Maitake Mushroom Extracts Ameliorate Progressive Hypertension and Other Chronic Metabolic Perturbations in Aging Female Rats
Abstract
Objective: We assessed the ability of two commercially-available fractions labeled SX and D
derived from the edible maitake mushroom to overcome many age-associated metabolic
perturbations such as progressive, age-related elevation of blood pressure, over activity of the
renin-angiotensin system (RAS), decreased insulin sensitivity, and inflammation in an in vivo
laboratory model.
Design and Method: We divided forty mature, female Sprague-Dawley rats (SD) into five
groups of eight. SD ingested regular rat chow containing added sucrose (20% w/w). The
groups received baseline diet alone (control) or baseline diet containing captopril, niacin-bound chromium, maitake fraction SX, or maitake fraction D. In addition to blood
pressure readings, the following procedures were implemented: losartan and insulin challenges, evaluation of serum ACE activity, glucose tolerance testing, blood chemistries,
LNAME challenge, and measurement of various circulating cytokines.
Results: We found that implementation of all test conditions stopped the gradual elevation of
systolic blood pressure (SBP) in the SD over the four months of study, even reversing some of
the previous elevation that occurred over time. In general, the treatment groups showed
decreased activity of the RAS estimated by less lowering of SBP after losartan challenge and
decreased serum ACE activity and were more sensitive to exogenous insulin challenge. TNFa
levels decreased in all four test groups suggesting a lessening of the inflammatory state.
Conclusions: We believe our data suggest that maitake mushroom fractions lessen
age-related hypertension, at least in part, via effects on the RAS; enhance insulin sensitivity;
and reduce some aspects of inflammation -- actions that should lead to a longer, healthier life
span.