• 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.

• Natural Product Sciences
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• 제3권1호
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• pp.29-37
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• 1997

Protein Kinase C (PKC) is generally believed to play a central role in signal transduction, cellular growth control, gene expression, and tumor promotion. And it has been suggested that inhibitors of PKC might play important roles for the prevention and treatment of cancer. In order to investigate the possible inhibitors of PKC from natural products, PKC receptor binding assay was performed using bovine brain particulate as a source of PKC and the amount of $[^3H]Phorbol$ 12,13-dibutyrate (PDBu) bound to PKC was measured in the presence of test materials. Total methanol extracts from 100 kinds of natural products were partitioned into 3 fractions (n-hexane, ethyl acetate and aqueous layer) and their binding ability to the regulatory domain of PKC was evaluated. The ethyl acetate fractions of Morus alba $(roots,\;IC_{50}:\;156.6\;{\mu}g/ml)$, Rehmannia glutinosa $(roots,\;IC_{50}:\;134.3\;{\mu}g/ml)$, Lysimachia foenum-graecum $(roots,\;IC_{50}:\;167.8\;{\mu}g/ml)$, Polygonum cuspidata $(roots,\;IC_{50}:\;157.3\;{\mu}g/ml)$, Cnidium officinale $(aerial\;parts,\;IC_{50}:\;145.2\;{\mu}g/ml)$, and the hexane $(IC_{50}:\;179.3\;{\mu}g/ml)$ and the EtOAc fraction of Symplocarpus nipponicus $(roots,\;IC_{50}:\;155.9\;{\mu}g/ml)$ showed inhibitory activity of $[^3H]PDBu$ binding to PKC.

• Molecules and Cells
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• 제39권3호
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• pp.266-279
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• 2016

The mechanism by which 12-O-tetradecanoylphorbol-13-acetate (TPA) bypasses cellular senescence was investigated using human diploid fibroblast (HDF) cell replicative senescence as a model. Upon TPA treatment, protein kinase C (PKC) ${\alpha}$ and $PKC{\beta}1$ exerted differential effects on the nuclear translocation of cytoplasmic pErk1/2, a protein which maintains senescence. $PKC{\alpha}$ accompanied pErk1/2 to the nucleus after freeing it from $PEA-15pS^{104}$ via $PKC{\beta}1$ and then was rapidly ubiquitinated and degraded within the nucleus. Mitogen-activated protein kinase docking motif and kinase activity of $PKC{\alpha}$ were both required for pErk1/2 transport to the nucleus. Repetitive exposure of mouse skin to TPA downregulated $PKC{\alpha}$ expression and increased epidermal and hair follicle cell proliferation. Thus, $PKC{\alpha}$ downregulation is accompanied by in vivo cell proliferation, as evidenced in 7, 12-dimethylbenz(a)anthracene (DMBA)-TPA-mediated carcinogenesis. The ability of TPA to reverse senescence was further demonstrated in old HDF cells using RNA-sequencing analyses in which TPA-induced nuclear $PKC{\alpha}$ degradation freed nuclear pErk1/2 to induce cell proliferation and facilitated the recovery of mitochondrial energy metabolism. Our data indicate that TPA-induced senescence reversal and carcinogenesis promotion share the same molecular pathway. Loss of $PKC{\alpha}$ expression following TPA treatment reduces pErk1/2-activated SP1 biding to the $p21^{WAF1}$ gene promoter, thus preventing senescence onset and overcoming G1/S cell cycle arrest in senescent cells.

• The Korean Journal of Physiology and Pharmacology
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• 제18권4호
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• pp.289-296
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• 2014

Human adipose-tissue-derived stromal cells (hADSCs) are abundant in adipose tissue and can differentiate into multi-lineage cell types, including adipocytes, osteoblasts, and chondrocytes. In order to define the optimal harvest site of adipose tissue harvest site, we solated hADSCs from different subcutaneous sites (upper abdomen, lower abdomen, and thigh) and compared their proliferation and potential to differentiate into adipocytes and osteoblasts. In addition, this study examined the effect of phorbol 12-myristate 13-acetate (PMA), a protein kinase C (PKC) activator, on proliferation and differentiation of hADSCs to adipocytes or osteoblasts. hADSCs isolated from different subcutaneous depots have a similar growth rate. Fluorescence-activated cell sorting (FACS) analysis showed that the expression levels of CD73 and CD90 were similar between hADSCs from abdomen and thigh regions. However, the expression of CD105 was lower in hADSCs from the thigh than in those from the abdomen. Although the adipogenic differentiation potential of hADSCs from both tissue regions was similar, the osteogenic differentiation potential of hADSCs from the thigh was greater than that of hADSCs from the abdomen. Phorbol 12-myristate 13-acetate (PMA) treatment increased osteogenic differentiation and suppressed adipogenic differentiation of all hADSCs without affecting their growth rate and the treatment of Go6983, a general inhibitor of protein kinase C (PKC) blocked the PMA effect. These findings indicate that the thigh region might be a suitable source of hADSCs for bone regeneration and that the PKC signaling pathway may be involved in the adipogenic and osteogenic differentiation of hADSCs.

• Journal of Microbiology and Biotechnology
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• 제14권5호
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• pp.919-923
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• 2004

The sk10 isolated from kimchi was identified as W. kimchii on the basis of l6s-rDNA sequencing. Studies were made to analyze the metabolic flux shift of the sk10 on glucose under aerobic growth conditions. The sk10 produced 38.2 mM acetate, 16.3 mM ethanol, and 33.2 mM lactate under aerobic conditions, but 2.4 mM acetate, 48.0 mM ethanol, and 44.1 mM lactate under anaerobic conditions. The NADH peroxidase (NADH-dependent hydrogen peroxidase) activity of sk10 grown under aerobic conditions was 11 times higher than that under anaerobic conditions. Under the low ratio of $NADH/NAD^+$, the metabolic flux toward lactate and ethanol was shifted to the flux through acetate kinase without NADH oxidation. The kinds of enzymes and metabolites of sk10 were close to those in the pathway of Leuconostoc sp., but the metabolites produced under aerobic growth conditions were different from those of Leuconostoc sp. The stoichiometric balance calculated using the concentrations of metabolites and substrate was about 97%, coincident with the theoretical values under both aerobic and anaerobic conditions. From these results, it was concluded that the metabolic flux of W. kimchii sk10 was partially shifted from lactate and ethanol to acetate under aerobic conditions only.

• BMB Reports
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• 제55권2호
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• pp.87-91
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• 2022

Aurora kinase is a family of serine/threonine kinases intimately associated with mitotic progression and the development of human cancers. Studies have shown that aurora kinases are important for the protein kinase C (PKC)-induced invasion of colon cancer cells. Recent studies have shown that aurora kinase A promotes distant metastasis by inducing epithelial-to-mesenchymal transition (EMT) in colon cancer cells. However, the role of aurora kinase A in colon cancer metastasis remains unclear. In this study, we investigated the effects of aurora kinase A on PKC-induced cell invasion, migration, and EMT in human SW480 colon cancer cells. Treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA) changed the expression levels of EMT markers, increasing α-SMA, vimentin, and MMP-9 expression and decreasing E-cadherin expression, with changes in cell morphology. TPA treatment induced EMT in a PKC-dependent manner. Moreover, the inhibition of aurora kinase A by siRNAs and inhibitors (reversine and VX-680) suppressed TPA-induced cell invasion, migration, and EMT in SW480 human colon cells. Inhibition of aurora kinase A blocked TPA-induced vimentin and MMP-9 expression, and decreased E-cadherin expression. Furthermore, the knockdown of aurora kinase A decreased the transcriptional activity of NF-κB and AP-1 in PKC-stimulated SW480 cells. These findings indicate that aurora kinase A induces migration and invasion by inducing EMT in SW480 colon cancer cells. To the best of our knowledge, this is the first study that showed aurora kinase A is a key molecule in PKC-induced metastasis in colon cancer cells.

• Biomolecules & Therapeutics
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• 제21권6호
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• pp.435-441
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• 2013

Emodin, a naturally occurring anthraquinone derivative isolated from Polygoni cuspidati radix, has several beneficial pharmacologic effects, which include anti-cancer, anti-diabetic, and anti-inflammatory activities. In this study, the authors examined the effect of emodin on the production of proinflammatory cytokines, such as, tumor necrosis factor (TNF)-${\alpha}$ and interleukin (IL)-6, in mouse bone marrow-derived mast cells (BMMCs) stimulated with phorbol 12-myristate 13-acetate (PMA) plus the calcium ionophore A23187. To investigate the mechanism responsible for the regulation of pro-inflammatory cytokine production by emodin, the authors assessed its effects on the activations of transcriptional factor nuclear factor-${\kappa}B$ (NF-${\kappa}B$) and mitogen-activated protein kinases (MAPKs). Emodin attenuated the nuclear translocation of (NF)-${\kappa}B$ p65 and its DNA-binding activity by reducing the phosphorylation and degradation of $I{\kappa}B{\alpha}$ and the phosphorylation of $I{\kappa}B$ kinase B (IKK). Furthermore, emodin dose-dependently attenuated the phosphorylations of MAPKs, such as, extracellular signal-regulated kinase 1/2 (ERK1/2), p38 MAP kinase, and the stress-activated protein kinases (SAPK)/c-Jun-N-terminal kinase (JNK). Taken together, the findings of this study suggest that the anti-inflammatory effects of emodin on PMA plus A23187-stimulated BMMCs are mediated via the inhibition of NF-${\kappa}B$ activation and of the MAPK pathway.

• 대한물리치료과학회지
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• 제13권2호
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• pp.137-145
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• 2006

We investigated whether increased contractile responsiveness to epidermal growth factor (EGF) is associated with altered activation of mitogen-activated protein kinase (MAPK) in the aortic smooth muscle of deoxycorticosterone acetate (DOCA)-salt hypertensive rats. EGF induced contraction and MAPK activity in aortic smooth muscle strips, which were significantly increased in tissues from the DOCA-salt hypertensive rats compared with those from sham-operated rats. AG1478, PD98059, and LY294002, inhibitors of EGF receptor (EGFR) tyrosine kinase, MAPK/extracellular signal-regulated kinase (ERK) kinase, and phosphatidylinositol 3-kinase (PI3K), respectively, inhibited the contraction and the activity of ERK1/2 that were elevated by EGF. Y27632 and GF109203X, inhibitors of Rho kinase and protein kinase C, respectively, attenuated EGF-induced contraction, with no diminution of ERK1/2 activity. Although EGF also elevated the activity of EGFR tyrosine kinase in both sham-operated and DOCA-salt hypertensive rats, the expression and the magnitude of activation did not differ between strips. These results strongly suggest that EGF induces contraction by the activation of ERK1/2, which is regulated by the PI3K pathway in the aortic smooth muscle of DOCA-salt hypertensive rats.

• Applied Microscopy
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• 제33권4호
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• pp.299-313
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• 2003

본 연구는 피부화상으로 유도된 심근손상에서 protein kinase C (PKC)의 역할을 알아보고자 하였다. 수컷 흰 쥐(SD계)에 15%의 피부전층화상을 유도한 뒤, PKC activator인 phorbol 12-myristate 13-acetate (PMA)와 PKC inhibitor인 bisindolylmaleimide (BIS)를 투여하여 5시간, 24시간 후에 심장을 적출하여 생화학적 미세구조적 입체해석학적 방법을 실시하였다. 혈청 AST와 creatinine 은 화상 후 5시간군과 화상 후 5시간+BIS 투여군에서 높게 나타났고, KC와 MPO 활성은 PMA 투여군이 BIS 투여군보다 낮게 나타났다. 미세구조적 관찰 결과 PMA 투여군에서는, 화상으로 인한 핵의 분열, 과수축대 형성, 사이원반의 분리 현상이 다소 완화된 형태로 관찰되었고, BIS 투여군에서는 화상 단독군에서 나타나는 형태적 변화 뿐만 아니라 비정상적인 형태의 사립체도 일부 관찰되었다. 전체적으로 5시간에서 24시간군으로 가면서 손상이 완화된 양상을 나타내었다. 입체해석학적 결과에서는 화상으로 인한 근원섬유의 체적밀도 감소가 PMA와 BIS 투여로 인해 증가되었고, 사립체의 체적밀도와 수밀도의 증가는 BIS군에서 가장 높게 나타났다. 결론적으로 PKC의 활성화는 화상으로 인해 손상된 심근에서 염증반응을 감소시켜 심근 손상을 보호한다고 사료된다.

• 생명과학회지
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• 제13권4호
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• pp.441-447
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• 2003

Protein kinase C (PKC)가 interleukin-1 beta (IL-1$\beta$)에 의하여 산화질소(NO) 생성과정에 어떤 역할을 하는지를 검토하기 위하여, 혈관평활근세포에서 PKC 활성제인 phorbol 12-myristate 13-acetate (PMA)로 전처리한 후 IL-1$\beta$에 의하여 야기되는 NO생성을 nitrite ($NO_2$)로 정량하고, RT-PCR method를 이용하여 iNOS 발현에 미치는 영향을 검토하여 다음과 같은 결과를 얻었다. PMA (20, 200 nM)는 IL-1$\beta$에 의한$NO_2$ 생성을 유의하게 증가시켰다. PMA 200 nM, phorbol 12,13-dibutyrate 500 nM로 전처리하여 8, 24시간 노출된 세포에서 IL-1$\beta$에 의한 NO2생성이 현저히 감소되었으나, PKC 비활성제인 4$\alpha$-phorbol-didecanoate 200 nM로 전처리한 경우는 영향을 받지 아니하였다. PMA 농도를 달리하여 24시간 전처리한 경우 IL-1$\beta$에 의한 $NO_2$ 생성의 감소는 PMA의 농도가 20및 200 nM에서 현저하였다. RT-PCR method를 이용하여 iNOS 발현을 검토한바 IL-1$\beta$ 100U/ml에 의한 iNOS발현이 PMA전처리 및 cycloheximide 또는 actinomycin D존재로서 현저히 억제 되었다. 이상의 결과로 미루어 혈관평활근세포에서 PMA 전처리로 야기되는 IL-1$\beta$에 의한 NO 생성의 감소는, PKC 조절저하작용에 의한 iNOS 발현의 억제로 야기되는 것 같다.