Effect of Supplement on Appetite and GLP-1

Study Title:

Acute Effect of Supplement Containing L-Arginine on Appetite Suppression and GLP-1 Induction

Research Objectives:

The study aims to evaluate the effects of a dietary supplement containing L-arginine, resveratrol, tart cherry, and vitamin C on appetite suppression, GLP-1 hormone release, and associated metabolic outcomes in individuals with overweight or obesity.

Background:

GLP-1 (Glucagon-Like Peptide 1) plays a crucial role in regulating appetite and glucose homeostasis.

Condensed Background Information:

The combination of the following ingredients is hypothesized to have a synergistic effect, promoting satiety and improving metabolic health:

• L-arginine enhances GLP-1 secretion, improving glucose tolerance and reducing appetite.
• Resveratrol inhibits DPP-IV, extending the activity of GLP-1.
• Tart cherry supports metabolic regulation by enhancing nitric oxide availability and preventing arginine catabolism.
• Vitamin C acts as an antioxidant, supporting the efficacy of other components.

Participant Details:

• Number of Participants: 25
• Eligibility Criteria:
• Adults aged 18-60 years.
• BMI between 25 and 40 kg/m².
• Must maintain current diet and physical activity levels.

Exclusion criteria

• Significant weight change (>5%) in the last three months.
• Medical conditions like uncontrolled diabetes, kidney disease, thyroid disorders, or autoimmune diseases.
• Current use of medications or supplements affecting weight or GLP-1 levels.
• Pregnancy or lactation.

Study Design:

This is a randomized, triple-blinded, placebo-controlled study with three conditions:

• High-Dose Supplement (~10 g)
• Low-Dose Supplement (~5 g)
• Placebo (~5 g) Each participant will experience all three conditions in random order.

The timeline for the study involves:

• Pre-Session: 8-hour fasting before each visit.
• Arrival at the lab (Rickel Building, Rooms 256/259).
• Baseline blood sample collection.
• Administration of assigned supplement/placebo.
• 60-minute rest period.
• Consumption of a standardized meal (Bertolli Chicken Alfredo pasta bake) in isolation within a 30-minute window.
• Collection of additional blood samples at eight-time points
• Measurement of hunger using a 7-point scale.

Study Procedures

Blood Sampling:

• 7 mL samples collected at each time point for metabolic analysis (e.g., glucose, insulin, GLP-1).
• Total blood volume: 168 mL per participant across all sessions.
• Samples will be analyzed for metabolic markers in Dr. Ryan Porter's lab.

Satiety Measurement:

Participants will rate hunger levels at each blood draw using a scale from "Extremely Hungry" to "Extremely Full."

Meal Intake:

An ad libitum meal is provided to assess the impact of supplementation on food consumption.

Risks and Mitigation

• Blood Draw Risks: Bruising, pain, infection, or dizziness. Managed by using trained personnel and aseptic techniques.
• Supplement Risks: Gastrointestinal discomfort and allergic reactions. Addressed by pre-screening participants for allergies. Emergency supplies will be available.
• Data Privacy Risks:

All data will be anonymized and stored securely to prevent breaches.

Expected Outcomes

The study aims to determine:

• If the supplement reduces hunger compared to a placebo.
• If it enhances GLP-1 release post-meal.
• If it improves other metabolic parameters (e.g., glucose, lipid profiles).

Data Handling:

All data will be anonymized and securely stored. Samples may be retained for up to 24 months for further research.

Statistical Analysis:

Data analysis will use ANOVA and Tukey's post-hoc tests in SPSS, with significance set at p<0.05.

Study Impact:

This research could contribute to developing effective nutritional interventions to support appetite regulation and weight management, benefiting individuals with obesity and/or metabolic disorders.

Inclusion criteria

Participants must meet all the following conditions to be eligible for the study:

• Age: 18-60 years old.
• BMI (Body Mass Index): Between 25 and 40 kg/m².
• Diet and Activity Stability: Willing to maintain current dietary and physical activity habits for the duration of the study.

Exclusion criteria

Participants will be excluded from the study if any of the following conditions apply:

• Recent Weight Change: Lost or gained more than 5% of body weight in the last 3 months.
• Pregnancy or Lactation: Pregnant or breastfeeding women.
• Medical Conditions:

• Kidney disease (Chronic Kidney Disease or End-Stage Renal Disease).
• Herpes simplex.
• Uncontrolled diabetes (HbA1c >7%).
• Thyroid disorders or taking thyroid medications.
• Type 1 diabetes.
• Cushing syndrome.
• Cirrhosis or hepatitis.
• Chronic obstructive pulmonary disease (COPD).
• Dementias.
• Active autoimmune diseases (e.g., lupus, rheumatoid arthritis).
• Crohn's disease or ulcerative colitis.
• Celiac disease.
• Allergies or Sensitivities:
• Known allergies to any components of the supplement or standardized meal.
• Medications: Currently taking any of the following:
• Supplements or medications for weight loss.
• Antihypertensive, antidiabetic, or antihyperlipidemic medications.
• Erectile dysfunction medications.
• Blood thinners (e.g., aspirin, warfarin).
• Medications containing nitric oxide or nitroglycerin.
• Drugs affecting GLP-1 levels, such as GLP-1 receptor agonists, insulin, certain antidepressants, or corticosteroids.

• Substance Use: Evidence of illegal drug use, including marijuana.
• Participation in Other Studies: Enrollment in another clinical trial that could interfere with the study outcomes.