Re: Cortisol's Effect on Iodine Uptake (was This is Iodine Grp)

[Guest guest]

In a nutshell:

1. Pig thyroid cells in a petri dish did show that hydorcortisol

increased the iodine uptake

2. The medium used in previous experiments was changed as the

researchers found it had an estrogenic effect & affected the test

detrimentally

3. Researchers found that RU486 stopped/slowed down hydrocortisol's

beneficial effect on iodine uptake

4. RU486 opposes both progesterone & cortisol because it has a high

affinity for their receptor sites. Because of this, it is useful for

emergency birth control, delaying menses, treating hypercortisonism

(Cushings) & for treating some cancers.

5. Because RU486 has an affinity for cortisol receptor sites, it could

have an adverse effect on thyroid function.

6. The increased iodine-uptake caused by hydrocortisone was dose-

dependant. More hydrocortisone increased uptake.

7. The hydrocortisone increases uptake thru cAMP-dependant pathways.

(I have come across this term in Google research. They mentioned

forskolin too, which is a supplement. Vasodialator, improves cAMP

function, indicated as an aid for increased eye pressure/glaucoma. I

came across it looking for glaucoma info. Anyway, more info here:

http://en.wikipedia.org/wiki/Forskolin)

8. Hydrocortisone did not increase TSH production

9. Dog & sheep thyroid cells have shown similar increases in iodine-

uptake with hydrocortisone.

10. Hydrocortisone at low concentrations inhibited iodine-uptake in

thyroid FRTL-5 cells & enhanced TSH production (sorry, I don't know

what FRTL-5 cells are. Quick Google didn't help)

11. The effect of hydrocortison on iodine-uptake depended on time of

exposure. Stimulation detected at 24hrs. Marked increase in iodine

uptake in 48-72hrs subsequent.

12. The type of medium & serum used for culture affected the results.

Pretreatment of the serum with charcoal and incubation in serum-free

medium removed factors, such as glucocorticoids, and other steroid

hormones. Thus, prior tests without the medium adjusted to limit these

effects might explain why some other research found different results.

Is that synopsis clear as mud?

>

> one thing i am specifically interested in determining along these

> lines is how cortisol levels (high or low)...affect iodine uptake.

>

> maybe i can find some info in this article I came across this

> morning regarding Hydrocortisone and its effect on Iodine

> Uptake...but some of these are journal articles are hard to decipher

> for me. comments on this one appreciated.

>

> http://endo.endojournals.org/cgi/reprint/135/5/1972.pdf

>

> cindi

>

[Guest guest]

, this is great! Thank you!! Zoe

----- Original Message -----

From: jtb14789

In a nutshell: 1. Pig thyroid cells in a petri dish did show that hydorcortisol increased the iodine uptake 2. The medium used in previous experiments was changed as the researchers found it had an estrogenic effect & affected the test detrimentally 3. Researchers found that RU486 stopped/slowed down hydrocortisol's beneficial effect on iodine uptake 4. RU486 opposes both progesterone & cortisol because it has a high affinity for their receptor sites. Because of this, it is useful for emergency birth control, delaying menses, treating hypercortisonism (Cushings) & for treating some cancers.5. Because RU486 has an affinity for cortisol receptor sites, it could have an adverse effect on thyroid function. 6. The increased iodine-uptake caused by hydrocortisone was dose-dependant. More hydrocortisone increased uptake. 7. The hydrocortisone increases uptake thru cAMP-dependant pathways. (I have come across this term in Google research. They mentioned forskolin too, which is a supplement. Vasodialator, improves cAMP function, indicated as an aid for increased eye pressure/glaucoma. I came across it looking for glaucoma info. Anyway, more info here: http://en.wikipedia.org/wiki/Forskolin) 8. Hydrocortisone did not increase TSH production9. Dog & sheep thyroid cells have shown similar increases in iodine-uptake with hydrocortisone. 10. Hydrocortisone at low concentrations inhibited iodine-uptake in thyroid FRTL-5 cells & enhanced TSH production (sorry, I don't know what FRTL-5 cells are. Quick Google didn't help) 11. The effect of hydrocortison on iodine-uptake depended on time of exposure. Stimulation detected at 24hrs. Marked increase in iodine uptake in 48-72hrs subsequent. 12. The type of medium & serum used for culture affected the results. Pretreatment of the serum with charcoal and incubation in serum-free medium removed factors, such as glucocorticoids, and other steroid hormones. Thus, prior tests without the medium adjusted to limit these effects might explain why some other research found different results.Is that synopsis clear as mud?

[Guest guest]

well...at least it's shorter than the actual article...and i think I

will be able to comprehend your statements after a few readings.

thank you.

cindi

>

> > Is that synopsis clear as mud?

[Guest guest]

You're welcome. But my eyes, my eyes! I've gone blind reading thru

that article

If anyone else wants to take a perusal to see if I missed or

misinterpreted any salient points, have at it. Some of it I just

skimmed for major points. I would have had to put a lot more time &

concentration in to absorb all the biological minutia.

>

> , this is great! Thank you!! Zoe

> ----- Original Message -----

> From: jtb14789

>

>

[Guest guest]

The synopsis is pretty darn clear. I think where the water gets muddy

is in the chicken/egg department...

For those of us with adrenal & thyroid problems, was it the sluggish

adrenals, i.e., low cortisol, that started the whole cascade,

including possible iodine deficiency?

That would be an interesting study for one of the pros on the list!

>

> In a nutshell:

>

> 1. Pig thyroid cells in a petri dish did show that hydorcortisol

> increased the iodine uptake

>

> 2. The medium used in previous experiments was changed as the

> researchers found it had an estrogenic effect & affected the test

> detrimentally

>

> 3. Researchers found that RU486 stopped/slowed down hydrocortisol's

> beneficial effect on iodine uptake

>

> 4. RU486 opposes both progesterone & cortisol because it has a high

> affinity for their receptor sites. Because of this, it is useful for

> emergency birth control, delaying menses, treating hypercortisonism

> (Cushings) & for treating some cancers.

>

> 5. Because RU486 has an affinity for cortisol receptor sites, it could

> have an adverse effect on thyroid function.

>

> 6. The increased iodine-uptake caused by hydrocortisone was dose-

> dependant. More hydrocortisone increased uptake.

>

> 7. The hydrocortisone increases uptake thru cAMP-dependant pathways.

> (I have come across this term in Google research. They mentioned

> forskolin too, which is a supplement. Vasodialator, improves cAMP

> function, indicated as an aid for increased eye pressure/glaucoma. I

> came across it looking for glaucoma info. Anyway, more info here:

> http://en.wikipedia.org/wiki/Forskolin)

>

> 8. Hydrocortisone did not increase TSH production

>

> 9. Dog & sheep thyroid cells have shown similar increases in iodine-

> uptake with hydrocortisone.

>

> 10. Hydrocortisone at low concentrations inhibited iodine-uptake in

> thyroid FRTL-5 cells & enhanced TSH production (sorry, I don't know

> what FRTL-5 cells are. Quick Google didn't help)

>

> 11. The effect of hydrocortison on iodine-uptake depended on time of

> exposure. Stimulation detected at 24hrs. Marked increase in iodine

> uptake in 48-72hrs subsequent.

>

> 12. The type of medium & serum used for culture affected the results.

> Pretreatment of the serum with charcoal and incubation in serum-free

> medium removed factors, such as glucocorticoids, and other steroid

> hormones. Thus, prior tests without the medium adjusted to limit these

> effects might explain why some other research found different results.

>

> Is that synopsis clear as mud?

>

>

>

>

[Guest guest]

Terrific shortest summary!!!

The other detail I found interesting is that cortisol appears to increase iodine uptake the same way TSH does: through the cAMP pathway. (Don't ask me to explain that.... Just thought it was interesting that it is the same path. Maybe it is time for me to try to understand the cAMP pathway....)

The first step is the cortisol receptor in the thyroid cell. Some medications (e.g., mifepristone) block this receptor and therefore block the effects of cortisol on iodine intake.

Zoe

----- Original Message -----

From: jtb14789

Shorter version - preliminary research with animal thyroid cells in petri dishes shows cortisol can indeed improve iodine uptake

[Guest guest]

>

> Posted by: " jtb14789 " jtb14789@... jtb14789

>

>

> Hi ,

> Am I right in reading that iodine uptake is effected differently

> depending on 1) dose (low dose cortisone=iodine inhibition; high

> dose=increase)

Then would that mean the a person with a thyroid condition and a blood

sugar issue - since I recently learned that low blood sugar increases

cortisol - would need less thyroid medication, if their cortisol rose

over time, due to increased iodine uptake?

It would seem that based on cortisol, especially in the case of

adrenal fatigue, that both thyroid medication and iodine dosing most

likely would not be able to remain static. Am I getting the right

idea here?

[Guest guest]

which i think is what thyroidmanager.org says too, but because the

gland is partially destroyed...but then i think this also says

iodine depletion protects against hashimoto's...and so then I get

confused about whether a hashi's person on full relacement needs

high dose iodine at all. why is this so confusing..and so any

differing thoughts on hashi's and iodine?

http://www.thyroidmanager.org/chapter8/8__iodide_metabolism.htm

Iodide Metabolism and Effects

Many patients with Hashimoto's thyroiditis do not respond to

injected TSH with the expected increase in RAIU or release of

hormone from the gland(81). These findings probably mean that the

gland is partially destroyed by the autoimmune attack and is unable

to augment iodine metabolism further. Further, the thyroid gland of

the patient with Hashimoto's disease does not organify normally(82)

(Fig. 8-4). Administration of 400 mg potassium perchlorate 1 hour

after giving a tracer iodide releases 20 - 60% of the glandular

radioactivity. Also, a fraction of the iodinated compounds in the

serum of patients with Hashimoto's thyroiditis is not soluble in

butanol, as are the thyroid hormones, but is an abnormal peptide-

linked iodinated component. This low-weight iodoprotein is probably

serum albumin that has been iodinated in the thyroid gland. A

similar iodoprotein is also found in several other kinds of thyroid

disease, including carcinoma, Graves' disease, and one form of

goitrous cretinism. It may be formed as part of the hyperplastic

response. TG is also detectable in their serum.

Iodide is actively transported from blood to thyrocytes and recently

the sodium / iodide symporter (NIS) has been cloned. Antibodies

against NIS were found in autoimmune thyroid disease(83). This

antibody has an inhibitory activity on iodide transport and may

modulate the thyroid function in Hashimoto's thyroiditis. More

recent studies reported rather low prevalence (less than 10%) of

anti-NIS antibodies in Hashimoto's disease and clinical relevance is

still unknown(84),(85).

In animal experiment iodine depletion prevents the development of

autoimmune thyroiditis(86). It is suggested that mild iodine

deficiency partly protect against autoimmune thyroid disease(87),

although it is controversial(88). In a region where iodine-

containing food (such as seaweed) is common, as in Japan, excessive

dietary iodine intake (1000 micro g/day or more) may cause transient

hypothyoidism in patients with subclinical autoimmune thyroiditis.

This condition is easily reversible with a reduction in iodine intake

(89). Iodine is important not only for thyroid hormone synthesis but

also for induction and modulation of thyroid autoimmunity. In

general, iodine deficiency attenuates, which iodine excess

accelerates autoimmune thyroiditis in autoimmune prone individuals

(90). In animal experiment, it is revealed that enhanced iodination

of thyroglobulin facilitates the selective processing and

presentation of a cryptic phatogenic peptide in vivo or in vitro.

Moreover, it is suggested that iodine excess stimulates thymus

development and effects function of various immune cells(91).

>

>

>

> It would be hard to quantify the relationship. From what Zoe's

posted

> recently, which kind of agrees with what Dr. Derry said,

that when one

> is on thyroid medication, iodine won't affect the thyroid because

it's " shut

> off " in regard to iodine intake So, I'm not sure if anyone will

really know

> their true thyroid status without going off their thyroid meds,

which is a

> little problematic.