Os efeitos-colaterais psiquiátricos do rimonabanto

OBJECTIVE: Experimental evidence has suggested that drugs that enhance cannabinoid type-1 (CB1) receptor activity may induce anxiolytic and antidepressant effects, whilst the opposite has been reported with antagonists. Thus, the objective of the present review is to discuss the potential psychiatric side-effects of CB1 receptor antagonists, such as rimonabant, which has been recently marketed in several countries for the treatment of smoking cessation, obesity and associated metabolic disorders. METHOD: Literature searches were performed in PubMed and SciELO databases up to February 2009. The terms searched were "obesity", "rimonabant", "cannabinoids", "unwanted effects", "diabetes", "smoking cessation" and "side-effects". RESULTS: Clinical trials have revealed that rimonabant may promote weight loss in obese patients, although it may also induce symptoms of anxiety and depression. DISCUSSION: Patients taking CB1 receptor antagonists should be carefully investigated for psychiatric side-effects. These drugs should not be prescribed for those already suffering from mental disorders. Nevertheless, the development of new compounds targeting the endocannabinoid system for the treatment of several conditions would be necessary and opportune.OBJETIVO: Evidência experimental sugere que drogas que aumentam a atividade dos receptores canabinóides tipo 1 (CB1) podem induzir efeitos ansiolíticos ou antidepressivos, enquanto que o oposto tem sido relatado com antagonistas. Assim, o objetivo da presente revisão é discutir os potenciais efeitos-colaterais psiquiátricos de antagonistas do receptor CB1, como o rimonabanto, que foi recentemente liberado para comercialização em diversos países para o tratamento do tabagismo, obesidade e de desordens metabólicas associadas. MÉTODO: Foi realizada uma busca na literatura no PubMed e Scielo até fevereiro de 2009, com os termos "obesity", "rimonabant", "cannabinoids", "unwanted effects", "diabetes" , "smoking cessation" e "side effects". RESULTADOS: Ensaios clínicos revelaram que o rimonabanto pode produzir perda de peso em pacientes obesos, embora também possa induzir sintomas de ansiedade e depressão. DISCUSSÃO: Pacientes tomando antagonistas do receptor CB1 devem ser cuidadosamente examinados quanto aos efeitos-colaterais psiquiátricos. Estas drogas não devem ser prescritas a indivíduos que já sofrem de transtornos mentais. Entretanto, o desenvolvimento de novos compostos que atuem no sistema endocanabinóide para o tratamento das mais diversas condições parece necessário e oportuno

MECANISMOS DE AÇÃO DOS ANTIPSICÓTICOS: HIPÓTESES DOPAMINÉRGICAS

Esta revisão discute algumas das principais hipóteses sobre os mecanismos de ação dos antipsicóticos no tratamento da esquizofrenia. São abordadas as teorias tentando diferenciar os antipsicóticos “atípicos” dos “típicos”, como a do antagonismo de receptores D2 de dopamina e 5-HT 2 de serotonina, a da dissociação rápida do receptor D2 e, por fim, a teoria do agonismo parcial. Elas constituem um exemplo fascinante de como evoluem as idéias sobre os efeitos dos medicamentos. Além disso, mostram que há uma necessidade crescente de conceitos e termos básicos da Farmacologia para que se compreendam as diferenças observadas entre os antipsicóticos. Daí a justificativa para um texto que aborde os aspectos farmacológicos e as suas respectivas implicações.  This review discusses some of the main hypothesis about the mechanisms of action of antipsychotics in the treatment of schizophrenia. The main theories try to identify mechanisms to differentiate between the “atypical” and “typical” antipsychotics, such as the antagonism of D2and 5-HT2 receptors, the rapid dissociation from the D2 receptor and the partial agonism. They constitute an interesting example of how ideas evolve to explain the effects of diverse medicines. Moreover, these theories show how important are the concepts and terms from basic Pharmacology for understanding the differences among the antipsychotics. Hence, the importance of an article approaching the pharmacological aspects and its implications. 

Online information on medical cannabis is not always aligned with scientific evidence and may raise unrealistic expectations

There is a growing literature on the potential medical uses of Cannabis sativa and cannabinoid compounds. Although these have only been approved by regulatory agencies for a few indications, there is a hype about their possible benefits in a variety of conditions and a large market in the wellness industry. As in many cases patients search for information on cannabis products online, we have analyzed the information on medical cannabis available on the Internet. Therefore, this study aims at assessing the quality of the information available online on medical cannabis

A new species of Parianella (Poaceae, Bambusoideae, Olyreae) marks the southernmost distribution of the genus in Brazil

Background and aims – Parianella is a relatively recently described genus of the subtribe Parianinae (Poaceae, Bambusoideae, Olyreae) that includes two species, and it is supposedly endemic to the Bahian Coastal Forests in the central region of Atlantic Forest, Brazil. Herein, we describe and illustrate a new species of the genus, comparing it with the other species of Parianella. We also provide an updated distribution map of the genus and the conservation status of the new taxon. Material and methods – This study was based on the analysis of herbarium specimens and a literature review. The conservation assessment is based on field observations and spatial analyses, following IUCN guidelines and criteria. Key results – During a review of the Poaceae collection of the MBML Herbarium, two Parianinae specimens with interesting features were found. A detailed morphological analysis revealed that these specimens belong to a new species of Parianella. The new taxon was collected in two localities in the southern portion of the Brazilian state of Espírito Santo, one in the municipality of Santa Leopoldina and the other in the Duas Bocas Biological Reserve, municipality of Cariacica. Both localities are situated in the Krenák-Waitaká Forests, one of the three subregions of the central Atlantic Forest region, and an area of great floristic diversity, including bamboo species. Conclusion – Parianella capixaba represents the southernmost distribution of the genus known to date. With the description of this new species, the total number of bamboos in Espírito Santo state rises to 52 species in 18 genera

Protective Properties in Hymenaea martiana Hayne against Multi-drug-resistant Staphylococcus aureus

Antibiotic resistance represents a widespread problem in milk production. The identification of compounds for a topically applied ointment used in mastitis therapy remains elusive. Compounds from the genus Hymenaea can be administered in cases of multi-drug-resistant Staphylococcus aureus infection for ruminant species, but the protective properties are not well known. Wi this research the aim is verify the protective effects of H. martiana against S. aureus infection in bovine mammary epithelial cell line (MAC-T) and to obtain an antioxidant profile evaluation in vitro. The MAC-T cells were challenged with S. aureus after being exposed to the extract of the H. martiana in the protective assay. For the verification of the viability of the MAC-T cells, the MTT assay was performed, and was used dilutions of the plant extract, starting at 2.5%. The extract of H. martiana was evaluated for antioxidant aspect in different dilutions by FRAP, ORAC and DPPH. A variety of flavonoids (quercetin, luteolin, etc.) have been identified as the main components by using mass spectrometry, reinforcing our in vitro findings that flavonoids, especially quercetin, have a medicinal profile capable of killing mastitis-causing bacteria. An excellent antioxidant pattern was observed in the 2.5% solution; however, membrane integrity in MAC-T cells was compromised. Those findings suggest low dilutions of H. martiana extract has a desirable protective effect from S. aureus pathogenesis. Our in vitro studies can be gleaned upon for further in vivo studies