Blood-Pressure-Lowering Effect of Glycosaminoglycan Derived From Isaria sinclairii in Spontaneously Hypertensive Rats

Abstract

The antihypertensive effects of both extracts and glycosaminoglycan derived from Isaria sinclairii (IS) were investigated in a spontaneously hypertensive rat (SHR) model. Groups of rats were treated orally with 30 mg/kg each of: (1) saline control or extracts of (2) water-IS (3) methanol-IS, (4) butanol-IS, (5) ethyl acetate-IS, or (6) captopril as positive control. The 30-mg/kg dose was administered with a standard diet every day for a period of 2 wk. The antihypertensive effects of the individual extracts were in the following order: methanol > water > ethyl acetate > butanol. Glycosaminoglycan (GAG) obtained from IS as a water-soluble alcohol precipitation fraction produced an antihypertensive effect. One month following administration of GAG derived from IS to SHR animals there was a marked decrease in systolic blood pressure from 183 to 105 mm Hg and reduced diastolic blood pressure from 148 to 80 mm Hg compared to untreated control SHR rats. It was found that GAG produced an antihypertensive effect, which was more effective than the positive control captopril. In the SHR animal model a fall of 19% in body weight was observed in the group that received GAG. Data thus indicate that GAG derived from I. sinclairii may be a potent, naturally occurring antihypertensive agent.

SHR (Spontaneously Hypertensive Rat); WKY (Wistar Kyoto Rat); glycosaminoglycan (GAG); I. sinclairii (IS); ISMC30: I. sinclairii methanol extract 30 mg/kg; ISG2: I. sinclairii glycosaminoglycan 2 mg/kg; IS GAG: I. sinclairii glycosaminoglycan.

This study was supported by the Rural Development Administration, Basic research project Pj006642 (2009–2012).

Notes

This study was supported by the Rural Development Administration, Basic research project Pj006642 (2009–2012).