Goitrin

Chem Senses. 2010 Oct;35(8):685-92.

Genetics and bitter taste responses to goitrin, a plant toxin found in vegetables.[Pubmed: 20551074]

The perceived bitterness of cruciferous vegetables such as broccoli varies from person to person, but the functional underpinnings of this variation are not known. Some evidence suggests that it arises, in part, from variation in ability to perceive Goitrin (5-vinyloxazolidine-2-thione), a potent antithyroid compound found naturally in crucifers.
METHODS AND RESULTS:
Individuals vary in ability to perceive synthetic compounds similar to Goitrin, such as 6-propyl-2-thiouracil (PROP) and phenylthiocarbamide (PTC), as the result of mutations in the TAS2R38 gene, which encodes a bitter taste receptor. This suggests that taste responses to Goitrin itself may be mediated by TAS2R38. To test this hypothesis, we examined the relationships between genetic variation in TAS2R38, functional variation in the encoded receptor, and threshold taste responses to Goitrin, PROP, and PTC in 50 subjects. We found that threshold responses to Goitrin were associated with responses to both PROP (P = 8.9 x 10(-4); r(s) = 0.46) and PTC (P = 7.5 x 10(-4); r(s) = 0.46). However, functional assays revealed that Goitrin elicits a weaker response from the sensitive (PAV) allele of TAS2R38 (EC(50) = 65.0 μM) than do either PROP (EC(50) = 2.1 μM) or PTC (EC(50) = 1.1 μM) and no response at all from the insensitive (AVI) allele. Furthermore, Goitrin responses were significantly associated with mutations in TAS2R38 (P = 9.3 × 10(-3)), but the same mutations accounted for a smaller proportion of variance in Goitrin response (r(2) = 0.16) than for PROP (r(2) = 0.50) and PTC (r(2) = 0.57).
CONCLUSIONS:
These findings suggest that mutations in TAS2R38 play a role in shaping Goitrin perception, but the majority of variance must be explained by other factors.

J Nat Prod. 1988 Sep-Oct;51(5):862-5.

Inhibition of dopamine beta-hydroxylase by goitrin, a natural antithyroid compound.[Pubmed: 2462616]

METHODS AND RESULTS:
RS-Goitrin can be conveniently prepared by a simplification of the Ettlinger procedure. Goitrin is a moderate inhibitor of purified bovine adrenal dopamine beta-hydroxylase. The administration of Goitrin leads to a depression of brain norepinephrine and to an elevation of heart and adrenal dopamine.

Food Chem Toxicol. 1990 Feb;28(2):81-8.

Glutathione S-transferase subunit induction patterns of Brussels sprouts, allyl isothiocyanate and goitrin in rat liver and small intestinal mucosa: a new approach for the identification of inducing xenobiotics.[Pubmed: 2341092]

Effects of Brussels sprouts (2.5-30%), allyl isothiocyanate (0.03 and 0.1%) and Goitrin (0.02%), in the diet, on the glutathione S-transferase subunit pattern in the liver and small intestinal mucosa of male Fisher rats were investigated.
METHODS AND RESULTS:
A statistically significant linear relationship was found between the amount of Brussels sprouts in the diet and the induction of glutathione S-transferase subunits in two experiments. Increases in total activity of glutathione S-transferases towards 1-chloro-2,4-dinitrobenzene ranged from about 15% (2.5% Brussels sprouts in the diet) to 180% (30% Brussels sprouts in the diet) in the liver, and from 3% (2.5% Brussels sprouts) to 150% (30% Brussels sprouts) in the small intestinal mucosa. There were similar increases in the total amounts of glutathione S-transferase subunits. In the first experiment, when the average sinigrin and proGoitrin levels found in the sprouts were 1835 and 415 mumol/kg, respectively, subunit induction patterns in both the liver and the small intestinal mucosa were very similar to the pattern observed after feeding allyl isothiocyanate. In the second experiment, when the average sinigrin level found in the sprouts was as low as the proGoitrin level (both about 540 mumol/kg), a Goitrin-like induction pattern was observed. The most pronounced difference between the glutathione S-transferase subunit induction patterns due to administration of allyl isothiocyanate and Goitrin is the much stronger enhancement of subunit 2 by allyl isothiocyanate.
CONCLUSIONS:
The induction patterns of both experiments indicate that in Brussels sprouts at least two compounds, probably allyl isothiocyanate and Goitrin, are responsible for the induction of glutathione S-transferases.

Z Lebensm Unters Forsch. 1985 Nov;181(5):375-8.

The occurrence of goitrogenic substances in milk. 1. Release of goitrin in the milk of cows fed on rapeseed extract cakes.[Pubmed: 2416146]

METHODS AND RESULTS:
A total of six cows, divided into 3 groups, were fed various amounts of rape cake containing 6 g of Goitrin/kg over a period of 7 days. The cows were milked twice a day and the Goitrin content of the heated milk samples were determined by a HPLC-method within 2 h. When rape cake was fed at 0.39, 1.9 and 3.9% resp. of the total feed this resulted in medium Goitrin values of 37, 163 and 707 micrograms/l milk. These values correspond to a transfer of about 0.1% of the original proGoitrin content in the feed. 12 h after the last rape feeding the amount of Goitrin in the milk was below the detection limit of 7 ppb. The toxicological significance of these findings are dicussed.