Η μη αλκοολική λιπώδης διήθηση του ήπατος αποτελεί την πιο συχνή χρόνια ηπατική νόσο στις ανεπτυγμένες χώρες. Η παχυσαρκία συνυπάρχει στην πλειοψηφία των ασθενών με μη αλκοολική λιπώδη διήθηση του ήπατος, αποτελώντας ισχυρό παράγοντα κινδύνου. Πλήθος μελετών τονίζει τον καθοριστικό ρόλο του οξειδωτικού στρες στην εμφάνιση και στην εξέλιξη της νόσου
Non alcoholic fatty liver disease (NAFLD) is the most common liver disease in Western countries. Obesity is present in the majority of individuals with NAFLD, as an independent risk factor. Recent studies emphasize the role of oxidative stress in the development and progression of NAFLD. Αim :The aim was to evaluate the prevalence of primary NAFLD in Greek overweight and obese subjects. We investigated oxidative stress in NAFLD patients by not widely used plasma oxidative stress-related parameters, a modified PAB assay and plasma protein carbonyl content. We estimated the correlations of dietary intake with oxidative stress and NAFLD. Subjects and Methods: A cross-sectional study of overweight or obese (BMI>25 Kg/m2 and ≥30 kg/m2 respectively) subjects attending the Metabolic diseases Unit B’ Medical Clinic Aristotle University of Thessaloniki “Ippokration Hospital”. Each participant underwent an abdominal ultrasound, an anthropometric evaluation and biochemical tests. The PAB and plasma protein carbonyl content were measured. Dietary habits were also evaluated in these patients. Individuals with a known etiology for secondary NAFLD were excluded. Results: 74 subjects (87.8% women, mean age 51.53±10.5) met the inclusion criteria. The prevalence of primary NAFLD was 33.3% in overweight and 67.7% in obese subjects. NAFLD was associated with higher prevalence of metabolic syndrome (p=0.034), higher systolic and diastolic blood pressure (p=0.01 and p=0.004 respectively), higher total cholesterol (p=0.05), triglycerides (p= 0.02), SGPT (p=0.00), γ-GT (p=0.005), insulin (p=0.02) and insulin resistance, measured by ΗΟΜΑ-IR (p=0.01). Variables associated with fatty liver in univariate analysis and after adjustment for sex and age were metabolic syndrome (OR: 3.801, 95%CI: 1.282-11.268), insulin resistance (ΗΟΜΑ >3.49%) (OR: 7.742, 95%CI1.484-40.39), low HDL-cholesterol (female<50mg/dl, male<40mg/dl (OR: 3.36, 95%CI: 1.173-9.626). There was no statistically significant difference among subjects with and without NAFLD ino verall calorie intake and diet composition, even after adjustment for total energy intake. A significant increase of the PAB value was noted in patients with NAFLD (147.37±34.26 ΗΚ) in comparison with the healthy group (121.51±16.5 ΗΚ), (p=0.014). Plasma protein carbonyl content did not differ significantly between the two groups (2.64±0.91 nmol /mg protein and 2.79±0.75 nmol /mg protein, p=0.624). PAB correlated with systolic and diastolic blood pressure (r=0.245, p=0.033 and r=0.28, p=0.014 respectively), total cholesterol (r=0.254, p=0.029) triglycerides (r=0.459, p=0.000), and negatively with HDL-C (r=-0.307, p=0.008). It was also observed a positive correlation in vitamin D (r=0.274, p=0.018), iron(r=0.256, p=0.028), and PAB, and a negative correlation with zinc (r=-0.35, p=0.006), copper (r=-0.235, p=0.044), phosphorus (r=-0.36, p=0.002) and PAB. In NAFLD patients, PAB strongly correlated positively with uric acid (r=0.46, p=0.001), triglycerides (r=0.394, p=0.007) and negatively with HDL-cholesterol (r=-0.375, p=0.007), vitamin Β12 (r—0.34, p=0.021), vitamins C and Ε (r=-0.32, p=0.021, r=0.323, p=0.028). Conclusions: Greek obese subjects exhibit a high prevalence of NAFLD. Metabolic syndrome, insulin resistance, low HDL-C and high level of SGPT and γGT are independently associated with NAFLD. 9 The present study shows that increased oxidative stress occurs in patients with NAFLD. PAB could be a systematic marker of oxidative stress in NAFLD. Our data suggests a possible protective role of dietary micronutrients against oxidative stress. Further larger prospective studies are needed to confirm our results.