Silver nanoparticles inhibit VEGF induced cell proliferation and migration in bovine retinal endothelial cells
ABSTRACT Angiogenesis, the growth of new blood vessels from pre-existing vasculature is of physiological and pathological importance. We have investigated the anti-angiogenic potential of silver nanoparticles, produced by Bacillus licheniformis. Bovine retinal endothelial cells (BRECs) were treated with the different concentrations of silver nanoparticles for 24 h in the presence and absence of vascular endothelial growth factor (VEGF), where 500 nM (IC50) of silver nanoparticle concentration, was able to block the proliferation and migration of BRECs. The cells showed a clear enhancement in caspase-3 activity and formation of DNA ladders, evidence of induction of apoptosis. Here we report for the first time that silver nanoparticles inhibit cell survival via PI3K/Akt dependent pathway in Bovine retinal endothelial cells.
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ABSTRACT: Silver nanoparticles (AgNPs) possess unique physical, chemical, and biological properties. AgNPs have been increasingly used as anticancer, antiangiogenic, and antibacterial agents for the treatment of bacterial infections in open wounds as well as in ointments, bandages, and wound dressings. The present study aimed to investigate the effects of two different sizes of AgNPs (10 nm and 20 nm) in male somatic Leydig (TM3) and Sertoli (TM4) cells and spermatogonial stem cells (SSCs). Here, we demonstrate a green and simple method for the synthesis of AgNPs using Bacillus cereus culture supernatants. The synthesized AgNPs were characterized using ultraviolet and visible absorption spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and transmission electron microscopy (TEM). The toxicity of the synthesized AgNPs was evaluated by the effects on cell viability, metabolic activity, oxidative stress, apoptosis, and expression of genes encoding steroidogenic and tight junction proteins. AgNPs inhibited the viability and proliferation of TM3 and TM4 cells in a dose- and size-dependent manner by damaging cell membranes and inducing the generation of reactive oxygen species, which in turn affected SSC growth on TM3 and TM4 as feeder cells. Small AgNPs (10 nm) were more cytotoxic than medium-sized nanoparticles (20 nm). TEM revealed the presence of AgNPs in the cell cytoplasm and nucleus, and detected mitochondrial damage and enhanced formation of autosomes and autolysosomes in the AgNP-treated cells. Flow cytometry analysis using Annexin V/propidium iodide staining showed massive cell death by apoptosis or necrosis. Real-time polymerase chain reaction and western blot analyses indicated that in TM3 and TM4 cells, AgNPs activated the p53, p38, and pErk1/2 signaling pathways and significantly downregulated the expression of genes related to testosterone synthesis (TM3) and tight junctions (TM4). Furthermore, the exposure of TM3 and TM4 cells to AgNPs inhibited proliferation and self-renewal of SSCs. Our results suggest that AgNPs exhibit size-dependent nanoreprotoxicity in male somatic cells and SSCs, strongly suggesting that applications of AgNPs in commercial products must be carefully evaluated. Further studies of AgNPs-induced nanoreprotoxicity in animal models are required.International Journal of Nanomedicine 01/2015; 10:1335-57. DOI:10.2147/IJN.S76062 · 4.20 Impact Factor
Conference Paper: Applications of Nanoparticles in OphthalmologyNanomed Conference 2014; 03/2014
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ABSTRACT: In this study, silver (Ag) nanoparticles were successfully biosynthesized from AgNO3 through a simple green route using the lichen extract [Cetraria islandica (L) Ach] as a reducing and stabilizing agent. The mean sizes of spherical Ag nanoparticles with diameters ranging from 5 nm to 29 nm were obtained at different reaction conditions. The nanoparticles were characterized using transmission electron microscopy (TEM), energy dispersive X-ray (EDX), ultraviolet-visible (UV-VIS) and Fourier transform infrared spectroscopy (FTIR) techniques. Response surface methodology (RSM) was used to investigate the effects of temperature, reaction time and AgNO3/lichen ratio on green synthesis of Ag nanoparticles. The results showed that the increase in reaction time and AgNO3/lichen ratio caused a decrease of particle size and the increase in temperature resulted in bigger particles.Green Processing and Synthesis 08/2014; 3(4). DOI:10.1515/gps-2014-0024 · 4.09 Impact Factor