Local production of TGF β1 inhibits cerebral edema, enhances TNF-α induced apoptosis and improves survival in a murine glioma model

Abstract Background Chronic inflammation with sustained unregulated immune stimulation in autoimmune rheumatic diseases (ARD) may be a risk factor for developing lymphoproliferative disorders (LPD). Markers of ARD activity as high erythrocyte sedimentation rate or erosive joint diseases and the development of B-symptoms were accounted as risk factors for LPD development. We investigated the association of five inflammatory cytokine genes single nucleotide polymorphisms (SNPs): TNF-α -308G>A; TGF-β1 gene codon 10 T>C and 25 G>C; IL-10 promoter SNPs -1082 A>G, -819T>C, and -592A>C; IL-6 -174G>C; and IFN-γ 874 T>A with the risk of LPD development in ARD patients. The study was conducted on 70 patients divided into group I, 25 ARD patients diagnosed as RA (n = 15) and SLE (n = 10) and with no history of malignancy; group II, 25 patients diagnosed with LPD and had no ARD; and group III, 20 patients diagnosed with both diseases: ARD and LPD. Cytokine genotyping was analyzed by PCR-sequence-specific primer (PCR-SSP). Results ARD+LPD patients had significantly higher frequency of TNF-α -308A allele and AA+AG genotype (high TNF-α producers) and IL-10 -1082A allele and AA genotype (low IL-10 producers) than ARD patients (p = 0.003, p = 0.024, p = 0.003, p = 0.03, respectively) with a significantly increased risk of LPD development in ARD patients expressing the corresponding alleles and genotypes. No significant differences were detected in the distribution frequency of either TGF-β1, IL-6, or IFN-γ SNPs between groups I and III or any of the studied SNPs between groups II and III. The distribution frequency of IL-10 ATA haplotype was significantly increased in group III as compared to group I (p = 0.037). Conclusion The significantly increased frequency of the high-TNF-α- and low-IL-10-producing alleles and genotypes in ARD patients may participate in the provision of a proinflammatory milieu that eventually increases the risk of LPD development.

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Pirfenidone attenuates synovial fibrosis and postpones the progression of osteoarthritis by anti-fibrotic and anti-inflammatory properties in vivo and in vitro

Journal of Translational Medicine ◽

10.1186/s12967-021-02823-4 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Qilu Wei ◽

Ning Kong ◽

Xiaohui Liu ◽

Run Tian ◽

Ming Jiao ◽

...

Keyword(s):

Protein Expression ◽

Cell Counting ◽

Enzyme Linked Immunosorbent Assay ◽

Fast Green ◽

Expression Levels ◽

Tnf Α ◽

Anti Inflammatory ◽

Safranin O ◽

Tgf Β1

Abstract Background Osteoarthritis (OA) is a disease of the entire joint involving synovial fibrosis and inflammation. Pathological changes to the synovium can accelerate the progression of OA. Pirfenidone (PFD) is a potent anti-fibrotic drug with additional anti-inflammatory properties. However, the influence of PFD on OA is unknown. Methods Proliferation of human fibroblast-like synoviocytes (FLSs) after treatment with TGF-β1 or PFD was evaluated using a Cell Counting Kit-8 assay and their migration using a Transwell assay. The expression of fibrosis-related genes (COL1A1, TIMP-1, and ACTA-2) and those related to inflammation (IL-6 and TNF-α) was quantified by real-time quantitative PCR. The protein expression levels of COL1A1, α-SMA (coded by ACTA-2), IL-6 and TNF-α were measured by enzyme-linked immunosorbent assay. A rabbit model of OA was established and then PFD was administered by gavage. The expression of genes related to fibrosis (COL1A1, TIMP-1, and ADAM-12) and inflammation (IL-6 and TNF-α) was measured using RNA extracted from the synovium. Synovial tissue was examined histologically after staining with H&E, Masson’s trichrome, and immunofluorescence. Synovitis scores, the volume fraction of collagen, and mean fluorescence intensity were calculated. Degeneration of articular cartilage was analyzed using a Safranin O-fast green stain and OARSI grading. Results The proliferation of FLSs was greatest when induced with 2.5 ng/ml TGF-β1 although it did not promote their migration. Therefore, 2.5 ng/ml TGF-β1 was used to stimulate the FLSs and evaluate the effects of PFD, which inhibited the migration of FLSs at concentrations as low as 1.0 mg/ml. PFD decreased the expression of COL1A1 while TGF-β1 increased both mRNA and protein expression levels of IL-6 but had no effect on α-SMA or TNF-α expression. PFD decreased mRNA expression levels of COL1A1, IL-6, and TNF-α in vivo. H&E staining and synovitis scores indicated that PFD reduced synovial inflammation, while Masson’s trichrome and immunofluorescence staining suggested that PFD decreased synovial fibrosis. Safranin O-Fast Green staining and the OARSI scores demonstrated that PFD delayed the progression of OA. Conclusions PFD attenuated synovial fibrosis and inflammation, and postponed the progression of osteoarthritis in a modified Hulth model of OA in rabbits, which was related to its anti-fibrotic and anti-inflammatory properties.

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From Inflammation to the Onset of Fibrosis through A2A Receptors in Kidneys from Deceased Donors

International Journal of Molecular Sciences ◽

10.3390/ijms21228826 ◽

2020 ◽

Vol 21 (22) ◽

pp. 8826

Author(s):

Elena Guillén-Gómez ◽

Irene Silva ◽

Núria Serra ◽

Francisco Caballero ◽

Jesús Leal ◽

...

Keyword(s):

Deceased Donor ◽

Inflammatory Factors ◽

Mrna Levels ◽

A2a Adenosine Receptor ◽

A2a Receptors ◽

Tnf Α ◽

Anti Inflammatory ◽

Pka Pathway ◽

Tgf Β1 ◽

M2 Phenotype

Pretransplant graft inflammation could be involved in the worse prognosis of deceased donor (DD) kidney transplants. A2A adenosine receptor (A2AR) can stimulate anti-inflammatory M2 macrophages, leading to fibrosis if injury and inflammation persist. Pre-implantation biopsies of kidney donors (47 DD and 21 living donors (LD)) were used to analyze expression levels and activated intracellular pathways related to inflammatory and pro-fibrotic processes. A2AR expression and PKA pathway were enhanced in DD kidneys. A2AR gene expression correlated with TGF-β1 and other profibrotic markers, as well as CD163, C/EBPβ, and Col1A1, which are highly expressed in DD kidneys. TNF-α mRNA levels correlated with profibrotic and anti-inflammatory factors such as TGF-β1 and A2AR. Experiments with THP-1 cells point to the involvement of the TNF-α/NF-κB pathway in the up-regulation of A2AR, which induces the M2 phenotype increasing CD163 and TGF-β1 expression. In DD kidneys, the TNF-α/NF-κB pathway could be involved in the increase of A2AR expression, which would activate the PKA–CREB axis, inducing the macrophage M2 phenotype, TGF-β1 production, and ultimately, fibrosis. Thus, in inflamed DD kidneys, an increase in A2AR expression is associated with the onset of fibrosis, which may contribute to graft dysfunction and prognostic differences between DD and LD transplants.

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Cell Death Signaling Pathway Induced by Cholix Toxin, a Cytotoxin and eEF2 ADP-Ribosyltransferase Produced by Vibrio cholerae

Toxins ◽

10.3390/toxins13010012 ◽

2020 ◽

Vol 13 (1) ◽

pp. 12

Author(s):

Kohei Ogura ◽

Kinnosuke Yahiro ◽

Joel Moss

Keyword(s):

Cell Death ◽

Protein Kinase ◽

Vibrio Cholerae ◽

Elongation Factor ◽

Host Cells ◽

Mitogen Activated Protein Kinase ◽

Pseudomonas Exotoxin A ◽

Tnf Α ◽

Induced Apoptosis ◽

Adp Ribosyltransferase

Pathogenic microorganisms produce various virulence factors, e.g., enzymes, cytotoxins, effectors, which trigger development of pathologies in infectious diseases. Cholera toxin (CT) produced by O1 and O139 serotypes of Vibrio cholerae (V. cholerae) is a major cytotoxin causing severe diarrhea. Cholix cytotoxin (Cholix) was identified as a novel eukaryotic elongation factor 2 (eEF2) adenosine-diphosphate (ADP)-ribosyltransferase produced mainly in non-O1/non-O139 V. cholerae. The function and role of Cholix in infectious disease caused by V. cholerae remain unknown. The crystal structure of Cholix is similar to Pseudomonas exotoxin A (PEA) which is composed of an N-terminal receptor-recognition domain and a C-terminal ADP-ribosyltransferase domain. The endocytosed Cholix catalyzes ADP-ribosylation of eEF2 in host cells and inhibits protein synthesis, resulting in cell death. In a mouse model, Cholix caused lethality with severe liver damage. In this review, we describe the mechanism underlying Cholix-induced cytotoxicity. Cholix-induced apoptosis was regulated by mitogen-activated protein kinase (MAPK) and protein kinase C (PKC) signaling pathways, which dramatically enhanced tumor necrosis factor-α (TNF-α) production in human liver, as well as the amount of epithelial-like HepG2 cancer cells. In contrast, Cholix induced apoptosis in hepatocytes through a mitochondrial-dependent pathway, which was not stimulated by TNF-α. These findings suggest that sensitivity to Cholix depends on the target cell. A substantial amount of information on PEA is provided in order to compare/contrast this well-characterized mono-ADP-ribosyltransferase (mART) with Cholix.

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Regulation of extracellular matrix synthesis by TNF-α and TGF-β1 in type II cells exposed to coal dust

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1998.275.4.l637 ◽

1998 ◽

Vol 275 (4) ◽

pp. L637-L644 ◽

Cited By ~ 3

Author(s):

Yu-Chen Lee ◽

D. Eugene Rannels

Keyword(s):

Extracellular Matrix ◽

Cell Cultures ◽

Transforming Growth Factor ◽

Coal Dust ◽

Transforming Growth Factor Β1 ◽

Type Ii ◽

Tnf Α ◽

Type Ii Cell ◽

Primary Type ◽

Tgf Β1

Type II pulmonary epithelial cells respond to anthracite coal dust PSOC 867 with increased synthesis of extracellular matrix (ECM) components. Alveolar macrophages modulate this response by pathways that may involve soluble mediators, including tumor necrosis factor-α (TNF-α) or transforming growth factor-β1 (TGF-β1). The effects of TNF-α (10 ng/ml) and/or TGF-β1 (2 ng/ml) were thus investigated in dust-exposed primary type II cell cultures. In control day 1 or day 3 cultures, TNF-α and/or TGF-β1 had little or no effect on the synthesis of type II cellular proteins, independent of whether the cells were exposed to dust. With PSOC 867 exposure, where ECM protein synthesis is elevated, TNF-α and TGF-β1 further increased both the absolute and relative rates of ECM synthesis on day 3 but had little effect on day 1. Each mediator increased expression of fibronectin mRNA, as well as of ECM fibronectin content, in a manner qualitatively similar to their effects on synthesis. Thus TNF-α and TGF-β1 modulate both ECM synthesis and fibronectin content in coal dust-exposed type II cell cultures.

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NF-κB Activation Is Related to the Resistance of Lung Cancer Cells to TNF-α-Induced Apoptosis

Biochemical and Biophysical Research Communications ◽

10.1006/bbrc.2000.2909 ◽

2000 ◽

Vol 273 (1) ◽

pp. 140-146 ◽

Cited By ~ 35

Author(s):

Jae-Yeol Kim ◽

Seunghee Lee ◽

Bin Hwangbo ◽

Choon-Taek Lee ◽

Young Whan Kim ◽

...

Keyword(s):

Lung Cancer ◽

Cancer Cells ◽

Lung Cancer Cells ◽

Tnf Α ◽

Induced Apoptosis

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Identification of a microRNA signature in renal fibrosis: role of miR-21

AJP Renal Physiology ◽

10.1152/ajprenal.00273.2011 ◽

2011 ◽

Vol 301 (4) ◽

pp. F793-F801 ◽

Cited By ~ 169

Author(s):

Abolfazl Zarjou ◽

Shanzhong Yang ◽

Edward Abraham ◽

Anupam Agarwal ◽

Gang Liu

Keyword(s):

Epithelial Cells ◽

Renal Fibrosis ◽

Transforming Growth Factor ◽

Response To Treatment ◽

Tubular Epithelial Cells ◽

Altered Expression ◽

Tnf Α ◽

Tgf Β1

Renal fibrosis is a final stage of many forms of kidney disease and leads to impairment of kidney function. The molecular pathogenesis of renal fibrosis is currently not well-understood. microRNAs (miRNAs) are important players in initiation and progression of many pathologic processes including diabetes, cancer, and cardiovascular disease. However, the role of miRNAs in kidney injury and repair is not well-characterized. In the present study, we found a unique miRNA signature associated with unilateral ureteral obstruction (UUO)-induced renal fibrosis. We found altered expression in UUO kidneys of miRNAs that have been shown to be responsive to stimulation by transforming growth factor (TGF)-β1 or TNF-α. Among these miRNAs, miR-21 demonstrated the greatest increase in UUO kidneys. The enhanced expression of miR-21 was located mainly in distal tubular epithelial cells. miR-21 expression was upregulated in response to treatment with TGF-β1 or TNF-α in human renal tubular epithelial cells in vitro. Furthermore, we found that blocking miR-21 in vivo attenuated UUO-induced renal fibrosis, presumably through diminishing the expression of profibrotic proteins and reducing infiltration of inflammatory macrophages in UUO kidneys. Our data suggest that targeting specific miRNAs could be a novel therapeutic approach to treat renal fibrosis.

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Transcription Factor AP-2α Is Preferentially Cleaved by Caspase 6 and Degraded by Proteasome during Tumor Necrosis Factor Alpha-Induced Apoptosis in Breast Cancer Cells

Molecular and Cellular Biology ◽

10.1128/mcb.21.15.4856-4867.2001 ◽

2001 ◽

Vol 21 (15) ◽

pp. 4856-4867 ◽

Cited By ~ 32

Author(s):

Okot Nyormoi ◽

Zhi Wang ◽

Dao Doan ◽

Maribelis Ruiz ◽

David McConkey ◽

...

Keyword(s):

Breast Cancer ◽

Breast Cancer Cells ◽

Tumor Necrosis ◽

Necrosis Factor Alpha ◽

Tnf Α ◽

Factor Alpha ◽

Caspase 6 ◽

Induced Apoptosis ◽

Necrosis Factor

ABSTRACT Several reports have linked activating protein 2α (AP-2α) to apoptosis, leading us to hypothesize that AP-2α is a substrate for caspases. We tested this hypothesis by examining the effects of tumor necrosis factor alpha (TNF-α) on the expression of AP-2 in breast cancer cells. Here, we provide evidence that TNF-α downregulates AP-2α and AP-2γ expression posttranscriptionally during TNF-α-induced apoptosis. Both a general caspase antagonist (zVADfmk) and a caspase 6-preferred antagonist (zVEIDfmk) inhibited TNF-α-induced apoptosis and AP-2α downregulation. In vivo tests showed that AP-2α was cleaved by caspases ahead of the DNA fragmentation phase of apoptosis. Recombinant caspase 6 cleaved AP-2α preferentially, although caspases 1 and 3 also cleaved it, albeit at 50-fold or higher concentrations. Activated caspase 6 was detected in TNF-α-treated cells, thus confirming its involvement in AP-2α cleavage. All three caspases cleaved AP-2α at asp19 of the sequence asp-arg-his-asp (DRHD19). Mutating D19 to A19abrogated AP-2α cleavage by all three caspases. TNF-α-induced cleavage of AP-2α in vivo led to AP-2α degradation and loss of DNA-binding activity, both of which were prevented by pretreatment with zVEIDfmk. AP-2α degradation but not cleavage was inhibited in vivo by PS-431 (a proteasome antagonist), suggesting that AP-2α is degraded subsequent to cleavage by caspase 6 or caspase 6-like enzymes. Cells transfected with green fluorescent protein-tagged mutant AP-2α are resistant to TNF-α-induced apoptosis, further demonstrating the link between caspase-mediated cleavage of AP-2α and apoptosis. This is the first report to demonstrate that degradation of AP-2α is a critical event in TNF-α-induced apoptosis. Since the DRHD sequence in vertebrate AP-2 is widely conserved, its cleavage by caspases may represent an important mechanism for regulating cell survival, proliferation, differentiation, and apoptosis.

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Prevention of TNF-α-induced apoptosis in polyamine-depleted IEC-6 cells is mediated through the activation of ERK1/2

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00342.2003 ◽

2004 ◽

Vol 286 (3) ◽

pp. G479-G490 ◽

Cited By ~ 36

Author(s):

Sujoy Bhattacharya ◽

Ramesh M. Ray ◽

Leonard R. Johnson

Keyword(s):

Epithelial Cells ◽

Cytochrome C ◽

Critical Role ◽

Dominant Negative ◽

Dominant Negative Mutant ◽

Cytochrome C Release ◽

Erk Phosphorylation ◽

Tnf Α ◽

Induced Apoptosis ◽

Jnk Activation

It has been documented that polyamines play a critical role in the regulation of apoptosis in intestinal epithelial cells. We have recently reported that protection from TNF-α/cycloheximide (CHX)-induced apoptosis in epithelial cells depleted of polyamines is mediated through the inactivation of a proapoptotic mediator, JNK. In this study, we addressed the involvement of the MAPK pathway in the regulation of apoptosis after polyamine depletion of IEC-6 cells. Polyamine depletion by α-difluromethylornithine (DFMO) resulted in the sustained activation of ERK in response to TNF-α/CHX treatment. Pretreatment of polyamine-depleted IEC-6 cells with a cell membrane-permeable MEK1/2 inhibitor, U-0126, significantly inhibited TNF-α/CHX-induced ERK phosphorylation and significantly increased DNA fragmentation, JNK activity, and caspase-3 activity in response to TNF-α/CHX. Moreover, the dose dependency of U-0126-mediated inhibition of TNF-α/ CHX-induced ERK phosphorylation correlated with the reversal of the antiapoptotic effect of DFMO. IEC-6 cells expressing constitutively active MEK1 had decreased TNF-α/CHX-induced JNK phosphorylation and were significantly protected from apoptosis. Conversely, a dominant-negative MEK1 resulted in high basal activation of JNK, cytochrome c release, and spontaneous apoptosis. Polyamine depletion of the dominant-negative MEK1 cells did not prevent JNK activation or cytochrome c release and failed to confer protection from both TNF-α/CHX and camptothecin-induced apoptosis. Finally, expression of a dominant-negative mutant of JNK significantly protected IEC-6 cells from TNF-α/CHX-induced apoptosis. These data indicate that polyamine depletion results in the activation of ERK, which inhibits JNK activation and protects cells from apoptosis.

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