Cytotoxic effect of Salvadora persica extracts on human gingival fibroblast cells.

Objectives: To assess the cytotoxic potential of Salvadora persica (S. persica) extracts on human gingival fibroblast (HGF) cells.

Methods: This study was conducted between January and May 2012 in collaboration with Dental Caries Research Chair, College of Dentistry, King Saud University, Riyadh, Saudi Arabia. Extracts of S. persica using hexane, ethylacetate, and ethanol as solvents at concentrations of 0.5 mg/ml and 1 mg/ml were evaluated for their cytotoxic activity against HGFs using the 3 cytotoxic assays: (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, a tetrazole) (MTS), lactic dehydrogenase (LDH), and crystal violet (CV). International standards for the evaluation of medical materials recommended cut-off value of cell survival >70% was used for interpretation of the results.

Results: Ethanol extract of S. persica at 0.5 mg/ml and 1 mg/ml and hexane extract of S. persica at 0.5 mg/ml were completely devoid of cytotoxic activity, hexane extract at 1 mg/ml in comparison with controls  demonstrated some cytotoxicity with cell survival of 88% (p=0.045) in MTS, 86% (p=0.01) in LDH, and 88% (p=0.002) in CV assays. Similarly, ethyl acetate extract of S. persica at 0.5 mg/ml maintained cell viability of 91% in MTS, 81% in LDH, and 80% in CV assays. Maximum cytotoxicity against HGFs was observed with ethyl acetate extract of S. persica at 1 mg/ml with cell survival of 60% in MTS, 40% in LDH, and 66% CV assays (p=0.0001).  

Conclusion: The acceptable level of cytotoxicity associated with S. persica ethanol and hexane extracts requires further evaluation to be used as irrigation solutions in endodontic treatment.