Effects of Avocado When Added to a Meat Patty on Inflammation in Healthy Men
Avocados are naturally rich in antioxidants, or beneficial compounds, that can help prevent many diseases, like atherosclerosis (hardening of the arteries). When foods that are high in fats are eaten, certain harmful compounds can be absorbed, which can lead to atherosclerosis. One harmful compound is called malondialdehyde, or MDA. This compound can be measured in the blood and the urine after a person eats a high fat meal. Antioxidants found in herbs and spices may lower the absorption of MDA, which could help prevent the development of atherosclerosis.
This study will determine whether the beneficial compounds of avocado can reduce absorption of MDA. This will be tested by asking healthy males to eat a high fat ground beef patty with or without avocado and then measuring the amount of MDA in their blood and urine samples. Blood flow will also be measured. Healthy men have been chosen for this study because eating high fat hamburger patties can easily mimic in them the condition that causes atherosclerosis. Avocadoes are rich in antioxidiants, which have been shown in previous studies to reduce the absorption of harmful compounds, like MDA, that are formed during cooking. The results from this study may help to explain how high fat foods can be harmful to the body and how beneficial antioxidants from herbs and spices can protect the body.
This will be determined from blood and urine samples after the subjects are given two different meals: a) a plain cooked ground beef patty, and b) or avocado with a cooked ground beef patty.
|Study Design:||Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Open Label
Primary Purpose: Basic Science
|Official Title:||Hass Avocado Flesh Inhibition of Appearance of Lipid Peroxidation Products When Added to a Ground Beef Patty Consumed by Healthy Volunteers|
- Plasma [ Time Frame: 6 hours ]1. To measure plasma and urine malondialdehyde by HPLC before and over6 hours after consumption of the test burgers with or without fresh avocado added just prior to consumption.
- Insulin [ Time Frame: 6 hours ]2. To measure insulin, glucose, triglycerides, TNF-α, IL-6, IL-8, NFκB activation, nitric oxide and peripheral arterial tonometry after each test burger.
|Study Start Date:||August 2011|
|Study Completion Date:||August 2012|
|Primary Completion Date:||February 2012 (Final data collection date for primary outcome measure)|
Active Comparator: Ground Beef Patty with Avocado
Test burgers with fresh avocado added just prior to consumption
Active Comparator: Ground Beef Patty without Avocado
The Hass Avocado contains monounsaturated fat, lutein, glutathione, vitamin E, and other antioxidants. This study will determine whether avocado exerts a beneficial effect by inhibition of the absorption of malondialdehyde (MDA) which is a measure of lipid peroxidation. In a previous study, we demonstrated that spice antioxidants resulted in a 70 percent decrease in the formation of MDA during cooking and that healthy volunteers consuming burgers made with spice excreted 50 percent less MDA in their urine than subjects consuming a control burger made without spices. Since the spices were added during cooking of the burger, it was not possible to assess the effects of the antioxidants in the stomach. Foods in the stomach continue to form lipid peroxidation products during digestion and this is called the "bioreactor" function of the stomach. In the proposed study known quantities of fresh avocado will be placed on top of a burger prior to consumption to determine whether the avocado inhibits formation of MDA from cooked burger meat in the stomach. Work by Aljada et al (42) demonstrated an increase in inflammatory and oxidative markers in mononuclear cells using Western blot analysis of NFkB and NADPH oxidase subunits following a mixed high calorie meal. Considering the rich content of bioactives compounds in the avocado, we therefore selected these methods for the endpoint determinations as well in this proposed randomized, crossover study.
We will accomplish the following specific aims:
- To measure plasma and urine malondialdehyde by HPLC before and over6 hours after consumption of the test burgers with or without fresh avocado added just prior to consumption.
- To measure insulin, glucose, triglycerides, TNF-α, IL-6, IL-8, NFκB activation, nitric oxide and peripheral arterial tonometry after each test burger.
These studies will add to the evidence that antioxidants in a lipid phase can inhibit formation and/or absorption of cytotoxic lipid products such as malondialdehyde. Ultimately, a better understanding of the role of bioactive substances from plant foods such as the avocado may demonstrate the importance of plant-based antioxidants in human health.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01397071
|United States, California|
|UCLA Center for Human Nutriiton|
|Los Angeles, California, United States, 90095|
|Principal Investigator:||David Heber, MD, PhD||UCLA Center for Human Nutrition|