Biochemical aspects of ketogenesis, a review

Ketogenesis occurs only under certain physiological conditions, the physiological substrate for the process being long chain fatty acids. The condition for ketogenesis arises if the long chain fatty acid levels are high enough to render the liver incapable of metabolising all the acetyl CoA, formed as a result of hepatic oxidation of long chain fatty acids, via the tricarboxylic acid cycle to yield water and carbon dioxide. The state in which unesterified fatty acid levels are high enough to cause ketogenesis can be arrived at if there is a lack of insulin or a condition of starvation. Biochemical regulation, pathological condition and relative levels of ketone bodies are also reviewed. It was found that maximum ketonemia reflects not only increased production but also decreased use. The determination of urine or plasma 3-hydroxybutyrate may be of more importance than a simple urinary test upon ketone bodies in diabetic persons