Effect of Arrabidaea chica verlot ethanolic extract on epithelial cells viability exposed to a bisphosphonate
Bisphosphonates alter bone and oral epithelial cells growth and proliferation. Arrabidaea chica (H&B.) Verlot is a common tropical American plant with a wound healing activity previously described. This study aimed the evaluation of A.chica extract effect on the viability of human keratinocytes (HaCat) previous or after exposure to Zoledronic Acid (ZA). Cells (3×104cel/mL, RPMI/FBS 5%, 100µL/well) in 96-well plate were incubated (37°C, 5%CO2). After 24h, they were submitted to ZA (10µM) or A.chica (AC; 50, 100 or 150µg/mL) treatment, both in RPMI/FBS 0.3%. After another 24h, these treatments were switched and cells were incubated for 48h. Cells were fixed with 50% Trichloroacetic acid and had their viability determined by Sulforhodamine B method. All experiments were done in triplicate and 3 plates, for each incubation period, used for comparison of the results. Data was expressed as media±SD. HaCat cells exposed to ZA for 72h had shown 31.9%(±4.4) of cell viability. AC treatment previously to ZA resulted on cell viability of 79.4%(±7.7), 88.2%(±0.5) and 94%(±4.3) whereas AC treatment after 24h ZA exposition promoted a viability of 30.4%(±4.3), 23.7%(±1.0), 35.8%(±19.8), respectively to 50, 100 and 150µg/mL of AC. These data showed that A. chica extract treatment of epithelial cells previously to ZA exposure was able to protect these cells against the harmful effects of this bisphosphonate.