Brasiliensis Extracts Research Articles

Purinergic agents of hydroalcoholic Agaricus brasiliensis extracts: identification, quantification and biological assays

In the present work the effects of an hydroalcoholic extract of Agaricus brasiliensis (formerly known as A. blazei) on metabolic parameters in the perfused rat liver have been examined with emphasis on its content on nucleotides and nucleosides, which act as purinergic agents. Several nucleosides and nucleotides were identified in the A. brasiliensis extract. Consistently, the extract is active on several liver functions in a relatively complex way. It increased perfusion pressure, oxygen consumption, glycogenolysis, glycolysis, ureogenesis, gluconeogenesis, and shifted the redox state of the cytosolic NAD-NADH couple toward a more reduced state. A significant part of these effects seems to be the result of purinergic action, as indicated mainly by experiments with inhibitors and antagonists: pressure changes, glycogenolysis control (glucose and lactate release) and the redox state changes. Another set of phenomena, namely the increased gluconeogenesis and ureogenesis and especially the ubiquitous stimulation of oxygen consumption, are more likely the consequence of metabolic transformation of several substrates contained within the extract, especially amino acids. The results of the present work have implications for both the consumer of A. brasiliensis as a functional and nutraceutic food and for the experimentator interested in the physiologic and pharmacologic effects of the mushroom. It seems apparent that consumption of A. brasiliensis represents not only the ingestion of metabolic precursors, but also the ingestion of substances that, even at low concentrations, can exert important signalling functions not only in the liver but in the organism as a whole.

Effects ofAgaricus brasiliensismushroom in Walker-256 tumor-bearing rats

Agaricus brasiliensis is a mushroom native to São Paulo State, Brazil, that is studied for its medicinal proprieties. This work aimed to investigate the antitumoral activity of A. brasiliensis extracts and pure powdered basidiocarp preparation using Walker-256 (W256) tumor-bearing rats, a model for cancer-related cachexia studies. The rats were treated for 14 days by gavage (136 mg/kg) and at the end of the experiment tumors were collected to calculate mass and volume. Blood was collected for determination of plasma glucose, albumin, alanine aminotransferase (ALT), and aspartate aminotransferase (AST). Hepatic and tumor enzymes indicating oxidative stress were also evaluated. The results showed that all 4 treatments (pure powdered basidiocarp and aqueous, acid, and alkaline extracts) significantly reduced tumor size and promoted gain in body weight. Plasmatic analysis showed a reduction in AST level and increased glycemia in the treated rats. Pure basidiocarp preparations improved the liver catalase and superoxide dismutase activity, but did not change the glutathione S-transferase activity. The data collected from the W256 tumor-bearing rats revealed the beneficial effects of A. brasiliensis in tumor treatment, mainly related to cachexia. The benefits can be partly related to antioxidant activity and to reduction of weight loss and tumor growth.

Matrix metalloproteinases with gelatinolytic activity induced by Paracoccidioides brasiliensis infection

Matrix metalloproteinases (MMPs) modulate extracellular matrix turnover, inflammation and immunity. We studied MMP-9 and MMP-2 in experimental paracoccidioidomycosis. At 15 and 120 days after infection (DAI) with virulent Paracoccidioides brasiliensis, MMP-9 was positive by immunohistochemistry in multinucleated giant cells, in mononuclear cells with macrophage and lymphocyte morphologies and also in fungal cells in the lesions of susceptible and resistant mice. Using gelatin zymography, pro- and active MMP-9 and active MMP-2 were detected in all infected mice, but not in controls. Gelatinolytic activity was not observed in P. brasiliensis extracts. Semiquantitative analysis of gelatinolytic activities revealed weak or absent MMP-2 and strong MMP-9 activity in both mouse strains at 15 DAI, declining at 120 DAI. Avirulent P. brasiliensis-infected mice had residual lesions with MMP-9-positive pseudoxantomatous macrophages, but no gelatinase activity at 120 DAI. Our findings demonstrate the induction of MMPs, particularly MMP-9, in experimental paracoccidioidomycosis, suggesting a possible influence in the pattern of granulomas and in fungal dissemination.

Cytotoxic, mutagenic and antimutagenic screening of Arenosclera brasiliensis acetone and ethanol extracts

The marine environment is a rich source of biologically active compounds with pharmacological properties. Marine organisms often produce secondary metabolites with structural features different from those produced by terrestrial ones, and the Phylum Porifera seems to be one of the most productive in this sense. This study was undertaken to provide data on mutagenic and antimutagenic activities from an acetone (Areac) and an ethanol (Areet) extract obtained from Arenosclera brasiliensis, an endemic Brazilian sponge. A qualitative Salmonella reverse mutation test was performed with the TA97, TA98, TA100, and TA102 strains by incubating cells with Areac and Areet in the presence and absence of a known mutagen. A cytotoxic evaluation of the extracts was also performed. A. brasiliensis did not display any mutagenic activity, but Areac showed significant toxicity against test strains. In the antimutagenic assay, a reduction in the number of his+ revertants was observed for the TA97, TA100 and TA102 strains treated with Areac when compared to the positive controls. Areet treatment showed protective activity against DNA lesions only for the TA100. These results are in agreement with those obtained previously with other A. brasiliensis extracts, suggesting an antimutagenic activity.

Evaluation of the genotoxic potential of the Hypericum brasiliense (Guttiferae) extract in mammalian cell system in vivo

Plants of the genus Hypericum, long used in folk medicine, contain active compounds which present, anti-septic, diuretic, digestive, expectorant, vermifugal, anti-depressive and other properties. The possible clastogenic effect of a H. brasiliense extract was tested in vivo on the bone marrow cells of Wistar rats. The extract was administered by gavage at doses of 50, 150 and 300 mg/kg body weight. Experimental and control animals were submitted to euthanasia 24 h after the treatment for micronucleus (MN) and chromosome preparations. H. brasiliense extract did not induce statistically significant increases in the average numbers of MN or chromosome aberrations in the test systems employed.

Cytotoxic and neurotoxic activities in extracts of marine sponges (Porifera) from southeastern Brazilian coast

This work reports the results of a screening program based on marine sponge extracts from the southeastern Brazilian coast, covering cytotoxic and neurotoxic activities. Polar and non-polar extracts of 24 sponge species collected by scuba diving in rocky shores, from 1996 to 2000, were screened for haemolytic, cytotoxic and neurotoxic activities. Fifty-four percent (13/24) of the sponge extracts tested exhibited from median to high toxicity in at least one of the toxicity bioassays performed. Amphimedon sp. and Arenosclera brasiliensis Muricy and Ribeiro, 1999 induced haemolysis in mice erythrocytes at small concentrations. Aaptos sp. and Geodia corticostylifera Hajdu, Muricy, Custodio, Russo and Peixinho, 1992 extracts lysed the sea-urchin eggs, while Axinella aff. corrugata George and Wilson, 1919, Mycale laxissima Duchassaing and Michelotti, 1864, A. brasiliensis and Raspailia elegans Bourm-Esnauls, 1973, inhibited mitosis and its development. The extracts of G. gibberosa Lamarck, 1815 and Stelletta sp. showed specific neurotoxic activity, while G. corticostylifera and A. brasiliensis extracts induced blockage of action potential conduction in crustacean nerve, maybe due to their lytic properties.

Antiinflammatory activity and acute toxicity (LD50) of the juice of Kalanchoe brasiliensis (Comb.) leaves picked before and during blooming.

Kalanchoe brasiliensis Comb. (Cassulaceae) extracts from leaves picked before and during plant blooming (extracts 1 and 2, respectively) were tested for their antiinflammatory effect on carrageenin-induced rat paw oedema and for acute toxicity (LD50). Oral doses of 0.25, 0.5 and 1.0 g/kg of extract 1 significantly inhibited the paw oedema during the first 4 h after injection of 2% carrageenin, while oral doses of 0.5, 1.0 and 2.0 g/kg of extract 2 had no inhibitory activity on the paw oedema induced by carrageenin. The results indicate an antiinflammatory effect of extract 1 and a proinflammatory effect of extract 2. K. brasiliensis extracts 1 and 2 presented no acute toxicity on mice at the doses of 0.25 to 5 g/kg administered intraperitoneally.

Allergic contact dermatitis caused by lithraea molleoides and Lithraea brasiliensis: Identification and characterization of the responsible allergens

Background : Allergic contact dermatitis caused by species of Lithraea genus (Anacardiaceae) is frequent in South America. Nevertheless, it has been scarcely reported in the literature, hitherto the responsible allergens have not been studied in some species. Objective : The purpose of this study was to identify and characterize the allergenic compounds of Lithraea molleoides and brasiliensis, and to investigate the existence of cross-reactions with Toxicodendron allergens. Methods : Twenty-seven South American subjects (17 with previous Lithraea dermatitis and 10 controls without any plant dermatitis) and four North American subjects who are highly sensitive to poison oak were tested with both purified Lithraea molleoides and brasiliensis extracts and poison oak urushiol. Lithraea extracts were analyzed by gas liquid chromatography (GLC) and gas chromatography-mass spectrometry (GC-MS). Results : All 17 Lithraea-sensitive subjects reacted to poison oak urushiol and 13 of them also reacted to Lithraea molleoides and/or brasiliensis extracts. All 4 poison oak sensitive subjects reacted to poison oak urushiol and to Lithraea extracts. In both groups of sensitive subjects, the responses to poison oak urushiol were stronger and occurred at lower concentration than those to Lithraea extracts. The allergenic fraction in both Lithraea species consisted of: 3-pentadecylcatechol, 3-pentadecenylcatechol, 3-heptadecenylcatechol and 3-hepta-dec-dienilcatechol. Conclusion : We concluded that Lithraea molleoides and brasiliensis allergens are closely related to urushiol, although their eliciting potential seems to be lower in comparison with poison oak urushiol, even for Lithraea-sensitive subjects.

Characterization of the cellular antigens of Paracoccidioides brasiliensis yeast form

Antigenic components of the yeast extract of Paracoccidioides brasiliensis Linder 2511 cultured for 3, 8, 20, 30, and 60 days were examined by the Western blot (immunoblot) technique. The 3-day extract was chosen for characterization of the antigenic components because its stability did not vary with time and it contained all antigens identified by patient sera. Antibodies to cross-reacting antigens of P. brasiliensis extracts were detected in sera from patients with histoplasmosis, candidiasis, and aspergillosis. The 58-, 57-, 21-, and 16-kilodalton (kDa) antigens were specific for P. brasiliensis, while the 48- and 45-kDa antigens were specific for paracoccidioidomycosis. The Western blot technique is a useful tool for the diagnosis of disease and revealed heterogeneity in the responses of patient sera. The combination of the 58-, 57-, and 45-kDa proteins confirmed a diagnosis of paracoccidioidomycosis (87% of the cases).

Suppression of IgE antibody production in SJL mice. III. Characterization of a suppressor substance extracted from normal SJL spleen cells.

SJL mice were immunized with 1 microng dinitrophenylated keyhole limpet hemocyanin in 1 mg Al(OH)3. The mice were infected 21 days later with 750 third stage larvae of Nippostrongylus brasiliensis. On day 35, 14 days after infection, they were injected with 1 microng DNP-N, brasiliensis extract (Nb) in 1 mg Al(OH)3. In order to obtain high titer and persistent anti-DNP IgE antibody the mice were irradiated (540 R) 1 day after injection of DNP-Nb. Suppression of anti-DNP IgE antibody production was induced by spleen cells from normal SJL mice. Suppression of IgE antibody response is also obtained by an extract from normal SJL spleen cells. The suppressor substance from normal SJL spleen cell extract is a heat-labile protein, and is not absorbed by anti-mouse immunoglobulin. The mol wt of this substance is larger than 300,000 daltons as determined by gel filtration on Sephadex G-200, but after ultracentifugation, the supernate still has suppressive activity on IgE antibody production.

Tolerizing Effect of DNP-Ficoll on IgE Antibody Production

A/J and DBA/1 mice were infected with 750 third-stage larvae of Nippostrongylus brasiliensis and immunized with 1 mug dinitrophenylated N. brasiliensis extract (DNP-Nb) with 1 mg Al(OH)3 to produce high titers of anti-hapten IgG1 and IgE antibody. Partial tolerance to the production of anti-hapten IgG1 and IgE antibody could be induced by DNP-Ficoll from 5 weeks before to 1 week after the DNP-Nb immunization. The tolerized state persisted through the duration of the experiments. However, no tolerizing effect could be demonstrated on secondary antihapten IgE antibody production induced by DNP-Nb. Moreover, DNP-Ficoll failed to evoke anti-hapten IgG1 or IgE antibody production.

Effect of Nippostrongylus brasiliensis infection on anti-hapten IgE antibody response in the mouse : I. Induction of carrier specific helper cells

Inoculation of infective larvae of Nippostrongylus brasiliensis into A/J, BALB/c, and SJL mice primed intraperitoneally (ip) 3 weeks before infection with 1 μg of dinitrophenylated keyhole limpet hemocyanin (DNP-KLH) mixed with 1 mg Al(OH) 3 induced a carrier effect on anti-DNP IgE and IgG 1 antibody responses when the experimental mice were secondarily immunized with an ip injection of 1 μg of DNP-coupled N. brasiliensis extract (DNP-Nb) plus alum 2 weeks after infection. The magnitude of the hapten specific antibody response did not correlate rigidly with the number of larvae in the inoculum. Thus, a dose of 100 larvae was as effective in inducing the carrier effect as a dose of 800 larvae. Kinetic studies in A/J and BALB/c mice revealed that the anti-DNP IgE antibody response reached a maximum titer 7 days after the secondary immunization. These studies also showed that the enhanced IgE antibody response persisted for more than 40 days, while the response in all control groups terminated prior to that time. Using the adoptive transfer system, it was demonstrated that lymphoid cells obtained from the spleens or the mesenteric lymph nodes of infected mice cooperated with DNP-KLH primed cells to produce hapten specific IgE and IgG, antibodies when the challenge was made with DNP-Nb but not when it was made with 1 μg DNP-ovalbumin, clearly indicating carrier specificity. The helper activity of the cells obtained from infected mice was completely abolished or greatly reduced by the in vitro treatment with anti-θ serum and complement. The helper cells with maximum activity were present as early as 14 days after inoculation. The level of helper activity gradually decreased after 14 days. The results indicate that N. brasiliensis infection is effective in inducing carrier specific helper cells of thymic origin (T cells) in anti-DNP antibody responses. These results confirm those obtained by other investigators and add the new observation that N. brasiliensis infection elicits special helper T cells which induce an enhancement as well as a prolongation of anti-DNP IgE antibody response.