Watermelon Supplementation and Arterial Stiffness

NCT01185041 | Completed Phase 1

• 1 other identifier: RF02032
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

Increased abdominal obesity (waist circumference) and systolic blood pressure (BP) are main risk factors for the metabolic syndrome. Approximately 60% of adults in the United States are prehypertensive or hypertensive. Hypertension has been associated with abnormal endothelial and autonomic function, the two main mechanisms of BP regulation. Endothelial dysfunction, as a result of reduced NO (a vasodilator), and increased sympathetic nervous system activity contribute to arterial stiffness by enhancing the vasomotor tone. Because BP variations are sensed by baroreceptors in the wall of large arteries, increased stiffness of arteries may attenuate the control of BP by the autonomic nervous system leading to hypertension. High production of proinflammatory cytokines and low adiponectin (vascular protective molecule), are considered the underlying mechanisms leading to endothelial dysfunction and arterial stiffness. The recommended intervention for controlling BP in overweight/obese individuals with pre- and stage 1- hypertension is lifestyle modifications and not drug therapy. Among the dietary regimens that are reported to reduce BP is L-arginine, the substrate for endothelial NO production. Recently, oral L-citrulline has been shown to be more effective than L-arginine in improving circulating NO levels because is not affected by enzymatic degradation. Watermelon, the leading US melon crop, is one of the few natural foods rich in L-citrulline which is efficiently transformed to arginine in humans. The investigators long-term goal is to provide feasible and effective dietary ways to reduce cardiovascular risk factors in individuals with high abdominal fat and BP. The overall objective of this study is to bring forth evidence that watermelon supplementation will reduce BP and cardiovascular risk factors such as arterial stiffness, autonomic dysfunction and endothelial dysfunction. The investigators postulate that watermelon supplementation will reduce BP and arterial stiffness by enhancing endothelial function and reducing vascular inflammation. The findings of this study will provide a foundation for disseminating feasible, safe approaches for preventing and combating obesity-related hypertension at its early stage which does not require drug therapy.

Conditions

Hypertension

Keywords

Arterial Stiffness; Wave Reflection; Watermelon Supplementation; Aortic Blood Pressure; Obesity

Outcome Measures

Primary Outcomes (1)

• Blood Pressure

  By measuring brachial and central (aortic and carotid) BP at rest and during physiological stress (head-up tilt test and cold pressor test)

  12 weeks

Secondary Outcomes (4)

• Arterial Stiffness

  12 weeks

• Endothelial function

  12 weeks

• Autonomic control of BP

  12 weeks

• Autonomic control of heart rate

  12 weeks

Study Arms (2)

Maltodextrin

PLACEBO COMPARATOR

6g/day of placebo (maltodextrin)

Dietary Supplement: Watermelon Extract

Watermelon

EXPERIMENTAL

(6g per day)containing L-citrulline/L-arginine (4/2 g)

Dietary Supplement: Watermelon Extract

Interventions

Watermelon Extract DIETARY_SUPPLEMENT

6 weeks of watermelon extract taken in two doses of 3g each per day (6g per day)containing L-citrulline/L-arginine (4/2 g)

Also known as: Watermelon extract from Milne fruit Products Inc

Maltodextrin; Watermelon

Eligibility Criteria

• Age: 45 Years - 70 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Thirty men and women 45-70 years of age
• BP between 120-159/80-99 mmHg
• Waist circumference \>102 cm in men and \> 80 cm in women

You may not qualify if:

• BP \>160/100 mmHg
• Asthma
• Glaucoma
• Herpes simplex
• Uncontrolled diabetes
• Neurological disease
• Cardiovascular disease
• Inflammatory disease
• Kidney disease
• Hormone replacement therapy (HRT)
• Amino acid/vitamin supplementation\\
• Corticosteroids or non-steroidal anti-inflammatory drugs
• Any drug known to affect BP or heart rate
• Glycemic control drugs
• Lipids reducing drugs

Sponsors & Collaborators

• Florida State University: lead

Study Sites (1)

Cardiovascular Physiology Laboratory

Tallahassee, Florida, 32306, United States

Location

Related Publications (1)

• Figueroa A, Wong A, Kalfon R. Effects of watermelon supplementation on aortic hemodynamic responses to the cold pressor test in obese hypertensive adults. Am J Hypertens. 2014 Jul;27(7):899-906. doi: 10.1093/ajh/hpt295. Epub 2014 Feb 26.

  PMID: 24572702 DERIVED

MeSH Terms

Conditions

Hypertension; Obesity

Condition Hierarchy (Ancestors)

Vascular Diseases; Cardiovascular Diseases; Overweight; Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Arturo Figueroa, MD, PhD

  The Florida State University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Study Record Dates

• First Submitted: August 17, 2010
• First Posted: August 19, 2010
• Study Start: August 1, 2010
• Primary Completion: August 1, 2011
• Study Completion: August 1, 2011
• Last Updated: March 20, 2012

Record last verified: 2012-03

Locations

US (1)