Primary sclerosing cholangitis (PSC) and inflammatory bowel disease (IBD): a condition exemplifying the crosstalk of the gut-liver axis

Hepatic Nuclear Receptors in Cholestasis-to-Cholangiocarcinoma Pathology

Cholestasis, characterized by impaired bile flow, is associated with an increased risk of cholangiocarcinoma (CCA), a malignancy originating from the biliary epithelium and hepatocytes. Hepatic nuclear receptors (NRs) are pivotal in regulating bile acid and metabolic homeostasis, and their dysregulation is implicated in cholestatic liver diseases and the progression of liver cancer. This review elucidates the role of various hepatic NRs in the pathogenesis of cholestasis-to-CCA progression. It explores their impact on bile acid metabolism as well as their interactions with other signaling pathways implicated in CCA development. Additionally, it introduces available murine models of cholestasis/primary sclerosing cholangitis leading to CCA and discusses the clinical potential of targeting hepatic NRs as a promising approach for the prevention and treatment of cholestatic liver diseases and CCA. Understanding the complex interplay between hepatic NRs and cholestasis-to-CCA pathology holds promise for the development of novel preventive and therapeutic strategies for this devastating disease.

Mortality risk associated with MASLD, MASLD type and different cardiometabolic risk factors in IBD patients: A long-term prospective cohort study

PURPOSE

To examine the mortality risk associated with metabolic dysfunction-associated steatotic liver disease (MASLD), MASLD type, lean/non-lean MASLD and different cardiometabolic risk factors (CMRFs) in patients with inflammatory bowel disease (IBD) based on a long-term prospective cohort.

METHODS

Prevalent IBD patients at baseline who were free of alcoholic liver disease, cancer and hepatitis B/C virus seropositive were included (N=4622). MASLD, MASLD type [pure MASLD, MASLD with increased alcohol intake (MetALD)], lean/non-lean MASLD and CMRFs at baseline were defined according to the latest criteria proposed by AASLD and EASL. Primary outcome was all-cause mortality. Cox proportional hazard model was used to examine the association.

RESULTS

Overall, 1,763 (38.1%) were diagnosed with MASLD. During a median of 13.3-year follow-up, 451 all-cause deaths were identified. Compared with IBD-only patients, those with MASLD had a 58% excess risk of mortality (HR=1.58, 95%CI:1.07-2.32). Furthermore, as number of CMRFs increased in MASLD patients, mortality risk was significantly increased (Ptrend=0.005), with a 85% and 83% higher risk in MASLD with 3 CMRFs (HR=1.85, 95%CI:1.20-2.85) and ≥4 CMRFs (HR=1.83, 95%CI:1.16-2.89) versus IBD-only patients. Specifically, similar elevated mortality risk was observed in either pure MASLD (HR= 1.62, 95%CI:1.09-2.43) or MetALD (HR=2.03, 95%CI:1.24-3.32). Moreover, the excess mortality risk was both indicated in lean (HR=3.14, 95%CI:1.57-6.29) and non-lean MASLD (HR=1.67, 95%CI:1.12-2.48).

CONCLUSIONS

MASLD, either pure MASLD or MetALD, as well as lean/non-lean MASLD, is associated with increased mortality risk in IBD patients, with greater risk as number of cardiometabolic risk factors increased and evidently higher risk in lean MASLD patients.

A Closer Look into Autoimmune Liver Diseases

Autoimmune liver diseases involve a heterogeneous group of chronic inflammatory disorders, including autoimmune hepatitis, primary biliary cholangitis, and primary sclerosing cholangitis. Sometimes presented consistently as an overlapping syndrome, their pathogenesis is rather complex and has yet to be fully elucidated, despite extensive research efforts. This review article corroborates the molecular mechanisms of autoimmune liver diseases, as well as existing and potential therapeutic modalities.

Prevalence and bidirectional association between primary sclerosing cholangitis and Crohn's disease: A systematic review and meta-analysis

PURPOSE

This meta-analysis aimed to evaluating the prevalence of Crohn's disease in primary sclerosing cholangitis (PSC) and the incidence of primary sclerosing cholangitis in Crohn's disease (CD), along with their interrelation.

METHODS

An extensive search was conducted in the PubMed and Embase to identify available publications up to December 2023. Studies were included if they reported the prevalence of CD in PSC patients, or vice versa. Proportions were assessed using the DerSimonian and Laird method, followed by transformation via the Freeman-Tukey double inverse sine transformation. The quality of the included studies utilizing the Joanna Briggs Institute Critical Appraisal Checklist.

RESULTS

Based on quantitative analysis of 61 studies, the prevalence of PSC in patients with CD was 0.88% (95% CI: 0.53-1.30%). The prevalence of PSC in male CD patients was 0.45% (95% CI: 0.03-1.16%). In female CD patients, the prevalence was 0.51% (95% CI: 0.09-1.14%). The prevalence of CD with PSC was 11.27% (95% CI: 9.56-13.10%). The prevalence of CD in male PSC patients was 10.71% (95% CI: 7.42-14.50%). Among female PSC patients, the pooled prevalence of CD was 13.05% (95% CI: 11.05-15.19%).

CONCLUSIONS

We found a significant bidirectional association between PSC and CD, with a higher prevalence of CD in female with PSC compared to male. These findings provide important epidemiological data for clinical practice.

Effectiveness and safety of oral vancomycin for the treatment of inflammatory bowel disease associated with primary sclerosing cholangitis: a systematic review and pooled analysis

Background

Inflammatory bowel disease (IBD) occurs in up to 70%-80% of patients with primary sclerosing cholangitis (PSC). Oral vancomycin therapy (OVT) has been reported to be effective in the treatment of IBD associated with PSC (IBD-PSC).

Objectives

To examine the effectiveness and safety of OVT in the treatment of IBD-PSC by performing a systematic review and pooled analysis of the literature.

Design

We performed a systematic review and pooled analysis of studies reporting IBD clinical response to OVT in IBD-PSC.

Data sources and methods

A systematic search was conducted in Cochrane Library, Embase, Google Scholar, Medline, PubMed, Scopus, and Web of Science from database inception to June 3, 2024. We included adult and pediatric studies that reported on clinical response (defined as any improvement in IBD-related clinical symptoms) of IBD-PSC patients treated with OVT (including pre- and post-liver transplantation cohorts). Pooled analyses of OVT response and safety were performed.

Results

A total of 21 (open-label, non-controlled) studies including 290 patients with IBD-PSC treated with OVT were included. The median duration of OVT to treat IBD-PSC was 32.5 weeks (interquartile range (IQR): 19-83 weeks). The total daily dose of OVT ranged from 250 to 1500 mg. Concomitant treatment included the following: mesalamine in 14.5% (n = 42), advanced therapies in 10.7% (n = 31), and immunosuppressive agents in 14.1% (n = 41). Clinical response was noted in 47.6% (138/290) and clinical remission in 43.5% (100/230). The biochemical remission rate post-OVT was 68.8% (55/80) and endoscopic remission was 39.4% (80/203). Three studies (n = 11) reported no episodes of acute cholangitis while on OVT. Five studies (n = 69) reported an incidence rate of 8.7% of vancomycin-resistant enterococci post-OVT to treat IBD-PSC.

Conclusion

OVT was associated with clinical response/remission in almost half of patients with IBD-PSC with a favorable side effect profile. Further prospective randomized trials are needed to confirm the dosing, efficacy, treatment duration, and long-term safety of OVT for the treatment of IBD-PSC.

Trial registration

The study protocol was registered with PROSPERO a priori (no. CRD42023438341).

Pulmonary hypertension post-liver transplant: A case report

BACKGROUND

Liver transplantation (LTx) is vital in patients with end-stage liver disease, with metabolic dysfunction-associated steatotic liver disease being the most common indication. Primary sclerosing cholangitis (PSC) is an important indication. Portopulmonary hypertension, associated with portal hypertension, poses a significant perioperative risk, making pretransplant screening essential.

CASE SUMMARY

We report the case of a 41-year-old woman with PSC who developed severe pulmonary hypertension years after a successful LTx. She presented with worsening dyspnea on exertion and presyncope. Diagnostic evaluation confirmed severe precapillary pulmonary hypertension without evidence of recurrent portal hypertension. Initial management with Sildenafil and Macitentan led to a significant improvement in her symptoms, exercise capacity, and biomarkers. This case highlights the rare development of de novo pulmonary hypertension in a liver transplant recipient without recurrent portal hypertension, possibly linked to autoimmune processes or primary liver disease itself. The patient's positive response to the combination therapy underscores the importance of prompt diagnosis and aggressive management.

CONCLUSION

In conclusion, pulmonary arterial hypertension post-LTx is a rare but serious complication with a poor prognosis, necessitating further research to better understand its mechanisms and to develop effective strategies for prevention and treatment.

Incidence of Hepatobiliary Malignancies in Primary Sclerosing Cholangitis: Systematic Review and Meta-analysis

BACKGROUND & AIMS

Primary sclerosing cholangitis (PSC) is a known risk factor for hepatobiliary malignancies. We conducted a systematic review and meta-analysis of published studies to determine the incidence and risk factors for hepatobiliary malignancies in people with PSC.

METHODS

Pubmed and Embase databases were searched from inception to April 10, 2024, for cohort studies reporting data on the incidence of cholangiocarcinoma (CCA), hepatocellular carcinoma (HCC), or gallbladder cancer (GBC) in PSC. Pooled incidence rates with 95% confidence intervals (CIs) were estimated using a random effects model.

RESULTS

We identified 51 eligible studies involving 26,482 patients. The total follow-up was 221,258.1 person-years (PYs). The pooled incidence rates for overall PSC were 9.31 (95% CI, 6.84-12.67; I2 = 74%), 1.73 (95% CI, 1.20-2.51; I2 = 55%), and 1.06 (95% CI, 0.85-1.31; I2 = 0%) per 1000 PYs for CCA, HCC, and GBC, respectively. In patients with PSC with inflammatory bowel disease (IBD), rates were 7.16 (95% CI, 4.48-11.44; I2 = 96%), 2.19 (95% CI, 1.48-3.25; I2 = 58%), and 1.52 (95% CI, 1.21-1.90; I2 = 0%) per 1000 PYs, respectively. Subgroup analysis showed that the incidence of CCA was higher in smaller studies (<200 patients), and the incidence of HCC varied significantly by region (P = .03), with Oceania having the highest incidence and Europe having the lowest. Meta-regression determined that PSC-IBD was associated with HCC incidence.

CONCLUSION

The incidence of CCA in PSC is substantial, whereas HCC and GBC are rare. Patients with PSC-IBD may be at higher risk for HCC. These data should be validated in large, prospective studies, and may guide the development of evidence-based surveillance strategies for hepatobiliary malignancies in PSC.

Causal effect of primary sclerosing cholangitis on diffuse large B-cell lymphoma: A two-sample Mendelian randomized study

The connection between Primary sclerosing cholangitis (PSC) and lymphoma remains uncertain. To address this, Mendelian randomization (MR) was utilized to investigate the potential causal links between PSC and lymphoma. A 2-sample MR analysis was conducted utilizing summary-level data obtained from genome-wide association study datasets. Four complementary MR methods were performed, including inverse-variance weighting (IVW), MR-Egger, weighted median, and MR-robust adjusted profile score (MR-RAPS). Several sensitivity analyses were also employed to further validate the results. The results of IVW estimates showed that there was a potential causal association between PSC and diffuse large B-cell lymphoma (DLBCL) risk (OR = 1.138, 95% CI = 1.052-1.230, P = .001). No causal association was observed between PSC and other lymphoma subtypes. No horizontal and directional pleiotropy was observed in the MR studies. This study represents the inaugural utilization of MR analysis to investigate the causal associations between PSC and DLBCL. Further investigation is warranted to elucidate the underlying mechanism of this causal relationship.

Immunobiology of primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a chronic inflammatory progressive cholestatic liver disease. Genetic risk factors, the presence of autoantibodies, the strong clinical link with inflammatory bowel disease, and associations with other autoimmune disorders all suggest a pivotal role for the immune system in PSC pathogenesis. In this review, we provide a comprehensive overview of recent immunobiology insights in PSC. A particular emphasis is given to immunological concepts such as tissue residency and knowledge gained from novel technologies, including single-cell RNA sequencing and spatial transcriptomics. This review of the immunobiological landscape of PSC covers major immune cell types known to be enriched in PSC-diseased livers as well as recently described cell types whose biliary localization and contribution to PSC immunopathogenesis remain incompletely described. Finally, we emphasize the importance of time and space in relation to PSC heterogeneity as a key consideration for future studies interrogating the role of the immune system in PSC.

Navigating the pharmacotherapeutic management of comorbid inflammatory bowel disease and primary sclerosing cholangitis

INTRODUCTION

Primary sclerosing cholangitis (PSC) is the most specific hepatobiliary extraintestinal manifestation in inflammatory bowel disease (IBD). PSC ultimately has a poor prognosis, with disease progression resulting in liver cirrhosis and subsequent liver failure. While there is current data for the medical management of IBD, the optimal approach for concurrent PSC-IBD is unclear.

AREAS COVERED

This review focuses on the current literature of pharmacotherapy in the PSC-IBD population including anti-tumor necrosis factor agents, vedolizumab, JAK inhibitors, IL-12/23 inhibitors, and thiopurines. Regarding PSC-IBD, it focuses on effectiveness of IBD therapies on liver biochemistry and IBD activity as well as the advent of clinically relevant liver outcomes and safety. The authors also address the need for further advances in research.

EXPERT OPINION

The longer-term data for pharmacological management for IBD is well established. In the concomitant PSC-IBD population there is no drug to date that has effectively reduced disease related morbidity and mortality outcomes. There are limitations in the current, mostly retrospective data on IBD drugs in PSC-IBD with respect to samples sizes, heterogenous outcomes, and lack of a high-quality surrogate endpoint in PSC. However, current data for adalimumab offers encouraging results which require further exploration with larger prospective studies.

Bibliometric analysis of research on gut microbiota and bile acids: publication trends and research frontiers

The gut microbiota is widely regarded as a "metabolic organ" that could generate myriad metabolites to regulate human metabolism. As the microbiota metabolites, bile acids (BAs) have recently been identified as the critical endocrine molecules that mediate the cross-talk between the host and intestinal microbiota. This study provided a comprehensive insight into the gut microbiota and BA research through bibliometric analysis from 2003 to 2022. The publications on this subject showed a dramatic upward trend. Although the USA and China have produced the most publications, the USA plays a dominant role in this expanding field. Specifically, the University of Copenhagen was the most productive institution. Key research hotspots are the gut-liver axis, short-chain fatty acids (SCFAs), cardiovascular disease (CVD), colorectal cancer (CRC), and the farnesoid x receptor (FXR). The molecular mechanisms and potential applications of the gut microbiota and BAs in cardiometabolic disorders and gastrointestinal cancers have significant potential for further research.

It's Not Always Infections When It Comes to Resource-Poor Countries: A Fascinating Case Report

A patient's demographics often guide healthcare providers toward clues to a diagnosis. A recent travel history becomes an essential piece of the puzzle when there is a high suspicion of an infectious cause. When a patient walks into the hospital after having traveled to or from a resource-poor country with systemic afflictions, a physician's mind quickly jumps to infectious causes, and in most circumstances, it proves to be correct. We report an interesting case of a 28-year-old male from Guatemala who experienced acute gastrointestinal (GI) symptoms. Previous research in this field has shown that patients with inflammatory bowel disease (IBD) are prone to a slew of GI infections. Interestingly, our patient's presenting symptoms were initially attributed to "infections," but a thorough investigation revealed an unexpected twist of events. Our patient presented with multiple GI infections after the usual triggers, which masqueraded the coexistence of underlying primary sclerosing cholangitis and ulcerative colitis for a short course but were diagnosed promptly after a thorough workup.

Protective effect of zinc oxide nanoparticles synthesized using Cassia alata for DSS-induced ulcerative colitis in mice model

The most prevalent form of inflammatory bowel disease (IBD), ulcerative colitis (UC), is characterized by persistent inflammation of the colorectal mucosa. It is asymptomatic, whereas Crohn's disease (CD) causes patchy lesions in the gastrointestinal tract. Men and women suffer equally from ulcerative colitis, which usually strikes in the second and third decades of life and becomes more common in senior citizens. In the present study, we produced zinc oxide nanoparticles using the natural herbal plant, Cassia alata. Zinc oxide nanoparticles have remarkable antimicrobial and antitumor benefits in the field of biomedical science. Furthermore, the synthesized zinc oxide nanoparticles (ZnO NPs) were characterized using UV, XRD, FTIR, and SEM analyses. The XRD analysis confirmed the crystallite nature and purity of the synthesized nanoparticles. Zinc oxide nanoparticles with a uniform size and partially agglomerated morphology were verified by SEM analysis. We investigated the protective effects of environmentally friendly zinc oxide nanoparticles in dextran sodium sulfate-induced ulcerative colitis mouse models. Green synthesized Cassia alata zinc oxide nanoparticles (CA ZnO NPs) reversed weight loss, disease activity index, colon shortening, and colon histological damage. Zinc oxide nanoparticles reduce hypersensitivity, oxidative stress, and inflammation, and protect the mucosal layer. Green synthesized CA ZnO NPs demonstrated protection against dextran sodium sulfate-induced ulcerative colitis via anti-inflammatory activity.

Haplotype Analysis Reveals Pleiotropic Disease Associations in the HLA Region

The human leukocyte antigen (HLA) region plays an important role in human health through involvement in immune cell recognition and maturation. While genetic variation in the HLA region is associated with many diseases, the pleiotropic patterns of these associations have not been systematically investigated. Here, we developed a haplotype approach to investigate disease associations phenome-wide for 412,181 Finnish individuals and 2,459 traits. Across the 1,035 diseases with a GWAS association, we found a 17-fold average per-SNP enrichment of hits in the HLA region. Altogether, we identified 7,649 HLA associations across 647 traits, including 1,750 associations uncovered by haplotype analysis. We find some haplotypes show trade-offs between diseases, while others consistently increase risk across traits, indicating a complex pleiotropic landscape involving a range of diseases. This study highlights the extensive impact of HLA variation on disease risk, and underscores the importance of classical and non-classical genes, as well as non-coding variation.

Genetic association and causal relationship between multiple modifiable risk factors and autoimmune liver disease: a two-sample mendelian randomization study

BACKGROUND

The intricate etiology of autoimmune liver disease (AILD) involves genetic, environmental, and other factors that yet to be completely elucidated. This study comprehensively assessed the causal association between genetically predicted modifiable risk factors and AILD by employing Mendelian randomization.

METHODS

Genetic variants associated with 29 exposure factors were obtained from genome-wide association studies (GWAS). Genetic association data with autoimmune hepatitis (AIH), primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) were also obtained from publicly available GWAS. Univariate and multivariate Mendelian randomization analyses were performed to identify potential risk factors for AILD.

RESULTS

Genetically predicted rheumatoid arthritis (RA) (OR = 1.620, 95%CI 1.423-1.843, P = 2.506 × 10- 13) was significantly associated with an increased risk of AIH. Genetically predicted smoking initiation (OR = 1.637, 95%CI 1.055-2.540, P = 0.028), lower coffee intake (OR = 0.359, 95%CI 0.131-0.985, P = 0.047), cholelithiasis (OR = 1.134, 95%CI 1.023-1.257, P = 0.017) and higher C-reactive protein (CRP) (OR = 1.397, 95%CI 1.094-1.784, P = 0.007) were suggestively associated with an increased risk of AIH. Genetically predicted inflammatory bowel disease (IBD) (OR = 1.212, 95%CI 1.127-1.303, P = 2.015 × 10- 7) and RA (OR = 1.417, 95%CI 1.193-1.683, P = 7.193 × 10- 5) were significantly associated with increased risk of PBC. Genetically predicted smoking initiation (OR = 1.167, 95%CI 1.005-1.355, P = 0.043), systemic lupus erythematosus (SLE) (OR = 1.086, 95%CI 1.017-1.160, P = 0.014) and higher CRP (OR = 1.199, 95%CI 1.019-1.410, P = 0.028) were suggestively associated with an increased risk of PBC. Higher vitamin D3 (OR = 0.741, 95%CI 0.560-0.980, P = 0.036) and calcium (OR = 0.834, 95%CI 0.699-0.995, P = 0.044) levels were suggestive protective factors for PBC. Genetically predicted smoking initiation (OR = 0.630, 95%CI 0.462-0.860, P = 0.004) was suggestively associated with a decreased risk of PSC. Genetically predicted IBD (OR = 1.252, 95%CI 1.164-1.346, P = 1.394 × 10- 9), RA (OR = 1.543, 95%CI 1.279-1.861, P = 5.728 × 10- 6) and lower glycosylated hemoglobin (HbA1c) (OR = 0.268, 95%CI 0.141-0.510, P = 6.172 × 10- 5) were positively associated with an increased risk of PSC.

CONCLUSIONS

Evidence on the causal relationship between 29 genetically predicted modifiable risk factors and the risk of AIH, PBC, and PSC is provided by this study. These findings provide fresh perspectives on the management and prevention strategies for AILD.

Exploration of the core pathway of inflammatory bowel disease complicated with metabolic fatty liver and two-sample Mendelian randomization study of the causal relationships behind the disease

Background

Inflammatory bowel disease (IBD) is often associated with complex extraintestinal manifestations. The incidence of nonalcoholic fatty liver disease (NAFLD) in IBD populations is increasing yearly. However, the mechanism of interaction between NAFLD and IBD is not clear. Consequently, this study aimed to explore the common genetic characteristics of IBD and NAFLD and identify potential therapeutic targets.

Materials and methods

Gene chip datasets for IBD and NAFLD were obtained from the Gene Expression Omnibus (GEO) database. Weighted gene co-expression network analysis (WGCNA) was performed to identify modules in those datasets related to IBD and NAFLD. ClueGO was used for biological analysis of the shared genes between IBD and NAFLD. Based on the Human MicroRNA Disease Database (HMDD), microRNAs (miRNAs) common to NAFLD and IBD were obtained. Potential target genes for the miRNAs were predicted using the miRTarbase, miRDB, and TargetScan databases. Two-sample Mendelian randomization (MR) and two-way MR were used to explore the causal relationship between Interleukin-17 (IL-17) and the risk of IBD and NAFLD using data from GWAS retrieved from an open database.

Results

Through WGCNA, gene modules of interest were identified. GO enrichment analysis using ClueGO suggested that the abnormal secretion of chemokines may be a common pathophysiological feature of IBD and NAFLD, and that the IL-17-related pathway may be a common key pathway for the pathological changes that occur in IBD and NAFLD. The core differentially expressed genes (DEGs) in IBD and NAFLD were identified and included COL1A1, LUM, CCL22, CCL2, THBS2, COL1A2, MMP9, and CXCL8. Another cohort was used for validation. Finally, analysis of the miRNAs identified potential therapeutic targets. The MR results suggested that although there was no causal relationship between IBD and NAFLD, there were causal relationships between IL-17 and IBD and NAFLD.

Conclusion

We established a comorbid model to explain the potential mechanism of IBD with NAFLD and identified the chemokine-related pathway mediated by cytokine IL-17 as the core pathway in IBD with NAFLD, in which miRNA also plays a role and thus provides potential therapeutic targets.

Gut Microbiota in Primary Sclerosing Cholangitis: From Prognostic Role to Therapeutic Implications

BACKGROUND

Primary sclerosing cholangitis (PSC) is a chronic cholestatic disease of unknown etiology characterized by biliary inflammation and periductal fibrosis. The gut microbiota plays a crucial role in the pathogenesis of PSC by regulating bile acid metabolism, inflammation, and immune response. On the other hand, liver disease progression affects the composition of the gut microbiota, fostering these mechanisms in a mutual detrimental way.

SUMMARY

Recent evidences described a specific pro-inflammatory microbial signature in PSC patients, with an overall reduced bacterial diversity and the loss of beneficial metabolites such as short-chain fatty acids. As effective therapies for PSC are still lacking, targeting the gut microbiota offers a new perspective in the management of this disease. To date, antibiotics, fecal microbiota transplantation, and probiotics are the most studied gut microbiota-targeted intervention in PSC, but new potential strategies such as vaccines and bacteriophages represent possible future therapeutic horizons.

KEY MESSAGES

In this review, we focus on the role of the gut microbiota in PSC, considering its pathogenetic and prognostic role and the therapeutic implications.

Causal effects from inflammatory bowel disease on liver function and disease: a two-sample Mendelian randomization study

Background

Accumulating evidence has shown that patients with inflammatory bowel disease (IBD) have liver function abnormalities and are susceptible to liver diseases. However, the existence of a causal relationship between IBD and liver function or disease remains unclear.

Methods

A two-sample Mendelian randomization (MR) analysis was performed using genetic associations from publicly available genome-wide association studies (GWAS). These associations encompass ulcerative colitis (UC), Crohn's disease (CD), liver function traits, and liver disease phenotypes. The liver function traits comprised hepatic biochemistries, percent liver fat, and liver iron content from the UK Biobank. Furthermore, the liver disease phenotypes included cholelithiasis, non-alcoholic fatty liver disease (NAFLD), primary sclerosing cholangitis (PSC), and primary biliary cholangitis (PBC) in cohorts of European ancestry. The primary estimation used the inverse-variance weighted method, with GWAS of C-reactive protein (CRP) in the UK Biobank serving as a positive control outcome.

Results

Genetically predicted UC is causally associated with decreased levels of albumin (ALB) and liver iron content, while genetically predicted CD is causally associated with increased levels of alkaline phosphatase (ALP). Moreover, genetically predicted UC or CD increases the risk of PSC, and CD increases the risk of PBC. Neither UC nor CD causally increases the risk of cholelithiasis and NAFLD.

Conclusion

UC affects the levels of ALB and liver iron content, while CD affects the levels of ALP. Both UC and CD increase the risk of PSC, and CD increases the risk of PBC.

Probiotic Pediococcus pentosaceus Li05 Improves Cholestasis through the FXR-SHP and FXR-FGF15 Pathways

Primary sclerosing cholangitis (PSC), a rare chronic cholestatic liver disease, is characterized by intrahepatic or extrahepatic strictures accompanied by biliary fibrosis. So far, there are no effective therapies to slow down the progression of this disease. Farnesoid X receptors (FXRs) are ligand-activated transcription factors involved in the control of bile acid (BA) synthesis and enterohepatic circulation. Therefore, targeting FXRs holds promise as a potential approach for treating PSC. Pediococcus pentosaceus Li05 is a probiotic that was isolated from healthy volunteers and has previously been shown to have an anti-inflammatory effect in DSS-induced colitis. In this study, we established a 3,5-diethoxycarbonyl-1,4-Dihydrocollidine (DDC)-induced cholestasis mouse model and investigated the effects of Pediococcus pentosaceus Li05 on PSC. Our findings revealed that administration of Li05 significantly attenuated liver damage, hepatic inflammation, and fibrosis, as well as bile duct hyperplasia. Li05 activated the hepatic FXR-SHP and ileal FXR-FGF15 signaling pathways to decrease the expression of Cyp7a1. In addition, the Li05-modulated gut microbiota structure especially improved the abundance of 7α-dehydroxylation bacteria like Eubacterium. The intervention of Li05 also improved the intestinal barrier and reduced bacterial endotoxin translocation. Based on these findings, Li05 shows promise for future application as a therapeutic strategy for cholestasis.

Treatment of primary sclerosing cholangitis combined with inflammatory bowel disease

Primary sclerosing cholangitis (PSC) is a progressive cholestatic, inflammatory, and fibrotic disease that is strongly associated with inflammatory bowel disease (IBD). PSC-IBD represents a unique disease entity and patients with this disease have an increased risk of malignancy development, such as colorectal cancer and cholangiocarcinoma. The pathogenesis of PSC-IBD involves genetic and environmental factors such as gut dysbiosis and bile acids alteration. However, despite the advancement of disease characteristics, no effective medical therapy has proven to have a significant impact on the prognosis of PSC. The treatment options for patients with PSC-IBD do not differ from those for patients with PSC alone. Potential candidate drugs have been developed based on the pathogenesis of PSC-IBD, such as those that target modulation of bile acids, inflammation, fibrosis, and gut dysbiosis. In this review, we summarize the current medical treatments for PSC-IBD and the status of new emerging therapeutic agents.