Synergistic interaction of fatty acids and oxysterols impairs mitochondrial function and limits liver adaptation during nafld progression

The complete mechanism accounting for the progression from simple steatosis to steatohepatitis in nonalcoholic fatty liver disease (NAFLD) has not been elucidated. Lipotoxicity refers to cellular injury caused by hepatic free fatty acids (FFAs) and cholesterol accumulation. Excess cholesterol autoxidizes to oxysterols during oxidative stress conditions. We hypothesize that interaction of FAs and cholesterol derivatives may primarily impair mitochondrial function and affect biogenesis adaptation during NAFLD progression. We demonstrated that the accumulation of specific non-enzymatic oxysterols in the liver of animals fed high-fat+high-cholesterol diet induces mitochondrial damage and depletion of proteins of the respiratory chain complexes. When tested in vitro, 5α-cholestane-3β,5,6β-triol (triol) combined to FFAs was able to reduce respiration in isolated liver mitochondria, induced apoptosis in primary hepatocytes, and down-regulated transcription factors involved in mitochondrial biogenesis. Finally, a lower protein content in the mitochondrial respiratory chain complexes was observed in human non-alcoholic steatohepatitis. In conclusion, hepatic accumulation of FFAs and non-enzymatic oxysterols synergistically facilitates development and progression of NAFLD by impairing mitochondrial function, energy balance and biogenesis adaptation to chronic injury

Alterations of clock gene RNA expression in brain Regions of a triple transgenic model of Alzheimer's Disease

A disruption to circadian rhythmicity and the sleep/wake cycle constitutes a major feature of Alzheimer's disease (AD). The maintenance of circadian rhythmicity is regulated by endogenous clock genes and a number of external Zeitgebers, including light. This study investigated the light induced changes in the expression of clock genes in a triple transgenic model of AD (3×Tg-AD) and their wild type littermates (Non-Tg). Changes in gene expression were evaluated in four brain areas¾suprachiasmatic nucleus (SCN), hippocampus, frontal cortex and brainstem¾of 6- and 18-month-old Non-Tg and 3×Tg-AD mice after 12 h exposure to light or darkness. Light exposure exerted significant effects on clock gene expression in the SCN, the site of the major circadian pacemaker. These patterns of expression were disrupted in 3×Tg-AD and in 18-month-old compared with 6-month-old Non-Tg mice. In other brain areas, age rather than genotype affected gene expression; the effect of genotype was observed on hippocampal Sirt1 expression, while it modified the expression of genes regulating the negative feedback loop as well as Rorα, Csnk1ɛ and Sirt1 in the brainstem. In conclusion, during the early development of AD, there is a disruption to the normal expression of genes regulating circadian function after exposure to light, particularly in the SCN but also in extra-hypothalamic brain areas supporting circadian regulation, suggesting a severe impairment of functioning of the clock gene pathway. Even though this study did not demonstrate a direct association between these alterations in clock gene expression among brain areas with the cognitive impairments and chrono-disruption that characterize the early onset of AD, our novel results encourage further investigation aimed at testing this hypothesis

Analogs in the treatment of chronic hepatitis B: real life experience with tenofovir and entecavir

INTRODUCTION: Tenofovir and entecavir are potent antiviral agents. By suppressing viral replication, they induce histological improvement and finally delay the progression of chronic hepatitis B and the development of complications. They are rarely associated with serious side effects. Our data from a real life experience support data from the literature and suggest some minimal difference that may be useful in tailoring therapy.PATIENTS AND METHODS: We retrospectively analyzed 54 patients affected by chronic hepatitis B (31 and 23 treated by entecavir and tenofovir, respectively). Eight patients were cirrhotic. At baseline and 4-12 and 24 weeks after starting therapy, biochemical and virological analysis were performed in all patients. Renal function tests (serum creatinine, creatinine clearance and blood urea), serum (calcium and phosphate blood level) and urine electrolyte were also studied.RESULTS: All the patients reached virological control within 24 weeks. Only in the group treated by tenofovir we observed a complete viral suppression within 12 weeks. Some patients treated with tenofovir showed increased creatinine clearance without serum creatinine alteration. No significant side effects were reported with the exception of one case of persistent headache in the entecavir group for which the drug was suspended.CONCLUSIONS: Entecavir and tenofovir are effective in suppressing viral replication in patients with chronic hepatitis B. Tenofovir is more potent than entecavir and viral replication is blocked within 12 weeks of therapy. Tenofovir administration is associated with slight increase of creatinine clearance without alteration of serum creatinine levels. The choice of one or the other should be made according to target and specific patients characteristics. In patients with high serum viral load where the complete and quick control of viral replication is the main target, tenofovir may represent the best choice

Two-Dimensional Shear Wave Elastography Versus Transient Elastography: A Non-Invasive Comparison for the Assessment of Liver Fibrosis in Patients With Chronic Hepatitis C

In recent years, several non-invasive methods have been developed for staging liver fibrosis in patients with chronic hepatitis C. A 2D-Shear wave elastography (SWE) technique has been recently introduced on the EPIQ 7 US system (ElastQ), but its accuracy has not been validated in patients with chronic hepatitis C virus (HCV) infection. We enrolled 178 HCV patients to assess their liver fibrosis stage with ElastQ software using transient elastography as a reference standard. The best cut-off values to diagnose ≥ F2, ≥ F3, and F4 were 8.15, 10.31, and 12.65 KPa, respectively. Liver stiffness values had a positive correlation with transient elastography (r = 0.57; p < 0.001). The area under the receiver operating characteristics (AUROC) was 0.899 for ≥ F2 (moderate fibrosis), 0.900 for ≥ F3 (severe fibrosis), and 0.899 for cirrhosis. 2D-SWE has excellent accuracy in assessing liver fibrosis in patients with chronic hepatitis C and an excellent correlation with transient elastograph

Direct‐acting antivirals for HCV treatment in older patients: A systematic review and meta‐analysis

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Direct-acting antivirals for HCV treatment in older patients: A systematic review and meta-analysis

The advent of highly effective and well-tolerated direct antiviral antivirals (DAAs) has dramatically changed the landscape of chronic hepatitis C. The effect of DAAs in older adults is difficult to determine since patients aged >= 65 years were too few in most clinical trials and data mainly come from observational studies. We performed a systematic review and meta-analysis to evaluate the efficacy and safety of DAAs in patients aged 65 and older. PubMed, Scopus, Web of Science, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, HCV-Trials.com databases were searched for literature published until 1 December 2017. English language articles reporting results of phase 2 or 3 randomized controlled trials (RCTs), single-arm clinical trials (SATs) and observational studies were included in the final analysis. All studies included subgroups of older patients and compared their outcomes with younger individuals. By using a random-effects or fixed-effects model, odds ratio (OR) was calculated for the efficacy and safety. Heterogeneity was tested using I-2 statistics. Thirty-seven studies reported data on the DAA efficacy. The OR was 1.66 (95%CI: 1.00-2.75; P = 0.06) in meta-analysis of RCTs, and similar results were found in SATs and observational studies. HCV genotype, stage of fibrosis or HIV co-infection did not affect the rate of SVR in older persons. Prevalence of anaemia (OR 0.26 95%CI: 0.09-0.69; P = 0.007) (OR 0.25 95%CI: 0.09-0.69; P = 0.007) and skin complaints (OR 0.61 95%CI: 0.45-0.83; P = 0.001) was higher in older adults. Finally, geriatric patients affected by chronic HCV infection can be safely treated with DAAs with the same efficacy reported in younger adults

Risk of Statin-Induced Hypertransaminasemia: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Objective: To assess the effect of statins compared with placebo on the risk of developing hypertransaminasemia. Patients and methods: We performed a systematic review of electronic databases and included articles published between January 1, 1965, and April 10, 2017. Randomized clinical trials (RCTs) comparing statins vs placebo were included. Odds ratios (ORs) were pooled in random-effect meta-analyses according to established methods recommended by the Cochrane Collaboration. Results: Seventy-three eligible RCTs, comprising 123,051 patients, were identified. Statins associated with a significantly risk of hypertransaminasemia (OR 1.45; 95% confidence interval [CI], 1.24-1.69; P<.001). Atorvastatin showed the highest odds (OR 2.66; 95% CI, 1.74-4.06; P<.001) followed by rosuvastatin (OR 1.35; 95% CI, 1.06-1.70; P=.01) and lovastatin (OR 1.53; 95% CI, 1.03-2.28; P=.04). Pravastatin, fluvastatin, and simvastatin yielded no statistically different odds compared with placebo. Conclusions: A dose-dependent risk of developing hypertransaminasemia occurs in patients taking atorvastatin, rosuvastatin, and lovastatin

Id2 leaves the chromatin of the E2F4-p130-controlled c-myc promoter during hepatocyte priming for liver regeneration

The Id (inhibitor of DNA binding or inhibitor of differentiation) helix-loop-helix proteins are involved in the regulation of cell growth, differentiation and cancer. The fact that the molecular mechanisms of liver regeneration are not completely understood prompted us to study the fate of Id2 in proliferating liver. Id2 increases in liver regeneration after partial hepatectomy, following the early induction of its gene. Co-immunoprecipitation shows that Id2 forms a complex with E2F4, p130 and mSin3A in quiescent liver and all these components are present at the c-myc promoter as shown using ChIP (chromatin immunoprecipitation). Activation of c-myc during hepatocyte priming (G0-G1 transition) correlates with the dissociation of Id2 and HDAC (histone deacetylase), albeit p130 remains bound at least until 6 h. Moreover, as the G0-G1 transition progresses, Id2 and HDAC again bind the c-myc promoter concomitantly with the repression of this gene. The time course of c-myc binding to the Id2 promoter, as determined by ChIP assays is compatible with a role of the oncoprotein as a transcriptional inducer of Id2 in liver regeneration. Immunohistochemical analysis shows that Id2 also increases in proliferating hepatocytes after bile duct ligation. In this case, the pattern of Id2 presence in the c-myc promoter parallels that found in regenerating liver. Our results may suggest a control role for Id2 in hepatocyte priming, through a p130 dissociation-independent regulation of c-my