Poor Adherence to Mediterranean Diet and Serum Lipopolysaccharide are Associated with Oxidative Stress in Patients with Non-Alcoholic Fatty Liver Disease

Oxidative stress plays a pivotal role in non-alcoholic fatty liver disease (NAFLD). Factors inducing oxidative stress in NAFLD may be several; however, a relationship with the adherence to Mediterranean Diet (Med-diet) and with serum lipopolysaccharide (LPS) has been poorly investigated in this setting. The aim was to investigate factors associated with impaired oxidative stress in NAFLD, focusing on the potential role of LPS and Med-diet. We enrolled 238 consecutive outpatients from the PLINIO study, in whom we measured the soluble Nox2-derived peptide (sNox2-dp), a marker of systemic oxidative stress, and serum LPS. Adherence to Med-diet was investigated by a nine-item validated dietary questionnaire. Serum sNox2-dp and LPS were higher in patients with NAFLD compared to those without (25.0 vs. 9.0 pg/mL, p < 0.001 and 62.0 vs. 44.9 pg/mL, p < 0.001, respectively). In patients with NAFLD, the highest sNox2-dp tertile was associated with the top serum LPS tertile (Odds Ratio (OR): 4.71; p < 0.001), APRI > 0.7 (OR: 6.96; p = 0.005) and Med-diet-score > 6 (OR: 0.14; p = 0.026). Analyzing individual foods, the daily consumption of wine (OR: 0.29, p = 0.046) and the adequate weekly consumption of fish (OR: 0.32, p = 0.030) inversely correlated with the top sNox2-dp tertile. In conclusion, patients with NAFLD showed impaired oxidative stress. Levels of sNox2 correlated with serum LPS and with low adherence to Med-Diet.

Association between non-alcoholic fatty liver disease and obstructive sleep apnea

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is an emerging liver disease and currently the most common cause of incidental abnormal liver tests. The pathogenesis of NAFLD is multifactorial and many mechanisms that cause fatty liver infiltration, inflammation, oxidative stress and progressive fibrosis have been proposed. Obstructive sleep apnea (OSA) may be linked with the pathogenesis and the severity of NAFLD.

AIM

To study the association between NAFLD and OSA considering also the efficacy of continuous positive airway pressure (CPAP) treatment.

METHODS

A PubMed search was conducted using the terms “non-alcoholic fatty liver disease AND (obstructive sleep apnea OR obstructive sleep disorders OR sleep apnea)”. Research was limited to title/abstract of articles published in English in the last 5 years; animal and child studies, case reports, commentaries, letters, editorials and meeting abstracts were not considered. Data were extracted on a standardized data collection table which included: First author, publication year, country, study design, number of patients involved, diagnosis and severity of OSA, diagnosis of NAFLD, patient characteristics, results of the study.

RESULTS

In total, 132 articles were initially retrieved on PubMed search and 77 in the last five years. After removal of irrelevant studies, 13 articles were included in the qualitative analysis. There was a total of 2753 participants across all the studies with a mean age between 42 and 58 years. The proportion of males ranged from 21% to 87.9% and the mean body mass index ranged from 24.0 to 49.9 kg/m². The results of this review showed an increased prevalence of NAFLD in patients with diagnosis of OSA, even in the absence of coexisting comorbidities such as obesity or metabolic syndrome. Furthermore, the severity of NAFLD is associated with the increase in OSA severity. Effective CPAP treatment, although not always decisive, may stabilize or slow NAFLD progression with benefits on metabolic and cardiovascular functions.

CONCLUSION

In NAFLD patients, although asymptomatic, it is recommended to systematically perform polysomnography in order to early and better treat them before the development of potentially life threatening systemic dysfunctions.

AISF update on the diagnosis and management of adult-onset lysosomal storage diseases with hepatic involvement

Lysosomal storage diseases (LSDs) are a heterogeneous group of inherited disorders caused by loss-of-function mutations in genes encoding for lysosomal enzymes/proteins. The consequence is a progressive accumulation of substrates in these intracellular organelles, resulting in cellular and tissue damage. The overall incidence is about 1/8000 live births, but is likely underestimated. LSDs are chronic progressive multi-systemic disorders, generally presenting with visceromegaly, and involvement of the central nervous system, eyes, the skeleton, and the respiratory and cardiovascular systems. The age at onset and phenotypic expression are highly variable, according to the specific enzymatic defect and tissues involved, the residual activity, and the disease-causing genotype. Enzyme-replacement therapies and substrate-reduction therapies have recently become available, leading to the improvement in symptoms, disease progression and quality of life of affected individuals. Liver involvement and hepatosplenomegaly are frequent features of LSDs and a hallmark of adult-onset forms, frequently leading to medical attention. LSDs should therefore be considered in the differential diagnosis of liver disease with organomegaly. The present document will provide a short overview of adult-onset LSDs with hepatic involvement, highlighting the specificities and systemic manifestations of the ones most frequently encountered in clinical practice, which may hint at the correct diagnosis and the appropriate treatment.

Prevalence and Impact of Nonalcoholic Fatty Liver Disease in Atrial Fibrillation

OBJECTIVE

To estimate the prevalence of nonalcoholic fatty liver disease (NAFLD) and its impact on bleeding and thrombotic events in patients with atrial fibrillation (AF).

PATIENTS AND METHODS

Prospective multicenter cohort study including patients with nonvalvular AF receiving vitamin K antagonists (VKAs) or non-VKA oral anticoagulants (NOACs) from February 2008 for patients on VKA and from September 2013 for patients on NOACs. NAFLD was diagnosed using the validated fatty liver index, with a cutoff score of 60 or higher. Primary end points were the occurrence of major bleedings and cardiovascular events (CVEs).

RESULTS

NAFLD was diagnosed in 732 of 1735 (42.2%) patients. Patients with NAFLD were younger, less frequently women, and more likely to be treated with NOACs and to have obesity, dyslipidemia, and persistent/permanent AF. During a median follow-up of 18.7 months (3155 patient-years), we recorded 78 major bleedings (incidence rate, 2.5% per year): 29 (2.1% per year) in patients with and 49 (2.7% per year) in patients without NAFLD (log-rank test P=.23). Univariate Cox proportional regression analysis showed no association of NAFLD with major bleedings (hazard ratio, 0.75; 95% CI, 0.47-1.20; P=.23). One hundred fifty-five CVEs occurred (incidence rate, 3.1% per year). No significant association was found between NAFLD and CVEs (log-rank test P=.12). In the entire population, NOAC use was associated with lower CVEs compared with VKAs (hazard ratio, 0.61; 95% CI, 0.42-0.89; P=.01).

CONCLUSION

NAFLD is highly prevalent in AF but is not associated with higher bleeding or thrombotic risk.

Lysosomal acid lipase activity and liver fibrosis in the clinical continuum of non-alcoholic fatty liver disease

BACKGROUND AND AIMS

Recent evidence showed a reduced activity of the lysosomal acid lipase (LAL) in patients with non-alcoholic fatty liver disease (NAFLD) and cryptogenic cirrhosis (CC). However, the relationship between LAL activity and liver fibrosis has never been investigated.

METHODS

Cross-sectional study including 575 outpatients referred for the management of cardio-metabolic and liver disease. The absence of liver fibrosis was defined by a FIB-4 < 1.30 and NAFLD fibrosis score (NFS) <-1.455. LAL activity was measured with dried blood spot technique.

RESULTS

Overall, 515 patients had a diagnosis of NAFLD (454 NAFL and 61 biopsy-proven NASH) and 60 of CC. The value of LAL activity progressively decreased from healthy subjects to NAFL/NASH patients to CC (P < .001). LAL activity was reduced by 10% in patients with NAFL, by 20% in NASH and by 50% in CC. The prevalence of CC decreased across the tertiles of LAL activity: 22.2% in the lowest, 4.6% in the intermediate and 0.5% in the highest tertile. In NAFLD patients, 69.9% had a FIB4 < 1.30, and 43.1% a NFS <-1.455. Multivariate logistic regression analysis showed that Log (LAL activity) was associated with FIB-4 < 1.30 (Odds ratio [OR] 2.19 95% confidence interval [CI] 1.33-3.62, P = .002) and NFS < -1.455 (OR 2.43, 95% CI 1.51-3.91, P < .001) after adjustment for confounding factors.

CONCLUSIONS

We found a progressive reduction of LAL activity according to liver disease severity. LAL activity was inversely associated with markers of liver fibrosis in patients with NAFLD.

Greater circulating DPP4 activity is associated with impaired flow-mediated dilatation in adults with type 2 diabetes mellitus

BACKGROUND AND AIM

Dipeptidyl peptidase 4 (DPP4) is a key enzyme involved in the regulation of the incretin system exerted by cleaving the glucagon-like peptide 1 (GLP-1); the blockage of DPP4, exerted by the antidiabetic agents DPP4-inhibitors (DPP4-I), results in greater GLP-1 concentration and improved glycaemic control. DPP4 acts also as a pro-inflammatory molecule and mediates vascular damage in experimental models. The relationship between DPP4 activity and endothelial function in diabetes has not been explored yet. Aim of this study was to investigate systemic plasma DPP4 activity in relation to endothelial function in patients with type 2 diabetes mellitus (T2DM).

METHODS AND RESULTS

Sixty-two T2DM individuals were recruited in our Diabetes outpatient clinics, Sapienza University, Rome, Italy. All participants underwent complete clinical work-up; endothelial function was evaluated by flow-mediated dilatation (FMD) test; plasma DPP4 activity was assessed by measuring the 7-amino-4-methylcoumarin (AMC) cleavage rate from the synthetic substrate H-glycyl-prolyl-AMC and compared with DPP4 activity measured in sixty-two age-, sex-, BMI-matched non-diabetic subjects. Patients with T2DM had significantly higher DPP4 activity than non-diabetic individuals (211,466 ± 87657 vs 158,087 ± 60267 nmol/min/ml, p < 0.001); in T2DM patients, greater DPP4 activity significantly correlated with lower FMD whereas was not associated with BMI and metabolic control. Greater systemic DPP4 activity was an independent predictor of reduced FMD after adjusting for age, gender and other confounders.

CONCLUSIONS

Circulating DPP4 activity is increased in individuals with T2DM and associated with signs of endothelial dysfunction such as impaired FMD. DPP4 may negatively affect endothelial function through mechanisms beyond glucose homeostasis and metabolic control.

Reduced lysosomal acid lipase activity: A new marker of liver disease severity across the clinical continuum of non-alcoholic fatty liver disease?

Lysosomal acid lipase (LAL) plays a key role in intracellular lipid metabolism. Reduced LAL activity promotes increased multi-organ lysosomal cholesterol ester storage, as observed in two recessive autosomal genetic diseases, Wolman disease and Cholesterol ester storage disease. Severe liver steatosis and accelerated liver fibrosis are common features in patients with genetic LAL deficiency. By contrast, few reliable data are available on the modulation of LAL activity in vivo and on the epigenetic and metabolic factors capable of regulating its activity in subjects without homozygous mutations of the Lipase A gene. In the last few years, a less severe and non-genetic reduction of LAL activity was reported in children and adults with non-alcoholic fatty liver disease (NAFLD), suggesting a possible role of LAL reduction in the pathogenesis and progression of the disease. Patients with NAFLD show a significant, progressive reduction of LAL activity from simple steatosis to non-alcoholic steatohepatitis and cryptogenic cirrhosis. Among cirrhosis of different etiologies, those with cryptogenic cirrhosis show the most significant reductions of LAL activity. These findings suggest that the modulation of LAL activity may become a possible new therapeutic target for patients with more advanced forms of NAFLD. Moreover, the measurement of LAL activity may represent a possible new marker of disease severity in this clinical setting.

Does Nox2 Overactivate in Children with Nonalcoholic Fatty Liver Disease?

It is unknown whether nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (Nox2) activation is early associated with endotoxemia and liver damage in nonalcoholic fatty liver disease (NAFLD). To address this issue, we evaluated Nox2 activation, oxidative stress, gut permeability, and lipopolysaccharide (LPS) serum levels in 67 children with biopsy-proven NAFLD and 73 controls. Compared with controls, NAFLD patients had higher Nox2 activity, isoprostane, zonulin, and LPS levels. Multivariate linear regression analysis showed that triglycerides, high-density lipoprotein (HDL), homeostatic model assessment-estimated insulin resistance (HOMA-IR), LPS, and isoprostanes were independently associated with Nox2-derivative peptide (sNox2-dp) levels. Within the NAFLD group, patients with nonalcoholic steatohepatitis (NASH) had significant higher levels of sNox2-dp, isoprostanes, LPS, triglycerides, HOMA-IR, fasting glucose and insulin, and lower HDL than those without NASH. Furthermore, sNox2-dp levels were linearly associated with the histological grading of steatosis, inflammation, ballooning, fibrosis, and NAFLD activity score. This study provides evidence that children with NAFLD have Nox2 overactivation compared with controls and significant association with the degree of liver damage. The close relationship between Nox2 and LPS serum levels leads to hypothesize a potential role for gut-derived LPS in eliciting systemic Nox2 activation.

Passive Smoking Exacerbates Nicotinamide-Adenine Dinucleotide Phosphate Oxidase Isoform 2-Induced Oxidative Stress and Arterial Dysfunction in Children with Persistent Allergic Rhinitis

OBJECTIVE

To characterize nicotinamide-adenine dinucleotide phosphate oxidase isoform 2 (NOX2), oxidative stress, and endothelial function in children with and without allergic rhinitis and to ascertain the effect of passive smoke exposure on these factors, because there is an established association between allergic rhinitis and increased cardiovascular risk in adults.

METHODS

We recruited 130 children-65 with persistent allergic rhinitis and 65 healthy controls. A cross-sectional study was performed to compare endothelial function by flow-mediated dilation, blood levels of isoprostanes, serum activity of soluble NOX2-dp (sNOX2-dp), and nitric oxide bioavailability, in these 2 groups of children. Serum cotinine levels were assessed to measure exposure to passive smoking.

RESULTS

Compared with healthy controls, children with persistent allergic rhinitis had significantly higher sNOX2-dp and isoprostanes levels, lower flow-mediated dilation, and reduced nitric oxide bioavailability. Multivariable linear regression analysis showed that flow-mediated dilation, isoprostanes, and cotinine were independently associated with sNOX2-dp levels. Of note, sNOX2-dp serum levels were significantly higher in children with allergic rhinitis exposed to smoke, as compared with unexposed children with allergic rhinitis.

CONCLUSION

NOX2 is activated in children with persistent allergic rhinitis and passive smoke exposure exacerbates this effect. We further demonstrate an association between higher sNOX2-dp and oxidative stress and endothelial dysfunction.

Gut-derived lipopolysaccharides increase post-prandial oxidative stress via Nox2 activation in patients with impaired fasting glucose tolerance: effect of extra-virgin olive oil

PURPOSE

Post-prandial phase is characterized by enhanced oxidative stress but the underlying mechanism is unclear. We investigated if gut-derived lipopolysaccharide (LPS) is implicated in this phenomenon and the effect of extra virgin olive oil (EVOO) in patients with impaired fasting glucose (IFG).

METHODS

This is a randomized cross-over interventional study including 30 IFG patients, to receive a lunch with or without 10 g of EVOO. Serum LPS, Apo-B48, markers of oxidative stress such as oxidized LDL (oxLDL) and soluble Nox2-derived peptide (sNox2-dp), a marker of nicotinamide-adenine-dinucleotide-phosphate oxidase isoform Nox2 activation, and plasma polyphenols were determined before, 60 and 120 min after lunch.

RESULTS

In patients not given EVOO oxidative stress as assessed by sNox2-dp and oxLDL significantly increased at 60 and 120 min concomitantly with an increase of LPS and Apo-B48. In these patients, changes of LPS were correlated with Apo-B48 (Rs = 0.542, p = 0.002) and oxLDL (Rs = 0.463, p = 0.010). At 120 min, LPS (β - 15.73, p < 0.001), Apo-B48 (β - 0.14, p = 0.004), sNox2-dp (β - 5.47, p = 0.030), and oxLDL (β - 42.80, p < 0.001) significantly differed between the two treatment groups. An inverse correlation was detected between polyphenols and oxLDL (R - 0.474, p < 0.005). In vitro study showed that LPS, at the same concentrations found in the human circulation, up-regulated Nox2-derived oxidative stress via interaction with Toll-like receptor 4.

CONCLUSIONS

Post-prandial phase is characterized by an oxidative stress-related inflammation potentially triggered by LPS, a phenomenon mitigated by EVOO administration.

Severity of OSAS, CPAP and cardiovascular events: A follow-up study

BACKGROUND

Previous studies suggested obstructive sleep apnoea syndrome (OSAS) as a major risk factor for incident cardiovascular events. However, the relationship between OSAS severity, the use of continuous positive airway pressure (CPAP) treatment and the development of cardiovascular disease is still matter of debate.

STUDY OBJECTIVES

The aim was to test the association between OSAS and cardiovascular events in patients with concomitant cardio-metabolic diseases and the potential impact of CPAP therapy on cardiovascular outcomes.

METHODS

Prospective observational cohort study of consecutive outpatients with suspected metabolic disorders who had complete clinical and biochemical workup including polysomnography because of heavy snoring and possible OSAS. The primary endpoint was a composite of major adverse cardiovascular and cerebrovascular events (MACCE).

RESULTS

Median follow-up was 81.3 months, including 434 patients (2701.2 person/years); 83 had a primary snoring, 84 had mild, 93 moderate and 174 severe OSAS, respectively. The incidence of MACCE was 0.8% per year (95% confidence interval [CI] 0.2-2.1) in primary snorers and 2.1% per year (95% CI 1.5-2.8) for those with OSAS. A positive association was observed between event-free survival and OSAS severity (log-rank test; P = .041). A multivariable Cox regression analysis showed obesity (HR = 8.011, 95% CI 1.071-59.922, P = .043), moderate OSAS (vs non-OSAS HR = 3.853, 95% CI 1.069-13.879, P = .039) and severe OSAS (vs non-OSAS HR = 3.540, 95% CI 1.026-12.217, P = .045) as predictors of MACCE. No significant association was observed between CPAP treatment and MACCE (log-rank test; P = .227).

CONCLUSIONS

Our findings support the role of moderate/severe OSAS as a risk factor for incident MACCE. CPAP treatment was not associated with a lower rate of MACCE.

Evaluation of Polygenic Determinants of Non-Alcoholic Fatty Liver Disease (NAFLD) By a Candidate Genes Resequencing Strategy

NAFLD is a polygenic condition but the individual and cumulative contribution of identified genes remains to be established. To get additional insight into the genetic architecture of NAFLD, GWAS-identified GCKR, PPP1R3B, NCAN, LYPLAL1 and TM6SF2 genes were resequenced by next generation sequencing in a cohort of 218 NAFLD subjects and 227 controls, where PNPLA3 rs738409 and MBOAT7 rs641738 genotypes were also obtained. A total of 168 sequence variants were detected and 47 were annotated as functional. When all functional variants within each gene were considered, only those in TM6SF2 accumulate in NAFLD subjects compared to controls (P = 0.04). Among individual variants, rs1260326 in GCKR and rs641738 in MBOAT7 (recessive), rs58542926 in TM6SF2 and rs738409 in PNPLA3 (dominant) emerged as associated to NAFLD, with PNPLA3 rs738409 being the strongest predictor (OR 3.12, 95% CI, 1.8-5.5, P < 0.001). A 4-SNPs weighted genetic risk score value >0.28 was associated with a 3-fold increased risk of NAFLD. Interestingly, rs61756425 in PPP1R3B and rs641738 in MBOAT7 genes were predictors of NAFLD severity. Overall, TM6SF2, GCKR, PNPLA3 and MBOAT7 were confirmed to be associated with NAFLD and a score based on these genes was highly predictive of this condition. In addition, PPP1R3B and MBOAT7 might influence NAFLD severity.

Overexpression of the Vitronectin V10 Subunit in Patients with Nonalcoholic Steatohepatitis: Implications for Noninvasive Diagnosis of NASH

Nonalcoholic steatohepatitis (NASH) is the critical stage of nonalcoholic fatty liver disease (NAFLD). The persistence of necroinflammatory lesions and fibrogenesis in NASH is the leading cause of liver cirrhosis and, ultimately, hepatocellular carcinoma. To date, the histological examination of liver biopsies, albeit invasive, remains the means to distinguish NASH from simple steatosis (NAFL). Therefore, a noninvasive diagnosis by serum biomarkers is eagerly needed. Here, by a proteomic approach, we analysed the soluble low-molecular-weight protein fragments flushed out from the liver tissue of NAFL and NASH patients. On the basis of the assumption that steatohepatitis leads to the remodelling of the liver extracellular matrix (ECM), NASH-specific fragments were in silico analysed for their involvement in the ECM molecular composition. The 10 kDa C-terminal fragment of the ECM protein vitronectin (VTN) was then selected as a promising circulating biomarker in discriminating NASH. The analysis of sera of patients provided these major findings: the circulating VTN fragment (i) is overexpressed in NASH patients and positively correlates with the NASH activity score (NAS); (ii) originates from the disulfide bond reduction between the V10 and the V65 subunits. In conclusion, V10 determination in the serum could represent a reliable tool for the noninvasive discrimination of NASH from simple steatosis.

Role of NADPH oxidase-2 and oxidative stress in children exposed to passive smoking

This study explored oxidative stress, nicotinamide adenine dinucleotide phosphate oxidase-2 (Nox2) activity and endothelial function in children exposed or not to passive smoking. Compared with controls (n=57), Nox2 activity and isoprostanes were higher in children exposed to passive smoking (n=57); conversely, nitric oxide (NO) bioavailability and flow-mediated dilation were lower in children exposed to passive smoking. A bivariate analysis showed that Nox2 activity correlated with flow-mediated dilation, NO bioavailability and isoprostanes. A multivariate analysis showed that Nox2 activity was significantly associated with serum isoprostanes and cotinine levels; flow-mediated dilation was associated with isoprostanes and carotid intima-media thickness.In children exposed to passive smoking, Nox2-derived oxidative stress is upregulated and inversely associated with impaired artery dilation.

Long-term prediction of adherence to continuous positive air pressure therapy for the treatment of moderate/severe obstructive sleep apnea syndrome

BACKGROUND

Continuous positive airway pressure (CPAP) therapy is a highly effective treatment for obstructive sleep apnea syndrome (OSAS). However, poor adherence is a limiting factor, and a significant proportion of patients are unable to tolerate CPAP. The aim of this study was to determine predictors of long-term non-compliance with CPAP.

METHODS

CPAP treatment was prescribed to all consecutive patients with moderate or severe OSAS (AHI ≥15 events/h) (n = 295) who underwent a full-night CPAP titration study at home between February 1, 2002 and December 1, 2016. Adherence was defined as CPAP use for at least 4 h per night and five days per week. Subjects had periodical follow-up visits including clinical and biochemical evaluation and assessment of adherence to CPAP.

RESULTS

Median follow-up observation was 74.8 (24.2/110.9) months. The percentage of OSAS patients adhering to CPAP was 41.4% (42.3% in males and 37.0% in females), and prevalence was significantly higher in severe OSAS than in moderate (51.8% vs. 22.1%; p < 0.001; respectively). At multivariate analysis, lower severity of OSAS (HR = 0.66; CI 95 0.46-0.94) p < 0.023), cigarette smoking (HR = 1.72; CI 95 1.13-2.61); p = 0.011), and previous cardiovascular events (HR = 1.95; CI 95 1.03-3.70; p = 0.04) were the only independent predictors of long-term non-adherence to CPAP after controlling for age, gender, and metabolic syndrome.

CONCLUSIONS

In our cohort of patients with moderate/severe OSAS who were prescribed CPAP therapy, long-term compliance to treatment was present in less than half of the patients. Adherence was positively associated with OSAS severity and negatively associated with cigarette smoking and previous cardiovascular events at baseline.

Adherence to Mediterranean Diet and Non-Alcoholic Fatty Liver Disease: Effect on Insulin Resistance

OBJECTIVES

The prevalence of cardiometabolic disorders, including non-alcoholic fatty liver disease (NAFLD), is increasing in western countries, because of changes in lifestyle and dietary habits. Mediterranean Diet (Med-Diet) is effective for cardiovascular prevention, but its relationship with NAFLD has been scarcely investigated.

METHODS

We included 584 consecutive outpatients presenting with one or more cardiovascular risk factor such as type 2 diabetes mellitus (T2DM), arterial hypertension, overweight/obesity, and dyslipidemia. Liver steatosis was assessed using ultrasonography. Med-Diet adherence was investigated by a validated semiquantitative nine-item dietary questionnaire; patients were divided into low, intermediate, and high adherence. Insulin resistance was defined by the 75th percentile of homeostasis model of insulin resistance (HOMA-IR; ≥3.8).

RESULTS

The mean age was 56.2±12.4 years and 38.2% were women. Liver steatosis was present in 82.7%, and its prevalence decreased from low to high adherence group (96.5% vs. 71.4%, P<0.001). In a multiple logistic regression analysis, hypertriglyceridemia (odds ratio (OR): 2.913; P=0.002), log (ALT) (OR: 6.186; P<0.001), Med-Diet adherence (intermediate vs. low OR: 0.115; P=0.041, high vs. low OR: 0.093; P=0.030), T2DM (OR: 3.940; P=0.003), and high waist circumference (OR: 3.012; P<0.001) were associated with NAFLD. Among single foods, low meat intake (OR: 0.178; P<0.001) was inversely significantly associated with NAFLD. In 334 non-diabetic NAFLD patients, age (OR: 1.035, P=0.025), high waist circumference (OR: 7.855, P<0.001), hypertriglyceridemia (OR: 2.152, P=0.011), and Log (ALT) (OR: 2.549, P=0.002) were directly associated with HOMA-IR, whereas Med-Diet score was inversely associated (OR: 0.801, P=0.018).

CONCLUSIONS

We found an inverse relationship between Med-Diet and NAFLD prevalence. Among NAFLD patients, good adherence to Med-Diet was associated with lower insulin resistance. Our findings suggest that Med-Diet may be a beneficial nutritional approach in NAFLD patients.

Spleen dimensions are inversely associated with lysosomal acid lipase activity in patients with non-alcoholic fatty liver disease

Fatty liver and splenomegaly are typical features of genetic lysosomal acid lipase (LAL) deficiency. No data in adult patients with non-genetic reduction of LAL activity are available. We investigate the association between spleen dimensions and LAL activity in non-alcoholic fatty liver disease (NAFLD) patients, in whom a reduced LAL activity has been reported. We include 425 consecutive patients who underwent abdominal ultrasound to evaluate hepatic steatosis and spleen dimensions. LAL activity was measured with dried blood spot method (Lalistat2). NAFLD was present in 74.1% of screened patients. Higher median spleen longitudinal diameter (10.6 vs. 9.9 cm; p < 0.001) and spleen area (SA) (32.7 vs. 27.7 cm²; p < 0.001), together with a higher and proportion of splenomegaly (17.8 vs. 5.5%, p = 0.001), are present in patients with NAFLD compared to those without. In NAFLD patients, median LAL activity is 0.9 nmol/spot/h. LAL activity is lower in 56 patients with splenomegaly, as compared to those without (p = 0.009). At multivariable logistic regression analysis, age (above median, OR 0.344; p = 0.003), LAL activity (below median, OR 2.206, p = 0.028), and platelets (OR 0.101, p = 0.002) are significantly associated with splenomegaly. NAFLD patients disclose a relatively high prevalence of spleen enlargement and splenomegaly, which are significantly associated with a reduced LAL activity, suggesting that LAL may contribute to spleen enlargement in this setting.

PNPLA3 variant and portal/periportal histological pattern in patients with biopsy-proven non-alcoholic fatty liver disease: a possible role for oxidative stress

Pathogenesis of non-alcoholic fatty liver disease (NAFLD) is influenced by predisposing genetic variations, dysmetabolism, systemic oxidative stress, and local cellular and molecular cross-talks. Patatin-like phospholipase domain containing 3 (PNPLA3) gene I148M variant is a known determinant of NAFLD. Aims were to evaluate whether PNPLA3 I148M variant was associated with a specific histological pattern, hepatic stem/progenitor cell (HpSC) niche activation and serum oxidative stress markers. Liver biopsies were obtained from 54 NAFLD patients. The activation of HpSC compartment was evaluated by the extension of ductular reaction (DR); hepatic stellate cells, myofibroblasts (MFs), and macrophages were evaluated by immunohistochemistry. Systemic oxidative stress was assessed measuring serum levels of soluble NOX2-derived peptide (sNOX2-dp) and 8-isoprostaglandin F_2α (8-iso-PGF_2α). PNPLA3 carriers showed higher steatosis, portal inflammation and HpSC niche activation compared to wild-type patients. DR was correlated with NAFLD activity score (NAS) and fibrosis score. Serum 8-iso-PGF_2α were significantly higher in I148M carriers compared to non-carriers and were correlated with DR and portal inflammation. sNox2-dp was correlated with NAS and with HpSC niche activation. In conclusion, NAFLD patients carrying PNPLA3 I148M are characterized by a prominent activation of HpSC niche which is associated with a more aggressive histological pattern (portal fibrogenesis) and increased oxidative stress.

Effects of dark chocolate on endothelial function in patients with non-alcoholic steatohepatitis

BACKGROUND AND AIM

Oxidative stress plays a pivotal role in inducing endothelial dysfunction and progression from simple fatty liver steatosis (FLD) to non-alcoholic steatohepatitis (NASH). Polyphenols could reduce oxidative stress and restore endothelial function by inhibiting the nicotinamide-adenine-dinucleotide-phosphate (NADPH) oxidase isoform Nox2. The aim of this study was to assess endothelial function and oxidative stress in a population affected by simple FLD and NASH. Furthermore, we analysed the effect of high vs low content of cocoa polyphenols on endothelial function and oxidative stress in patients with NASH.

METHODS

In a cross-sectional study we analysed endothelial function, as assessed by flow-mediated dilation (FMD), and oxidative stress, as assessed by Nox2 activation, serum isoprostanes and nitric oxide bioavailability (NOx), in patients with NASH (n = 19), FLD (n = 19) and controls (n = 19). Then, we performed a randomized, cross-over study in 19 subjects with NASH comparing the effect of 14-days administration of 40 g of chocolate at high (dark chocolate, cocoa >85%) versus low content (milk chocolate, cocoa <35%) of polyphenols on FMD and oxidative stress. Compared to controls, NASH and FLD patients had higher Nox2 activity and isoprostanes levels and lower FMD and NOx, with a significant gradient between FLD and NASH. The interventional study showed that, compared to baseline, FMD and NOx increased (from 2.9 ± 2.4 to 7.2 ± 3.0% p < 0.001 and from 15.9 ± 3.6 to 20.6 ± 4.9 μM, p < 0.001, respectively) in subjects given dark but not in those given milk chocolate. A simple linear regression analysis showed that Δ (expressed by difference of values between before and after 14 days of chocolate assumption) of FMD was associated with Δ of Nox2 activity (Rs = -0.323; p = 0.04), serum isoprostanes (Rs: -0.553; p < 0.001) and NOx (Rs: 0.557; p < 0.001).

CONCLUSIONS

Cocoa polyphenols improve endothelial function via Nox2 down-regulation in NASH patients.

Low-grade endotoxemia, gut permeability and platelet activation in patients with impaired fasting glucose

BACKGROUND AND AIM

Impaired fasting glucose (IFG) is associated with an increased risk of cardiovascular disease but the underlying mechanisms are still unclear. Aim of the study was to investigate the interplay between platelet activation, lipopolysaccharides (LPS) and markers of oxidative stress in patients with IFG and control subjects.

METHODS AND RESULTS

We performed a cross-sectional study including 35 patients with IFG and 35 control subjects who were well comparable for age, sex, body mass index and smoking history. Serum levels of LPS, zonulin (a marker of gut permeability), oxidized LDL and plasma levels of soluble P-selectin, were measured. Patients with IFG had significantly higher levels of sP-selectin, LPS, zonulin and oxLDL compared to control subjects. The IFG status (beta coefficient: 0.518, p < 0.001), higher LPS (beta coefficient: 0.352, p = 0.001) and female sex (beta coefficient: 0.179, p = 0.042) were independently associated with higher sP-selectin; in addition, oxLDL was positively associated with sP-selectin (r = 0.530, p < 0.001) and LPS (r = 0.529, p = 0.001). In IFG patients, we found a significant association between LPS and zonulin (r = 0.521, p = 0.001); this association was confirmed at multivariable analysis (beta coefficient: 0.512, p = 0.007).

CONCLUSION

Our study provides evidence that patients with IFG have increased platelet activation, and suggests LPS as a potential trigger for in vivo platelet activation in this patient population.