EXPLORATION OF GOITROGENIC/ANTITHYROIDAL POTENTIALITY OF BAMBOO-SHOOTS IN RELATION TO THIOUREA

Objective: Natural goitrogens present in plant foods or antithyroidal drugs both alter the morphology and normal functional status of the thyroid gland interfering the synthesis and secretion of thyroid hormones. In this study, the goitrogenic potential of bamboo shoots (BS) containing natural goitrogens has been compared against a potent synthetic antithyroidal drug thiourea. Methods: BS was fed to 6 rats by 1/3 rd replacement of 180grams (g) of their food i.e.60g of BS containing 35g of goitrogens of cyanogenic origin such that each rat ideally consumed 6 mg/100g of body weight per day and thiourea at a near equal dose of 6 mg/100g of body weight per day was force fed to another 6 rats for a period of 45 d. Changes in food consumption pattern, serum toxicity marker SGOT and SGPT, morphological changes like thyroid gland weight and histology and functional aspects like TPO activity, Na+-K+ATPase activity, urinary iodine excretion and serum T3,T4 and TSH levels induced by this natural and synthetic agent respectively were investigated. Results analyzed by ANOVA followed by post hoc tests. Results: Food consumption pattern was similar in all groups while serum toxicity markers SGOT, SGPT showed a non-significant increase in experimental groups. Increase in body and thyroid gland weight as compared to control was seen on treatment with both antithyroidal agents, a greater percentage of increase was seen in thiourea treated group. TPO activity, Na+-K+ATPase activity, serum T3 and T4levels were decreased significantly in both treated groups as compared to normal, with maximum inhibition in the thiourea treated group. Histological plates of BS treated thyroid revealed hypertrophy and thyroid follicular cell disruption with microcytic infiltration. Thiourea treated gland histological plate revealed complete abolition of normal histoarchitecture with marked changes in colloidal area and hyperplasia with folding and papillae on the epithelium. Conclusion: In overall, the data indicate that though the goitrogenic potentiality of BS cannot be considered having similar efficacy to that of thiourea but as a food entity by itself, it has potent antithyroidal activity even in presence of adequate iodine intake.