METHODS OF ESTIMATION AND THE ROLE OF RESPIRATORY BURST IN THE PATHOGENESIS OF INFECTIOUS AND INFLAMMATORY DISEASES

In contrast to C5a, which represents a well-established potent activator of the respiratory burst in polymorphonuclear neutrophilic granulocytes (PMN), the functional role of C3a in the activation of PMN is, so far, poorly understood. Herein, the potential role of human C3a in the activation of the respiratory burst in human PMN was investigated. The release of reactive oxygen species (ROS) of PMN from healthy donors was measured by lucigenin-dependent chemiluminescence. C3a dose-dependently induced the production of ROS in human PMN in the range between 10 ng/mL and 1,000 ng/mL, whereas C3a-desArg was inactive. Flow cytometric measurement of H2O2 by dihydrorhodamine-123 labeling of anti-CD16-stained PMN showed that predominantly neutrophilic PMN are responsible for the C3a-induced activation of the respiratory burst. To exclude that C3a stimulation was caused by contamination with C5a, the specificity of C3a-induced activation of PMN was shown using monoclonal antibodies (MoAbs). Accordingly, the effect of C3a was completely abolished in the presence of Fab fragments of a blocking anti-C3a MoAb. In addition, blockade of the C5a receptor by the anti-C5a receptor (anti-C5aR) MoAb, S5/1, totally inhibited the C5a-induced production of ROS, whereas the C3a response in the presence of the anti-C5aR MoAb was unaffected. The specificity of the response was further confirmed by homologous desensitization after restimulation with C3a. In contrast, no cross-desensitization was observed upon stimulation with C5a. The C3a-induced ROS production by PMN was inhibited by pertussis toxin, indicating the involvement of guanine nucleotide-binding proteins (Gi proteins) in the signal transduction process initiated by C3a. In addition, stimulation of PMN by C3a resulted in a transient increase in the cytosolic free calcium concentration ([Ca2+]i) in a dose-dependent manner. In contrast to C3a- induced ROS production, C3a did not induce a chemotactic response in PMN, indicating functional qualitative differences as compared with C5a. In summary, these results show that C3a is a potent activator of the respiratory burst in human PMN. Therefore, these findings point to a novel role of C3a in the pathogenesis of inflammatory diseases associated with increased C3a levels and PMN activation.

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C3a activates the respiratory burst in human polymorphonuclear neutrophilic leukocytes via pertussis toxin-sensitive G-proteins

Blood ◽

10.1182/blood.v83.11.3324.3324 ◽

1994 ◽

Vol 83 (11) ◽

pp. 3324-3331 ◽

Cited By ~ 99

Author(s):

J Elsner ◽

M Oppermann ◽

W Czech ◽

A Kapp

Keyword(s):

Pertussis Toxin ◽

Respiratory Burst ◽

Inflammatory Diseases ◽

Free Calcium ◽

Dependent Manner ◽

Ros Production ◽

C5a Receptor ◽

Flow Cytometric Measurement ◽

Guanine Nucleotide Binding

Abstract In contrast to C5a, which represents a well-established potent activator of the respiratory burst in polymorphonuclear neutrophilic granulocytes (PMN), the functional role of C3a in the activation of PMN is, so far, poorly understood. Herein, the potential role of human C3a in the activation of the respiratory burst in human PMN was investigated. The release of reactive oxygen species (ROS) of PMN from healthy donors was measured by lucigenin-dependent chemiluminescence. C3a dose-dependently induced the production of ROS in human PMN in the range between 10 ng/mL and 1,000 ng/mL, whereas C3a-desArg was inactive. Flow cytometric measurement of H2O2 by dihydrorhodamine-123 labeling of anti-CD16-stained PMN showed that predominantly neutrophilic PMN are responsible for the C3a-induced activation of the respiratory burst. To exclude that C3a stimulation was caused by contamination with C5a, the specificity of C3a-induced activation of PMN was shown using monoclonal antibodies (MoAbs). Accordingly, the effect of C3a was completely abolished in the presence of Fab fragments of a blocking anti-C3a MoAb. In addition, blockade of the C5a receptor by the anti-C5a receptor (anti-C5aR) MoAb, S5/1, totally inhibited the C5a-induced production of ROS, whereas the C3a response in the presence of the anti-C5aR MoAb was unaffected. The specificity of the response was further confirmed by homologous desensitization after restimulation with C3a. In contrast, no cross-desensitization was observed upon stimulation with C5a. The C3a-induced ROS production by PMN was inhibited by pertussis toxin, indicating the involvement of guanine nucleotide-binding proteins (Gi proteins) in the signal transduction process initiated by C3a. In addition, stimulation of PMN by C3a resulted in a transient increase in the cytosolic free calcium concentration ([Ca2+]i) in a dose-dependent manner. In contrast to C3a- induced ROS production, C3a did not induce a chemotactic response in PMN, indicating functional qualitative differences as compared with C5a. In summary, these results show that C3a is a potent activator of the respiratory burst in human PMN. Therefore, these findings point to a novel role of C3a in the pathogenesis of inflammatory diseases associated with increased C3a levels and PMN activation.

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Hyperferritinaemia: An Iron Sword of Autoimmunity

Current Pharmaceutical Design ◽

10.2174/1381612825666190709202804 ◽

2019 ◽

Vol 25 (27) ◽

pp. 2909-2918 ◽

Cited By ~ 4

Author(s):

Joanna Giemza-Stokłosa ◽

Md. Asiful Islam ◽

Przemysław J. Kotyla

Keyword(s):

Immune Response ◽

Macrophage Activation ◽

Inflammatory Diseases ◽

Acute Phase Reactant ◽

Catastrophic Antiphospholipid Syndrome ◽

Inflammatory Conditions ◽

Phase Reactant ◽

Signalling Molecule ◽

Cytokine Synthesis

Background:: Ferritin is a molecule that plays many roles being the storage for iron, signalling molecule, and modulator of the immune response. Methods:: Different electronic databases were searched in a non-systematic way to find out the literature of interest. Results:: The level of ferritin rises in many inflammatory conditions including autoimmune disorders. However, in four inflammatory diseases (i.e., adult-onset Still’s diseases, macrophage activation syndrome, catastrophic antiphospholipid syndrome, and sepsis), high levels of ferritin are observed suggesting it as a remarkable biomarker and pathological involvement in these diseases. Acting as an acute phase reactant, ferritin is also involved in the cytokine-associated modulator of the immune response as well as a regulator of cytokine synthesis and release which are responsible for the inflammatory storm. Conclusion:: This review article presents updated information on the role of ferritin in inflammatory and autoimmune diseases with an emphasis on hyperferritinaemic syndrome.

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Role of Exosomes in the Exchange of Spermatozoa after Leaving the Seminiferous Tubule: A Review

Current Drug Metabolism ◽

10.2174/1389200221666200520091511 ◽

2020 ◽

Vol 21 (5) ◽

pp. 330-338

Author(s):

Luming Wu ◽

Yuan Ding ◽

Shiqiang Han ◽

Yiqing Wang

Keyword(s):

Drug Delivery ◽

Plasma Membrane ◽

Seminiferous Tubule ◽

Metabolic Diseases ◽

Inflammatory Diseases ◽

Multivesicular Bodies ◽

Extensive Search ◽

Neurological Research ◽

The One

Background: Exosomes are extracellular vesicles (EVs) released from cells upon fusion of an intermediate endocytic compartment with the plasma membrane. They refer to the intraluminal vesicles released from the fusion of multivesicular bodies with the plasma membrane. The contents and number of exosomes are related to diseases such as metabolic diseases, cancer and inflammatory diseases. Exosomes have been used in neurological research as a drug delivery tool and also as biomarkers for diseases. Recently, exosomes were observed in the seminal plasma of the one who is asthenozoospermia, which can affect sperm motility and capacitation. Objective: The main objective of this review is to deeply discuss the role of exosomes in spermatozoa after leaving the seminiferous tubule. Methods: We conducted an extensive search of the literature available on relationships between exosomes and exosomes in spermatozoa on the bibliographic database. Conclusion: : This review thoroughly discussed the role that exosomes play in the exchange of spermatozoa after leaving the seminiferous tubule and its potential as a drug delivery tool and biomarkers for diseases as well.

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The Immunomodulatory Role of G2013 (α-L-Guluronic Acid) on the Expression of TLR2 and TLR4 in HT29 cell line

Current Drug Discovery Technologies ◽

10.2174/1570163815666180226093711 ◽

2019 ◽

Vol 16 (1) ◽

pp. 91-95 ◽

Cited By ~ 4

Author(s):

Hamid Farhang ◽

Laleh Sharifi ◽

Mohammad Mehdi Soltan Dallal ◽

Mona Moshiri ◽

Zahra Norouzbabaie ◽

...

Keyword(s):

Inflammatory Responses ◽

Inflammatory Diseases ◽

Rna Extraction ◽

Cell Plate ◽

Inhibitory Effect ◽

Control Group ◽

Ht29 Cells ◽

Guluronic Acid ◽

Tlr4 Mrna

Background: The non-steroidal anti-inflammatory drugs (NSAIDs) play crucial role in the controlling of inflammatory diseases. Due to the vast side effects of NSAIDs, its use is limited. G2013 or &#945;-L-Guluronic Acid is a new NSAID with immunomodulatory features. Objectives: Considering the leading role of TLRs in inflammatory responses, in this study, we aimed to evaluate G2013 cytotoxicity and its effect on the expression of TLR2 and TLR4 molecules. Methods: HEK293-TLR2 and HEK293-TLR4 cells were cultured and seeded on 96-well cell plate, and MTT assay was performed for detecting the viability of the cells after treatment with different concentrations of G2013. HT29 cells were grown and treated with low and high doses of G2013. After total RNA extraction and cDNA synthesis, quantitative real-time PCR were performed to assess the TLR2 and TLR4 mRNA synthesis. Results: We found that concentrations of ≤125 &#181;g/ml of G2013 had no apparent cytotoxicity effect on the HEK293-TLR2 and -TLR4 cells. Our results indicated that after G2013 treatment (5 &#181;g/ml) in HT29 cells, TLR2 and TLR4 mRNA expression decreased significantly compared with the untreated control group (p=0.02 and p=0.001 respectively). Conclusion: The results of this study revealed that G2013 can down regulate the TLR2 and TLR4 gene expression and exerts its inhibitory effect. Our findings are parallel to our previous finding which showed G2013 ability to down regulate the signaling pathway of TLRs. However, further studies are needed to identify the molecular mechanism of G2013.<p>

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A family harboring an MLKL loss of function variant implicates impaired necroptosis in diabetes

Cell Death and Disease ◽

10.1038/s41419-021-03636-5 ◽

2021 ◽

Vol 12 (4) ◽

Author(s):

Joanne M. Hildebrand ◽

Bernice Lo ◽

Sara Tomei ◽

Valentina Mattei ◽

Samuel N. Young ◽

...

Keyword(s):

Potential Role ◽

Autosomal Dominant ◽

Inflammatory Diseases ◽

Diabetic Patients ◽

Incomplete Penetrance ◽

Loss Of Function ◽

Healthy Sibling ◽

Dominant Disease ◽

Terminal Effector

AbstractMaturity-onset diabetes of the young, MODY, is an autosomal dominant disease with incomplete penetrance. In a family with multiple generations of diabetes and several early onset diabetic siblings, we found the previously reported P33T PDX1 damaging mutation. Interestingly, this substitution was also present in a healthy sibling. In contrast, a second very rare heterozygous damaging mutation in the necroptosis terminal effector, MLKL, was found exclusively in the diabetic family members. Aberrant cell death by necroptosis is a cause of inflammatory diseases and has been widely implicated in human pathologies, but has not yet been attributed functions in diabetes. Here, we report that the MLKL substitution observed in diabetic patients, G316D, results in diminished phosphorylation by its upstream activator, the RIPK3 kinase, and no capacity to reconstitute necroptosis in two distinct MLKL−/− human cell lines. This MLKL mutation may act as a modifier to the P33T PDX1 mutation, and points to a potential role of impairment of necroptosis in diabetes. Our findings highlight the importance of family studies in unraveling MODY’s incomplete penetrance, and provide further support for the involvement of dysregulated necroptosis in human disease.

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The Role of Enterobacteriaceae in Gut Microbiota Dysbiosis in Inflammatory Bowel Diseases

Microorganisms ◽

10.3390/microorganisms9040697 ◽

2021 ◽

Vol 9 (4) ◽

pp. 697

Author(s):

Valerio Baldelli ◽

Franco Scaldaferri ◽

Lorenza Putignani ◽

Federica Del Chierico

Keyword(s):

Inflammatory Bowel Diseases ◽

Inflammatory Diseases ◽

Species Level ◽

Unknown Etiology ◽

Gut Dysbiosis ◽

Bowel Diseases ◽

Inflammatory Bowel ◽

Symbiotic Microbiota ◽

Gut Microbiota Dysbiosis

Inflammatory bowel diseases (IBDs) are a group of chronic gastrointestinal inflammatory diseases with unknown etiology. There is a combination of well documented factors in their pathogenesis, including intestinal microbiota dysbiosis. The symbiotic microbiota plays important functions in the host, and the loss of beneficial microbes could favor the expansion of microbial pathobionts. In particular, the bloom of potentially harmful Proteobacteria, especially Enterobacteriaceae, has been described as enhancing the inflammatory response, as observed in IBDs. Herein, we seek to investigate the contribution of Enterobacteriaceae to IBD pathogenesis whilst considering the continuous expansion of the literature and data. Despite the mechanism of their expansion still remaining unclear, their expansion could be correlated with the increase in nitrate and oxygen levels in the inflamed gut and with the bile acid dysmetabolism described in IBD patients. Furthermore, in several Enterobacteriaceae studies conducted at a species level, it has been suggested that some adherent-invasive Escherichia coli (AIEC) play an important role in IBD pathogenesis. Overall, this review highlights the pivotal role played by Enterobacteriaceae in gut dysbiosis associated with IBD pathogenesis and progression.

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The Enigma of Eosinophil Degranulation

International Journal of Molecular Sciences ◽

10.3390/ijms22137091 ◽

2021 ◽

Vol 22 (13) ◽

pp. 7091

Author(s):

Timothée Fettrelet ◽

Lea Gigon ◽

Alexander Karaulov ◽

Shida Yousefi ◽

Hans-Uwe Simon

Keyword(s):

Blood Cells ◽

Inflammatory Diseases ◽

White Blood Cells ◽

Exact Role ◽

Effector Cells ◽

Effector Functions ◽

Cytotoxic Effector ◽

Eosinophil Degranulation

Eosinophils are specialized white blood cells, which are involved in the pathology of diverse allergic and nonallergic inflammatory diseases. Eosinophils are traditionally known as cytotoxic effector cells but have been suggested to additionally play a role in immunomodulation and maintenance of homeostasis. The exact role of these granule-containing leukocytes in health and diseases is still a matter of debate. Degranulation is one of the key effector functions of eosinophils in response to diverse stimuli. The different degranulation patterns occurring in eosinophils (piecemeal degranulation, exocytosis and cytolysis) have been extensively studied in the last few years. However, the exact mechanism of the diverse degranulation types remains unknown and is still under investigation. In this review, we focus on recent findings and highlight the diversity of stimulation and methods used to evaluate eosinophil degranulation.

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Thiophene-Based Compounds with Potential Anti-Inflammatory Activity

Pharmaceuticals ◽

10.3390/ph14070692 ◽

2021 ◽

Vol 14 (7) ◽

pp. 692

Author(s):

Ryldene Marques Duarte da Cruz ◽

Francisco Jaime Bezerra Mendonça-Junior ◽

Natália Barbosa de Mélo ◽

Luciana Scotti ◽

Rodrigo Santos Aquino de Araújo ◽

...

Keyword(s):

Inflammatory Diseases ◽

Structural Characteristics ◽

Tiaprofenic Acid ◽

Inflammatory Activity ◽

Drug Candidates ◽

Biological Target ◽

Inflammatory Drugs ◽

Anti Inflammatory ◽

Privileged Structures

Rheumatoid arthritis, arthrosis and gout, among other chronic inflammatory diseases are public health problems and represent major therapeutic challenges. Non-steroidal anti-inflammatory drugs (NSAIDs) are the most prescribed clinical treatments, despite their severe side effects and their exclusive action in improving symptoms, without effectively promoting the cure. However, recent advances in the fields of pharmacology, medicinal chemistry, and chemoinformatics have provided valuable information and opportunities for development of new anti-inflammatory drug candidates. For drug design and discovery, thiophene derivatives are privileged structures. Thiophene-based compounds, like the commercial drugs Tinoridine and Tiaprofenic acid, are known for their anti-inflammatory properties. The present review provides an update on the role of thiophene-based derivatives in inflammation. Studies on mechanisms of action, interactions with receptors (especially against cyclooxygenase (COX) and lipoxygenase (LOX)), and structure-activity relationships are also presented and discussed. The results demonstrate the importance of thiophene-based compounds as privileged structures for the design and discovery of novel anti-inflammatory agents. The studies reveal important structural characteristics. The presence of carboxylic acids, esters, amines, and amides, as well as methyl and methoxy groups, has been frequently described, and highlights the importance of these groups for anti-inflammatory activity and biological target recognition, especially for inhibition of COX and LOX enzymes.

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Role of the IL33 and IL1RL1 pathway in the pathogenesis of Immunoglobulin A vasculitis

Scientific Reports ◽

10.1038/s41598-021-95762-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Diana Prieto-Peña ◽

Sara Remuzgo-Martínez ◽

Fernanda Genre ◽

Verónica Pulito-Cueto ◽

Belén Atienza-Mateo ◽

...

Keyword(s):

Inflammatory Diseases ◽

Disease Onset ◽

Immunoglobulin A ◽

Genetic Network ◽

Signalling Pathway ◽

Immune Mediated ◽

Increased Risk ◽

Genotype And Allele Frequencies ◽

Immunoglobulin A Vasculitis

AbstractCytokines signalling pathway genes are crucial factors of the genetic network underlying the pathogenesis of Immunoglobulin-A vasculitis (IgAV), an inflammatory vascular condition. An influence of the interleukin (IL)33- IL1 receptor like (IL1RL)1 signalling pathway on the increased risk of several immune-mediated diseases has been described. Accordingly, we assessed whether the IL33-IL1RL1 pathway represents a novel genetic risk factor for IgAV. Three tag polymorphisms within IL33 (rs3939286, rs7025417 and rs7044343) and three within IL1RL1 (rs2310173, rs13015714 and rs2058660), that also were previously associated with several inflammatory diseases, were genotyped in 380 Caucasian IgAV patients and 845 matched healthy controls. No genotypes or alleles differences were observed between IgAV patients and controls when IL33 and IL1RL1 variants were analysed independently. Likewise, no statistically significant differences were found in IL33 or IL1RL1 genotype and allele frequencies when IgAV patients were stratified according to the age at disease onset or to the presence/absence of gastrointestinal (GI) or renal manifestations. Similar results were disclosed when IL33 and IL1RL1 haplotypes were compared between IgAV patients and controls and between IgAV patients stratified according to the clinical characteristics mentioned above. Our results suggest that the IL33-IL1RL1 signalling pathway does not contribute to the genetic network underlying IgAV.

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