ABSTRACT
Abstract Previous pre-clinical studies demonstrated that a valepotriates enriched fraction from Valeriana glechomifolia F.G. Mey., Caprifoliaceae, was effective against lipopolysaccharide from Escherichia coli (LPS)-induced sickness behavior as well as significantly decreased the cortical expression of pro inflammatory cytokines interleukin-1β and tumor necrosis factor-α. Other studies revealed anti-inflammatory properties of V. wallichii and V. amurensis. These findings open up new perspectives for Valeriana genus pharmacology, once it has been commonly associated to sedative and anxiolytic properties. The aim of this study was to investigate the antichemotactic, antinociptive and anti-inflammatory activities of a valepotriate-enriched fraction obtained from aerial and subterranean parts of V. glechomifolia submitted to supercritical CO2 extraction. The biological activities were assessed by means of formalin test in CF1 mice and Wistar rat's leukocytes migration assay (modified Boyden chamber method). Valepotriate-enriched fraction (1, 10 and 30 mg/kg, p.o.) inhibited the nociceptive behavior in the late phase of the formalin test in a dose dependent manner. The effect of the valepotriate-enriched fraction highest dose was comparable with that of diclofenac 50 mg/kg (p.o.). Valepotriate-enriched fraction (0.1-1 µg/ml) inhibited the leukocyte migration induced by lipopolysaccharide from Escherichia coli in a concentration dependent manner. This antichemotatic effect was comparable with that of indomethacin (0.1-1 µg/ml) and better than diclofenac (1 µg/ml) effect. This study demonstrated for the first time that a valepotriate-enriched fraction obtained from V. glechomifolia display a peripheral anti-inflammatory like activity.
ABSTRACT
Abstract Aiming to investigate new therapeutic agents with fewer side effects, the number of studies about natural products has increased. Phenolic compounds comprise a well-studied class of abundant plant-derived compounds, whose anti-inflammatory activity has been described. Isoflavones are phenolic compounds that occur mainly in the Leguminosae family, and can be found in many species, such as Trifolium riograndense Burkart, Leguminosae (clover). In this study an HPLC method was used to determine and quantify four isoflavones (genistein, daidzein, formononetin, and biochanin A) in hydrolyzed leaf, flower, stolon, and root extracts of T. riograndense. In vivo anti-inflammatory activity was investigated using the rat paw edema method and in vitro chemotaxis model with a dry extract from the leaves, which had the highest amount of isoflavones. The major isoflavone found in all parts of the plant was formononetin. The chemotaxis assay revealed that the different concentrations (0.2-50 µg/ml) of the dry extract significantly inhibited neutrophil migration in a concentration-dependent manner (more than 90%). In the rat paw edema test, oral administration of clover extract 100 mg/kg was able to significantly inhibit the edema formation induced by carrageenan. In conclusion, chemical analyses showed that Trifolium riograndense is a plant rich in isoflavones and a new interesting option as isoflavone source. The results of the biological tests taken together show that the extract of T. riograndense has anti-inflammatory effect in rodents.
ABSTRACT
Background The skin secretions of toads of the family Bufonidae contain biogenic amines, alkaloids, steroids (bufotoxins), bufodienolides (bufogenin), peptides and proteins. The poison of Rhinella schneideri, formerly classified as Bufo paracnemis, presents components that act on different biological systems, including the complement system. The aim of this study was to isolate and examine the activity ofRhinella schneideri poison (RsP) components on the complement system.Methods The components active on the complement system were purified in three chromatographic steps, using a combination of cation-exchange, anion-exchange and gel filtration chromatography. The resulting fractions were analyzed by SDS-PAGE and screened for their activity in the hemolytic assay of the classical/lectin complement pathways. Fractions active on the complement system were also assessed for their ability to generate C3 fragments evaluated by two dimensional immunoelectrophoresis assay, C3a and C5a by neutrophil chemotaxis assay and SC5b-9 complex by ELISA assay.Results The fractionation protocol was able to isolate the component S5 from theRsP, as demonstrated by SDS-PAGE and the RP-FPLC profile. S5 is a protein of about 6000 Da, while S2 presents components of higher molecular mass (40,000 to 50,000 Da). Fractions S2 and S5 attenuated the hemolytic activity of the classical/lectin pathways after preincubation with normal human serum. Both components stimulated complement-dependent neutrophil chemotaxis and the production of C3 fragments, as shown by two-dimensional immunoelectrophoresis. S2 showed a higher capacity to generate the SC5b- 9 complex than the other fractions. This action was observed after the exposure of normal human serum to the fractions.Conclusions This is the first study to examine the activity of RsP components on the complement system. Fractions S2 and S5 reduced the complement hemolytic activity, stimulated complement-dependent neutrophil chemotaxis and stimulated the production of C3 fragments, indicating that they were able to activate the complement cascade. Furthermore, fraction S2 was also able to generate the SC5b-9 complex. These components may be useful tools for studying dysfunction of the complement cascade.(AU)
Subject(s)
Animals , Poisons , Biological Products , Bufonidae , ChemotaxisABSTRACT
Background The skin secretions of toads of the family Bufonidae contain biogenic amines, alkaloids, steroids (bufotoxins), bufodienolides (bufogenin), peptides and proteins. The poison of Rhinella schneideri, formerly classified as Bufo paracnemis, presents components that act on different biological systems, including the complement system. The aim of this study was to isolate and examine the activity ofRhinella schneideri poison (RsP) components on the complement system.Methods The components active on the complement system were purified in three chromatographic steps, using a combination of cation-exchange, anion-exchange and gel filtration chromatography. The resulting fractions were analyzed by SDS-PAGE and screened for their activity in the hemolytic assay of the classical/lectin complement pathways. Fractions active on the complement system were also assessed for their ability to generate C3 fragments evaluated by two dimensional immunoelectrophoresis assay, C3a and C5a by neutrophil chemotaxis assay and SC5b-9 complex by ELISA assay.Results The fractionation protocol was able to isolate the component S5 from theRsP, as demonstrated by SDS-PAGE and the RP-FPLC profile. S5 is a protein of about 6000 Da, while S2 presents components of higher molecular mass (40,000 to 50,000 Da). Fractions S2 and S5 attenuated the hemolytic activity of the classical/lectin pathways after preincubation with normal human serum. Both components stimulated complement-dependent neutrophil chemotaxis and the production of C3 fragments, as shown by two-dimensional immunoelectrophoresis. S2 showed a higher capacity to generate the SC5b- 9 complex than the other fractions. This action was observed after the exposure of normal human serum to the fractions.Conclusions This is the first study to examine the activity of RsP components on the complement system. Fractions S2 and S5 reduced the complement hemolytic activity, stimulated complement-dependent neutrophil chemotaxis and stimulated the production of C3 fragments, indicating that they were able to activate the complement cascade. Furthermore, fraction S2 was also able to generate the SC5b-9 complex. These components may be useful tools for studying dysfunction of the complement cascade.