Solid lipid nanoparticles improve octyl gallate antimetastatic activity and ameliorate its renal and hepatic toxic effects.

Metastasis is the main cause of cancer-related death and requires the development of effective treatments with reduced toxicity and effective anticancer activity. Gallic acid derivatives have shown significant biological properties including antitumoral activity as shown in a previous study with octyl gallate (G8) in vitro. Thus, the aim of this work was to evaluate the antimetastatic effect of free and solid lipid nanoparticle-loaded G8 in mice in a lung metastasis model. Animals inoculated with melanoma cells presented metastasis in lungs, which was significantly inhibited by treatment with G8 and solid lipid nanoparticle-loaded G8, named G8-NVM. However, G8-treated mice showed an increase in several toxicological parameters, which were almost completely circumvented by G8-NVM treatment. This study supports the need for pharmacological studies on new potential medicinal plants to treat cancer and can provide new perspectives on using nanotechnology to improve biological activities while decreasing the chemotherapy toxicological effects of anticancer drugs.

Assessment of In Vitro Biological Activities of Anthocyanins-Rich Plant Species Based on Plinia cauliflora Study Model.

Plinia cauliflora (jaboticaba) is a native fruit tree from Brazilian rainforest widely used in popular medicine to prevent diarrhea, asthma, and infections. Studies have shown that the major therapeutic potential of jaboticaba fruits is on its peel, a rich source of anthocyanins. These secondary metabolites have well-known antioxidant and anti-inflammatory activities and have been claimed to be effective to treat diabetes, cancer, cardiovascular diseases, and stroke. This chapter describes a series of methodologies to evaluate important in vitro biological activities like cytotoxicity, proliferation, and migration of a hydroalcoholic extract of jaboticaba peel on mouse fibroblast L929 line. Assays to assess total phenolic, flavonoid, and anthocyanin contents and antioxidant activities are described as well.

Seasonal influence and cytotoxicity of extracts, fractions and major compounds from Allamanda schottii

The aim of this research was to evaluate the fractions obtained from the leaf, stem and roots of Allamanda schottii Pohl, Apocynaceae, responsible for the cytotoxicity, using several cell lines. Cytotoxicity was correlated with the season the part of the plant, and the major compounds were assessed. The ethanol extracts of leaves, stems and roots obtained at different seasons were evaluated in the human erythromyeloblastoid leukemia cell line (K562). Subsequently the ethanol extracts and dichloromethane fractions collected in winter were evaluated in mouse fibroblast cell line (Mus musculus) (L929), cervix adenocarcinoma (HeLa), human pre-B leukemia (Nalm6), as well as K562 cell line. The compounds plumericin, plumieride and ursolic acid isolated from ethanol extracts of the stems were evaluated in the same cell lines, as well as on breast adenocarcinoma cell line (MCF-7), and Mus musculus skin melanoma cell line (B16F10). The chromatographic profiles of the dichloromethane fractions were obtained by high performance liquid chromatography. The results revealed that the season during which A. schottii was collected, and the part of the plant analyzed, influence the cytotoxicity on the K562 cells tested. On the other hand the dichloromethane fractions, mainly from the stems and roots, are responsible for the cytoxicity on the cells tested. These results may be associated with the seasonal variation of plumericin in these parts of the plant. This information is in accordance with the HPLC analysis. The results clearly show the potential for the phytotherapeutic use of this species, and suggest that the cytotoxic activity observed may be due to the presence of plumericin, or to minor compounds not yet identified. The seasonal influence on the production of secondary metabolites was verified.

Development and validation of an HPLC-PDA method for the determination of myrsinoic acid B in the extracts of Rapanea ferruginea Mez.

New, simple, rapid and precise HPLC-PDA method has been developed and validated for quantification of biomarker myrsinoic acid B in stem bark extracts of Rapanea ferruginea Mez. The method employs a Phenomenex C18 column (250 mm × 4.6mm I.D., 5 µm) with acetonitrile:methanol:water (pH 2.6 with phosphoric acid) at 48:30:22 as mobile phase, at a flow rate of 0.7 mL min(-1) and photo diode array (PDA) detection at 270 nm. The validation data show that the method is specific, accurate, precise and robust. The method was linear, over a range of 5-100.0 µg mL(-1), with a limit of detection of 0.369 µg mL(-1) and limit of quantification of 1.233 µg mL(-1). The method has also shown consistent recoveries (average of 101.3% and 0.12% RSD) of the biomarker, with low intra and inter-day relative standard deviation (1.26% and 1.62%, respectively). The evaluated hydroethanolic extract and dry extract presented MAB values of 63.53 and 36.07 mg g(-1), respectively.

Evaluation of antiviral activity of South American plant extracts against herpes simplex virus type 1 and rabies virus.

This paper describes the screening of different South American plant extracts and fractions. Aqueous and organic extracts were prepared and tested for antiherpetic (HSV-1, KOS and 29R strains) and antirabies (PV strain) activities. The evaluation of the potential antiviral activity of these extracts was performed by using an MTT assay for HSV-1, and by a viral cytopathic effect (CPE) inhibitory method for rabies virus (RV). The results were expressed as 50% cytotoxicity (CC(50)) for MTT assay and 50% effective (EC(50)) concentrations for CPE, and with them it was possible to calculate the selectivity indices (SI = CC(50)/EC(50)) of each tested material. From the 18 extracts/fractions tested, six extracts and four fractions showed antiviral action. Ilex paraguariensis, Lafoensia pacari, Passiflora edulis, Rubus imperialis and Slonea guianensis showed values of SI > 7 against HSV-1 KOS and 29-R strains and Alamanda schottii showed a SI of 5.6 against RV, PV strain.

Naturally occurring compounds affect glutamatergic neurotransmission in rat brain.

Natural products, including those derived from plants, have largely contributed to the development of therapeutic drugs. Glutamate is the main excitatory neurotransmitter in the central nervous system and it is also considered a nociceptive neurotransmitter, by acting on peripheral nervous system. For this reason, in this study we investigated the effects of the hydroalcoholic extracts from Drymis winteri (polygodial and drimanial), Phyllanthus (rutin and quercetine), Jathopha elliptica (jatrophone), Hedyosmum brasiliense (13HDS), Ocotea suaveolens (Tormentic acid), Protium kleinii (alphabeta-amyrin), Citrus paradise (naringin), soybean (genistein) and Crataeva nurvala (lupeol), described as having antinociceptive effects, on glutamatergic transmission parameters, such as [(3)H]glutamate binding, [(3)H]glutamate uptake by synaptic vesicles and astrocyte cultures, and synaptosomal [(3)H]glutamate release. All the glutamatergic parameters were affected by one or more of these compounds. Specifically, drimanial and polygodial presented more broad and profound effects, requiring more investigation on their mechanisms. The putative central side effects of these compounds, via the glutamatergic system, are discussed.

Antibacterial activity of extract, fractions and four compounds extracted from Piper solmsianum C. DC. VAR. solmsianum (Piperaceae).

Piper solmsianum C. DC. var. solmsianum (Piperaceae) is a shrub commonly found in areas with wet tropical soils. Other Piper species have been used in folk medicine as antitumoral and antiseptic agents. We studied the crude methanolic extract, some organic fractions and compounds isolated from this plant for possible antimicrobial activity against Gram-positive and Gram-negative bacteria. The bioautographic assays disclosed three inhibition zones. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were determined showing excellent activity, particularly against the Gram-positive bacteria (Bacillus cereus, Staphylococcus aureus, Staphylococcus saprophyticus and Streptococcus agalactiae). It appears that the antimicrobial activity of Piper solmsianum is related mainly to the presence of conocarpan and eupomatenoid-5 (neolignans). However another, as yet unidentified, active compound could also be extracted from the plant.

Evaluation of the anti-proliferative effect the extracts of Allamanda blanchetti and A. schottii on the growth of leukemic and endothelial cells.

PURPOSE: To investigate the anti-proliferative effect of A. blanchetti and A. schottii extracts. METHODS: The anti-proliferative effect of A. blanchetti and A. schottii ethanolic extracts on K562 leukemic cells as well as on BMEC and HUVEC were evaluated. Phytochemical analysis to identify the possible active components was carried out. RESULTS: The root extract of A. schottii was the most active of them. At 80 microg/mL, the root extracts showed a cytostatic effect on K562, whereas at 400 microg/mL, there was a strong cytotoxic effect. Similar cytostatic and cytotoxic effects were seen in the endothelial cells, but at lower doses. The effect of A. schottii root extract on endothelial cells was seen at concentrations ten times lower (8 microg/mL) than the effect of the A. blanchetti root extract (80 microg/mL). Phytochemical investigation of different fractions and parts of the plant led to the isolation of several known compounds, some of which are described for the first time in the genus Allamanda, and with previous evidence of anticancer and antitumoral properties. CONCLUSIONS: Our results suggest that both plants studied exhibit cytostatic and cytotoxic activity, but the most active compounds are located in the roots.

Anti-edematogenic effects of velutinol A isolated from Mandevilla velutina: evidence for a selective inhibition of kinin B1 receptor-mediated responses.

This study assesses the effects of compound velutinol A obtained from M. velutina in the rat paw edema induced by several phlogistic agents. Attempts were made to analyze how velutinol A is able to inhibit kinin B(1) receptor-mediated inflammatory responses. Velutinol A (100 nmol/paw) partially reduced (about 30%) the edema evoked by carrageenan (300 microg/paw). However, velutinol A (100 nmol/paw) failed to affect the edema induced by histamine (200 nmol/paw), substance P (30 nmol/paw), PAF (10 nmol/paw) or BK (3 nmol/paw). Interestingly, the edema caused by the selective kinin B(1) receptor agonist des-Arg(9)-BK (100 nmol/paw) in animals pre-treated with PAF or LPS was significantly inhibited by velutinol A (100 nmol/paw) (48 and 46%, respectively). A similar inhibition of des-Arg(9)-BK-induced edema after pre-treatment with PAF was obtained with the non-peptidic and selective B(1) receptor antagonist SSR 240612 (60 nmol/paw) (46%). In addition, the systemic administration of velutinol A (10 mg/kg, i.p.) or SSR 240612 (1 mg/kg, i.p.) also caused a significant reduction of des-Arg(9)-BK (100 nmol/paw)-induced edema in PAF-treated rats (51 and 43%, respectively). The results provide convincing evidence that velutinol A selectively blocks the edema responses mediated by B(1) receptor activation in vivo. This compound might represent a new non-peptidic and selective antagonist for kinin B(1) receptors.

The sesquiterpenes polygodial and drimanial in vitro affect glutamatergic transport in rat brain.

Natural products including those derived from plants, have over the years greatly contributed to the development of therapeutic drugs. Polygodial and drimanial are sesquiterpenes isolated from the bark of the plant Drymis Winteri (Winteraceae) that exhibit antinociceptive properties. Since peripheral glutamate presents nociceptive actions, in this study it was investigated the effects of hydroalcooholic extracts from Drymis winteri (polygodial and drimanial) on the glutamatergic system in rat brain. Polygodial and drimanial inhibited glutamate uptake by astrocytes, as well as by cortical, hippocampal and striatal slices, and increased synaptosomal glutamate release. These concurrent effects would predispose to an increase in the extracellular glutamate concentrations, leading to possible neurotoxic effects (excitotoxicity) of these natural compounds, which would suggest the need for some caution in their therapeutic application.

Antinociceptive properties produced by the pregnane compound velutinol A isolated from Mandevilla velutina.

Velutinol A is a pregnane compound isolated from the rhizomes of the Brazilian plant Mandevilla velutina that interferes with kinin actions and possesses anti-inflammatory action. Here, we investigate the effect produced by velutinol A in different models of inflammatory nociception. The nociceptive effect caused by the intraplantar injection of phorbol myristate acetate (PMA, 50 pmol/paw) in mice was practically abolished by coadministration of velutinol A (1-10 nmol/paw). In contrast, the coadministration of velutinol A (10 nmol/paw) failed to affect the nociceptive response elicited by either bradykinin (BK, 10 nmol/paw) or prostaglandin E(2) (PGE(2), 10 nmol/paw). Of note, velutinol A (10 nmol/paw) partially inhibited the nociceptive response caused by capsaicin (1 nmol/paw). However, velutinol A (10 microM) did not significantly interfere with the specific binding sites of [(3)H]resiniferatoxin or [(3)H]BK in vitro. Our data also suggest that these effects are related with its ability to interact with kinin B(1) receptor-mediated mechanisms, as the cotreatment of mice with velutinol A (10 nmol/paw) consistently blocked the nociceptive response induced by the selective B(1) receptor agonist des-Arg(9)-BK. Finally, the persistent hyperalgesia produced by intraplantar injection of carrageenan (300 microg/paw) was completely reversed by the coadministration of velutinol A (10 nmol/paw). Collectively, the present results show that the pregnane compound velutinol A produces peripheral antinociceptive action in some models of acute and persistent inflammatory pain by interacting with kinin B(1)-receptor mediated effects. Thus, velutinol A or its derivatives could constitute an attractive molecule of interest for the development of new analgesic drugs. Additional studies are now in progress in order to further explore its precise mechanism of action on B(1) receptor pathways.

A new triterpene with antinociceptive activity from Maytenus robusta.

A new triterpene 3,15-dioxo-21alpha-hydroxy friedelane has been isolated from methanol extract of Maytenus robusta and its structure elucidated on the basis of spectral analysis. Stigmasterol, friedelin, friedelanol and 3,15-dioxo friedelane were also obtained. 3,15-dioxo-21alpha-hydroxy friedelane was analyzed against the writhing test in mice and exhibited potent dose-dependent effects with an ID50 value of 12.5 +/- 2.1 micromol kg(-1) and a maximal inhibition of 85.90%. It was about 10-fold more active than aspirin and paracetamol, used as reference drugs.

Antifungal activity of drimane sesquiterpenes from Drimys brasiliensis using bioassay-guided fractionation.

PURPOSE: This study describes the antifungal effect of extracts and compounds isolated from Drimys brasiliensis acting against dermatophytes. METHODS: The activities were evaluated by using the microbroth dilution method. RESULTS: Bioassay-guided fractionation of the most active extract from the bark (CHCl3) led to the isolation of the sesquiterpene drimanes polygodial, 1-beta-(p-methoxycinnamoyl)-polygodial, drimanial and 1-beta-(p-cumaroyloxy)-polygodial, which were selectively active against Epidermophyton floccosum and Tricophyton rubrum. CONCLUSIONS: The selective antifungal activity reported in this paper for drimanes isolated from D. brasiliensis opens the possibility that they could be helpful for the developing of new antifungal agents for treating the difficult to eradicate dermatomycoses produced by E. floccosum.

Evaluation of anti-herpetic and antioxidant activities, and cytotoxic and genotoxic effects of synthetic alkyl-esters of gallic acid.

The n-alkyl esters of gallic acid (CAS 13857-8) have a diverse range of uses as antioxidants in food, cosmetics and pharmaceutical industries. Pharmaceutical studies performed with these compounds have found that they have many therapeutic potentialities including anti-cancer, antiviral and antimicrobial properties. However, more interest has been devoted to their antioxidant activity due to the ability to scavenge and reduce reactive oxygen species (ROS) formation. In this study, gallic acid and 14 different alkyl gallates were tested. The cytotoxicity and anti-herpetic (HSV-1, KOS and 29-R strains) activity were studied by using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) colorimetric assay and the cell viability by using the Trypan blue dye exclusion method. The genotoxicity was studied by the Comet assay and the antioxidant activity by using the DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging and microsomal lipid peroxidation-inhibiting activities. The results showed that all the tested compounds have anti-herpetic activity at non cytotoxic concentrations with selectivity indices (SI = CC50/EC50) varying from 0.89 to 18.34, depending on the used HSV-1 strain. It was observed that all tested alkyl gallates showed some degree of genotoxicity, at the tested concentrations, except cetyl gallate, at 256.60 micromol/L (p <0.05, t-Student test), probably induced by ROS released by infected cells and/or by the alkyl gallates that were not antioxidants, at the tested concentrations, in which they demonstrated anti-herpetic activity. The hydroxyl groups can induce DNA damage due interactions with some metal ions, which are naturally present in the culture medium supplemented with fetal bovine serum, probably explaining the genotoxicity detected. However, the obtained results showed considerable antioxidant activity at smaller concentrations, when compared to quercetin which is considered as a reference drug due to its already described antioxidant potential: DPPH radical scavenging activity with IC50 values varying from 17 to 31 micromol/L; and microsomal lipid peroxidation-inhibiting activity with IC50 values varying from 21 to 59 micromol/L. It was observed that the presence of hydroxyl groups in these molecules is important for their pharmacological profile, but the length of the lateral carbonic chain does not have considerable influence.

Topical antiinflammatory effects of the ether extract from Protium kleinii and alpha-amyrin pentacyclic triterpene.

Protium kleinii (Burseraceae), a native Brazilian medicinal plant is claimed to be useful to treat some inflammatory states. Now we reported that topical application of either the ether extract or the main active constituent from P. kleinii the pentacyclic triterpene alpha-amyrin, all caused a dose-related inhibition of both ear oedema (ID50 values are 0.55 and 0.31 mg/ear, respectively) and influx of polymorphonuclear cells (ID50 values are 0.72 and 0.45 mg/ear, respectively) in response to topical application of 12-O-tetradecanoylphorbol-acetate (TPA) in the of mice ear. In terms of the efficacy, the maximal obtained inhibition for both ear oedema and neutrophil influx was very similar to that produced by the topical application of the steroidal antiinflammatory drug dexamethasone (DE; with inhibition of 70+/-5%, 66+/-3%, and 87+/-4% for oedema and 83+/-6%, 73+/-5%, and 91+/-3% for neutrophil influx, for the ether extract, alpha-amyrin, and dexamethasone, respectively). Likewise, both the ether extract and alpha-amyrin given topically dose-dependently prevented the increase of the proinflammatory cytokine interleukin-1beta levels in response to topical application of TPA. The calculated mean ID50 values are 1.81 and 0.53 mg/ear, respectively. Again, the efficacy of the extract and alpha-amyrin was very similar to that produced by dexamethasone (63+/-6%, 61+/-5%, and 74+/-5%, respectively). In marked contrast to phenidone, a lipo and cyclooxygenase inhibitor, neither the ether extract nor the alpha-amyrin inhibited arachidonic acid-mediated ear oedema in mice. Collectively, these results indicate that the active constituents present in the ether extract of P. kleinii including the pentacyclic triterpene alpha-amyrin are good candidates to develop a skin permeable antiinflammatory drug.

Paludolactone: a new eudesmanolide lactone from Wedelia paludosa DC. (Acmela brasiliensis).

Phytochemical investigation of the whole plant of Wedelia paludosa (Acmela brasiliensis) furnished a new eudesmanolide lactone, named paludolactone (2), in addition to the known eudesmanolide (1), stigmasterol, kaurenoic and oleanolic acids. 1H- and 13C-NMR, and MS spectroscopic and elemental analyses were used for the structural elucidation of these compounds.

Role of nitric oxide and K+ channels in relaxation induced by polygodial in rabbit corpus cavernosum in vitro.

This study examines the relaxation produced by the sesquiterpene polygodial and compares its action with those caused by acetylcholine (ACh) and sodium nitroprusside (SNP) in the rabbit corpus cavernosum (RbCC) in vitro. RbCC was set up in a 5-ml bath containing Krebs solution at 37 degrees C, at pH 7.2, and under 2 g of tension. Polygodial, ACh, and SNP elicited graded relaxation in RbCC with mean EC50 values of 46.70 microM, 0.38 microM, and 0.30 microM, respectively. The nitric oxide (NO) synthase inhibitor L-NOARG and the guanylate cyclase inhibitors LY 83583 and ODQ markedly inhibited the relaxation induced by polygodial (% of inhibition of 79, 48, and 51, respectively) and those caused by ACh (% of inhibition of 100, 49, and 32, respectively). Tetraethylammonium (TEA) and glibenclamide inhibited the relaxation induced by polygodial (52% and 43%, respectively), but only TEA caused shift to the right on ACh-mediated relaxation. In contrast, apamin, charybdotoxin, and 4-aminopyridine or the protein kinase A inhibitor KT 5720 all failed to affect either polygodial or ACh-mediated relaxation in these preparations. The authors concluded that polygodial produced graded relaxation in the RbCC in vitro via a mechanism that was partially dependent on the release of NO or a NO-derived substance through an activation of guanylate cyclase but was independent of adenylate cyclase mechanism. In addition, the opening of K+ channels sensitive to TEA and glibenclamide, but not those sensitive to apamin, 4-aminopyridine, or charybdotoxin, also contributed to the relaxant action produced by polygodial in the RbCC.

Anti-allodynic action of the tormentic acid, a triterpene isolated from plant, against neuropathic and inflammatory persistent pain in mice.

Experiments were designed to address whether the pentacyclic triterpene tormentic acid isolated from the stem bark of the plant Vochysia divergens exerts oral anti-allodynic properties in two models of chronic pain in mice: neuropathic pain caused by partial ligation of the sciatic nerve and inflammatory pain produced by intraplantar injection of Complete Freund's Adjuvant. Oral administration of tormentic acid (30 mg/kg) twice a day for several consecutive days produced time-dependent and pronounced anti-allodynia effect in both ispsilateral and contralateral paws after plantar injection of Complete Freund's Adjuvant. The inhibition observed was 82+/-9% and 100+/-11%, respectively. Interestingly, tormentic acid did not inhibit paw oedema formation following Complete Freund's Adjuvant plantar injection. Tormentic acid (30 mg/kg, p.o.) and gabapentin (70 mg/kg, p.o.), given twice a day, inhibited markedly the neuropathic allodynia induced by partial ligation of the sciatic nerve, with inhibition of 91+/-19% and 71+/-16%, respectively. The anti-allodynic action of tormentic acid was not associated with impairment of the motor activity of the animals. Together, the present results indicate that tormentic acid or its derivatives might be of potential interest in the development of new clinically relevant drugs for the management of persistent neuropathic and inflammatory allodynia.

Protective properties of butanolic extract of the Calendula officinalis L. (marigold) against lipid peroxidation of rat liver microsomes and action as free radical scavenger.

Calendula officinalis (marigold) has many pharmacological properties. It is used for the treatment of skin disorders, pain and also as a bactericide, antiseptic and anti-inflammatory. Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are known to participate in the pathogenesis of various human diseases and may be involved in the conditions which C. officinalis is used to treat. The aim of this study was to investigate the relationship between the beneficial properties of this plant and its antioxidant action. The butanolic fraction (BF) was studied because it is non-cytotoxic and is rich in a variety of bioactive metabolites including flavonoids and terpenoids. Superoxide radicals (O(2)(*-)) and hydroxyl radicals (HO(*)) are observed in decreasing concentrations in the presence of increasing concentrations of BF with IC(50) values of 1.0 +/- 0.09 mg/ml and 0.5 +/- 0.02 mg/ml, respectively, suggesting a possible free radical scavenging effect. Lipid peroxidation in liver microsomes induced by Fe(2+)/ascorbate was 100% inhibited by 0.5 mg/ml of BF (IC(50) = 0.15 mg/ml). Its total reactive antioxidant potential (TRAP) (in microM Trolox equivalents) was 368.14 +/- 23.03 and its total antioxidant reactivity (TAR) was calculated to be 249.19 +/- 14.5 microM. The results obtained suggest that the butanolic fraction of C. officinalis possesses a significant free radical scavenging and antioxidant activity and that the proposed therapeutic efficacy of this plant could be due, in part, to these properties.

Antinociceptive activity of the natural piperidine alkaloid hydrochlorides from Syphocampylus verticellatus.

In addition to 3'-methoxyluteolin and mixtures of sterols and triterpenes, the leaves of Syphocampylus Verticellatus yielded two piperidine alkaloid hydrochlorides, one of them has a novel structure. The alkaloids exhibit antinociceptive activity.