title: A synthetic peptide derived from A1 module in CRD4 of human TNF receptor-1 inhibits binding and proinflammatory effect of human TNF-alpha.
abstract: Tumour necrosis factor alpha (TNF-alpha) is a proinflammatory cytokine, which has been shown to be a causative factor in rheumatoid arthritis, inflammatory bowel disease and septic shock. Proinflammatory effect of TNF-alpha is activated mainly through human TNF receptor-1 (TNF-R1). However, the role of the fourth cystein-rich domain (CRD4) of TNF-R1 extracellular portion in the interaction of TNF-alpha with TNF-R1 is still unclear. In the present study, binding activity of TNF-alpha to TNF-R1 and protein levels of IkappaB-alpha and nuclear transcription factor kappa B (NF-kappaB) p65 subunit in HeLa cells were measured using enzyme-linked immunosorbent assay (ELISA) and western-blot analysis. Pep 3 (LRENECVS) which was derived from the hydrophilic region of A1 module in CRD4 remarkably inhibited the binding of TNF-alpha to TNF-R1, and also reversed TNF-alpha-induced degradation of IkappaB-alpha and nuclear translocation of NF-kappaB p65 subunit in HeLa cells. Our results confirmed that the hydrophilic region of A1 module in CRD4 participated in the interaction of TNF-alpha with TNF-R1, and demonstrated the potential of small-molecule TNF-alpha extracellular inhibitors targeting at A1 module in CRD4 of TNF-R1 in suppressing proinflammatory effect of TNF-alpha.
authors.affiliation: School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, People's Republic of China.
authors.forename: Yingnan
authors.initials: Y
authors.lastname: Cao
authors.forename: Zhaohe
authors.initials: Z
authors.lastname: Wang
authors.forename: Xianzhang
authors.initials: X
authors.lastname: Bu
authors.forename: Shu
authors.initials: S
authors.lastname: Tang
authors.forename: Zhengrong
authors.initials: Z
authors.lastname: Mei
authors.forename: Peiqing
authors.initials: P
authors.lastname: Liu
mesh_terms: D001665:Binding Sites; D006367:HeLa Cells; D006801:Humans; D020672:I-kappa B Proteins / Q000032:analysis; D007249:Inflammation / Q000517:prevention & control*; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000032:analysis; D010446:Peptide Fragments / Q000138:chemical synthesis / Q000494:pharmacology* / Q000627:therapeutic use; D011485:Protein Binding / Q000187:drug effects; D047888:Receptors, Tumor Necrosis Factor, Type I / Q000737:chemistry* / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors* / Q000378:metabolism
chemical_list: D020672:I-kappa B Proteins; D016328:NF-kappa B; C000606204:NFKBIA protein, human; D010446:Peptide Fragments; D047888:Receptors, Tumor Necrosis Factor, Type I; D014409:Tumor Necrosis Factor-alpha; D000072000:NF-KappaB Inhibitor alpha