The role of Keap1/Nrf2/HO-1 signal pathway in liver injury induced by rare earth neodymium oxide in mice / 中华劳动卫生职业病杂志

Objective: To investigate the role of Keap1/Nrf2/HO-1 signaling pathway in liver injury induced by neodymium oxide (Nd(2)O(3)) in mice. Methods: In March 2021, forty-eight SPF grade healthy male C57BL/6J mice were randomly divided into control group (0.9% NaCl), low dose group (62.5 mg/ml Nd(2)O(3)), medium dose group (125.0 mg/ml Nd(2)O(3)), and high dose group (250.0 mg/ml Nd(2)O(3)), each group consisted of 12 animals. The infected groups were treated with Nd(2)O(3) suspension by non-exposed tracheal drip and were killed 35 days after dust exposure. The liver weight of each group was weighed and the organ coefficient was calculated. The content of Nd(3+) in liver tissue was detected by inductively coupled plasma mass spectrometry (ICP-MS). HE staining and immunofluorescence was used to observe the changes of inflammation and nuclear entry. The mRNA expression levels of Keap1, Nrf2 and HO-1 in mice liver tissue were detected by qRT-PCR. Western blotting was used to detect the protein expression levels of Keap1 and HO-1. The contents of catalase (CAT), glutathione peroxidase (GSH-Px) and total superoxide dismutase (T-SOD) were detected by colorimetric method. The contents of interleukin 1β (IL-1β), interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α) were determined by ELISA. The data was expressed in Mean±SD. Two-independent sample t-test was used for inter-group comparison, and one-way analysis of variance was used for multi-group comparison. Results: Compared with the control group, the liver organ coefficient of mice in medium and high dose groups were increased, and the Nd(3+) accumulation in liver of mice in all dose groups were significantly increased (P<0.05). Pathology showed that the structure of liver lobules in the high dose group was slightly disordered, the liver cells showed balloon-like lesions, the arrangement of liver cell cords was disordered, and the inflammatory exudation was obvious. Compared with the control group, the levels of IL-1β and IL-6 in liver tissue of mice in all dose groups were increased, and the levels of TNF-α in liver tissue of mice in high dose group were increased (P<0.05). Compared with the control group, the mRNA and protein expression levels of Keap1 in high dose group were significantly decreased, while the mRNA expression level of Nrf2, the mRNA and protein expression levels of HO-1 were significantly increased (P<0.05), and Nrf2 was successfully activated into the nucleus. Compared with the control group, the activities of CAT, GSH-Px and T-SOD in high dose group were significantly decreased (P<0.05) . Conclusion: A large amount of Nd(2)O(3) accumulates in the liver of male mice, which may lead to oxidative stress and inflammatory response through activation of Keap1/Nrf2/HO-1 signal pathway. It is suggested that Keap1/Nrf2/HO-1 signal pathway may be one of the mechanisms of Nd(2)O(3) expose-induced liver injury in mice.

Research progress on the regulatory mechanism of non-coding RNA in arsenic toxicity / 中华劳动卫生职业病杂志

Arsenic is a non-metallic element, and the International Agency for Research on Cancer has identified arsenic and its compounds as carcinogens. Arsenic and its compounds can be absorbed through the respiratory tract, skin and digestive tract, distributed in the liver, kidney, lung and skin, and cause damage. Non-coding RNAs are closely related to arsenic-induced nervous system disorders, cell necrosis, reproductive toxicity, and carcinogenesis. In recent years, the network regulation of microRNAs (miRNAs) , long non-coding RNAs (lncRNAs) , and circular RNAs (circRNAs) among non-coding RNAs in various diseases induced by arsenic has become a new research field. This paper summarizes the existing scientific research results, and expounds the mechanism of miRNAs, lncRNAs and circRNAs in arsenic toxicity, and provides basic data and theoretical basis for the prevention and treatment of arsenic poisoning.

Neodymium Oxide Induces Cytotoxicity and Activates NF-κB and Caspase-3 in NR8383 Cells / 生物医学与环境科学（英文）

We investigated whether Nd2O3 treatment results in cytotoxicity and other underlying effects in rat NR8383 alveolar macrophages. Cell viability assessed by the MTT assay revealed that Nd2O3 was toxic in a dose-dependent manner, but not in a time-dependent manner. An ELISA analysis indicated that exposure to Nd2O3 caused cell damage and enhanced synthesis and release of inflammatory chemokines. A Western blot analysis showed that protein expression levels of caspase-3, nuclear factor-κB (NF-κB) and its inhibitor IκB increased significantly in response to Nd2O3 treatment. Both NF-κB and caspase-3 signaling were activated, suggesting that both pathways are involved in Nd2O3 cytotoxicity.

Research on the oxidation damage of sodium arsenite on rat lung / 中国职业医学

OBJECTIVE: To explore the oxidation damage of sodium arsenite( NaAsO_2) drinking exposure on rat lung.METHODS: Thirty-two specific pathogen free healthy adult male SD rats were randomly divided into 4 groups: control group,low-,medium- and high-dose groups,with 8 rats in each group. The 3 arsenic exposure groups were intoxicated by NaAsO_2 with mass concentrations of 10. 00,100. 00 and 1 000. 00 μg / L in drinking water,respectively,while the control group was given ultrapure water for free drinking. All the rats were sacrificed after 28 days. The total number of white blood cells and the cell death rate in bronchoalveolar lavage fluid( BALF) were measured. The level of reactive oxygen species( ROS),nicotinamide adenine dinucleotide phosphate( NADPH),the antioxidant ability and the nitric oxide( NO) level in BALF were measured by the enzyme-linked immunosorbent assay. RESULTS: The total number of white blood cells in BALF in medium-dose group was higher than those of the control group and high-dose group( P < 0. 05).The cell death rate of BALF in high-dose group was higher than those of the other groups( P < 0. 01). The ROS levels in BALF of rat lung in 3 exposure groups were higher than that of the control group( P < 0. 01). The NADPH levels in medium- and high-dose groups were higher than those of the control group and low-dose group( P < 0. 05). The total antioxidant ability in medium- and high-dose groups were lower than that of the control group( P < 0. 01). The NO levels in medium- and high-dose groups were higher than that of the control group( P < 0. 05). CONCLUSION: The NaAsO_2 exposure in rats could lead to high expression of oxidase ROS by activating NADPH followed by increasing NO level,resulting in imbalanced organism oxidation and anti-oxidation system and causing oxidative stress injury in tissues.

Study on mechanism of sodium arsenite-induced lung injury in male rats / 中国职业医学

OBJECTIVE: To observe the effects of lung injury caused by sodium arsenite in male rats,and to explore its cell senescence mechanism. METHODS: Specific pathogen free healthy adult male Wistar rats were randomly divided into 4groups with 8 rats in each group: a control group( given ultrapure water) and low-,medium- and high-sodium arsenite dose groups( 10,100 and 1 000 μg / L sodium arsenite in drinking water,respectively). The rats were euthanized after 4weeks of treatment. The pathologic changes in the lung were examined and the levels of interleukin( IL)-1β,IL-6,IL-10 and β-galactosidase( β-Gal) in broncho-alveolar lavage fluid( BALF) were determined by enzyme-linked immunosorbent assay. RESULTS: The lung tissue of the 3 treatment groups showed early inflammatory pathological changes. With the increase of dose,lung histopathology gradually showed the alveolar interval widened,infiltrating with protein-rich fluid and a large number of inflammatory cells. The levels of IL-1β,IL-6 and β-Gal in BALF of the medium- and high-dose groups were higher than those of the control group( P < 0. 05). The levels of IL-10 in BALF of the 3 treatment groups were lower than that of the control group( P < 0. 05). The levels of β-Gal and IL-1β in BALF of rats as well as with IL-6 was positively correlated [the correlation coefficient( r) were 0. 691 and 0. 410 respectively,P < 0. 05]. The levels of β-Gal and IL-10 were not correlated( r =- 0. 117,P > 0. 05). CONCLUSION: Sodium arsenite in drinking can result in inflammatory injury in lung in male rats. The mechanism may be related to the cell senescense that activates the inflammatory cascade.

Distribution and expression of p38 MAPK in the distal cerebrospinal fluid contacting neurons in brain of rat by noise stress / 中国应用生理学杂志

<p><b>AIM</b>To observe the distribution and expression of p-p38MAPK in the distal cerebrospinal fluid contacting neurons in brain of rat by noise stress.</p><p><b>METHODS</b>By a double-labelled method combing the tracing of CB-HRP and the immunohistochemical technique p-p38MAPK, the distribution and expression of p-p38MAPK in the distal cerebrospinal fluid contacting neurons(csf cn) were observed following noise stress. Expression of p-p38MAPK and double-labelled of CB-HRP/p-p38MAPK were also observed in rat brain after noise stress.</p><p><b>RESULTS</b>Two groups of CB-HRP labeled neuron clusters consistently appeared in certain regions of the brainstem but none in other regions of the brain. Without noise stress exposure, only a few neurons were found double-labeled by CB-HRP/p-p38MAPK. After 1 day noise stress exposure, only few neurons double-labeled by CB-HRP/p-p38MAPK were observed in the above-mentioned regions. After 5 days, the number of neurons double-labeled by CB-HRP/p-p38MAPK increased significantly compared with the control group (P < 0.05). After 10 days, the number of neurons double-labeled by CB-HRP/p-p38MAPK increased significantly compared with the control group (P < 0.05). After 20 days, both of the numbers of neurons double-labeled by CB-HRP/p-p38MAPK increased significantly compared with that of the control group (P < 0.01).</p><p><b>CONCLUSION</b>Two groups of distal cerebrospinal fluid contacting neuron clusters consistently existed in certain regions of the brain parenchyma, and in these clusters only a few neurons con rained p-p38MAPK. After noise stress exposure of different durations (days 1, 5, 10, 20), the number of distal cerebrospinal fluid contacting neurons with p-p38MAPK increased significantly with increasing days. The results indicate that distal cerebrospinal fluid contacting neurons are special neurons existing consistently in brain, including distal cerebrospinal fluid contacting neurons with p-p38MAPK which may participate in the whole procedure of signal transduction or central modulation in noise stress response and play greater roles with increasing days.</p>

Preparation and identification of anti human myocardium troponin I monoclonal antibodies / 第二军医大学学报

Objective: To prepare monoclonal antibodies (McAb) with cardiac troponin I (cTnI) which was purified from fresh human cardiac muscle within 6 h. Methods: (1) Extraction and purification of human cTnI: cTnI was purified by high salt extraction, saltless precipitation, 65℃ treatment, ammonium sulfate fractionation and DEAE-cellulose chromatography, etc. (2) Preparation of anti human cTnI McAb: The purified cTnI was injected into the spleen of BALB/c mice. The cTnI-primed spleen cells were fused with Sp2/0 myoloma cell. The McAbs anti human cTnI were obtained by screening with indirect ELISA and 3 times clone. (3)The identification of anti cTnI McAb. Results: Five hybridoma cell lines, named 3A7，3A11，3D2，3F10 and 1H9 were developed, which could secret McAb stably. The 5 McAbs all were demonstrated to be IgG2a by double gel diffusion test. The number of hybridoma chromosomes was between 92 to 110 and the chromosomes were mainly telocentric. Five kinds of ascites had no cross-reaction to LDH，CK，CK-MB ，AST and cardiac troponin T(cTnT), and their titers were between 3.2×10-6 to 1.6×10-7. Conclusion: 3D2，3F10 and 3A7,3A11,1H9 react to different epitopes of cTnI.

Preparation and identification of anti human myocardium troponin I monoclonal antibodies / 第二军医大学学报

Objective: To prepare monoclonal antibodies (McAb) with cardiac troponin I (cTnI) which was purified from fresh human cardiac muscle within 6 h. Methods: (1) Extraction and purification of human cTnI: cTnI was purified by high salt extraction, saltless precipitation, 65℃ treatment, ammonium sulfate fractionation and DEAE-cellulose chromatography, etc. (2) Preparation of anti human cTnI McAb: The purified cTnI was injected into the spleen of BALB/c mice. The cTnI-primed spleen cells were fused with Sp2/0 myoloma cell. The McAbs anti human cTnI were obtained by screening with indirect ELISA and 3 times clone. (3)The identification of anti cTnI McAb. Results: Five hybridoma cell lines, named 3A7，3A11，3D2，3F10 and 1H9 were developed, which could secret McAb stably. The 5 McAbs all were demonstrated to be IgG2a by double gel diffusion test. The number of hybridoma chromosomes was between 92 to 110 and the chromosomes were mainly telocentric. Five kinds of ascites had no cross-reaction to LDH，CK，CK-MB ，AST and cardiac troponin T(cTnT), and their titers were between 3.2×10-6 to 1.6×10-7. Conclusion: 3D2，3F10 and 3A7,3A11,1H9 react to different epitopes of cTnI.