Estimation of gamma-glutamyl transferase as a suitable simple biomarker of the cardiovascular risk in children with non-alcoholic fatty liver disease.

Non-alcoholic fatty liver disease (NAFLD) is a hepatic manifestation of metabolic syndrome and a risk factor for cardiovascular disease (CVD). Research conducted in adults has proven that GGT can also be an independent risk factor for CVD. The aim of this study was to ascertain if GGT can be regarded as a simple biomarker of cardiovascular risk in obese children with NAFLD. One hundred obese children, aged 7-17 years, with suspected liver pathology were admitted to our Department. Viral hepatitis and autoimmune, toxic and selected metabolic liver diseases were excluded. Anthropometry, laboratory tests, 1HMR spectroscopy and evaluation of the common carotid artery intima-media thickness (IMT) were performed in all subjects. NAFLD was confirmed in 38 obese patients. There was a significantly higher activity of GGT and ALT, the concentration of total and LDL cholesterol, waist circumference, left coronary artery IMT, mean IMT value and total lipids in 1HMRS in children with NAFLD in comparison to non-hepatopathic obese children. Logistic regression analysis indicated that GGT, total cholesterol, LDL-cholesterol, left IMT and waist circumference significantly affected the development of NAFLD in obese children. In ROC analysis only GGT, waist circumference and left IMT allowed to differentiate children with NAFLD from those without steatosis with GGT having the highest result (AUC=0.94). GGT activity in patients revealed weak or at the upper limit of statistical significance correlation with traditional cardiovascular risk factors: glucose level, waist circumference, BMI, total cholesterol, LDL-cholesterol and insulin level. This allows to suggest, that GGT might be a potential reliable, simple and non-invasive biochemical marker for estimation of cardiovascular risk in obese children with NAFLD. However, further studies on larger population are necessary to confirm that observation.

Chemerin as a novel non-invasive serum marker of intrahepatic lipid content in obese children.

BACKGROUND: Ectopic hepatic lipid accumulation is closely related to the development of insulin resistance, which is regarded as one of the most significant risk factors of non-alcoholic fatty liver disease (NAFLD). The current study has shown that fat tissue constitutes an important endocrine organ with its own production and metabolism of many biologically active substances, among which adipokines play an important role. Classic adipokines (e.g. leptin, adiponectin, resistin) are fat-derived hormones which serum level is altered in patients with NAFLD. The role of novel adipokines in the pathomechanism of this disease is not clear. Therefore, the aim of our study was to evaluate the serum concentrations of chemerin, omentin and vaspin in obese children with NAFLD. METHODS: Forty-five obese children, aged 7-17 years old, were admitted to our Department with suspected liver disease (hepatomegaly, and/or ultrasonographic liver brightness, and/or increased ALT activity). Viral hepatitides, as well as autoimmune and metabolic liver diseases were excluded. Fasting serum levels of chemerin, omentin and vaspin were determined. The grade of liver steatosis in ultrasound was graded according to Saverymuttu. (1)HMR spectroscopy was performed with a 1.5 T scanner and with PRESS sequencing. RESULTS: Fatty liver was confirmed in 39 children by ultrasound and in 33 patients by (1)HMRS (19 of them also had increased ALT activity /NAFLD/). Chemerin and vaspin levels were significantly higher in children with NAFLD compared to the control group (n = 30). The concentration of chemerin was significantly higher in children with advanced liver steatosis compared to non-hepatopathic patients (p = 0,02). Significant positive correlations were found between the total liver lipids in (1)HMRS and chemerin (r = 0,33; p = 0,02) and vaspin (r = 0,4; p = 0,006). The ability of serum chemerin (cut-off = 190 ng/ml, Se = 75%, Sp = 58%) to differentiate children with fatty liver in (1)HMRS from those without steatosis was significant (AUC = 0,7, p = 0,04). Omentin and vaspin did not allow a useful prediction to be made. CONCLUSION: Chemerin seems to be the most suitable non-invasive biomarker in predicting both intrahepatic lipid content in obese children and advanced liver steatosis in children with NAFLD.

Serum fetuin A concentration is elevated in children with non-alcoholic fatty liver disease.

PURPOSE: To assess the serum fetuin A concentration as a potential marker of subclinical atherosclerosis in obese children with NAFLD. MATERIAL/METHODS: A prospective analysis of 45 obese children initially diagnosed with liver pathology (elevated serum ALT activity and/or ultrasonographic liver brightness and/or hepatomegaly) was conducted. The diagnosis of NAFLD was established in the children with elevated serum ALT activity and liver steatosis on ultrasound examination. Viral hepatitis, autoimmune, metabolic liver diseases (Wilson disease, alpha-1-antitrypsin deficiency, cystic fibrosis) and drug and toxin-induced liver injury were excluded in all children. The degree of liver steatosis was graded according to Saverymuttu scale and the total liver lipids concentration was assessed using proton magnetic resonance spectroscopy ((1)H MRS). RESULTS: Serum fetuin A concentration was significantly higher in examined children compared to the control group (n=30) (p=0.00002). Higher serum fetuin A concentration was also observed in children with NAFLD (n=19) in comparison to the controls (p=0.000026). Additionally, higher BMI values, waist circumferences, ALT and GGT activity, intensity of liver steatosis on ultrasound and total concentration of lipids in the liver in (1)H MRS were found in children with NAFLD compared to the rest of the examined obese patients (n=26). There was not found any correlation of the investigated glycoprotein with any other assessed parameters both in children with NAFLD and obese children without NAFLD. CONCLUSION: Higher serum fetuin A concentration found in children with NAFLD compared to the control group support the hypothesis that atherosclerotic processes may develop faster in hepatopatic obese patients.