Effects of SF-482 on bile, gallstones formation and experimental hyperlipemias

The effects of 3 alpha, 7 beta-dihydroxy-12-cheto-cholan-24-oic acid (SF-482) were compared with those of ursodeoxycholic acid on bile flow and composition, on gallstones formation and on experimental hyperlipemias. SF-482, like ursodeoxycholic acid, increases the bile flow and residue in normal and ethynylestradiol-treated rats. The two compounds increase the biliary excretion of bile acids and phospholipids with a desaturation of bile cholesterol. SF-482 and ursodeoxycholic acid decrease the incidence of gallstones in mice; both compounds are active in Triton WR-1339, in olive oil and margarine hyperlipemias in rats and in ethanol intoxication in mice. In general, SF-482 is more active than ursodeoxycholic acid.

Alcohol protects against cholesterol gallstone formation

Epidemiologic studies have suggested that alcohol intake may protect against cholelithiasis. Gallstone formation was studied in 20 prairie dogs fed a 0.4% cholesterol-supplemented liquid diet. In ten animals, ethanol provided 35% of total calories. In ten pair-fed controls, ethanol was replaced with isocaloric maltose. After 3 months the gallbladders were inspected for gallstones, and gallbladder bile was analyzed. Cholesterol macroaggregates were present in all controls and pigment concretions were noted in five. No stones were observed in ethanol-fed animals. Bile in the ethanol group contained less cholesterol than the controls (5.60 +/- 0.71 vs. 9.16 +/- 0.61 mmol/L, p less than 0.05) while phospholipids, total bile acids, and bilirubin were unchanged. The resulting cholesterol saturation index was reduced in the ethanol group (0.81 vs. 1.22, p less than 0.05). The ratios of trihydroxy to dihydroxy bile acids were also different (2.07 +/- 0.25 in ETOH vs. 3.29 in controls, p less than 0.05). The bile calcium concentration was higher in control animals presumably secondary to the use of complex sugars (5.36 +/- 0.37 vs. 3.77 +/- 0.32 mmol/L, p less than 0.05). These results confirm that ethanol inhibits cholesterol gallstone formation. They further suggest that this effect is dependent on reductions of biliary cholesterol and selective changes in bile acid concentrations.

The case for prophylactic cholecystectomy concomitant with gastric restriction for morbid obesity

The pre and postoperative incidence of cholelithiasis were investigated in patients undergoing bariatric surgery at the University of Florida. The first part of the study was retrospective and revealed a pre and 24-month postoperative incidence of cholelithiasis of 30 and 40 percent respectively. Age and postoperative interval were not predictive of cholelithiasis. Patients with cholelithiasis had a significantly greater weight loss (130 +/- 61.0 lbs) than those without stones (109 +/- 59.9 lbs) P = 0.04. Men had a significantly greater weight loss than women (160 +/- 15 lbs SEM versus 99 +/- 7 lbs SEM) as well as a higher incidence of cholelithiasis (53 and 24%, respectively). In the second, prospective part of the study, cholecystectomy was performed in 73 consecutive patients concomitant with their bariatric procedure. Ninety six per cent of removed gallbladders had gross or histologic abnormalities including cholelithiasis in 27 per cent and cholesterolosis/cholecystitis in 69 per cent. The incidence of cholelithiasis was higher than that found in the retrospective series by preoperative ultrasound. The bariatric surgical patient is clearly at risk for the development of postoperative cholelithiasis and cholecystitis. The risk appears to be related to the amount of weight loss. In addition, some gallstones may remain undetected at the time of surgery. We therefore recommend prophylactic cholecystectomy at the time of bariatric surgery.

The prevention of experimental cholesterol gallstones by ileectomy in mice

After a lithogenic diet containing 0.5 per cent cholesterol and 0.25 per cent sodium cholate was fed to a group of normal Crj-ICR male mice for 10 days, cholesterol gallstones developed. No formation of gallstones occurred, however, in a group of mice from which 20 cms of terminal ileum had been removed prior to the feeding of the lithogenic diet. The biliary concentrations of cholesterol, phospholipids and bile acids were markedly lower in the ileectomized mice, with the decrease in cholesterol concentration being most significant. On the other hand, fecal excretion of sterols and bile acids increased in the ileectomized mice. The pool size of bile acids increased after the feeding of the lithogenic diet, but ileectomy decreased the pool size in mice fed the ordinary or lithogenic diets. The biliary concentration of cholic acid increased after the feeding of the lithogenic diet, but decreased with ileectomy. The biliary concentration and fecal excretion of deoxycholic acid markedly increased, while those of beta-muricholic acid and its secondary bile acids, omega-muricholic acid and hyodeoxycholic acid, decreased. The increase in plasma and liver cholesterol levels after the feeding of the lithogenic diet was prevented by ileectomy. These data suggest that ileectomy prevents the formation of cholesterol gallstones after the feeding of a lithogenic diet due to a decrease in cholic acid absorption.

Spontaneous passage of glass beads from the canine gallbladder: facilitation by sphincterotomy

To investigate the mechanism by which ablation of the sphincter of Oddi prevents gallstone formation, we assessed passage of glass beads out of the gallbladders of dogs with sphincterotomy and sham sphincterotomy. One month after bead implantation, dogs with an intact sphincter passed 52%, 26%, 22%, 10%, 0%, and 0% of beads with diameters of 2, 3, 4, 5, 6, and 8 mm, respectively. For the same respective bead diameters, dogs with a sphincterotomy passed 90%, 90%, 88%, 75%, 75%, and 42% of beads (p less than 0.05 for all bead diameters). No beads were in the common bile duct of any dog. In separate dogs studied by cholescintigraphy, sphincterotomy significantly increased gallbladder ejection fraction from 0.46 to 0.76 (p less than 0.01). In addition, sphincterotomy significantly lowered resting gallbladder volume from 24.4 to 15.8 ml (p less than 0.025) and lowered cholecystokinin-stimulated gallbladder volume from 13.3 to 5.9 ml (p less than 0.025). These data indicate that even with an intact sphincter, small solids can pass from the gallbladder and into the duodenum. Sphincterotomy facilitates passage of solids, apparently by general improvement in gallbladder emptying. Facilitated passage of crystals, microliths, or small stones seems the most likely explanation for prevention of gallstone formation by sphincterotomy.

Long-term occlusion of the porcine cystic duct by means of endoluminal radio-frequency electrocoagulation

Recurrent cholelithiasis must be expected after gallstone removal without cholecystectomy. Chemical gallbladder ablation may offer prevention but requires preliminary cystic duct occlusion. Radio-frequency (RF) electrocoagulation of the cystic duct was performed in 15 pigs to induce occlusion by a controlled thermal epithelial injury. A flexible coagulation catheter was placed into the cystic duct lumen under fluoroscopic control by means of either subhepatic cholecystostomy or direct, percutaneous transhepatic gallbladder puncture. Complete cystic duct occlusion was proved in 14 animals. Follow-up ranged from 1 to 17 weeks (mean, 11 weeks). Histologically, the RF technique induced an intense chronic inflammatory and fibroblastic reaction, which eventually obliterated the coagulated cystic duct segments. There was no epithelial regeneration or recanalization of the fibrotic cystic duct segments. The adjacent structures, particularly the cystic artery, were intact in all specimens.

Dissolution of cholesterol gallstones by bile acids in the prairie dog

The effect of chenodeoxycholic acid, ursodeoxycholic acid and hyodeoxycholic acid on gallstone dissolution was studied in the prairie dog. Cholesterol gallstones were found in all animals after feeding a semipurified diet plus 1.2% cholesterol for six wk. Gallstone regression was examined by feeding a chow diet containing the bile acids (chenodeoxycholic acid, ursodeoxycholic acid or hyodeoxycholic acid) alone (30 mg/kg/day) or in combination (chenodeoxycholic acid plus ursodeoxycholic acid) for an additional six wk. Chenodeoxycholic acid was effective in dissolving established cholesterol gallstones (two out of 16 animals still had stones) and cholesterol crystals (six out of 16 animals had crystals); the hydrophilic bile acids, ursodeoxycholic acid and hyodeoxycholic acid, were ineffective in the six-wk regression study. The lithogenic indices averaged 1.09 at the end of the induction period; all biles became unsaturated with respect to cholesterol after the six-wk regression period (group 1, 0.82; group 2, 0.66; group 3, 0.81; group 4, 0.84; group 5, 0.66). Cholesterol levels in liver, plasma and bile were elevated after the six-wk induction phase (4.59 mg/g, 610 mg/dl and 0.36 mg/ml, respectively) but returned to near normal levels after the six-wk regression period. Biliary bile acids contained increased levels of the dietary bile acid administered to each group. This experiment shows that relatively hydrophobic bile acids may be more effective than hydrophilic bile acids for gallstone dissolution during the period studied.

Influence of N,N'-(1,11-undecandiyl) bis (2,3-dihydro-2-methyl-1H-indole-1-carboxamide) (BAY 02752) on gallstone formation and regression in hamsters

A new hypolipidemic drug (BAY 02752) when added to a lithogenic hamster diet at dosages of 1000 and 500 mg per kg of diet significantly (p less than 0.005) inhibited gallstone formation. When BAY 02752 was fed to hamsters with pre-established gallstones, it inhibited progression (p=0.052) of the stones and appeared to promote dissolution.

Absorption of biliary calcium from the canine gallbladder: protection against the formation of calcium-containing gallstones

Calcium salts are the major components of pigment gallstones. The calcium species in bile that is critical for Ca++ precipitation is free ionized calcium, [Ca++]. Factors that regulate biliary [Ca++] in bile are therefore of great importance in the pathogenesis of pigment gallstones. The fate of biliary Ca++ on entry into the gallbladder has not previously been studied. We here report that a minimum of 51.3% +/- 8.8% (SEM) of Ca++ is absorbed from the canine gallbladder on concentration of bile during a 24-hour fast. In addition, there was absorption of least 70.9% +/- 6.2% of Na+, 56.5% +/- 8.6% of K+, and nearly all (greater than 98%) of Cl-. Absorption, neutralization, or both, of HCO3- was also nearly complete (greater than 98%). During concentration of bile by the gallbladder, the concentrations of all biliary cations increased as total bile salt concentration increased, whereas anion concentrations declined. These results are consistent with a Gibbs-Donnan effect induced by impermeable, negatively charged bile salt molecules. Comparison of bile/plasma [Ca++] ratios with those for [K+], a passively distributed ion, was also consistent with, although not proof of, the passive absorption and distribution of Ca++ across the gallbladder epithelium. The absorption of Ca++ by the gallbladder may be a factor in the prevention of pigment gallstones, because it limits free Ca++ ion in bile, and thus decreases the likelihood of precipitation of calcium.

The role of dietary fiber in gastrointestinal disease

The most consistent benefit of consumption of adequate dietary fiber is regular laxation; this effect alone justifies inclusion of fiber in the diet, in view of the enormous expenditure on drugs for digestive diseases. Dietary fiber has proved effective in decreasing symptoms of diverticular disease, Crohn's disease, and hemorrhoids in a limited number of small clinical studies. Fiber may also reduce the incidence of gallstone formation. Fiber is currently being touted as protection against colon cancer. However, the epidemiological and experimental data do not provide convincing evidence that fiber alone is a major determinant of risk for colon cancer. Furthermore, the data from international comparisons indicating that fiber is protective against colon cancer can be used in a similar simplistic manner to suggest that fiber may be a risk factor for stomach cancer. This should not dissuade individuals from obtaining adequate fiber from a wide variety of foods but should caution them against consumption of excessive amounts of fiber from a single source or from dietary supplements.

[Role of modern diet therapy in the prevention of visceral complications in patients with dietary obesity]

The examination and treatment of 547 patients with alimentary obesity revealed in them significant impairments of myocardial contractility, manifest hemodynamic disorders (in 65.5% of patients), marked changes in lipid metabolism (hypercholesterolemia, hypertriglyceridemia, hyperlipacidemia, hyperlipoproteinemia type IIa in 26,5%, type IIb in 14,5%, type IV in 32,5% of patients), as well as reduced activity of the T-immunity system, all these changes being prerequisites for the development of atherosclerosis, ischemic heart disease and essential hypertension. During examination of the patients' liver, fatty hepatosis was detected in 91.4%, chronic nonalcoholic steatohepatitis in 14% of patients, manifest shifts were found in their bile biochemical composition, leading to the development of cholelithiasis. The incretory dysfunction of the pancreas led to carbohydrate imbalance in 43%, and to diabetes mellitus in 7.5% of patients. Under the effect of the treatment (diet, exercise therapy, oxygenotherapy, hydrotherapy) conducted in the alimentary obesity patients, lessening of the pathologic process was observed in the heart, liver and pancreas, their functions being significantly improved. It has been concluded that normalization of the body weight in obese subjects is a measure preventing atherosclerosis, ischemic heart disease, essential hypertension, fatty hepatosis, steatohepatitis, cholelithiasis and diabetes mellitus.