The main thing is to start on time
A group of researchers from the University of California, Riverside, has shown the effectiveness of indazole chloride (an estrogen receptor ligand) in restoring vision in mice with multiple sclerosis.
The organ of vision includes the eyes, the optic nerve and brain structures responsible for receiving, transmitting and processing visual information. With multiple sclerosis, the immune system attacks myelin and "exposes" the nerves, often the optic nerve and other parts of the visual system suffer first.
As a result, approximately 50% of patients with multiple sclerosis have optic neuritis before the first symptoms of the disease appear. Almost all patients with multiple sclerosis suffer from visual impairment during the progression of the disease.
Symptoms may include eye pain, blurred vision, and progressive vision loss, which can lead to blindness.
The optic nerve is a richly myelinated bundle of nerve fibers extending from the back of the eye, which transmits information from the retina to the brain via electrical impulses. Myelin acts as an insulating substance, it accelerates the transmission of these electrical impulses. Partial loss of myelin slows down the transmission of visual information; significant loss of myelin can completely stop the signal.
The researchers used indazole chloride to treat demyelinated axons of the visual tract. The medicine contributed to the restoration of the myelin sheath, which led to a partial improvement in vision.
Previously, indazole chloride was shown in mice to reduce motor disorders, enhance myelination and neuroprotection of the spinal cord and corpus callosum. A new study has proved that the optic nerve and the visual tract, which undergo significant autoimmune inflammation, demyelination and damage, are able to restore some functions with the help of indazole chloride, which weakens inflammation and enhances remyelination.
The visual tract in mice is similar to that in humans, so the mouse brain is a convenient and informative model for studying visual impairments. The research team created a mouse model of multiple sclerosis, allowing the disease to progress for about 60 days, and when the disease peaked (on days 15-21), half of the mice were injected with indazole chloride. At the end of the experiment, functional tests were performed to measure the electrical potentials of the optic nerve and immunohistochemical studies to assess the condition of the visual tract. The mice injected with the drug showed an increase in myelination with an improvement in visual function by about 50%.
The mechanism of remyelination of the visual tract, triggered by indazole chloride, is still being studied.
The authors note that in the study, treatment of mice began at the peak of the disease, when the brain is severely affected and some of the axons that are potentially able to restore visual function were irreversibly damaged. Therefore, to improve vision, treatment should be started as early as possible in order to return 75-80% of the original visual function.
There is an urgent need for therapy that eliminates neurological disorders in patients with multiple sclerosis. Currently, drugs approved for the treatment of multiple sclerosis reduce inflammation, but do not prevent neurodegeneration and do not initiate remyelination.
Article by M.T.Sekyi et al. An allegation of extensive visual pathway dysfunction by a remyelinating drug in a chronic mouse model of multiple sclerosis is published in the journal Brain Pathology.
Aminat Adzhieva, portal "Eternal Youth" http://vechnayamolodost.ru based on UCR materials: Remyelinating drug could improve vision in patients with multiple sclerosis.