Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 1.081
Filter
1.
Cytokine ; 178: 156592, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38574505

ABSTRACT

The severity of COVID-19 has been reported to differ among SARS-CoV-2 mutant variants. The overactivation of macrophages is involved in severe COVID-19, yet the effects of SARS-CoV-2 mutations on macrophages remain poorly understood. To clarify the effects, we examined whether mutations of spike proteins (S-proteins) affect macrophage activation. CD14+ monocyte-derived macrophages were stimulated with the recombinant S-protein of the wild-type, Delta, and Omicron strains or live viral particles of individual strains. Regarding IL-6 and TNF-α, Delta or Omicron S-protein had stronger or weaker pro­inflammatory ability, respectively, than the wild-type. Similar trends were observed between S-proteins and viral particles. S-protein mutations could be related to the diversity in macrophage activation and severity rates in COVID-19 caused by various SARS-CoV-2 strains.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Spike Glycoprotein, Coronavirus/genetics , Ataxia Telangiectasia Mutated Proteins
2.
J Int Med Res ; 52(4): 3000605241240579, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38603605

ABSTRACT

The mortality rate of gastric varices bleeding can reach 20% within 6 weeks. Isolated gastric varices (IGVs) refer to gastric varices without esophageal varices and typically arise as a common complication of left portal hypertension. Although IGVs commonly form in the setting of splenic vein occlusion, the combination of antiphospholipid syndrome and protein S deficiency leading to splenic vein occlusion is rare. We herein present a case of a 28-year-old woman with intermittent epigastric pain and melena. She was diagnosed with antiphospholipid syndrome based on the triad of pregnancy morbidity, unexplained venous occlusion, and positive lupus anticoagulant. Laparoscopic splenectomy and pericardial devascularization were performed for the treatment of IGVs. During the 6-month postoperative follow-up, repeated endoscopy and contrast-enhanced computed tomography revealed disappearance of the IGVs. This is the first description of splenic vein occlusion associated with both antiphospholipid syndrome and protein S deficiency. We also provide a review of the etiology, clinical manifestations, diagnosis, and treatment methods of IGVs.


Subject(s)
Antiphospholipid Syndrome , Esophageal and Gastric Varices , Protein S Deficiency , Vascular Diseases , Female , Humans , Adult , Esophageal and Gastric Varices/complications , Esophageal and Gastric Varices/diagnosis , Antiphospholipid Syndrome/complications , Antiphospholipid Syndrome/diagnosis , Protein S Deficiency/complications , Gastrointestinal Hemorrhage/etiology , Vascular Diseases/complications
3.
J Hematol ; 13(1-2): 23-28, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38644988

ABSTRACT

Background: ß-thalassemia is a group of inherited blood disorders that affect the production of ß-globin chains, leading to the reduction or absence of these chains. One of the complications observed in patients with ß-thalassemia major (ß-TM) is thrombosis, especially in those who receive frequent blood transfusions. This may be due to a decrease in the levels of the natural anticoagulants: protein C (PC), total protein S (PS), and antithrombin (AT). Methods: In this case-control study, patients with ß-TM, who had received at least 20 packed cell transfusions during their lifetime, were included. Patients with other underlying diseases like bleeding or thrombotic disorders were excluded. Totally, 118 patients with ß-TM and 120 healthy individuals were included. Results: The mean level of PC and AT was significantly lower in patients with ß-TM (48.2 ± 65.4 and 57.42 ± 13.6, respectively) compared to the control group (97.1 ± 21.46 and 81.79 ± 14.3, respectively), with P value of 0.001 and 0.01, respectively. Although the difference was not statistically significant (P = 0.1), a similar trend was observed for total PS (61.12 ± 21.12 for patients versus 72.2 ± 35.2 for the control group). Of note, the decrease in PC, AT, and total PS levels compared to the control group was 50.36%, 27.5%, and 15.34%, respectively. Conclusions: It seems that ß-TM patients who receive prolonged blood transfusions frequently are at an increased risk of decreased in natural anticoagulants levels and therefore potentially are at risk of thrombosis.

4.
Platelets ; 35(1): 2337907, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38602463

ABSTRACT

Protein S (PS) is a vital endogenous anticoagulant. It plays a crucial role in regulating coagulation by acting as a cofactor for the activated protein C (APC) and tissue factor pathway inhibitor (TFPI) pathways. Additionally, it possesses direct anticoagulant properties by impeding the intrinsic tenase and prothrombinase complexes. Protein S oversees the coagulation process in both the initiation and propagation stages through these roles. The significance of protein S in regulating blood clotting can be inferred from the significant correlation between deficits in protein S and an elevated susceptibility to venous thrombosis. This is likely because activated protein C and tissue factor pathway inhibitor exhibit low efficacy as anticoagulants when no cofactors exist. The precise biochemical mechanisms underlying the roles of protein S cofactors have yet to be fully elucidated. Nevertheless, recent scientific breakthroughs have significantly enhanced comprehension findings for these functions. The diagnosis of protein S deficiency, both from a technical and genetic standpoint, is still a subject of debate due to the complex structural characteristics of the condition. This paper will provide an in-depth review of the molecular structure of protein S and its hemostatic effects. Furthermore, we shall address the insufficiency of protein S and its methods of diagnosis and treatment.


What is the purpose of this summary? To provide an in-depth review of the molecular structure of protein S and its hemostatic effects.To address the deficiency of protein S and its methods of diagnosis and treatment.What is known? Protein S operates as an anticoagulant through its roles as a cofactor for APC, TFPI, and an inhibitor of FIXa.Protein S deficiency can be either inherited or acquired.What is new? Plasma protein S and platelet-derived protein S contribute to regulating coagulation and maintaining hemostasis. Protein S can be used as a potential promising treatment target for persons diagnosed with hemophilia.


Subject(s)
Anticoagulants , Hemostatics , Humans , Anticoagulants/pharmacology , Anticoagulants/therapeutic use , Protein C , Blood Coagulation
5.
Stress Biol ; 4(1): 23, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38662136

ABSTRACT

Geminiviruses are an important group of viruses that infect a variety of plants and result in heavy agricultural losses worldwide. The homologs of C4 (or L4) in monopartite geminiviruses and AC4 (or AL4) in bipartite geminiviruses are critical viral proteins. The C4 proteins from several geminiviruses are the substrates of S-acylation, a dynamic post-translational modification, for the maintenance of their membrane localization and function in virus infection. Here we initiated a screening and identified a plant protein ABAPT3 (Alpha/Beta Hydrolase Domain-containing Protein 17-like Acyl Protein Thioesterase 3) as the de-S-acylation enzyme of C4 encoded by BSCTV (Beet severe curly top virus). Overexpression of ABAPT3 reduced the S-acylation of BSCTV C4, disrupted its plasma membrane localization, inhibited its function in pathogenesis, and suppressed BSCTV infection. Because the S-acylation motifs are conserved among C4 from different geminiviruses, we tested the effect of ABAPT3 on the C4 protein of ToLCGdV (Tomato leaf curl Guangdong virus) from another geminivirus genus. Consistently, ABAPT3 overexpression also disrupted the S-acylation, subcellular localization, and function of ToLCGdV C4, and inhibited ToLCGdV infection. In summary, we provided a new approach to globally improve the resistance to different types of geminiviruses in plants via de-S-acylation of the viral C4 proteins and it can be extendedly used for suppression of geminivirus infection in crops.

6.
Eur J Immunol ; : e2350825, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38650034

ABSTRACT

Cyclosporin A is a well-established immunosuppressive drug used to treat or prevent graft-versus-host disease, the rejection of organ transplants, autoimmune disorders, and leukemia. It exerts its immunosuppressive effects by inhibiting calcineurin-mediated dephosphorylation of the nuclear factor of activated T cells (NFAT), thus preventing its nuclear entry and suppressing T cell activation. Here we report an unexpected immunostimulatory effect of cyclosporin A in activating the mammalian target of rapamycin complex 1 (mTORC1), a crucial metabolic hub required for T cell activation. Through screening a panel of tool compounds known to regulate mTORC1 activation, we found that cyclosporin A activated mTORC1 in CD8+ T cells in a 3-phosphoinositide-dependent protein kinase 1 (PDK1) and protein kinase B (PKB/AKT)-dependent manner. Mechanistically, cyclosporin A inhibited the calcineurin-mediated AKT dephosphorylation, thereby stabilizing mTORC1 signaling. Cyclosporin A synergized with mTORC1 pathway inhibitors, leading to potent suppression of proliferation and cytokine production in CD8+ T cells and an increase in the killing of acute T cell leukemia cells. Consequently, relying solely on CsA is insufficient to achieve optimal therapeutic outcomes. It is necessary to simultaneously target both the calcineurin-NFAT pathway and the mTORC1 pathway to maximize therapeutic efficacy.

7.
Article in English | MEDLINE | ID: mdl-38584071

ABSTRACT

BACKGROUND: Efficient classification of T-acute lymphoblastic leukemia (T-ALL) involves considering various factors, such as age, white blood cell count, and chromosomal alterations. However, studying protein markers are crucial to improving T-ALL patients' diagnosis and treatment. A study analyzing the expression of proteomes was conducted to identify promising early-stage biomarkers for T-ALL patients METHODS: Label-free liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to analyze the blood proteins of both patients and healthy individuals to identify new biomarkers for T-ALL. The findings were validated by RT-PCR, ELISA and computational analysis RESULTS: The study identified 1467 proteins in the blood, of which nine were upregulated and 35 were downregulated by more than 2-fold. T-ALL patients showed a significant increase in specific disease-related proteins, such as eleven-nineteen lysine-rich leukemia protein, triggering receptor expressed on myeloid cells 1, cisplatin resistance-associated-overexpressed protein, X-ray radiation resistance-associated protein 1, tumor necrosis factor receptor superfamily member 10D, protein S100-A8, and copine-4, by more than 3-fold CONCLUSION: The findings of this study provide a valuable protein map of leukemic cells and identify potential biomarkers for leukemic aggressiveness. However, further studies using larger T-ALL patient samples must confirm these preliminary results.

8.
Radiol Case Rep ; 19(6): 2249-2252, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38532907

ABSTRACT

Autoimmune diseases and thrombophilic disorders, notably antiphospholipid syndrome (APS) and protein S deficiency, present a formidable challenge in pregnancy, substantially increasing the risk of thromboembolic complications by up to 20%. Pulmonary thromboembolism (PTE), characterized by a significantly higher maternal mortality rate, is of particular concern. APS, defined by the presence of antiphospholipid antibodies, emerges as a pivotal risk factor for PTE during pregnancy, especially in women exhibiting triple negativity. Concurrently, protein S deficiency further amplifies vulnerability to thromboembolic events, establishing a high-risk scenario for pregnant individuals. In a case involving a 29-year-old pregnant woman with a history of generalized lupus erythematosus, triple-negative antiphospholipid syndrome, and protein S deficiency, sudden-onset dyspnea prompted thorough investigation. Despite her complex medical history, a multidisciplinary approach led to the accurate diagnosis and successful management of subsegmental pulmonary thromboembolism, ensuring the well-being of both mother and fetus. Effectively managing PTE during pregnancy demands a comprehensive, multidisciplinary approach involving collaboration among obstetricians, internists, rheumatologists, and hematologists. Accurate diagnosis, tailored anticoagulation strategies, and continuous monitoring stand as indispensable pillars for maternal and fetal well-being.

9.
Transfus Apher Sci ; : 103918, 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38555232

ABSTRACT

INTRODUCTION: Therapeutic plasma exchange (TPE), with solvent/detergent (S/D)-treated plasma as replacement fluid, is an extracorporeal blood purification technique with major impact on both coagulation and lipids. Our previous in vitro study showed that S/D-plasma enhances thrombin generation by lowering intact protein S (PS) levels. AIMS: To evaluate the impact of altered lipid balance on coagulation phenotype during heparin-anticoagulated TPE with S/D-plasma, and to investigate whether the lowered intact PS levels with concomitant procoagulant phenotype, are recapitulated in vivo. METHODS: Coagulation biomarkers, thrombin generation with Calibrated Automated Thrombogram (CAT), and lipid levels were measured before and after the consecutive 1st, 3rd and 5th episodes of TPE performed to six patients with Guillain-Barré syndrome or myasthenia gravis. The effects of in vitro dilution of S/D-plasma on thrombin generation were explored with CAT to mimic TPE. RESULTS: Patients did not have coagulation disorders, except elevated FVIII. Intact PS, lipoproteins, especially LDL, Apolipoprotein CIII (ApoC3) and ApoB/ApoA1 ratio declined (p < 0.05). In contrast, VLDL and triglyceride levels stayed intact. CAT lag time shortened (p < 0.05). In vitro dilution of S/D plasma with co-transfused Ringer's lactate and 4% albumin partially reduced its procoagulant phenotype in CAT, which is mainly seen as peak thrombin, and modestly shortened lag time. CONCLUSIONS: After the five settings of TPE using S/D-plasma in vivo, which associated with heparinization and reduced coagulation factor activities, our observations of declining natural anticoagulant intact PS and apolipoproteins refer to rebalance of the hemostatic and lipid profiles.

10.
Int J Mol Sci ; 25(6)2024 Mar 16.
Article in English | MEDLINE | ID: mdl-38542343

ABSTRACT

The TAMs are a subfamily of receptor tyrosine kinases (RTKs) comprised of three members, Tyro3, Axl and Mer. Evidence in support of the existence of this subfamily emerged from a screen for novel RTKs performed in the laboratory of Dr. Greg Lemke in 1991. A PCR-based approach to selectively amplify tyrosine kinase-specific genes yielded 27 different tyrosine kinase genes, of which 13 were novel (the "Tyros"). Of these, Tyro3, 7 and 12 were more closely related to each other than to any other kinases and it was proposed that they constituted a novel subfamily of RTKs. Additional support for this hypothesis required determining the complete sequences for these receptor tyrosine kinases. By the end of 1991, full-length sequences for Tyro7 (Axl) revealed a unique extracellular domain organization that included two immunoglobulin-like domains and two fibronectin type III repeats. In 1994, the complete sequences for Tyro12 (Mer) and Tyro3 were shown to have an extracellular region domain structure similar to that of Axl. In 1995, Gas6 and Pros1 were reported as ligands for Tyro3 and Axl, setting the stage for functional studies. The Lemke lab and its many trainees have since played leading roles in elucidating the physiological relevance of the TAMs.


Subject(s)
Axl Receptor Tyrosine Kinase , Proto-Oncogene Proteins , c-Mer Tyrosine Kinase/genetics , Proto-Oncogene Proteins/genetics , Receptor Protein-Tyrosine Kinases/genetics , Receptor Protein-Tyrosine Kinases/chemistry , Tamoxifen , Tyrosine
11.
Ticks Tick Borne Dis ; 15(4): 102333, 2024 Mar 23.
Article in English | MEDLINE | ID: mdl-38522220

ABSTRACT

Rhipicephalus (Boophilus) microplus, also known as the cattle tick, causes severe parasitism and transmits different pathogens to vertebrate hosts, leading to massive economic losses. In the present study, we performed a functional characterization of a ribosomal protein from R. microplus to investigate its importance in blood feeding, egg production and viability. Ribosomal protein S18 (RPS18) is part of the 40S subunit, associated with 18S rRNA, and has been previously pointed to have a secondary role in different organisms. Rhipicephalus microplus RPS18 (RmRPS18) gene expression levels were modulated in female salivary glands during blood feeding. Moreover, mRNA levels in this tissue were 10 times higher than those in the midgut of fully engorged female ticks. Additionally, recombinant RmRPS18 was recognized by IgG antibodies from sera of cattle naturally or experimentally infested with ticks. RNAi-mediated knockdown of the RmRPS18 gene was performed in fully engorged females, leading to a significant (29 %) decrease in egg production. Additionally, egg hatching was completely impaired, suggesting that no viable eggs were produced by the RmRPS18-silenced group. Furthermore, antimicrobial assays revealed inhibitory activities against gram-negative Escherichia coli and gram-positive Staphylococcus aureus bacteria, affecting bacterial growth. Data presented here show the important role of RmRPS18 in tick physiology and suggest that RmRPS18 can be a potential target for the development of novel strategies for tick control.

12.
Comput Biol Med ; 172: 108204, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38484695

ABSTRACT

S6K2 is an important protein in mTOR signaling pathway and cancer. To identify potential S6K2 inhibitors for mTOR pathway treatment, a virtual screening of 1,575,957 active molecules was performed using PLANET, AutoDock GPU, and AutoDock Vina, with their classification abilities compared. The MM/PB(GB)SA method was used to identify four compounds with the strongest binding energies. These compounds were further investigated using molecular dynamics (MD) simulations to understand the properties of the S6K2/ligand complex. Due to a lack of available 3D structures of S6K2, OmegaFold served as a reliable 3D predictive model with higher evaluation scores in SAVES v6.0 than AlphaFold, AlphaFold2, and RoseTTAFold2. The 150 ns MD simulation revealed that the S6K2 structure in aqueous solvation experienced compression during conformational relaxation and encountered potential energy traps of about 19.6 kJ mol-1. The virtual screening results indicated that Lys75 and Lys99 in S6K2 are key binding sites in the binding cavity. Additionally, MD simulations revealed that the ligands remained attached to the activation cavity of S6K2. Among the compounds, compound 1 induced restrictive dissociation of S6K2 in the presence of a flexible region, compound 8 achieved strong stability through hydrogen bonding with Lys99, compound 9 caused S6K2 tightening, and the binding of compound 16 was heavily influenced by hydrophobic interactions. This study suggests that these four potential inhibitors with different mechanisms of action could provide potential therapeutic options.


Subject(s)
Ribosomal Protein S6 Kinases, 70-kDa , TOR Serine-Threonine Kinases , Phosphorylation , Ribosomal Protein S6 Kinases, 70-kDa/metabolism , TOR Serine-Threonine Kinases/metabolism , Computers
14.
J Gastrointest Oncol ; 15(1): 220-236, 2024 Feb 29.
Article in English | MEDLINE | ID: mdl-38482222

ABSTRACT

Background: Colorectal cancer is one of the top five malignant tumors in the world in terms of morbidity and mortality. Numerous long non-coding RNAs (lncRNAs) are specifically expressed in tumours and can affect various types of human cancer by participating in competitive endogenous RNA (ceRNA) regulatory networks. However, the specific mechanisms and complex networks of ceRNA regulatory patterns in colon adenocarcinoma (COAD) remain unclear. Methods: Using The Cancer Genome Atlas (TCGA) database, we identified the differentially expressed lncRNA, microRNA (miRNA), and messenger RNA (mRNA) between colon cancer and normal tissues, as well as between groups with high and low CEACAM5 expression. Then, we constructed CEACAM5-related ceRNA networks, established the key lncRNA-miRNA-mRNA regulatory axis, and explored the biological mechanisms of this axis and its clinical significance in colon cancer from multiomic aspects. Results: We constructed a ceRNA network of 18 lncRNAs, 177 miRNAs, and 25 mRNAs associated with CEACAM5 and finally established the key LCMT1-AS2/miR-454-3p/ribosomal protein S6 kinase A5 (RPS6KA5) axis associated with overall survival. Subsequent investigations have indicated that this regulatory axis could potentially participate in the progression of COAD and exert influence on the therapeutic outcomes of chemotherapy and immunotherapy. It may be involved in the PI3K-Akt signaling pathway and may modify the tumor immune microenvironment and influence the course of COAD. Additionally, it may be related to ferroptosis, N6-methyladenosine (m6A) methylation, and tumor stemness and interfere with the sensitivity of tumor cells to 5-fluorouracil and immunotherapy. Conclusions: The LCMT1-AS2/RPS6KA5 axis may be instrumental in tumor progression, potentially acting as a prognostic biomarker and therapeutic target.

15.
Endocrine ; 2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38483687

ABSTRACT

Proteins C and S are vitamin K-dependent anticoagulative factors that also exert a significant influence on bone quality. Clinical studies have linked the deficiency of proteins C and S to lower bone mineral density and the onset of femoral head osteonecrosis in children. Rare foundational studies analyzing this topic have demonstrated that activated protein C, upon binding to the endothelial protein C receptor expressed on the surface of osteoblasts, promotes osteoblast proliferation. It is also established that proteins C and S play crucial roles in proper collagen synthesis and in maintaining the number of osteoclasts and blood vessels. However, the association between protein C and/or S deficiency and the gradual onset of osteoporosis remains largely uninvestigated. Calculations based on data from peer-reviewed journals suggest that approximately one in every 10 individuals may develop osteoporosis due to congenital protein C or S deficiency. Moreover, when secondary causes of protein C and S deficiency are also considered, the proportion likely further increases. In this paper, we discuss the pathophysiological background of the potential relationship between protein C and S deficiency and the genesis of osteoporosis.

16.
Front Immunol ; 15: 1337478, 2024.
Article in English | MEDLINE | ID: mdl-38415253

ABSTRACT

Protein S-palmitoylation is a reversible post-translational lipid modification that involves the addition of a 16-carbon palmitoyl group to a protein cysteine residue via a thioester linkage. This modification plays a crucial role in the regulation protein localization, accumulation, secretion, stability, and function. Dysregulation of protein S-palmitoylation can disrupt cellular pathways and contribute to the development of various diseases, particularly cancers. Aberrant S-palmitoylation has been extensively studied and proven to be involved in tumor initiation and growth, metastasis, and apoptosis. In addition, emerging evidence suggests that protein S-palmitoylation may also have a potential role in immune modulation. Therefore, a comprehensive understanding of the regulatory mechanisms of S-palmitoylation in tumor cells and the tumor immune microenvironment is essential to improve our understanding of this process. In this review, we summarize the recent progress of S-palmitoylation in tumors and the tumor immune microenvironment, focusing on the S-palmitoylation modification of various proteins. Furthermore, we propose new ideas for immunotherapeutic strategies through S-palmitoylation intervention.


Subject(s)
Lipoylation , Neoplasms , Humans , Protein Processing, Post-Translational , Cysteine , Tumor Microenvironment
17.
Thromb Res ; 235: 98-106, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38324941

ABSTRACT

BACKGROUND: Underlying mechanisms for bleeding and impaired thrombin generation (TG) and plasma clot formation (PCF) in patients with mild to moderate bleeding disorders (MBDs) are still to be elucidated, especially in bleeding disorder of unknown cause (BDUC). The role of the natural anticoagulants activated protein C (APC) and free protein S (PS) has not yet been investigated in this patient population. AIMS: To analyze antigen levels of APC and PS in patients with MBDs and BDUC and investigate associations to clinical bleeding phenotype and severity as well as and hemostatic capacity. METHODS: Antigen levels of APC and free PS were measured in 262 patients from the Vienna Bleeding Biobank (VIBB), a single-center cohort study, by ELISA and compared to 61 healthy controls (HC). RESULTS: Antigen levels of APC were higher in MBD patients than in HC when adjusted for age, sex and BMI (median (IQR) 33.1 (20.6-52.6) and 28.6 (16.4-47.2) ng/mL). This was most pronounced in patients with BDUC (35.3 (21.7-54.3) ng/mL). No differences in PS antigen levels between patients and HC were seen overall, or according to specific diagnoses. Further, no association between APC or PS and bleeding severity or global tests of hemostasis or TG were identified, while paradoxically APC weakly correlated with shorter lag time and time to peak of PCF in BDUC. CONCLUSION: Our data demonstrate increased antigen levels of APC in BDUC, which might contribute to the bleeding tendency in some patients and could be a future therapeutic target in BDUC.


Subject(s)
Blood Coagulation Disorders , Protein C , Humans , Cohort Studies , Anticoagulants , Enzyme-Linked Immunosorbent Assay
18.
bioRxiv ; 2024 Feb 09.
Article in English | MEDLINE | ID: mdl-38370737

ABSTRACT

Protein S (PS), the critical plasma cofactor for the anticoagulants tissue factor (TF) pathway inhibitor (TFPI) and activated protein C (APC), circulates in two functionally distinct pools: free (anticoagulant) or bound to complement component 4b-binding protein (C4BP) (anti-inflammatory). Acquired free PS deficiency is detected in several viral infections, but its cause is unclear. Here, we identified a shear-dependent interaction between PS and von Willebrand Factor (VWF) by mass spectrometry. Consistently, plasma PS and VWF comigrated in both native and agarose gel electrophoresis. The PS/VWF interaction was blocked by TFPI but not APC, suggesting an interaction with the C-terminal sex hormone binding globulin (SHBG) region of PS. Microfluidic systems, mimicking arterial laminar flow or disrupted turbulent flow, demonstrated that PS stably binds VWF as VWF unfolds under turbulent flow. PS/VWF complexes also localized to platelet thrombi under laminar arterial flow. In thrombin generation-based assays, shearing plasma decreased PS activity, an effect not seen in the absence of VWF. Finally, free PS deficiency in COVID-19 patients, measured using an antibody that binds near the C4BP binding site in SHBG, correlated with changes in VWF, but not C4BP, and with thrombin generation. Our data suggest that PS binds to a shear-exposed site on VWF, thus sequestering free PS and decreasing its anticoagulant activity, which would account for the increased thrombin generation potential. As many viral infections present with free PS deficiency, elevated circulating VWF, and increased vascular shear, we propose that the PS/VWF interaction reported here is a likely contributor to virus-associated thrombotic risk.

19.
Nitric Oxide ; 145: 21-32, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38382865

ABSTRACT

Neuronal differentiation of adipose tissue-derived stem cells (ASCs) is greatly promoted by valproic acid (VPA) with cAMP elevating agents thorough NO signaling pathways, but its mechanism is not fully understood. In the present study, we investigate the involvement of protein S-nitrosylation in the VPA-promoted neuronal differentiation of ASCs. The whole amount of S-nitrosylated protein was increased by the treatment with VPA alone for three days in ASCs. An inhibitor of thioredoxin reductase (TrxR), auranofin, further increased the amount of S-nitrosylated protein and enhances the VPA-promoted neuronal differentiation in ASCs. On the contrary, another inhibitor of TrxR, dinitrochlorobenzene, inhibited the VPA-promoted neuronal differentiation in ASCs even with cAMP elevating agents, which was accompanied by unexpectedly decreased S-nitrosylated protein. It was considered from these results that increased protein S-nitrosylation is involved in VPA-promoted neuronal differentiation of ASCs. By the proteomic analysis of S-nitrosylated protein in VPA-treated ASCs, no identified proteins could be specifically related to VPA-promoted neuronal differentiation. The identified proteins, however, included those involved in the metabolism of substances regulating neuronal differentiation, such as aspartate and glutamate.


Subject(s)
Neurons , Valproic Acid , Valproic Acid/pharmacology , Neurons/metabolism , Proteomics , Stem Cells/metabolism , Adipose Tissue
20.
Thromb J ; 22(1): 18, 2024 Feb 08.
Article in English | MEDLINE | ID: mdl-38331787

ABSTRACT

BACKGROUND:  We previously conducted a primary survey of pregnant women with hereditary thrombophilia based on national surveillance in Japan, but did not examine their thrombosis-related characteristics. Antithrombin (AT) deficiency, protein C (PC) deficiency and protein S (PS) deficiency are the major types of hereditary thrombophilia in Japan. METHODS: We examined their detailed information related to thrombosis, and evaluated peripartum outcomes in comparison with control data obtained from the Japan Society of Obstetrics and Gynecology. RESULTS: Definite or probable AT deficiency, PC deficiency and PS deficiency were observed in 80, 50, and 317 pregnancies, respectively, from 2014 to 2018 in Japan, with prevalence rates among total deliveries of 0.011%, 0.007%, 0.044%. The number of pregnancies with AT, PC and PS deficiency might have been as many as 27, 17 and 108 every year if complete answers had been provided. In the peripartum period of current pregnancies, 27.5% of women with AT deficiency, 28.0% with PC deficiency and 13.2% with PS deficiency developed thrombosis (p < 0.001 vs. control). Pregnant women with AT and PC deficiency were more susceptible to thrombosis than those with PS deficiency (P < 0.01). Of the thromboses, 92.3% occurred during pregnancy, 62.8% at less than 15 gestational weeks. The earliest onset of thrombosis was 5 gestational weeks. Prophylactic anticoagulation significantly prevented the onset of both antepartum and postpartum thrombosis (p < 0.0001). The rate of recurrent pregnancy loss in women with low PC or PS activities was significantly higher than in controls (p < 0.0001); however, it is unknown whether recurrent pregnancy loss is related to hereditary PS deficiency. There seem to have been few serious maternal or fetal/neonatal complications due to placental insufficiency related to a hypercoagulable state other than growth restriction. CONCLUSIONS: This survey revealed the thrombosis-related characteristics of pregnant women with hereditary thrombophilia in Japan. We suggest prophylactic anticoagulation to prevent maternal or fetal/neonatal complications.

SELECTION OF CITATIONS
SEARCH DETAIL
...