Effect of surfactant protein A on lipopolysaccharide-induced tumor necrosis factor-α expression in human proximal tubular epithelial cells / 中华医学杂志(英文版)
Chinese Medical Journal
; (24): 343-347, 2014.
Article
in En
| WPRIM
| ID: wpr-317990
Responsible library:
WPRO
ABSTRACT
<p><b>BACKGROUND</b>Surfactant protein A (SP-A) contributes to the regulation of sepsis-induced acute lung injury. In a previous study, we demonstrated the expression and localization of SP-A in the kidneys. The present study evaluated the effect of SP-A on lipopolysaccharide (LPS)-induced tumor necrosis factor-a (TNF-α) expression and its underlying mechanisms in the human renal tubular epithelial (HK-2) cells.</p><p><b>METHODS</b>Indirect immunofluorescence assay was used to detect SP-A distribution and expression in HK-2 cells. HK-2 cells were treated with various concentrations of LPS (0, 0.1, 1, 2, 5, and 10 mg/L) for 8 hours and with 5 mg/L LPS for different times (0, 2, 4, 8, 16, and 24 hours) to determine the effects of LPS on SP-A and TNF-α expression. Then, HK-2 cells were transfected with SP-A siRNA to analyze nuclear factor κB (NF-κB) P65 and TNF-α expression of HK-2 cells after LPS-treatment.</p><p><b>RESULTS</b>Indirect immunofluorescence assay revealed that SP-A is localized to the membrane and cytoplasm of HK-2 cells. Interestingly, SP-A1/SP-A2 and TNF-a expression were found to be significantly increased in HK-2 cells upon LPS treatment. Transfection of LPS-treated HK-2 cells with SP-A siRNA resulted in significant increases in the levels of NF-κB P65 protein and TNF-α mRNA and protein compared to those in non-transfected LPS-treated HK-2 cells.</p><p><b>CONCLUSION</b>SP-A plays an important role in protecting cells against sepsis-induced acute kidney injury by inhibiting NF-κB activity to modulate LPS-induced increase in TNF-α expression.</p>
Full text:
1
Database:
WPRIM
Main subject:
Pharmacology
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Cell Line
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Lipopolysaccharides
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Tumor Necrosis Factor-alpha
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Fluorescent Antibody Technique, Indirect
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Cell Biology
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Pulmonary Surfactant-Associated Protein A
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Epithelial Cells
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Kidney Tubules, Proximal
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Metabolism
Limits:
Humans
Language:
En
Journal:
Chinese Medical Journal
Year:
2014
Document type:
Article