title: Protection or cytotoxicity mediated by a novel quinonoid-polyphenol compound?
abstract: Many natural and synthetic quinones and naphthoquinones possess a variety of beneficial pharmacological properties. In plants, the cytotoxic properties of quinones serve in their defensive roles against invading bacteria, fungi and parasites. In this regard many quinones as well as polyphenols, exerting generally toxicity at high dosages, are able to induce favorable hormetic responses at a low dosage. The novel chloronaphthoquinone derivative of quercetin (CHNQ) showed a profound cytotoxicity followed by enhancement of intracellular generation of oxidants in human neonatal B-HNF-3 fibroblasts. Its synthetic precursors, quercetin and 2-chloro-3-hydroxy-[1,4]naphthoquinone, failed to induce these effects, and paradoxically, only CHNQ at a low concentration provided partial protection of the cells against oxidative challenge. Thus, the novel quinonoid-polyphenol CHNQ might have a merit in the search for new prospective agents in prevention and management of ageing and ageing-related pathologies.
authors.affiliation: Institute of Experimental Pharmacology and Toxicology, Slovak Academy of Sciences, Dubravska cesta 9, 841 04 Bratislava, Slovak Republic. imilackova@gmail.com.
authors.forename: Ivana
authors.initials: I
authors.lastname: Milackova
authors.forename: Lucia
authors.initials: L
authors.lastname: Rackova
authors.forename: Magdalena
authors.initials: M
authors.lastname: Majekova
authors.forename: Natasa
authors.initials: N
authors.lastname: Mrvova
authors.forename: Milan
authors.initials: M
authors.lastname: Stefek
mesh_terms: D000375:Aging; D000975:Antioxidants / Q000737:chemistry; D017209:Apoptosis; D002478:Cells, Cultured; D005419:Flavonoids / Q000737:chemistry*; D059165:Hormesis; D006801:Humans; D006861:Hydrogen Peroxide / Q000737:chemistry; D007150:Immunohistochemistry; D008958:Models, Molecular; D009285:Naphthoquinones / Q000737:chemistry*; D009336:Necrosis; D009499:Neutral Red; D016877:Oxidants / Q000737:chemistry; D018384:Oxidative Stress; D059808:Polyphenols / Q000737:chemistry*; D011809:Quinones / Q000737:chemistry*; D013778:Tetrazolium Salts; D013844:Thiazoles
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D009285:Naphthoquinones; D016877:Oxidants; D059808:Polyphenols; D011809:Quinones; D013778:Tetrazolium Salts; D013844:Thiazoles; D009499:Neutral Red; D006861:Hydrogen Peroxide; C022616:thiazolyl blue