"Effect of Central Insulin Administration on Whole-body Insulin Sensitivity in Women"
Status:
Completed
Trial end date:
2021-04-30
Target enrollment:
Participant gender:
Summary
The human brain is an insulin sensitive organ. Brain insulin action modulates peripheral
insulin sensitivity in young lean men. As a underlying mechanism, the investigators
previously detected suppression of endogenous glucose production and stimulation of glucose
disappearance to peripheral tissue in response to brain insulin delivery by nasal spray.
Whether this holds true in young woman is unknown, since differences in brain insulin
response between sexes have been reported. The investigators will address this question by
combining the delivery of insulin to the brain as nasal spray with hyperinsulinemic
euglycemic clamp experiments in natural cycling women.
In the planned randomized, placebo controlled cross-over study, female participants will
undergo four hyperinsulinemic euglycemic experiments with tracer dilution, two in the first
phase and two in the second phase of their menstrual cycle. On one of the study days per
menstrual phase, subjects will receive intranasal insulin administration, on the other
placebo spray. The protocol has been successfully applied previously in men. Based on the
results of this trial, the investigators calculated a required sample size of N=10 for the
planned study in women.
These experiments will help to better understand the role of brain insulin action in a
broader sense. The results can be the basis for larger clinical trials that address the
sex-specific impact of brain insulin resistance for glucose metabolism and diabetes risk.