Ana Maria Quilez

Anti-secretory, anti-inflammatory and anti-Helicobacter pylori activities of several fractions isolated from Piper carpunya Ruiz & Pav.

ETHNOPHARMACOLOGICAL RELEVANCE The leaves of Piper carpunya Ruiz & Pav. (syn Piper lenticellosum C.D.C.) (Piperaceae), are widely used in folk medicine in tropical and subtropical countries of South America as an anti-inflammatory, anti-ulcer, anti-diarrheal and anti-parasitical remedy as well as an ailment for skin irritations. AIMS OF THE STUDY To study the anti-inflammatory, anti-secretory and anti-Helicobacter pylori activities of different fractions isolated from an ethanolic extract of the leaves of Piper carpunya, in order to provide evidence for the use of this plant as an anti-ulcer remedy. Moreover, to isolate the main compounds of the extract and relate their biological activity to the experimental results obtained with the fractions. MATERIALS AND METHODS Sixteen fractions were obtained from the ethanolic extract (F I-XVI) and 16 pure compounds were isolated and identified from these fractions. We studied the effects of the fractions (0.1-400microg/mL) on the release of myeloperoxidase (MPO) enzyme from rat peritoneal leukocytes, on rabbit gastric microsomal H(+), K(+)-ATPase activity and anti-Helicobacter pylori anti-microbial activity using the microdilution method (MM). The main compounds contained in the fractions were isolated and identified by (1)H- and (13)C NMR spectra analysis and comparison with the literature data. RESULTS Eight fractions showed inhibition of MPO enzyme (F I-IV, X, XII, XIV and XV). The highest inhibition was observed with F XIV (50microg/mL, 60.9%, p<0.001). F X and XII were the most active ones, inhibiting the gastric H(+), K(+)-ATPase activity with IC(50) values equal to 22.3microg/mL and 28.1microg/mL, respectively. All fractions, except F XV, presented detectable anti-Helicobacter pylori activity, with a diameter of inhibition zones ranging from 11mm up to 50mm. The best anti-Helicobacter pylori activity was obtained with F III and V. Both fractions killed Helicobacter pylori with lowest concentration values, about 6.25mug/mL. Sixteen pure compounds were isolated, five of them are flavonoids that possess strong anti-oxidant and free radical scavenging activity, e.g. vitexin, isovitexin, and rhamnopyranosylvitexin. Terpenoids like sitosterol, stigmasterol and phytol, which have shown gastroprotective activity, and dihydrochalcones, like asebogenin, with anti-bacterial activity, were also isolated. Furthermore, the rare neolignan 1, that is a DNA polymerase beta lyase inhibitor, and (6S, 9S)-roseoside, that shows strong anti-bacterial activity, were isolated, for the first time, from the genus Piper. CONCLUSIONS We suggest that the flavonoids isolated from F I and II (vitexin, isovitexin, rhamnopyranosylvitexin and isoembigenin) contribute to the anti-MPO activity, as well as to their anti-Helicobacter pylori activity. These flavonoids may also be responsible for the important inhibition of H(+), K(+)-ATPase activity. Also the phytosterols and phytol obtained from F XIV and XV could be involved in these gastroprotective activities. These results encourage us to continue phytochemical studies on these fractions in order to obtain full scientific validation for this species.

Anti-inflammatory activity of Agave intermixta Trel. and Cissus sicyoides L., species used in the Caribbean traditional medicine.

Agave intermixta Trel. and Cissus sicyoides L. are two tropical plants originating from the Dominican Republic. Aqueous extracts from these species are used in traditional medicine. In contrast, biological activity and toxicity of these plants are not yet evaluated systematically. The aim of the present work is to investigate a potential anti-inflammatory activity, and to elucidate the toxicity of the extracts. No lethal effects were produced after oral administration of the extracts. The values of the medium lethal doses after intraperitoneal administration were quite high for both species, although A. intermixta seems to be rather more toxic than C. sicyoides. The anti-inflammatory effects have been investigated in two experimental in vivo models. The carrageenan-induced rat paw oedema was chosen as a model for general inflammation, and the mice ear oedema test using tetradecanoylphorbol acetate as inflammatory agent as a model of topical inflammation. Dry extracts from decoctions of A. intermixta leaves and C. sicyoides stems were administered in doses of 300 and 500 mg/kg (p.o.) in the general model, and in doses of 3 and 5 mg/mouse ear for both plants in the topical model. In the general anti-inflammation assay, the oral administration of both extracts produced a significant anti-inflammatory effect, most pronounced for A. intermixta than for C. sicyoides. In the topical model, the administration of both extracts produced similar inhibitions of the oedema, with a reduction of approximately 50% in comparison with the control group. In homogenated tissue samples from the inflamed areas, a distinct decrease in the level of myeloperoxidase enzyme was noted.

Cytotoxic activity of Agave intermixta L. (Agavaceae) and Cissus sicyoides L. (Vitaceae)

The cytostatic activities of Agave intermixta L. (Agavaceae) and Cissus sicyoides L. (Vitaceae) have been determined. In the antimitotic assay, Agave intermixta L. showed complete inhibition of cell division at 24 h of treatment. Both species showed a moderate cytostatic activity against HEp‐2 cells, Cissus sicyoides L. being the most active species. Copyright

Phytochemical analysis and anti-allergic study of Agave intermixta Trel. and Cissus sicyoides L.

Agave intermixta Trel. (Maguey) and Cissus sicyoides L. (Bejuco caro) are Caribbean plant species from the Dominican Republic used locally in traditional popular medicine that have shown an anti‐inflammatory effect in experimental animal models. A phytochemical analysis on these species allowed us the isolation and identification of the steroidal sapogenins hecogenin and diosgenin from Maguey and the hydroxystilbene resveratrol from Bejuco caro. The effects of these plant extracts and their isolated constituents on compound‐48/80‐induced histamine release from peritoneal mast cells were investigated. Significant inhibition was produced by 0.5 mg mL−1 of a methanolic extract of Bejuco (41.1%) and by its constituent resveratrol (82.4%) at a dose of 250 μM. However, none of the steroidal sapogenins from A. intermixta showed a significant inhibitory effect on histamine release from mast cells. From these results, it can be deduced that the in‐vitro anti‐allergic activity towards the release of histamine from mast cells shown by the methanolic extract of C. sicyoides may be mediated by its constituent resveratrol and might contribute to the anti‐inflammatory activity shown by this species.

Uncaria tomentosa (Willd. ex. Roem. & Schult.) DC. and Eucalyptus globulus Labill. Interactions when Administered with Diazepam

The safety of natural drugs is defined by their side effects and toxicity as well as any interactions that may occur if taken together with other drugs. In particular, it is essential to identify synergies, antagonisms and other types of interference with other drugs so that the correct choice can be made from the range of phytomedicines available. The aim of this work was to investigate changes in the pharmacological effect of diazepam (2 mg/kg) on the CNS when administered together with a medicinal plant: Eucalyptus globulus Labill. (eucalyptus 6 mg/kg and 3.25 mg/kg) or Uncaria tomentosa (Willd. ex Roem. & Schult). DC. (cats claw, 7.14 mg/kg and 3.54 mg/kg). Various different psychopharmacological effects were evaluated through assessing exploratory behavior, muscle relaxation and spontaneous motor activity. Both phytodrugs interacted with the benzodiazepine. Eucalyptus had an inhibitory effect at both doses and could be useful at the highest dose in cases where the desired effect of the depressant is moderate anxiolytic activity without marked muscle relaxation. Cats claw, at both doses, enhanced the action of diazepam on spontaneous motor activity and, at the lowest dose, exploratory ability. These herbal drugs could be useful for their antiinflammatory activity in musculoskeletal pathologies treated with benzodiazepines. Copyright

Mitraphylline inhibits lipopolysaccharide-mediated activation of primary human neutrophils

BACKGROUND Mitraphylline (MTP) is the major pentacyclic oxindolic alkaloid presented in Uncaria tomentosa. It has traditionally been used to treat disorders including arthritis, heart disease, cancer, and other inflammatory diseases. However, the specific role of MTP is still not clear, with more comprehensivestudies, our understanding of this ancient herbal medicine will continue growing. HYPOTHESIS/PURPOSE Some studies provided its ability to inhibit proinflamatory cytokines, such as TNF-α, through NF-κB-dependent mechanism. TNF-α primes neutrophils and modulates phagocytic and oxidative burst activities in inflammatory processes. Since, neutrophils represent the most abundant pool of leukocytes in human blood and play a crucial role in inflammation, we aimed to determine the ability of MTP to modulate neutrophil activation and differentially regulate inflammatory-related cytokines. METHODS To determine the mechanism of action of MTP, we investigated the effects on LPS-activated human primary neutrophils responses including activation surface markers by FACS and the expression of inflammatory cytokines, measured by real time PCR and ELISA. RESULTS Treatment with MTP reduced the LPS-dependent activation effects. Activated neutrophils (CD16(+)CD62L(-)) diminished after MTP administration. Moreover, proinflamatory cytokines (TNF-α, IL-6 or IL-8) expression and secretion were concomitantly reduced, similar to basal control conditions. CONCLUSION Taken together, our results demonstrate that MTP is able to elicit an anti-inflammatory response that modulates neutrophil activation contributing to the attenuation of inflammatory episodes. Further studies are need to characterize the mechanism by which MTP can affect this pathway that could provide a means to develop MTP as new candidate for inflammatory disease therapies.

Gastroprotective Effects of Piper carpunya Against Diclofenac-Induced Gastric Lesions in Rats

Piper carpunya Ruiz & Pav. (Piper lenticellosum C. DC.), a member of the Piperaceae family, is a remedy with anti-inflammatory and antiulcer properties that is used in folk medicine in Ecuador. The present work determined the gastroprotective effects of this plant in a model of diclofenac-induced ulcers in rats and studied the mechanism involved. The aqueous suspension of the ethanol extract of the leaves of P. carpunya was administered twice orally to three groups of Wistar rats at doses of 62.5, 125, and 250 mg/kg, with a 24-h interval between doses. Diclofenac (100 mg/kg) was given 1 h after the last administration of the extract. Pretreatment with P. carpunya decreased the ulcerated area, prevented neutrophil infiltration induced by NSAID administration in vivo, and inhibited the release of the proteolytic enzyme myeloperoxidase by neutrophils stimulated with the calcium ionophore A23187. Superoxide dismutase activity demonstrated a marked increase at the two lowest doses of the extract versus diclofenac group and glutathione peroxidase activity was reverted near to sham levels. On the other hand, P. carpunya treatment did not prevent the increased levels of lipoperoxides in gastric mucosa caused by diclofenac. Furthermore, P. carpunya did not affect PGE2 levels, which were depleted by diclofenac treatment. These results suggest that the gastroprotective effect of P. carpunya in this experimental model appears through anti-inflammatory and antiradical mechanisms.

Potential therapeutic applications of the genus Annona: Local and traditional uses and pharmacology

ETHNO-PHARMACOLOGICAL RELEVANCE Annona species (Annonaceae) have long been used as traditional herbal medicines by native peoples in tropical areas. In different countries they are used against a large variety of illnesses, such as parasitic and infectious diseases, cancer, diabetes, peptic ulcers, and mental disorders. AIM OF THE STUDY This review aims to achieve a comprehensive understanding of the research conducted so far on the local and traditional uses, pharmacological activities, mechanism of actions of active compounds, toxicity, and possible interactions with other drugs of the Annona species. Through analysis of these findings, evidences supporting their applications in ethno-medicines are described. We discuss the possible research opportunities and stand out the weak points in our knowledge that deserves further investigation. MATERIAL AND METHODS Information on ethno-medicinal uses and pharmacological activities of the Annona genus was collected. The main scientific biomedical literature databases (Cochrane, PubMed, Scopus, Lilacs, SeCiMed, Elsevier, SpringerLink, Google Scholar, SciFinder) were consulted. The search covered all the literature available until September 2017. National and regional databases of Herbal Medicine and Complementary and Alternative Medicine were also revised in order to explore further data. For a better understanding of the therapeutic importance of these species, we have classified the pharmacological activities within each group of disorders. The International Classification of Diseases (ICD), used from WHO Member States, was chosen as the reference classification. RESULTS From among the 27 species revised, four species are highlighted for their important pharmacological activities in most of the groups of illnesses: A. muricata, A. squamosa, A. senegalensis, and A. cherimola. Many investigations have been performed with extracts from the leaves, bark, fruit and seeds and have shown a wide range of pharmacological activities, such as antiprotozoal, antitumoural, antidiabetic, hepato-protective, anti-inflammatory and anxiolytic activities. The chemistry on the annonaceous acetogenins (ACGs) has been extensively investigated due to their potent antitumoural activity. Many of the assays were carried out with the isolated acetogenins in different lines of tumour culture cells and were found effective at very low doses even in multidrug-resistant tumours, and hence constitute promising compounds in the treatment of different types of cancers. No studies were found with extracts rich in acetogenins in the clinical field. CONCLUSIONS The experimental results from the pharmacological research enable the validation of their traditional uses in several of the groups of diseases in the countries of origin and reveal these plants to be a valuable source for therapeutic molecules. However, more toxicity assays and clinical trials would be necessary to establish optimal and safe doses of consumption on the application of these medicinal plants.