Antinociceptive activity of Riparin II from Aniba riparia: Further elucidation of the possible mechanisms.

Riparin II (RipII) has an anti-inflammatory activity potentially due its ability to decrease TNF-α and IL-1ß production and its histamine antagonism. The objective of this study was to evaluate the role of RipII in the pain process and the possible antinociceptive mechanisms involved, using classic models of nociception. Male Swiss mice were used in the assays. Determinate the acute toxicity according to the OECD 425 test guideline. The models used were the acetic acid-, formalin-, hot plate and glutamate-induced nociception. For evaluation of antinociceptive effect, the involvement of TRPV1, TRPA1, TRPM8, ASICS, Bradykinin, PKC and PKA were performed using the paw licking using agonists. The acute toxicity study did not detect any clinical signs or changes in behavior or mortality. RipII, administered orally (25 and 50 mg/kg) caused a reduction of nociception induced by acetic acid, formalin (on the second phase) and glutamate. In the investigation of antinociceptive mechanism, we used capsaicin (2.2 µg/paw), cinnamaldehyde (10 nmol/paw), menthol (1.2 µmol/paw), ASICS (2% acetic acid, pH 1.98) and bradykinin (10 µg/paw). The results showed that TRPV1, TRPA1, TRPM8, ASICS and bradykinin play a role in the antinociceptive effect of RipII. The results also showed that PKA is involved too. These data demonstrate that RipII has a low or not toxicity and produced an important antinociceptive effect through mechanisms that probably involve an interaction, at least in part, TRPV1, TRPA1, TRPM8, ASICS, bradykinin and PKA participate in the RipII's antinociceptive effect.

In vitro anti-Candida activity of selective serotonin reuptake inhibitors against fluconazole-resistant strains and their activity against biofilm-forming isolates.

Recent research has shown broad antifungal activity of the classic antidepressants selective serotonin reuptake inhibitors (SSRIs). This fact, combined with the increased cross-resistance frequency of the genre Candida regarding the main treatment today, fluconazole, requires the development of novel therapeutic strategies. In that context, this study aimed to assess the antifungal potential of fluoxetine, sertraline, and paroxetine against fluconazole-resistant Candida spp. planktonic cells, as well as to assess the mechanism of action and the viability of biofilms treated with fluoxetine. After 24 h, the fluconazole-resistant Candida spp. strains showed minimum inhibitory concentration (MIC) in the ranges of 20-160 µg/mL for fluoxetine, 10-20 µg/mL for sertraline, and 10-100.8 µg/mL for paroxetine by the broth microdilution method (M27-A3). According to our data by flow cytometry, each of the SSRIs cause fungal death after damaging the plasma and mitochondrial membrane, which activates apoptotic signaling pathways and leads to dose-dependant cell viability loss. Regarding biofilm-forming isolates, the fluoxetine reduce mature biofilm of all the species tested. Therefore, it is concluded that SSRIs are capable of inhibit the growth in vitro of Candida spp., both in planktonic form, as biofilm, inducing cellular death by apoptosis.

Treadmill in Parkinson's: influence on gait, balance, BDNF and Reduced Glutathione / Esteira em Parkinson: influência sobre marcha, equilíbrio, BDNF e Glutationa Reduzida

Abstract Introduction: Parkinson's disease (PD) is characterized by nigrostriatal degeneration, with dopaminergic depletion, and inflammatory and oxidative changes in the brain, leading to movement and coordination disorders. Recent studies have shown that treadmill training can be beneficial for these patients, but there is little evidence assessing the related blood parameters, such as oxidative stress and neurotrophin levels. Objective: Assess the influence of treadmill training for patients with Parkinson's on gait, balance, Brain-Derived Neurotrophic Factor (BDNF) and reduced glutathione. Methods: Twenty-two patients with PD (Hoehn and Yahr II and III), older than 40 years, were randomly allocated to two groups: CG (n = 12) - drug treatment and IG (n = 10) - treadmill. Assessments related to functional capacity (quality of life, static and dynamic analysis of gait) and blood parameters such as GSH and BDNF were conducted before and after the eight-week intervention. Results: The demographic data of the groups were homogeneous in terms of age, sex, height, weight, time since disease onset, mini mental examination and the geriatric depression scale. Significant intergroup differences were found for the mental component summary, surface variation, latero-lateral oscillation, antero-posterior oscillation and mean velocity in the post-intervention period. The IG exhibited a strong association between BDNF and GSH, with statistically significant values. Conclusion: It was concluded that controlled treadmill walking improves static balance, quality of life and plasma BDNF and GSH levels in patients with PD.

Resumo Introdução: A doença de Parkinson (DP) é caracterizada pela degeneração nigroestriatal, com depleção dopaminérgica, alterações inflamatórias e oxidativas cerebrais levando a prejuízo no controle do movimento e coordenação. Trabalhos recentes mostram que a atividade física em esteira pode ser benéfica para estes pacientes, mas há poucas evidências avaliando os parâmetros sanguíneos relacionados, como estresse oxidativo e níveis de neurotrofinas. Objetivo: Avaliar a influência da esteira em Parkinson sobre a marcha, equilíbrio, Brain-Derived Neurotrophic Factor (BDNF) e Glutationa Reduzida. Métodos: Vinte e dois pacientes com DP (Hoehn e Yahr II e III), acima de 40 anos, foram aleatorizados em dois grupos: GC (n = 12) - tratamento medicamento e GI (n = 10) - esteira ergométrica. As avaliações relacionadas à capacidade funcional (qualidade de vida, análise estática e dinâmica da marcha) e parâmetros sanguíneos como GSH e BDNF foram realizadas antes e após as oito semanas de intervenção. Resultados: Os dados demográficos dos grupos foram homogêneos quanto às variáveis idade, gênero, altura, peso, tempo de doença, teste mini mental e teste da escala de depressão. Diferenças significativas foram encontradas para o coeficiente mental sumarizado, variação de superfície, oscilação látero-lateral, oscilação ântero-posterior e velocidade média entre os grupos no período pós-intervenção. No GI, viu-se associação forte entre BDNF e GSH com valores de significância estatística. Conclusão: Conclui-se que a caminhada controlada na esteira melhora o equilíbrio estático, qualidade de vida e os níveis plasmáticos de BDNF e GSH em pacientes com DP.

Synergistic effect of the flavonoid catechin, quercetin, or epigallocatechin gallate with fluconazole induces apoptosis in Candida tropicalis resistant to fluconazole.

Flavonoids are a class of phenolic compounds commonly found in fruits, vegetables, grains, flowers, tea, and wine. They differ in their chemical structures and characteristics. Such compounds show various biological functions and have antioxidant, antimicrobial, anti-inflammatory, and antiapoptotic properties. The aim of this study was to evaluate the in vitro interactions of flavonoids with fluconazole against Candida tropicalis strains resistant to fluconazole, investigating the mechanism of synergism. Three combinations formed by the flavonoids (+)-catechin hydrated, hydrated quercetin, and (-)-epigallocatechin gallate at a fixed concentration with fluconazole were tested. Flavonoids alone had no antifungal activity within the concentration range tested, but when they were used as a cotreatment with fluconazole, there was significant synergistic activity. From this result, we set out to evaluate the possible mechanisms of cell death involved in this synergism. Isolated flavonoids did not induce morphological changes or changes in membrane integrity in the strains tested, but when they were used as a cotreatment with fluconazole, these changes were quite significant. When evaluating mitochondrial damage and the production of reactive oxygen species (ROS) only in the cotreatment, changes were observed. Flavonoids combined with fluconazole were shown to cause a significant increase in the rate of damage and the frequency of DNA damage in the tested strains. The cotreatment also induced an increase in the externalization of phosphatidylserine, an important marker of early apoptosis. It is concluded that flavonoids, when combined with fluconazole, show activity against strains of C. tropicalis resistant to fluconazole, promoting apoptosis by exposure of phosphatidylserine in the plasma membrane and morphological changes, mitochondrial depolarization, intracellular accumulation of ROS, condensation, and DNA fragmentation.