title: In Vitro DNA-Binding, Anti-Oxidant and Anticancer Activity of Indole-2-Carboxylic Acid Dinuclear Copper(II) Complexes.
abstract: Indole-2-carboxylic acid copper complex (ICA-Cu) was successfully prepared and characterized through elemental analysis, IR, UV-Vis, ¹H-NMR, TG analysis, and molar conductance, and its molecular formula was [Cu₂(C₉H₆O₂N)₄(H₂O)₂]·2H₂O. The binding ability of ICA-Cu to calf thymus DNA (CT-DNA) was examined by fluorescence spectrometry and the viscosity method. The results indicated that, upon the addition of increasing amounts of CT-DNA, the excitation and emission intensity of ICA-Cu decreased obviously and the excitation spectra shifted towards a long wavelength. ICA-Cu could displace ethidium bromide (EB) from the EB-DNA system, making the fluorescence intensity of the EB-DNA system decrease sharply; the quenching constantKSVvalue was 3.99 × 10⁴ M-1. The emission intensity of the ICA-Cu-DNA system was nearly constant, along with the addition of Na⁺ in a series of concentrations. The fluorescence of the complex could be protected after the complex interacted with DNA. A viscosity measurement further supported the result that the ICA-Cu complex may interact with DNA in an intercalative binding mode. The antioxidant activities of ICA-Cu were evaluated by a 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, a hydroxyl radical (OH) scavenging assay, and a 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) assay. The ICA-Cu exhibited the highest inhibitory effects on the ABTS radical (94% inhibition at 60 µM), followed by OH and DPPH radicals (the degrees of inhibition being 71% and 56%, respectively). The in vitro cytotoxicity activity of ICA-Cu against two human breast cancer cell lines, MDA-MB-231 and MCF-7, was investigated by 3-[4,5-dimethyltiazol2-yl]-2.5-diphenyl-tetrazolium bromide (MTT) assay and cellular morphological analysis. The results showed that, upon increasing the concentration of ICA-Cu, an increase was observed in growth-inhibitory activity and the inhibition percentage were greater than 90% at 20 µM in both cell lines. Also, cellular morphological changes in the two cell lines agreed with the cytotoxicity results.
authors.affiliation: School of Pharmacy, Jining Medical University, 669 Xueyuan Road, Rizhao 276800, Shandong, China. wxcwayne@126.com.
authors.forename: Xiangcong
authors.initials: X
authors.lastname: Wang
authors.affiliation: School of Pharmacy, Jining Medical University, 669 Xueyuan Road, Rizhao 276800, Shandong, China. yanmaocai@126.com.
authors.forename: Maocai
authors.initials: M
authors.lastname: Yan
authors.affiliation: School of Pharmacy, Jining Medical University, 669 Xueyuan Road, Rizhao 276800, Shandong, China. 18263372608@163.com.
authors.forename: Qibao
authors.initials: Q
authors.lastname: Wang
authors.affiliation: School of Pharmacy, Jining Medical University, 669 Xueyuan Road, Rizhao 276800, Shandong, China. wanghuannan0322@126.com.
authors.forename: Huannan
authors.initials: H
authors.lastname: Wang
authors.affiliation: School of Pharmacy, Jining Medical University, 669 Xueyuan Road, Rizhao 276800, Shandong, China. 17806217108@163.com.
authors.forename: Zhengyang
authors.initials: Z
authors.lastname: Wang
authors.affiliation: School of Pharmacy, Jining Medical University, 669 Xueyuan Road, Rizhao 276800, Shandong, China. 17806218007@163.com.
authors.forename: Jiayi
authors.initials: J
authors.lastname: Zhao
authors.affiliation: School of Pharmacy, Jining Medical University, 669 Xueyuan Road, Rizhao 276800, Shandong, China. 17862335612@163.com.
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.affiliation: School of Pharmacy, Jining Medical University, 669 Xueyuan Road, Rizhao 276800, Shandong, China. zhangzhen_1029@126.com.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D001943:Breast Neoplasms / Q000188:drug therapy*; D002264:Carboxylic Acids; D002417:Cattle; D045744:Cell Line, Tumor; D003300:Copper / Q000737:chemistry*; D004247:DNA / Q000378:metabolism; D004996:Ethidium / Q000378:metabolism; D006801:Humans; D007211:Indoles / Q000737:chemistry* / Q000494:pharmacology*; D061986:MCF-7 Cells
chemical_list: D000975:Antioxidants; D002264:Carboxylic Acids; D007211:Indoles; C058980:indole-2-carboxylic acid; D003300:Copper; D004247:DNA; C427203:calf thymus DNA; D004996:Ethidium
keywords: DNA-binding; anticancer; antioxidant; copper(II) complexes; indole-2-carboxylicacid