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Updated: May 29, 2026
08:32
Studying the Hypothalamic Insulin Signal to Peripheral Glucose Intolerance with a Continuous Drug Infusion System into the Mouse Brain
Published on: January 4, 2018
Peripheral glucose homeostasis: does brain insulin matter?
Barry E Levin1, Robert S Sherwin
1Neurology Service (127C), VA Medical Center, East Orange, New Jersey 07018, USA. levin@umdnj.edu
The Journal of Clinical Investigation
|August 26, 2011
Summary
Brain insulin signaling modestly reduces hepatic glucose output in dogs. This effect, however, requires prolonged fasting and insulin exposure, questioning its physiological relevance in controlling glucose metabolism.
Area of Science:
- Neuroendocrinology
- Metabolic Regulation
- Glucose Homeostasis
Background:
- The role of brain insulin signaling in regulating hepatic glucose metabolism is controversial.
- Insulin directly inhibits glucose production in the liver.
Purpose of the Study:
- To investigate the effect of direct brain insulin infusion on hepatic glucose metabolism in dogs.
- To assess the physiological relevance of central insulin action on glucose production.
Main Methods:
- Arterial infusion of insulin into the brain of dogs.
- Measurement of net hepatic glucose output and endogenous glucose production.
- Utilized prolonged fasting and prolonged brain insulin exposure.
Main Results:
- Brain insulin infusion reduced net hepatic glucose output.
- This effect was modest and did not alter endogenous glucose production.
- The observed effect required prolonged fasting and brain insulin exposure.
Conclusions:
- Central insulin action has a modest and context-dependent role in hepatic glucose metabolism.
- The physiological significance of brain insulin signaling may be more relevant in chronic conditions like type 1 and type 2 diabetes.
- Chronic hyperinsulinemia and central insulin resistance in type 2 diabetes may highlight the importance of central insulin's role.
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