Reduced levels of peroxisomal enzymes in the kidney of the genetically obese (ob/ob) mouse. Contrast with liver.

Kidney post-nuclear supernatants from genetically lean and obese mice were subjected to subcellular fractionation by dual centrifugation through sucrose gradients in B XIV zonal rotors. Considerable purification of peroxisomes was achieved which allowed the demonstration of acyl-CoA beta-oxidation enzymes and carnitine acyltransferases in these organelles. Comparison of kidney peroxisome-enriched fractions from obese and lean mice indicated a likely relative depression in beta-oxidation enzymes in the obese animal. Measurement of catalase, acyl-CoA oxidase and carnitine octanoyltransferase in whole homogenate of liver and kidney of obese and lean mice revealed significantly reduced levels (to approximately 2/3) of these peroxisomal enzymes in the kidney of ob/ob mice. In contrast the specific activity of catalase and acyl-CoA oxidase was significantly raised in the liver of obese mice.