In type 1 diabetes, lack of insulin leads to increased levels of which metabolic substrate, contributing to metabolic changes?

In type 1 diabetes, lack of insulin leads to increased levels of which metabolic substrate, contributing to metabolic changes?

• A. Glucose
• B. Ketones
• C. Fatty acids
• D. Ammonia

Answer: (C)

Lack of insulin lets hormone-sensitive lipase in adipose tissue run unchecked, causing rapid lipolysis and a surge of free fatty acids in the blood. These fatty acids become the fuel source for the liver and are converted into ketone bodies, which accumulate and drive the metabolic changes seen in type 1 diabetes (such as acidosis). So, the increased substrate is fatty acids. Ketone bodies also rise as a downstream result, but the primary increase is in fatty acids fueling that ketogenesis. Glucose rises too, but it’s not the substrate driving these metabolic changes, and ammonia isn’t a major factor here.

Lack of insulin lets hormone-sensitive lipase in adipose tissue run unchecked, causing rapid lipolysis and a surge of free fatty acids in the blood. These fatty acids become the fuel source for the liver and are converted into ketone bodies, which accumulate and drive the metabolic changes seen in type 1 diabetes (such as acidosis). So, the increased substrate is fatty acids. Ketone bodies also rise as a downstream result, but the primary increase is in fatty acids fueling that ketogenesis. Glucose rises too, but it’s not the substrate driving these metabolic changes, and ammonia isn’t a major factor here.