Abstract 185: Whole Body Periodic Acceleration (pGz) in Mice Increases Antioxidant Enzymes in the Heart
BACKGROUND: Mild to moderate exercise produces cardio and neuroprotection. Exercise increases pulsatile shear stress that provide several cytoprotective and signaling substances from muscle and endothelium. Some beneficial effects of exercise on cytoprotection are derived from increased antioxidant capacity. pGz is a passive exercise strategy that moves the body in a sinusoidal head to foot motion, adding pulses to the circulation thereby increasing pulsatile, cyclical shear stress to the endothelium. pGz activates the PI3/Akt eNOS pathway and increases release of eNO and its enzyme (eNOS), and other cytoprotective signaling and substances, and decreases reperfusion injury. Optimum frequency of pGz has been established in our laboratory for various animal species and humans. We tested the hypothesis that repeated exposure to pGz in mice would increase antioxidant enzymes, and determined its time course.
METHODS: Acclimated awake mice (n=48) where exposed to shear stress at f ƒ=480 cpm, Gz ± 3mt/sec 2 (pGz) 1 hr daily sessions of 1, 2, and 4 weeks of pGz. Myocardial tissue was harvested prior to pGz (BL) and 24 hrs after the last pGz treatment for proteins via Western Blot analyses: Glutathioneperoxidase-1(GPX1), Superoxide Dismutase -1 (Cu-Zn SOD), Superoxide Dismutase -2 (mitochondrial or Mn-SOD) and Catalase (Cat) , Protein content was normalized to GAPDH.
RESULTS:One to four weeks of pGz increased GPX1, Cat and SOD1 from BL levels, whereas SOD2 remained unchanged. 4 weeks of pGz increased GPX1, Cat and SOD1, by 110%, 80% and 240% of basal enzyme levels. (Data= mean ± SEM, Figure † p< 0.01 BL vs. 1,2,4 wks)
CONCLUSIONS: One hour daily pGz increases cardiac antioxidant enzymes and may serve as a method to augment endogenous antioxidant capacity, and decrease reperfusion injury.
- © 2012 by American Heart Association, Inc.