Excess hepatic storage of triglycerides is considered a benign condition, but nonalcoholic steatohepatitis (NASH) may progress to fibrosis and promote atherosclerosis. Carriers of the TM6SF2 E167K variant have fatty liver as a result of reduced secretion of very‐low‐density lipoproteins (VLDLs). As a result, they have lower circulating lipids and reduced risk of myocardial infarction. In this study, we aimed to assess whether TM6SF2 E167K affects liver damage and cardiovascular outcomes in subjects at risk of NASH. Liver damage was evaluated in 1,201 patients who underwent liver biopsy for suspected NASH; 427 were evaluated for carotid atherosclerosis. Cardiovascular outcomes were assessed in 1,819 controls from the Swedish Obese Subjects (SOS) cohort. Presence of the inherited TM6SF2 E167K variant was determined by TaqMan assays. In the liver biopsy cohort, 188 subjects (13%) were carriers of the E167K variant. They had lower serum lipid levels than noncarriers (P < 0.05), had more‐severe steatosis, necroinflammation, ballooning, and fibrosis (P < 0.05), and were more likely to have NASH (odds ratio [OR]: 1.84; 95% confidence interval [CI]: 1.23‐2.79) and advanced fibrosis (OR, 2.08; 95% CI: 1.20‐3.55), after adjustment for age, sex, body mass index, fasting hyperglycemia, and the I148M PNPLA3 risk variant. However, E167K carriers had lower risk of developing carotid plaques (OR, 0.49; 95% CI: 0.25‐0.94). In the SOS cohort, E167K carriers had higher alanine aminotransferase ALT and lower lipid levels (P < 0.05), as well as a lower incidence of cardiovascular events (hazard ratio: 0.61; 95% CI: 0.39‐0.95). Conclusions: Carriers of the TM6SF2 E167K variant are more susceptible to progressive NASH, but are protected against cardiovascular disease. Our findings suggest that reduced ability to export VLDLs is deleterious for the liver. (Hepatology 2015;61:506‐514)

Variant in glucokinase regulatory protein (GCKR), associated with lipid and glucose traits, has been suggested to affect fatty liver infiltration. We aimed to assess whether GCKR rs780094 C→T SNP influences the expression of steatosis, lobular inflammation and fibrosis in NAFLD patients, after correction for PNPLA3 genotype. In 366 consecutive NAFLD patients (197 from Sicily, and 169 from center/northern Italy), we assessed anthropometric, biochemical and metabolic features; liver biopsy was scored according to Kleiner. PNPLA3 rs738409 C>G and GCKR rs780094 C>T single nucleotide polymorphisms were also assessed. At multivariate logistic regression analysis in the entire NAFLD cohort, the presence of significant liver fibrosis (>F1) was independently linked to high HOMA (OR 1.12, 95% CI 1.01–1.23, p = 0.02), NAFLD activity score ≥5 (OR 4.09, 95% CI 2.45–6.81, pT SNP (OR 2.06, 95% CI 1.43–2.98, pT SNP was also associated with higher serum triglycerides (ANOVA, p = 0.02) in the entire cohort. In patients with NAFLD, GCKR rs780094 C>T is associated with the severity of liver fibrosis and with higher serum triglyceride levels.

Context: Inflammation may have a pathogenic role in the progression of nonalcoholic fatty liver disease (NAFLD); by contrast, the role of anti-inflammatory molecules has not been addressed. Low circulating levels of the anti-inflammatory molecule IGF-I have been described in subjects with NAFLD. Objective: The aim of the study was to elucidate the clinical significance of IGF-I in NAFLD and its relationship with inflammatory biomarkers and fibrosis. Design and Setting: We conducted a cross-sectional study and in vitro experiments on hepatic HepG2 cells at the Internal Medicine and Gastrointestinal and Liver Units of the Universities of Catanzaro and Palermo. Subjects: A total of 221 individuals with NAFLD diagnosed on ultrasonography (cohort 1) and 50 subjects with biopsy-proven NAFLD (cohort 2) participated in the study. Intervention: Liver ultrasonography was performed on cohort 1, and hepatic biopsies were obtained from cohort 2. Main Outcome Measures: NAFLD fibrosis and Kleiner scores were calculated. IGF-I and inflammatory biomarker plasma concentrations were assessed with specific assays. In the in vitro study, real-time RT-PCR was used to assess the mRNA expression levels of acute-phase reactants. Results: In the first cohort, circulating IGF-I levels showed an inverse correlation with NAFLD fibrosis score and inflammatory biomarkers; similarly in the second cohort, liver IGF-I mRNA levels and the fibrosis score showed a negative relationship. Finally, we showed that IGF-I was able to directly modulate the expression of acute-phase reactants, decreasing C-reactive protein and fibrinogen levels and up-regulating albumin expression in HepG2 cells. Conclusions: The present data suggest that evaluation of circulating IGF-I and proinflammatory markers might be useful to assess comprehensively the severity of the disease in individuals with NAFLD.

To evaluate if the presence of carotid atherosclerosis in patients with NAFLD, could be related to gene variants influencing hepatic fat accumulation and the severity of liver damage. We recorded anthropometric, metabolic and histological data(Kleiner score) of 162 consecutive, biopsy-proven Sicilian NAFLD patients. Intima-media thickness(IMT), IMT thickening(IMT≥1 mm) and carotid plaques(focal thickening of >1.3 mm at the level of common carotid artery) were evaluated using ultrasonography. IL28B rs12979860 C>T, PNPLA3 rs738409 C>G, GCKR rs780094 C>T, LYPLAL1 rs12137855 C>T, and NCAN rs2228603 C>T single nucleotide polymorphisms were also assessed. The results were validated in a cohort of 267 subjects with clinical or histological diagnosis of NAFLD from Northern Italy, 63 of whom had follow-up examinations. Carotid plaques, IMT thickening and mean maximum IMT were similar in the two cohorts, whereas the prevalence of diabetes, obesity, NASH, and PNPLA3 GG polymorphism(21%vs.13%, p = 0.02) were significantly higher in the Sicilian cohort. In this cohort, the prevalence of carotid plaques and IMT thickening was higher in PNPLA3 GG compared to CC/CG genotype(53%vs.32%, p = 0.02; 62%vs.28%, p<0.001, respectively). These associations were confirmed at multivariate analyses (OR2.94;95%C.I. 1.12–7.71, p = 0.02, and OR4.11;95%C.I. 1.69–9.96, p = 0.002, respectively), although have been observed only in patients <50years. Also in the validation cohort, PNPLA3 GG genotype was independently associated with IMT thickening in younger patients only (OR: 6.00,95%C.I. 1.36–29, p = 0.01), and to IMT progression (p = 0.05) in patients with follow-up examinations. PNPLA3 GG genotype is associated with higher severity of carotid atherosclerosis in younger patients with NAFLD. Mechanisms underlying this association, and its clinical relevance need further investigations.