11. What Might Cause ME? (Part 2)

Ideas about how ME might be caused by an infection &/or and inflammation in the brain or spine; or the immune system not working properly; or the mitochondria not producing energy properly in the cells; or the hypothalamus, pituitary and adrenal glands (the HPA axis) not working properly; or a combination of these - in response to viral, environmental, and other possible triggers. 

 

Hello again! The symptoms of ‘long-term fatigue’ can be caused by all sorts of things. They can be down to being ‘generally run-down’, or stress, or not getting enough nutrition in the diet. Some degree of depression, or some other undiagnosed illness or underlying cause - or even needing to do more exercise or activity - can also be a factor. But those things are not the same as ME.

After anyone has had quite a serious virus or other infection (including flu or glandular fever), then it’s pretty common to carry on feeling ‘less than 100%’ for some time, with exhaustion, illness and weakness. But most people recover from this ‘post-viral fatigue’ (PVF) within a few weeks or a handful of months at the most. That is not in itself the same thing as ME, - which is a lot more severe, and prolonged, not getting better after several months.

ME - Myalgic Encephalomyelitis, also called ‘Chronic Fatigue Syndrome’ - ‘officially’ at the moment only gets diagnosed after 6 months, and after other illnesses have been ruled out. So it could actually encompass a range of conditions - sometimes with some quite different symptoms from person to person - but always with the characteristic cognitive brain symptoms, and feeling really ill after any activity (so called ‘post-exertional neuro-immune exhaustion’ or PENE), sleep problems, immune symptoms, and pain, or dysautonomic or hormone or hypersensitivity symptoms. So, as I see it, ME is a specific, severe cause of so-called ‘chronic fatigue’, and which seems to be characterised by a physiological dysfunction of the brain and central nervous system, and of the immune system, and of the mitochondria producing energy in cells throughout the body and muscles.

There are a few different theories about the causes and mechanisms involved with ME, and I think that several of them could really be overlapping parts of the jigsaw of understanding this complex illness. So many of the body’s different systems all seem to be out of equilibrium or not working properly. I guess it’s a bit of a ‘chicken and egg’ question as to which problems cause which other ones - what’s the primary thing that’s gone wrong, and what are the secondary effects - or because they could all be interlinked vicious circles, how do they start, and how do you stop them again? I’m not a doctor, I’m an engineer - and I’m not able to read all the research about ME and other illnesses - there are plenty of websites, forums and Facebook groups if you want to - but the main ideas, to me, seem to be these:

1. It might be that there is a persistent neurological infection, perhaps like a polio or herpes virus, or a virus that hasn’t been identified yet, that is still active in the brain or the spine and nervous system. Or it may have damaged some part of the brain or nervous system - although not necessarily permanently. There might be an entero-virus - or possibly toxins - that enter the blood via the gut, and which then cross over into the brain and nerves. It could be that there are ongoing effects of an infection like that, even after the infection has gone, similar to “post-polio syndrome”.

2. It might be that the immune system has been damaged somehow, so it continues to behave as if it is still reacting to a severe infection, whether that infection is still present or not. And it could be that the interaction between the immune system and the nervous system has been damaged, how they “send messages” to each other. It’s possible that this, in turn, could be caused by something else underlying it, like a retro-virus, such as XMRV.

3. Or there might be damage to muscle and nerve tissues, possibly through viral attack or toxins or other physical stresses - or it might be that the way that mitochondria in the cells throughout the body ‘make’ energy has broken down and won’t work properly. This could explain in people with ME the wide ranging fatigue and lack of stamina in the muscles, and having to rest for ages to recover from that exhaustion. If the mitochondria in the brain are affected too, it could explain all the other symptoms, and in the heart, it could explain the low blood output, being less efficient at carrying oxygen where it is needed around the body. Or the mitochondria not working could all be secondary, caused by the other things.

Personally, I think that all three of those general mechanisms could be at play: 1. an infection and inflammation in the brain or spine; 2. the immune system not working properly; and 3. the mitochondria not producing energy properly in the cells.

But what I believe could be at the root of ME is the hypothalamus gland. That, and the pituitary and adrenal glands - the so-called ‘HPA axis’ - have been shown to be significantly disturbed in people with ME.

The adrenal glands, which sit on top of our kidneys, are responsible for the hormones in our bodies when we react to stress, whether that’s physical or emotional stresses. There’s sudden stress, producing adrenaline, the ‘fight or flight’ response, - and there’s balancing ongoing stresses, producing the steroids cortisol and DHEA. The adrenal glands also affect the water / salt balance in our bodies, and blood pressure, the digestive system, and can affect sex hormones.

The pituitary gland, inside the brain, is basically the body’s ‘supercomputer’. It’s the ‘master gland’, regulating pretty much everything to do with hormones that goes on in the body. It controls the adrenal glands and stress response, as well as the thyroid - a lot of people with ME seem to have either borderline overactive thyroid glands (and very fast metabolism, low blood pressure and are underweight), or borderline underactive thyroids (with very slow metabolism, high blood pressure, and problems with excessive fluid retention). The pituitary also controls growth hormones, sex hormones, and helps to keep things in equilibrium like metabolism and converting food into energy and how the cells’ mitochondria work. It also regulates body temperature, blood pressure, blood sugar levels, heart rate, and the immune system. The pituitary also makes endorphins, which are associated with sensations of feeling happy or even “on a high”, as well as relieving pain, in response to exercise, stress, excitement, pleasure, and even listening to music, or eating chocolate or chillies!

And the hypothalamus gland, inside the brain, is in effect the ‘input’ into the pituitary. So if the hypothalamus has gone wrong, then everything that the pituitary, and adrenal glands, are responsible for, goes wrong too. The hypothalamus acts like the body’s thermostat for everything, collecting feedback from everything that’s going on in and around the body, via hormones and the nervous system, as well as information from outside the body, via all of the senses, including daylight (affecting sleep patterns), and infections, and more. It seems to me that in ME, it’s like the hypothalamus - the brain’s ‘volume knob’ - is constantly stuck on maximum - or higher! - possibly because the hypothalamus itself is inflamed or has a reduced blood flow? But this ‘overactive hypothalamus’ would mean that the brain and whole body would overreact to every input or stimulus, whether from inside the body itself or from outside. For example, your stamina would be low, because after walking for 5 minutes the brain would react as if you’d run a marathon! And in the same way, having difficulties with loud noise, adjusting to changes in temperature, or with the immune system, getting very ill with every bug that goes around.

The hypothalamus, tiny as it is, is central to the proper function and regulation of four vital areas:
1. the whole central nervous system, including the brain and the autonomic system, and response to pain;
2. the whole metabolic system, how every hormone is regulated throughout the body, and your energy levels and response to stress;
3. the immune system, responding to short term or long term infections - the body may become more sensitive to new infections or to previous or latent infections or vaccinations, which may then become active, but at the same time the immune system might become too weak to fight them, - as well as allergies; and
4. the psychological ‘system’ and basic strong emotions through the limbic system and amygdala, like fear and anxiety, happiness and pleasure, compulsive behaviour, and guilt, and through the hippocampus, how these feelings can be tied in with long term memories and previous “life experiences”.

So, as you can see, if the hypothalamus does go wrong, and the pituitary and adrenals with it, then it really can have a devastating effect on pretty much everything that’s going on in your body! The sorts of things that seem to go wrong when people have ME.

I’ll put all of these ideas together in part 3. Even if there isn’t a cure yet, the better we might be able to understand ME, then the better we might be able to deal with it or possibly even help to treat it. See you again soon!