A Possible Role for Arylsulfatase G in Dermatan Sulfate Metabolism.

Perturbations of glycosaminoglycan metabolism lead to mucopolysaccharidoses (MPS)-lysosomal storage diseases. One type of MPS (type VI) is associated with a deficiency of arylsulfatase B (ARSB), for which we previously established a cellular model using pulmonary artery endothelial cells with a silenced ARSB gene. Here, we explored the effects of silencing the ARSB gene on the growth of human pulmonary artery smooth muscle cells in the presence of different concentrations of dermatan sulfate (DS). The viability of pulmonary artery smooth muscle cells with a silenced ARSB gene was stimulated by the dermatan sulfate. In contrast, the growth of pulmonary artery endothelial cells was not affected. As shown by microarray analysis, the expression of the arylsulfatase G (ARSG) in pulmonary artery smooth muscle cells increased after silencing the arylsulfatase B gene, but the expression of genes encoding other enzymes involved in the degradation of dermatan sulfate did not. The active site of arylsulfatase G closely resembles that of arylsulfatase B, as shown by molecular modeling. Together, these results lead us to propose that arylsulfatase G can take part in DS degradation; therefore, it can affect the functioning of the cells with a silenced arylsulfatase B gene.

Mucopolysaccharidosis type VI in Russia, Kazakhstan, and Central and Eastern Europe.

BACKGROUND: The aim of this study was to describe the natural clinical course, incidence and prevalence of mucopolysaccharidosis type VI (MPS VI) in Russia, Kazakhstan, and Central and Eastern Europe. METHODS: Patients (n = 49) were identified by retrieving the data from eight international centers for MPS VI. RESULTS: A large number of patients presented with an attenuated phenotype (33%). Height and genotype were related to the severity of the disease, while no clear trend was observed between height and urinary glycosaminoglycan level. A high prevalence of the p.R152W mutation was observed both in the whole series (42%) as well as in Russian patients (43%). The incidence rate ranged from 0.0363 to 0.64 per 100,000 live births in Poland and Lithuania, respectively. CONCLUSIONS: The observed high p.R152W carrier frequency in the Lithuanian population may indicate a possible founder effect in this region. The high prevalence of this mutation observed in the whole series, as well as the Slavic origin of the majority of patients homozygous for this mutation, suggest that p.R152W may be of Slavic, not Lithuanian origin. Resettlement of the Polish population after World War II resulted in dilution of the prevalence of carriers in Poland and a very low MPS VI incidence.

Mucopolysaccharidosis type VI: a predominantly cardiac phenotype associated with homozygosity for p.R152W mutation in the ARSB gene.

Mucopolysaccharidosis type VI (MPS VI) is a rare lysosomal, autosomal recessive storage disorder caused by deficient activity of N-acetylgalactosamine-4-sulfatase (ARSB). Approximately, 140 ARSB gene mutations have been identified; however, most are private mutations making genotype-phenotype correlation for most MPS VI patients difficult. The aim of this study was to describe the natural clinical course in patients homozygous for the p.R152W mutation from eight unrelated families. From our database of 70 patients with MPS VI, we selected 10 patients homozygous for the p.R152W mutant allele (median age 27.5 years, range 18-38 years). We performed a cross-sectional observational study characterizing the onset and prevalence of clinical manifestations. First signs of the disease, such as cardiac valve disease, slightly decreased joint range of motion and mild growth retardation, were observed in mid-adolescent years (median 15 years). Within the disease course, the most common clinical feature in all the patients was progressive heart disease of predominantly valve origin leading to symptoms of heart failure. Other typical MPS VI features were subtle and not present in all the patients. Delays up to 23 years (median 8.5 years) intervened between symptom onset and disease diagnosis. Patients homozygous for the p.R152W mutation present a cardiac variant of MPS VI characterized by progressive cardiac valve disease leading to serious cardiac complications including abrupt death due to cardiac failure.

Assessing Trustworthy AI in Times of COVID-19: Deep Learning for Predicting a Multiregional Score Conveying the Degree of Lung Compromise in COVID-19 Patients.

This article's main contributions are twofold: 1) to demonstrate how to apply the general European Union's High-Level Expert Group's (EU HLEG) guidelines for trustworthy AI in practice for the domain of healthcare and 2) to investigate the research question of what does "trustworthy AI" mean at the time of the COVID-19 pandemic. To this end, we present the results of a post-hoc self-assessment to evaluate the trustworthiness of an AI system for predicting a multiregional score conveying the degree of lung compromise in COVID-19 patients, developed and verified by an interdisciplinary team with members from academia, public hospitals, and industry in time of pandemic. The AI system aims to help radiologists to estimate and communicate the severity of damage in a patient's lung from Chest X-rays. It has been experimentally deployed in the radiology department of the ASST Spedali Civili clinic in Brescia, Italy, since December 2020 during pandemic time. The methodology we have applied for our post-hoc assessment, called Z-Inspection®, uses sociotechnical scenarios to identify ethical, technical, and domain-specific issues in the use of the AI system in the context of the pandemic.

Mucopolysaccharidosis type VI (Maroteaux-Lamy syndrome) with a predominantly cardiac phenotype.

We present here the first literature description of a predominantly cardiac phenotype in a patient homozygous for missense mutation p.R152W in the N-acetylogalactosamine-4-sulfatase (arylsulfatase B, ARSB) gene. An adult Caucasian woman, who displayed very few symptoms up to her late thirties, was diagnosed with mucopolysaccharidosis type VI (MPS VI) after her hospitalization due to acute heart failure originating mainly from valve disease. In addition to her cardiac phenotype some musculoskeletal involvement without other MPS characteristic features were found. Despite the common pharmacologic treatment and implementation of enzyme replacement therapy with galsulfase the patient died at the age of 38 years because of decompensation of chronic heart failure.

Prognostic significance of hyperuricemia in patients with different types of renal dysfunction and acute myocardial infarction treated with percutaneous coronary intervention.

AIM: This study evaluated the impact of hyperuricemia (HUR) on outcome in patients with different types of impaired renal function (IRF) and acute myocardial infarction (AMI) treated invasively. METHODS: Out of 3,593 consecutive AMI patients treated invasively, 1,015 IRF patients were selected. The IRF group consisted of patients with baseline kidney dysfunction (BKD group) and/or patients with contrast-induced nephropathy (CIN group). HUR was defined as a serum uric acid concentration (SUAC) >420 µmol/l (>7 mg/dl). Independent predictors of death and major adverse cardiovascular events (MACE) were selected by the multivariate Cox-regression model. RESULTS: Remote mortality rates were higher in HUR patients: IRF (32.7 vs. 18.6%), BKD (41.3 vs. 25.9%), CIN (35.4 vs. 16.7%); all p < 0.001. HUR was an independent predictor of death in BKD (hazard ratio (HR) 1.38, p < 0.05). Each 100-µmol/l increase in SUAC was associated with a significant increase of HR for mortality: 1.087 in IRF patients, 1.108 in BKD patients, 1.128 in CIN patients; all p < 0.05. Remote major adverse cardiovascular event rates were higher in HUR patients: IRF (55.4 vs. 48.9%), CIN (56.8 vs. 48%); both p < 0.05. CONCLUSIONS: In AMI patients treated invasively, an increase in SUAC is an independent predictor of death within all types of renal dysfunction; HUR defined as SUAC >420 µmol/l (>7 mg/dl) is a predictor only in BKD patients.

Optimization of nonviral transfection: variables influencing liposome-mediated gene transfer in proliferating vs. quiescent cells in culture and in vivo using a porcine restenosis model.

Cationic liposomes/DNA complexes are widely used vectors for delivering genes in clinical and experimental trials. Relatively low transfer efficiencies in vivo compared with viral gene transfer may be improved using local application. In addition, markedly increased transfer efficiency may be achieved in vitro and in vivo via optimization of known variables influencing liposomal transfection. Lipofection under different conditions was performed in various cell lines and primary porcine smooth muscle cells. Optimized conditions found in vitro were verified in vivo using a porcine restenosis model. Toxicity was monitored analyzing cell metabolism. Transfer efficiency and safety were determined using morphometry, histology, galactosidase assays, PCR, and RT-PCR. The most important variables enabling maximum transfer efficiency were firstly the appropriate selection of cationic lipids for the cell type to be transfected, secondly the DNA/liposome ratio chosen, which depended on the cell type and cationic lipids used, and thirdly the state of proliferation of the targeted cells. Transfection in vivo demonstrated two- to fivefold higher transfer efficiencies when transfer conditions were extrapolated from optimization experiments in stationary cells compared with the use of conditions established in proliferating cells. Application of the therapeutic gene for cecropin using optimized transfer conditions resulted in a significantly reduced neointima formation compared with the transfection using a control gene for ss-galactosidase. Thus, in this vascular model, initial optimization of lipofection in stationary cells in culture followed by local delivery in vivo and with selection of a suitable therapeutic gene led to markedly improved transfer efficiencies, gene expression, and biological effect. Stationary cell cultures simulate more realistically the in vivo situation and may therefore represent a better model for future in vivo experiments. In addition, the advantages of liposomes are easy handling, low toxicity, and the lack of carcinogenicity or immunogenic reactions.

Prevalence rates of mucopolysaccharidoses in Poland.

The aim of this study was to determine the prevalence rates of mucopolysaccharidoses in Poland and to compare them with other European countries. A retrospective epidemiological survey covering the period between 1970 and 2010 was implemented. Multiple ascertainment sources were used to identify affected patients. The overall prevalence of mucopolysaccharidoses in the Polish population was 1.81 per 100,000. Five different mucopolysaccharidoses were diagnosed in a total of 392 individuals. MPS III was the most frequent mucopolysaccharidosis, with a birth prevalence of 0.86 per 100,000 live births. A prevalence of approximately 0.22 cases per 100,000 births was obtained for MPS I. For MPS II, the prevalence was estimated as 0.45 cases per 100,000 births; for MPS IV A and B as 0.14 cases in 100,000 births; and that for MPS VI as 0.03 cases per 100,000 births. 1. The prevalence pattern of mucopolysaccharidosis in Poland is lower when compared to the prevalence reported for other European countries, such as the Netherlands, Czech Republic, or Germany, but similar to countries like Sweden and Denmark. 2. Different frequencies of the various forms of mucopolysaccharidosis were observed. 3. In the case of MPS VI, the incidence values for Poland were the lowest of all the studies previously published so far.

Human pulmonary artery endothelial cells in the model of mucopolysaccharidosis VI present a prohypertensive phenotype.

BACKGROUND: Mucopolysaccharidosis type VI (MPS VI) is an autosomal recessive lysosomal disorder caused by a deficient activity of N-acetylgalactosamine-4-sulfatase (ARSB). Pulmonary hypertension (PH) occurs in MPS VI patients and is a marker of bad prognosis. Malfunction of endothelium, which regulates vascular tonus and stimulates angiogenesis, can contribute to the occurrence of PH in MPS VI. AIM: The aim of the study was to establish a human MPS VI cellular model of pulmonary artery endothelial cells (HPAECs) and evaluate how it affects factors that may trigger PH such as proliferation, apoptosis, expression of endothelial nitric oxide synthase (eNOS), natriuretic peptide type C (NPPC), and vascular endothelial growth factor A (VEGFA). RESULTS: Increasing concentrations of dermatan sulfate (DS) reduce the viability of the cells in both ARSB deficiency and controls, but hardly influence apoptosis. The expression of eNOS in HPAECs is reduced up to two thirds in the presence of DS. NPPC shows a biphasic expression reaction with an increase at 50 µg/mL DS and reduction at 0 and 100 µg/mL DS. The expression of VEGFA decreases with increasing DS concentrations and absence of elastin, and increases with increasing DS in the presence of elastin. CONCLUSION: Our data suggest that MPS VI endothelium presents a prohypertensive phenotype due to the reduction of endothelium's proliferation ability and expression of vasorelaxing factors.

Vascular endothelial growth factor response in porcine coronary and peripheral arteries using nonsurgical occlusion model, local delivery, and liposome-mediated gene transfer.

Angiogenesis and arteriogenesis play an important role in advanced vascular occlusive diseases. Whether angiogenesis or arteriogenesis predominate depends on the preexisting collateral vessel network, the type and location of occlusion, and different developmental origin of the arteries. Angiogenesis and arteriogenesis were investigated following vascular endothelial growth factor (VEGF) treatment in different arteries important in occlusive arterial diseases using a newly developed porcine arterial occlusion model. Porcine coronary and peripheral arteries were occluded interventionally using blinded stent grafts. Gene transfer was performed using a needle injection catheter and cationic lipid DOCSPER as gene carrier. DNA and gene expression in arterial tissue was examined using polymerase chain reaction (PCR) and reverse transcriptase (RT)-PCR. Vessel development was determined by angiography, immunohistochemistry, and measurement of capillary density. The transfected gene and its expression were found 3 months following application. In tissue adjacent to coronary arteries, there was significantly enhanced capillary density but no increase in angiographic score. In contrast, tissue surrounding peripheral arteries demonstrated no enhancement of capillary density but an enhancement in angiographic score. These results demonstrate differential responses to VEGF treatment in coronary and peripheral arteries resulting predominantly in either angiogenesis or arteriogenesis. Further investigation of VEGF signaling pathway is necessary for better understanding of the processes of vascular development, which may have potential impact on the design of cardiovascular therapeutics.

Mucopolysaccharidosis type VI: a cardiologist's guide to diagnosis and treatment.

Mucopolysaccharidosis type VI (MPS VI, Maroteaux-Lamy syndrome) is an inborn error of metabolism, with incidences at birth ranging from 1 in 1.5 million to 1 in 43,000 live births. This disorder is rarely considered when evaluating patients with common populational cardiovascular diseases. A significant number of MPS VI patients, however, do present cardiovascular disease and MPS VI should be considered as a potential differential diagnosis for other cardiovascular disorders. This article reviews the clinical features, diagnostic tests and treatment options for MPS VI. Although MPS VI affects many organs and systems of the human body this review focuses on MPS VI diseases of the heart and vessels. The most characteristic cardiac presentation of MPS VI is valvular disease, but heart failure, pulmonary hypertension, cardiomyopathy, fibroelastosis and cardiac conduction system disorders may also occur. Cardiovascular disease in MPS VI patients may emerge silently. An early diagnosis is difficult due to joint stiffness, respiratory system involvement or skeletal malformations that limit exercise capacity and mask the underlining heart failure. This article is supposed to serve as a very practical reference for cardiologists who may come across MPS VI in their daily practices. A greater awareness of cardiovascular manifestations of MPS VI among cardiologists can help to reduce misdiagnosis and promote early detection of this inborn disorder and aid the implementation of adequate therapy at the earliest stage possible which is crucial for its efficacy.

Cardiovascular manifestations of mucopolysaccharidosis type VI (Maroteaux-Lamy syndrome).

The aim of the article is to gather and summarize the published data about the incidence, course of illness, treatment possibilities and complications of cardiovascular disorders in patients with mucopolysaccharidosis type VI (MPS VI) also known as Maroteaux-Lamy syndrome. MPS VI is a lysosomal storage disorder caused by deficient activity of N-acetylogalactosamine-4-sulfatase leading to progressive intracellular accumulation of glycosaminoglycans. The relatively low birth prevalence ranging from 1 in 43,000 to 1 in 1.5 million births mirrors the limited descriptions of the cardiovascular disorders in the medical literature. Patients with MPS VI can be specifically treated with enzyme replacement therapy. Extra-cardiac features include growth retardation, coarse facial features, stiff joints, skeletal malformations (dysostosis multiplex), respiratory problems, corneal clouding, and hepatosplenomegaly. The clinical presentation varies considerably, however the development of heart disease and cardiac dysfunction is a serious problem in the majority of patients. The most characteristic cardiac presentation is valvular disease, while other MPS VI patients also develop cardiomyopathy, fibroelastosis, pulmonary hypertension, cardiac conduction system disorders and other complications. There are also reports on acute heart failure. Early cardiovascular manifestation may escape detection since joint stiffness or skeletal malformations limit maximal exercise levels and respiratory system involvement may mask the underlining cardiac insufficiency. A correct and timely diagnosis offers the possibility of disease-specific treatment leading to sustained clinical benefits for cardiac and non-cardiac MPS VI manifestations.

Small poly-L-lysines improve cationic lipid-mediated gene transfer in vascular cells in vitro and in vivo.

The potential of two small poly-L-lysines (sPLLs), low molecular weight sPLL (LMW-L) containing 7-30 lysine residues and L18 with 18 lysine repeats, to enhance the efficiency of liposome-mediated gene transfer (GT) with cationic lipid DOCSPER [1,3-dioleoyloxy-2-(N(5)-carbamoyl-spermine)-propane] in vascular smooth muscle cells (SMCs) was investigated. Dynamic light scattering was used for determination of particle size. Confocal microscopy was applied for colocalization studies of sPLLs and plasmid DNA inside cells. GT was performed in proliferating and quiescent primary porcine SMCs in vitro and in vivo in porcine femoral arteries. At low ionic strength, sPLLs formed small complexes with DNA (50-100 nm). At high ionic strength, large complexes (>1 microm) were observed without any significant differences in particle size between lipoplexes (DOCSPER/DNA) and lipopolyplexes (DOCSPER/sPLL/DNA). Both sPLLs were colocalized with DNA inside cells 24 h after transfection, protecting DNA against degradation. DOCSPER/sPLL/DNA formulations enhanced GT in vitro up to 5-fold, in a porcine model using local periadventitial application up to 1.5-fold. Both sPLLs significantly increased liposome-mediated GT. Poly-L-lysine L18 was superior to LMW-L since it enabled maximal GT at a 10-fold lower concentration. Thus, sPLLs may serve as enhancers for GT applications in SMCs in vitro and in vivo using local delivery.

Vascular endothelial growth factor (VEGF165) and its influence on angiogenesis versus arteriogenesis in different vascular beds.

PURPOSE: To use local gene delivery to determine any district-specific influence of vascular endothelial growth factor (VEGF(165)) on angiogenesis and arteriogenesis in arteries of distinct developmental origin. METHODS: Coronary and peripheral arteries were chronically occluded in 30 Pietrain pigs using a percutaneous approach and blinded stent-graft. DNA was delivered to the adventitia in dosages corresponding to 10% of the body weight-adapted amount used in clinical trials. The coronary arteries in 12 animals and the peripheral arteries in 12 animals were treated or used as controls (no occlusion or occlusion with transfection of the beta-galactosidase gene). Six additional animals were sacrificed at 1 or 3 weeks for expression analyses, while the other 24 animals were sacrificed at 5 months for expression analysis and histology. Angiography, polymerase chain reaction analyses, and immunohistochemistry were performed. RESULTS: Expression of the VEGF gene was observed at 1 and 3 weeks following application, while transfected DNA was detected up to 5 months. New collaterals formed around occluded coronary arteries (2.63 +/- 0.69 fold, p<0.05 versus 1.24 +/- 0.40 fold for peripheral arteries), and angiographic arterial area increase was more pronounced in coronary (2.49 +/- 0.59 fold, p<0.05) than peripheral arteries (1.49 +/- 0.05 fold). There was no collateralization surrounding occluded peripheral arteries, but new arterial branches were seen (2.0 +/- 0.28, p<0.05 versus 1.07 +/- 0.31 for coronary). CONCLUSIONS: The response to VEGF, whether it is predominantly angiogenesis or arteriogenesis, is dependent on the target vessel. These observed differences in the behavior of arteries may be related to their differing developmental origins, which may have important implications for future therapeutic strategies using VEGF in different vessels.

Comparison of surgical versus endovascular occlusion models in pig femoral arteries.

PURPOSE: To compare an endovascular technique with a well established surgical approach to achieve long-term occlusions of large porcine arteries while preserving the integrity of periarterial tissue. METHODS: The femoral arteries in 11 pigs were occluded using surgical techniques on one side and blinded stent-grafts in the contralateral vessel. Feasibility, safety, primary and long-term success, and the extent of vascularization were determined over a 3-month period by conventional angiography and histological analysis. A subgroup of animals (n=5) was treated with a locally administered plasmid coding for vascular endothelial growth factor (pVEGF165) to compare both occlusion techniques under conditions of collateral growth induction. RESULTS: The primary and long-term success rates for both occlusion models were 100%. Surgical occlusion of arteries resulted in a significant amount of scar dehiscence and local groin infection compared to the endograft-occluded side. There was no significant difference in capillary densities and collateralization of periarterial areas in a comparison of the occlusion technique: the cross-sectional area of the superficial femoral artery (SFA) was 300 +/- 24 mm2 for endovascular occlusion versus 320 +/- 23 mm2 for surgical occlusion (p=0.559). In the profunda femoris artery, respective values were 418 +/- 35 and 448 +/- 18 mm2 (p=0.474). The local delivery of pVEGF165 resulted in a significant increase in collateral growth in both occlusion models with comparable neovascularization: cross-sectional SFA area increased from 310 +/- 16 to 428 +/- 13 mm2 (p<0.0001); in the PFA, the area increased from 422 +/- 19 to 658 +/- 49 mm2 (p<0.0001). CONCLUSIONS: Endovascular arterial occlusions using blinded stent-grafts allow easy and safe creation of long-term occlusions. Previously described collateralization following surgical occlusions was not observed, indicating that those collaterals may be associated with wound healing rather than ischemia. The occlusion of arteries using blinded stent-grafts in pigs may therefore be an appropriate model for assessing the effects of angiogenic factors in vivo.