The effects of multivitamin-multimineral supplementation on the spontaneously hypertensive rat model of hypertension.

Abstract

ABSTRACT The nutraceutical industry has proliferated in recent years with the most popular form of supplementation being the multivitamin-multimineral (MVMM) supplement. In the animal health sector, supplement use has also expanded. The objective of this study was to determine the effects of MVMM supplementation, beneficial or otherwise, on the general health status of the spontaneously hypertensive rat (SHR) strain, an animal model used in hypertension research. A commercially prepared MVMM supplement was given tri-weekly via oral dosing for eight weeks to two groups of seven adult female SHR and Wistar rats. Their corresponding control groups were dosed with deionised water only. Systolic and diastolic blood pressure, fasting blood glucose, growth rate and food and water intake were measured weekly. At the end of eight weeks, the animals were euthanized and a full blood profile, urine sodium potassium ratio, blood urea nitrogen levels and total plasma cholesterol was measured for all groups. Further biochemical tests included determining plasma C-reactive protein, angiotensin-converting enzyme and kidney lipid peroxidation levels. Blood and tissue trace element profiles were determined by ICP and EDX analysis. A histological study was conducted on the kidney and aorta. MVMM supplementation had significant metabolic, cardiovascular and renal effects in the SHR group. It increased growth and caused a significant reduction in the diastolic blood pressure of both SHR S and WIS S groups over the eight week period. It also lowered total cholesterol and increased RBC count in the SHR S group. Supplementation also had some renoprotective properties as the SHR S group exhibited lesser hypertension related morphological changes in the kidney due to lowered blood pressure and possible antioxidant effects of the supplement. This was however not translated into any improvement in renal function. No adverse effects on the general health status of the animals were observed. MVMM supplementation may therefore be useful in aiding growth and delaying the onset of hypertension and the related complications. It may also assist in the longevity of the breeding stock of SHR rats.