RESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Trichilia catigua A. Juss (Meliaceae) is used in Brazilian folk medicine to alleviate fatigue and emotional stress and improve memory. Previous studies from our laboratory reported that an ethyl-acetate fraction (EAF) of T. catigua that was given before cerebral ischemia in vivo prevented memory loss and reduced oxidative stress and neuroinflammation. Despite the value of these findings of a neuroprotective effect of T. catigua, treatment that was given immediately before or immediately after ischemia limits its clinical relevance. Thus, unknown is whether T. catigua possesses a specific time window of efficacy (TWE) when administered postischemia. AIM OF THE STUDY: Given continuity to previous studies, we investigated whether an EAF of T. catigua maintains its neuroprotective properties if treatment begins at different time windows of efficacy after ischemia. We also evaluated, for the first time, whether T. catigua possesses neuroplasticity/neurotrophic properties. MATERIAL AND METHODS: Rats were subjected to transient global brain ischemia (TGCI) and then given a single dose of the EAF (400 mg/kg) or vehicle (1 ml/kg) orally 1, 4, or 6 h postischemia. The levels of protein PCG, GSH, and GSSG, and activity of SOD and CAT were assayed as markers of oxidative stress on the day after ischemia. In another experiment, naive rats underwent spatial learning training in a radial maze task and then subjected to TGCI. Delayed treatment with the EAF began 4 or 6 h later and continued for 7 days. Retrograde memory performance was assessed 10, 17, and 24 days postischemia. Afterward, brains were examined for neurodegeneration and neuronal dendritic morphology in the hippocampus and cerebral cortex. Another group received the EAF at 4 h of reperfusion, and 4 days later their brains were examined for GFAP and Iba-1 immunoreactivity. Lastly, ischemic rats received the EAF 4 h after ischemia and neural plasticity-related proteins, BDNF, SYN, PSD 95, and NeuN were measured in the hippocampus 7 and 14 days after ischemia. RESULTS: A single EAF administration 1, 4, or 6 h postischemia alleviated oxidative stress that was caused by ischemia, expressed as a reduction of the amount of the PCG and GSSG, normalization of the GSH/GSSG ratio, and the restoration of SOD activity. Ischemia caused the persistent loss of memory (i.e., amnesia), an outcome that was consistently ameliorated by treatment with the EAF that was initiated 4 or 6 h postischemia. The 4 h delay in EAF treatment positively impacted dendritic morphology in neurons that survived ischemia. TGCI reduced BDNF, SYN, PSD-95, and NeuN protein levels in the hippocampus and cerebral cortex. The EAF normalized SYN and PSD-95 protein levels. Ischemia-induced neurodegeneration and glial cell activation were not prevented by EAF treatment. CONCLUSION: The present study corroborates prior data that demonstrated the neuroprotective potential of T. catigua and extends these data by showing that the delayed administration of EAF postischemia effectively prevented memory impairment and decreased oxidative stress, dendritic deterioration, and synaptic protein loss within a TWE that ranged from 1 to 6 h. This specific TWE in preclinical research may have clinical relevance by suggesting the possible utility of this plant for the development of neuroprotective strategies in the setting of ischemic brain diseases. Another innovative finding of the present study was the possible neurotrophic/neuroplastic properties of T. catigua.
Assuntos
Isquemia Encefálica , Meliaceae , Fármacos Neuroprotetores , Ratos , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Dissulfeto de Glutationa/metabolismo , Dissulfeto de Glutationa/farmacologia , Dissulfeto de Glutationa/uso terapêutico , Extratos Vegetais/farmacologia , Isquemia Encefálica/tratamento farmacológico , Estresse Oxidativo , Infarto Cerebral/tratamento farmacológico , Hipocampo , Transtornos da Memória/tratamento farmacológico , Acetatos/farmacologia , Superóxido Dismutase/metabolismo , Plasticidade Neuronal , Fármacos Neuroprotetores/farmacologiaRESUMO
Periodontal diseases are a global oral health problem affecting almost 10% of the global population. Porphyromonas gingivalis is one of the main bacteria involved in the initiation and progression of inflammatory processes as a result of the action of the cysteine proteases lysin- and arginine-gingipain. Surelease/polycarbophil microparticles containing a lyophilized proanthocyanidin-enriched fraction from the rhizomes of Limonium brasiliense, traditionally named "baicuru" (ethyl acetate fraction), were manufactured. The ethyl acetate fraction was characterized by UHPLC by the presence of samarangenins A and B (12.10 ± 0.07 and 21.05 ± 0.44%, respectively) and epigallocatechin-3-O-gallate (13.44 ± 0.27%). Physiochemical aspects of Surelease/polycarbophil microparticles were characterized concerning particle size, zeta potential, entrapment efficiency, ethyl acetate fraction release, and mucoadhesion. Additionally, the presence of the ethyl acetate fraction-loaded microparticles was performed concerning potential influence on viability of human buccal KB cells, P. gingivalis adhesion to KB cells, gingipain activity, and P. gingivalis biofilm formation. In general, all Surelease/polycarbophil microparticles tested showed strong adhesion to porcine cheek mucosa (93.1 ± 4.2% in a 30-min test), associated with a prolonged release of the ethyl acetate fraction (up to 16.5 ± 0.8% in 24 h). Preincubation of KB cells with Surelease/polycarbophil microparticles (25 µg/mL) resulted in an up to 93 ± 2% reduced infection rate by P. gingivalis. Decreased activity of the P. gingivalis-specific virulence factors lysin- and arginine-gingipain proteases by Surelease/polycarbophil microparticles was confirmed. Surelease/polycarbophil microparticles decreased biofilm formation of P. gingivalis (97 ± 2% at 60 µg/mL). Results from this study prove the promising activity of Surelease/polycarbophil microparticles containing ethyl acetate fraction microparticles as a prophylaxis strategy to prevent the recurrence of P. gingivalis.
Assuntos
Plumbaginaceae , Proantocianidinas , Humanos , Animais , Suínos , Cisteína Endopeptidases Gingipaínas , Porphyromonas gingivalis , Adesinas Bacterianas , Proantocianidinas/farmacologia , Cisteína Endopeptidases , Plumbaginaceae/químicaRESUMO
Poincianella pluviosa has already been described as capable of healing skin wounds. In an attempt to prolong contact of the drug with the wound, it was proposed in this study to evaluate wound healing using a crude extract (CE) of P. pluviosa incorporated in carboxymethylcellulose polymer films. The chromatographic profile of the semipurified fraction of P. pluviosa was evaluated by ultra-high performance liquid chromatography (UHPLC), confirming the compounds gallic acid, geraniin, and ellagic acid. The films were evaluated for their physical and mechanical properties, water vapor permeability, moisture absorption capacity, and FTIR spectroscopy. For in vivo experiments, wounds were made on the back of rats and treated daily for 4, 7, 10, or 14 days with film containing CE or control film. At the end of each period, skin permeation analysis and histological analysis were made using re-epithelialisation, cell proliferation, and collagen formation. Statistical significance was determined by GraphPad Prism using t test and Mann-Whitney test. Anti-staphylococcal activity was evaluated with standard strains of Staphylococcus aureus, methicillin-resistant, and coagulase negative. It was demonstrated that the presence of CE in the films increased the capacity to absorb water and decreased resistance and permeability. The CE of the film permeated the skin, reaching the dermis and was able to influence re-epithelisation, cell proliferation, and collagen formation. Satisfactory results were observed against S. aureus strains, particularly coagulase negative. Films with CE of P. pluviosa can be an alternative in the wound healing, protecting against opportunistic infections and giving comfort to the patient.