Melatonin attenuates cardiac injury caused by chromium-mediated oxidative stress in male Wistar rats: involvement of antioxidative mechanisms

Cardiovascular disease (CVD) is a global health concern due to its high mortality. Heavy metals are the potential risk factor for CVD. Among other heavy metals, chromium (Cr) is considered a serious threat to human health due to its high oxidative capacity. In the current study, male Wistar rats were treated with Cr to induce cardiac tissue injuries, meanwhile, melatonin was given to test whether this treatment can protect against Cr-induced cardiac damage. The results showed that Cr markedly altered the heart weight, biomarkers of oxidative stress, activities of antioxidant and pro-oxidant enzymes, as well as tissue morphology. On contrary, melatonin treatment significantly suppressed all these alterations via its antioxidant activity. In addition, melatonin also significantly reduced tissue Cr concentration probably through its metal-chelating activity. The current study has demonstrated that melatonin is a promising antioxidant to protect the heart from Cr-induced oxidative damage, confirming that melatonin can be a future therapeutic agent for Cr-mediated toxicity in the heart or other organs.