scholarly journals Zymosan-a Protects the Hematopoietic System from Radiation-Induced Damage by Targeting TLR2 Signaling Pathway

2017 ◽  
Vol 43 (2) ◽  
pp. 457-464 ◽  
Author(s):  
Jicong Du ◽  
Ying Cheng ◽  
Suhe Dong ◽  
Pei Zhang ◽  
Jiaming Guo ◽  
...  

Background/Aims: The hematopoietic system is vulnerable to ionizing radiation and is often severely damaged by radiation. Molecules affecting radioresistance include Toll-like receptor 2. We investigated whether Zymosan-A, a novel TLR2 agonist, can protect the hematopoietic system from radiation-induced damage after total body irradiation. Methods: Mice were exposed to total body radiation after treatment with Zymosan-A or normal saline, and their survival was recorded. Tissue damage was evaluated by hematoxylin–eosin staining. The number of nucleated cells in bone marrow was determined by flow cytometry. Cell viability and apoptosis assay were determined by CCK-8 assay and flow cytometry assay. Enzyme-linked immunosorbent assay was used to detect the level of cytokines. Results: Zymosan-A protected mice from radiation-induced death and prevented radiation-induced hematopoietic system damage. Zymosan-A also promoted cell viability and inhibited cell apoptosis caused by radiation, induced radioprotective effects via TLR2, upregulated IL-6, IL-11, IL-12, and TNF-α in vivo. Conclusion: Zymosan-A can provide protection against radiation-induced hematopoietic system damage by targeting the TLR2 signaling pathway. Thus, Zymosan-A can be potentially effective radioprotectant.

2021 ◽  
Vol 22 (4) ◽  
pp. 2141
Author(s):  
Srinu Tumpara ◽  
Elena Korenbaum ◽  
Mark Kühnel ◽  
Danny Jonigk ◽  
Beata Olejnicka ◽  
...  

The C-terminal-fragments of alpha1-antitrypsin (AAT) have been identified and their diverse biological roles have been reported in vitro and in vivo. These findings prompted us to develop a monoclonal antibody that specifically recognizes C-36 peptide (corresponding to residues 359–394) resulting from the protease-associated cleavage of AAT. The C-36-targeting mouse monoclonal Immunoglobulin M (IgM) antibody (containing κ light chains, clone C42) was generated and enzyme-linked immunosorbent assay (ELISA)-tested by Davids Biotechnologie GmbH, Germany. Here, we addressed the effectiveness of the novel C42 antibody in different immunoassay formats, such as dot- and Western blotting, confocal laser microscopy, and flow cytometry. According to the dot-blot results, our novel C42 antibody detects the C-36 peptide at a range of 0.1–0.05 µg and shows no cross-reactivity with native, polymerized, or oxidized forms of full-length AAT, the AAT-elastase complex mixture, as well as with shorter C-terminal fragments of AAT. However, the C42 antibody does not detect denatured peptide in SDS-PAGE/Western blotting assays. On the other hand, our C42 antibody, unconjugated as well as conjugated to DyLight488 fluorophore, when applied for immunofluorescence microscopy and flow cytometry assays, specifically detected the C-36 peptide in human blood cells. Altogether, we demonstrate that our novel C42 antibody successfully recognizes the C-36 peptide of AAT in a number of immunoassays and has potential to become an important tool in AAT-related studies.


2021 ◽  
Author(s):  
Wei Hu ◽  
Jiawu Liang ◽  
Song Liao ◽  
Zhidong Zhao ◽  
Yuxing Wang ◽  
...  

Abstract Background Ionizing radiation poses a challenge to the healing of bone defects. Radiation therapy and accidental exposure to gamma-ray (γ-ray) radiation inhibit bone formation and increase the risk of fractures. Cortical bone-derived stem cells (CBSCs) are essential for osteogenic lineages, bone maintenance, and repair. This study aimed to investigate the effects of melatonin on postradiation CBSCs and bone defects. Methods CBSCs were extracted from C57/BL6 mice and were identified by flow cytometry. The effects of exogenous melatonin on the self-renewal and osteogenic capacity of postradiation CBSCs were detected in vitro. The underlying mechanisms in terms of genomic stability, apoptosis and oxidative stress-related signaling were further analyzed by western blotting, flow cytometry and immunofluorescence. Finally, the effects of melatonin on healing in postradiation bone defects were evaluated in vivo by micro-CT and immunohistochemical analysis. Results The radiation-induced reduced self-renewal and osteogenic capacity were partially reversed in postradiation CBSCs treated with melatonin. Melatonin maintained the genomic stability and apoptosis of postradiation CBSCs, and intracellular oxidative stress was decreased significantly while antioxidant-related enzymes were enhanced. Western blotting verified the anti-inflammatory effect of melatonin by downregulating the levels of IL-6 and TNF-α via extracellular regulated kinase (ERK)/nuclear factor erythroid 2-related factor 2 (NRF2)/heme oxygenase 1 (HO-1) signaling, distinct from its antioxidant effect via NRF2 signaling. In vivo experiments demonstrated that the newly formed bone in the melatonin plus Matrigel group had higher trabecular bone volume per tissue volume (BV/TV) and bone mineral density (BMD) values, and lower levels of IL-6 and TNF-α than those in the irradiation and the Matrigel groups. Conclusions This study suggested the potential of melatonin to protect CBSCs against γ-ray radiation and to assist the healing of postradiation bone defects.


2021 ◽  
Vol 21 ◽  
Author(s):  
Zhen Zhao ◽  
Yu Lu ◽  
Huan Wang ◽  
Xiang Gu ◽  
Luting Zhu ◽  
...  

Background: Some studies demonstrated that under high-glucose (HG) condition, osteoblasts develop oxidative stress, which will impair their normal functions. The effects of activin receptor-like kinase 7 (ALK7) silencing on HG-induced osteoblasts remained unclear. Objective: The aim of this study was to explore the effect of ALK7 on HG-induced osteoblasts. Methods: MC3T3-E1 cells were treated with different concentrations of HG (0, 50, 100, 200 and 300mg/dL), and the cell viability was detected using cell counting kit-8 (CCK-8). HG-treated MC3T3-E1 cells were transfected with siALK7 or ALK7 overexpression plasmid or siNrf2, and then the viability and apoptosis were detected by CCK-8 and flow cytometry. The levels of reactive oxygen species (ROS), collagen I and calcification nodule were determined by oxidative stress kits, Enzyme-linked immunosorbent assay and Alizarin red staining. The expressions of NF-E2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1) and osteoblast-associated genes were determined by quantitative real-time PCR (qRT-PCR) and Western blot. Results: Cell viability was reduced with HG treatment. Silencing ALK7 inhibited the effect of HG on increasing cell apoptosis and ROS production, reduced cell viability, mineralized nodules, and downregulated collagen I and osteoblast-associated genes expression in MC3T3-E1 cells. ALK7 silencing activated the Nrf2/HO-1 signaling pathway by affecting expressions of HO-1 and Nrf2. ALK7 overexpression had the opposite effects. In addition, siNrf2 partially reversed the effects of ALK7 silencing on HG-induced MC3T3-E1 cells. Conclusion: ALK7 silencing protected osteoblasts under HG condition possibly through activating the Nrf2/HO-1 pathway.


Blood ◽  
2000 ◽  
Vol 95 (3) ◽  
pp. 837-845 ◽  
Author(s):  
Thomas J. MacVittie ◽  
Ann M. Farese ◽  
Walter G. Smith ◽  
Charles M. Baum ◽  
Earl Burton ◽  
...  

Myelopoietins (MPOs) constitute a family of engineered, chimeric molecules that bind and activate the IL-3 and G-CSF receptors on hematopoietic cells. This study investigated the in vivo hematopoietic response of rhesus monkeys administered MPO after radiation-induced myelosuppression. Animals were total body irradiated (TBI) in 2 series, with biologically equivalent doses consisting of either a 700 cGy dose of Cobalt-60 (60Co) γ-radiation or 600 cGy, 250 kVp x-irradiation. First series: On day 1 after 700 cGy irradiation, cohorts of animals were subcutaneously (SC) administered MPO at 200 μg/kg/d (n = 4), or 50 μg/kg/d (n = 2), twice daily, or human serum albumin (HSA) (n = 10). Second series: The 600 cGy x-irradiated cohorts of animals were administered either MPO at 200 μg/kg/d, in a daily schedule (n = 4) or 0.1% autologous serum (AS) , daily, SC (n = 11) for 23 days. MPO regardless of administration schedule (twice a day or every day) significantly reduced the mean durations of neutropenia (absolute neutrophil count [ANC] < 500/μL) and thrombocytopenia (platelet < 20 000/μL) versus respective control-treated cohorts. Mean neutrophil and platelet nadirs were significantly improved and time to recovery for neutrophils (ANC to < 500/μL) and platelets (PLT < 20 000/μL) were significantly enhanced in the MPO-treated cohorts versus controls. Red cell recovery was further improved relative to control-treated cohorts that received whole blood transfusions. Significant increases in bone marrow-derived clonogenic activity was observed by day 14 after TBI in MPO-treated cohorts versus respective time-matched controls. Thus, MPO, administered daily was as effective as a twice daily schedule for multilineage recovery in nonhuman primates after high-dose, radiation-induced myelosuppression.


2017 ◽  
Vol 42 (1) ◽  
pp. 91-102 ◽  
Author(s):  
Xin Xue ◽  
Yi Qiu ◽  
Hong-Li Yang

Background/Aims: The purpose of this study is to explore the immunoregulatory role of microRNA-21 (miR-21) targeting of the TLR4/MyD88 signaling pathway in macrophages in response to Bacillus Calmette-Guerin (BCG) infection. Methods: After infection with BCG, mouse RAW246.7 cells were assigned into control, BCG, miR-21 mimic + BCG, mimic-negative control (NC) + BCG, miR-21 inhibitor + BCG, inhibitor-NC + BCG, BCG + TAK242 (an inhibitor of the TLR4 signaling pathway), and miR-21 inhibitor + TAK242 + BCG groups. Western blotting and qRT-PCR were used to detect the expression of miR-21, TLR4 and MyD88. The levels of TNF-a, IL-6 and IL-10 were detected by enzyme-linked immunosorbent assay (ELISA). Cell viability was measured using an MTT assay. Cell apoptosis and necrosis rates were detected using flow cytometry. Results: Compared with the control group, miR-21 expression and levels of TNF-a, IL-6 and IL-10, as well as cell apoptosis and necrosis rates, were elevated, while expression of TLR4 and MyD88, as well as cell viability, were reduced in BCG infection groups. Compared with the BCG group, miR-21 expression was increased in the miR-21 mimic + BCG group but decreased in the miR-21 inhibitor + BCG and miR-21 inhibitor + TAK242 + BCG groups. The expression of TLR4 and MyD88, as well as the cell viability, were decreased, while levels of TNF-a, IL-6 and IL-10, as well as cell apoptosis and necrosis rates, were increased in the miR-21 mimic + BCG and TAK242 + BCG groups. The opposite trends were found in the miR-21 inhibitor + BCG group. Compared with the TAK242 + BCG group, the miR-21 inhibitor + TAK242 + BCG group had higher expression of TLR4 and MyD88 as well as higher cell viability and lower levels of TNF-a, IL-6, IL-10, cell apoptosis and necrosis rates. However, the miR-21 inhibitor + TAK242 + BCG group exhibited the opposite trends when compared with the miR-21 inhibitor + BCG group. Conclusion: Our results suggest that miR-21 can negatively modulate the TLR4/MyD88 signaling pathway, resulting in decreased cell viability, increased cell apoptosis and increased levels of inflammatory factors following BCG infection in macrophages.


2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Yi Chen ◽  
Chen Liu ◽  
Peng Zhou ◽  
Jiannan Li ◽  
Xiaoxiao Zhao ◽  
...  

Coronary artery no-reflow is a complex problem in the area of reperfusion therapy, and the molecular mechanisms underlying coronary artery no-reflow injury have not been fully elucidated. In the present study, we explored whether oxidative stress caused damage to coronary endothelial cells by inducing mitochondrial fission and activating the JNK pathway. The hypoxia/reoxygenation (H/R) model was induced in vitro to mimic coronary endothelial no-reflow injury, and mitochondrial fission, mitochondrial function, and endothelial cell viability were analyzed using western blotting, quantitative polymerase chain reaction (qPCR), enzyme-linked immunosorbent assay (ELISA), and immunofluorescence. Our data indicated that reactive oxygen species (ROS) were significantly induced upon H/R injury, and this was followed by decreased endothelial cell viability. Mitochondrial fission was induced and mitochondrial bioenergetics were impaired in cardiac endothelial cells after H/R injury. Neutralization of ROS reduced mitochondrial fission and protected mitochondrial function against H/R injury. Our results also demonstrated that ROS stimulated mitochondrial fission via JNK-mediated Drp1 phosphorylation. These findings indicate that the ROS-JNK-Drp1 signaling pathway may be one of the molecular mechanisms underlying endothelial cell damage during H/R injury. Novel treatments for coronary no-reflow injury may involve targeting mitochondrial fission and the JNK-Drp1 signaling pathway.


2020 ◽  
Author(s):  
Yue-zhi Zhang ◽  
Shu-jing Ge ◽  
Qing-zhen Leng ◽  
Jian-jun Ma ◽  
Hanchen Liu

Abstract Background: This study aimed to confirm the cytotoxicity of zymosan in AHH-1 cells and HIECs and to determine the treatment time and dose of zymosan at which it exerts radioprotective effects.Methods: AHH-1 cells and HIECs were administered 0, 20, 40, 80 or 160 μg/mL zymosan. The CCK-8 assay and flow cytometry were used to evaluate cell viability and apoptosis 24 h, 48 h, and 72 h after administration. Furthermore, 12 h before irradiation, the cells were treated with 0, 5, 10, or 20 μg/mL zymosan and then irradiated with 4 Gy X-rays. Cell viability and apoptosis were measured by the CCK-8 assay and flow cytometry at 24 h. In addition, the protective effect of zymosan against radiation in vitro was compared to that of 20 μg/mL LPS as a positive control. In vivo, weight, the spleen index and the thymus index were measured to evaluate the toxicity of 0, 5, 10, 20 and 10 mg/kg zymosan. In addition, rats were treated with 0, 2, 4, 8 or 10 mg/kg zymosan and then irradiated with 7 Gy X-rays. The survival rate, spleen index and thymus index were evaluated. The protective effect of zymosan against radiation in vivo was compared to that of 10 mg/kg LPS a positive control. Results: The viability and apoptosis of cells treated with different doses of zymosan for different treatment times were not different from those of control cells (p<0.05). Furthermore, cell viability and apoptosis were clearly improved after zymosan preadministration (p<0.05). The radioprotective effect of zymosan was dose-dependent. In addition, the viability of cells pretreated with zymosan was higher than that of cells pretreated with LPS, and the apoptosis rate of zymosan-treated cells was lower than that of cells pretreated with LPS (p<0.05). In vivo, weight, the spleen index and the thymus index were significantly decreased by zymosan at a concentration of 20 mg/kg (p<0.05). Further experiments showed that the concentration at which zymosan exerted radioprotective effects was 10 mg/kg. The radioprotective effect of zymosan was better than that of LPS pretreatment (p<0.05). Conclusion: Zymosan is nontoxic to cells and exerts a better radioprotective effect than LPS.


2021 ◽  
Vol 15 (Supplement_1) ◽  
pp. S141-S141
Author(s):  
B Liu ◽  
M Spalinger ◽  
L G Perez ◽  
A Machicote ◽  
N Gagliani ◽  
...  

Abstract Background Inflammatory Bowel Disease (IBD) is characterized by an overwhelming gut inflammation, where CD4+ effector T cells are main mediators of the inflammatory response. Tofacitinib, a small molecular drug recently used in IBD patients, blocks the JAK/STAT signaling pathway necessary for CD4+ effector T-cell activation. However, clinical data show that a percentage of patients do not respond to the treatment. Our main goal is to identify biomarkers predicting the response of patients to tofacitinib. Methods Tofacitinib efficacy was studied in vivo in wild type (WT) and T-cell-specific PTPN2 deficient mice (CD4-Cre;Ptpn2 floxed) in which the JAK/STAT signaling pathway is over activated. WT and PTPN2 deficient mice were gavaged with tofacitinib (50mg/kg, twice daily) or vehicle. Acute DSS-colitis was induced. Colitis development was evaluated by weight loss, colonoscopy and histology. CD4+ T cells were isolated from the colon and analyzed by flow cytometry. To study the effect of tofacitinib on T-cell differentiation, we isolated naïve T cells from mouse spleen and polarized them in vitro to different T-cell subsets with or without tofacitinib. CD4+ T cells differentiation and cytokine production were analyzed by flow cytometry. To evaluate the influence of tofacitinib on human CD4+ T cells, human peripheral blood mononuclear cells (PBMCs) from healthy donors and IBD patients were stimulated in presence of tofacitinib, and analyzed by flow cytometry. Results While no protective effect was found after tofacitinib treatment in WT mice, PTPN2 deficient mice were protected from colitis based on less weight loss, lower endoscopic and histological scores. The expression of pro-inflammatory cytokines such as IL-17 and IFN-γ by colonic CD4+ T cells was also decreased by tofacitinib. Consistent with the in vivo observations, in vitro experiments revealed a strong impact of tofacitinib on CD4+ T-cells cytokine production. In PBMCs from IBD patients, IFN-γ and TNF-α expression was strongly impacted. In contrast, in healthy donors, IL-10 was the most impacted cytokine. Finally, tofacitinib decreased the in vitro differentiation of Th1, Th2, Th17, Th22, Treg and Tr1. Conclusion In the T-cell-specific PTPN2 deficient mice, tofacitinib exerts a protective effect after DSS-induced colitis. In line with the in vivo findings, in vitro experiments show that tofacitinib has a strong impact on pro-inflammatory cytokine production, especially in the IBD patients. Taken together, these data suggest that tofacitinib might be suitable primarily for IBD patients where the JAK/STAT signaling pathway is over activated.


Author(s):  
Ching-Wen Huang ◽  
Yen-Cheng Chen ◽  
Tzu-Chieh Yin ◽  
Po-Jung Chen ◽  
Tsung-Kun Chang ◽  
...  

This study investigated the roles of low-molecular-weight fucoidan (LMWF) in enhancing the anti-cancer effects of fluoropyrimidine-based chemotherapy. HCT116 and Caco-2 cells were treated with LMWF and 5-FU. Cell viability, cell cycle, apoptosis, and migration were analyzed in both cell types. Potential mechanisms underlying how LMWF enhances the anti-cancer effects of fluoropyrimidine-based chemotherapy were also explored. The cell viability of HCT116 and Caco-2 cells was significantly reduced after treatment with a LMWF-5-FU combination. In HCT116 cells, LMWF enhanced the suppressive effects of 5-FU on cell viability through the 1) induction of cell cycle arrest in the S phase and 2) late apoptosis mediated by the Jun-N-terminal kinase (JNK) signaling pathway. In Caco-2 cells, LMWF enhanced the suppressive effects of 5-FU on cell viability through both c-mesenchymal&ndash;epithelial transition (MET)/ Kirsten Rat Sarcoma virus (KRAS)/ extracellular signal-regulated kinase (ERK) and c-MET/ phosphatidyl-inositol 3-kinases (PI3K)/ protein kinase B (AKT) signaling pathways. Moreover, LMWF enhanced the suppressive effects of 5-FU on tumor cell migration through the c-MET/ matrix metalloproteinase (MMP)-2 signaling pathway in both HCT116 and Caco-2 cells. Our results demonstrated that LMWF is a potential complementary therapy for enhancing the efficacies of fluoropyrimidine-based chemotherapy in colorectal cancers (CRCs) with the wild-type or mutated KRAS gene through different mechanisms. However, in vivo studies and in clinical trials are required to validate the results of the present study.


2018 ◽  
Vol 47 (2) ◽  
pp. 842-850 ◽  
Author(s):  
Bo Hu ◽  
Guangtao Xu ◽  
Xiaomin Zhang ◽  
Long Xu ◽  
Hong Zhou ◽  
...  

Background/Aims: Paeoniflorin (PF) is known to have anti-inflammatory and paregoric effects, but the mechanism underlying its analgesic effect remains unclear. The aim of this study was to clarify the effect of PF on Freund’s complete adjuvant (CFA)-induced inflammatory pain and explore the underlying molecular mechanism. Methods: An inflammatory pain model was established by intraplantar injection of CFA in C57BL/6J mice. After intrathecal injection of PF daily for 8 consecutive days, thermal and mechanical withdrawal thresholds, the levels of inflammatory factors TNF-α, IL-1β and IL-6, microglial activity, and the expression of Akt-NF-κB signaling pathway in the spinal cord tissue were detected by animal ethological test, cell culture, enzyme-linked immunosorbent assay, immunofluorescence histochemistry, and western blot. Results: PF inhibited the spinal microglial activation in the CFA-induced pain model. The production of proinflammatory cytokines was decreased in the central nervous system after PF treatment both in vivo and in vitro. PF further displayed a remarkable effect on inhibiting the activation of Akt-NF-κB signaling pathway in vivo and in vitro. Conclusion: These results suggest that PF is a potential therapeutic agent for inflammatory pain and merits further investigation.


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