title: Involvement of the nuclear factor-κB pathway in the adhesion of neutrophils to renal tubular cells after injury induced by neonatal postasphyxial serum.
abstract: Nuclear factor κB (NF-κB) plays an important role in the regulation of inflammatory proteins. However, it is unclear whether the NF-κB/intercellular adhesion molecule-1 (ICAM-1) pathway is involved in the adhesion of neutrophils and renal injury after hypoxia-ischemia (HI) in neonates. In this report we investigated whether NF-κB and its downstream molecule ICAM-1 were involved in renal injury induced by postasphyxial serum (PS) from neonates. Human renal proximal tubular (HK-2) cells were preincubated with 10 % fetal calf serum (control), 20 % neonatal PS, or 20 % PS plus pyrolidine dithiocarbamate (PDTC). The expression of IκBα, NF-κB p65, and ICAM-1 in HK-2 cells was determined by Western blot and/or immunohistochemistry. Nuclear translocation of NF-κB p65 in HK-2 cells was detected by immunofluorescence and Western blot. The ICAM-1 mRNA was determined by RT-PCR. Then HK-2 cells were cultured with neutrophils from neonates with asphyxia. After HK-2 cells had been cultured with neutrophils, we detected myeloperoxidase (MPO) activity, the leakage rate of lactate dehydrogenase (LDH), and cell viability. We found that PS preincubation resulted in significantly decreased IκBα expression and increased expression of NF-κB and ICAM-1, and facilitated the nuclear translocation of NF-κB in HK-2 cells. PS preincubation increased MPO activity, leading to elevated leakage rates of LDH and decreased cell viability after neutrophil exposure. Furthermore, the inhibition of NF-κB activity by PDTC significantly upregulated IκBα expression, decreased NF-κB and ICAM-1 expression, downregulated the nuclear translocation of NF-κB, and decreased MPO activity. This leads to decreased leakage rates of LDH and increased cell viability after neutrophil exposure. Our findings suggest that NF-κB/ICAM-1 pathway may be involved in neutrophil-endothelial interactions and neonatal renal injury after HI.
authors.affiliation: Department of Newborn Medicine, Affiliated Hospital of Luzhou Medical College, No. 25, Tai Ping Road, Luzhou, 646000, Sichuan, People's Republic of China.
authors.forename: Tao
authors.initials: T
authors.lastname: Xiong
authors.forename: Wenbin
authors.initials: W
authors.lastname: Dong
authors.forename: Hui
authors.initials: H
authors.lastname: Fu
authors.forename: Qingping
authors.initials: Q
authors.lastname: Li
authors.forename: Cunliang
authors.initials: C
authors.lastname: Deng
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Lei
authors.forename: Lin
authors.initials: L
authors.lastname: Guo
mesh_terms: D001238:Asphyxia Neonatorum; D002448:Cell Adhesion / Q000276:immunology*; D015687:Cell Hypoxia; D002460:Cell Line; D002470:Cell Survival; D006801:Humans; D020672:I-kappa B Proteins / Q000096:biosynthesis; D007231:Infant, Newborn; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D007684:Kidney Tubules / Q000166:cytology / Q000293:injuries / Q000378:metabolism*; D007770:L-Lactate Dehydrogenase; D000072000:NF-KappaB Inhibitor alpha; D009504:Neutrophils / Q000276:immunology*; D009195:Peroxidase; D012333:RNA, Messenger / Q000096:biosynthesis; D015427:Reperfusion Injury / Q000378:metabolism; D051996:Transcription Factor RelA / Q000096:biosynthesis / Q000378:metabolism*
chemical_list: D020672:I-kappa B Proteins; C573420:ICAM1 protein, human; C000606204:NFKBIA protein, human; C498143:RELA protein, human; D012333:RNA, Messenger; D051996:Transcription Factor RelA; D018799:Intercellular Adhesion Molecule-1; D000072000:NF-KappaB Inhibitor alpha; D007770:L-Lactate Dehydrogenase; D009195:Peroxidase