title: Gold Nanoparticles of Diameter 13 nm Induce Apoptosis in Rabbit Articular Chondrocytes.
abstract: Gold nanoparticles (AuNPs) have been widely used in biomedical science including antiarthritic agents, drug loading, and photothermal therapy. In this report, we studied the effects of AuNPs with diameters of 3, 13, and 45 nm, respectively, on rabbit articular chondrocytes. AuNPs were capped with citrate and their diameter and zeta potential were measured by dynamic light scattering (DLS). Cell viability was evaluated by Cell Counting Kit-8 (CCK-8) assay after the rabbit articular chondrocytes were pre-incubated with 3, 13, and 45 nm AuNPs, respectively, for 24 h. Flow cytometry (FCM) analysis with annexin V/propidium iodide (PI) double staining and fluorescence imaging with Hoechst 33258 staining were used to determine the fashion of AuNPs-induced chondrocyte death. Further, 13 nm AuNPs (2 nM) significantly induced chondrocyte death accompanying apoptotic characteristics including mitochondrial damage, externalization of phosphatidylserine and nuclear concentration. However, 3 nm AuNPs (2 nM) and 45 nm (0.02 nM) AuNPs did not induce cytotoxicity in chondrocytes. Although 13 nm AuNPs (2 nM) increased the intracellular reactive oxygen species (ROS) level, pretreatment with Nacetyl cysteine (NAC), a ROS scavenger, did not prevent the cytotoxicity induced by 13 nm AuNPs, indicating that 13 nm AuNPs (2 nM) induced ROS-independent apoptosis in chondrocytes. These results demonstrate the size-dependent cytotoxicity of AuNPs in chondrocytes, which must be seriously considered when using AuNPs for treatment of osteoarthritis (OA).
authors.affiliation: Department of Pain Management, The First Affiliated Hospital of Jinan University, Guangzhou, 510630, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Huang
authors.affiliation: Department of Pain Management, The First Affiliated Hospital of Jinan University, Guangzhou, 510630, China.
authors.forename: Ying-Yao
authors.initials: YY
authors.lastname: Quan
authors.affiliation: Department of Pain Management, The First Affiliated Hospital of Jinan University, Guangzhou, 510630, China. txp2938@jnu.edu.cn.
authors.forename: Xiao-Ping
authors.initials: XP
authors.lastname: Wang
authors.affiliation: MOE Key Laboratory of Laser Life Science and College of Biophotonics, South China Normal University, Guangzhou, 510006, China.
authors.forename: Tong-Sheng
authors.initials: TS
authors.lastname: Chen
keywords: Chondrocyte apoptosis; Gold nanoparticles; Osteoarthritis; Size-dependent cytotoxicity