Search Results (117)

Gaucher disease (GD) is an autosomal recessive disorder caused by the deficient activity of the lysosomal enzyme glucocerebrosidase (GCase). Although enzyme replacement therapy (ERT) remains the standard of care for non-neuropathic GD patients, its high cost significantly limits accessibility. To enhance production efficiency, we developed a lentiviral system encoding a codon-optimized GCase gene driven by the human elongation factor 1a (hEF1α) promoter for stable production in human cell lines. A functional lentiviral vector, LV_EF1α_GBA_Opt, was generated at a titer of 7.88 × 10⁸ LV particles/mL as determined by qPCR. Six transduction cycles were performed at a multiplicity of infection of 30–50. The transduced heterogeneous human cell population showed GCase-specific activity of 307.5 ± 53.49 nmol/mg protein/h, which represents a 3.21-fold increase compared to wild-type 293FT cells (95.58 ± 16.5 nmol/mg protein/h). Following single-cell cloning, two clones showed specific activity of 763.8 ± 135.1 and 752.0 ± 152.1 nmol/mg/h (clones 15 and 16, respectively). These results show that codon optimization, a lentiviral delivery system, and clonal selection together enable the establishment of stable human cell lines capable of producing high levels of biologically active, synthetic recombinant GCase in vitro. Further studies are warranted for the functional validation in GD patient-derived fibroblasts and animal models. Full article

The gut-brain axis (GBA) represents an operant acting in a two-direction communication system between the gastrointestinal tract and the central nervous system, mediated by the enteric nervous system (ENS), vagus nerve, immune pathways, and endocrine signaling. In recent years, evidence has highlighted the pivotal role of the gut microbiota in modulating this axis, forming the microbiota-gut-brain axis (MGBA). Our review synthesizes current knowledge on the anatomical and functional substrates of gut-brain communication, focusing on interoceptive signaling, the roles of intrinsic primary afferent neurons (IPANs) and enteroendocrine cells (EECs) and the influence of microbial metabolites, including short-chain fatty acids (SCFAs), bile acids, and indoles. These agents modulate neurotransmission, epithelial barrier function, and neuroimmune interactions. The vagus nerve serves as a primary pathway for afferent sensory signaling from the gut influenced indirectly by the ENS and microbiota. Dysbiosis has been associated with altered gut-brain signaling and implicated in the pathophysiology of disorders ranging from irritable bowel syndrome to mood disorders and neurodegeneration. Microbial modulation of host gene expression via epigenetic mechanisms, including microRNAs, adds another layer of complexity. The gut has a crucial role as an active sensory and signaling organ capable of influencing higher-order brain functions. Understanding the MGBA has significant implications for new therapeutic interventions targeting the microbiome to manage neurogastroenterological and even neuropsychiatric conditions. Full article

Heterozygous mutations in the GBA1 gene, encoding the enzyme glucocerebrosidase (GCase), are major risk factors for Parkinson’s Disease (PD). Ambroxol, a small chaperone originally used as a mucolytic agent, has been shown to cross the blood–brain barrier, enhance GCase activity, and reduce α-synuclein levels, making it a promising therapeutic candidate for disease-modifying effects in GBA1-associated PD (GBA1-PD). This study aimed to develop a method to quantify ambroxol levels in human plasma and cerebrospinal fluid (CSF) using liquid chromatography–tandem mass spectrometry (LC-MS/MS). Ambroxol was determined by online solid-phase extraction (SPE), coupled with LC-MS/MS, by gradient elution on a monolithic column. Detection employed a 3200 QTRAP tandem mass spectrometer in the positive electrospray ionization mode. Calibration curves exhibited linearity across the analyzed ranges in both plasma and CSF. The recovery rate ranged from 106.7% to 113.5% in plasma and from 99.0% to 103.0% in CSF. No significant matrix effect was observed. Intra-day and inter-day precisions were below 11.8% in both matrices, and accuracy ranged from 89.9% to 103.1% in plasma and from 96.3% to 107.8% in CSF. We evaluated and confirmed the stability of the analyte in plasma and CSF across various storage conditions. The method was successfully validated according to European Medicine Agency (EMA) guidelines and its applicability was confirmed in the context of a multicenter, randomized, double-blind, placebo-controlled, phase II study, designed to monitor the ambroxol levels in the plasma and CSF of GBA1-PD. Full article

Background/Objectives: Gaucher disease (GD) is an autosomal recessive lysosomal storage disorder caused by mutations in the GBA1 gene. Type 1 Gaucher disease is characterised by substrate accumulation in the visceral organs, which occurs in combination with acute and chronic neurodegeneration that distinguish type 2 and type 3 GD, respectively. We have previously shown the efficacy of neonatal AAV9 gene therapy for treating type 2 GD and aimed to investigate post-symptomatic administration into a model of type 1 disease. Current murine models of type 1 disease are limited in their recapitulation of early onset phenotypic manifestation and thus we aimed to create a novel model of type 1 in which to test the efficacy of adult gene therapy. Methods: The novel AAV-GD1 model was created through intracerebroventricular injection of AAV9 containing the human GBA1 gene under control of the neuron-specific synapsin promoter (AAV9.hSynI.hGBA1) to the pre-existing acute K14-lnl/lnl model of type 2 GD. Administration of AAV9.hSynI.hGBA1 aimed to restore glucocerebrosidase expression in the brain and extend the lifespan beyond 14 days, allowing the visceral pathology to develop further. The organ pathology was characterised by immunohistochemistry at various time points. Once visceral disease was confirmed, an intravenous injection of AAV9 containing a ubiquitously active CAG promoter driving hGBA1 (AAV9.CAG.hGBA1) was administered to post-symptomatic mice. Animals were aged for 2 and 4 months post-treatment with AAV9.CAG.hGBA1, and immunohistochemistry and enzymatic activity were assessed to investigate therapeutic efficacy. Results: The AAV-GD1 model displayed visceral pathology in the spleen, lung, and liver from 2 months of age. This allowed us to validate the efficacy of adult gene therapy; intravenous administration of AAV9.CAG.hGBA1 transiently ameliorated the lung pathology and rescued the spleen pathology up to 4 months post-administration. Conclusions: The creation of the novel AAV-GD1 model with more aggressive visceral pathology presents a unique opportunity for investigation of new therapies to treat type 1 GD. AAV9.CAG.hGBA1 represents a potential therapeutic option for all forms of Gaucher disease. Full article

Variants in the GBA1 gene, encoding the lysosomal enzyme glucosylceramidase beta 1 (GCase), are linked to Parkinson’s disease (PD) and Gaucher disease (GD). Heterozygous variants increase PD risk, while homozygous variants lead to GD, a lysosomal storage disorder. Some GBA1 variants impair GCase maturation in the endoplasmic reticulum, blocking lysosomal transport and causing glucosylceramide accumulation, which disrupts lysosomal function. This study explores therapeutic strategies to address these dysfunctions. Using Site-directed Enzyme Enhancement Therapy (SEE-Tx^®), two structurally targeted allosteric regulators (STARs), GT-02287 and GT-02329, were developed and tested in GD patient-derived fibroblasts with relevant GCase variants. Treatment with GT-02287 and GT-02329 improved the folding of mutant GCase, protected the GCase_Leu444Pro variant from degradation, and facilitated the delivery of active GCase to lysosomes. This enhanced lysosomal function and reduced cellular stress. These findings validate the STARs’ mechanism of action and highlight their therapeutic potential for GCase-related disorders, including GD, PD, and Dementia with Lewy Bodies. Full article

Gaucher disease (GD) is the most common lysosomal storage disorder, with an increased prevalence among Ashkenazi Jews. It is an autosomal recessive metabolic disorder caused by pathogenic variants in the GBA1 gene. In this study, we present the case of a 35-year-old patient who initially underwent comprehensive non-invasive prenatal testing (NIPT), which included monogenic disorder screening. The result indicated a very high risk for GD in the fetus. Subsequently, the patient opted for a confirmatory prenatal diagnostic test—prenatal Whole-Exome Sequencing (WES). The results ruled out the diagnosis of GD in the fetus and excluded other genetic disorders included in the panel. This case highlights the importance of confirmatory prenatal testing after a high-risk NIPT and underscores the value of a comprehensive approach, such as WES, in prenatal genetic diagnostics. Full article

Gaucher disease is an autosomal recessive disorder caused by dysfunction of the enzyme glucocerebrosidase. The enzyme deficiency is mainly due to mutations in the GBA1 gene, and it is responsible for the accumulation of glucosylceramide within the lysosomes of monocyte macrophage-derived cells; causing the associated symptomatology. In this paper, we describe six new mutations identified in the GBA1 gene, which, in combination with other mutations already documented, lead to absent or reduced glucocerebrosidase activity, resulting in pathological accumulation of the specific substrate and the clinical manifestations associated with Gaucher disease. We have identified three mutations (c.1578_1581dup, c.1308dup, and Y492X) that determine the formation of a premature stop codon in the translation process and three missense mutations (C342F, M280L, and Q247R) that lead to amino acid changes in proteins, resulting in decreased glucocerebrosidase activity. These mutations were never observed in our group of healthy control subjects > 1500 individuals. The patients examined had several clinical manifestations, which included hepatosplenomegaly and bone and hematologic involvement; considering the absence of enzyme activity, this suggests that the new mutations described here are associated with type I Gaucher disease. The identification of new mutations in patients with symptoms referable to Gaucher disease increases the molecular knowledge related to the GBA1 gene and offers to clinicians significant support for the accurate diagnosis of the pathology. Full article

Background: Parkinson’s disease (PD) is a genetically complex neurodegenerative disorder. Up to 15% of cases are considered monogenic. However, research on monogenic PD has largely focused on populations of European ancestry, leaving gaps in our understanding of genetic variability in other populations. This study addresses this gap by analysing the allele frequencies of pathogenic and likely pathogenic variants in known monogenic PD genes across eight global populations, using data from the gnomAD database. Methods: We compiled a list of 27 genes associated with Mendelian PD from the Online Mendelian Inheritance in Man (OMIM) database, and identified pathogenic and likely pathogenic variants using ClinVar. We then performed pairwise comparisons of allele frequencies across populations included in the gnomAD database. Variants with significant frequency differences were further assessed using in silico pathogenicity predictions. Results: We identified 81 variants across 17 genes with statistically significant allele frequency differences between at least two populations. Variants in GBA1 were the most prevalent among monogenic PD-related genes, followed by PLA2G6, ATP13A2, VPS13C, and PRKN. GBA1 exhibited the greatest variability in allele frequencies, particularly the NM_000157.4:c.1226A>G (p.Asn409Ser) variant. Additionally, we observed significant population-specific differences in PD-related variants, such as the NM_032409.3:c.1040T>C (p.Leu347Pro) variant in PINK1, which was most prevalent in East Asian populations. Conclusions: Our findings reveal substantial population-specific differences in the allele frequencies of pathogenic variants linked to monogenic PD, emphasising the need for broader genetic studies beyond European populations. These insights have important implications for PD research, genetic screening, and understanding the pathogenesis of PD in diverse populations. Full article

Sidransky syndrome represents a distinct variant of Parkinson’s disease (PD) that is linked to pathogenic variants in the glucocerebrosidase (GBA1) gene. This disorder exhibits an earlier onset, a more severe course, and a higher dementia prevalence compared to idiopathic PD. While the pathogenesis remains debated between loss-of-function and gain-of-function mechanisms, targeted therapies are emerging. Pharmacological chaperones (PCs), like high-dose Ambroxol, aim to mitigate enzyme misfolding—a primary driver of this disorder—rather than addressing metabolic deficiencies seen in Gaucher disease. Despite failed trials of substrate reduction therapies, current clinical trials with Ambroxol and other PCs highlight promising avenues for disease modification. This commentary advocates for increased awareness of Sidransky syndrome to advance diagnostic strategies, promote genetic testing, and refine targeted treatments, with the potential to transform care for GBA1-related PD and prodromal stages of the disease. Full article

We introduce an innovative, non-invasive prenatal screening approach for detecting fetal monogenic alterations and copy number variations (CNVs) from maternal blood. Method: Circulating free DNA (cfDNA) was extracted from maternal peripheral blood and processed using the VeriSeq NIPT Solution (Illumina, San Diego, CA, USA), with shallow whole-genome sequencing (sWGS) performed on a NextSeq550Dx (Illumina). A customized gene panel and bioinformatics tool, named the “VERA Revolution”, were developed to detect variants and CNVs in cfDNA samples. Results were compared with genomic DNA (gDNA) extracted from fetal samples, including amniotic fluid and chorionic villus sampling and buccal swabs. Results: The study included pregnant women with gestational ages from 10 + 3 to 15 + 2 weeks (mean: 12.1 weeks). The fetal fraction (FF), a crucial measure of cfDNA test reliability, ranged from 5% to 20%, ensuring adequate DNA amount for analysis. Among 36 families tested, 14 showed a wild-type genotype. Identified variants included two deletions (22q11.2, and 4p16.3), two duplications (16p13 and 5p15), and eighteen single-nucleotide variants (one in CFTR, three in GJB2, three in PAH, one in RIT1, one in DHCR7, one in TCOF1, one in ABCA4, one in MYBPC3, one in MCCC2, two in GBA1 and three in PTPN11). Significant concordance was found between our panel results and prenatal/postnatal genetic profiles. Conclusions: The “VERA Revolution” test highlights advancements in prenatal genomic screening, offering potential improvements in prenatal care. Full article

Introduction: The differential diagnosis of splenomegaly is a complex process that encompasses a wide variety of diseases. Moreover, it is not always standardized and lacks a definitive consensus on which tests should be performed and in what order. Gaucher disease (GD) and acid sphingomyelinase deficiency (ASMD) are lysosomal diseases (LD) that present with splenomegaly, the diagnosis of which requires a high index of suspicion and specific biochemical and genetic techniques. The aim of the project for the education and diagnosis of Gaucher disease and acid sphingomyelinase deficiency (PREDIGA) was to conduct educational training alongside an observational, multicenter, ambispective, cross-sectional, single-cohort study among patients having an enlarged spleen or undergone splenectomy to further assess these subjects to exclude two lysosomal diseases, namely GD and ASMD. Methods: Using dried blood spot (DBS) testing, we identified patients with abnormally low values of the enzymes glucocerebrosidase and acid sphingomyelinase, who then underwent sequencing of the GBA1 and SPMD1 genes, respectively. The study involved 34 hospitals and 52 medical specialists. Results: We identified 220 patients (208 adults and 12 children under 18 years) with cryptogenic splenomegaly or who had undergone splenectomy (12 patients) without having reached a diagnosis. The median age was 11 years (interquartile range [IQR] 3–16) in the pediatric population and 51 years (IQR 38–65) in the adult population. Lower-than-normal enzyme values were detected in 19 DBSs, confirming eight positive cases, which corresponded to six patients with GD and two with ASMD. The rest of the DBSs with low enzyme activity were not genetically confirmed (58%). We determined that lysosomal diseases accounted for 3.6% of cryptogenic splenomegaly/splenectomy cases in our setting: 2.7% were GD and 0.9% ASMD, in a ratio of 1 ASMD patient to every 3 GD patients. Lyso-GL1 values in patients with GD were elevated in all but one individual, corresponding to a child diagnosed at 4 months old. The variants detected in the GBA1 gene were consistent with the most frequent variants found in Spain. Discussion/Conclusion: The development and implementation of this protocol for the education and diagnosis of cryptogenic splenomegaly/splenectomy, even in asymptomatic patients, constitutes a comprehensive, simple, rapid, and effective screening method for the diagnosis of GD and ASMD. Full article

Background: Gaucher disease (GD) is a rare autosomal recessive lysosomal storage disorder caused by mutations in the GBA1 gene, leading to deficient β-glucocerebrosidase activity. This results in the accumulation of glucocerebroside in macrophages, primarily affecting the liver, spleen, bone marrow, and bones. Understanding the clinical outcomes and genetic mutation profiles in specific populations, such as Turkish patients, is essential for optimized disease management and personalized therapy and preventing morbidity and mortality. Method: This retrospective study analyzed data from 29 Turkish patients with previously diagnosed type 1 GD at a single center between September and December 2023. Genetic analyses were performed to identify GBA1 mutations using next-generation sequencing. Genetic mutations were the primary criterion for diagnosing GD. Clinical features, treatment responses, and outcomes were evaluated. Clinical parameters included hematological findings, organomegaly, and bone involvement. Data were analyzed to identify potential correlations between genetic mutations and clinical manifestations. Results: This study included 14 male and 15 female patients, with a mean diagnosis age of 22.1 years. A significant family history was observed in 93% of cases, and 52% had consanguineous parents. Epistaxis (72%) was the most common pre-diagnosis symptom. Most patients received enzyme replacement therapy with 60 units/kg. Treatment led to significant improvements, including increased hemoglobin (21.1%), higher platelet count (86.1%), and reduced organomegaly (liver (10.02%), spleen (25.22%)). Genetic analysis identified seven mutations, with c.1226A>G (p.N409S) being the most frequent. Conclusions: This study highlights the spectrum of clinical outcomes and genetic mutations in Turkish patients with GD, emphasizing the variability in disease severity based on genotype. GD should be considered for patients with unexplained nosebleeds, hepatosplenomegaly, bone pain, weakness, or siblings or other family members with similar symptoms. The genetic analysis revealed considerable heterogeneity among patients, which indicates the necessity of observing this in the development of personalized treatment strategies. Future studies with larger cohorts and long-term follow-up are needed to further elucidate genotype–phenotype correlations in this population. Full article

Parkinson’s Disease (PD) is the most frequent movement disorder and is second only to Alzheimer’s Disease as the most frequent neurodegenerative pathology. Early onset Parkinson’s disease (EOPD) is less common and may be characterized by genetic predisposition. NGS testing might be useful in the diagnostic assessment of these patients. A panel of eight genes (SNCA, PRKN, PINK1, DJ1, LRRK2, FBXO7, GBA1 and HFE) was validated and used as a diagnostic tool. A total of 38 in sequence EOPD patients of the Parkinson’s Disease Unit of our Hospital Institution were tested. In addition, the number of the hexanucleotide repeats of the C9ORF72 gene and the frequency of main HFE mutations were evaluated. Six patients were carriers of likely pathogenic mutations in heterozygosity in the analyzed genes, one of them presented mutations in association and another had a complex genetic background. Their clinical symptoms were correlated with their genotypes. In the cohort of patients, only the p.Cys282Tyr of HFE was significantly decreased in the dominant model and allele contrast comparison. Only one patient with one allele of C9ORF72 containing 10 repeats was identified and clinically described. The clinical signs of sporadic and monogenic PD are often very similar; for this reason, it is fundamental to correlate genotypes and phenotypes, as we tried to describe here, to better classify PD patients with the aim to deepen our knowledge in the molecular mechanisms involved and collaborate in reaching a personalized management and treatment. Full article

Preimplantation genetic testing (PGT) is practiced worldwide, allowing the prevention of the transmission and expression of various genetic conditions. Socio-ethical considerations of justified applications for PGT are part of an ongoing debate. Pathogenic variants in the glucocerebrosidase (GBA1) gene, causing Gaucher disease (GD), have emerged as a risk factor for Parkinson’s disease (PD) in both patients and carriers. Genotype–phenotype correlations exist between different GBA1 pathogenic variants and the risk to develop PD: mild pathogenic variants increase the risk of developing PD by ~3-fold, while severe pathogenic variants increase this risk by ~15-fold, occurring at a younger age. A woman with GD, a compound heterozygote of N370S (now commonly described as c.1226A>G (N409S)—mild pathogenic variant) and 84insG (severe pathogenic variant), had PGT consulting before planned in vitro-fertilization. Her mother, an 84insG carrier, had early-onset PD. GBA1 sequencing of her spouse was negative. We discussed the selection for N370S carrier embryos to reduce PD risk. This case report demonstrates the expansion of PGT for late-onset conditions. These novel indications will increase the number of subjects who would be candidates for PGT. The medical and bioethical considerations of these cases should be acknowledged by the professional community and discussed with couples during genetic counseling. Full article

Parkinson’s disease (PD) is the second most common neurodegenerative disease in the world. Currently, PD is incurable, and the diagnosis of PD mainly relies on clinical manifestations. The central pathological event in PD is the abnormal aggregation and deposition of misfolded α-synuclein (α-Syn) protein aggregates in the Lewy body (LB) in affected brain areas. Behaving as a prion-like seeding, the misfolded α-syn protein can induce and facilitate the aggregation of native unfolded α-Syn protein to aggravate α-Syn protein aggregation, leading to PD progression. Recently, in a blood-based α-Syn seeding amplification assay (SAA), Kluge et al. identified pathological α-Syn seeding activity in PD patients with Parkin (PRKN) gene variants. Additionally, pathological α-syn seeding activity was also identified in sporadic PD and PD patients with Leucine-rich repeat kinase 2 (LRRK2) or glucocerebrosidase (GBA) gene variants. Principally, the α-Syn SAA can be used to detect pathological α-Syn seeding activity, which will significantly enhance PD diagnosis, progression monitoring, prognosis prediction, and anti-PD therapy. The significance and future strategies of α-Syn SAA protocol are highlighted and proposed, whereas challenges and limitations of the assay are discussed. Full article