Active not recruitingNAINTERVENTIONAL

The Importance of Insulin Action in the Brain for the Immune System During Physical Activity

This study is investigating the connection between how insulin works in your brain, physical activity, and your immune system. We want to understand if brain insulin helps control your immune system when you exercise. Participants will do exercise tests on a special bike. On one day, they will use a nasal spray containing insulin, and on another day, they will use a 'dummy' spray (placebo). Scientists will then compare the results from these days to see how these different sprays affect the immune system's response during exercise. This research aims to give us a clearer picture of these important body processes.

At a glance

Status

Active not recruiting

Phase

Sponsor

University of Ulm

Enrolment target

Start

15 Dec 2024

Estimated completion

01 Sep 2026

Insulin Sensitivity

What is this study about?

This research project is all about understanding a fascinating link between how insulin works in your brain, how your body responds to exercise, and the strength of your immune system. You might know about insulin helping to control blood sugar, but it also has important roles in the brain that scientists are still learning about. We want to find out if the insulin acting in your brain actually helps to manage your immune system when you're physically active.

To do this, we'll ask volunteers to take part in some gentle exercise on a special stationary bike, called a spiroergometer. This bike helps us measure how your body uses oxygen during exercise. What makes this study unique is that we'll compare two different situations: on one day, participants will use a nasal spray that delivers insulin to the brain, and on another day, they'll use a 'dummy' spray that contains no active medicine (a placebo). By doing this, we can carefully observe the differences.

Ultimately, this study aims to shed light on how your brain's insulin system communicates with your immune system during exercise. This knowledge could be important for understanding overall health and how our bodies cope with physical challenges.

Key takeaways

Investigates how insulin in the brain affects the immune system during exercise.
Compares effects of insulin nasal spray vs. a dummy (placebo) spray.
Involves moderate exercise on a special stationary bike.
Aims to understand general body processes, not individual health improvements.
Participants will be healthy adults aged 18-30.

Who may be eligible?

To join this study, you need to be a healthy adult between 18 and 30 years old. Your body mass index (BMI) should be less than 24, which means you have a healthy weight for your height. It's also important that you don't have any major ongoing health problems, and if you take hormonal contraception, it needs to be a specific single-phase type.

There are also some reasons why you wouldn't be able to join. For example, if you smoke or have a history of alcohol or drug misuse, this study wouldn't be suitable for you. We'll also check your blood iron levels (hemoglobin) to make sure they are within a healthy range; for women, it needs to be at least 12 g/dl, and for men, at least 14 g/dl.

Finally, if a doctor thinks that taking part in this study could be unsafe for you or might affect the study results, then you wouldn't be able to participate. This is to make sure everyone involved is safe and the research is accurate.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you between 18 and 30 years old?
Do you have a healthy weight (BMI less than 24)?
Do you have any primary ongoing health conditions?
Do you smoke or misuse alcohol or drugs?
Are your blood iron levels healthy (if known)?

Answer every question to see your result.

What does participation involve?

If you decide to take part, you'll visit the research centre on a few occasions. On two separate days, you'll perform a bicycle exercise test. Before each test, you'll use a nasal spray – on one day it will contain insulin, and on the other, it will be a placebo (a dummy spray). These sprays will be given about 30 minutes before you start exercising. The bike test itself will last for 60 minutes at a moderate effort level. During the placebo day, you'll also receive a small injection of insulin into your vein to make sure the conditions are as similar as possible between the two test days.

Throughout the study, we'll take various measurements to understand how your body is responding. This will include looking at your physical performance, how your body's automatic control system (autonomic nervous system) is working, and examining your immune cells. We will also collect blood samples to study your immune cells and the chemical messengers (cytokines) they produce. The total duration of your involvement will span these two test days, plus any initial screening visits.

Potential risks and benefits

Taking part in any study has potential benefits and risks. A potential benefit of this study is contributing to scientific knowledge about how the brain, exercise, and the immune system are connected, which could help others in the future. There are no direct personal health benefits expected from participating. Risks are generally low but might include mild discomfort from exercise or temporary effects from the nasal spray or blood draws. You will be closely monitored by medical staff during the exercise tests. Remember, you can withdraw from the study at any time, for any reason, without it affecting your medical care.

Locations (1)

Universityhospital Ulm
Verified postcode
Ulm, Germany

Common questions

What is 'insulin sensitivity'?

Insulin sensitivity refers to how well your body's cells respond to insulin. It's important for managing blood sugar, but insulin also has other roles.

What is a spiroergometer test?

It's a special exercise test on a bike that measures how much oxygen your body uses, helping us understand your fitness and energy use.

What is a placebo spray?

A placebo spray looks and feels exactly like the real insulin spray but contains no active medicine. It helps us compare the effects of the actual treatment.

Will I know if I'm getting insulin or the placebo?

No, both you and the study team will not know which spray you are receiving on which day. This is called 'blinded' and helps keep the results fair.

Will this study help me personally?

This study aims to expand scientific understanding, so there are no direct personal health benefits for participants.