Insulin resistance is one of the feature of
obesity.
Fetuin A is inhibitor of
insulin receptor which belongs the family of
receptor tyrosine kinase. It has been observed that
fetuin-null mice are resistant to diet-induced
obesity and they exhibit increased
insulin sensitivity. Increased production of
reactive oxygen species is suggested to be associated with
insulin resistance. Attacks of
reactive oxygen species to
DNA results in base oxidation. Among the oxidized bases,
8-hydroxydeoxyguanosine is predominant lesion with pro-mutagenic potential. In the present study; measurement of serum levels of
fetuin A and
8-hydroxydeoxyguanosine in obese subjects (n=46) and healthy controls (n=22), and examination of the relations between these parameters and
insulin resistance have been purposed. Blood samples were taken form morbidly obese subjects after a 12 h fasting. Serum levels of
fetuin A and
8-hydroxydeoxyguanosine were measured by ELISA. Statistical analysis was performed by Mann Whitney U test and correlations were examined by Spearman correlation coefficient. Serum levels of total
cholesterol, HDL,
LDL, VLDL,
triglycerides, free T3, free T4, fasting
glucose,
c-peptide and %HbA1c in the obese group were found to be different from those in the control group. Serum level of
fetuin A was found to be higher,
8-hydroxydeoxyguanosine level was found to be lower in the morbid obese group than those in the control group.
Fetuin A was found to be positively correlated with HOMA-IR (r:0,40, P<0.05) and negatively correlated with
8-hydroxydeoxyguanosine (r:-0,52, P<0.01). No significant association was determined between body mass index and measured parameters. In conclusion, serum level of
fetuin A is high in morbidly obese subjects and is negatively associated with
8-hydroxydeoxyguanosine level in peripheral circulation.
Fetuin A may be a promising link between
insulin resistance and
obesity as well its comorbidities.