Sphaeralcea angustifolia (Cav.) G. Don extract, a potential phytomedicine to treat chronic inflammation

Biological properties of Sphaeralcea angustifolia have recently attracted attention because of the potential that this Mexican medicinal plant has as a remedy to treat inflammation. The dichloromethane extract of the plant's aerial parts inhibits pro-inflammatory molecules such as Interleukin (IL)-1, Tumor necrosis factor (TNF)-α, and IL-6 with a maximum expression in the late phase, an effect that is consistent with the findings in the present study, which showed that in rats with induced chronic inflammation by means of Complete Freund's adjuvant (CFA), the extract (100 mg/kg per day for 8 days) produced a sustained and significant inhibition of the edema (62.6%). Topical application of the dichloromethane extract produced ear edema reduction (50.6%) and a protective effect against 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced mouse ear irritation. Active fractions contain β-sitosterol, stigmasterol, α and β-amyrins, transcinnamic acid, and scopoletin, with scopoletin the main constituent found in the more active fraction of the extract. The results obtained here demonstrated both the systemic and topic effects of S. angustifolia on experimental chronic-inflammation models with no evidence of toxic effects of the extract.