Energy Metabolism Enzymes in Adipose Tissue and in Muscle in Obesity

Abstract

In 14 adults with different body weight (10 obese subjects and 4 controls) bioptic specimens of skeletal muscle (m. quadriceps femoris) were taken and from the same region also specimens of adipose tissue under basal conditions (in obese subjects on a diet providing 2100 Kcal/day) and after weight reduction (on average by 13.7 kg) following repeated cycles of 5-days fasting with subsequent realimentation on a diet of 5-days fasting with subsequent realimentation on a diet providing 500 Kcal/day.

In the tissue specimens enzymes representing different sections of the energy metabolism were estimated: hexokinase (HK), glycerol phosphate dehydrogenase (GPDH), triose phosphate dehydrogenase (TPDH), lactic dehydrogenase (LDH), citrate synthase (CS), malate dehydrogenase (MDH) and hydroxyacyl CoA dehydrogenase (HOADH).

In adipose tissue the assessed enzyme activities were by several orders lower than in muscle with the exception of HK where the values in adipose tissue are about 80% of those in muscle. After weight reduction by 13.7 kg in adipose tissue a marked decline (by more than 50%) of HK, TPDH, LDH and MDH activities was noted (an insignificant increase was observed in HOADH), In muscle only the HK activity declined significantly.

Key words

Energy Metabolism Enzymes - Adipose Tissue - Muscle Obesity