• 약학회지
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• 제41권5호
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• pp.629-637
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• 1997

Tumor necrosis factor-${alpha}$ (TNF) induced a cytotoxic response in ME-180 cervical carcinoma cells in vitro. This cytotoxic response was accompanied by a temporal series of mitogenic stimuli : increased c-fos, c-jun and jun-B expression. Depletion of protein kinase C (PKC) by exposure of ME-180 cells to 100ng/ml phorbol myristate acetate (PMA) for 24hours almost completely abolished TNF-mediated increase in these signals, indicating that a PKC-dependent pathway is involved in TNF-mediated increases in the expression of c-fos, c-jun and jun-B. Characteristics of TNF receptors after exposure to 100ng/ml PMA or 24hours were not altered, suggesting that diminished induction of these oncogenes by TNF after PMA treatment is not due to any changes at the receptor level. To examine whether a PKC-dependent pathway is involved in TNF-mediated cytotoxicity in ME-180 cells, cytotoxicity was measured after depletion of PKC. No apparent changes in cytototoxicity after PKC depletion suggest that a PKC-dependent pathway is not involved in TNF-mediated cytotoxicity. Furthermore, results from cytotoxicity tests after exposure to staurosporine (PKC inhibitor) did not show any changes in the TNF-mediated cytotoxicity, confirming that a PKC-dependent pathway is not involved in this process. These data indicate that 1) TNF induces expression of c-fos, c-jun and jun-B oncogenes via a PKC-dependent pathway and 2) PKC-dependent expression of these three oncogenes by TNF may not be involved in TNF-mediated cytotoxicity in ME-180 cells.

• Journal of Chest Surgery
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• 제36권9호
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• pp.666-673
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• 2003

폐암의 주된 원인으로 알려진 흡연은 그 악성세포 발현기전이 아직 정확히 규명된 바 없다. 이에 저자들은 흡연에 의한 발암성의 지표로 흡연 중에 특이적으로 존재하는 강력한 발암물질인 NNK(4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone)를 이용하여 흡연에 따른 폐암의 발생과 그 Protein kinase C (PKC) isoform과 관련된 기전에 관한 연구를 시도하였다. 대상 및 방법: 인체 상피세포를 NNK에 노출시킨 후 saturation density, soft agar colony formation, cell aggregation 및 foci의 출현 등의 양상을 파악하여 세포 발암성 여부를 관찰하였으며 NNK를 15분간 노출시킨 후 PKC의 변화는 세포 내 PKC isoform의 양을 cytosolic fraction과 membrane fraction으로 분리하여 측정하여 분석하였다. 결과: NNK 투여군에서 saturation density, soft agar colony formation, cell aggregation 및 foci의 출현 시기 등의 세포 발암성을 뚜렷이 나타내었으며 PKC isoform분석의 경우 PKC-$\alpha$의 membrane fraction의 뚜렷한 증가를 보였으며 이러한 활성은 용량-의존적인 형태를 유지하였다. PKC-$\varepsilon$은 NNK 처리 시 용량-의존적으로 cytosol fraction의 감소 및 membrane fraction의 증가를 뚜렷하게 보였고 NNK에 의한 PKC-λ의 변화는 감지되지 않았다. 결론: 본 연구는 화학적 발암물질인 NNK가 인체발암화에 관여함을 재차 확인하면서 초기 과정에 관여하는 PKC isoform의 변화를 분석함으로써 total PKC활성이 아닌 isoform 각각에 대한 변화를 확인하였다는 점에서 앞으로 인체상피세포 기원의 폐암 생성 기전 연구에 기여할 것으로 생각한다.

• The Journal of Korean Physical Therapy
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• 제20권3호
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• pp.61-68
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• 2008

Purpose: Protein kinase C (PKC) is a member of a family of serine/threonine kinases that are activated by diacylglycerol (DG) and PKC stimulants. PKC play a key role in signal transduction, including muscle contraction, cell migration, apoptosis, cell proliferation and differentiation. However, the mechanism relating mitogen-activated protein kinases (MAPKs) and PKC, especially in the volume-dependent hypertensive state, remains unclear. Methods: In the present study, I investigated the relationship between PKC and MAPKs for isometric contraction, PKC translocation, and enzymatic activity from normotensive sham-operated rats (NSR) and aldosterone-analogue deoxycorticosterone acetate (DOCA) hypertensive rats (ADHR). Results: Systolic blood pressure was significantly increased in ADHR than in NSR. Physiological salt solution (PSS)-induced resting tension and the intracellular $Ca^{2+}$ concentration ([$Ca^{2+}{_i}$]) were different in the ADHR and NSR. The expression of PKC$\alpha$, PKC$\beta$II, PKC$\delta$, PKC$\varepsilon$ and PKC$\xi$ were different between the cytoplasmic and membranous fractions. However, expression of the PKC isoforms did not differ for the ADHR and NSR. The use of 12-deoxyphorbol 13-isobutyrate (DPB, a PKC stimulant) induced isometric contraction in $Ca^{2+}$-free medium, which was diminished in muscle strips from ADHR as compared to NSR. Increased vasoconstriction and phosphorylation induced by the use of 1 ${\mu}$M DPB were inhibited by treatment with 10 ${\mu}$M PD098059 and 10 ${\mu}$M SB203580, inhibitors of extracellular-regulated protein kinase 1/2 (ERK1/2) and p38 MAPK from ADHR, respectively. Conclusion: These results suggest that the development of aldosterone analogue-induced hypertension is associated with an altered blood pressure, resting tension, [$Ca^{2+}{_i}$], and that the $Ca^{2+}$-independent contraction evoked by PKC stimulants is due to the activation of ERK1/2 and p38 MAPK in volume-dependent hypertension. Therefore, it is suggested that PKC activity affects volume-dependent hypertension and the need to develop cardiovascular disease-specialized physical therapy.

• Asian-Australasian Journal of Animal Sciences
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• 제21권7호
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• pp.1053-1058
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• 2008

A total of 392 twenty eight week-old laying hens was used to study the effects of dietary inclusion of solvent-extracted palm kernel cake (PKC) (0%, 12.5% and 25%) and enzyme (mixture of mannanase, ${\alpha}$-galactosidase and protease) supplementation (0 kg/t, 1 kg/t and 2 kg/t) on the performance of laying hens. The levels of PKC did not significantly influence nitrogen corrected true metabolizable energy (TMEn) of the diets. Enzyme-supplemented PKC had significantly higher AME and TMEn values than PKC diets with no enzyme supplementation. Dietary inclusion of 12.5% and 25% PKC in the diets of laying hens did not adversely affect mean egg production or daily egg mass. However, layers consumed significantly more PKC-based diets and had significantly poorer feed conversion ratios (FCR) than controls. However, the feed intake and FCR of hens provided the 12.5% PKC-based diets with enzyme supplementation at 1 kg/t did not differ from the controls. Dietary inclusion of PKC or enzyme did not affect eggshell quality, but egg yolk colour was significantly paler when layers were fed the 25% PKC diet.

• Genomics & Informatics
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• 제6권1호
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• pp.44-49
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• 2008

Protein kinase C (PKC) is a family of kinases involved in the transduction of cellular signals that promote lipid hydrolysis. PKC plays a pivotal role in mediating cellular responses to extracellular stimuli involved in proliferation, differentiation and apoptosis. Comparative analysis of the PKC-${\alpha},{\beta},{\varepsilon}$ isozymes of 200 recently sequenced microbial genomes was carried out using variety of bioinformatics tools. Diversity and evolution of PKC was determined by sequence alignment. The ser/thr protein kinases of Streptomyces coelicolor A3 (2), is the only bacteria to show sequence alignment score greater than 30% with all the three PKC isotypes in the sequence alignment. S.coelicolor is the subject of our interest because it is notable for the production of pharmaceutically useful compounds including anti-tumor agents, immunosupressants and over two-thirds of all natural antibiotics currently available. The comparative analysis of three human isotypes of PKC and Serine/threonine protein kinase of S.coelicolor was carried out and possible mechanism of action of PKC was derived. Our analysis indicates that Serine/ threonine protein kinase from S. coelicolor can be a good candidate for potent anti-tumor agent. The presence of three representative isotypes of the PKC super family in this organism helps us to understand the mechanism of PKC from evolutionary perspective.

• 대한수의학회지
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• 제39권6호
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• pp.1073-1080
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• 1999

Previous studies suggested that the inhibition of thyroxine ($T_4$) release by ${\alpha}_1$-adrenoceptor and muscarinic receptor stimulation results in activated protein kinase C (PKC) from mouse and guinea pig thyroids. In the present study, the effect of carbachol, methoxamine, phorbol myristate acetate (PMA), and R59022 on the release of $T_4$ from the mouse, rat, and guinea pig thyroids was compared to clarify the role of PKC in the regulation of the release of $T_4$. The thyroids were incubated in the medium containing the test agents, samples of the medium were assayed for $T_4$ by EIA kits. Forskolin, an adenylate cyclase activator, chlorophenylthio-cAMP sodium, a membrane permeable analog of cAMP, and isobutyl-methylxanthine, a phosphodiesterase inhibitor, like TSH (thyroid stimulating hormone), enhaced the release of $T_4$ from the mouse, rat, and guinea pig thyroids. Methoxamine, an ${\alpha}_1$-adrenoceptor agonist, inhibited the TSH-stimulated release of $T_4$ in mouse, but not rat and guinea pig thyroids. In contrast, carbachol, a muscarinic receptor agonist, inhibited the release of $T_4$ in guinea pig, but not mouse and rat thyroids. These inhibition were reversed by prazosin, an ${\alpha}_1$-adrenoceptor antagonist or atropine, a muscarinic antagonist or $M_1$- and $M_3$-muscarinic antagonists, in mouse or guinea pig thyroids. In addition, staurosporine, a PKC inhibitor, reversed methoxamine or carbachol inhibition of TSH stimulation. Furthermore, PMA, a PKC activator, and R59022, a diacylglycerol (DAG) kinase inhibitor, inhibited the TSH-stimulated release of $T_4$ in mouse, rat, and guinea pig thyroids. These inhibition were blocked by staurosporine. These findings suggest that the activation of receptor or DAG inhibits TSH-stimulated $T_4$ release through a PKC-dependent mechanism in thyroid gland.

• 대한의생명과학회지
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• 제16권2호
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• pp.119-122
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• 2010

Interleukin-1${\beta}$ $(IL-1{\beta})$ is one of the key proinflammatory cytokines and it plays an important role for the antimycobacterial host defense mechanisms. In this study, we examined Mycobacterium tuberculosis (MTB)-stimulated induction of IL-1${\beta}$ and evaluated the associated signal transduction pathways. In PMA-differentiated THP-1 cells, MTB infection increased mRNA expression of IL-$1{\beta}$ in a dose-dependent manner. The expression of IL-1${\beta}$ mRNA began to be induced at 1.5 h after infection, and induced expression of IL-1${\beta}$ was retained for 48 h after MTB infection. The increase in expression of IL-1${\beta}$ caused by MTB was reduced in cells treated with Ro-31-8425 (an inhibitor of PK$C{\alpha}$, ${\beta}I$, ${\beta}II$, ${\gamma}$, ${\varepsilon}$) or PD98059 (an inhibitor of MEK1), meanwhile, pre-treatment with $G\ddot{o}6976$ (an inhibitor of $Ca^{2+}$ dependent PK$C{\alpha}$ and PK$C{\beta}I$) or Rottlerin (an inhibitor of PK$C{\delta}$) has no effect on MTB-induced expression of $IL-1{\beta}$ mRNA. These results show that the expression of $IL-1{\beta}$ mRNA caused by MTB may be mediated via MEK1 and PKC isoforms including PK$C{\beta}II$, $PKC{\gamma}$, or $PKC{\varepsilon}$. Further studies are required to determine whether other PKC isoforms $(PKC {\eta},\;{\theta},\;{\varepsilon},\;and\;{\lambda}/{\iota})$, except $PKC{\delta}$, $PKC{\alpha}$, and $PKC{\beta}I$, are also involved in $IL-1{\beta}$ mRNA expression after mycobacterial infection.

• 한국동물학회지
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• 제39권3호
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• pp.266-272
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• 1996

봄에 채집한 참개구리의 난소조각 배양계를 사용하여 난자의 배란과정에 프로스타글란딘과 protein kinase C(PKC)가 관여하는 지를 조사하였다. 난소조각을 배양하면서 뇌하수체추출물(FPH) 혹은PKC의 활성제인 12-O-tetradecanoyl phorbol-13-acetate (TPA)를 처리한 후 배란율과 프로스타글란딘의 생상량을 방사면역측정법으로 조사한 결과 농도에 의존하여 난자의 배란이 유도 되었으며 프로스타글란딘의 생성이 촉진되었다. FPH와 TPA에 의한 배란과 프로스타글란딘 생성은, 4월 보다는 5월에 채집한 개구리에서 훨씬 더 효과적이었다. FPH처리는 프로스타글란딘과 함께 progestreone의 생성을 촉진하였으나 TPA는 progestreone의 생성을 촉진하지는 못하였다. FPH와 TPA에 의한 배란과ㅣ 프로스타글라딘 생성 억제제인 indomethacin에 의해서는 난자의 배랑니 억제되지는 않았다. 이러한 결과들은 참개구리 난자의 배란 과정에 PKC의 활성화가 중요한 역할을 하며, 프로스타글라딘의 생성이 매개할 것으로 생각된다.

• BMB Reports
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• 제31권4호
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• pp.350-354
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• 1998

To understand the role of protein kinase C (PKC) in the regulation of chondrogenesis, we examined proteins which are phosphorylated by PKC. Stage 23/24 chick embryo wing mesenchymes were micromass-cultured to induce chondrogenesis and cell extracts were phosphorylated in a condition that activates PKC. Several proteins including 63 and 66 kDa proteins were phosphorylated. The 66 kDa protein was phosphorylated only in the presence of phorbol 12-myristate 13-acetate (PMA) and phosphatidylserine CPS), and the phosphorylation was almost completely diminished by bisindolylmaleimide, a PKC inhibitor. In addition, partially purified PKC increased the phosphorylation of the 66 kDa protein. Treatment of cultures with lysophosphatidylcholine (LPC) promoted chondrogenesis and phosphorylation of 66 kDa protein, while PMA and thymeleatoxin inhibited both of the two events. Our results suggest that the 66 kDa protein is a putative substrate of PKC, and phosphorylation of the 66 kDa protein, probably by $PKC\alpha$ is required for chondrogenesis.

• Archives of Pharmacal Research
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• 제21권4호
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• pp.452-457
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• 1998

Three compounds, 5-(acetoxymethyl)-5-(hydroxymethyl)-3-tetradecyl-2,5-dihydro-2-furanone (3), 5-(acetoxymethyl)-5-(hydroxymethyl)-3,3-dihexyltetrahydro-2-furanone (4) and 5-(acetoxymethyl)-5-(hydroxymethyl)-3,3-dioctyltetrahydro-2-furanone (5), were designed and synthesized as surrogates of the ultrapotent DAG analogue, 5-(acetoxymethyl)-5-(hydroxymethyl) 3-[(Z)-tetradecylideneltetrahydro-2-furanone (1), a compound that showed high affinity for PKC-$\alpha$ ($K_1$=35 nM) in a competition binding assay with [$^3H$-20]phorbol-12,13-dibutyrate (PDBU). In an attempt to overcome the problem of generating geometrical E- and Z- isomers, as encountered with 1, the double bond was moved to an endocyclic location as in 3, or an additional alkyl chain was appended to C3 to give the corresponding 3,3-dialkyl saturated lactones (4 and 5). The lactone was constructed from glycidyl-4-methoxyphenyl ether in 5 steps. The target compounds showed reduced binding affinities for PKC-.alpha. with $K_{i}$ values of 192 nM (3), 4,829 nM (4), and 2,812 nM (5), respectively. These results indicate that constrained DAG analogues having a tetrahydro-2-furanone template are effectively discriminated by PKC-(X in terms of the direction of the long alkyl chain connected to the 3-position.n.