Fecal Fat Content Research Articles

Comparative effect of amidated pectin and psyllium on cholesterol homeostasis in rats

AbstractThe effects of amidated pectin and psyllium on serum, hepatic and faecal cholesterol concentration were compared in female rats fed diets supplemented with palm fat and cholesterol at 50 and 10 g/kg, respectively. Control rats were fed a diet supplemented with cellulose at 60 g/kg. In treated rats, cellulose was replaced with either amidated pectin or psyllium. Amidated pectin and psyllium intake significantly decreased serum cholesterol from 3.41 μmol/ml (control) to 1.68 and 2.04 μmol/ml, respectively, and hepatic cholesterol from 31.9 μmol/g (control) to 7.2 and 9.0 μmol/g, respectively. Histology with lipid-staining Sudan Black B revealed that liver tissue from control rats was infiltrated with lipids, but staining was absent in livers of treated rats. No hepatic pathophysiology was apparent in treated rats. Amidated pectin and psyllium intake significantly increased faecal fat content. Faecal cholesterol content was significantly increased in rats that were fed amidated pectin, and non-significantly increased in rats that were fed psyllium. Body weight and food intake did not differ among treatment groups. In conclusion, amidated pectin, a novel sequestrant of sterols, demonstrated a similar effect on rat serum and hepatic cholesterol concentration to psyllium, which is a well-established hypocholesterolaemic agent.

Acid steatocrit determination is not helpful in cystic fibrosis patients without or with mild steatorrhea

Most methods used for the assessment of severe steatorrhea in cystic fibrosis (CF) are sensitive. In fact, the tests show their usefulness in a borderline zone of the results. Yet, the existing data related to acid steatocrit (AS) are still contradictory. Therefore, in the present study we have aimed to assess CF patients without or with mild steatorhea (<10 g/day) and evaluate the applicability of AS in such a subset of patients. In fifty-five CF patients, AS, fecal fat concentration (FFC) and fecal fat excretion (FFE) in 1-day stool collection were assessed from one to three times (149 samples). In 50 subjects, FFC, FFE, and AS were available for 3 subsequent days. It allowed for the calculations based upon 3-day fecal fat balance study. The correlations between FFE/FFC and AS based upon 1-day stool collection, although statistically significant, were rather weak (r = 0.208, P < 0.011; r = 0.362, P < 0.000006, respectively). The correlations between FFE/FFC and AS based upon the 3-day stool collection, although stronger, did not show values a linear relationship (r = 0.394, P < 0.005; r = 0.454, P < 0.001, respectively). With no regard to the cut-off level for AS (10% and 20%), sensitivity, specificity, negative, and positive predictive values in the determination of abnormal FFC and FFE were not satisfactory. The flow charts describing the accuracy of AS to determine FFE and FC revealed a high level of uncertainty. AS does not reflect in a reliable way FFE in CF patients without or mild steatorrhea. Its applicability in the assessment of FFC in such patients has therefore limited practical value.

Assessment of the disposition of chiral polychlorinated biphenyls in female mdr 1a/b knockout versus wild-type mice using multivariate analyses

Polychlorinated biphenyls (PCBs) are present in the environment as complex mixtures, which make it challenging to identify PCB congeners that may be subject to active transport processes. Here we employ a transgenic mouse model in combination with multivariate analyses to investigate if chiral PCBs 91, 95, 132, 136, 149, 174, 176 and 183 are subject to active (enantioselective) transport by multidrug resistance (MDR) transporters. A synthetic PCB mixture containing these congeners was administered orally to female FVB or mdr1a/1b knockout mice. Due to the short half-life of chiral PCB congeners, mice were euthanized after 24 h and PCB concentrations and enantiomeric fractions were determined in selected tissues and excreta. Principal component analysis did not reveal differences between wild-type and mdr1a/1b knockout mice. However, Hotelling T 2-test revealed significantly lower PCB concentrations and a more pronounced enantiomeric enrichment in the adipose tissue of mdr1a/1b knockout mice. These differences are due to higher body weights and higher fecal fat contents of mdr1a/1b knockout mice. Analysis of the enantiomeric fractions of PCBs 91, 95, 136, 149 and 174 showed a significant enantiomeric enrichment for all five congeners in wild-type and mdr1a/1b knockout mice. Overall, by studying a PCB mixture in a transgenic mouse model in combination with a multivariate data reduction approach, PCBs 91, 95, 136, 149 and 174 could be excluded as substrates of multidrug resistance transporters 1a/b.

Abstract 5537: Inhibition of Pancreatic Lipase and the Renin Angiotensin System Synergistically Decreases Body Fat

We have recently demonstrated that mice lacking renin are lean, and excrete more fat in the feces, which is associated with less than 20 % expression of pancreatic lipase and colipase. Treating wild type (WT) mice with an angiotensin receptor blocker losartan (ARB) or an angiotensin converting enzyme (ACE) inhibitor enalapril does not affect body weight, body fat, fecal fat excretion and pancreatic lipase expression, although their colipase expression in the pancreas is decreased to the low levels of the Ren1c −/− mice. Because colipase is necessary for activation of lipase, we hypothesized that inhibition of both pancreatic lipase and colipase by combination of ARB or ACE inhibitor and lipase inhibitor (orlistat) more effectively decreases body weight and body fat than either of them alone. Treating WT mice with both losartan (0.45g/L in drinking water) and orlistat (200 mg/kg diet) for two weeks reduced the body fat significantly more than mice treated with losartan alone or orlistat alone (control 12.5±1.42 %, losartan 8.7±1.9 %, orlistat 3.8±0.8 %, losartan + orlistat 0.2±2.5 %). The fecal fat content in mice treated with losartan and orlistat is also significantly higher than that of mice treated with losartan alone or orlistat alone (control 46.1±6.2 mg/day, losartan 32.0±4.0 mg/day, orlistat 137.1±9.6 mg/day, losartan + orlistat 186.0±39.6 mg/day). We conclude that inhibiting pancreatic lipase and colipase by using combination of lipase inhibitor and ARB or ACE inhibitor is a promising treatment of the metabolic syndrome. This research has received full or partial funding support from the American Heart Association, Mid-Atlantic Affiliate (Maryland, North Carolina, South Carolina, Virginia &amp; Washington, DC).

Orlistat

Orlistat

Expression of stanniocalcin-1 in gastrointestinal tracts of neonatal and mature rats

Stanniocalcin-1 (STC-1) produced by ovaries endocrinologically targets to mammary glands and is secreted into milk during lactation. The decline of mother’s serum level by STC-1 antiserum administration reduced the milk fat content and the pups’ body fat content. Nevertheless, the pups’ fecal fat content was increased, suggesting that milk-derived STC-1 could influence intestinal fat absorption. We investigated the STC-1 expression in rat gastrointestinal tissues using immunocytochemistry and in situ hybridization. STC-1 was widely expressed in the chief cells of gastric pits and the cells of intestinal glands. Goblet cells in the small intestine contained STC-1 protein in their mucus. The distribution shows that this peptide is secreted exocrinologically into the gastrointestinal lumen. Quantitative RT-PCR analysis revealed that the expression ratio was higher in the periods of heavy nutritional demand, such as growing and lactation. The endogenous STC-1, similar to milk-derived STC-1, may be involved in digestion and/or absorption in gastrointestinal organs.

DIETARY protein and fat content of feces.

Journal Article Dietary Protein and Fat Content of Feces Get access Nutrition Reviews, Volume 12, Issue 5, May 1954, Pages 140–142, https://doi.org/10.1111/j.1753-4887.1954.tb03240.x Published: 01 May 1954

Diet-induced alterations in intestinal and extrahepatic lipid metabolism in liver fatty acid binding protein knockout mice

Liver fatty acid binding protein (L-FABP) is highly expressed in both enterocytes and hepatocytes and binds multiple ligands, including saturated (SFA), unsaturated fatty acids (PUFA), and cholesterol. L-fabp (-/-) mice were protected against obesity and hepatic steatosis on a high saturated fat (SF), high cholesterol "Western" diet and manifested a similar phenotype when fed with a high SF, low cholesterol diet. There were no significant differences in fecal fat content or food consumption between the genotypes, and fatty acid (FA) oxidation was reduced, rather than increased, in SF-fed L-fabp (-/-) mice as evidenced by decreased heat production and serum ketones. In contrast to mice fed with a SF diet, L-fabp (-/-) mice fed with a high PUFA diet were not protected against obesity and hepatic steatosis. These observations together suggest that L-fabp (-/-) mice exhibit a specific defect in the metabolism of SFA, possibly reflecting altered kinetics of FA utilization. In support of this possibility, microarray analysis of muscle from Western diet-fed mice revealed alterations in genes regulating glucose uptake and FA synthesis. In addition, intestinal cholesterol absorption was decreased in L-fabp (-/-) mice. On the other hand, and in striking contrast to other reports, female L-fabp (-/-) mice fed with low fat, high cholesterol diets gained slightly less weight than control mice, with minor reductions in hepatic triglyceride content. Together these data indicate a role for L-FABP in intestinal trafficking of both SFA and cholesterol.

Digestive function of the residual pancreas after partial duodenopancreatectomy for chronic pancreatitis (author's transl)

Forty-eight patients with chronic recurrent pancreatitis treated by resection of the head of the pancreas were restudied more than a year post-operatively. In addition to general features such as symptoms, alcohol consumption and work ability, faecal weight, its fat content, fat and fatty acid balance and faecal chymotrypsin were measured. According to the patients' own estimate, late results were good or very good in 70-90%. Faecal fat content and balance indicated high-grade exocrine pancreatic insufficiency in 80 and 90%, respectively. But it was easily controlled by drugs. In a third of the cases there was the need to supplement the diet with medium-chain triglycerides. Its components are satisfactorily absorbed even when the fat utilisation is severely abnormal.

Intermediate outcomes after serial transverse enteroplasty in children with short bowel syndrome

Background Serial transverse enteroplasty (STEP) is a novel intestinal lengthening procedure introduced in 2003. To date, no human studies exist that report objective assessment of intestinal absorptive capacity. The aim of this study was to report intermediate outcomes in patients who have received the STEP at our institution using clinical and biochemical assessment of intestinal function. Methods All 14 patients who received the STEP since May 2003 were reviewed. Clinical (weight gain, enteral tolerance, stool frequency) and biochemical (citrulline levels, d-xylose absorption, alpha-1 antitrypsin clearance, and fecal fat content) outcomes were performed pre-STEP and post-STEP at 1, 6, and 12 months, respectively. Data are presented as means with standard deviation. Paired t tests were used to compare post-STEP outcomes with pre-STEP values ( P < .05 was significant). Three patients had a STEP as a newborn and are analyzed separately. Main Results There were 14 patients (3 females; mean age, 24.8 months; range, 1 day-14 years). Serial transverse enteroplasty resulted in a mean increase in length of dilated bowel segment of 94% ± 30% and increase in total small bowel length of 49% ± 42% with mean application of 16 ± 9 cartridges and cost of Can$2878.51 ± 1406.22. Patients demonstrated improvement in both clinical parameters, as well as intestinal absorptive function. Complications included 2 patients with staple line leak and 1 patient with gastrointestinal bleeding from staple line ulcers. Three patients died (2 from liver failure and 1 from sepsis and congenital heart disease). Two patients received liver-intestinal transplants at 4 and 5 months post-STEP. Mean follow-up was 23 ± 9 months, with 7 patients followed more than 2 years. Of 8 patients with post-STEP follow-up of more than 1 year, 7 have weaned from parenteral nutrition. Conclusion Clinical and objective biochemical outcomes of intestinal function after the STEP procedure show promise after intermediate follow-up.

Neonatal jaundice and stool production in breast- or formula-fed term infants

It has remained unclear whether the amount of fecal fat excreted in the stool and stool production influences the severity of neonatal jaundice. We determined the relationship between stool production, fecal fat excretion and jaundice in healthy breast-fed (BF) or formula-fed (FF) (near-)term neonates. From postnatal day 1–4, we quantitatively collected stools from 27 FF and 33 BF infants in daily fractions. Stool production and fecal fat contents were related to unconjugated bilirubin (UCB) levels, as determined by transcutaneous bilirubinometry (TcB). Bilirubin concentrations and stool production did not differ between FF and BF neonates during the study period. Neonatal bilirubin levels were not inversely correlated with stool production. FF and BF infants had similar fecal fat excretion rates. The stool production of FF infants was profoundly lower in the present study than in a 1985 study by De Carvalho et al. [J Pediatr (1985) 107:786–790]. We conclude that increased jaundice during the first postnatal days in healthy term neonates can no longer be attributed to breast-feeding and speculate that improved absorbability of formulas since 1985 has contributed to similar fat excretion and stool production in FF and BF neonates in 2007.

Treatment with a Cholesterol Absorption Inhibitor (FM-VP4) Reduces Body Mass and Adipose Accumulation in Developing and Pre-Obese Mice

Objective: Disodium ascorbyl phytostanol phosphate (FM-VP4) is a cholesterol absorption inhibitor, a new class in cholesterol-lowering drug. Previous research on the lipid-lowering and anti-atherosclerotic effects of this drug has reported that administration of FM-VP4 results in a decrease in body mass. This study examined the FM-VP4 dose-dependent mass loss in mice and investigated some potential mechanisms by which decreased mass accumulation may have occurred. The effect of FM-VP4 administration on pre-obese mice was also tested.Research Methods and Procedures: We conducted a dose-dependent study on mouse growth, food and water intake, organ mass, femur length, resting metabolic rate (RMR), maximal oxygen consumption under various conditions (VO2swim and VO2heliox), and fecal fat and plasma assessment for cholesterol and non-esterified fatty acids (NEFA) in mice fed a low fat (LF) or high fat (HF) diet, with or without FM-VP4. The ratio of lean to fat body mass of each animal was also assessed using magnetic resonance spectroscopy. To establish the effect of FM-VP4 on pre-existing obesity, mice were fed a high fat diet for 57 days, followed by administration of a diet containing 2% (w/w) FM-VP4 for 93 days.Results: Animals exhibit a dose-dependent decline in body mass without a concomitant decrease in food intake, water intake, spleen, heart, or kidney mass, femur length or lean body mass. A dose-dependent trend toward a reduction in fat mass was observed in both high fat and low fat diet groups, becoming significant at a 1 and 2% FM-VP4 dosage (w/w). No FM-VP4 induced change in food or water intake, or resting metabolic rate was observed; however, an increase in VO2swim was observed in the 2% FM-VP4 group over HF control. These findings were also observed in the pre-obese group treated with 2% FM-VP4.Discussion: We found a dose dependent reduction in mass accumulation in mice treated with FM-VP4. This loss of mass is not due to an increase in resting metabolic rate or decreased food or water intake. The only tissues exhibiting a decrease in mass with FM-VP4 treatment are liver and body fat. Fecal fat content increased significantly with FM-VP4 treatment in a dose-dependent manner, suggesting that the treatment reduces mass accumulation through decreased absorption or increased excretion of lipids.

Influence of encapsulation of emulsified lipids with chitosan on their in vivo digestibility

The influence of interfacial composition on the in vivo digestibility of emulsified and encapsulated lipids was investigated. An electrostatic layer-by-layer deposition technique was used to prepare soybean oil-in-water emulsions that contained lipid droplets coated by lecithin or by lecithin–chitosan. Thirty six 4-week-old male mice were divided into four groups and fed treatment diets for 4 weeks; atherogenic diets supplemented with (A) non-emulsified fat, without chitosan (control), (B) non-emulsified fat, with chitosan, (C) emulsified fat, without chitosan, or (D) emulsified fat encapsulated by chitosan. There were no differences in body weights, food intake, major organ weights, or fecal fat contents between all treatment groups, where total fat absorption was >90%. The results suggest that encapsulation of lipids by chitosan does not inhibit their in vivo digestibility, even though previous studies indicate that chitosan does inhibit their in vitro digestibility. Consequently, it should be possible to use chitosan to microencapsulate lipids and lipid-soluble components without compromising their bioavailability, although further human studies are needed to confirm this.

Qualidade do leite de cabra in natura e do produto pasteurizado armazenados por diferentes períodos

QUALITY OF IN NATURA GOAT MILK AND PASTEURIZED PRODUCT STORED FOR DIFFERENT PERIODS. Different periods (0, 3 and 6 days) and 2 temperatures (4 °C and 10 °C) of raw goat’s milk storage and its impact on pasteurized product quality and shelf life were evaluated. In the described periods, slow pasteurization (65 °C/30 min) was carried out and the pasteurized product was stored at 10 °C for 6 days. Raw milk samples were characterized after milk handling and after 3 and 6 days of storage. Pasteurized milk was evaluated immediately after heat treatment and after 3 and 6 days of storage at 10 °C. The counting of mesophiles, total, lipolytic and proteolytic psichotrophic bacteria, total and fecal coliforms, acidity, fat and free fatty acid (FFA) contents were determined. The microorganisms’ populations had a higher growth at 10 °C than 4 °C. Acidity remained in acceptable levels during storage at 4 °C for 6 days, but not at 10 °C. There was a significant decrease (p < 0.05) in raw milk fat content during storage in both temperatures and a gradual increase of free fatty acids (FFA). Pasteurization was efficient in the reduction of bacteria populations and the lipolytic and proteolytic psichrotrophic microorganisms were non-detectable after heat treatment. However, alterations during raw milk storage affected physical-chemical characteristics of pasteurized milk. During storage, values of pasteurized milk acidity and fat content remained stable, while the amount of FFA increased significantly. It was concluded that raw goat’s milk can be stored for up to 3 days at 4 °C before heat treatment. This condition promotes 6 days of shelf-life after pasteurization. In addition, 10 °C is not a suitable

Globin Digest: No Evidence for a Weight Loss Mechanism

This study was designed to document the mechanism through which globin digest, a dietary herbal supplement, might cause weight loss by exploring possible fat malabsorption, calorie malabsorption, energy expenditure, and fat oxidation. Six healthy subjects were placed on an outpatient diet for 14 days and given a meal containing 40.9 g of fat on days 5 and 11, and stools were collected for 72 hours after each meal for analysis of fecal fat content. Four grams of globin digest was given with one meal and placebo with the other. In another separate study, six subjects were placed on a 100-g fat, weight-maintaining diet for 14 days. All food was prepared by the Pennington Center (Baton Rouge, LA) metabolic kitchen. Globin digest (2 g) or placebo was given with each of three meals per day, and stool was collected for calorie determinations during the last 72 hours of each week. Subjects received globin digest during one of the 2 weeks and placebo during the other. Resting metabolic rate and respiratory quotient were measured on the last day of each 1-week period. There was no increase in 72-hour fecal fat or fecal calories by bomb calorimetry during either of the studies. There was no difference in the respiratory quotient. Globin digest did result in an increase in resting metabolic rate. However, this increase was not statistically significant. Globin digest, if effective, does not cause weight loss or fat loss through fat malabsorption or a relative increase in fat oxidation. Future studies are needed to document the efficacy of globin digest for weight loss in humans before further mechanistic investigation is attempted.

Does Secretin-stimulated MRCP Predict Exocrine Pancreatic Insufficiency?

Data on magnetic resonance cholangiopancreatography with secretin stimulation (S-MRCP) for the assessment of exocrine pancreatic insufficiency (EPI) are limited. We compared pancreatic function tests with the findings of S-MRCP in patients with chronic pancreatitis (CP) and disease controls. S-MRCP was performed in 23 patients (18 CP, 5 disease controls). MRCP images were analyzed for secretin-induced duodenal liquid filling (0=no filling; 1=duodenal bulb; 2=up to lower flexure; 3=beyond lower flexure). EPI was evaluated by fecal elastase, fecal fat concentration, and a 13C mixed chain triglyceride breath test. Clinically relevant EPI was stated if 2 of 3 tests were pathologic. EPI was diagnosed in 10 of 18 patients with CP. Patients without EPI showed either grade 2 (n=4) or grade 3 (n=9) duodenal filling, whereas only 1/10 patients with EPI showed grade 3 duodenal filling. Sensitivity and specificity of S-MRCP for the diagnosis of EPI were 69% and 90%, respectively. Assessment of duodenal filling should be performed in patients who undergo S-MRCP for the evaluation of pancreatic morphology. However, minor degrees of duodenal filling are equivocal and require further diagnostic evaluation.

Influence of Cholesterol and Fat in Food on Indirect Parameters of Exocrine Pancreatic Function

Fecal elastase 1, chymotrypsin activity, and fat content in stool are clinical parameters of exocrine pancreatic function. The aim of this study was to clarify the possible impact of extreme changes in diet on fecal enzyme concentration/activity, since extreme diets may lead to wrong conclusions in the diagnosis of pancreatic insufficiency. Twelve healthy test persons followed 4 diet phases, each with a duration of 6 days. The 4 diet phases were (1) nearly fat-free with a low-cholesterol content; (2) high in fat and low in cholesterol; (3) high in cholesterol deriving from meat, and (4) high in cholesterol deriving from eggs. At the end of each diet phase, a 72-hour stool collection was carried out to measure fecal elastase 1, chymotrypsin and fecal fat content. The results showed no significant changes after each of the 4 diet phases. The clinical parameters of fecal elastase 1 and chymotrypsin activity in stool do not seem to be significantly influenced by fat and cholesterol deriving from food.

Passive immunization of lactating mice with stanniocalcin-1 antiserum reduces mammary gland development, milk fat content, and postnatal pup growth

During pregnancy and lactation in rodents, stanniocalcin-1 (STC-1) production by the ovaries is upregulated markedly and released into the circulation. The mammary glands are one target of this systemically delivered hormone. The purpose of this study was to lower serum levels of STC-1 in lactating mice through passive immunization so as to monitor the effects on mammary gland function and postnatal pup growth. Passive immunization significantly reduced circulating hormone levels, and pup growth was significantly compromised (30%), even though control and experimental litters had ingested equal amounts of milk. When mammary glands were analyzed, the alveolar area was significantly reduced in antibody-treated mothers. An analysis of milk composition revealed no changes in lactose, protein, or electrolyte levels but an approximately 40% reduction in triglyceride levels. The latter was due to a significant reduction in mammary gland lipoprotein lipase activity and led to a significant buildup of triglycerides in the serum. Body fat content was also significantly reduced in pups from antibody-treated mothers, whereas pup fecal fat content was increased. In mothers, passive immunization also caused significant behavioral effects, in particular, increased locomotor and hindleg rearing activities. Collectively, the results suggest that systemically derived STC-1 has important effects on mammary gland development and the transfer of serum-based triglycerides into milk. Locomotor effects suggest that STC-1 also has a role in maternal behavior.

Fecal energy losses in enterally fed intensive care patients: An explorative study using bomb calorimetry

Early enteral nutrition and tailored supply of nutrients have become standard in most of the intensive care units (ICU). So far little attention has been given to losses of energy in the stools. The purpose of this explorative study was to evaluate the energy losses of patients with loose stools, necessitating the use of a feces-collector device in a tertiary academic ICU. In a group of 13 fully enterally fed and mechanically ventilated patients with loose stools, the daily energy loss in feces was determined, using bomb calorimetry. Malabsorption was defined as an absorption capacity of 85% or less. Energy expenditure was determined with indirect calorimetry. Six out of 13 (46%) patients fulfilled the criterion of malabsorption. The mean total energetic absorption capacity was 84.6+/-13.3%. The mean capacity of absorption of fat was 89.7+/-16.3%. The caloric value of energy loss had a mean of 301+/-259 kcal/day. Fecal fat loss proved not to be a good indicator of total fecal energy loss. A total of 4/13 patients (31%) had a net negative energy balance of over 500 kcal/day. A daily feces production of 250 g or more was a good predictor of malabsorption. Energy loss could accurately be predicted by using a factor 4.87 for the combined energetic value of protein and carbohydrates, if dry weight and fecal fat content are known. In this clinical study on ICU patients with loose stools, malabsorption proved to be a frequently occurring and so far unrecognized problem, contributing strongly to negative energy balances in 1/3 of the patients.

The Farnesoid X Receptor Modulates Adiposity and Peripheral Insulin Sensitivity in Mice

The farnesoid X receptor (FXR) is a bile acid (BA)-activated nuclear receptor that plays a major role in the regulation of BA and lipid metabolism. Recently, several studies have suggested a potential role of FXR in the control of hepatic carbohydrate metabolism, but its contribution to the maintenance of peripheral glucose homeostasis remains to be established. FXR-deficient mice display decreased adipose tissue mass, lower serum leptin concentrations, and elevated plasma free fatty acid levels. Glucose and insulin tolerance tests revealed that FXR deficiency is associated with impaired glucose tolerance and insulin resistance. Moreover, whole-body glucose disposal during a hyperinsulinemic euglycemic clamp is decreased in FXR-deficient mice. In parallel, FXR deficiency alters distal insulin signaling, as reflected by decreased insulin-dependent Akt phosphorylation in both white adipose tissue and skeletal muscle. Whereas FXR is not expressed in skeletal muscle, it was detected at a low level in white adipose tissue in vivo and induced during adipocyte differentiation in vitro. Moreover, mouse embryonic fibroblasts derived from FXR-deficient mice displayed impaired adipocyte differentiation, identifying a direct role for FXR in adipocyte function. Treatment of differentiated 3T3-L1 adipocytes with the FXR-specific synthetic agonist GW4064 enhanced insulin signaling and insulin-stimulated glucose uptake. Finally, treatment with GW4064 improved insulin resistance in genetically obese ob/ob mice in vivo. Although the underlying molecular mechanisms remain to be unraveled, these results clearly identify a novel role of FXR in the regulation of peripheral insulin sensitivity and adipocyte function. This unexpected function of FXR opens new perspectives for the treatment of type 2 diabetes.