Leukocyte telomere length is not shortened in methamphetamine dependence or methamphetamine-induced psychosis but is increased following traumatic events

Methamphetamine use shortens telomere length in male adults and rats

BACKGROUND

Methamphetamine (MA) use increases the risk of age-related diseases. However, it remains uncertain whether MA use exhibits accelerated biological aging, as indicated by telomere length (TL), a proposed marker of aging. Here we conducted studies in both humans and rats to investigate the association between MA use and TL.

METHODS

We recruited 125 male MA users and 66 healthy controls, aged 30-40 years. MA users were diagnosed using DSM-5 criteria and categorized into two groups: non-severe (n = 78) and severe (n = 47) MA use disorder (MUD). MA-treated conditioned place preference (CPP) rats were utilized to validate our clinical investigations. TL was assessed using real-time polymerase chain reaction.

RESULTS

At clinical levels, MA users exhibited significantly shorter leukocyte TL compared to healthy controls. Among MA users, individuals with severe MUD had significantly shorter leukocyte TL than those with non-severe MUD. Importantly, both univariate and multivariate linear regression analyses demonstrated a negative association between the severity of MA use and leukocyte TL. In a rat model of MA-induced CPP, leukocyte TL was also significantly shortened after MA administration, especially in rats with higher CPP expression or reinstatement scores.

CONCLUSION

MA use shortened TL, and the severity of MA use was negatively correlated with TL. These findings provide new insights into the pathophysiology of accelerated aging caused by MA use and may have implications for identifying biomarkers and developing novel treatment strategies for MUD.

Psychological and biological mechanisms linking trauma with cardiovascular disease risk

Cardiovascular disease (CVD) is the leading cause of death and disability worldwide, and experiences of psychological trauma have been associated with subsequent CVD onset. Identifying key pathways connecting trauma with CVD has the potential to inform more targeted screening and intervention efforts to offset elevated cardiovascular risk. In this narrative review, we summarize the evidence for key psychological and biological mechanisms linking experiences of trauma with CVD risk. Additionally, we describe various methodologies for measuring these mechanisms in an effort to inform future research related to potential pathways. With regard to mechanisms involving posttraumatic psychopathology, the vast majority of research on psychological distress after trauma and CVD has focused on posttraumatic stress disorder (PTSD), even though posttraumatic psychopathology can manifest in other ways as well. Substantial evidence suggests that PTSD predicts the onset of a range of cardiovascular outcomes in trauma-exposed men and women, yet more research is needed to better understand posttraumatic psychopathology more comprehensively and how it may relate to CVD. Further, dysregulation of numerous biological systems may occur after trauma and in the presence of posttraumatic psychopathology; these processes of immune system dysregulation and elevated inflammation, oxidative stress, mitochondrial dysfunction, renin-angiotensin system dysregulation, and accelerated biological aging may all contribute to subsequent cardiovascular risk, although more research on these pathways in the context of traumatic stress is needed. Given that many of these mechanisms are closely intertwined, future research using a systems biology approach may prove fruitful for elucidating how processes unfold to contribute to CVD after trauma.