Serum metabolic signatures of primary biliary cirrhosis and primary sclerosing cholangitis

BACKGROUND & AIMS: A greater understanding of cholestatic disease is necessary to advance diagnostic tools and therapeutic options for conditions such as primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC). The purpose of this study was to determine and compare the serum metabolomes of patients with PBC (n = 18) or PSC (n = 21) and healthy controls (n = 10) and to identify metabolites that may differentiate these two cholestatic diseases. METHODS AND RESULTS: Using a mass spectrometry-based, non-targeted biochemical profiling approach, we identified 420 serum metabolites, 101 that differed significantly (P ≤ 0.05) between PBC and control groups, 115 that differed significantly between PSC and control groups, and 56 that differed significantly between PSC and PBC groups. Random forest classification analysis was able to distinguish patients with PBC or PSC with 95% accuracy with selected biochemicals reflective of protein and amino acid metabolism identified as the major contributors. Metabolites related to bile acid metabolism, lipid metabolism, inflammation, and oxidative stress/lipid peroxidation were also identified as differing significantly when comparing the disease groups and controls, with some of these pathways differentially affected in the PBC and PSC groups. CONCLUSION: In this study, we identified novel metabolic changes associated with cholestatic disease that were both consistent and different between PBC and PSC. Validation studies in larger patient cohorts are required to determine the utility of these biochemical markers for diagnosis and therapeutic monitoring of patients with PBC and PSC

Post hoc analyses of surrogate markers of non-alcoholic fatty liver disease (NAFLD) and liver fibrosis in patients with type 2 diabetes in a digitally supported continuous care intervention: An open-label, non-randomised controlled study

OBJECTIVE: One year of comprehensive continuous care intervention (CCI) through nutritional ketosis improves glycosylated haemoglobin(HbA1c), body weight and liver enzymes among patients with type 2 diabetes (T2D). Here, we report the effect of the CCI on surrogate scores of non-alcoholic fatty liver disease (NAFLD) and liver fibrosis. METHODS: This was a non-randomised longitudinal study, including adults with T2D who were self-enrolled to the CCI (n=262) or to receive usual care (UC, n=87) during 1 year. An NAFLD liver fat score (N-LFS) >-0.640 defined the presence of fatty liver. An NAFLD fibrosis score (NFS) of >0.675 identified subjects with advanced fibrosis. Changes in N-LFS and NFS at 1 year were the main endpoints. RESULTS: At baseline, NAFLD was present in 95% of patients in the CCI and 90% of patients in the UC. At 1 year, weight loss of ≥5% was achieved in 79% of patients in the CCI versus 19% of patients in UC (p<0.001). N-LFS mean score was reduced in the CCI group (-1.95±0.22, p<0.001), whereas it was not changed in the UC (0.47±0.41, p=0.26) (CCI vs UC, p<0.001). NFS was reduced in the CCI group (-0.65±0.06, p<0.001) compared with UC (0.26±0.11, p=0.02) (p<0.001 between two groups). In the CCI group, the percentage of individuals with a low probability of advanced fibrosis increased from 18% at baseline to 33% at 1 year (p<0.001). CONCLUSIONS: One year of a digitally supported CCI significantly improved surrogates of NAFLD and advanced fibrosis in patients with T2D

Hepatic lipid peroxidation and cytochrome P-450 2E1 in pediatric nonalcoholic fatty liver disease and its subtypes

GOAL: To compare hepatic lipid peroxidation and cytochrome P-450 2E1 (CYP2E1) protein content in liver biopsies from children with nonalcoholic fatty liver disease (NAFLD) and 2 control groups. BACKGROUND: Elevated hepatic lipid peroxidation resulting from increased hepatic CYP2E1 enzyme activity is involved in the pathogenesis of NAFLD and nonalcoholic steatohepatitis (NASH) in adults, but studies in children are lacking. STUDY: Liver biopsies from 59 children with NAFLD (49 with NASH), 10 children with normal liver histology, and 9 children with mild chronic hepatitis C (HCV) infection were examined. Hepatic malondialdehyde (a measure of lipid peroxidation) levels and CYP2E1 protein content were quantitated, as a percentage of the total area, by immunohistochemical staining of liver biopsy material followed by digital image quantitation. RESULTS: Lipid peroxidation was significantly greater in NAFLD liver biopsies (46.7 ± 20.8%) compared with biopsies from children with normal liver histology (7.6 ± 9.4%; P<0.001) or HCV infection (7.7 ± 7.6%; P<0.001). However, hepatic CYP2E1 expression was not different across the NAFLD, normal liver histology, and HCV groups (60.7 ± 8.7%, 53.5 ± 10.7%, and 60.0 ± 11.9%, respectively; P=0.116). Among children with NAFLD, lipid peroxidation and CYP2E1 protein content did not differ between biopsies with and without NASH. Body mass index was independently associated with hepatic lipid peroxidation levels (r=0.549; P<0.001). CONCLUSIONS: Hepatic lipid peroxidation is increased in children with NAFLD but this is not related to hepatic CYP2E1 expression. No difference in lipid peroxidation in pediatric NAFLD versus NASH argues against a role in disease progression

Relationship of Enhanced Liver Fibrosis Score with Pediatric Nonalcoholic Fatty Liver Disease Histology and Response to Vitamin E or Metformin

OBJECTIVES: To study the diagnostic performance of the enhanced liver fibrosis score (ELF) for detecting different stages of fibrosis and its usefulness in detecting histologic response to vitamin E or metformin in children with nonalcoholic fatty liver disease who participated in the Vitamin E or Metformin for the Treatment Of NAFLD In Children (TONIC) trial. STUDY DESIGN: ELF was measured at baseline and weeks 24, 48, and 96 on sera from 166 TONIC participants. Associations between ELF with baseline and end of trial (EOT) fibrosis stages and other histologic features were assessed using χ2 tests and logistic regression models. RESULTS: ELF was significantly associated with severity of fibrosis at baseline and EOT. ELF areas under the curve for discriminating patients with clinically significant and advanced fibrosis were 0.70 (95% CI, 0.60-0.80) and 0.79 (95% CI, 0.69-0.89), respectively. A 1-unit decrease in ELF at EOT was associated with overall histologic improvement (OR, 1.86; 95% CI, 1.11-3.14; P = .02), resolution of steatohepatitis (OR, 1.88; 95% CI, 1.09-3.25; P = .02), improvement in steatosis grade (OR, 1.76; 95% CI, 1.06-2.82; P = .03), and hepatocellular ballooning (OR, 1.79; 95% CI, 1.06-3.00; P = .03), but not with improvement in fibrosis stage (OR, 1.26; 95% CI, 0.78-2.03; P = .34). CONCLUSIONS: ELF was associated with fibrosis stage in children who participated in TONIC. Although not associated with improvement in fibrosis, a decrease in ELF at EOT was associated with Nonalcoholic Steatohepatitis resolution and improvement in nonalcoholic fatty liver disease histology. ELF may be a useful noninvasive test to monitor treatment response in children with nonalcoholic fatty liver disease

Metabolic Syndrome Abolishes Glucagon-Like Peptide 1 Receptor Agonist Stimulation of SERCA in Coronary Smooth Muscle

Metabolic syndrome (MetS) doubles the risk of adverse cardiovascular events. Glucagon-like peptide 1 (GLP-1) receptor agonists induce weight loss, increase insulin secretion, and improve glucose tolerance. Studies in healthy animals suggest cardioprotective properties of GLP-1 receptor agonists, perhaps partially mediated by improved sarco-endoplasmic reticulum Ca(2+) ATPase (SERCA) activity. We examined the acute effect of GLP-1 receptor agonists on coronary smooth muscle cells (CSM) enzymatically isolated from lean, healthy Ossabaw miniature swine. Intracellular Ca(2+) handling was interrogated with fura-2. The GLP-1 receptor agonist exenatide activated SERCA but did not alter other Ca(2+) transporters. Further, we tested the hypothesis that chronic, in vivo treatment with GLP-1 receptor agonist AC3174 would attenuate coronary artery disease (CAD) in swine with MetS. MetS was induced in 20 swine by 6 months' feeding of a hypercaloric, atherogenic diet. Swine were then randomized (n = 10/group) into placebo or AC3174 treatment groups and continued the diet for an additional 6 months. AC3174 treatment attenuated weight gain, increased insulin secretion, and improved glucose tolerance. Intravascular ultrasound and histology showed no effect of AC3174 on CAD. MetS abolished SERCA activation by GLP-1 receptor agonists. We conclude that MetS confers vascular resistance to GLP-1 receptor agonists, partially through impaired cellular signaling steps involving SERCA

Poor competitiveness of Bradyrhizobium in pigeon pea root colonisation in Indian soils

Background Pigeon pea, a legume crop native to India, is the primary source of protein for more than a billion people in developing countries. The plant can form symbioses with N2-fixing bacteria, however reports of poor crop nodulation in agricultural soils abound. We report here study of the microbiota associated with pigeon pea, with a special focus on the symbiont population in different soils and vegetative and non-vegetative plant growth. Results Location with respect to the plant roots was determined to be the main factor controlling the microbiota followed by developmental stage and soil type. Plant genotype plays only a minor role. Pigeon pea roots have a reduced microbial diversity compared to the surrounding soil and select for Proteobacteria and especially for Rhizobium spp. during vegetative growth. While Bradyrhizobium, a native symbiont of pigeon pea, can be found associating with roots, its presence is dependent on plant variety and soil conditions. A combination of metagenomic survey, strain isolation and co-inoculation with nodule forming Bradyrhizobium spp. and non-N2 fixing Rhizobium spp. demonstrated that the latter is a much more successful coloniser of pigeon pea roots. Conclusions Poor nodulation of pigeon pea in Indian soils may be caused by a poor Bradyrhizobium competitiveness against non-nodulating root colonisers such as Rhizobium. Hence, inoculant strain selection of symbionts for pigeon pea should not only be based on their nitrogen fixation potential but more importantly on their competitiveness in agricultural soils

Effect of different obesogenic diets on pancreatic histology in Ossabaw miniature swine

OBJECTIVE: Obesity is a factor in the outcome and severity of pancreatic conditions. We examined the effect of hypercaloric diets on the pancreata of Ossabaw swine, a large animal model of metabolic syndrome and obesity. METHODS: Swine were fed with 1 of 4 diets: high-fructose (n = 9), atherogenic (n = 10), modified atherogenic (n = 6), or eucaloric standard diet (n = 12) for 24 weeks. Serum chemistries were measured, and pancreata were examined for histological abnormalities including steatosis, inflammation or fibrosis, insulin content, and oxidative stress. RESULTS: The fructose, atherogenic, and modified atherogenic diet groups exhibited obesity, metabolic syndrome, islet enlargement, and significantly increased pancreatic steatosis (22.9% ± 7.5%, 19.7% ± 7.7%, and 38.7% ± 15.3% fat in total tissue area, respectively) compared with controls (9.3% ± 1.9%; P < 0.05). The modified atherogenic diet group showed significantly increased oxidative stress levels as evidenced by elevated serum malondialdehyde (3.0 ± 3.3 vs 1.5 ± 0.3 μmol/L in controls; P = 0.006) and pancreatic malondialdehyde (0.1 ± 0.12 vs 0.04 ± 0.01 nmol/mg protein in controls; P = 0.01). None of the swine exhibited pancreatitis or cellular injury. CONCLUSIONS: Ossabaw swine fed with a modified atherogenic diet developed significant pancreatic steatosis and increased oxidative stress, but no other histological abnormalities were observed

Ab initio RNA folding by discrete molecular dynamics: From structure prediction to folding mechanisms

RNA molecules with novel functions have revived interest in the accurate prediction of RNA three-dimensional (3D) structure and folding dynamics. However, existing methods are inefficient in automated 3D structure prediction. Here, we report a robust computational approach for rapid folding of RNA molecules. We develop a simplified RNA model for discrete molecular dynamics (DMD) simulations, incorporating base-pairing and base-stacking interactions. We demonstrate correct folding of 150 structurally diverse RNA sequences. The majority of DMD-predicted 3D structures have <4 Å deviations from experimental structures. The secondary structures corresponding to the predicted 3D structures consist of 94% native base-pair interactions. Folding thermodynamics and kinetics of tRNAPhe, pseudoknots, and mRNA fragments in DMD simulations are in agreement with previous experimental findings. Folding of RNA molecules features transient, non-native conformations, suggesting non-hierarchical RNA folding. Our method allows rapid conformational sampling of RNA folding, with computational time increasing linearly with RNA length. We envision this approach as a promising tool for RNA structural and functional analyses

Relationship between site of oesophageal cancer and areca chewing and smoking in Taiwan

Among 309 male patients, those who had heavily consumed betel and tobacco were more likely than nonchewers (OR = 2. 91; 95% CI = 1.36-6.25) and nonsmokers (OR = 2.49; 95% CI = 1.02-6.08) to develop cancer in the upper and middle third of the oesophagus, respectively; the effects of alcohol did not dominate in any third

A comprehensive assessment of environmental exposures among 1000 North American patients with primary sclerosing cholangitis, with and without inflammatory bowel disease

BACKGROUND: The relationships between primary sclerosing cholangitis (PSC) and the environment are largely unknown. AIM: To validate associations reported in previous studies and to identify novel environmental exposures among PSC patients. METHODS: We performed a multicenter, case-control analysis utilising self-administered questionnaires. Responses between cases (n = 1000) and controls (n = 663) were compared using multivariable logistic regression adjusted for age and gender. The model was further stratified based on inflammatory bowel disease (IBD) status (with IBD n = 741 without IBD n = 259). RESULTS: Smoking was associated with PSC only when IBD was present (OR, 0.5; 95% CI 0.4-0.7) but not among those PSC patients without IBD (OR, 0.9; 95% CI 0.7-1.2). Compared to controls, women with PSC (irrespective of the presence of IBD) were less likely to have received hormone replacement therapy (HRT; OR, 0.5; 95% CI 0.4-0.7) and were more likely to have recurrent urinary tract infections (OR, 1.6; 95% CI 1.2-2.3). PSC patients regardless of gender or IBD status were less likely to eat fish (OR, 0.4; 95% CI 0.3-0.6) and grilled/barbecued meat (OR, 0.8; 95% CI 0.7-0.9). In contrast, PSC patients with and without IBD were more likely to consume steak/burgers that were more well done (OR, 1.3; 95% CI 1.2-1.5). CONCLUSIONS: IBD (rather than PSC) is associated with smoking. Women with PSC are more likely to have recurrent urinary tract infections and less likely to receive HRT. Dietary intake and methods of food preparation differ in PSC patients when compared to controls