Low-Dose Exposure Led to Impaired Communication, Reduced Sociability, and Repetitive Behaviors
Canadian researchers have discovered that prenatal low-dose methylmercury (MeHg) exposure triggers autism-like behaviors in a rodent model. By studying adult mice that had been prenatally exposed to non-apoptotic (low dose) MeHg, the team noticed the mice exhibited key autism characteristics, including impaired communication, reduced sociability, and increasingly restrictive repetitive behavior. The authors performed early postnatal ultrasonic vocalization analyses on participant mice to test the rodent’s communication skills. Mouse pups emit calls during their first two weeks when separated from their mother and littermates. The researchers discovered that mice prenatally exposed to low-dose MeHg vocalized significantly less than the control group mice during this period. To examine repetitive behaviors, the team used the Marble Burying test and discovered that mice prenatally treated with low-dose MeHg buried significantly more marbles than control mice. The authors used the adult social interaction test to examine social skills. Once again, the low-dose MeHg mice scored poorly on this test. The team also found that mice prenatally treated with low-dose MeHg showed poor reversal memory, similar to genetic ASD mouse models. Interestingly, the study discovered that metformin, an FDA-approved drug, can reverse some MeHg-induced impairment in the subject mice. The authors suggest that the drug has the potential to be a future therapeutic strategy for autism.
