Abstract Inflammation is an important event in the development of vascular diseases such as hypertension, atherosclerosis, and restenosis. In addition, the stimulation of Toll-like receptor 4 (TLR4) ...by lipopolysaccharide (LPS) induces the release of critical proinflammatory cytokines that activate potent immune responses. In this study, LPS was found to induce TLR4 expression and increased nitric oxide (NO) production by increasing the expression of inducible nitric oxide synthase (iNOS). Furthermore, LPS was found to induce interleukin (IL)-8 and vascular endothelial growth factor (VEGF) production, as well as intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) expression. Taken together, these results indicate that LPS induces inflammatory responses in HASMC. Moreover, NOS inhibitor (L-NAME) and anti-TLR 4 mAb reduced the LPS-induced NO, IL-8 and VEGF production and ICAM-1 expression. Additionally, TLR4 expression was reduced by NOS inhibitor. Taken together, these results indicate that LPS-induced inflammatory responses are regulated by TLR4 expression and NO production.
Draconis
Resina (DR) is a type of dragon’s blood resin obtained from
Daemomorops
draco BL. (Palmae). DR has long been used as a traditional Korean herbal medicine, and is currently used in ...traditional clinics to treat wounds, tumors, diarrhea, and rheumatism, insect bites and other conditions. In this study, we evaluated fractionated extracts of DR to determine if they inhibited the production of interleukin-1β (IL-1β) and the expression of cyclooxygenase (COX)-2. The results of this analysis revealed that the ethylacetate extract of
Draconis
Resina (DREA) was more potent than that of other extracts. Moreover, DREA inhibited the production of nitric oxide (NO), reactive oxygen species (ROS), prostaglandin E
2 (PGE
2), tumor necrosis factor-α (TNF-α), IL-8 and IL-6 in lipopolysaccharide (LPS)-treated human aortic smooth muscle cells (HASMC) and RAW 264.7 macrophages. Furthermore, treatment with an NADPH oxidase assembly inhibitor, AEBSF, efficiently blocked LPS-induced mitogen-activated protein kinases (MAPKs) activation, as did DREA. These findings indicate that DREA inhibits the production of NO, PGE
2, TNF-α, IL-8, and IL-6 by LPS via the inhibition of ROS production, which demonstrates that DREA inhibits LPS-induced inflammatory responses via the suppression of ROS production. Taken together, these results indicate that DREA has the potential for use as an anti-atherosclerosis agent.
The tumor necrosis factor receptor family molecule 4-1BB (CD137) has diverse roles in adaptive and innate immune responses. However, little is known of its role in bacterial infections. Previously, ...we showed that 4-1BB-deficient mice have enhanced susceptibility to Listeria monocytogenes infection, and mice pretreated with agonistic anti-4-1BB antibody (3E1) were much more resistant to L. monocytogenes infection than mice treated with control antibody. In this study, we report that stimulating 4-1BB by administering 3E1 in the early phase of L. monocytogenes infection is critical for promoting the survival of mice by inducing rapid infiltration of neutrophils and monocytes into L. monocytogenes-infected livers. The levels of tumor necrosis factor alpha, interleukin 6, and monocyte chemoattractant protein 1 in the livers of 3E1-treated mice increased as early as 30 min postinfection and peaked by 1 to 2 h, while those in mice treated with control antibody started to increase only at 16 h postinfection. Monocytes and neutrophils from the 3E1-treated mice had higher levels of activation markers, phagocytic activity, and reactive oxygen species than those from control mice. In vitro stimulation of 4-1BB induced the production of the inflammatory cytokines/chemokines of neutrophils, but not those of monocytes. These results suggest that 4-1BB stimulation of neutrophils in the early phase of L. monocytogenes infection causes rapid production of inflammatory cytokines/chemokines and that the subsequent infiltration of neutrophils and monocytes is crucial for eliminating the infecting L. monocytogenes.
Vascular smooth-muscle cell proliferation plays an important role in atherosclerosis and restenosis. Rhein is an active component extracted from rhubarb. In this study, rhein was found to exert ...potent inhibitory effects against tumor necrosis factor (TNF)-alpha-induced human aortic smooth-muscle cells (HASMCs) proliferation.
These effects were associated with induced apoptosis, including the induction of Annexin V-positive cells, the cleavage of poly(ADP-ribose)polymerase (PARP), and caspases 3, 8 and 9.
Inhibitors of caspases 3, 8 and 9 were efficiently blocked by rhein-induced apoptosis in TNF-alpha-treated HASMCs. In addition, treatment with rhein resulted in the release of cytochrome c into the cytosol, a loss of mitochondrial membrane potential (DeltaPsi(m)), a decrease in Bcl-2 and Bcl-xL and an increase in Bax and Bak expression. However, rhein-mediated apoptosis was blocked by a mitochondrial membrane depolarization inhibitor. These findings indicate that rhein-induced apoptosis occurred via a mitochondrial pathway. Furthermore, the inhibition of mitochondrial membrane depolarization was efficiently blocked by rhein-induced caspase-9 activity, which indicates that the rhein-induced caspase activation signal was downstream of the mitochondrial pathway. Taken together, the results of this study show that rhein inhibits TNF-alpha-induced HASMC proliferation via mitochondria-dependent apoptosis and that rhein has the potential to act as an anti-atherosclerosis agent.
The development of gastric cancer (GC) is closely related to chronic inflammation caused by Helicobacter pylori infection, and herpes virus entry mediator (HVEM) is a receptor expressed on the ...surface of leukocytes that mediates potent inflammatory responses in animal models. However, the role of HVEM in human GC has not been studied. Previously, we showed that the interaction of HVEM on human leukocytes with its ligand LIGHT induces intracellular calcium mobilization, which results in inflammatory responses including induction of proinflammatory cytokine production and anti-bacterial activities. In this study, we report that leukocytes from GC patients express lower levels of membrane HVEM (mHVEM) and have lower LIGHT-induced bactericidal activities than those from healthy controls (HC). In contrast, levels of soluble HVEM (sHVEM) in the sera of GC patients were significantly higher than in those of HC. We found that monocyte membrane-bound HVEM is released into the medium when cells are activated by proinflammatory cytokines such as TNF-α and IL-8, which are elevated in the sera of GC patients. mHVEM level dropped in parallel with the release of sHVEM, and release was completely blocked by the metalloprotease inhibitor, GM6001. We also found that the low level of mHVEM on GC patient leukocytes was correlated with low LIGHT-induced bactericidal activities against H. pylori and S. aureus and production of reactive oxygen species. Our results indicate that mHVEM on leukocytes and sHVEM in sera may contribute to the development and/or progression of GC.
4‐1BB costimulates T cells to carry out effector functions such as eradication of established tumours. 4‐1BB (CD137) is a member of the TNF receptor family, and its triggering by either 4‐1BB ligand ...or antibody ligation induces T‐cell activation and growth. We analysed tumour‐infiltrating lymphocytes (TIL) in the experimental B16F10 melanoma model to determine the mechanisms involved in 4‐1BB‐mediated tumour suppression. 4‐1BB+/+ mice survived longer than 4‐1BB–/– mice, and survival was further prolonged by triggering 4‐1BB with an agonistic mAb. The number of metastatic B16F10 colonies in the lung was much greater in 4‐1BB–/– mice than in their 4‐1BB+/+ littermates. Administration of agonistic anti‐4‐1BB mAb increased the number of TIL in the tumour masses in the lungs of 4‐1BB+/+ mice. The numbers of CD4+ T, CD8+ T and CD11b+ TIL increased in these mice. Anti‐4‐1BB mAb induced not only CD8+ 4‐1BB+ T cells but also a CD8+ IFN‐γ+ T‐cell population. B16F10 cells from the lungs of anti‐4‐1BB‐treated mice showed enhanced expression of MHC class Ι and II antigens compared with the same cells from control IgG‐treated mice. Thus, the increase in number of CD8+ T cells and enhanced MHC Ι and II expression in B16F10 cells that result from augmented IFN‐γ production in response to anti‐4‐1BB mAb may lead to suppression of tumour growth and metastasis.
LIGHT Heo, Sook-Kyoung; Yu, Ho-Min; Kim, Do Kyoung ...
PloS one,
08/2023, Letnik:
18, Številka:
8
Journal Article
Recenzirano
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
28.
LIGHT Heo, Sook-Kyoung; Yu, Ho-Min; Kim, Do Kyoung ...
PloS one,
08/2023, Letnik:
18, Številka:
8
Journal Article
Recenzirano
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
29.
LIGHT Jo, Jae-Cheol; Seo, Hye Jin; Lee, Yoo Jin ...
PloS one,
08/2023, Letnik:
18, Številka:
8
Journal Article
Recenzirano
Liver transplantation is the most effective treatment option for patients with acute or chronic liver failure. However, the applicability and effectiveness of this modality are often limited by a ...shortage of donors, surgical complications, high medical costs, and the need for continuing immunosuppressive therapy. An alternative approach is liver cell transplantation. LIGHT (a member of the tumor necrosis factor superfamily) could be a promising candidate for promoting the differentiation of human bone marrow-derived mesenchymal stem cells (hBM-MSCs) into hepatocyte-like cells. In this study, we investigated the effect of LIGHT on hBM-MSC differentiation into hepatocyte-like cells. Our previous results showed that LIGHT receptor lymphotoxin-beta receptor (LTbetaR) is constitutively expressed on the surface of hBM-MSCs. Upon treatment with recombinant human LIGHT (rhLIGHT), the phenotype of hBM-MSCs changed to round or polygonal cells. In addition, the cells exhibited high levels of hepatocyte-specific markers, including albumin, cytokeratin-18 (CK-18), CK-19, cytochrome P450 family 1 subfamily A member 1 (CYP1A1), CYP1A2, CYP3A4, SRY-box transcription factor 17 (SOX17), and forkhead box A2 (FOXA2). These results indicate that rhLIGHT enhances the differentiation of hBM-MSCs into functional hepatocyte-like cells. Furthermore, rhLIGHT-induced hepatocyte-like cells showed a higher ability to store glycogen and uptake indocyanine green compared with control cells, indicating functional progression. Additionally, treatment with rhLIGHT increased the number, viability, and proliferation of cells by inducing the S/G2/M phase and upregulating the expression of various cyclin and cyclin dependent kinase (CDK) proteins. We also found that the hepatogenic differentiation of hBM-MSCs induced by rhLIGHT was mediated by the activation of signal transducer and activator of transcription 3 (STAT3) and STAT5 pathways. Overall, our findings suggest that LIGHT plays an essential role in promoting the hepatogenic differentiation of hBM-MSCs. Hence, LIGHT may be a valuable factor for stem cell therapy.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Homologous to lymphotoxins, shows inducible expression, and competes with herpes simplex virus (HSV) glycoprotein D (gD) for herpes virus entry mediator (HVEM; TR2) (LIGHT), a ligand of herpes virus ...entry mediator (HVEM), increased reactive oxygen species (ROS) and enhanced the destruction of bacteria in human monocytes. In this study, rhLIGHT was found to increase the expression of the chemokine receptors, chemokine receptor 1 (CCR1) and CCR2, as well as to accelerate the migration activity of human monocytes. Additionally, rhLIGHT was found to increase ROS via NADPH oxidase p47
phox
phosphorylation, which was found to be required for LIGHT-induced NF-κB activation, CCR1 and CCR2 expression, migration and IL-8 and TNF-α production. Taken together, these results indicate that NADPH oxidase activation is required for rhLIGHT-induced migration in human monocytes.
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