Pharmacological effects and toxicity of Costus pulverulentus C. Presl (Costaceae)

Costus pulverulentus C. Presl (Costaceae), a species endemic to Mexico, is used for the empirical treatment of cancer, pain, and inflammation.

The objective of this study was to evaluate the toxicity, as well as the cytotoxic, antinociceptive, anti-inflammatory and sedative effects of an ethanol extract from Costus pulverulentus stem (CPE).

The chemical characterization of CPE was performed by Gas chromatography-mass spectrometry (GC-MS). The toxicity of CPE was evaluated using the comet assay (10-1000 µg/ml during 5h) and the acute toxicity test (500-5000 mg/kg p.o. and i.p. during 14 days). The cytotoxic effect of CPE (1-250 µg/ml) on human cancer cells was evaluated using the MTT assay. The antinociceptive effects of CPE (50-200mg/kg p.o.) were evaluated using thermal-induced nociception tests (hot plate and tail flick) and the chemical-induced nociceptive tests (acetic acid and formalin). The sedative activity of CPE (50-200mg/kg p.o.) was evaluated using the ketamine-induced sleeping time test.

CPE showed the presence of compounds such as campesterol, stigmasterol β-sitosterol, vanillic acid, among others. In the comet assay, CPE at 200 µg/ml or higher concentrations induced DNA damage. In the acute toxicity test, the LD50 estimated for CPE was>5000 mg/kg p.o. or i.p. CEP showed moderate cytotoxic effects on prostate carcinoma cells PC-3 cells (IC50=179 ± 23.2 µg/ml). In the chemical-induced nociception models, CPE (100 and 200mg/kg p.o.) showed antinociceptive effects with similar activity to 100mg/kg naproxen. In the thermal-induced nociception tests, CPE tested at 200mg/kg showed moderate antinociceptive effects by 28% (hot plate test) and by 25% (tail flick test). In the ketamine-induced sleeping time test, CPE showed no sedative effects.

C. pulverulents exerts moderate cytotoxic effects in human cancer cells, moderate anti-inflammatory and antinociceptive effects. C. pulverulentus induces antinociceptive effects without inducing sedation.