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Ambient air pollution is a leading cause of non-communicable disease in the world. PM 2.5 has the potential to change the miRNAs profiles, which in turn causes cardiovascular effects. Hypoxia-inducible factor (HIF)-1 plays a critical role in the development of atherosclerosis. Yet, the possible role of miR-939-5p/HIF-1α in PM 2.5 -induced endothelial injury remains elusive. Therefore, the study aims to investigate the effects of miR-939-5p and HIF-1α on PM 2.5 -triggered endothelial injury. The results from immunofluorescence, qRT-PCR, LSCM, and western blot assays demonstrated that PM 2.5 increased the levels of HIF-1α, inflammation and apoptosis in human aortic endothelial cells (HAECs). Yet, the inflammatory response and mitochondrial-mediated apoptosis pathway were effectively inhibited in HIF-1α knockdown HAECs lines. The expression of miR-939-5p was significantly down-regulated in HAECs after exposed to PM 2.5 . The luciferase reporter, qRT-PCR and western blot results demonstrated that miR-939-5p could directly targeted HIF-1α. And the miR-939-5p overexpression restricted PM 2.5 -triggered decreases in cell viability and increases in lactic dehydrogenase (LDH) activity, reactive oxygen species (ROS), mitochondrial membrane potential (MMP) and inflammation. In addition, miR-939-5p overexpression remarkably suppressed PM 2.5 -triggered BcL-2/Bax ratio reduction and Cytochrome C, Cleaved Caspase-9 and Cleaved Caspase-3 expression increase, revealed that miR-939-5p hampered PM 2.5 -induced endothelial apoptosis through mitochondrial-mediated apoptosis pathway. Our results demonstrated that PM 2.5 increased the expression of HIF-1α followed by a pro-inflammatory and apoptotic response in HAECs. The protective effect of miR-939-5p on PM 2.5 -triggered endothelial cell injury by negatively regulating HIF-1α. miR-939-5p might present a new therapeutic target for PM 2.5 induced endothelial injury.

Epidemiological evidence showed that the particulate matter exposure is associated with atherosclerotic plaque progression, which may be related to foam cell formation, but the mechanism is still unknown. The study was aimed to investigate the toxic effects and possible mechanism of PM 2.5 on the formation of macrophage foam cells induced by oxidized low density lipoprotein (ox-LDL). Results showed that PM 2.5 induced cytotoxicity by decreasing the cell viability and increasing the LDH level in macrophage foam cells. PM 2.5 aggravated the lipid accumulation in ox-LDL-stimulated macrophage RAW264.7 within markedly increasing level of intracellular lipid by Oil red O staining. The level of ROS increased obivously after co-exposure to PM 2.5 and ox-LDL than single exposure group. In addition, serious mitochondrial damage such as the mitochondrial swelling, cristae rupturing and disappearance were observed in macrophage foam cells. The loss of the mitochondrial membrane potential (MMP) further exacerbated the mitochondrial damage in PM 2.5 -induced macrophage foam cells. The apoptotic rate increased more severely via up-regulated protein level of Bax, Cyt C, Caspase-9, Caspase-3, and down-regulated that of Bcl-2, indicating that PM 2.5 activated the mitochondrial-mediated apoptosis pathway. In summary, our results demonstrated that PM 2.5 aggravated the lipid accumulation, mitochondrial damage and apoptosis in macrophage foam cells, suggesting that PM 2.5 was a risk factor of atherosclerosis progression., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Objective To explore the effect of hyperoxia on the expressions of CCAAT enhancer binding protein α (C/EBPα) and pulmonary surfactant proteins (SP-A, SP-B, SP-C, SP-D) and their correlations in primary type II alveolar epithelial cells (AECIIs) from premature rats. Methods AECIIs were divided into an air control group and a hyperoxia model group. The cells of the two groups were respectively exposed toair and 950 mL/L O 2 . The cells were harvested at 24, 48, and 72 hours after exposure. Inverted phase-contrast microscope was used to observe morphological changes of the cells. Real-time quantitative PCR and Western blotting were performed to measure the mRNA and protein expressions of C/EBPα, SP-A, SP-B, SP-C and SP-D. Cell Counting Kit-8 (CCK-8) was applied to detect the proliferation of AECIIs. Results With the prolonging incubation time, the air group showed a significantly decreasing mRNA and protein expressions of C/EBPα, and significantly ascending mRNAand protein expressions of SP-A, SP-B, SP-C, SP-D and increasing proliferation of AECIIs. The mRNA and protein expressions of SP-A, SP-B, SP-C, SP-D and the proliferation of AECIIs in the hyperoxia group showed a trend of increasing at first and then decreasing as the culture time went on. Compared with the air group, the hyperoxia group showed significantly increased mRNA and protein expressions of C/EBPα and SP-A, SP-B, SP-C, SP-D and enhanced proliferation of AECIIs at 48 hours. In the hyperoxia group, the protein expression of C/EBPα was positively correlated with the protein expressions of SP-A, SP-B, SP-C, SP-D as well as the proliferation of AECIIs(r=0.96, 0.98, 0.92, 0.97, 0.90). Conclusion In the early stage of hyperoxia exposure, C/EBPα can promote the secretion of pulmonary surfactant protein to participate in the body's protective regulation. However, over the time of hyperoxia exposure, C/EBPα loses compensatory protective effect.

Objective: To evaluate the effect of bleomyin A5 combined with phosphorus-32 colloid in the treatment of mucocele., Methods: A total of 214 patients divided into three groups, bleomyin A5 (50 cases), phosphorus-32 colloid (50 cases) and bleomyin A5 combined with phosphorus-32 colloid (114 cases)., Results: The efficacy of bleomyin A5 group, phosphorus-32 colloid group, and bleomyin A5 combined with phosphorus-32 colloid group was 84% (42/50), 82% (41/50) and 98% (112/114), respectively. There were significant difference in efficacy among the three groups (P < 0.05). The phosphorus-32 colloid group and the bleomyin A5 group had no significant difference in efficacy (P > 0.05)., Conclusions: The independent use of bleomyin A5 and phosphorus-32 colloid is effective, but the combined use of the two methods is more effective.