I say to many of patients one of the most powerful predictors of progressive, or more correctly worsening, MS is ageing. Age also predicts recovery of function; the younger you are the better you do. This study shows that ageing restricts the ability of stem cells to make oligodendrocytes to promote remyelination.
As you are aware age also predicts response, or lack or response, to DMTs. The older you are the less effective DMTs are. The list linked to ageing and poor prognosis goes on ….
I have always said ‘life is a sexually transmitted neurodegenerative disease with a 100% mortality’. This usually gets a mutated laugh until people start pondering the joke and its implications and then gradually realise that I am being serious.
Evolution never designed, and selected, the human brain and nervous system to function much past the age of 35. It is only relatively recently that life expectancy has increased dramatically with the requirement of our brains to function into ‘old age’. It is clear that when we measure cognitive function, and brain volume, it is all downhill from about 35 years of age.
Those of us who are older than 35 notice the subtle cognitive impairments that increase with age and the gradual malfunction and deterioration in our nervous systems. When last have you tried tight-rope walking? Your failing balance system is simply a reflection of the global rot that is also shredding your cognition. Fortunately, we have enough reserve to adapt and cope with the slow decline in our mental faculties. However, if we live long enough we are all likely to become demented. Dementia in this setting is simply the reduction of cognition to a point when you can’t manage socially and occupationally. To prevent the inevitable consequence of ageing is there anything we can do to optimise our brain health so our ‘brains outlive’ our ‘bodies’?
There is a lot we can do to improve brain health. However, some of the interventions may require the administration of medications in the future. For the anti-ageing revolution to happen, and be adopted by society, we need to make ageing a disease.
By defining ageing as a disease it changes everything. Firstly, it creates incentives for the pharmaceutical industry to invest in the necessary R&D to get drugs to market. If ageing is a disease healthcare providers will pay for interventions. The corollary is that if ageing is not defined as a disease, any interventions to delay or modify ageing, will be limited to lifestyle interventions. By defining ageing as a disease it will allow us to develop tools for population screening to identify people who are either healthy or in the presymptomatic phase of known neurodegenerative disease. This will then allow us to test preventive strategies to delay the onset of symptomatic disease.
If on the other hand, you have MS we already know you have a neurodegenerative disease that shreds reserve capacity and brings forward ageing mechanisms, which is why we need to manage MS as early and as effectively as possible and holistically. This is why the new treatment target is ‘to maximise brain health for the lifetime of the person with MS’.
Please be aware that ageing is a biological process and hence we can target the biology with both lifestyle interventions and drugs. For example, recent evidence suggests metformin, a diabetes drug, may reverse some of the ageing programmes. Dimethyl fumarate (DMF), a licensed MS DMT, seems to activate antiageing pathways that overlap with pathways linked to specific dietary interventions, i.e. calorie-restricted, intermittent fasting and ketogenic diets. Should all MSers be on metformin and/or DMF and/or one of these diets? We need trials to test these hypotheses. But at least there are investigators exploring the questions.
Please let me know if you find the anti-ageing hypothesis of MS compelling; it overlaps with diet, sleep, exercise and many other things that I can discuss in future blog posts.
Rivera et al. Aging restricts the ability of mesenchymal stem cells to promote the generation of oligodendrocytes during remyelination. Glia. 2019 Apr 30. doi: 10.1002/glia.23624.
Multiple sclerosis (MS) is a demyelinating disease of the central nervous system (CNS) that leads to severe neurological deficits. Due to their immunomodulatory and neuroprotective activities and their ability to promote the generation of oligodendrocytes, mesenchymal stem cells (MSCs) are currently being developed for autologous cell therapy in MS. As aging reduces the regenerative capacity of all tissues, it is of relevance to investigate whether MSCs retain their pro-oligodendrogenic activity with increasing age. We demonstrate that MSCs derived from aged rats have a reduced capacity to induce oligodendrocyte differentiation of adult CNS stem/progenitor cells. Aging also abolished the ability of MSCs to enhance the generation of myelin-like sheaths in demyelinated cerebellar slice cultures. Finally, in a rat model for CNS demyelination, aging suppressed the capability of systemically transplanted MSCs to boost oligodendrocyte progenitor cell (OPC) differentiation during remyelination. Thus, aging restricts the ability of MSCs to support the generation of oligodendrocytes and consequently inhibits their capacity to enhance the generation of myelin-like sheaths. These findings may impact on the design of therapies using autologous MSCs in older MS patients.