Lifestyle and genetic predisposition are associated with incident irritable bowel syndrome: A population-based prospective cohort study.

Few prospective studies have investigated the joint effect of lifestyle factors and genetic susceptibility on the risk of irritable bowel syndrome (IBS). This study aims to evaluate the associations of lifestyle and genetic factors with incident IBS in the UK Biobank. We analyzed data from 481,057 participants (54% female) without prevalent IBS at enrollment in the UK Biobank. An overall healthy lifestyle was defined using six modifiable lifestyle factors, including smoking, body mass index (BMI), sleep duration, diet, physical activity, and alcohol consumption, and hence categorized into 'favorable', 'intermediate', and 'unfavorable' lifestyles. A Cox proportional hazard model was used to investigate the association between a healthy lifestyle and incident IBS. Furthermore, we constructed a polygenic risk score (PRS) for IBS and assessed whether lifestyle modified the effect of genetics on the development of IBS. During a median follow-up of 12.1 years, 8645 incident IBS were ascertained. Specifically, among the six modifiable lifestyle factors, adequate sleep demonstrates the greatest protective effect (hazard ratio [HR]: 0.72, 95% CI: 0.69,0.75) against IBS. Compared with a favorable lifestyle, an unfavorable lifestyle was associated with a 56% (95% CI: 46%-67%) increased risk of IBS (P = 8.99 × 10-40). The risk of incident IBS was 12% (95% CI: 4%-21%) higher among those at high genetic risk compared with those at low genetic risk (P = 0.005). When considering the joint effect of lifestyle and genetic susceptibility, the HR nearly doubled among individuals with high genetic risk and unfavorable lifestyle (HR: 1.80; 95% CI:1.51-2.15; P = 3.50 × 10-11) compared to those with low genetic risk and favorable lifestyle. No multiplicative or addictive interaction was observed between lifestyle and genetics. The findings from this study indicated that lifestyle and genetic factors were independently associated with the risk of incident IBS. All these results implicated a possible clinical strategy of lowering the incidence of IBS by advocating a healthy lifestyle.

Rome III Criteria Capture Higher Irritable Bowel Syndrome SNP-Heritability and Highlight a Novel Genetic Link With Cardiovascular Traits.

BACKGROUND & AIMS: Irritable bowel syndrome (IBS) shows genetic predisposition, and large-scale genome-wide association studies (GWAS) are emerging, based on heterogeneous disease definitions. We investigated the genetic architecture of IBS defined according to gold standard Rome Criteria. METHODS: We conducted GWAS meta-analyses of Rome III IBS and its subtypes in 24,735 IBS cases and 77,149 asymptomatic control subjects from 2 independent European cohorts (UK Biobank and Lifelines). Single-nucleotide polymorphism (SNP)-based heritability (h2SNP) and genetic correlations (rg) with other traits were calculated. IBS risk loci were functionally annotated to identify candidate genes. Sensitivity and conditional analyses were conducted to assess impact of confounders. Polygenic risk scores were computed and tested in independent datasets. RESULTS: Rome III IBS showed significant SNP-heritability (up to 13%) and similar genetic architecture across subtypes, including those with manifestations at the opposite ends of the symptom spectrum (rg = 0.48 between IBS-D and IBS-C). Genetic correlations with other traits highlighted commonalities with family history of heart disease and hypertension, coronary artery disease, and angina pectoris (rg = 0.20-0.45), among others. Four independent GWAS signals (P < 5×10-8) were detected, including 2 novel loci for IBS (rs2035380) and IBS-mixed (rs2048419) that had been previously associated with hypertension and coronary artery disease. Functional annotation of GWAS risk loci revealed genes implicated in circadian rhythm (BMAL1), intestinal barrier (CLDN23), immunomodulation (MFHAS1), and the cyclic adenosine monophosphate pathway (ADCY2). Polygenic risk scores allowed the identification of individuals at increased risk of IBS (odds ratio, 1.34; P = 1.1×10-3). CONCLUSIONS: Rome III Criteria capture higher SNP-heritability than previously estimated for IBS. The identified link between IBS and cardiovascular traits may contribute to the delineation of alternative therapeutic strategies, warranting further investigation.

The Role of Inflammatory Biomarkers in Mediating the Effect of Inflammatory Bowel Disease on nonmalignant Digestive System Diseases: A Multivariable Mendelian Randomized Study.

Background: While observation studies have shown a positive correlation between inflammatory bowel disease (IBD) and the risk of nonmalignant digestive system diseases, a definitive causal relationship has not yet been clearly established. Methods: Mendelian randomization (MR) was employed to investigate the potential causal association between genetic susceptibility to IBD and nonmalignant gastrointestinal diseases. Genetic variants were extracted as instrumental variables (IVs) from a genome-wide association study (GWAS) meta-analysis, which included 12,194 cases of Crohn's disease (CD) and 28,072 control cases of European ancestry. The GWAS for ulcerative colitis (UC) included 12,366 UC and 33,609 control cases of European ancestry. All IVs reached genome-wide significance (GWAS p value <5 × 10-8). Summary-level data for acute pancreatitis (AP), irritable bowel syndrome (IBS), gastroesophageal reflux disease, cholelithiasis, and CeD (celiac disease) were obtained from the GWAS meta-analysis and the FinnGen dataset. Summary-level data on relevant inflammatory factors were provided by the International Genetic Consortium. Univariate MR analysis was conducted using inverse variance weighting as the primary method for estimating causal effects. Multivariate MR analyses were also performed to detect possible mediators. Results: Genetic susceptibility to UC was associated with an increased risk of AP (OR = 1.08; 95% CI = 1.03-1.13; p=0.002) and IBS odds ratio (OR] = 1.07; 95% confidence interval (CI] = 1.03-1.11; (p < 0.001). In terms of potential mediators, interleukin 6 (IL-6) had a driving effect on the association between UC and AP. There was no apparent evidence of increased risk with CD. Meanwhile, genetic susceptibility to CD increases the risk of CeD (OR = 1.14; 95% CI = 1.03-1.25; p=0.01). Conclusions: The evidence suggests that UC is associated with an elevated risk of AP and IBS, and IL-6 may be responsible in AP. CD is associated with an increased risk of developing CeD. Implementing a proactive monitoring program for assessing the risk of gastrointestinal diseases in UC patients, particularly those with elevated IL-6 levels, may be of interest. In addition, the presence of AP and IBS may indicate the presence of UC. Preventing CeD is an essential consideration in the therapeutic management of patients with CD.

Effect of moxibustion on colonic low-grade inflammatory response in rats with diarrhea-predominant irritable bowel syndrome based on mast cell degranulation. / åŸºäºŽè‚¥å¤§ç»†èƒžè„±é¢—ç²’æŽ¢è®¨è‰¾ç¸å¯¹è ¹æ³»åž‹è‚ æ˜“æ¿€ç»¼åˆå¾å¤§é¼ ç»“è‚ ä½Žåº¦ç‚Žæ€§ååº”çš„å½±å“.

OBJECTIVES: To observe the effects of moxibustion on colonic mast cell degranulation and inflammatory factor expression in rats with diarrhea-predominant irritable bowel syndrome (IBS-D), and explore the potential mechanism of moxibustion in treating IBS-D. METHODS: Forty-five rat pups born from 5 healthy SPF-grade pregnant SD rats, with 8 rats were randomly selected as the normal group. The remaining 37 rats were intervened with maternal separation, acetic acid enema, and chronic restraint stress to establish the IBS-D model. The successfully modeled 32 rats were then randomly assigned to a model group, a ketotifen group, a moxibustion group, and a moxibustion-medication group, with 8 rats in each group. The rats in the ketotifen group were intervened with intragastric administration of ketotifen solution (10 mL/kg); the rats in the moxibustion group were intervened with suspended moxibustion on bilateral "Tianshu" (ST 25) and "Shangjuxu" (ST 37); the rats in the moxibustion-medication group were intervened with suspended moxibustion combined with intragastric administration of ketotifen solution. All interventions were administered once daily for 7 consecutive days. The diarrhea rate and minimum volume threshold of abdominal withdrawal reflex (AWR) were calculated before and after modeling, as well as after intervention. After intervention, colonic tissue morphology was observed using HE staining; colonic mucosal ultrastructure was examined by scanning electron microscopy; colonic mast cell ultrastructure was observed using transmission electron microscopy; mast cell degranulation was assessed by toluidine blue staining; serum and colonic levels of histamine, interleukin (IL)-1ß, IL-6, IL-1α, trypsin-like enzyme, and protease-activated receptor 2 (PAR-2) were measured by ELISA; the Western blot and real-time quantitative PCR were employed to evaluate the protein and mRNA expression of colonic IL-1ß, IL-6, IL-1α, trypsin-like enzyme, and PAR-2; the immunofluorescence was used to detect the positive expression of histamine, IL-1ß, IL-6, IL-1α, trypsin-like enzyme, and PAR-2 in the colonic tissue. RESULTS: Compared to the normal group, the rats in the model group exhibited extensive infiltration of inflammatory cells in colonic tissue, severe damage to the colonic mucosa, disordered arrangement of villi, reduced electron density, and a significant decrease in granule quantity within mast cells. The diarrhea rate and mast cell degranulation rate were increased (P<0.01), AWR minimum volume threshold was decreased (P<0.01); the serum and colonic levels of histamine, IL-1ß, IL-6, IL-1α, trypsin-like enzyme, and PAR-2 were elevated (P<0.01); the positive expression of histamine, as well as protein, mRNA and positive expression of IL-1ß, IL-6, IL-1α, trypsin-like enzyme, and PAR-2 in the colon were all elevated (P<0.01). Compared to the model group, the rats in the ketotifen group, the moxibustion group, and the moxibustion-medication group exhibited significantly reduced infiltration of inflammatory cells in colonic tissue, relatively intact colonic mucosa, orderly arranged villi, increased electron density, and an augmented number of mast cell granules; the diarrhea rate and mast cell degranulation rate were decreased (P<0.01), and AWR minimum volume threshold was increased (P<0.01); the serum and colonic levels of histamine, IL-1ß, IL-6, IL-1α, trypsin-like enzyme, and PAR-2 were reduced (P<0.01); the positive expression of histamine, as well as protein, mRNA and positive expression of IL-1ß, IL-6, IL-1α, trypsin-like enzyme, and PAR-2 in the colon were all decreased (P<0.01). Compared to the ketotifen group, the moxibustion group showed decreased serum levels of histamine, IL-6, and trypsin-like enzyme (P<0.01, P<0.05), as well as reduced colonic levels of IL-1ß and IL-6 (P<0.01, P<0.05); the protein expression of colonic IL-1ß, IL-1α, and PAR-2 was reduced (P<0.05), and the positive expression of colonic IL-1ß and trypsin-like enzyme was reduced (P<0.01, P<0.05). Compared to both the ketotifen group and the moxibustion group, the moxibustion-medication group exhibited decreased diarrhea rate and mast cell degranulation rate (P<0.01), an increased AWR minimum volume threshold (P<0.01), reduced serum and colonic levels of histamine, IL-1ß, IL-6, IL-1α, trypsin-like enzyme, and PAR-2 (P<0.01), decreased protein expression of colonic IL-1ß, trypsin-like enzyme, and PAR-2 (P<0.01, P<0.05), reduced mRNA and positive expression of colonic IL-1ß, IL-6, IL-1α, trypsin-like enzyme, and PAR-2 (P<0.01, P<0.05), and decreased positive expression of colonic histamine (P<0.01). CONCLUSIONS: Moxibustion on "Tianshu" (ST 25) and "Shangjuxu" (ST 37) might inhibit low-grade inflammatory reactions in the colon of IBS-D model rats. The mechanism may be related to the inhibition of histamine and trypsin-like enzyme secreted by mast cell, thereby reducing the expression of related inflammatory factors.

Effect of acupuncture on the expression of neuropeptides and related inflammatory factors in rats with diarrhea-predominant irritable bowel syndrome. / é’ˆåˆºå¯¹è ¹æ³»åž‹è‚ æ˜“æ¿€ç»¼åˆå¾å¤§é¼ è„‘è‚ è‚½åŠç›¸å ³ç‚Žæ€§å› å­è¡¨è¾¾çš„å½±å“.

OBJECTIVES: To observe the effect of acupuncture on the expressions of neuropeptides and related inflammatory factors in rats with diarrhea-predominant irritable bowel syndrome(IBS-D), so as to explore the mechanism of acupuncture in the treatment of IBS-D. METHODS: Male Wistar rats were randomly divided into blank group, model group, medication group, and acupuncture group, with 6 rats in each group. Except for the blank group, the other groups were subjected to 14-day "acetic acid enema + restraint stress" to establish the IBS-D rat model. After successful modeling, the medication group received gavage of pinaverium bromide(15 mg/kg) once a day, and the acupuncture group received acupuncture at "Baihui"(GV20) and bilateral "Tianshu"(ST25), "Shangjuxu"(ST37), "Zusanli"(ST36), and "Taichong"(LR3) for 20 min every day, both groups were treated continuously for 14 days. The general state of the rats in each group was observed, and the body weight of the rats was measured. The open-field experiment was conducted to measure the horizontal and vertical movements, and the number of fecal pellets of rats. The histopathological morphology of hypothalamus and colon of rats was observed by HE staining. Toluidine blue staining was used to observe and count the mast cells(MCs) in the colon tissue of rats. ELISA was used to detect the serum contents of tumor necrosis factor-α(TNF-α) and interleukin(IL)-10. Real-time fluorescence quantitative PCR was performed to detect the mRNA expressions of calcitonin gene-related peptide(CGRP) in the hypothalamus and colon tissue. Western blot was used to detect the expressions of corticotropin-releasing factor(CRF) in the hypothalamus and colon tissue. RESULTS: HE staining showed that there was inflammatory cell infiltration in the lamina propria of colon in the model group, and it was reduced in the other groups. Compared with the blank group, the model group showed significantly decreased body weight, decreased walking distance and upright times in open field experiment, decreased serum IL-10 contents(P<0.05, P<0.01), increased fecal pellet number (P<0.01), increased MC number in the colon tissue, serum TNF-α contents, and CGRP mRNA expressions and CRF expressions in the hypothalamus and colon tissue(P<0.01). Compared with the model group, both medication and acupuncture groups showed significantly increased body weight, walking distance and upright times in the open-field experiment, and serum IL-10 contents(P<0.01, P<0.05), significantly decreased fecal pellet number (P<0.05), significantly decreased MC number in the colon tissue, serum TNF-α contents, and CGRP mRNA expressions in the hypothalamus and colon tissue(P<0.01)；at the same time, the acupuncture group showed significantly decreased CRF expressions in the hypothalamus and colon tissue(P<0.01, P<0.05). There was no significant difference in the above indicators between the medication group and the acupuncture group. CONCLUSIONS: Acupuncture can improve the general and emotional state, inflammatory response, and neuropeptide expression in rats with IBS-D, and alleviate the symptoms of IBS-D, which may be related to the regulation of neuropeptides and inflammatory factors levels.

DNA Methylation Signatures of Functional Somatic Syndromes: Systematic Review.

OBJECTIVE: Functional somatic syndromes (FSS) are highly prevalent across all levels of health care. The fact that they are characterized by medically unexplained symptoms, such as fatigue and pain, raises the important question of their underlying pathophysiology. Psychosocial stress represents a significant factor in the development of FSS and can induce long-term modifications at the epigenetic level. The aim of this review was to systematically review, for the first time, whether individuals with FSS are characterized by specific alterations in DNA methylation. METHODS: MEDLINE and PsycINFO were searched from the first available date to September 2022. The inclusion criteria were as follows: a) adults fulfilling the research diagnostic criteria for chronic fatigue syndrome, fibromyalgia syndrome, and/or irritable bowel syndrome; b) healthy control group; and c) candidate-gene or genome-wide study of DNA methylation. RESULTS: Sixteen studies ( N = 957) were included. In candidate-gene studies, specific sites within NR3C1 were identified, which were hypomethylated in individuals with chronic fatigue syndrome compared with healthy controls. In genome-wide studies in chronic fatigue syndrome, a hypomethylated site located to LY86 and hypermethylated sites within HLA-DQB1 were found. In genome-wide studies in fibromyalgia syndrome, differential methylation in sites related to HDAC4 , TMEM44 , KCNQ1 , SLC17A9 , PRKG1 , ALPK3 , TFAP2A , and LY6G5C was found. CONCLUSIONS: Individuals with chronic fatigue syndrome and fibromyalgia syndrome seem to be characterized by altered DNA methylation of genes regulating cellular signaling and immune functioning. In chronic fatigue syndrome, there is preliminary evidence for these to be implicated in key pathophysiological alterations, such as hypocortisolism and low-grade inflammation, and to contribute to the debilitating symptoms these individuals experience. PREREGISTRATION: PROSPERO identifier: CRD42022364720.

The multi-generational familial aggregation of interstitial cystitis, other chronic nociplastic pain disorders, depression, and panic disorder.

BACKGROUND: Interstitial cystitis/painful bladder syndrome (IC) is a chronic pelvic pain condition which has high comorbidity with other nociplastic, or unexplained, pain disorders [e.g. fibromyalgia (FM), irritable bowel syndrome (IBS), and myalgic encephalomyelitis/chronic fatigue (ME/CFS)] and some psychiatric conditions [major depressive disorder (MDD) and panic disorder (PD)]. Here we investigated the shared familiality of IC and these other nociplastic and psychiatric conditions. METHODS: Subjects were identified in the Utah Population Database, which links genealogy data back to the 1800s to medical record diagnosis billing code data back to 1995. We computed the relative risk of each of these disorders among first (FDR), second (SDR), and third-degree relatives (TDR) of six proband groups: IC, FM, IBS, ME/CFS, PD, and MDD. Given the known familial aggregation of each of these disorders, we conducted our analyses to test for heritable interrelationships using proband subgroups whose members did not have the diagnosis assessed in their relatives. RESULTS: We observed strong evidence for heritable interrelationships among all six disorders. Most analyses indicated significantly increased risk for each of the six disorders in FDR, SDR, and TDR of all or most proband groups. Out of 30 possible bidirectional disorder interrelationships, 26 were significant among FDR, 23 were significant among SDR, and 7 were significant among TDR. Clustering was observed in both close and distant relatives. CONCLUSIONS: Our results support a common, heritable component to IC and other nociplastic and psychiatric conditions.

Evaluation of the Impact of Some Single-Nucleotide Gene Polymorphisms on the Development of Adenomatous Polyps of the Colon in Patients with Irritable Bowel Syndrome.

BACKGROUND: The number of cases of irritable bowel syndrome is growing worldwide, in which adenomatous polyps can develop as a result of microinflammation of the colonic epithelium. Our study was aimed at the identification of the possible effect of single-nucleotide polymorphisms on the risk of the development of irritable bowel syndrome-related colonic adenomatous polyps. MATERIALS AND METHODS: The study involved 187 irritable bowel syndrome patients. The single-nucleotide polymorphisms were investigated by the polymerase chain reaction method and DNA was extracted with the phenol-chloroform: interleukin-1ß gene-31C/T (rs1143627), -511C/T (rs16944); interleukin-6 gene-174G/C (rs1800795); interleukin-10 gene-592C/A (rs1800872), -819T/C (rs1800871), -1082A/G (rs1800896); Toll-like receptor-2 gene Arg753Gln (rs5743708); Toll-like receptor-4 gene Thr399ile (rs4986791), Asp299Gly (rs4986790); and metalloproteinase-9 gene-8202A/G (rs11697325). The study of polymorphic loci was checked for compliance with the Hardy- Weinberg equilibrium using Fisher's exact test along with the analyses of the frequency of alleles and the genotypes. RESULTS: The association of diseases with G allele Toll-like receptor-2 gene Arg753Gln (rs5743708) was revealed in irritable bowel syndrome patients with adenomatous polyps of the colon (P < .0006) and AG single-nucleotide polymorphisms s of Toll-like receptor-2 gene (χ2 = 12.78, P < .002); A allele had a protective effect. The AG genotype metalloproteinase-9 gene-8202A/G (rs11697325) polymorphism in irritable bowel syndrome patients with adenomatous polyps of the colon had a protective effect (P < .05). AA genotype interleukin-10 gene-1082A/G (rs1800896) polymorphism in the irritable bowel syndrome patient (χ2 = 33.97, 4.0E-8) can be considered as the risk for adenomatous polyps of the colon in irritable bowel syndrome. CONCLUSION: G allele Toll-like receptor-2 gene Arg753Gln (rs5743708) and AA genotype interleukin-10 gene-1082A/G (rs1800896) polymorphisms can be the marker of the emergence of adenomatous polyps of the colon concomitant with irritable bowel syndrome.

Electroacupuncture alleviates water avoidance stress-induced irritable bowel syndrome in mice by improving intestinal barrier functions and suppressing the expression of inflammatory cytokines.

OBJECTIVE: To evaluate the effects and related mechanisms of electroacupuncture (EA) on irritable bowel syndrome (IBS). METHODS: Male C57BL/6 mice were randomly allocated into normal, model, and EA groups. Experimental IBS mice models were established by exposure to water avoidance stress (WAS). Mice in the EA group were treated with EA at bilateral Tianshu (ST 25) and Zusanli (ST 36) for 7 consecutive days, 15 min each day. Abdominal withdrawal reflex (AWR) tests and intestinal motility tests were performed to evaluate visceral sensitivity and intestinal motility of mice. Expression levels of tight junction proteins (TJPs) and inflammatory cytokines in colon tissues were determined through immunofluorescence, real-time polymerase chain reactions (PCR) and Western blot assays. RESULTS: EA alleviated visceral hypersensitivity and intestinal hypermotility in WAS-induced IBS mice. Moreover, EA promoted the expression of zonula occludens (ZO)-1, claudin-1, and occludin while suppressing the expression of interleukin (IL)-8, interferon (IFN)-γ, and tumor necrosis factor (TNF)-αin water avoidance stress (WAS)-induced irritable bowel syndrome (IBS) mice. CONCLUSION: EA alleviated WAS-induced IBS in mice by promoting intestinal barrier functions and suppressing the expression of inflammatory cytokines.

[Moxibustion relieves colonic inflammation by up-regulating expression of miR-345-3p/miR-216a-5p and down-regulating NF-κB p65 in colonic tissue of rats with diarrhea-predominant irritable bowel syndrome].

OBJECTIVE: To observe the effect of moxibustion on the expression of miR-345-3p, miR-216a-5p and nuclear factor-κB p65(NF-κB p65) in colonic tissue of rats with diarrhea-predominant irritable bowel syndrome (IBS-D), so as to explore its anti-inflammatory mechanism in relieving IBS-D. METHODS: SD rats were randomly divided into normal control (n=12), model (n=12), moxibustion (n=12) and ammonium pyrrolidine dithiocarbamate (PDTC,n=12) groups. The IBS-D model was established by neonatal mother-child separation combined with acetic acid enema stimulation and chronic binding methods. The rats in the moxibustion group received moxibustion stimulation of "Tianshu"(ST25) and "Shangjuxu"(ST37) for 20 min, once a day, for 7 days, and those of the PDTC group received intraperitoneal injection of PDTC (50 mg·kg-1·d-1) once daily for 7 days. After the intervention, the body weight, loose stool rate and the minimum volume threshold of abdominal withdrawal reflex (AWR) were observed, and histopathological changes of colonic mucosa were observed by HE staining. The contents of interleukin-1ß (IL-1ß), interleukin-4 (IL-4), interleukin-6 (IL-6) and tumor necrosis factor α (TNF- α) in serum were measured by ELISA. The expression of miR-345-3p, miR-216a-5p and NF-κB p65 mRNA in the colon tissue were detected by quantitative real-time PCR, and the immunoactivities of IL-1ß, IL-6, TNF-α and NF-κB p65 in the colon tissue were determined by immunofluorescence histochemistry. RESULTS: Compared with the normal control group, the loose stool rate, contents of IL-1ß, IL-6 and TNF-α, experssion of NF-κB p65 mRNA and the immunoactivities of IL-1ß, IL-6, TNF-α and NF-κB p65 were significantly increased (P<0.01), whereas the body weight, minimum volume threshold of AWR, content of IL-4, and the relative expression of miR-345-3p and miR-216a-5p were remarkably decreased in the model group (P<0.01). In comparison with the model group, the loose stool rate, contents of IL-1ß, IL-6, TNF-α, expression of NF-κB p65 mRNA and the immunoactivities of IL-1ß, IL-6, TNF-α and NF-κB p65 were considerably down-regulated (P<0.01), while the content of IL-4 and the relative expressions of miR-345-3p and miR-216a-5p were obviously up-regulated in both moxibustion and PDTC groups (P<0.01, P<0.05). The content of IL-6 in serum was significantly lower in the PDTC group than in the moxibustion group (P<0.01). CONCLUSION: Moxibustion can reduce the level of intestinal inflammation and visceral hypersensitivity in IBS-D rats, which may be related to its functions in increasing the expression levels of miR-345-3p and miR-216a-5p and in inhibiting the expression of NF-κB p65, thus reducing the levels of inflammatory factors.

[Study on the mechanism of electroacupuncture repairing intestinal barrier via regulating mast cell in rats with diarrhea-predominant irritable bowel syndrome].

OBJECTIVE: To observe the effect of electroacupuncture (EA) on mast cell activation-related substances and intestinal barrier function in diarrhea-predominant irritable bowel syndrome (IBS-D) model rats, so as to explore its underlying mechanisms. METHODS: Thirty female SD rats were randomly divided into control group, model group and EA group, with 10 rats in each group. IBS-D model was established by chronic unpredictable mild stress combined with senna solution gavage. Rats in the EA group received EA treatment (2 Hz/15 Hz，0.1-1.0 mA) at "Zusanli" (ST36), "Taichong"(LR3) and "Tianshu"(ST25), 20 min per day, for a total of 14 days, with sides alternated daily. Visceral pain threshold was used to evaluate visceral hypersensitivity, diarrhea index was used to evaluate diarrhea degree. After all treatments, the pathological scores of colon were recorded after HE staining, the contents of cholecystokinin (CCK), substance P (SP), tryptase (TPS) and adenosine triphosphate (ATP) in colon were detected by ELISA, and the expressions of colonic tight junction protein ZO-1 and occludin were detected by Western blot. RESULTS: Compared with the control group, the visceral pain threshold, the expression levels of colonic ZO-1 and occludin proteins decreased (P<0.01), while the diarrhea index, the contents of colonic CCK, SP, TPS and ATP were significantly increased (P<0.01) in the model group. After intervention, in comparison with the model group, the visceral pain thre-shold, the protein expression levels of colonic ZO-1 and occludin protein increased (P<0.01), while the diarrhea index, the contents of colonic CCK, SP, TPS and ATP were significantly decreased (P<0.01) in the EA group. CONCLUSION: EA can significantly alleviate the symptoms of visceral hypersensitivity and diarrhea in IBS-D rats. Its mechanism may be related to down-regulating colonic CCK, SP, TPS and ATP, inhibiting mast cell activation and degranulation, and up-regulating colonic barrier tight junction proteins.

Acute Stress Regulates Sex-Related Molecular Responses in the Human Jejunal Mucosa: Implications for Irritable Bowel Syndrome.

Irritable bowel syndrome (IBS) is a prevalent gastrointestinal disorder linked to intestinal barrier dysfunction and life stress. We have previously reported that female sex per se determines an increased susceptibility to intestinal barrier dysfunction after cold pain stress (CPS). We aimed to identify sex-related molecular differences in response to CPS in healthy subjects to understand the origin of sex bias predominance in IBS. In 13 healthy males and 21 females, two consecutive jejunal biopsies were obtained using Watson's capsule, at baseline, and ninety minutes after CPS. Total mucosal RNA and protein were isolated from jejunal biopsies. Expression of genes related to epithelial barrier (CLDN1, CLDN2, OCLN, ZO-1, and ZO-3), mast cell (MC) activation (TPSAB1, SERPINA1), and the glucocorticoid receptor (NR3C1) were analyzed using RT-qPCR. NR3C1, ZO-1 and OCLN protein expression were evaluated through immunohistochemistry and western blot, and mucosal inflammation through MC, lymphocyte, and eosinophil numbering. Autonomic, hormonal, and psychological responses to CPS were monitored. We found an increase in jejunal MCs, a reduced CLDN1 and OCLN expression, and an increased CLDN2 and SERPINA1 expression 90 min after CPS. We also found a significant decrease in ZO-1, OCLN, and NR3C1 gene expression, and a decrease in OCLN protein expression only in females, when compared to males. CPS induced a significant increase in blood pressure, plasma cortisol and ACTH, and subjective stress perception in all participants. Specific and independent sex-related molecular responses in epithelial barrier regulation are unraveled by acute stress in the jejunum of healthy subjects and may partially explain female predominance in IBS.

Atractylodes-I Overcomes the Oxidative Stress-induced Colonic Mucosal Epithelial Cells Dysfunction to Prevent Irritable Bowel Syndrome Via Modulating the miR-34a-5p-LDHA Signaling Pathway.

BACKGROUND: Irritable bowel syndrome (IBS) is a known brain-gut disorder. Currently, the molecular and cellular mechanisms of IBS remain unclear. Atractylenolide-I (ATL-I) is a majorly bioactive component extracted from Rhizoma Atractylodes Macrocephalae. METHODS: Studies have revealed that ATL-I functioned as an anti-tumor drug in various cancers. However, the effects and molecular mechanisms of ATL-I on the pathological processes of colonic mucosal epithelial cells (CMECs) during IBS remain unclear. This study reports ATL-I effectively alleviated the oxidative stress-induced colonic mucosal epithelial cell dysfunction. In colonic mucosal tissues from IBS patients, we detected upregulated miR-34a-5p and suppressed glucose metabolism enzyme expressions. Under H2O2 treatment which mimics in vitro oxidative stress, miR-34a-5p was induced and glucose metabolism was inhibited in the colon mucosal epithelial cell line, NCM460. Meanwhile, ATL-I treatment effectively overcame the oxidative stress-induced miR-34a- 5p expression and glucose metabolism in NCM460 cells. RESULT: By bioinformatics analysis, Western blot and luciferase assay, we illustrated that miR-34a-5p directly targeted the 3'UTR region of glucose metabolism key enzyme, lactate dehydrogenase-A (LDHA) in colonic mucosal epithelial cells. Rescue experiments validated that miR-34a-5p inhibited glucose metabolism by targeting LDHA. Finally, we demonstrated that ATL-I treatment reversed the miR-34a-5p-inhibited glucose metabolism and -exacerbated colonic mucosal epithelial cell dysfunction under oxidative stress by modulating the miR-34a-5p-LDHA pathway. CONCLUSION: Summarily, our study reports the roles and mechanisms of ATL-I in the oxidative stress-induced colonic mucosal epithelial cell dysfunction during IBS through regulating the miR-34a-5p-LDHA-glucose metabolism axis.

A distinctive profile of family genetic risk scores in a Swedish national sample of cases of fibromyalgia, irritable bowel syndrome, and chronic fatigue syndrome compared to rheumatoid arthritis and major depression.

BACKGROUND: Functional somatic disorders (FSD) feature medical symptoms of unclear etiology. Attempts to clarify their origin have been hampered by a lack of rigorous research designs. We sought to clarify the etiology of the FSD by examining the genetic risk patterns for FSD and other related disorders. METHODS: This study was performed in 5 829 186 individuals from Swedish national registers. We quantified familial genetic risk for FSD, internalizing disorders, and somatic disorders in cases of chronic fatigue syndrome (CFS), fibromyalgia (FM), and irritable bowel syndrome (IBS), using a novel method based on aggregate risk in first to fifth degree relatives, adjusting for cohabitation. We compared these profiles with those of a prototypic internalizing psychiatric - major depression (MD) - and a somatic/autoimmune disorder: rheumatoid arthritis (RA). RESULTS: Patients with FM carry substantial genetic risks not only for FM, but also for pain syndromes and internalizing, autoimmune and sleep disorders. The genetic risk profiles for IBS and CFS are also widely distributed although with lower average risks. By contrast, genetic risk profiles of MD and RA are much more restricted to related conditions. CONCLUSION: Patients with FM have a relatively unique family genetic risk score profile with elevated genetic risk across a range of disorders that differs markedly from the profiles of a classic autoimmune disorder (RA) and internalizing disorder (MD). A similar less marked pattern of genetic risks was seen for IBS and CFS. FSD arise from a distinctive pattern of genetic liability for a diversity of psychiatric, autoimmune, pain, sleep, and functional somatic disorders.

Fecal Luminal Factors from Patients with Gastrointestinal Diseases Alter Gene Expression Profiles in Caco-2 Cells and Colonoids.

Previous in vitro studies have shown that the intestinal luminal content, including metabolites, possibly regulates epithelial layer responses to harmful stimuli and promotes disease. Therefore, we aimed to test the hypothesis that fecal supernatants from patients with colon cancer (CC), ulcerative colitis (UC) and irritable bowel syndrome (IBS) contain distinct metabolite profiles and establish their effects on Caco-2 cells and human-derived colon organoids (colonoids). The metabolite profiles of fecal supernatants were analyzed by liquid chromatography-mass spectrometry and distinguished patients with CC (n = 6), UC (n = 6), IBS (n = 6) and healthy subjects (n = 6). Caco-2 monolayers and human apical-out colonoids underwent stimulation with fecal supernatants from different patient groups and healthy subjects. Their addition did not impair monolayer integrity, as measured by transepithelial electrical resistance; however, fecal supernatants from different patient groups and healthy subjects altered the gene expression of Caco-2 monolayers, as well as colonoid cultures. In conclusion, the stimulation of Caco-2 cells and colonoids with fecal supernatants derived from CC, UC and IBS patients altered gene expression profiles, potentially reflecting the luminal microenvironment of the fecal sample donor. This experimental approach allows for investigating the crosstalk at the gut barrier and the effects of the gut microenvironment in the pathogenesis of intestinal diseases.

[Anti-inflammation effect of moxibustion for rats with diarrhea-predominant irritable bowel syndrome based on multiple miRNAs regulating NF-κB signal pathway].

OBJECTIVE: To observe the effect of moxibustion on the regulation of nuclear factor-kappa B (NF-κB) and inflammatory factors by multiple microRNAs (miRNAs) in rats with diarrhea-predominant irritable bowel syndrome (IBS-D), and to explore the anti-inflammatory mechanism of moxibustion on IBS-D. METHODS: Twelve of 52 newborn rats were randomly selected into a normal group. The remaining rats were made into IBS-D model. A total of 36 rats with successful model were randomly divided into a model group, a medication group and a moxibustion group, 12 rats in each group. The rats in the medication group were intraperitoneally injected with pyrrolidine dithiocarbamate (PDTC). The rats in the moxibustion group were treated with moxibustion at "Tianshu" (ST 25) and "Shangjuxu" (ST 37) for 20 min each time. All the intervention was given once a day for 7 days. Before and after modeling as well as after intervention, the body mass, loose stool rate and the minimum volume threshold of abdominal withdrawal reflex (AWR) were measured. After intervention, the contents of serum tumor necrosis factor α (TNF-α), interleukin (IL)-1ß and IL-8 were detected by ELISA method; the morphology of colon tissues was observed by HE staining, and the expressions of miR-155, miR-125b, miR-29b, miR-31, miR-18a and NF-κB p65 mRNA in colon tissues were detected by real-time PCR. The expressions of NF-κB p65, TNF-α, IL-1ß and IL-8 protein in colon tissues were detected by immunofluorescence. RESULTS: After modeling, the body mass and the minimum volume threshold of AWR in the model group were lower than those in the normal group (P<0.01); the rates of loose stool in the model group were higher than those in the normal group (P<0.01); after intervention, in the model group, the inflammatory infiltration of colon tissues was obvious, and the serum levels of TNF-α, IL-1 ß, IL-8 were higher than those in the normal group (P<0.05); the expression of miR-155, miR-125b, miR-29b, miR-31, miR-18a and NF-κB p65 mRNA in colon tissues was higher than that in the normal group (P<0.05); the protein expression of NF-κB p65, TNF-α, IL-1ß, IL-8 was also higher than that in the normal group (P<0.01). After intervention, the body mass and the minimum volume threshold of AWR in the medication group and the moxibustion group were both higher than those in the model group (P<0.05); the loose stool rate in the medication group and the moxibustion group were lower than those in model group (P<0.05); the inflammatory cells infiltration in the colon tissues was less, the serum levels of TNF-α, IL-1ß and IL-8 as well as the protein expression of NF-κB p65, TNF-α, IL-1ß and IL-8 in the colon tissues in the medication group and the moxibustion group were lower than those in the model group (P<0.05, P<0.01). The expression of miR-125b, miR-31, miR-18a and NF-κB p65 mRNA in the medication group were lower than those in the model group (P<0.05). The expression of miR-155, miR-125b, miR-29b, miR-31, miR-18a and NF-κB p65 mRNA in the moxibustion group were lower than those in the model group (P<0.05). The miR-155, miR-125b, miR-29b, miR-31, miR-18a were positively correlated with NF-κB p65 mRNA (0

Identification and potential functions of tRNA-derived small RNAs (tsRNAs) in irritable bowel syndrome with diarrhea.

IBS-D is a functional bowel disease without clear diagnostic markers and exact pathogenesis. Studies have proved that non-coding RNAs participate in IBS-D. However, tRNA-derived small RNAs (tsRNAs), as a new type of non-coding RNAs that are more suitable as markers, remain to be clarified in IBS-D. Hence, we focused on the identification and potential functions of tsRNAs in IBS-D. Intestinal biopsies were obtained from IBS-D patients and healthy volunteers, and twenty-eight differential tsRNAs were screened by high-throughput sequencing. The changes of tiRNA-His-GTG-001, tRF-Ser-GCT-113, and tRF-Gln-TTG-035 by q-PCR in expanded samples were consistent with the sequencing results. Meanwhile, target gene prediction and bioinformatics showed that the three differential tsRNAs may be involved in some key signal pathways, such as GABAergic synapse, tumor necrosis factor-α (TNF-α), etc. Their regulation on target genes were demonstrated through cell experiments and luciferase reporter assays. In addition, the receiver-operating characteristic (ROC) analysis showed that the three tsRNAs all could be used as candidate markers of IBS-D. The correlation analysis indicated they were related to the degree of abdominal pain, abdominal distension, and stool morphology. So, we believe that the abnormal tiRNA-His-GTG-001, tRF-Ser-GCT-113, and tRF-Gln-TTG-035 are related to the clinical symptoms of IBS-D, and can target regulate the important molecules of the brain-gut axis, even could be expected as potential biomarkers for the diagnosis and treatment of IBS-D.

Deciphering the synergistic network regulation of active components from SiNiSan against irritable bowel syndrome via a comprehensive strategy: Combined effects of synephrine, paeoniflorin and naringin.

BACKGROUND: SiNiSan (SNS) is an ancient Chinese herbal prescription, and the current clinical treatment of irritable bowel syndrome (IBS) is effective. In the previous study of the research team, the multi-functional co-synergism of SNS against IBS was presented. Some potential drug targets and candidate ligands were predicted. PURPOSE: This study attempts to explore the crucial ingredient combinations from SNS formula and reveal their synergistic mechanism for IBS therapy. MATERIALS AND METHODS: In present study, a comprehensive strategy was performed to reveal IBS related pathways and biological modules, and explore synergistic effects of the ingredients, including ADME (absorption, distribution, metabolism, excretion) screening, Text mining, Venn analysis, Gene ontology (GO) analysis, Pathway cluster analysis, Molecular docking, Network construction and Experimental verification in visceral hypersensitivity (VHS) rats. RESULTS: Three compressed IBS signal pathways were derived from ClueGO KEGG analysis of 63 IBS genes, including Neuroactive ligand-receptor interaction, Inflammatory mediator regulation of TRP (transient receptor potential) channels and Serotonergic synapse. A multi-module network, composed of four IBS therapeutic modules (psychological, inflammation, neuroendocrine and cross-talk modules), was revealed by Target-Pathway network. Nine kernel targets were considered closely associated with the IBS pathways, including ADRA2A, HTR2A, F2RL1, F2RL3, TRPV1, PKC, PKA, IL-1Β and NGF. In silico analysis revealed that three crucial ingredients (synephrine, paeoniflorin and naringin) were assumed to coordinate the network of those IBS therapeutic modules by acting on these kernel targets in the important pathways. In vivo experimental results showed that the crucial ingredient combinations synergistically affected the expressions of the kernel biological molecules, and improved the minimum capacity threshold of AWR in VHS rats. CONCLUSION: The study proposes the important IBS associated pathways and the network regulation mechanisms of the crucial ingredients. It reveals the multi-target synergistic effect of the crucial ingredient combinations for the novel therapy on IBS.

Pain Severity Correlates With Biopsy-Mediated Colonic Afferent Activation But Not Psychological Scores in Patients With IBS-D.

INTRODUCTION: Despite heterogeneity, an increased prevalence of psychological comorbidity and an altered pronociceptive gut microenvironment have repeatedly emerged as causative pathophysiology in patients with irritable bowel syndrome (IBS). Our aim was to study these phenomena by comparing gut-related symptoms, psychological scores, and biopsy samples generated from a detailed diarrhea-predominant IBS patient (IBS-D) cohort before their entry into a previously reported clinical trial. METHODS: Data were generated from 42 patients with IBS-D who completed a daily 2-week bowel symptom diary, the Hospital Anxiety and Depression score, and the Patient Health Questionnaire-12 Somatic Symptom score and underwent unprepared flexible sigmoidoscopy. Sigmoid mucosal biopsies were separately evaluated using immunohistochemistry and culture supernatants to determine cellularity, mediator levels, and ability to stimulate colonic afferent activity. RESULTS: Pain severity scores significantly correlated with the daily duration of pain (r = 0.67, P < 0.00001), urgency (r = 0.57, P < 0.0005), and bloating (r = 0.39, P < 0.05), but not with psychological symptom scores for anxiety, depression, or somatization. Furthermore, pain severity scores from individual patients with IBS-D were significantly correlated (r = 0.40, P < 0.008) with stimulation of colonic afferent activation mediated by their biopsy supernatant, but not with biopsy cell counts nor measured mediator levels. DISCUSSION: Peripheral pronociceptive changes in the bowel seem more important than psychological factors in determining pain severity within a tightly phenotyped cohort of patients with IBS-D. No individual mediator was identified as the cause of this pronociceptive change, suggesting that nerve targeting therapeutic approaches may be more successful than mediator-driven approaches for the treatment of pain in IBS-D.

The Colonic Mucosal MicroRNAs, MicroRNA-219a-5p, and MicroRNA-338-3p Are Downregulated in Irritable Bowel Syndrome and Are Associated With Barrier Function and MAPK Signaling.

BACKGROUND & AIMS: Alterations in microRNA (miRNA) and in the intestinal barrier are putative risk factors for irritable bowel syndrome (IBS). We aimed to identify differentially expressed colonic mucosal miRNAs, their targets in IBS compared to healthy controls (HCs), and putative downstream pathways. METHODS: Twenty-nine IBS patients (15 IBS with constipation [IBS-C], 14 IBS with diarrhea [IBS-D]), and 15 age-matched HCs underwent sigmoidoscopy with biopsies. A nCounter array was used to assess biopsy specimen-associated miRNA levels. A false discovery rate (FDR) < 10% was considered significant. Real-time polymerase chain reaction (PCR) was used to validate differentially expressed genes. To assess barrier function, trans-epithelial electrical resistance (TEER) and dextran flux assays were performed on Caco-2 intestinal epithelial cells that were transfected with miRNA-inhibitors or control inhibitors. Protein expression of barrier function associated genes was confirmed using western blots. RESULTS: Four out of 247 miRNAs tested were differentially expressed in IBS compared to HCs (FDR < 10%). Real-time PCR validation suggested decreased levels of miR-219a-5p and miR-338-3p in IBS (P = .026 and P = .004), and IBS-C (P = .02 and P = .06) vs. HCs as the strongest associations. Inhibition of miR-219a-5p resulted in altered expression of proteasome/barrier function genes. Functionally, miR-219a-5p inhibition enhanced the permeability of intestinal epithelial cells as TEER was reduced (25-50%, P < .05) and dextran flux was increased (P < .01). Additionally, inhibition of miR-338-3p in cells caused alterations in the mitogen-activated protein kinase (MAPK) signaling pathway genes. CONCLUSION: Two microRNAs that potentially affect permeability and visceral nociception were identified to be altered in IBS patients. MiR-219a-5p and miR-338-3p potentially alter barrier function and visceral hypersensitivity via neuronal and MAPK signaling and could be therapeutic targets in IBS.