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BACKGROUND: The ketone bodies (KB), ß-hydroxybutyrate (BHB) and acetoacetate, have been proposed for the treatment of acute and chronic neurological disorders, however, the molecular mechanisms involved in KB protection are not well understood. KB can substitute for glucose and support mitochondrial metabolism increasing cell survival. We have reported that the D-isomer of BHB (D-BHB) stimulates autophagic degradation during glucose deprivation in cultured neurons increasing cell viability. Autophagy is a lysosomal degradation process of damaged proteins and organelles activated during nutrient deprivation to obtain building blocks and energy. However, impaired or excessive autophagy can contribute to neuronal death. OBJECTIVE: The aim of the present study was to test whether D-BHB can preserve autophagic function in an in vivo model of excitotoxic damage induced by the administration of the glutamate receptor agonist, N-methyl-Daspartate (NMDA), in the rat striatum. METHODS: D-BHB was administered through an intravenous injection followed by either an intraperitoneal injection (i.v+i.p) or a continuous epidural infusion (i.v+pump), or through a continuous infusion of D-BHB alone. Changes in the autophagy proteins ATG7, ATG5, BECLIN 1 (BECN1), LC3, Sequestrosome1/p62 (SQSTM1/ p62) and the lysosomal membrane protein LAMP2, were evaluated by immunoblot. The lesion volume was measured in cresyl violet-stained brain sections. RESULTS: Autophagy is activated early after NMDA injection but autophagic degradation is impaired due to the cleavage of LAMP2. Twenty-four h after NMDA intrastriatal injection, the autophagic flux is re-established, but LAMP2 cleavage is still observed. The administration of D-BHB through the i.v+pump protocol reduced the content of autophagic proteins and the cleavage of LAMP2, suggesting decreased autophagosome formation and lysosomal membrane preservation, improving autophagic degradation. D-BHB also reduced brain injury. The i.v+i.p administration protocol and the infusion of D-BHB alone showed no effect on autophagy activation or degradation.

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Raman spectroscopy (RS) is a vibrational technique that is suitable for performing biochemical analyses in human tissues and fluids. This work has investigated the identification of biochemical markers due to physical performance in the urine of swimming athletes. This was achieved by means of the Raman features that were found before and after the swimming training compared to the sedentary control subjects. These particular biochemical marker identifications refer to and infer the physiological status of individuals. The urine samples (single stream) were collected before and after the training (velocity, middle distance and distance) of professional swimmers, as well as from sedentary subjects (control). The urine samples were submitted to RS (830 nm excitation, 350 mW, 400-1800 cm-1 spectral range, 4 cm-1 resolution) and the spectra after the training were compared to the spectra before training, and subsequently, to the control subjects. The principal component analysis (PCA) was employed in order to identify the biochemicals that were responsible for the spectral differences. The Raman features of the urine samples after training showed peaks that were related to common urine metabolites, such as urea and creatinine. PCA analysis also revealed Raman features that were attributed to other metabolites, such as creatine, ketone bodies, phosphate and nitrogenous compounds in the swimmers after training. RS was a rapid and reliable technique for the evaluation of urine metabolites that were related to the physical performance of high-level swimmers, which then allowed for an accurate assessment and a control of their physiological efficiencies.

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This study aimed to evaluate the in vitro anthelmintic activity of Mimosa caesalpinifolia (sabiá) ketone extract, which is rich in condensed tannins (CT), on Haemonchus contortus and Trichostrongylus colubriformis. The leaves and stems of M. caesalpinifolia were collected, dried in the shade, and ground to a dry powder from which ketone extracts were obtained for in vitro assays. The extracts were diluted in 5% acetone and PBS to concentrations in the range 0.25-2.80 mg mL-¹ and the inhibition of egg hatchability was assayed. Feces collected from goats naturally infected with H. contortus (55%) and T. colubriformis (45%) were macerated and the helminth eggs were collected to conduct in vitro egg hatchability tests. Nematode larvae collected from the feces were used for a larval exsheathment inhibition assay of M. caesalpinifolia leaf and M. caesalpinifolia leaf and stem ketone extracts at concentrations of 0.6 and 1.2 mg mL-¹; three replicates were performed for each concentration. PBS was used as a negative control. Polyvinylpolypyrrolidone (PVPP) was added to the extracts to assess the effect of phenolic compounds on anthelmintic activity. An inhibitory effect of 80.7% and 82.3% was observed on hatchability after treatment with 1.0 and 2.0 mg mL-¹ M. caesalpinifolia leaf ketone extract, respectively. An inhibition rate lower than 75% was observed for 1.0 mg mL-¹ M. caesalpinifolia leafand stem ketone extract. The M. caesalpinifolia leaf ketone extract larval exsheathment assay resultedin inhibition of 97.3% and 99.8% at concentrations of 0.6 and 1.2 mg mL-¹, respectively. For the leafand stem ketone extract, the larval exsheathment inhibition was 94.3% at 1.2 mg mL-¹. The leaf andleaf and stem extracts showed no inhibitory effects on larval exsheathment after the addition of PVPP.These results showed that cuticular loss was related to the action of the phenolic compounds in the M.caesalpinifolia extracts. M. caesalpinifolia leaf ketone...(AU)

Este trabalho teve como objetivo avaliar a atividade anti-helmíntica in vitro do extrato cetônico, rico em Tanino Condensado (TC) de Mimosa caesalpinifolia (sabiá) sobre Haemonchus contortus e Trichostrongylus colubriformis. Foram coletadas folhas e caules, secas a sombra por sete dias e moídas. O pó seco das folhas e caules foi utilizado para obtenção dos extratos cetônicos e realização dos testes in vitro. Os extratos foram diluídos em acetona 5% e PBS em concentrações entre 0,25 e 2,80 mg mL-¹ para realização do teste de inibição da eclodibilidade de ovos. Fezes coletadas de caprino infectado com H. contortus (55%) e T. colubriformis (45%) foram maceradas e os ovos dos helmintos recuperados, e testes in vitro de eclodibilidade dos ovos realizados. Larvas dos nematódeos recuperadas das fezes foram utilizadas para o teste de inibição do desembainhamento larvar com os extratos de folhas, e folhas com caule de M. caesalpinifolia em concentrações de 0,6 a 1,2 mg mL-¹ com três repetições para cada concentração. O controle negativo foi realizado com PBS. Polivinilpolipirrolidona (PVPP) foi adicionado aos extratos para verificar o efeito de compostos fenólicos na atividade anti-helmíntica. No extrato cetônico de folha de M. caesalpinifolia, nas concentrações 1,0 e 2,0 mg mL-¹, foi observado uma taxa de inibição de eclodibilidade dos ovos de 80,7 e 82,3%, respectivamente. O extrato cetônico da folha de M. caesalpinifolia inibiu a eclodibilidade dos ovos,entretanto o extrato da folha e caule apresentou eficiência inferior, demonstrando que os compostosativos estão mais presentes nas folhas. Para a inibição do desembainhamento larvar os extratos cetônicosda M. caesalpinifolia foram eficazes na maior concentração testada. Com esses resultados, pesquisasin vivo devem ser realizadas para comprovação da atividade anti-helmíntica dessa planta em caprinos.(AU)

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RESUMO

This study aimed to evaluate the in vitro anthelmintic activity of Mimosa caesalpinifolia (sabiá) ketone extract, which is rich in condensed tannins (CT), on Haemonchus contortus and Trichostrongylus colubriformis. The leaves and stems of M. caesalpinifolia were collected, dried in the shade, and ground to a dry powder from which ketone extracts were obtained for in vitro assays. The extracts were diluted in 5% acetone and PBS to concentrations in the range 0.25-2.80 mg mL-¹ and the inhibition of egg hatchability was assayed. Feces collected from goats naturally infected with H. contortus (55%) and T. colubriformis (45%) were macerated and the helminth eggs were collected to conduct in vitro egg hatchability tests. Nematode larvae collected from the feces were used for a larval exsheathment inhibition assay of M. caesalpinifolia leaf and M. caesalpinifolia leaf and stem ketone extracts at concentrations of 0.6 and 1.2 mg mL-¹; three replicates were performed for each concentration. PBS was used as a negative control. Polyvinylpolypyrrolidone (PVPP) was added to the extracts to assess the effect of phenolic compounds on anthelmintic activity. An inhibitory effect of 80.7% and 82.3% was observed on hatchability after treatment with 1.0 and 2.0 mg mL-¹ M. caesalpinifolia leaf ketone extract, respectively. An inhibition rate lower than 75% was observed for 1.0 mg mL-¹ M. caesalpinifolia leafand stem ketone extract. The M. caesalpinifolia leaf ketone extract larval exsheathment assay resultedin inhibition of 97.3% and 99.8% at concentrations of 0.6 and 1.2 mg mL-¹, respectively. For the leafand stem ketone extract, the larval exsheathment inhibition was 94.3% at 1.2 mg mL-¹. The leaf andleaf and stem extracts showed no inhibitory effects on larval exsheathment after the addition of PVPP.These results showed that cuticular loss was related to the action of the phenolic compounds in the M.caesalpinifolia extracts. M. caesalpinifolia leaf ketone...

Este trabalho teve como objetivo avaliar a atividade anti-helmíntica in vitro do extrato cetônico, rico em Tanino Condensado (TC) de Mimosa caesalpinifolia (sabiá) sobre Haemonchus contortus e Trichostrongylus colubriformis. Foram coletadas folhas e caules, secas a sombra por sete dias e moídas. O pó seco das folhas e caules foi utilizado para obtenção dos extratos cetônicos e realização dos testes in vitro. Os extratos foram diluídos em acetona 5% e PBS em concentrações entre 0,25 e 2,80 mg mL-¹ para realização do teste de inibição da eclodibilidade de ovos. Fezes coletadas de caprino infectado com H. contortus (55%) e T. colubriformis (45%) foram maceradas e os ovos dos helmintos recuperados, e testes in vitro de eclodibilidade dos ovos realizados. Larvas dos nematódeos recuperadas das fezes foram utilizadas para o teste de inibição do desembainhamento larvar com os extratos de folhas, e folhas com caule de M. caesalpinifolia em concentrações de 0,6 a 1,2 mg mL-¹ com três repetições para cada concentração. O controle negativo foi realizado com PBS. Polivinilpolipirrolidona (PVPP) foi adicionado aos extratos para verificar o efeito de compostos fenólicos na atividade anti-helmíntica. No extrato cetônico de folha de M. caesalpinifolia, nas concentrações 1,0 e 2,0 mg mL-¹, foi observado uma taxa de inibição de eclodibilidade dos ovos de 80,7 e 82,3%, respectivamente. O extrato cetônico da folha de M. caesalpinifolia inibiu a eclodibilidade dos ovos,entretanto o extrato da folha e caule apresentou eficiência inferior, demonstrando que os compostosativos estão mais presentes nas folhas. Para a inibição do desembainhamento larvar os extratos cetônicosda M. caesalpinifolia foram eficazes na maior concentração testada. Com esses resultados, pesquisasin vivo devem ser realizadas para comprovação da atividade anti-helmíntica dessa planta em caprinos.

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