Loss of GSH, Oxidative Stress, and Decrease of Intracellular pH as Sequential Steps in Viral Infection

Abstract

Madin-Darby canine kidney cells infected with Sendai virus rapidly lose GSH without increase in the oxidized products. The reduced tripeptide was quantitatively recovered in the culture medium of the cells. Since the GSH loss in infected cells was not blocked by methionine, a known inhibitor of hepatocyte GSH transport, a nonspecific leakage through the plasma membrane is proposed. UV-irradiated Sendai virus gave the same results, confirming that the major loss of GSH was due to membrane perturbation upon virus fusion. Consequent to the loss of the tripeptide, an intracellular pH decrease occurred, which was due to a reversible impairment of the Na ؉ /H ؉ antiporter, the main system responsible for maintaining unaltered pH i in those cells. At the end of the infection period, a rise in both pH i value and GSH content was observed, with a complete recovery in the activity of the antiporter. However, a secondary set up of oxidative stress was observed after 24 h from infection, which is the time necessary for virus budding from cells. In this case, the GSH decrease was partly due to preferential incorporation of the cysteine residue in the viral proteins and partly engaged in mixed disulfides with intracellular proteins. In conclusion, under our conditions of viral infection, oxidative stress is imposed by GSH depletion, occurring in two steps and following direct virus challenge of the cell membrane without the intervention of reactive oxygen species. These results provide a rationale for the reported, and often contradictory, mutual effects of GSH and viral infection.

Multidrug Resistance-associated Protein-1 (MRP-1)-dependent Glutathione Disulfide (GSSG) Efflux as a Critical Survival Factor for Oxidant-enriched Tumorigenic Endothelial Cells

“…1E). Low cellular GSH is a hallmark of high oxidant burden (13,46,47). Consistently, EOMA cells showed low GSH ( Fig.…”

Resveratrol Protects Sepsis-Induced Oxidative DNA Damage in Liver and Kidney of Rats

“…In the standard comet assay, there were no statistically significant differences in terms of DNA tail length (TL), DNA tail intensity (TI), and DNA tail moment (TM) in the liver and kidney cells between the sham and the RV-treated groups. All DNA damage parameters in the sepsis group were significantly higher than in the sham group (p<0.05) and RV treatment significantly reduced DNA damage induced by sepsis in these tissue cells (24 the kidney, respectively) (p<0.05). In the Fpg-modified comet assay, there were no statistically significant differences in all DNA damage parameters of the liver and kidney cells between the sham and the RV-treated groups.…”

“…The antioxidant defense system is impaired in sepsis (15). The reduction of GSH is supposed to reflect the intracellular oxidation impairing cellular functions and the strongest alteration in the antioxidant defense (23,24). The decreases in GSH and increases in MDA levels were determined in the hepatic and renal tissues of septic rats (25).…”

Activation of c-Jun-N-terminal kinase is required for apoptosis triggered by glutathione disulfide in neuroblastoma cells

“…Cell suspension was washed three times with PBS in order to completely eliminate exogenous GSSG, resuspended, and lysed by repeated cycles of freezing and thawing under liquid nitrogen. Lysates were then divided into two aliquots: one utilized for GSH/GSSG assay, while the other was used to determine mixed disulfides by treating with 300 mM NaBH 4 at 40-C for 30 min prior to derivatization, as described previously [13]. Data are expressed as nanomoles of GSH or GSSG per milligram protein.…”