Conclusion
All in all, we have confirmed that undifferentiated callus extracts of S. marianum possess properties such as antioxidant and anti-inflammatory activities in both normal and malignant keratinocytes, and thus could be a promising agent controlling the pro-inflammatory IL-6 production.
Methods
Antioxidant activity of the extracts was analyzed by using the Trolox Equivalent Antioxidant Capacity (TEAC) assay. High-Performance Thin-Layer Chromatography (HPTLC) was performed to demonstrate the phytochemical profile, and the total flavonoid content was analyzed with an aluminum chloride colorimetric method. The anti-inflammatory effect was investigated by cell treatments using the plant extracts. Thereafter, the possible suppression of induced IL-6 response was measured from the cultured skin cancer cell lines A2058 and A431, and normal primary keratinocytes with Enzyme-Linked Immunosorbent Assay (ELISA).
Results
The HPTLC analysis assessed that the extracts contained a complex phytochemical profile that was rich in phenolic and flavonoid compounds. Dose response assays showed that concentrations between 15 and 125 μg/mL of all three plant extracts could be used to investigate an effect on the IL-6 production. The S. marianum extract had the most pronounced anti-inflammatory effect, which significantly inhibited induced IL-6 production in both normal keratinocytes and skin cells derived from epidermal carcinoma. The extract from S. marianum also had the highest flavonoid content and showed the highest antioxidant activity of the three extracts tested.