N-acetylcysteine effectively mitigates cadmium-induced oxidative damage and cell death in Leydig cells in vitro

Cadmium (Cd) is known to cause severe damage to various organs including lung, liver, kidney, brain and reproductive system. Several studies have reported the induction of oxidative stress pathways following Cd exposure.

Since oxidative stress is also deemed responsible for inducing male infertility, a growing worldwide concern, we tried to understand whether the antioxidant N-acetylcysteine (NAC) can be a potential therapeutic agent to counter Cd toxicity using primary Leydig cells.

This study highlights the initial cellular alterations which culminate in cell death induction. Primary Leydig cells were isolated from 28-day-old male Wistar rats, exposed to various concentrations of Cd in vitro and biochemical and cell death parameters were evaluated to understand the effect of Cd. NAC pre-treatment was done to understand its protective efficacy.

Following Cd exposure to Leydig cells in vitro, we found simultaneous intracellular calcium (Ca(2+)) increase and reduction in mitochondrial membrane polarization at 30 min, followed by significant induction of reactive oxygen species and MAPK-extracellular-regulated kinases with concurrent glutathione depletion at 1 h, and significant cell death (both necrotic and apoptotic) at 6 and 18 h, respectively. Pre-treatment with NAC abrogated all these toxic manifestations and showed significantly reduced cell death. NAC also rescued the expression of 3-βHSD, a major steroidogenic protein.

Taken together, these data illustrated that NAC can be used as a potential protective agent against Cd-induced testicular toxicity, especially with regards to oxidative stress-induced Leydig cell toxicity.