| Research Abstract |
Serum adiponectin level was measured by ELISA method. The level was higher in obese children than in controls, and was restored toward normal level by slimming. The adiponectin correlated inversely with visceral adipose tissue area and waist circumference.
Oxidaized LDL is atherogenic. Recently this can be measured directly by a commercial kit. The level was higher in obese children than in controls, and was correlated with visceral adipose tissue area, waist circumference, liver function, uric acid, triglyceride, LDL-C, apo B and apo B/A1, suggesting that this is a good marker of metabolic syndrome.
The 3T3-L1 cultured adipocytes was elicited by LPS (L), TNF-α (T) and INF-γ (I) for the induction of iNOS, while culture brown adipocytes by L and T. Forskolin and dibutyryl c-AMP attenuated the iNOS induction in 3T3-L1 cells, but enhanced it in the brown adipocytes, with parallel changes in NF-κB activity. Thus, c-AMP exerts an opposite effect in white and brown adipocytes.
In 3T3-L1 cells, TNF-α activated NE-κB dose dependently, while N acetyl cysteine inhibited the activation. This was associated with a parallel change in IL-6 secretion.
Antioxidant enzymes such as catalase, glutathione peroxidase and superoxide dismutases were induced during maturation of 3T3-L1 adipocytes, corresponding to the enhanced oxidative stress due to activation of metabolism by differentiation. TNF-α suppressed this induction, leading to the enhanced oxidative stress in the cells. Thus, TNF-α plays a central role in insulin resistance, oxidative stress and atherosclerotic process.
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