Improving Insulin Sensitivity by Non-invasive Brain Stimulation
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Enrollment
- 44
- Locations
- 1
- Primary Endpoint
- Peripheral insulin sensitivity
Study Overview
Brief Summary
Efforts in curing and preventing obesity and type 2 diabetes (T2D) have been elusive thus far. One reason for that is the lack of understanding of the role of the brain in the development and treatment of the disease. In recent studies, the hypothalamus was identified as part of a brain network including higher cognitive regions that is particularly vulnerable to insulin resistance. Furthermore, the central insulin response in this network predicted food craving and hunger. In this project, transcranial direct current stimulation (tDCS) is implemented as a tool to stimulate brain networks. The investigators hypothesize that stimulating the hypothalamus-cognitive network will enhance insulin sensitivity and reduce food intake, food craving and hunger. Furthermore, the project will provide the unique opportunity to investigate novel mechanisms of insulin resistance in participants who have been extensively metabolically characterized.
Detailed Description
Objectives The overarching aim of the study is to stimulate the hypothalamus-cognitive brain network to improve insulin sensitivity and eating behavior.
Specific Objectives
- Implement tDCS stimulation compared to sham stimulation in overweight and obese adults to assess the impact on eating behavior, cognition and metabolism.
- Evaluate whether 3-day non-invasive brain stimulation of the hypothalamus-cognitive network has a causal effect on metabolism.
- Evaluate whether 3-day non-invasive brain stimulation has a significant effect on brain functional connectivity and diffusion parameters.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Basic Science
- Masking
- Double (Participant, Investigator)
Eligibility Criteria
- Ages
- 20 Years to 66 Years (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •Body mass index (BMI) between 25.5 and 39.5 kg/m2
- •Age between 20 to 66 years of age
- •Waist circumference ≥ 80 cm for women, ≥ 94 cm for men
Exclusion Criteria
- •Insufficient knowledge of the German language
- •Persons who cannot legally give consent
- •Pregnancy or lactation
- •History of severe mental or somatic disorders including neurological diseases (incl. epileptic seizures)
- •Taking psychotropic drugs
- •Previous bariatric surgery
- •Acute infection within the last 4 weeks
- •Hemoglobin values less than 12g/dl for women, less than 14 g/dl for men
- •Current participation in a lifestyle intervention study or a pharmaceutical study
- •Contradictions to a MRI measurement (e.g. metal implants)
Arms & Interventions
Cathodal tDCS
Cathodal tDCS of the hypothalamus-cognitive network
Intervention: transcranial direct current stimulation (Device)
Anodal tDCS
Anodal tDCS of the hypothalamus-cognitive network
Intervention: transcranial direct current stimulation (Device)
Sham Stimulation
Double blind sham stimulation (ramp-up ramp-down stimulation will be applied in order to simulate the active condition without any further continuous administration of current)
Intervention: transcranial direct current stimulation (Device)
Outcomes
Primary Outcomes
Peripheral insulin sensitivity
Time Frame: 1 day after last intervention tDCS day
Oral glucose tolerance derived insulin sensitivity based on the Matsuda index
Caloric intake (kcal)
Time Frame: 1 hour directly after tDCS stimulation
Free-choice, ad libitum food intake from a standardized breakfast buffet. The caloric intake from fat, carbohydrates and protein will be documented.
Change in subjective feeling of hunger and food craving
Time Frame: 5 minutes before tDCS stimulation, 5 minutes after tDCS stimulation and 5 minutes after buffet
On a visual analogue scale, subjective feeling of hunger and food craving will be assessed using a questionnaire.
Secondary Outcomes
- Performance during stop-signal task(task is performed during 25-minutes tDCS stimulation)
- Food choice(task is performed immediatly after buffet)
- Functional connectivity(10 minutes functional MRI measurement performed before and after three day tDCS stimulation)
- Tastiness and healthiness rating of food stimuli(task is performed immediatly after buffet)
- Diffusion-weighted imaging(15 minutes MRI measurement performed before and after three day tDCS stimulation)