Tissue distribution of nicotinamide N-methyltransferase activity in lean and in diet-induced obese mice

Background: Nicotinamide N-methyltransferase (NNMT) is a novel regulator of energy metabolism in adipose tissue. NNMT expression in adipose tissue is increased in obesity. Knockdown protects mice from obesity. It is unknown however whether NNMT enzyme activity, rather than expression, is increased in obesity, and how it is distributed between tissues. Aim: We aimed to develop a non-radioactive NNMT activity assay in order to analyze tissue distribution of activity in lean and obese mice. Method: White (WAT) and brown adipose tissue (BAT), liver, muscle, lung, kidney, and heart were harvested from lean and from d…