title: 15-Deoxy-Δ(12,14)-prostaglandin J(2) modulates lipopolysaccharide-induced chemokine expression by blocking nuclear factor-κB activation via peroxisome proliferator activated receptor-γ-independent mechanism in renal tubular epithelial cells.
abstract: OBJECTIVE
  Inflammation is an unavoidable milieu for renal tubular cells during the development of renal tubulointerstitial fibrosis. It has been demonstrated that chemokines including monocyte chemoattractant protein-1 (MCP-1) and IL-8 are related to tubulointerstitial lesions. 15d-PGJ2 may modulate renal tubulointerstitial fibrosis progression via anti-inflammatory effects. However, no information is known about the effects of 15d-PGJ2 on chemokine expression in human proximal renal tubular cells (HPTECs) under inflammation.
  
  
  METHODS
  In the present study, HPTECs (HK-2 cells) were stimulated with lipopolysaccharide (LPS) only, or preincubated with 15d-PGJ2. IL-8 and MCP-1 expressions were determined by real-time PCR and ELISA. Nuclear factor-κB (NF-κB) location was detected by immunofluorescence analysis. The p-IKK, p-IκBα and p65/p50 were analyzed by immunoblotting. To investigate the mechanism of inhibitory effects of 15d-PGJ2, the PPAR-γ gene was effectively silenced in HK-2 cells using specific siRNA.
  
  
  RESULTS
  The results showed that application of LPS significantly increased IL-8 and MCP-1 production. Phosphorylation of IκBα, IKK and nucleus translocation of NF-κB significantly increased in LPS-stimulated HK-2 cells. 15d-PGJ2 downregulated LPS-induced IL-8 and MCP-1 production. Interestingly, in PPAR-γ-deficient HK-2 cells, 15d-PGJ2 was still capable of inhibiting chemokines expression and attenuating phosphorylation of IκBα and nucleus translocation of NF-κB.
  
  
  CONCLUSIONS
  Collectively, these results suggest that 15d-PGJ2 exerts anti-inflammatory actions on HK-2 cells by attenuating chemokines expression. 15d-PGJ2 inhibits chemokines expression via a PPAR-γ-independent way, which is related to block NF-κB pathway. Since NF-κB is an important regulator of the response of HPTECs to injury, PPAR-γ agonists may represent a key pharmacological target for ameliorating inflammation-associated tubulointerstitial fibrosis.
authors.affiliation: Department of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University, Shanghai, PR China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Lu
authors.forename: Qiao
authors.initials: Q
authors.lastname: Zhou
authors.forename: Fang
authors.initials: F
authors.lastname: Zhong
authors.forename: Shanmai
authors.initials: S
authors.lastname: Guo
authors.forename: Xu
authors.initials: X
authors.lastname: Hao
authors.forename: Cong
authors.initials: C
authors.lastname: Li
authors.forename: Weiming
authors.initials: W
authors.lastname: Wang
authors.forename: Nan
authors.initials: N
authors.lastname: Chen
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000187:drug effects; D002460:Cell Line; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism; D018932:Chemokine CCL2 / Q000235:genetics / Q000378:metabolism; D018925:Chemokines / Q000235:genetics / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D004847:Epithelial Cells / Q000187:drug effects* / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D020672:I-kappa B Proteins / Q000378:metabolism; D015151:Immunoblotting; D016209:Interleukin-8 / Q000235:genetics / Q000378:metabolism; D007687:Kidney Tubules, Proximal / Q000166:cytology; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008856:Microscopy, Fluorescence; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000378:metabolism*; D047495:PPAR gamma / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D015230:Prostaglandin D2 / Q000031:analogs & derivatives* / Q000494:pharmacology; D034622:RNA Interference; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects
chemical_list: C097240:15-deoxy-delta(12,14)-prostaglandin J2; D018932:Chemokine CCL2; D018925:Chemokines; D020672:I-kappa B Proteins; D016209:Interleukin-8; D008070:Lipopolysaccharides; D016328:NF-kappa B; C000606204:NFKBIA protein, human; D047495:PPAR gamma; D000072000:NF-KappaB Inhibitor alpha; D015230:Prostaglandin D2