Silver nanoparticles do not influence stem cell differentiation but cause minimal toxicity

Center for Chemical Toxicology Research & Pharmacokinetics, North Carolina State University, NC, USA.
Nanomedicine (Impact Factor: 5.82). 05/2012; 7(8):1197-209. DOI: 10.2217/nnm.12.18
Source: PubMed

ABSTRACT To evaluate the toxicity and cellular uptake of both undifferentiated and differentiated human adipose-derived stem cells (hASCs) exposed to silver nanoparticles (Ag-NPs), and to assess their effect on hASC differentiation.
hASC were exposed to 10- or 20-nm Ag-NPs at concentrations of 0.1, 1.0, 10.0, 50.0 and 100.0 µg/ml either before or after differentiation down the adipogenic or osteogenic pathways.
Exposure of hASC to either 10- or 20-nm Ag-NPs resulted in no significant cytotoxicity to hASC, and minimal dose-dependent toxicity to adipogenic and osteogenic cells at 10 µg/ml. Each of the hASC, adipogenic and osteogenic cells showed cellular uptake of both 10- and 20-nm Ag-NPs, without causing significant ultrastructural alterations. Exposure to 10- or 20-nm Ag-NPs did not influence the differentiation of the cells, and at antimicrobial concentrations of Ag-NPs resulted in a minimal decrease in viability.
The biocompatibility of Ag-NPs with both undifferentiated and differentiated hASC establishes their suitability for incorporation into tissue-engineered graft scaffolds, for the prevention of bacterial contamination upon implantation.

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Available from: Nancy A Monteiro-Riviere, Aug 30, 2015
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    • "Silver is a potent antimicrobial agent with broad-spectrum antimicrobial activity against Gram-negative and Gram-positive bacteria, fungi, and certain viruses, including antibiotic-resistant strains,11 less likelihood of developing resistant strains, and has been used safely in medicine for many years.12–14 For improved antibacterial activity at the nanoscale level, silver nanoparticles (AgNPs) are becoming the most useful and valuable nanomaterial in medicine.9 A number of investigators have reported the use of AgNPs in tissue engineering scaffolds, with a reduced incidence of infection and good cell compatibility.15,16 "
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    International Journal of Nanomedicine 05/2014; 9(1):2469-2478. DOI:10.2147/IJN.S59753 · 4.38 Impact Factor
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    • "In all, with contradictory findings reported, there is at present no general agreement on the in vitro toxicity of AgNPs. A study by Hackenberg et al. [8] reported reduced cell viability at a AgNP dose of 10 μg/mL (1 h exposure, AgNPs <50nm) in human mesenchymal stem cells, whereas Samberg et al. [9] showed no toxicity for progenitor human adipose-derived stem cells up to 100 μg/mL (10 and 20 nm AgNPs for 24 h, and then differentiated for 14 days). Also, the stability and aging of AgNPs have been reported to be important for the toxicological outcome. "
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    • "Silver in the form of nanoparticles has been incorporated in nanofibers by either in situ generation of nanoparticles within the polymer [18] [19] [20] or by dispersion of prepared nanoparticles in the system (ex situ synthesis ) [21] [22]. However, the very small size of nanoparticles allows them to penetrate into the stratum corneum of skin [23] [24] or diffuse within the cellular plasma membrane and interfere with a variety of cellular mechanisms [22] [25]. For this reason, in recent years, the FDA and others [26] [27] [28] have recently expressed concern over antimicrobial approaches incorporating silver nanoparticles. "
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