Cytoarchitecture changes of the rat thyroid gland following Furan administration implemented Fas-apoptotic pathway with potential abrogating role of selenium

Abstract

Background: Furan, a cytotoxic chemical produced during thermal processing of foods, is an endocrine disruptor that induces injury of most endocrine glands. The aim of this study is To evaluate the effects of furan exposure on cytoarchitecture of the rat thyroid gland and to assess the potential protective role of selenium (Se). Methods: Twenty-four male Sprague Dawley rats were allocated into four groups and gavaged daily for 4 weeks. I (Control group) received corn oil, II (Se group) received selenium (1μg/100g bw/day), III (Furan group) received furan (40 mg/kg bw/day), and IV (Furan/Se group) received furan and Se simultaneously. Serology was performed and Paraffin sections of thyroid gland were processed for staining by H&E and Periodic Acid Schiff (PAS). Also, immunohistochemical study was carried out for detection of Fas protein and the proliferating cell nuclear antigen (PCNA). Moreover, morphometric analysis was performed. Results: Furan group exhibited discernible histopathological changes in the thyroid gland; outcomes associated with depleted thyrocolloid and decreased its mean area % and extensive immunoexpression of Fas and PCNA with increased their mean area %. In addition, furan group displayed increased serum malondialdehyde (MDA), interleukin-1 β (IL-1β), tumour necrosis factor alpha (TNF-α), and thyroid stimulating hormone (TSH) but serum reduced glutathione (GSH), glutathione peroxidase-1 (GPX-1) activity, and serum total T3, T4 were decreased. Co-supplementation of Se with furan partially ameliorated the histological, immunohistochemical and biochemical changes. Conclusion: Furan induced deleterious effects on rat thyroid gland that mediated mostly via induction of oxidative, inflammatory and Fas apoptotic pathways; resultants that were abrogated by Se.