• Molecules and Cells
• /
• 제41권11호
• /
• pp.964-970
• /
• 2018

Atherosclerosis preferentially involves in prone area of low and disturbed blood flow while steady and high levels of laminar blood flow are relatively protected from atherosclerosis. Disturbed flow induces endoplasmic reticulum (ER) stress and the unfolded protein response (UPR). ER stress is caused under stress that disturbs the processing and folding of proteins resulting in the accumulation of misfolded proteins in the ER and activation of the UPR. Prolonged or severe UPR leads to activate apoptotic signaling. Recent studies have indicated that disturbed flow significantly up-regulated $p-ATF6{\alpha}$, $p-IRE1{\alpha}$, and its target spliced XBP-1. However, the role of laminar flow in ER stress-mediated endothelial apoptosis has not been reported yet. The present study thus investigated the role of laminar flow in ER stress-dependent endothelial cell death. The results demonstrated that laminar flow protects ER stress-induced cleavage forms of PARP-1 and caspase-3. Also, laminar flow inhibits ER stress-induced $p-eIF2{\alpha}$, ATF4, CHOP, spliced XBP-1, ATF6 and JNK pathway; these effects are abrogated by pharmacological inhibition of PI3K with wortmannin. Finally, nitric oxide affects thapsigargin-induced cell death in response to laminar flow but not UPR. Taken together, these findings indicate that laminar flow inhibits UPR and ER stress-induced endothelial cell death via PI3K/Akt pathway.

• Bulletin of the Korean Chemical Society
• /
• 제26권8호
• /
• pp.1225-1228
• /
• 2005

C-terminal fragments of APP (APP-CTs), that contain A$\beta$ sequence, are found in neurotic plaques, neurofibrillary tangles and the cytosol of lymphoblastoid cells obtained from AD patients. CT26, Thr639-Asp664 (TVIVITLVMLKKKQYTSIHH GVVEVD) includes not only the transmembrane domain but also the cytoplasmic domain of APP. This sequence is produced from cleavage of APP by caspase and $\gamma$-secretase. In this study, the solution structure of CT26 was investigated using NMR spectroscopy and circular dichroism (CD) spectropolarimeter in various membrane-mimicking environments. According to CD spectra and the tertiary structure of CT26 determined in TFE-containing aqueous solution, CT26 has an α-helical structure from $Val^{2}\;to\;Lys^{11}$ in TFE-containing aqueous solution. However, according to CD data, CT26 adopts a $\beta$-sheet structure in the SDS micelles and DPC micelles. This result implies that CT26 may have a conformational transition between $\alpha$-helix and $\beta$-sheet structure. This study may provide an insight into the conformational basis of the pathological activity of the C-terminal fragments of APP in the model membrane.

• Animal cells and systems
• /
• 제11권1호
• /
• pp.23-31
• /
• 2007

Programmed cell death was characterized in the silkworm thoracic ganglia TG1, TG2 and TG3 during postembryonic periods by TUNEL assay. Apoptotic cells were detected in the three TGs of all larval stages except for day-1, 2 1st instar larvae, in which no apoptotic cells were found. From day-7 5th larva, the numbers of apoptotic cells were dramatically increased and peaked on day-1 pupa and day-2 pupa and then abruptly decreased. Apoptotic cells finally disappeared in day-1 adult. In-vivo injection of 20-hydroxyecdysone (20E) into day-8 5th larva resulted in a striking decrease of apoptotic cells. Actinomycin D (Act D) or cycloheximide (CHX), injected into hemolymph of day-8 5th larva, resulted in a decrease of apoptotic cells in the three TGs. Injection of caspase-8 and -3 inhibitors also blocked cellular apoptosis. These results will provide valuable information for understanding of cellular changes in the three TGs during metamorphosis of the insect species.

• Animal Bioscience
• /
• 제34권11호
• /
• pp.1859-1869
• /
• 2021

Objective: The effects of a crude protease extracted from Cordyceps militaris (CM) mushrooms on the postmortem tenderization mechanism and quality improvement in spent hen breast were investigated. Methods: Different percentages of the crude protease extracted from CM mushrooms were introduced to spent hen breast via spray marination, and its effects on tenderness-related indexes and proteolytic enzymes were compared to papain. Results: The results indicated that there was a possible improvement by the protease extracted from CM mushroom through the upregulation of endogenous proteolytic enzymes involved in the calpain system, cathepsin-B, and caspase-3 coupled with its nucleotide-specific impact. However, the effect of the protease extracted from CM mushroom was likely dose-dependent, with significant improvements at a minimum level of 4%. Marination with the protease extracted from CM mushroom at this level led to increased protein solubility and an increased myofibrillar fragmentation index. The sarcoplasmic protein and collagen contents seemed to be less affected by the protease extracted from CM mushroom, indicating that substrate hydrolysis was limited to myofibrillar protein. Furthermore the protease extracted from CM mushroom intensified meat product taste due to increasing the inosinic acid content, a highly effective salt that provides umami taste. Conclusion: The synergistic results of the proteolytic activity and nucleotide-specific effects following treatments suggest that the exogenous protease derived from CM mushroom has the potential for improving the texture of spent hen breast.

• 대한융합한의학회지
• /
• 제4권1호
• /
• pp.5-11
• /
• 2022

Objectives: Inflammasomes are molecular platforms that are generated inside cytoplasmic compartments. The objective is to mediate immunological responses of the host to cell damage and infection. Caspase-1 is triggered by inflammasome to generate interleukin-1𝛽 (IL-1𝛽), an inflammatory cytokine, and pyroptosis, an inflammatory form of apoptosis. Methods: In the past two decades, scientists have uncovered several inflammasomes. The most research has been conducted on NLRP3 inflamamsomes, whose activity can be stimulated by a variety of induction factors. However, the unregulated activation of NLRP3 inflammasomes is also a role in the etiology of several human disorders. Previous research has demonstrated that NLRP3 inflammasomes have a significant role in the innate and acquired immune systems, as well as in the prevalence of joint illnesses such rheumatoid arthritis. Conclusion: Within the scope of this review, we will present a brief overview of the biological features of NLRP3 inflamamsomes as well as a description of the underlying mechanisms governing activation and regulation. In particular, we explore the function of inflammasomes in the development of rheumatoid arthritis as well as the promise of recently identified medicines that target inflamasomes.

• 한국수정란이식학회지
• /
• 제25권3호
• /
• pp.171-177
• /
• 2010

Plasminogen activators (PAs) are serine proteases that convert plasminogen to plasmin. The PA/plasmin system has been associated with a number of physiological processes such as fibrinolysis, ovulation and fertilization. Although correlations have been reported between reactive oxygen species (ROS) and oocyte maturation, the relationship between PA activity and ROS is unknown. The present study was undertaken to determine the effects of cumulus cells on PA activity in matured porcine oocytes under xanthine (X)-xanthine oxidase (XO) system. When oocytes were matured under the X-XO system, the proportion of oocytes remaining GV stage was higher (p<0.05) in oocytes without cumulus cells. The incidence of degenerated oocytes was higher (p<0.05) in the X+XO ($11.1{\pm}6.1$ and $21.6{\pm}3.4%$) than in the control group ($2.9{\pm}1.8$ and $4.0{\pm}1.6%$). The proportion of TUNEL-positive oocytes and activity of caspase-3 were higher (p<0.05) in cumulus-free oocytes and oocytes exposed to ROS. Tissue-type plasminogen activator-plasminogen activator inhibitor (tPA-PAI) and tissue-type plasminogen activator (tPA) activity were detected in oocytes that were separated from cumulus-oocytes complexs (COCs) at 44 h of maturation culture, and only tPA was produced in oocytes that were denuded before the onset of maturation culture. On the other hand, the activities of PA were increased (p<0.05) when oocytes were cultured under the X-XO system. The higher activity of tPA was observed in denuded oocytes (DOs) underwent apoptotic changes by oxidative stress. In COCs, however, tPA-PAI as well as tPA activity was detected and apoptotic changes such as DNA cleavage or caspase-3 activation were not observed. These results suggest that tP A may be relevant to apoptotic cell death in porcine oocytes by oxidative stress.

• Journal of Acupuncture Research
• /
• 제27권3호
• /
• pp.105-116
• /
• 2010

목적 : 이 연구는 MPTP 유발 파킨슨병 동물 모델에서 봉독약침의 신경보호 효과 및 항염증 효과를 확인하기 위해 시행되었다. 방법 : C57BL/6 mice에 신경독소인 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)를 하루에 2시간 간격으로 MPTP-HCl(20mg/kg per dose)을 4번 복강 내 주입하여 중뇌 흑질의 도파민 신경세포를 파괴한 파킨슨병 동물 모델을 유발하였다. 실험군은 MPTP군, MPTP 현종 BVA군, MPTP 곡지 BVA군, MPTP 신수 BVA군의 4군으로 하였다. 마지막 MPTP 투여 2시간 후에 1차로 봉독약침을 시술하고, 그 후 48시간 간격으로 총 5차 연속 시술하였다. 봉독약침액의 농도는 0.2mg/Kg으로 하였고, 경혈은 양측 현종($GB_{39}$), 곡지($LI_{11}$), 신수($BL_{23}$)를 사용했고, 주입량은 각 경혈당 양측으로 각 $20{\mu\ell}$씩 주입하였다. 항염증작용을 알아보기 위해 TH, MAC-1, iNOS HSP70을, 세포사멸에 대한 신경세포의 보호효과를 알아보기 위해 caspase-3을 면역조직화학법을 사용하여 실시하였다. 결과 : 실험 결과 MPTP 유발 파킨슨병 동물 모델에서 현종 곡지 신수혈에 대한 봉독약침은 TH-Immunoreactivity neuron의 감소와 microglial activation을 억제하였다. 봉독약침군 모두 효과를 보였으나 그 중 현종과 신수혈에서 특히 억제작용이 컸다. MAC-1에서는 현종혈이 억제작용이 컸다. HSP70-IR neuron은 곡지에서 유의한 억제작용을 보였으나, iNOS neuron은 모든 군에서 유의한 차이를 보이지 않았다. 또한 세포사멸억제여부 실험에서 봉독약침은 모두 억제작용을 보였으나 특히 곡지자침군에서 caspase-3 발현을 유의하게 억제하였다. 결론 : 이러한 결과는 봉독약침이 MPTP 투여로 인한 중뇌 흑질의 염증에 의한 도파민 신경세포 손상을, 염증을 억제함으로써 항염 효과를 나타냄을 알 수 있으며, 신경세포를 보호하는 활성이 있음을 보여줌과 동시에 세포사멸을 억제하는 활성이 있다고 사료된다.

• Journal of Periodontal and Implant Science
• /
• 제41권1호
• /
• pp.17-22
• /
• 2011

Purpose: Nitric oxide (NO) has been known as an important regulator of osteoblasts and periodontal ligament cell activity. This study was performed to investigate the relationship between NO-mediated cell death of human periodontal ligament fibroblasts (PDLFs) and N-methyl-D-aspartic acid (NMDA) receptor antagonist (+)-5-methyl-10, 11-dihydro-5H-dibenzo[a,d]cyclohepten-5, 10-imine hydrogen maleate (MK801). Methods: Human PDLFs were treated with various concentrations (0 to 4 mM) of sodium nitroprusside (SNP) with or without $200\;{\mu}M$ MK801 in culture media for 16 hours and the cell medium was then removed and replaced by fresh medium containing MTS reagent for cell proliferation assay. Western blot analysis was performed to investigate the effects of SNP on the expression of Bax, cytochrome c, and caspase-3 proteins. The differences for each value among the sample groups were compared using analysis of variance with 95% confidence intervals. Results: In the case of SNP treatment, as a NO donor, cell viability was significantly decreased in a concentration-dependent manner. In addition, a synergistic effect was shown when both SNP and NMDA receptor antagonist was added to the medium. SNP treated PDLFs exhibited a round shape in culture conditions and were dramatically reduced in cell number. SNP treatment also increased levels of apoptotic marker protein, such as Bax and cytochrome c, and reduced caspase-3 in PDLFs. Mitogen-activated protein kinase signaling was activated by treatment of SNP and NMDA receptor antagonist. Conclusions: These results suggest that excessive production of NO may induce apoptosis and that NMDA receptor may modulate NO-induced apoptosis in PDLFs.

• 생명과학회지
• /
• 제20권10호
• /
• pp.1443-1450
• /
• 2010

Honokiol은 작은 분자량을 갖는 중국의 약초인 'Magnolia officinalis'에서 추출한 리간드로서 중국과 일본에서 전통 의약제로 사용되어 왔다. 이전 연구에서는 honokiol이 다양한 종류의 암에서anti-angiogenic, anti-invasive, anti-proliferative activities 등의 다양한 효과가 있는 것으로 알려져 있다. 우리는 이전 연구에서 Nitric oxide donor인 sodium nitroprusside (SNP)에 의해서 토끼 무릎관절연골세포에서 세포사멸이 일어나는 것을 보고하였다. 본 연구에서는 무릎 연골세포에서 NO에 의해 유도되는 세포사멸이 honokiol 처리농도에 의존적으로 억제되는 것을 세포형태, MTT assay, Western blot analysis 그리고 FACS를 통해 확인할 수 있었다. 또한, honokiol은 SNP에 의해 유도되는 p53의 발현 및 pro-caspase-3의 활성 저해, DNA fragmentation을 억제하였다. Honokiol에 의한 세포사멸 억제는 PI-3K의 특정 저해제인 LY294002를 SNP와 honokiol과 함께 처리하였을 때 세포의 사멸이 증가하는 것을 확인할 수 있었다. 이는 honokiol이 PI-3K/AKT pathway를 통하여 NO가 유도하는 세포사멸을 억제하는 것을 의미한다.

• 한방재활의학과학회지
• /
• 제18권4호
• /
• pp.1-11
• /
• 2008

목적 : 뇌허혈은 일시적 혹은, 영구적 뇌동맥 폐색에 의한 뇌혈류의 감소로 유발되며, 허혈 부위에서는 복잡한 병태 생리적 과정을 통하여 신경 세포사가 초래되어 비가역적인 신경학적 손상을 일으킨다. 본 연구에서는 모래쥐를 대상으로 일시적인 전뇌허혈을 유발 시킨 후 해마 치상회에서 허혈로 인한 세포사멸을 관찰하고, 현삼(玄蔘)의 투여가 허혈로 유발된 해마 치상회에서 세포사멸에 미치는 영향과 단기 기억에 미치는 효과를 규명하고자 실험하였다. 연구방법 : 세포사멸은 DNA 분절을 나타내는 terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) 염색법과 단백분해 과정의 마지막 단계에 발현되는 caspase-3에 대한 면역조직화학법을 이용하였고, 단기기억은 step-down avoidance task를 실시하여 평가하였다. 결과 : 본 실험의 결과 일시적인 전뇌허혈은 해마 치상회의 세포사멸을 유의하게 증가시켰으며 단기기억을 감소시켰다. 현삼의 투여는 허혈로 증가된 해마 치상회의 세포사멸을 유의하게 억제하였고, 허혈로 인한 단기 기억의 감소를 유의하게 억제시켰다. 결론 : 본 실험을 통하여 현삼은 뇌허혈로 증가된 세포사멸을 억제하고 단기 기억을 향상시킴을 알 수 있었고, 따라서 현삼은 뇌허혈로 인한 뇌손상을 보호할 수 있는 효과가 있음을 제시하는 바이다.