Discipline: Biological Sciences
Subcategory: Cell and Molecular Biology
Brandon W. Hughes - Claflin University
Autism Spectrum Disorder (ASD) is a set of complex developmental disorders whose etiology is debatable. Although the symptoms may vary from person to person, they include impairment or loss of speech, lack of empathy, and social
interaction deficiency. The cases of ASD have continued to increase drastically each year, with the CDC estimating 1:68 children diagnosed, along with 4 to 5 times more prevalence in males. It is believed that the ASD is caused by a combination of genetic and environmental factors, but recent studies suggest that exposure to environmental chemicals may play a critical role in its pathogenesis. Although there are no biomarkers for the disease, low levels of oxytocin and arginine vasopressin have been reported. These neuropeptides play a critical role in neurodevelopment of male brain. Here we assessed the potential neurotoxic effects of everyday female fragrances in order to determine if there are morphological and immunological changes to neurons, which may suggest that they contribute to the development of ASD during gestation.
In order to determine whether chemicals in fragrances have a neurotoxic effect on fetal brain development, two cell lines derived from male and female neuroblastoma were used as an experimental model. After exposure of the cells to the particular fragrances, immunostaining was performed with oxytocin and arginine vasopressin receptor antibodies to determine the up or down regulations of these receptors. Immunofluorescence showed that cells exposed to fragrances significantly reduced the percentage of OXY and AVP receptor positive neurons in fetal male brain cell lines but not the cell lines from female. Separately, differences in cell structure between the cells treated with fragrances and the untreated control cells were detected using hematoxylin and eosin (H&E) staining. There were significant changes observed; including axon elongation and thinning, syncytia formation, and central chromatolysis.
These results suggest a correlation between low levels of OXY/AVP and fragrance exposure, with a potential cause for ASD. Future research will include six other neuroblastoma cell lines and a statistical analysis of the characteristics observed thorough H&E staining and immunohistochemistry, which will quantitatively help determine the effects of the fragrances on the migration, differentiation, and organization of fetal brain neurons. This may shed light on the pathogenesis of autism and male gender bias.
Funder Acknowledgement(s): Awarding Agency: U.S. Department of Education; Project Name: HBCU Master's Degree Program; Award Number: P382G090010
Faculty Advisor: Omar Bagasra, email@example.com