Washington May 28 : By carrying out the first large-scale analysis of proteins in the brains of monkeys addicted to cocaine, a research team led by an Indian boffin has revealed new information on how long-term cocaine use changes the amount and activity of various proteins affecting brain function.
According to Scott E. Hemby, Ph.D. of Wake Forest University School of Medicine, senior author of the study, the identified changes are more numerous and long-lasting than previously thought, which may provide a biological explanation for why cocaine addiction is so difficult to overcome.
Results from the study detail the effect of long-term cocaine intake on the amount and activity of thousands of proteins in monkeys.
For the study, the researchers used state-of-the-art 'proteomic' technology, which enables the simultaneous analysis of thousands of proteins, to compare the 'proteome' (all proteins expressed at a given time) between a group of monkeys that self-administered cocaine and a group that did not receive the drug.
Hemby said that the study provides a comprehensive assessment of biochemical changes occurring in the cocaine addicted brain.
"The changes we identified are profound and affect the structure, metabolism and signaling of neurons. It is unlikely that these types of changes are easily reversible after drug use is discontinued, which may explain why relapse occurs," said lead author Nilesh Tannu, M.D.
Hemby said that the development of medications to treat addictive disorders is guided in large part by our understanding of the brain mechanisms that produce the euphoric effects of the drugs.
It is equally important to understand the damage that long-term drug use causes to brain cells so that medications can be developed to reverse those effects and restore normal cell function in the brain.
The changes identified in the study point to significant and likely long-lasting damage to brain cells as a result of cocaine abuse.
"The duration of use and the amount of drug consumed that lead to such damage is currently not known, but is critical for understanding the long-term health consequences of cocaine abuse and determining the necessary modes of treatment," Hemby said.
"We hope that the information generated from the study will also serve an educational purpose as a deterrent to cocaine use," he added.
The study is published online in the journal Molecular Psychiatry.