Genotoxicity and antigenotoxicity evaluation of non‐photoactivated hypericin

Abstract

The potential genotoxicity and antigenotoxicity of non-photoactivated hypericin was investigated in five experimental models. Hypericin was non-mutagenic in the Ames assay, with and without metabolic activation. It did not exert a protective effect against mutagenicity induced by 9-aminoacridine. In a yeast (Saccharomyces cerevisiae) assay, hypericin did not increase the frequency of mitotic crossovers or total aberrants at the ade(2) locus, the number of convertants at the trp5 locus, or the number of revertants at the ilv1 locus. In combined application with 4-nitroquinoline-1-oxide, it significantly enhanced the number of revertants at the ilv1 locus at the highest concentration used. Hypericin was not mutagenic in the alga Chlamydomonas reinhardtii. However, in combined application with methyl methane sulfonate, toxicity and mutagenicity were slightly reduced. In a chromosome aberration assay using three mammalian cell lines, hypericin did not alter the frequency of structural chromosome aberrations, and in the DPPH radical scavenging assay, it did not exert any antioxidant effects.

Photoactivated hypericin is not genotoxic

“…They found out that non-photoactivated HYP was not mutagenic. In our previous paper (Miadokova et al 2010) we have shown that none of the concentrations of non-photoactivated HYP exerted mutagenic effects on strain TA97. Now we present the results of the Ames/Salmonella typhimurium assay on 3 bacterial strains (TA 97, TA 98 and TA100).…”

“…The Williams medium was supplemented with gentamicin (50 μg/ml) (Sandoz, Slovenia). The cells were cultured in plastic Petri dishes in CO 2 /air (5%: 95%) environment at 37°C, as previously described by Miadokova et al (2010).…”

“…Our study is based on our previous research aimed at the evaluation of the potential genotoxic and antigenotoxic activities of non-photoactivated HYP (Miadokova et al 2010). This work was focused on a detection of potential genotoxic effects of photoactivated HYP at the levels of primary DNA damage, gene mutations and chromosome aberrations using three different genetic test systems.…”

Breast Cancer and Current Therapeutic Approaches: From Radiation to Photodynamic Therapy

“…Among others it possesses properties suitable for PDT (Čavarga et al, 2005;Chan et al, 2009) and PDD (Thong et al, 2009). Peculiar attributes of this photosensitizer are high efficiency in production of singlet oxygen (Redmond & Gamlin, 1999) and superoxide anions after irradiation with light wavelength around 600 nm and low or no toxicity in the dark (Jacobson et al, 2001;Miadoková et al, 2009). Photoactivated HY is known to induce changes at cellular as well as vascular level or even affect CD8+ T cell-mediated cytotoxicity (Lavie et al, 2000).…”

Antimutagenic properties of several kinds of rice as tested upon yeast strainSaccharomyces cerevisiaeD7

“…For genotoxicity/antimutagenicity assay eukaryotic test system S. cereviviae D7 was used. This mutant yeast strain was constructed to simultaneous testing of toxicity, reverse mutations in ilv1 locus, mitotic crossing-over and total aberrations at the ade2 locus and mitotic gene conversion at the trp5 locus (ZIMMERMANN et al, 1984;VLCKOVA et al, 2006;MIADOKOVA et al, 2010).…”