An effect of diabetes. Insulin-dependent diabetes is often...

Name: Problem 22, Chapter 27: Biochemistry
Uploaded: 2020-07-27T23:21:30-08:00
Duration: 2 min 22 s
Channel: Jessica Honkomp
Description: An effect of diabetes. Insulin-dependent diabetes is often accompanied by hypertriglyceridemia, which is an excess blood level of triacylglycerols in the form of very low density lipoproteins. Suggest a biochemical explanation.

An effect of diabetes. Insulin-dependent diabetes is often accompanied by hypertriglyceridemia, which is an excess blood level of triacylglycerols in the form of very low density lipoproteins. Suggest a biochemical explanation.

Key Concepts

Insulin Regulation of Lipid Metabolism

Insulin plays a key role in balancing carbohydrate and lipid metabolism. It inhibits the breakdown of stored fats in adipose tissue while promoting the uptake and utilization of glucose in muscles and other tissues, thereby indirectly reducing the release of free fatty acids into the bloodstream. In the context of insulin deficiency, this regulatory mechanism is compromised, leading to an imbalance in lipid metabolism.

Adipose Tissue Lipolysis

Lipolysis refers to the breakdown of triacylglycerols in adipose tissue into free fatty acids and glycerol. Normally under the influence of insulin, lipolysis is kept in check to maintain lipid homeostasis. However, in the absence of sufficient insulin action, increased lipolysis occurs, resulting in an excess release of free fatty acids into the circulation.

Hepatic VLDL Synthesis

The liver takes up the excess free fatty acids released from adipose tissue and uses them as substrates to synthesize very low density lipoproteins (VLDL), which are responsible for transporting triacylglycerols. Elevated flux of free fatty acids to the liver leads to an increase in the production and secretion of VLDL, contributing to hypertriglyceridemia.

Lipoprotein Lipase Activity

Lipoprotein lipase is an enzyme critical for the hydrolysis of triacylglycerols in circulating lipoproteins. Insulin normally increases the synthesis and activity of lipoprotein lipase, facilitating the clearance of VLDL and chylomicrons from the bloodstream. In conditions of reduced insulin activity, the diminished lipoprotein lipase activity results in slower clearance of circulating VLDL, further exacerbating hypertriglyceridemia.

Transcript

Please give Ace some feedback