Anti-inflammatory activity of Jatropha curcas L. in brain glial cells primary cultures.

ETHNOPHARMACOLOGICAL RELEVANCE: Jatropha curcas L. (Euphorbiaceae), a medicinal plant known in Brazil as "Pinhão Manso", is highly adaptable, being cultivated in different tropical and subtropical regions of the world. Antimicrobial, antioxidant and antiinflammatory activities have been attributed to different parts of the plant. In the central nervous sytem (CNS), neuroinflammation is mediated by glial cells, mainly by astrocytes and microglia, a process that plays an important role in neurodegenerative diseases and other CNS disorders. In this study, we investigated the anti-inflammatory activity of the methanolic extract obtained from the leaves of J. curcas L. (MEJc) in primary cultures of glial cells submited to inflammatory stimulus. MATERIALS AND METHODS: Primary cultures of glial cells obtained from the cerebral cortex of neonate Wistar rats were treated with MEJc (0.1-50,000 µg mL-1) and its fractions (FnJc) (0.1 µg mL-1) with or without lipopolysaccharide of Escherichia coli (LPS) (1 µg mL-1). Cell viability was determined with MTT test. Modifications in glial cell morphology were investigated by means of phase contrast microscopy and May-Grünwald staining. The reactivity of astrocytes and microglia were investigated with immunocytochemistry for GFAP, Iba1 and transcription factor NF-kB, as well as with Greiss reaction to determine the nitric oxide (NO) production. RESULTS: MEJc at 0.1-1000 µg mL-1 was non-toxic to glial cells and the DE50 was 10.794 µg mL-1. The treatment with LPS induced the activation of astrocytes and microglia marked by morphological modifications and changes in the expression of GFAP and Iba1, as well as the increase in NF-kB expression and NO production. Treatment with MEJc inhibited the morphological modifications, changes in GFAP and Iba1 expression, and the increase in NF-kB and NO production induced by LPS. CONCLUSION: This study demonstrates that the MEJc and its fractions modulate inflammatory response of astrocytes and microglia to LPS and may be considered as a potential therapeutic strategy for neuroinflammation-related diseases.

Amburana cearensis seed extract protects brain mitochondria from oxidative stress and cerebellar cells from excitotoxicity induced by glutamate.

ETHNOPHARMACOLOGICAL RELEVANCE: Amburana cearensis (Allemao) A.C.Sm. is a medicinal plant of the Brazilian Caatinga reported to present antioxidant and anti-inflammatory activity. This study aimed to evaluate the neuroprotective effect of the extracts obtained from the seeds of A. cearensis in primary cultures of cerebellar cells subjected to excitotoxicity induced by glutamate and brain mitochondria submitted to oxidative stress. MATERIALS: and methods: Primary cultures of cerebellar cells were treated with the ethanol (ETAC), hexane (EHAC), dichloromethane (EDAC) and ethyl acetate (EAAC) extracts of the seeds of A.cearensis and subjected to excitotoxicity induced by glutamate (10µM). Mitochondria isolated from rat brains were submitted to oxidative stress and treated with ETAC. RESULTS: Only the EHAC extract reduced cell viability by 30% after 72h of treatment. Morphological analyses by Immunofluorescence showed positive staining for glutamine synthetase, ß-III tubulin, GFAP and IBA1 similar to control cultures, indicating a better preservation of astrocytes, neurons and microglia, after excitotoxic damage induced by glutamate in cerebellar cultures treated with the extracts. The ETAC extract also protected mitochondria isolated from rat brains from oxidative stress, reducing the swelling, dissipation of the membrane potential, ROS production and calcium influx. CONCLUSION: Thus, this study suggests that the seed extracts from A. Cearensis exhibit neuroprotective potential against oxidative stress and excitotoxicity induced by glutamate and can be considered a potential therapeutic agent in the treatment of neurodegenerative diseases.

The flavonoid rutin modulates microglial/macrophage activation to a CD150/CD206 M2 phenotype.

Rutin is a glycosylated flavonoid present in many fruits and plants that has been demonstrated to have anti-inflammatory and antioxidant properties. However, little is known about the mechanisms underlying microglial activation and its effects on the regulation of cytokines and chemokines associated with inflammatory responses in the central nervous system. In this study we examined the effect of rutin on resting or lipopolysaccharide (LPS)-stimulated microglia and characterized their modulation to an activated M1 phenotype or an alternatively activated M2 phenotype. Microglial cells were treated with rutin (1-100 µM); alternatively, microglial cells were stimulated with LPS and the cells were then treated with rutin (50 µM). The results revealed that rutin treatment was not toxic to microglial cells and induced a dose-dependent increase in microglial proliferation associated with changes in morphology after 24 h of treatment. Rutin also induced microglial activation characterized by an increase in OX-42 positive cells and a large proportion of cells with a CD150/CD206-positive M2 phenotype. Rutin also induced a decrease in the mRNA levels of TNF, IL1ß, IL6 and iNOS, reduced the production of IL6, TNF, and nitric oxide, and increased production of the M2 regulatory cytokine IL10 and arginase. Rutin also significantly inhibited the LPS-induced expression of PTGS2, IL18 and TGFß mRNA. These findings show that rutin has the ability to promote microglial proliferation and induces microglial polarization to the M2 profile when cells are stimulated with LPS. These results point this flavonoid as a possible alternative in the treatment or prevention of neurodegenerative disorders.