Mutant Enzymes Help Break Cocaine Habit
Cocaine and Addiction
Although it is not as popular or its use as widespread as it once was, cocaine is still a commonly abused drug, and one that causes devastating addictions and health complications. It comes from the leaves of the coca plant, which is native to South America. The natives of that region have used the coca leaves for millennia, as both medicine and a way to get high. It was only with the modern ability to extract the cocaine from the leaves and purify it that the drug became a worldwide destructive force.
Cocaine is a white powder that is inhaled through the nose. This practice gives the user a very quick high because the drug goes right into the blood stream from the nasal passages. In the brain, cocaine blocks chemicals called neurotransmitters from being reabsorbed. This results in a flood of these chemicals in the brain, and the resulting high. Over time and with use, the high is more difficult to obtain. The user needs more and more to get high, and experiences withdrawal symptoms.
Cocaine Addiction Treatment
For most addicts who use cocaine, treatment involves going to rehab, attending a 12-step program, seeking counseling, or all of the above. Unlike heroin addicts or alcoholics, cocaine addicts have no options for medical treatment, but that is changing. In 2012, researchers began trials for treating cocaine addiction using a combination of drugs used with heroin and painkiller addicts.
The human trials are based on the success of using this combination on rats. Buprenorphine, which is an opioid, as is heroin, can be used to treat heroin addicts. However, in cocaine addicts, the buprenorphine itself can become an addictive substance. Researchers found that when used in combination with a drug called naltrexone, it reduced cocaine use in lab rats without creating a new addiction.
Now, even more exciting research has created a completely new substance that has the potential to be a real cure for cocaine addiction. Chinese researchers created a mutant version of an enzyme called butyrylcholinesterase, or BChE for short, which breaks cocaine down quickly. BChE normally breaks down cocaine in the body, but it does so very slowly, allowing a cocaine user to get the flood of brain chemicals going that produces a high.
The new mutant form was created by researchers using computer modeling. The enzyme they made in this way breaks down cocaine in the body 1,000 times faster than the natural BChE enzyme. After using computer models to design mutants of the enzyme, the researchers tested each one in the laboratory and the final product was the fastest at breaking down cocaine. This manner of designing, selecting, and then testing enzymes could lead to even more medical treatments for different types of addiction. The researchers also designed the mutant enzyme to be selective for cocaine. This means that it targets cocaine only and will not be used up in the body for breaking down any other compounds.
The researchers hope that their BChE mutant will be able to be taken by cocaine addicts as a medical treatment. The idea is that with the mutant enzyme, any cocaine ingested or snorted would be broken down too quickly to produce a high. Without a high, the cocaine addict would have no reason to use. Human trials for this revolutionary treatment have already begun and are showing promise.
As researchers make headway in understanding how drugs affect our brains and our bodies, better and more effective treatments will follow. The recent breakthroughs in cocaine addiction treatment hold great promise for those who are struggling with this disease. With the technology used to develop these treatments, there is even a possibility that researchers will find better medications for other addictive substances.