• Toxicological Research
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• 제11권2호
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• pp.169-173
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• 1995

The effects of tumor necrosis factor alpha $(TNF-{\alpha})$ on growth and tubular formation of bovine aortic endothelial cells were examined using an in vitro angiogenesis model system. The growth of endothelial cells was enhanced in a dose-dependent manner when the cells were cultured with $TNF-{\alpha}$ for 3 days, but $TNF-{\alpha}$, at the concentration of 1 nM or higher, produced a growth inhibition of endothelial cells when the cells were cultured for 8 days. The endothelial cells incubated with $TNF-{\alpha}$ for 48-h exhibited a typical morphologic change. Then, they showed a fibroblastoid organization of overlapping, elongated, and spindle-shaped cells. $TNF-{\alpha}$, at the concentration of O. 1 nM or higher, inhibited the tubular formation of vascular endothelial cells in an in vitro anglogenesis model using a 3-dimensional culture system.

• Journal of Life Science
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• 제12권2호
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• pp.57-60
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• 2002

Apoptosis of vascular smooth muscle cell is observed in the vascular diseases such as atherosclerosis and restenosis. The death of vascular smooth muscle cells can be induced by cytokines and activation of Fas-pathways. It is widely accepted that apoptosis occurs without inflammation. There are, however, reports that apoptosis is not silent. Vascular smooth muscle cells dying by Fas-pathway secreted inflammatory cytokines including monocyte chemoattractant protein-1. This study have investigated whether apoptosis is associated with potent inflammatory cytokine tumor tumor necrosis factor (TNF)-${\alpha}$. The cells which undergo apoptosis by expressing FADD in the absence of tetracycline expressed and secreted TNF-${\alpha}$. When the level of TNF-${\alpha}$ transcript was investigated, dying smooth muscle cells exhibited transcriptional activation of TNF-${\alpha}$. The data indicate that dying vascular smooth muscle cells contribute to inflammation by expressing inflammatory cytokines. The present study suggests that apoptosis could not be silent in certain pathological situations.

• Archives of Pharmacal Research
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• 제22권4호
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• pp.348-353
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• 1999

Possible antiinflammatory effect of eudesmin were examined by assessing the effects on tumor necrosis factor (TNF)-$\alpha$ production and lymphocyte proliferation as well as cytotoxicity against murine and human macrophages. the compound significantly inhibited TNF-$\alpha$, production by lipopolysaccaride (LPS)-stimulated murine macrophage RAW264.7 without displaying cytotoxicity suggesting that eudesmin may inhibit TNF-$\alpha$ production without any interference of normal cell function. It also significantly attenuated T cell proliferation stimulated by concanavalin A (Con A) in a dose-dependent manner.

• Toxicological Research
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• 제9권2호
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• pp.177-186
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• 1993

Previous results from several laboratories have demonstrated that tumor necrosis factor-alpha (TNFalpha) depressed cytochrome P-450 (P-450)-dependent drug metabolism in vivo. However, there is some debate whether the action of TNFalpha is mediated by its direct effects on hepatocytes, or is indirectly mediated through the release of other mediators like IL-1 from macrophages. In the present studies, we investigated the effects of TNFalpha on P-450-dependent drug metabolizing enzyme as measured by 7-ethoxyresorufin O-deethylase (EROD) activity.

• BMB Reports
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• 제42권5호
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• pp.260-264
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• 2009

Tumor necrosis factor-$\alpha$ (TNF-$\alpha$) exhibits cytotoxicity towards various tumor cells in vitro and induces apoptotic necrosis in transplanted tumors in vivo. It also shows severe toxicity when used systemically for the treatment of cancer patients, hampering the development of TNF-$\alpha$ as a potential anticancer drug. In order to understand the structure-function relation of TNF-$\alpha$ with respect to receptor binding, we selected four regions on the bottom of the TNF-$\alpha$ trimer that are in close contact with the receptor and carried out mutagenesis studies and computational modeling. From the study, various TNF-$\alpha$ muteins with a high therapeutic index were identified. These results will provide a structural basis for the design of highly potent TNF-$\alpha$ for therapeutic purposes. By conjugating TNF-$\alpha$ muteins with a high therapeutic index to a fusion partner, which targets a marker of angiogenesis, it could be possible to develop TNF-$\alpha$ based anticancer drugs.

• Journal of Life Science
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• 제17권1호
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• pp.45-50
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• 2007

This study investigated biological activity of tumor necrosis factor $(TNF)-\alpha$ secreted from smooth muscle cell (SMC) destined for death by expressing Fas associated death domain containing protein (FADD) (FADD-SMC) when the cells are grown without tetracycline in culture medium. In the absence of tetracycline the FADD-SMC secreted approximately 1000 pg/ml $TNF-\alpha$, whereas hardly detectable amount of the cytokine existed in the presence of tetracycline. The culture medium collected from the FADD-SMC grown in the absence of tetracycline increased phosphorylated form of p38 MAPK and up-regulated nuclear factor kappa B (NF-kB). The medium collected without tetracycline also caused death of L929 cells. Depletion of $TNF-\alpha$ with the soluble TNF receptor (sTNFR) inhibited the phosphorylation of p38 MAPK, the up-regulation of NF-kB activity and the death activity of the medium collected from FADD-SMC in the absence of tetracycline. These results indicate that $TNF-\alpha$ secreted from SMC undergoing death is biologically active and can affect cellular function.

• Journal of Periodontal and Implant Science
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• 제20권2호
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• pp.167.1-167.1
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• 1990

• 대한생식의학회:학술대회논문집
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• 대한불임학회 1999년도 제38차 추계 학술대회
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• pp.83.1-83.1
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• 1999

• BMB Reports
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• 제28권1호
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• pp.46-50
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• 1995

Three kinds of mouse tumor necrosis factor (TNF), which have molecular weights of 35 kDa, 45 kDa, and 18 kDa on SDS-PAGE, were partially purified from serum-free culture supernatants of mouse peritoneal macrophages induced with lipopolysaccharide. Analysis of the native molecular weights by gel filtration indicated that the 18 kDa and 45 kDa TNFs aggregate into 50 kDa and 100 kDa molecules, respectively, while the 35 kDa TNF is contained in high molecular weight aggregates of approximately 200 kDa. The three kinds of cytotoxic factors all elicited tumor reducing responses.

• Journal of Chest Surgery
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• 제32권11호
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• pp.971-977
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• 1999

Background: Immunologic and inflammatory responses of cardiopulmonary bypass(CPB) influence postoperative mortality and morbidity with multiple organ injury. It has been reported that ischemia/reperfusion induced-myocardial injury during CPB is causative of release of inflammatory cytokines such as interleukin-6(IL-6) and tumor necrosis factor-$\alpha$ (TNF-$\alpha$). The purpose of this study was to detect the time course of the activated cytokine and troponin-T(TnT), and to examine the correlation between such parameters during CPB. Material and Method: The serial samples were collected from arterial blood via radial arterial catheter in 23 patients who are underwent open heart surgery (OHS) with CPB, the IL-6, TNF-$\alpha$ and TnT were checked. Result: \circled1 IL-6, TNF$\alpha$- and TnT concentration increased significantly during CPB with a peaking level of CPB-off (p 0.05). \circled2 IL-6 had highly positive correlation with aortic cross clamping time and total bypass time(r=0.80, 0.78; p 0.05, respectively). \circled3 There was no correlation among IL-6, TNF-$\alpha$ and TnT. Conclusion: In conclusion, these data showed that elevated production of serum IL-6 during CPB was attributable to ischemia/reperfusion induced-myocardial damage. IL-6 will become a new and sensitive biological marker in assessment of myocardial damage during OHS with CPB. However, further studies will be needed to apply IL-6 in more patient population.