• Title/Summary/Keyword: TLR9

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Anti-Endotoxin 9-Meric Peptide with Therapeutic Potential for the Treatment of Endotoxemia

  • Krishnan, Manigandan;Choi, Joonhyeok;Choi, Sungjae;Kim, Yangmee
    • Journal of Microbiology and Biotechnology
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    • v.31 no.1
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    • pp.25-32
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    • 2021
  • Inflammatory reactions activated by lipopolysaccharide (LPS) of gram-negative bacteria can lead to severe septic shock. With the recent emergence of multidrug-resistant gram-negative bacteria and a lack of efficient ways to treat resulting infections, there is a need to develop novel anti-endotoxin agents. Antimicrobial peptides have been noticed as potential therapeutic molecules for bacterial infection and as candidates for new antibiotic drugs. We previously designed the 9-meric antimicrobial peptide Pro9-3 and it showed high antimicrobial activity against gram-negative bacteria. Here, to further examine its potency as an anti-endotoxin agent, we examined the anti-endotoxin activities of Pro9-3 and elucidated its mechanism of action. We performed a dye-leakage experiment and BODIPY-TR cadaverine and limulus amebocyte lysate assays for Pro9-3 as well as its lysine-substituted analogue and their enantiomers. The results confirmed that Pro9-3 targets the bacterial membrane and the arginine residues play key roles in its antimicrobial activity. Pro9-3 showed excellent LPS-neutralizing activity and LPS-binding properties, which were superior to those of other peptides. Saturation transfer difference-nuclear magnetic resonance experiments to explore the interaction between LPS and Pro9-3 revealed that Trp3 and Tlr7 in Pro9-3 are critical for attracting Pro9-3 to the LPS in the gram-negative bacterial membrane. Moreover, the anti-septic effect of Pro9-3 in vivo was investigated using an LPS-induced endotoxemia mouse model, demonstrating its dual activities: antibacterial activity against gram-negative bacteria and immunosuppressive effect preventing LPS-induced endotoxemia. Collectively, these results confirmed the therapeutic potential of Pro9-3 against infection of gram-negative bacteria.

Inhibitory Effect of S100A8 on Neutrophil Apoptosis by Cytokine Release of Normal and Allergic Monocytes

  • Lee, Ji-Sook
    • Biomedical Science Letters
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    • v.26 no.3
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    • pp.226-229
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    • 2020
  • S100A8 functions as an essential factor in inflammatory response. Cytokine release of monocytes and regulation of neutrophil apoptosis are important steps in pathogenesis of allergy. This study aims to examine the relation between cytokine release of monocytes due to S100A8 and neutrophil apoptosis. S100A8 enhanced the release of IL-6 and IL-8 in monocytes of normal and allergic subjects. Treatment of supernatants of normal and allergic monocytes with S100A8 blocked neutrophil apoptosis by inhibition of caspase 9 and caspase 3 activation. The secretion signal induced by S100A8 is involved in TLR4, Src family protein, PKCδ, ERK1/2, p38 MAPK, JNK, and NF-κB. These findings may contribute to understanding the complex pathogenesis of allergic diseases by determining inflammatory responses associated with S100A8, monocytes, and neutrophils.

Toll-like Receptor 5 Agonism Protects Mice from Radiation Pneumonitis and Pulmonary Fibrosis

  • Wang, Zhi-Dong;Qiao, Yu-Lei;Tian, Xi-Feng;Zhang, Xue-Qing;Zhou, Shi-Xiang;Liu, Hai-Xiang;Chen, Ying
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.9
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    • pp.4763-4767
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    • 2012
  • Radiation pneumonitis and pulmonary fibrosis are the main complications with radiotherapy for thoracic neoplasms, directly limiting the efficient dose in clinical application and currently there are few medicines that effectively function as radioprotectants. However, a TLR5 agonist, CBLB502, was confirmed to have protective efficacy against hematopoietic and gastrointestinal radiation syndromes in mice and primates. This study points to a new direction for protection against thoracic radiation-induced pulmonary syndromes and skin injury by CBLB502. We utilized the TUNEL assay, pathological analysis and immunohistochemistry to obtain evidence thatCBLB502 could alleviate the occurrence of radiation pneumonitis and pulmonary fibrosis as well as radiation-induced skin injury. It may thus play a promising role in facilitating clinical radiotherapy of thoracic neoplasms.

Vibrio Vulnificus Induces the Inflammation of Mouse Ileal Epithelium: Involvement of Protein Kinase C and Nuclear Factor-Kappa B (회장 상피세포에서 비브리오균(Vibrio vulnificus)의 염증 유도 기작 연구: protein kinase C와 nuclear factor kappa-B의 관련성)

  • Han, Gi Yeon;Jung, Young Hyun;Jang, Kyung Ku;Choi, Sang Ho;Lee, Sei-Jung
    • Journal of Life Science
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    • v.24 no.6
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    • pp.664-670
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    • 2014
  • In the present study, we investigate the role of V. vulnificus in promoting the inflammation of mouse ileal ephitelium and its related signaling pathways. ICR mice were infected orally with V. vulnificus ($1{\times}10^9CFU$) for 16 h as a representative model of food-borne infection. To find the major portal of entry of V. vulnificus in mouse intestine, we have measured the levels of bacterial colonization in small intestine, colon, spleen, and liver. V. vulnificus appeared to colonize in intestine and colon in the order of ileum >> jejunum> colon, but lack in the duodenum, spleen, and liver. V. vulnificus in ileum caused severe necrotizing enteritis and showed shortened villi heights accompanied by an expanded width and inflammation, compared with the control mice. V. vulnificus induced ileal epithelium inflammation by activating phosphorylation of PKC and membrane translocation of $PKC{\alpha}$. V. vulnificus induced the phosphorylation of ERK and JNK, but did not affect p38 MAPK phosphorylation. Notably, V. vulnificus stimulated the I-${\kappa}B$-dependent phosphorylation of NF-${\kappa}B$ in mouse ileal epithelium. Finally, the ileal infection of V. vulnificus resulted in a significant increase in expression of proinflammatory cytokines and Toll-like receptors, respectively, compared to the control. Collectively, our results indicate that V. vulnificus induces ileal epithelium inflammation by increasing NF-${\kappa}B$ phosphorylation via activation of PKC, ERK, and JNK, which is critical for host defense mechanism in food-borne infection by V. vulnificus.

Mycobacterium abscessus MAB2560 induces maturation of dendritic cells via Toll-like receptor 4 and drives Th1 immune response

  • Lee, Su Jung;Shin, Sung Jae;Lee, Seung Jun;Lee, Moon Hee;Kang, Tae Heung;Noh, Kyung Tae;Shin, Yong Kyoo;Kim, Han Wool;Yun, Cheol-Heui;Jung, In Duk;Park, Yeong-Min
    • BMB Reports
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    • v.47 no.9
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    • pp.512-517
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    • 2014
  • In this study, we showed that Mycobacterium abscessus MAB2560 induces the maturation of dendritic cells (DCs), which are representative antigen-presenting cells (APCs). M. abscessus MAB2560 stimulate the production of pro-inflammatory cytokines [interleukin (IL)-6, tumor necrosis factor (TNF)-${\alpha}$, IL-$1{\beta}$, and IL-12p70] and reduce the endocytic capacity and maturation of DCs. Using $TLR4^{-/-}$ DCs, we found that MAB2560 mediated DC maturation via Toll-like receptor 4 (TLR4). MAB2560 also activated the MAPK signaling pathway, which was essential for DC maturation. Furthermore, MAB2560-treated DCs induced the transformation of $na\ddot{i}ve$ T cells to polarized $CD4^+$ and $CD8^+$ T cells, which would be crucial for Th1 polarization of the immune response. Taken together, our results indicate that MAB2560 could potentially regulate the host immune response to M. abscessus and may have critical implications for the manipulation of DC functions for developing DC-based immunotherapy.

Allergy Immunity Regulation and Synergism of Bifidobacteria (Bifidobacteria의 allergy 면역 조절과 synergism)

  • Cho, Kwang Keun;Choi, In Soon
    • Journal of Life Science
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    • v.27 no.4
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    • pp.482-499
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    • 2017
  • Allergic diseases have increased over the past several decade worldwide including developing countries. Allergic inflammatory responses are caused by Th (T helper)2 immune responses, triggered by allergen ingestion by antigen presenting cells such as dendritic cells (DCs). Intestinal microorganisms control the metabolism and physiological functions of the host, contribute to early immune system maturation during the early life, and homeostasis and epithelial integrity during life. Bifidobacteria have strain-specific immunostimulatory properties in the Th1/Th2 balance, inhibit TSLP (thymic stromal lymphopoietin) and IgE expression, and promote Flg (Filaggrin) and FoxP3 (Treg) expression to alleviate allergies. In addition, unmethylated CpG motif ODN (oligodeoxynucleotides) is recognized by TLR (toll-like receptors)9 of B cells and plasmacytoid dendritic cells (pDCs) to induce innate and adaptive immune responses, while the butyrate produced by Clostridium butyricum activates the GPR (G-protein coupled receptors)109a signaling pathway to induce the expression of anti-inflammatory gene of pDCs, and directly stimulates the proliferation of thymically derived regulatory T (tTreg) cells through the activation of GPR43 or inhibits the activity of HADC (histone deacetylase) to differentiate naive $CD4^+$ T cells into pTreg cells through the histone H3 acetylation of Foxp3 gene intronic enhancer.

Comparison of Efficacy of Overlapped Versus Long Eluting Stent in Acute Myocardial Infarction Patients with Diffuse Long Lesion (미만성 긴 병변이 있는 급성심근경색환자에서 긴 단일 용출 스텐트 시술과 중첩 스텐트 시술의 효과 비교)

  • Kim, Won Hyo;Kim, In Soo;Kong, Chang gi;Han, Jae Bok
    • Journal of the Korean Society of Radiology
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    • v.14 no.3
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    • pp.319-336
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    • 2020
  • The purpose of this study was to compare the outcomes of two interventional methods, overlapping drug-eluting stents (DES) and long DES, for long-term clinical outcomes in patients with acute myocardial infarction (AMI). A total of 438 patients with AMI (65.9±11.0 years, 306 males) from June 2008 to March 2019 who had diffuse long coronary artery lesion, more than 30mm were divided into two groups; group I (overlapped DES group; n=140) and group II (long DES group; n=298). We compared the incidences of major adverse cardiac events [MACEs; cardiac death, myocardial infaction (MI), target lesion revascularization (TLR) and stent thrombosis (ST)] during 12 months between the two groups. Everolimus-eluting stent was more commonly used in group II than in group I (28.1% vs. 51.8% p<0.001). Mean lesion diameter was slightly longer in group II (3.1±0.3mm vs. 3.2±0.3mm, p=0.042), and prevalence of ACC/AHA lesion type C was higher in group I (41.7% vs. 25.4%, p<0.001). Incidences of MACEs during 12 months were higher in group I than group II (18.5% vs. 14.4%, p=0.034). The rates of cardiac death (2.1% vs. 4.4%, p=0.667), MI (5.0% vs. 2.7%, p=0.260) and stent thrombosis rate (0.7% vs. 1.7%, p=0.669) were similar between the two groups. However, TLR rate was higher in group I (10.7% vs. 5.6%, p=0.041). In multivariate logistic regression analysis, presence of diabetes mellitus [Hazard ratio (HR) 2.383, 95% confidence interval (CI) 1.332-4.260, p=0.003] and use of paclitaxel-eluting stent (HR) 2.367, 95% CI 1.371-4.086, p=0.002) were independent predictors of 12-month MACEs, without significant differences in prevalence between the two groups. In AMI patients with diffuse long lesion, TLR rate was higher in the overlapped DES group during 12-month follow-up. Presence of diabetes and use of paclitaxel-eluting stent were independent predictors of MACEs.

Effects of bacterial LPS and DNA on the induction of IL-1β, IL-10 and IL-12 by mouse peritoneal macrophages in vitro

  • Samad, D. Abdel;Abdelnoor, AM
    • Advances in Traditional Medicine
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    • v.6 no.2
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    • pp.134-143
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    • 2006
  • The capacities of bacterial DNA, extracted from Salmonella typhimurium, and lipopolysaccharide (LPS), extracted from Salmonella minnesota, to activate mouse peritoneal macrophages in vitro were compared. Activation was assessed by estimating e levels of 3 cytokines, IL-10, IL-12, and $IL-1{\beta}$, at time intervals of 3, 6, 9, and 24 h after addition of LPS and/or DNA to macrophage cultures. Cytokine levels in culture supernatants were determined by enzyme-linked immunosorbent assay (ELISA) and cytokine mRNA levels were estimated based on band intensity in cultured cells by reverse transcriptase-polymerase chain reaction (RT-PCR). Results obtained demonstrated the ability of DNA and LPS to elicit increased production of all 3 cytokines as compared to controls. In the amount tested, LPS appeared to be a more potent inducer of IL-12, and $IL-1{\beta}$, whereas DNA induced higher levels of IL-10. DNA and LPS, used in combination, exhibited neither an additive nor a synergistic effect. Rather, an antagonist effect appeared to occur. RT-PCR results correlated well with ELISA.

Anti-Inflammatory and Anti-allergic Effects of Gnaphalium affine Extract (떡쑥 추출물의 항염증 및 항알러지 효과)

  • Roh, Kyung-Baeg;Lee, Jung-A;Park, Junho;Jung, Kwangseon;Jung, Eunsun;Park, Deokhoon
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.43 no.2
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    • pp.103-114
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    • 2017
  • Gnaphalium affine D. DON (GA) has been used as a vegetable as well as a folk medicine in East Asia. The antioxidant and anti-complementary activity of GA extract (GAE) has also been reported. However, little is known about its anti-inflammatory and anti-allergic effect and mechanism of action. In this study, we evaluated the inhibitory effects of GAE on the production of inflammatory mediators such as NO, $PGE_2$, TLR4, eotaxin-1 and histamine. Our results suggest that GAE inhibits the production of NO and $PGE_2$ by inhibiting transcriptional activation via the involvement of iNOS and COX-2. The LPS-induced expression of Toll-like receptor 4 (TLR4) was also attenuated. In addition, GAE inhibited A23187-induced histamine release from MC/9 mast cells. It also inhibited the production of eotaxin-1 induced by IL-4. Collectively, these results suggest that GAE may have considerable potential as a cosmetic ingredient with anti-inflammatory and anti-allergic properties.

Prognostic Significance of Basic Laboratory Methods in Non-Small-Cell-Lung Cancer

  • Kaya, Vildan;Yildirim, Mustafa;Demirpence, Ozlem;Yildiz, Mustafa;Yalcin, Aysen Yesim
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.9
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    • pp.5473-5476
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    • 2013
  • Background: In our study, the LDH, albumin, hemoglobin, neutrophile, thrombocyte, lymphocyte counts and prognostic significance of neutrophile-lymphocyte and thrombocyte-lymphocyte ratios in NSCLC derived from these counts obtained during regular examinations of patients were examined. Materials and Methods: Histopathologically diagnosed non-small-cell-lung cancer patients between 2008 and 2010 were included in the study. Before the treatment, full blood count including routine lymphocyte count, blood biochemistry examinations including liver (AST, ALT, total protein, Albumin), LDH and kidney (BUN, Cre) function tests were performed. Results: A total of 156 patients, 76 of whom (48.7%) were female and 80 of whom (51.3%) were male were included. Mean hemoglobin level was determined as 12. Overall survival was found to be significantly dependent on whether patients were anemic or not (p: 0.005). Mean LDH level was determined as 233.4. There was nosurvival difference between patients with and without high LDH (p: 0.532). In patients where NLR showed systemic inflammatory response, overall survival was 10.8 months whereas this duration was 19.6 months in patients where the systemic inflammatory response was negative (p: 0.012). In patients where TLR showed systemic inflammatory response, overall survival was 13.6 months whereas this duration was 21.9 months in patients where the systemic inflammatory response was negative (p: 0.04). Conclusions: Molecular methods have been changing rapidly in today's world and they manage the treatment besides defining the prognosis of patients. However, easily accessible and cheap laboratory parameters should be considered in the prognosis of patients besides these new methods.