Neuron Replacement using Stem Cells

In a recent study, scientists created brain cells (neurons) from stem cells and implanted them into the brains of ten rats who had had strokes artificially induced by the researchers. The stem cells restored some of the rats ability to move. This was the first study showing that implanting neural stem cells in the brain could be done without causing cancer. From Standford's website, it says that someone has a stroke every 45 seconds in America, for a total of 700,000 strokes a year. That is an astounding number. The magnitude of suffering that is the result of these strokes is incalculable. Many people can die from having a stroke, but others are left with incapacitating disabilities. This can be especially difficult for loved ones who have to take care of the stroke victim. The researchers from Stanford think that human trials with stem cells for stroke patients may start as soon as 5 years from now.

Stem cells may also be used for several other conditions in the future. Patients with schizophrenia often show significant losses of gray matter in their brains. The reduction in brain matter can be up to 25% in specific areas. These losses are associated with many schizophrenic symptoms like paranoia, hallucinations, apathy and anhedonia. Other conditions such as depression and bipolar disorder are also associated with reduced brain volume in key areas associated with cognition and mood such as the hippocampus. In the future scientists may be able to implant stem cells directly into patient's brains to improve mental illness. Contrary to past dogma, scientists have discovered that the brain is continually creating new neurons (neurogenesis) in the hippocampus, an area of the brain critical for long term memory. Depression has been associated with reduced neurogenesis in the hippocampus and antidepressant drugs have the ability to increase neurogenesis. Using the new Deep TMS may allow researchers to selectively target the hippocampus with electrical stimulation so as to increase the brain's natural mechanism of generating new neurons. With a more sophisticated understanding of the brain, scientists may be able to achieve neurogenesis in brain areas not normally associated with new neuron growth. Or they may be able to guide the migration of neurons created in the hippocampus to other brain areas that are damaged or in need of repair.

Several researchers have already devised a technique to guide the position of neurons in the brain. They have incorporated iron particles into single neurons created from stem cells. Using targeted magnetic pulses, they may be able to precisely position these newly created neurons to specific brain areas to help ameliorate several conditions. So science will most likely progress to a better and more controlled creation of new neurons and the precise placement of those neurons into the requisite brain areas. For extreme life extension, replacing aging neurons may be necessary from time to time. In the future we may be able to use these techniques to periodically replace dying neurons with new ones. Intelligence enhancement is another area that stem cells may have some value in the future. Scientists may be able to increase the amount of neurons in an individual's brain in areas that are associated with certain performance tasks, such as memory, general intelligence and attention. Overall, these are exciting developments that could improve many currently devastating health conditions and potentially enhance normal people's functioning as well.