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Bariatric surgery elevates serum bile acids. Conjugated bile acid administration, such as tauroursodeoxycholic acid (TUDCA), improves insulin sensitivity, whereas short-circuiting bile acid circulation through ileal interposition surgery in rats raises TUDCA levels. We hypothesized that bariatric surgery outcomes could be recapitulated by short circuiting the normal enterohepatic bile circulation. We established a model wherein male obese rats underwent either bile diversion (BD) or Sham (SH) surgery. The BD group had a catheter inserted into the common bile duct and its distal end anchored into the middistal jejunum for 4–5 weeks. Glucose tolerance, insulin and glucagon-like peptide-1 (GLP-1) response, hepatic steatosis, and endoplasmic reticulum (ER) stress were measured. Rats post-BD lost significantly more weight than the SH rats. BD rats gained less fat mass after surgery. BD rats had improved glucose tolerance, increased higher postprandial glucagon-like peptide-1 response and serum bile acids but less liver steatosis. Serum bile acid levels including TUDCA concentrations were higher in BD compared to SH pair-fed rats. Fecal bile acid levels were not different. Liver ER stress (C/EBP homologous protein mRNA and pJNK protein) was decreased in BD rats. Bile acid gavage (TUDCA/ursodeoxycholic acid [UDCA]) in diet-induced obese rats, elevated serum TUDCA and concomitantly reduced hepatic steatosis and ER stress (C/EBP homologous protein mRNA). These data demonstrate the ability of alterations in bile acids to recapitulate important metabolic improvements seen after bariatric surgery. Further, our work establishes a model for focused study of bile acids in the context of bariatric surgery that may lead to the identification of therapeutics for metabolic disease.

Background Roux-en-Y gastric bypass (RYGB) is the most effective method for the treatment of obesity, and metabolic disease RYGB may reduce body weight by altering the feeding responses evoked by the short-term satiety peptides. Materials and methods Here, we measured meal size (MS, chow), intermeal interval (IMI) length, and satiety ratio (SR, IMI/MS; food consumed per a unit of time) by the small and the large forms of gastrin-releasing peptide (GRP) in rats, GRP-10 and GRP-29 (0, 0.1, 0.5 nmol/kg) infused in the celiac artery (CA, supplies stomach and upper duodenum) and the cranial mesenteric artery (CMA, supplies small and large intestine) in an RYGB rat model. Results GRP-10 reduced MS, prolonged the IMI, and increased the SR only in the RYGB group, whereas GRP-29 evoked these responses by both routes and in both groups. Conclusions The RYGB procedure augments the feeding responses evoked by exogenous GRP, possibly by decreasing total food intake, increasing latency to the first meal, decreasing number of meals or altering the sites of action regulating MS and IMI length by the two peptides.

Bariatric surgery is the most efficacious procedure for eliciting weight loss in humans, and many patients undergoing the procedure experience significant lessening of their symptoms of type-2 diabetes in addition to losing weight. We have adapted two bariatric surgical procedures commonly employed in humans to a rat model to begin to understand the mechanisms underlying the improvements in energy homeostasis. Young adult male rats received either roux-en-Y gastric bypass (RYGB) or vertical sleeve gastrectomy (VSG) and were assessed for body weight, food intake and parameters of glucose homeostasis over a 28-week period. Control rats received either a sham surgical procedure or else were unoperated. RYGB and VSG had comparable beneficial effects relative to controls. They ate less food and lost more weight, and they both had improved glucose parameters. The most intriguing aspect of the findings is that the two surgical procedures had such similar effects in spite of quite different rearrangements of the gastrointestinal system.

Background & Aims Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG) reduce weight and improve glucose metabolism in obese patients, although it is not clear if metabolic changes are independent of weight loss. We investigated alterations in glucose metabolism in rats following RYGB or VSG. Methods Rats underwent RYGB or VSG and were compared to sham-operated rats fed ad lib or pair-fed to animals that received RYGB. Intraperitoneal glucose tolerance and insulin sensitivity tests were performed to assess glycemic function independent of incretin response. A hyperinsulinemic euglycemic clamp was used to compare tissue-specific changes in insulin sensitivity following each procedure. A mixed-meal tolerance test was used to assess the effect of each surgery on postprandial release of glucagon-like peptide 1 (GLP-1)(7-36) and glucose tolerance, and was also performed in rats given GLP-1 receptor antagonist exendin(9-39). Results Following RYGB or VSG, glucose tolerance and insulin sensitivity improved in proportion to weight loss. Hepatic insulin sensitivity was significantly better in rats that received RYGB or VSG compared with rats fed ad lib or pair-fed, whereas glucose clearance was similar in all groups. During the mixed-meal tolerance test, plasma levels of GLP-1(7-36) and insulin were greatly and comparably increased in rats that received RYGB and VSG compared with those that were pair-fed or fed ad lib. Administration of a GLP-1 receptor antagonist prevented improvements in glucose and insulin responses after a meal among rats that received RYGB or VSG. Conclusions In obese rats, VSG is as effective as RYGB for increasing secretion of GLP-1 and insulin and improving hepatic sensitivity to insulin; these effects are independent of weight loss.

The goal of this study was to examine the effect of a standardized silybin and soy phosphatidylcholine complex (IdB 1016) on serum markers of iron status.Milk thistle and its components are widely used as an alternative therapy for liver disease because of purported antioxidant, anti-inflammatory, and iron chelating properties.Thirty-seven patients with chronic hepatitis C and Batts-Ludwig fibrosis stage II, III, or IV were randomized to 1 of 3 doses of IdB 1016 for 12 weeks. Serum ferritin, serum iron, total iron binding capacity, and transferrin-iron saturation were measured at baseline, during treatment, and 4 weeks thereafter. Wilcoxon signed rank tests were used to compare baseline and posttreatment values.There was a significant decrease in serum ferritin from baseline to end of treatment (mean, 244 vs. 215 mug/L; median, 178 vs. 148 mug/L; P=0.0005); 78% of subjects had a decrease in serum ferritin level. There was no significant change in serum iron or transferrin-iron saturation. Multivariate logistic regression analysis in a model that included dose, age, sex, HFE genotype, history of alcohol use, and elevated baseline ferritin levels demonstrated that stage III or IV fibrosis was independently associated with decreased posttreatment serum ferritin level.Treatment with IdB 1016 is associated with reduced body iron stores, especially among patients with advanced fibrosis stage.

Background: It is unclear whether mild to moderate iron overload in liver diseases other than hereditary haemochromatosis (HH) contributes to hepatocellular carcinoma. This study examined the association between hepatic iron grade and hepatocellular carcinoma in patients with end-stage liver disease of diverse aetiologies. Methods: The prevalence of hepatic iron overload and hepatocellular carcinoma was examined in 5224 patients undergoing liver transplantation. Explant pathology reports were reviewed for the underlying pathological diagnosis, presence of hepatocellular carcinoma and degree of iron staining. The distribution of categorical variables was studied using χ2 tests. Results: Both iron overload and hepatocellular carcinoma were the least common with biliary cirrhosis (1.8 and 2.8% respectively). Hepatocellular carcinoma was the most common in patients with hepatitis B (16.7%), followed by those with hepatitis C (15.1%) and HH (14.9%). In the overall cohort, any iron overload was significantly associated with hepatocellular carcinoma (P=0.001), even after adjustment for the underlying aetiology of liver disease. The association between hepatic iron content and hepatocellular carcinoma was the strongest in patients with biliary cirrhosis (P

Several bariatric operations are currently used to treat obesity and obesity-related comorbidities. These vary in efficacy, but most are more effective than current pharmaceutical treatments. Roux-en-Y gastric bypass (RYGB) produces substantial body weight (BW) loss and enhanced glucose tolerance, and is associated with increased secretion of the gut hormone glucagon-like peptide 1 (GLP-1). Given the success of GLP-1–based agents in lowering blood glucose levels and BW, we hypothesized that an individual sensitivity to GLP-1 receptor agonism could predict metabolic benefits of surgeries associated with increased GLP-1 secretion. One hundred ninety-seven high-fat diet–induced obese male Long-Evans rats were monitored for BW loss during exendin-4 (Ex4) administration. Stable populations of responders and nonresponders were identified based on Ex4-induced BW loss and GLP-1–induced improvements in glucose tolerance. Subpopulations of Ex4 extreme responders and nonresponders underwent RYGB surgery. After RYGB, responders and nonresponders showed similar BW loss compared with sham, but nonresponders retained impaired glucose tolerance. These data indicate that the GLP-1 response tests may predict some but not all of the improvements observed after RYGB. These findings present an opportunity to optimize the use of bariatric surgery based on an improved understanding of GLP-1 biology and suggest an opportunity for a more personalized therapeutic approach to the metabolic syndrome.

Objective Surgical interventions that prevent nutrient exposure to the duodenum are among the most successful treatments for obesity and diabetes. However, these interventions are highly invasive, irreversible and often carry significant risk. The duodenal-endoluminal sleeve (DES) is a flexible tube that acts as a barrier to nutrient-tissue interaction along the duodenum. We implanted this device in Zucker Diabetic Fatty (ZDF) rats to gain greater understanding of duodenal nutrient exclusion on glucose homeostasis. Design ZDF rats were randomised to four groups: Naive, sham ad libitum, sham pair-fed, and DES implanted. Food intake, body weight (BW) and body composition were measured for 28 days postoperatively. Glucose, lipid and bile acid metabolism were evaluated, as well as histological assessment of the upper intestine. Results DES implantation induced a sustained decrease in BW throughout the study that was matched by pair-fed sham animals. Decreased BW resulted from loss of fat, but not lean mass. DES rats were also found to be more glucose tolerant than either ad libitum-fed or pair-fed sham controls, suggesting fat mass independent metabolic benefits. DES also reduced circulating triglyceride and glycerol levels while increasing circulating bile acids. Interestingly, DES stimulated a considerable increase in villus length throughout the upper intestine, which may contribute to metabolic improvements. Conclusions Our preclinical results validate DES as a promising therapeutic approach to diabetes and obesity, which offers reversibility, low risk, low invasiveness and triple benefits including fat mass loss, glucose and lipid metabolism improvement which mechanistically may involve increased villus growth in the upper gut.

Vertical sleeve gastrectomy (VSG) effectively reduces body weight (BW) in obese rats and humans. However, post-surgical weight regain is frequently observed in subjects after VSG, but the underlying reasons remain poorly understood. We therefore investigated if post-surgical consumption of different diets can affect the outcome of VSG. VSG or sham operation was performed in Long–Evans rats with diet-induced obesity (n = 37). After post-surgical recovery, rats were fed ad libitum either with standard chow (CH), high-fat (HF) or low-carbohydrate, high-fat (LCHF) diets. BW and food intake were measured every second day; serum leptin, cholesterol, HDL cholesterol, and triglycerides were analyzed 4 weeks after surgery. Energy expenditure and locomotor activity were determined by a combined indirect calorimetry system, lean and fat mass by nuclear magnetic resonance. After 4 weeks, BW gain, fat mass, and leptin were lower in VSG rats when compared to sham controls (p

It is unclear whether mild to moderate iron overload in liver diseases other than hereditary haemochromatosis (HH) contributes to hepatocellular carcinoma. This study examined the association between hepatic iron grade and hepatocellular carcinoma in patients with end-stage liver disease of diverse aetiologies.The prevalence of hepatic iron overload and hepatocellular carcinoma was examined in 5224 patients undergoing liver transplantation. Explant pathology reports were reviewed for the underlying pathological diagnosis, presence of hepatocellular carcinoma and degree of iron staining. The distribution of categorical variables was studied using chi(2) tests.Both iron overload and hepatocellular carcinoma were the least common with biliary cirrhosis (1.8 and 2.8% respectively). Hepatocellular carcinoma was the most common in patients with hepatitis B (16.7%), followed by those with hepatitis C (15.1%) and HH (14.9%). In the overall cohort, any iron overload was significantly associated with hepatocellular carcinoma (P=0.001), even after adjustment for the underlying aetiology of liver disease. The association between hepatic iron content and hepatocellular carcinoma was the strongest in patients with biliary cirrhosis (P0.001) and hepatitis C (P0.001).Iron overload is associated with hepatocellular carcinoma in patients with end-stage liver disease, suggesting a possible carcinogenic or cocarcinogenic role for iron in chronic liver disease.

To investigate associations between survival and use of psychological and spiritual activities practiced over 1 year in HIV-positive (HIV+) patients.Nine hundred one HIV+ adults living in the United States using at least 1 form of complementary and alternative medicine (CAM) completed a questionnaire 3 times between 1995 and 1998. Information on specific mind-body therapies included psychotherapy (group therapy, support groups, individual therapy) and spiritual therapies (self-defined "spiritual" activities, prayer, meditation, affirmations, psychic healing, visualizations). Subsequent death was ascertained from the National Death Index (NDI). Cox proportional-hazards regression assessed risk of death through 1999.Use of any psychological therapy reported in both the 6-month and 12-month follow-up questionnaires (1 year continuous use) was associated with a reduced risk of death (hazard ratio [HR]: 0.5, 95% CI: 0.3-0.9) adjusted for income, clinical acquired immune deficiency syndrome, CD4 count, smoking, alcohol use, and use of antiretroviral therapy or highly active antiretroviral therapy (HAART). The relationship between spiritual activities and survival was modified by use of HAART, which may reflect severity of illness. Individuals not currently using HAART and who participated in spiritual activities over the previous year were found to be at a reduced risk of death (HR: 0.4, 95% CI: 0.2-0.9) compared to those not practicing spirituality.Participation in spiritual and psychological therapies may be related to beneficial clinical outcomes in HIV+ individuals, including improved survival. Due to the self-selection of therapies in this observational cohort, it is not possible to distinguish use of the therapies from other characteristics or activities of the people participating in them.

Iron accumulates in the Alzheimer's disease (AD) brain and is directly associated with β-amyloid pathology. The proton transverse relaxation rate (R2) has a strong linear relationship with iron concentrations in healthy brain tissue; however, an independent test of this relationship has not been extended to AD brain tissue. In this study in vitro single spin-echo (SE) measurements were made on tissue samples from four human AD brains using a 4.7T MRI research scanner. R2 values were calculated for 14 cortical and subcortical gray matter (GM) and white matter (WM) regions. Atomic absorption spectroscopy was used to measure iron concentrations in the corresponding excised brain regions. Significant positive linear correlations were observed between R2 values and iron concentrations in GM regions assessed across individual tissue samples and data averaged by brain region. With the use of a predictive model for R2, a threshold iron concentration of 55 μg Fe/g wet tissue was determined above which R2 appears to be dominated by the affects of iron in AD brain tissue. High-field MRI may therefore be a useful research tool for assessing brain iron changes associated with AD. Magn Reson Med 57:172–180, 2007. © 2006 Wiley-Liss, Inc.

Background: End-stage cirrhosis in the absence of hereditary hemochromatosis (HHC) can be associated with moderate to marked hepatic iron overload, especially in liver disease as a result of alcohol and/or hepatitis C. However, no published studies have addressed extrahepatic iron deposition in this setting. Method: A retrospective case series from three autopsied patients who died from end-stage cirrhosis associated with significant hepatic iron overload. Histology of vital organs was performed to detect extrahepatic iron deposition. HFE genotyping for the C282Y and H63D mutations was determined from archival tissue. Hepatic iron index and hepatic iron concentration (HIC) were quantified from formalin-fixed, paraffin-embedded tissue. Medical records were reviewed for possible causes of iron overload. Results: Two patients were H63D heterozygous (H63D +/−) and one was wild type (C282Y −/−, H63D −/−). Histology revealed evidence of stainable iron in the heart and pancreas of all three subjects. Additionally, stainable iron was seen in the stomach in one subject and in the thyroid, pituitary, choroid plexus and testes in another subject. HIC ranged from 4354 to 6834 μg/g dry weight and HII from 1.8 to 2.2 (μmol/g/years). Conclusion: Iron overload secondary to end-stage liver disease can be associated with iron deposition in other organs in the absence of HFE-1 HHC.

Silymarin is the main active complex extracted from the milk thistle (Silybum marianum L.), an annual plant that has been used by herbalists since antiquity. Pharmacologic evidence from numerous studies in the last few decades supports potential therapeutic benefits of milk thistle and silymarin in liver necroinflammation and fibrogenesis given its free-radical scavenging, antioxidant, anti-inflammatory, immunomodulatory, iron chelating, and membrane stabilizing properties as well as its purported ability to selectively stimulate hepatocyte proliferation. Current knowledge of the role of oxidative stress in the pathogenesis of alcohol liver disease (ALD), suggests that silymarin’s pharmacological properties may have potential therapeutic value in ALD. Since the 1960s, milk thistle products have been prescribed by physicians in Europe for ALD as well as other liver-related conditions. Several European manufacturers have developed pharmaceutical grade milk thistle products standardized to a higher content of silymarin (70%–80%) than in non-standardized herbal preparations (≈5%), mainly because of silymarin’s poor oral bioavailability. As part of pharmaceutical development, several clinical studies have been conducted in Europe to assess the efficacy of oral milk thistle products in liver diseases of diverse etiology. Recently, a systematic review sponsored by the Agency for Healthcare Research and Quality (AHRQ) selectively analyzed 16 prospective randomized placebo-controlled European trials in terms of the efficacy and safety of milk thistle products in alcohol, viral or toxin-related liver diseases. Six of the selected trials evaluated ALD using various doses of Legalon, a milk thistle product standardized to 80% silymarin manufactured in by Madhaus AG (Cologne, Germany). The reviewers found these trials difficult to interpret due to unclear and variable definitions of disease chronicity and severity. Some of the studies included liver diseases of various etiologies. None of the studies stratified patients by presence or absence of ongoing alcohol consumption or chronic hepatitis C infection as potential confounders. All 6 studies on silymarin and ALD found at least 1 biochemical parameter of liver function or liver histology that improved significantly with silymarin compared with placebo. The parameters that were significant varied from study to study. Importantly, 1 of the 6 studies showed significant improvement in overall survival among cirrhotic patients treated with silymarin, a second study showed a non-statistical trend toward improved survival and yet another study showed no improvement in overall survival in silymarin compared with placebo. No relationship was found between duration of therapy and improvement in liver function, although 3 of the reports did not clearly describe the duration of therapy. The previous data on silymarin in ALD along with current evidence on the potential benefit of antioxidant therapies in ALD, justify a more systematic assessment of silymarin in ALD. Furthermore, an evidence-based approach to the evaluation of the safety and efficacy is crucial because at least 1 multicenter survey has shown that milk thistle is the most frequently used supplement in patients with liver disease. In 2001, milk thistle products ranked 12th in the list of supplements sold in the US surpassing 7 million dollars.

This literature review examines the current state of the scientific evidence published in peer-reviewed journals indexed in MedLine for the 10 most commonly noted alternative activities reported by the first 1,016 eligible participants in the Alternative Medical Care Outcomes in AIDS study. The most frequently used activities are aerobic exercise (64%), prayer (56%), massage (54%), needle acupuncture (48%), meditation (46%), support groups (42%), visualization and imagery (34%), breathing exercises (33%), spiritual activities (33%), and other exercise (33%). Despite frequency of usage, clinical research is not reported on MedLine to support the use of most of these activities for HIV/AIDS. The limitations of using MedLine as the sole source for this review are discussed.

Background & Aims Surgical intervention produces sustainable weight loss and metabolic improvement in obese individuals. Vertical sleeve gastrectomy (VSG) produces dramatic, sustained weight loss; we investigated whether these changes result from improved sensitivity to leptin. Methods VSG was performed in Long–Evans rats with diet-induced obesity. Naive or sham-operated rats, fed either ad libitum or pair-fed with the VSG group, were used as controls. Following surgery, body weights and food intake were monitored. We investigated energy expenditure, meal patterns, leptin sensitivity, and expression of pro-opiomelanocortin/agouti-related peptide/neuropeptide Y in the hypothalamus of the rats. Results We observed sustained losses in weight and body fat in male and female rats after VSG. Weight loss persisted after the disappearance of a transient, postsurgical food intake reduction. Resting energy expenditure was similar between control and VSG rats. VSG rats maintained their reduced body weights. However, they responded to a chronic food restriction challenge by overeating, which resulted in prerestriction, rather than pre-VSG, body weights. Consistent with lower adiposity, VSG decreased plasma leptin levels. Although VSG slightly improved leptin's anorectic action, the response was comparable to that observed in controls matched for adiposity by caloric restriction. Changes in hypothalamic neuropeptide expression were consistent with the lower body weight and lower leptin levels but cannot account for the sustained weight loss. Conclusions VSG causes sustained reduction in body weight, which results from loss of fat mass. The maintenance of weight loss observed did not result from changes in sensitivity to leptin.