Molecular Biocompatibility of a Silver Nanoparticle Complex with Graphene Oxide to Human Skin in a 3D Epidermis In Vitro Model.

Silver nanoparticles (AgNP) can migrate to tissues and cells of the body, as well as to agglomerate, which reduces the effectiveness of their use for the antimicrobial protection of the skin. Graphene oxide (GO), with a super-thin flake structure, can be a carrier of AgNP that stabilizes their movement without inhibiting their antibacterial properties. Considering that the human skin is often the first contact with antimicrobial agent, the aim of the study was to assess whether the application of the complex of AgNP and GO is biocompatible with the skin model in in vitro studies. The conducted tests were performed in accordance with the criteria set in OECD TG439. AgNP-GO complex did not influence the genotoxicity and metabolism of the tissue. Furthermore, the complex reduced the pro-inflammatory properties of AgNP by reducing expression of IP-10 (interferon gamma-induced protein 10), IL-3 (interleukin 3), and IL-4 (interleukin 4) as well as MIP1ß (macrophage inflammatory protein 1ß) expressed in the GO group. Moreover, it showed a positive effect on the micro- and ultra-structure of the skin model. In conclusion, the synergistic effect of AgNP and GO as a complex can activate the process of epidermis renewal, which makes it suitable for use as a material for skin contact.

Graphene Oxide Scaffold Stimulates Differentiation and Proangiogenic Activities of Myogenic Progenitor Cells.

The physiological process of muscle regeneration is quite limited due to low satellite cell quantity and also the inability to regenerate and reconstruct niche tissue. The purpose of the study was to examine whether a graphene oxide scaffold is able to stimulate myogenic progenitor cell proliferation and the endocrine functions of differentiating cells, and therefore, their active participation in the construction of muscle tissue. Studies were carried out using mesenchymal cells taken from 6-day-old chicken embryos and human umbilical vein endothelial cells (HUVEC) were used to assess angiogenesis. The graphene scaffold was readily colonized by myogenic progenitor cells and the cells dissected from heart, brain, eye, and blood vessels did not avoid the scaffold. The scaffold strongly induced myogenic progenitor cell signaling pathways and simultaneously activated proangiogenic signaling pathways via exocrine vascular endothelial growth factor (VEGF) secretion. The present study revealed that the graphene oxide (GO) scaffold initiates the processes of muscle cell differentiation due to mechanical interaction with myogenic progenitor cell.

Graphene oxide nanofilm and the addition of L-glutamine can promote development of embryonic muscle cells.

BACKGROUND: Formation of muscular pseudo-tissue depends on muscle precursor cells, the extracellular matrix (ECM)-mimicking structure and factors stimulating cell differentiation. These three things cooperate and can create a tissue-like structure, however, their interrelationships are relatively unknown. The objective was to study the interaction between surface properties, culture medium composition and heterogeneous cell culture. We would like to demonstrate that changing the surface properties by coating with graphene oxide nanofilm (nGO) can affect cell behaviour and especially their need for the key amino acid L-glutamine (L-Glu). RESULTS: Chicken embryo muscle cells and their precursors, cultured in vitro, were used as the experimental model. The mesenchymal stem cell, collected from the hind limb of the chicken embryo at day 8 were divided into 4 groups; the control group and groups treated with nGO, L-Glu and nGO supplied with L-Glu (nGOxL-Glu). The roughness of the surface of the plastic plate covered with nGO was much lower than a standard plate. The test of nGO biocompatibility demonstrated that the cells were willing to settle on the nGO without any toxic effects. Moreover, nGO by increasing hydrophilicity and reducing roughness and presumably through chemical bonds available on the GO surface stimulated the colonisation of primary stromal cells that promote embryonic satellite cells. The viability significantly increased in cells cultured on nGOxL-Glu. Observations of cell morphology showed that the most mature state of myogenesis was characteristic for the group nGOxL-Glu. This result was confirmed by increasing the expression of MYF5 genes at mRNA and protein levels. nGO also increased the expression of MYF5 and also very strongly the expression of PAX7 at mRNA and protein levels. However, when analysing the expression of PAX7, a positive link was observed between the nGO surface and the addition of L-Glu. CONCLUSIONS: The use of nGO and L-Glu supplement may improve myogenesis and also the myogenic potential of myocytes and their precursors by promoting the formation of satellite cells. Studies have, for the first time, demonstrated positive cooperation between surface properties nGO and L-Glu supplementation to the culture medium regarding the myogenic potential of cells involved in muscle formation.

Silver and Graphenic Carbon Nanostructures Differentially Influence the Morphology and Viability of Cardiac Progenitor Cells.

The characteristic features of nanomaterials provide rich opportunities for a broad range of applications due to their different physicochemical properties. Nanocolloidal silver and graphenic carbon materials differ in most physicochemical characteristics, except for their nanodimensions. Since there is a growing demand for stem cell therapies for coronary disorders, examining cardiac progenitor cells (CPC) in terms of their response to nanostructure treatment seems to be a reasonable approach. Morphological studies and viability assessments were performed with CPC in vitro, treated with small concentrations of silver nanoparticles (AgNP), hierarchical nanoporous graphenic carbon (HNC) and their mixtures. A viability test confirmed the morphological assessment of CPC treated with AgNP and HNC; moreover, the action of both nanomaterials was time-dependent and dose-dependent. For AgNP, between the two of the applied concentrations lies a border between their potential beneficial effect and toxicity. For HNC, at a lower concentration, strong stimulation of cell viability was noted, whereas a higher dosage activated their differentiation. It is necessary to perform further research examining the mechanisms of the action of AgNP and especially of unexplored HNC, and their mixtures, on CPC and other cells.

Diamond Nanoparticles Downregulate Expression of CycD and CycE in Glioma Cells.

Our previous studies have shown that diamond nanoparticles (NDs) exhibited antiangiogenic and proapoptotic properties in vitro in glioblastoma multiforme (GBM) cells and in tumors in vivo. Moreover, NDs inhibited adhesion, leading to the suppression of migration and invasion of GBM. In the present study, we hypothesized that the NDs might also inhibit proliferation and cell cycle in glioma cells. Experiments were performed in vitro with the U87 and U118 lines of GBM cells, and for comparison, the Hs5 line of stromal cells (normal cells) after 24 h and 72 h of treatment. The analyses included cell morphology, cell death, viability, and cell cycle analysis, double timing assay, and gene expression (Rb, E2F1, CycA, CycB, CycD, CycE, PTEN, Ki-67). After 72 h of ND treatment, the expression level of Rb, CycD, and CycE in the U118 cells, and E2F1, CycD, and CycE in the U87 cells were significantly lower in comparison to those in the control group. We observed that decreased expression of cyclins inhibited the G1/S phase transition, arresting the cell cycle in the G0/G1 phase in glioma cells. The NDs did not affect the cell cycle as well as PTEN and Ki-67 expression in normal cells (Hs5), although it can be assumed that the NDs reduced proliferation and altered the cell cycle in fast dividing cells.

Investigation of platinum nanoparticle properties against U87 glioblastoma multiforme.

INTRODUCTION: Gliomas are the most aggressive and common primary tumors of the central nervous system (CNS). Many side effects of drugs containing platinum and their poor penetration of the CNS are major drawbacks in glioma therapy. The aim of the study was to investigate and compare the toxicity of platinum nanoparticles and cisplatin and their anticancer properties in examination with a U87 glioma cell line and tumor. MATERIAL AND METHODS: Nanoparticles of platinum (NP-Pt) and cisplatin were incubated with U87 glioma cells or injected directly into tumor tissue. The biological properties of NP-Pt and cisplatin were compared through the morphology, viability, mortality, genotoxicity and the type of cell death of U87 glioma cells, the morphology and ultrastructure of glioma tumor, and expression of caspase-3, p53 and PCNA mRNA. RESULTS: NP-Pt at concentrations of 0.14 µM/ml, 0.29 µM/ml and 0.65 µM/ml had a harmful influence on viability of U87 glioblastoma multiforme (GBM) cells, but also showed genotoxic properties as well as a pro-apoptotic effect on cancer cells. It was found that NP-Pt decreased the weight and volume of U87 GBM tumor tissue and caused pathomorphological changes in the ultrastructure and morphology of tumor tissue, but they also upregulated p53 and caspase-3 mRNA expression. CONCLUSIONS: The comparison between the effectiveness of glioblastoma treatment by NP-Pt vs cisplatin showed promising results for future studies. The results indicate that the properties of NP-Pt might be utilized for brain cancer therapy.

Toxicity studies of six types of carbon nanoparticles in a chicken-embryo model.

In the present study, the toxicity of six different types of carbon nanoparticles (CNPs) was investigated using a chicken-embryo model. Fertilized chicken eggs were divided into the following treatment groups: placebo, diamond NPs, graphite NPs, pristine graphene, small graphene oxide, large graphene oxide, and reduced graphene oxide. Experimental solutions at a concentration of 500 µg/mL were administrated into the egg albumin. Gross pathology and the rate of survival were examined after 5, 10, 15, and 20 days of incubation. After 20 days of incubation, blood samples were collected and the weight of the body and organs measured. The relative ratio of embryo survival decreased after treatment all treatments except diamond NPs. There was no correlation between the rate of survival and the ζ-potential or the surface charge of the CNPs in solution. Body and organ weight, red blood-cell morphology, blood serum biochemical parameters, and oxidative damage in the liver did not differ among the groups. These results indicate that CNPs can remain in blood circulation without any major side effects, suggesting their potential applicability as vehicles for drug delivery or active compounds per se. However, there is a need for further investigation of their properties, which vary depending on production methods and surface functionalization.

Diamond Nanoparticles Modify Curcumin Activity: In Vitro Studies on Cancer and Normal Cells and In Ovo Studies on Chicken Embryo Model.

Curcumin has been studied broadly for its wide range of biological activities, including anticancer properties. The major problem with curcumin is its poor bioavailability, which can be improved by the addition of carriers, such as diamond nanoparticles (DN). They are carbon allotropes, and are therefore biocompatible and easily taken up by cells. DN are non-toxic and have antiangiogenic properties with potential applications in cancer therapy. Their large surface makes them promising compounds in a drug delivery system for bioactive agents, as DN create bio-complexes in a fast and simple process of self-organisation. We investigated the cytotoxicity of such bio-complexes against liver cancer cells and normal fibroblasts, revealing that conjugation of curcumin with DN significantly improves its activity. The experiment performed in a chicken embryo model demonstrated that neither curcumin nor DN nor bio-complexes affect embryo development, even though DN can form deposits in tissues. Preliminary results confirmed the applicability of DN as an efficient carrier of curcumin, which improves its performance against cancer cells in vitro, yet is not toxic to an organism, which makes the bio-complex a promising anticancer agent.

Toxicity of different forms of graphene in a chicken embryo model.

In the present work, the toxicity of three forms of graphene: pristine graphene (pG), graphene oxide (GO), and reduced graphene oxide (rGO) was investigated using a chicken embryo model. Fertilized chicken eggs were divided into the control group and groups administered with pG, GO, and rGO, in concentrations of 50, 500, and 5000 µg/ml. The experimental solutions were injected in ovo into the eggs, and at day 18 of incubation, the embryo survival, body and organ weights, the ultrastructure of liver samples, and the concentration of 8-hydroxy-2'-deoxyguanosine (8-OHdG) in the livers were measured. Survival of embryos decreased significantly after treatment with all types of graphene, but not in a dose-dependent manner. The body weights were only slightly affected by the highest doses of graphene, while the organ weights were not different among treatment groups. In all experimental groups, atypical hepatocyte ultrastructure and mitochondrial damage were observed. The concentration of the marker of DNA damage 8-OHdG in the liver significantly decreased after pG and rGO treatments. Further in vivo studies with different animal models are necessary to clarify the level of toxicity of different types of graphene and to estimate the concentrations appropriate to evaluate their biomedical applications and environmental hazard.

Long Term Influence of Carbon Nanoparticles on Health and Liver Status in Rats.

Due to their excellent biocompatibility, carbon nanoparticles have been widely investigated for prospective biomedical applications. However, their impact on an organism with prolonged exposure is still not well understood. Here, we performed an experiment investigating diamond, graphene oxide and graphite nanoparticles, which were repeatedly administrated intraperitoneally into Wistar rats for four weeks. Some of the animals was sacrificed after the last injection, whereas the rest were sacrificed twelve weeks after the last exposure. We evaluated blood morphology and biochemistry, as well as the redox and inflammatory state of the liver. The results show the retention of nanoparticles within the peritoneal cavity in the form of prominent aggregates in proximity to the injection site, as well as the presence of some nanoparticles in the mesentery. Small aggregates were also visible in the liver serosa, suggesting possible transportation to the liver. However, none of the tested nanoparticles affected the health of animals. This lack of toxic effect may suggest the potential applicability of nanoparticles as drug carriers for local therapies, ensuring accumulation and slow release of drugs into a targeted tissue without harmful systemic side effects.

Graphene Functionalized with Arginine Decreases the Development of Glioblastoma Multiforme Tumor in a Gene-Dependent Manner.

Our previous studies revealed that graphene had anticancer properties in experiments in vitro with glioblastoma multiforme (GBM) cells and in tumors cultured in vivo. We hypothesized that the addition of arginine or proline to graphene solutions might counteract graphene agglomeration and increase the activity of graphene. Experiments were performed in vitro with GBM U87 cells and in vivo with GBM tumors cultured on chicken embryo chorioallantoic membranes. The measurements included cell morphology, mortality, viability, tumor morphology, histology, and gene expression. The cells and tumors were treated with reduced graphene oxide (rGO) and rGO functionalized with arginine (rGO + Arg) or proline (rGO + Pro). The results confirmed the anticancer effect of graphene on GBM cells and tumor tissue. After functionalization with amino acids, nanoparticles were distributed more specifically, and the flakes of graphene were less agglomerated. The molecule of rGO + Arg did not increase the expression of TP53 in comparison to rGO, but did not increase the expression of MDM2 or the MDM2/TP53 ratio in the tumor, suggesting that arginine may block MDM2 expression. The expression of NQO1, known to be a strong protector of p53 protein in tumor tissue, was greatly increased. The results indicate that the complex of rGO + Arg has potential in GBM therapy.

In Ovo Administration of Silver Nanoparticles and/or Amino Acids Influence Metabolism and Immune Gene Expression in Chicken Embryos.

Due to their physicochemical and biological properties, silver nanoparticles (NanoAg) have a wide range of applications. In the present study, their roles as a carrier of nutrients and an immunomodulator were tested in chicken embryos. Cysteine (Cys)+NanoAg injected embryos had smaller livers but heavier breasts on the 19th day of embryogenesis. Cys injected embryos had lower oxygen consumption compared to threonine (Thr) or NanoAg injected embryos. The energy expenditure in Thr+NanoAg, or NanoAg injected embryos was higher than Cys or Cys+NanoAg but was not different from uninjected control embryos. Relative expression of the hepatic insulin-like growth factor-I (IGF-I) gene was higher in Cys or NanoAg injected embryos after lipopolysaccharide (LPS) induction. The gene expression of hepatic tumour necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) did not differ among amino acids, NanoAg and uninjected controls in the non-LPS groups, but increased by many folds in the LPS treated NanoAg, Cys and Cys+NanoAg groups. In LPS treated spleens, TNF-α expression was also up-regulated by NanoAg, amino acids and their combinations, but interleukin-10 (IL-10) expression was down-regulated in Thr, Cys or Thr+NanoAg injected embryos. Toll like receptor-2 (TLR2) expression did not differ in NanoAg or amino acids injected embryos; however, toll like receptor-4 (TLR4) expression was higher in all treated embryos, except for Cys+NanoAg, than in uninjected control embryos. We concluded that NanoAg either alone or in combination with amino acids did not affect embryonic growth but improved immunocompetence, indicating that NanoAg and amino acid complexes can act as potential agents for the enhancement of innate and adaptive immunity in chicken.

Interaction of graphene family materials with Listeria monocytogenes and Salmonella enterica.

Graphene family materials have unique properties, which make them valuable for a range of applications. The antibacterial properties of graphene have been reported; however, findings have been contradictory. This study reports on the antimicrobial proprieties of three different graphene materials (pristine graphene (pG), graphene oxide (GO), and reduced graphene oxide (rGO)) against the food-borne bacterial pathogens Listeria monocytogenes and Salmonella enterica. A high concentration (250 µg/mL) of all the analyzed graphenes completely inhibited the growth of both pathogens, despite their difference in bacterial cell wall structure. At a lower concentration (25 µg/mL), similar effects were only observed with GO, as growth inhibition decreased with pG and rGO at the lower concentration. Interaction of the nanoparticles with the pathogenic bacteria was found to differ depending on the form of graphene. Microscopic imaging demonstrated that bacteria were arranged at the edges of pG and rGO, while with GO, they adhered to the nanoparticle surface. GO was found to have the highest antibacterial activity.

Effect of silver nanoparticles and hydroxyproline, administered in ovo, on the development of blood vessels and cartilage collagen structure in chicken embryos.

It has been considered that concentrations of certain amino acids in the egg are not sufficient to fully support embryonic development of modern broilers. In this study we evaluated embryo growth and development with particular emphasis on one of the major components of connective tissue, collagen. Experiments were performed on Ross 308 chicken embryos from 160 fertilised eggs. Experimental solutions of silver nanoparticles (Ag), hydroxyproline solution (Hyp) and a complex of silver nanoparticles with hydroxyproline (AgHyp) were injected into albumen, and embryos were incubated until day 20. An assessment of the mass of embryo and selected organs was carried out followed by measurements of the expression of the key signalling factors' fibroblast growth factor-2 (FGF-2) and vascular endothelial growth factor-A (VEGF-A). Finally, an evaluation of collagen microstructure using scanning electron microscopy was performed. Our results clearly indicate that Hyp, Ag and AgHyp administered in ovo to chicken embryos did not harm embryos. Comparing to the control group, Hyp, Ag and the AgHyp complex significantly upregulated expression of the FGF-2 at the mRNA and protein levels. Moreover, Hyp, Ag and, in particular, the complex of AgHyp significantly increased blood vessel size, cartilage collagen fibre lattice size and bundle thickness. The general conclusion from this study is that AgHyp treatment may help to build a stronger and longer lasting form of collagen fibres.

Toxicity of pristine graphene in experiments in a chicken embryo model.

Evaluation of the potential cytotoxicity of graphene is a key factor for medical applications, where flakes or a surface of graphene may be used as bioactive molecules, drug carriers, or biosensors. In the present work, effects of pristine graphene (pG) on the development of a living organism, with an emphasis on morphological and molecular states of the brain, were investigated using a chicken embryo model. Fertilized chicken eggs were divided into the control group and groups administered with pG suspended in milli-Q water at concentrations of 50 µg/L, 100 µg/L, 500 µg/L, 1,000 µg/L, 5,000 µg/L, and 10,000 µg/L (n=30 per group). The experimental solutions were injected in ovo into the albumin and then the eggs were incubated. After 19 days of incubation, the survival, weight of the body and organs, and blood serum biochemical indices were measured. The brain samples were collected for microscopic examination of brain ultrastructure and measurements of gene and protein expression. Survival of embryos was significantly decreased after treatment with pG, but the body and organ weights as well as biochemical indices were not affected. In all treatment groups, some atypical ultrastructures of the brain were observed, but they were not enhanced by the increasing concentrations of pG. Expression of proliferating cell nuclear antigen at the messenger ribonucleic acid level was downregulated, and the number of proliferating cell nuclear antigen-positive nuclei was significantly reduced in the 500-10,000 µg/L groups compared with the control group, indicating a decreased rate of deoxyribonucleic acid synthesis in the brain. The present results demonstrate some harmful effects of the applied pG flakes on the developing organism, including brain tissue, which ought to be considered prior to any medical applications.

Nano-nutrition of chicken embryos. The effect of in ovo administration of diamond nanoparticles and L-glutamine on molecular responses in chicken embryo pectoral muscles.

It has been demonstrated that the content of certain amino acids in eggs is not sufficient to fully support embryonic development. One possibility to supply the embryo with extra nutrients and energy is in ovo administration of nutrients. Nanoparticles of diamond are highly biocompatible non-toxic carbonic structures, and we hypothesized that bio-complexes of diamond nanoparticles with L-glutamine may affect molecular responses in breast muscle. The objective of the investigation was to evaluate the effect of diamond nanoparticle (ND) and L-glutamine (Gln) on expression of growth and differentiation factors of chicken embryo pectoral muscles. ND, Gln, and Gln/ND solutions (50 mg/L) were injected into fertilized broiler chicken eggs at the beginning of embryogenesis. Muscle tissue was dissected at day 20 of incubation and analysed for gene expression of FGF2, VEGF-A, and MyoD1. ND and especially Gln/ND up-regulated expression of genes related to muscle cell proliferation (FGF2) and differentiation (MyoD1). Furthermore, the ratio between FGF2 and MyoD1 was highest in the Gln/ND group. At the end of embryogenesis, Gln/ND enhanced both proliferation and differentiation of pectoral muscle cells and differentiation dominated over proliferation. These preliminary results suggest that the bio-complex of glutamine and diamond nanoparticles may accelerate growth and maturation of muscle cells.

Carbon nanoparticles downregulate expression of basic fibroblast growth factor in the heart during embryogenesis.

Carbon nanoparticles, with their high biocompatibility and low toxicity, have recently been considered for biomedical applications, including antiangiogenic therapy. Critical to normal development and tumor formation, angiogenesis is the process of forming capillary blood vessels from preexisting vessels. In the present study, we evaluated the effects of diamond and graphite nanoparticles on the development of chicken embryos, as well as vascularization of the chorioallantoic membrane and heart at the morphological and molecular level. Nanoparticles did not affect either body/heart weight or serum indices of the embryos' health. However, vascularization of the heart and the density of branched vessels were significantly reduced after treatment with diamond nanoparticles and, to a lesser extent, graphite nanoparticles. Application of nanoparticles significantly downregulated gene and protein expression of the proangiogenic basic fibroblast growth factor, indicating that both diamond and graphite nanoparticles inhibit angiogenesis.

Nano-nutrition of chicken embryos. The effect of silver nanoparticles and ATP on expression of chosen genes involved in myogenesis.

It has been suggested that the quantity and quality of nutrients stored in the egg might not be optimal for the fast rate of chicken embryo development in modern broilers, and embryos could be supplemented with nutrients by in ovo injection. Recent experiments showed that in ovo feeding reduces post-hatch mortality and skeletal disorders and increases muscle growth and breast meat yield. Adenosine triphosphate (ATP) is a "ready for use" energetic molecule, while nanoparticles of silver (Nano-Ag) may penetrate tissues as well as cells and localise inside cells. In this investigation, we hypothesised that silver nanoparticles could be used as a protective carrier for ATP as well as an active agent. ATP and/or an ATP complex with Nano-Ag would be delivered to the muscle cells as a gene expression regulator and promoter of growth and development of embryo breast muscle. A collection of 160 broiler eggs was randomly divided into a Control group without injection and injected groups with hydrocolloids of Nano-Ag, ATP or a complex of Nano-Ag and ATP (Nano-Ag/ATP). The embryos were evaluated on day 20 of incubation. The results indicate that the application of ATP to chicken embryos increases expression of fibroblast growth factor 2 (FGF2), vascular endothelial growth factor (VEGF) and Na(+)/K(+) transporting ATPase (ATP1A1), which may indicate that an extra energy source can enhance molecular mechanisms of muscle cell proliferation. Nano-Ag also up-regulated expression of FGF2, VEGF, ATP1A1 and, also up-regulated expression of myogenic differentiation 1(MyoD1), affecting cell differentiation. The results indicate that ATP and Nano-Ag may accelerate growth and maturation of muscle cells.

Effect of silver nanoparticles on growth performance, metabolism and microbial profile of broiler chickens.

This study evaluated the potential of silver nanoparticles (AgNano) as an antimicrobial growth-promoting supplement for broiler chickens. One hundred forty-four seven-day-old broiler chicks were distributed randomly to AgNano treatments at 0, 10 and 20 mg/kg (Control, Group AgNano10, and Group AgNano20, respectively) provided via the drinking water from day 7 to 36 post-hatching. Body weight and feed consumption were measured weekly. In addition, balance and respiration experiments were carried out to determine nitrogen (N) utilisation and energy retention. At days 22 and 36, blood samples and intestinal content were collected to evaluate the effects of AgNano on plasma concentration of immunoglobulins and the intestinal microflora, respectively. The provision of water solutions containing different concentrations of AgNano had no effect on postnatal growth performance and the energy metabolism of broiler chickens. However, in Group AgNano10 N intake (p = 0.05) and retention (p = 0.03) was increased, but N excretion and efficiency of utilisation was not affected. The populations of bacteria in the intestinal samples were not affected by AgNano supplementation. The concentration of immunoglobulin (IgG) in the blood plasma of broilers supplemented with AgNano decreased at day 36 (p = 0.012). The results demonstrated that AgNano affects N utilisation and plasma IgG concentration; however, it does not influence the microbial populations in the digestive tract, the energy metabolism and growth performance of chickens.

Silver nanoparticles administered to chicken affect VEGFA and FGF2 gene expression in breast muscle and heart.

Nanoparticles of colloidal silver (AgNano) can influence gene expression. Concerning trials of AgNano application in poultry nutrition, it is useful to reveal whether they affect the expression of genes crucial for bird development. AgNano were administered to broiler chickens as a water solution in two concentrations (10 and 20 ppm). After dissection of the birds, breast muscles and hearts were collected. Gene expression of FGF2 and VEGFA on the mRNA and protein levels were evaluated using quantitative polymerase chain reaction and enzyme-linked immunosorbent assay methods. The results for gene expression in the breast muscle revealed changes on the mRNA level (FGF2 was up-regulated, P < 0.05) but not on the protein level. In the heart, 20 ppm of silver nanoparticles in drinking water increased the expression of VEGFA (P < 0.05), at the same time decreasing FGF2 expression both on the transcriptional and translational levels. Changes in the expression of these genes may lead to histological changes, but this needs to be proven using histological and immunohistochemical examination of tissues. In general, we showed that AgNano application in poultry feeding influences the expression of FGF2 and VEGFA genes on the mRNA and protein levels in growing chicken.