UPLC-QTOF-MS/MS-based metabolomic approach and gastroprotective effect of two chemotypes of Egletes viscosa (L.) less. against ethanol-induced gastric ulcer in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Egletes viscosa (L.) (macela) is a native wild herb that can be found in different states of northeastern Brazil. The infusions of its flower buds are traditionally used for the treatment of gastrointestinal disorders. E. viscosa possesses two chemotypes (named A and B), distinguishable by the composition of the essential oil from the flower buds. Although there are previous studies of the gastroprotective effect of the isolated constituents of E. viscosa, its infusions have not been investigated yet. AIM OF THE STUDY: The present study aimed to evaluate and compare the chemical composition and the gastroprotective effect of flower bud infusions of E. viscosa from chemotype A (EVCA) and chemotype B (EVCB). MATERIALS AND METHODS: Sixteen infusions were brewed with flower buds according to the traditional preparation mode and were analyzed through a UPLC-QTOF-MS/MS based metabolomic approach for determination of their metabolic fingerprints and quantification of bioactive compounds. Afterward, these data were analyzed by chemometric methods (OPLS-DA) for discrimination of the two chemotypes. Additionally, infusions of EVCA and EVCB (50, 100 and 200 mg/kg, p.o.) were evaluated on gastric ulcers induced by absolute ethanol (96%, 0.2 mL, p.o.) in mice. To elucidate the gastroprotective mechanisms, the effect of EVCA and EVCB on gastric acid secretion and gastric wall mucus was determined and the role of TRPV1 channels, prostaglandins, nitric oxide and KATP channels were assessed. Moreover, the oxidative stress-related parameters and the histological aspects of the stomach tissue were analyzed. RESULTS: The chemotypes can be discriminated from each other using UPLC-QTOF-MS/MS chemical fingerprints. Both chemotypes presented similar chemical compositions, consisting basically of caffeic acid derivatives, flavonoids and diterpenes. The quantification of bioactive compounds demonstrated that chemotype A possesses more ternatin, tanabalin and centipedic than chemotype B. EVCA and EVCB (50, 100 and 200 mg/kg, p.o.) significantly decreased the severity of ethanol-induced gastric lesions, as shown by a reduction in histological alterations and leucocyte infiltration in gastric tissue. The gastroprotective mechanism of both infusions involves an antioxidant effect, maintenance of gastric mucus and reduction gastric secretion. Stimulation of endogenous prostaglandins and nitric oxide release, activation of TRPV1 channels, and KATP channels are also involved in the gastroprotection of the infusions. CONCLUSION: The gastroprotective effect of EVCA and EVCB was equivalent and mediated through antioxidant and antisecretory actions, including the activation of TRPV1 receptors, stimulation of endogenous prostaglandins and nitric oxide, and opening of KATP channels. The presence of caffeic acid derivatives, flavonoids and diterpenes in both infusions is involved in mediating this protective effect. Our findings support the traditional use of infusions of E. viscosa for gastric disorders regardless of the chemotype.

Anti-inflammatory withajardins from the leaves of Athenaea velutina.

Withajardins, uncommon modified withanolide-type steroids, have been isolated exclusively from plants of the Solanaceae family so far. Two undescribed withajardins and the known tuboanosigenin were isolated from the hexane/EtOAc 1:1 extract from Athenaea velutina leaves. Their structures were established by an extensive analysis of 1D and 2D-NMR and HRMS data. The absolute configuration was determined by X-ray diffraction (withajardin L and tuboanosigenin) and circular dichroism (CD) analyses (withajardin M). The anti-inflammatory activity of compounds was evaluated through the inhibition of the lipopolysaccharide (LPS)-induced nitric oxide (NO), TNF-α, and IL-6 release in RAW264.7 cells. The cell viability effects to RAW 264.7 cells showed IC50 values of 74.4-354.4 µM. The compounds attenuated LPS-induced release of NO and decreased pro-inflammatory cytokines TNF-α and IL-6 in RAW264.7 cells.

Antimicrobial activity and chemical characterization of the bark decoction of cumaru stem / Atividade antimicrobiana e caracterização química do decocto da casca do caule de cumaru

ABSTRACT: The plant, Amburana cearensis A. C. Smith (Fabaceae), commonly called cumaru, is widespread in the Caatinga cearense, a less known ecosystem in Brazil. A. cearensis is rich in several compounds like protocatechuic acid, tannins, coumarin, flavonoids and phenolic heterosides, such as amburosides A and B, that have been isolated. The aim of this study was to determine the antimicrobial potential and draw the chemical profile of the distinct characteristics of A. cearensis stem bark decoction, for its possible potential as a food conservation agent. The chemical compounds were characterized by one- and two-dimensional 1H and 13C NMR analyses and Liquid Chromatography-Mass Spectrometry (LCMS). The compounds of coumarin, amburosides A and B, and glycosylated (Z)-o-coumaric acid. Using the plaque microdilution technique, the antimicrobial action was tested on Escherichia coli, Salmonella Enteritidis, Pseudomonas aeruginosa, Staphylococcus aureus and Listeria monocytogenes. The decoction demonstrated antimicrobial activity on Gram-positive bacteria. This was encouraging because natural antimicrobials are beneficial for food production, as they can inhibit the pathogenic microorganisms and boost the quality of hygiene and cleanliness.

RESUMO: Amburana cearensis A. C. Smith (Fabaceae) é uma planta comum na Caatinga cearense, onde é popularmente conhecida como cumaru. Vários compostos têm sido isolados de A. cearensis, incluindo ácido protocatecúico, taninos, cumarina, flavonóides e heterosídeos fenólicos, como por exemplo os amburosídeos A e B. O objetivo desse estudo foi avaliar o potencial antimicrobiano e caracterizar o perfil químico do decocto da casca do caule de A. cearensis, visando a sua possível utilização na conservação de alimentos. A caracterização dos compostos químicos foi realizada pelas análises de RMN uni e bidimensionais de 1H e 13C, e cromatografia líquida acoplada à espectrometria de massa. Foram identificados a cumarina, os amburosídeos A e B, e o ácido (Z)-o-cumárico glicosilado. A atividade antimicrobiana foi realizada pela metodologia de microdiluição em placa sobre Escherichia coli, Salmonella Enteritidis, Pseudomonas aeruginosa, Staphylococcus aureus e Listeria monocytogenes. O decocto mostrou atividade antimicrobiana sobre bactérias Gram-positivas. Antimicrobianos naturais podem oferecer vantagens para a produção de alimentos, inibindo microorganismos patogênicos e melhorando a qualidade higiênico-sanitária.

Development of a method for quantitative determination of the cytotoxic agent piplartine (piperlongumine) in multiple skin layers.

This study reports the development of a simple and reproducible method, with high rates of recovery, to extract the cytotoxic agent piplartine from skin layers, and a sensitive and rapid UV-HPLC method for its quantification. Considering the potential of piplartine for topical treatment of skin cancer, this method may find application for formulation development and pharmacokinetics studies to assess cutaneous bioavailability. Porcine skin was employed as a model for human tissue. Piplartine was extracted from the stratum corneum (SC) and remaining viable skin layers (VS) using methanol, vortex homogenization and bath sonication, and subsequently assayed by HPLC using a C18 column, and 1:1 (v/v) acetonitrile-water (adjusted to pH 4.0 with acetic acid 0.1%) as mobile phase. The quantification limit of piplartine was 0.2 µg/mL (0.6 µm), and the assay was linear up to 5 µg/mL (15.8 µm), with within-day and between-days assay coefficients of variation and relative errors <15%. Piplartine recovery from SC and VS varied from 86 to 96%. The method was suitable to assay samples from skin penetration studies, enabling detection of differences in cutaneous delivery in different skin compartments resulting from treatment with various formulations and time periods.

Gingerol suppresses sepsis-induced acute kidney injury by modulating methylsulfonylmethane and dimethylamine production.

Acute kidney injury (AKI) and metabolic dysfunction are critical complications in sepsis syndrome; however, their pathophysiological mechanisms remain poorly understood. Therefore, we evaluated whether the pharmacological properties of 6-gingerol (6G) and 10-gingerol (10G) could modulate AKI and metabolic disruption in a rat model of sepsis (faecal peritonitis). Animals from the sham and AKI groups were intraperitoneally injected with 6G or 10G (25 mg/kg). Septic AKI decreased creatinine clearance and renal antioxidant activity, but enhanced oxidative stress and the renal mRNA levels of tumour necrosis factor-α, interleukin-1ß, and transforming growth factor-ß. Both phenol compounds repaired kidney function through antioxidant activity related to decreased oxidative/nitrosative stress and proinflammatory cytokines. Metabolomics analysis indicated different metabolic profiles for the sham surgery group, caecal ligation and puncture model alone group, and sepsis groups treated with gingerols. 1H nuclear magnetic resonance analysis detected important increases in urinary creatine, allantoin, and dimethylglycine levels in septic rats. However, dimethylamine and methylsulfonylmethane metabolites were more frequently detected in septic animals treated with 6G or 10G, and were associated with increased survival of septic animals. Gingerols attenuated septic AKI by decreasing renal disturbances, oxidative stress, and inflammatory response through a mechanism possibly correlated with increased production of dimethylamine and methylsulfonylmethane.

The anti-inflammatory effects of N-methyl-(2S,4R)-trans-4-hydroxy-l-proline from Syderoxylon obtusifolium are related to its inhibition of TNF-alpha and inflammatory enzymes.

BACKGROUND: Sideroxylon obtusifolium (Roem. & Schult.) T.D. Penn., Sapotaceae family, is a medicinal species native to the Brazilian Northeastern region. The plant is popularly used as an anti-inflammatory and hypoglycemic. PURPOSE: To evaluate the anti-inflammatory properties of the N-methyl-(2S,4R)-trans-4-hydroxy-l-proline (NMP) from S. obtusifolium leaves in models of inflammation and to clarify its action mechanisms. METHODS: Male Swiss mice were distributed intocontrols and groups treated with NMP (25, 50 and 100mg/kg, p.o.), indomethacin or morphine (reference drugs). The animals were subjected to the formalin, carrageenan-induced edema and peritonitis tests. Furthermore, peritoneal lavage and slices from edematous paws were used for histological and immunohistochemical (iNOS, TNF-alpha, COX-2 and NF-kB) assays. RESULTS: Decreases in licking time, in the 1st and mainly in the 2nd phases of the formalin test, were shown after NMP treatments. In addition, decreases (around 50%) in paw edema were noticed at the 3rd h. The HE staining of paw slices demonstrated a complete reversion of the increased PMN cell numberafter NMP treatment. Similarly, decreases higher than 70% were also demonstrated in PMN cells, in the peritoneal fluid. Furthermore, NMP significantly decreased iNOS, TNF-alpha, COX-2 and NF-kB immunoreactivities. CONCLUSIONS: We showed that S. obtusifolium presents a potent anti-inflammatory activity, due to the presence of the N-methyl-(2S,4R)-trans-4-hydroxy-l-proline(NMP) in the plant extract. This action is related to the inhibition by NMP of TNF-alpha and inflammatory enzymes.

Fraction of Auxemma oncocalyx and Oncocalyxone A Affects the In Vitro Survival and Development of Caprine Preantral Follicles Enclosed in Ovarian Cortical Tissue.

BACKGROUND: Auxemma oncocalyx and its main component oncocalyxone A (onco A) have a high level of antioxidant and antitumor activity, but there are no studies on the action of both of these drugs regarding folliculogenesis. MATERIAL AND METHODS: Caprine ovarian tissue fragments were fixed (non-cultured control) or cultured for 1 or 7 days in α-MEM+ alone (cultured control) or supplemented with dimethyl sulfoxide (DMSO; 20% v/v), bone morphogenetic protein 15 (BMP-15; 100 ng/ml), doxorubicin (DXR; 0.3 g/ml), or different concentrations of A. oncocalyx (1.2, 12, or 34 g/ml) or onco A (1, 10, or 30 g/ml). We analyzed for follicular morphology and growth, apoptosis (terminal deoxynucleotidyl transferase dUTP-biotin nick end labeling (TUNEL) assay), and cell proliferation (silver staining of argyrophilic nucleolus organizer regions (AgNOR) and test for proliferating cell nuclear antigen (PCNA)). RESULTS: A. oncocalyx and onco A (in a concentration-dependent manner) and DXR decreased (P < 0.05) the number of morphologically normal follicles, with no effect (P > 0.05) on follicular growth. A. oncocalyx reduced (P < 0.05) the percentage of normal follicles compared to onco A, whereas DXR, A. oncocalyx 1.2 g/ml, and onco A 1 g/ml increased (P < 0.05) the percentage of TUNEL-positive follicles. DXR decreased (P < 0.05) the number of nucleolus organizer regions. CONCLUSION: A. oncocalyx and onco A affected the in vitro caprine folliculogenesis in a concentration-dependent manner. Onco A (1 g/ml) has a less harmful effect than DXR on goat preantral follicle survival.

Pharmacognostical Analysis and Protective Effect of Standardized Extract and Rizonic Acid from Erythrina velutina against 6-Hydroxydopamine-Induced Neurotoxicity in SH-SY5Y Cells.

BACKGROUND: Erythrina velutina is a tree common in the northeast of Brazil extensively used by traditional medicine for the treatment of central nervous system disorders. OBJECTIVE: To develop a standardized ethanol extract of E. velutina (EEEV) and to investigate the neuroprotective potential of the extract and rizonic acid (RA) from E. velutina on neuronal cells. MATERIALS AND METHODS: The plant drug of E. velutina previously characterized was used for the production of EEEV. Three methods were evaluated in order to obtain an extract with higher content of phenols. The neuroprotective effect of standardized EEEV (HPLC-PDA) and RA was investigated on SH-SY5Y cell exposure to the neurotoxin 6-hydroxydopamine (6-OHDA). RESULTS: The powder of the plant drug was classified as moderately coarse and several quality control parameters were determined. EEEV produced by percolation gave the highest phenol content when related to others extractive methods, and its HPLC-PDA analysis allowed to identify four flavonoids and RA, some reported for the first time for the species. EEEV and RA reduced significantly the neurotoxicity induced by 6-OHDA in SH-SY5Y cells determined by the MTT assay and the nitrite concentration. EEEV also showed a free radical scavenging activity. CONCLUSION: This is the first pharmacological study about E. velutina which used a controlled standardized extract since the preparation of the herbal drug. This extract and RA, acting as an antioxidant, presents a neuroprotective effect suggesting that they have potential for future development as a therapeutic agent in neurodegenerative disease as Parkinson. SUMMARY: The powder of Erythrina velutina was classified as moderately coarse and several quality-control parameters were determined.Ethanolic extract from E. velutina (EEEV) produced by percolation gave the highest phenol content when related to others extractive methods and its HPLC-PDA analysis of EEEV allowed to identify four flavonoids and rizonic acid (RA), some reported for the first time for the species.The EEEV and RA reduced significantly the neurotoxicity induced by 6-OHDA in SH-SY5Y cells determined by the MTT assay and the nitrite concentration.The EEEV also showed a free radical scavenging activity. Abbreviations used: ±: More or less, %: Percentage, °C: Degree Celsius, <: Less than, µg: Microgram, µL: Microliter, µM: Micromol, [1D] MNR: One-dimensional nuclear magnetic resonance spectroscopy, [2D] MNR:Two-dimensional nuclear magnetic resonance spectroscopy, 6-OHDA: [6-] Hydroxydopamine. Abs: Absorbance, CFU: Colony forming units, CH2Cl2: Dichloromethane, CHCl3: Chloroform cmCentimeter, DMEM/F12: Dulbecco's Modified Eagle's Medium: Nutrient Mixture F-12. DMSO: Dimethyl sulfoxide, DPPH: 1,1-Diphenyl-2-picrylhydrazyl, EAG: Gallic acid equivalents, EEEV: Ethanolic extract of Erythrina velutina, EtOAc: Ethyl acetate, g: Gram, h: Hour, H2O: Water, HPLC: High-performance liquid chromatography, H REIMS: Hydrogen rapid evaporative ionization mass spectrometry, Kg: Kilogram M: Molar, m: Metro, MeOH: Methanol, mg: Milligram, min: Minute, mL: Milliliter, mm: Millimeter, MTT: Bromide 3 [4,5-dimethylthiazol-2-yl] -2,5-diphenyltetrazolium, N: Normal, NBT: Nitroblue tetrazolium, nm: Nanometer, PDA: Photodiode array detector, TPC: Total polyphenol content, RA: Rizonic acid, RP: Reverse phase, SOD: Superoxide dismutase, v/v: Volume per volume, Vs: Versus W: Watts.

Spirostanol glucosides from the leaves of Cestrum laevigatum L.

Two new steroidal saponins, (25R)-spirost-5-ene-3ß,26ß-diol 3-O-α-L-rhamnopyranosyl-(1 → 4)-α-L-rhamnopyranosyl-(1 → 4)-[(1 → 2)-α-L-rhamnopyranosyl]-ß-D-glucopyranoside (1) and (25R)-spirost-6-ene-3ß,5ß-diol 3-O-α-L-rhamnopyranosyl-(1 → 4)-α-L-rhamnopyranosyl-(1 → 4)-[(1 → 2)-α-L-rhamnopyranosyl]-ß-D-glucopyranoside (2), along with the known diosgenin 3-O-α-L-rhamnopyranosyl-(1 → 4)-α-L-rhamnopyranosyl-(1 → 4)-ß-D-glucopyranoside (3), chonglouoside SL-5 (4) and Paris saponin Pb (5) were isolated from the leaves of Cestrum laevigatum. The structures of the compounds were determined using spectroscopic analyses including HRESI-MS, 1D and 2D NMR data, followed by comparison with data from the literature. Among them, two are particularly unique, compound 1 is the first (6)Δ-spirostanol saponin and compound 2 has an unusual C-26 hydroxyl in the (5)Δ-spirostanol skeleton. Antifungal testing showed a potent activity to formosanin C against Candida albicans and Candida parapsilosis. Evaluation of the cytotoxic activity indicated that compound 1 has a moderate activity against HL-60 and SF-295 cell lines, while compound 2 were active only against HL-60.

Activity of Fabaceae species extracts against fungi and Leishmania: vatacarpan as a novel potent anti-Candida agent

AbstractLeishmaniasis and fungal infection treatment efficacy is limited by toxicity and ever increasing resistance to available drugs, requiring development of alternative compounds. The richness of Cerrado plant antimicrobial secondary metabolites justifies screening of Fabaceae species extracts: Enterolobium ellipticum Benth., Sclerolobium aureum (Tul.) Baill. and Vatairea macrocarpa(Benth.) Ducke, against Leishmania(Leishmania) amazonensis, yeasts and dermatophytes. Among the 26 extracts tested, more than 50% of the total demonstrated significant antifungal activity in comparison to the drug controls (minimal inhibitory concentration 0.12 to ≤31.25 µg/ml). Six extracts capable of complete parasitic growth inhibition had the inhibitory concentration index for 50% values from 9.23 to 78.65 µg/ml. The results led to the selection of the V. macrocarpa ethyl acetate root bark extract for chemical fractionation. This plant, traditionally referred to as angelim-do-cerrado or maleiteira, is used to treat superficial mycoses in Amazonia. A previously unreported pterocarpan vatacarpan together with the known compound musizin was isolated. Vatacarpan demonstrated a minimal inhibitory concentration value of 0.98 µg/ml against Candida albicans ATCC 10231, and thus comparable or superior to fluconazole and amphotericin B. The results add to literature's information the ability of pterocarpans to act as antimicrobial agents.

Vasorelaxant and antihypertensive effects of methanolic fraction of the essential oil of Alpinia zerumbet.

Alpinia zerumbet is used in folk medicine in Brazil to treat hypertension. However, several pathways involved in the mechanism of vasorelaxation are still unclear. This study was designed to verify the antihypertensive effect of the methanolic fraction of the essential oil of A. zerumbet (MFEOAz) and to characterize its mechanism of action. The thoracic aortic rings from the Wistar rats were perfused in the organ chambers filled with Kreb's solution, where the tension of each ring was measured. The antihypertensive effect of MFEOAz was assessed in rats submitted to chronic hypertension by inhibition of nitric oxide synthesis by indirect measurement of blood pressure with indirect tail cuff method. MFEOAz relaxed phenylephrine and KCl-induced contraction of either endothelium-intact or endothelium-denuded rat aortic rings in a concentration-dependent manner. Pre-incubation with MFEOAz (100 and 300 µg/mL) in Ca(2+)-free Krebs solution attenuated phenylephrine- or caffeine-induced contraction. Pre-incubation with L-NAME, ODQ, wortmannin, atropine, indomethacin, catalase, SOD, TEA, 4-aminopyridine, glibenclamide, apamin, charybdotoxin, or iberiotoxin did not affect MFEOAz-induced relaxation. The intragastric administration of MFEOAz induced an antihypertensive effect. MFEOAz it seems inhibited the calcium influx via voltage-operated calcium channels and receptor-operated calcium channels, as well as inhibition of calcium mobilization from intracellular stores.

Structure elucidation and anticancer activity of 7-oxostaurosporine derivatives from the Brazilian endemic tunicate Eudistoma vannamei.

The present study reports the identification of two new staurosporine derivatives, 2-hydroxy-7-oxostaurosporine (1) and 3-hydroxy-7-oxostaurosporine (2), obtained from mid-polar fractions of an aqueous methanol extract of the tunicate Eudistoma vannamei, endemic to the northeast coast of Brazil. The mixture of 1 and 2 displayed IC50 values in the nM range and was up to 14 times more cytotoxic than staurosporine across a panel of tumor cell lines, as evaluated using the MTT assay.

Cytotoxicity of δ-tocotrienols from Kielmeyera coriacea against cancer cell lines.

In the search for new anti-cancer compounds, Brazilian Cerrado plant species have been investigated. The hexane root bark extract of Kielmeyera coriacea lead to a mixture of δ-tocotrienol (1) and its dimer (2). The structures of both compounds 1 and 2 were established based on detailed 1D and 2D NMR and EI-MS analyses. The cytotoxicity of the mixture was tested against four human tumor cell lines in the following cultures: MDA-MB-435 (melanoma), HCT-8 (colon), HL-60 (leukemia), and SF-295 (glioblastoma), and displayed IC(50) values ranging from 8.08 to 23.58µg/mL. Additional assays were performed in order to investigate the mechanism of action of the mixture (1+2) against the human leukemia cell line HL-60. The results suggested that the mixture suppressed leukemia growth and reduced cell survival, triggering both apoptosis and necrosis, depending on the concentration.

Pro-apoptotic activity of lipidic α-amino acids isolated from Protopalythoa variabilis.

Lipidic α-amino acids (LAAs) have been described as non-natural amino acids with long saturated or unsaturated aliphatic chains. In the continuing prospect to discover anticancer agents from marine sources, we have obtained a mixture of two cytotoxic LAAs (1a and 1b) from the zoanthid Protopalythoa variabilis. The anti-proliferative potential of 14 synthetic LAAs and 1a/1b were evaluated on four tumor cell lines (HCT-8, SF-295, MDA-MB-435, and HL-60). Five of the synthetic LAAs showed high percentage of tumor cell inhibition, while 1a/1b completely inhibited tumor cell growth. Additionally, apoptotic effects of 1a/1b were studied on HL-60 cell line. 1a/1b-treated cells showed apoptosis morphology, loss of mitochondrial potential, and DNA fragmentation.

Effects of Copaifera langsdorffii Desf. on ischemia-reperfusion of randomized skin flaps in rats.

BACKGROUND: Copaíba oil is an oleoresin obtained from the Copaiffera langsdorffii genus (Leguminoseae). It is widely used in folk medicine as an antiinflammatory, healing, and antiseptic agent. Comparative pharmacologic studies between different species of copaíba oils are scarce. METHODS: The protective effect of Copaiffera langsdorffii was evaluated on an experimental model of random skin flaps on rat dorsums. RESULTS: Seventy-two Wistar rats (average weight = 216.8 g) were divided randomly into four equal groups (saline control, vehicle control, GT200-Test 1, and GT400-Test 2). A caudally based rectangular flap, 2.5-8.0 cm in size, was elevated on the back of the rat using McFarlane's method. The flap was sutured back into its original place. Copaifera and control drugs (saline and Tween 80) were administered by gavage 24, 12, and 2 h prior to the beginning of the experiment followed by daily doses for the next 7 days. To observe the effects of Copaifera, laboratory analyses included plasma and tissue levels of tiobarbituric acid-reactive substances (TBARS) and reduced glutathione (GSH) and tissue levels of myeloperoxidase (MPO). CONCLUSION: The oil-resin of copaíba presents discrete antilipoperoxidation action, intense antioxidant action, and antiinflammatory activity during the ischemia and reperfusion of randomized cutaneous flaps. The effects of ischemia-reperfusion are complex and substances capable of increasing the tolerance of tissue to those effects by reducing the production or neutralizing the action of free radicals are needed.

Effects of amburoside A and isokaempferide, polyphenols from Amburana cearensis, on rodent inflammatory processes and myeloperoxidase activity in human neutrophils.

The present study evaluated the anti-inflammatory activity of amburoside A (a phenol glucoside) and isokaempferide (a flavonol) isolated from the trunk bark of Amburana cearensis, a medicinal plant used in northeast Brazil for the treatment of asthma. Animals (male Wistar rats or Swiss mice) pre-treated with amburoside A (25 and 50 mg/kg) or isokaempferide (12.5, 25 and 50 mg/kg), orally or intraperitoneally, showed a significant inhibition of the paw oedema induced by carrageenan (1%), prostaglandin E(2) (30 nmol/paw), histamine (200 microg/paw) or serotonin (200 microg/paw). Histological and morphometric evaluations of the rat paw oedema induced by carrageenan showed that amburoside A and isokaempferide also inhibited the accumulation of inflammatory cells. Amburoside A reduced significantly the paw oedema and the increase in vascular permeability induced by dextran, as related to the control group. Similar results were observed with the isokaempferide pre-treatment. Furthermore, amburoside A or isokaempferide inhibited both leucocyte and neutrophil migrations, in mouse peritoneal cavity, after the carrageenan injection. The polyphenols were not cytotoxic and blocked N-formyl-methyl-leucyl-phenylalanine-induced myeloperoxidase release and activity in human neutrophils. In addition, amburoside A and isokaempferide at 50 and 100 microg/ml concentrations reduced significantly the lipopolysaccharide-mediated increase in tumour necrosis factor-alpha (TNF-alpha) levels. These results provide, for the first time, evidence to support the anti-inflammatory activity of amburoside A and isokaempferide that seems to be related to an inhibition of inflammatory mediators, such as TNF-alpha, as well as histamine, serotonin and prostaglandin E(2), besides leucocyte infiltration in a dose- or concentration-dependent manner. These anti-inflammatory effects can be explained, at least in part, by the ability of these compounds to reduce neutrophil degranulation, myeloperoxidase activity, mediators as well as TNF-alpha secretion.

Topically applied diterpenoids from Egletes viscosa (Asteraceae) attenuate the dermal inflammation in mouse ear induced by tetradecanoylphorbol 13-acetate- and oxazolone.

The diterpene compounds, centipedic acid (CA) and 12-acetoxyhawtriwaic acid lactone (AHAL, tanabalin) isolated from the flower buds of Egletes viscosa LESS. (Asteraceae) were evaluated on acute and chronic models of mouse ear dermatitis. A single topical application of CA (0.125; 0.25 and 0.5 mg/ear) or AHAL (0.125, 0.25, 0.5 mg/ear) immediately before 12-O-tetradecanoylphorbol-13-acetate (TPA, 2.5 mug/ear) caused a dose-related significant inhibition of ear inflammatory edema and influx of polymorphonuclear cells, as evidenced by a decrease in ear thickness and reduced myeloperoxidase (MPO) activity and tumor necrosis factor-alpha (TNF-alpha) in ear tissue homogenates. The maximal obtained inhibition for both ear edema and neutrophil influx were almost similar to that of topically applied dexamethasone (0.05 mg/ear). The extent of inhibitions for the respective treatments of CA (0.5 mg/ear), AHAL (0.5 mg/ear), or dexamethasone (0.05 mg/ear) were in the order of 63%, 61% and 81% for the ear edema, and 90%, 95% and 95% for the neutrophil influx. Also, at similar doses, both diterpenes and dexamethasone effectively inhibited the delayed-type hypersensitivity reaction induced by repeated topical application of 1% oxazolone (OXA, 20 microl/ear), as evidenced by significant decreases in ear thickness and interferon-gamma (INF-gamma) levels in ear tissue. Histopathological analysis revealed a marked decrease in epidermal hyperplasia and neutrophil infiltration in animals pretreated with CA or AHAL, in a manner similar to dexamethasone. These data provide evidence for the anti-dermatitis effect of Egletes viscosa diterpenes, by mechanisms that involve a reduced neutrophil influx and decreased production of inflammatory cytokines, TNF-alpha and IFN-gamma.

Gastroprotective mechanisms of centipedic acid, a natural diterpene from Egletes viscosa LESS.

This study was aimed to clarify the mechanisms of gastroprotection by centipedic acid (CPA), a natural diterpene from Egletes viscosa LESS. (Asteraceae) using ethanol-induced gastric mucosal damage in mice and gastric secretion in 4-h pylorus-ligated rats as model systems. In mice, intragastrically administered CPA (25, 50, 100 mg/kg) greatly reduced the mucosal lesions induced by 96% ethanol (0.2 ml, p.o.) by 18, 53, and 79%, respectively, whereas N-acetylcysteine (NAC, 300 mg/kg, i.p.), the reference compound produced a 50% inhibition. In 4-h pylorus-ligated rats, CPA (50 mg/kg) applied intraduodenally decreased both gastric secretory volume and total acidity. Similar to NAC, the plant diterpene effectively prevented the ethanol associated decrease in non-proteic sulfhydryls (NP-SH) and the elevated thiobarbituric acid-reactive substances (TBARS) in gastric tissue, suggesting that these compounds exert an antioxidant effect. Pretreatment of mice with indomethacin, the cyclooxygenase inhibitor but not with capsazepine, the transient receptor potential vanilloid-1 (TRPV1)-receptor antagonist greatly suppressed the gastroprotective effect of CPA. Furthermore, CPA gastroprotection was significantly attenuated in mice pretreated with L-NAME or glibenclamide the respective inhibitors of nitric oxide synthase and K(+)(ATP) channel activation. These data suggest that CPA affords gastroprotection by different and complementary mechanisms, which include a sparing effect on NP-SH reserve, and roles for endogenous prostaglandins, nitric oxide, and TRPV1-receptor and K(+)(ATP) channel activation.

Evaluation of the genotoxicity of piplartine, an alkamide of Piper tuberculatum, in yeast and mammalian V79 cells.

The genus Piper belongs to the Piperaceae family, and includes species of commercial and medicinal importance. Chemical studies on Piper species resulted in the isolation of several biologically active molecules, including alkaloid amides, such as piplartine. This molecule, isolated from Piper tuberculatum, has significant cytotoxic activity against tumor cell lines, and presents antifungal, anti-platelet aggregation, anxiolytic, and antidepressant effects. In order to understand the biological properties of piplartine, this study investigated the genotoxicity and the induction of apoptosis by piplartine in V79 cells and its mutagenic and recombinogenic potential in Saccharomyces cerevisiae. Piplartine induced dose-dependent cytotoxicity in S. cerevisiae cultures in either stationary -- or exponential growth phase. In addition, piplartine was not mutagenic when cells were treated during exponential-growth phase and kept in buffer solution, but it increased the frequencies of point, frameshift, and forward mutations when cells were treated in medium during growth. Piplartine treatment induced DNA strand breaks in V79 cells, as detected by neutral and alkaline comet assay. In cell cycle analysis, piplartine induced G2/M cell cycle arrest, probably as a consequence of the DNA damage induced and repair. Moreover, piplartine treatment induced apoptosis in a dose-dependent manner, as observed by a decrease in mitochondrial membrane potential and an increase in internucleosomal DNA fragmentation. These data suggest that the DNA damage caused by piplartine induces G2/M cell cycle arrest, followed by apoptosis. Moreover, we suggest that cells surviving piplartine-induced DNA damage can accumulate mutations, since this alkaloid was mutagenic and recombinogenic in S. cerevisiae assays.

Piplartine induces inhibition of leukemia cell proliferation triggering both apoptosis and necrosis pathways.

Piplartine {5,6-dihydro-1-[1-oxo-3-(3,4,5-trimethoxyphenyl)-2-propenyl]-2(1H)pyridinone} is an alkaloid/amide component of Piper species. The purpose of the present study was to examine the antiproliferative effects of piplartine on human leukemia cell lines HL-60, K562, Jukart, and Molt-4 using the trypan blue exclusion method, as well as the effect of piplartine on DNA synthesis. The viability of all human leukemia cell lines were not affected by piplartine after 6 h, 9 h, and 12 h exposure, whereas a steady decline was seen after an exposure time of 24 h. The antiproliferative activity of piplartine seemed to be related to the inhibition of DNA synthesis, as revealed by the reduction of 5-bromo-2'-deoxyuridine (BrdU) incorporation after 24h of incubation. Piplartine-mediated reduction in cell number was associated with an increasing number of dead cells at a concentration of 10 microg/ml. These findings were corroborated by morphologic analysis. However, at the lowest concentration (2.5 microg/ml), piplartine-treated cells exhibited typical apoptotic morphological changes. The increase in caspase-3 activity was also observed in lysates of piplartine-treated cells (2.5 microg/ml). Our findings suggest that piplartine can suppress leukemia growth and reduce cell survival, triggering both apoptosis and/or necrosis, depending on the concentration used.