Cacalol derivatives from Roldana angulifolia

Modified Eremophilanes from Parasenecio hastatus and Their Neuroprotective Activities

The new modified eremophilanes hastatusins A-K (1-11) and 13 known compounds (12-24) were isolated from Parasenecio hastatus. The structures of 1-24 were elucidated based on spectroscopic data analysis and comparison with literature data. The absolute configurations of compounds 1 and 2 were defined by single-crystal X-ray diffraction analysis, and the other new compounds were assigned based on ECD data. This work is the first report of the crystal structure of an 8,9-seco-eremophilanolide (1) with two lactone units. The enantiomers of 1 were separated by chiral-phase HPLC, and the absolute configurations of (-)-1 and (+)-1 were established via experimental and calculated ECD data. The new compounds represent four unusual skeletons: a modified 8,9-seco-eremophilane featuring a rare 6,9;8,12-dilactone moiety (1), a furanoeremophilane-type skeleton (2-7, 11), a rare C₁₄ nor-eremophilane-type skeleton (8, 9), and a modified eremophilane lactone-type skeleton (10). All isolates were assayed for their neuroprotective effects against H₂O₂-induced SH-SY5Y cell injury, and compounds 2-5, 12, 21, and 23 exhibited activities even at a low concentration of 1 μM. Compounds 6-9, 13, 14, 17, 20, 22, and 24 also showed notable effects at 10 and 100 μM.

Maturin acetate from Psacalium peltatum (Kunth) Cass. (Asteraceae) induces immunostimulatory effects in vitro and in vivo

Maturin acetate (MA) is one of main constituents in Psacalium peltatum. The cytotoxic effects of MA on tumorigenic cells were evaluated using the MTT assay. The in vitro immunostimulatory effects of maturin acetate (MA) were evaluated on the viability of murine splenocytes and macrophages, and human peripheral blood mononuclear cells (PBMC). The effects of MA on the production of nitrous oxide, pinocytosis and lysosomal enzyme activity were assayed in murine macrophages RAW 264.7. The effects of MA on the NK cell activity were also assayed. The in vivo immunostimulatory activities of MA were evaluated on BALB/c mice immunosuppressed with cyclophosphamide (CY). MA lacks cytotoxic activity against human cancer cells (IC50>200 μM). In the absence of LPS, MA 10 μM or higher stimulated significantly (P≤0.05), compared to untreated cells (-LPS), the viability of murine macrophages and splenocytes. In the absence of LPS, MA 10 μM or higher stimulated significantly (P≤0.05), compared to untreated cells (-LPS), the lysosomal enzyme activity and pinocytosis. In immunosuppressed mice, MA increases significantly (P≤0.05), compared to CY-treated mice, the production of IL-2 and IL-15 and IFN-γ. In conclusion, MA exerts immunostimulatory activities in vitro and in vivo.

Mexican medicinal plants used for cancer treatment: pharmacological, phytochemical and ethnobotanical studies

AIM OF THE STUDY

This review provides a summary of Mexican medicinal flora in terms of ethnobotanical, pharmacology, and chemistry of natural products related to anticancer activity.

MATERIALS AND METHODS

Bibliographic investigation was carried out by analyzing recognized books and peer-reviewed papers, consulting worldwide accepted scientific databases from the last five decades. Mexican plants with attributed anti-cancer properties were classified into six groups: (a) plant extracts that have been evaluated for cytotoxic effects, (b) plant extracts that have documented anti-tumoral effects, (c) plants with active compounds tested on cancer cell lines, (d) plants with novel active compounds found only in Mexican species, (e) plants with active compounds that have been assayed on animal models and (f) plants with anti-cancer ethnopharmacological references but without scientific studies.

RESULTS

Three hundred plant species belonging to 90 botanical families used for cancer treatment have been recorded, of which only 181 have been experimentally analyzed. The remaining 119 plant species are in use in empirical treatment of diseases consistent with cancer symptomatology. Only 88 of the plant extracts experimentally studied in in vitro cellular models have demonstrated active cytotoxic effects in at least one cancer cell line, and 14 out of the 88 have also been tested in vivo with the results that one of them demonstrated anti-neoplasic effects. A total of 187 compounds, belonging to 19 types of plant secondary metabolites, have been isolated from 51 plant extracts with active cytotoxic effects, but only 77 of these compounds (41%) have demonstrated cytoxicity. Seventeen of these active principles have not been reported in other plant species. However, only 5 compounds have been evaluated in vivo, and 3 of them could be considered as active.

CONCLUSION

Clearly, this review indicates that it is time to increase the number of experimental studies and to begin to conduct clinical trials with those Mexican plants and its active compounds selected by in vitro and in vivo activities. Also, the mechanisms of action by which plant extracts and their active compounds exert anti-cancer effects remain to be studied.

Terpenoids from the aerial parts of Parasenecio deltophylla

Five new modified eremophilane-type sesquiterpenes (1-5), including three norsesquiterpenes (1-3), and one new monoterpene (6) were isolated from the aerial parts of Parasenecio deltophylla. Their structures were established on the basis of HRMS and NMR methods. The cytotoxicity of compounds 1-4 and 6 against selected cancer cell lines, including human promyelocytic leukemia (HL-60) and human hepatoma (Hep-G2), was evaluated. Antioxidant activities of these compounds were assessed by ABTS and DPPH methods.