Prestroke barley beta-D-glucan supplementation protects heart and brain from consequences of ischemic stroke regardless of caloric restriction

Background: Chronic psychosocial stress (PS) and diet-induced obesity cause HBAd, yet its impact on post-stroke outcome is uncertain. 3% barley beta-D-glucan (BBG) supplementation in a high-fat diet (HFD) prevented HBAd in obese PS-exposed mice. We hypothesize that prestroke BBG dietary supplementation may protect heart and brain from stroke's severe consequences regardless of calorie restriction. Methods: MCAO was performed on adult male C57BL/6J mice with (n=8) and without (n=8) HBAd. Long-term PS exposure caused HBAd in HFD-induced obese mice. HBAd mice were administered an HFD diet with (HFD-beta, n=4) or without (HFD, n=4) 3% BBG before a stroke. Both groups got a month-long normocaloric diet without BBG after stroke. Baseline and 30-day post-stroke motor brain and heart function were assessed. Grid walking, cylinder tests, and echocardiography measured motor brain and heart function Results: HBAd mice exhibited severe stroke-induced brain injury compared to mice without HBAd. Motor recovery was significantly improved in HFD-beta mice within 30 days after MCAO, whereas heart rate was significantly reduced by 30% in both groups without changes of left ventricular systolic and diastolic function. However, heart rate was positively correlated with brain motor recovery only in treated mice. After stroke, HFD-beta had significantly lower end-diastolic interventricular septum thickness than HFD mice. Conclusions: Pre-stroke HFD BBG supplementation reduced brain ischemia damage and cardiac remodeling in mice with lowered heart rate. Our data suggest BBG supplementation of HFD is sufficient to preserve brain and cardiac function after a stroke in high-risk patients regardless subsequent caloric restriction.