Nonobese diabetic mice have diminished gallbladder motility and shortened crystal observation time

Histopathological changes in gall bladder mucosa in relation to the number, and size of gallstones, and analysis of the findings in the context of age distribution of the patients: A perspective

Backgrounds/Aims

To study histopathological changes in gall bladder mucosa in cholelithiasis patients, and analyse their relation to the number and size of gallstones. These findings were evaluated in the context of age distribution of the study population.

Methods

One hundred cases of cholecystectomy were part of the study, which was conducted in collaboration with the pathology department. The time period of the study was January 2020 to June 2021.

Results

Maximum cases had multiple stones (69.0%), while one third cases (31.0%) had solitary stones. While initial univariate analysis showed age (odds ratio [OR], 6.882; p = 0.043), gallstone number (OR, 9.1; p = 0.050), gallstone size (OR, 17.111; p = 0.013), and duration of symptom (OR, 34.125; p = 0.001) to be significant risk factors associated with gallbladder carcinoma, multivariate analysis found none of these variables to be significant. However, conditional multivariate analysis for the duration of symptom (p = 0.008; OR, 21.118) yielded significant p- value. With histopathological diagnoses, 5% of cases had gallbladder cancer.

Conclusions

This study shed light on the rising incidence of cholelithiasis in the young population and the high rate of gallbladder carcinoma in Punjab, India. Although gall stone characteristics (size, number) and patient age appeared to be significant risk factors when their individual relation with gallbladder carcinoma was studied, multivariate analysis, could not prove that. Conditional multivariate analysis showed the duration of symptom to be the only significant risk factor associated with gallbladder carcinoma. Further research with larger sample size is needed to study the rising incidence of gallbladder carcinoma, and the risk factors associated with it.

CCR9 Expressing T Helper and T Follicular Helper Cells Exhibit Site-Specific Identities During Inflammatory Disease

CD4⁺ T helper (Th) cells that express the gut homing chemokine receptor CCR9 are increased in the peripheral blood of patients with inflammatory bowel disease and Sjögren's syndrome and in the inflamed lesions of autoimmune diseases that affect the accessory organs of the digestive system. However, despite the important role of the GIT in both immunity and autoimmunity, the nature of CCR9-expressing cells in GIT lymphoid organs and their role in chronic inflammatory diseases remains unknown. In this study, we analyzed the characteristics of CCR9⁺ Th and T follicular helper (Tfh) cells in GIT associated lymphoid tissues in health, chronic inflammation and autoimmunity. Our findings reveal an association between the transcriptome and phenotype of CCR9⁺ Th in the pancreas and CCR9⁺ Tfh cells from GIT-associated lymphoid tissues. GIT CCR9⁺ Tfh cells exhibited characteristics, including a Th17-like transcriptome and production of effector cytokines, which indicated a microenvironment-specific signature. Both CCR9⁺ Tfh cells and CCR9⁺ Th cells from GIT-associated lymphoid tissues migrated to the pancreas. The expression of CCR9 was important for migration of both subsets to the pancreas, but Tfh cells that accumulated in the pancreas had downmodulated expression of CXCR5. Taken together, the findings provide evidence that CCR9⁺ Tfh cells and Th cells from the GIT exhibit plasticity and can accumulate in distal accessory organs of the digestive system where they may participate in autoimmunity.

A short review of adipokines, smooth muscle and uterine contractility

Obesity is a major health problem worldwide. The prevalence of obesity is increasing in both developed and developing countries. In the UK, for example, 60% of adults are overweight and 25% are obese. Obesity is associated with many pathological complications including respiratory, cardiovascular and endocrine, but it also affects fertility and is associated with many reproductive complications. This has led us and others to investigate links between women with high BMI, pregnancy outcome and uterine function. These studies in turn have led investigators to ask how obesity can have such an impact on reproduction and, as part of this, to consider the role of the adipokines released from adipose tissues. Our focus in this short review is on adipokines and myometrial activity, and for completeness we overview their effects on other smooth muscles. To date four adipokines (leptin, visfatin, apelin and ghrelin) have been investigated and all affect myometrial contractility, but some more potently than others. We consider the possible mechanisms involved in how adipokines may modify uterine contractility, and discuss the potential impact on labor and delivery.

ABCG5/G8 deficiency in mice reduces dietary triacylglycerol and cholesterol transport into the lymph

The adenosine triphosphate-binding cassette (ABC) transporter G5/G8 is critical in protecting the body from accumulating dietary plant sterols. Expressed in the liver and small intestine, it transports plant sterols into the biliary and intestinal lumens, thus promoting their excretion. The extent to which G5/G8 regulates cholesterol absorption remains unclear. G5/G8 is also implicated in reducing the absorption of dietary triacylglycerols (TAG) by unknown mechanisms. We hypothesized that G5/G8 suppresses the production of chylomicrons, and its deficiency would enhance the absorption of both dietary TAG and cholesterol. The aim of this study was to investigate the effects of G5/G8 deficiency on lipid uptake and secretion into the lymph under steady-state conditions. Surprisingly, compared with wild-type mice (WT) (n = 9), G5/G8 KO (n = 13) lymph fistula mice given a continuous intraduodenal infusion of [3H]-TAG and [14C]-cholesterol showed a significant (P < 0.05) reduction in lymphatic transport of both [(3)H]-TAG and [(14)C]-cholesterol, concomitant with a significant (P < 0.05) increase of [(3)H]-TAG and [(14)C]-cholesterol accumulated in the intestinal lumen. There was no difference in the total amount of radiolabeled lipids retained in the intestinal mucosa between the two groups. G5/G8 KO mice given a bolus of TAG showed reduced intestinal TAG secretion compared with WT, suggesting an independent role for G5/G8 in facilitating intestinal TAG transport. Our data demonstrate that G5/G8 deficiency reduces the uptake and secretion of both dietary TAG and cholesterol by the intestine, suggesting a novel role for the sterol transporter in the formation and secretion of chylomicrons.

Prevalences of and risk factors for biliary stones and gallbladder polyps in a large Chinese population

OBJECTIVES

This study aimed to identify the prevalences of and risk factors associated with the development of gallbladder stones and polyps in a large Chinese population.

METHODS

Prevalences of and risk factors for biliary stones and gallbladder polyps were retrospectively investigated among subjects who underwent a general check-up at the Health Screening Centres of Peking Union Medical College Hospital and Beijing Charity Hospital between January 2007 and June 2010.

RESULTS

A total of 60,064 people were enrolled in the study. Overall prevalences of biliary stones and gallbladder polyps were 4.2% (n= 2527) and 6.9% (n= 4119), respectively. Risk factors associated with increased odds ratios (ORs) for the development of biliary stones were female gender (OR = 1.51), age ≥ 50 years (OR = 2.09), history of hypertension (OR = 1.37), thickened gallbladder wall (cholecystitis) (OR = 1.98), fasting blood glucose ≥ 6.10 mmol/l (OR = 1.27), body mass index ≥ 25 kg/m(2) (OR = 1.25), systolic blood pressure ≥ 140 mmHg (OR = 1.31) and diastolic blood pressure ≥ 90 mmHg (OR = 1.44). Factors associated with gallbladder polyps were female gender (OR = 0.66), thickened gallbladder wall (OR = 2.09), negativity for hepatitis B surface antigen (HBsAg) and positivity for hepatitis B core antibody (anti-HBc) (OR = 2.61), and positivity for both HBsAg and anti-HBc (OR = 3.21).

CONCLUSIONS

  Prevalences of biliary stones and gallbladder polyps among Chinese people are similar to those reported for other populations. Biliary stones appear to be associated with female gender, age, obesity, blood glucose, blood pressure and cholecystitis. Male gender, hepatitis B virus infection and cholecystitis were strong risk factors for the formation of gallbladder polyps.

Prevalences of and risk factors for biliary stones and gallbladder polyps in a large Chinese population

OBJECTIVES

This study aimed to identify the prevalences of and risk factors associated with the development of gallbladder stones and polyps in a large Chinese population.

METHODS

Prevalences of and risk factors for biliary stones and gallbladder polyps were retrospectively investigated among subjects who underwent a general check-up at the Health Screening Centres of Peking Union Medical College Hospital and Beijing Charity Hospital between January 2007 and June 2010.

RESULTS

A total of 60,064 people were enrolled in the study. Overall prevalences of biliary stones and gallbladder polyps were 4.2% (n= 2527) and 6.9% (n= 4119), respectively. Risk factors associated with increased odds ratios (ORs) for the development of biliary stones were female gender (OR = 1.51), age ≥ 50 years (OR = 2.09), history of hypertension (OR = 1.37), thickened gallbladder wall (cholecystitis) (OR = 1.98), fasting blood glucose ≥ 6.10 mmol/l (OR = 1.27), body mass index ≥ 25 kg/m(2) (OR = 1.25), systolic blood pressure ≥ 140 mmHg (OR = 1.31) and diastolic blood pressure ≥ 90 mmHg (OR = 1.44). Factors associated with gallbladder polyps were female gender (OR = 0.66), thickened gallbladder wall (OR = 2.09), negativity for hepatitis B surface antigen (HBsAg) and positivity for hepatitis B core antibody (anti-HBc) (OR = 2.61), and positivity for both HBsAg and anti-HBc (OR = 3.21).

CONCLUSIONS

  Prevalences of biliary stones and gallbladder polyps among Chinese people are similar to those reported for other populations. Biliary stones appear to be associated with female gender, age, obesity, blood glucose, blood pressure and cholecystitis. Male gender, hepatitis B virus infection and cholecystitis were strong risk factors for the formation of gallbladder polyps.

Disruption of the murine protein kinase Cbeta gene promotes gallstone formation and alters biliary lipid and hepatic cholesterol metabolism

The protein kinase C (PKC) family of Ca(2+) and/or lipid-activated serine-threonine protein kinases is implicated in the pathogenesis of obesity and insulin resistance. We recently reported that protein kinase Cβ (PKCβ), a calcium-, diacylglycerol-, and phospholipid-dependent kinase, is critical for maintaining whole body triglyceride homeostasis. We now report that PKCβ deficiency has profound effects on murine hepatic cholesterol metabolism, including hypersensitivity to diet-induced gallstone formation. The incidence of gallstones increased from 9% in control mice to 95% in PKCβ(-/-) mice. Gallstone formation in the mutant mice was accompanied by hyposecretion of bile acids with no alteration in fecal bile acid excretion, increased biliary cholesterol saturation and hydrophobicity indices, as well as hepatic p42/44(MAPK) activation, all of which enhance susceptibility to gallstone formation. Lithogenic diet-fed PKCβ(-/-) mice also displayed decreased expression of hepatic cholesterol-7α-hydroxylase (CYP7A1) and sterol 12α-hydroxylase (CYP8b1). Finally, feeding a modified lithogenic diet supplemented with milk fat, instead of cocoa butter, both increased the severity of and shortened the interval for gallstone formation in PKCβ(-/-) mice and was associated with dramatic increases in cholesterol saturation and hydrophobicity indices. Taken together, the findings reveal a hitherto unrecognized role of PKCβ in fine tuning diet-induced cholesterol and bile acid homeostasis, thus identifying PKCβ as a major physiological regulator of both triglyceride and cholesterol homeostasis.

A subset of interleukin-21+ chemokine receptor CCR9+ T helper cells target accessory organs of the digestive system in autoimmunity

This study describes a CD4+ T helper (Th) cell subset marked by coexpression of the cytokine interleukin 21 (IL-21) and the gut-homing chemokine receptor CCR9. Although CCR9+ Th cells were observed in healthy mice and humans, they were enriched in the inflamed pancreas and salivary glands of NOD mice and in the circulation of Sjögren's syndrome patients. CCR9+ Th cells expressed large amounts of IL-21, inducible T cell costimulator (ICOS), and the transcription factors Bcl6 and Maf, and also supported antibody production from B cells, thereby resembling T follicular B helper (Tfh) cells. However, in contrast to Tfh cells, CCR9+ Th cells displayed limited expression of CXCR5 and the targets of CCR9+ Th cells were CD8+ T cells whose responsiveness to IL-21 was necessary for the development of diabetes. Thus, CCR9+ Th cells are a subset of IL-21-producing T helper cells that influence regional specification of autoimmune diseases that affect accessory organs of the digestive system.

Gender and metabolic differences of gallstone diseases

AIM: To investigate the risk factors for gallstone disease in the general population of Chengdu, China.

METHODS: This study was conducted at the West China Hospital. Subjects who received a physical examination at this hospital between January and December 2007 were included. Body mass index, blood pressure, fasting plasma glucose, serum lipid and lipoproteins concentrations were analyzed. Gallstone disease was diagnosed by ultrasound or on the basis of a history of cholecystectomy because of gallstone disease. Unconditional logistic regression analysis was used to investigate the risk factors for gallstone disease, and the Chi-square test was used to analyze differences in the incidence of metabolic disorders between subjects with and without gallstone disease.

RESULTS: A total of 3573 people were included, 10.7% (384/3573) of whom had gallstone diseases. Multiple logistic regression analysis indicated that the incidence of gallstone disease in subjects aged 40-64 or ≥ 65 years was significantly different from that in those aged 18-39 years (P < 0.05); the incidence was higher in women than in men (P < 0.05). In men, a high level of fasting plasma glucose was obvious in gallstone disease (P < 0.05), and in women, hypertriglyceridemia or obesity were significant in gallstone disease (P < 0.05).

CONCLUSION: We assume that age and sex are profoundly associated with the incidence of gallstone disease; the metabolic risk factors for gallstone disease were different between men and women.

Insulin resistance and incident gallbladder disease in pregnancy

BACKGROUND & AIMS

Insulin resistance is associated with prevalent gallstones, but its effect on initial gallstone formation is not well-understood.

METHODS

We conducted a nested case-control study to examine whether insulin resistance is a risk factor for initial gallbladder sludge and stone formation during pregnancy. Cases were 205 women with new gallbladder sludge and stones during pregnancy and the early postpartum. Controls were 443 randomly selected women without sludge or stones during pregnancy. Gallbladder ultrasounds were obtained during each trimester and at 4-6 weeks post partum. Fasting serum glucose, lipids, and insulin were measured at 26-28 weeks gestation. Insulin resistance was measured by the homeostasis model. Logistic regression was used to identify independent risk factors for gallstone formation.

RESULTS

Insulin resistance was significantly greater in cases than in controls on univariate analysis (P < .001). Pre-pregnancy body mass index was strongly associated with gallstone formation on univariate analysis (P < .001), but this association was diminished after adjusting for insulin resistance (P = .01). On multivariate analysis, insulin resistance was significantly associated with gallstone formation (P = .004), even after adjustment for pre-pregnancy body mass index and other confounding factors including high-density lipoprotein cholesterol and physical activity. This association was strongest in women with pre-pregnancy body mass index <30 kg/m(2).

CONCLUSIONS

Insulin resistance is a risk factor for incident gallbladder sludge and stones during pregnancy, even after adjustment for body mass index. Insulin resistance might represent a causal link between obesity and overweight and gallstones.

Leptin regulates gallbladder genes related to absorption and secretion

Dysregulation of gallbladder ion and water absorption and/or secretion has been linked to cholesterol crystal and gallstone formation. We have recently demonstrated that obese, leptin-deficient (Lep(ob)) mice have enlarged gallbladder volumes and decreased gallbladder contractility and that leptin administration to these mice normalizes gallbladder function. However, the effect of leptin on gallbladder absorption/secretion is not known. Therefore, we sought to determine whether leptin would alter the expression of genes involved in water and ion transport across the gallbladder epithelium. Affymetrix oligonucleotide microarrays representing 39,000 transcripts were used to compare gallbladder gene-expression profiles from 12-wk-old control saline-treated Lep(ob) and from leptin-treated Lep(ob) female mice. Leptin administration to Lep(ob) mice decreased gallbladder volume, bile sodium concentration, and pH. Leptin repletion upregulated the expression of aquaporin 1 water channel by 1.3-fold and downregulated aquaporin 4 by 2.3-fold. A number of genes involved in sodium transport were also influenced by leptin replacement. Epithelial sodium channel-alpha and sodium hydrogen exchangers 1 and 3 were moderately downregulated by 2.0-, 1.6-, and 1.3-fold, respectively. Carbonic anhydrase-IV, which plays a role in the acidification of bile, was upregulated 3.7-fold. In addition, a number of inflammatory cytokines that are known to influence gallbladder epithelial cell absorption and secretion were upregulated. Thus leptin, an adipocyte-derived cytokine involved with satiety and energy balance, influences gallbladder bile volume, sodium, and pH as well as multiple inflammatory cytokine genes and genes related to water, sodium, chloride, and bicarbonate transport.

Insulin resistance causes human gallbladder dysmotility

Obesity, diabetes, and hyperlipidemia are known risk factors for the development of gallstones. A growing body of animal and human data has correlated insulin resistance with organ dysfunction. The relationship among obesity, diabetes, hyperlipidemia, and abnormal gallbladder motility remains unclear. Therefore, we designed a study to investigate the association among obesity, insulin resistance, hyperlipidemia, and gallbladder dysmotility. One hundred ninety-two healthy adult nondiabetic volunteers were studied. Gallbladder ultrasounds were performed before and after a standardized fatty meal. A gallbladder ejection fraction (EF) was calculated, and an EF of < 25% was considered abnormal. Serum was analyzed for cholesterol, triglycerides, cholecystokinin, leptin, glucose, and insulin. The homeostasis assessment model (HOMA) was used to determine insulin resistance. The volunteers had a mean age of 38 years (range, 18-77), and 55% were female. Thirty subjects (15%) had gallstones and were excluded from the study. Thirty subjects (19%) had abnormal gallbladder motility (EF < 25%). In lean subjects (n = 96) fasting glucose was significantly increased in the 16 subjects with gallbladder EF < 25% versus the 80 subjects with gallbladder EF > 25% (109 +/- 20 mg/dl versus 78 +/- 2 mg/dl, P < 0.05). Similarly, the HOMA index was significantly greater in subjects with gallbladder EF < 25% versus gallbladder EF >25% (3.3 +/- 1.2 versus 2.0 +/- 0.2, P < 0.05). In obese subjects (n = 66), fasting glucose, insulin, and insulin resistance were not associated with a gallbladder EF < 25%. These data suggest that in lean, nondiabetic volunteers without gallstones, gallbladder dysmotility is associated with an elevated fasting glucose as well as a high index of insulin resistance. We conclude that insulin resistance alone may be responsible for gallbladder dysmotility that may result in acalculous cholecystitis or gallstone formation.

Hyperleptinaemia and hypoadiponectinaemia are associated with gallstone disease

BACKGROUND

Gallstone disease has been regarded as an obesity-related disease. Therefore, we hypothesized that leptin and adiponectin, mainly produced by adipose tissue, may play roles in gallstone disease.

PATIENTS AND METHODS

The RIA method was used to analyze serum leptin and adiponectin levels of 90 gallstone patients and 91 healthy subjects.

RESULTS

Our results showed that BMI, fasting glucose, serum AST and ALT, and leptin were significantly increased in the gallstone patients as compared with the healthy subjects (P < 0.001, P < 0.001, P < 0.001, P < 0.001, P < 0.001, and P = 0.013, respectively). Intriguingly, serum adiponectin was the only variable to be significantly decreased in the gallstone patients (P = 0.002). Furthermore, serum AST, leptin, and adiponectin were significantly associated with gallstone disease (P < 0.001, P = 0.021, and P = 0.006, respectively). Overweight (BMI >or= 25 kg m(-2)), but not normal-weight, gallstone patients had an increased serum leptin and a decreased serum adiponectin level as compared with matched healthy subjects (P < 0.001 and P = 0.024, respectively). In addition, serum leptin was positively correlated with BMI and serum cholesterol, while serum adiponectin was inversely correlated with serum triglyceride in the gallstone patients.

CONCLUSIONS

Our study indicated that hyperleptinaemia and hypoadiponectinaemia might be involved in the occurrence of gallstone disease. However, the causal relationship of hyperleptinaemia and hypoadiponectinaemia with gallstone disease might require further investigation.

Ciliary neurotrophic factor restores gallbladder contractility in leptin-resistant obese diabetic mice

BACKGROUND

Obesity and diabetes are major risk factors for cholesterol gallstones, and the majority of obese people are leptin-resistant. Our previous work has shown that both leptin-deficient (Lepob) and leptin-resistant (Lepdb) obese diabetic mice have decreased in vitro gallbladder motility. Leptin administration to leptin-deficient (Lepob) animals restores gallbladder motility and reverses obesity and hyperinsulinemia. However, additional leptin in leptin-resistant obesity would not be expected to improve obesity-related parameters. Recent studies demonstrate that ciliary neurotrophic factor (CNTF) reduces weight and hyperinsulinemia in leptin-resistant obesity. Our hypothesis is that CNFT would cause weight loss, lower blood sugars, and restore gallbladder contractility in leptin-resistant (Lepdb) mice.

MATERIALS AND METHODS

20 C57b/6J and 20 Lepdb 8-week-old female mice were injected daily with either intraperitoneal saline or 0.3 microg/g CNTFAx15 for 17 days. Gallbladders were mounted in muscle baths and stimulated with acetylcholine, neuropeptide Y, and cholecystokinin. Gallbladder volume, serum glucose, insulin, liver weight, liver fat, and gallbladder responses were measured. Data were analyzed by ANOVA.

RESULTS

Saline treated obese mice had greater body weight and obesity parameters, but decreased gallbladder contractility to neurotransmitters compared to saline treated lean mice. CNTF administration to obese mice decreased body weight and obesity parameters, and restored gallbladder contractility. CNTF treated lean animals had weight loss and decreased gallbladder contraction to acetylcholine and cholecystokinin compared to saline treated lean animals.

CONCLUSIONS

Ciliary neurotrophic factor (CNTF) causes 1) weight loss, 2) improvement of diabetes, and 3) alterations in gallbladder motility that is improved in obese mice but decreased in lean mice. We conclude that CNTF may improve gallbladder contractility in leptin-resistant obesity with diabetes.

Diminished gallbladder motility in Rotund leptin-resistant obese mice

BACKGROUND

Obesity is a risk factor for cholesterol gallstone formation, but the pathogenesis of this phenomenon remains unclear. Most human obesity is associated with diabetes and leptin-resistance. Previous studies from this laboratory have demonstrated that diabetic leptin-resistant (Lep(db)) obese mice have low biliary cholesterol saturation indices, enlarged gallbladders and diminished gallbladder response to neurotransmitters. Recently, a novel leptin-resistant mouse strain Lepr(db-rtnd) (Rotund) has been discovered. Rotund mice are also obese, diabetic, and have an abnormal leptin receptor. Therefore, we tested the hypothesis that leptin-resistant obese Rotund mice would have large gallbladders and reduced biliary motility.

METHODS

Eight-week-old control (C57BL/6J, N=12) and Rotund leptin-resistant (Lepr(db-rnd), N=9) mice were fed a non- lithogenic diet for four weeks. Animals were fasted and underwent cholecystectomy. Gallbladder volumes were recorded, and contractile responses (N/cm(2)) to acetylcholine (10(-5) M), Neuropeptide Y (10(-8,-7,-6) M), and cholecystokinin (10(-10,-9,-8,-7) M) were measured. Results were analyzed using the Mann-Whitney Rank Sum Test.

RESULTS

Compared to control mice, Rotund mice had larger body weights, higher serum glucose levels, and greater gallbladder volumes (p<0.05). Rotund gallbladders had less contractility (p<0.05)) to acetylcholine and cholecystokinin than control mice. Responses to Neuropeptide Y were also less, but not statistically significant, in the Rotund mice.

CONCLUSIONS

These data suggest that leptin-resistant Rotund mice have (1) enlarged gallbladders with (2) diminished contractility compared to lean control mice. Therefore, this study confirms that leptin-resistance is associated with abnormal biliary motility and may lead to gallstone formation in leptin-resistant obesity.