Use of Hypericin in Clinical Trials of Photodynamic Therapy

Hypericin is derived from St. John's wort and is a potent, naturally occurring photosensitizer used in photodynamic therapy (PDT) to treat cancer. PDT is based on the induction of a photochemical reaction between a non-toxic photosensitizer, light, and oxygen. In this technique, after systemic administration of a photosensitizing agent (PS), local necrosis of neoplastic cells, inflammatory lesions, or cells of microorganisms such as bacteria, viruses, and fungi are induced using light of a specific wavelength. The use of PDT allows a limited number of surgical procedures and often completes the treatment process. Hypericin is a potential clinical antitumor agent, as many studies have demonstrated its potent antitumor activity in vi-vo and in vitro after irradiation. This photosensitizer can induce apoptosis and necrosis depending on the concentration and dose of light. This article aims to provide a general overview of the use of hypericin in clinical trials of PDT therapy. The literature was searched for articles relevant to the topic of this review using the PubMed, Scopus, ScienceDirect, and Google Scholar databases using the following keywords: "Hypericin", "Photodynamic therapy," and “Nutrients”. The literature reviewed relies on the use of hypericin in PDT. Studies of photodynamic effects using hypericin may be helpful in the clinical search for the best treatments for skin cancer lesions, mainly in the youngest patients.