A Single Zidovudine (AZT) Administration Delays Hepatic Cell Proliferation by Altering Oxidative State in the Regenerating Rat Liver

The 3′-azido-3′-deoxythymidine or Zidovudine (AZT) was the first antiretroviral drug used in the treatment of HIV patients, which has good effectiveness but also hepatotoxic side effects that include cell cycle arrest and oxidative/nitrative mitochondrial damage. Whether such an oxidative damage may affect the proliferative-regenerative capacity of liver remains to be clearly specified at doses commonly used in the clinical practice. In this study, we described the oxidative-proliferative effect of AZT administered at a common clinical dose in rat liver submitted to 70% partial hepatectomy (PH). The results indicate that AZT significantly decreased DNA synthesis and the number of mitosis in liver subjected to PH in a synchronized way with the promotion of organelle-selective lipid peroxidation events (especially those observed in plasma membrane and cytosolic fractions) and with liver enzyme release to the bloodstream. Then at the dose used in clinical practice AZT decreased liver regeneration but stimulates oxidative events involved during the proliferation process in a way that each membrane system inside the cell preserves its integrity in order to maintain the cell proliferative process. Here, the induction of large amounts of free ammonia in the systemic circulation could become a factor capable of mediating the deleterious effects of AZT on PH-induced rat liver regeneration.