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1.
NPJ Microgravity ; 10(1): 51, 2024 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-38704360

RESUMEN

Human Wharton's jelly stem cells (hWJSCs) are multipotent stem cells that are extensively employed in biotechnology applications. However, the impact of simulated lunar microgravity (sµG) on the growth, differentiation, and viability of this cell population is incompletely characterized. We aimed to determine whether acute (72 h) exposure to sµG elicited changes in growth and lineage differentiation in hWJSCs and if putative changes were maintained once exposure to terrestrial gravity (1.0 G) was restored. hWJSCs were cultured under standard 1.0 G conditions prior to being passaged and cultured under sµG (0.16 G) using a random positioning machine. Relative to control, hWJSCs cultured under sµG exhibited marked reductions in growth but not viability. Cell population expression of characteristic stemness markers (CD 73, 90, 105) was significantly reduced under sµG conditions. hWJSCs had 308 significantly upregulated and 328 significantly downregulated genes when compared to 1.0 G culture conditions. Key markers of cell replication, including MKI67, were inhibited. Significant upregulation of osteocyte-chondrocyte lineage markers, including SERPINI1, MSX2, TFPI2, BMP6, COMP, TMEM119, LUM, HGF, CHI3L1 and SPP1, and downregulation of cell fate regulators, including DNMT1 and EZH2, were detected in sµG-exposed hWJSCs. When returned to 1.0 G for 3 days, sµG-exposed hWJSCs had accelerated growth, and expression of stemness markers increased, approaching normal (i.e. 95%) levels. Our data support earlier findings that acute sµG significantly reduces the cell division potential of hWJSCs and suggest that acute sµG-exposure induces reversible changes in cell growth accompanied by osteocyte-chondrocyte changes in lineage differentiation.

2.
Mol Metab ; : 101956, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38735390

RESUMEN

OBJECTIVE: Sulfonylureas (SUs) are still among the mostly prescribed antidiabetic drugs with an established mode of action: release of insulin from pancreatic ß-cells. In addition, effects of SUs on adipocytes by activation of the nuclear receptor peroxisome proliferator-activated receptor γ (PPARγ) have been described, which might explain their insulin-sensitizing potential observed in patients. However, there is a discrepancy between the impact of SUs on antidiabetic action and their rather moderate in vitro effect on PPARγ transcriptional activity. Recent studies have shown that some PPARγ ligands can improve insulin sensitivity by blocking PPARγ Ser-273 phosphorylation without having full agonist activity. It is unknown if SUs elicit their antidiabetic effects on adipocytes by inhibition of PPARγ phosphorylation. Here, we investigated if binding of SUs to PPARγ can interfere with PPARγ Ser-273 phosphorylation and determined their antidiabetic actions in vitro in primary human white adipocytes and in vivo in high-fat diet (HFD) obese mice. METHODS: Primary human white preadipocytes were differentiated in the presence of glibenclamide, glimepiride and PPARγ ligands rosiglitazone and SR1664 to compare PPARγ Ser-273 phosphorylation, glucose uptake and adipokine expression. Transcriptional activity at PPARγ was determined by luciferase assays, quantification of PPARγ Ser-273 phosphorylation was determined by Western blotting and CDK5 kinase assays. In silico modelling was performed to gain insight into the binding characteristics of SUs to PPARγ. HFD mice were administered SUs and rosiglitazone for 6 days. PPARγ Ser-273 phosphorylation in white adipose tissue (WAT), body composition, glucose tolerance, adipocyte morphology and expression levels of genes involved in PPARγ activity in WAT and brown adipose tissue (BAT) were evaluated. RESULTS: SUs inhibit phosphorylation of PPARγ at Ser-273 in primary human white adipocytes and exhibit a positive antidiabetic expression profile, which is characterized by up regulation of insulin-sensitizing and down regulation of insulin resistance-inducing adipokines. We demonstrate that SUs directly bind to PPARγ by in silico modelling and inhibit phosphorylation in kinase assays to a similar extend as rosiglitazone and SR1664. In HFD mice SUs reduce PPARγ phosphorylation in WAT and have comparable effects on gene expression to rosiglitazone. In BAT SUs increase UCP1 expression and reduce lipid droplets sizes. CONCLUSIONS: Our findings indicate that a part of SUs extra-pancreatic effects on adipocytes in vitro and in vivo is probably mediated via their interference with PPARγ phosphorylation rather than via classical agonistic activity at clinical concentrations.

3.
Thromb Res ; 237: 184-195, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38631156

RESUMEN

BACKGROUND AND AIMS: Blood disorders, such as sickle cell disease, and other clinical conditions are often accompanied by intravascular hemolytic events along with the development of severe coagulopathies. Hemolysis, in turn, leads to the accumulation of Fe(II/III)-protoporphyrin IX (heme) in the intravascular compartment, which can trigger a variety of proinflammatory and prothrombotic reactions. As such, heme binding to the blood coagulation proteins factor VIII (FVIII), fibrinogen, and activated protein C with functional consequences has been demonstrated earlier. METHODS: We herein present an in-depth characterization of the FVIII-heme interaction at the molecular level and its (patho-)physiological relevance through the application of biochemical, biophysical, structural biology, bioinformatic, and diagnostic tools. RESULTS: FVIII has a great heme-binding capacity with seven heme molecules associating with the protein. The respective binding sites were identified by investigating heme binding to FVIII-derived peptides in combination with molecular docking and dynamic simulation studies of the complex as well as cryo-electron microscopy, revealing three high-affinity and four moderate heme-binding motifs (HBMs). Furthermore, the relevance of the FVIII-heme complex formation was characterized in physiologically relevant assay systems, revealing a ~ 50 % inhibition of the FVIII cofactor activity even in the protein-rich environment of blood plasma. CONCLUSION: Our study provides not only novel molecular insights into the FVIII-heme interaction and its physiological relevance, but also strongly suggests the reduction of the intrinsic pathway and the accentuation of the final clotting step (by, for example, fibrinogen crosslinking) in hemolytic conditions as well as a future perspective in the context of FVIII substitution therapy of hemorrhagic events in hemophilia A patients.


Asunto(s)
Factor VIII , Hemo , Humanos , Sitios de Unión , Coagulación Sanguínea , Factor VIII/metabolismo , Factor VIII/química , Hemo/metabolismo , Simulación del Acoplamiento Molecular , Unión Proteica , Relación Estructura-Actividad
4.
J Thromb Haemost ; 22(2): 379-393, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37832789

RESUMEN

BACKGROUND: The characterization of inherited mild factor XIII deficiency is more imprecise than its rare, inherited severe forms. It is known that heterozygosity at FXIII genetic loci results in mild FXIII deficiency, characterized by circulating FXIII activity levels ranging from 20% to 60%. There exists a gap in information on 1) how genetic heterozygosity renders clinical bleeding manifestations among these individuals and 2) the reversal of unexplained bleeding upon FXIII administration in mild FXIII-deficient individuals. OBJECTIVES: To assess the prevalence and burden of mild FXIII deficiency among the apparently healthy German-Caucasian population and correlate it with genetic heterozygosity at FXIII and fibrinogen gene loci. METHODS: Peripheral blood was collected from 752 donors selected from the general population with essentially no bleeding complications to ensure asymptomatic predisposition. These were assessed for FXIII and fibrinogen activity, and FXIII and fibrinogen genes were resequenced using next-generation sequencing. For comparison, a retrospective analysis was performed on a cohort of mild inherited FXIII deficiency patients referred to us. RESULTS: The prevalence of mild FXIII deficiency was high (∼0.8%) among the screened German-Caucasian population compared with its rare-severe forms. Although no new heterozygous missense variants were found, certain combinations were relatively dominant/prevalent among the mild FXIII-deficient individuals. CONCLUSION: This extensive, population-based quasi-experimental approach revealed that the burden of heterozygosity in FXIII and fibrinogen gene loci causes the clinical manifestation of inherited mild FXIII deficiency, resulting in ''unexplained bleeding'' upon provocation.


Asunto(s)
Deficiencia del Factor XIII , Factor XIII , Hemostáticos , Humanos , Factor XIII/genética , Deficiencia del Factor XIII/diagnóstico , Deficiencia del Factor XIII/genética , Fibrinógeno/genética , Hemorragia/diagnóstico , Hemorragia/genética , Estudios Retrospectivos
5.
Haemophilia ; 29(6): 1483-1489, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37707428

RESUMEN

INTRODUCTION AND AIM: Severe haemophilia B (HB) is characterized by spontaneous bleeding episodes, mostly into joints. Recurrent bleeds lead to progressive joint destruction called haemophilic arthropathy. The current concept of prophylaxis aims at maintaining the FIX level >3-5 IU/dL, which is effective at reducing the incidence of haemophilic arthropathy. Extended half-life FIX molecules make it easier to achieve these target trough levels compared to standard FIX concentrates. We previously reported that the fusion of a recombinant FIX (rFIX) to factor XIII-B (FXIIIB) subunit prolonged the half-life of the rFIX-LXa-FXIIIB fusion molecule in mice and rats 3.9- and 2.2-fold, respectively, compared with rFIX-WT. However, the mechanism behind the extended half-life was not known. MATERIALS AND METHODS: Mass spectrometry and ITC were used to study interactions of rFIX-LXa-FXIIIB with albumin. Pharmacokinetic analyses in fibrinogen-KO and FcRn-KO mice were performed to evaluate the effect of albumin and fibrinogen on in-vivo half-life of rFIX-LXa-FXIIIB. Finally saphenous vein bleeding model was used to assess in-vivo haemostatic activity of rFIX-LXa-FXIIIB. RESULTS AND CONCLUSION: We report here the key interactions that rFIX-LXa-FXIIIB may have in plasma are with fibrinogen and albumin which may mediate its prolonged half-life. In addition, using the saphenous vein bleeding model, we demonstrate that rFIX-FXIIIB elicits functional clot formation that is indistinguishable from that of rFIX-WT.


Asunto(s)
Hemofilia B , Hemostáticos , Artropatías , Enfermedades Vasculares , Ratones , Ratas , Animales , Factor IX/genética , Factor IX/farmacología , Factor IX/uso terapéutico , Factor XIII/farmacología , Factor XIII/uso terapéutico , Proteínas Recombinantes de Fusión/uso terapéutico , Proteínas Recombinantes de Fusión/farmacocinética , Hemofilia B/tratamiento farmacológico , Hemorragia/prevención & control , Hemostáticos/uso terapéutico , Albúminas , Fibrinógeno/uso terapéutico , Semivida , Artropatías/tratamiento farmacológico , Proteínas Recombinantes/farmacología , Proteínas Recombinantes/uso terapéutico , Proteínas Recombinantes/química
7.
ACS Nano ; 17(14): 13594-13610, 2023 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-37458484

RESUMEN

Delivery of mRNA-based therapeutics to the perinatal brain holds great potential in treating congenital brain diseases. However, nonviral delivery platforms that facilitate nucleic acid delivery in this environment have yet to be rigorously studied. Here, we screen a diverse library of ionizable lipid nanoparticles (LNPs) via intracerebroventricular (ICV) injection in both fetal and neonatal mice and identify an LNP formulation with greater functional mRNA delivery in the perinatal brain than an FDA-approved industry standard LNP. Following in vitro optimization of the top-performing LNP (C3 LNP) for codelivery of an adenine base editing platform, we improve the biochemical phenotype of a lysosomal storage disease in the neonatal mouse brain, exhibit proof-of-principle mRNA brain transfection in vivo in a fetal nonhuman primate model, and demonstrate the translational potential of C3 LNPs ex vivo in human patient-derived brain tissues. These LNPs may provide a clinically translatable platform for in utero and postnatal mRNA therapies including gene editing in the brain.


Asunto(s)
Encefalopatías , Nanopartículas , Ratones , Humanos , Animales , Edición Génica , Lípidos , Liposomas , ARN Mensajero/genética , ARN Interferente Pequeño/genética
8.
J Clin Med ; 12(3)2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36769414

RESUMEN

Advanced mitochondrial multi-omics indicate a multi-facet involvement of mitochondria in the physiology of the cell, changing the perception of mitochondria from being just the energy-generating organelles to organelles that highly influence cell structure, function, signaling, and cell fate. This sets mitochondrial dysfunction in the centerstage of numerous acquired and genetic diseases. Sickle cell disease is also being increasingly associated with mitochondrial anomalies and the pathophysiology of sickle cell disease finds mitochondria at crucial intersections in the pathological cascade. Altered mitophagy, increased ROS, and mitochondrial DNA all contribute to the condition and its severity. Such mitochondrial aberrations lead to consequent mitochondrial retention in red blood cells in sickle cell diseases, increased oxidation in the cellular environment, inflammation, worsened vaso-occlusive crisis, etc. There are increasing studies indicating mitochondrial significance in sickle cell disease, consequently providing an opportunity to target it for improving the outcomes of treatment. Identification of the impaired mitochondrial attributes in sickle cell disease and their modulation by therapeutic interventions can impart a better management of the disease. This review aims to describe the mitochondria in the perspective of sicke cell disease so as to provide the reader an overview of the emerging mitochondrial stance in sickle cell disease.

10.
Blood Rev ; 59: 101032, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36372609

RESUMEN

Coagulation factor XIII (FXIII) acts as a fine fulcrum in blood plasma that maintains the balance between bleeding and thrombosis by covalently crosslinking the pre-formed fibrin clot into an insoluble one that is resistant to premature fibrinolysis. In plasma, FXIII circulates as a pro-transglutaminase complex composed of the dimeric catalytic FXIII-A encoded by the F13A1 gene and dimeric carrier/regulatory FXIII-B subunits encoded by the F13B gene. Growing evidence accumulated over decades of exhaustive research shows that not only does FXIII play major roles in both pathological extremes of hemostasis i.e. bleeding and thrombosis, but that it is, in fact, a pleiotropic protein with physiological roles beyond coagulation. However, the current FXIII genetic-epidemiological literature is overwhelmingly derived from the bleeding pathology associated with its deficiency. In this article we review the current clinical, functional, and molecular understanding of this fascinating multifaceted protein, especially putting into the same perspective its genetic landscape.


Asunto(s)
Factor XIII , Trombosis , Humanos , Factor XIII/genética , Factor XIII/metabolismo , Coagulación Sanguínea , Fibrina
11.
Genes (Basel) ; 13(12)2022 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-36553524

RESUMEN

The current gold standard for the definitive diagnosis of fetal aneuploidy uses either chorionic villus sampling (CVS) or amniocentesis, both of which are which are invasive procedures carrying a procedure-related risk of miscarriage of up to 0.1-0.2%. Non-invasive prenatal diagnosis using fetal nucleated red blood cells (FNRBCs) isolated from maternal peripheral venous blood would remove this risk of miscarriage since these cells can be isolated from the mother's blood. We aimed to detect whole-chromosome aneuploidies from single nucleated fetal red blood cells using whole-genome amplification followed by massively parallel sequencing performed on a semiconductor sequencing platform. Twenty-six single cells were picked from the placental villi of twelve patients thought to have a normal fetal genotype and who were undergoing elective first-trimester surgical termination of pregnancy. Following karyotyping, it was subsequently found that two of these cases were also abnormal (one trisomy 15 and one mosaic genotype). One single cell from chorionic villus samples for two patients carrying a fetus with trisomy 21 and two single cells from women carrying fetuses with T18 were also picked. Pooled libraries were sequenced on the Ion Proton and data were analysed using Ion Reporter software. We correctly classified fetal genotype in all 24 normal cells, as well as the 2 T21 cells, the 2 T18 cells, and the two T15 cells. The two cells picked from the fetus with a mosaic result by CVS were classified as unaffected, suggesting that this was a case of confined placental mosaicism. Fetal sex was correctly assigned in all cases. We demonstrated that semiconductor sequencing using commercially available software for data analysis can be achieved for the non-invasive prenatal diagnosis of whole-chromosome aneuploidy with 100% accuracy.


Asunto(s)
Aborto Espontáneo , Enfermedades Fetales , Embarazo , Humanos , Femenino , Diagnóstico Prenatal/métodos , Aborto Espontáneo/diagnóstico , Aborto Espontáneo/genética , Placenta , Aneuploidia , Enfermedades Fetales/genética , Cariotipificación , Mosaicismo , Eritrocitos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Cromosomas
12.
Singapore Med J ; 63(5): 274-282, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-36043312

RESUMEN

INTRODUCTION: Selective fetoscopic laser photocoagulation (SFLP) for twin-to-twin transfusion syndrome (TTTS) is challenging for new surgeons at the start of their learning curve. We described an approach utilising telementoring and team-based training to facilitate rapid attainment of the skills required for safe and efficient practice with a limited caseload. METHODS: We conducted a prospective observational study of SFLP performed by the novice primary surgical team in three stages: under direct on-site supervision from an expert mentor (Group 1), with remote tele-guidance from that mentor (Group 2) and independently (Group 3), at an academic tertiary hospital in Singapore. The primary team undertook regular training on high-fidelity tissue models to accelerate skills acquisition and complement the surgical performance. RESULTS: 9 patients diagnosed with Stage 2 TTTS were assessed for procedural characteristics, surgical outcomes and perinatal survival following SFLP. There were no significant differences in operative duration, anastomoses ablated, gestational age or birth weight at delivery. The complications observed were: recurrent TTTS (22.2% of pregnancies), twin anaemia polycythaemia sequence (33.3%), preterm prelabour membrane rupture (22.2%) and delivery at < 32 weeks (44.4%). ≥ 1 twin was live-born in 88.9% of cases, while postnatal survival to six months of ≥ 1 twin occurred in 77.8% of cases. CONCLUSION: Systematic mentoring and specialised skills training are useful in aiding new surgeons to negotiate the steep learning curve and achieve good outcomes at the start of a new practice, particularly in the setting of low patient numbers. This is best paired with dedicated model training to achieve and maintain surgical dexterity for this complex procedure.


Asunto(s)
Transfusión Feto-Fetal , Tutoría , Femenino , Transfusión Feto-Fetal/cirugía , Fetoscopía/métodos , Edad Gestacional , Humanos , Recién Nacido , Coagulación con Láser/métodos , Rayos Láser , Curva de Aprendizaje , Mentores , Embarazo , Embarazo Gemelar
13.
Int J Mol Sci ; 23(9)2022 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-35563115

RESUMEN

Coagulation factor XIII (FXIII) circulates in plasma as a pro-transglutaminase heterotetrameric complex (FXIIIA2B2), which upon activation by thrombin and calcium covalently crosslinks preformed fibrin polymers. The heterotetrameric complex is composed of a catalytic FXIIIA2 subunit and a protective/regulatory FXIII-B2 subunit coded by F13A1 and F13B genes, respectively. The catalytic FXIIIA2 subunit is encoded by the F13A1 gene, expressed primarily in cells of mesenchymal origin, whereas the FXIIIB subunit encoded by the F13B gene is expressed and secreted from hepatocytes. The plasma FXIIIA2 subunit, which earlier was believed to be secreted from cells of megakaryocytic lineage, is now understood to result primarily from resident macrophages. The regulation of the FXIII subunits at the genetic level is still poorly understood. The current study adopts a purely bioinformatic approach to analyze the temporal, time-specific expression array-data corresponding to both the subunits in specific cell lineages, with respect to the gene promoters. We analyze the differentially expressed genes correlated with F13A1 and F13B expression levels in an array of cell types, utilizing publicly available microarray data. We attempt to understand the regulatory mechanism underlying the variable expression of FXIIIA2 subunit in macrophages (M0, M1, M2 and aortic resident macrophages). Similarly, the FXIIIB2 subunit expression data from adult, fetal hepatocytes and embryonic stem cells derived hepatoblasts (hESC-hepatoblast) was analyzed. The results suggest regulatory dependence between the two FXIII subunits at the transcript level. Our analysis also predicts the involvement of the FXIIIA2 subunit in macrophage polarization, plaque stability, and inflammation.


Asunto(s)
Biología Computacional , Factor XIII , Pruebas de Coagulación Sanguínea , Factor XIII/genética , Factor XIII/metabolismo , Fibrina , Trombina/metabolismo
14.
Clin Lab ; 68(3)2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35254039

RESUMEN

BACKGROUND: Deep Vein Thrombosis (DVT) is a multicausal disease involving both acquired as well as genetic factors. Nitric oxide is an influential endogenous factor having its role in the development of deep vein thrombosis. It maintains the vascular integrity and any alterations in its levels may lead to a thrombotic event. It may also modulate homocysteine metabolism to cause hyperhomocysteinemia, which is a prominent risk factor for thrombosis. The objective of the study was to study if endothelial nitric oxide gene polymorphisms, 894G/T, and 2479G/A alter the plasma nitric oxide and homocysteine levels which may eventually increase the risk of deep vein thrombosis. METHODS: One hundred Doppler ultrasonography and computerized tomography confirmed (for cerebral venous thrombosis), non-related DVT patients (M:F = 58:42; age range = 18 to 61 years) served as the study population. Two hundred hospital staff and their relatives or unrelated attendants of the patients served as the controls. Nitric oxide levels were determined by measuring its metabolites (NOx), and EIA was used to measure homocysteine levels. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used for detecting the eNOS polymorphisms 894G/T and 2479G/A. RESULTS: In total, DVT subjects have 25% higher plasma levels of homocysteine and 37% lower levels of NOx in their circulation when compared to controls. In tertile analysis of nitric oxide and homocysteine levels, 894G/T and 2479G/A polymorphisms were associated with plasma nitric oxide and homocysteine levels. The increased risk of deep vein thrombosis was associated with endothelial nitric oxide gene polymorphisms and nitric oxide levels, but homocysteine levels were not a risk for deep vein thrombosis. CONCLUSION: The present study demonstrates that 894G/T and 2479G/A polymorphisms interact with lower levels of nitric oxide and higher levels of homocysteine that may possess the risk of deep vein thrombosis.


Asunto(s)
Óxido Nítrico Sintasa de Tipo III , Trombosis de la Vena , Adolescente , Adulto , Genotipo , Homocisteína , Humanos , Persona de Mediana Edad , Óxido Nítrico , Óxido Nítrico Sintasa de Tipo III/genética , Polimorfismo Genético , Trombosis de la Vena/genética , Adulto Joven
15.
Sci Rep ; 12(1): 3907, 2022 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-35273269

RESUMEN

The objective of the study is to investigate the effect of Nuchal Fold (NF) in predicting Fetal Growth Restriction (FGR) using machine learning (ML), to explain the model's results using model-agnostic interpretable techniques, and to compare the results with clinical guidelines. This study used second-trimester ultrasound biometry and Doppler velocimetry were used to construct six FGR (birthweight < 3rd centile) ML models. Interpretability analysis was conducted using Accumulated Local Effects (ALE) and Shapley Additive Explanations (SHAP). The results were compared with clinical guidelines based on the most optimal model. Support Vector Machine (SVM) exhibited the most consistent performance in FGR prediction. SHAP showed that the top contributors to identify FGR were Abdominal Circumference (AC), NF, Uterine RI (Ut RI), and Uterine PI (Ut PI). ALE showed that the cutoff values of Ut RI, Ut PI, and AC in differentiating FGR from normal were comparable with clinical guidelines (Errors between model and clinical; Ut RI: 15%, Ut PI: 8%, and AC: 11%). The cutoff value for NF to differentiate between healthy and FGR is 5.4 mm, where low NF may indicate FGR. The SVM model is the most stable in FGR prediction. ALE can be a potential tool to identify a cutoff value for novel parameters to differentiate between healthy and FGR.


Asunto(s)
Retardo del Crecimiento Fetal , Medida de Translucencia Nucal , Femenino , Retardo del Crecimiento Fetal/diagnóstico por imagen , Humanos , Aprendizaje Automático , Embarazo , Segundo Trimestre del Embarazo , Ultrasonografía Prenatal/métodos
16.
Hum Mutat ; 43(1): 42-55, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34816548

RESUMEN

γ-Glutamyl carboxylase (GGCX) catalyzes the γ-carboxylation of 15 different vitamin K dependent (VKD) proteins. Pathogenic variants in GGCX cause a rare hereditary bleeding disorder called Vitamin K dependent coagulation factor deficiency type 1 (VKCFD1). In addition to bleedings, some VKCFD1 patients develop skin laxity and skeletal dysmorphologies. However, the pathophysiological mechanisms underlying these non-hemorrhagic phenotypes remain elusive. Therefore, we have analyzed 20 pathogenic GGCX variants on their ability to γ-carboxylate six non-hemostatic VKD proteins in an in vitro assay, where GGCX variants were expressed in GGCX-/- cells and levels of γ-carboxylated co-expressed VKD proteins were detected by a functional ELISA. We observed that GGCX variants causing markedly reduced γ-carboxylation of Gla rich protein (GRP) in vitro were reported in patients with skin laxity. Reduced levels of γ-carboxylated Matrix gla protein (MGP) are not exclusive for causing skeletal dysmorphologies in VKCFD1 patients. In silico docking of vitamin K hydroquinone on a GGCX model revealed a binding site, which was validated by in vitro assays. GGCX variants affecting this site result in disability to γ-carboxylate VKD proteins and hence are involved in the most severe phenotypes. This genotype-phenotype analysis will help to understand the development of non-hemorrhagic phenotypes and hence improve treatment in VKCFD1 patients.


Asunto(s)
Trastornos de la Coagulación Sanguínea Heredados , Ligasas de Carbono-Carbono , Trastornos de la Coagulación Sanguínea Heredados/genética , Ligasas de Carbono-Carbono/química , Ligasas de Carbono-Carbono/genética , Ligasas de Carbono-Carbono/metabolismo , Carboxiliasas , Humanos , Mutación
17.
Cancers (Basel) ; 13(16)2021 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-34439147

RESUMEN

BACKGROUND: PPARγ (peroxisome proliferator-activated receptor gamma) is involved in the pathology of numerous diseases, including UM and other types of cancer. Emerging evidence suggests that an interaction between PPARγ and DNMTs (DNA methyltransferase) plays a role in cancer that is yet to be defined. METHODS: The configuration of the repeating elements was performed with CAP3 and MAFFT, and the structural modelling was conducted with HDOCK. An evolutionary action scores algorithm was used to identify oncogenic variants. A systematic bioinformatic appraisal of PPARγ and DNMT1 was performed across 29 tumor types and UM available in The Cancer Genome Atlas (TCGA). RESULTS: PPAR-responsive elements (PPREs) enriched with Alu repeats are associated with different genomic regions, particularly the promotor region of DNMT1. PPARγ-DNMT1 co-expression is significantly associated with several cancers. C-terminals of PPARγ and DNMT1 appear to be the potential protein-protein interaction sites where disease-specific mutations may directly impair the respective protein functions. Furthermore, PPARγ expression could be identified as an additional prognostic marker for UM. CONCLUSIONS: We hypothesize that the function of PPARγ requires an additional contribution of Alu repeats which may directly influence the DNMT1 network. Regarding UM, PPARγ appears to be an additional discriminatory prognostic marker, in particular in disomy 3 tumors.

18.
Diabetes Res Clin Pract ; 178: 108978, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34303772

RESUMEN

AIMS: To explore the glucose-overload hypothesis of artefactual gestational diabetes (GDM) diagnosis in shorter women during oral glucose tolerance testing (OGTT), by investigating associations between height and maternal glycemia; and GDM and pregnancy complications in height-groups. METHODS: Women from GUSTO (n = 1100, 2009-2010) and NUH (n = 4068, 2017-2018) cohorts underwent a mid-gestation two and three time-point 75 g 2-hour OGTT, respectively. GDM-related complications (hypertensive disorders of pregnancy, preterm delivery, emergency cesarean section, neonatal intensive care unit admission, macrosomia, birthweight) were compared within shorter and taller groups, dichotomized by ethnic-specific median height. RESULTS: Using WHO-1999 criteria, 18.8% (GUSTO) to 22.9% (NUH) of women were diagnosed with GDM-1999; and by WHO-2013 criteria, 21.9% (NUH) had GDM-2013. Each 5-cm height increment was inversely associated with GDM-1999 (adjusted odds ratio [aOR, 95% CI] = 0.81 [0.76-0.87], 2-h glycemia (adjusted ß [aß, 95% CI] = -0.171 mmol/L [-0.208, -0.135]) and 1-h glycemia (aß = -0.160 mmol/L [-0.207, -0.112]). The inverse association between height and 2-h glycemia was most marked in "Other" ethnicities (Eurasians/Caucasians/mixed/other Asians) and Indians, followed by Chinese, then Malays. Compared with non-GDM, GDM-1999 was associated with preterm delivery (aOR = 1.76 [1.19-2.61]) and higher birthweight (aß = 57.16 g [20.95, 93.38]) only among taller but not shorter women. CONCLUSIONS: Only taller women had an increased odds of GDM-related pregnancy complications. An artefactual GDM diagnosis due to glucose-overload among shorter women is plausible.


Asunto(s)
Diabetes Gestacional , Complicaciones del Embarazo , Glucemia , Cesárea , Diabetes Gestacional/epidemiología , Femenino , Macrosomía Fetal/epidemiología , Macrosomía Fetal/etiología , Prueba de Tolerancia a la Glucosa , Humanos , Recién Nacido , Embarazo , Resultado del Embarazo/epidemiología
19.
J Clin Med ; 10(9)2021 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-34065057

RESUMEN

Coronavirus disease 2019 (COVID-19), with a broad range of clinical and laboratory findings, is currently the most prevalent medical challenge worldwide. In this disease, hypercoagulability and hyperinflammation, two common features, are accompanied by a higher rate of morbidity and mortality. We assessed the association between baseline inflammatory cytokine levels and coagulopathy and disease outcome in COVID-19. One hundred and thirty-seven consecutive patients hospitalized with COVID-19 were selected for the study. Baseline interleukin-1 (IL-1), IL-6, and tumor necrosis factor alpha (TNF-α) level were measured at time of admission. At the same time, baseline coagulation parameters were also assessed during the patient's hospitalization. Clinical findings, including development of thrombosis and clinical outcome, were recorded prospectively. Out of 136 patients, 87 (~64%) had increased cytokine levels (one or more cytokines) or abnormal coagulation parameters. Among them, 58 (~67%) had only increased inflammatory cytokines, 12 (~14%) had only coagulation abnormalities, and 17 (19.5%) had concomitant abnormalities in both systems. It seems that a high level of inflammatory cytokines at admission points to an increased risk of developing coagulopathy, thrombotic events, even death, over the course of COVID-19. Early measurement of these cytokines, and timely co-administration of anti-inflammatories with anticoagulants could decrease thrombotic events and related fatal consequences.

20.
Prenat Diagn ; 41(8): 1018-1035, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34191294

RESUMEN

There are over 50 SARS-CoV-2 candidate vaccines undergoing Phase II and III clinical trials. Several vaccines have been approved by regulatory authorities and rolled out for use in different countries. Due to concerns of potential teratogenicity or adverse effect on maternal physiology, pregnancy has been a specific exclusion criterion for most vaccine trials with only two trials not excluding pregnant women. Thus, other than limited animal studies, gradually emerging development and reproductive toxicity data, and observational data from vaccine registries, there is a paucity of reliable information to guide recommendations for the safe vaccination of pregnant women. Pregnancy is a risk factor for severe COVID-19, especially in women with comorbidities, resulting in increased rates of preterm birth and maternal morbidity. We discuss the major SARS-CoV-2 vaccines, their mechanisms of action, efficacy, safety profile and possible benefits to the maternal-fetal dyad to create a rational approach towards maternal vaccination while anticipating and mitigating vaccine-related complications. Pregnant women with high exposure risks or co-morbidities predisposing to severe COVID-19 infection should be prioritised for vaccination. Those with risk factors for adverse effects should be counselled accordingly. It is essential to support patient autonomy by shared decision-making involving a risk-benefit discussion with the pregnant woman.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19/prevención & control , Complicaciones Infecciosas del Embarazo/prevención & control , SARS-CoV-2/inmunología , COVID-19/inmunología , Femenino , Humanos , Embarazo , Complicaciones Infecciosas del Embarazo/inmunología , Vacunación/ética
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