• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1996년도 춘계학술대회
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• pp.19-29
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• 1996

The neurological manifestations of AIDS include dementia, encountered even in the absence of opportunistic superinfection or malignancy. The AIDS Dementia Complex appears to be associated with several neuropathological abnormalities, including astrogliosis and neuronal injury or loss. How can HIV-1 result in neuronal damage if neurons themselves are only rarely, if ever, infected by the vitus\ulcorner In vitro experiments from several different laboratiories have lent support to the existence of HIV- and immune-related toxins. In one recently defined pathway to neuronal injury, HIV-infected macrophages/microglia as well as macrophages activated by HIV-1 envelope protein gp120 appear to secrete excitants/neurotoxins. These substances may include arachidonic acid, platelet-activating factor, free radicals (NO - and O$_2$), glutamate, quinolinate, cysteine, cytokines (TNF-${\alpha}$, IL1-B, IL-6), and as yet unidentified factors emanating from stimulated macrophages and possibly reactive astrocytes. A final common pathway for newonal suscepubility appears to be operative, similar to that observed in stroke, trauma, epilepsy, and several neurodegenerative diseases, including Huntington's disease, Parkinson's disease, and amyotrophic lateral sclerosis. This mechanism involves excessive activation of N-methyl-D-aspartate (NMDA) receptor-operated channels, with resultant excessive influx of Ca$\^$2+/ leading to neuronal damage, and thus offers hope for future pharmacological intervention. This chapter reviews two clinically-tolerated NMDA antagonists, memantine and nitroglycerin; (ⅰ) Memantine is an open-channel blocker of the NMDA-associated ion channel and a close congener of the anti-viral and anti-parkinsonian drug amantadine. Memantine blocks the effects of escalating levels of excitotoxins to a greater degree than lower (piysiological) levels of these excitatory amino acids, thus sparing to some extent normal neuronal function. (ⅱ) Niuoglycerin acts at a redox modulatory site of the NMDA receptor/complex to downregulate its activity. The neuroprotective action of nitroglycerin at this site is mediated by n chemical species related to nitric oxide, but in a higher oxidation state, resulting in transfer of an NO group to a critical cysteine on the NMDA receptor. Because of the clinical safety of these drugs, they have the potential for trials in humans. As the structural basis for redox modulation is further elucidated, it may become possible to design even better redox reactive reagents of chinical value. To this end, redox modulatory sites of NMDA receptors have begun to be characterized at a molecular level using site-directed mutagenesis of recombinant subunits (NMDAR1, NMDAR2A-D). Two types of redox modulation can be distinguished. The first type gives rise to a persistent change in the functional activity of the receptor, and we have identified two cysteine residues on the NMDARI subunit (#744 and #798) that are responsible for this action. A second site, presumably also a cysteine(s) because <1 mM N-ethylmaleimide can block its effect in native neurons, underlies the other, more transient redox action. It appears to be at this, as yet unidentified, site on the NMDA receptor that the NO group acts, at least in recombinant receptors.

• Asian-Australasian Journal of Animal Sciences
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• 제32권8호
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• pp.1112-1121
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• 2019

Objective: Gram-negative bacteria lipopolysaccharide (LPS) has been reported to be associated with uterine impairment, embryonic resorption, ovarian dysfunction, and follicle retardation. Here, we aimed to investigate the toxic effects of LPS on the maturation ability and parthenogenetic developmental competence of bovine oocytes. Methods: First, we developed an in vitro model to study the response of bovine cumulusoocyte complexes (COCs) to LPS stress. After incubating germinal vesicle COCs in $10{\mu}g/mL$ of LPS, we analyzed the following three aspects: the expression levels of the LPS receptor toll-like receptor 4 (TLR4) in COCs, activities of intracellular signaling protein p38 mitogen-activated protein kinase (p38 MAPK) and nuclear factor-kappa B (NF-${\kappa}B$); and the concentrations of interleukin (IL)-$1{\beta}$, tumor necrosis factor (TNF)-${\alpha}$, and IL-6. Furthermore, we determined the effects of LPS on the maturation ability and parthenogenetic developmental competence of bovine oocytes. Results: The results revealed that LPS treatment significantly elevated TLR4 mRNA and protein expression levels in COCs. Exposure of COCs to LPS also resulted in a marked increase in activity of the intracellular signaling protein p-p38 MAPK and NF-${\kappa}B$. Furthermore, oocytes cultured in maturation medium containing LPS had significantly higher concentrations of the proinflammatory cytokines IL-$1{\beta}$, TNF-${\alpha}$, and IL-6. LPS exposure significantly decreased the first polar body extrusion rate. The cytoplasmic maturation, characterized by polar body extrusion and distribution of peripheral cortical granules, was significantly impaired in LPS-treated oocytes. Moreover, LPS exposure significantly increased intracellular reactive oxygen species levels and the relative mRNA abundance of the antioxidants thioredoxin (Trx), Trx2, and peroxiredoxin 1 in oocytes. Moreover, the early apoptotic rate and the release of cytochrome C were significantly increased in response to LPS. The cleavage, morula, and blastocyst formation rates were significantly lower in parthenogenetically activated oocytes exposed to LPS, while the incidence of apoptotic nuclei in blastocysts was significantly increased. Conclusion: Together, these results provide an underlying mechanism by which LPS impairs maturation potential in bovine oocytes.

• Molecules and Cells
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• 제41권3호
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• pp.244-255
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• 2018

Low-grade pro-inflammatory state and leptin resistance are important underlying mechanisms that contribute to obesity-associated hypertension. We tested the hypothesis that Astragaloside IV (As IV), known to counteract obesity and hypertension, could prevent obesity-associated hypertension by inhibiting pro-inflammatory reaction and leptin resistance. High-fat diet (HFD) induced obese rats were randomly assigned to three groups: the HFD control group (HF con group), As IV group, and the As IV + ${\alpha}$-bungaratoxin (${\alpha}-BGT$) group (As IV+${\alpha}-BGT$ group). As IV ($20mg{\cdot}Kg^{-1}{\cdot}d^{-1}$) was administrated to rats for 6 weeks via daily oral gavage. Body weight and blood pressure were continuously measured, and NE levels in the plasma and renal cortex was evaluated to reflect the sympathetic activity. The expressions of leptin receptor (LepRb) mRNA, phosphorylated signal transducer and activator of transcription-3 (p-STAT3), phosphorylated phosphatidylinositol 3-kinase (p-PI3K), suppressor of cytokine signaling 3 (SOCS3) mRNA, and protein-tyrosine phosphatase 1B (PTP1B) mRNA, pro-opiomelanocortin (POMC) mRNA and neuropeptide Y (NPY) mRNA were measured by Western blot or qRT-PCR to evaluate the hypothalamic leptin sensitivity. Additionally, we measured the protein or mRNA levels of ${\alpha}7nAChR$, inhibitor of nuclear factor ${\kappa}B$ kinase subunit ${\beta}/nuclear$ factor ${\kappa}B$ ($IKK{\beta}/NF-KB$) and pro-inflammatory cytokines ($IL-1{\beta}$ and $TNF-{\alpha}$) in hypothalamus and adipose tissue to reflect the anti-inflammatory effects of As IV through upregulating expression of ${\alpha}7nAChR$. We found that As IV prevented body weight gain and adipose accumulation, and also improved metabolic disorders in HFD rats. Furthermore, As IV decreased BP and HR, as well as NE levels in blood and renal tissue. In the hypothalamus, As IV alleviated leptin resistance as evidenced by the increased p-STAT3, LepRb mRNA and POMC mRNA, and decreased p-PI3K, SOCS3 mRNA, and PTP1B mRNA. The effects of As IV on leptin sensitivity were related in part to the up-regulated ${\alpha}7nAchR$ and suppressed $IKK{\beta}/NF-KB$ signaling and pro-inflammatory cytokines in the hypothalamus and adipose tissue, since co-administration of ${\alpha}7nAChR$ selective antagonist ${\alpha}-BGT$ could weaken the improved effect of As IV on central leptin resistance. Our study suggested that As IV could efficiently prevent obesityassociated hypertension through inhibiting inflammatory reaction and improving leptin resistance; furthermore, these effects of As IV was partly related to the increased ${\alpha}7nAchR$ expression.

• 한국자원식물학회지
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• 제34권5호
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• pp.411-419
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• 2021

본 연구에서 금화규 뿌리 추출물(AMR)이 마우스 대식세포인 RAW264.7 세포의 활성화 유도를 통한 면역증진 활성과 마우스 지방전구세포인 3T3-L1 세포의 지질축적억제를 통한 항비만 활성을 평가하였다. 금화규 뿌리 추출물(AMR)은 전반적으로 RAW264.7 세포에서 TLR2/TLR4의 자극을 통해 p38과 JNK를 활성화시켜 NO, iNOS, IL-1𝛽, IL-6, TNF-𝛼와 같은 면역증진 인자의 발현을 증가시키는 것으로 판단된다. 그러나 IL-6의 경우, p38과 JNK 활성화에 의존하지 않는 것으로 확인되어 TLR2/4에 의한 다른 신호전달이 관여하는 것으로 사료되어 추가적인 연구가 필요하다. 또한, 금화규 뿌리 추출물(AMR)은 PPAR𝛾의 과대발현을 억제하여 지방전구세포의 성숙한 지방세포로의 분화를 억제하고, 성숙한 지방세포에서 CEBP𝛼, PPAR𝛾, perilipin-1, FABP4, adiponectin의 발현을 억제하여 지방세포 내 지질 형성 및 축적을 억제하는 것으로 판단된다. 본 연구를 통해 구명된 결과들은 금화규 뿌리 추출물(AMR)이 향후 면역증진 및 항비만을 위한 보조제 또는 건강 기능성 식품과 의약품으로의 개발 및 활용이 가능할 것으로 생각된다.

• Parasites, Hosts and Diseases
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• 제57권4호
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• pp.379-387
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• 2019

Clonorchis sinensis is a carcinogenic human liver fluke that promotes hepatic inflammatory environments via direct contact or through their excretory-secretory products (ESPs), subsequently leading to cholangitis, periductal fibrosis, liver cirrhosis, and even cholangiocarcinoma (CCA). This study was conducted to examine the host inflammatory responses to C. sinensis ESPs and their putative protein components selected from C. sinensis expressed sequenced tag (EST) pool databases, including $TGF-{\beta}$ receptor interacting protein 1(CsTRIP1), legumain (CsLeg), and growth factor binding protein 2 (CsGrb2). Treatment of CCA cells (HuCCT1) with the ESPs or bacterial recombinant C. sinensis proteins differentially promoted the secretion of proinflammatory cytokines ($IL-1{\beta}$, IL-6, and $TNF-{\alpha}$) as well as anti-inflammatory cytokines (IL-10, $TGF-{\beta}1$, and $TGF-{\beta}2$) in a time-dependent manner. In particular, recombinant C. sinensis protein treatment resulted in increase (at maximum) of ~7-fold in $TGF-{\beta}1$, ~30-fold in $TGF-{\beta}2$, and ~3-fold in $TNF-{\alpha}$ compared with the increase produced by ESPs, indicating that CsTrip1, CsLeg, and CsGrb2 function as strong inducers for secretion of these cytokines in host cells. These results suggest that C. sinensis ESPs contribute to the immunopathological response in host cells, leading to clonorchiasis-associated hepatobiliary abnormalities of greater severity.

• Journal of Microbiology and Biotechnology
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• 제32권2호
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• pp.256-262
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• 2022

Panax ginseng C. A. Meyer is well known as traditional herbal medicine, and ginseng berries are known to exhibit potential immune-enhancing functions. However, little is known about the in vivo immunomodulatory activity of Korean ginseng berries. In this study, crude Korean ginseng berries polysaccharides (GBP) were isolated and their immunomodulatory activities were investigated using cyclophosphamide (CY)-induced immunosuppressive BALB/c mice. In CY-treated mice, oral administration of GBP (50-500 mg/kg BW) remarkably increased their spleen sizes and spleen indices and activated NK cell activities. GBP also resulted in the proliferation of splenic lymphocytes (coordinating with ConA: plant mitogen which is known to stimulate T-cell or LPS: endotoxin which binds receptor complex in B cells to promote the secretion of pro-inflammatory cytokines) in a dose-dependent manner. In addition, GBP significantly stimulated mRNA expression levels of immune-associated genes including interleukin-1β (IL-1β), IL-2, IL-4, IL-6, tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), toll-like receptor 4 (TLR-4), and cyclooxygenase-2 (COX-2) in CY-treated mice. These results indicate that GBP is involved in immune effects against CY-induced immunosuppression. Thus, GBP could be developed as an immunomodulation agent for medicinal or functional food application.

• 동의생리병리학회지
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• 제25권1호
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• pp.109-114
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• 2011

Atractylodis Rhizoma Alba is commonly used herbal medicine and it has been known that has immuno-regualtory effects and anti-cancer effects. The inhibition of osteoclastogenesis is essential for the prevention and treatment of osteoporosis. The aim of this study was to evaluate the effects of Atractylodis Rhizoma Alba on osteoclast differentiation in vitro and on resorbing activity of osteoclast. Osteoclast formation was evaluated in bone marrow cells (BMC) in the presence or absence of Atractylodis Rhizoma Alba. The expression of c-fos, tartrate-resistant acid phosphatase (TRAP), OSCAR, DC-STAMP, cathepsin K, MafB and NFATc1 mRNA in osteoclast precursor were assessed by RT-PCR. The levels of TNF receptor-associated factor-6 (TRAF-6), c-fos and NFATc1 protein were assessed by Western blot analysis. Also the correlation with MAPKs and NF-${\kappa}B$ pathways were measured by using Western blot analysis. With bone resorption study, I tried to evaluate the inhibitory effects of Atractylodis Rhizoma Alba on mature osteoclast function. Atractylodis Rhizoma Alba inhibited the RANKL induced osteoclastic differentiation from bone marrow macrophage in a dose dependant manner without cellular toxicity. Gene expression of c-fos and NFATc1 was significantly down regulated with Atractylodis Rhizoma Alba treatment. Atractylodis Rhizoma Alba markedly inhibited the RANKL-induced osteoclastogenesis through suppression of nuclear factor kappa b (NF-${\kappa}B$) pathway, down stream pathway of p38, ERK and JNK pathway. Taken together, I concluded that Atractylodis Rhizoma Alba have beneficial effect on osteoporosis by inhibition of osteoclast differentiation and by inhibition of functioning osteoclast. Thus I expect that Atractylodis Rhizoma Alba could be a treatment option for osteoporosis.

• IMMUNE NETWORK
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• 제21권5호
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• pp.37.1-37.17
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• 2021

Hepatitis B virus X (HBx) protein has been reported as a key protein regulating the pathogenesis of HBV-induced hepatocellular carcinoma (HCC). Recent evidence has shown that HBx is implicated in the activation of autophagy in hepatic cells. Nevertheless, the precise molecular and cellular mechanism by which HBx induces autophagy is still controversial. Herein, we investigated the molecular and cellular mechanism by which HBx is involved in the TRAF6-BECN1-Bcl-2 signaling for the regulation of autophagy in response to TLR4 stimulation, therefore influencing the HCC progression. HBx interacts with BECN1 (Beclin 1) and inhibits the association of the BECN1-Bcl-2 complex, which is known to prevent the assembly of the pre-autophagosomal structure. Furthermore, HBx enhances the interaction between VPS34 and TRAF6-BECN1 complex, increases the ubiquitination of BECN1, and subsequently enhances autophagy induction in response to LPS stimulation. To verify the functional role of HBx in liver cancer progression, we utilized different HCC cell lines, HepG2, SK-Hep-1, and SNU-761. HBx-expressing HepG2 cells exhibited enhanced cell migration, invasion, and cell mobility in response to LPS stimulation compared to those of control HepG2 cells. These results were consistently observed in HBx-expressed SK-Hep-1 and HBx-expressed SNU-761 cells. Taken together, our findings suggest that HBx positively regulates the induction of autophagy through the inhibition of the BECN1-Bcl-2 complex and enhancement of the TRAF6-BECN1-VPS34 complex, leading to enhance liver cancer migration and invasion.

• Journal of Animal Science and Technology
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• 제53권6호
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• pp.511-516
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• 2011

Fas gene known to associate with intramuscular fat content in Korean cattle was selected for DNA marker development. Fas (APO-1, CD95), a member of the tumor necrosis factor (TNF) receptor superfamily, is a cell membrane protein that mediates apoptosis (programmed cell death). We discovered single nucleotide polymorphisms (SNPs) within Fas gene in order to develop novel DNA markers at genomic level. Of this gene to search for SNP, sequences of whole exon and 1kb range of both front and back of the gene using 24 cattle were determined by direct-sequencing methods. As a result, 16 SNPs in exon, 37 SNPs in intron and 2 SNPs in promoter region, a total of 55 SNPs were discovered. In these SNPs, thirty-one common polymorphic sites were selected considering their allele frequencies, haplotype-tagging status and Linkage Disequilibrium (LD) for genotyping in larger-scale subjects. Selected SNPs were confirmed genotype through SNaPshot method (n=274) and were examined for possible genetic association of Fas polymorphisms with carcass weight (CWT), eye muscle area (EMA), and backfat thickness (BF). So, the SNP have been identified significant g.-12T>G, g.1112T>G and g.32548T>C. These results suggest that polymorphism of Fas gene was associated with meat quality traits in Hanwoo.

• Molecules and Cells
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• 제44권12호
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• pp.893-899
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• 2021

BLT2 is a low-affinity receptor for leukotriene B₄, a potent lipid mediator of inflammation generated from arachidonic acid via the 5-lipoxygenase pathway. The aim of this study was to investigate whether BLT2 plays any role in sepsis, a systemic inflammatory response syndrome caused by infection. A murine model of cecal ligation and puncture (CLP)-induced sepsis was used to evaluate the role of BLT2 in septic inflammation. In the present study, we observed that the levels of ligands for BLT2 (LTB₄ [leukotriene B₄] and 12(S)-HETE [12(S)-hydroxyeicosatetraenoic acid]) were significantly increased in the peritoneal lavage fluid and serum from mice with CLP-induced sepsis. We also observed that the levels of BLT2 as well as 5-lipoxygenase (5-LO) and 12-LO, which are synthesizing enzymes for LTB₄ and 12(S)-HETE, were significantly increased in lung and liver tissues in the CLP mouse model. Blockade of BLT2 markedly suppressed the production of sepsis-associated cytokines (IL-6 [interleukin-6], TNF-α [tumor necrosis factor alpha], and IL-1β [interleukin-β] as well as IL-17 [interleukin-17]) and alleviated lung inflammation in the CLP group. Taken together, our results suggest that BLT2 cascade contributes to lung inflammation in CLP-induced sepsis by mediating the production of inflammatory cytokines. These findings suggest that BLT2 may be a potential therapeutic target for sepsis patients.