In a study at the University of Rochester Medical Center, neuroscientists found that statins, among the most prescribed drugs, affect brain cells in the lab. They looked at glial progenitor cells, stem-like cells that keep the brain healthy because they are the main source of other cells the brain needs, and found that statins push these cells to turn into one particular cell type.
Several studies have suggested that statins may help prevent dementia, but they weren't conclusive. The new study, published in the journal Glia by Professor Steven Goldman, showed an effect of statins on human brain cells in culture. The experiments used cells taken from human brains and exposed to doses of statins like those patients take; the study was not done in people.
Goldman and colleague Fraser Sim identified the molecular signals that guide the development of these progenitor cells, using a genetic screen to find the genes most active in them compared with other brain cells. Many were linked with cholesterol, including the enzyme HMG-CoA reductase, a key enzyme in making cholesterol and the target of statins. It was surprising that cholesterol pathways were so active in these cells, pathways that millions of people block with treatment every day.
The team then tested the two most used statins, simvastatin and pravastatin, on glial progenitor cells, which can become either astrocytes or oligodendrocytes. The cells came from 16 patients whose brain tissue was removed during surgery for epilepsy, tumours or blood vessel problems. Both drugs pushed the progenitor cells to become oligodendrocytes, at doses like those patients take: in one experiment with pravastatin, there were more than five times as many oligodendrocytes as in untreated cultures.
Doctors see statins as a possible treatment for multiple sclerosis, in which the myelin that coats nerve fibres in the brain and spinal cord is destroyed. Myelin is made by oligodendrocytes, so making more of them could help repair the damage seen in MS.
On the other hand, the body keeps a reserve of these cells to repair damage from infection, bleeding, a blow to the head or brain inflammation. "These cells are ready to respond if an area of the brain is damaged by injury or a stroke," says Sim. "So what happens if they run out too early?" Progenitor cells make up about 3% of brain cells.
The research may also be relevant to diabetes drugs: a signalling molecule called PPAR gamma was involved in the statins' effect, and it is the target of the diabetes drugs Avandia and Actos, which may have a similar effect.
The authors suggest that the possible long-term effects of statins on the brain's reserve of progenitor cells deserve study. These are lab results: people taking statins should not stop them without talking to their doctor.
Like
Love
Angry
Dislike
