Evidence from the literature indicates that mitochondrial dysfunction occurs in schizophrenia and other psychiatric disorders. To produce an animal model that simulates psychotic symptoms analogous to those seen in schizophrenic patients, sub-anesthetic doses of N-methyl-D-aspartate (NMDA) receptor antagonists (such as ketamine) have been used. The aim of this study was to evaluate behavioral changes and mitochondrial dysfunction in rats administered ketamine for 7 consecutive days. Behavioral evaluation was performed using an activity monitor 1, 3 and 6 h after the last injection. The activities of mitochondrial respiratory chain complexes I, II, I-III and IV in multiple brain regions (prefrontal cortex, striatum and hippocampus) were also evaluated. Our results showed that hyperlocomotion occurred in the ketamine group 1 and 3 h after the last injection. Stereotypic movements were elevated only when animals were evaluated 1 h after receiving ketamine. In addition, we found that ketamine administration affects the respiratory chain, altering the activity of respiratory chain complexes in the striatum and hippocampus after 1 h, those in the prefrontal cortex and hippocampus after 3 h and those in the prefrontal cortex and striatum 6 h after the last administration of ketamine. These findings suggest that ketamine alters the behavior of rats and changes the activity of respiratory chain complexes in multiple brain regions at different time points.

Alzheimer disease (AD) is a progressive neurodegenerative disease associated with cognitive impairment in multiple domains, such as memory and executive functions. Studies reveal damage in the electron transport chain of patients with AD, suggesting that this mitochondrial dysfunction plays an important role in the pathophysiology of the disease. Blood samples were taken from patients with AD (n = 20) and older subjects without dementia (n = 40) to evaluate the activity of complexes I, II, II-III, and IV of the mitochondrial respiratory chain in isolated lymphocytes. Results from the patient and control groups were compared. The activity of complexes II and IV was increased among patients compared to the control group. No significant difference was observed between controls who were not using psychotropic medication and patients. Our findings point out a mechanism of cellular compensation in which the mitochondrial respiratory chain requires an increase in electron transport to supply the energy needed for cellular functioning. Additional studies are needed to better clarify the mechanisms involved in the mitochondrial dynamics of AD.

Schizophrenia is a debilitating mental disorder characterized by positive (delusions, hallucinations, disorganized speech) and negative (affective flattering, avolition and social withdrawal) symptoms as well as cognitive deficits. The frequency, severity and topography characterize the disorder as heterogeneous, the pathophysiology of schizophrenia is poorly understood. Sub-anesthetic doses of ketamine produce hyperactivity, stereotypy and abnormal social interaction and it is used as a model of schizophrenia. In this study, we induced an animal model by acute sub-anesthetic doses of ketamine and tested different behavioral parameters. We also evaluated the activity of creatine kinase (CK) in brain of rats treated with ketamine. Our results demonstrated that administration of 10, 25 and 50 mg/kg of ketamine induced an increase of covered distance in habituated and non-habituated rats to the behavioral apparatus. Ketamine administration induced significant social deficits and stereotypic behavioral in all doses tested. Finally we evaluated the effect of different doses of ketamine on creatinine kinase (CK) activity and we observed that CK activity is increased inspecific regions of the brain. Our study suggests that our animal model may be used as a model of schizophrenia and that cerebral energy metabolism might be altered in the brain of schizophrenic patients, probably leading to alterations that might be involved in the pathogenesis of schizophrenia.

The sequelae of coronavirus disease-2019 (COVID-19) are another socio-economic problem of the pandemic. Fatigue and dyspnea are the most prevalent symptoms. It is not known whether exercise can be used to treat long COVID-19. This study aimed to investigate the effects of an 8-week face-to-face rehabilitation program on COVID-19 compared to a remote monitoring group. A total of 37 participants (24.3% hospitalized) were assessed before and after rehabilitation (n = 22; 40.8 ± 10.0 years) or remote monitoring (n = 15; 45.4 ± 10.5 years). The participants were allocated according to their preferences. Both groups showed improved fatigue and exercise capacity (Incremental Shuttle Walk Test). Participants in the face-to-face rehabilitation group showed improved dyspnea (Pulmonary Functional Status and Dyspnea Questionnaire), anxiety (Hospital Anxiety and Depression Scale), attention, and short-term memory (d2-R and Rey's Auditory-Verbal Learning Test). Of the main sequelae, fatigue improves naturally, whereas dyspnea requires rehabilitation. Our results demonstrated the benefits of exercise for COVID-19 sequelae.

Chronic administration of ketamine in an animal model of schizophrenia generates increased AChE levels in different brain tissues of rats that lead to cognitive deficits. Therefore, further studies are needed to elucidate the complex mechanisms associated with schizophrenia.

These results suggest that olanzapine is correlated with weight gain and the risks associated with obesity.

Resumo O metilfenidato é um fármaco indicado no tratamento do transtorno de déficit de atenção e hiperatividade (TDAH) e da narcolepsia. Atua no sistema nervoso central inibindo a recaptação de dopamina e noradrenalina, o que provoca um efeito psicoestimulante. Estudos anteriores demonstraram um aumento no consumo da droga por indivíduos saudáveis que buscam aprimoramento cognitivo. O objetivo deste estudo foi investigar a relação entre o uso não prescrito de metilfenidato e o desempenho acadêmico de estudantes de medicina de uma universidade do sul de Santa Catarina. Trata-se de uma pesquisa descritiva de caráter quantitativo. Participaram da pesquisa 243 acadêmicos do segundo ao oitavo semestre do curso de medicina; os dados foram coletados por meio de um questionário e analisados com ajuda do software SPSS versão 21.0. A prevalência de uso não prescrito do metilfenidato foi de 2,9%, enquanto 17,3% dos pesquisados afirmaram já ter utilizado o medicamento alguma vez na vida. As motivações para consumo mais citadas foram melhorar o desempenho cognitivo (10%) e ficar acordado por mais tempo (4,1%), e a forma de obtenção mais comum foi por meio de amigos (56,5%). O psicoestimulante não apresentou efeitos de aprimoramento cognitivo, uma vez que participantes que nunca utilizaram o fármaco apresentaram um desempenho acadêmico superior (8,80) se comparados àqueles que usam (7,92) ou já usaram (8,01). Os resultados corroboram a hipótese de efeito relacionado a sensações de bem-estar em pessoas saudáveis, o que torna preocupante a injustificada exposição aos efeitos adversos da droga. Ressalta-se a necessidade de ações que visem à promoção de saúde mental aos universitários.

Objective: This study aimed to evaluate the effects of physical rehabilitation for adults with sequelae after COVID-19. Methods: This clinical, nonrandomized, controlled, and open study will examine 82 participants who have met the inclusion criteria and who will be divided into treatment and control groups according to participant preference. The intervention group will receive face-to-face care; the control group will receive remote educational guidance for 8 weeks, with pre-post evaluations. The primary outcomes are dyspnea, fatigue, and exercise capacity; the secondary outcomes are lung function, heart rate variability, handgrip strength, knee extensor strength and electrical activity, physical activity, functional limitation, cognitive function, depression and anxiety, and biochemical measures of hypoxia, inflammation, oxidative stress, blood glucose, and lactate blood tests. The survey will follow the Standard Protocol Items for Randomized Trials guidelines, and the results will be reported according to the Consolidated Standards of Reporting Trials guidelines. Effects will be assessed based on the intent-to-treat data collected. Analysis of covariance will be used for the initial and final evaluations, with a significance level of 5%. Results and Conclusions: The results will show the effectiveness of rehabilitation in adults with post-COVID-19 sequelae.