Since scientists don't know what causes MS or exactly how it works its damage, that hampers attempts to cure it. I came across a couple intriguing perspectives on the genesis of MS that I thought other people might be interested in.
First is an article described by MSNews from the Accelerated Cure Project as giving "an interesting alternate theory for MS as a vascular disease (1).
I don’t completely understand this, but apparently the researchers did a procedure called venography on people with and without MS. According to Wikipedia, venography (or phlebography) is “a procedure in which an x-ray of the veins, a venogram, is taken after a special dye is injected into the bone marrow or veins” (2).
Unlike the controls (normal people or people with other neurological conditions), people with MS had “multiple severe extracranial stenosis, affecting the principal cerebrospinal venous segments” (3), which I think means that they had narrowing of the veins (and I guess the blood flow) outside the cranium but near the brain and spine. The were looking at venous outflow, which presumably would affect the outflow of blood.
Apparently, there were four different patterns of venous problems (which might go with the four clinical types or maybe with the four pathological types of MS?). The patterns generally associated with RRMS/SPMS and PPMS were different.
These patterns of problems are “characterised by multiple substitute circles [alternative pathways or vicarious venous shunts (this second seems to mean that the blood moves through an abnormal passageway) that allow for the piping of blood toward available venous segments outside the CNS], with a very high incidence of reflux in both intracranial and extracranial venous segments, and loss of the postural regulation of cerebral venous outflow.” The researchers think this reflux is likely caused by a “stenosing lesion that cannot be crossed with postural or respiratory mechanisms, thereby becoming a long-lasting reverse flow” (3). (that reflux/reverse flow bit doesn’t sound too good, does it?)
Intriguingly, the authors suggest that “the absence of Doppler and venographic features [whatever those are] of CCSVI [chronic cerebrospinal venous insufficiency] in controls suggests that venous obstructions may be causative of MS rather than a coincidental finding” (3). However, they do also entertain the opposite hypothesis, i.e., that the vascular abnormalities are caused by MS, although they then point out what they see as evidence that this explanation is less likely. In any event, more research is needed.
Secondly, I came across an article that talked about the inadequacy of EAE (experimental allergic encephalomyelitis) as an animal model of MS (4). EAE is induced in mice and causes demyelination, lesions, and relapses and remissions. However, from what I can tell, researchers are pretty good at curing EAE, but obviously this hasn’t carried over to curing MS. This suggests that there are significant differences between EAE and MS. These researchers think that EAE is more similar to ADEM [acute disseminated encephalomyelitis], that “both EAE and ADEM are T-cell-dependent, organ-specific, autoimmune diseases of the central nervous system,” (4) and that EAE should not be used as a justification for an inflammatory, autoimmune theory of MS. They say that MS is different from EAE because MS arises naturally, includes “progressive and global brain and spinal cord atrophy” from an early stage, and involves the normal-appearing white matter, whereas EAE has to be externally induced and does not share these other characteristics. EAE is also more typically monophasic or requires repeat “challenges to some encephalitogenic antigen” to induce relapses, which has not been shown to be necessary in MS.
They list some other differences and then baldly state that “nearly 60 years of EAE-based research yielded not a single MS-halting therapy.” They also point out that it is now believed that it is neurodegeneration rather than demyelination that causes long-term disability. They suggest, among other things, that a new animal model for MS is needed.
Interesting, in a third article, researchers report having found what they hope to be just such a model. Researchers at the Max Planck Institute of Neurobiology have bred mice that “spontaneously develop a disease pattern that is practically identical to the course of the human form of MS most common in our part of the world [RRMS??]. Because the disease also develops spontaneously in humans, the new model is superior to all of the previous models which only develop MS symptoms following injection with brain tissue. Moreover, the research using the new model has already prompted a rather sensational discovery: the emergence of the disease requires significantly more immune cells than previously assumed” (5).
The common wisdom seems to be that MS is mainly caused by misguided T cells (a type of immune cell). This new model suggests that another type of immune cell, B cells, have an essential role and that if the B cells are not also triggered, the disease will not start. Also, in MS some errant T cells are more aggressive than others and the researchers found that some of these will attack more than one protein (which was apparently unexpected). The researchers think that targeting these super-activated T cells could be a productive treatment strategy.
Sorry, this post got really long, but I hope a few of you find this sort of thing as fascinating as I do.
1. Chronic cerebrospinal venous insufficiency in patients with MS, http://www.acceleratedcure.org:8080/node/3532
2. Venography, http://en.wikipedia.org/wiki/Venography
3. Zamboni, P. et al. “Chronic cerebrospinal venous insufficiency in patients with multiple sclerosis.” J Neurol Neurosurg Psychiatry. 2009 April; 80(4): 392–399. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=19060024
4. Chaudhuri, Abhijit and, Peter O Behan. “Multiple sclerosis and EAE - are researchers barking up the wrong tree?” http://www.msrc.co.uk/index.cfm?fuseaction=show&pageid=7
5. Tracking Down The Causes Of Multiple Sclerosis - New Discoveries In Immune Response, http://www.medicalnewstoday.com/articles/153740.php