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.
Subject(s)
Antioxidants/administration & dosage , Aorta, Thoracic/drug effects , Diabetes Mellitus, Experimental/blood , Oxidative Stress/drug effects , Plant Oils/administration & dosage , Tocotrienols/administration & dosage , Animals , Aorta, Thoracic/ultrastructure , Blood Glucose/drug effects , Cholesterol/blood , Diabetes Mellitus, Experimental/pathology , Dietary Supplements , Male , Microscopy, Electron, Transmission , Muscle, Smooth, Vascular/drug effects , Muscle, Smooth, Vascular/ultrastructure , Palm Oil , Rats , Rats, Sprague-Dawley , StreptozocinABSTRACT
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.
Subject(s)
Animals , Male , Rats , Antioxidants/administration & dosage , Aorta, Thoracic/drug effects , Diabetes Mellitus, Experimental/blood , Oxidative Stress/drug effects , Plant Oils/administration & dosage , Tocotrienols/administration & dosage , Aorta, Thoracic/ultrastructure , Blood Glucose/drug effects , Cholesterol/blood , Dietary Supplements , Diabetes Mellitus, Experimental/pathology , Microscopy, Electron, Transmission , Muscle, Smooth, Vascular/drug effects , Muscle, Smooth, Vascular/ultrastructure , Rats, Sprague-Dawley , StreptozocinABSTRACT
In the present study, the effects of alpha lipoic acid (ALA) supplementation on glycemic control and lipid profile in streptozotocin (STZ)-induced diabetic rats have been evaluated. Sprague Dawley rats were divided into nondiabetic (NDM), diabetic without supplementation (No Suppl) and diabetic with ALA groups. ALA was orally administered once a day for 8 weeks with a dose of 100 mg/kg BW. Supplementation of ALA to STZ-induced rats prevented the severe damage to the islet cells of the pancreas and lowered the plasma glucose and glycated hemoglobin (HbA1c) levels. Supplementation of ALA also suppressed the increased of total cholesterol (TC), triglycerides and low density lipoprotein-cholesterol (LDL-C) levels in the plasma of diabetic rats as well as increased high density lipoproteincholesterol (HDL-C) levels. In conclusion, this study suggest that ALA may be effective in controlling glycemic status and improving dyslipidemia in streptozotocin-induced diabetic rats and has the potential in reducing cardiovascular complications due to diabetes mellitus.
