A drug widely used to treat cancer may cause brain damage, with the effects lasting for years after the end of treatment, research suggests.
The drug, 5-fluorouracil (5-FU), is used, alongside others, to treat cancers of the breast, ovaries, colon, stomach, pancreas and bladder.
Tests on mice showed it destroys vital cells in the brain that help to keep nerves functioning properly.
The University of Rochester study features in the Journal of Biology.
The researchers say their findings could explain some of the neurological side effects associated with chemotherapy - a phenomenon often known as "chemo brain".
These include memory loss, poor concentration, and in more extreme cases, seizures, impaired vision and even dementia.
Until recently they were often dismissed as the by-products of fatigue, depression and anxiety related both to the diagnosis and treatment of cancer.
But many patients show symptoms: a previous study by the Rochester team found more than 80% of breast cancer patients reported some form of mental impairment after chemotherapy.
Protective sheath
The latest study found 5-FU attacks oligodendrocyte cells in the brain and the precursor stem cells from which they originate.
These cells play a crucial role in the central nervous system, producing myelin, the protective sheath that keeps nerve fibres in working order.
If myelin is not constantly renewed, communication between nerve cells is damaged.
The researchers showed that oligodendrocytes virtually disappeared from the brains of mice six months after the animals were treated with 5-FU.
Writer :
BBC
