Antispasmodic Effects of Hydroalcoholic Extract from Gochnatia polymorpha sp. floccosa in the Guinea Pig Ileum

Actions of sesquiterpene lactones isolated from Moquiniastrum polymorphum subsp. floccosum in MCF7 cell line and their potentiating action on doxorubicin

Background

In order to obtain better clinical results in anticancer therapies, polychemotherapy or combination therapies are used. For this, the combinations are required to increase the efficacy and reduce the adverse reactions of the associated chemotherapies. The aim of this study was to evaluate the cytotoxic, apoptotic and (anti)proliferative potential of two sesquiterpene lactones isolated from Moquiniastrum polymorphum, 11,13-diidrozaluzanin C (1) and gochnatiolide C (2), and their associations with chemotherapeutic agents irinotecan, tamoxifen, cisplatin, 5-fluouracyl and doxorubicin in the tumoral lineage of MCF-7 breast adenocarcinoma.

Methods

The analyses were performed by MTT cytotoxicity assays, drug combination index (CI), apoptosis morphological assay and cell proliferation assay. Treatments were evaluated with short exposure times (4 h), followed or not by recovery in drug-free medium for 24 h. For the cell viability assay the statistical analysis was performed using software INSTAT, and the ANOVA/Tukey test was applied. Combination Indices (CI) was made using CompuSyn software and demonstrated through isoboles. The assays that evaluated cell death and proliferation used statistical analysis SAS 9.4 (Statistical Analysis System), and the procedure adopted was PROC NPAR1WAY. The Wilcoxon test at 5% level was applied for comparing statistical differences.

Results

The results demonstrated that the compounds decrease cell viability and increase their action when associated with irinotecan, tamoxifen and doxorubicin (CI < 1 and CI = 1). In periods of 4 h-exposure, the compounds cause cell death by apoptosis and after 24 h, they increase the mean number of cells in programmed cell death, especially when treated with 2. In addition, the association with doxorubicin increases the apoptotic potential induced by tested compounds. Both isolates had effect on the reduction of the number of mitoses, especially when 2 at its highest concentration is associated with doxorubicin.

Conclusions

Finally, these compounds are presented as potential agents in chemotherapy combined with doxorubicin, since they trigger the mechanism of apoptosis, which, through the mechanism of action of sesquiterpene lactones, leads to a reduction in toxicity. In addition, the tested compounds have the ability to exert a synergistic action with doxorubicin, possibly by down-regulating the drug resistance mechanisms.

A New Sesquiterpene Lactone and Other Constituents of Moquiniastrum polymorphum subsp. floccosum (Asteraceae)

A new guaianolide, 1 S, 3 S, 5 R, 6 S, 7 S, 11 R-1-hydroxy-11α,13-dihydrozaluzanin C (1), was isolated from Moquiniastrum polymorphum subsp. floccosum trunk bark, together with fifteen known compounds, which were identified as 11α,13-dihydroglucozaluzanin C (2), 8α-hydroxy-11α,13-dihydrozaluzanin C (3), zaluzanin C (4), gochnatiolide B (5), ethyl caffeate (6), methyl chlorogenate (7), ethyl chlorogenate (8), methyl 3,5-dicaffeoyl quinate (9), ethyl 3,5-dicaffeoyl quinate (10), methyl 4,5-dicaffeoyl quinate (11), ethyl 4,5-dicaffeoyl quinate (12), ethyl 3,4-dicaffeoyl quinate (13), 3,5-dicaffeoyl quinic acid (14), 4,5-dicaffeoyl quinic acid (15), and 3,4-dicaffeoyl quinic acid (16). With the exception of 5, all known compounds are being reported for the first time in M. polymorphum.

Antiedematogenic effects of the polar fractions of Persea cordata Mez. (Lauraceae) on microvascular extravasation in rat skin

ETHNOPHARMACOLOGICAL RELEVANCE

Persea cordata Mez. (Lauraceae) is a medicinal plant used in veterinary ethnopharmacology, which is a popular medicine used as an anti-inflammatory and healing agent, mainly on animal skin diseases, characterized by cutaneous open wounds, in South Brazil.

AIM OF THIS STUDY

The purpose of this study was to investigate a possible antiedematogenic effect of ethyl acetate (EtAc) and butanol (BuOH) polar fractions of Persea cordata on Evans blue dye leakage induced by pro-inflammatory agents in rat skin.

MATERIALS AND METHODS

Male Wistar rats (180-200 g, n=5-6) were pretreated with a single intraperitoneal administration of EtAc or BuOH (1 to 600 mg kg(-1)) fractions followed by intravenous Evans blue dye injection (1%, 30 mg kg(-1), i.v.), 60 min before the injection of phlogistic agents. Animals received intradermal injections (0.05 ml) of carrageenan (CAR, 300 µg/site), 48/80 compound (C4880, 10 µg/site), histamine (HIS, 0.3 µg/site), serotonin (5-HT, 0.01 µg/site), dextran (DEX, 200 µg/site), bradykinin (BK, 0.003 µg/site), capsaicin (CPS, 400 µg/site), substance P (SP, 0.003 µg/site) or prostaglandin E2 (PGE2 10 nmol/site) and they were submitted to euthanasia after 60 min. Skin samples were obtained in the extravasation sites of Evans blue dye. Skin fragments were soaked in formamide at 37°C (during 24h) for Evans blue extraction. The amount of dye leakage in the tissue fragment was determined by a spectrophotometer (620 nm).

RESULTS

In a very similar manner in terms of potency and efficacy, systemic administration of EtAc and BuOH fractions caused dose-dependent inhibition of vascular Evans blue dye leakage induced by phlogistic agents in the rat skin. The results obtained (ID50 values in mgkg(-1) and maximal inhibition in %) with EtAc fraction, as follows were: CAR (34.42 and 63.0), 4880 (8.52 and 59.1), HIS (21.22 and 66.8), 5-HT (32.99 and 73.4), DEX (41.74 and 67.0), BK (34.03 and 68.0), CPS (100.7 and 77), SP (2.1 and 78.9) and PGE2 (133 and 71.0). BuOH fraction significantly inhibited CAR (25.9 and 70)-, 4880 (36.8 and 66)-, HIS (17.6 and 77)-, 5-HT (32.8 and 56)-, DEX (89.6 and 75)-, BK (28.0 and 66)-, CPS (136.37 and 71)-, SP (5.6 and 78)- and PGE2 (109.64 and 56)-induced VE, respectively.

CONCLUSION

Systemic administration of Persea cordata polar fractions exerts a non-specific inhibitory effect on microvascular leakage induced by pro-inflammatory agents in rat skin, probably to interfering with different biological systems involved in the development of the inflammatory process, reinforcing the popular use of Persea cordata as an anti-inflammatory and healing agent for skin.