Functions of the Gallbladder

Alteration of ascending colon mucosal microbiota in patients after cholecystectomy

BACKGROUND

Cholecystectomy is a successful treatment option for gallstones, although the incidence of colorectal cancer (CRC) has notably increased in post-cholecystectomy (PC) patients. However, it remains uncertain whether the altered mucosal microbiota in the ascending colon is related.

AIM

To investigate the potential correlation between gut microbiota and the surgical procedure of cholecystectomy.

METHODS

In total, 30 PC patients and 28 healthy controls underwent colonoscopies to collect mucosal biopsy samples. PC patients were divided based on their clinical features. Then, 16S-rRNA gene sequencing was used to analyze the amplicon, alpha diversity, beta diversity, and composition of the bacterial communities. Additionally, the Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) database, sourced from the Kyoto Encyclopedia of Genes and Genomes, was used to predict the functional capabilities of the bacteria.

RESULTS

PC patients were comparable with healthy controls. However, PC patients older than 60 years had a distinct composition compared to those under 60 years old. Bacteroidetes richness was considerably higher at the phylum level in PC patients. Bacteroides, Parabacteroides, and Bilophila were more abundant in the PC group than in the control group. Furthermore, PC patients exhibited greater enrichment in metabolic pathways, specifically those related to lipopolysaccharide biosynthesis and vancomycin group antibiotic production, than controls.

CONCLUSION

This study indicated that the mucosal microbiota in PC patients was altered, perhaps offering new perspectives on the treatment possibilities for CRC and diarrhea following cholecystectomy.

Proteomics and metabolomics analyses of urine for investigation of gallstone disease in a high-altitude area

BACKGROUND

The incidence of gallstones is high in Qinghai Province. However, the molecular mechanisms underlying the development of gallstones remain unclear.

METHODS

In this study, we collected urine samples from 30 patients with gallstones and 30 healthy controls. The urine samples were analysed using multi-omics platforms. Proteomics analysis was conducted using data-independent acquisition, whereas metabolomics analysis was performed using liquid chromatography-mass spectrometry (LC-MS).

RESULTS

Among the patients with gallstones, we identified 49 down-regulated and 185 up-regulated differentially expressed proteins as well as 195 up-regulated and 189 down-regulated differentially expressed metabolites. Six pathways were significantly enriched: glycosaminoglycan degradation, arginine and proline metabolism, histidine metabolism, pantothenate and coenzyme A biosynthesis, drug metabolism-other enzymes, and the pentose phosphate pathway. Notably, 10 differentially expressed proteins and metabolites showed excellent predictive performance and were selected as potential biomarkers.

CONCLUSION

The findings of our metabolomics and proteomics analyses provide new insights into novel biomarkers for patients with cholelithiasis in high-altitude areas.

Bitter tastants relax the mouse gallbladder smooth muscle independent of signaling through tuft cells and bitter taste receptors

Disorders of gallbladder motility can lead to serious pathology. Bitter tastants acting upon bitter taste receptors (TAS2R family) have been proposed as a novel class of smooth muscle relaxants to combat excessive contraction in the airways and other organs. To explore whether this might also emerge as an option for gallbladder diseases, we here tested bitter tastants for relaxant properties and profiled Tas2r expression in the mouse gallbladder. In organ bath experiments, the bitter tastants denatonium, quinine, dextromethorphan, and noscapine, dose-dependently relaxed the pre-contracted gallbladder. Utilizing gene-deficient mouse strains, neither transient receptor potential family member 5 (TRPM5), nor the Tas2r143/Tas2r135/Tas2r126 gene cluster, nor tuft cells proved to be required for this relaxation, indicating direct action upon smooth muscle cells (SMC). Accordingly, denatonium, quinine and dextromethorphan increased intracellular calcium concentration preferentially in isolated gallbladder SMC and, again, this effect was independent of TRPM5. RT-PCR revealed transcripts of Tas2r108, Tas2r126, Tas2r135, Tas2r137, and Tas2r143, and analysis of gallbladders from mice lacking tuft cells revealed preferential expression of Tas2r108 and Tas2r137 in tuft cells. A TAS2R143-mCherry reporter mouse labeled tuft cells in the gallbladder epithelium. An in silico analysis of a scRNA sequencing data set revealed Tas2r expression in only few cells of different identity, and from in situ hybridization histochemistry, which did not label distinct cells. Our findings demonstrate profound tuft cell- and TRPM5-independent relaxing effects of bitter tastants on gallbladder smooth muscle, but do not support the concept that these effects are mediated by bitter receptors.

Cholecystohepatic shunt pathway reduces secondary bile acid accumulation to enhance natural killer T cell-mediated anti-hepatocellular carcinoma immunity

BACKGROUND AND AIM

The impact of cholecystectomy, which blocks the cholecystohepatic shunt pathway (CHSP), on the prognosis of patients with hepatocellular carcinoma (HCC) is unclear. Hepatic secondary bile acids (BAs) inhibit natural killer T (NKT) cell-mediated immunity against HCC, and the regulation of homeostasis of hepatic secondary BAs is controlled by the CHSP. However, the influence of CHSP on NKT cell-mediated immunity against HCC remains unclear.

METHODS

The clinical data of hospitalized patients undergoing HCC resection were collected. Meanwhile, an in situ HCC mouse model was established, and the CHSP was augmented using oleanolic acid (OA).

RESULTS

After 1:1 propensity score matching, Cox regression analysis revealed that cholecystectomy was an independent risk factor for HCC recurrence after hepatectomy (P = 0.027, hazard ratio: 1.599, 95% confidence interval: 1.055-2.422). Experimentally, when OA enhanced CHSP, a significant decrease was observed in the accumulation of secondary BAs in the livers of mice. Additionally, a significant increase was observed in the levels of C-X-C ligand 16 and interferon γ in the serum and tumor tissues. Further, the percentage of C-X-C receptor 6 (+) NKT cells in the tumor tissues increased significantly, and the growth of liver tumors was inhibited.

CONCLUSIONS

This clinical study revealed that cholecystectomy promoted the recurrence after radical hepatectomy in patients with HCC. Preserving the normal-functioning gallbladder as much as possible during surgery may be beneficial to the patient's prognosis. Further investigation into the mechanism revealed that CHSP enhanced NKT cell-mediated immunity against HCC by reducing the hepatic accumulation of secondary BAs.

Safety and Efficacy of Ultrasound-Guided Radiofrequency Ablation in the Treatment of Gallbladder Polyps

RATIONALE AND OBJECTIVES

To investigate the safety and efficacy of ultrasound-guided radiofrequency ablation (RFA) in the treatment of gallbladder polyps.

MATERIALS AND METHODS

A retrospective analysis was conducted on the medical records of 296 patients diagnosed with gallbladder polyps. The study observed the changes in lesions post-procedure within the ablation group, and compared whether there was a difference in the gallbladder contraction rate in patients before and after ablation. It also compared the liver function indicators before and after surgery, some indicators during the periprocedural period, and the incidence of complications in two groups of patients.

RESULTS

In the ablation group, all lesions (84/84) were completely ablated, and the absorption effect of the ablation lesions was good after the ablation. No significant differences were observed in the gallbladder contraction rate before ablation compared to 1 month and 3 months post-ablation (p > 0.05). After the operation, statistically significant differences were observed in ALT and TP between the two groups (all p < 0.05). Significant differences were observed between the two groups in terms of hospital stay, procedural time, postprocedural mobilization time, postprocedural exhaust time, postprocedural eating time, and VAS score on postprocedural day 3 (all p < 0.05). There was no significant difference in the incidence of complications between the two groups (x2=0.477，p = 0.490).

CONCLUSION

Our findings demonstrate that ultrasound-guided RFA is a safe, effective, and feasible treatment for gallbladder polyps, as it not only effectively eliminates the polyps but also preserves the physiological functions of the gallbladder.

Impact of cholecystectomy on the gut-liver axis and metabolic disorders

Cholecystectomy is considered as a safe procedure to treat patients with gallstones. However, epidemiological studies highlighted an association between cholecystectomy and metabolic disorders, such as type 2 diabetes mellitus and metabolic dysfunction-associated steatotic liver disease (MASLD), independently of the gallstone disease. Following cholecystectomy, bile acids flow directly from the liver into the intestine, leading to changes in the entero-hepatic circulation of bile acids and their metabolism. The changes in bile acids metabolism impact the gut microbiota. Therefore, cholecystectomized patients display gut dysbiosis characterized by a reduced diversity, a loss of bacteria producing short-chain fatty acids and an increase in pro-inflammatory bacteria. Alterations of both bile acids metabolism and gut microbiota occurring after cholecystectomy can promote the development of metabolic disorders. In this review, we discuss the impact of cholecystectomy on bile acids and gut microbiota and its consequences on metabolic functions.

Advances in the pathophysiology, diagnosis and management of chronic diarrhoea from bile acid malabsorption: a systematic review

Bile acid malabsorption (BAM) is an important disorder of digestive pathophysiology as it generates chronic diarrhoea. This condition originates from intricate pathways involving bile acid synthesis and metabolism in the liver and gut, the composition of gut microbiota, enterohepatic circulation and key receptors as farnesoid X receptor (FXR), fibroblast growth factor receptor 4 (FGFR4), and the G-protein bile acid receptor-1 (GPBAR-1). Although symptoms can resemble those related to disorders of gut brain interaction, accurate diagnosis of BAM may greatly benefit the patient. The empiric diagnosis of BAM is primarily based on the clinical response to bile acid sequestrants. Specific tests including the 48-hour fecal bile acid test, serum levels of 7α-hydroxy-4-cholesten-3-one (C4) and fibroblast growth factor 19 (FGF19), and the 75Selenium HomotauroCholic Acid Test (SeHCAT) are not widely available. Nevertheless, lack of diagnostic standardization of BAM may account for poor recognition and delayed management. Beyond bile acid sequestrants, therapeutic approaches include the use of FXR agonists, FGF19 analogues, glucagon-like peptide-1 (GLP-1) receptor agonists, and microbiota modulation. These novel agents can best make their foray into the therapeutic armamentarium if BAM does not remain a diagnosis of exclusion. Ignoring BAM as a specific condition may continue to contribute to increased healthcare costs and reduced quality of life. Here, we aim to provide a comprehensive review of the pathophysiology, diagnosis, and management of BAM.

Effect of Laparoscopic Cholecystectomy on 25- Hydroxyvitamin D Levels and Bone Mineral Density in Post Menopausal Women

Background Laparoscopic cholecystectomy (LC) is the gold standard management for benign gallbladder diseases. It has been observed that there is alteration in vitamin D levels and bone mineral density after cholecystectomy due to altered enterohepatic circulation.With increase in average age expectancy of the population, low levels of vitamin D levels and osteoporosis after cholecystectomies might cause increased health care burden.Methods A prospective observational study was planned between 1st Jan 2022 to 30th Jun 2023 in the Department of General Surgery at PGIMER Chandigarh, a tertiary care hospital in north India. One hundred and three post-menopausal women who underwent LC and met the inclusion and exclusion criteria were included in the study. All participants underwent estimation of vitamin D and bone mineral density preoperatively and 3rdpost operative month (POM).Results The mean age of the patients was58.46 ± 7.44. Pain abdomen was present in 68(66%) patients, 18 had epigastric discomfort and 17 had dyspepsia. The mean levels of vit D decreased from21.92 at the baseline to 20.12 at 3rd POM(P < 0.001). There was significant change in t score Femoral Neck (-1.12 vs -1.15, P < 0.001) andLumbar spine L1-L4 -1.98 vs-1.98 (P = 0.033). z-Scores of the Femoral Neck were -0.34 vs -0.54 (p < 0.001) and of Lumbar spine L1-L4 were -0.95 vs 1.02 (P < 0.001). The decrease in fracture risk for the femoral neck(p= 0.344) and the lumbar spine (P = 0.223) were not statistically significant.Conclusion There is significant decrease in vitamin D and BMD level after LC in post-menopausal females.

Gallbladder dysfunction caused by MYPT1 ablation triggers cholestasis-induced hepatic fibrosis in mice

BACKGROUND

The incidence of gallbladder diseases is as high as 20%, but whether gallbladder diseases contribute to hepatic disorders remains unknown.

METHODS

Here, we established an animal model of gallbladder dysfunction and assessed the role of a diseased gallbladder in cholestasis-induced hepatic fibrosis (CIHF).

RESULTS

Mice with smooth muscle-specific deletion of Mypt1, the gene encoding the main regulatory subunit of myosin light chain phosphatase (myosin phosphatase target subunit 1 [MYPT1]), had apparent dysfunction of gallbladder motility. This dysfunction was evidenced by abnormal contractile responses, namely, inhibited cholecystokinin 8-mediated contraction and nitric oxide-resistant relaxation. As a consequence, the gallbladder displayed impaired bile filling and biliary tract dilation comparable to the alterations in CIHF. Interestingly, the mutant animals also displayed CIHF features, including necrotic loci by the age of 1 month and subsequently exhibited progressive fibrosis and hyperplastic/dilated bile ducts. This pathological progression was similar to the phenotypes of the animal model with bile duct ligation and patients with CIHF. The characteristic biomarker of CIHF, serum alkaline phosphatase activity, was also elevated in the mice. Moreover, we observed that the myosin phosphatase target subunit 1 protein level was able to be regulated by several reagents, including lipopolysaccharide, exemplifying the risk factors for gallbladder dysfunction and hence CIHF.

CONCLUSIONS

We propose that gallbladder dysfunction caused by myosin phosphatase target subunit 1 ablation is sufficient to induce CIHF in mice, resulting in impairment of the bile transport system.

The Impact of Cholecystectomy in Patients with Post-Bariatric Surgery Hypoglycemia

BACKGROUND

Metabolic surgery is the foremost treatment for obesity and its associated medical conditions. Nonetheless, post-bariatric hypoglycemia (PBH) emerges as a prevalent complication. PBH pathophysiology implicates heightened insulin and glucagon-like peptide 1 (GLP-1) levels, with bile acids (BA) contributing to GLP-1 release. A plausible association exists between cholecystectomy and PBH, which is attributed to alterations in BA metabolism and ensuing hormonal responses. The objective of this retrospective cohort study was to evaluate the impact of cholecystectomy on PBH pharmacological treatment, diagnostic timelines and metabolic parameters.

MATERIALS AND METHODS

Patients diagnosed with PBH after bariatric surgery were evaluated based on their history of cholecystectomy. Demographic, anthropometric and clinical data were collected. Mixed meal tolerance tests (MMTT) results were compiled to assess metabolic responses.

RESULTS

Of the 131 patients with PBH included in the study, 29 had prior cholecystectomy. The time to PBH diagnosis was similar across groups. Patients with prior cholecystectomy required higher doses of acarbose (p = 0.046), compared to those without prior cholecystectomy. Additionally, MMTT revealed higher insulin (t = 60 min: p = 0.010 and t = 90 min: p = 0.034) and c-peptide levels (t = 60 min: p = 0.008) and greater glycemic variability in patients with prior cholecystectomy (p = 0.049), highlighting the impact of cholecystectomy on glucose metabolism.

CONCLUSION

Our study offers novel insights into PBH pharmacotherapy, indicating that PBH patients with a history of cholecystectomy require elevated doses of acarbose for symptom control than PBH patients without such surgical history. Furthermore, our findings underscore the pivotal role of hyperinsulinism in PBH aetiology, emphasizing the significance of the BA-GLP-1-insulin axis.

Development and validation of a nomogram model for predicting the risk of gallstone recurrence after gallbladder-preserving surgery

BACKGROUND

The high incidence of gallstone recurrence was a major concern for laparoscopic gallbladder-preserving surgery. This study aimed to investigate the risk factors for gallstone recurrence after gallbladder-preserving surgery and to establish an individualized nomogram model to predict the risk of gallstone recurrence.

METHODS

The clinicopathological and follow-up data of 183 patients who were initially diagnosed with gallstones and treated with gallbladder-preserving surgery at our hospital from January 2012 to January 2019 were retrospectively collected. The independent predictive factors for gallstone recurrence following gallbladder-preserving surgery were identified by multivariate logistic regression analysis. A nomogram model for the prediction of gallstone recurrence was constructed based on the selected variables. The C-index, receiver operating characteristic (ROC) curve and calibration curve were used to evaluate the predictive power of the nomogram model for gallstone recurrence.

RESULTS

During the follow-up period, a total of 65 patients experienced gallstone recurrence, and the recurrence rate was 35.5%. Multivariate logistic regression analysis revealed that the course of gallstones > 2 years [odds ratio (OR) = 2.567, 95% confidence interval (CI): 1.270-5.187, P = 0.009], symptomatic gallstones (OR = 2.589, 95% CI: 1.059-6.329, P = 0.037), multiple gallstones (OR = 2.436, 95% CI: 1.133-5.237, P = 0.023), history of acute cholecystitis (OR = 2.778, 95% CI: 1.178-6.549, P = 0.020) and a greasy diet (OR = 2.319, 95% CI: 1.186-4.535, P = 0.014) were independent risk factors for gallstone recurrence after gallbladder-preserving surgery. A nomogram model for predicting the recurrence of gallstones was established based on the above five variables. The results showed that the C-index of the nomogram model was 0.692, suggesting it was valuable to predict gallstone recurrence. Moreover, the calibration curve showed good consistency between the predicted probability and actual probability.

CONCLUSIONS

The nomogram model for the prediction of gallstone recurrence might help clinicians develop a proper treatment strategy for patients with gallstones. Gallbladder-preserving surgery should be cautiously considered for patients with high recurrence risks.

Associations of gallbladder and gallstone parameters with clinical outcomes in patients with cirrhosis

Background

Morphologic changes in the gallbladder and gallstones are common in cirrhotic patients, but their associations with outcomes of cirrhotic patients are unclear.

Methods

We retrospectively enrolled 206 cirrhotic patients and measured their gallbladder length and width, gallbladder wall thickness, presence of gallstones, and gallstones' length and width in axial contrast-enhanced computed tomography (CT) images. X-tile software was utilized to calculate the optimal cutoff values of these parameters for evaluating survival and hepatic decompensation events in the cirrhosis group. Their associations with survival were explored by Cox regression analyses and Kaplan-Meier curve analyses. Their associations with hepatic decompensation events were evaluated by competing risk analyses and Nelson-Aalen cumulative risk curve analyses where death was a competing event.

Results

Cirrhotic patients with gallbladder length < 72 mm had a significantly higher cumulative survival rate than those with a length of ≥ 72 mm (P = 0.049 by log-rank test), but gallbladder width, gallbladder wall thickness, presence of gallstones, and gallstones' length and width were not significantly associated with survival (P = 0.10, P = 0.14, P = 0.97, P = 0.73, and P = 0.73 by log-rank tests, respectively). Cirrhotic patients with gallbladder wall thickness < 3.4 mm had a significantly lower cumulative rate of hepatic decompensation events than those with a wall thickness of ≥ 3.4 mm (P = 0.02 by Gray's test), but gallbladder length and width, presence of gallstones, and gallstones' length and width were not significantly associated with hepatic decompensation events (P = 0.15, P = 0.15, P = 0.54, P = 0.76, and P = 0.54 by Gray's tests, respectively).

Conclusion

Changes in gallbladder length and gallbladder wall thickness, rather than gallstone parameters, may be in parallel with the long-term outcomes of cirrhotic patients.

Short-term exposure of dairy cows to pyrrolizidine alkaloids from tansy ragwort (Jacobaea vulgaris Gaertn.): effects on organs and indicators of energy metabolism

Preserved feed from meadows contaminated with ragwort (Jacobaea vulgaris, Gaertn.) may expose livestock to pyrrolizidine alkaloids (PA). Dairy cows are considered to be very susceptible animals and a PA ingestion can lead to liver and further organ damages and even death. Due to the lack of data, the present study aimed to evaluate critical PA doses based on organ effects, with a special focus on liver lesions and on indicators of energy metabolism. Therefore, 16 dairy cows (n = 4 per group) were exposed to increasing PA doses (group: CONMolasses: <0.001 mg PA/kg body weight (BW)/day (d); PA1: 0.47 mg PA/kg BW/d; PA2: 0.95 mg PA/kg BW/d; PA3: 1.91 mg PA/kg BW/d) for 28 days. Constant dosing was ensured by a defined PA extract administered orally once daily. Histological examinations of the livers showed infiltration by immune cells, higher proportions of apoptotic cells and enlargement of hepatocyte nuclei in the highest exposed group. In addition, bile volume increased with PA dose, which may indicate a cholestasis. Despite the signs of incipient liver damage, liver lipid content and clinical chemical parameters related to energy metabolism, such as glucose, non-esterified fatty acids and βhydroxybutyrate, remained unaffected. Fat depot masses were also not significantly altered over time, suggesting that PA exposure did not induce a wasting syndrome. The liver showed slight microscopic changes already at a dosage of 0.95 mg PA/kg BW/d. However, the short-term metabolic indicators of energy status, lipolysis and ketogenesis, glucose, NEFA and BHB, as well as changes in fat depot, which serves as a longer-term indicator of lipolysis, remained unaffected in all treatment groups in the chosen scenario. These findings suggest that despite histopathological and clinical-chemical evidence of PA-associated hepatocellular lesions, liver function was not compromised.

The bile-gut axis and metabolic consequences of cholecystectomy

Cholelithiasis and cholecystitis affect individuals of all ages and are often treated by surgical removal of the gallbladder (cholecystectomy), which is considered a safe, low-risk procedure. Nevertheless, recent findings show that bile and its regulated storage and excretion may have important metabolic effects and that cholecystectomy is associated with several metabolic diseases postoperatively. Bile acids have long been known as emulsifiers essential to the assimilation of lipids and absorption of lipid-soluble vitamins, but more recently, they have also been reported to act as metabolic signaling agents. The nuclear receptor, farnesoid X receptor (FXR), and the G protein-coupled membrane receptor, Takeda G protein-coupled receptor 5 (TGR5), are specific to bile acids. Through activation of these receptors, bile acids control numerous metabolic functions. Cholecystectomy affects the storage and excretion of bile acids, which in turn may influence the activation of FXR and TGR5 and their effects on metabolism including processes leading to metabolic conditions such as metabolic dysfunction-associated steatotic liver disease and metabolic syndrome. Here, with the aim of elucidating mechanisms behind cholecystectomy-associated dysmetabolism, we review studies potentially linking cholecystectomy and bile acid-mediated metabolic effects and discuss possible pathophysiological mechanisms behind cholecystectomy-associated dysmetabolism.

Colesevelam has no acute effect on postprandial GLP-1 levels but abolishes gallbladder refilling

OBJECTIVE

Colesevelam, a bile acid sequestrant approved for the treatment of hypercholesterolaemia, improves glycaemic control in type 2 diabetes. We hypothesised that single-dose colesevelam increases postprandial GLP-1 secretion, thus, reducing postprandial glucose excursions in individuals with type 2 diabetes. Further, we explored the effects of single-dose colesevelam on ultrasonography-assessed postprandial gallbladder motility, paracetamol absorption (proxy for gastric emptying), and circulating factors known to affect gallbladder motility.

METHODS

In a randomised, double-blind, placebo-controlled crossover study, 12 individuals with type 2 diabetes (mean ± SD: age 61 ± 8.8 years; body mass index 29.8 ± 3.0 kg/m2) were subjected to 4 mixed meal tests on separate days; 2 with orally administered colesevelam (3.75 g) and 2 with placebo, with intravenous infusion of the GLP-1 receptor antagonist exendin(9-39)NH2 or saline.

RESULTS

Single-dose colesevelam had no effect on postprandial concentrations of glucose (P = .786), C-peptide (P = .440), or GLP-1 (P = .729), and exendin(9-39)NH2 administration revealed no GLP-1-mediated effects of colesevelam. Colesevelam did not affect gallbladder emptying but abolished gallbladder refilling (P = .001), increased postprandial cholecystokinin (CCK) secretion (P = .010), and decreased postprandial serum concentrations of fibroblast growth factor 19 (FGF19) (P = .035) and bile acids (P = .043).

CONCLUSION

Single-dose colesevelam had no effect on postprandial GLP-1 responses or glucose tolerance but disrupted postprandial gallbladder refilling by increasing CCK secretion and reducing circulating concentrations of FGF19 and bile acids. These findings leave the antidiabetic actions of colesevelam unresolved but provide mechanistic insights into its effect on gallbladder motility.

Resistance to Cholesterol Gallstone Disease: Hepatic Cholesterol Metabolism

Cholesterol gallstone disease (CGD) is one of the most common digestive diseases, and it is closely associated with hepatic cholesterol metabolism. Cholesterol gallstones may be caused by abnormal hepatic cholesterol metabolism, such as excessive cholesterol biosynthesis within the liver, interfering with the uptake or export of cholesterol in the liver, and abnormal hepatic cholesterol esterification. In this review, we begin with a brief overview of the clinical diagnosis and treatment of gallstone disease (GSD). Then, we briefly describe the major processes of hepatic cholesterol metabolism and summarize the key molecular expression changes of hepatic cholesterol metabolism in patients with gallstones. We review and analyze the recent advances in elucidating the relationships between these key molecules and CGD, and some targets significantly impacting on CGD via hepatic cholesterol metabolism are also listed. We also provide a significant discussion on the relationship between CGD and nonalcoholic fatty liver disease (NAFLD). Finally, the new discoveries of some therapeutic strategies associated with hepatic cholesterol metabolism to prevent and treat CGD are summarized.

Advances in the management of gallbladder polyps: establishment of predictive models and the rise of gallbladder-preserving polypectomy procedures

Gallbladder polyps are a common biliary tract disease whose treatment options have yet to be fully established. The indication of "polyps ≥ 10 mm in diameter" for cholecystectomy increases the possibility of gallbladder excision due to benign polyps. Compared to enumeration of risk factors in clinical guidelines, predictive models based on statistical methods and artificial intelligence provide a more intuitive representation of the malignancy degree of gallbladder polyps. Minimally invasive gallbladder-preserving polypectomy procedures, as a combination of checking and therapeutic approaches that allow for eradication of lesions and preservation of a functional gallbladder at the same time, have been shown to maximize the benefits to patients with benign polyps. Despite the reported good outcomes of predictive models and gallbladder-preserving polypectomy procedures, the studies were associated with various limitations, including small sample sizes, insufficient data types, and unknown long-term efficacy, thereby enhancing the need for multicenter and large-scale clinical studies. In conclusion, the emergence of predictive models and minimally invasive gallbladder-preserving polypectomy procedures has signaled an ever increasing attention to the role of the gallbladder and clinical management of gallbladder polyps.

Ultrasound-guided percutaneous microwave ablation of gallbladder polyps: A case report

RATIONALE

Gallbladder polyps are a general term for localized lesions in which the gallbladder wall protrudes into the gallbladder cavity, and benign lesions are common. Although current guidelines recommend cholecystectomy for gallbladder polyps ≥ 10 mm in size, the probability of finding cancer in postoperative pathological specimens is low. We should avoid unnecessary cholecystectomy and treat polyps with gallbladder preservation. Microwave ablation is safe and effective for the treatment of solid lesions, and can inactivates polyps while preserving gallbladder. Hence, we report a case of ultrasound-guided percutaneous microwave ablation of gallbladder polyps.

PATIENT CONCERNS

A 72-year-old female patient had previously diagnosed a gallbladder polyp, but it was not taken seriously. Recently, the patient had occasional right upper abdominal discomfort and a desire to preserve gallbladder.

DIAGNOSES

Ultrasound showed a medium hyperechoic papillary protrusion in the gallbladder without echo behind, and the changed position did not move. Contrast-enhanced ultrasound (CEUS) showed no malignant signs. The diagnosis was a gallbladder polyp.

INTERVENTIONS

The bile is drained and the drainage tube is fixed under real-time ultrasound guidance, then the gallbladder cavity is flushed and filled. Saline was injected between the serous and mucosal layers of the gallbladder to form an "edema band" to protect the gallbladder wall. Then, ultrasound-guided biopsy of gallbladder polyps was performed and sent for histological examination. Finally, the microwave needle was inserted into the target area under real-time ultrasonic guidance, and ablation was performed for 3 minutes (20 W). Postoperative CEUS: No significant enhancement was observed in the lesion.

OUTCOMES

Within 6 months of follow-up, the patient's gallbladder systolic function was normal, and there was no discomfort and no recurrence. The lesion reduction rate reached 100% at 1 week after surgery.

LESSONS

Ultrasound guided percutaneous microwave ablation of gallbladder polyps not only preserves the gallbladder but also inactivates the polyps without affecting the systolic function of the gallbladder, which provides a new idea for the treatment of gallbladder polyps.

Alteration of the fecal microbiome in patients with cholecystectomy: potential relationship with postcholecystectomy diarrhea - before and after study

BACKGROUND

Bile acid (BA) is a crucial determinant of the gut microbiome, and cholecystectomy can alter the physiology of BA. Physiological changes in BA resulting from cholecystectomy can also influence the gut microbiome. We aimed to identify the specific taxa associated with perioperative symptoms, including postcholecystectomy diarrhea (PCD), and to evaluate the effect of cholecystectomy on the microbiome by investigating the fecal microbiome of patients with gallstones.

METHODS

We analyzed the fecal samples of 39 patients with gallstones (GS group) and 26 healthy controls (HC group) to evaluate their gut microbiome. We also collected fecal samples from GS group 3 months postcholecystectomy. Symptoms of patients were evaluated before and after cholecystectomy. Further, 16S ribosomal RNA amplification and sequencing were performed to determine the metagenomic profile of fecal samples.

RESULTS

The microbiome composition of GS differed from that of HC; however, the alpha diversity was not different. No significant microbiome alterations were observed before and after cholecystectomy. Moreover, GS group showed a significantly lower Firmicutes to Bacteroidetes ratio before and after cholecystectomy than the HC group (6.2, P< 0.05). The inter-microbiome relationship was lower in GS than in HC and tended to recover 3 months after surgery. Furthermore, ~28.1% ( n =9) of patients developed PCD after surgery. The most prominent species among PCD (+) patients was Phocaeicola vulgatus. Compared with the preoperative state, Sutterellaceae , Phocaeicola , and Bacteroidals were the most dominant taxa among PCD (+) patients.

CONCLUSION

GS group showed a different microbiome from that of HC; however, their microbiomes were not different 3 months after cholecystectomy. Our data revealed taxa-associated PCD, highlighting the possibility of symptom relief by restoring the gut microbiome.

Piezo1 in Digestive System Function and Dysfunction

Piezo1, a non-selective cation channel directly activated by mechanical forces, is widely expressed in the digestive system and participates in biological functions physiologically and pathologically. In this review, we summarized the latest insights on Piezo1's cellular effect across the entire digestive system, and discussed the role of Piezo1 in various aspects including ingestion and digestion, material metabolism, enteric nervous system, intestinal barrier, and inflammatory response within digestive system. The goal of this comprehensive review is to provide a solid foundation for future research about Piezo1 in digestive system physiologically and pathologically.

Does postcholecystectomy increase the risk of colorectal cancer?

With the increasing number of cholecystectomy and the high proportion of colorectal cancer in malignant tumors, the question of whether cholecystectomy is a risk factor for colorectal disease has been widely concerned. After reviewing the literature at home and abroad, the authors will summarize the research progress of the correlation between the occurrence of colorectal tumors after cholecystectomy, in order to provide help for the prevention and treatment of colorectal tumors.

Glutaredoxin 1 regulates cholesterol metabolism and gallstone formation by influencing protein S-glutathionylation

OBJECTIVE

Cholesterol gallstone disease (CGD) is closely related to cholesterol metabolic disorder. Glutaredoxin-1 (Glrx1) and Glrx1-related protein S-glutathionylation are increasingly being observed to drive various physiological and pathological processes, especially in metabolic diseases such as diabetes, obesity and fatty liver. However, Glrx1 has been minimally explored in cholesterol metabolism and gallstone disease.

METHODS

We first investigated whether Glrx1 plays a role in gallstone formation in lithogenic diet-fed mice using immunoblotting and quantitative real-time PCR. Then a whole-body Glrx1-deficient (Glrx1^-/-) mice and hepatic-specific Glrx1-overexpressing (AAV8-TBG-Glrx1) mice were generated, in which we analyzed the effects of Glrx1 on lipid metabolism upon LGD feeding. Quantitative proteomic analysis and immunoprecipitation (IP) of glutathionylated proteins were performed.

RESULTS

We found that protein S-glutathionylation was markedly decreased and the deglutathionylating enzyme Glrx1 was greatly increased in the liver of lithogenic diet-fed mice. Glrx1^-/- mice were protected from gallstone disease induced by a lithogenic diet because their biliary cholesterol and cholesterol saturation index (CSI) were reduced. Conversely, AAV8-TBG-Glrx1 mice showed greater gallstone progression with increased cholesterol secretion and CSI. Further studies showed that Glrx1-overexpressing greatly induced bile acid levels and/or composition to increase intestinal cholesterol absorption by upregulating Cyp8b1. In addition, liquid chromatography-mass spectrometry and IP analysis revealed that Glrx1 also affected the function of asialoglycoprotein receptor 1 (ASGR1) by mediating its deglutathionylation, thereby altering the expression of LXRα and controlling cholesterol secretion.

CONCLUSION

Our findings present novel roles of Glrx1 and Glrx1-regulated protein S-glutathionylation in gallstone formation through the targeting of cholesterol metabolism. Our data advises Glrx1 significantly increased gallstone formation by simultaneously increase bile-acid-dependent cholesterol absorption and ASGR1- LXRα-dependent cholesterol efflux. Our work suggests the potential effects of inhibiting Glrx1 activity to treat cholelithiasis.

Rare or Overlooked Cases of Acute Acalculous Cholecystitis in Young Patients with Central Nervous System Lesion

This case series presents two cases of acute acalculous cholecystitis (AAC)-a rare condition-in young women with central nervous system (CNS) lesions. Both patients had significant neurologic deficits and no well-known risk factors or presence of comorbidities (such as diabetes or a history of cardiovascular or cerebrovascular disease). Early diagnosis is important in cases of AAC owing to its high mortality rate; however, due to neurological deficits in our cases, accurate medical and physical examinations were limited, thereby leading to a delay in the diagnosis. The first case was of a 33-year-old woman with multiple fractures and hypovolemic shock due to a traumatic accident; she was diagnosed with hypoxic brain injury. The second case was of a 32-year-old woman with bipolar disorder and early-onset cerebellar ataxia who developed symptoms of impaired cognition and psychosis; she was later diagnosed with autoimmune encephalopathy. In the first case, the duration between symptom onset and diagnosis was 1 day, but in the second case, it was 4 days from diagnosis based on the occurrence of high fever. We emphasize that if a young woman presents with high fever, the possibility of AAC should be considered, particularly if a CNS lesion is present because it may pose difficulty in the evaluation of typical symptoms of AAC. Careful attention is thus required in such cases.

Impact of cholecystectomy on acute coronary syndrome according to metabolic condition: a nationwide population-based cohort study

Gallbladder stones (GS) is associated with an increased risk of cardiovascular disease. However, the relationship between cholecystectomy for GS and acute coronary syndrome (ACS) is unknown. We investigated the ACS risk in patients with GS and its association with cholecystectomy. Data from the Korean National Health Insurance Service-National Sample Cohort from 2002 to 2013 was extracted. Overall, 64,370 individuals were selected through a 1:3 propensity score matching. Patients were stratified into two groups for comparison: the gallstone group, GS patients with or without cholecystectomy; and the control group, patients without GS or cholecystectomy. The gallstone group exhibited a higher risk of ACS than the control group (hazard ratio [HR], 1.30; 95% confidence interval [CI] 1.15-1.47; P < 0.0001). In the gallstone group, individuals without cholecystectomy had a higher risk of ACS development (HR: 1.35, 95% CI 1.17-1.55, P < 0.0001). Patients with GS with diabetes, hypertension, or dyslipidemia, had a higher risk of developing ACS than GS patients without the metabolic diseases (HR: 1.29, P < 0.001). The risk did not significantly differ after cholecystectomy compared to those without GS (HR: 1.15, P = 0.1924), but without cholecystectomy, the risk of ACS development was significantly higher than control group (1.30, 95% CI 1.13-1.50, P = 0.0004). Among patients without above metabolic disorders, cholecystectomy was still associated with increased ACS risk in the gallstone group (HR: 2.93, 95% CI 1.27-6.76, P = 0.0116). GS increased the risk of ACS. The effect of cholecystectomy on ACS risk differs according to the presence or absence of metabolic disorders. Thus, the decision to perform cholecystectomy for GS should consider both the ACS risk and the underlying disorders.

Cholecystectomy and risk of liver disease: a systematic review and meta-analysis of 27 million individuals

BACKGROUND

There is still a lack of knowledge on the association between cholecystectomy and liver disease. This study was conducted to summarize the available evidence on the association of cholecystectomy with liver disease and quantify the magnitude of the risk of liver disease after cholecystectomy.

METHODS

PubMed, Embase, Web of Science, and Cochrane Library were searched systematically from database inception to January 2023 to identify eligible studies that evaluated the association between cholecystectomy and the risk of liver disease. Meta-analysis was conducted to obtain a summary odds ratio (OR) and 95% confidence interval (CI) using a random-effects model.

RESULTS

We identified 20 studies with a total of 27 320 709 individuals and 282 670 liver disease cases. Cholecystectomy was associated with an increased risk of liver disease (OR: 1.63, 95% CI: 1.34-1.98). In particular, cholecystectomy was found to be significantly associated with a 54% increased risk of nonalcoholic fatty liver disease (OR: 1.54, 95% CI: 1.18-2.01), a 173% increased risk of cirrhosis (OR: 2.73, 95% CI: 1.81-4.12), and a 46% increased risk of primary liver cancer (OR: 1.46, 95% CI: 1.18-1.82).

CONCLUSIONS

There is an association between cholecystectomy and the risk of liver disease. Our results suggest that strict surgical indications should be implemented to reduce unnecessary cholecystectomy. Additionally, the routine assessment of liver disease is necessary for patients with a history of cholecystectomy. More prospective large-sample studies are required for better estimates of the risk.

Protective potential of the gallbladder in primary sclerosing cholangitis

Background & Aims

Gallbladder enlargement is common in patients with primary sclerosing cholangitis (PSC). The gallbladder may confer hepatoprotection against bile acid overload, through the sequestration and cholecystohepatic shunt of bile acids. The aim of this study was to assess the potential impact of the gallbladder on disease features and bile acid homeostasis in PSC.

Methods

Patients with PSC from a single tertiary center who underwent liver MRI with three-dimensional cholangiography and concomitant analyses of serum bile acids were included. Gallbladder volume was measured by MRI and a cut-off of 50 ml was used to define gallbladder enlargement. Bile acid profiles and PSC severity, as assessed by blood tests and MRI features, were compared among patients according to gallbladder size (enlarged vs. normal-sized) or presence (removed vs. conserved). The impact of cholecystectomy was also assessed in the Abcb4 knockout mouse model of PSC.

Results

Sixty-one patients with PSC, all treated with ursodeoxycholic acid (UDCA), were included. The gallbladder was enlarged in 30 patients, whereas 11 patients had been previously cholecystectomized. Patients with enlarged gallbladders had significantly lower alkaline phosphatase, a lower tauro-vs. glycoconjugate ratio and a higher UDCA vs. total bile acid ratio compared to those with normal-sized gallbladders. In addition, gallbladder volume negatively correlated with the hydrophobicity index of bile acids. Cholecystectomized patients displayed significantly higher aspartate aminotransferase and more severe bile duct strictures and dilatations compared to those with conserved gallbladder. In the Abcb4 knockout mice, cholecystectomy caused an increase in hepatic bile acid content and in circulating secondary bile acids, and an aggravation in cholangitis, inflammation and liver fibrosis.

Conclusion

Altogether, our findings indicate that the gallbladder fulfills protective functions in PSC.

Impact and implications

In patients with primary sclerosing cholangitis (PSC), gallbladder status impacts on bile acid homeostasis and disease features. We found evidence of lessened bile acid toxicity in patients with PSC and enlarged gallbladders and of increased disease severity in those who were previously cholecystectomized. In the Abcb4 knockout mouse model of PSC, cholecystectomy causes an aggravation of cholangitis and liver fibrosis. Overall, our results suggest that the gallbladder plays a protective role in PSC.

The analysis of gut microbiota in patients with bile acid diarrhoea treated with colesevelam

Introduction

Bile acid diarrhoea (BAD) is a common disorder that results from an increased loss of primary bile acids and can result in a change in microbiome. The aims of this study were to characterise the microbiome in different cohorts of patients with BAD and to determine if treatment with a bile acid sequestrant, colesevelam, can alter the microbiome and improve microbial diversity.

Materials and methods

Patients with symptoms of diarrhoea underwent 75-selenium homocholic acid (75SeHCAT) testing and were categorised into four cohorts: idiopathic BAD, post-cholecystectomy BAD, post-operative Crohn’s disease BAD and 75SeHCAT negative control group. Patients with a positive 75SeHCAT (&lt;15%) were given a trial of treatment with colesevelam. Stool samples were collected pre-treatment, 4-weeks, 8-weeks and 6–12 months post-treatment. Faecal 16S ribosomal RNA gene analysis was undertaken.

Results

A total of 257 samples were analysed from 134 patients. α-diversity was significantly reduced in patients with BAD and more specifically, in the idiopathic BAD cohort and in patients with severe disease (SeHCAT &lt;5%); p &lt; 0.05. Colesevelam did not alter bacterial α/β-diversity but patients who clinically responded to treatment had a significantly greater abundance of Fusobacteria and Ruminococcus, both of which aid in the conversion of primary to secondary bile acids.

Conclusion

This is the first study to examine treatment effects on the microbiome in BAD, which demonstrated a possible association with colesevelam on the microbiome through bile acid modulation in clinical responders. Larger studies are now needed to establish a causal relationship with colesevelam and the inter-crosstalk between bile acids and the microbiome.

Circulating Bile Acids as Biomarkers for Disease Diagnosis and Prevention

CONTEXT

Bile acids (BAs) are pivotal signaling molecules that regulate energy metabolism and inflammation. Recent epidemiological studies have reported specific alterations in circulating BA profiles in certain disease states, including obesity, type 2 diabetes mellitus (T2DM), nonalcoholic fatty liver disease (NAFLD), and Alzheimer disease (AD). In the past decade, breakthroughs have been made regarding the translation of BA profiling into clinical use for disease prediction. In this review, we summarize and synthesize recent data on variation in circulating BA profiles in patients with various diseases to evaluate the value of these biomarkers in human plasma for early diagnosis.

EVIDENCE ACQUISITION

This review is based on a collection of primary and review literature gathered from a PubMed search for BAs, obesity, T2DM, insulin resistance (IR), NAFLD, hepatocellular carcinoma (HCC), cholangiocarcinoma (CCA), colon cancer, and AD, among other keywords.

EVIDENCE SYNTHESIS

Individuals with obesity, T2DM, HCC, CCA, or AD showed specific alterations in circulating BA profiles. These alterations may have existed long before the initial diagnosis of these diseases. The intricate relationship between obesity, IR, and NAFLD complicates the establishment of clear and independent associations between BA profiles and nonalcoholic steatohepatitis. Alterations in the levels of total BAs and several BA species were seen across the entire spectrum of NAFLD, demonstrating significant increases with the worsening of histological features.

CONCLUSIONS

Aberrant circulating BA profiles are an early event in the onset and progression of obesity, T2DM, HCC, and AD. The pleiotropic effects of BAs explain these broad connections. Circulating BA profiles could provide a basis for the development of biomarkers for the diagnosis and prevention of a wide range of diseases.

The clinical effect of a strategy called transcystic gallbladder-preserving cholecystolithotomy based on endoscopic retrograde cholangiopancreatography for cholecystolithiasis: A retrospective study from a single center

Background

Choledocholithiasis complicated with cholecystolithiasis is a common disease. This study explores a novel strategy, called ERCP-based transcystic gallbladder-preserving cholecystolithotomy, for the simultaneous removal of common bile duct stones and gallbladder stones.

Methods

From December 2018 to June 2021, all patients with cholecystolithiasis and common bile duct stones who met the criteria for gallbladder preservation in our hospital were included in the study and prospectively followed up.

Results

We included 48 patients, including 20 patients with acute biliary pancreatitis. All patients successfully underwent ERCP to remove common bile duct stones. One patient had gallbladder perforation during gallbladder-preserving cholecystolithotomy. The guide wire successfully entered the gallbladder, and the transpapillary gallbladder metal-covered stent was successfully placed in 44 patients. The technical success rate was 91.67% (44/48). All stones were removed in 34 patients, for a clinical success rate of 77.27% (34/44). The total postoperative complication rate was 6.25% (3/48), with 2 cases of pancreatitis (4.17%) and 1 case of cholangitis (2.08%). Three patients were lost to follow-up. Among the 31 patients who were followed up for a mean of 27 months (6-40), 5 patients (16.13%) experienced gallstone recurrence. The recurrence rates at 12 months, 18 months, 24 months, 30 months and 36 months were 0%, 3.23%, 6.45%, 12.9%, and 16.13%, respectively.

Conclusion

For patients with cholecystolithiasis and common bile duct stones, ERCP-based transcystic gallbladder-preserving cholecystolithotomy without gallbladder incision can preserve gallbladder structure, and this procedure is safe and feasible for the protection of gallbladder function.Clinical trial registration: The study was registered in the Chinese Clinical Trial Registry, and the registry number is ChiCTR1900028006.

Effect of nicotine on cholesterol gallstone formation in C57BL/6J mice fed on a lithogenic diet

Gallstones are diseases of the biliary system caused by cholesterol supersaturation and/or deficiency in bile salts in bile. Early studies have shown that symptomatic gallstones are primarily a disease of non-smokers, raising the possibility that nicotine can prevent gallstone formation. The present study investigated the effect of nicotine on the formation of cholesterol gallstone in C57BL/6J mice. C57BL/6J mice (eight-weeks-old) were fed a normal or lithogenic diet (basic feed 82.45%, fat 15.8%, cholesterol 1.25% and sodium cholate 0.5%) and divided into five groups: normal diet (ND); ND + high dose nicotine (H); lithogenic diet (LD); LD + low dose nicotine (L) and LD + nicotine (H). They were treated with or without nicotine injection for 10 weeks. Nicotine treatment did not change the rate of cholesterol gallstone formation. There was no difference in TNFα, IL-1β and IL-6 among the five groups. The LD group showed the highest cholesterol levels and there was significant suppression of the total cholesterol, low-density lipoprotein-cholesterol and total bile acid levels in the serum of the nicotine-treated mice. Quantitative PCR showed nicotine altered few bile acid metabolism-related genes expression in liver tissue and significantly altered cholesterol-metabolism genes in gallbladder tissue. Hematoxylin and eosin staining and western blotting showed that protein levels of farnesoid X receptor (FXR) and megalin in the gallbladder increased in the lithogenic-diet mice, which was significantly suppressed in the nicotine-treated mice. In vitro studies using gallbladder epithelial cells showed that chenodeoxycholic acids increased megalin expression, which could be attenuated by nicotine. Nicotine could regulate bile acid metabolism via the FXR-megalin/cubilin pathways, which potentially contribute to cholesterol nucleation and subsequent gallstone formation.

Clinical and Molecular Insights into Gastrointestinal Dysfunction in Myotonic Dystrophy Types 1 & 2

Myotonic dystrophy (DM) is a highly variable, multisystemic disorder that clinically affects one in 8000 individuals. While research has predominantly focused on the symptoms and pathological mechanisms affecting striated muscle and brain, DM patient surveys have identified a high prevalence for gastrointestinal (GI) symptoms amongst affected individuals. Clinical studies have identified chronic and progressive dysfunction of the esophagus, stomach, liver and gallbladder, small and large intestine, and rectum and anal sphincters. Despite the high incidence of GI dysmotility in DM, little is known regarding the pathological mechanisms leading to GI dysfunction. In this review, we summarize results from clinical and molecular analyses of GI dysfunction in both genetic forms of DM, DM type 1 (DM1) and DM type 2 (DM2). Based on current knowledge of DM primary pathological mechanisms in other affected tissues and GI tissue studies, we suggest that misregulation of alternative splicing in smooth muscle resulting from the dysregulation of RNA binding proteins muscleblind-like and CUGBP-elav-like is likely to contribute to GI dysfunction in DM. We propose that a combinatorial approach using clinical and molecular analysis of DM GI tissues and model organisms that recapitulate DM GI manifestations will provide important insight into defects impacting DM GI motility.

Updates in interaction of gastroesophageal reflux disease and extragastroesophageal digestive diseases

INTRODUCTION

Gastroesophageal reflux disease (GERD) is one of the common chronic diseases with prevalence increasing in the last decades. Because of its prevalence and chronicity, GERD affects the quality of life and increases health-care costs. Gastroesophageal diseases leading to GERD have been thoroughly studied, while extragastroesophageal digestive diseases (EGEDDs) may coexist with GERD and affect the occurrence and persistence of GERD symptoms and therapeutic effect.

AREAS COVERED

In this review, we aim to summarize the EGEDDs correlated with GERD and explore the potential mechanisms of this interaction.

EXPERT OPINION

Individuals with troublesome GERD symptoms may have some common gastroesophageal etiologies, but EGEDDs may also overlap and impact on the progression of GERD, which are often ignored in clinic. The lesions in the small intestine, colon, and hepatobiliary tract as well as functional bowel disorders had positive or negative associations with GERD through potential mechanisms. These diseases aggravate GERD symptoms, increase the esophageal acid burden, cause esophageal hypersensitivity, and finally affect the response to therapy in GERD patients. Therefore, it is necessary to clear the interaction between GERD and EGEDDs and their mechanisms.

Establishment and characterization of an immortalized epithelial cell line from human gallbladder

Background

Although a plethora of studies have employed multiple gallbladder cancer (GBC) cell lines, it is surprisingly noted that there is still lack of a normal gallbladder epithelial cell line as a normal counterpart, thus impeding substantially the progress of mechanistic studies on the transformation of normal epithelial cells to cancer. Here, we created a normal gallbladder epithelial cell line named L-2F7 from human gallbladder tissue.

Methods

Gallbladder tissues from a diagnosed cholecystitis female patient were collected, and epithelial cells were enriched by magnetic cell sorting. Then, the cells were immortalized by co-introduction of human telomerase reverse transcriptase (hTERT) and Simian virus 40 large T antigen (LT-SV40) via a lentivirus infection system. After clonal selection and isolation, L-2F7 cells were tested for epithelial markers CK7, CK19, CK20, and CD326, genomic feature, cell proliferation, and migration using Western blot, immunofluorescence, whole genome sequencing, karyotyping, and RNA sequencing. L-2F7 cells were also transplanted to Nude (nu/nu) mice to determine tumorigenicity.

Results

We successfully identified one single-cell clone named L-2F7 which highly expressed epithelial markers CD326, CK7, CK19, and CK20. This cell line proliferated with a doubling time of 23 h and the epithelial morphology sustained over 30 passages following immortalization. Transient gene transduction of L-2F7 cells led to expression of exogenous GFP and FLAG protein. L-2F7 cells exhibited both distinct non-synonymous mutations from those of gallbladder cancer tissues and differential non-cancerous gene expression patterns similar to normal tissue. Although they displayed unexpected mobility, L-2F7 cells still lacked the ability to develop tumors.

Conclusion

We developed a non-cancerous gallbladder epithelial cell line, offering a valuable system for the study of gallbladder cancer and other gallbladder-related disorders.

Cholecystectomy promotes the development of colorectal cancer by the alternation of bile acid metabolism and the gut microbiota

The incidence and mortality of colorectal cancer (CRC) have been markedly increasing worldwide, causing a tremendous burden to the healthcare system. Therefore, it is crucial to investigate the risk factors and pathogenesis of CRC. Cholecystectomy is a gold standard procedure for treating symptomatic cholelithiasis and gallstone diseases. The rhythm of bile acids entering the intestine is altered after cholecystectomy, which leads to metabolic disorders. Nonetheless, emerging evidence suggests that cholecystectomy might be associated with the development of CRC. It has been reported that alterations in bile acid metabolism and gut microbiota are the two main reasons. However, the potential mechanisms still need to be elucidated. In this review, we mainly discussed how bile acid metabolism, gut microbiota, and the interaction between the two factors influence the development of CRC. Subsequently, we summarized the underlying mechanisms of the alterations in bile acid metabolism after cholecystectomy including cellular level, molecular level, and signaling pathways. The potential mechanisms of the alterations on gut microbiota contain an imbalance of bile acid metabolism, cellular immune abnormality, acid-base imbalance, activation of cancer-related pathways, and induction of toxin, inflammation, and oxidative stress.

Bile Reflux Gastritis: Insights into Pathogenesis, Relevant Factors, Carcinomatous Risk, Diagnosis, and Management

Bile reflux gastritis (BRG), a kind of gastrointestinal disorder in clinical practice, is characterized by regurgitation and inflammation. However, lack of guidelines leads to simple cognition and even ignorance of this disease for clinicians. Primarily, making the pathogenesis of BRG clear contributes to a correct and general understanding of this disease for physicians. Next, although recently there has been an increasing awareness among researchers in terms of the relevant factors for BRG, further studies involving large samples are still required to certify the relationship between them explicitly. Besides, researches have established that BRG is closely associated with the development of precancerous lesions and gastric cancer. Till now, there is still no golden standard for diagnosis of BRG. Nevertheless, advances in techniques, especially extensive applications of endoscopy and chemical analysis of reflux contents, have improved our ability to identify the occurrence of this disease as well as distinguishing physiological reflux from pathological reflux. Finally, it is fortunate for patients that more and more importance has been attached to the treatment of BRG. From lifestyle modification to drug therapy to surgery, all of them with the view of realizing symptomatic relief are employed for patients with BRG. In this review, we briefly evaluate this disorder based on the best available evidence, offering an overview of its complicated pathogenesis, diverse relevant factors, potential carcinomatous risk, modern diagnostic investigations, and effective therapeutic plans.

A new operation for gallstones: Choledochoscopic gallbladder-preserving cholecystolithotomy, a retrospective study of 3,511 cases

BACKGROUND

Due to the influence of traditional Chinese culture, many cholelithiasis patients refuse to undergo cholecystectomy. This has prompted surgeons to consider a new treatment option for gallstones, which preserves the gallbladder, termed as choledochoscopic gallbladder-preserving cholecystolithotomy. In this study, we reviewed the clinical outcomes of 23 years of single-center application of choledochoscopic gallbladder-preserving cholecystolithotomy.

METHODS

A total of 5,451 patients with chronic cholelithiasis were selected from 1992 to 2011 as per the inclusion criteria for the choledochoscopic gallbladder-preserving cholecystolithotomy study, and clinicopathological and follow-up data were collected from 4,340 patients who underwent successful choledochoscopic gallbladder-preserving cholecystolithotomy. The endpoints of the follow-up were recurrence of stones, loss to follow-up, patient death, removal of the gallbladder for other reasons, or end of follow-up in December 2015.

RESULTS

All 4,340 cases underwent choledochoscopic gallbladder-preserving cholecystolithotomy with a mean procedure time of 79.6 ± 35.4 minutes, among which 3,511 (80.9%) received at least 1 follow-up. The recurrence rate of gallstones gradually increased with increasing follow-up duration, with a recurrence rate of 0.83% within 1 year after surgery and a maximal cumulative recurrence rate of 7.94% at 23 years. The 5-year cumulative recurrence rate of gallstones in the age group ≤20 years was 16.80%, which was significantly higher than those of other age groups, and the 5-year recurrence rate in the single gallstone group was 2.87%, which was significantly lower than that in the multiple gallstone group. Age and number of gallstones were independent risk factors for gallstone recurrence after choledochoscopic gallbladder-preserving cholecystolithotomy.

CONCLUSION

The recurrence rate of gallstones after choledochoscopic gallbladder-preserving cholecystolithotomy is low, and most patients with recurrence are asymptomatic or have only mild symptoms. Age and number of gallstones were independent risk factors. Choledochoscopic gallbladder-preserving cholecystolithotomy is a safe and effective surgical option for gallstone removal in patients who do not wish to undergo cholecystectomy.

Targets of statins intervention in LDL-C metabolism: Gut microbiota

Increasing researches have considered gut microbiota as a new “metabolic organ,” which mediates the occurrence and development of metabolic diseases. In addition, the liver is an important organ of lipid metabolism, and abnormal lipid metabolism can cause the elevation of blood lipids. Among them, elevated low-density lipoprotein cholesterol (LDL-C) is related with ectopic lipid deposition and metabolic diseases, and statins are widely used to lower LDL-C. In recent years, the gut microbiota has been shown to mediate statins efficacy, both in animals and humans. The effect of statins on microbiota abundance has been deeply explored, and the pathways through which statins reduce the LDL-C levels by affecting the abundance of microbiota have gradually been explored. In this review, we discussed the interaction between gut microbiota and cholesterol metabolism, especially the cholesterol-lowering effect of statins mediated by gut microbiota, via AMPK-PPARγ-SREBP1C/2, FXR and PXR-related, and LPS-TLR4-Myd88 pathways, which may help to explain the individual differences in statins efficacy.

Anion Transport Across Human Gallbladder Organoids and Monolayers

Fluid and anion secretion are important functions of the biliary tract. It has been established that cAMP regulates Na⁺ absorption through NHE3. However, mechanisms of gallbladder anion transport are less defined. We created organoids and organoid-derived monolayers from human gallbladder tissue to measure organoid swelling and transepithelial electrophysiology. In our in vitro models, forskolin-stimulation caused organoid swelling and increased transepithelial anion transport. Full organoid swelling required Cl⁻while changes in short-circuit current were HCO₃⁻-dependent. Organoids and monolayers from an individual homozygous for the cystic fibrosis-causing ΔF508 CFTR mutation had no apical expression of CFTR and minimal changes in transepithelial current and conductance with forskolin treatment. However, organoid swelling remained intact. Dilution potential studies revealed that forskolin treatment increased the paracellular permeability to anions relative to cations. These data suggest a novel paracellular contribution to forskolin-stimulated fluid transport across the gallbladder epithelium.

Effects of Bile Acid Modulation by Dietary Fat, Cholecystectomy, and Bile Acid Sequestrant on Energy, Glucose, and Lipid Metabolism and Gut Microbiota in Mice

Bile acid metabolism, involved with the digestion and absorption of nutrients in the gut, is linked to the gut microbiota community, greatly impacting the host’s metabolism. We examined the hypothesis that the modulation of bile acid metabolism by dietary fat contents, gallbladder removal (GBX; cholecystectomy), and bile acid sequestrant (BAS; cholestyramine) treatment could alter energy, glucose, and lipid metabolism through the changes in the gut microbiota. Mice were randomly assigned to the following six groups: (1) Sham GBX surgery (Sham) + low fat/high carbohydrate diet (LFD), (2) Sham + high fat diet (HFD), (3) Sham + HFD + BAS, (4) GBX + LFD, (5) GBX + HFD, and (6) GBX + HFD + BAS. BAS groups received 2% cholestyramine. After an 8-week intervention, energy, glucose, and lipid metabolism, and the gut microbiota community were measured. HFD groups exhibited higher body weight gain than LFD, and GBX increased the weight gain comped to Sham groups regardless of BAS in HFD (p < 0.05). Homeostatic model assessment for insulin resistance (HOMA-IR) was higher in HFD than LFD, and GBX increased it regardless of BAS. Serum lipid profiles were worsened in GBX + HFD compared to Sham + LFD, whereas BAS alleviated them, except for serum HDL cholesterol. Hepatic tumor-necrosis-factor-α (TNF-α) mRNA expression and lipid peroxide contents increased with GBX and BAS treatment compared to Sham and no BAS treatment (p < 0.05). Hepatic mRNA expression of sterol regulatory element-binding transcription factor 1c (SREBP1c) and peroxisome proliferator-activated receptor gamma (PPAR-γ) exhibited the same trend as that of tumor necrosis factor-α (TNF-α). The α-diversity of gut bacteria decreased in GBX + HFD and increased in GBX + HFD + BAS. Akkermentia, Dehalobacterium, SMB53, and Megamonas were high in the Sham + LFD, and Veillonella and Streptococcus were rich in the Sham + HFD, while Oscillospira and Olsenella were high in Sham + HFD + BAS (p < 0.05). GBX + LFD increased Lactobacillus and Sutterella while GBX + HFD + BAS elevated Clostridium, Alistipes, Blautia, Eubacterium, and Coprobacillus (p < 0.05). In conclusion, the modulation of bile acid metabolism influences energy, glucose, and lipid metabolisms, and it might be linked to changes in the gut microbiota by bile acid metabolism modulation.

Bile Flow Dynamics in Patients with Cholelithiasis: An Evaluation with Cine-Dynamic Magnetic Resonance Cholangiopancreatography Using a Spatially Selective Inversion-Recovery Pulse

Background: A variety of pathophysiological changes in the biliary system occur in patients with cholelithiasis, but the changes in the bile flow dynamics in those patients remain unclear. The purpose of this study was to elucidate the changes in the bile flow dynamics in patients with cholelithiasis using cine-dynamic magnetic resonance cholangiopancreatography (MRCP) with a spatially selective inversion-recovery (IR) pulse. Methods: We retrospectively examined 25 patients with gallstones (gallstone group) and 69 patients without gallstones (non-gallstone group) who underwent abdominal MRI, including in- and opposed-phase T1-weighted images and cine-dynamic MRCP with a spatially selective IR pulse. The frequency and secretion grade of the antegrade and reverse flow of the bile on the cine dynamic MRCP images and the signal intensity ratio (SIR) of the gallbladder in the in- and opposed-phase T1-weighted images were evaluated. Results: The frequency and mean secretion grade of the antegrade bile flow were significantly higher in the gallstone group than in the non-gallstone group (p = 0.011 and p = 0.003), while no significant differences in those values of the reverse bile flow were found between the two groups. The SIR of the gallbladder in the T1-weighted gradient-echo in-phase images was significantly lower in the gallstone group than in the non-gallstone group (p = 0.004). Conclusions: Cine-dynamic MRCP with a spatially selective IR pulse can noninvasively visualize changes in the bile flow dynamics of patients with gallstones.

Cysteinyl leukotrienes and acetylcholine are biliary tuft cell cotransmitters

The gallbladder stores bile between meals and empties into the duodenum upon demand and is thereby exposed to the intestinal microbiome. This exposure raises the need for antimicrobial factors, among them, mucins produced by cholangiocytes, the dominant epithelial cell type in the gallbladder. The role of the much less frequent biliary tuft cells is still unknown. We here show that propionate, a major metabolite of intestinal bacteria, activates tuft cells via the short-chain free fatty acid receptor 2 and downstream signaling involving the cation channel transient receptor potential cation channel subfamily M member 5. This results in corelease of acetylcholine and cysteinyl leukotrienes from tuft cells and evokes synergistic paracrine effects upon the epithelium and the gallbladder smooth muscle, respectively. Acetylcholine triggers mucin release from cholangiocytes, an epithelial defense mechanism, through the muscarinic acetylcholine receptor M3. Cysteinyl leukotrienes cause gallbladder contraction through their cognate receptor CysLTR1, prompting emptying and closing. Our results establish gallbladder tuft cells as sensors of the microbial metabolite propionate, initiating dichotomous innate defense mechanisms through simultaneous release of acetylcholine and cysteinyl leukotrienes.

The role of the colonic microbiota and bile acids in colorectal cancer

PURPOSE OF REVIEW

Colorectal cancer (CRC) is the third most common cancer and the second most common cause of cancer-related deaths. Of the various established risk factors for this aggressive condition, diet is a notable modifiable risk factor. This review aims to summarize the mounting evidence to suggest the role of diet, the microbiota and their cross-talk in modulating an individual's risk of developing CRC.

RECENT FINDINGS

Specifically, the metabolism of bile acids and its symbiosis with the microbiota has gained weight given its basis on a high meat, high fat, and low fibre diet that is present in populations with the highest risk of CRC. Bacteria modify bile acids that escape enterohepatic circulation to increase the diversity of the human bile acid pool. The production of microbial bile acids contributes to this as well. Epidemiological studies have shown that changing the diet results in different levels and composition of bile acids, which has in turn modified the risk of CRC at a population level. Evidence to identify underlying mechanisms have tied into the microbiota-led digestions of various foods into fatty acids that feedback into bile acid physiology as well as modulation of endogenous receptors for bile acids.

SUMMARY

There is adequate evidence to support the role of microbiota in in the metabolism of bile acids, and how this relates to colorectal cancer. Further work is necessary to identify specific bacteriome involved and their underlying mechanistic pathways.

Disordered Gut Microbiota Correlates With Altered Fecal Bile Acid Metabolism and Post-cholecystectomy Diarrhea

Post-cholecystectomy diarrhea (PCD) is a common complication of gallbladder removal, and gut microbiota changes have been determined in PCD patients. Bile acid diarrhea (BAD) is supposed to be the main pathogenic factor for PCD due to the disrupted fecal bile acid metabolism in diarrheal patients. However, the profiling of bile acid metabolite alteration in PCD is unclear and whether changed gut microbiota and fecal bile acid metabolism are correlated is also underdetermined. The fecal bile acid metabolites from fecal samples were profiled by targeted UPLC/MS (ultra-high-performance liquid chromatography coupled with a triple-quadrupole mass spectrometer) and the composition of fecal bile acid metabolites in PCD patients was demonstrated to be distinct from those in Non-PCD and HC groups. In addition, the quantification of bile acid excretion in feces of diarrheal patients was significantly elevated. Furthermore, 16S rRNA sequencing results revealed that PCD patients had the lowest operational taxonomic units (OTU) and significant reduction in microbial richness and evenness. Bacterial composition was remarkably shifted in PCD patients, which mainly lay in dominated phyla Firmicutes and Bacteroidota. Besides, the co-abundance network among genus bacteria declined in PCD. Among the genera, Prevotella, Enterococcus, and Erysipelotrichaceae_UCG-003 were enriched, but Alistipes, Bacteroides, Ruminococcus, and Phascolarctobacterium were reduced. Moreover, these disease-linked genera were closely associated with several diarrheal phenotypes. Notably, changed bile acid metabolites exhibited strong correlations with gut microbiota as well. Conclusively, this study reveals associations between PCD-linked microbes and bile acid metabolites, which may synergistically correlate to postoperative diarrhea.

Free Drug Theory - No Longer Just a Hypothesis?

The Free Drug Hypothesis is a well-established concept within the scientific lexicon pervading many areas of Drug Discovery and Development, and yet it is poorly defined by virtue of many variations appearing in the literature. Clearly, unbound drug is in dynamic equilibrium with respect to absorption, distribution, metabolism, elimination, and indeed, interaction with the desired pharmacological target. Binding interactions be they specific (e.g. high affinity) or nonspecific (e.g. lower affinity/higher capacity) are governed by the same fundamental physicochemical tenets including Hill-Langmuir Isotherms, the Law of Mass Action and Drug Receptor Theory. With this in mind, it is time to recognise a more coherent version and consider it the Free Drug Theory and a hypothesis no longer. Today, we have the experimental and modelling capabilities, pharmacological knowledge, and an improved understanding of unbound drug distribution (e.g. Kp_uu) to raise the bar on our understanding and analysis of experimental data. The burden of proof should be to rule out mechanistic possibilities and/or experimental error before jumping to the conclusion that any observations contradict these fundamentals.

Risk Factors for Early Recurrence of Gallstones in Patients Undergoing Laparoscopy Combined With Choledochoscopic Lithotomy: A Single-Center Prospective Study

Objective: For patients with gallstones, laparoscopy combined with choledochoscopic lithotomy is a therapeutic surgical option for preservation rather than the removal of the gallbladder. However, postoperative recurrence of gallstones is a key concern for both patients and surgeons. This prospective study was performed to investigate the risk factors for early postoperative recurrence of gallstones.

Methods: The clinical data of 466 patients were collected. Each patient was followed up for up to 2 years. The first follow-up visit occurred 4 months after the operation, and a follow-up visit was carried out every 6 months thereafter. The main goal of each visit was to confirm the presence or absence of gallbladder stones. The factors associated with gallstone recurrence were analyzed by univariate analysis and Cox regression.

Results: In total, 466 eligible patients were included in the study, and 438 patients (180 men and 258 women) completed the 2-year postoperative follow-up. The follow-up rate was 94.0%. Recurrence of gallstones was detected in 5.71% (25/438) of the patients. Univariate analysis revealed five risk factors for the recurrence of gallstones. Multivariate Cox regression analysis showed that multiple gallstones, a gallbladder wall thickness of ≥4 mm, and a family history of gallbladder stones were the three predictive factors for postoperative recurrence of gallstones (P < 0.05).

Conclusion: The overall 2-year recurrence rate of gallstones after the operation was 5.71%. Multiple gallstones, a gallbladder wall thickness of ≥4 mm, and a family history of gallstones were the three risk factors associated with early postoperative recurrence of gallstones.

Gallstone disease and nonalcoholic fatty liver disease in patients with type 2 diabetes: a cross-sectional study

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) and gallstone disease (GSD) often coexist in the general population owing to shared risk factors. This study explored the relationship between NAFLD and GSD in patients with type 2 diabetes.

METHODS

We conducted a retrospective cross-sectional analysis of 4325 patients with type 2 diabetes. GSD and NAFLD were confirmed using ultrasonography. GSD was defined as either asymptomatic gallstones or previous cholecystectomy, and each was analyzed separately.

RESULT

There was no significant difference in the prevalence of GSD between patients with and without NAFLD (23.8% vs. 21.2%, P = 0.15). After case-control matching (1:1) of baseline data such as age, sex, duration of diabetes, and HbA1c between patients with and without NAFLD, there was still no significant difference in the prevalence of GSD (25.5% vs. 23.6%, P = 0.15). The prevalence of NAFLD in patients with asymptomatic gallstones was lower than that of patients without GSD (38.6% vs. 47.3%, P < 0.001), whereas the prevalence in those who had undergone cholecystectomy was much higher (61.2% vs. 47.3%, P < 0.001). The ratio of cholecystectomy to asymptomatic gallstone in patients with or without NAFLD was 1.97 and 0.79, respectively. The rate of cholecystectomy was higher in the patients with NAFLD than in those without NAFLD (15.8% vs. 9.3%, P < 0.001), consistent with the result after case-control matching (17.3% vs. 11.2%, P < 0.001). Multivariate logistic regression analysis, after adjusting for numerous potential confounding factors, revealed that GSD (OR = 1.241, 95%CI: 1.036-1.488, P = 0.002) and cholecystectomy (OR = 1.946, 95%CI: 1.546-2.445, P < 0.001) were both strongly associated with NAFLD. However, asymptomatic gallstone (OR = 0.663, 95%CI: 0.513-0.856, P = 0.002) seemed to be negatively correlated with NAFLD.

CONCLUSIONS

The prevalence of GSD was similar in patients with type 2 diabetes with and without NAFLD. The higher proportion of cholecystectomy and lower proportion of asymptomatic gallstones in patients with NAFLD suggests that NAFLD may increase the risk of complications of GSD.

Cholecystectomy and subsequent risk of Parkinson's disease: a nationwide retrospective cohort study

Growing evidence has suggested that the gut-brain axis plays an important role in the pathogenesis of Parkinson's disease (PD), and that this role is mediated by the interactions between bile acids (BAs) and intestinal microbiota. Given that cholecystectomy can lead to alterations in BAs and gut microbiota, we investigated whether cholecystectomy is linked to a higher risk of PD. We constructed a cohort of patients with an operation code of cholecystectomy from 2010 to 2015 (n = 161,838) and age- and sex-matched control subjects without cholecystectomy (n = 286,135) using the National Health Insurance Service database. Incident PD was traced over a maximum observation period of 7 years. We identified 1404 incident PD cases during 1,631,265 person-years of follow-up. The cholecystectomy group showed an elevated risk of PD compared to the control group, even after adjusting for potential confounding factors (adjusted hazard ratio [HR] 1.14, 95% confidence interval [CI] 1.02-1.27). When the data were split by sex, the risk elevation was significant in men (adjusted HR 1.22, 95% CI 1.06-1.41), but not in women (adjusted HR 1.03, 95% CI 0.88-1.22). Our results provide evidence that cholecystectomy is associated with an increased risk of developing PD. This association differed between men and women, suggesting sex-specific effects of cholecystectomy on the risk of PD.

Variation of enterohepatic circulation observed with 75SeHCAT images in the first three hours. Scintigraphic patterns and analysis of their association with the diagnosis of bile acid malabsorption

OBJETIVE

To evaluate the enterohepatic circulation of 75-Selenium turoselecolic acid (⁷⁵Se-SeHCAT) during the first 3 h and its correlation with the abdominal retention at the 7th day (AR₇), as contribution to the clinical study of biliar acid malabsorption (BAM).

MATERIALS AND METHODS

38 patients with chronic diarrhea were retrospectively studied. Acquisition protocol included static abdominal images at 1st, 2nd and 3rd hour and the 7th day after oral administration of the radiopharmaceutical. Images of 1-3 h determined 5 patterns of enterohepatic circulation that, due to their location, were characterized as: 1) gallbladder 2-3 h, 2) gallbladder 3 h, 3) gallbladder-abdomen 2-3 h, 4) abdomen, 5) upper left abdomen. The association of these patterns with the AR₇ (Fisher, STATA) were investigated. Patients were classified as Non BAM (AR₇ > 15%), mild-BAM (AR₇ 15-10%), moderate-BAM (AR₇ 10-5%) or severe-BAM (AR₇ < 5%).

RESULTS

19 patients had an AR₇ diagnostic of BAM (7 mild-BAM, 5 moderate-BAM, 7 severe-BAM). The pattern "gallbladder at 2-3 h" was statistically associated with Non BAM (p 0,008), while "gallbladder-abdomen at 2-3 h" was correlated with having BAM (p 0,029).

CONCLUSION

Variations detected at the abdominal level in images during the first 3 h were associated with changes in intestinal absorption and the incorporation of the radiopharmaceutical into the pool of bile acids, so visual interpretation of the images at 2nd and 3rd hour could be useful in the final assessment of the study.