• BMB Reports
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• 제52권10호
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• pp.613-618
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• 2019

Microglial cells are known as the main immune cells in the central nervous system, both regulating its immune response and maintaining its homeostasis. Furthermore, the antioxidant ${\alpha}-lipoic$ acid (LA) is a recognized therapeutic drug for diabetes because it can easily invade the blood-brain barrier. This study investigated the effect of ${\alpha}-LA$ on the inflammatory response in lipopolysaccharide (LPS)-treated BV-2 microglial cells. Our results revealed that ${\alpha}-LA$ significantly attenuated several inflammatory responses in BV-2 microglial cells, including pro-inflammatory cytokines, such as tumor necrosis $factor-{\alpha}$ and interleukin (IL)-6, and other cytotoxic molecules, such as nitric oxide and reactive oxygen species. In addition, ${\alpha}-LA$ inhibited the LPS-induced phosphorylation of ERK and p38 and its pharmacological properties were facilitated via the inhibition of the nuclear factor kappa B signaling pathway. Moreover, ${\alpha}-LA$ suppressed the activation of NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasomes, multiprotein complexes consisting of NLRP3 and caspase-1, which are involved in the innate immune response. Finally, ${\alpha}-LA$ decreased the genes accountable for the M1 phenotype, $IL-1{\beta}$ and ICAM1, whereas it increased the genes responsible for the M2 phenotype, MRC1 and ARG1. These findings suggest that ${\alpha}-LA$ alleviates the neuroinflammatory response by regulating microglial polarization.

• 한국식품영양과학회지
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• 제25권6호
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• pp.922-927
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• 1996

본 연구에서는 열처리에 의한 $알파-락트알부민(\alpha-La)겔의$ 특성을 규명하기 위하여 겔형성에 관여하는 인자들 즉, 염의 종류와 농도, pH, $\alpha-La$ 농도, 티올시약(NEM, Dn)의 농도를 각각 변화시켜 $90^{\circ}C에서$ 40분간 가열하여 만든 알파-락트알부민 겔의 총유리 SH그룹, half-cystine 함량, S-S 결합 함량을 측정하였다. 총 유리 SH 그룹, half-cystine 함량, S-S 결합은 첨가된 염의 종류와 농도 변화에는 큰 의존성을 나타내지 않았다. pH 2.5~3.5에서는 SH 그룹의 반응성이 낮아 pH 6.5~8.5에서의 총 유리 SH 그룹 보다 함량이 더 높고 half-cystine 함량은 일정하였으나 형성된 S-S 결합은 더 낮아 pH가 증가할수록 SH산화속도와 겔망상 구조의 형성 이 가속화됨을 확인할 수 있었다. $\alpha-La의$ 농도 증가로 half-cystine 함량은 큰 변화가 없었으나 총 유리 SH 그룹은 약간 감소하고 S-S 결합은 약간 증가하여 $\alpha-La의$ 농도 증가에 따라 겔지지체에서 S-S 결합의 관여가 큼을 나타내었다. NEM첨가의 경우는 총 유리 SH그룹과 half-cystine 함량이 급격히 감소하였으나 S-S 결합은 증가하여 NEM 첨가로 SH그룹이 반응성을 잃어 결국 $\alpha-La의$ 겔형성에 지장을 줌을 확인하였다. DTT 첨가로는 새로운 분자간 티올-이황화물 상호교환반응이 용이하게 되어 총 유리 SH 그룹은 낮고 S-S 결합은 높은 함량을 나타내었다.

• 대한의생명과학회지
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• 제19권1호
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• pp.1-8
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• 2013

Parkin is known to be a tumor suppressor protein. Previously, we determined that parkin expression restores susceptibility to TNF-${\alpha}$-induced death of HeLa cells, a human cervical cancer cell line resistant to TNF-${\alpha}$-induced cell death. MMP-3 is a zinc-dependent protease recently reported to activate intracellular apoptotic signaling. In this study we examined the regulation of MMP-3 expression by parkin in TNF-${\alpha}$-treated HeLa cells. Furthermore, we investigated the signaling pathway involved in parkin-induced expression of MMP-3. We found that HeLa cells exhibit low levels of MMP-3 but is induced after introduction of the parkin gene into HeLa cells. Furthermore, MMP-3 expression increased further when parkin expressing cells were treated with TNF-${\alpha}$. Using chemical inhibitors of cell signaling pathways, we found that MEK-1 (PD98059), PI3K (LY294002), p38 MAPK (SB203580), and JNK inhibitors alleviated parkin-induced up-regulation of MMP-3. Finally, we show that TNF-${\alpha}$-induced cell death in parkin expressing cells is inhibited by using a MMP-3 inhibitor. These results suggest that parkin expression induces prolonged expression of MMP-3 via MEK-1, PI3K, MAPK, and JNK pathway in HeLa cells allowing the HeLa cells to become sensitive to TNF-${\alpha}$-induced cell death. These results implicate a role of MMP-3 in parkin-induced cell death in TNF-${\alpha}$ treated HeLa cells.

• 한국식품과학회지
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• 제27권6호
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• pp.909-914
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• 1995

알파-락트알부민(${\alpha}-La$)의 열처리에 의한 겔 특성을 조사하기 위하여 ${\alpha}-La$ 농도, 염의 종류와 농도, 티올시약(NEM, DTT)의 농도를 달리해 $90^{\circ}C$에서 40분간 가열하여 만든 ${\alpha}-La$의 겔형성 시간과 용해성을 측정하였다. 겔형성 시간은 ${\alpha}-La$, NaCl, $CaCl_2$, DTT의 농도가 증가할수록 감소하였으나 NEM의 경우는 그와 반대로 나타났고 ${\alpha}-La$ 용액의 겔형성은 NEM $20{\sim}50\;mM$ 경우를 제외하고는 전부 40분 내에 이루어졌다. 용해성은 ${\alpha}-La$, NaCl, $CaCl_2$, DTT의 농도가 증가함에 따라 감소하였으나 NEM의 경우는 NEM의 농도증가에 따라 용해성은 증가하는 양상을 나타내었다. 표준완충용액에 용해된 겔의 용해성은 각각 $10.4{\sim}51.3%$, $9.2{\sim}35.4%$, $11.1{\sim}35.0%$, $8.0{\sim}9.5%$, 그리고 $96.8{\sim}56.2%$였고, 8M urea와 0.5% SDS를 함유한 표준완충용액에서는 더 높은 값인 $41.8{\sim}81.3%$, $41.9{\sim}64.1%$, $43.5{\sim}69.8%$, $29.6{\sim}38.5%$, 그리고 $77.4{\sim}98.9%$로 각각 나타났다. DTT를 함유한 것은 모든 조건에서 거의 100%에 달하는 용해성을 나타내었다. 이상으로 ${\alpha}-La$의 겔형성 속도와 용해성은 여러인자 즉, 단백질 농도, 염의 종류와 농도, 티올시약의 농도 등에 의해 영향을 받고, 겔형성 속도가 증가될수록 겔의 용해성은 감소함을 알수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제20권9호
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• pp.1327-1333
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• 2007

Lactose synthase catalyses the formation of lactose which is the major osmole of bovine milk and regulates the milk volume. Alpha-lactalbumin (${\alpha}$-LA) is involved in the synthesis of lactose synthase in the mammary gland. Therefore ${\alpha}$-LA is regarded as a plausible candidate gene for the milk yield trait. To determine whether ${\alpha}$-LA is associated with milk performance traits, 1,028 Chinese Holstein cows were used to detect polymorphisms in the ${\alpha}$-LA by means of single-strand conformation polymorphism (SSCP). Two nucleotide transitions were identified in the 5'flanking region and intron 3 of ${\alpha}$-LA. Associations of such polymorphisms with five milk performance traits were analyzed using a general linear model procedure. No significant associations were observed between these polymorphisms and the five milk performance traits (p>0.05). RH mapping placed ${\alpha}$-LA on BTA5q21, linked most closely to markers U63110, CC537786 and L10347 (LOD>8.3), which is far distant from the region of the quantitative trait locus (QTL) on bovine chromosome 5 for variation in the milk yield trait. In summary, based on our findings, we eliminated these SNPs from having an effect on milk performance traits.

• Applied Biological Chemistry
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• 제41권6호
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• pp.414-420
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• 1998

식이성지방 n-6/n-3비(1 : 2) 및 포화지방산:단순불포화지방산:다가불포화지방산비(1:1:1)를 일정하게 조정한 조건하에서 n-3계 지방산, ${\alpha}-LA(C_{18:3}),\;EPA(C_{20:5}),\;DHA(C_{22:6})$를 함유시킨 식이를 조제하여 성장기 SD-계 흰쥐 수컷에 2주간 급여하여 간장, 혈청의 Triacylglycerol(TG)농도 및 간장 TG 합성에 관여하는 효소 활성에 대하여 검토하였다. 본 실험에 사용한 EPA 및 DHA 는 순도 98%로서 고도로 정제한 ethyl ester 형태로 식이에 첨가하였다. 그 결과, ${\alpha}-LA$군에 비하여 EPA군 및 DHA군에서 간장 및 혈청 TG 농도는 유의적으로 감소하였으나, 총콜레스테롤 농도는 유의차가 인정되지 않았다. 간장의 인지질 농도는 DHA군에서만 유의적으로 증가하였다. 간장 막 결합성 phosphatidate phosphohydrolas(PAP)성은 간장TG 농도와 같은 경향으로서 EPA와 DHA군에서 유의하게 감소하였으며 Diacylglycerol acyltransferase(DGAT) 활성은 각 군간에는 변화가 없었다. 따라서, 간장TG 농도와 간장 막결합성 PAP활성과의 사이에 높은 상관관계(r=0.84)를 나타내어 간장TG 합성억제가 인정되었다. 지방산 합성계 효소의 활성도는 EPA및 DHA군에서 감소하였다. 이상의 결과로부터 n-3계 지방산, EPA 및 DHA에 의한 간장 및 혈청 TG 농도의 감소는 막 결합형 PAE 활성과 저해에 의한 간장TG 합성 및 지방산 합성 저해가 관여하는 것이 시사되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제27권6호
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• pp.907-915
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• 2014

Alpha-lipoic acid (${\alpha}$-LA) is not only involved in energy metabolism, but is also a powerful antioxidant that can protect against hepatic oxidative stress induced by some drugs, toxins, or under various physiological and pathophysiological conditions. Here, we investigated the effect of ${\alpha}$-LA against liver oxidative damage in broilers exposed to aflatoxin $B_1$ ($AFB_1$). Birds were randomly divided into four groups and assigned different diets: basal diet, 300 mg/kg ${\alpha}$-LA supplementation in basal diet, diet containing 74 ${\mu}g/kg$ $AFB_1$, and 300 mg/kg ${\alpha}$-LA supplementation in diet containing 74 ${\mu}g/kg$ $AFB_1$, for 3 weeks. The results revealed that the addition of 300 mg/kg ${\alpha}$-LA protected against the liver function damage of broilers induced by chronic low dose of $AFB_1$ as estimated by a significant (p<0.05) change in levels of plasma total protein, albumin, alkaline phosphatase and the activities of liver glutamic-oxalacetic transaminase and glutamic-pyruvic transaminase. The histopathological analysis also showed that liver tissues were injured in the $AFB_1$ diet, but this effect was alleviated by the addition of 300 mg/kg ${\alpha}$-LA. Additionally, $AFB_1$ induced a profound elevation of oxidative stress in birds, as indicated by an increase in malondialdehyde level, a decrease in glutathione peroxidase activity and a depletion of the glutathione content in the liver. All of these negative effects were inhibited by treatment with ${\alpha}$-LA. Our results suggest that the inhibition of $AFB_1$-induced excess production of lipid peroxides and the maintenance of intracellular antioxidant status may play important roles in the protective effects of ${\alpha}$-LA against $AFB_1$-induced oxidative damage in the liver.

• 한국수소및신에너지학회논문집
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• 제18권1호
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• pp.32-39
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• 2007

CO oxidation and selective CO oxidation of $La_xCe_{1-x}Co_yCu_{1-y}O_{3-{\alpha}}$ perovskite(x=1, 0.9, 0.7. 0.5; y=1, 0.9, 0.7, 0.5) were investigated. For CO oxidation, catalytic activities were studied according to different preparation conditions such as pH and calcination temperature. The influence of the change of the $O_2$ concentration for selective CO oxidation was studied, too. The substitution of Ce for La improved the catalytic activity for CO oxidation and selective CO oxidation and best activity was observed for $La_{0.7}Ce_{0.3}CoO_3$ prepared at pH 11 and calcined at $600^{\circ}C$. The temperature of 90% CO conversion for CO oxidation using $La_{0.7}Ce_{0.3}CoO_3$ was $230^{\circ}C$. In contrast to the enhancement effect by Ce substitution, the partial substitution of Cu for Co in $LaCo_yCu_{1-y}O_{3-{\alpha}}$ decreased catalytic activities for CO oxidation reaction compared to that using $LaCoO_3$. For selective CO oxidation, the best CO conversion was 66% at $230^{\circ}C$ for $La_{0.7}Ce_{0.3}CoO_3$. The CO conversion of $La_{0.7}Ce_{0.3}CoO_3$ was greatly increased from 66% to 91% as increasing $O_2$ concentration from 1% to 2%.

• 한국식품과학회지
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• 제26권4호
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• pp.436-441
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• 1994

Chymotrypsin, trypsin, pancreatin, 그리고 Aspergillus oryzae 유래 단백질분해효소의 in vitro처리에 의하여 유청단백질(WPI)의 가수분해물(WPH)중 ${\alpha}-LA$ 유래의 항원성변화를 조사하기 위하여 토끼 항 ${\alpha}-LA$ 항혈청을 이용한 competitive inhibition ELISA(cELISA)와 heterologous PCA를 실시하였다. cELISA에 의하여 WPH의 monovalent항원성을 분석한 결과, pepsin전처리는 chymotrypsin, trypsin 그러고 pancreatin 가수분해물의 항원성을 더욱 감소시키는 효과가 있었으며, 열 전처리는 Asp. oryzae 유래효소 및 trypsin 가수분해물의 항원성을 더욱 감소시켰다 전체적으로 ${\alpha}-LA$유래의 monovalent 항원성은 효소처리에 의하여 $10^{-2.5}-10^{-5.5}$배 또는 그 이하로 저하되었으며, 특히 열 및 pepsin 전처리후 trypsin으로 가수분해한 경우(TDP)의 항원성은 거의 상실되었다. WPH의 가수분해도와 ${\alpha}-LA$유래의 monovalent 항원성 감소는 그다지 일치하지 않았다. Guinea pig를 이용한 PCA test에 의하여 ${\alpha}-LA$유래의 polyvalent 항원성을 분석한 결과 WPI 및 ${\alpha}-LA$는 양성으로 높게 나타났으나, WPH는 전처리유무에 관계없이 모두 음성으로 나타났다. 이는 WPI의 가수분해로 생성된 ${\alpha}-LA$유래의 peptide가 특이항체와 결합은 가능하나 생체내에서 알레르기를 유발하지 않음을 뜻하였다. 따라서, 유청단백질을 효소로 가수분해하면 유청단백질중 ${\alpha}-LA$의 allergenicity는 쉬 파괴됨을 알 수 있었다.

• 한국축산식품학회지
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• 제29권4호
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• pp.415-422
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• 2009

In this study, several factors were analyzed in an effort to determine the effects of transglutaminase (TGase) treatment on sodium caseinate (NaCN), ${\alpha}--lactalbumin$ (${\alpha}-La$), and ${\beta}-lactoglobulin$ (${\beta}-Lg$) polymerization reactions. The results of SDSPAGE showed that NaCN was slightly hydrolyzed to molecular weights of 50-400 kDa according to activation time. ${\alpha}-La$ formed high-molecular polymers of 30-300 kDa, whereas ${\beta}-Lg$ remained almost completely unhydrolyzed. Melting temperatures of NaCN, ${\alpha}-La$ with and without TGase were all in the range of $100{\pm}10^{\circ}C$ under the endothermic curve, and the melting temperature of ${\beta}-Lg$ with TGase was lower than that with TGase. When the proteins were incubated for 3 h with TGase, the micrographic structures showed a small quantity of sediment and broad layers. The final ${\alpha}-La$ residues remained at a level of 21.38%, and the TGase-treated ${\alpha}-La$ was confirmed to have undergone a profound loss of mass, to 18.25%. The DPPH-radical scavenging activity of NaCN and ${\beta}-Lg$ with TGase treatment was higher than that observed in the untreated sample, while those of ${\alpha}-La$ increased with concentration.