scholarly journals N-Formyl Methionine Peptide-Mediated Neutrophil Activation in Systemic Sclerosis

2022 ◽  
Vol 12 ◽  
Author(s):  
Runa Kuley ◽  
Ryan D. Stultz ◽  
Bhargavi Duvvuri ◽  
Ting Wang ◽  
Marvin J. Fritzler ◽  
...  

Exaggerated neutrophil activation and formation of neutrophil extracellular traps (NETs) are reported in systemic sclerosis (SSc) but its involvement in SSc pathogenesis is not clear. In the present study we assessed markers of neutrophil activation and NET formation in SSc patients in relation to markers of inflammation and disease phenotype. Factors promoting neutrophil activation in SSc remain largely unknown. Among the neutrophil activating factors, mitochondrial-derived N-formyl methionine (fMet) has been reported in several autoinflammatory conditions. The aim of the current study is to assess whether SSc patients have elevated levels of fMet and the role of fMet in neutrophil-mediated inflammation on SSc pathogenesis. Markers of neutrophil activation (calprotectin, NETs) and levels of fMet were analyzed in plasma from two SSc cohorts (n=80 and n=20, respectively) using ELISA. Neutrophil activation assays were performed in presence or absence of formyl peptide receptor 1 (FPR1) inhibitor cyclosporin H. Elevated levels of calprotectin and NETs were observed in SSc patients as compared to healthy controls (p<0.0001) associating with SSc clinical disease characteristics. Further, SSc patients had elevated levels of circulating fMet as compared to healthy controls (p<0.0001). Consistent with a role for fMet-mediated neutrophil activation, fMet levels correlated with levels of calprotectin and NETs (r=0.34, p=0.002; r=0.29, p<0.01 respectively). Additionally, plasma samples from SSc patients with high levels of fMet induced de novo neutrophil activation through FPR1-dependent mechanisms. Our data for the first time implicates an important role for the mitochondrial component fMet in promoting neutrophil-mediated inflammation in SSc.

2009 ◽  
Vol 36 (6) ◽  
pp. 1230-1234 ◽  
Author(s):  
ISABELA J. WASTOWSKI ◽  
PERCIVAL D. SAMPAIO-BARROS ◽  
ELIANE M.I. AMSTALDEN ◽  
GUSTAVO MARTELLI PALOMINO ◽  
JOÃO FRANCISCO MARQUES-NETO ◽  
...  

Objective.To determine HLA-G expression in skin biopsies from patients with systemic sclerosis (SSc), and its association with epidemiological, clinical, and laboratory variables and survival.Methods.Paraffin-embedded skin biopsies obtained from 21 SSc patients (14 limited SSc, 7 diffuse SSc) and from 28 healthy controls were studied. HLA-G expression was evaluated by immunohistochemistry.Results.HLA-G molecules were detected in 57% of skin biopsies from patients with SSc (9 from limited SSc, 3 from diffuse SSc), whereas no control sample expressed HLA-G (p = 0.000004). In patients, HLA-G molecules were consistently observed within epidermal and some dermal cells. HLA-G expression was associated with a lower frequency of vascular cutaneous ulcers (p = 0.0004), telangiectasias (p = 0.008), and inflammatory polyarthralgia (p = 0.02). After a 15-year followup, SSc patients who exhibited HLA-G survived longer than patients who did not.Conclusion.HLA-G is expressed in skin biopsies from patients with SSc, and this is associated with a better disease prognosis. This suggests a modulatory role of HLA-G in SSc, as observed in other skin disorders.


Diagnostics ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2116
Author(s):  
Marija Geroldinger-Simić ◽  
Thomas Bögl ◽  
Markus Himmelsbach ◽  
Norbert Sepp ◽  
Wolfgang Buchberger

Systemic sclerosis (SSc) is an autoimmune disease with fibrosis of the skin and/or internal organs, causing a decrease in quality of life and survival. There is no causative therapy, and the pathophysiology of the SSc remains unclear. Studies showed that lipid metabolism was relevant for autoimmune diseases, but little is known about the role of lipids in SSc. In the present study, we sought to explore the phospholipid profile of SSc by using the lipidomics approach. We also aimed to analyze lipidomics results for different clinical manifestations of SSc. Experiments were performed using high-performance liquid chromatography coupled to mass spectrometry for the lipidomic profiling of plasma samples from patients with SSc. Our study showed, for the first time, significant changes in the level of phospholipids such as plasmalogens and sphingomyelins from the plasma of SSc patients as compared to controls. Phosphatidylcholine plasmalogens species and sphingomyelins were significantly increased in SSc patients as compared to controls. Our results also demonstrated a significant association of changes in the metabolism of phospholipids (phosphatidylcholine and phosphatidylethanolamine plasmalogens species and sphingomyelins) with different clinical manifestations of SSc. Further lipidomic studies might lead to the detection of lipids as new biomarkers or therapeutic targets of SSc.


Author(s):  
Igor Snapkov ◽  
Carl Otto Öqvist ◽  
Yngve Anton Figenschau ◽  
Per Kogner ◽  
John Inge Johnsen ◽  
...  

Author(s):  
Elisabeth Weiß ◽  
Katja Schlatterer ◽  
Christian Beck ◽  
Andreas Peschel ◽  
Dorothee Kretschmer

Abstract Background Formyl-peptide receptors (FPRs) are important pattern recognition receptors that sense specific bacterial peptides. Formyl-peptide receptors are highly expressed on neutrophils and monocytes, and their activation promotes the migration of phagocytes to sites of infection. It is currently unknown whether FPRs may also influence subsequent processes such as bacterial phagocytosis and killing. Staphylococcus aureus, especially highly pathogenic community-acquired methicillin-resistant S aureus strains, release high amounts of FPR2 ligands, the phenol-soluble modulins. Methods We demonstrate that FPR activation leads to upregulation of complement receptors 1 and 3 as well as FCγ receptor I on neutrophils and, consequently, increased opsonic phagocytosis of S aureus and other pathogens. Results Increased phagocytosis promotes killing of S aureus and interleukin-8 release by neutrophils. Conclusions We show here for the first time that FPRs govern opsonic phagocytosis. Manipulation of FPR2 activation could open new therapeutic opportunities against bacterial pathogens.


2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Peng Huang ◽  
Yuxiang Zhou ◽  
Zan Liu ◽  
Pihong Zhang

Decreased Th1/Th2 ratio is one of the major characteristics of immunosuppression in sepsis. Both membrane adhesive protein Annexin-A1 (ANXA1) and transcription factor GATA-3 have been reported to play important roles in T cell differentiation. However, the relationship between ANXA1 and GATA-3 in Th1/Th2 shift is unknown. Our study investigated the interaction effects of ANXA1 and GATA-3 to influence T cell differentiation in CD4+ T cells. We found that GATA-3 and ANXA1 were coexpressed on Th0/Th1/Th2 cytoplasm and nuclear. Overexpressed ANXA1 significantly increased the expression of IFNγ and reduced IL-4 expression in T cells, while ANXA1-silenced T cells exhibited decreased production of IFNγ and increased production of IL-4. Knockdown of ANXA1 promoted higher expression level of GATA-3 and low level of T-box transcription factor (T-bet/Tbx21). Further study demonstrated that ANXA1 regulated GATA-3 expression through the formyl peptide receptor like-1 (FPRL-1) downstream signaling pathways ERK and PKB/Akt. These results suggested that ANXA1 modulates GATA-3/T-bet expression induced Th0/Th1 differentiation. Moreover, we found that GATA-3 inhibited ANXA1 expression by binding to its promoter for the first time. It is proposed that the interactions between ANXA1 and GATA-3 may provide clues to understand the immunosuppression and have potential as new therapeutic targets in immunotherapy after sepsis.


2012 ◽  
Vol 39 (6) ◽  
pp. 1275-1279 ◽  
Author(s):  
F. DAVID CARMONA ◽  
AURORA SERRANO ◽  
LUIS RODRÍGUEZ-RODRÍGUEZ ◽  
JOSÉ LUIS CALLEJAS ◽  
CARMEN P. SIMEÓN ◽  
...  

Objective.We evaluated whether a single-nucleotide polymorphism (SNP) of theTRAF6gene previously associated with systemic lupus erythematosus and rheumatoid arthritis may be a common risk factor for systemic sclerosis (SSc) and giant cell arteritis (GCA).Methods.A total of 1185 patients with SSc, 479 patients with biopsy-proven GCA, and 1442 unrelated healthy controls of white Spanish origin were genotyped for the rs540386 variant using a specifically designed TaqMan©allele discrimination assay.Results.No significant associations of this SNP with global SSc or GCA were found. This was also the case when the potential associations of theTRAF6polymorphism with the main clinical phenotypes of the 2 diseases (e.g., limited cutaneous and diffuse cutaneous SSc, or presence of polymyalgia rheumatica and visual ischemic manifestations in GCA) were assessed.Conclusion.Our data do not support a role of the rs540386TRAF6variant as a key component of the genetic network underlying SSc and GCA.


2020 ◽  
Vol 18 (3) ◽  
pp. 229-249 ◽  
Author(s):  
Ewa Trojan ◽  
Natalia Bryniarska ◽  
Monika Leśkiewicz ◽  
Magdalena Regulska ◽  
Katarzyna Chamera ◽  
...  

: Chronic inflammatory processes within the central nervous system (CNS) are in part responsible for the development of neurodegenerative and psychiatric diseases. These processes are associated with, among other things, the increased and disturbed activation of microglia and the elevated production of proinflammatory factors. Recent studies indicated that the disruption of the process of resolution of inflammation (RoI) may be the cause of CNS disorders. It is shown that the RoI is regulated by endogenous molecules called specialized pro-resolving mediators (SPMs), which interact with specific membrane receptors. Some SPMs activate formyl peptide receptors (FPRs), which belong to the family of seven-transmembrane G protein-coupled receptors. These receptors take part not only in the proinflammatory response but also in the resolution of the inflammation process. Therefore, the activation of FPRs might have complex consequences. : This review discusses the potential role of FPRs, and in particular the role of FPR2 subtype, in the brain under physiological and pathological conditions and their involvement in processes underlying neurodegenerative and psychiatric disorders as well as ischemia, the pathogenesis of which involves the dysfunction of inflammatory processes.


2019 ◽  
Author(s):  
M Nati ◽  
A Chatzigeorgiou ◽  
LS Chen ◽  
A Neuwirth ◽  
P Subramanian ◽  
...  

2002 ◽  
Vol 282 (2) ◽  
pp. F316-F323 ◽  
Author(s):  
Marcella M. Hallemeesch ◽  
Peter B. Soeters ◽  
Nicolaas E. P. Deutz

The kidney has an important function in arginine metabolism, because the kidney is the main endogenous source for de novo arginine production from circulating citrulline. In conditions such as sepsis, nitric oxide (NO) production is increased and is dependent on extracellular arginine availability. To elucidate the adaptive role of renal de novo arginine synthesis in a condition of increased NO production, we studied renal arginine metabolism in a mouse model of endotoxemia. Because arginine flux is largely dependent on protein flux, we also measured protein metabolism in mice. Female mice were injected intraperitoneally with lipopolysaccharide; control mice received 0.9% NaCl. Six hours later, renal blood flow was measured with the use of para-aminohippuric acid. Arginine and protein metabolism were studied using organ-balance, stable-isotope techniques. Systemic NO production was increased in the endotoxin-treated mice. In addition, renal protein synthesis and de novo arginine production from citrulline were increased. However, no effect on renal NO production was observed. In conclusion, increased renal de novo arginine production may serve to sustain systemic NO production. To our knowledge, it was shown for the first time that renal protein synthesis is enhanced in the early response to endotoxemia.


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