The burden of non-alcoholic fatty liver disease (NAFLD) worldwide is a significant clinical and public health issue, affecting approximately one third of the Western population. This review assesses the effect and impact lifestyle interventions have on the treatment of this common condition. We review studies comparing the effect of calorie restriction and exercise programs, as well as comparison of lifestyle intervention with pharmaceutical intervention. Both calorie restriction and exercise programs are shown to be beneficial in improving features of metabolic syndrome and surrogate markers of NAFLD. The paucity of studies using histological improvement hinders the ability to conclude a benefit on improvement of histological NAFLD, although this is shown in a small number of studies. There is a need to extend the intervention period to show a sustained improvement with intervention as most studies have a follow up period of 12 months of less.

This abstract was presented as the Cellular and Molecular Nutrition Theme highlight.Elevated levels of methylglyoxal (MG), a highly reactive glycating agent forming advanced glycation endproducts (AGEs), have been associated with diabetes, obesity and vascular disease (1) . However, its role in the hepatic manifestation of metabolic syndrome, nonalcoholic fatty liver disease (NAFLD), is still a novel inquiry. The objective of these experiments was to assess MG levels in response to lipid loading in the liver.Immortalised human hepatocytes (HepG2 cells) cultured in physiological levels of glucose (5 mM) were treated with either saturated (400 μM palmitic acid, PA) or mono-unsaturated (500 μM oleic acid, OA) fatty acids (n = 3). Fatty acid-induced lipid loading was confirmed by Nile red staining. MG content of cells and in culture medium was measured by stable isotopic dilution liquid chromatography-mass spectrometry (LC-MS/MS) (2) . The MG-derived major AGE, hydroimidazolone MG-H1, was assessed by competitive ELISA in serum samples from a cohort of biopsy-confirmed adult NAFLD patients (n = 62). Sample collection was under full NHS ethical approval and conducted in accordance with the Declaration of Helsinki. One-way ANOVA with Dunnett's test was used to analyse the in vitro data. Pearson or Spearman correlations were used to examine MG-H1 relationship to histological features and clinical biochemistries, followed by multiple linear regression analyses.Fatty acid treatment resulted in a 4-fold increase of intracellular lipid in the OA-treated cells ( Fig. 1; P < 0·01). MG increased by 44 % in OA-treated cells compared to vehicle ( Fig. 2; P < 0·05), while culture medium MG increased by 46 % and 45 % in PA-and OA-treated cells, respectively ( Fig. 3; P < 0·05). Serum MG-H1 (n = 59) was inversely correlated with alanine aminotransferase levels, lobular inflammation and hepatocyte ballooning (P < 0·001). MG-H1 was positively correlated with body mass index (BMI) (P < 0·0001) however, there was no correlation between MG-H1 and steatosis or fibrosis score and, surprisingly, in this cohort BMI was inversely correlated to inflammation and ballooning. The multiple regression analyses resulted in no conclusive relationships between MG-H1 and variables to predict NAFLD activity.Accumulation of MG, as measured by LC-MS/MS, in fatty acid-treated cells and their associated medium suggests lipid accumulation increases MG formation and/or decreases MG metabolism. In contrast, serum MG-H1 from patients with fatty liver measured by ELISA did not correlate with extent of steatosis. If these findings can be corroborated by robust measurement of MG-H1 by LC-MS/MS, increased MG and AGEs formation in hepatic steatosis in vivo may be localised to the liver where proteolysis likely releases increased MG-H1 free adduct into plasma.

London Hospital (RLH), these rates are even higher (12.3% to 13.2% in Reception and 22.9% to 27.3% 1 in Year 6). Our aims were to determine the prevalence of NAFLD in our specialist clinics in our unit and to identify key characteristics of children with NAFLD. Methods Clinical records of patients who attended specialist paediatric Hepatology and Metabolic clinics at RLH in 2012 were reviewed. We recorded demographic information, serum biochemistry (abnormal ALT-females >35 U/L, males >40 U/L), liver screening tests, hepatic ultrasound results and insulin resistance (HOMA-IR) were calculated. Results Twelve of 155 patients (8%) (7/62 Hepatology (11%), 5/ 93 Metabolic (5%) clinics) had evidence of hepatic steatosis on ultrasound. The mean BMI percentile in the Hepatology clinic for NAFLD patients was the 93 rd (vs 63 rd in non-NAFLD patients, P = 0.005), whereas all patients in the metabolic clinic (irrespective of NAFLD) had BMI above 3.5 standard deviations for age. The mean age of patients with NAFLD was similar to that of patients without NAFLD (12.5 vs. 12.1 years), and there was no significant difference in the proportion of males with NAFLD compared to children without.All NAFLD patients had elevated ALT (mean 93, range 38-168). Nine patients with normal ALT (mean 16, range 12-23) had undergone abdominal ultrasound and none of these had signs of steatosis. The mean HOMA-IR in those with radiological evidence of steatosis was significantly greater than those with normal ultrasound (7.64 vs. 3.37, p = 0.005). Only two patients had a liver biopsy, both of which showed advanced fibrosis. Nine patients in the metabolic clinic (10%) with elevated ALT (mean 59, range 36-115) had not had a liver screen or ultrasound. Conclusion Paediatric NAFLD is common in this setting and is associated with raised BMI and elevated insulin resistance. All patients with raised ALT, and none with normal ALT, had steatosis on ultrasound in our cohort. This highlights the importance of screening for liver disease including the use of ultrasonography in at-risk patients with abnormal liver chemistry. There is a need for an evidence-based algorithm to guide liver investigation and referral in children with deranged LFTs.

IntroductionNon-alcoholic fatty liver disease is a common condition affecting up to one third of the US population. The current gold standard diagnostic tool is liver biopsy, which has associated morbidity and mortality concerns, as well as sampling error and inter-observer variability problems. There is an urgent need for the discovery and validation of non-invasive markers of this disease. Many studies have taken a targeted approach, examining the utility of various biochemical and clinical markers thought to be important in the pathogenesis of this condition. Shotgun proteomics offers an untargeted tool for the discovery of protein markers in complex clinical samples.MethodsMaterials: 30 patients with biopsy proven NAFLD were recruited. Patients had negative viral hepatitis screens, negative autoimmune screens, normal iron stores, and were taking no hepatotoxic medications. Biochemical and anthropological measurements were also recorded.MethodSerum samples were pooled into three groups (SS/NASH/NASH fibrosis, F1,2, with n=7 per group). The pooled samples were immunodepleted of the top 91 most abundant proteins. Buffer exchange and lyophilisation was performed before samples were reduced alkylated then digested with trypsin. The resultant peptide mixtures were labelled with iTRAQ tags as per the manufacturers' protocol (Applied Biosystems), and then pooled together. Sample fraction was performed using a reverse phase C18 column at high pH. A total of 88 fractions were collected and combined to 47 fractions based on the appearance of the chromatogram. The 47 fractions were analysed by LC-MS/MS (QTOF, Agilent), using an optimised LC and MS methodology. The resultant MS data were processed using MASCOT Distiller software and the IPI_human database searched for matches. Only proteins with 2 peptide identification and a MASCOT score indicative of identity were included for analysis.ResultsA total of 557 proteins were identified and included for analysis. Previous iTRAQ technical replicate data indicated an error range of 1.13 (±0.10)–1.37 (±0.12). Proteins with fold changes out with this range were considered significantly differentially expressed. At least 10 proteins had a fold change >5 in the NASH early fibrosis group. Interestingly, several protein markers of NAFLD fibrosis previously reported in the literature were also found to be appropriately unregulated in this experiment, including α-2-macroglobulin.ConclusionDiscussion iTRAQ technology is a powerful tool, allowing analysis of up to 8 different samples simultaneously. We have improved our method of sample preparation and processing to increase the number of protein identifications. The findings from this study require further validation.