Cytotoxicity of Silver Nanoparticle and Chitin-Nanofiber Sheet Composites Caused by Oxidative Stress

Abstract

Size-controlled spherical silver nanoparticles (<10 nm) and chitin-nanofiber sheet composites (Ag NPs/CNFS) have previously been reported to have strong antimicrobial activity in vitro. Although Ag NPs/CNFS have strong antimicrobial activity, their cytotoxicity has not been investigated. This study was performed to evaluate the effects of Ag NPs/CNFS on cytotoxicity for fibroblasts in vitro and healing delay of wound repair in vivo, focused on oxidative stress. Cytotoxic activities of Ag NPs/CNFS were investigated using a fibroblast cell proliferation assay, nitric oxide/nitrogen dioxide (NO/NO2) measurement of the cell lysates in vitro, inhibitory effects of Ag NPs/CNFS on healing-impaired wound repair using diabetic mice in vivo, 8-hydroxy-2′-deoxyguanosine (8-OHdG) immunohistochemical staining of the skin sections, and generation of carbonyl protein in the wound was performed to evaluate cytotoxicity with oxidative stress. Ag NPs/CNFS exhibited cytotoxicity for fibroblasts and a significant increase of total NO/NO2 levels in the cell lysates in vitro and increased levels of 8-OHdG and carbonyl proteins in vivo. Although wound repair in the continuously Ag NPs/CNFS-treated group was delayed, it could be mitigated by washing the covered wound with saline. Thus, Ag NPs/CNFS may become accepted as an anti-infectious wound dressing.

Protective effect of FGF-2 and low-molecular-weight heparin/protamine nanoparticles on radiation-induced healing-impaired wound repair in rats

“…For further histological observation, 8-OHdG immunohistochemical staining of skin sections at 24 h after wound creation was performed to measure the 8-OHdG–positive spots. The 8-OHdG staining indicates the hyperoxidation state of the nucleic acids, allowing the anti-oxidative effect to be evaluated [ 10 , 25 ]. We found 8-OHdG–positive staining at the wound surface in both the X-irradiated FGF-2&LMWH/P NPs and control groups (Fig.…”

Skin Cleansing Technique with Disinfectant using Improved High-Velocity Steam-Air Micromist Jet Spray

“…of wound healing and with the higher concentrations required for disinfectant activity, compared to BiSCaO, NaClO, and HClO (Kinoda et al, 2016;McCauley et al, 1989;Wiegand et al, 2015) . Therefore, a topical disinfectant that can decrease the bacterial bioburden of chronic wounds without inhibiting the wound healing process is a therapeutic imperative.…”

“…to the cellular components for wound healing (Wiegand et al, 2015) , since higher concentrations are required for bactericidal activity (Kinoda et al, 2016;McCauley et al, 1989) . This has led to the current use of various disinfectants such as silver nanoparticles (Ishihara et al, 2015;Nguyen et al, 2014;Mori et al, 2011) , bio-shell calcium oxides (BiSCaO) powder, hypochlorous acid (HClO) , and sodium hypochlorite (NaClO) , based on their bactericidal properties with relatively low concentrations.…”

Evaluation of immunoresponses and cytotoxicity from skin exposure to metallic nanoparticles

“…81 Many reports have shown that metallic NPs can significantly enhance the formation of ROS in skin cells. 8,82,83 Increased NO/ NO 2 and decreased GPx in fibroblasts and HaCaT cells have been observed after exposure to metallic NPs, indicating that NPs caused inflammatory responses and metabolic changes. Additionally, NPs affected the gene expression of SOD and GPx.…”

“…Meanwhile, decreased GPx led to a reduction in toxic peroxides in cells. 16,68,82 Similarly, an in vitro study showed that oxidative stress was the key cause of mitochondrial membrane damage, cell-cycle arrest, and DNA damage after mouse-skin fibroblast cells had been exposed to MoNPs. 84 The secondary effect of ROS caused the activation of cell-death-mediated signaling via NFκB.…”