• 생명과학회지
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• 제31권10호
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• pp.898-904
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• 2021

본 연구는 lipopolysaccharide (LPS)로 자극된 RAW264.7 세포에 대한 풀무치 유래 항균 펩타이드 locustacin의 항염증 메커니즘을 조사하였다. Locustacin (50, 100, 200 ㎍/ml)은 세포 독성 없이 LPS로 자극된 대식세포의 nitric oxide (NO) 생성을 유의하게 감소시켰고, 단백질과 mRNA 수준에서 inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2)와 같은 전염증 매개체의 발현을 억제하였다. Locustacin은 LPS 처리로 증가된 염증성 사이토카인인 interleukin (IL)-6 및 IL-1β 함량과 이들의 유전자 발현을 모든 처리 농도에서 농도의존적으로 감소시켰다. 한편, LPS에 의해 인산화된 extracellular signal regulated kinase (ERK), p38 및 c-Jun N-terminal kinase (JNK)는 locustacin (100, 200 ㎍/ml) 처리로 억제되었다. 또한, LPS에 의해 유도된 inhibitory kappa B alpha (IκB-α)의 분해를 locustacin이 단백질 수준에서 억제한다는 것을 발견했다. 결론적으로, locustacin은 LPS 처리된 대식세포에서 mitogen-activated protein kinases (MAPKs) 인산화, nuclear factor kappa B (NF-κB) 활성화 및 하위 염증 매개체를 억제함으로써 항염증 효과를 가지고 있음을 확인하였다. 이러한 결과들은 풀무치 전사체 분석을 통해 확인된 locustacin이 항염증제 후보물질로서 개발 가능성이 있음을 제시한다.

• Biomolecules & Therapeutics
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• 제23권2호
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• pp.180-188
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• 2015

This study investigated the possible effects and molecular mechanisms of diallyl disulfide (DADS) against cyclophosphamide (CP)-induced hemorrhagic cystitis (HC) in rats. Inflammation response was assessed by histopathology and serum cytokines levels. We determined the protein expressions of nuclear transcription factor kappa-B (NF-${\kappa}B$), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), oxidative stress, urinary nitrite-nitrate, malondialdehyde (MDA), and 8-hydroxy-2'-deoxyguanosine (8-OHdG). Finally, we studied the involvement of mitogen-activated protein kinases (MAPKs) signaling in the protective effects of DADS against CP-induced HC. CP treatment caused a HC which was evidenced by an increase in histopathological changes, proinflammatory cytokines levels, urinary nitrite-nitrate level, and the protein expression of NF-${\kappa}B$, COX-2, iNOS, TNF-${\alpha}$, p-c-Jun N-terminal kinase (JNK), and p-extracellular signal regulated kinase (ERK). The significant decreases in glutathione content and glutathione-S-transferase and glutathione reductase activities, and the significant increase in MDA content and urinary MDA and 8-OHdG levels indicated that CP-induced bladder injury was mediated through oxidative DNA damage. In contrast, DADS pretreatment attenuated CP-induced HC, including histopathological lesion, serum cytokines levels, oxidative damage, and urinary oxidative DNA damage. DADS also caused significantly decreased the protein expressions of NF-${\kappa}B$, COX-2, iNOS, TNF-${\alpha}$, p-JNK, and p-ERK. These results indicate that DADS prevents CP-induced HC and that the protective effects of DADS may be due to its ability to regulate proinflammatory cytokines production by inhibition of NF-${\kappa}B$ and MAPKs expressions, and its potent anti-oxidative capability through reduction of oxidative DNA damage in the bladder.

• Nutritional Sciences
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• 제7권1호
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• pp.23-30
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• 2004

As a central component of a novel protein kinase cascade, the activation of the mitogen-activated protein (MAP) kinase cascade has attracted considerable attention. We sought to determine the effect of exercise and diet on the activation of the extracellular-signal regulated protein kinase (ERK) 1/2 and the p38 MAP kinase pathways in rat soleus muscle. Forty-eight Sprague-Dawley rats were assigned to one of two dietary conditions: high-carbohydrate (CHO) or high-fat (FAT). Animals having each dietary condition were further divided into one of three subgroups: a sedentary control group that did not exercise (NT), a group that performed 8 weeks of treadmill running and was sacrificed 48 h after their final treadmill run (CE), and a group that was sacrificed immediately after their final routine exercise training (AE). A high-fat diet did not have any significant effect on phosphorylated and total forms of ERK 1/2 or p38 MAP kinase. In chronically trained muscle that was taken 48 h after the last training, phosphorylated ERK 1/2 significantly increased only in the FAT but not in the CHO groups. In the case of total ERK 1/2, it increased significantly for both groups. In contrast, both phosphorylated and total forms of p38 MAP kinase decreased markedly compared to sedentary muscle. In muscle that was taken immediately after a last bout of exercise, phosphorylated ERK 1/2 increased in both groups but statistical significance was seen only in the CHO group. Total ERK 1/2 in acutely stimulated muscle increased only in the CHO-AE group even though the degree was much lower than the phosphorylated status. Muscle that was taken immediately after the routine training increased in phosphorylation status of p38 MAP kinase for both dietary conditions. However, statistical significance was seen only in the CHO group owing to a large variation with FAT. In conclusion, a high-fat diet per se did not have any notable effect versus a high-carbohydrate diet on MAP kinase pathways. However, when diet (either CHO or FAT) was combined with exercise and/or training, there was differentiated protein expression in MAP kinase pathways. This indicates MAP kinase pathways have diverse control mechanisms in slow-twitch fibers.

• 생명과학회지
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• 제8권5호
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• pp.614-621
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• 1998

열안정성 inulinase를 분비하는 Penicillium sp.를 돼지 감자 서식지의 토양으로부터 분리하여 이 균주의 inulinase를 50%-80% 염석, DEAE-Sephacel column chromatography, Toyopearl HW 65 F column chromatography에 의해 정제하여 inulinase 활성을 가진 단일 band를 얻었다. 이 band의 단백질을 polya-cryamide gel electrophoresis 후 추출하여 inulinase 활성을 가지는 것으로 확인되었다. 이 단백질의 분자량은 SDS-PAGE에 의해 약 77,000 dalton으로 추정되었고, 최종 정제도는 53.3배이었다. 정제된 효소의 효소학적 성질을 조사한 결과, 최적온도는 약 6$0^{\circ}C$이었고, 열 안정성은 30-5$0^{\circ}C$에서 비교적 안정하였다. pH 4에서 가장 높은 활성을 나타냈으며, pH 4-5에서는 비교적 안정했고 염기성에서는 아주 낮은 활성을 나타내었다. 금속이온과 다른 화학물질의 영향을 조사한 결과 1mM의 $MnCl_2$와 $CaCl_2$에 의해 활성이 증가했으며 특히, $MnCl_2$는 1.7배까지 활성을 증가시켰다. 그러나, 1mM의 $CuCl_2$,$HgCl_2$와 1mM EDTA 시에는 활성이 저해되었다. TLC분석결과 모든 산물이 monosaccharide였으므로 이 효소는 exo-acting inu-linase로 추정되었고, inulin에 대한 이 효소의 $K_M$치는 $2.2\times10^{-3}$이었다. 이 효소의 결정된 N-terminal 아미노산 배열은 $NH_2$-X-Glu-Tyr-Thr-Glu-Lys/Leu-Tyr-Arg-Pro이다.

• Asian Pacific Journal of Cancer Prevention
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• 제17권3호
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• pp.1519-1529
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• 2016

Background: Matrix metalloproteinase -2 (gelatinase-A, Mr 72,000 type IV collagenase, MMP-2) and -9 (gelatinase-B, Mr 92,000 type IV collagenase, MMP-9) are key molecules that play roles in tumor growth, invasion, tissue remodeling, metastasis and stem-cell regulation by digesting extracellular matrix barriers. MMP-2 and -9 are well known to impact on solid cancer susceptibility, whereas, in hematological malignancies, a paucity of data is available to resolve the function of these regulatory molecules in bone marrow mononuclear cells (BM-MNCs) and stromal cells of myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). Objectives: The present study aimed to investigate mRNA expression and gelatinase A and B secretion from BM-MNCs in vitro and genotypic associations of MMP-2 (-1306 C/T; rs243865), MMP-9 (-1562 C/T; rs3918242), tissue inhibitor of metalloproteinase -1 (TIMP-1) (372T/C; rs4898, Exon 5) and TIMP-2 (-418G/C; rs8179090) in MDS and AML. Results: The study covered cases of confirmed MDS (n=50), AML (n=32) and healthy controls (n=110). MMP-9 mRNA expression revealed 2 fold increased expression in MDS-RAEB II and 2.5 fold in AML M-4 (60-70% blasts). Secretion of gelatinase-B also revealed the MMP-9 mRNA expression and ELISA data also supported these data. We noted that those patients having more blast crises presented with more secretion of MMP-9 and its mRNA expression. In contrast MMP-9 (-1562 C/T) showed significant polymorphic associations in MDS (p<0.02) and AML (p<0.02). MMP-9 mRNA expression of C/T and T/T genotypes were 1.5 and 2.5 fold increased in MDS and AML respectively. In AML, MMP-2 C/T and T/T genotypes showed 2.0 fold mRNA expression. Only MMP-9 (-1306 C/T) showed significant 4 fold (p<0.001) increased risk with chemical and x-ray exposed MDS, while tobacco and cigarette smokers have 3 fold (p<0.04) risk in AML. Conclusions: In view of our results, MMP-9 revealed synergistic secretion and expression in blast crises of MDS and AML with 'gene' polymorphic effects and is significantly associated with increased risk with tobacco, cigarette and environmental exposure. Release and secretion of these enzymes may influence hematopoietic cell behavior and may be important in the clinical point of view. It may offer valuable tools for diagnosis and prognosis, as well as possible targets for the treatments.

• Asian-Australasian Journal of Animal Sciences
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• 제14권2호
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• pp.174-183
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• 2001

During the rapid phase of gonadal development of the freshwater teleost, the catfish (Silurus asotus), the influence of hCG upon the inducement of final oocyte maturation and spawning was investigated electrophoretically and ultrastructurally. The electrophoretic patterns obtained were different in the presence and absence of some of the major or minor zones, because of the hormone level in catfish. The vitellogenin of hormone-treated fish was stained more intensively than that of sham-treated fish. These proteins showed some minor or main bands of egg extracts which migrated at positions corresponding to molecular weights of approximately 90,000. However, the thickness of electrophoretic band in molecular weight for hCG-treated fish was slightly lower than that for saline control. It seemed the plasma protein with molecular weight of approximately 45,000 in hCG-treated fish disappeared. In contrast to the control fish, the ovaries in the catfish treated with hCG shows a marked ultrastructural change under the electron microscope. No dilated profiles were seen in the granulosa cells of the mature oocyte before ovulation. After germinal vesicle breakdown (GVBD), the zona radiata interna (ZRI) becomes more compact, and there is a loss of all the processes from the pore canals. There is a wide space between the vitelline membrane and zona radiata. Also, during final maturation, the microvillar processes from the oocyte are seen no longer to penetrate deeply into the extracellular spaces of the overlying granulosa cells, and the reticulate patterns of the zona radiata interna becomes occluded, giving the zona radiata a more solid appearance. It has been possible to initiate 100% oocyte maturation in yolk granules and follicles in vivo by treatment with hCG and a high water temperature ($27^{\circ}C$). In hCG-treated fish, the percentages of successful artificial fertilization and hatching were maximal at 15 h after a single injection. It seems clear that a long acting preparation containing hCG can be successfully used in prespawning fish to advance the final events of gonadal maturation and initiate spawning. Further studies are necessary to evaluate the potential of hCG to either stimulate or inhibit the reproductive development of fish at other stages of the seasonal reproductive cycle.

• 생명과학회지
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• 제20권6호
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• pp.914-921
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• 2010

항산화 기능과 면역 억제 기능을 갖는 것으로 알려진 melatonin이 혈관 내피층에서는 어떤 기능을 갖는지 알기 위한 일련의 실험을 수행하였다. 본 연구의 실험 결과, 혈관기능과 관련된 혈관내피세포의 성장, 사멸, 이동에 melatonin은 특이적인 효과를 나타내지 않았고, 백혈구의 혈관내피세포 부착과 백혈구 동종간의 응집에도 melatonin의 역할이 관찰되지 않았다. 이와는 대조적으로 melatonin은 PP2A를 통해 eNOS의 활성을 억제하여 산화질소의 양을 감소시키고, 이로 인해 혈관내피세포의 탈착이 유발되는 효과가 있음을 확인할 수 있었다. 종합해보면, 혈액 내 고농도의 melatonin은 PP2A 및 eNOS의 활성을 변화시켜 혈관내피세포의 탈착을 상승시킴으로써 혈관내에서 발생할 수 있는 혈전 형성에 의한 병리적 현상을 유발할 수 있다.

• Molecules and Cells
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• 제24권2호
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• pp.276-282
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• 2007

Protein phosphorylation is one of the major mechanisms by which eukaryotic cells transduce extracellular signals into intracellular responses. Calcium/calmodulin ($Ca^{2+}/CaM$)-dependent protein phosphorylation has been implicated in various cellular processes, yet little is known about $Ca^{2+}/CaM$-dependent protein kinases (CaMKs) in plants. From an Arabidopsis expression library screen using a horseradish peroxidase-conjugated soybean calmodulin isoform (SCaM-1) as a probe, we isolated a full-length cDNA clone that encodes AtCK (Arabidopsis thaliana calcium/calmodulin-dependent protein kinase). The predicted structure of AtCK contains a serine/threonine protein kinase catalytic domain followed by a putative calmodulin-binding domain and a putative $Ca^{2+}$-binding domain. Recombinant AtCK was expressed in E. coli and bound to calmodulin in a $Ca^{2+}$-dependent manner. The ability of CaM to bind to AtCK was confirmed by gel mobility shift and competition assays. AtCK exhibited its highest levels of autophosphorylation in the presence of 3 mM $Mn^{2+}$. The phosphorylation of myelin basic protein (MBP) by AtCK was enhanced when AtCK was under the control of calcium-bound CaM, as previously observed for other $Ca^{2+}/CaM$-dependent protein kinases. In contrast to maize and tobacco CCaMKs (calcium and $Ca^{2+}/CaM$-dependent protein kinase), increasing the concentration of calmodulin to more than $3{\mu}M$ suppressed the phosphorylation activity of AtCK. Taken together our results indicate that AtCK is a novel Arabidopsis $Ca^{2+}/CaM$-dependent protein kinase which is presumably involved in CaM-mediated signaling.

• 생명과학회지
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• 제17권11호
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• pp.1517-1522
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• 2007

간극결합(intercellular channel)은 인접하는 두 세포사이에 형성된 이온채널이며 이를 통해서 각종 이온, 이차 신호전달물질, 그리고 1 kDa 미만의 대사물질들이 통과한다. 아울러, sodium 혹은 potassium 이온채널처럼 반쪽의 간극결합(connexon 혹은 hemichannel)도 세포막채널로서 작용을 한다. 현재까지 간극결합을 구성하는 connexin (Cx) 단위체는 26종류 이상이 확인되었다. 이 가운데, Cx32, Cx38, Cx46 그리고 Cx50 만이 간극결합채널뿐만 아니라 세포막채널로서도 기능을 수행한다. Xenopus oocytes에서 connexin 38 (Cx38)이 발현하는 것으로 알려져 있지만 Cx38의 생물리학적 특성이 단일채널수준에서 연구가 진행된 경우는 없다. 이번 연구에서는 Cx38 채널의 생물리학적 특성, 즉 전압-의존적 개폐와 투과성(전기전도도와 이온선택성)을 알아보고자 단일채널기록을 수행하였다. Cx38 hemichannel은 전압-의존적인 빠른 개폐와 느린 개폐의 특성을 보였다. 양성전압 환경에서는 Cx38 채널이 낮은 열릴 확률(open probability)로 빠른 개폐가 유도된 반면, 음성전압에서는 느린 개폐가 높은 열릴 확률로 유도되었다. bi-ionic 실험을 통하여, Cx38 채널은 양이온보다 음이온을 더 선택 적으로 통과시킨다는 점을 알게 되었다. Cx38의 아미노산서열을 살펴보면, 아미노말단부위에 전하를 띠는 5개의 아미노산 잔기가 존재한다. 앞으로 이들 잔기를 치환시킨 돌연변이 Cx38 채널을 이용하여 과연 이들 아미노산 부위가 전압-의존적 개폐와 투과성에 관여하는 지 여부를 조사하는 연구는 매우 흥미로운 결과를 도출할 것으로 기대한다.

• 대한환경공학회지
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• 제38권6호
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• pp.323-328
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• 2016

공기주입형 가압식 MBR 공정은 일반적인 침지식 MBR 공정과 마찬가지로 정상 운전조건에서 막 오염에 대한 제어 및 관리 기술뿐만 아니라 저유량, 저부하 조건과 같은 비정상 운전조건에서도 시설의 운영에 지장이 없도록 막 오염에 대한 제어 대책이 필요하다. $85m^3$/일 규모의 공기주입형 가압식 MBR 실증시설 운영을 통해 공기주입에 의한 분리막 오염 저감효과와 비상 시 운전조건에서 미생물에 의해 나타날 수 있는 막 오염 문제를 고찰하였다. 가압식 분리막에서 공기의 주입은 분리막 표면에서 공기방울에 의한 scouring 효과에 의해 TMP 상승 기간을 연장시키고 처리의 안정성과 높은 효율의 플럭스($40L/m^2{\cdot}h$ 이상)를 장시간 유지할 수 있는 것으로 분석되었다. 비정상 운전조건에서는 생물반응조에 PACl (53 mg/L as Al)을 주입한 경우 19%의 TMP 상승 감소효과가 있었으나 MBR 공정의 비정상 운전조건 지속에 따른 반복적인 PACl의 주입은 질산화 미생물의 활성도에 영향을 미치게 되어 궁극적으로 질소 처리효율이 악화될 수 있음을 회분식 배양 실험을 통해 확인하였다. 생물반응조에 PAC (0.6 g/L)을 주입한 경우에서는 연속운전 5일 동안 TMP 상승 없이 운전 초기 TMP인 $0.2kg/cm^2$을 유지하여 안정적으로 운전이 가능하였다. 이것은 미생물의 성장 저해조건에서 막 오염 원인물질을 유발하는 EPS와 같은 고분자 물질의 흡착에 따른 것으로 판단된다.