• 생명과학회지
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• 제24권12호
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• pp.1378-1382
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• 2014

Phospholipase D (PLD)는 세포막을 구성하는 주요지질인 인지질을 분해하여, 이차신호전달물질인 phosphatidic acid (PA)를 생성함으로써 세포의 성장 및 증식, 생존신호전달등 세포내 다양한 생리현상을 조절하는 중요한 신호전달 핵심단백질로 대두되고 있다. PLD의 비정상적인 발현과 활성은 다양한 암을 비롯한 여러 질환에서 나타난다. PLD에 의해 생성된 PA는 세포사멸 유전자의 발현을 감소시켜서 세포사멸에 대한 내성을 나타내고 있다.최근에, 세포사멸과정에서 PLD 단백질의 turnover dynamics에 관한 분자수준에서의 연구가 규명되었다. PLD는, 세포사멸시 활성화되는 단백질 분해효소인 caspases의 새로운 기질로 작용하여 세포사멸을 차별적으로 조절을 한다. Caspase에 의한 PLD동위효소의 차별적인 분해양상이 PLD의 효소활성과 세포사멸억제 기능을 조절한다. 그래서 PLD는 암치료의 표적분자로서의 가능성이 제시된다. 본 리뷰논문에서, 세포사멸조절 PLD의 기능적 역할에 대해 서술하고자 한다.

• Childhood Kidney Diseases
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• 제24권1호
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• pp.36-41
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• 2020

Purpose: Hepatitis B virus (HBV) infection is among etiologies of secondary membranous nephropathy (MN) in pediatric patients. We evaluated expression of phospholipase A2 receptor (PLA2R), a specific target antigen of primary MN, in pediatric HBV-related MN. Methods: We retrospectively reviewed patients with biopsy-proven HBV-related MN from the renal biopsy registry and electronic medical records of Severance Hospital, Seoul, Korea, from 1993 to 2004. Paraffin-embedded human kidney tissues were retrieved and immunohistochemically stained for PLA2R. Results: Ten pediatric patients with 13 biopsied specimens were reviewed. The predominant pathological stage was stage II-III, and second was stage II. The intensity of staining for IgG was greatest, with less intense staining for IgM, IgA, C3, C4, and C1q. All the patients had angiotensin-converting enzyme inhibitor combined with glucocorticoid, and four patients converted to cyclosporine treatment from glucocorticoid monotherapy. Urinalysis of all the patients normalized after variable period. PLA2R staining was demonstrated in the outer glomerulus in 3 out of 13 biopsies, 2 of which were obtained from the same patient over a 5-year interval. Conclusions: PLA2R was expressed in a small number of cases diagnosed as pediatric HBV-related MN, indicating that some HBV-related MN cases may be primary MN concurrent with HBV infection.

• Journal of Acupuncture Research
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• 제17권4호
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• pp.69-78
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• 2000

Objective : To research the trends of the study related to bee venom and cancer, and to establish the hereafter direction of the study on bee venom herbal acupuncture. Method : We searched in PubMed, with bee venom and cancer(in English, with abstract) Results : 1. We searched 28 Journals, 36 Papers. the frequency of Journals and Papers was as follows: Biochem Biophys Res Commun(4 Papers), FEBS Lett(3), Life Sci, Proc Natl Acad Sci USA, J Immunol(each 2), other 23 Journals(each 1). 2. The pattern of the study was as follows: Review article(3 Journals, 3 Papers), Epidemiologic study(1, 1), Experimental study(24, 32) In vivo 1, 1), In vitto(24, 31) 3. The involved components of bee venom were as follows: Melittin(20), Apamin(8), Phospholipase A2(3), Melittin & Phospholipase A2(3), Melittin& Tertiapin(1). 4. The involved cancer was as follows: leukemia(9), tumor(5), neuroblastoma(4), pituitary tumor and pheochromocytoma(each 3), lymphoma, astrocytoma, glioma and lung cancer(small cell carcinoma)(eacn 2), bladder carcinoma, pancreatic cancer, breast carcinoma, ovarian carcinoma and spuamous cell carcinoma(each 1) Conclusion : We concluded that the most frequent pattern of the study was in vitro experimental study with peptide components of bee venom and the most frequeni invovled cancer was leukemia.

• Journal of Microbiology and Biotechnology
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• 제12권2호
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• pp.189-195
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• 2002

Using Streptomyces sp. YU100 isolated from Korean soil, the fermentative production of phospholipase D was attempted along with its purification and characterization studies. When different carbon and nitrogen sources were supplemented in the culture medium, glucose and yeast extract were found to be the best. By varying the concentration of nutrients and calcium carbonate, the optimal culture medium was determined as 2.0% glucose, 1.5% yeast extract, 0.5% tryptone 0.3% calcium carbonate. During cultivation, the strain secreted most of the phospholipase D in the early stage of growth within 24 h. The phospholipase D produced in the culture broth exhibited hydrolytic activity as well as transphosphatidylation activity on lecithin (phosphatidylcholine). In particular, the culture broth showed 8.7 units/ml of hydrolytic activity when cultivated at $28^{\circ}C$ for 1.5 days. The phospholipase D was purified using 80% ammonium sulfate precipitation and DEAE-Sepharose CL-6B column chromatography, which produced a major band of 57 kDa on a 10% SDS-polyacrylamide gel with purity higher than 80%. The enzyme showed an optimal pH of 7 in hydrolytic reaction, and at pH 4 in a transphosphatidylation reaction. The enzyme activity increased until the reaction temperature was elevated to $60^{\circ}C$. The enzyme was relatively stable at high temperatures and neutral pH, but significantly unstable in the alkaline range. Among the detergents tested as emulsifiers of phospholipids, the highest enzyme activity was observed when 1.5% Triton X-100 was employed. However, no inhibitory effect by metal ions was detected. Under optimized reaction conditions, the purified enzyme not only completely decomposed PC to phosphatidic acid within 1 h, but also exhibited higher than 80% conversion rate of PC to PS by transphosphatidylation within 4 h.

• 한국미생물·생명공학회지
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• 제24권1호
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• pp.19-26
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• 1996

A phospholipase C (PLC) inhibitor (MT267-2B) was isolated from the culture broth of actinomycetes isolate MT2617-2 by the extraction with n-butanol and column chromatographic techniques. The molecular weight of the inhibitor was 1057, by the spectroscopic analyses of IR, $^{13}C$-and $^{1}H$-NMR and ESI-MS. The chemical structure of MT2617-2B was found to be a macrolide compound consisted of a hemiketal ring, polyhydroxyl and polymethyl groups, which had a malonate and guanidine group as its side chain. MT2617-2B produced its two isomers having the same molecular weight by standing in methanol solution at room temperature. Therefore, MT2617-2B was identified as copiamycin and niphithricin A, macrolide antibiotics. The values of $IC_{50}$ against PLC-${\gamma}$1 and PLC-${\beta}$1 were 25 and 50${\mu}$g/ml, respectively. MT2617-2B had antimicrobial activities against Staphylococcus aureus and Candida albicans, but not against Escherichia coli.

• 대한약침학회지
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• 제5권2호
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• pp.40-51
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• 2002

Objectives : The purpose of this study was to investigate the effect of Bee Venom on the lipopolysaccharide-induced expression phospholipase $A_2$, cyclooxygenase-2 and inducible nitrogen oxide synthase, and the generation of arachidonic acid, prostaglandin D2 and E2 in RAW 264.7 cells, a murine macrophage cell line. Methods : The expression of phospholipase $A_2$, cyclooxygenase and inducible nitrogen oxide synthase was determined by western blotting with corresponding antibodies, and the generation of arachidonic acid, prostaglandin $D_2$ and $E_2$ was assayed by ELISA method in RAW 264.7 cells. The non-toxic concentrations (0.1 to $5\;{\mu}g/ml$) of bee venom determined by MTT assay, were used in this study. Results : 1. Bee venom inhibited lipopolysaccharide-induced expression of phospholipase $A_2$ in a dose dependent manner after 48 hours treatment. 2. Bee venom inhibited lipopolysaccharide-induced expression of cyclooxygenase-2 in a dose dependent manner after 24 and 48 hours treatment. 3. Bee venom inhibited lipopolysaccharide-induced expression of inducible nitrogen oxidesynthase in a dose dependent manner after 48 hours treatment. 4. The generation of arachidonic acid, prostaglandin $D_2$ and $E_2$ was not much affected by the treatment of bee venom on the lipopolysaccharide-induced generation of arachidonic acid, prostaglandin $D_2$ and $E_2$ in RAW 264.7 cells.

• 한국균학회지
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• 제24권3호통권78호
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• pp.237-242
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• 1996

Phospholipase $A_2(PLA_2)$는 생체막의 주요 구성성분인 인지질의 sn-2위치에서 지방산 ester 결합을 가수분해하는 효소로 염증과 관련된 질병에 있어서 매우 중요한 역할을 하는 것으로 알려졌다. 본 연구에서는 항염증 치료제의 개발을 목표로 $PLA_2$의 특이적 저해물질을 탐색하던 중 Umbilicaria esculenta석이(石耳)의 메탄올 추출물로부터 $PLA_2$ 저해활성을 갖는 두 화합물 G2, G3를 분리하였다. 활성물질의 분리는 U. esculenta의 메탄올 추출물을 에틸아세테이트로 추출하고 실리카 젤 컬럼, 크로로포름 추출, preparative TLC 등에 의하여 정제하였다. 각종 스펙트럼 분석 및 $^1H,\;^{13}C$, DEPT 등의 NMR 실험에 의하여 G2 화합물은 분자량 124, 분자식 $C_7H_8O_2$ 5-methyl-1,3-benzendiol(orcinol), G3 화합물은 분자량 182, 분자식 $C_9H_{10}O_4$의 2,4-dihydroxy-6-methyl-benzoic acid methyl ester(methyl orsellinic acid) 페놀성 화합물로 동정하였다. 본 화합물의 $PLA_2$ 저해활성은 $IC_{50}$값이 G2의 경우 0.22 mM, G3의 경우 0.26 mM이었다. 그 후 이 두 화합물의 in vivo 염증모델에서 그 효능을 검토할 예정이다.

• Journal of Microbiology and Biotechnology
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• 제28권12호
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• pp.2046-2056
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• 2018

Phospholipase D has great commercial value due to its transphosphatidylation products that can be used in the food and medicine industries. In order to construct a strain for use in the production of PLD, we employed a series of combinatorial strategies to increase PLD expression in Bacillus subtilis WB600. These strategies included screening of signal peptides, selection of different plasmids, and optimization of the sequences of the ribosome-binding site (RBS) and the spacer region. We found that using the signal peptide amyE results in the highest extracellular PLD activity (11.3 U/ml) and in a PLD expression level 5.27-fold higher than when the endogenous signal peptide is used. Furthermore, the strain harboring the recombinant expression plasmid pMA0911-PLD-amyE-his produced PLD with activity enhanced by 69.03% (19.1 U/ml). We then used the online tool \RBS Calculator v2.0 to optimize the sequences of the RBS and the spacer. Using the optimized sequences resulted in an increase in the enzyme activity by about 26.7% (24.2 U/ml). In addition, we found through a transfer experiment that the retention rate of the recombinant plasmid after 5 generations was still 100%. The final product, phosphatidylserine (PS), was successfully detected, with transphosphatidylation selectivity at 74.6%. This is similar to the values for the original producer.

• Archives of Pharmacal Research
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• 제24권6호
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• pp.552-556
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• 2001

Histamine and arachidonic acid (AA) release was measured using the P2-purinoceptor antaongists, phospholipase $A_2{\;}(PLA_2)$ and cyclooxygenase (COX)/lipoxygenase (LOX) inhibitors to determine whether or not ATP-induced histamine release is associated with arachidonic acid (AA) release in rat peritoneal mast cells. ATP increased histamine release in a dose dependent manner, whereas adenosine did not. PPADS (a selective P2X-purinoceptor antagonist) and suramin (a nonselective P2X,2Y-purinoceptor antagonist) inhibited ATP-induced histamine release in a dose dependent manner. However, RB-2 (a P2Y-purinoceptor antagonist) did not block ATP-induced histamine release. Manoalide and oleyloxyethyl phosphorylcholine (OPC), secretory PLA$_2$ inhibitors, also inhibited ATP-induced histamine release dose-dependently. Both COX inhibitors (ibuprofen and indomethacin) and LOX inhibitors (baicalein and caffeic acid) inhibited ATP-induced histamine in a dose dependent manner. ATP significantly increased [$^3H$]AA release by 54%. PPADS and suramin significantly inhibited ATP-induced [3H]Ph release by 81% and 39%, respectively. ATP-induced histamine release was significantly inhibited by a variety of protein kinase inhibitors, such as bisindolmaleimide, genistein, methyl 2,5-dihydroxycinnamate, W-7 and trifluoperazine. Overall, the results suggest that ATP-induced histamine release is in part related to the PLA2-mediated AA metabolism and P2X-purinoceptors.

• The Korean Journal of Physiology and Pharmacology
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• 제16권1호
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• pp.31-36
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• 2012

The receptor activator of NF-${\kappa}B$ ligand (RANKL) signal is an activator of tumor necrosis factor receptor-associated factor 6 (TRAF6), which leads to the activation of NF-${\kappa}B$ and other signal transduction pathways essential for osteoclastogenesis, such as $Ca^{2+}$ signaling. However, the intracellular levels of inositol 1,4,5-trisphosphate ($IP_3$) and $IP_3$-mediated cellular function of RANKL during osteoclastogenesis are not known. In the present study, we determined the levels of $IP_3$ and evaluated $IP_3$-mediated osteoclast differentiation and osteoclast activity by RANKL treatment of mouse leukemic macrophage cells (RAW 264.7) and mouse bone marrow-derived monocyte/macrophage precursor cells (BMMs). During osteoclastogenesis, the expression levels of $Ca^{2+}$ signaling proteins such as $IP_3$ receptors ($IP_3Rs$), plasma membrane $Ca^{2+}$ ATPase, and sarco/endoplasmic reticulum $Ca^{2+}$ ATPase type2 did not change by RANKL treatment for up to 6 days in both cell types. At 24 h after RANKL treatment, a higher steady-state level of $IP_3$ was observed in RAW264.7 cells transfected with green fluorescent protein (GFP)-tagged pleckstrin homology (PH) domains of phospholipase C (PLC) ${\delta}$, a probe specifically detecting intracellular $IP_3$ levels. In BMMs, the inhibition of PLC with U73122 [a specific inhibitor of phospholipase C (PLC)[ and of $IP_3Rs$ with 2-aminoethoxydiphenyl borate (2APB; a non-specific inhibitor of $IP_3Rs$) inhibited the generation of RANKL-induced multinucleated cells and decreased the bone-resorption rate in dentin slice, respectively. These results suggest that intracellular $IP_3$ levels and the $IP_3$-mediated signaling pathway play an important role in RANKL-induced osteoclastogenesis.