Excessive airway inflammation occurs in asthma, bronchitis and bronchiectasis. Local human bronchial epithelial (HBE) cells express chemoattractant cytokines and hematopoietic growth factors that serve to recruit immune effector neutrophils and lymphocytes, amplifying the airway inflammatory response. Molecular mechanisms regulating HBE cell expression of inflammatory cytokines will be elucidated. Stimulated HBE cells express substantial IL-8 and little IL-2, and stimulated T-cells express substantial IL-2 and little IL-8. This reciprocal expression of IL-8 and IL-2 in HBE and T-cells is regulated by transcription factors NF-kappaB and the CsA-sensitive purine-box regulator. The CsA-sensitive purine-box regulator in HBE and T-cells binds to purine-rich DNA sequences including the IL-8 NF-kappaB site and the NF-AT target site, and mediates sequence-specific transcriptional repression. Cell stimulation that mobilizes calcium triggers the conversion of the purine-box regulator from a repressor into a transcriptional activator: this conversion is most extensive in activated T-cells. The CsA-sensitive purine-box regulator in HBE and T-cells contains subunits, NF45, NF90, Ku70, Ku80, and the DNA-dependent protein kinase, catalytic subunit. The stimulation-induced structural changes in the purine-box regulator subunits which control the functional conversion from a repressor into a transcriptional activator will be identified, using immunoprecipitation, phosphopeptide mapping, and in vitro transcription experiments. The molecular mechanisms through which CsA and FK506 destabilize the purine-box regulator/NF-kappaB repressor and induce constitutive IL-8 secretion, will be elucidated. In related studies, the molecular mechanisms of action of a novel antiinflammatory drug, PG490 (triptolide), derived from a Chinese herbal remedy for arthritis, will be determined. PG490 inhibits NF-kappaB transcriptional activation and inflammatory cytokine gene expression by epithelial cells and T-cells. A signaling enzyme in HBE cells which is specifically inactivated by PG490 and which regulates NF-kappaB transcriptional activation in the nucleus will be isolated and characterized.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL062588-03
Application #
6530715
Study Section
Lung Biology and Pathology Study Section (LBPA)
Program Officer
Noel, Patricia
Project Start
2000-03-01
Project End
2004-02-29
Budget Start
2002-03-01
Budget End
2003-02-28
Support Year
3
Fiscal Year
2002
Total Cost
$336,957
Indirect Cost
Name
Stanford University
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
800771545
City
Stanford
State
CA
Country
United States
Zip Code
94305
Shi, Lingfang; Godfrey, Wayne R; Lin, Joseph et al. (2007) NF90 regulates inducible IL-2 gene expression in T cells. J Exp Med 204:971-7
Shi, Lingfang; Qiu, Daoming; Zhao, Guohua et al. (2007) Dynamic binding of Ku80, Ku70 and NF90 to the IL-2 promoter in vivo in activated T-cells. Nucleic Acids Res 35:2302-10
Anseth, Jay W; Goffin, An J; Fuller, Gerald G et al. (2005) Lung surfactant gelation induced by epithelial cells exposed to air pollution or oxidative stress. Am J Respir Cell Mol Biol 33:161-8
Zhao, Guohua; Shi, Lingfang; Qiu, Daoming et al. (2005) NF45/ILF2 tissue expression, promoter analysis, and interleukin-2 transactivating function. Exp Cell Res 305:312-23
Shi, Lingfang; Zhao, Guohua; Qiu, Daoming et al. (2005) NF90 regulates cell cycle exit and terminal myogenic differentiation by direct binding to the 3'-untranslated region of MyoD and p21WAF1/CIP1 mRNAs. J Biol Chem 280:18981-9
Vaszar, Laszlo T; Nishimura, Toshihiko; Storey, John D et al. (2004) Longitudinal transcriptional analysis of developing neointimal vascular occlusion and pulmonary hypertension in rats. Physiol Genomics 17:150-6
Nishimura, Toshihiko; Vaszar, Laszlo T; Faul, John L et al. (2003) Simvastatin rescues rats from fatal pulmonary hypertension by inducing apoptosis of neointimal smooth muscle cells. Circulation 108:1640-5
Qiu, Daoming; Kao, Peter N (2003) Immunosuppressive and anti-inflammatory mechanisms of triptolide, the principal active diterpenoid from the Chinese medicinal herb Tripterygium wilfordii Hook. f. Drugs R D 4:1-18
Nishimura, Toshihiko; Faul, John L; Berry, Gerald J et al. (2002) Simvastatin attenuates smooth muscle neointimal proliferation and pulmonary hypertension in rats. Am J Respir Crit Care Med 166:1403-8
Nishimura, T; Faul, J L; Berry, G J et al. (2001) 40-O-(2-hydroxyethyl)-rapamycin attenuates pulmonary arterial hypertension and neointimal formation in rats. Am J Respir Crit Care Med 163:498-502

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