Long-term heroin use was associated with the downregulation of systemic platelets, BDNF, and TGF-β1, and it contributed to the disruption of executive function in Taiwanese Han Chinese

- Long-term heroin used decreased blood platelets counts.
- The decrease of platelets subsequently downregulated the plasma brain-derived neurotrophic factor (BDNF) and transforming growth factor beta 1 (TGF-β1).
- The decrease of plasma BDNF may disrupt the executive function in heroin addicts.
- Platelet-protective agents might be a new focus for heroin addiction therapy.

BackgroundLong-term heroin addicts have low plasma brain-derived neurotrophic factor (BDNF) levels. However, the mechanisms and effects of systemic disturbances of BDNF caused by heroin remain unclear.ObjectiveBlood platelet might be a source of neurotrophic factors like BDNF and transforming growth factor (TGF)-β1. Thus, we investigated the effects of heroin on platelets, BDNF and TGF-β1, the association between blood platelets, BDNF, TGF-β1, and executive function in long-term heroin addicts.MethodsWe enrolled 170 heroin addicts and 141 healthy controls. We measured their plasma BDNF and TGF-β1 levels and counted their platelets, red and white blood cells. The Wisconsin Card Sorting Test (WCST) was used to assess their executive function.ResultsPlasma BDNF and TGF-β1 levels were significantly downregulated in long-term heroin addicts. BDNF, TGF-β1, and platelet levels were lower in patients who had used heroin for more than 6 years than in those who had used it for less than 6 years. Lower plasma BDNF and TGF-β1 levels were highly correlated with the changes in platelet counts. In the WCST, the number of trials needed to complete the first category were negatively associated with platelet counts and BDNF levels.ConclusionsIn long-term heroin addicts, lower platelet counts contributed to lower plasma BDNF and TGF-β1 levels, which, in turn, contributed to the disruption of executive function after long-term heroin use. Neurotrophic- and platelet-protective agents might provide a useful research focus for heroin addiction therapy.