Int J Med Sci 2018; 15(6):595-602. doi:10.7150/ijms.23786 This issue Cite
Research Paper
1. Division of Critical Care Medicine, Union Hospital of Fujian Medical University, Fuzhou, Fujian, China 350001
2. Department of Vascular Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115
3. Deparment of Anesthesiology, Fujian Renmin Hospital, Fuzhou, Fujian, China 350001
4. Department of Cardiology, Shaanxi Provincial People's Hospital, Xi'an, Shaanxi, China 710068
5. Department of Nephrology, Qianfoshan Hospital, Shandong University, Jinan, Shandong, China 250014
Background: The morbidity of sepsis induced acute kidney injury remains unacceptable high and the mechanisms of that disease remains unclear. For urine backleak and intercellular tight junction among tubular epithelial cells (TECs) destruction often occur during sepsis induced acute kidney injury, we examined whether lipopolysaccharide could damage intercellular tight junction among TECs and associated mechanisms in our present study.
Methods: HK-2 cells were cultured, transfected with different SiRNAs and stimulated with LPS and PYR-41. Transepithelial Permeability Assay and Transepithelial Electrical Resistance Assay were used to evaluate intercellular tight junction destruction and Western Blot and Immunofluorescence were used to evaluate proteins expression.
Results: Transepithelial Permeability increased significantly (P<0.05) and Transepithelial Electrical Resistance reduced remarkably (P<0.05) of the monolayer TECs stimulated with LPS. The expression of JAM-3 and RhoT1 decreased significantly (P<0.05) in TECs stimulated with LPS, while the level of SMAD-4 increased significantly (P<0.05). Downregulation of the expression of SMAD-4 with RNA interference could increase the expression of JAM-3 in LPS treated TECs. Moreover, upregulation of RhoT1 level by decreased the degradation of RhoT1 could decrease the expression of SMAD-4 and increase the JAM-3 level in TECs treated with LPS, while downregulation of RhoT1 level with RNA interference had the opposite effects.
Conclusion: LPS mediates intercellular tight junction destruction among TECs and RhoT1/SMAD-4/JAM-3 is a pivotal pathway to mediate the phenomenon.