Maternal Treadmill Exercise and Zinc Supplementation Alleviate Prenatal Stress–Induced Cognitive Deficits and Restore Neurological Biomarkers in Offspring: A Study on Male Rats Aged 30 and 90 Days

The detrimental effects of prenatal stress (PS) on offspring's neurological and behavioral outcomes are well documented. However, strategies to mitigate these effects are underexplored. This study examines whether prenatal zinc supplementation and treadmill exercise can modulate PS-induced cognitive impairments and neurobiological markers in young and adult male rat offspring, leveraging the established neuroprotective potential of both physical activity and zinc. Pregnant rats were divided into five groups: control, stress, stress + exercise, stress + zinc, and stress + exercise + zinc, with all rats except the control group subjected to restraint stress (gestational days 15-19). Pregnant rats in the exercise groups underwent forced exercise, whereas those in the zinc groups received oral zinc sulfate throughout the pregnancy. At postnatal days 30 and 90, the cognitive function of male offspring was evaluated using the Morris water maze (MWM) test, and the hippocampal gene expression levels of caspase-3, brain-derived neurotrophic factor (BDNF), and glial fibrillary acidic protein (GFAP) were measured using reverse transcription-polymerase chain reaction (RT-PCR). PS impaired cognitive functions, increased caspase-3 expression, and decreased BDNF and GFAP expression levels in adult rats. Prenatal exercise was found to mitigate PS-induced cognitive deficits primarily through enhancing GFAP expression, whereas prenatal zinc improved PS-induced cognitive impairments mainly through reduced caspase-3 and increased BDNF expression. The combined effect of exercise and zinc was not additive on cognitive functions and biomarkers. Physical activity may alleviate PS-induced cognitive deficits by modulating astrocytic factors, whereas zinc may exert its effects by inhibiting apoptosis via a BDNF-dependent pathway. Further targeted research is necessary to confirm these relationships.