Chlorpyrifos Exposure Induces Parkinsonian Symptoms and Associated Bone Loss in Adult Swiss Albino Mice.

Prenatal and early life exposure of chlorpyrifos (CPF), a widely used pesticide, is known to cause neuronal deficits and
Parkinson’s disease (PD). However, data about the effect of its exposure at adult stages on PD-like symptoms and associated
bone loss is scanty. In the present study, we investigated the impact of CPF on the behavioral alterations seen in PD using adult
Swiss albino mice. PD is often associated with bone loss. Hence, skeletal changes were also evaluated using micro-computed
tomography and histology. MPTP was used as a positive control. Cell culture studies using MC3T3E-1, SHSY5Y, and primary
osteoclast cultures were done to understand the cellular mechanism for the behavioral and skeletal changes. Our results showed
that CPF treatment leads to PD-like symptoms due to the loss of dopaminergic neurons. Moreover, CPF has a deleterious effect
on the trabecular bone through both indirect changes in circulating factors and direct stimulation of multinucleate osteoclast cell
formation. The impact on the bone mass was even stronger than MPTP. In conclusion, this is the first report demonstrating that
CPF induces parkinsonian features in adult Swiss albino mice and it is accompanied by loss of trabecular bone.