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Isolation of Primary Mouse Hepatocytes for Nascent Protein Synthesis Analysis by Non-radioactive L-azidohomoalanine Labeling Method
Published on: October 23, 2018
Circulating alanine disposal in diabetes mellitus.
Diabetes
|April 1, 1978
Summary
In diabetes, the body produces more glucose, and glycogen is the likely main source. Fasting affects how the body uses alanine for glucose, but diabetes has a more significant impact.
Area of Science:
- Metabolism and Endocrinology
- Biochemistry
Background:
- Diabetes mellitus is characterized by hyperglycemia, but the precise source of excess circulating glucose remains debated.
- Alanine serves as a key circulating glucose precursor, making it a valuable marker for studying glucose metabolism.
Purpose of the Study:
- To investigate the source of excess circulating glucose in diabetes mellitus.
- To examine the role of alanine in glucose production and metabolism across different diabetes severities and in healthy individuals.
Main Methods:
- Infusion of U-14C labeled alanine and glucose in healthy subjects and patients with mild, severe, and juvenile diabetes.
- Comparative metabolic studies were conducted after a 24-hour fast in healthy and mildly diabetic subjects.
Main Results:
- Alanine production rates were stable regardless of fasting or diabetes status.
- Glucose production rates increased with diabetes severity but were unaffected by fasting.
- The contribution of alanine to glucose production (glucose-from-alanine) was significantly reduced in all diabetic groups compared to healthy controls.
- Fasting increased the conversion of alanine to glucose, while diabetes altered this relationship differently based on type.
Conclusions:
- The findings suggest that glycogen is the principal source of excess circulating glucose in diabetes mellitus.
- The study highlights altered alanine metabolism in diabetes, with implications for understanding glucose homeostasis.
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