Protecting Effects of N-acetyl Cysteine Supplementation Against Lead and Cadmium-Induced Brain Toxicity in Rat Models.

We aimed to investigate mitigating effects of N-acetylcysteine (NAC) on the oxidative stress, apoptosis and Parkinson's disease (PD)-related genes in the brain tissue of male rats exposed to continuous doses of cadmium and lead. Rats were randomly divided into five groups, including G1 (control), G2 (continuous dose of Cd), G3 (continuous dose of Pb), G4 (continuous dose of Cd + NAC), and G5 (continuous dose of Pb + NAC). Biomarkers of oxidative stress, malondialdehyde (MDA), and total antioxidant capacity (TAC) were measured. Expression of PD- and apoptosis-related genes was considered using RT-PCR. Chronic exposure to these heavy metals was associated with accumulation of Pb and Cd in the brain and blood and caused severe morphological changes in the brain, as well as decreased body and brain weights. Continuous exposure to Cd and Pb significantly decreased TAC content and SOD expression but increased MDA level in the brain tissues (P < 0.001). A significant increase was observed in expression of PD-related genes, Parkin, Pink1, LRRK2, SNCA, and Caspase-3 in the brain tissues following exposure to Cd and Pb. Pb exhibited stronger toxicity on the brain tissue compared to Cd. NAC supplementation not only improved morphological changes, but also compensated antioxidant capacity and expression of apoptosis- and PD-related genes in the brain tissues when compared to rats exposed to Pb and Cd alone. Chronic exposure to Pb and Cd is strongly associated with accumulation of these heavy metals in the brain, morphological changes, antioxidants depletion, oxidative stress, and brain cells apoptosis. Changes in expression of PD-related genes indicate the higher risk of PD among individuals who are chronically exposed to these heavy metals. NAC can protect brain tissue against Pb and Cd toxicity by elevating antioxidants capacity, mitigating oxidative stress, apoptosis, and down-regulating of PD-related genes.

Effects of zinc deficiency on impaired spermatogenesis and male infertility: the role of oxidative stress, inflammation and apoptosis.

Zinc (Zn) is necessary for the normal function of the male reproductive system and spermatozoa. Although influences of zinc deficiency on impaired spermatogenesis and male infertility have been widely considered, the molecular and cellular mechanisms of these abnormalities are not well understood. General abnormalities, including hypogonadism, Leydig cells damage, deficiency of sex hormone production and impaired spermatogenesis, as well as inflammation, antioxidant depletion, sperm death and male infertility can be observed during zinc deficiency. However, it is not obvious which pathways are relevant to the pathogenesis of zinc deficiency. Oxidative stress (OS) induced by reactive oxygen species is likely as the main mechanism of zinc deficiency which is associated with sperm DNA fragmentation, decrease in sperm membrane integrity, apoptosis, depletion of antioxidants, and consequently poor sperm quality and male infertility. Therefore, identification of these pathways will give valuable information regarding the mechanisms of zinc deficiency on the male reproductive system and the potential way for developing a better clinical approach. In this review, we aim to discuss the proposed cellular and molecular mechanisms of zinc deficiency on the male reproductive system, the importance of OS and mechanisms by which zinc deficiency induces OS and depletion of other antioxidants.

Role of oxidative stress and antioxidant therapy in acute and chronic phases of sulfur mustard injuries: a review.

Sulfur mustard (SM) is a chemical compound that preferentially targets ocular, cutaneous and pulmonary tissues. Although pathologic effect of SM has been extensively considered, molecular and cellular mechanism of its toxicity, especially at the chronic phase of injury is not well-understood. Excessive production of reactive oxygen species (ROS) and oxidative stress (OS) appears to be involved in SM-induced injuries. SM may trigger several molecular and cellular pathways linked to OS and inflammation that can subsequently result in cell death and apoptosis. At the acute phase of injury, SM can enhance ROS production and OS by reducing the activity of antioxidants, depletion of intercellular glutathione (GSH), decreasing the productivity of GSH-dependent antioxidants, mitochondrial deficiency, accumulation of leukocytes and pro-inflammatory cytokines. Overexpression of ROS producing enzymes and down-regulation of antioxidant enzymes are probably the major events by which SM leads to OS at the chronic phase of injury. Therefore, antioxidant therapy with potent antioxidants such as N-acetylcysteine and curcumin may be helpful to mitigate SM-induced OS damages. This review aims to discuss the proposed cellular and molecular mechanisms of acute and delayed SM toxicity, the importance of OS and mechanisms by which SM increases OS either at the acute or chronic phases of injuries along with research on antioxidant therapy as a suitable antidote.