COMMENTS: 8 weeks of exercise significantly increased D2 receptors in meth addicts undergoing treatment. This supports the following:
- Exercise can help reverse desensitization even in meth addicts.
- D2 receptor levels are not set in stone: environment matters.
- Meth use seems to cause a drop in D2 receptors. As with #2 this refutes the “you born to be an addict” meme.
Neuropsychopharmacology. 2015 Oct 27. doi: 10.1038/npp.2015.331.
Methamphetamine Use Disorder is associated with striatal dopaminergic deficits, which have been linked to poor treatment outcomes, identifying these deficits as an important therapeutic target. Exercise attenuates methamphetamine-induced neurochemical damage in the rat brain, and a preliminary observation suggests that exercise increases striatal D2/D3 receptor availability (measured as non-displaceable binding potential, BPND) in patients with Parkinson’s disease.
The goal of this study was to evaluate whether adding an exercise-training program to an inpatient behavioral intervention for methamphetamine use disorder reverses deficits in striatal D2/D3 receptors. Participants were adult men and women who met DSM-IV criteria for methamphetamine dependence and were enrolled in a residential facility, where they maintained abstinence from illicit drugs of abuse and received behavioral therapy for their addiction.
They were randomized to a group that received 1-hr supervised exercise training (n=10) or one that received equal-time health-education training (n=9), 3 days/week for 8 weeks.
They came to an academic research center for positron emission tomography (PET) using 18F-fallypride to determine the effects of the 8-week interventions on striatal D2/D3 receptor BPND.
At baseline, striatal D2/D3 BPND did not differ between groups. However, after 8-weeks, participants in the exercise group displayed a significant increase in striatal D2/D3 BPND, while those in the education group did not. There were no changes in D2/D3 BPND in extrastriatal regions in either group.
These findings suggest that structured exercise training can ameliorate striatal D2/D3 receptor deficits in methamphetamine users, and warrants further evaluation as an adjunctive treatment for stimulant dependence.Neuropsychopharmacology accepted article preview online, 27 October 2015. doi:10.1038/npp.2015.331.