The Protective Effects of Melatonin Against Oxidative Stress and Inflammation Induced by Acute Cadmium Exposure in Mice Testis

Abstract

Cadmium (Cd) is widely used in daily life and was recently recognized as a possible source of human toxicity due to its ability to accumulate in organs. Previous studies have shown that Cd exposure may cause testicular toxicity through oxidative stress and an inflammatory effect. Melatonin has been demonstrated to be an effective anti-oxidant and has an anti-inflammatory effect. The aim of the present study was to investigate the toxicological effects of Cd on reproduction in male mice and the potential protective action of melatonin against these adverse effects. Adult male mice were injected intraperitoneally with Cd at a dose of 2 mg/kg body weight per day for seven consecutive days with or without melatonin pretreatment. Sex organ weight, sperm parameters including sperm quality, apoptosis, acrosome integrity, mitochondrial membrane potential, testicular morphology, serum sex hormone, inflammatory status, and oxidative stress were evaluated. The results showed that significant adverse effects were observed in the male reproductive system after Cd exposure, including alterations in sperm parameters, increased DNA damage, and sex hormone disturbance. Acute Cd exposure also significantly increased malondialdehyde (MDA) contents, decreased glutathione (GSH) and superoxide dismutase (SOD) activities, and upregulated levels of the pro-inflammatory cytokines, tumor necrosis factor-alpha (TNF-α), and interleukin-1beta (IL-1β), in the testis. In contrast, melatonin pretreatment significantly alleviated these toxic effects, and its mechanism may involve inhibiting MDA level, restoring GSH and SOD activities, and reducing the upregulation of TNF-α and IL-1β. Our data suggest that oxidative stress and inflammation are involved in Cd-induced toxicity in the male reproductive system and that co-administration of melatonin exerts a protective effect against Cd-induced male reproductive toxicity.

Sulforaphane Prevents Testicular Damage in Kunming Mice Exposed to Cadmium via Activation of Nrf2/ARE Signaling Pathways

“…SOD is an important antioxidant defense system in cells. The present study found that testicular SOD activity was significantly reduced in the cadmium-treated group, presumably due to oxidative stress, and the findings were consistent with previous studies [37,38]. By contrast, sulforaphane increased the activity of SOD in mouse testis.…”

Melatonin Scavenger Properties against Oxidative and Nitrosative Stress: Impact on Gamete Handling and In Vitro Embryo Production in Humans and Other Mammals

“…Additionally, the melatonin supplementation of semen extenders increases sperm motility and viability, and decreases ROS levels and lipid peroxidation [80], which improves the sperm quality after the freezing-thawing processes [133]. This antioxidant can protect from testicular injury induced by oxidative stress after cadmium (Cd) exposure [96]. Melatonin helps to protect sperm from ROS induced by cell sorting, a widely used technique for in vitro fertilization or artificial insemination [133].…”

Dietary Sources and Bioactivities of Melatonin

“…As the biological roles of melatonin were widely studied, the recognized therapeutical effects and the health benefits of melatonin could cover a broad range. Melatonin could regulate human physiological rhythm, alleviate related disorders like jet lag [2] and insomnia [3], scavenge free radical species [4], enhance the immune system [5], show anti-aging [6] and anti-inflammatory effects [7] and perform anticancer activities [8]. Moreover, melatonin could also exhibit neuroprotective effects [9], facilitate the control of chronic diseases, such as cardiovascular diseases [10], diabetes [11] and obesity [12].…”