Clinacanthus nutans (C. nutans), a well-known ethnopharmacological plant consumed for its medicinal purposes by Southeast Asian communities. C. nutans is said to possess antipyretic, inflammatory, antiedemic as well as analgesic properties and used traditionally in treating various skin ailments, Herpes infection, cancer and diabetes. The young leaves of this C. nutans are consumed in Malaysia for maintaining health. In this study, the proliferative activity of human gingival fibroblast cells (HGF-1, ATCC®CRL-2014™, USA) treated with the ethanol extract obtained from C. nutans leaves at three different concentrations (250, 125 and 62.5 µg/ml) was compared with the untreated cells using alamarBlue assay. The proliferative activity of HGF-1 using alamarBlue assay showed that the cells treated with 62.5 μg/ml of ethanolic extract of C. nutans leaves exhibited increased proliferation compared to the other groups and hence does not exhibit any cytotoxicity on HGF-1.
The aim of this study was to determine the genotoxicity of a locally produced nanocomposite by Universiti Sains Malaysia, Malaysia using Comet assay. Stem cells from human exfoliated deciduous teeth (SHED) were treated with the nanocomposite at five different concentrations (0.006, 0.0125, 0.025, 0.05, and 0.1 mg/ml) along with concurrent negative (medium alone) and positive control (zinc sulfate heptahydrate) and incubated at 37°C for 24 hours in an incubator at 5% CO2. The tail moment was used to assess the extent of DNA damage. The tail moment for the group of SHED treated with nanocomposite (for all the five different concentrations) was not statistically significant as compared to the negative control, suggesting that the locally produced dental nanocomposite did not induce any DNA damage. Hence, it can be concluded that the locally produced nanocomposite is non-genotoxic on stem cells from human exfoliated deciduous teeth.