Understanding the Mechanisms of Action and Effects of Drugs of Abuse

The epigenetically regulated PP1α expression by KDM1A may contribute to oxycodone conditioned place preference in mice

The lysine-specific demethylase 1 (KDM1A) is reported to be a regulator in learning and memory. However, the effect of KDM1A in oxycodone rewarding memory has yet to be studied. In our study, rewarding memory was assessed by using conditioned place preference (CPP) in male mice. Next generation sequencing and chromatin immunoprecipitation-PCR were used to explore the molecular mechanisms. Oxycodone significantly decreased PP1α mRNA and protein levels in hippocampal neurons. Oxycodone significantly increased KDM1A and H3K4me1 levels, while significantly decreased H3K4me2 levels in a time- and dose-dependent manner. Behavioral data demonstrated that intraperitoneal injection of ORY-1001 (KDM1A inhibitor) or intra-hippocampal injection of KDM1A siRNA/shRNA blocked the acquisition and expression of oxycodone CPP and facilitated the extinction of oxycodone CPP. The decrease of PP1α was markedly blocked by the injection of ORY-1001 or KDM1A siRNA/shRNA. Oxycodone-induced enhanced binding of CoRest with KDM1A and binding of CoRest with the PP1α promoter was blocked by ORY-1001. The level of H3K4me2 demethylation was also decreased by the treatment. The results suggest that oxycodone-induced upregulation of KDM1A via demethylation of H3K4me2 promotes the binding of CoRest with the PP1α promoter, and the subsequent decrease in PP1α expression in hippocampal neurons may contribute to oxycodone reward.

Substance Addiction Rehabilitation Drugs

The relapse rate of substance abusers is high, and addiction rehabilitation adjunct drugs need to be developed urgently. There have been numerous reports on blocking the formation of substance addiction, but studies on drugs that can alleviate withdrawal symptoms are very limited. Both the dopamine transporter (DAT) hypothesis and D3 dopamine receptor (D3R) hypothesis are proposed. DAT activators reduce the extracellular dopamine level, and D3R antagonists reduce the neuron's sensitivity to dopamine, both of which may exacerbate the withdrawal symptoms subsequently. The D3R partial agonist SK608 has biased signaling properties via the G-protein-dependent pathway but did not induce D3R desensitization and, thus, may be a promising drug for the withdrawal symptoms. Drugs for serotoninergic neurons or GABAergic neurons and anti-inflammatory drugs may have auxiliary effects to addiction treatments. Drugs that promote structural synaptic plasticity are also discussed.

Women, Addictions, Mental Health, Dishonesty, and Crime Stigma: Solutions to Reduce the Social Harms of Stigma

British drug policies could underserve women with treatment needs, and this paper provides evidence that communication through the words and actions of professionals across drug and alcohol services, health and mental health, social work and the criminal justice sector can leave women feeling stigmatised and failed. Women live with the stigma of 'the lying addict'; however, documents and courtroom statements provided by professionals can misrepresent women's experiences, which exacerbates social harm. Data are drawn from feminist participatory action research, where female lived experience experts worked alongside academics to implement a qualitative study using interviews and focus groups with women using treatment services (n = 28) and an online world café with professionals working with these women (n = 9) and further professionals providing support at lived experience data collection events (n = 5). This data set is cross-referenced with one-to-one and small-group interviews with professionals in the field (n = 17) conducted by a third-sector partner. Findings establish that stigma negatively impacts the identification of treatment needs and access to timely and appropriate service delivery. Social harms to women with addictions could be significantly reduced with timely, authentic, honest, gender-informed and trauma-informed practices for girls and women using drugs and alcohol to self-medicate from traumatic experiences.