Prevalence and determinants of obesity among school going adolescents: A systematic review

Adolescence is considered as critical period for the development of obesity. The frequency of childhood obesity has increased over the last 3 decades, and it has emerged as a public health concern in multiple places around the world. A number of factors interact in a complex way to cause obesity, which is still not fully understood. Therefore, the purpose of this review was to identify and assess the scientific literature on the prevalence of obesity, and behavioural, contextual and biological factors associated with obesity in adolescents. The search was carried out using PubMed, Web of Science, Embase and Scopus considering articles published from the establishment of the databanks until December, 2022. Data on the prevalence of overweight and obesity among children and adolescents, and articles on the determinants and factors affecting obesity were reviewed. The results obtained and the association observed among the factors studied will be helpful to support the planning, implementation and evaluation of preventive activities and interventions

Potential biological role of poly (ADP-ribose) polymerase (PARP) in male gametes

Maintaining the integrity of sperm DNA is vital to reproduction and male fertility. Sperm contain a number of molecules and pathways for the repair of base excision, base mismatches and DNA strand breaks. The presence of Poly (ADP-ribose) polymerase (PARP), a DNA repair enzyme, and its homologues has recently been shown in male germ cells, specifically during stage VII of spermatogenesis. High PARP expression has been reported in mature spermatozoa and in proven fertile men. Whenever there are strand breaks in sperm DNA due to oxidative stress, chromatin remodeling or cell death, PARP is activated. However, the cleavage of PARP by caspase-3 inactivates it and inhibits PARP's DNA-repairing abilities. Therefore, cleaved PARP (cPARP) may be considered a marker of apoptosis. The presence of higher levels of cPARP in sperm of infertile men adds a new proof for the correlation between apoptosis and male infertility. This review describes the possible biological significance of PARP in mammalian cells with the focus on male reproduction. The review elaborates on the role played by PARP during spermatogenesis, sperm maturation in ejaculated spermatozoa and the potential role of PARP as new marker of sperm damage. PARP could provide new strategies to preserve fertility in cancer patients subjected to genotoxic stresses and may be a key to better male reproductive health