Downregulated Recycling Process but Not De Novo Synthesis of Glutathione Limits Antioxidant Capacity of Erythrocytes in Hypoxia

Figure 5

Hypoxia promotes oxidative phosphorylation of Band 3 in RBCs exposed to oxidative stress. (a) The expressions of G3PD, Band 3, and phosphotyrosine in normoxic and hypoxic RBCs were evaluated by Western blot. (b) Fluorescent micrographs for normoxic and hypoxic RBCs after immunostaining with monoclonal antibodies to Band 3. The arrows indicate protein clusters after HX/XO exposure. . (c) Densitometric analyses of immunoblots of Band 3. (d) Densitometric analyses of immunoblots of phosphotyrosine protein. (e) Densitometric analyses of immunoblots of GAPDH. Glutathione-related parameters, including GSH (f), TFG (g), and GSH/GSSG ratio (h) in normoxic and hypoxic RBCs with pretreatment of DHEA (inhibitor of HMP key enzyme G6PD), KA (inhibitor of EMP key enzyme GAPDH), or CO (stabilizing Hb conformation). Data represent the of at least three independent experiments. and for normoxic or hypoxic RBCs vs. corresponding RBCs with HX/XO exposure. ^# for normoxic RBCs vs. corresponding hypoxic RBCs.

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