two ethanolic extracts of V. jatamansi Jones and Qiuxieling mixture against castor oil-induced diarrhea and their possible mechanisms in mice. MATERIALS AND METHODS: The two extracts of V. jatamansi Jones and Qiuxieling mixture were detected by HPLC. A castor oil-induced diarrheal model was used to evaluate the antidiarrheal effects. The expression of Occludin in the small intestine was measured by IHC. Western blotting and immunofluorescence were used to detect the expression of proteins related to the oxidative stress and GSDMD-mediated pyroptosis signaling pathways. ELISA was used to detect the expression of IL-6 and IL-1ß in the small intestine of mice with diarrhea. RESULTS: The two extracts of V. jatamansi Jones and Qiuxieling mixture dose-dependently reduced the diarrhea index and the diarrhea rate, delayed the onset of diarrhea, and decreased the weight of the intestinal content. Meanwhile, they reversed the decreased expression of Occludin and restored the activity of Na+-K+-ATPase in the intestines of diarrheal mice. In addition, they reversed the depletion of GSH, attenuated the activation of the ERK/JNK pathway, promoted the Nrf2/SOD1 signaling pathways, and decreased the release of ROS in the intestines of diarrheal mice. Moreover, they suppressed GSDMD-mediated pyroptosis by downregulating the NLRP3/caspase-1/GSDMD signaling pathway. CONCLUSIONS: The two extracts of V. jatamansi Jones and Qiuxieling mixture exerted protective effects on castor oil-induced diarrhea in mice through a variety of mechanisms, including antioxidant stress, restoration of tight junctions between intestinal mucosal cells and regulation of the GSDMD-mediated pyroptosis pathway.

Hypericumsampsonii attenuates inflammation in mice with ulcerative colitis via regulation of PDE4/PKA/CREB signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Hypericum sampsonii Hance (Yuanbaocao), a traditional herbal medicine with various pharmacological properties, is traditionally used to treat diarrhea and enteritis in China for hundreds of years. Investigations have uncovered its anti-inflammatory effects and corresponding bioactive constituents in H. sampsonii, however, the mechanisms of action for the treatment of enteritis are still unclear. AIMS OF THE STUDY: This study aims to investigate the therapeutic effects and molecular mechanisms of H. sampsonii in a dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) mice model. MATERIALS AND METHODS: The major ingredients of the ethyl acetate extract (HS) in H. sampsonii were analyzed by UPLC-QTOF-MS. The inflammatory state of UC mice was caused by 3% DSS once daily for seven days. During DSS treatment, the mice in the positive drug group and the other three groups were orally administered 5-ASA (positive control) or HS daily. After treatment with HS or 5-ASA for a week, colonic pathological observation and the molecular biological index were performed for therapeutic evaluation, including visual inspection in the length and weight of colons and spleens, pathological morphology by hematoxylin and eosin (HE) staining, determination of oxidative markers, inflammatory cytokines and tumor necrosis factor-alpha (TNF-α) levels in colonic tissues as well as spleen index. Gene expression levels of inflammatory cytokines, antioxidant enzymes and PDE4 were detected using kits and PCR, while the expression of colonic tight junction proteins and relative signals of PKA/CREB signaling pathway were analyzed by Western blot. RESULTS: The main components in HS were found to be polycyclic polyprenylated acylphloroglucinols (PPAPs). HS distinctly alleviated DSS-stimulated UC-like lesions symptoms as evidenced by a significant recovery from body weight, colon lengths, and histological injuries of colons. HS reduced the accumulation of pro-inflammatory cytokines and improved the mRNA level of IL-10. Simultaneously, the colonic mRNA expression levels of IL-1ß, IL-17, iNOS and COX-2 were all significantly suppressed by HS in a dose-dependent manner. Furthermore, HS restored the protein expression of tight junction-associated protein (ZO-1 and occluding). Besides, HS significantly inhibited the protein level of PDE4 and decreased the expressions of PKA and phosphorylated CREB. CONCLUSION: This is the first work about main composition and anti-UC effect of Hypericum sampsonii Hance. For the first time, this study reveals HS is not toxic in a single dose and exert significantly protective effect in DSS-colitis mice. The underlying mechanisms may involve the improvement to inflammatory status, the protection for intestinal barrier function, the inhibition of PDE4, and the activation of PKA/CREB signaling pathway. This study provided an experimental basis for the traditional application of H. sampsonii Hance in the treatment of diarrhea and dysentery.

Panax quinquefolius Polysaccharides Ameliorate Antibiotic-Associated Diarrhoea Induced by Lincomycin Hydrochloride in Rats via the MAPK Signaling Pathways.

American ginseng (Panax quinquefolius L.) is an herbal medicine with polysaccharides as its important active ingredient. The purpose of this research was to identify the effects of the polysaccharides of P. quinquefolius (WQP) on rats with antibiotic-associated diarrhoea (AAD) induced by lincomycin hydrochloride. WQP was primarily composed of galacturonic acid, glucose, galactose, and arabinose. The yield, total sugar content, uronic acid content, and protein content were 6.71%, 85.2%, 31.9%, and 2.1%, respectively. WQP reduced the infiltration of inflammatory cells into the ileum and colon, reduced the IL-1ß, IL-6, IL-17A, and TNF-α levels, increased the levels of IL-4 and IL-10 in colon tissues, improved the production of acetate and propionate, regulated the gut microbiota diversity and composition, improved the relative richness of Lactobacillus and Bacteroides, and reduced the relative richness of Blautia and Coprococcus. The results indicated that WQP can enhance the recovery of the intestinal structure in rats, reduce inflammatory cytokine levels, improve short-chain fatty acid (SCFA) levels, promote recovery of the gut microbiota and intestinal mucosal barrier, and alleviate antibiotic-related side effects such as diarrhoea and microbiota dysbiosis caused by lincomycin hydrochloride. We found that WQP can protect the intestinal barrier by increasing Occludin and Claudin-1 expression. In addition, WQP inhibited the MAPK inflammatory signaling pathway to improve the inflammatory status. This study provides a foundation for the treatment of natural polysaccharides to reduce antibiotic-related side effects.

Potentilla discolor ameliorates LPS-induced inflammatory responses through suppressing NF-κB and AP-1 pathways.

Potentilla discolor Bunge (PD) is a traditional Chinese medicine which has been widely used for the treatment of various inflammatory diseases (e.g., diarrhea, fever and furuncle). However, few studies focused on its effect on classical inflammation. This study aimed to investigate the anti-inflammatory effect and potential mechanism of the ethanol extract of the whole herbs of PD (EPD) in lipopolysaccharide (LPS)-induced inflammatory models. The obtained results showed that EPD decreased supernatant NO, tumor necrosis factor-α (TNF-α) and monocyte chemoattractant protein-1 (MCP-1) in LPS-activated RAW264.7 cells and mouse peritoneal macrophages. Moreover, its effect on NO was attributed to the suppression of iNOS expression rather than its activity. At the transcriptional level, EPD suppressed iNOS, TNF-α and MCP-1 mRNA expressions in LPS-stimulated RAW264.7 cells. Further study showed that EPD didn't affect the phosphorylation and degradation of IκBα, but yet impeded the nuclear translocation of p65 to inhibit NF-κB activation. Meanwhile, it also prevented JNK, ERK1/2 and p38 phosphorylation to dampen the activation of AP-1. In endotoxemia mouse model, EPD not only decreased interleukin-6, TNF-α and MCP-1 levels in serum, but also potently ameliorated diarrhea. These findings provide the theoretical basis for PD to treat inflammatory diseases, especially intestinal inflammation.

Selenium-enriched Bifidobacterium longum DD98 attenuates irinotecan-induced intestinal and hepatic toxicity in vitro and in vivo.

Irinotecan (CPT-11) is a camptothecin chemotherapy drug largely used in treating cancers. However, its strong adverse effects, such as gastrointestinal and hepatic toxicities, tend to reduce the patients' life qualities and to limit the clinical use of CPT-11. The protective roles of selenium (Se) and probiotics against CPT-11-induced toxicity have been widely reported. However, the application of Se-enriched probiotics in the adjuvant therapy of CPT-11 has not been well explored. The purpose of this study is to evaluate the in-vitro and in-vivo effects of Se-enriched Bifidobacterium longum DD98 (Se-B. longum DD98) as a chemotherapy preventive agent on alleviating intestinal and hepatic toxicities induced by CPT-11 chemotherapy. The results showed that Se-B. longum DD98 positively regulated the aberrant cell viability and oxidative stress induced by CPT-11 both in human normal liver (L-02) and rat small intestinal epithelial (IEC-6) cell lines. In vivo experiment revealed that Se-B. longum DD98 significantly attenuated intestinal and hepatic toxicities by ameliorating symptoms such as body weight loss and diarrhea, and by improving the biochemical indicators of hepatotoxicity and oxidative stress. Furthermore, we discovered that the protective effects of Se-B. longum DD98 based largely upon decreasing the pro-inflammatory cytokines IL-1ß and IL-18 and enhancing the expression of tight-junction proteins occludin and ZO-1, as well as restoring the composition and diversity of gut microbiota. Results suggested that Se-B. longum DD98 effectively protected livers and intestines against the CPT-11-induced damages, and therefore, could be considered as a promising adjuvant therapeutic agent with CPT-11 for the cancer treatment.

Modified Renshen Wumei Decoction Alleviates Intestinal Barrier Destruction in Rats with Diarrhea.

Modified Renshen Wumei decoction (MRWD), a famous traditional Chinese medicine, is widely used for treating persistent diarrhea. However, as the mechanism by which MRWD regulates diarrhea remains unknown, we examined the protective effects of MRWD on intestinal barrier integrity in a diarrhea model. In total, 48 male rats were randomly distributed to four treatment groups: the blank group (CK group), model group (MC group), Medilac-Vita group (MV group) and Chinese herb group (MRWD group). After a 21-day experiment, serum and colon samples were assessed. The diarrhea index, pathological examination findings and change in D-lactate and diamine oxidase (DAO) contents illustrated that the induction of diarrhea caused intestinal injury, which was ameliorated by MV and MRWD infusion. Metabolomics analysis identified several metabolites in the serum. Some critical metabolites, such as phosphoric acid, taurine, cortisone, leukotriene B4 and calcitriol, were found to be significantly elevated by MRWD infusion. Importantly, these differences correlated with mineral absorption and metabolism and peroxisome proliferator-activated receptor (PPAR) pathways. Moreover, it significantly increased the expression levels of TLR4, MyD88 and p-NF-κB p65 proteins and the contents of IL-1 and TNF-α, while the expression levels of occludin, claudin-1 and ZO-1 proteins decreased. These deleterious effects were significantly alleviated by MV and MRWD infusion. Our findings indicate that MRWD infusion helps alleviate diarrhea, possibly by maintaining electrolyte homeostasis, improving the intestinal barrier integrity, and inhibiting the TLR4/NF-κB axis.

The mechanisms of action of WeiChang'An Pill (WCAP) treat diarrhoea-predominant irritable bowel syndrome (IBS-D) using network pharmacology approach and in vivo studies.

ETHNOPHARMACOLOGICAL RELEVANCE: WeiChang'An Pill (WCAP) is used in Traditional Chinese Medicine (TCM) to clinically treat diarrhoea-predominant irritable bowel syndrome (IBS-D); however, the underlying pharmacological mechanisms are unclear to date. AIM OF THE STUDY: To explore the mechanism underlying the therapeutic action of WCAP in IBS-D using a network pharmacology approach and in vivo experiments. MATERIALS AND METHODS: The active compounds of WCAP were selected from the TCM Systems Pharmacology Database and TCM Integrated Database, and the potential targets were identified using the Swiss Target Prediction and Similarity Ensemble Approach (SEA) databases. The targets related to IBS-D were mined from the Therapeutic Target Database (TTD), National Center for Biotechnology Information Search database (NCBI), DrugBank database, and DisGeNET database. The intersecting protein-protein interactions (PPIs) of the drug-disease crossover genes were analysed, and the central PPI network was constructed using the String database, version 11.0, and Cytoscape version 3.7.2. Following Gene Ontology and Kyoto Encyclopaedia of Genes and Genomes pathway analyses, the gene-pathway network was constructed for identifying the key target genes and pathways. Based on the results and existing evidence, it was selected the cyclic adenosine monophosphate (cAMP) signalling pathway for further validation using in vivo experiments. RESULTS: A total of 872 targets were identified from the 77 active compounds in WCAP, which shared 78 targets that were predicted to be related to IBS-D. Twenty-one core targets were identified from the PPI network, which was constructed from the common targets. The results of enrichment analysis revealed that HRT2B, ADRA1A, ADRA1D, and CHRM2 could be the key targets of WCAP in IBS-D, and 11 signalling pathways, including the neuroactive ligand-receptor interaction, calcium signalling, and cAMP signalling pathways, were identified as crucial for the therapeutic activity of WCAP in IBS-D. We also identified the possibility of several interactions and crosstalk between the different pathways. Subsequent molecular biology experiments revealed that the expression levels of cAMP, phospho-(Ser/Thr) protein kinase A substrates (p-PKA), 5-hydroxytryptamine, and proteins in the cAMP signalling pathway, including G protein-coupled receptor (GPCR), adenylyl cyclase 5 (AC5), and cAMP-response element binding protein (CREB), were significantly upregulated in rat models of IBS-D following treatment with WCAP (P < 0.05). However, a reverse trend was observed in the expression of nuclear factor kappa-B (NF-κB) (P < 0.05), which could be attributed to the low-grade inflammation that occurs in IBS-D. CONCLUSION: We demonstrated that WCAP may alleviate the symptoms of diarrhoea and visceral sensitivity in IBS-D by regulating the cAMP signalling pathway.

Anti-diarrheal therapeutic potential of diminazene aceturate stimulation of the ACE II/Ang-(1-7)/Mas receptor axis in mice: A trial study.

The angiotensin (Ang) II converting enzyme (ACE II) pathway has recently been shown to be associated with several beneficial effects on the body, especially on the cardiac system and gastrointestinal tract. ACE II is responsible for converting Ang II into the active peptide Ang-(1-7), which in turn binds to a metabotropic receptor, the Mas receptor (MasR). Recent studies have demonstrated that Diminazene Aceturate (DIZE), a trypanosomicide used in animals, activates the ACE II pathway. In this study, we aimed to evaluate the antidiarrheal effects promoted by the administration of DIZE to activate the ACE II/Ang-(1-7)/MasR axis in induced diarrhea mice models. The results show that activation of the ACE II pathway exerts antidiarrheal effects that reduce total diarrheal stools and enteropooling. In addition, it increases Na+/K+-ATPase activity and reduces gastrointestinal transit and thus inhibits contractions of intestinal smooth muscle; decreases transepithelial electrical resistance, epithelial permeability, PGE2-induced diarrhea, and proinflammatory cytokines; and increases anti-inflammatory cytokines. Enzyme-linked immunosorbent assay (ELISA) demonstrated that DIZE, when activating the ACE II/Ang-(1-7)/MasR axis, can still interact with GM1 receptors, which reduces cholera toxin-induced diarrhea. Therefore, activation of the ACE II/Ang-(1-7)/MasR axis can be an important pharmacological target for the treatment of diarrheal diseases.

Puerarin from Pueraria lobata alleviates the symptoms of irritable bowel syndrome-diarrhea.

As a functional bowel disorder, irritable bowel syndrome (IBS), especially IBS-diarrhea (IBS-D), affects approximately 9-20% of the population worldwide. Classical treatments for IBS usually result in some side effects and intestinal microbial disorders, which inhibit the clinical effects. Natural edible medicines with beneficial effects and few side effects have received more attention in recent years. Puerarin is the main active ingredient in pueraria and has been used in China to treat splenasthenic diarrhea and as a natural food in folk medicine for hundreds of years. However, there have been no reports of using puerarin in the treatment of IBS-D, and the underlying mechanism is also still unclear. In this study, a comprehensive model that could reflect the symptoms of IBS-D was established by combining neonatal maternal separation (NMS) and adult colonic acetic acid stimulation (ACAAS) in rats. The results showed that puerarin could reverse the abdominal pain and diarrhea in IBS-D rats. The therapeutic effect was realized by regulating the richness of the gut microbiota to maintain the stabilization of the intestinal micro-ecology. Furthermore, the possible mechanism might be related to the activity of the hypothalamic-pituitary-adrenal (HPA) axis by the suppressed expression of corticotropin-releasing hormone receptor (CRF) 1. At the same time, intestinal function was improved by enhancing the proliferation of colonic epithelial cells by upregulating the expression of p-ERK/ERK and by repairing the colonic mucus barrier by upregulating occludin expression. All these results suggest that puerarin could exert excellent therapeutic effects on IBS-D.

Correlation analysis between extracts and endogenous metabolites to characterise the influence of salt-processing on compatibility mechanism of 'Psoraleae Fructus & Foeniculi Fructus'.

ETHNOPHARMACOLOGICAL RELEVANCE: 'Salt-processed Psoraleae Fructus & salt-processed Foeniculi Fructus' (sPF&sFF) is a common Chinese medicinal combination for treating diarrhoea. However, it is not clear how sPF and sFF work together, and why salt-processing is necessary. AIM OF THE STUDY: To investigate the compatibility mechanism of sPF&sFF and the influence of salt-processing on it. MATERIALS AND METHODS: Firstly, the metabolomics approach was appliedto screen the differential components between four (s)PF&(s)FF extracts, i.e., sPF&sFF, sPF&FF, PF&sFF, and PF&FF extracts. Then, an in vivo metabolomics study was carried out to filter critical metabolites reflecting the curative effects of (s)PF&(s)FF, and construct a metabolic network. Finally, a correlation analysis between chemical components in extracts and critical metabolites in vivo was performed to find out the synergistic and/or antagonistic effects between herbs as well as the influence of salt-processing. RESULTS: Salt-processing had a direct influence on the contents of chemical components in sPF and sFF extracts, and there existed positive/negative correlations between the content change of chemical components and the effects of critical metabolites. Therefore, salt-processing indirectly affected on these correlations and was (i) conducive to the positive effects of sPF and sFF on bile acids, making sFF play a synergistic role, thereby, sPF&sFF could perform better than sPF and other three combinations and effectively relieve the symptoms of fatty diarrhoea, osmotic diuresis, malnutrition, and weight loss; (ii) conducive to the positive effects of sPF on triacylglycerol, 12(S)-hydroxyeicosatetraenoic acid, cholesterol, and arachidonic acid, and adverse to that of sFF, making sFF play an antagonistic role, thereby, sPF&sFF could prevent a series of side effects caused by over-regulation and suitably relieve the symptoms of osmotic diuresis, polyuria, malnutrition, and weight loss; and (iii) adverse to the positive effects of sPF and sFF on thromboxane A2, sphinganine and sphingosine, making sFF play a synergistic role, thereby, sPF&sFF could prevent a series of side effects and moderately relieve the symptoms of metabolic diarrhoea and polyuria. CONCLUSIONS: Salt-processing indirectly affected on the correlations between chemical components in extracts and critical metabolites in vivo, and exhibited both conducive and adverse effects on the efficacy, making sPF and sFF cooperate with each other to moderately repair the metabolic disorders. Thereby, sPF&sFF could suitably relieve the diarrhoea and polyuria symptoms in the model and exert the most appropriate efficacy. Moreover, this novel strategy provided a feasible approach for further studying the compatibility mechanism of herbs.