Neonatal Bisphenol A Exposure Alters Thyroid-Axis and Prooxidant-Antioxidant Balance in Brain of Rat (Published)
The aim of this study was to investigate the possible effects of neonatal bisphenol A (BPA) exposure on the neuroendocrine system (thyroid-brain axis). 20 or 40 µg/kg of BPA was orally administered to neonatal male albino rats (Rattus norvigicus) from postnatal days (PNDs) 15 to 30. Both administrations gave rise to a lower serum thyroxine (T4) and triiodothyronine (T3) levels, and higher thyrotropin (TSH) level than control group at PND 30. Also, a marked reduction in serum of neonatal growth hormone (GH) was observed in both treated groups. In neonatal cerebellum and cerebrum, the elevations of oxidative markers [lipid peroxidation (LPO), nitric oxide (NO), and hydrogen peroxide (H2O2)] due to both administrations were observed at PND 30, along with decreased activities of antioxidants markers [total ascorbic acid (TAA), total thiol (t-SH), glutathione (GSH), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST), and catalase (CAT)] with respect to control group. Thus, hypothyroidism in BPA might disturb the neonatal thyroid-brain axis via production of free radicals, and this, might destruct the plasma membrane and cellular components delaying cerebrum and cerebellum development.
Keywords: Antioxidants, Bisphenol A, Cerebellum, Cerebrum, Prooxidants., Thyroid hormones
Antioxidant System Responses of the Coriander (Coriandrum Sativum) Plant To Chromium Toxicity (Published)
The aim of this study was to compare the effect of different doses of chromium on antioxidant system of the coriander. A total of the coriander seeds were divided among 3 groups. The cultivation of plants was occurred and treated with different concentrations of sulfate (0.4, 0.8 &1.6 mM magnesium sulfate) for 6 weeks until completely growth and ensure for healthy. Each treatment group was divided into three subgroups to handle treatment concentration of 0 µM, 50 µM and 100 µM chromium. Antioxidants (peroxidase, GSH, Ascorbic acid, ASPX, SOD and Catalase( and lipid peroxidation were recorded. All level of Cr treatments lead to numerically decreased in peroxidase, GSH, Ascorbic acid, ASPX, SOD of the coriander than the control. Furthermore, 100 µM of Cr treatments lead to numerically decreased in catalase of the coriander than the control. However, all level of Cr treatments led to numerically increase in lipid peroxidation of the coriander plant than the control. These adverse effects of chromium were encountered with increasing sulfur supply in the irrigation solution. Sulfur decreases the uptake of chromium in coriander plant. Sulfur also alleviates most harmful effect of chromium by enhancement of the antioxidative system (especially GSH content) in the coriander plant. The effect of sulfur was more effective at 50 µM Cr than 100 µM Cr. The two concentration of sulfur were both effective.
Keywords: Antioxidants, Chromium toxicity, coriander, sulfur
LACTATING PTU EXPOSURE: II- ALTERS THYROID-AXIS AND PROOXIDANT-ANTIOXIDANT BALANCE IN NEONATAL CEREBELLUM (Published)
The aim of the present study was to evaluate the effect of lactating 6-propyl-2-thiouracil (PTU) on the interactions between the thyroid-axis and prooxidant/antioxidant markers in neonates. PTU was administered to female rats in drinking water (0.1% w/v) from birth to lactation day (LD) 30. The administration gave rise to a highly significant decrease in serum thyroxine (T4) and triiodothyronine (T3) levels and increase in serum thyrotropin (TSH) level in both dams and their offspring at LDs 20 and 30 relative to control group. Also, in PTU group, a marked depression was observed in serum of neonatal growth hormone (GH). In this hypothyroid state, obvious elevation of oxidative markers (protein carbonyls, lipid peroxidation, NO and H2O2) was observed at postnatal days (PNDs) 20 and 30, along with decreased activities of antioxidants markers (total thiol, glutathione, glutathione peroxidase, superoxide dismutase and catalase) in neonatal cerebellum with respect to control group. Also, the administration caused some histopathological changes in neonatal cerebellar cortex, such as oedema, vacuoles, reduction of the Purkinje cells, and cellular fragmentations at PND 30. Thus, hypothyroidism in lactating PTU impairs the neonatal neuroendocrine system via production of free radicals, and this, may cause damage of proteins and lipids at the plasma membrane and cellular components delaying cerebellum development
Keywords: 6-propyl-2-thiouracil, Antioxidants, Cerebellum, Prooxidant, Rat newborns, Thyroid