Melatonin counteracts age-related progression of oxidative stress in young Down syndrome patients.

Document Type : Original Article

Authors

1 Department of Zoology, Faculty of Science, Mansoura University, Mansoura, Egypt.

2 Department of Zoology, Faculty of Science, Mansoura University, Mansoura, Egypt

3 Genetic Unit of Children Hospital, 1 Department of Pediatrics and Genetics, Faculty of Medicine, Mansoura University, Mansoura, Egypt.

Abstract

Melatonin (MLT) is a pineal gland hormone known for its potent antioxidant effect associated with neural protection. The presence of three copies of the SOD gene is considered to be the main cause of oxidative stress-dependent neural degeneration and dementia that Down syndrome (DS) patients may suffer from. In this study we aim to assess a possible protective effect of MLTagainst the age-related progression of oxidative stress-induced damage in lymphocytes of DS patients. Lymphocytes from infants with DS were treated with mitomycin C (an H2O2 promoter) in order to mimic the oxidative stress status of aged patients in presence and absence of MLT. The data indicated a significant effect of MLT in downregulating the levels of the oxidative radicalsH2O2 and NO compared to untreated DS patients’ lymphocytes. This downregulation was accompanied by a profound effect of MLT in reducing the number of oxidative stress-dependent damaged chromosomes, along with a reduction in cell apoptosis and DNA protection in the p53 dependent pathway. These observations suggest that early administration of exogenous MLT in young DS patients may help in gaining control over growth-related progression of mental retardation, or at least delaying the onset of DS-related pathological complications.

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