The hexane, acetone and methanol extracts of Calophyllum brasiliense leaves were fractionated following a three bioassay guide: high HIV-1 RT inhibition, low cytotoxicity on MT2 cells and high inhibition of HIV-1 IIIb/LAV replication. This led to the isolation of three anti HIV-1 dipyranocoumarins: calanolides A and B and soulattrolide. In contrast, other isolated compounds such as apetalic acid, isoapetalic acid, a structural isomer of isoapetalic acid, friedelin, canophyllol and amentoflavone were devoid of HIV-1 RT inhibitory activity. Calanolide C was also obtained as a natural product and showed moderate inhibitory properties.
The species Ageratina pichinchensis (Asteraceae) has been used for a long time in Mexican traditional medicine for the treatment of different skin conditions and injuries. In this study, the healing capacity of the plant extracts obtained was evaluated and, in order to understand the mechanism of healing, we also analyzed its effect on cell proliferation IN VITRO, cytotoxicity, and skin irritation. Different extracts obtained from the aerial parts of A. pichinchensis, topically administrated, were evaluated in a healing model by scalpel-blade incision on the rat. The extracts, at 10 % concentrations, were administrated daily during an eight-day period. A control group, to which the vehicle was administered, was used; while fibrinolysin (Fibrase SA®) was administered for positive control purposes. Reduction in wound size and the histological characteristics of the skin at the end of the treatment were evaluated. Cytotoxicity was evaluated in cell lines KB (nasopharyngeal carcinoma), UISO (squamous cell carcinoma of the cervix), OVCAR (ovarian carcinoma), and HCT-15 (colon carcinoma). In addition, the effect on cell proliferation of cell line MRC-5 (normal cells from human fetal lung) was measured, and skin irritation was evaluated. The results showed an important healing capacity of A. pichinchensis extract in noninfected wounds; the aqueous extract was found to be the most efficient. The extracts exhibited no cytotoxic effect; however, there was an effect that promoted cell proliferation in cell line MRC-5. The products tested demonstrated no skin irritant effects.
Although significant progress has been made in the implementation of new breast cancer treatments over the last three decades, this neoplasm annually continues to show high worldwide rates of morbidity and mortality. In consequence, the search for novel therapies with greater effectiveness and specificity has not come to a stop. Among the alternative therapeutic targets, the human gonadotropin-releasing hormone type I and type II (hGnRH-I and hGnRH–II, respectively) and its receptor, the human gonadotropin-releasing hormone receptor type I (hGnRHR-I), have shown to be powerful therapeutic targets to decrease the adverse effects of this disease. In the present review, we describe how the administration of GnRH analogs is able to reduce circulating concentrations of estrogen in premenopausal women through their action on the hypothalamus–pituitary–ovarian axis, consequently reducing the growth of breast tumors and disease recurrence. Also, it has been mentioned that, regardless of the suppression of synthesis and secretion of ovarian steroids, GnRH agonists exert direct anticancer action, such as the reduction of tumor growth and cell invasion. In addition, we discuss the effects on breast cancer of the hGnRH-I and hGnRH-II agonist and antagonist, non-peptide GnRH antagonists, and cytotoxic analogs of GnRH and their implication as novel adjuvant therapies as antitumor agents for reducing the adverse effects of breast cancer. In conclusion, we suggest that the hGnRH/hGnRHR system is a promising target for pharmaceutical development in the treatment of breast cancer, especially for the treatment of advanced states of this disease.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.