Investigation On The Biosafety Of Prussian Blue Nanoparticles In Mice

Prussian blue nanoparticles(PB NPs)have attracted much attention in biomedical field due to their unique physical and chemical properties,and have made a series of research progress in cancer diagnosis and treatment.The biosafety of nanoparticles is a key issue in their clinical transformation.At present,related researches on PB NPs were mainly limited in acute toxicity and short-term biodistribution.In this dissertation,we evaluated the biosafety of PB NPs,including toxicology,pharmacokinetics,proteomics and metabolomics after intravenous injection to mice.1.The acute and subacute toxicities of PB NPs at different doses(low 5 mg/kg,medium 10 mg/kg and high 20 mg/kg)in mice were evaluated via the intravenous injection.All mice were alive within 30 days after injection.The physiological and biochemical indexes were in normal range,and no abnormalities were observed in histopathological sections.There was no obvious toxicity showed in low and medium dose groups.However,in high dose group,the mice showed symptoms including spiritlessness,shortness of breath,slowness of movement within several minutes after injection,and their body weights decreased in the first two days after injection,then returned to normal.The enrichment of PB NPs was observed in the lung and liver sections in high dose group on the 1st day after injection.It was suggested acute toxicity in high dose group(20 mg/kg).2.The stability of PB NPs in simulated body fluid was studied in vitro,it was found that PB NPs could degrade slowly in simulated body fluid.The pharmacokinetics of high dose PB NPs(20 mg/kg)in mice was studied.The results showed that the residence time of PB NPs in blood was short.PB NPs were removed from blood within 4 h after injection,and then mainly distributed in the liver and lung,but gradually cleared from the tissues.Through the identification of components of PB NPs plasma protein corana,it was found that there were a large number of opsonin in PB NPs protein corana.It was speculated that opsonization mediated by opsonin was the key factor leading to the accumulation of PB NPs in liver and lung.3.Proteomics and metabolomics were used to analyze the lung of mice after high dose of PB NPs(20 mg/kg)was injected via tail vein.The sampling time was the 7th and 60th day after injection,respectively.The results showed that adrenergic signaling pathway,linoleic acid and aromatic amino acid metabolism pathways in lung were affected at 7th and 60th day after injection.The level of inflammatory factor prostaglandin E2(PGE2)in lung increased at the 7th day after injection.The expression of inflammatory factors calbindin(S100A8/9),lipocalin 2(LCN2)and matrix metalloproteinase(MMP9)were upregulated in the lung at the 60th day after injection,and there was a phenomenon of leukocyte transepithelial migration pathway,indicating there was inflammatory reaction in the tissue.The upregulation of NOX,hexokinase(HK)and transferrin(TF),the increase of GSH level and the enrichment of GSH metabolism indicated that there was oxidative stress in the cells.4.Proteomics and metabolomics were used to analyze the liver of mice after high dose of PB NPs(20 mg/kg)was injected via tail vein.The sampling time was 7th and 60th day after injection,respectively.The results showed that the expressions of lactic dehydrogenase(LDH)and cytochrome P450(CYP2A5)in liver were upregulated at the 7th day after injection.The expression of S100A8/9 was upregulated in the liver at the 60th day after injection,which indicated that there was inflammatory reaction and intracellular oxidative stress.At the 7th and 60th day after injection,some metabolic pathways in the liver,such as purine metabolism,pantothenic acid and CoA synthesis,biotin metabolism,phenylalanine metabolism and so on,were affected,which not only indicated the occurrence of inflammatory response and oxidative stress,but also indicated the activation of anti-inflammatory and anti-oxidative responses.The above results indicated that high dose of PB NPs does not cause obvious toxic reaction after intravenous injection,but it could be identified and captured by phagocytes,then distributed in the liver and lung of mice.PB NPs could cause mild inflammatory reaction and oxidative stress in tissues during the process of degradation and clearance of PB NPs in liver and lung.The results further confirmed the toxicological characteristics of PB NPs after intravenous injection.