High iodine induces DNA damage in autoimmune thyroiditis partially by inhibiting the DNA repair protein MTH1

[helvella]

We see an awful lot of people "advised" (by anyone they talk to and most especially anyone who speaks beyond their understanding) to take iodine simply because the word "thyroid" has been mentioned in relation to their disorder. Doesn't seem to matter whether they have hyperthyroidism, hypothyroidism, cancer, whether it is primary, secondary or tertiary, autoimmune or diet-related. The universal assumption is that because the thyroid absorbs iodine, people should take more iodine.

There are bound to be circumstances in which some extra iodine might be helpful. But this paper suggests a potentially important reason for high iodine treatment to be avoided in autoimmune thyroiditis.

Of course, this is in mice, they don't have classic Hashimoto's, etc.

I certainly hope that follow-up research clarifies further. For now, this probably should be in the "hmm, that could be interesting" pile.

Cell Immunol. 2019 Jul 2:103948. doi: 10.1016/j.cellimm.2019.103948. [Epub ahead of print]

High iodine induces DNA damage in autoimmune thyroiditis partially by inhibiting the DNA repair protein MTH1.

Li F1, Wu Y2, Chen L2, Hu L2, Zhu F2, He Q2.

Author information

1 Thyroid Disease Diagnosis and Treatment Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310003, China. Electronic address: [e-mail].

2 Thyroid Disease Diagnosis and Treatment Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310003, China.

Abstract

This study aims to investigate the level of DNA damage in high iodine (HI)-induced autoimmune thyroiditis (AIT), and to explore the role of DNA repair protein MutT homolog-1 (MTH1) in this process. The levels of pro-inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-8 were measured using qRT-PCR and ELISA. The apoptosis was evaluated using TUNEL staining. The pathological changes of thyroid tissues were evaluated using hematoxylin and eosin (HE) staining. The DNA damage was assessed by determining the expression of 8-hydroxy-2'deoxyguanosine (8-OHdG; an indicator of oxidative DNA damage) and performing the Comet assay. Our results showed that both the HI-treated NOD.H-2h4 mice (experimental AIT mice) and the HI-treated mouse thyroid follicular epithelial cells showed enhanced inflammation, apoptosis, and DNA damage level, accompanied by decreased MTH1 expression. Importantly, overexpression of MTH1 effectively abrogated the HI-induced enhancement of inflammation, apoptosis, and DNA damage in mouse thyroid follicular epithelial cells. In conclusion, HI treatment induces DNA damage in AIT, at least in part, by inhibiting the DNA repair protein MTH1.

Copyright © 2019 Elsevier Inc. All rights reserved.

KEYWORDS:

Apoptosis; DNA damage; Inflammation; Iodine; MTH1

PMID: 31311621

DOI: 10.1016/j.cellimm.2019.103948

ncbi.nlm.nih.gov/pubmed/313...

[greygoose]

That is so true! So many people, doctors included, assume that iodine 'is good for' thyroid. Although, if asked, they have no idea in what way.

[TSH110 in reply to greygoose]

I read lack of iodine was once a common cause of thyroid disorder - hence the descriptor Derbyshire neck for a goitre. But iodine was added to table salt (and may be other things) and with this and water fluoridation autoimmune thyroiditis cases increased and iodine deficiency as a cause reduced. I presume it is correct. Why the old ideas persist despite these changes I don’t know but it seems a common theme for thyroid treatment - inappropriate approaches not in tune with current quality research and up to date scientific knowledge.

[greygoose in reply to TSH110]

Excess iodine can trigger Hashi's, yes. But, it seems that the medical profession is somewhat adverse to accepting new ideas, they love to cling on to the old beliefs. That said, they only hang onto the old beliefs if they serve their purpose!

[TSH110 in reply to greygoose]

Deffo not NDT! How I wish that were an old belief they had clung on to as a piece of ancient wisdom

[posthinking01 in reply to greygoose]

I was told to take Lugol's - and started very slowly - OMG - my thyroid went berserk - almost pulsating out of my neck - I tried it again several years later and same thing happened not for me I'm afraid - I have also had terrible difficulties finding a multi vitamin without iodine and choline which I know is good for you but I can't metabolise it as I have trimethylaminuria - I have received an e mail from a lovely family run supplement business who took on board what I said and have produced one - if anyone is interested in knowing about this supplement let me know and I will post.

[greygoose in reply to posthinking01]

Multi-vitamins aren't recommended, anyway, for several reasons, not just the iodine:

* If your multi contains iron, it will block the absorption of all the vitamins - you won't absorb a single one! Iron should be taken at least two hours away from any other supplement except vit C, which is necessary to aid absorption of iron, and protect the stomach.

* If your multi also contains calcium, the iron and calcium will bind together and you won't be able to absorb either of them.

* Multi's often contain things you shouldn't take or don't need : calcium, iodine, copper. These things should be tested before supplementing.

* Multi's often contain the cheapest, least absorbable form of the supplement : magnesium oxide, instead of magnesium citrate or one of the other good forms; cyanocobalamin instead of methylcobalamin; folic acid instead of methylfolate; etc. etc. etc.

* Multi's do not contain enough of anything to help a true deficiency, even if you could absorb them.

* When taking several supplements, you should start them individually at two weekly intervals, not all at once as you would with a multi. Because, if you start them all at once, and something doesn't agree with you, you won't know which one it is and you'll be back to square one.

With a multivitamin, you are just throwing your money down the drain, at best, and doing actual harm at worst. Far better to get tested for vit D, vit B12, folate and ferritin, and build up your supplementation program based on the results.

[posthinking01 in reply to greygoose]

They dont contain iron - or iodine - or copper - I agree with you - but for someone who can't afford to get tested it is something that could keep them ticking over - and I hate the statement that is often stated by the medical profession 'throwing your money down the drain' - I have been studying the science of nutrition for over 55 years and if it wasn't for supplements I would not be here now (as said to me by a consultant as he found out I had malnutrition issues even though I had a good diet) - if we were all tested by the NHS and had our deficiencies put back - the state of the nation's health would improve - most of the bad behaviour with the children today and criminal behaviour is down to diet. There is a wonderful organisation called FAB - food and behaviour institute who have been saying this for years and years but no-one will listen - far better to keep giving drugs. Because of my health issues I cannot take drugs other than antibiotics and a steroid - so I have had to control my symptoms with regular testing and putting back the deficiencies my body is showing. A multi vitamin tablet could just help people who were in need of some support - but I do agree that it is far better to test and only take what you need - but that is in an ideal world.

[greygoose in reply to posthinking01]

For the most part, I agree with all you say, there. But, that still doesn't make multis a good idea. Some things you just don't want to take too much of, like vit D and calcium - too much calcium is really a bad idea. It's rare to be calcium deficient in the western world, but I bet they put calcium in this multi, don't they? Everyone is obsessed with calcium, but too much can cause kidney stones and even heart attacks.

Then, there's the question of the quality of the ingredients. If, for example, they put magnesium oxide, instead of magnesium malate, for example, because it's cheaper, then you won't absorb it, so that's money wasted.

Sorry you don't like my expression 'throwing money down the drain' - it didn't come from a doctor in this case - but it does just about sum it up if you don't get any nutrition from the multi you've paid for.

[posthinking01 in reply to greygoose]

certainly agree about calcium and arterial issue - my brother in law has just had open heart surgery and they said his calcium levels were through the roof - now it could be that his parathyroid was out of sync but I suspect and did tell them not to take Cod LIver oil over a long period because it contained too much D.

[helvella in reply to TSH110]

Inadequate iodine is a major cause of thyroid disorder - almost certainly the principle cause around the world.

In the USA, and quite a number of other countries, iodised salt (or somethimes other foodstuffs) has helped address that issue.

But there just might be additiobal reasons for specific areas being goitre-prone. Some years ago the British Geological Survey did a major study of iodine and selenium in China. The picture was complicated.

[TSH110 in reply to helvella]

Thanks that is interesting. I though it was lack of seafood in the case of Derbyshire with it being well away from the coast but as you say it is probably far more complex

[helvella in reply to TSH110]

The furthest away from the coast is the Buckinghamshire/Oxfordshire/Northamptonshire area. If it were distance alone, wouldn't that be the worst area?

The simple fact that most of our food now travels considerable distances means everything has changed. For many, the water is piped long distances (e.g. Elan reservoirs to Birmingham) so any relation to local water supplies is much less obvious.

[TSH110 in reply to helvella]

The terrain is easier down there I believe than compared to the Peak District, so maybe that had some bearing on it. Yes the source of what we put into us is remarkable if we can even determine it. You never think tap water could be from somewhere else completely. I got the impression most hypothyrodism in the uk was not caused by iodine deficiency is that really the case?

It has stuck me as interesting that for many years prior to diagnosis with hypothyrodism I could not bear to eat salt not even a grain of it, but now I am taking thyroid replacement hormones I have regained a want for salt and find it very palatable. I use sea salt - I think the Cornish stuff in bigger crystals.

[Hidden in reply to helvella]

We always had iodised salt at home. I was told that there was risk of iodine shortage because it was a high moorland area with acid soil. Might that be true?

My grandmother had a goitre which apparently affected her heart, but I have no idea of the cause as she died over 70 years ago, before I was born

Where I live now is not far from the coastal source of laver bread, a local delicacy, and there are samphire beds within easy walking distance. But now I know (with the help of this forum) the risks of too much iodine...!

[helvella in reply to Hidden]

I do suspect there are issues like, as you suggest, the acidity of the soil.

Some atmospheric chemists have identifed that iodine is critical to the formation of clouds. Seems to imply that iodine actually can be related to rainfall. But high rainfall also washes minerals (which would include iodine) away.

[Clarrisa]

Has the number of people with a thyroid disorder & allergy (or sensitivity) to iodine been tallied? Maybe there is a subset of people who tolerate iodine much less. Similar to people who develop high iron levels & get potentially pushed into hemochromatosis or another blood dyscrasia thanks to iron fortified foods.

[Myro]

What a shit. ( Saham on me for not nice word).

Only sentence which I understand is title.

I'm tacking iodine. In my personal individually find out dose which is changing. It helps me a lot.

I'm not afraid of death. But quality of my life before iodine and with is 🌃 and dawn.

What is cousing changing DNA? Only thyroid cells ? Can anybody tell me what is consequence of high antibodies? Without treatment and with iodine tacking? If I'm right of them I will immediately subscribe to heppens fast. Even with radioactive ...

It is interesting how we blindly believe, trust nonsenses like that spinach has a lot of iron. I believed that hair loss is of male hormones. Nonsense. Women too. Bull ....

[Angel_of_the_North in reply to Myro]

Spinach DOES have a lot of iron, but it also has a lot of oxalic acid which blocks the iron from being absorbed. However, maybe Popeye told the truth as regulators are trying to stop a spinach extract being used by athletes as it too successful at increasing muscle strength.

Ecdysterone is the main compound in spinach extract. It is a phytosteroid — that is, a steroid that occurs naturally in plants and belongs to a class called phytosterols, which are "structurally similar to cholesterol."

Previous studies in mammals have shown that ecdysteroids have a wide range of beneficial effects. In the 1980s, researchers dubbed ecdysterone the "Russian secret," following suspicions that Russian Olympic athletes were using it as a performance boosting supplement.

medicalnewstoday.com/articl...

[Angel_of_the_North in reply to Myro]

Hair loss in both men and women can be caused by aromatization of testosterone to DHT, and it is a common cause of "male pattern" baldness in both sexes. But it is not the only cause.

[Myro in reply to Angel_of_the_North]

I'm male hair loss no more.

[Gingersnap202]

Being 80 years old, and from the US Midwest, I vividly recall from my youth, Old Ladies that had HUGE goiters on their necks. It is something no one sees here today, as the addition of iodine to salt has apparently solved the problem. ... That being the case, I wouldn't be dissing iodine so heavily if I were you guys. It is a necessary nutrient. If one isn't regularly eating sea food and/or using iodized salt, I'd say that you might want to do one or the other.

[helvella in reply to Gingersnap202]

Certinly iodine is vital. But the amount that most people might receive from iodised salt (in countries where that is usual - not the UK) is likely somewhere around 150 micrograms a day.

The quoted abstract refers to High Iodine - not just enough to be replete. And we see people taking staggering quanitites - like 30 millirgams a day, or more. We also see people suffering from things like amiodarone-induced thyroid issues (amiodarone being a medicine with very high iodine content), the consequences of iodine used as a disinfectant, injected iodine contrast media, as well as dosing with kelp, etc.

It is also important to factor in the very high percentage iodine in levothyroxine (T4) and liothyroine (T3). In many people, even what might have been a low iodine diet will be brought up to repletion by the addition of thyroid hormone.

I am absolutely NOT against diets which contain modest levels of iodine.

[Myro in reply to helvella]

You know what about you are talking. Explanation of troubles coused by iodine is in insufficient. Im curious to know what happened. How is it cured. Please do discribe.

[vocalEK in reply to Gingersnap202]

I grew up in the Goiter Belt of the U.S. Found this video about it: youtube.com/watch?v=HR2nDUV...(Not working as expected?)

[Gingersnap202]

Thank you for the clarification .. and ... I had not heard that liothyronine (T3) has iodine in it. ... I would try asking the makers of Cytomel about what amount of iodine is in my meds, but they aren't good about giving out information!

[helvella in reply to Gingersnap202]

The very name, T3, is derived from the fact that it has three atoms of iodine in each molecule of liothyronine.

Molecular formula: C15H11I3NNaO4

And levothyroxine, T4, has four atoms of iodine per molecule.

Molecualr formula: C15H11I4NO4

As iodine is a relatively heavy atom, the percentage by weight is very high.

There is no reason to ask your liothyronine makers - it is the same for all.

[helvella in reply to Gingersnap202]

You might care to view this document which describes the iodine content:

dropbox.com/s/6jfui0gt8q2ix...