Is Brain Insulin Resistance a Feature of the Biology of Depression in Adolescents

What Was Tested

The trial (not phased) is built around Insulin Lispro for insulin resistance, prediabetes & type 2 diabetes.

This study will examine if brain insulin resistance is a feature of depression in humans using magnetic resonance imaging (MRI) measures sensitive to brain insulin action.

It had 1 arm (groups): Crossover: Insulin and Placebo (experimental).

The registry classes the interventions as drug.

More on the Plan

In a single-blinded crossover design, all 24 participants will undergo fasting blood work (glucose, insulin, and c-peptide) followed by an MRI-based protocol of brain insulin action.

This protocol leverages the property of intranasal insulin to induce resting state connectivity and blood flow changes in the brain.

This will be achieved using a 3 Tesla (3T) MRI scanner, where participants will undergo a high-resolution T1-weighted structural scan, a resting state functional MRI scan, and an arterial spin labeling scan.

Single voxel 1H-magnetic resonance spectroscopy will also be employed to examine changes in glutamate levels in the frontal and temporal cortex.

Who Took Part

The registry lists 24 actual participants took part.

It was open to people of any sex aged from 14 years up to 18 years.

Healthy volunteers could join, not only people with the condition.

Examples of who could join: Age 14- 18. BMI between 5-95th population percentile and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) ≤2.5 calculated using fasting blood work values (glucose and insulin).

The full record lists 3 inclusion and 12 exclusion criteria; among the exclusions: history of primary psychotic illness; use of antipsychotics or mood stabilizers; history of current substance use disorder (moderate to severe).

How the Study Was Run

The set-up was sequential and open-label.

Everyone knew when Insulin Lispro was being given (open label), which is simpler to run but leaves more room for expectations to affect what is reported.

It started in 2021-09-01 with completion listed for 2025-05-13.

It ran at 1 site in Canada.

Its stated primary purpose is basic science.

What Was Measured

It also tracked 2 secondary outcomes, for example Correlation between brain insulin resistance with illness severity and cognitive functioning at baseline and 6-month study follow up and Correlation between brain insulin resistance with cognitive functioning at baseline and 6-month study follow up.

What This Means in Plain Language

Put simply, this is a not phased trial of Insulin Lispro in 24 people with insulin resistance, prediabetes & type 2 diabetes.

Its size is small, so on its own it can only give an early look.

The trial is marked completed; no results are posted to the registry yet, so nothing here describes outcomes.

More context: the Insulin Lispro compound page, Insulin resistance, prediabetes & type 2 diabetes research.