Role of Oxytocin and Vasopressin in Neuropsychiatric Disorders: Therapeutic Potential of Agonists and Antagonists

Oxytocin (OT) and vasopressin (AVP) are hypothalamic neuropeptides classically associated with their regulatory role in reproduction, water homeostasis, and social behaviors. Interestingly, this role has expanded in recent years and has positioned these neuropeptides as therapeutic targets for various neuropsychiatric diseases such as autism, addiction, schizophrenia, depression, and anxiety disorders. Due to the chemical-physical characteristics of these neuropeptides including short half-life, poor blood-brain barrier penetration, promiscuity for AVP and OT receptors (AVP-R, OT-R), novel ligands have been developed in recent decades. This review summarizes the role of OT and AVP in neuropsychiatric conditions, as well as the findings of different OT-R and AVP-R agonists and antagonists, used both at the preclinical and clinical level. Furthermore, we discuss their possible therapeutic potential for central nervous system (CNS) disorders

Modafinil Administration to Preadolescent Rat Impairs Non-Selective Attention, Frontal Cortex D2 Expression and Mesolimbic GABA Levels

The misuse of psychostimulants is an increasing behavior among young people, highlighting in some countries the abuse of modafinil (MOD) as a neuropotentiator. However, several clinical trials are investigating MOD as an alternative pharmacological treatment for attentional deficit and hyperactivity disorder (ADHD) in children and adolescents. On the other hand, the early use of psychostimulants and the misdiagnosis rates in ADHD make it crucial to investigate the brain effects of this type of drug in young healthy individuals. The aim of this work was to evaluate the effects of chronic MOD treatment on neurochemicals (γ-aminobutyric acid and glutamate), dopamine receptor 2 (D2) expression and behavior (non-selective attention “NSA”) in the mesocorticolimbic system of young healthy Sprague–Dawley rats. Preadolescent male rats were injected with MOD (75 mg/kg, i.p.) or a vehicle for 14 days (from postnatal day 22 to 35). At postnatal day 36, we measured the GLU and GABA contents and their extracellular levels in the nucleus accumbens (NAc). In addition, the GLU and GABA contents were measured in the ventral tegmental area (VTA) and D2 protein levels in the prefrontal cortex (PFC). Chronic use of MOD during adolescence induces behavioral and neurochemical changes associated with the mesocorticolimbic system, such as a reduction in PFC D2 expression, VTA GABA levels and NSA. These results contribute to the understanding of the neurological effects of chronic MOD use on a young healthy brain

Intraspecific variation in exploratory behavior and elevational affinity in a widely distributed songbird

Populations of the same species can vary substantially in their behavioral and morphometric traits when they are subject to different environmental pressures, which may lead to the development of different adaptive strategies. We quantified variation in exploratory behavior and morphometric traits among two rufous-collared sparrow populations that occur at low and high elevations in central Chile. Moreover, we used census and delta H-2 values of feather and blood to evaluate migration. We found that individual sparrows inhabiting high elevations were larger and showed more intense exploratory behavior in comparison with those that were captured at lower elevation. Moreover, we observed a steady decline in sparrow abundance during the winter and similar delta H-2 values for blood collected in the winter and summer at this site, which were significantly lower than blood delta H-2 values observed at low elevation. This pattern suggests that individuals do not move long distances during winter, and likely they remain at similar elevations in refuge habitats. As predicted, our results support the existent of different adaptive strategies among populations of the same species, and suggest that the combination of behavioral, morphometric, and stable isotope data is a novel and robust integrative approach to assess differences in adaptation across environmental gradients.FONDECYT-Chile 1140548 1160115 Institute of Ecology and Biodiversity ICM-P05-002-Chile PFB-23-CONICYT-Chile Fondo Basal FB 0002-2014 21130127 CONICYT-Chil

Cost-effectiveness analysis of the treatment of mild and moderate Alzheimer’s disease in Brazil

Objective: To perform a cost-effectiveness analysis of donepezil and rivastigmine therapy for mild and moderate Alzheimer’s disease (AD) from the perspective of the Brazilian Unified Health System. Method: A hypothetical cohort of 1,000 individuals of both sexes, aged >65 years, and diagnosed with AD was simulated using a Markov model. The time horizon was 10 years, with 1-year cycles. A deterministic and probabilistic sensitivity analysis was performed. Results: For mild AD, the study showed an increase in quality-adjusted life years (QALYs) of 0.61 QALY/21,907.38 Brazilian reais (BRL) for patients treated with donepezil and 0.58 QALY/BRL 24,683.33 for patients treated with rivastigmine. In the moderate AD group, QALY increases of 0.05/BRL 27,414.96 were observed for patients treated with donepezil and 0.06/BRL 34,222.96 for patients treated with rivastigmine. Conclusions: The findings of this study contradict the standard of care for mild and moderate AD in Brazil, which is based on rivastigmine. A pharmacological treatment option based on current Brazilian clinical practice guidelines for AD suggests that rivastigmine is less cost-effective (0.39 QALY/BRL 32,685.77) than donepezil. Probabilistic analysis indicates that donepezil is the most cost-effective treatment for mild and moderate AD