Limits and perspective of oral therapy with statins and aspirin for the prevention of symptomatic cholesterol gallstone disease

The prevalence of gallstones disease in Western countries is 10 - 15%. Gallstones can be one of two types - cholesterol or pigment - with cholesterol gallstones representing nearly the 80% of the total. Cholesterol and pigment gallstones have different predisposing factors: cholesterol gallstones are related to supersaturated bile in cholesterol, whereas black pigment gallstones are related to hyperbilirubinbilia factors (hemolysis, etc.); these are necessary, but not sufficient, factors to produce gallstones in vivo. Gall bladder mucosa factors (gall bladder secretion of mucin, local bile stasis and production of endogenous biliary β-glucuronidase) may coexist with the aforementioned factors and facilitate gallstone nucleation and growth. The gold-standard treatment for symptomatic gallstones is laparoscopic cholecystectomy. Several studies have reported a significant reduction in the onset of symptomatic gallstones disease in patients undergoing chronic therapy with statins, which can reduce bile cholesterol saturation. Aspirin, which has been shown to reduce the local production of gall bladder mucins (mucosal or parietal factors of gallstone formation) in animal experimental models, does not appear to reduce the risk of symptomatic gallstones disease when tested alone. The new horizon of oral therapy for the prevention of symptomatic gallstone disease needs to evaluate the long-term effect of statins and chronic aspirin administration in patients with dyslipidemia and/or atherosclerosis.     

A practical guide to the nonsurgical treatment of gallstones.

Until recently, cholecystectomy was the only treatment available for symptomatic gallstone disease. During the past 20 years, better understanding of the pathogenesis of cholesterol gallstone disease has led to alternative nonsurgical methods for treating gallstones in selected groups of patients. Use of 2 naturally occurring bile acids, chenodeoxycholic acid (CDCA) and ursodeoxycholic acid (UDCA), was reported in 1972 and 1975, respectively, for successful dissolution of cholesterol gallstones in humans. Both these bile acids act by reducing cholesterol secretion in bile, thus enabling it to solubilise more cholesterol from the stone surface. Micellar solubilisation is involved, together with liquid crystal formation in the case of UDCA. Having been extensively studied in clinical trials to assess efficacy and safety, both these compounds are now available for general use. The efficacy of CDCA can be enhanced by single bedtime dose administration and by taking a low cholesterol diet. Bedtime administration also enhances the effect of a suboptimal dose of UDCA. CDCA induces dose-related diarrhoea and hypertransaminaemia, and UDCA can induce calcification of gallstones, thus rendering them resistant to medical dissolution. A combination of the 2 bile acids at half the recommended dose for each has become an accepted practice for reducing adverse effects, and this may also enhance efficacy. One of the main problems of bile acid therapy is that dissolution of gallstones is a very slow process. Use of extracorporeal shockwave lithotripsy (ESWL) to break the stones into smaller fragments, with concurrent use of bile acids, has been shown to speed dissolution rate and to achieve complete gallstone dissolution in 78% of selected cases within 12 months.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of sodium acetyl salicylate on cholesterol saturation of fasting gall bladder bile, with and without chenic acid.

The aims of this study were (a) to determine whether sodium acetyl salicylate by itself or in combination with chenodeoxycholic (chenic) acid would decrease the cholesterol saturation index (SI) of fasting gall bladder bile in man; and (b) to confirm prospectively that 8 mg kg-1 day-1 chenic acid given at bedtime together with a low cholesterol diet reduces gall bladder bile SI to a level where consistent gallstone dissolution would be expected. Seven patients were studied on each of the following regimens given in random order for 1 month each: bedtime chenic acid alone 8 mg kg-1 day-1; sodium acetyl salicylate alone 600 mg four times daily; bedtime chenic acid together with sodium acetyl salicylate; no treatment. Gall bladder samples were taken by nasoduodenal intubation at the end of each regimen and SI determined. SI (mean +/- s.e. mean) on low cholesterol diet with no drug treatment was 1.14 +/- 0.06. On bedtime chenic acid 8 mg kg-1 day-1 plus low cholesterol diet it fell to 0.83 +/- 0.03 (P less than 0.05). Sodium acetyl salicylate did not alter gall bladder bile SI. 95% confidence limits for the effect of sodium acetyl salicylate on SI were +0.03 and -0.05. We conclude that (a) sodium acetyl salicylate does not lower SI of gall bladder bile in man; (b) an adequate fall in SI for gallstone dissolution can be achieved with a reduced dose (8 mg kg-1 day-1) of chenic acid given at bedtime with a low cholesterol diet.     

Drugs affecting biliary lipid secretion and gallbladder motility: their potential role in gallstone treatment and prevention

Gallstone disease in the Western world has an estimated prevalence of 10-15% and more than 75% are cholesterol-enriched gallstones. Defective gallbladder motility has been identified as an important pathogenic factor for cholesterol gallstone disease. Various agents may enhance or impair postprandial gallbladder motility, and their effects on interdigestive gallbladder and intestinal motility should also be taken into account. Patients in high-risk situations for gallstone disease, and those chronically treated with drugs inhibiting gallbladder motility (e.g. somatostatin analogues) may benefit from improving gallbladder motility with prokinetic agents. Whether such a strategy can really prevent gallstone formation is still unknown, long-term studies are lacking so far. The efficacy of bile acid therapy with UDCA for gallstone dissolution or for prevention in high risk patients is limited and hampered by high recurrence rates. The efficacy of UDCA in prevention of colics or gallstone related complications in symptomatic patients with gallbladder stones with contraindications for operation or on the waiting list should be explored further, since several retrospective studies showed favourable outcomes with this strategy.     

Effects of leptin on biliary lipids: potential consequences for gallstone formation and therapy in obesity

Gallstone disease is exceptionally common, occurring especially in Western populations, with cholesterol gallstones predominating. Currently, it is believed that obesity is the most consistent and important risk factor for the development of cholesterol gallstones. Obesity has been shown to be associated with the supersaturation of bile with cholesterol because of increased hepatic secretion of the sterol. In accord with current information from experimental studies, leptin appears to be involved in biliary cholesterol secretion and cholesterol gallstone formation in humans. This review summarizes the current information on the role of obesity in biliary lipid secretion as well as the effect of leptin and its potential consequences for gallstone formation and therapy in the obese.     

The genetic background of cholesterol gallstone formation: an inventory of human lithogenic genes

Family and twin studies as well as animal studies indicate that gallstone disease is, in part, genetically determined. Recently new single gene defects have been identified in specific patients with cholesterol and pigment gallstones. Examples include low phospholipid-associated cholelithiasis due to mutations of the gene encoding the hepatocanalicular phosphatidylcholine transporter, and pigment stones in association with mutations of the ileal bile salt transporter gene. Here we summarize the evidence for common genetic determinants of human gallstone disease in general and provide an inventory of human lithogenic genes. The precise understanding of such genes and their molecular mechanisms will establish new targets for rational drugdesign for this exceptionally prevalent and economically significant digestive disease.     

New targets in and potential treatments for cholesterol gallstone disease

Gallstone disease is very common among American Indians and Hispanics, and approximately 20 million patients are treated for this disease annually in the US. Bile acid receptor (nuclear farnesoid X receptor; FXR) knockout mice fed a lithogenic diet are more susceptible to gallstone disease than wild-type mice. The C57L mouse is also susceptible to gallstone formation when fed a lithogenic diet, and in this model, the small-molecule FXR agonist GW-4064 prevents the precipitation of cholesterol. Bile acids (eg, P-muricholic acid) and their derivatives are also being developed as FXR agonists. Fatty acid bile acid conjugates have the potential to prevent and reverse cholesterol crystallization. Furthermore, agents that increase the expression of selected hepatocyte bile acid transporters may also be useful in the treatment of gall bladder disease.     

Pathobiology of cholesterol gallstone disease: from equilibrium ternary phase diagram to agents preventing cholesterol crystallization and stone formation

The primum movens in cholesterol gallstone formation is hypersecretion of hepatic cholesterol, chronic surpersaturation of bile with cholesterol and rapid precipitation of cholesterol crystals in the gallbladder from cholesterol-enriched vesicles. Associated events include biochemical defects (increased biliary mucin, and increased proportions of hydrophobic bile salts in the intestine and gallbladder), motility defects (gallbladder smooth muscle hypocontractility in vitro and gallbladder stasis in vivo, sluggish intestinal transit), and an abnormal genetic background. The study of physical-chemical factors and pathways leading to cholesterol crystallization in bile has clinical relevance and the task can be carried out in different ways. The lithogenicity of bile is investigated in artificial model biles made by three biliary lipids - cholesterol, bile salts and phospholipids - variably combined in systems plotting within the equilibrium ternary phase diagram; also, crystallization propensity of ex vivo incubated human bile is studied by biochemical analysis of precipitated crystals, polarizing quantitative light microscopy and turbidimetric methods. The present review will focus on the recent advances in the field of pathobiology of cholesterol gallstones, by underscoring the role of early events like water transport, lipid transport, crystallization phenomena - including a genetic background - in gallstone pathogenesis. Agents delaying or preventing precipitation of cholesterol crystals and gallstone formation in bile will also be discussed.     

Medical management of cholesterol gallstones

Cholesterol gallstones are a significant cause of morbidity in the U.S. Methods used to treat gallstones include cholecystectomy or medical dissolution. The primary drugs used for the dissolution of cholesterol gallstones are two bile acids, chenodeoxycholic acid and ursodeoxycholic acid. Complete or partial gallstone dissolution rates using chenodeoxycholic acid have ranged from 30 to 80 percent. Factors affecting gallstone dissolution using the bile acids include the dosage and administration schedule, obesity, the stone characteristics, diet, and the duration of therapy. The adverse effects of chenodeoxycholic acid include gastrointestinal complaints, hepatotoxicity, and increased serum cholesterol. Ursodeoxycholic acid, which is investigational, differs from chenodeoxycholic acid in its mechanism of action. Ursodeoxycholic acid has similar efficacy with chenodeoxycholic acid, at a lower daily dosage, with less gastrointestinal and hepatic adverse effects. If appropriate patient selection is used, the response rate to medical therapy can range from 50 to 80 percent.     

Effect of Larrea tridentata (creosote bush) on cholesterol gallstones and bile secretion in hamsters

Larrea tridentata (Sesse and Moc. ex DC.) Coville is used for the treatment of gallstones in traditional Mexican medicine. The possible prevention or elimination of gallstones by ethanolic and aqueous extracts of the leaves and twigs of L. tridentata was tested in hamsters fed a rich carbohydrate, fat-free diet. In addition, the effects of the ethanolic extract and its main metabolite, nordihydroguaiaretic acid, on bile secretion in the perfused liver were tested. In the experiment on prevention of gallstones, the dry ethanolic extract at a level of 0.5% of diet completely inhibited gallstone formation, lowered biliary moles percent cholesterol and increased the proportion of chenodeoxycholic acid of hepatic bile. The dry aqueous extract at a level of 1% of diet did not affect gallstone frequency or biliary parameters. In the experiment on elimination of gallstones, the ethanolic extract significantly reduced gallstone frequency, gallbladder bile cholesterol concentration and moles percent cholesterol. Both the ethanolic extract and nordihydroguaiaretic acid had cholestatic effects in the perfused liver, with an EC50 of 34 and 28 mg dL-1, respectively, when perfused for 10 min. This effect was reversible with concentrations up to 40 mg dL-1. The results indicate that L. tridentata could be useful in the treatment of gallstone disease, however care must be taken due to its hepatotoxicity.     

Statins as potential treatment for cholesterol gallstones: an attempt to understand the underlying mechanism of actions

INTRODUCTION: Statin therapy is widely used across the globe for the treatment and prevention of cardiovascular disease (CVD). It is well established that statin therapy is associated with significant decreases in low-density lipoprotein cholesterol (LDL-C) and plasma cholesterol levels. Cholesterol gallstones are a common problem, resulting in hospital admission and surgery, throughout western healthcare systems. AREAS COVERED: This review describes the mechanisms, and addresses the potential, for statins to be used as a treatment for gallstones. Medline was searched for the risk factors and treatment of cholesterol gallstones. EXPERT OPINION: Obesity, metabolic syndrome, non-alcoholic fatty liver disease (NAFLD), insulin resistance and high-fat diets (unsaturated fats) rich in cholesterol are all associated risk factors for cholesterol gallstones. In view of the high prevalence of cholesterol gallstones, there is an urgent need to understand whether pharmacological therapies can be harnessed for the treatment of cholesterol gallstones. Gallstones are shown to be associated with an increased risk, not only of mortality, but also of CVD. Statins, widely used in prevention of CVD and hypercholesteremia, have been shown to dissolve cholesterol gallstones in animal models and human studies, highlighting the potential for a pharmacological therapy for gallstones. More studies are required to understand the role of statins in the treatment of gallstones and for comparison with current treatment strategies.     

Free fatty acids in gallstones in mice fed a diet containing cholic acid

In mice, combined addition of 1% cholesterol and 0.5% cholic acid to a diet induced cholesterol gallstones within 40 days as a result of the supersaturation of cholesterol in the bile, as has been reported. The major component of the gallstone was cholesterol, which was measured by HPLC. In this study, however, single addition of 1% cholic acid to a diet, which did not decrease cholesterol solubilizing capacity in bile, contributed to gallstone formation in mice within 50 days. The gallstones thus formed contained a large amount of palmitic acid. In the hepatic bile of this animal, palmitic acid was also detected; however, no solid material was observed by light and polarized-light microscopes. Free fatty acids such as palmitic acid seem to be dissolved in a complex micelle composed of bile acids and lecithin. This probably causes gallstone formation by reducing cholesterol solubilizing capacity in bile.     

Statins as potential treatment for cholesterol gallstones: an attempt to understand the underlying mechanism of actions

Introduction: Statin therapy is widely used across the globe for the treatment and prevention of cardiovascular disease (CVD). It is well established that statin therapy is associated with significant decreases in low-density lipoprotein cholesterol (LDL-C) and plasma cholesterol levels. Cholesterol gallstones are a common problem, resulting in hospital admission and surgery, throughout western healthcare systems.

Areas covered: This review describes the mechanisms, and addresses the potential, for statins to be used as a treatment for gallstones. Medline was searched for the risk factors and treatment of cholesterol gallstones.

Expert opinion: Obesity, metabolic syndrome, non-alcoholic fatty liver disease (NAFLD), insulin resistance and high-fat diets (unsaturated fats) rich in cholesterol are all associated risk factors for cholesterol gallstones. In view of the high prevalence of cholesterol gallstones, there is an urgent need to understand whether pharmacological therapies can be harnessed for the treatment of cholesterol gallstones. Gallstones are shown to be associated with an increased risk, not only of mortality, but also of CVD. Statins, widely used in prevention of CVD and hypercholesteremia, have been shown to dissolve cholesterol gallstones in animal models and human studies, highlighting the potential for a pharmacological therapy for gallstones. More studies are required to understand the role of statins in the treatment of gallstones and for comparison with current treatment strategies.     

Lipid lowering drugs and gallstones: a therapeutic option?

Cholelithiasis is a common disease worldwide. The majority of gallstones can occur when the bile is supersaturated with cholesterol. Dyslipidaemia, obesity, insulin resistance are associated with an increased risk for cholesterol gallstone formation as well as with vascular risk. Statins and ezetimibe are used to treat dyslipidaemia and appear to have some effect on bile composition and cholesterol gallstone formation. Statin (e.g. pravastatin, simvastatin, fluvastatin and lovastatin) monotherapy or combined with ursodeoxycholic acid (UDCA) have shown reductions in bile cholesterol saturation, preventing gallstone formation and even dissolving pre-existing stones. However, this effect was not consistently reported in all studies. Statin use has also been associated with a reduced risk for cholecystectomy in 2 large epidemiological studies. Ezetimibe was shown to have a beneficial action against cholelithiasis in animal studies but data in humans - although promising - are very limited. The effect of these drugs on gallstone disease warrants further investigation in large human trials. We also consider the links between cholelithiasis, vascular risk and the use of lipid lowering drugs.     

脂肪肝超声诊断与胆囊结石的相关性研究

目的 探讨脂肪肝和胆囊结石发病之间的关系.方法 结合本院超声检查的1165例患者,分别按照脂肪肝和胆囊结石的诊断标准,判断二者之间的发病情况.结果 经超声榆查出418例脂肪肝患者,89例非脂肪肝患者.脂肪肝患者胆囊结石的患病率(17.9％)明显高于非脂肪肝患者(6.8％).结论 脂肪肝与胆囊结石的关系密切.超声检查准确、有效,是检查脂肪肝和胆囊结石的重要途径,同时可加强脂肪肝疾病的预防,有效控制胆囊结石的发病率.     

Effects of fluvastatin on biliary lipids in subjects with an elevated cholesterol saturation index

OBJECTIVE: 3-Hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors have been suggested as agents to reduce the biliary cholesterol saturation index (CSI) in duodenal bile and therefore might be supportive in primary or secondary prevention of gallstones. However, the efficiency of the therapy seems to depend on both the HMG-CoA reductase inhibitor used and the study population selected. METHODS: We therefore investigated the effect of a high-dose application of fluvastatin on biliary lipid composition in 21 subjects exhibiting mild hypercholesterolaemia and a history of current gallstones or cholecystectomy due to gallstone disease. Subjects were treated either with 40 mg fluvastatin twice per day over a 3-month period (n = 14) or with placebo (n = 7). Bile samples were aspirated during endoscopy after intravenous ceruletid stimulation before and after therapy. RESULTS: Both groups were comparable in CSI (mean +/- SD) at baseline (1.78 +/- 0.2 placebo vs. 1.97 +/- 0.4 verum). CSI significantly decreased in the verum group to 1.45 +/- 0.4 (P = 0.003) mainly due to increased phospholipid levels, whereas no difference was observed in the placebo group (1.85 +/- 0.7, n.s.). In addition, the verum group exhibited a significant reduction of hydrophobic deoxycholic acid, which has been reported to induce cholesterol crystal precipitation, and an increase of hydrophilic cholic acid. CONCLUSION: Fluvastatin might decrease the risk of cholesterol gallstone formation in patients with elevated biliary CSI during long-term treatment by reduction of biliary cholesterol saturation and percentage change in deoxycholic acid content.     

老年胆石症的临床特点及外科诊疗研究

目的探讨老年胆囊结石换则的临床特点及外科诊断治疗。方法回顾性分析2006年1月至2009年4月50例老年胆囊结石患者的临床资料。结果术前充分准备,治疗基础疾病;急诊手术9例,择期手术41例,根据结石分布范围采用行单纯胆囊切除术39例、胆总管切开取石术加T管引流术7例、胆囊切除术胆总管切开取石术加T管引流术4例。全组患者均完成手术,术中无死亡;治愈49例,死亡1例,为急诊手术后感染中毒性休克死亡;手术并发症6例:呼吸道感染4例、切口裂开1例、泌尿系感染1例,经对症治疗治愈。住院11～34d,平均(15.9±4.5)d。结论老年人胆石症的外科治疗应针对老年人胆管疾病的特点,必须完善围手术期处理,选择合适的手术时机和手术方式,尽量避免急诊手术以提高手术治愈率,减少并发症的发生。     

生理性心脏起搏的临床应用

目的 探讨生理性心脏起搏的临床应用。方法 21例患者,男性14例,女性7例,年龄42－81岁。病态窦房结综合征10例,高度房室传导阻滞9例,三束支传导阻滞2例。植入DDDR8例,DDD10例,AAI1例,VVIR2例。结果 植入各种类型生理性起搏器占同期植入起搏器总数的50％,其中双腔起搏器占42．9％,频率适应性起搏器占23．8％,均经穿刺锁骨下静脉送入心房和／或心室电极,分别成功固定于右心耳或右室心尖部,测试起搏阈值、电极阻抗及P波或R波或R波振幅均较满意。结论 生理性心脏起搏符合生理需要,是较理想的起搏方式。     

Pharmacokinetics of cefepime in bile and gall bladder tissue after prophylactic administration in patients with extrahepatic biliary diseases

The purpose of this study was to determine the cefepime concentrations in serum, bile and gall bladder tissue after administration of a single dose in patients with extrahepatic biliary diseases for pre-operative antimicrobial prophylaxis. During a 3-year period (1999-2002), 30 patients aged above 18 years with extrahepatic biliary diseases (acute and chronic cholecystitis and symptomatic cholelithiasis) were included in the study. Cefepime concentrations were determined by the agar microbiological diffusion method. A significant correlation between serum and gall bladder tissue concentrations of cefepime with the sampling interval was observed (r2 = 0.771, P<0.0001), whereas no correlation between serum and bile fluid concentrations of the drug was noted. In patients with non-functioning gall bladder, very low tissue levels of cefepime were detected. During the time of surgery, serum and gall bladder tissue concentrations of cefepime exceeded the minimum inhibitory concentration for 90% of the organisms (MIC90) for most common pathogens. Cefepime has the required pharmacokinetic properties to be considered for pre-operative antimicrobial prophylaxis in patients undergoing biliary tract surgery.     

Bile composition in inflammatory bowel disease: ileal disease and colectomy,but not colitis,induce lithogenic bile

BACKGROUND: Inflammatory bowel disease is a risk factor for gall-bladder stones, but there is controversy about the composition of these stones and whether such patients develop lithogenic bile. METHODS: In 54 gallstone-free inflammatory bowel disease patients and 13 non-inflammatory bowel disease patients with cholesterol-rich gallstones, we measured the biliary cholesterol saturation indices, nucleation times and bilirubin concentrations, and determined the bile acid composition and molecular species of phosphatidylcholine, in gall-bladder bile. RESULTS: Patients with Crohn's colitis or ulcerative colitis had less saturated bile (mean cholesterol saturation index, 0.9) and longer nucleation times (median, 21 days) than those with ileal Crohn's disease (1.5; 14 days) or those who had undergone colectomy (1.6; 5 days). In patients with ileal Crohn's disease, the mean biliary bilirubin concentration was two- to three-fold higher than that in the other groups, and was associated with a decrease in the percentage of biliary deoxycholate and an increase in the percentage of ursodeoxycholate, compared with disease controls, but phosphatidylcholine species were similar. CONCLUSIONS: Patients with small bowel Crohn's disease, or who have undergone colonic resection, have supersaturated bile and an increased risk of cholesterol gallstone formation. In patients with ileal disease, the presence of high biliary bilirubin concentrations and low percentage of deoxycholic acid may also favour the formation of mixed, pigment-rich, gallstones.