Impact of Sex in the Effect of Dietary Capsaicin on Cardiovascular Health

Impact of Sex in the Effect of Dietary Capsaicin on Cardiovascular Health: A Randomized Controlled Trial

The investigators long-term goal is to better understand novel interventions to promote cardiovascular health in humans. The goal of the proposed research is to investigate whether there is sex-specificity in the effects of dietary capsaicin on mechanisms regulating nitric oxide (NO) bioavailability, its effect on key markers of cardiovascular (CV) health, including BP, macro- and microvascular function, and arterial stiffness. This knowledge will provide critical insight into the effects of dietary capsaicin on CV health and will guide future trials.

Study Overview

• Status: Recruiting
• Conditions: Hypertension; Pre Hypertension
• Intervention / Treatment: Dietary supplement: Dietary capsules

Detailed Description

Specific Aim 1: Determine the sex-specific effects of dietary capsaicin on central and peripheral blood pressure and arterial stiffness. The investigators hypothesize that dietary capsaicin intervention (6 week) will improve BP and arterial stiffness, likely in a sex-dependent manner. The investigators will measure heart rate variability and excretion of capsaicin and metabolites to ascertain bioavailability, and understand the mechanistic role of the autonomic nervous system, in capsaicin's effect on BP.

Specific Aim 2: Assess whether dietary capsaicin effects on vascular function is sex-specific. The investigators hypothesize that dietary capsaicin intervention (6 week) will improve NO bioavailability, through improved redox balance and lowered asymmetric dimethylarginine, thereby improving peripheral vascular function, likely in a sex-dependent manner.

Utilizing a double-blind, randomized, placebo-controlled, design the investigators will investigate whether there is sex-specificity in the effects of a 6-week dietary capsaicin intervention on nitric oxide (NO) bioavailability, BP, vascular function, and arterial stiffness.

• Study Type: Interventional
• Enrollment (Estimated): 80
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Stephen Ives, PhD; Phone Number: 5185808366; Email: sives@skidmore.edu

Study Locations

• United States
  • New York
    • Saratoga Springs, New York, United States, 12866
      • Recruiting
      • Skidmore College
      • Contact: Stephen Ives, Ph.D.; Phone Number: 518-580-8366; Email: sives@skidmore.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• relatively healthy (other than elevated blood pressure) non-smoking men and women over the age of 18 from the local community

Exclusion Criteria:

• Women who are without a period (not due to a birth control method, intrauterine device or menopause), are pregnant, attempting to conceive, or are breastfeeding will be excluded.
• uncontrolled hypertension
• Anyone with severe illness or compromised or suppressed immune system (e.g. taking immune suppressants, chronic viral infection or treatment).
• Any participants with excessive sensitivity to spicy foods or fiber (psyllium husk) will be excluded
• Participants with food allergies will be excluded
• Participants who have difficulty swallowing or swallowing pills may be excluded.
• Participants who suffer from heartburn, hiatal hernia, gastritis, or peptic ulcer disease may be excluded.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Placebo; The placebo will be 2 x 400-500 mg fiber (800 mg psyllium husk) capsules which were chosen to be of similar appearance (size, coloration, and texture).	Dietary supplement: Dietary capsules; Daily doses of dietary capsaicin or placebo in capsule form
Experimental: Dietary Capsaicin; Over-the-counter dose of 2 x 440 mg capsules (880 mg, Capsicum Pepper Blend, Daily Manufacturing, Rockwell, North Carolina, USA)	Dietary supplement: Dietary capsules; Daily doses of dietary capsaicin or placebo in capsule form

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Blood Pressure and Vascular Stiffness	The investigators will assess peripheral and estimated central blood pressures and vascular stiffness using pulse wave analysis.	Baseline, 24 hours, and 6-weeks
Heart Rate (HR) and HR variability (HRV)	The investigators will assess HR and HRV using electrocardiogram and standard techniques to determine time and frequency domain estimates of HRV.	Baseline, 24 hours, and 6-weeks
Flow Mediated Dilation	The investigators will assess brachial artery flow-mediated dilation using ischemia-reperfusion and ultrasound doppler to assess the dilatory capacity and reactive hyperemia.	Baseline, 24 hours, and 6-weeks
Passive Leg Movement Hyperemia	The investigators will assess the hyperemic response to passive leg movement using ultrasound doppler.	Baseline, 24 hours, and 6-weeks
Near Infrared Spectroscopy (NIRS) Vascular Occlusion Test	The investigators will assess the metabolic capacity and vascular reactivity using ischemia-reperfusion and NIRS	Baseline, 24 hours, and 6-weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Urinary Capsaicinoids	The investigators will collect urine to determine urinary capsaicin and associated metabolites to understand bioavailability and potential relation to function.	Baseline, 24 hours, and 6-weeks
Blood Lipids	The investigators will collect blood to determine blood lipids (cholesterol) and glucose.	Baseline and 6-weeks

Collaborators and Investigators

• Sponsor: Skidmore College
• Collaborators: American Heart Association

Study record dates

Study Major Dates

• Study Start (Actual): July 8, 2024
• Primary Completion (Estimated): December 1, 2025
• Study Completion (Estimated): December 31, 2025

Study Registration Dates

• First Submitted: April 9, 2024
• First Submitted That Met QC Criteria: April 9, 2024
• First Posted (Actual): April 12, 2024

Study Record Updates

• Last Update Posted (Actual): July 10, 2024
• Last Update Submitted That Met QC Criteria: July 8, 2024
• Last Verified: July 1, 2024

More Information

Terms related to this study

• Keywords: blood pressure; vascular function; vascular stiffness
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Hypertension; Prehypertension
• Other Study ID Numbers: 2402-1139

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Only deidentified data may be shared with the sponsor or research community through appropriate data repositories.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No