Curcuma longa ingestion protects in vitro hepatocyte membrane peroxidation Ingestão de Curcuma longa protege contra peroxidação de membrana de hepatócito

The goal of the present study was to evaluate the effect of turmeric ingestion on lipid peroxidation and GSH content, promoted by in vitro acetaminophen, on hepatocytes primary culture from well-nourished and malnourished rats. Four groups of Holtzman male rats were used: 1) WNG, well-nourished, fed lab chow diet ad libitum; 2) MNG, malnourished, fed 60% of the diet consumed by WNG; 3) WNG+T fed the same diet of WNG, but containing 1% of turmeric; 4) MNG+T fed 60% of the diet consumed by WNG+T. The animals were sacrificed at 90 days of age, the livers excised and hepatocytes primary cultures were prepared. Half of the plates of hepatocytes culture were treated with acetaminophen. Dose-response curve showed that 6 mM acetaminophen increased peroxidation around 54% and decreased GSH content around 63%. The model of malnutrition used, by restricting food ingestion (40%), decreased body weight in 33% and peroxidation index around 42% and increased GSH content around 43%. Turmeric ingestion decreased hepatocyte peroxidation in both well-nourished (42%) and malnourished rats (33%) and was able to avoid the acetaminophen pro-oxidant effect in both well-nourished and malnourished animals. Turmeric ingestion played a beneficial role to the organism and, therefore, can be considered a functional food.<br>O objetivo do presente estudo foi avaliar o efeito da ingestão de cúrcuma sobre a peroxidação lipídica e conteúdo de GSH, por ação tóxica in vitro de paracetamol, utilizando cultura primária de hepatócitos. Quatro grupos de ratos Holtzman foram usados: 1) GNN, normonutrido, alimentado ad libitum com ração de laboratório; 2) GDN, desnutrido, alimentado com 60% da quantidade de ração consumida por GNN; 3) GNN+C, alimentado como GNN, mas contendo 1% de cúrcuma na dieta; 4) GDN+C, alimentado como GDN, mas contendo 1% de cúrcuma na dieta. Os animais foram sacrificados aos 90 dias de vida, e cultura de hepatócitos preparada. Metade das placas de cultura foi tratada com paracetamol. A curva dose-resposta mostrou que 6 mM de paracetamol aumentou em 54% a peroxidação e diminuiu em 63% o conteúdo de GSH. A restrição na ingestão de alimentos (40%) diminuiu o peso corporal (33%) ao sacrifício e o índice de peroxidação cerca de 42%, entretanto, aumentou o conteúdo de GSH cerca de 43%. A ingestão de cúrcuma diminuiu a peroxidação em ambos ratos normonutridos (42%) e desnutridos (33%) e evitou o efeito pro-oxidante de paracetamol em ambos os grupos. A cúrcuma exerceu efeito protetor antioxidante sobre o organismo

THE MOUSE AS AN EXPERIMENTAL MODEL FOR TITYUS SERRULATUS SCORPION ENVENOMING

The scorpion toxin induces a number of physiological parameters alterations, as disturbance of cardiac rhythm, heart failure, shock, pancreatic hypersecretion, abortion, respiratory arrhytmias and pulmonary edema. As the purification of the venom fractions is a laborious process, one alternative for this would be the utilization of small animals. We utilized in the present study thity-six mice that received progressive doses of scorpion toxin TsTX), i.p. or i.v., and were observed for three hours or sacrificed, and the pulmonary alterations were determined by the lung-body index and by histological analysis of the lungs in order to determine if the mouse can be an esperimental model for scorpion envenomation. The data were analyzed by One Way analysis of variance with p<0,05 indicating significance. These experiments showed no differences in clinical signs of scorpion envenomation between mice and other mammalians, the effects were dose-dependent and the i.v. administration needed less quantity to produce the same changings. In the pulmonary histology we observed septal but not alveolar edema, and we presumed that these differences are due to species-specific variations.<br>A toxina do escorpião induz a várias alterações fisiológicas, como disturbio do ritmo cardíaco, insuficiência cardíaca, choque, hipersecreção pancreática, aborto, arritmias respiratórias e edema pulmonar. A purificação de frações do veneno é um processo trabalhoso. Como alternativa utilizam-se animais pequenos. No presente estudo utilizou-se 36 camundongos que receberam doses progressivas de toxinas do escorpião (TsTX), intraperitoneal ou intravenosa e foram observados por tres horas ou sacrificados. As alteraçòes pulmonares foram determinadas pela fórmula peso do pulmão x 100/ peso corporal e pela análise hitológica dos pulmões a fim de determinar que o camundongo pode ser um modelo experimental do envenenamento pelo escorpião. Os dados foram analizados pela análise de variância considerando-se p<0,05 indicando significancia. Os experimentos não mostraram diferença nos sinais clínicos do envenenamento comparando-se o camundongo com outros mamíferos. Os efeitos foram dose-dependente e que pela via venosa necessita-se menos quantidade para produzir as mesmas alterações. Nos aspectos histológicos pulmonares observou-se edema septal e não alveolar. Presume-se que as diferenças observadas são devidas a variações específicas das espécies

The role of dorsomedial hypotalamus ionotropic glutamate receptors in the hypertensive and tachycardic responses evoked by Tityustoxin intracerebroventricular injection.

The scorpion envenoming syndrome is an important worldwide public health problem due to its high incidence and potential severity of symptoms. Some studies address the high sensitivity of the central nervous system to this toxin action. It is known that cardiorespiratory manifestations involve the activation of the autonomic nervous system. However, the origin of this modulation remains unclear. Considering the important participation of the dorsomedial hypotalamus (DMH) in the cardiovascular responses during emergencial situations, the aim of this work is to investigate the involvement of the DMH on cardiovascular responses induced by intracerebroventricular (icv) injection of Tityustoxin (TsTX, a a-type toxin extracted from the Tityus serrulatus scorpion venom). Urethane-anaesthetized male Wistar rats (n = 30) were treated with PBS, muscimol or ionotropic glutamate receptor antagonists, bilaterally in DMH and later, with an icv injection of TsTX, or treated only with PBS in both regions. TsTX evoked a marked increase in mean arterial pressure and heart rate in all control rats. Interestingly, injection of muscimol, a GABAA receptor agonist, did not change the pressor and tachycardic responses evoked by TsTX. Remarkably, the injection ionotropic glutamate receptors antagonists in DMH abolished the pressor and the tachycardic response evoked by TsTX. Our data suggest that the central circuit recruited by TsTX, whose activation results in an array of physiological and behavioral alterations, depend on the activation of DMH ionotropic glutamate receptors. Moreover, our data provide new insights on the central mechanisms involved in the development of symptoms in the severe scorpion envenomation syndrom

Brainstem structures are primarily affected in an experimental model of severe scorpion envenomation

Severe scorpion envenoming (SSE) is more frequent in children and is characterized by systemic dysfunctions with a mortality rate of up to 9%. Recent evidence shows that the central nervous sys-tem (CNS) plays a key role in triggering the cascade of symptoms present in SSE. The age-dependent role of the CNS in SSE lethality may be summarized in 3 hypotheses: (1) the shown increased blood brain barrier permeability of infants to the toxins would especially and primarily compromise neurovegetative control areas, (2) the neurons within these areas have high affinity to the toxins, and (3) the neurovascular interaction is such that SSE metabolically com-promises proper function of toxin-targeted areas. A pharmacologi-cal magnetic resonance imaging paradigm was used to evaluate localized hemodynamic changes in relative cerebral blood volume (rCBV) for 30 min after the injection of TsTX, the most lethal toxin from the venom of the Tityus serrulatus scorpion. The brainste

Ligation of the abdominal esophagus decreases scorpion toxin-induced gastric secretion in rats Ligadura do esôfago abdominal diminui a secreção gástrica induzida por toxina de escorpião em ratos

PURPOSE: Scorpion toxin purified from Tityus serrulatus venom (Tx) induces an increase in volume, acidity and pepsin secretion in the gastric juice of rats. Ligation of oesophagus has been shown to reduce the acid gastric secretion in rats. The aim of this paper was to determine the influence of the esophageal ligation on gastric secretion induced by Tx in rats METHODS: Forty-four male albino rats were given water ad libitum, but no food for 20 to 24 hours, anesthetized with urethane and the trachea and jugular vein cannulated. Cervical or abdominal esophageal ligation or sham-operations were performed before and after the injection of 0.25 mg/kg of scorpion toxin (fraction T1) into the jugular vein. One hour later, the volume, acidity, pH and peptic activity of gastric juice were determined. RESULTS: The scorpion toxin induced an increase in gastric juice volume, acidity and pepsin output and a decrease in pH when injected into the vein of intact animals or in sham-operated animals. Cervical esophagus ligation did not interfere with the effects of toxin, however, ligation of the abdominal esophageal decreased the toxin effect on the rat stomach. CONCLUSION: Ligation of the abdominal esophagus decreases the gastric secretion induced by scorpion toxin.<br>OBJETIVO: A toxina de escorpião purificada do veneno do escorpião Tityus serrulatus (Tx) induz um aumento no volume, acidez e secreção de pepsina no suco gástrico de ratos. A ligadura do esôfago diminui a secreção ácida do estômago em ratos. O objetivo deste trabalho foi determinar a influência da ligadura do esôfago sobre a secreção gástrica induzida pela Tx em ratos. MÉTODOS: 44 ratos machos, brancos foram administrados água ad libitum, mas não alimentados por 20 a 24 horas, anestesiados com uretana e canulados a traquéia e a veia jugular. Foram realizadas as ligaduras do esôfago cervical ou abdominal ou operações simuladas antes e após a administração na veia jugular de 0,25 mg/kg de toxina de escorpião (fração T1). Uma hora após foram determinados o volume, acidez, pH e atividade péptica do suco gástrico. RESULTADOS: A toxina de escorpi��o induziu um aumento do volume do suco gástrico, da acidez gástrica e da produção de pepsina e uma diminuição do pH quando injetada na veia de animais não operados ou com operação simulada. A ligadura do esôfago cervical não interferiu nos efeitos da toxina, enquanto a ligadura do esôfago abdominal diminuiu os efeitos da toxina no estômago do rato. CONCLUSÃO: A ligadura do esôfago abdominal diminui a secreção gástrica estimulada pela toxina de escorpião