Blood Pressure Medication and Myelin Repair in Multiple Sclerosis
April 11, 2015
We have received several inquiries about a recent report of a blood pressure medication that helps with myelin repair. This study was reported in Nature Communications: “Pharmaceutical integrated stress response enhancement protects oligodendrocytes and provides a potential multiple sclerosis therapeutic.”
This article received widespread media coverage because it involved a blood pressure medication that is already on the market.
This study used mouse oligodendrocyte precursor cells (OPC), the cells that eventually for myelin. These cells were grown on petri plates in the laboratory. These cells were grown in the presence of the blood pressure medication guanabenz (Wytensin). There was no difference in survival of cells grown with or without guanabenz. However, if interferon gamma (a chemical that promotes inflammation) is given to the cells, there is a decrease in cell survival by 22.5%. Giving guanabenz reverses this effect of interferon gamma. In a second experiment, slices of mouse brain were grown in petri dishes. OPCs were able to remyelinate these brain slices. If interferon gamma was given, the remyelination was markedly decreased. If both interferon gamma and guanabenz were given the remyelination was restored. In a third study, mice were engineered to have much higher levels of interferon gamma than normal. These mice had less myelin than normal, but this was improved by giving guanabenz. Finally, mice given EAE had less severe EAE than control mice.
These studies indicate that the effects of guanabenz are directed at blocking the effects of interferon gamma. Interferon gamma is known to worsen MS activity. However, these studies were all conducted in mice and the effects of guanabenz in human MS are not known. Furthermore, many of our existing MS medications already decrease the effects of interferon gamma, so it is unknown if guanabenz offers any benefits different from these known MS treatments. These results do not apply to other blood pressure medications. For now, it is important for people with high blood pressure and MS to have their high blood pressure treated with the most appropriate medication for their blood pressure. There are not any preferred blood pressure medications specifically for those with MS. Further studies will be needed before we can determine whether guanabenz is useful for the treatment of MS.