Recent clinical observations suggest that certain gut and dietary factors may transiently worsen symptoms in
autism. Propionic acid (PA) is a short chain fatty acid and an important intermediate of cellular metabolism. Although PA has
several beneficial biological effects, its accumulation is neurotoxic.
Two groups of young Western albino male rats weighing about 45 to 60 grams (approximately 21 days old) were used
in the present study. The first group consisted of oral buffered PA-treated rats that were given a neurotoxic dose of 250 mg/
kg body weight/day for three days, n = eight; the second group of rats were given only phosphate buffered saline and used as a
control. Biochemical parameters representing oxidative stress, energy metabolism, neuroinflammation, neurotransmission, and
apoptosis were investigated in brain homogenates of both groups.
Biochemical analyses of brain homogenates from PA-treated rats showed an increase in oxidative stress markers (for
example, lipid peroxidation), coupled with a decrease in glutathione (GSH) and glutathione peroxidase (GPX) and catalase
activities. Impaired energy metabolism was ascertained through the decrease of lactate dehydrogenase and activation of creatine
kinase (CK). Elevated IL-6, TNFalpha, IFNgamma and heat shock protein 70 (HSP70) confirmed the neuroinflammatory effect
of PA. Moreover, elevation of caspase3 and DNA fragmentation proved the pro-apoptotic and neurotoxic effect of PA to rat pups
By comparing the results obtained with those from animal models of autism or with clinical data on the biochemical
profile of autistic patients, this study showed that the neurotoxicity of PA as an environmental factor could play a central role in
the etiology of autistic biochemical features.
Afaf El-Ansary, Professor of Biochemistry, received her PhD from Ain Shams University, Egypt in 1990. She has post-doctoral experience in the field of metabolic integration in parasitic diseases, Medicinal Chemistry Department, Egypt. After ten years, she joined Biochemistry Department, Science College, King Saud University, Saudi Arabia. She has a sound expertise in the field of biomarkers of neurological disorders with special reference to Autism Spectrum Disorders. She is a member on board of Voice of Mentally Retarded Association, Egypt. Acts as a reviewer for many international Journals and has more than 70 highly cited publications in her research interest
Peer Reviewed Journals
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals