Enzymes of citrate-cleavage pathway in liver of subjects with adult-onset diabetes.

In the liver of adult diabetics, the activity of two enzymes of the citrate-cleavage pathway was increased, the change being statistically significant for NADP-malate dehydrogenase (+ 46%, p less than 0.05) but not significant for ATP citrate-lyase (+ 55%, p greater than 0.10). The increased activity of NADP-malate dehydrogenase, together with the previously described elevation of pentose cycle dehydrogenases, suggests enhanced NADPH generation. Considering the recently proposed possibility of extramitochondrial acetyl-CoA formation by routes other than the citrate-cleavage (i.e., via cytoplasmic acetyl-CoA synthetase), our data is consistent with the occurrence of increased lipogenetic capacity.