ME/CFSウェブセミナー 第5弾 MEと痛み

broadcast on November 30th, 2012

 

The pains change during the disorder. Most patients who recall how they felt before the disease or in the run-up of the disease, remember they were free of pain in the beginning. The fatigue and the lack of recovery often occur before the start of the pain.

 

The various possible causes of pain are of a central nature. That is, cytokines, which are particles produced by our own white blood cells, can affect certain receptors and induce pain. This concerns mainly the so-called inflammatory cytokines, with one specific pointer to interleukin 1. They also occur in other disorders and animal models, and are accompanied by pain of central origin.

 

Bacterial neurotoxins also play a part. When the immune system has been seriously disrupted, all kinds of bacteria no longer can be eliminated. Or intestinal bacteria pop up, because the intestines are less capable of holding them back. Bacterial toxins can also cause central pain. Moreover there are a lot of other substances, such as nitrogen oxide, which play a role. We know for example that if we reduce the effects of nitrogen oxide, pain is also reduced. The same applies to a number of antibiotics that inhibit certain bacteria and also reduce pain.

 

There is also a problem with the opiate receptors. Endogenous opiates play a part in the brain, and with those receptors there seems to be a problem too. An English group is engaged in manipulating those opiate receptors, as to also reduce pain in patients.

 

Perhaps the most important cause of pain is metabolic pain, pain from the metabolism. It is caused by a poor delivery of oxygen to the organs and also by mitochondrial dysfunction. The mitochondria are responsible for the release of ATP to let all our organs function.

 

This is the most difficult pain to combat and the biggest problem, because there is no medicine for it. We can try to ensure the peripheral parts of the body getting more oxygen. We can do that artificially. But the release of several substances causing the large blood vessels to expand, automatically causes a contraction of the small blood vessels. Which is the cause of the cold feeling in the peripheral organs like fingers and feet, because the blood vessels themselves contract.

 

This is a result of an altered sympathetic nervous system that is more active as compensation, but still can’t prevent H2S, NO and other vasoactive substances to cause expansion of the large blood vessels. To such an extent that the small blood vessels are contracting. I think many organs suffer from a chronic oxygen shortage. And this will also cause a shortage of oxygen in the peripheral nerves – which contain blood vessels as well.

 

So we have a mixture of neuropathic and metabolic pain. In my experience metabolic pain is the biggest problem because you can’t cure it. Simply because there’s an imbalance in the blood circulation.

 

Then there are all kinds of other factors. With this condition the red blood cells aren’t functioning normally, and there is also a problem with oxygen supply. I could mention an entire list of different mechanisms which all come down to the same. We call them ischemic pains, due to a shortage of oxygen to form energy. The result, of course, is also the production of much lactic acid. We and others have found the concentration of lactic acid in the blood to be up to three times the normal value while resting. In normal blood 0.6 to 1 mmol lactic acid per litre is found. In a ME patient it is not uncommon to find 2 to 2.5 mmol per litre. And that’s a

broadcast on November 30th, 2012

The pains change during the disorder. Most patients who recall how they felt before the disease or in the run-up of the disease, remember they were free of pain in the beginning. The fatigue and the lack of recovery often occur before the start of the pain.

 

The various possible causes of pain are of a central nature. That is, cytokines, which are particles produced by our own white blood cells, can affect certain receptors and induce pain. This concerns mainly the so-called inflammatory cytokines, with one specific pointer to interleukin 1. They also occur in other disorders and animal models, and are accompanied by pain of central origin.

 

Bacterial neurotoxins also play a part. When the immune system has been seriously disrupted, all kinds of bacteria no longer can be eliminated. Or intestinal bacteria pop up, because the intestines are less capable of holding them back. Bacterial toxins can also cause central pain. Moreover there are a lot of other substances, such as nitrogen oxide, which play a role. We know for example that if we reduce the effects of nitrogen oxide, pain is also reduced. The same applies to a number of antibiotics that inhibit certain bacteria and also reduce pain.

 

There is also a problem with the opiate receptors. Endogenous opiates play a part in the brain, and with those receptors there seems to be a problem too. An English group is engaged in manipulating those opiate receptors, as to also reduce pain in patients.

 

Perhaps the most important cause of pain is metabolic pain, pain from the metabolism. It is caused by a poor delivery of oxygen to the organs and also by mitochondrial dysfunction. The mitochondria are responsible for the release of ATP to let all our organs function.

 

This is the most difficult pain to combat and the biggest problem, because there is no medicine for it. We can try to ensure the peripheral parts of the body getting more oxygen. We can do that artificially. But the release of several substances causing the large blood vessels to expand, automatically causes a contraction of the small blood vessels. Which is the cause of the cold feeling in the peripheral organs like fingers and feet, because the blood vessels themselves contract.

 

This is a result of an altered sympathetic nervous system that is more active as compensation, but still can’t prevent H2S, NO and other vasoactive substances to cause expansion of the large blood vessels. To such an extent that the small blood vessels are contracting. I think many organs suffer from a chronic oxygen shortage. And this will also cause a shortage of oxygen in the peripheral nerves – which contain blood vessels as well.

 

So we have a mixture of neuropathic and metabolic pain. In my experience metabolic pain is the biggest problem because you can’t cure it. Simply because there’s an imbalance in the blood circulation.

 

Then there are all kinds of other factors. With this condition the red blood cells aren’t functioning normally, and there is also a problem with oxygen supply. I could mention an entire list of different mechanisms which all come down to the same. We call them ischemic pains, due to a shortage of oxygen to form energy. The result, of course, is also the production of much lactic acid. We and others have found the concentration of lactic acid in the blood to be up to three times the normal value while resting. In normal blood 0.6 to 1 mmol lactic acid per litre is found. In a ME patient it is not uncommon to find 2 to 2.5 mmol per litre. And that’s a normal value in the blood of someone who’s running the marathon of Rotterdam at considerable speed. In ME patients this is a normal value when at rest. That lactic acid comes from tissues, which must convert all their glucose in lactic acid as a final product. With much less energy supply.

 

As we have shown in a publication on the other hand there are also intestinal bacteria which produce both left- as right-turning lactic acid. Often the disintegration of D-lactate (animal lactic acid) is more difficult with ME patients because they lack the enzymes to do so.

 

So there are a lot of factors which cause the aerobic metabolism to shift to a more anaerobic metabolism. And to me this is also an important element in the occurring pain. That’s why pain management must be performed with an overall vision on pain. Often one can’t cure this with one particular medicine, but with a more integrated approach one can usually cause a serious relief from the pains.

2012年11月30日放送

 

痛みは、病中に変化していきます。ほとんどの患者は発症前や発病当初にどんな感じだったかを覚えていて、最初のうちは痛みがなかったと記憶しています。疲労感と疲労から回復しない状態がしばしば痛みよりも先行していることが多いようです。

 

痛みの様々な原因は、中枢神経系からきています。というのは、私たちの白血球によって産出されるサイトカインが、ある受容体に影響を及ぼし、痛みを引き起こしているのです。主に、炎症性サイトカインと呼ばれるもので、ことに、インターロイキン1が特に注目されています。これらは他の疾患や動物モデルにも見られるもので、中枢神経を起源とする痛みを引き起こします。

 

細菌性神経毒素もまた関与しています。免疫系が深刻に乱れているとき、多種の細菌がもはや消滅されなくなります。または、腸が腸内細菌を阻止する力が弱まるため、腸内細菌が飛び出てしまうのです。細菌性毒素もまた中枢神経系の痛みを引き起こします。

 

さらに、他にも、窒素酸化物などの多くの他の物質が関与していることもあります。たとえば、もし、窒素酸化物からくる影響を減少させると、痛みも軽減することがわかっています。多くの抗生物質にも同じことが言えて、ある種の細菌を抑制することで痛みを軽減することができます。

 

オピエート受容体にもまた問題があります。内因性オピエート(体内アヘン)は脳に作用しますが、これらの受容体にも問題があるようです。イギリスの研究グループは、これらのオピエート受容体をコントロールすることで患者の痛みを軽減する試みに従事しています。

 

もしかすると最も重要な痛みの原因は代謝性の痛みかもしれません。この痛みは、器官への酸素の供給不足やミトコンドリアの機能障害によっても生じます。ミトコンドリアは、私たちの臓器が機能するためにATP(アデノシン三リン酸)を放出する役割をになっています。

 

これが闘うのに最も難しい痛みで最大の問題です。なぜなら、それに対処する薬が存在しないからです。人工的に、体の末端部位がもっと酸素を得られるようにすることはできます。しかし、いくつかの物質の放出されると、大きな血管が拡張し、自動的に小さな血管の収縮が引き起こされます。これが、指や足などの末梢器官の冷感の原因になります。なぜなら、血管自体が収縮しているからです。

 

これは、より活発化した交感神経系の異常のせいで、H2SやNOや他の血管作動性物質が大きな血管を拡張させるのを防ぐことができず、小さな血管は収縮します。私は、多くの器官が慢性の酸欠状態に陥っていると思っています。このことが、血管を含む末梢神経の酸素不足を引き起こしているのです。

 

このように、(ME患者の痛みには)神経障害的な痛みと代謝系の痛みが交じり合っているのです。治癒することができない代謝系の痛みのほうが最も重大な問題だと私の経験上感じています。単にそこには血液循環の不均衡があるからです。

 

そして、(ME患者の痛みには)他にも多くの別の要素が絡み合っています。この病気では、赤血球が正常に機能しておらず、ここでも酸素供給の問題が生じています。私たちは、この痛みをエネルギー産出のために酸素が不足することによって起こる“虚血性の痛み”と呼んでいます。結果として、もちろん、多くの乳酸の生成が起こります。私たちだけでなく、他の研究者たちも、ME患者の安静時の血中の乳酸濃度が正常値の3倍までにものぼることを発見しています。健康な人の血液では、1リットルに0.6から1mmolの乳酸が見つかりました。ME患者では、1リットル中に2から2.5mmolが見つかるのも珍しくありません。この値は、かなりのスピードで“ロッテルダムマラソン”を走った人の標準的な血中濃度に値するものです。ME患者では、この値が安静時の値なのです。乳酸は、組織がぶどう糖を代謝する際に最終的に生成されるものですが、(ME患者では)非常に少ないエネルギー代謝で生成されるのです。

 

その横で、私たちが発表してきたように、左旋性と右旋性の乳酸の両方を生成する腸内細菌があることもわかっています。しばしば、ME患者は分解に必要な酵素の欠乏により、D乳酸(動物性乳酸)の分解がより難しいのです。

 

このように、ME患者には好気性代謝が、より嫌気性代謝の方向へ移行することを引き起こす様々な要因があります。私は、このことが痛みの発生において、重要な要素だと考えています。これが、痛みの管理は全体像を考慮したうえで行われるべきだと思う理由です。ある一つの特定の薬によってこれを治すことはできませんが、もっと統合的なアプローチによって痛みから実際に解放される方法を見出すことができるのです。