Postnatal outcome of fetal aberrant right subclavian artery: a single center study

PURPOSE

This study aims to explore the correlation between fetal aberrant right subclavian artery (ARSA) and chromosomal disorders, with a specific focus on Down syndrome and DiGeorge syndrome.

METHODS

From November 2017 to February 2020, we conducted fetal anomaly screening and assessed the fetal heart in 8494 at our institution. The right subclavian artery tracing was assessed using Doppler ultrasonography following the 3-vessel and tracheal views (3VTV) in the fetal heart scan.

RESULTS

ARSA was found in 31 fetuses, which accounts for 0.36% of the total of 8494 fetuses. 96.8% of fetuses with ARSA were found to have normal chromosomal analysis. We identified only one case of trisomy 21 as the chromosomal condition present. In 80% of the identified ARSA, there were no additional associated findings.

CONCLUSION

ARSA is a rare condition that often does not manifest any concomitant abnormalities. The majority of ARSA instances identified in the second trimester are euploid. If ARSA is the only sonographic finding during fetal anomaly screening and there are no maternal or laboratory risk factors, further evaluation with non-invasive diagnostics may be recommended. Non-invasive genetic testing may be used for additional investigation.

Neuro-Interventional Diagnosis and Treatment Using the Right Transradial Approach in Patients with Aberrant Right Subclavian Artery

OBJECTIVE

To assess the effectiveness and safety of neurological interventions using the right transradial approach (R-TRA) in patients with aberrant right subclavian artery (ARSA).

METHODS

We retrospectively analyzed cases that underwent cerebral angiography and interventions at Huangpi District People's Hospital from January 2023 to July 2023. Out of 335 cases, 5 patients with ARSA were identified.

RESULTS

All 5 cases underwent diagnostic cerebral angiography via R-TRA. Two of the patients received interventions via R-TRA: 1 underwent right internal carotid artery balloon dilation angioplasty, while another underwent left vertebral artery stenting. No surgery-related complications were observed during these procedures.

CONCLUSIONS

R-TRA proves to be a safe and effective option for neuro-interventional surgery in patients with ARSA.

Autophagy Proteins and clinical data reveal the prognosis of polycystic ovary syndrome

OBJECTIVE

We aimed to investigate the significance of autophagy proteins and their association with clinical data on pregnancy loss in polycystic ovary syndrome (PCOS), while also constructing predictive models.

METHODS

This study was a secondary analysis. we collected endometrial samples from 33 patients with polycystic ovary syndrome (PCOS) and 7 patients with successful pregnancy control women at the Reproductive Center of the Second Hospital of Lanzhou University between September 2019 and September 2020. Liquid chromatography tandem mass spectrometry was employed to identify expressed proteins in the endometrium of 40 patients. R was use to identify differential expression proteins(DEPs). Subsequently, Metascape was utilized for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. Multivariate Cox analysis was performed to analyze autophagy proteins associated with reproductive outcomes, while logistic regression was used for analyzing clinical data. Linear correlation analysis was conducted to examine the relationship between autophagy proteins and clinical data. We established prognostic models and constructed the nomograms based on proteome data and clinical data respectively. The performance of the prognostic model was evaluated by the receiver operating characteristic curve (ROC) and decision curve analysis (DCA).

RESULTS

A total of 5331 proteins were identified, with 450 proteins exhibiting significant differential expression between the PCOS and control groups. A prognostic model for autophagy protein was developed based on three autophagy proteins (ARSA, ITGB1, and GABARAPL2). Additionally, another prognostic model for clinical data was established using insulin, TSH, TPOAB, and VD3. Our findings revealed a significant positive correlation between insulin and ARSA (R = 0.49), as well as ITGB1 (R = 0.3). Conversely, TSH exhibited a negative correlation with both ARSA (-0.33) and ITGB1 (R = -0.26).

CONCLUSION

Our research could effectively predict the occurrence of pregnancy loss in PCOS patients and provide a basis for subsequent research.

Identification of a Novel ARSA Gene Mutation Through High-Throughput Molecular Diagnosis Method in Two Girls with Late Infantile Metachromatic Leukodystrophy

Metachromatic leukodystrophy (MLD) is a rare leukoencephalopathy caused by pathogenic mutations in the ARSA gene. It manifests as severe motor symptoms, mental problems, and sometimes, seizures. We aimed to investigate the phenotypic manifestations and genetic causes of MLD in an Iranian family. We present the case of a 3-year-old girl who presented with hypotonia, muscular atrophy, and seizures. Neurological and neuromuscular examinations were performed to evaluate clinical characteristics. Whole exome sequencing (WES) was used to detect disease-causing variants. In silico analysis was performed to predict the pathogenicity of this variant. GROMACS software was utilized for molecular dynamic simulation (MDS). Neurological studies revealed marked slowing of motor conduction velocities and an increased motor unit action potential duration. Brain MRI scan revealed white matter abnormalities. By applying WES, we identified a novel homozygous missense variant (NM_000487.6, c.938G > C, p.R313P) in ARSA. Direct sequencing identified this homozygous variant in her asymptomatic younger sister, whereas both parents carried a heterozygous variant. This mutation has not been reported in genetic databases or in literature. In silico analysis predicted that any variation in this DNA position would cause disease, as it is highly conserved. The c.938G > C variant was classified as a pathogenic variant according to ACMG/AMP guidelines. MDS analysis indicated that c.938G > C had a significant impact on both the structure and stabilization of ARSA, ultimately resulting in impaired protein function. The identification of this variant expands the spectrum of ARSA gene mutations associated with MLD and highlights the importance of genetic testing for the diagnosis of MLD.

Perinatal Diagnosis and Management of a Case with Interrupted Aortic Arch, Pulmonary Valve Dysplasia and 22q11.2 Deletion: A Case Report

The 22q11.2 deletion syndrome (22q11.2DS) is the most common chromosomal microdeletion disorder caused by hemizygous microdeletion of the long arm of chromosome 22. It is now known to have a heterogenous presentation that includes multiple additional congenital anomalies and later-onset conditions, such as gastrointestinal and renal abnormalities, autoimmune disease, variable cognitive delays, behavioral phenotypes and psychiatric illness. The purpose of our paper is to present the case of a fetus diagnosed with a complex association of cardiac anomalies: interrupted aortic arch type B, large malalignment-type ventricular septal defect, pulmonary valve dysplasia, and aberrant right subclavian artery for whom the result of genetic testing revealed 22q11.2 deletion. The pregnancy was regularly followed until delivery which took place in Germany so that neonatal cardiac surgery could be performed in an experienced center for cardiac malformations. The distinctivness of our report resides in the fact that it offers a complete image of a case of 22q11.2 deletion syndrome starting from the prenatal diagnosis (and emphasizing on the most relevant sonographic features) and, with parents not opting for termination of pregnancy, ending with the newborn surviving major cardiac surgery, offering thus the possibility to bring into focus postnatal outcome and future expectations in similar cases.

Association of Rare Variants in ARSA with Parkinson's Disease

BACKGROUND

Several lysosomal genes are associated with Parkinson's disease (PD), yet the association between PD and ARSA remains unclear.

OBJECTIVES

To study rare ARSA variants in PD.

METHODS

To study rare ARSA variants (minor allele frequency < 0.01) in PD, we performed burden analyses in six independent cohorts with 5801 PD patients and 20,475 controls, followed by a meta-analysis.

RESULTS

We found evidence for associations between functional ARSA variants and PD in four cohorts (P ≤ 0.05 in each) and in the meta-analysis (P = 0.042). We also found an association between loss-of-function variants and PD in the United Kingdom Biobank cohort (P = 0.005) and in the meta-analysis (P = 0.049). These results should be interpreted with caution as no association survived multiple comparisons correction. Additionally, we describe two families with potential co-segregation of ARSA p.E382K and PD.

CONCLUSIONS

Rare functional and loss-of-function ARSA variants may be associated with PD. Further replications in large case-control/familial cohorts are required. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Fenestrated Physician-Modified Endovascular Grafts for Aberrant Right Subclavian Artery and/or Kommerell's diverticulum

OBJECTIVE

The aim of this case series is to report feasibility, efficiency, and safety of fenestrated physician-modified endografts (PMEGs) in aortic arch pathologies with aberrant right subclavian artery (ARSA) and/or Kommerell's diverticulum (KD).

METHODS

All consecutive patients with ARSA and/or KD who underwent hybrid aortic arch repair combined with homemade fenestrated stent-graft from 2018 to 2022 were reviewed.

RESULTS

Six patients with ARSA and/or KD underwent hybrid surgery for aortic repair, 4 of whom were men, with a mean age of 49 years. Furthermore, 2 of them were symptomatic with dysphagia, 1 was taken in emergency, 1 had a bovine arch and a KD, and 2 had right descending thoracic aortas. The mean operation time was 138 (111-216) minutes. In addition, 83% of the homemade grafts were double fenestrated. All the proximal landings were in zone 0; the mean proximal aortic diameter was 29 (23-34) mm. The range of diameters for the endografts were 24 to 38 mm. There was a 100% technical success, with 0% 30 days mortality, no stroke, and no endoleak. During the follow-up, no aortic-related death or secondary intervention was required and all supra-aortic vessels remain patent.

CONCLUSION

Hybrid aortic arch repair, with fenestrated PMEGs for ARSA and/or KD, is associated with acceptable early and midterm major morbidity and mortality.

CLINICAL IMPACT

This retrospective case series analyzed outcomes in 6 patients with an aberrant right subclavian artery and/or Kommerell's diverticulum treated with fenestrated PMEGs during an average 16 month follow-up. The case series suggests that the use of these fenestrated PMEGs for the management of patients with an aberrant right subclavian artery is a safe, effective and durable method in the medium-term.

Whole exome sequencing identified five novel variants in CNTN2, CARS2, ARSA, and CLCN4 leading to epilepsy in consanguineous families

Introduction: Epilepsy is a group of neurological disorders characterized by recurring seizures and fits. The Epilepsy genes can be classified into four distinct groups, based on involvement of these genes in different pathways leading to Epilepsy as a phenotype. Genetically the disease has been associated with various pathways, leading to pure epilepsy-related disorders caused by CNTN2 variations, or involving physical or systemic issues along with epilepsy caused by CARS2 and ARSA, or developed by genes that are putatively involved in epilepsy lead by CLCN4 variations. Methods: In this study, five families of Pakistani origin (EP-01, EP-02, EP-04, EP-09, and EP-11) were included for molecular diagnosis. Results: Clinical presentations of these patients included neurological symptoms such as delayed development, seizures, regression, myoclonic epilepsy, progressive spastic tetraparesis, vision and hearing impairment, speech problems, muscle fibrillation, tremors, and cognitive decline. Whole exome sequencing in index patients and Sanger sequencing in all available individuals in each family identified four novel homozygous variants in genes CARS2: c.655G>A p.Ala219Thr (EP-01), ARSA: c.338T>C: p.Leu113Pro (EP-02), c.938G>T p.Arg313Leu (EP-11), CNTN2: c.1699G>T p.Glu567Ter (EP-04), and one novel hemizygous variant in gene CLCN4: c.2167C>T p.Arg723Trp (EP-09). Conclusion: To the best of our knowledge these variants were novel and had not been reported in familial epilepsy. These variants were absent in 200 ethnically matched healthy control chromosomes. Three dimensional protein analyses revealed drastic changes in the normal functions of the variant proteins. Furthermore, these variants were designated as "pathogenic" as per guidelines of American College of Medical Genetics 2015. Due to overlapping phenotypes, among the patients, clinical subtyping was not possible. However, whole exome sequencing successfully pinpointed the molecular diagnosis which could be helpful for better management of these patients. Therefore, we recommend that exome sequencing be performed as a first-line molecular diagnostic test in familial cases.

Transcatheter aortic valve implantation causing left ventricular perforation may be associated with an aberrant right subclavian artery: a case report

Left ventricular perforation is an uncommon complication in transcatheter aortic valve implantation (TAVI). And a case of left ventricular perforation associated with an aberrant right subclavian artery (ARSA) has rarely been reported. An 86-year-old female attended our hospital with symptomatic severe aortic stenosis. Because of the patient's advanced age, and that she was a long-term steroid user, we treated her using TAVI. Although the presence of ARSA was noted, the aortic arch was a smooth arc on images of computed tomography (CT) along the axis of the aortic arch. A trans-femoral TAVI was performed. When the TAVI device passed through the aortic arch, the angle of the delivery system suddenly changed, and the guidewire was pushed in, which caused left ventricular perforation. We had to open the chest and perform a repair procedure. There was an enlarged space at the ARSA origin in three-dimensional (3D) CT, and this space may have caused the unexpected guidewire movement. The TAVI device may move in unexpected ways in presence of ARSA. It is necessary to carefully evaluate the access route using 3D CT as part of the preoperative evaluation to determine the safest treatment strategy.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12055-022-01429-9.

An Aberrant Right Subclavian Artery-Esophageal Fistula-A Fatal Complication of a Common Anomaly: A Case Report and Review of Literature

An aberrant right subclavian artery (ARSA), also called as arteria lusoria, is one of the most common aortic arch anomalies. ARSA-esophageal fistula is a rare, life-threatening complication, with only 37 cases reported in literature. We describe a case of a young girl who developed acute episode of massive hematemesis after the recovery from novel coronavirus disease 2019 (COVID-19) pneumonia. Computed tomography (CT) angiography showed ARSA with retroesophageal course and active contrast leak in esophagus. Digital subtraction angiography confirmed the site of active contrast extravasation from the ARSA. However, the patient succumbed to hypovolemic shock even before the endovascular or surgical interventions could be done.

Prenatal diagnosis of aberrant right subclavian artery: a literature review

The primary aim of this review is to estimate the prevalence of ARSA both in euploid fetuses as well as in fetuses with Down Syndrome. Secondary objectives were to estimate the association of ARSA with cardiac anomalies and chromosomal defects, especially trisomy 21 and 22q11 deletion (DiGeorge Syndrome). The incidence of ARSA in normal population varies from 0.35% to 3.5%, based on different studies. Since the first reported association between ARSA and trisomy 21 in 2015 until today, several studies have emerged to confirm different degrees of this correlation. Indeed, ARSA appears to be a clinically useful prenatal ultrasound marker for trisomy 21. Particularly, most recent studies concluded that ARSA as a non-isolated finding can be used as screening for Down syndrome. However, when ARSA is an isolated finding, various studies proved that there is no significant correlation with Down syndrome. Apart from these, ARSA appears to be associated with other chromosomal abnormalities, such as 22q11 deletion, cardiac defects and other morphological anomalies. As a conclusion ARSA should be characterized as isolated or non-isolated, as the non - isolated ARSA appears to be a clinically useful marker of Down syndrome and thus, additional testing is required when diagnosed.

Bioinformatic Approach to Unveil Key Differentially Expressed Proteins in Human Sperm After Slow and Rapid Cryopreservation

Currently, two conventional freezing techniques are used in sperm cryopreservation: slow freezing (SF) and rapid freezing (RF). Despite the protocolar improvements, cryopreservation still induces significant alterations in spermatozoon that are poorly understood. Here, available proteomic data from human cryopreserved sperm was analyzed through bioinformatic tools to unveil key differentially expressed proteins (DEPs) that can be used as modulation targets or quality markers. From the included proteomic studies, 160 and 555 DEPs were collected for SF and RF groups, respectively. For each group, an integrative network was constructed using gene ontology and protein-protein interaction data to identify key DEPs. Among them, arylsulfatase A (ARSA) was highlighted in both freezing networks, and low ARSA levels have been associated with poor-sperm quality. Thus, ARSA was selected for further experimental investigation and its levels were assessed in cryopreserved samples by western blot. ARSA levels were significantly decreased in RF and SF samples (∼31.97 and ∼39.28%, respectively). The bioinformatic analysis also revealed that the DEPs were strongly associated with proteasomal and translation pathways. The purposed bioinformatic approach allowed the identification of potential key DEPs in freeze-thawed human spermatozoa. ARSA has the potential to be used as a marker to assess sperm quality after cryopreservation.

Combination of kaempferol and azithromycin attenuates Staphylococcus aureus-induced osteomyelitis via anti-biofilm effects and by inhibiting the phosphorylation of ERK1/2 and SAPK

Osteomyelitis is bacterial infection of bone, commonly caused by Staphylococcus aureus. This work aims to study the potential of azithromycin and kaempferol against chronic osteomyelitis induced by azithromycin-resistant Staphylococcus aureus (ARSA). It was noticed that rats tolerated the treatments with no diarrhoea or weight loss; also, no deaths were observed in rats. The treatment by azithromycin alone failed to inhibit bacterial growth and also had no effect on the infection condition of bone, although the treatment decreased the levels of interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α), but did not improve the oxidative stress levels. Kaempferol monotherapy slightly inhibited bacterial growth and bone infection; the treatment also inhibited the levels of IL-6 and (TNF-α). The treatment also improved the antioxidant status. However, the combined treatment of azithromycin and kaempferol significantly suppressed bacterial growth and bone infection and modulated oxidative stress. In vitro, the combined treatment inhibited the levels of IL-6 and TNF-α, and also suppressed the phosphorylation of ERK1/2 and stress-activated protein kinase (SAPK). The combined treatment also showed anti-biofilm activity in ARSA. The combination attenuates ARSA-induced osteomyelitis in rats compared with their treatments alone by reducing oxidative stress, inhibiting the phosphorylation of ERK1/2 and SAPK and inhibiting biofilm formation.

Aberrant right subclavian artery leading to prenatal diagnosis of Koolen de Vries syndrome

Koolen de Vries syndrome is a rare genetic disorder with an estimated prevalence 1:16000 in the general population but it is considered to be an underdiagnosed syndrome. We report a 17q21.31 microdeletion which was diagnosed prenatally in a fetus with aberrant right subclavian artery (ARSA). Koolen de Vries syndrome is a rare chromosomal abnormality and according to the literature this is the first case in which the detection of ARSA led to this syndrome.

Evaluating the role of ARSA in Chinese patients with Parkinson's disease

Recent studies have suggested ARSA, a gene responsible for metachromatic leukodystrophy, could be a genetic modifier of Parkinson's disease (PD) pathogenesis, acting as a molecular chaperone for α-synuclein. To elucidate the role of ARSA variants in PD, we did a comprehensive analysis of ARSA variants by performing next-generation sequencing on 477 PD families, 1440 sporadic early-onset PD patients and 1962 sporadic late-onset PD patients and 2636 controls from Chinese mainland, as well as the association between ARSA variants and cognitive function of PD patients. We identified 2 familial PD following autosomal dominant inherence carrying rare variants of ARSA, but they had limited clinical significance. We detected a total of 81 coding variants of ARSA in our subjects but none of the identified variants were associated with either susceptibility or cognitive performance of PD, while loss-of-function variants showed slightly increased burden in late-onset PD (0.25% vs. 0%, p = 0.08). Our results suggested ARSA may not play important roles in PD of Chinese population.

Aberrant right subclavian artery: the association with chromosomal defects and the related post-natal outcomes in a third level referral centre

Aberrant right subclavian artery (ARSA) is the most common embryologic abnormality of the aortic arch. The presence of ARSA has been previously associated with an increased risk of Down syndrome. ARSA at birth may be associated with dysphagia, respiratory distress and stridor and there is no clear evidence-based management. The aim of this study was to describe the associations with chromosomal abnormalities and the postnatal outcome of fetuses diagnosed with ARSA. We analysed fetuses diagnosed antenatally with ARSA between January 2013 and September 2019 in the fetal echocardiography unit of the Hospital Monaldi, University 'Vanvitelli' of Naples, Italy. The results showed fifty fetuses diagnosed with ARSA, all confirmed after birth. The ARSA was an isolated finding in 46 fetuses (92%), while in 4 fetuses the ARSA was associated with other cardiac and/or extra-cardiac anomalies. Only one fetus was diagnosed with trisomy 21 (2%). In this fetus the ARSA was the only ultrasound anomaly identified. There were no cases necessitating referral due to the presence of compression symptoms at birth. The presence of ARSA was associated with trisomy 21 in the 2% of cases in our series and there were no neonatal complications due to airway compression at birth.IMPACT STATEMENTWhat is already known on this subject? Aberrant right subclavian artery (ARSA) is the most common embryologic abnormality of the aortich arch. ARSA at birth could be associated with dysphagia, respiratory distress and stridor and no evidence-based management of these fetuses has been described yet. The presence of ARSA has been previously associated with an increased risk of Down syndrome.What do the results of this study add? This study confirms known data on association with chromosomal defects and provides some original data on the absence of symptomatology due to tracheal compression with a postnatal follow-up up to three years of age.What are the implications of these findings for clinical practice and/or further research? Our findings suggest that in cases with adequate prenatal assessment performed by experienced clinicians, delivery can safely take place at local hospitals, with no need of referral soon after birth. The use of transthoracic echocardiography to confirm the diagnoses of ARSA after birth and to plan the next follow-up appointments can be supported.

Arylsulfatase A Remodeling during Human Sperm In Vitro Capacitation Using Field Emission Scanning Electron Microscopy (FE-SEM)

Capacitation drives sperm biophysical and biochemical changes for sperm-oocyte interactions. It is a well-known fact that the molecular complex arylsulfatase A (ARSA), hyaluronidase sperm adhesion molecule 1 (SPAM1), and heat shock protein 2 (HSPA2) plays a significant role in sperm-zona pellucida (ZP) binding. However, the time-dependent capacitation effects on the sperm surface ARSA presence and specific topographic distributions remain to be elucidated. Here, we quantified the ARSA density and specific membrane domain locations before (US) and after in vitro capacitation (one and four hours; CS1-CS4) in human sperm using high-resolution field emission scanning electron microscopy (FE-SEM) and immunogold labeling. Our results showed a significant and progressive capacitation-mediated increase of labeled spermatozoa from the US (37%) to CS4 (100%) physiological conditions. In addition, surface mapping revealed a close relationship between the ARSA residues and their acrosomal repositioning. Compared with the ARSA surface heterogeneous distribution found in US, the CS1-4 conditions exhibited clustering on the peri-acrosomal region, showing that time-dependent capacitation also induced a ARSA residue dramatic translocation on sperm surfaces. Our findings provide novel insights into the molecular remodeling events preceding sperm-oocyte interactions.

[Localization of Arylsulfatase A during in vitro incubation of human spermatozoa in capacitation media]

OBJECTIVE

To determine the localization and distribution of the ArylsulfataseA receptor (ARSA) in human spermatozoa before and after their incubation in capacitation medium for 1 and 4hours.

MATERIAL AND METHODS

Semen samples were obtained from five normozoospermic donors. Capacitation was by swim-up technique using capacitation medium for 1 and 4hours. Localization of the ARSA receptor was assessed by indirect immunofluorescence using confocal microscopy. A minimum of 200cells were observed in each physiological condition.

RESULTS

Before incubation, no representative pattern was observed among the cells positive for this biomarker (8.61%). This percentage increased significantly after incubation in the capacitation medium for 1 and 4hours (61.86% and 63.38% respectively). A majority pattern was observed among the capacitated cells, with intense labelling in the acrosomal region (27.11% and 28.20% after 1 and 4hours respectively). It should be noted that the pattern corresponding to fluorescence at the level of the periacrosomal region was not observed in the spermatozoa prior to incubation. Only after incubation in capacitation medium for 1 and 4hours, 9.13% and 12.78% of cells with such distribution were detected.

CONCLUSIONS

In vitro capacitation, regardless of time, favours the immunolocalization of ARSA in the cephalic region of the spermatozoa. The most representative subpopulation after this process was the one in which ARSA was intensely and homogeneously distributed in the acrosome region, involved in primary gamete recognition.

Comprehensive clinical, biochemical, radiological and genetic analysis of 28 Turkish cases with suspected metachromatic leukodystrophy and their relatives

Metachromatic leukodystrophy (MLD) is a glycosphingolipid storage disease caused by deficiency of the lysosomal enzyme arylsulfatase A (ASA) or its activator protein saposin B. MLD can affect all age groups in severity varying from a severe fatal form to milder adult onset forms. Diagnosis is usually made by measuring leukocyte ASA activity. However, this test can give false negative or false positive laboratory results due to pseudodeficiency of ASA and saposin B deficiency, respectively. Therefore, we aimed to evaluate patients with suspected MLD in a Turkish population by comprehensive clinical, biochemical, radiological, and genetic analyses for molecular and phenotypic characterization. We analyzed 28 suspected MLD patients and 41 relatives from 24 families. ASA activity was found to be decreased in 21 of 28 patients. Sixteen patients were diagnosed as MLD (11 late infantile, 2 juvenile and 3 adult types), 2 MSD, 2 pseudodeficiency (PD) and the remaining 8 patients were diagnosed as having other leukodystrophies. Enzyme analysis showed that the age of onset of MLD did not correlate with residual ASA activity. Sequence analysis showed 11 mutations in ARSA, of which 4 were novel (p.Trp195GlyfsTer5, p.Gly298Asp, p.Arg301Leu, and p.Gly311Asp), and 2 mutations in SUMF1 causing multiple sulfatase deficiency, and confirmed the diagnosis of MLD in 2 presymptomatic relatives. All individuals with confirmed mutations had low ASA activity and urinary sulfatide excretion. Intra- and inter-familial variability was high for the same ARSA missense genotypes, indicating the contribution of other factors to disease expression. Imaging findings were evaluated through a modified brain MRI scoring system which indicated patients with protein-truncating mutations had more severe MRI findings and late-infantile disease onset. MRI findings were not specific for the diagnosis. Anti-sulfatide IgM was similar to control subjects, and IgG, elevated in multiple sulfatase deficiency. In conclusion, the knowledge on the biochemical, clinical and genetic basis of MLD was expanded, a modified diagnostic laboratory algorithm for MLD based on integrated evaluation of ASA activity, urinary sulfatide excretion and genetic tests was devised.

The associtation between aberrant right subclavian artery and trisomy 21 in a tertiary center in Turkey

OBJECTIVES

We hoped to reveal the frequency of Aberrant Right Subclavian Artery (ARSA) and to find the relationship of isolated/non-isolated ARSA with chromosomal defects and other fetal congenital heart diseases (FCHD) in a heterogeneous population.

MATERIAL AND METHODS

This was a retrospective cohort study conducted between December 2015 to September 2018. Women admitted for routine ultrasound examination or referred to our hospital for a suspected fetal anomaly were underwent detailed fetal anomaly ultrasonography scan and tested for the presence of ARSA.

RESULTS

ARSA was detected in 27 patients and an isolated finding in 13 (48%) cases. Among 13 cases with isolated ARSA, trisomy 21 was diagnosed in 1 case. In the non-isolated group (n: 14, 52%), five cases presented with trisomy 21. There was no significant difference of trisomy 21 frequency between isolated and non-isolated groups (7.6% vs 35.7%, p = 0.08). In 3 patients, FCHD was diagnosed and 2 of them had trisomy 21.

CONCLUSIONS

Our study shows that ARSA can be the only marker in trisomy 21. The examination of the subclavian artery must be a part of the fetal anomaly ultrasonography. Detecting an ARSA should increase the attentiveness of the sonographer to investigate for the other markers of trisomy 21. In the existence of other findings, invasive diagnostic procedures should be offered to the patients, whereas in cases that arsa is the only finding, other risk factors should be investigated to offer karyotyping or cell-free DNA analysis.

Genetic analysis of arylsulfatase A (ARSA) in Chinese patients with Parkinson's disease

Recently, the arylsulfatase A (ARSA) variant c.899 T > C (p.L300S) was identified to be segregated with Parkinson's disease (PD) in one family of Japanese descent. And the variant c.1055A > G (p.N352S) of ARSA was reported as a risk reduction factor for PD in a Japanese population. To further investigate the relationship between ARSA and PD, we screened these two loci of the ARSA gene in 407 sporadic PD patients and 471 healthy controls from a Chinese Han population. However, we did not detect the ARSA p.L300S variant in either PD patients or healthy controls. Moreover, in case-control association analysis, the p.N325S variant showed no significant association with PD. Therefore, these results suggested that these ARSA variants may not be common genetic factors for sporadic PD in Chinese Han population.

Reciprocal surface expression of arylsulfatase A and ubiquitin in normal and defective mammalian spermatozoa

Defective mammalian spermatozoa are marked on their surface by proteolytic chaperone ubiquitin. To identify potential ubiquitinated substrates in the defective spermatozoa, we resolved bull sperm protein extracts on a two-dimensional gel and isolated a 64-65-kDa spot (p64) corresponding to one of the major ubiquitin-immunoreactive bands observed in the one-dimensional Western blots. Immune serum raised against this protein recognized a prominent, possibly glycosylated band/spot in the range of 55-68 kDa, consistent with the original spot used for immunization. Internal sequences obtained by Edman degradation of this spot matched the sequence of arylsulfatase A (ARSA), the sperm acrosomal enzyme thought to be important for fertility. By immunofluorescence, a prominent signal was detected on the acrosomal surface (boar and bull) and on the sperm tail principal piece (bull). A second immune serum raised against a synthetic peptide corresponding to an immunogenic internal sequence (GTGKSPRRTL) of the porcine ARSA also labeled sperm acrosome and principal piece. Both sera showed diminished immunoreactivity in the defective bull spermatozoa co-labeled with an anti-ubiquitin antibody. Western blotting and image-based flow cytometry (IBFC) confirmed a reduced ARSA immunoreactivity in the immotile sperm fraction rich in ubiquitinated spermatozoa. Larger than expected ARSA-immunoreactive bands were found in sperm protein extracts immunoprecipitated with anti-ubiquitin antibodies and affinity purified with matrix-bound, recombinant ubiquitin-binding UBA domain. These bands did not show the typical pattern of ARSA glycosylation but overlapped with bands preferentially binding the Lens culinaris agglutinin (LCA) lectin. By both epifluorescence microscopy and IBFC, the LCA binding was increased in the ubiquitinated spermatozoa with diminished ARSA immunoreactivity. ARSA was also found in the epididymal fluid suggesting that in addition to intrinsic ARSA expression in the testis, epididymal spermatozoa take up ARSA on their surface during the epididymal passage. We conclude that sperm surface ARSA is one of the ubiquitinated sperm surface glycoproteins in defective bull spermatozoa. Defective sperm surface thus differs from normal sperm surface by increased ubiquitination, reduced ARSA binding, and altered glycosylation.

Three novel variants in the arylsulfatase A (ARSA) gene in patients with metachromatic leukodystrophy (MLD)

OBJECTIVE

To describe the genetic variants in the ARSA gene in Sri Lankan patients with metachromatic leukodystrophy (MLD). As the variant profile of MLD in the Sri Lankan population is currently unknown.

RESULTS

Twenty patients from eighteen Sri Lankan families were screened for ARSA gene mutations. We found 13 different genetic variants of these three were novel. The three novel variants were p.Asp281Asn, p.Asp283Asn, p.Ala344Asp. Seven patients out of 20 were also positive for the pseudodeficiency (PD) allele c.1049A>G (p.Asn350Ser). This is the first report to describe the molecular genetic variants of Sri Lankan patients with MLD.

In Silico Analysis of Missense Mutations as a First Step in Functional Studies: Examples from Two Sphingolipidoses

In order to delineate a better approach to functional studies, we have selected 23 missense mutations distributed in different domains of two lysosomal enzymes, to be studied by in silico analysis. In silico analysis of mutations relies on computational modeling to predict their effects. Various computational platforms are currently available to check the probable causality of mutations encountered in patients at the protein and at the RNA levels. In this work we used four different platforms freely available online (Protein Variation Effect Analyzer- PROVEAN, PolyPhen-2, Swiss-model Expert Protein Analysis System—ExPASy, and SNAP2) to check amino acid substitutions and their effect at the protein level. The existence of functional studies, regarding the amino acid substitutions, led to the selection of the distinct protein mutants. Functional data were used to compare the results obtained with different bioinformatics tools. With the advent of next-generation sequencing, it is not feasible to carry out functional tests in all the variants detected. In silico analysis seems to be useful for the delineation of which mutants are worth studying through functional studies. Therefore, prediction of the mutation impact at the protein level, applying computational analysis, confers the means to rapidly provide a prognosis value to genotyping results, making it potentially valuable for patient care as well as research purposes. The present work points to the need to carry out functional studies in mutations that might look neutral. Moreover, it should be noted that single nucleotide polymorphisms (SNPs), occurring in coding and non-coding regions, may lead to RNA alterations and should be systematically verified. Functional studies can gain from a preliminary multi-step approach, such as the one proposed here.

Electrophilic aldehyde products of lipid peroxidation selectively adduct to heat shock protein 90 and arylsulfatase A in stallion spermatozoa

Oxidative stress is a major determinant of mammalian sperm function stimulating lipid peroxidation cascades that culminate in the generation of potentially cytotoxic aldehydes. The aim of this study was to assess the impact of such aldehydes on the functionality of stallion spermatozoa. The impact of exposure to exogenous acrolein (ACR) and 4-hydroxynonenal (4HNE) was manifested in a highly significant dose- and time-dependent increase in mitochondrial reactive oxygen species (ROS), total cellular ROS, a decrease in sperm motility, and a time-dependent increase in lipid peroxidation. Notably, low doses of ACR and 4HNE also caused a significant decrease in zona binding. In contrast, exogenous malondialdehyde, a commonly used marker of oxidative stress, had little impact on the various sperm parameters assessed. In accounting for the negative physiological impact of ACR and 4HNE, it was noted that both aldehydes readily adducted to sperm proteins located predominantly within the head, proximal centriole, and tail. The detoxifying activity of mitochondrial aldehyde dehydrogenase 2 appeared responsible for a lack of adduction in the midpiece; however, this activity was overwhelmed by 24 h of electrophilic aldehyde exposure. Sequencing of the dominant proteins targeted for ACR and 4HNE covalent modification identified heat shock protein 90 alpha (cytosolic) class A member 1 and arylsulfatase A, respectively. These collective findings may prove useful in the identification of diagnostic biomarkers of stallion fertility and resolving the mechanistic basis of sperm dysfunction in this species.

Chromosomal microarray analysis in fetuses with aberrant right subclavian artery

OBJECTIVE

To evaluate the association between aberrant right subclavian artery (ARSA), with or without additional risk factors for aneuploidy or ultrasound abnormality, and results of chromosomal microarray analysis (CMA).

METHODS

This was a multicenter study of fetuses diagnosed with ARSA that underwent genetic analysis by CMA, all samples being analyzed in the same laboratory. Clinical investigation included nuchal translucency measurement, first- and second-trimester maternal serum screening, early and late second-trimester fetal anatomy scans and fetal echocardiography. Comparative genomic hybridization microarray analysis or single-nucleotide polymorphism array technology was used for CMA of DNA samples obtained from amniotic fluid.

RESULTS

CMA results were available for 63 fetuses with ARSA. In 36 fetuses, ARSA was an isolated finding, and no pathogenic variant was found. Additional ultrasound findings and/or risk factors for aneuploidy were present in 27 fetuses, five of which had pathogenic CMA results. Of these five, trisomy 21 was detected in a fetus with echogenic intracardiac focus (EIF), 22q11 deletion was detected in a fetus with EIF and an increased risk of trisomy 21 of 1:230 from maternal serum screening, 22q11 duplication was detected in a fetus with hypoplastic right kidney and choroid plexus cyst and 22q11 deletion was detected in a fetus with right aortic arch and clubfoot. The fifth fetus had increased nuchal translucency thickness (4 mm) and a ventricular septal defect, and CMA identified both 22q11 deletion and 1q21 duplication.

CONCLUSIONS

In fetuses with isolated ARSA, an invasive procedure for CMA is not indicated. However, CMA is recommended when additional ultrasound abnormalities or risk factors for aneuploidy are observed. The chromosomal findings in four of the five cases with an abnormal CMA result in our study would not have been detected by standard fetal chromosomal testing. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Critical issues for the proper diagnosis of Metachromatic Leukodystrophy

Metachromatic Leukodystrophy is a lysosomal storage disorder caused by Arylsulfatase A deficiency. Diagnosis is usually performed by measurement of enzymatic activity and/or characterization of the gene mutations. Here we describe a family case in which the determination of enzyme activity alone did not allow diagnosis of the pre-symptomatic sibling of the index case. Only combination of gene sequencing with thorough biochemical analysis allowed the correct diagnosis of the sibling, who was promptly directed to treatment.

Sixteen novel mutations in the arylsulfatase A gene causing metachromatic leukodystrophy

Metachromatic leukodystrophy (MLD) is a lysosomal storage disorder caused mainly by mutations in the arylsulfatase A (ARSA) gene. In this manuscript we report sixteen novel mutations identified in the ARSA gene of fifteen unrelated patients affected with MLD. Of these 16 mutations nine were missense mutations (p.L11Q, p.S44P, p.L81P, p.R84L, p.V177D, p.P284S, p.R288S, p.G301R, p.P425S), three were nonsense mutations (p.Q51X, p.Y149X, p.C156X), three were frame shift mutations (c.28delG, c.105C>A+106_124dup, c.189delC) and one was a splice-site mutation (c.1102-2A>G). In addition, three previously reported mutations were identified on an allelic background different from the one in the original reports. Two mutations, p.G309S and p.E312D, were identified on the background of the so-called pseudodeficiency (Pd) allele while previously they were reported alone. On the other hand, mutation p.R311X was identified in two unrelated patients not in cis with the Pd mutations, as previously reported.

Apolipoprotein E genotype and LRP1 polymorphisms in patients with different clinical types of metachromatic leukodystrophy

Metachromatic leukodystrophy (MLD) is a severe, neurodegenerative, metabolic disease which is caused by deficient activity of arylsulfatase A (ARSA). Sulfatides and other substrates of ARSA are stored in central and peripheral nervous systems, and in some other organs. Accumulated sulfatides are especially toxic to oligodendrocytes and Schwann cells leading to progressive demyelination. The kind of apolipoprotein E (apoE) isoform is of essential significance for the modulation of sulfatide quantity in the brain as apoE4 contains more sulfatides than apoE3. Taking into consideration the fact that apoE4 leads to the loss of sulfatides in CSF of Alzheimer's disease patients, we examined if apoE isoforms display any impact on clinical outcome in patients with different forms of MLD in whom sulfatides accumulate. The significant association of age at the onset of MLD symptoms with APOE ε2/ε3/ε4 and LRP1 c.766C>T polymorphisms was shown in multivariate stepwise regression analysis, in which other factors known to affect age at onset of the disease, i.e. clinical type of MLD, family connection of the patient and sex were also analyzed. As expected, the clinical type of MLD explained about 80% of the variance of the dependent variable. The impact of both polymorphisms on age of onset of the disease was considerably lower: 2.0% in the case of APOE polymorphism and 1.0% in the case of LRP1 polymorphism. Thus, the clinical outcome in MLD patients is related principally to the genotype of the ARSA gene, while the polymorphisms in the APOE and LRP1 genes are only slightly modifying factors.