Hangjun Wang
University of Nebraska Medical Center
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Hangjun Wang.
In Vitro Cellular & Developmental Biology – Animal | 2001
Yunkui Zhu; Takeshi Umino; X. D. Liu; Hangjun Wang; Debra J. Romberger; John R. Spurzem; S. I. Rennard
SummaryRemodeling of extracellular matrix involves a number of steps including the recruitment, accumulation, and eventual apoptosis of parenchymal cells as well as the production, organization, and rearrangement of extracellular matrix produced by these cells. The culture of fibroblasts in three-dimensional gels made of type I collagen has been used as a model of tissue contraction which characterizes both wound repair and fibrosis. The current study was designed to determine the effect of initial collagen concentration on the ability of fibroblasts to contract collagen gels and on cell survival. Native type I collagen was extracted from rat tail tendons and used to prepare collagen gels with varying collagen concentration (0.75–2.0 mg/ml). Human lung fibroblasts (HFL-1) were cast into the gels and cultured in Dulbecco modified Eagle medium with 0.1% fetal calf serum for 2 wk. The gel size, collagen content, and deoxyribonucleic acid (DNA) content were determined. Gels prepared with an initial concentration of 0.75 mg/ml contracted more rapidly and to a smaller final size than gels prepared from 2 mg/ml initial collagen concentration (final size 7.1 versus 36.4% of initial size, P <0.01). There was no significant degradation of the collagen in the gels under either condition. Hence, the dramatically increased contraction of the lower density gels resulted in a higher final density (P<0.01). Cell density was estimated from DNA content. In low initial density gels, the final DNA content was significantly less than that in higher initial density gels (0.73 versus 1.88 μg/gel, P<0.05). This was accompanied by an increased percentage of apoptotic cells at day 14 (43.3 versus 34.1%, P<0.05). If the gels were maintained in the attached state which largely prevents contraction, apoptosis was significantly reduced, suggesting that contraction rather than matrix composition was a requirement for the increased apoptosis. In summary, these findings indicate that the initial matrix composition can lead to differing outcomes during fibroblast-mediated wound contraction.
Inflammation | 2001
Fu Qiang Wen; C. Magnus Sköld; Xiang Der Liu; Ronald F. Ertl; Yun Kui Zhu; Tadashi Kohyama; Hangjun Wang; Stephen I. Rennard
TGF-β plays a central role in the initiation and progression of pulmonary fibrosis. Glucocorticoids are frequently used to treat fibrotic diseases, but beneficial effects are often modest. Both TGF-β and glucocorticoids have been reported to increase fibroblast contraction of native collagen gels, a model of fibrotic tissue remodeling. Therefore, we sought to determine how glucocorticoids interact with TGF-β in this system. In this study, human fetal lung fibroblasts (HFL-1) were pretreated with or without TGF-β for 72 h before they were cast into type I collagen gels. Various concentrations of glucocorticoids (budesonide or hydrocortisone) were added at the time of casting. Gel size was then monitored at different times after gel release. The surrounding media were collected for the assay of prostaglandin E2 (PGE2) and the cell lysates were analyzed for cyclooxygenase (COX) expression by immunoblot. Glucocorticoids alone significantly enhanced fibroblast-mediated contraction of collagen gels (P < 0.01) and dose-dependently inhibited PGE2 release by HFL-1 fibroblasts. TGF-β significantly augmented gel contraction but also induced a 30% increase in PGE2 release and increased the expression of COX-1. Glucocorticoids inhibited TGF-β1 induced-PGE2 release, and enhanced TGF-β augmented gel contraction without significantly affecting TGF-β augmented COX-1 expression. Indomethacin, a COX inhibitor, increased TGF-β augmented gel contraction but had no further effect when added together with glucocorticoids. Thus, glucocorticoids can synergize with TGF-β in augmenting fibroblast mediated collagen gel contraction through the inhibition of PGE2 production. Such interactions between glucocorticoids and TGF-β may account, in part, for the lack of response of fibrotic diseases to glucocorticoids.
American Journal of Respiratory Cell and Molecular Biology | 2001
Hangjun Wang; Xiangde Liu; Takeshi Umino; C. Magnus Sköld; Yunkui Zhu; Tadashi Kohyama; John R. Spurzem; Debra J. Romberger; Stephen I. Rennard
American Journal of Respiratory Cell and Molecular Biology | 2002
Tadashi Kohyama; Xiangde Liu; Fu-Qiang Wen; Yun Kui Zhu; Hangjun Wang; Hui Jung Kim; Hajime Takizawa; Lenora B. Cieslinski; Mary S. Barnette; Stephen I. Rennard
American Journal of Respiratory Cell and Molecular Biology | 2002
Fu-Qiang Wen; Tadashi Kohyama; Xiangde Liu; Yun Kui Zhu; Hangjun Wang; Hui Jun Kim; Tetsu Kobayashi; Shinji Abe; John R. Spurzem; Stephen I. Rennard
American Journal of Physiology-lung Cellular and Molecular Physiology | 2002
Xiangde Liu; Tadashi Kohyama; Hangjun Wang; Yun Kui Zhu; Fu Qiang Wen; Hui Jung Kim; Debra J. Romberger; Stephen I. Rennard
American Journal of Respiratory Cell and Molecular Biology | 2001
Yun Kui Zhu; X. D. Liu; Magnus C. Sköld; Takeshi Umino; Hangjun Wang; Debra J. Romberger; John R. Spurzem; Tadashi Kohyama; Fu-Qiang Wen; Stephen I. Rennard
American Journal of Physiology-lung Cellular and Molecular Physiology | 2001
Yunkui Zhu; X. D. Liu; C. M. Skold; Takeshi Umino; Hangjun Wang; John R. Spurzem; Tadashi Kohyama; Ronald F. Ertl; S. I. Rennard
American Journal of Physiology-lung Cellular and Molecular Physiology | 2003
Hangjun Wang; Xiangde Liu; Takeshi Umino; Tadashi Kohyama; Yun Kui Zhu; Fu Qiang Wen; John R. Spurzem; Debra J. Romberger; Hui Jung Kim; Stephen I. Rennard
Journal of Laboratory and Clinical Medicine | 2001
X. D. Liu; Yunkui Zhu; Takeshi Umino; John R. Spurzem; Debra J. Romberger; Hangjun Wang; Elizabeth C. Reed; S. I. Rennard