| Objectives La2O3 nanoparticles(La2O3 NPs)as the research object,and the traditional toxicological methods were used.The traditional toxicological methods were used to study the toxicity of La2O3 NPs to liver and kidney in vitro and in vivo,and reveal the effects of NPs on body weight,organ coefficient,clinical biochemical indexes,oxidative stress level,liver and kidney histopathology and cell ultrastructure.In addition,reveal the transcription and translation levels on the expression of Nrf-2/ARE pathway related genes in liver and kidney cells in vivo and in vitro.Thus provide theoretical basis for the toxicity monitoring and intervention of La2O3 NPs.Methods 1 The structure and morphology of La2O3 NPs were observed by X-ray diffraction(XRD),scanning electron microscope(SEM)and transmission electron microscope(TEM),and the particle size distributions of La2O3 NPs were detected by nano particle size analyzer.The toxicity of La2O3 NPs in Kunming mice was evaluated by intragastric administration of 0,250,500 and 1000 mg/kg BW for 14 days.The distribution of lanthanum in the main organs of mice was analyzed by inductively coupled ion mass spectrometry(ICP-MS).2 The toxicity of La2O3 NPs(0,2.5,5 and 10 mg/kg BW,named Con,NL,NM and NH)in Kunming mice was evaluated by intragastric administration for 90 days.The blood of mice was collected,and the liver functions in mice serum were detected by automatic biochemical analyzer.The pathological changes of liver were observed by HE staining,and the ultrastructure of liver cells was observed by TEM.The GSH contents,MDA levels and SOD activities in mice liver were detected by commertial biochemical kits.The inflammation and apoptosis of liver cells were detected by immunohistochemistry and TUNEL staining.q RT-PCR and western blotting were used to detect the expressions of Nrf-2 signaling pathway,bile acid metabolism pathway,inflammation and apoptosis related genes,and the transcription and translation levels of Nrf-2 signaling pathway,inflammation and apoptosis related genes in kidney.3 Hep G2 and HK-2 cells were used as the in vitro toxicity model of La2O3 NPs(dose: 1,10 and 100?g/m L).CCK-8 kit was used to determine the survival rate,biochemical kit was used to detect ROS contents,MDA levels and SOD activities,LDH kit was used to detect the integrity of cell membrane,and flow cytometry was used to detect the apoptosis rate of the cells.q RT-PCR and western blotting were used to detect the transcription and translation of Nrf-2 pathway related genes in Hep G2 and HK-2 cells.Results 1 XRD results showed that La2O3 NPs had high purity.SEM analysis results showed that La2O3 NPs were polymer composed of many connected nanosheets.The results of SEM and TEM indicate that La2O3 NPs were composed of many nano flakes.After the exposure of La2O3 NPs for 14 days,it was found that the order of La accumulation in various organs was liver>kidney>spleen>testis>brain>heart.2 The results showed that high dose of La2O3 NPs could induce obvious hepatotoxicity in mice.The concentrations of ALT,AST,TBA and TBIL in NH group were significantly increased(P<0.05).The pathology and ultrastructure of liver cells in NH group were changed.Compared with the control group,GSH contents and MDA levels in liver tissue in NH group were significantly increased(P<0.05).Immunohistochemical of NF-?B,BAX and TUNEL staining showed that the number of inflammatory and apoptotic cells in mice liver were increased in a dose-dependent manner.The m RNA and protein expression levels of Nrf-2,HO-1,NQO1,Gclc,Gclm,Fxr,Cyp7a1,Bsep,Mrp2 and Bcl-2 were significantly decreased in NH group(P<0.05),while the m RNA and protein expression levels of Mrp3,TNF-?,COX-2,IL-1?,NF-?B,BAX and Caspase-3 were significantly increased(P<0.05).In vitro study found that the cell viability of Hep G2 cells decreased significantly at the concentration of 100 ?g/m L(P<0.05).After Hep G2 cells were treated with different doses of La2O3 NPs,the ROS contents,MDA levels,LDH leakage rates increased significantly,while SOD activities decreased significantly in 100 ?g/m L group(P<0.05).Compared with the control group,the apoptosis rate of 100 ?g/m L group increased significantly(P<0.05).The m RNA and protein expression levels of Nrf-2,HO-1,NQO1,?-GCS,Cytochrome C and BAX in 100 ?g/m L group were significantly increased,while the expression levels of Bcl-2 were significantly decreased(P<0.05).3 The nephrotoxicity induced by La2O3 NPs showed that the levels of BUN,Cr and UA were significantly increased(P<0.05).The pathology and ultrastructure of kidney cells in NH group were changed.Compared with the control group,MDA levels were significantly increased,and SOD activities were significantly decreased in NH group(P<0.05).Immunohistochemical stainings of NF-?B,BAX and TUNEL staning showed that the number of inflammatory and apoptotic cells in NM and NH groups were significantly increased(P<0.05).The m RNA and protein expression levels of Nrf-2,HO-1,NQO1,Gclc,Gclm and Bcl-2 were significantly decreased(P<0.05),while TNF-?,COX-2,IL-1?,NF-?B,Cytochrome C,Caspase-8 and Caspase-3 were significantly increased in NH group(P<0.05).In vitro study showed that the cell viability of HK-2 cells decreased significantly at the concentration of 100 ?g/m L(P<0.05).The ROS contents and MDA levels in HK-2 cells increased,while the SOD activities decreased,and the leakage rate of LDH increased significantly(P<0.05).The apoptosis numbers of HK-2 cells increased with the La2O3 NPs concentration,and the apoptosis rate in 100 ?g/m L group was significantly increased(P<0.05).The m RNA and protein expression levels of Nrf-2,HO-1,NQO1 and ?-GCS in100 ?g/m L group were significantly increased(P<0.05).Conclusions 1 La2O3 NPs were composed of nanosheets connected with each other to form clusters with high purity.The results showed that liver and kidney were the target organs of La2O3 NPs.2 High dose of La2O3 NPs could induce hepatotoxicity in mice,which is closely related to Nrf-2/ARE pathway,bile acid metabolism pathway and apoptosis related genes.In vitro study showed that high concentration of La2O3 NPs could induce Hep G2 cell apoptosis through oxidative stress injury.3 High doses of La2O3 NPs could induce nephrotoxicity in mice,which was closely related to the expression levels in Nrf-2/ARE signaling and apoptosis pathways.In vitro experiments showed that high concentration of La2O3 NPs induced HK-2 cytotoxicity and oxidative stress injury.Figure 53;Table 20;Reference 286... |
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