Behavioral and neurochemical effects in mice after one-generation exposure to low doses of manganese: Focus on offspring development

The risk of exposure to toxic metals is a known concern to human populations. The overexposure to Mn can lead to a pathological condition, with symptoms similar to Parkinson's disease. Although toxicity of Mn has been reported, studies in neonates are scarce but necessary, as Mn can cross biological barriers. The present study evaluated if chronic perinatal exposure to Mn at low doses lead to neurotoxic effects in mice, after direct and indirect exposure. Couples of mice were exposed to Mn (0.013, 0.13, and 1.3 mg kg−1.day−1) for 60 days prior to mating, as well as during gestation and lactation. The offspring was distributed into two groups: animals that were not exposed after weaning - parental exposure only (PE); and animals subject to additional 60-day exposure through gavages after weaning - parental and direct exposure (PDE). Neurological effects were evaluated by Mn quantification, behavior tests and biochemical markers in the brain. PDE animals had alterations in short/long-term memory and increased anxiety-like behavior. Exposure to Mn triggered a decrease of glutathione-s-transferase and increase of cholinesterase activity in different regions of the brain. These findings highlight the risk of exposure to low doses of Mn over a generation and at early stages of development. [Display omitted] •The effects of Mn were studied in parental and parental+direct-exposed mice.•Chronic exposure to Mn can change Mn distribution in the brain.•GST and AChE activities are affected by Mn in different regions of brain.•Mn effects in the brain are related to anxiety-like behavior and memory alterations.