Anti-inflammatory, cytotoxic and morphological impact of phycocyanin on ultraviolet radiation irradiated human fibroblast cells.

Background: Recently, the use of natural products as skin photoprotective agents has been in increasing demand. This study investigated the bioactivity of phycocyanin (PC) extracted from Spirulina sp. on human skin fibroblast cell line (CCD-966SK), specifically focusing on apoptosis, necrosis, anti-inflammatory effects, and enzymatic reactions.

Methods: The first step of this study was cyanobacterial cell culture and the extraction and purification of PC. After that, CCD-966SK cell line was cultivated under normal and UV irradiation. The bioassays included the cytotoxicity measurement, cell viability assay, morphology determination, tumour necrosis factor-α and Interleukin 6 release assays, enzyme activity for superoxide dismutase and glutathione peroxidase as well as malondialdehyde content and the cell-free extract of cyanobacterial stains were assessed.

Results: The cell viability results showed that as the concentration of the PC increased, the viability of CCD-966SK cell line was reduced, which suggested that the effect of PC on the growth of fibroblast cells was dose dependent. The morphological results indicated that presence of PC in the fibroblast cell culture medium led to a transformation in cell morphology from spindle-shaped to spherical. PC released anti-inflammatory IL-6 and TNF-a cytokines, indicating high inflammation resistance. Furthermore, the findings revealed that PC dramatically reduced the release of superoxide dismutase, glutathione peroxidase, and malondialdehyde from inflammatory cells, with the reduction being more apparent at increasing doses.

Conclusions: In conclusion, the results indicated that PC inhibit the CCD-966SK cell line by membrane destructor, which led to the increase the leakage of cell constituent and increase enzymes activities.