Comparison of liposomal and 2-hydroxypropyl-beta-cyclodextrin-lidocaine on cell viability and inflammatory response in human keratinocytes and gingival fibroblasts

Objectives The aim of this study was to observe the effect multilamellar liposomes (MLV) and 2-hydroxypropyl-beta-cyclodextrin (HP-beta-CD) in the in-vitro effects of lidocaine in cell viability, pro-inflammatory cytokines and prostaglandin E-2 release of both human keratinocytes (HaCaT) and gingival fibroblasts (HGF) cells. Methods HaCaT and HGF cells were exposed to lidocaine 100-1 mu M in plain, MLV and HP-beta-CD formulations for 6 h or 24 h. The formulation effects in cell viability were measured by XTT assay and by fluorescent labelling. Cytokines (IL-8, IL-6 and TNF-alpha) and PGE(2) release were quantified by ELISA. Key findings MLV and HP-beta-CD formulations did not affect the HaCaT viability, which was significantly decreased by plain lidocaine after 24 h of exposure. Both drug carriers increased all cytokines released by HGF after 24-h exposure, and none of the carriers was able to reduce the PGE(2) release induced by lidocaine. Conclusion The effect of drug carrier in the lidocaine effects was dependent on the cell type, concentration and time of exposure. MLV and HP-beta-CD showed benefits in improving cell viability; however, both of them showed a tendency to increase cytokine release when compared to the plain solution. (AU)