I hate the cold. It triggers my bladder and stiffens my legs. When the leaves start to turn in Maryland, I start thinking about the palm trees in Florida.
So, I was interested to read research from the University of Geneva that indicates that exposure to cold may stop, and even reverse, nerve demyelination that occurs in multiple sclerosis (MS).
These scientists applied the concept of life history theory to the overactivation of the immune system in autoimmune diseases such as MS. This theory suggests that an organism normally uses its internal resources for growth and reproduction, but when its environment becomes hostile, those resources are diverted to saving energy and repelling the external threat. The external threat in this study was cold.
MS symptoms improve in cold mice
In the study, researchers infected mice with a type of brain inflammation that mimics how MS affects the immune system. Then they put the mice into a colder than normal living environment to see how their bodies redirected resources to fight the cold. Mice generally like temperatures between 30 and 32 C (86-90 F). These mice had their environment lowered to 10 C (50 F). The researchers found that not only did the mice divert resources to help maintain their overall body heat, the heat was taken from the immune system. Once that happened, the immune system decreased its attack on the nervous system, and the MS symptoms improved.
“The animals did not have any difficulty in maintaining their body temperature at a normal level, but, singularly, the symptoms of locomotor impairments dramatically decreased, from not being able to walk on their hind paws to only a slight paralysis of the tail,” study co-author Doron Merkler, a professor at the university’s pathology and immunology department, noted in a press release.
The researchers believe the symptoms in the mice decreased because the cold modulated the activity of monocytes, which are white blood cells that regulate inflammation. By forcing the body to increase its metabolism to maintain body heat, the cold diverted resources away from the immune system. This led to a decrease in harmful immune cells and, therefore, a decrease in symptoms.
To me, a nonscientist, this seems like the way my legs weaken in the summer heat but quickly improve when I jump into a cool swimming pool.
It’s just a mouse model
I’m always reluctant to put too much stock into what mice have to say. Yet this is an interesting concept, and the University of Geneva scientists hope to expand their cold research so that it can be applied in the clinic.
Meanwhile, I’m getting ready to head to Florida soon, where I can find the heat I love and I know I can always find a nearby swimming pool for relief of my MS symptoms.
(This post first appeared as my column on the MS News Today website.)
(Featured image by Ina Hoekstra from Pixabay.)
