Objective: 

Hypobaric hypoxia has been recently associated with various effects over brain tissue. We aimed to evaluate the effect of acute hypobaric hypoxia (HH) exposure on oxidative stress in the brain. We also tested the protective effects of a recently described natural grape seed extract (Burgund Mare, Recas –Romania-(BMR)) against HH consequences.

Methods: 

Forty-nine Wistar rats (180±20 g) were used. 7 equal groups (n=7) were constructed. Each group was exposed to one of the following: 1) no intervention; 2) 24 hours of HH (baric chamber, 5500 m, 24 hrs); 3)5 days of similar HH; 4) 24 hour HH exposure, followed 3 i.p. injections (2, 24 and 72 hrs. post HH exposure) of carboxymethyl cellulose(CMC) (0.5 ml, 0.5% sol.4), as 24-HH hour control; 5). 5 day HH exposure followed by similar CMC injections, as 5-HH day control 6) 24 hour HH exposure, followed 3 i.p. injections (2, 24, 72 hrs. post HH exposure) of BMR (3 x 0.79 AG equivalents/kg body weight), 7) 5 days of HH followed by similar BMR injections. Oxidative stress assays (5-(and-6)-carboxy-2',7'-dichlorofluorescein diacetate(DCFDA), malon dialdehyde(MDA), protein carbonyls(PC), thiol groups(SH), Trolox equivalent of antioxidant capacity (TEAC)) were performed on brain tissue.

Results: 

Significant variations were obtained following exposure to various intensities of HH for DCFDA(p=0.02), MDA(p=0.03). BMR groups demonstrate lower levels of oxidative markers as compared to CMC(I, II).(I vs III: MDA(p=0.016); II vs IV: DCFDA(p=0.023), PC(p=0.04). No between-group-significance was obtained for SH and TEAC

Conclusions: 

HH can activate oxidative stress in brain tissue. Our results suggest that BMR seed extract might present a good potential for reducing unwanted HH effects over redox equillibium.