The effects of palm oil tocotrienol-rich fraction supplementation on biochemical parameters, oxidative stress and the vascular wall of streptozotocin-induced diabetic rats.

Abstract

OBJECTIVE:

This study examined the effects of palm oil tocotrienol-rich fractions on streptozotocin-induced diabetic rats.

METHODS:

Animals were divided into three groups: (i) normal non-diabetic (NDM), (ii) diabetic treated (tocotrienol-rich fractions - TRF) and (iii) diabetic untreated (non-TRF). The treatment group received oral administration of tocotrienol-rich fractions (200 mg/kg body weight) daily for eight weeks. The normal non-diabetic and the diabetic untreated groups were fed standard rat feed. Blood glucose and lipid profiles, oxidative stress markers and morphological changes of the thoracic aorta were evaluated.

RESULTS:

Tocotrienol-rich fractions treatment reduced serum glucose and glycated hemoglobin concentrations. The tocotrienol-rich fractions group also showed significantly lower levels of plasma total cholesterol, low-density lipoprotein cholesterol, and triglyceride, as compared to the untreated group. The tocotrienol-rich fractions group had higher levels of high-density lipoprotein cholesterol, as compared to the untreated group. Superoxide dismutase activity and levels of vitamin C in plasma were increased in tocotrienol-rich fractions-treated rats. The levels of plasma and aorta malondealdehyde + 4-hydroxynonenal (MDA + 4-HNE) and oxidative DNA damage were significant following tocotrienol-rich fractions treatment. Electron microscopic examination showed that the normal morphology of the thoracic aorta was disrupted in STZ-diabetic rats. Tocotrienol-rich fractions supplementation resulted in a protective effect on the vessel wall.

CONCLUSION:

These results show that tocotrienol-rich fractions lowers the blood glucose level and improves dyslipidemia. Levels of oxidative stress markers were also reduced by administration of tocotrienol-rich fractions. Vessel wall integrity was maintained due to the positive effects mediated by tocotrienol-rich fractions.

• Authors: Siti Balkis Budin, Faizah Othman, Santhana Raj Louis, Mokhtar Abu Bakar, Srijit Das, Jamaludin Mohamed
• Journal: Clinics (Sao Paulo, Brazil) (Clinics (Sao Paulo)) Vol. 64 Issue 3 Pg. 235-44 ( 2009) ISSN: 1980-5322 [Electronic] United States
• PMID: 19330251 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antioxidants
• Blood Glucose
• Plant Oils
• Tocotrienols
• Palm Oil
• Streptozocin
• Cholesterol

Topics

• Animals
• Antioxidants (administration & dosage)
• Aorta, Thoracic (drug effects, ultrastructure)
• Blood Glucose (drug effects)
• Cholesterol (blood)
• Diabetes Mellitus, Experimental (blood, pathology)
• Dietary Supplements
• Male
• Microscopy, Electron, Transmission
• Muscle, Smooth, Vascular (drug effects, ultrastructure)
• Oxidative Stress (drug effects)
• Palm Oil
• Plant Oils (administration & dosage)
• Rats
• Rats, Sprague-Dawley
• Streptozocin
• Tocotrienols (administration & dosage)