Methamphetamine, one of the most addictive and destructive drugs, causes chemical and molecular changes in the brain. Also known as meth, crank or chalk, it is classified as a Schedule II drug, alongside cocaine.
Experts treat meth addiction as a chronic relapsing psychiatric disorder that leads to severe health implications. They also say that at least half of a person’s susceptibility to drug addiction is linked to genetic factors. A study at the Boston University School of Medicine (BUSM) in 2015 demonstrated for the first time the significance of genes that influence susceptibility to substance abuse and other neuropsychiatric disorders.
The study, published in the journal PLOS Genetics, identified a gene that is associated with behavioral stimulant response to the drug methamphetamine. Known as heterogeneous nuclear ribonucleoprotein H1 (Hnrnph1), the gene has never been found to implicate behavioral effects of psychostimulants such as amphetamines or cocaine, in the past studies.
For the purpose of the study, researchers used an experimental model to identify the part of chromosome that was associated with differences in sensitivity to the stimulant properties of methamphetamine. Using “fine mapping” and “genome editing,” the researchers targeted each gene responsible for a noticeable behavioral response to the drug. To see how genes affect addiction, researchers identified Hnrnph1 codes for an RNA binding protein that regulates the processing of hundreds of other genes in the brain. “It’s certainly possible to say that there is a genetic component to addiction, with the top priority being to identify the direct genetic targets of Hnrnph1 within the reward circuitry,” the study notes.
“A better understanding of the brain region and cell type-specific binding targets of Hnrnph1 will tell us more about the function of this gene and possibly identify new therapeutic strategies for minimizing risk and treating psychostimulant addiction – a disorder for which there is currently no FDA-approved drug,” says Camron Bryant, Ph.D., assistant professor of Pharmacology and Experimental Therapeutics & Psychiatry at BUSM.
And most importantly, these findings may have relevance to other neuropsychiatric disorders, such as ADHD, schizophrenia and bipolar disorder, which involve dopaminergic dysfunction, and can also have implications for other neurodegenerative disorders including Parkinson’s and Huntington’s disease.
Methamphetamine is taken by snorting, smoking or injecting. Commonly used as a club drug, meth raises the energy level and causes a subsequent feeling of euphoria by producing copious amounts of neurotransmitter dopamine in the brain. When meth is ingested, the user feels more energetic, does not sleep for long periods, usually several days and loses his or her appetite. With a repeated use, the user develops tolerance to its pleasurable effects, which leads to further abuse. In addition to being addicted to methamphetamine, abusers may experience longer lasting and more harmful effects on their central nervous system, with symptoms such as significant anxiety, confusion, insomnia, mood disturbances and violent behavior.
According to a 2015 report by the National Institute on Drug Abuse (NIDA), illicit drug use in the U.S. has been consistently increasing. In a survey in 2013, an estimated 24.6 million Americans aged 12 or older (9.4 percent of the population) were found to use an illicit drug in a month prior to the study. Most people use drugs for the first time in their teens. There were just over 2.8 million new users of illicit drugs in 2013, or about 7,800 new users per day.
A habitual meth use may produce noticeable behavioral or personality changes, including irritability, restlessness and anxiety. The body of an addict builds a tolerance to the increased levels of the drug, causing long-term changes in the brain’s reward system. Meth dependence can have far-reaching impacts, affecting almost every organ in the human body. It may interfere with an individual’s ability to make decisions and can lead to frequent cravings. This is when a person needs professional help to get rid of this devastating habit and lead a normal life.
If you or your loved one needs treatment for addiction, it is time to seek help. You may reach out to the 247 Recovery Helpline to get the expert guidance on recovery and rehabilitation. Call our helpline number at 855-441-4405 or chat online for further information.