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Viruses May 2024Hepatitis B virus (HBV) is a major driver of chronic hepatic inflammation, which regularly leads to liver cirrhosis or hepatocellular carcinoma. Immediate innate immune...
Hepatitis B virus (HBV) is a major driver of chronic hepatic inflammation, which regularly leads to liver cirrhosis or hepatocellular carcinoma. Immediate innate immune cell response is crucial for the rapid clearance of the infection. Here, natural killer (NK) cells play a pivotal role in direct cytotoxicity and the secretion of antiviral cytokines as well as regulatory function. The aim of this study was to further elucidate NK cell responses triggered by an HBV infection. Therefore, we optimized HBV in vitro models that reliably stimulate NK cells using hepatocyte-like HepG2 cells expressing the Na-taurocholate co-transporting polypeptide (NTCP) and HepaRG cells. Immune cells were acquired from healthy platelet donors. Initially, HepG2-NTCP cells demonstrated higher viral replication compared to HepaRG cells. Co-cultures with immune cells revealed increased production of interferon-γ and tumor necrosis factor-α by NK cells, which was no longer evident in isolated NK cells. Likewise, the depletion of monocytes and spatial separation from target cells led to the absence of the antiviral cytokine production of NK cells. Eventually, the combined co-culture of isolated NK cells and monocytes led to a sufficient cytokine response of NK cells, which was also apparent when communication between the two immune cell subpopulations was restricted to soluble factors. In summary, our study demonstrates antiviral cytokine production by NK cells in response to HBV HepG2-NTCP cells, which is dependent on monocyte bystander activation.
Topics: Humans; Killer Cells, Natural; Monocytes; Hepatitis B virus; Cytokines; Coculture Techniques; Hep G2 Cells; Hepatitis B; Virus Replication; Interferon-gamma; Tumor Necrosis Factor-alpha; Hepatocytes
PubMed: 38793623
DOI: 10.3390/v16050741 -
International Journal of Molecular... May 2024Myocardial necrosis following the successful reperfusion of a coronary artery occluded by thrombus in a patient presenting with ST-elevation myocardial infarction... (Review)
Review
Initial Despair and Current Hope of Identifying a Clinically Useful Treatment of Myocardial Reperfusion Injury: Insights Derived from Studies of Platelet P2Y Antagonists and Interference with Inflammation and NLRP3 Assembly.
Myocardial necrosis following the successful reperfusion of a coronary artery occluded by thrombus in a patient presenting with ST-elevation myocardial infarction (STEMI) continues to be a serious problem, despite the multiple attempts to attenuate the necrosis with agents that have shown promise in pre-clinical investigations. Possible reasons include confounding clinical risk factors, the delayed application of protective agents, poorly designed pre-clinical investigations, the possible effects of routinely administered agents that might unknowingly already have protected the myocardium or that might have blocked protection, and the biological differences of the myocardium in humans and experimental animals. A better understanding of the pathobiology of myocardial infarction is needed to stem this reperfusion injury. P2Y receptor antagonists minimize platelet aggregation and are currently part of the standard treatment to prevent thrombus formation and propagation in STEMI protocols. Serendipitously, these P2Y antagonists also dramatically attenuate reperfusion injury in experimental animals and are presumed to provide a similar protection in STEMI patients. However, additional protective agents are needed to further diminish reperfusion injury. It is possible to achieve additive protection if the added intervention protects by a mechanism different from that of P2Y antagonists. Inflammation is now recognized to be a critical factor in the complex intracellular response to ischemia and reperfusion that leads to tissue necrosis. Interference with cardiomyocyte inflammasome assembly and activation has shown great promise in attenuating reperfusion injury in pre-clinical animal models. And the blockade of the executioner protease caspase-1, indeed, supplements the protection already seen after the administration of P2Y antagonists. Importantly, protective interventions must be applied in the first minutes of reperfusion, if protection is to be achieved. The promise of such a combination of protective strategies provides hope that the successful attenuation of reperfusion injury is attainable.
Topics: Myocardial Reperfusion Injury; Humans; Purinergic P2Y Receptor Antagonists; Animals; NLR Family, Pyrin Domain-Containing 3 Protein; Inflammation; Receptors, Purinergic P2Y12
PubMed: 38791515
DOI: 10.3390/ijms25105477 -
Biomedicines May 2024Acute myocardial infarction (AMI) is one of the leading causes of death worldwide. Cell apoptosis in the myocardium plays an important role in ischemia and reperfusion...
Acute myocardial infarction (AMI) is one of the leading causes of death worldwide. Cell apoptosis in the myocardium plays an important role in ischemia and reperfusion (I/R) injury, leading to cardiac damage and dysfunction. Platelets are major players in hemostasis and play a crucial role in vessel occlusion, inflammation, and cardiac remodeling after I/R. Here, we studied the impact of platelets on cell apoptosis in the myocardium using a close-chest mouse model of AMI. We found caspase-3-positive resident cardiac cells, while leukocytes were negative for caspase-3. Using two different mouse models of thrombocytopenia, we detected a significant reduction in caspase-3 positive cells in the infarct border zone after I/R injury. Further, we identified platelet FasL to induce cell apoptosis via the extrinsic pathway of Fas receptor activation of target cells. Mechanistically, hypoxia triggers platelet adhesion to FasR, suggesting that platelet-induced apoptosis is elevated after I/R. Platelet-specific FasL knock-out mice showed reduced and expression, suggesting that platelets modulate the intrinsic and extrinsic pathways of apoptosis, leading to reduced infarct size after myocardial I/R injury. Thus, a new mechanism for how platelets contribute to tissue homeostasis after AMI was identified that should be validated in patients soon.
PubMed: 38791039
DOI: 10.3390/biomedicines12051077 -
Genes May 2024A recently discovered haplotype--determines the ultrarapid metabolism of several CYP2C19 substrates. The platelet inhibitor clopidogrel requires CYP2C19-mediated...
A recently discovered haplotype--determines the ultrarapid metabolism of several CYP2C19 substrates. The platelet inhibitor clopidogrel requires CYP2C19-mediated activation: the risk of ischemic events is increased in patients with a poor (PM) or intermediate (IM) CYP2C19 metabolizer phenotype (vs. normal, NM; rapid, RM; or ultrarapid, UM). We investigated whether the haplotype affected efficacy/bleeding risk in clopidogrel-treated patients. Adults ( = 283) treated with clopidogrel over 3-6 months were classified by CYP2C19 phenotype based on the genotype, and based on the cluster genotype, and regarding carriage of the haplotype, and were balanced on a number of covariates across the levels of phenotypes/haplotype carriage. Overall, 45 (15.9%) patients experienced ischemic events, and 49 (17.3%) experienced bleedings. By either classification, the incidence of ischemic events was similarly numerically higher in PM/IM patients (21.6%, 21.8%, respectively) than in mutually similar NM, RM, and UM patients (13.2-14.8%), whereas the incidence of bleeding events was numerically lower (13.1% vs. 16.6-20.5%). The incidence of ischemic events was similar in carries and non-carries (14.1% vs. 16.1%), whereas the incidence of bleedings appeared mildly lower in the former (14.9% vs. 20.1%). We observed no signal to suggest a major effect of the cluster genotype or haplotype on the clinical efficacy/safety of clopidogrel.
Topics: Humans; Clopidogrel; Haplotypes; Male; Female; Cytochrome P-450 CYP2C19; Hemorrhage; Aged; Middle Aged; Platelet Aggregation Inhibitors; Genotype; Ticlopidine
PubMed: 38790236
DOI: 10.3390/genes15050607 -
Biomedicine & Pharmacotherapy =... Jul 2024Activation of neuropilin-1 (NRP-1) by platelet derived growth factor (PDGF)-C sustains melanoma invasiveness. Therefore, in the search of novel agents capable of...
Activation of neuropilin-1 (NRP-1) by platelet derived growth factor (PDGF)-C sustains melanoma invasiveness. Therefore, in the search of novel agents capable of reducing melanoma spreading, PDGF-C/NRP-1 interaction was investigated as a potential druggable target. Since the PDGF-C region involved in NRP-1 binding is not yet known, based on the sequence and structural homology between PDGF-C and vascular endothelial growth factor-A (VEGF-A), we hypothesized that the NRP-1 b1 domain region involved in the interaction with VEGF-A might also be required for PDGF-C binding. Hence, this region was selected from the protein crystal structure and used as target in the molecular docking procedure. In the following virtual screening, compounds from a DrugBank database were used as query ligands to identify agents potentially capable of disrupting NRP-1/PDGF-C interaction. Among the top 45 candidates with the highest affinity, five drugs were selected based on the safety profile, lack of hormonal effects, and current availability in the market: the antipsychotic pimozide, antidiabetic gliclazide, antiallergic cromolyn sodium, anticancer tyrosine kinase inhibitor entrectinib, and antihistamine azelastine. Analysis of drug influence on PDGF-C in vitro binding to NRP-1 and PDGF-C induced migration of human melanoma cells expressing NRP-1, indicated gliclazide and entrectinib as the most specific agents that were active at clinically achievable and non-toxic concentrations. Both drugs also reverted PDGF-C ability to stimulate extracellular matrix invasion by melanoma cells resistant to BRAF inhibitors. The inhibitory effect on tumor cell motility involved a decrease of p130Cas phosphorylation, a signal transduction pathway activated by PDGF-C-mediated stimulation of NRP-1.
Topics: Humans; Melanoma; Lymphokines; Platelet-Derived Growth Factor; Neuropilin-1; Molecular Docking Simulation; Cell Line, Tumor; Protein Binding; Cell Movement; Neoplasm Metastasis; Antineoplastic Agents
PubMed: 38788599
DOI: 10.1016/j.biopha.2024.116766 -
Cells May 2024Patients with COVID-19 have coagulation and platelet disorders, with platelet alterations and thrombocytopenia representing negative prognostic parameters associated...
UNLABELLED
Patients with COVID-19 have coagulation and platelet disorders, with platelet alterations and thrombocytopenia representing negative prognostic parameters associated with severe forms of the disease and increased lethality.
METHODS
The aim of this study was to study the expression of platelet glycoprotein IIIa (CD61), playing a critical role in platelet aggregation, together with TRL-2 as a marker of innate immune activation.
RESULTS
A total of 25 patients were investigated, with the majority (24/25, 96%) having co-morbidities and dying from a fatal form of SARS-CoV-2(+) infection (COVID-19+), with 13 men and 12 females ranging in age from 45 to 80 years. When compared to a control group of SARS-CoV-2 (-) negative lungs (COVID-19-), TLR-2 expression was up-regulated in a subset of patients with deadly COVID-19 fatal lung illness. The proportion of Spike-1 (+) patients found by PCR and ISH correlates to the proportion of Spike-S1-positive cases as detected by digital pathology examination. Furthermore, CD61 expression was considerably higher in the lungs of deceased patients. In conclusion, we demonstrate that innate immune prolonged hyperactivation is related to platelet/megakaryocyte over-expression in the lung.
CONCLUSIONS
Microthrombosis in deadly COVID-19+ lung disease is associated with an increase in the number of CD61+ platelets and megakaryocytes in the pulmonary interstitium, as well as their functional activation; this phenomenon is associated with increased expression of innate immunity TLR2+ cells, which binds the SARS-CoV-2 E protein, and significantly with the persistence of the Spike-S1 viral sequence.
Topics: Humans; COVID-19; Male; Female; Toll-Like Receptor 2; Megakaryocytes; Aged; Middle Aged; SARS-CoV-2; Aged, 80 and over; Lung; Up-Regulation; Thrombosis; Integrin beta3; Spike Glycoprotein, Coronavirus; Pneumonia, Viral; Immunity, Innate; Pandemics
PubMed: 38786077
DOI: 10.3390/cells13100854 -
Pediatric Rheumatology Online Journal May 2024Macrophage activation syndrome (MAS), an example of secondary hemophagocytic lymphohistiocytosis, is a potentially fatal complication of rheumatic diseases. We aimed to...
BACKGROUND
Macrophage activation syndrome (MAS), an example of secondary hemophagocytic lymphohistiocytosis, is a potentially fatal complication of rheumatic diseases. We aimed to study the clinical and laboratory characteristics, treatment schemes, and outcomes of different rheumatic disorders associated with MAS in children. Early warning indicators of MAS have also been investigated to enable clinicians to make a prompt and accurate diagnosis.
METHODS
Fifty-five patients with rheumatic diseases complicated by MAS were enrolled between January 2017 and December 2022. Clinical and laboratory data were collected before disease onset, at diagnosis, and after treatment with MAS, and data were compared between patients with systemic juvenile idiopathic arthritis (sJIA), Kawasaki disease (KD), and systemic lupus erythematosus (SLE). A random forest model was established to show the importance score of each variable with a significant difference.
RESULTS
Most (81.8%) instances of MAS occurred during the initial diagnosis of the underlying disease. Compared to the active stage of sJIA, the platelet count, erythrocyte sedimentation rate, and fibrinogen level in sJIA-MAS were significantly decreased, whereas ferritin, ferritin/erythrocyte sedimentation rate, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, and D-dimer levels were significantly increased. Ferritin level, ferritin/erythrocyte sedimentation rate, and platelet count had the greatest predictive value for sJIA-MAS. The level of IL-18 in the sJIA-MAS group was significantly higher than in the active sJIA group, whereas IL-6 levels were significantly lower. Most patients with MAS were treated with methylprednisolone pulse combined with cyclosporine, and no deaths occurred.
CONCLUSIONS
Thrombocytopenia, ferritin levels, the ferritin/erythrocyte sedimentation rate, and elevated aspartate aminotransferase levels can predict the occurrence of MAS in patients with sJIA. Additionally, our analysis indicates that IL-18 plays an important role in the pathogenesis of MAS in sJIA-MAS.
Topics: Humans; Macrophage Activation Syndrome; Male; Female; Child; Arthritis, Juvenile; Child, Preschool; Adolescent; Ferritins; Lupus Erythematosus, Systemic; Blood Sedimentation; Retrospective Studies; Platelet Count; Mucocutaneous Lymph Node Syndrome
PubMed: 38783316
DOI: 10.1186/s12969-024-00991-3 -
PloS One 2024This study aimed to evaluate the intervention effect of curcumin on hepatic fibrosis in rodent models through systematic review and meta-analysis, in order to provide... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
This study aimed to evaluate the intervention effect of curcumin on hepatic fibrosis in rodent models through systematic review and meta-analysis, in order to provide meaningful guidance for clinical practice.
METHODS
A systematic retrieval of relevant studies on curcumin intervention in rats or mice hepatic fibrosis models was conducted, and the data were extracted. The outcome indicators included liver cell structure and function related indicators, such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), albumin (ALB), ratio of albumin to globulin (A/G), total bilirubin (TBIL), bax protein, bcl-2 protein and index of liver, as well as the relevant indicators for evaluating the degree of hepatic fibrosis, such as hyaluronic acid (HA), laminin (LN), type I collagen (Collagen I), type III collagen (Collagen III), type III procollagen (PCIII), type III procollagen amino terminal peptide (PIIINP), type IV collagen (IV-C), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), α-Smooth muscle actin (α-SMA), hydroxyproline (HYP), platelet derived factor-BB (PDGF-BB), connective tissue growth factor (CTGF) and transforming growth factor-β1 (TGF-β1), and oxidative stress-related indicators, such as superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione peroxidase (GSH-Px). These results were then analyzed by meta-analysis. Studies were evaluated for methodological quality using the syrcle's bias risk tool.
RESULTS
A total of 59 studies were included in the meta-analysis, and the results showed that curcumin can reduce the levels of ALT, AST, ALP, TBIL, bax protein, and index of liver in hepatic fibrosis models. It can also reduce HA, LN, Collagen I, Collagen III, PCIII, PIIINP, IV-C, TNF-α, α-SMA, HYP, PDGF-BB, CTGF, TGF-β1 and MDA, and increase the levels of ALB, A/G, SOD, and GSH-Px in the hepatic fibrosis models. However, the effects of curcumin on bcl-2 protein, IL-6 in hepatic fibrosis models and index of liver in mice were not statistically significant.
CONCLUSION
The analysis results indicate that curcumin can reduce liver cell apoptosis by maintaining the stability of liver cell membrane, inhibit the activation and proliferation of hepatic stellate cells by reducing inflammatory response, and alleviate tissue peroxidation damage by clearing oxygen free radicals.
Topics: Animals; Liver Cirrhosis; Curcumin; Mice; Rats; Disease Models, Animal; Oxidative Stress; Liver
PubMed: 38781262
DOI: 10.1371/journal.pone.0304176 -
The Journal of Pharmacology and... May 2024Bi-directional signaling through platelet integrin αβ is essential in hemostasis and thrombosis. In quiescent platelets αβ is in a low-affinity ligand binding state....
Bi-directional signaling through platelet integrin αβ is essential in hemostasis and thrombosis. In quiescent platelets αβ is in a low-affinity ligand binding state. However, upon platelet activation by agonists through inside-out signaling, a rapid switch in the conformation of the integrin results in a high affinity ligand binding state capable of binding soluble fibrinogen. Ligand binding to the αβ induces a signaling termed outside-in signaling that regulate platelet spreading and clot retraction. These events are often interchangeably used to represent outside-in signaling pathway. Using pharmacological inhibitors of known signaling molecules that have been implicated to regulate outside-in signaling, we assessed human platelet spreading and clot retraction. We found that inhibition of PI3K, PLC, PKC, and FAK strongly attenuated both platelet spreading and clot retraction suggesting that they are essential for both clot retraction and platelet spreading. Whereas inhibition of Rac1, ROCK, p38, and MEK did not affect platelet spreading but significantly delayed clot retraction suggesting that these signaling molecules do not participate in platelet spreading. Interestingly, Src family kinases (SFKs) are required for platelet spreading and FAK activation but suppresses clot retraction since their inhibition causes faster clot retraction. Thus, it becomes evident that platelet spreading, and clot retraction are differently regulated through αβ outside-in signaling and should not be used interchangeably as readout for αβ outside-in signaling assessment. Current anti-platelet drugs have increased risk of bleeding and low efficacy. There is an increased effort to identify novel anti-platelet agents that have improved efficacy with reduced risk of bleeding. It is increasingly felt that inhibition of αβinduced outside-in signaling may inhibit thrombosis without compromising hemostasis. However, the signaling entities regulating outside-in signaling is poorly understood. Our work included in this manuscript delineates the distinct signaling pathways involved in outside-in signaling and identify potential novel targets for intervention of thrombosis.
PubMed: 38777606
DOI: 10.1124/jpet.124.002149 -
Arteriosclerosis, Thrombosis, and... Jun 2024
Review
Topics: Blood Platelets; Humans; Inflammation; Thrombosis; Animals; Platelet Activation; Inflammation Mediators; Signal Transduction
PubMed: 38776384
DOI: 10.1161/ATVBAHA.124.320149