• BMB Reports
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• 제35권3호
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• pp.267-272
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• 2002

TNF-$\alpha$ elicits various responses including apoptosis, proliferation, and differentiation according to cell type. In neuronal PC12 cells, TNF-$\alpha$ induces moderate apoptosis while lipopolysarccaharide or trophic factor deprivation can potentiate apoptosis that is induced by TNF-$\alpha$. TNF-$\alpha$ initiates various signal transduction pathways leading to the activation of the caspase family, NF-${\kappa}B$, Jun N-terminal kinase, and p38 MAPK via the death domain that contains the TNF-$\alpha$ receptor. Inhibition of translation using cycloheximide greatly enhanced the apoptotic effect of TNF-$\alpha$. This implies that the induction of anti-apoptotic genes for survival by TNF-$\alpha$ may be able to protect PC12 cells from apoptosis. Accordingly, Bcl-2, an anti-apoptotic genes for survival by TNF-$\alpha$ may be able to protect PC12 cells from apoptosis. Accordingly, Bcl-2, an anti-apoptotic Bcl-2 family member, was highly expressed in response to TNF-$\alpha$. In this study, we examined the anti-apoptotic role of p38 MAPK that is activated by TNF-$\alpha$ in neuronal PC12 cells. The phosphorylation of p38 MAPK in response to TNF-$\alpha$ slowly increased and lasted several hours in the PC12 cell and DRG neuron. This specific inhibitor of p38 MAPK, SB202190, significantly enhanced the apoptosis that was induced by TNF-$\alpha$ in PC12 cells. This indicates that the activation of p38 MAPK could protect PC12 cells from apoptosis since there is no known role of p38 MAPK in resoonse to TNF-$\alpha$ in neuron. This discovery could be evidence for the neuroprotective role of the p38 MAPK.

• IMMUNE NETWORK
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• 제11권6호
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• pp.424-427
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• 2011

The nucleotide-oligomerization domain (NOD) proteins are members of the NOD-like receptor (NLR) family, which are intracellular and cytoplasmic receptors. We analyzed the role of NODs for cytokine production by macrophages infected with intracellular pathogen M. leprae, the causative agent of leprosy. Production of pro-inflammatory cytokines such as IL-$1{\beta}$ and TNF-${\alpha}$ was inhibited in the presence of cytochalasin D, an agent blocking phagocytosis, suggesting that intracellular signaling was, partially, required for macrophage activation to M. leprae infection. Next, we investigated the role of NOD1 and NOD2 proteins on NF-${\kappa}B$ activation and cytokine expression. Treatment with M. leprae significantly increased NF-${\kappa}B$ activation and expression of TNF-${\alpha}$ and IL-$1{\beta}$ in NOD1- and NOD2-transfected cells. Interestingly, their activation and expression were inhibited by cytochalasin D, suggesting that stimulation of NOD proteins may be associated with the enhancement of cytokine production in host to M. leprae.

• 대한의생명과학회지
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• 제24권3호
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• pp.213-220
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• 2018

Triglyceride (TG) is known to be associated with inflammatory disease including atherosclerosis. In a variety of atherosclerosis models, T lymphocytes are localized in the earliest lesions of atherosclerosis. T cell associated cytokines such as $TNF-{\alpha}$ and $IFN-{\gamma}$ have pre-dominant inflammatory effects in chronic vascular diseases. In our previous study, we found that the expression of $TNF-{\alpha}$ and its receptor, $TNF-{\alpha}R$ was increased when Jurkat T lymphocyte cell lines were exposed to TGs. Therefore, experiments were conducted to determine which cell signaling pathway are involved in the increase of $TNF-{\alpha}$ and $TNF-{\alpha}R$ expression by TGs. To identify signal transduction pathways involved in TG-induced upregulation of $TNF-{\alpha}$, we treated TG-exposed Jurkat T cells with specific inhibitors for MEK1, PI3K, $NF-{\kappa}B$ and PKC. We found that inhibition of the MEK1 pathway blocked TG-induced upregulation of $TNF-{\alpha}$. However, the expression level of $TNF-{\alpha}R$ did not change with any signal transduction inhibitor. Based on this observation, we suggest that increase of exogenous TG induces increase of $TNF-{\alpha}$ expression through MEK1 pathway in Jurkat T cells. In addition, it was confirmed that the increase of $TNF-{\alpha}$ and $TNF-{\alpha}R$ expression by TGs occurs via different pathways.

• 셀메드
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• 제2권3호
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• pp.27.1-27.6
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• 2012

Red ginseng, which has a variety of biological and pharmacological activities including antioxidant, anti-inflammatory, antimutagenic and anticarcinogenic effects, has been used for thousands of years as a general tonic in traditional oriental medicine. Here, we tested the immune regulatory activities of hydrolyzed red ginseng by malted barley (HRG) on the expressions of receptor interacting proteins (Rip) 2 and $I{\kappa}B$ kinase-beta (IKK-${\beta}$) in mouse peritoneal macrophages. We show that HRG increased the activations of Rip 2 and IKK-${\beta}$ for the first time. When HRG was used in combination with recombinant interferon-${\gamma}$ (rIFN-${\gamma}$), there was a marked cooperative induction of nitric oxide (NO) production. The increased expression of inducible NO synthase from rIFN-${\gamma}$ plus HRG-stimulated cells was almost completely inhibited by pre-treatment with pyrrolidine dithiocarbamate (PDTC), an inhibitor of nuclear factor-${\kappa}B$ (NF-${\kappa}B$). In addition, the treatment of peritoneal macrophages with rIFN-${\gamma}$ plus HRG caused significant increases in tumor necrosis factor (TNF)-${\alpha}$ mRNA expression and production. Because NO and TNF-${\alpha}$ play an important role in the immune function and host defense, HRG treatment can modulate several aspects of the host defense mechanisms as a result of the stimulations of the inducible nitric oxide synthase and NF-${\kappa}B$. In conclusion, our findings demonstrate that HRG increases the productions of NO and TNF-${\alpha}$ from rIFN-${\gamma}$-primed macrophages and suggest that Rip2/IKK-${\beta}$ plays a critical role in mediating these immune regulatory effects of HRG.

• 대한의생명과학회지
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• 제12권4호
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• pp.329-335
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• 2006

Echinostoma hortense (E. hortense) is an intestinal trematode with the highest infection rate in South Korea. However, the immune response against E. hortense infection has not been explained well. In the present study, we investigated the effect of treatment with cyclosporin A (CsA) and histamine receptor antagonists on the cytokine expression and mucosal goblet cells in E. hortense-infected C3H/HeN mice. The alteration of cytokine mRNA expression ($TNF-{\alpha},\;IL-l{\beta},\;IL-4\;and\;IL-5$), intestinal worm recovery rate and goblet cell responses were measured weekly from 0 to 5 weeks post-infection (P.I.) in the control and the following three drug-treated groups: CsA, hydroxyzine and cimetidine. Compared with the control group, the expression of $TNF-{\alpha}$, IL-4 and IL-5 mRNAs decreased in the CsA- and hydroxyzine-treated groups, but only IL-4 mRNA expression did in the cimetidine-treated group. Worm recovery rate was significantly increased in the drug-treated groups. Mucosal goblet cells and their mucin response significantly decreased in the CsA-treated group (P<0.01), but significantly increased in the cimetidine- (P<0.05) and hydroxyzine- (P<0.01) treated groups. These data suggest that CsA treatment inhibits production of Th1- and Th2-type cytokines which are necessary for the worm expulsion. Histamine receptor increases goblet cells and their mucin activation, although it remains to be elucidated whether it directly affects the worm expulsion period of E. hortense in C3H/HeN mice.

• 한국축산식품학회지
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• 제34권6호
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• pp.829-835
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• 2014

Inflammatory bowel disease (IBD) is caused by dysregulation of colon mucosal immunity and mucosal epithelial barrier function. Recent studies have reported that lipoteichoic acid (LTA) from Lactobacillus plantarum K8 reduces excessive production of pro-inflammatory cytokine. In this study, we investigated the preventive effects of lysate of Lb. plantarum K8 in dextran sulfate sodium (DSS)-induced colitis. Male Sprague-Dawley rats were orally pretreated with lysate of Lb. plantarum K8 (low dose or high dose) or live Lb. plantarum K8 prior to the induction of colitis using 4% DSS. Disease progression was monitored by assessment of disease activity index (DAI). Histological changes of colonic tissues were evaluated by hematoxylin and eosin (HE) staining. Tumor necrosis factor-alpha (TNF-${\alpha}$), interleukin-6 (IL-6) levels were measured using enzyme-linked immunosorbent assay (ELISA). The colon mRNA expressions of TNF-${\alpha}$, IL-6, and toll like receptor-2 (TLR-2) were examined by quantitative real-time-transcription polymerase chain reaction (qPCR). Lysate of Lb. plantarum K8 suppressed colon shortening, edema, mucosal damage, and the loss of DSS-induced crypts. The groups that received lysate of Lb. plantarum K8 exhibited significantly decreased levels of the pro-inflammatory cytokines TNF-${\alpha}$ and IL-6 in the colon. Interestingly, colonic expression of toll like receptor-2 mRNA in the high-dose lysate of Lb. plantarum K8 group increased significantly. Our study demonstrates the protective effects of oral lysate of Lb. plantarum K8 administration on DSS-induced colitis via the modulation of pro-inflammatory mediators of the mucosal immune system.

• Clinical and Experimental Reproductive Medicine
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• 제44권3호
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• pp.146-151
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• 2017

Objective: To identify differences in the expression of the genes for peroxisome proliferator-activated receptor $(PPAR)-{\gamma}$, cyclooxygenase (COX)-2, and the proinflammatory cytokines interleukin (IL)-6 and tumor necrosis factor $(TNF)-{\alpha}$ in granulosa cells (GCs) from polycystic ovary syndrome (PCOS) patients and controls undergoing controlled ovarian stimulation. Methods: Nine patients with PCOS and six controls were enrolled in this study. On the day of oocyte retrieval, GCs were collected from pooled follicular fluid. Total mRNA was extracted from GCs. Reverse transcription was performed and gene expression levels were quantified by realtime quantitative polymerase chain reaction. Results: There were no significant differences in age, body mass index, and total gonadotropin dose, except for the ratio of luteinizing hormone to follicle-stimulating hormone between the PCOS and control groups. $PPAR-{\gamma}$ and COX-2 mRNA was significantly downregulated in the GCs of PCOS women compared with controls (p= 0.034 and p= 0.018, respectively), but the expression of IL-6 and $TNF-{\alpha}$ mRNA did not show significant differences. No significant correlation was detected between the expression of these mRNA sequences and clinical characteristics, including the number of retrieved oocytes, oocyte maturity, cleavage, or the good embryo rate. Positive correlations were found among the $PPAR-{\gamma}$, COX-2, IL-6, and $TNF-{\alpha}$ mRNA levels. Conclusion: Our data may provide novel clues regarding ovarian GC dysfunction in PCOS, and indirectly provide evidence that the effect of $PPAR-{\gamma}$ agonists in PCOS might result from alterations in the ovarian follicular environment. Further studies with a larger sample size are required to confirm these proposals.

• Tuberculosis and Respiratory Diseases
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• 제47권3호
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• pp.304-310
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• 1999

연구배경: 결핵에 대한 면역 반응은 T-림프구와 단핵 식세포를 주축으로 하는 세포성 면역 반응이 주률 이루는데 여기에 IFN-$\gamma$와 TNF-$\alpha$등의 cytokine 이 관여하고 있다. IFN-$\gamma$는 주로 T-림프구에서 분비되어 활성화된 단핵구에서의 TNF-$\alpha$생성을 증가시키는 기전을 통해 결핵균 증식을 억제하고 치유에 이르는 과정을 매개하는 것으로 알려져 있다. 효과적인 화학요법에도 불구하고 난치성 결핵으로 이행하는 기전에 IFN-$\gamma$가 관여하는지 규명하고자 본 연구를 시행하였다. 대상 및 방법: 정상 대조군과 최근 결핵으로 진단받아 치료를 시작한 환자, 난치성 결핵 환자에서 혈액을 채취하여 단핵구를 분리하고 아무런 자극을 하지 않은 경우, 12시간 LPS($l{\mu}g/ml$)만으로 자극을 한 경우, IFN-$\gamma$($2{\mu}g/ml$)로 2시간 전처치한 후 12 시간 LPS 자극한 경우로 니누어 TNF-$\alpha$의 농도를 측정, IFN-$\gamma$ 활성화 효과에 변화가 있는지를 살펴보았고 IFN-$\gamma$ 수용체 항제를 이용, IFN-$\gamma$ 활성화 효과의 변화가 IFN-$\gamma$ 수용체의 숫적 변화와 관련이 있는지를 확인하였다. 결과: IFN-$\gamma$ 활성화 효과를 알아보기 위해 LPS 만으로 지극한 경우와 IFN-$\gamma$ 전처치 후 LPS로 자극한 경우에 생성된 TNF-$\alpha$의 비를 구하여 보았을 때 정상 대조군 $13.5{\pm}7.6$, 최근 결핵환자로 진단받은 군 $10.8{\pm}6.4$, 난치성 결핵 환자군 $6.7{\pm}3.9$의 결과를 보였다. 난치성 결핵환자군의 경우 정상대조군에 비해 IFN-$\gamma$의 활성화 효과가 통계적으로 유의하게 감소되어 있음을 알 수 있었다 (p=0.002). IFN-$\gamma$ 수용체수의 감소는 대상 환자 중 난치성 결핵 환자 1명에서 관찰되었다. 결론: 난치성 결핵으로의 이행에 있어 단핵구에서의 IFN-$\gamma$ 활성화 효과의 감소가 중요한 역할을 할 것으로 생각되며 IFN-$\gamma$ 활성화 효과의 감소는 일부 환자의 경우, IFN-$\gamma$ 수용체의 감소와 관련되어 생기는 것으로 판단된다.

• 생명과학회지
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• 제21권11호
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• pp.1641-1651
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• 2011

TNF ligand 군에 속하는 Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL/Apo2L)은 death receptor를 통한 세포사멸을 유도하는 것으로 알려졌다. TRAIL은 정상세포에서는 세포사를 일으키지 않고 암세포에서만 특이적으로 세포사멸을 유도함으로써 잠재력 있는 항암제로 주목을 받고 있다. 그러나, 최근 연구에 의하면 악성 신장암과 간암과 같은 일부 암에서는 TRAIL에 의한 세포사에 저항성을 가지는 것으로 알려져 있다. 그러므로, TRAIL 만으로는 다양한 악성종양을 위한 치료법으로 적절하지 않다. TRAIL에 대한 저항성을 가지는 분자적 기전을 이해하고, TRAIL 저항성을 극복할 수 있는 증감제를 밝혀내는 것이 보다 효율적인 TRAIL을 이용한 암세포 치료 전략에 필요하다. 화학치료제들이 TRAIL 수용체인 death receptor의 발현을 증가시키고, 세포 내의 TRAIL에 의한 신호전달 체계를 활성화 시키는 것으로 알려져 있고, 이러한 기전을 통하여 다양한 화학치료제들이 TRAIL에 의한 세포사멸을 증가시키는 것을 확인하였다. 이 논문에서, 우리는 TRAIL에 의한 세포 사멸을 증가시키기 위한 생물학적 약물을 정리하고, 그 분자적 기전을 고찰한다.

• Asian-Australasian Journal of Animal Sciences
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• 제25권9호
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• pp.1316-1321
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• 2012

Adipokines, adipocyte-derived protein, have important roles in various kinds of physiology including energy homeostasis. Chemerin, one of adipocyte-derived adipokines, is highly expressed in differentiated adipocytes and is known to induce macrophage chemotaxis and glucose intolerance. The objective of the present study was to investigate the changes of chemerin and the chemokine-like-receptor 1 (CMKLR1) gene expression levels during differentiation of the bovine adipocyte and in differentiated adipocytes treated with tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), adiponectin, leptin, and chemerin (peptide analog). The expression levels of the chemerin gene increased at d 6 and 12 of the differentiation period accompanied by increased cytoplasm lipid droplets. From d 6 onward, peroxisome proliferator-activated receptor-${\gamma}2$ (PPAR-${\gamma}2$) gene expression levels were significantly higher than that of d 0 and 3. In contrast, CMKLR1 expression levels decreased at the end of the differentiation period. In fully differentiated adipocytes (i.e. at d 12), the treatment of TNF-${\alpha}$ and adiponectin upregulated both chemerin and CMKLR1 gene expression levels, although leptin did not show such effects. Moreover, chemerin analog treatment was shown to upregulate chemerin gene expression levels regardless of doses. These results suggest that the expression of chemerin in bovine adipocyte might be regulated by chemerin itself and other adipokines, which indicates its possible role in modulating the adipokine secretions in adipose tissues.