Question

Which of the following is seen in low insulin: glucagon ratio?

• A. Activation of lipoprotein lipase
• B. Activation of glycogen synthase
• C. Activation of phosphofructokinase 1
• D. Activation of hormone-sensitive lipase

Answer 1

The Correct Option is D

In biochemistry, the insulin to glucagon ratio plays a significant role in the regulation of various metabolic pathways. A low insulin to glucagon ratio is typically associated with a fasting or starvation state. In this condition, the body prioritizes the mobilization of stored energy reserves to maintain blood glucose levels. Here is an analysis of the options provided:

• Activation of lipoprotein lipase: This enzyme is primarily involved in the hydrolysis of triglycerides in lipoproteins into free fatty acids and monoglycerides. This process is upregulated by insulin, not glucagon.
• Activation of glycogen synthase: This enzyme is responsible for glycogen synthesis, which is promoted by insulin. Thus, it is more active when the insulin to glucagon ratio is high.
• Activation of phosphofructokinase 1: This is a key regulatory enzyme in glycolysis. Its activity is stimulated by insulin; hence, it is not typically activated in a low insulin to glucagon scenario.
• Activation of hormone-sensitive lipase: This enzyme is crucial for the mobilization of stored fats. It breaks down stored triglycerides into free fatty acids and glycerol under conditions where glucagon predominates, such as fasting or low insulin states. As such, it is directly activated in low insulin to glucagon ratios.

Given the analysis above, Activation of hormone-sensitive lipase is the correct choice, as it is directly upregulated in conditions characterized by low insulin to glucagon ratios to promote fat breakdown and energy mobilization.