scholarly journals Resolution of Sterile Inflammation: Role for Vitamin C

2014 ◽  
Vol 2014 ◽  
pp. 1-15 ◽  
Author(s):  
Bassem M. Mohammed ◽  
Bernard J. Fisher ◽  
Quoc K. Huynh ◽  
Dayanjan S. Wijesinghe ◽  
Charles E. Chalfant ◽  
...  

Introduction. Macrophage reprogramming is vital for resolution of acute inflammation. Parenteral vitamin C (VitC) attenuates proinflammatory states in murine and human sepsis. However information about the mechanism by which VitC regulates resolution of inflammation is limited.Methods. To examine whether physiological levels of VitC modulate resolution of inflammation, we used transgenic mice lacking L-gulono-γ-lactone oxidase. VitC sufficient/deficient mice were subjected to a thioglycollate-elicited peritonitis model of sterile inflammation. Some VitC deficient mice received daily parenteral VitC (200 mg/kg) for 3 or 5 days following thioglycollate infusion. Peritoneal macrophages harvested on day 3 or day 5 were examined for intracellular VitC levels, pro- and anti-inflammatory protein and lipid mediators, mitochondrial function, and response to lipopolysaccharide (LPS). The THP-1 cell line was used to determine the modulatory activities of VitC in activated human macrophages.Results. VitC deficiency significantly delayed resolution of inflammation and generated an exaggerated proinflammatory response toin vitroLPS stimulation. VitC sufficiency andin vivoVitC supplementation restored macrophage phenotype and function in VitC deficient mice. VitC loading of THP-1 macrophages attenuated LPS-induced proinflammatory responses.Conclusion. VitC sufficiency favorably modulates macrophage function.In vivoorin vitroVitC supplementation restores macrophage phenotype and function leading to timely resolution of inflammation.

2021 ◽  
Vol 12 ◽  
Author(s):  
Ann-Kathrin Gaiser ◽  
Shanna Bauer ◽  
Stephanie Ruez ◽  
Karlheinz Holzmann ◽  
Marcus Fändrich ◽  
...  

AA amyloidosis belongs to the group of amyloid diseases which can follow chronic inflammatory conditions of various origin. The disease is characterized by the deposition of insoluble amyloid fibrils formed by serum amyloid A1 (SAA1) leading eventually to organ failure. Macrophages are intimately involved in the fibrillogenesis as well as in the clearance of amyloid fibrils. In vivo, macrophages may occur as classically (M1) or alternatively activated (M2) macrophages. We investigate here how SAA1 might affect the macrophage phenotype and function. Gene microarray analysis revealed upregulation of 64 M1-associated genes by SAA1. M1-like polarization was further confirmed by the expression of the M1-marker MARCO, activation of the NF-κB transcription factor, and secretion of the M1-cytokines TNF-α, IL-6, and MCP-1. Additionally, we demonstrate here that M1-polarized macrophages exhibit enhanced fibrillogenic activity towards SAA1. Based on our data, we propose reconsideration of the currently used cellular amyloidosis models towards an in vitro model employing M1-polarized macrophages. Furthermore, the data suggest macrophage repolarization as potential intervention strategy in AA amyloidosis.


2021 ◽  
Vol 8 ◽  
Author(s):  
Jamal Hussen

The dromedary camel (Camelus dromedarius) is well-adapted to the desert environment with the ability to tolerate increased internal body temperatures rising daily to 41–42°C during extreme hot. This study was undertaken to assess whether in vitro incubation of camel blood at 41°C, simulating conditions of heat stress, differently alters cell vitality, phenotype, and function of leukocytes, compared to incubation at 37°C (normothermia). Using flow cytometry, the cell vitality (necrosis and apoptosis), the expression of several cell markers and adhesion molecules, and the antimicrobial functions of camel leukocytes were analyzed in vitro. The fraction of apoptotic cells within the granulocytes, lymphocytes, and monocytes increased significantly after incubation of camel whole blood at 41°C for 4 h. The higher increase in apoptotic granulocytes and monocytes compared to lymphocytes suggests higher resistance of camel lymphocytes to heat stress. Functionally, incubation of camel blood at 41°C for 4 h enhanced the phagocytosis and ROS production activities of camel neutrophils and monocytes toward S. aureus. Monocytes from camel blood incubated at 41°C for 4 h significantly decreased their expression level of MHC class II molecules with no change in the abundance of CD163, resulting in a CD163high MHC-IIlow M2-like macrophage phenotype. In addition, heat stress treatment showed an inhibitory effect on the LPS-induced changes in camel monocytes phenotype. Furthermore, in vitro incubation of camel blood at 41°C reduced the expression of the cell adhesion molecules CD18 and CD11a on neutrophils and monocytes. Collectively, the present study identified some heat-stress-induced phenotypic and functional alterations in camel blood leukocytes, providing a paradigm for comparative immunology in the large animals. The clinical relevance of the observed changes in camel leukocytes for the adaptation of the camel immune response to heat stress conditions needs further in vitro and in vivo studies.


Cancers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2868
Author(s):  
Ioannis Karagiannidis ◽  
Eliane de Santana Van Vilet ◽  
Erika Said Abu Egal ◽  
Brandon Phinney ◽  
Damian Jacenik ◽  
...  

Tumor-associated macrophages (TAMs) in the gastrointestinal tumor microenvironment (TME) are known to polarize into populations exhibiting pro- or anti-tumoral activity in response to stimuli such as growth factors and cytokines. Our previous work has recognized granulocyte colony-stimulating factor (G-CSF) as a cytokine capable of influencing immune cells of the TME exhibiting pro-tumoral activity. Here, we aimed to focus on how G-CSF regulates TAM phenotype and function and the effects on gastrointestinal (GI) tumor progression. Thus, wildtype (WT) and G-CSFR−/− macrophages were examined for cytokine production, gene expression, and transcription factor activity. Adoptive transfer of WT or G-CSFR−/− macrophages into tumor-bearing mice was performed to study their influence in the progression of colon (MC38) and pancreatic (PK5L1940) tumor mouse models. Finally, the difference in cytotoxic potential between WT and G-CSFR−/− macrophages was examined both in vitro and in vivo. Our results indicate that G-CSF promotes increased IL-10 production and decreased IL-12 production, which was reversed in G-CSFR−/− macrophages for a pro-inflammatory phenotype. Furthermore, G-CSFR−/− macrophages were characterized by higher levels of NOS2 expression and NO production, which led to greater tumor related cytotoxicity both in vitro and in vivo. Our results suggest that in the absence of G-CSFR, macrophage-related tumor cytotoxicity was amplified. These findings, along with our previous reports, pinpoint G-CSF /G-CSFR as a prominent target for possible clinical applications that aim to control the TME and the GI tumor progression.


2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Veedamali S. Subramanian ◽  
Trevor Teafatiller ◽  
Anshu Agrawal ◽  
Masashi Kitazawa ◽  
Jonathan S. Marchant

Vitamin C (ascorbic acid: AA) uptake in neurons occurs via the sodium-dependent vitamin C transporter-2 (SVCT2), which is highly expressed in the central nervous system (CNS). During chronic neuroinflammation or infection, CNS levels of lipopolysaccharide (LPS) and LPS-induced tumor necrosis factor-α (TNFα) are increased. Elevated levels of LPS and TNFα have been associated with neurodegenerative diseases together with reduced levels of AA. However, little is known about the impacts of LPS and TNFα on neuronal AA uptake. The objective of this study was to examine the effect of LPS and TNFα on SVCT2 expression and function using in vitro and in vivo approaches. Treatment of SH-SY5Y cells with either LPS or TNFα inhibited AA uptake. This reduced uptake was associated with a significant decrease in SVCT2 protein and mRNA levels. In vivo exposure to LPS or TNFα also decreased SVCT2 protein and mRNA levels in mouse brains. Both LPS and TNFα decreased SLC23A2 promoter activity. Further, the inhibitory effect of LPS on a minimal SLC23A2 promoter was attenuated when either the binding site for the transcription factor Sp1 was mutated or cells were treated with the NF-κB inhibitor, celastrol. We conclude that inflammatory signals suppress AA uptake by impairing SLC23A2 transcription through opposing regulation of Sp1 and NF-κB factors.


Blood ◽  
2000 ◽  
Vol 96 (6) ◽  
pp. 2277-2283 ◽  
Author(s):  
Veronika Sexl ◽  
Roland Piekorz ◽  
Richard Moriggl ◽  
Juerg Rohrer ◽  
Michael P. Brown ◽  
...  

Abstract The cytokines interleukin 7 (IL-7) and interleukin 4 (IL-4) regulate lymphoid differentiation and function and activate the transcription factor Stat5. Using mice deficient for the 2 highly related transcription factors, Stat5a and Stat5b (Stat5a/b−/−), we investigated the role of Stat5 for B-cell differentiation, expansion, and function. Peripheral blood B cells of Stat5-deficient mice are significantly reduced, but no proliferation defects in response to various mitogenic stimuli are found. Also, IgM and IgG1 antibody production and immunoglobulin class switching are not affected. Pre- and pro-B cells of Stat5-deficient animals were found to have reduced responses to IL-7. Pro- and pre-B cells are the target cells of the abloncogene and numerous studies have suggested that Stat5a/b is essential for transformation by derivatives of the Abelson(abl) gene. To assess the role of Stat5a/b in transformation, we have evaluated the ability of variousabl derivatives to transform cells from Stat5a/b-deficient mice in vitro or in vivo. We demonstrate that the absence of Stat5a/b is not essential for the induction of lymphoid or myeloid tumors in vivo or on the ability to transform bone marrow cells in vitro.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 2128-2128 ◽  
Author(s):  
Qiaozhi Wei ◽  
Paul S. Frenette

Abstract Definitive mammalian erythropoiesis occurs in a specialized niche called erythroblastic island (EI), which is composed of a central macrophage surrounded by maturing erythroblasts. The attachment of the developing erythroblasts to the central macrophages within the islands has been suggested to be critical for the survival, proliferation and regulated differentiation of the developing erythrocytes both in vitro and in vivo. Several adhesion molecules have been suggested to mediate the interaction between the macrophage and erythroblasts in the EI niche. However, cell type-specific requirement of these molecules for EI formation and function in vivo hasn't been examined. We sought to identify the crucial adhesion molecule(s) responsible for the in vivo EI function using macrophage-specific conditional deletion mouse models. As Vascular Cell Adhesion Molecule-1 (VCAM1) has been suggested to play a key role in erythropoiesis, we deleted the gene selectively in macrophage by crossing Vcam1fl/fl mice with Csf1r-Cre transgenic mice. Our results revealed that macrophage VCAM1 was not required for steady-state erythropoiesis in vivo since bone marrow and spleen erythroblasts and hematocrit levels were not altered. Stress erythropoiesis induced by phenylhydrazine (PHZ) led to mild deficit in hematocrit recovery but no significant anemia, suggesting the contribution of other adhesion receptors. We next generated a conditional floxed allele of the Macrophage Erythroblast Attacher (Maea), which has also been suggested to be an important component of the erythroblastic niche (Soni et al. J. Biol. Chem, 2006). Efficient ablation ofMAEA (~2-fold protein level reduction on macrophages) using Csf1r-Cre resulted in a more than 3-fold reduction of leukocyte counts (p=0.003), but no significant anemia in peripheral blood. However, the cellularity in the bone marrow was significantly reduced in Maea -deficient mice, owing largely to > 2-fold reduction of erythroblasts (p=0.01). Analyses of erythroblast maturation by FACS revealed a significant increase in the proportion of the less mature erythroblasts at the expenses of terminal differentiation, indicating that MAEA regulates erythroblast maturation. Interestingly, BM macrophage numbers were also severely affected in Maea -deficient mice (~4-fold reduction, p=0.01), suggesting a role for MAEA in macrophage development. By contrast, the spleen of Maeafl/-; Csf1r-Cre mice did not exhibit any reduction in erythroblast numbers, indicating that the erythroblast-macrophage interaction may be differentially regulated in BM and spleen. Unexpectedly, Maea ablation impaired the engraftment ability of BM hematopoietic stem and progenitors (HSPCs) after transplantation, suggesting broader functions for this protein in hematopoiesis. These studies identify MAEA as a critical adhesion mediator between the erythroblasts and central macrophages in adult murine bone marrow. Ongoing studies will shed light on its involvement in stress and pathological erythropoiesis and HSPC regulation. Disclosures No relevant conflicts of interest to declare.


Blood ◽  
2000 ◽  
Vol 96 (6) ◽  
pp. 2277-2283 ◽  
Author(s):  
Veronika Sexl ◽  
Roland Piekorz ◽  
Richard Moriggl ◽  
Juerg Rohrer ◽  
Michael P. Brown ◽  
...  

The cytokines interleukin 7 (IL-7) and interleukin 4 (IL-4) regulate lymphoid differentiation and function and activate the transcription factor Stat5. Using mice deficient for the 2 highly related transcription factors, Stat5a and Stat5b (Stat5a/b−/−), we investigated the role of Stat5 for B-cell differentiation, expansion, and function. Peripheral blood B cells of Stat5-deficient mice are significantly reduced, but no proliferation defects in response to various mitogenic stimuli are found. Also, IgM and IgG1 antibody production and immunoglobulin class switching are not affected. Pre- and pro-B cells of Stat5-deficient animals were found to have reduced responses to IL-7. Pro- and pre-B cells are the target cells of the abloncogene and numerous studies have suggested that Stat5a/b is essential for transformation by derivatives of the Abelson(abl) gene. To assess the role of Stat5a/b in transformation, we have evaluated the ability of variousabl derivatives to transform cells from Stat5a/b-deficient mice in vitro or in vivo. We demonstrate that the absence of Stat5a/b is not essential for the induction of lymphoid or myeloid tumors in vivo or on the ability to transform bone marrow cells in vitro.


Author(s):  
Alison Gartland ◽  
Katherine A. Buckley ◽  
Robert A. Hipskind ◽  
M. J. Perry ◽  
J. H. Tobias ◽  
...  

Author(s):  
С.В. Калиш ◽  
С.В. Лямина ◽  
А.А. Раецкая ◽  
И.Ю. Малышев

Цель исследования. Репрограммирование М1 фенотипа макрофагов с ингибированными факторами транскрипции М2 фенотипа STAT3, STAТ6 и SMAD и оценка их влияния на развитие карциномы Эрлиха (КЭ) in vitro и in vivo. Методика. Рост опухоли иницировали in vitro путем добавления клеток КЭ в среду культивирования RPMI-1640 и in vivo путем внутрибрюшинной инъекции клеток КЭ мышам. Результаты. Установлено, что M1макрофаги и in vitro, и in vivo оказывают выраженный противоопухолевый эффект, который превосходит антиопухолевые эффекты М1, M1, M1 макрофагов и цисплатина. Заключение. М1 макрофаги с ингибированными STAT3, STAT6 и/или SMAD3 эффективно ограничивают рост опухоли. Полученные данные обосновывают разработку новой технологии противоопухолевой клеточной терапии. Objective. Reprogramming of M1 macrophage phenotype with inhibited M2 phenotype transcription factors, such as STAT3, STAT6 and SMAD and assess their impact on the development of Ehrlich carcinoma (EC) in vitro and in vivo . Methods. Tumor growth in vitro was initiated by addition of EC cells in RPMI-1640 culture medium and in vivo by intraperitoneal of EC cell injection into mice. Results. It was found that M1 macrophages have a pronounced anti-tumor effect in vitro , and in vivo , which was greater than anti-tumor effects of M1, M1, M1 macrophages and cisplatin. Conclusion. M1 macrophages with inhibited STAT3, STAT6 and/or SMAD3 effectively restrict tumor growth. The findings justify the development of new anti-tumor cell therapy technology.


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