Scientists Discover Link Between Parkinson’s and Meth Addiction
The protein, known as organic cation transporter 3 (oct3) satisfies a long-term gap that scientists have dealt with in trying to understand the brain damage that causes symptoms such as tremors, stiffness, slowness of movement and postural instability. Doctors do know that symptoms of Parkinson’s are the result of the death of a very small, specialized group of brain cells. The challenge has been in understanding why those cells die.
Studies into this area have often ignored astrocytes, the type of cell that is the most common in the brain, as they do not send electrical signals. As a result, neurons got more of the attention, yet astrocytes still play a key role in Parkinson’s disease. When specific chemicals are released from atrocytes, such as dopamine, neurons are killed. When oct3 is present the impact of chemical reactions in the brain change.
Scientists determined that oct3 is used for helping astrocytes to soak up the excess dopamine in the space around the neurons. This process is greatly interrupted in the use of methamphetamine and other highly addictive drugs.
When dopamine isn’t removed as quickly or thoroughly as it normally is, people can feel euphoric while experiencing brain damage at the same time. As a result of these findings, scientists have determined that in those who have reduced Oct3 activity, there is a higher potential for addiction.
"How you choose to manipulate the function of oct3 depends on the source of the toxic molecules," said Kim Tieu, Ph.D., a corresponding author of the paper and assistant professor in the Department of Environmental Medicine at the University of Rochester Medical Center, in Science Daily.
“You would try to lessen its effects in a condition where it makes a toxic molecule available to vulnerable cells, as illustrated in the current model of Parkinson's disease. But in the case of drug addiction, you might try to increase it, to lessen the impact of a drug like methamphetamine."