Effects of rhodiola crenulata on mice hearts under severe sleep apnea

Abstract

Background: The goal of this study is to determine if Rhodiola Crenulata (RC) has protective effects on mice hearts with severe sleep apnea model. Methods: Sixty-four C57BL/6 J mice 5-6 months old were distributed into 4 groups i.e. Control group (21 % O2, 24 h per day, 8 weeks, n = 16); Hypoxia group (Hypoxia: 7 % O2 60 s, 20 % O2 alternating 60 s, 8 h per day, 8 weeks, n = 16); Hypoxia + 90RC and Hypoxia + 270RC group (Hypoxia for 1st 4 weeks and hypoxia pretreated 90 mg/Kg and 270 mg/Kg Rhodiola Crenulata by oral gavage per day for 2nd 4 weeks, each n = 16). Excised hearts from 4 groups of mice were analyzed for heart weight index changes using H&E staining, TUNEL-positive assays and Western Blotting protein. Results: Cardiac widely dispersed TUNEL-positive apoptotic cells in mice hearts were less in Hypoxia + RC90 and Hypoxia + RC270 than those in Hypoxia. Compared with Hypoxia, the protein levels of Fas ligand, Fas death receptors, Fas-Associated Death Domain (FADD), activated caspase 8, and activated caspase 3 (Fas dependent apoptotic pathways) were decreased in Hypoxia + RC90, Hypoxia + RC270. The protein levels of Bad, Bax, t-Bid, activated caspase 9, activated caspase 3 (mitochondria dependent apoptotic pathway) were less in Hypoxia + RC90, Hypoxia + RC270 than those in hypoxia. The protein levels of Bcl2, Bcl-xL, p-Bad (Bcl2-realted anti-apoptotic pathway) and VEGF, p-PI3k, p-AKT (VEGF-related pro-survival pathway) were higher in Hypoxia + RC90, Hypoxia + RC270 than those in hypoxia. Conclusions: Our findings suggest that Rhodiola Crenulata have protective effects on chronic intermittent hypoxia-induced cardiac widely dispersed apoptosis via Fas-dependent and mitochondria-dependent apoptotic and VEGF-related pro-survival pathway.