Cytotoxic Effects of Indonesian Betel Quid Components on Oral Keratinocytes and Fibroblasts

Abstract

A betel quid (BQ) chewing habit has been strongly associated with the development of several oral mucosal diseases. In order to investigate whether individual components of BQ mixtures have distinct physio-pathological effects on oral mucosal cells, we examined the impact of areca nut (AN), Piper betle leaf (Leaf), Piper betle stem inflorescence (SI), areca husk (Husk) and the complete BQ mixture on the growth of oral keratinocytes (OKF-6) and primary oral fibroblasts (MMF-1). Based on their known chemical properties, we selected BQ samples from Banda Aceh (BA) and West Papua (WP) regions for our in vitro study. We used a fluorescein diacetate assay (FDA) to assess the cell viability of BQ components on OKF-6 and MMF-1 cells. The cytotoxic effect of WP-AN on the OKF-6 cell line was observed at a concentration of 100 μg/mL, resulting in a 50% reduction in cell viability (IC50) after a 2-day incubation. Similarly, BA-AN exhibited cytotoxic effect, although at a higher concentration (500 μg/mL). WP-SI also displayed cytotoxic effects at a concentration of 500 μg/mL following 2 days of incubation. In contrast, Leaf, BQ mixture and husk extracts did not show any cytotoxic effects even after 3 days of incubation. No cytotoxic effects were observed at any concentration of BQ components when exposed to MMF-1 cells. Regarding cell proliferation, MMF-1 cells exposed to BA-AN and WP-AN showed increased growth on day 1, followed by decreased growth on day 2, in a dose- and time-dependent manner. Overall, our study indicates that BQ components induce distinctive cytotoxic effects on stromal and epithelial cells from the oral cavity.