Intact NPs Research Articles

Proteome analysis of egg yolk after exposure to zinc oxide nanoparticles

Zinc oxide nanoparticles (ZnO NPs) are promising candidates as animal diet additive. However, several studies have reported that ZnO NPs cause adverse effects on organisms. Hen egg yolk proteins play vital roles during embryonic development. Although we found ZnO NPs altered the function of the ovary and liver, the effects of ZnO NPs on egg yolk proteins are not as yet understood. In this report, egg yolk proteome was investigated after ZnO NPs treatment. A total of 37 proteins were specifically regulated just by ZnO-NP-50 mg/kg, and 22 proteins were changed solely by ZnSO4-50 mg/kg. Seventeen proteins were regulated by both ZnO-NP-50 mg/kg and ZnSO4-50 mg/kg treatments. Furthermore, the proteins changed by ZnO NPs or ZnSO4 were enriched into different functional groups, respectively, by GO analysis and KEGG pathway enrichment. For the first time, this investigation reports that intact NPs produce a different impact on the egg yolk proteome compared to that of Zn2+. The changes in protein levels by ZnO NPs in egg yolk might influence the value of egg yolk as nutrient and the embryonic development.

Regulation of neuroendocrine cells and neuron factors in the ovary by zinc oxide nanoparticles.

The pubertal period is an important window during the development of the female reproductive system. Development of the pubertal ovary, which supplies the oocytes intended for fertilization, requires growth factors, hormones, and neuronal factors. It has been reported that zinc oxide nanoparticles (ZnO NPs) cause cytotoxicity of neuron cells. However, there have been no reports of the effects of ZnO NPs on neuronal factors and neuroendocrine cells in the ovary (in vivo). For the first time, this in vivo study investigated the effects of ZnO NPs on gene and protein expression of neuronal factors and the population of neuroendocrine cells in ovaries. Intact NPs were detected in ovarian tissue and although ZnO NPs did not alter body weight, they reduced the ovary organ index. Compared to the control or ZnSO4 treatments, ZnO NPs treatments differentially regulated neuronal factor protein and gene expression, and the population of neuroendocrine cells. ZnO NPs changed the contents of essential elements in the ovary; however, they did not alter levels of the steroid hormones estrogen and progesterone. These data together suggest that intact ZnO NPs might pose a toxic effect on neuron development in the ovary and eventually negatively affect ovarian developmental at puberty.

Differential Regulation of Gene and Protein Expression by Zinc Oxide Nanoparticles in Hen's Ovarian Granulosa Cells: Specific Roles of Nanoparticles.

Annually, tons and tons of zinc oxide nanoparticles (ZnO NPs) are produced in the world. And they are applied in almost all aspects of our life. Their release from the products into environment may pose issue for human health. Although many studies have reported the adverse effects of ZnO NPs on organisms, little is known about the effects on female reproductive systems or the related mechanisms. Quantitative proteomics have not been applied although quantitative transcriptomics have been used in zinc oxide nanoparticles (ZnO NPs) research. Genes are very important players however proteins are the real actors in the biological systems. By using hen’s ovarian granulosa cells, it was found that ZnO-NP-5μg/ml and ZnSO4-10μg/ml treatments produced the same amount of intracellular Zn and resulted in similar cell growth inhibition. And NPs were found in the treated cells. However, ZnO-NP-5μg/ml specifically regulated the expression of genes and proteins compared with that in ZnSO4-10μg/ml treatment. For the first time, this investigation reports that intact NPs produce different impacts on the expression of genes and proteins involved in specific pathways compared to that by Zn2+. The findings enrich our knowledge for the molecular insights of zinc oxide nanoparticles effects on the female reproductive systems. This also may raise the health concern that ZnO NPs may adversely affect the female reproductive systems through regulation of specific signaling pathways.

Bioaccumulation of ZnO-NPs in Earthworm Eisenia fetida (Savigny)

Zinc oxide nanoparticles (ZnO-NPs) are increasingly used in nano fertilizers, sunscreens, biosensors, food additives, pigments, rubber manufacture and electronic materials. With wide application of ZnO-NPs, concern has been raised about its unintentional health hazards and environmental impacts. In the present study, we tested toxicity and uptake of ZnO-NPs as a marker of potential ecological harm. We provided multiple lines of evidence including, percentage of mortality, DNA damage, superoxide dismutase, lignin peroxidase, cellulolytic activity and transmission electron microscopy of coelomic fluid and earthworm tissue to express bioavailability and bioaccumulation of ZnONPs from soil to earthworm. The aggregates of NPs were observed in coelomic fluid and their tissues, away from portal of their entry. The results from response of antioxidant system combined with DNA damage indicated that ZnO-NPs could not induce significant damage to earthworms. The study demonstrated bioavailability of ZnO-NPs was very high throughout the earthworm cross sections in all exposures of NPs particularly at exposure of 10nm sized ZnO-NPs and revealed that intact NPs can be taken up by earthworm from soil and having good potential of bioremediation into non- toxic forms.

Mechanisms of chitosan-coated poly(lactic-co-glycolic acid) nanoparticles for improving oral absorption of 7-ethyl-10-hydroxycamptothecin

Chitosan-modified poly(lactic-co-glycolic acid) nanoparticles (CHI/PLGA NPs) loaded with 7-ethyl-10-hydroxycamptothecin (SN-38), named CHI/PLGA/SN-38 NPs, were successfully prepared using an oil-in-water (O/W) solvent evaporation method. The physicochemical properties of the novel NPs were characterized by DLS, Zeta potential, SEM, DSC, XRD, and FTIR. The encapsulation efficiency and drug loading content were 71.83 (±2.77)% and 6.79 (±0.26)%, respectively. In vitro drug release in the simulated gastric juice was lower than that in the intestinal juice. In situ single-pass intestinal perfusion (SPIP) studies indicated a dramatic improvement of drug absorption as a result of the synergistic effect between CHI and PLGA on P-glycoprotein (Pgp) inhibition. CHI/PLGA NPs showed high cellular uptake and low efflux for drugs in Caco-2 cells. The cytotoxicity studies revealed that CHI/PLGA NPs had a transient effect on the membrane integrity, but did not have an influence on cell viability. Based on the in vitro release studies, SPIP, and intracellular drug accumulation and transport investigations, we speculate rationally that CHI/PLGA NPs were mainly internalized in the form of intact NPs, thus escaping the recognition of enterocyte Pgp and avoiding efflux into the apical part of the enterocytes. After partial release of drugs inside the enterocytes, CHI/PLGA interfered with the microenvironment of Pgp and further weakened the Pgp-mediated efflux. Then, the drug-loaded NPs exited via the exocytose effect from the basal part of the enterocytes and entered the blood circulation. These results showed that CHI/PLGA NPs would be smart oral delivery carriers for antineoplastic agents that are also Pgp substrates.

Probing metabolic stability of CdSe nanoparticles: Alkaline extraction of free cadmium from liver and kidney samples of rats exposed to CdSe nanoparticles

Cadmium selenide nanoparticles (CdSe NPs) exhibit novel optoelectronic properties for potential biomedical applications. However, their metabolic stability is not fully understood because of the difficulties in measurement of free Cd from biological tissues of exposed individuals. In this study, alkaline dissolution with tetramethylammonium hydroxide (TMAH) is demonstrated for selective determination of free Cd and intact NPs from liver and kidney samples of animals that were exposed to thiol-capped CdSe NPs. Aqueous suspensions of CdSe NPs (3.2 nm) were used to optimize the conditions for extracting free Cd without affecting NPs. Nanoparticles were found to aggregate when heated in TMAH without releasing any significant Cd to solution. Performance of the method in discriminating free Cd and intact NPs were verified by Dogfish Liver (DOLT-4) certified reference material. The samples from the animals were digested in 4 mL TMAH at 70 °C to extract free Cd followed by analysis of aqueous phase by ICP-MS. Both liver and kidney contained significant levels of free Cd. Total Cd was higher in the liver, while kidney accumulated mostly free Cd such that up to 47.9% of total Cd in the kidney was free Cd when NPs were exposed to UV-light before injection.