COVID-19 and individual genetic susceptibility/receptivity: Role of ACE1/ACE2 genes, immunity, inflammation and coagulation. might the double x-chromosome in females be protective against SARS-COV-2 compared to the single x-chromosome in males?

In December 2019, a novel severe acute respiratory syndrome (SARS) from a new coronavirus (SARS-CoV-2) was recognized in the city of Wuhan, China. Rapidly, it became an epidemic in China and has now spread throughout the world reaching pandemic proportions. High mortality rates characterize SARS-CoV-2 disease (COVID-19), which mainly affects the elderly, causing unrestrained cytokines-storm and subsequent pulmonary shutdown, also suspected micro thromboembolism events. At the present time, no specific and dedicated treatments, nor approved vaccines, are available, though very promising data come from the use of anti-inflammatory, anti-malaria, and anti-coagulant drugs. In addition, it seems that males are more susceptible to SARS-CoV-2 than females, with males 65% more likely to die from the infection than females. Data from the World Health Organization (WHO) and Chinese scientists show that of all cases about 1.7% of women who contract the virus will die compared with 2.8% of men, and data from Hong Kong hospitals state that 32% of male and 15% of female COVID-19 patients required intensive care or died. On the other hand, the long-term fallout of coronavirus may be worse for women than for men due to social and psychosocial reasons. Regardless of sex-or gender-biased data obtained from WHO and those gathered from sometimes controversial scientific journals, some central points should be considered. Firstly, SARS-CoV-2 has a strong interaction with the human ACE2 receptor, which plays an essential role in cell entry together with transmembrane serine protease 2 (TMPRSS2); it is interesting to note that the ACE2 gene lays on the X-chromosome, thus allowing females to be potentially heterozygous and differently assorted compared to men who are definitely hemizygous. Secondly, the higher ACE2 expression rate in females, though controversial, might ascribe them the worst prognosis, in contrast with worldwide epidemiological data. Finally, several genes involved in inflammation are located on the X-chromosome, which also contains high number of immune-related genes responsible for innate and adaptive immune responses to infection. Other genes, out from the RAS-pathway, might directly or indirectly impact on the ACE1/ACE2 balance by influencing its main actors (e.g., ABO locus, SRY, SOX3, ADAM17). Unexpectedly, the higher levels of ACE2 or ACE1/ACE2 rebalancing might improve the outcome of COVID-19 in both sexes by reducing inflammation, thrombosis, and death. Moreover, X-heterozygous females might also activate a mosaic advantage and show more pronounced sex-related differences resulting in a sex dimorphism, further favoring them in counteracting the progression of the SARS-CoV-2 infection

Revisiting the mechanism of coagulation factor XIII activation and regulation from a structure/functional perspective

The activation and regulation of coagulation Factor XIII (FXIII) protein has been the subject of active research for the past three decades. Although discrete evidence exists on various aspects of FXIII activation and regulation a combinatorial structure/functional view in this regard is lacking. In this study, we present results of a structure/function study of the functional chain of events for FXIII. Our study shows how subtle chronological submolecular changes within calcium binding sites can bring about the detailed transformation of the zymogenic FXIII to its activated form especially in the context of FXIIIA and FXIIIB subunit interactions. We demonstrate what aspects of FXIII are important for the stabilization (first calcium binding site) of its zymogenic form and the possible modes of deactivation (thrombin mediated secondary cleavage) of the activated form. Our study for the first time provides a structural outlook of the FXIIIA 2 B 2 heterotetramer assembly, its association and dissociation. The FXIIIB subunits regulatory role in the overall process has also been elaborated upon. In summary, this study provides detailed structural insight into the mechanisms of FXIII activation and regulation that can be used as a template for the development of future highly specific therapeutic inhibitors targeting FXIII in pathological conditions like thrombosis

TRAIL, OPG, and TWEAK in kidney disease: biomarkers or therapeutic targets?

Ligands and receptors of the tumor necrosis factor (TNF) superfamily regulate immune responses and homeostatic functions with potential diagnostic and therapeutic implications. Kidney disease represents a global public health problem, whose prevalence is rising worldwide, due to the aging of the population and the increasing prevalence of diabetes, hypertension, obesity, and immune disorders. In addition, chronic kidney disease is an independent risk factor for the development of cardiovascular disease, which further increases kidney-related morbidity and mortality. Recently, it has been shown that some TNF superfamily members are actively implicated in renal pathophysiology. These members include TNF-related apoptosis-inducing ligand (TRAIL), its decoy receptor osteoprotegerin (OPG), and TNF-like weaker inducer of apoptosis (TWEAK). All of them have shown the ability to activate crucial pathways involved in kidney disease development and progression (e.g. canonical and non-canonical pathways of the transcription factor nuclear factor-kappa B), as well as the ability to regulate cell proliferation, differentiation, apoptosis, necrosis, inflammation, angiogenesis, and fibrosis with double-edged effects depending on the type and stage of kidney injury. Here we will review the actions of TRAIL, OPG, and TWEAK on diabetic and non-diabetic kidney disease, in order to provide insights into their full clinical potential as biomarkers and/or therapeutic options against kidney disease

Polymorphisms in the genes coding for iron binding and transporting proteins are associated with disability, severity, and early progression in multiple sclerosis

ABSTRACT: BACKGROUND: Iron involvement/imbalance is strongly suspected in multiple sclerosis (MS) etiopathogenesis, but its role is quite debated. Iron deposits encircle the veins in brain MS lesions, increasing local metal concentrations in brain parenchyma as documented by magnetic resonance imaging and histochemical studies. Conversely, systemic iron overload is not always observed. We explored the role of common single nucleotide polymorphisms (SNPs) in the main iron homeostasis genes in MS patients. METHODS: By the pyrosequencing technique, we investigated 414 MS cases [Relapsing-remitting (RR), n=273; Progressive, n=141, of which: Secondary (SP), n=103 and Primary (PP), n=38], and 414 matched healthy controls. Five SNPs in 4 genes were assessed: hemochromatosis (HFE: C282Y, H63D), ferroportin (FPN1: -8CG), hepcidin (HEPC: -582AG), and transferrin (TF: P570S). RESULTS: The FPN1-8GG genotype was overrepresented in the whole MS population (OR=4.38; 95%CI, 1.89-10.1; P<0.0001) and a similar risk was found among patients with progressive forms. Conversely, the HEPC -582GG genotype was overrepresented only in progressive forms (OR=2.53; 95%CI, 1.34-4.78; P=0.006) so that SP and PP versus RR yielded significant outputs (P=0.009). For almost all SNPs, MS disability score (EDSS), severity score (MSSS), as well as progression index (PI) showed a significant increase when comparing homozygotes versus individuals carrying other genotypes: HEPC -582GG (EDSS, 4.24+/-2.87 vs 2.78+/-2.1; P=0.003; MSSS, 5.6+/-3.06 vs 3.79+/-2.6; P=0.001); FPN1-8GG (PI, 1.11+/-2.01 vs 0.6+/-1.31; P=0.01; MSSS, 5.08+/-2.98 vs 3.85+/-2.8; P=0.01); HFE 63DD (PI, 1.63+/-2.6 vs 0.6+/-0.86; P=0.009). Finally, HEPC -582G-carriers had a significantly higher chance to switch into the progressive form (HR=3.55; 1.83-6.84; log-rank P=0.00006). CONCLUSIONS: Polymorphisms in the genes coding for iron binding and transporting proteins, in the presence of local iron overload, might be responsible for suboptimal iron handling. This might account for the significant variability peculiar to MS phenotypes, particularly affecting MS risk and progression paving the way for personalized pharmacogenetic applications in the clinical practice

Polymorphisms of methylenetetrahydrofolate reductase (MTHFR) and susceptibility to pediatric acute lymphoblastic leukemia in a German study population

BACKGROUND: Methylenetetrahydrofolate reductase (MTHFR) has a major impact on the regulation of the folic acid pathway due to conversion of 5,10-methylenetetrahydrofolate (methylene-THF) to 5-methyl-THF. Two common polymorphisms (677C>T and 1298A>C) in the gene coding for MTHFR have been shown to reduce MTHFR enzyme activity and were associated with the susceptibility to different disorders, including vascular disease, neural tube defects and lymphoid malignancies. Studies on the role of these polymorphisms in the susceptibility to acute lymphoblastic leukemia (ALL) led to discrepant results. METHODS: We retrospectively evaluated the association of the MTHFR 677C>T and 1298A>C polymorphisms with pediatric ALL by genotyping a study sample of 443 ALL patients consecutively enrolled onto the German multicenter trial ALL-BFM 2000 and 379 healthy controls. We calculated odds ratios of MTHFR genotypes based on the MTHFR 677C>T and 1298A>C polymorphisms to examine if one or both of these polymorphisms are associated with pediatric ALL. RESULTS: No significant associations between specific MTHFR variants or combinations of variants and risk of ALL were observed neither in the total patient group nor in analyses stratified by gender, age at diagnosis, DNA index, immunophenotype, or TEL/AML1 rearrangement. CONCLUSION: Our findings suggest that the MTHFR 677C>T and 1298A>C gene variants do not have a major influence on the susceptibility to pediatric ALL in the German population

Custom CGH array profiling of copy number variations (CNVs) on chromosome 6p21.32 (HLA locus) in patients with venous malformations associated with multiple sclerosis

<p>Abstract</p> <p>Background</p> <p>Multiple sclerosis (MS) is a complex disorder thought to result from an interaction between environmental and genetic predisposing factors which have not yet been characterised, although it is known to be associated with the HLA region on 6p21.32. Recently, a picture of chronic cerebrospinal venous insufficiency (CCSVI), consequent to stenosing venous malformation of the main extra-cranial outflow routes (VM), has been described in patients affected with MS, introducing an additional phenotype with possible pathogenic significance.</p> <p>Methods</p> <p>In order to explore the presence of copy number variations (CNVs) within the HLA locus, a custom CGH array was designed to cover 7 Mb of the HLA locus region (6,899,999 bp; chr6:29,900,001-36,800,000). Genomic DNA of the 15 patients with CCSVI/VM and MS was hybridised in duplicate.</p> <p>Results</p> <p>In total, 322 CNVs, of which 225 were extragenic and 97 intragenic, were identified in 15 patients. 234 known polymorphic CNVs were detected, the majority of these being situated in non-coding or extragenic regions. The overall number of CNVs (both extra- and intragenic) showed a robust and significant correlation with the number of stenosing VMs (Spearman: r = 0.6590, p = 0.0104; linear regression analysis r = 0.6577, p = 0.0106).</p> <p>The region we analysed contains 211 known genes. By using pathway analysis focused on angiogenesis and venous development, MS, and immunity, we tentatively highlight several genes as possible susceptibility factor candidates involved in this peculiar phenotype.</p> <p>Conclusions</p> <p>The CNVs contained in the HLA locus region in patients with the novel phenotype of CCSVI/VM and MS were mapped in detail, demonstrating a significant correlation between the number of known CNVs found in the HLA region and the number of CCSVI-VMs identified in patients. Pathway analysis revealed common routes of interaction of several of the genes involved in angiogenesis and immunity contained within this region. Despite the small sample size in this pilot study, it does suggest that the number of multiple polymorphic CNVs in the HLA locus deserves further study, owing to their possible involvement in susceptibility to this novel MS/VM plus phenotype, and perhaps even other types of the disease.</p

FXIII e infarto del miocardio: un nuovo marker prognostico? Farmacogenetica e terapia personalizzata. (FAR 2010)

In Italia, al pari dei tassi europei emondiali, la principale causa di morte è rappresentata dalle malattie del sistema cardiovascolare (40% delle morti), superiore anche alle patologie tumorali (31,9% delle morti totali): Nonostante l’eccellente diagnosi e terapia post infarto del miocardio (MI), i major adverse cardiac events (MACE) e la progressione della lesione restano un punto critico anche in presenza di una efficace strategia riperfusiva (PCI) limitando la sopravvivenza a lungo termine. Il rimodellamento del ventricolo sinistro (LV) è la più comune causa di heart failure (HF) associata a prognosi negativa post-MI. L’espansione dell’area infartuata favorisce infatti dilatazione del LV, anomalo rimodellamento ed HF. Ottimizzare le fasi precoci di trattamento è un punto cruciale nel prevenire progressione, dilatazione e disfunzioni cardiache. Promuovere la guarigione del miocardio e ridurre l’espansione dell’infarto evita l’instaurarsi di una geometria alterata del ventricolo ed il progressivo rimodellamento. Ad oggi, pochissime terapie sono disponibili per migliorare la riparazione locale del cuore. Evidenze sperimentali in modelli murini suggeriscono che il fattore XIII della coagulazione (FXIII) gioca un ruolo chiave nella guarigione del miocardio e i suoi bassi livelli in circolo si associano a rottura cardiaca e morte post-infarto. Questi studi dimostrano l’importanza di idonei livelli di FXIII sulla sopravvivenza post-MI, sulla formazione di una cicatrice stabile, sullo spessore della cicatrice, sul contenimento dell’espansione dell’infarto e sulla dilatazione del LV. L’infarto determina una cicatrice fibrotica non contrattile e assottiglia ed espande l’area interessata. I livelli di FXIII sono bassi nel cuore di pazienti con rottura cardiaca, e riduzioni farmacologiche dei livelli di FXIII, come durante le terapie anticoagulanti, hanno impatto negativo sull’healing. Il nostro ed altri gruppi hanno dimostrato una fisiologica riduzione dei livelli di FXIII nella prima settimana post-MI. Questo è dovuto al ruolo del FXIII nell’angiogenesi, nella sintesi/deposizione di collagene e sull’attività delle MMPs come ampiamente dimostrato anche in altri modelli di riparazione tessutale (Zamboni & Gemmati, 2007). Inoltre, il nostro gruppo ha dimostrato che varianti geniche del FXIII, associate ad aumentata attività, riducono la mortalità cardiovascolare post-MI e l’incidenza di HF a un anno di follow-up. Abbiamo riportato dati simili in un altro modello di lesione (ulcere venose arti inferiori) in cui elevati livelli/attività di FXIII riducono l’estensione della lesione cutanea nella malattia cronica venosa. Lo scopo principale del progetto è valutare i livelli plasmatici di FXIII ogni 24 ore in pazienti durante i primi 6 giorni post-MI e correlarli con i classici parametri clinici e di laboratorio. In particolare, saranno confrontati livelli e cinetiche dei markers di lesione causati dall’infarto con i livelli di FXIII. Un follow-up a 30gg e ad un anno saranno eseguiti stratificando i pazienti per MACE. La curva di sopravvivenza sarà anche stratificata per livelli di FXIII e questo fornirà preziose informazioni prognostiche riconoscendo un livello soglia di FXIII al di sotto del quale si può prevedere una prognosi negativa considerando il paziente candidato a terapia sostitutiva con FXIII. Tutti i pazienti saranno genotipizzati per i principali polimorfismi del gene FXIII. Questo rivelerà relazioni tra genotipo, livelli di FXIII ed outcome clinico. Mentre la variante genica FXIII V34L è stata ampiamente studiata, poco si conosce sulle altre varianti e in particolare sulle combinazioni di queste nell’espressione del FXIII. Tali informazioni sono difficilmente ottenibili con studi di associazione in pazienti nei quali le combinazioni dei genotipi rari sono scarsamente rappresentate in omozigosi. Un altro punto cruciale del progetto sarà la caratterizzazione molecolare delle varianti del FXIII mediante espressione in vitro di molecole ricombinanti (r-FXIII) contenenti singole sostituzioni o loro combinazioni. Ci aspettiamo di chiarire la relazione tra genotipo del FXIII, livelli circolanti ed outcome clinico in pazienti con MI e di identificare gli effetti di specifiche sostituzioni aminoacidiche sull’espressione del FXIII. Questa informazione potrebbe suggerire un nuovo management clinico basato sulla farmacogenetica e nuove strategie terapeutiche, come la somministrazione di r-FXIII, volte a migliorare l’healing cardiaco in pazienti selezionati per alto rischio di prognosi negativa. Metodi: i pazienti saranno reclutati dall’unita coronarica (UTIC) dell’Università di Ferrara. All’arruolamento (t0) e ogni 24 ore per i 5 giorni successivi (t1-5) verrà eseguito un prelievo di sangue e il plasma rapidamente congelato. Un campione di controllo sarà prelevato al 30° giorno (t30) per avere i livelli basali di FXIII. I criteri d’inclusione saranno in accordo alla dettagliata descrizione precedentemente riportata (Gemmati et al; Mol Med, 2007). Lo studio è già stato approvato dal Comitato Etico. Il follow-up clinico, i test di valutazione dei livelli di FXIII dei pazienti arruolati e l’analisi statistica globale saranno eseguiti come già riportato (Gemmati et al; Mol Med, 2007). Follow-up: L’endpoint primario è la combinazione di morte cardiovascolare, reinfarto e heart failure (HF) a 30 giorni e ad un anno