Synaptic Neurotransmission Depression in Ventral Tegmental Dopamine Neurons and Cannabinoid-Associated Addictive Learning

Drug addiction is an association of compulsive drug use with long-term associative learning/memory. Multiple forms of learning/memory are primarily subserved by activity- or experience-dependent synaptic long-term potentiation (LTP) and long-term depression (LTD). Recent studies suggest LTP expression in locally activated glutamate synapses onto dopamine neurons (local Glu-DA synapses) of the midbrain ventral tegmental area (VTA) following a single or chronic exposure to many drugs of abuse, whereas a single exposure to cannabinoid did not significantly affect synaptic plasticity at these synapses. It is unknown whether chronic exposure of cannabis (marijuana or cannabinoids), the most commonly used illicit drug worldwide, induce LTP or LTD at these synapses. More importantly, whether such alterations in VTA synaptic plasticity causatively contribute to drug addictive behavior has not previously been addressed. Here we show in rats that chronic cannabinoid exposure activates VTA cannabinoid CB1 receptors to induce transient neurotransmission depression at VTA local Glu-DA synapses through activation of NMDA receptors and subsequent endocytosis of AMPA receptor GluR2 subunits. A GluR2-derived peptide blocks cannabinoid-induced VTA synaptic depression and conditioned place preference, i.e., learning to associate drug exposure with environmental cues. These data not only provide the first evidence, to our knowledge, that NMDA receptor-dependent synaptic depression at VTA dopamine circuitry requires GluR2 endocytosis, but also suggest an essential contribution of such synaptic depression to cannabinoid-associated addictive learning, in addition to pointing to novel pharmacological strategies for the treatment of cannabis addiction

The influence of venous thromboembolism on quality of life and severity of chronic venous disease.

BACKGROUND: It is not known whether burden-of-illness differs in chronic venous disease patients with prior venous thromboembolism compared with patients with other forms of chronic venous disease. OBJECTIVE: To compare severity of disease and quality of life in chronic venous disease patients with and without prior venous thromboembolism. PATIENTS AND METHODS: The VEINES Study population is an international cohort of 1531 outpatients with chronic venous disease in Belgium, France, Italy and Canada. Clinical severity of chronic venous disease graded using the seven-category 'CEAP' scale, and quality of life using standardized generic (SF-36) and venous disease-specific (VEINES-QOL/Sym) questionnaires were compared in patients with and without venous thromboembolism. Multivariable analyses with adjustment for known confounders were used to examine associations between venous thromboembolism and quality of life. RESULTS: One hundred and fifty-one (10%) patients had prior venous thromboembolism. These patients had more severe chronic venous disease than those without venous thromboembolism (P <0.0001), including a higher frequency of healed or active ulcers (29% vs. 7%, respectively). Multivariable analyses controlling for age, sex, country, education, body mass index, years of chronic venous disease and comorbid conditions demonstrated that prior venous thromboembolism was an independent predictor of poorer generic quality of life (SF-36 Mental Component Summary score, P=0.047; SF-36 Physical Component Summary score, P=0.012) and venous disease-specific quality of life (VEINES-QOL, P = 0.0002; VEINES-Sym, P=0.009). CONCLUSIONS: Disease severity is worse and quality of life poorer in chronic venous disease patients with prior venous thromboembolism compared with patients with other forms of chronic venous disease. Our findings support the need for further research of interventions to prevent and treat the long-term complications of venous thromboembolism

From long-term follow-up Recommendations for clinical practice to plain language summaries for childhood, adolescent, and young adult cancer survivors

\ua9 2024 The AuthorsBackground: Having sufficient knowledge of cancer diagnosis, treatment and late effects in survivors of childhood, adolescent, and young adult (CAYA) cancer is important for effective self-management and optimising health outcomes. Therefore, in collaboration with different stakeholders, the PanCare PLAIN Information Group converted the PanCareFollowUp Recommendations for late effects surveillance into information summaries that are Person-centred, written in Lay language, Accessible, Internationally relevant, and Navigable (PLAIN). Methods: The PanCare PLAIN Information Group, comprising 21 stakeholders from seven European countries, collaborated to provide concise information for survivors and their families. The aim was to deliver PLAIN summaries that are clear and accessible for the majority of survivors, while providing links to additional sources of information. The PLAIN summaries were drafted by the PanCare PLAIN Information Group and subjected to two internal and one external consultation round, the latter involving experts, CAYA cancer survivors and parents/caregivers. Results: In total, 45 PLAIN summaries were developed, each corresponding to one of the PanCareFollowUp Recommendations for late effects surveillance. The summaries provide information about late effects, personal health risks, important symptoms and signs, recommended surveillance strategies, possible referral and treatment options, and self-care. Conclusions: The PLAIN summaries are meant to increase knowledge in survivors and their families, while they may also inform healthcare professionals. Along with their translations, the PLAIN summaries will be made freely available on the PanCare website, with a link provided on the European Network of Youth Cancer Survivors information platform. In addition, they will become and integral part of the Survivorship Passport

Is a 'general' theory of addiction possible? A commentary on: a multistep general theory of transition to addiction

[No abstract available