Impact of undernutrition on apoptotic pathways and thymocyte development in rats: insights into caspase activation and mitochondrial dysfunction

Abstract Undernutrition significantly compromises immune function, particularly in vulnerable populations. This study explored the effects of undernutrition on apoptotic pathways and thymocyte development in rats, shedding light on potential mechanisms underlying immunosuppression. Undernutrition was induced by competitive suckling, leading to weight deficits of 40 % or more. Thymic involvement was assessed by thymus weight, total thymocyte number and flow cytometry to evaluate mitochondrial function, caspase activation and alterations in subpopulations, providing insights into the mechanisms underlying immune suppression induced by undernutrition. Undernourished rats exhibited a marked reduction in thymus weight and thymocyte cellularity, accompanied by significant alterations in thymocyte subpopulations and diminished mitochondrial potential. Analysis of caspase activation revealed a significant role for caspase 9 in early apoptosis, suggesting a link between mitochondrial dysfunction and thymocyte apoptosis induced by undernutrition. These alterations in thymic structure and apoptotic pathways are consistent with previous studies, underscoring the vulnerability of the thymus to undernutrition. The alterations observed in thymocyte subpopulations and caspase activation patterns provide insight into the intricate relationships among undernutrition, thymic function and immune suppression. This study contributes to the understanding of how undernutrition during lactation affects thymic function and apoptotic pathways. These findings highlight the critical need for additional research to elucidate the underlying mechanisms and identify potential therapeutic interventions to alleviate the detrimental effects of undernutrition on thymic development and immune function.