7 research outputs found
Effect of cassava (Manihot esculenta crentz) on thyroid status under conditions of varying iodine intake in rats
Cassava (Manihot esculenta Crantz), a widely used common vegetable of Indian origin contains dietary goitrogens. Goitrogenic content, in vitro anti-thyroidal activity and in vivo antithyroid potential of fresh and cooked cassava of Indian origin in albino rats with and without iodine supplementation were evaluated in this study. In vitro inhibition of thyroid peroxidase (TPO )activity was found with fresh and cooked cassava extract but the presence of extra iodide in the incubation media had shown reduction in such inhibition to an extent. Inhibition constant (IC50) and PTU equivalence of fresh cassava were 42.5 ± 1.35µg and 2.21 respectively. After consumption, cyanogenic constituents in cassava are metabolized to thiocyanate and iodine-retaining capacity seems to be dependent on thiocyanate exposure. In cassava fed rats, the urinary iodine concentration resembled the state of adequate iodine nutriture but thyroid gland fails to utilize available iodine. Increased thyroid weight (P < 0.001), inhibited thyroid peroxidase (TPO) activity and reduced thyroid hormone profiles (P < 0.001) were noted in fresh and cooked cassava fed rats, resembling a relative state of morphological as well as biochemical hypothyroidism even in presence of adequate iodine. African Journal of Traditional, Complementary and Alternative Medicines Vol. 3(3) 2006: 87-9
Effect of bamboo shoot, <i>Bambusa arundinacea </i>(Retz.) Willd. on thyroid status under conditions of varying iodine intake in rats
781-786Young shoots or sprouts of common bamboos
are used as food in third world countries. Evidences suggest the presence of
cyanogenic glucoside like anti-thyroidal substance in bamboo shoots (BS) but
effect of prolonged BS consumption on thyroid status under conditions of varying
iodine nutriture remains unexplored. The study was undertaken to evaluate goitrogenic
content, in vitro anti thyroid peroxidase (TPO) activity and in vivo anti
thyroid potential of BS with and without extraiodide. Fresh BS contains high cyanogenic
glucoside (551 mg/kg), followed by thiocyanate (24mg/kg) and glucosinolate
(9.57mg/kg). In vitro inhibition in TPO activity was found with raw, raw
boiled and cooked extracts.
Inhibition constant (IC50) and
PTU equivalence of fresh BS were 27.5±0.77 pg and 3.27 respectively. Extra iodide
in the incubation media reduced TPO inhibition induced by BS but could not cancel
it. Thyroid weight, TPO activity and total serum thyroid hormone levels of BS fed
animals for 45 and 90 days respectively were determined and compared with controls.
Significant increase in thyroid weight as well as higher excretion of thiocyanate
and iodine along with marked decrease in thyroid peroxidase activity, T4 and T3
levels were observed in BS fed group. Chronic BS consumption gradually developed
a state of hypothyroidism. Extra iodide had reduced the anti-thyroidal effect of
BS to an extent but could not cancel it because of excessive cyanogenic glucoside,
glucosinolate and thiocyanate present in it
Effect of radish (<i style="">Raphanus sativus </i>Linn.) on thyroid status under conditions of varying iodine intake in rats
653-661Cruciferous plants viz. cabbage,
cauliflower, turnip, radish, mustard etc. that contain goitrogenic/antithyroid
substances, constitute a portion of regular human diet. The effect of chronic
feeding of fresh and cooked radish, R.
sativus under varying state of iodine intake on morphological and
functional status of thyroid in albino rats was evaluated by thyroid gland
morphology and histology, thyroid peroxidase activity, serum triiodothyronine,
thyroxine and thyrotropin levels. The consumption pattern of iodine and
goitrogens of cyanogenic origin was evaluated by measuring urinary iodine and
thiocyanate levels respectively. After chronic radish feeding, increased weight
of thyroid gland, decreased thyroid peroxidase activity, reduced thyroid
hormone profiles and elevated level of thyrotropin were observed resembling a
relative state of hypoactive thyroid gland in comparison to control even after
supplementation of adequate iodine