Hypericum perforatum L. subsp. perforatum induces inhibition of free radicals and enhanced phototoxicity in human melanoma cells under ultraviolet light

Cell Prolif. 2013 Apr;46(2):193-202. doi: 10.1111/cpr.12020.

Abstract

Objectives: Our interest continues in discovering phytocomplexes from medicinal plants with phototoxic activity against human melanoma cells; thus the aim of the present study was to assess antioxidant, anti-inflammatory and phototoxic activity of Hypericum perforatum L. subsp. perforatum, and relate these properties to the plant's chemical composition.

Materials and methods: Components of H. perforatum subsp. perforatum were extracted by hydroalcoholic solution and chemical profiles of preparations (HyTE-3) performed by HPTLC. Linoleic acid peroxidation and DPPH tests were used to assess antioxidant activity, while MTT assay allowed evaluation of anti-proliferative activity with respect to A375 human melanoma cells after irradiation with UVA dose, 1.8 J/cm(2) . Inhibition of nitric oxide production of macrophages was also investigated.

Results: HyTE-3 indicated better antioxidant activity with β-carotene bleaching test in comparison to DPPH assay (IC50 = 0.89 μg/ml); significant phototoxicity in A375 cells at 78 μg/ml concentration resulted in cell destruction of 50%. HyTE-3 caused significant dose-related inhibition of nitric oxide production in murine monocytic macrophage cell line RAW 264.7 with IC50 value of 342 μg/ml.

Conclusions: The H. perforatum subsp. perforatum-derived product was able to suppress proliferation of human malignant melanoma A375 cells; extract together with UVA irradiation enhanced phototoxicity. This biological activity of antioxidant effects was combined with inhibition of nitric oxide production.

MeSH terms

  • Animals
  • Anti-Inflammatory Agents, Non-Steroidal / chemistry
  • Anti-Inflammatory Agents, Non-Steroidal / pharmacology
  • Antineoplastic Agents, Phytogenic / chemistry
  • Antineoplastic Agents, Phytogenic / pharmacology
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Free Radical Scavengers / chemistry*
  • Free Radical Scavengers / pharmacology
  • Free Radicals / chemistry*
  • Humans
  • Hypericum / chemistry*
  • Inhibitory Concentration 50
  • Macrophages / chemistry
  • Macrophages / pathology
  • Melanoma / chemistry
  • Melanoma / pathology
  • Mice
  • Nitric Oxide / chemistry
  • Phenols / chemistry
  • Photosensitizing Agents / chemistry
  • Photosensitizing Agents / pharmacology
  • Plant Components, Aerial / chemistry
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology
  • Ultraviolet Rays*
  • beta Carotene / pharmacology

Substances

  • Anti-Inflammatory Agents, Non-Steroidal
  • Antineoplastic Agents, Phytogenic
  • Free Radical Scavengers
  • Free Radicals
  • Phenols
  • Photosensitizing Agents
  • Plant Extracts
  • beta Carotene
  • Nitric Oxide