Effect of mCPP on Cognitive Control, Appetite, and Neural Responses

• Status: Terminated
• Trial end date: 2020-03-20
• Target enrollment: 0
• Participant gender: All

Summary

Previous studies have reported that the 5-HT2C receptor agonist meta-chlorophenylpiperazine (mCPP) decreases appetite and food intake in humans1-3. 5-HT2C receptor activation inhibits dopamine and norepinephrine release in the brain4, and has also been linked to diabetes5. The specificity of the effect of mCPP on human appetite is unclear, as previous studies also reported an increase in nausea1,3. The drug has also been reported to increase anxiety and cause panic attacks when given in a bolus dose intravenously6. Previous findings in our laboratory showed that mCPP reduced appetite, increased satiety in women and enhanced memory in the P1vital® Oxford Emotional Test Battery3. Following up on these results a food intake and fMRI study was performed, in which it was observed that mCPP decreased intake of a palatable snack (hedonic eating) and dlPFC and insula BOLD responses to food pictures. Additionally it increased memory and food value responses in brain after mCPP administration (Thomas et al submitted).

It is well established that eating behaviour is affected by metabolic signals (e.g. insulin, ghrelin, serotonin) and is also modulated via food reward processes7. More recently it has been proposed that eating is also modulated via higher cognitive processes such as inhibitory control, attention, and memory. However, in humans, eating behaviour seems to be a more complex process, which involves habits, long-term goals and social interaction. Thus, cognitive processes appear to play an important role in food consumption. In the proposed study the researchers investigate the effect of administering mCPP, on eating, and on metabolic, reward and cognitive processes and the potential interplay between these functions.

• Phase: N/A
• Accepts Healthy Volunteers?: Accepts Healthy Volunteers

Details

• Lead Sponsor: University of Birmingham
• Collaborator: University Hospital Birmingham
• Treatments: 1-(3-chlorophenyl)piperazine

Criteria

Inclusion Criteria:

• Healthy female subjects

• Age 18-65 years at start of the study

• Body Mass Index (BMI) between 18 and 25 kg/m2 for the lean group and between 30 and 40 kg/m2 for the obese group

• Right-handedness (including left-handers could bias the results because of the laterality of brain functions)

• Ability to give informed consent

• Fluent English speaking

• Willingness to be informed about chance findings of pathology

Exclusion Criteria:

• Subjects who have a non-removable metal object in or at their body, such as, for example: Heart pace-maker, artificial heart valve, metal prosthesis, implants or splinters, non-removable dental braces

• Tattoos, that are older than 15 years

• Claustrophobia

• Limited temperature perception and/or increased sensitivity to warming of the body

• Pathological hearing ability or an increased sensitivity to loud noises

• Lack of ability to give informed consent

• Operation less than three months ago

• Simultaneous participation in other studies that involve drugs intake or blood spending

• Acute illness or infection during the last 4 weeks

• Cardiovascular disorders (e.g., hypertrophic cardiomyopathy, long QT syndrome)

• Moderate or severe head injury

• Eating disorders

• No metabolic (e.g. metabolic disorder, diabetes, insulin resistance), psychological (e.g. depression) or neurological (e.g. epilepsy, headache disorder, multiple sclerosis, traumatic brain injuries) diseases or medication in relation to these diseases.

• Intake of any medication that can interfere with the drug or measurements.

• Current weight loss regimens, or more then 5kg weight loss in the last 3 months

• Smoking

• Current pregnancy or breastfeeding

• Current or past history of drug or alcohol dependency - alcohol consumption exceeding 12 units a week

• Food allergies (e.g. peanut allergy lactose and gluten intolerance) or vegetarian/vegan diet

• Disliking the study lunch