Interaction between dental metals and antioxidants, assessed by cytotoxicity assay and ESR spectroscopy.
Among dental metals, copper showed the highest cytotoxicity against human oral squamous cell carcinoma and human submandibular gland carcinoma cells, followed by palladium-alloy, gold and silver. Normal human cells (gingival fibroblast, pulp cells, periodontal ligament fibroblast) were relatively resistant to these metals. The palladium-alloy failed to induce internucleosomal DNA fragmentation, a biochemical hallmark of apoptosis, in human promyelocytic leukemic HL-60 cells. The cytotoxic activity of the palladium-alloy was significantly reduced by a non-cytotoxic concentration of N-acetyl-L-cysteine, or more efficiently by sodium ascorbate. However, higher concentrations of sodium ascorbate enhanced the cytotoxic activity of palladium-alloy. ESR spectroscopy showed that the palladium-alloy enhanced the intensity of ascorbate radical, suggesting the possible interaction between metals and antioxidants. All metals, except copper, did not significantly affect the generation of superoxide anion (by hypoxanthine-xanthine oxidase reaction), hydroxyl radical (by Fenton reaction) and nitric oxide (from NOC-7 in the presence of C-PTIO). These data demonstrate for the first time that antioxidants modify the biological activity of dental metals.
Kinoshita
Naoto
N
Department of Operative Dentistry, Meikai University School of Dentistry, Saitama, Japan. sakagami@dent.meikai.ac.jp
Yamamura
Takahiko
T
Teranuma
Hiroshi
H
Katayama
Tadashi
T
Tamanyu
Mikako
M
Negoro
Takaharu
T
Satoh
Kazue
K
Sakagami
Hiroshi
H
D000975:Antioxidants / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000494:pharmacology; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy; D003300:Copper / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D003764:Dental Materials / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D004347:Drug Interactions; D004578:Electron Spin Resonance Spectroscopy; D005347:Fibroblasts / Q000187:drug effects; D005609:Free Radicals / Q000737:chemistry / Q000378:metabolism; D005881:Gingiva / Q000166:cytology / Q000187:drug effects; D006046:Gold / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D018922:HL-60 Cells / Q000187:drug effects; D006801:Humans; D019271:Hypoxanthine / Q000737:chemistry / Q000378:metabolism; D008670:Metals / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D009062:Mouth Neoplasms / Q000188:drug therapy; D010165:Palladium / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D010513:Periodontal Ligament / Q000166:cytology / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000737:chemistry / Q000378:metabolism; D012834:Silver / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D013365:Submandibular Gland Neoplasms / Q000188:drug therapy; D014407:Tumor Cells, Cultured; D014969:Xanthine Oxidase / Q000737:chemistry / Q000378:metabolism
D000975:Antioxidants; D003764:Dental Materials; D005609:Free Radicals; D008670:Metals; D017382:Reactive Oxygen Species; D019271:Hypoxanthine; D012834:Silver; D010165:Palladium; D006046:Gold; D003300:Copper; D014969:Xanthine Oxidase; D001205:Ascorbic Acid