Effects of elafibranor on liver fibrosis and gut barrier function in a mouse model of alcohol-associated liver disease

BACKGROUND Alcohol-associated liver disease(ALD)is a leading cause of liver-related morbidity and mortality,but there are no therapeutic targets and modalities to prevent ALD-related liver fibrosis.Peroxisome proliferator activated receptor(PPAR)α and δ play a key role in lipid metabolism and intestinal barrier homeostasis,which are major contributors to the pathological progression of ALD.Meanwhile,elafibranor(EFN),which is a dual PPARαand PPARδagonist,has reached a phase III clinical trial for the treatment of metabolic dysfunctionassociated steatotic liver disease and primary biliary cholangitis.However,the benefits of EFN for ALD treatment is unknown.AIM To evaluate the inhibitory effects of EFN on liver fibrosis and gut-intestinal barrier dysfunction in an ALD mouse model.METHODS ALD-related liver fibrosis was induced in female C57BL/6J mice by feeding a 2.5% ethanol(EtOH)-containing Lieber-DeCarli liquid diet and intraperitoneally injecting carbon tetrachloride thrice weekly(1 mL/kg)for 8 weeks.EFN(3 and 10 mg/kg/day)was orally administered during the experimental period.Histological and molecular analyses were performed to assess the effect of EFN on steatohepatitis,fibrosis,and intestinal barrier integrity.The EFN effects on HepG2 lipotoxicity and Caco-2 barrier function were evaluated by cell-based assays.RESULTS The hepatic steatosis,apoptosis,and fibrosis in the ALD mice model were significantly attenuated by EFN treatment.EFN promoted lipolysis and β-oxidation and enhanced autophagic and antioxidant capacities in EtOH-stimulated HepG2 cells,primarily through PPARαactivation.Moreover,EFN inhibited the Kupffer cell-mediated inflammatory response,with blunted hepatic exposure to lipopolysaccharide(LPS)and toll like receptor 4(TLR4)/nuclear factor kappa B(NF-κB)signaling.EFN improved intestinal hyperpermeability by restoring tight junction proteins and autophagy and by inhibiting apoptosis and proinflammatory responses.The protective effect on intestinal barrier function in the EtOH-stimulated Caco-2 cells was predominantly mediated by PPARδ activation.CONCLUSION EFN reduced ALD-related fibrosis by inhibiting lipid accumulation and apoptosis,enhancing hepatocyte autophagic and antioxidant capacities,and suppressing LPS/TLR4/NF-κB-mediated inflammatory responses by restoring intestinal barrier function.

The Effect of Immunotherapy on the Gut Microbiota,Intestinal Barrier,and Immune Function in Patients with Gastric Cancer

Objective:To explore the effect of immunotherapy on the gut microbiota,intestinal barrier,and immune function in patients with gastric cancer.Methods:From July 2023 to July 2024,60 patients with gastric cancer from our hospital were randomly divided into two groups,the control group and the study group,with 30 patients in each group.The control group received conventional treatment,while the study group received immunotherapy.A comparative analysis was conducted between the two groups on gut microbiota content(Bifidobacterium,Fusobacterium nucleatum,Streptococcus,Lactobacillus acidophilus),intestinal barrier indicators[D-lactate(D-LA),diamine oxidase(DAO),lipopolysaccharide(LPS)],immune function indicators[Immunoglobulin A(IgA),Immunoglobulin G(IgG),Immunoglobulin M(IgM)],adverse reactions,and treatment effects.Results:After treatment,the content of Bifidobacterium and Fusobacterium nucleatum in the study group was higher than in the control group,while the content of Streptococcus and Lactobacillus acidophilus was lower than in the control group(P<0.05).The levels of D-lactate and DAO in the study group were lower than in the control group,while the LPS level in the study group was higher(P<0.05).The levels of IgA and IgG in the study group were lower than in the control group,and the IgM level was also lower than in the control group(P<0.05).After treatment,the total incidence of adverse reactions in the study group was lower than in the control group(P<0.05).The overall treatment efficacy rate in the study group was higher than in the control group(P<0.05).Conclusion:Immunotherapy in patients with gastric cancer can improve gut microbiota,intestinal barrier,and immune function,reduce the occurrence of adverse reactions,and promote better clinical treatment outcomes,making it worthy of clinical recommendation.

Elafibranor alleviates alcohol-related liver fibrosis by restoring intestinal barrier function

We discuss the article by Koizumi et al published in the World Journal of Gastroenterology.Our focus is on the therapeutic targets for fibrosis associated with alcohol-related liver disease(ALD)and the mechanism of action of elafibranor(EFN),a dual agonist of peroxisome proliferator-activated receptorα(PPARα)and peroxisome PPARδ(PPARδ).EFN is currently in phase III clinical trials for the treatment of metabolic dysfunction-associated fatty liver disease and primary biliary cholangitis.ALD progresses from alcoholic fatty liver to alcoholic steatohepatitis(ASH),with chronic ASH eventually leading to fibrosis,cirrhosis,and,in some cases,hepatocellular carcinoma.The pathogenesis of ALD is driven by hepatic steatosis,oxidative stress,and acetaldehyde toxicity.Alcohol consumption disrupts lipid metabolism by inactivating PPARα,exacerbating the progression of ALD.EFN primarily activates PPARα,promoting lipolysis andβ-oxidation in ethanol-stimulated HepG2 cells,which significantly reduces hepatic steatosis,apoptosis,and fibrosis in an ALD mouse model.Additionally,alcohol disrupts the gut-liver axis at several interconnected levels,contributing to a proinflammatory environment in the liver.EFN helps alleviate intestinal hyperpermeability by restoring tight junction protein expression and autophagy,inhibiting apoptosis and inflammatory responses,and enhancing intestinal barrier function through PPARδactivation.

Influences of enteral nutrition combined with probiotics on gut microflora and barrier function of rats with abdominal infection

AIM： To investigate the influences of enteral, parenteral nutrition and probiotics delivered by gut on intestinal microecology, epithelial tight junctions, immune and barrier function of rats with abdominal infection. METHODS： Rat abdominal infection models established with cecal ligation and perforation method, were divided into three groups： parenteral nutrition （PN group, n = 7）, PN＋enteral nutrition （EN group, n = 7） and PN ＋ EN ＋ probiotics （probiotics group, n = 7） via the needle jejunostomy and neck vein for five days. The total nutritional supplement of the three groups was isonitrogenic and isocaloric. Probiotics was delivered by jejunostomy 10 mL/d （1 x 10^8 cfu/mL）. The rats were killed on the sixth day. The feces in the cecum were cultured for anaerobic bacterial growth and analyzed with bacterial group DNA fingerprint profile with random amplified polymorphic DNA. The transmembrane binding proteins （occludin） and IgA level in plasma cells of intestine epithelium in colon and terminal ileum were measured by an immunohistochemistry method. The ultrastructure of intestinal epithelial tight junctions in colon and small intestine was observed by electronmicroscopy. Vena cava blood and the homogenated tissue of liver, lung and mesenteric lymph nodes were cultured to determine the bacterial translocations, and endotoxin in the blood from portal vein was detected. RESULTS： （1） The amount of bacteria of gut species in EN group and probiotic group was higher than that in PN group. The DNA-proflles in EN group and probiotic group were similar to that of normal rats. The number of DNAprofiles in probiotics group was much more than that in PN group and EN group. Moreover, there were strange stripes in PN group. （2） The expression of occludin and IgA in the small and large intestine in EN group （2.309 ± 0.336, 15.440 ± 2.383） and probiotic group （2.938 ± 0.515, 16.230 ± 3.183） was improved as compared with PN group （1.207 ± 0.587, P 〈 0.05, 11.189 ± 2.108, P 〈 0.01）. The expression of occludin in probiotic group （intestine： 2.93 ± 0.515; cecum： 3.40 ± 0.617） was higher than that in EN group （intestine： 2.309 ± 0.336; cecum： 2.076 ± 0.670; P 〈 0.05）. The expression of IgA, especially in EN group （intestine： 15.440 ± 2.383） and probiotic EN group （large intestine： 12.516 ± 1.542） significantly increased as compared with PN group （intestine： 11.189 ± 2.108; cecum： 10.160 ± 1.643; P 〈 0.01）. The intestinal epithelial tight junctions and microvilli of the probiotic group were more intact than those in the PN group. （3） The bacterial translocations in blood, liver, lung and mesenteric lymph nodes, and the levels of endotoxin were significantly reduced in probiotic （0.082 ± 0.029） and EN （0.125 ± 0.040） groups as compared with PN group （0.403 ± 0.181, P 〈 0.05）. CONCLUSION： Application of EN combined with probiotics could improve the expression of transmembrane binding proteins （occludin） and IgA, correct the intestinal flora disturbance, maintain gut barrier functions and tight junctions, and reduce the occurrence of gut bacterial translocation.

Gegen Qinlian decoction enhances immunity and protects intestinal barrier function in colorectal cancer patients via gut microbiota

BACKGROUND We previously showed,using the Traditional Chinese Medicine System Pharmacology Database,that Gegen Qinlian decoction(GQD)had a direct antitumor effect,and was combined with programmed cell death protein(PD)-1 inhibitors to treat microsatellite stable(MSS)tumor-bearing mice.However,the effect of GQD on patients with colorectal cancer(CRC)is not clear.AIM To determine the therapeutic mechanism of GQD in improving immune function,reducing inflammation and protecting intestinal barrier function.METHODS Seventy patients with CRC were included in this study:37 in the control group and 33 in the treatment group.The proportions of CD4+T,CD8+T,natural killer(NK),NKT and T regulatory cells were measured by flow cytometry.Levels of the cytokines tumor necrosis factor(TNF)-α,interferon(IFN)-γ,interleukin(IL)-2,IL-6,IL-10 and serotonin(5-hydroxytryptamine;5-HT)in serum were assessed by enzyme-linked immunosorbent assay(ELISA).The expression of zonula occludens(ZO)-1,occludin,nuclear factor(NF)-κB and TNF-αin tumor and normal tissues was measured by immunohistochemistry.The composition of gut microbiota from patients in the treatment group was assessed using 16S rDNA analysis.RESULTS There were no adverse events in the treatment group.The proportion of CD4+T cells and NKT cells in the post-treatment group was significantly higher than that in the pre-treatment and control groups(P<0.05).The level of TNF-αin the posttreatment group was significantly lower than that in the pre-treatment and control groups(P<0.05).The concentration of 5-HT in the post-treatment group was significantly lower than that in the pre-treatment group(P<0.05).The expression of ZO-1 and occludin in tumor tissues in the treatment group was significantly higher than that in the control group(P<0.05).The expression of ZO-1 in normal tissues of the treatment group was significantly higher than that in the control group(P=0.010).Compared with the control group,expression of NF-κB and TNF-αin tumor tissues of the treatment group was significantly decreased(P<0.05).Compared with the pre-treatment group,GQD decreased the relative abundance of Megamonas and Veillonella.In addition,GQD increased the relative abundance of Bacteroides,Akkermansia and Prevotella.CONCLUSION GQD enhances immunity and protects intestinal barrier function in patients with CRC by regulating the composition of gut microbiota.

Effect of lactobacillus on the gut microflora and barrier function of the rats with abdominal infection

AIM:To investigate the effect of probiotics supplemented by gut on the tight junctions of epithelial cells, barrier function and the microflora of rats with abdominal infection. METHODS: After the model of cecal ligation and perforation established, SD rats were divided into two groups: parenteral nutrition (PN) group and PIM+probiotics (probiotics) group, PN solution was supplemented by neck vein and probiotics was delivered via the jejunostomy tube for five days. Vena cava blood and the homogenated tissue of liver, lung and mesenteric lymph nodes were cultured to determine the bacterial translocation rate (BTR). The ultra-structure of epithelial tight junctions and microvilli of the gut were observed by electron microscopy; occluding expression was measured by indirect-immune fluorescence method; anaerobic bacterial growth by anaerobic culture and DNA fingerprint of bacterial colonies of the feces by PCR. RESULTS: The quantity of lactobacteria and bifydobacteria in probiotics group was higher than that of PN group. The profiles of DNA fingerprint expression in probiotics group were similar to that in the normal group, a new 16S rDNA sequence appeared in the profile in PN group. The occludin expression, the integrality of the gut epithelial tight junction and microvilli in probiotics group were improved as compared with PN group. The BTR and endotoxin in blood were reduced more significantly in probiotics group as compared with PN group. CONCLUSION: The probiotics could improve the gut microflora disturbance, increase occludin expression, maintain the gut epithelial tight junction and decrease the bacterial translocations rate.

Tauroursodeoxycholic acid(TUDCA)improves intestinal barrier function associated with TGR5-MLCK pathway and the alteration of serum metabolites and gut bacteria in weaned piglets

Background:Tauroursodeoxycholic acid(TUDCA),a hydrophilic bile acid,is the main medicinal component of bear bile and is commonly used to treat a variety of hepatobiliary diseases.Meanwhile,TUDCA has been shown to modulate the intestinal barrier function and alleviate DSS-induced colitis in mice.However,the effect of TUDCA on the intestinal barrier of weaned piglets remains largely unclear.Methods:The weaned piglets and porcine IPEC-J2 intestinal epithelial cells were used to investigate the effects of TUDCA on intestinal barrier function in weaned piglets and explore the possible underlying mechanisms.In vivo,72 healthy weaned piglets were randomly allocated into 2 groups according to their gender and body weight,and piglets were fed the basal diet with 0(control,CON)and 200 mg/kg TUDCA for 30 d,respectively.Three female and three male piglets reflecting the average bodyweight were slaughtered in each group and samples were collected.In vitro,IPEC-J2 cells were subjected to 100μmol/L TUDCA to explore the possible underlying mechanisms.Results:Our results demonstrated that dietary TUDCA supplementation significantly reduced the diarrhea incidence of weaned piglets,possibly attributing to the TUDCA-enhanced intestinal barrier function and immunity.In addition,TUDCA supplementation altered serum metabolites and the relative abundance of certain gut bacteria,which might contribute to the improved intestinal barrier function.Furthermore,the in-vitro results showed that TUDCA improved the E.coli-induced epithelial barrier impairment of IPEC-J2 cells and increased Takeda G-coupled protein receptor 5(TGR5)protein expression.However,knockdown of TGR5 and inhibition of myosin light chain kinase(MLCK)pathway abolished the TUDCA-improved epithelial barrier impairment in E.coli-treated IPEC-J2 cells,indicating the involvement of TGR5-MLCK in this process.Conclusions:These findings showed that TUDCA improved intestinal barrier function associated with TGR5-MLCK pathway and the alteration of serum metabolites and gut bacteria in weaned piglets,suggesting the potential application of TUDCA in improving gut health in piglet production.

Synergistic effects of alginate oligosaccharide and cyanidin-3-O-glucoside on the amelioration of intestinal barrier function in mice

Emerging evidence shows that dietary oligosaccharides are important prebiotics that can improve intestinal flora,while dietary polyphenols can act directly on intestinal cells.However,information about their synergistic effects on gut health is still limited.In this study,alginate oligosaccharide(AOS)and cyanidin-3-O-glucoside(C3G)were selected as a common marine plant oligosaccharide and terrestrial plant polyphenol,respectively,to study their effects on intestinal health.The results show that,in comparison to their individual applications,the combination of AOS and C3G(mass ratio,3:1)displayed a stronger ability to up-regulate the expression of tight junction proteins,while enhanced intestinal epithelial barrier was also observed and levels of mucin-2 andβ-defensins were simultaneously increased in the intestinal mucus.Interestingly,the secretion of immunoglobulin A and immune-related cytokines were approximately doubled by the AOS+C3G mixture.In addition,the AOS+C3G mixture was found to be more conducive to the positive transformation of intestinal flora,which stimulated the growth of beneficial bacteria Akkermansia,Lachnospiraceae and Feacalibaculum while inhibiting the growth of harmful bacteria Helicobacter and Turicibacter.The data generated herein thus suggests that dietary oligosaccharides and dietary polyphenols may be more beneficial to intestinal health when applied in combination than their individual effects alone.

GUT BARRIER FUNCTION DAMAGE FOLLOWING MULTIPLE FIREARM INJURIES IN A PORCINE MODEL

Objective. To study the characteristics and pathogenesis of gut barrier damage following multiple firearm injuries in a porcine model. Methods. Twenty four small pigs were divided into 4 groups: control group (n=6, group C), group H (n=6, gunshot induced tangential fracture of parietal bone), group L (n=6, gunshot induced comminuted fracture of bilateral femora) and group M (n=6, combined group H+L). Gastric intramucosal pH (pHi), plasma endotoxin levels in portal vein, and plasma D lactate levels were measured and blood samples were cultured at different intervals after trauma. The animals were sacrificed at 72 h following trauma and intestinal tissues were harvested for pathological examination and diamine oxidase (DAO) activity measurement. Results. In group M at 72 h, pHi was significantly lower than that of group H and L (P< 0.01), and plasma endotoxin level was significantly higher than that of group H (P< 0.01) and group L (P< 0.05). Simultaneously, in groupM, D lactate level was markedly higher than that of group H (P< 0.01), and incidence of positive blood culture was much higher than that of group H and L (P<0.05). Necrosis and exfoliation were revealed at ileum villus top in all traumagroups, especially in group M, in which ileum DAO activity declined most significantly as well. Conclusion. Multiple trauma is prone to cause gastrointestinal ischemia even without hemorrhagic shock. The damage of gut barrier in multiple trauma appears to be more severe than that in one site trauma, thereby promoting gut derived endotoxemia and bacterial translocation and contributing to the development of endogenous infection.SURGICAL TREATMENT OF MALIGNANTESOPHAGEAL TUMORS IN PUMC HOSPITAL Guo Huiqin,Li Zejian ,Zhang Fan1 ,Zhang Zhiyong,Xu Letian ,Li Weidong2,Wang Xiuqin2and Wu Min2Department of Thoracic Surgery, PUMC Hospital, CAMS &PUMC, Beijing 100730Key words malignant esophageal tumors; early diagnosis; FHIT geneTo study how to prolong the postoperative survival time of the patientswith malignant esophageal tumors. The clinical data of 1098 patients with malignant esophageal tumors from 1961 to 1992 were retrospectively analyzed. The deletion of fragile histamine triplet (FHIT) gene (a tumor suppressor gene) in 30 fresh esophageal samples obtained in 1996 was detected with PCR and RT PCR method. The resectability was raised gradually and the operative morbidity and mortality decreased year by year, but there was no significant improvement on the postoperative 5 year survival rate. Delayed diagnosis and irradical resection influenced the long term survival. The deletion of cDNA of FHIT gene was 64.2%in esophageal cancer and 20%in the resected margin of the cancer. We believe that high grade atypical hyperplasia in esophageal epithelium and deletion of FHIT gene in esophageal cancer and its resected margin are pathological and molecular markers for early diagnosis of esophageal cancer respectively, and the latter may be one of the molecular markers for the resection. Early diagnosis and treatment, radical resection, and postoperative nutritional support are very important for the improvement of the postoperative survival time of the patients.

Junshanyinzhen tea extract prevents obesity by regulating gut microbiota and metabolic endotoxemia in high-fat diet fed rats

Obesity is associated with gut dysbiosis and metabolic endotoxin.Junshanyinzhen tea extract(JSTE)reduced fat accumulation and body weight in obese mice.However,the effects and mechanism of JSTE in preventing obesity were unclear.Therefore,we used different doses of JSTE(75,150 and 300 mg/(kg·day))to evaluate the effect on high-fat diet(HFD)-induced rats under 8 weeks of intervention.Here,our results showed that JSTE could significantly reduce body weight gain,blood lipid levels and fat accumulation,improve fatty damage in liver tissue(P<0.05).In addition,JSTE increased the expression of intestinal tight junction proteins(P<0.05),relieved metabolic endotoxemia(P<0.05)and chronic low-grade inflammation in HFD rats.Sequencing of fecal samples showed that JSTE could effectively reverse the microbial diversity and the ratio of Firmicutes to Bacteroidetes to normal levels in HFD-fed rats.Desulfovibrioceae and Erysipelotrichaceae,which are positively related to obesity,were decreased by JSTE intervention(P<0.05).while Bifidobacteriaceae,Bacteroidaceae,Akkermansia,and Clostridium,which are negatively related to obesity,were increased.Together,these results suggested that JSTE might effectively prevent obesity by modulating gut microbiota dysbiosis,intestinal barrier dysfunction,metabolic endotoxemia and chronic low-grade infl ammation in HFD-induced rats.

Gut microbiota remodeling drived by dietary millet protein prevents the metabolic syndrome

Metabolic syndrome(Met S)is a chronic disease associated with the disturbance of gut microbiota homeostasis.Metabolites derived from gut microbes play essential roles in Met S prevention and therapy.Here,we focused on the inhibitory effect of the extract of millet bran protein(EMBP)on a high-fat diet(HFD)-induced Met S,aiming to identify gut microbiota and their metabolites that involve in the anti-Met S activity of EMBP.The obesity,chronic inflammation,insulin resistance in Met S mouse models were abolished after EMBP treatment.The protective mechanism of EMBP against HFD-induced Met S may depend on improved gut barrier function.Using microbiome analysis,we found that EMBP supplementation improved gut microbiome dysbiosis in Met S mice,specifically upregulating Bacteroides acidifaciens.The fecal microbiota transplantation(FMT)also demonstrated this phenomenon.In addition,metabolomic analysis showed that EMBP mediates metabolic profiling reprogramming in Met S mice.Notably,a microbiota-derived metabolite,gamma-aminobutyric acid(GABA),is enriched by EMBP.In addition,exogenous GABA treatment produced a similar protective effect to EMBP by improving NRF2-dependent gut barrier function to protect HFDinduced Met S.The results suggest that EMBP suppress host Met S by remodeling of gut microbiota as an effective candidate for next-generation medicine food dual purpose dietary supplement to intervene in MetS.

Acupuncture ameliorates atopic dermatitis by modulating gut barrier function in a gut microbiota-dependent manner in mice

Objective Atopic dermatitis(AD)is a chronic inflammatory skin disease that may be linked to changes in the gut microbiome.Acupuncture has been proven to be effective in reducing AD symptoms without serious adverse events,but its underlying mechanism is not completely understood.The purpose of this study was to investigate whether the potential effect of acupuncture on AD is gut microbiota-dependent.Methods AD-like skin lesions were induced by applying MC903 topically to the cheek of the mouse.Acupuncture was done at the Gok-Ji(LI11)acupoints.AD-like symptoms were assessed by lesion scores,scratching behavior,and histopathological changes;intestinal barrier function was measured by fecal output,serum lipopolysaccharide levels,histopathological changes,and mRNA expression of markers involved in intestinal permeability and inflammation.Gut microbiota was profiled using 16S rRNA gene sequencing from fecal samples.Results Acupuncture effectively improved chronic itch as well as the AD-like skin lesions with epidermal thickening,and also significantly altered gut microbiota structure as revealed byβ-diversity indices and analysis of similarities.These beneficial effects were eliminated by antibiotic depletion of gut microbiota,but were reproduced in gut microbiota-depleted mice that received a fecal microbiota transplant from acupuncture-treated mice.Interestingly,AD mice had intestinal barrier dysfunction as indicated by increased intestinal permeability,atrophy of the mucosal structure(reduced villus height and crypt depth),decreased expression of tight junctions and mucus synthesis genes,and increased expression of inflammatory mediators in the ileum.Acupuncture attenuated these abnormalities,which was gut microbiota-dependent.Conclusion Acupuncture ameliorates AD-like phenotypes in a gut microbiota-dependent manner and some of these positive benefits are explained by modulation of the intestinal barrier,providing new perspective for non-pharmacological strategies for modulating gut microbiota to prevent and treat AD.

Clinical Studies Evaluating Effects of Probiotics on Parameters of Intestinal Barrier Function

The intestinal barrier is important in preventing translocation of bacteria, toxins and antigens from the lumen of the gut into the body. Enhanced permeability, or gut leakiness, has been associated with different diseases. Probiotics can, strain-specifically, improve the epithelial barrier function. However, so far most researches have used cell lines or animal models due to the difficulty of measuring the effects of products on the epithelial barrier function in vivo in humans. Here a systematic literature search was performed to find articles addressing the effects of probiotics on the barrier function in human trials. The Pubmed database was searched (January 2013) to identify human in vivo studies with probiotic products in which parameters for epithelial barrier function were measured. In total 29 studies were identified, but patients, bacterial characteristics and methods to measure intestinal barrier function caused large heterogeneity among these studies. About half of the studies showed positive results of probiotics on the epithelial barrier function, indicating a clear potential of probiotics in this field. In a case series of 14 patients using Ecologica825, a probiotic food supplement with known effect on epithelial barrier function, different markers of intestinal integrity improved significantly. Further studies in this field should consider strain(s), dose and duration of the probiotic supplementation as well as the markers used to measure epithelial barrier function. Besides the lactulose/mannitol test, zonulin and α1-antitrypsin might be valuable markers to measure epithelial barrier function in future experiments.

Intestinal mucosal barrier in functional constipation:Dose it change?

BACKGROUND The intestinal mucosal barrier is the first line of defense against numerous harmful substances,and it contributes to the maintenance of intestinal homeostasis.Recent studies reported that structural and functional changes in the intestinal mucosal barrier were involved in the pathogenesis of several intestinal diseases.However,no study thoroughly evaluated this barrier in patients with functional constipation(FC).AIM To investigate the intestinal mucosal barrier in FC,including the mucus barrier,intercellular junctions,mucosal immunity and gut permeability.METHODS Forty FC patients who fulfilled the Rome IV criteria and 24 healthy controls were recruited in the Department of Gastroenterology of China-Japan Friendship Hospital.The colonic mucus barrier,intercellular junctions in the colonic epithelium,mucosal immune state and gut permeability in FC patients were comprehensively examined.Goblet cells were stained with Alcian Blue/Periodic acid Schiff(AB/PAS)and counted.The ultrastructure of intercellular junctional complexes was observed under an electron microscope.Occludin and zonula occludens-1(ZO-1)in the colonic mucosa were located and quantified using immunohistochemistry and quantitative real-time polymerase chain reaction.Colonic CD3+intraepithelial lymphocytes(IELs)and CD3+lymphocytes in the lamina propria were identified and counted using immunofluorescence.The serum levels of D-lactic acid and zonulin were detected using enzyme-linked immunosorbent assay.RESULTS Compared to healthy controls,the staining of mucus secreted by goblet cells was darker in FC patients,and the number of goblet cells per upper crypt in the colonic mucosa was significantly increased in FC patients(control,18.67±2.99;FC,22.42±4.09;P=0.001).The intercellular junctional complexes in the colonic epithelium were integral in FC patients.The distribution of mucosal occludin and ZO-1 was not altered in FC patients.No significant differences were found in occludin(control,5.76E-2±1.62E-2;FC,5.17E-2±1.80E-2;P=0.240)and ZO-1(control,2.29E-2±0.93E-2;FC,2.68E-2±1.60E-2;P=0.333)protein expression between the two groups.The mRNA levels in occludin and ZO-1 were not modified in FC patients compared to healthy controls(P=0.145,P=0.451,respectively).No significant differences were observed in the number of CD3+IELs per 100 epithelial cells(control,5.62±2.06;FC,4.50±2.16;P=0.070)and CD3+lamina propria lymphocytes(control,19.69±6.04/mm^(2);FC,22.70±11.38/mm^(2);P=0.273).There were no significant differences in serum D-lactic acid[control,5.21(4.46,5.49)mmol/L;FC,4.63(4.31,5.42)mmol/L;P=0.112]or zonulin[control,1.36(0.53,2.15)ng/mL;FC,0.94(0.47,1.56)ng/mL;P=0.185]levels between FC patients and healthy controls.CONCLUSION The intestinal mucosal barrier in FC patients exhibits a compensatory increase in goblet cells and integral intercellular junctions without activation of mucosal immunity or increased gut permeability.

片仔癀通过调节小鼠的肠道菌群和代谢物抑制非酒精性脂肪性肝炎

Non-alcoholic steatohepatitis(NASH)is a severe form of non-alcoholic fatty liver disease without effective treatment.The traditional Chinese medicine formulation Pien Tze Huang(PTH)can suppress inflammatory diseases.Here,we evaluate the effects of PTH on the evolution of NASH and its underlying mechanisms.We found that PTH prevented the development of steatohepatitis induced by various dietary models,including a high-fat high-cholesterol(HFHC)diet,choline-deficient high-fat diet(CD-HFD),and methionine-and choline-deficient(MCD)diet,along with significant suppression of liver injury,hepatic triglyceride,and lipid peroxidation.Moreover,ten days of PTH treatment after the onset of NASH significantly ameliorated MCD diet-induced steatosis and liver injury in mice.Through the metagenomic sequencing of stool samples,we found that PTH administration restored the gut microbiota with enrichment of probiotics including Lactobacillus acidophilus(L.acidophilus),Lactobacillus plantarum,Lactococcus lactis,and Bacillus subtilis.The enriched L.acidophilus prevented MCD diet-induced steatohepatitis.In addition,PTH restored the gut barrier function in mice with steatohepatitis,as evidenced by reduced intestinal permeability,decreased serum lipopolysaccharides(LPS)level,and increased epithelial tightjunction protein E-cadherin expression.Our metabolomic analysis via liquid chromatography-mass spectrometry profiling identified the alteration in the metabolism of bile acids in the portal vein of PTHtreated mice.We further confirmed that an intact gut microbiota is necessary for PTH to exhibit antisteatohepatitis effects.In conclusion,PTH protects against steatohepatitis development by modulating the gut microbiota and metabolites.PTH is a potential promising prophylactic and therapeutic option for patients with NASH.

Elafibranor:A promising treatment for alcohol-associated liver disease?

We comment on an article by Koizumi et al.Elafibranor(EFN)is a dual pero-xisome proliferator-activated receptorα/δagonist.The experimental results from Koizumi et al demonstrated that EFN significantly increases intestinal barrier function and ameliorates liver fibrosis.These positive outcomes suggest that EFN could be a promising therapeutic option for alcohol-associated liver disease(ALD).However,this study has limitations that necessitate further research to evaluate the efficacy of EFN.Future studies should consider the use of more appropriate animal models and cell types,optimize the administration routes and dosages of the drug,and conduct an in-depth investigation into the underlying mechanisms of action to determine the therapeutic effects of EFN in humans.With sustained and in-depth research,EFN has the potential to emerge as a novel therapeutic agent for the treatment of ALD.

Critical analysis of the effects of proton pump inhibitors on inflammatory bowel disease:An updated review

This letter critically evaluates the effects of proton pump inhibitors(PPIs)on inflammatory bowel disease,particularly focusing on Crohn's disease(CD)and ulcerative colitis(UC),as discussed in Liang et al’s recent review.While the review provides significant insights,it relies heavily on cross-sectional and observational studies,which limits the ability to draw causal inferences.The heterogeneous study populations and inconsistent definitions of long-term PPI use further complicate the findings.This letter also highlights the need for rigorous control of confounding factors and considers the potential publication bias in the existing literature.The implications of these issues are discussed in the context of both CD and UC,and future research directions are proposed to address these shortcomings.

Probiotics and gut health:A special focus on liver diseases

Probiotic bacteria have well-established beneficial ef-fects in the management of diarrhoeal diseases.Newer evidence suggests that probiotics have the potential to reduce the risk of developing inflammatory bowel diseases and intestinal bacterial overgrowth after gut surgery.In liver health,the main benefits of probiotics might occur through preventing the production and/or uptake of lipopolysaccharides in the gut,and therefore reducing levels of low-grade inflammation.Specific immune stimulation by probiotics through processes involving dendritic cells might also be beneficial to the host immunological status and help prevent pathogen translocation.Hepatic fat metabolism also seems to be influenced by the presence of commensal bacteria,and potentially by probiotics;although the mechanisms by which probiotic might act on the liver are still unclear.However,this might be of major importance in the fu-ture because low-grade inflammation,hepatic fat infil-tration,and hepatitis might become more prevalent as a result of high fat intake and the increased prevalence of obesity.

补肾化痰方通过调控肠道菌及PPARγ通路治疗多囊卵巢综合征的机制

目的:探究补肾化痰方对多囊卵巢综合征(PCOS)模型小鼠肠道菌群多样性的调节作用及其治疗PCOS的相关机制。方法:24只无特定病原体级成年雌性C57BL/6J小鼠随机分为三组:空白对照组、模型对照组(使用来曲唑联合高脂饲料诱导)、中药治疗组(造模结束后连续灌服补肾化痰方混悬液35 d)。采用酶联免疫吸附测定法检测小鼠性激素水平;苏木精-伊红染色后光镜下观察卵巢形态;收集各组小鼠结肠内粪便,采用16S rRNA测序进行肠道菌群检测;气相色谱-质谱法检测短链脂肪酸含量;免疫组织化学法检测结肠过氧化物酶体增殖物激活受体(PPARγ)表达;实时逆转录聚合酶链反应法检测肠道上皮黏蛋白2、闭合蛋白1和紧密连接蛋白1(ZO-1)、PPARγ的mRNA表达;蛋白质印迹法检测诱导型一氧化氮合酶(iNOS)、PPARγ蛋白表达。结果:与空白对照组比较,模型对照组体重、血清卵泡刺激素、黄体生成素和睾酮水平均升高,血清雌二醇水平降低(均P<0.01),光镜下卵巢结构符合PCOS病理特征;中药治疗组血清性激素水平和卵巢结构较模型对照组改善。模型对照组肠道菌群多样性较空白对照组发生变化。与空白对照组比较,在门水平,模型对照组厚壁菌丰度下降,疣微菌、变形菌、放线菌丰度升高(均P<0.05);在属水平,模型对照组乳酸菌丰度显著下降,阿克曼菌、乳梭菌、乳球菌、产粪甾醇真细菌丰度升高(均P<0.05)。补肾化痰方治疗后小鼠肠道菌群紊乱状态得到一定程度的改善。与空白对照组比较,模型对照组粪便中乙酸、丙酸、丁酸含量均下降(均P<0.05),而中药治疗组乙酸、丙酸、丁酸含量较模型对照组均增加,其中丙酸和丁酸含量与模型对照组差异有统计学意义(均P<0.05)。与空白对照组比较,模型对照组肠道PPARγ表达降低,ZO-1 mRNA表达增加,黏蛋白2、闭合蛋白1 mRNA表达减少,iNOS蛋白表达增加(均P<0.05);与模型对照组比较,中药治疗组PPARγ蛋白表达增加,闭合蛋白1、黏蛋白2 mRNA表达显著增加(均P<0.05),ZO-1 mRNA表达减少,iNOS蛋白表达减少。结论:来曲唑联合高脂饲料诱导的PCOS小鼠存在菌群失调状态,补肾化痰方通过调节肠道菌群种属分布可能有助于提高短链脂肪酸水平从而激活肠PPARγ通路,改善肠屏障功能,达到治疗PCOS的目的。

植物精油对鸡抵御沙门氏菌感染作用的研究进展

沙门氏菌病严重危害家禽养殖业,造成重大经济损失,并引发公共卫生安全问题。植物精油能够显著抑制病原菌生长繁殖,并通过改善机体抗氧化能力、免疫性能以及肠道黏膜屏障功能等方式,发挥抵御鸡沙门氏菌感染的作用。本文综述了植物精油的抗菌活性、抗菌机制及其对鸡抵御沙门氏菌感染的作用,以期为植物精油应用于防治鸡沙门氏菌病提供参考。