A selective peroxisome proliferator-activated receptor-γ agonist benefited propionic acid induced autism-like behavioral phenotypes in rats by attenuation of neuroinflammation and oxidative stress.

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder in children. It is diagnosed by two main behavioral phenotypes i.e. social-communication impairments and repetitive behavior. ASD is complex disorder with unsolved etiology due to multiple genes involvement, epigenetic mechanism and environmental factors. The clinical and preclinical studies have been indicating the association of propionic acid with autism spectrum disorder. Numerous studies suggest the potential therapeutic effects of peroxisome proliferator-activated receptor-gamma (PPAR-γ) in different brain disorders. This research evaluates the utility of selective agonist of PPAR-γ, pioglitazone in postnatal propionic acid induced ASD related symptomatology in male Wistar rats. PPA (250 mg/kg, p.o.) was administered to male offspring for three consecutive days from postnatal 21st day to 23rd day. PPA induced social impairment, repetitive behavior, hyperlocomotion, anxiety and low exploratory activity in rats. Also, postnatal propionic acid-treated rats showed higher levels of oxidative stress (increased in thiobarbituric acid reactive species and decreased in reduced glutathione) as well as inflammation (increased in interleukin-6, tumor necrosis factor-alpha and decreased in interleukin-10) in the cerebellum, brainstem and prefrontal cortex. The rats were treated daily with pioglitazone (10 mg/kg and 20 mg/kg, p.o.) from postnatal 24th day to end of the study. Treatment with pioglitazone, significantly attenuated the postnatal propionic acid-induced social impairment, repetitive behavior, hyperactivity, anxiety and low exploratory activity. Furthermore, pioglitazone also reduced the postnatal propionic acid-induced oxidative stress and neuroinflammation in aforementioned brain regions. Hence, pioglitazone improved the propionic acid-induced neurobehavioral and biochemical impairments in rats.