The Role of Diet in the Pathogenesis of Cholesterol Gallstones

Acute Cholecystitis: A Review

IMPORTANCE

Gallbladder disease affects approximately 20 million people in the US. Acute cholecystitis is diagnosed in approximately 200 000 people in the US each year.

OBSERVATIONS

Gallstone-associated cystic duct obstruction is responsible for 90% to 95% of the cases of acute cholecystitis. Approximately 5% to 10% of patients with acute cholecystitis have acalculous cholecystitis, defined as acute inflammation of the gallbladder without gallstones, typically in the setting of severe critical illness. The typical presentation of acute cholecystitis consists of acute right upper quadrant pain, fever, and nausea that may be associated with eating and physical examination findings of right upper quadrant tenderness. Ultrasonography of the right upper quadrant has a sensitivity of approximately 81% and a specificity of approximately 83% for the diagnosis of acute cholecystitis. When an ultrasound result does not provide a definitive diagnosis, hepatobiliary scintigraphy (a nuclear medicine study that includes the intravenous injection of a radiotracer excreted in the bile) is the gold standard diagnostic test. Following diagnosis, early (performed within 1-3 days) vs late (performed after 3 days) laparoscopic cholecystectomy is associated with improved patient outcomes, including fewer composite postoperative complications (11.8% for early vs 34.4% for late), a shorter length of hospital stay (5.4 days vs 10.0 days), and lower hospital costs. During pregnancy, early laparoscopic cholecystectomy, compared with delayed operative management, is associated with a lower risk of maternal-fetal complications (1.6% for early vs 18.4% for delayed) and is recommended during all trimesters. In people older than 65 years of age, laparoscopic cholecystectomy is associated with lower mortality at 2-year follow-up (15.2%) compared with nonoperative management (29.3%). A percutaneous cholecystostomy tube, in which a drainage catheter is placed in the gallbladder lumen under image guidance, is an effective therapy for patients with an exceptionally high perioperative risk. However, percutaneous cholecystostomy tube placement in a randomized trial was associated with higher rates of postprocedural complications (65%) compared with laparoscopic cholecystectomy (12%). For patients with acalculous acute cholecystitis, percutaneous cholecystostomy tube should be reserved for patients who are severely ill at the time of diagnosis; all others should undergo a laparoscopic cholecystectomy.

CONCLUSIONS AND RELEVANCE

Acute cholecystitis, typically due to gallstone obstruction of the cystic duct, affects approximately 200 000 people in the US annually. In most patient populations, laparoscopic cholecystectomy, performed within 3 days of diagnosis, is the first-line therapy for acute cholecystitis.

High dietary ω-6:ω-3 PUFA ratio and simple carbohydrates as a potential risk factors for gallstone disease: A cross-sectional study

BACKGROUND & AIMS

Gallstone disease (GD) is a major cause for consultation at general surgery services worldwide. In fact, GD has a strong relationship with environmental factors. However, specific characteristics in the Mexican population have not been established. The aim of this study was to compare the dietary components, physical activity, body composition and serum lipids in women with and without GD.

METHODS

54 women with GD and 75 without GD from West Mexico were enrolled in a cross-sectional study. Dietary intake was obtained through a habitual day food record and analyzed using the Nutritionist Pro™ software. Physical activity was evaluated in accordance with WHO recommendations. Body fat percentage (BF%) was estimated by bioimpedance (InBody 370) and serum lipids were measured using dry chemistry (Vitros-250 Analyzer). Student's t-test and binary logistic regression model were used.

RESULTS

Women with GD presented a higher BF% (40 ± 8.7 vs 35.21 ± 9.8%, p = 0.004), an elevated dietary ω-6:ω-3 polyunsaturated fatty acids (PUFA) ratio (18.0 ± 11.4 vs 10.9 ± 4.7, p<0.001) and a higher simple carbohydrates (sCH) intake (28.3 ± 17.8 vs 13.23 ± 8.2%, p<0.001) as well as lower HDL-cholesterol levels (37.43 ± 8.5 vs 46.6 ± 12.02 mg/dL, p<0.001) compared with women without GD. Furthermore, it was foun d a higher ω-6:ω-3 PUFA ratio (OR: 3.9, 95% CI 1.52-10.38, p = 0.005) and excessive sCH consumption (OR: 7.4, 95% CI 1.92-28.65, p = 0.004).

CONCLUSION

We suggest that a high dietary ω-6:ω-3 PUFA ratio and an excessive sCH intake are associated with an increased risk of GD in women.

RNA Sequencing Analysis of Gene Expression by Electroacupuncture in Guinea Pig Gallstone Models

BACKGROUND

Clinical studies have shown that electroacupuncture (EA) promotes gallbladder motility and alleviates gallstone. However, the mechanism underlying the effects of EA on gallstone is poorly understood. In this study, the mRNA transcriptome analysis was used to study the possible therapeutic targets of EA.

METHODS

Hartley SPF guinea pigs were employed for the gallstone models. Illumina NovaSeq 6000 platform was used for the RNA sequencing of guinea pig gallbladders in the normal group (Normal), gallstone model group (Model), and EA-treated group (EA). Differently expressed genes (DEGs) were examined separately in Model vs. Normal and EA vs. Model. DEGs reversed by EA were selected by comparing the DEGs of Model vs. Normal and EA vs. Model. Biological functions were enriched by gene ontology (GO) analysis. The protein-protein interaction (PPI) network was analyzed.

RESULTS

After 2 weeks of EA, 257 DEGs in Model vs. Normal and 1704 DEGs in EA vs. Model were identified. 94 DEGs reversed by EA were identified among these DEGs, including 28 reversed upregulated DEGs and 66 reversed downregulated DEGs. By PPI network analysis, 10 hub genes were found by Cytohubba plugin of Cytoscape. Quantitative real-time PCR (qRT-PCR) verified the changes.

CONCLUSION

We identified a few GOs and genes that might play key roles in the treatment of gallstone. This study may help understand the therapeutic mechanism of EA for gallstone.

Changes in the interstitial cells of Cajal in the gallbladder of guinea pigs fed a lithogenic diet

Cholesterol cholelithiasis is a common disease and gallbladder hypomotility may underlie its pathogenesis. Interstitial cells of Cajal (ICCs) in the gallbladder serve vital roles in regulating gallbladder motility. The aim of the present study was to investigate changes in gallbladder ICCs during the development of cholesterol cholelithiasis. A total of 40 male guinea pigs were randomly assigned to four groups and fed a standard diet (SD) or lithogenic diet (LD) for 2 or 8 weeks. The LD significantly increased the total cholesterol levels in the serum and bile, as well as the serum levels of high-density lipoprotein-cholesterol and low-density lipoprotein-cholesterol after 2 and 8 weeks. The LD also significantly increased and decreased the number of gallbladder ICCs at 2 and 8 weeks, respectively, by regulating the stem cell factor/C-kit pathway. Moreover, the ultrastructure of gallbladder ICCs was significantly altered after 8 weeks, and the protein expression levels of connexin 43 in the gallbladder were differentially altered after 2 and 8 weeks. Finally, cholecystokinin receptor type A (CCK1R) expression in the gallbladder was assessed. In gallbladder ICCs, its expression was significantly increased and decreased after 2 and 8 weeks, respectively. In conclusion, these results demonstrate that the density, ultrastructure and CCK1R expression levels of gallbladder ICCs are differentially altered at various stages of cholesterol cholelithiasis progression, indicating that gallbladder ICCs may be considered a potential therapeutic target for treatment of cholesterol cholelithiasis.

Effect and related mechanism of Yinchenhao decoction on mice with lithogenic diet-induced cholelithiasis

The aim of the present study was to investigate the effects and the underlying mechanisms of Yinchenhao Decoction (YCHD), a traditional Chinese medicine formulation, on C57BL/6 mice with lithogenic diet (LD)-induced cholelithiasis. The condition of cholelithiasis was evaluated using a six-level criteria. Levels of alanine aminotransferase (ALT), alkaline phosphatase (ALP), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) in the serum and liver tissue were measured using enzyme colorimetry. Concentrations of TC, phospholipids (PL) and total bile acids (TBA) in the bile were measured to calculate the cholesterol saturation index. Liver histopathology was microscopically observed and mRNA expression levels of ABCG5, ABCG8, SRBI, ABCB4, ABCB11 and NPC1L1 involved in cholesterol metabolism were measured using reverse transcription-quantitative PCR. The results showed that feeding mice the LD induced cholelithiasis, along with abnormal serum biochemical indices and imbalances in biliary cholesterol homeostasis. Increased ALT and ALP levels in the serum and ALT, ALP, TC and LDL-C levels in the serum and liver indicated the existence of hepatocyte injury, which were consistent with the pathological changes. YCHD treatment ameliorated the serum and hepatic biochemical abnormalities and adjusted the biliary imbalance. In addition, elevated expression of ATP-binding cassette subfamily G member 5/8, scavenger receptor class B type I and Niemann-Pick C1 Like 1 in the liver and small intestine were observed at the onset of cholelithiasis but were reversed by YCHD. Taken together, results from the present study suggest that YCHD ameliorated LD-induced cholelithiasis mice, which may be caused by improvements in biliary cholesterol supersaturation and regulation of cholesterol metabolism.

The long non-coding RNA MEG3 plays critical roles in the pathogenesis of cholesterol gallstone

Background

Cholesterol gallstone (CG) is the most common gallstone disease, which is induced by biliary cholesterol supersaturation. The purpose of this study is to investigate the pathogenesis of CG.

Methods

Sixteen mice were equally and randomly divided into model group and normal control group. The model group was fed with lithogenic diets to induce CG, and then gallbladder bile lipid analysis was performed. After RNA-seq library was constructed, differentially expressed mRNAs (DE-mRNAs) and differentially expressed lncRNAs (DE-lncRNAs) between model group and normal control group were analyzed by DESeq2 package. Using the cluster Profiler package, enrichment analysis for the DE-mRNAs was carried out. Based on Cytoscape software, the protein-protein interaction (PPI) network and competing endogenous RNA (ceRNA) network were built. Using quantitative real-time reverse transcription-PCR (qRT-PCR) analysis, the key RNAs were validated.

Results

The mouse model of CG was suc cessfully established, and then 181 DE-mRNAs and 33 DE-lncRNAs between model and normal groups were obtained. Moreover, KDM4A was selected as a hub node in the PPI network, and lncRNA MEG3 was considered as a key lncRNA in the regulatory network. Additionally, the miR-107-5p/miR-149-3p/miR-346-3-MEG3 regulatory pairs and MEG3-PABPC4/CEP131/NUMB1 co-expression pairs existed in the regulatory network. The qRT-PCR analysis showed that KDM4A expression was increased, and the expressions of MEG3, PABPC4, CEP131, and NUMB1 were downregulated.

Conclusion

These RNAs might be related to the pathogenesis of CG.

Advances in Risk Factors for Recurrence of Common Bile Duct Stones

Choledocholithiasis is a chronic common disease. The incidence of cholelithiasis is 5%-15%, of which 5%-30% are combined with Choledocholithiasis. Although endoscopic cholangiopancreatography (ERCP) + endoscopic sphincterotomy (EST) is the most common treatment procedure, which clearance rate is up to 95%, the incidence of recurrent choledocholithiasis was 4%-25%. The risk factors of recurrence after choledocholithiasis clearance are the focuses of current researches, which are caused by multiple factors. We first systematically summarize the risk factors of common bile duct stones (CBDS) recurrence into five aspects: first-episode stone related factors, congenital factors, biological factors, behavioral intervention factors, and the numbers of stone recurrence.

Regulation of Cholesterol Metabolism by Bioactive Components of Soy Proteins: Novel Translational Evidence

Hypercholesterolemia represents one key pathophysiological factor predisposing to increasing risk of developing cardiovascular disease worldwide. Controlling plasma cholesterol levels and other metabolic risk factors is of paramount importance to prevent the overall burden of disease emerging from cardiovascular-disease-related morbidity and mortality. Dietary cholesterol undergoes micellization and absorption in the small intestine, transport via blood, and uptake in the liver. An important amount of cholesterol originates from hepatic synthesis, and is secreted by the liver into bile together with bile acids (BA) and phospholipids, with all forming micelles and vesicles. In clinical medicine, dietary recommendations play a key role together with pharmacological interventions to counteract the adverse effects of chronic hypercholesterolemia. Bioactive compounds may also be part of initial dietary plans. Specifically, soybean contains proteins and peptides with biological activity on plasma cholesterol levels and this property makes soy proteins a functional food. Here, we discuss how soy proteins modulate lipid metabolism and reduce plasma cholesterol concentrations in humans, with potential outcomes in improving metabolic- and dyslipidemia-related conditions.

An inverse association of weight and the occurrence of asymptomatic gallbladder stone disease in hypercholesterolemia patients: a case-control study

Background

Despite the fact that the majority of gallstones formed in the gallbladder are mainly composed of cholesterol, as they are formed from cholesterol-supersaturated bile, and hypercholesterolemia is a common metabolic disorder, which is closely related to cardiac, hepatic, renal and other oxidative damage inflammation and necrosis, there is still no consensus regarding the contribution of blood serum lipids in the pathogenesis of gallbladder stone disease (GSD). This study aimed to investigate the relationship between hypercholesterolemia and the risk of new-onset asymptomatic GSD, and to determine the prevalence of factors associated with new-onset asymptomatic GSD in patients with hypercholesterolemia.

Methods

In this study, 927 Chinese patients with new-onset asymptomatic gallstone disease and 845 healthy controls were enrolled starting from August 2012. Patients were matched for age, gender, race, occupation, systolic blood pressure, diastolic blood pressure, and fasting blood glucose levels (FBG). Body mass index (BMI), nonalcoholic fatty liver disease (NAFLD) and serum lipids indexes were compared and the relationships between BMI, blood lipid and gallbladder stone hazards were examined by logistic multivariate regression models.

Results

The result showed a significantly higher morbidity with GSD in hypercholesterolemia than non-hypercholesterolemia patients (Χ² = 17.211, P < 0.001). Of hypercholesterolemia patients, low density lipoprotein (OR = 1.493, P = 0.029) and NAFLD (OR = 2.723, P = 0.022) were significant risk factors for GSD, while being male (OR = 0.244, P = 0.033), weight (OR = 0.961, P = 0.022), high density lipoprotein (OR = 0.305, P < 0.001), and FBG (OR = 0.687, P = 0.034) were significantly negatively correlated with GSD in univariate analysis. Multivariate logistic regression indicated weakly positive correlations with NAFLD (OR = 3.284, P = 0.054), and significant negative correlations with weight (OR = 0.930, P = 0.018), HDL-c (OR = 0.144, P < 0.001), and GSD.

Conclusion

Hypercholesterolemia acts as an independent risk factor for new-onset asymptomatic GSD, while obesity and NAFLD are synergistic factors. Interestingly, it is first reported that elevated weight was inversely associated with GSD in patients with hypercholesterolemia. The results of this study suggest that effective control of hyperlipidemia is of greater significance than weight loss, which might make the situation worse, in the prevention of GSD in obese patients with hyperlipidemia.

Physical Activity Modulating Lipid Metabolism in Gallbladder Diseases

Physical activity encompasses a series of overall benefits on cardiovascular health and metabolic disorders. Research has recently focused on the hepatobiliary tract, as an additional target of the health-related outcomes of different types of physical exercise. Here, we focus on the global features of physical activity with respect to exercise modality and intensity, and on studies linking physical activity to lipid metabolism, gallbladder diseases (gallstones, symptoms, complications and health-related quality of life), gallbladder motor-function, enterohepatic circulation of bile acids, and systemic metabolic inflammation. Additional studies need to unravel the pathophysiological mechanisms involved in both beneficial and harmful effects of physical activity in populations with different metabolic conditions.

Cholesterol cholelithiasis: part of a systemic metabolic disease, prone to primary prevention

Cholesterol gallstone disease have relationships with various conditions linked with insulin resistance, but also with heart disease, atherosclerosis, and cancer. These associations derive from mechanisms active at a local (i.e. gallbladder, bile) and a systemic level and are involved in inflammation, hormones, nuclear receptors, signaling molecules, epigenetic modulation of gene expression, and gut microbiota. Despite advanced knowledge of these pathways, the available therapeutic options for symptomatic gallstone patients remain limited. Therapy includes oral litholysis by the bile acid ursodeoxycholic acid (UDCA) in a small subgroup of patients at high risk of postdissolution recurrence, or laparoscopic cholecystectomy, which is the therapeutic radical gold standard treatment. Cholecystectomy, however, may not be a neutral event, and potentially generates health problems, including the metabolic syndrome. Areas covered: Several studies on risk factors and pathogenesis of cholesterol gallstone disease, acting at a systemic level have been reviewed through a PubMed search. Authors have focused on primary prevention and novel potential therapeutic strategies. Expert commentary: The ultimate goal appears to target the manageable systemic mechanisms responsible for gallstone occurrence, pointing to primary prevention measures. Changes must target lifestyles, as well as experimenting innovative pharmacological tools in subgroups of patients at high risk of developing gallstones.

Metabolic status and lifestyle factors associated with gallbladder polyps: a covariance structure analysis

Background

Gallbladder Polyps (GBP) are highly prevalent in China; however, the etiology of GBP has not been clearly defined. This study explored the associations between lifestyle factors and GBP and whether it mediated by metabolic factors or not.

Methods

A total of 487 newly diagnosed GBP cases and 502 healthy controls were involved in this study. A questionnaire was used to investigate the socio-demographic characteristics and lifestyle factors. Food Intake Frequencies Questionnaire was used to obtain the food intake frequencies of seven food categories. Blood was tested for lipid profiles, fasting blood glucose and blood urine acid. A Covariance Structure Analysis was used in the analysis to explore the possible pathways between socio-demographic characteristics, lifestyle factors, metabolic factor and GBP.

Results

The Covariance Structure Analysis showed that a higher BMI and elevated triglyceride level mediated the association between age and GBP. Lifestyle factors (smoking and drinking) and higher intake frequencies of fatty food (meat and viscera) also linked to higher BMI and higher triglyceride level, respectively, which were associated with GBP.

Conclusion

In conclusion, age and lifestyle factors might be indirectly related with GBP through BMI and the triglyceride pathway.

Genetics of gallstone disease

BACKGROUND

Gallstone disease (GD) belongs to the most frequent disorders in gastroenterology and causes high costs in our health-care systems. Gallstones are uncommon in children but frequent in adults, in particular in women, and are triggered by exogenous risk factors. Here, we summarize the current knowledge concerning the contribution of inherited predisposition to gallstone risk.

DESIGN

In this review, we present the current data and recent research on the genetics of gallstone disease.

RESULTS

Several GD-predisposing gene variants have been reported, with most prominent effects being conferred by a common variant (p.D19H) of the hepatic and intestinal cholesterol transporter ABCG5/G8. A smaller group of patients might develop gallstones primarily due low phosphatidylcholine concentrations in bile as a result of loss-of-function mutations of the ABCB4 transporter (low phospholipid-associated cholelithiasis syndrome). Regardless of the origin, the risk factors for gallstones lead to the supersaturation of bile with insoluble compounds, in particular cholesterol. As result, cholesterol stones develop and present the most frequent type of gallstones. Laparoscopic cholecystectomy with low morbidity and mortality is currently the most common and effective method for the therapy of symptomatic gallbladder stones.

CONCLUSIONS

Gallstone disease represents a multifactorial condition and previous studies have identified the major genetic contributors to gallstone formation. The increasing knowledge about the pathomechanisms of hepatobiliary metabolism and GD as well as the identification of additional risk factors might help to overcome the current invasive therapy by specific lifestyle intervention and precise molecular treatment.

Recent advances in understanding and managing cholesterol gallstones

The high prevalence of cholesterol gallstones, the availability of new information about pathogenesis, and the relevant health costs due to the management of cholelithiasis in both children and adults contribute to a growing interest in this disease. From an epidemiologic point of view, the risk of gallstones has been associated with higher risk of incident ischemic heart disease, total mortality, and disease-specific mortality (including cancer) independently from the presence of traditional risk factors such as body weight, lifestyle, diabetes, and dyslipidemia. This evidence points to the existence of complex pathogenic pathways linking the occurrence of gallstones to altered systemic homeostasis involving multiple organs and dynamics. In fact, the formation of gallstones is secondary to local factors strictly dependent on the gallbladder (that is, impaired smooth muscle function, wall inflammation, and intraluminal mucin accumulation) and bile (that is, supersaturation in cholesterol and precipitation of solid crystals) but also to "extra-gallbladder" features such as gene polymorphism, epigenetic factors, expression and activity of nuclear receptors, hormonal factors (in particular, insulin resistance), multi-level alterations in cholesterol metabolism, altered intestinal motility, and variations in gut microbiota. Of note, the majority of these factors are potentially manageable. Thus, cholelithiasis appears as the expression of systemic unbalances that, besides the classic therapeutic approaches to patients with clinical evidence of symptomatic disease or complications (surgery and, in a small subgroup of subjects, oral litholysis with bile acids), could be managed with tools oriented to primary prevention (changes in diet and lifestyle and pharmacologic prevention in subgroups at high risk), and there could be relevant implications in reducing both prevalence and health costs.