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Molecular Genetics and Metabolism May 2021MPS disorders are associated with a wide spectrum of neurocognitive effects, from mild problems with attention and executive functions to progressive and degenerative... (Review)
Review
MPS disorders are associated with a wide spectrum of neurocognitive effects, from mild problems with attention and executive functions to progressive and degenerative neuronopathic disease. Studies of the natural history of neurocognition are necessary to determine the profile of abnormality and the rates of change, which are crucial to select endpoints for clinical trials of brain treatments and to make clinical recommendations for interventions to improve patients' quality of life. The goal of this paper is to review neurocognitive natural history studies to determine the current state of knowledge and assist in directing future research in all MPS disorders. There are seven different types of MPS diseases, each resulting from a specific enzyme deficiency and each having a separate natural history. MPS IX, will not be discussed as there are only 4 cases reported in the literature without cognitive abnormality. For MPS IH, hematopoietic cell transplant (HCT) is standard of care and many studies have documented the relationship between age at treatment and neurocognitive outcome, and to a lesser extent, neurocognitive status at baseline. However, the mortality and morbidity associated with the transplant process and residual long-term problems after transplant, have led to renewed efforts to find better treatments. Rather than natural history, new trials will likely need to use the developmental trajectories of the patients with HCT as a comparators. The literature has extensive data regarding developmental trajectories post-HCT. For attenuated MPS I, significant neurocognitive deficits have been documented, but more longitudinal data are needed in order to support a treatment directed at their attention and executive function abnormalities. The neuronopathic form of MPS II has been a challenge due to the variability of the trajectory of the disease with differences in timing of slowing of development and decline. Finding predictors of the course of the disease has only been partially successful, using mutation type and family history. Because of lack of systematic data and clinical trials that precede a thorough understanding of the disease, there is need for a major effort to gather natural history data on the entire spectrum of MPS II. Even in the attenuated disease, attention and executive function abnormalities need documentation. Lengthy detailed longitudinal studies are needed to encompass the wide variability in MPS II. In MPS IIIA, the existence of three good natural history studies allowed a quasi-meta-analysis. In patients with a rapid form of the disease, neurocognitive development slowed up until 42 to 47 months, halted up to about 54 months, then declined rapidly thereafter, with a leveling off at an extremely low age equivalent score below 22 months starting at about chronological age of 6. Those with slower or attenuated forms have been more variable and difficult to characterize. Because of the plethora of studies in IIIA, it has been recommended that data be combined from natural history studies to minimize the burden on parents and patients. Sufficient data exists to understand the natural history of cognition in MPS IIIA. MPS IIIB is quite similar to IIIA, but more attenuated patients in that phenotype have been reported. MPS IIIC and D, because they are so rare, have little documentation of natural history despite the prospects of treatments. MPS IV and VI are the least well documented of the MPS disorders with respect to their neurocognitive natural history. Because, like attenuated MPS I and II, they do not show progression of neurocognitive abnormality and most patients function in the range of normality, their behavioral, attentional, and executive function abnormalities have been ignored to the detriment of their quality of life. A peripheral treatment for MPS VII, extremely rare even among MPS types, has recently been approved with a post-approval monitoring system to provide neurocognitive natural history data in the future. More natural history studies in the MPS forms with milder cognitive deficits (MPS I, II, IV, and VI) are recommended with the goal of improving these patients' quality of life with and without new brain treatments, beyond the benefits of available peripheral enzyme replacement therapy. Recommendations are offered at-a-glance with respect to what areas most urgently need attention to clarify neurocognitive function in all MPS types.
Topics: Brain; Cognition; Enzyme Replacement Therapy; Hematopoietic Stem Cell Transplantation; Humans; Mucopolysaccharidosis I; Mucopolysaccharidosis II; Mucopolysaccharidosis III; Neurocognitive Disorders; Quality of Life
PubMed: 33741271
DOI: 10.1016/j.ymgme.2021.03.002 -
Molecular Genetics and Metabolism... Sep 2021Vestronidase alfa is an enzyme replacement therapy for mucopolysaccharidosis VII (MPS VII). In this open-label, phase 1/2 study, three subjects with MPS VII received...
Vestronidase alfa is an enzyme replacement therapy for mucopolysaccharidosis VII (MPS VII). In this open-label, phase 1/2 study, three subjects with MPS VII received intravenous vestronidase alfa administered every other week (QOW) for 14 weeks (2 mg/kg), followed by 24-week forced-dose titration (1, 4, and 2 mg/kg QOW; 8 weeks each), 36-week continuation (2 mg/kg), and long-term extension (4 mg/kg). Vestronidase alfa was well tolerated and led to dose-responsive, sustained reductions in urinary glycosaminoglycan excretion.
PubMed: 34136357
DOI: 10.1016/j.ymgmr.2021.100774 -
JIMD Reports 2018Mucopolysaccharidosis type VII (MPS VII) is caused by β-glucuronidase deficiency, resulting in lysosomal accumulation of glycosaminoglycans (GAGs) and multisystemic...
Mucopolysaccharidosis type VII (MPS VII) is caused by β-glucuronidase deficiency, resulting in lysosomal accumulation of glycosaminoglycans (GAGs) and multisystemic disease. We present cardiovascular gross and histopathology findings from a 11-year-old MPS VII male, who expired after developing ventricular fibrillation following anesthesia induction. Gross anatomic observations were made at autopsy; postmortem formalin-fixed paraffin-embedded samples of the carotid artery, aorta, myocardium, and valves were sectioned and stained with hematoxylin-eosin, Verhoeff-Van Gieson, CD68, and trichrome stains. Gross heart findings include an enlarged, dilated heart, mitral valve prolapse with thick, shortened chordae tendinae, and thickened aortic valve cusps. The aorta contained raised intimal plaques mimicking conventional atherosclerosis. Cardiac myocytes included hypertrophic nuclei, subendocardial fibrosis, and increased interfascicular collagen. Coronary lumens were 40-70% stenosed by fibrointimal hyperplasia containing storage material-laden cells, CD68 macrophages, and fragmented elastin laminae. Similar findings were visualized in aortic intimal plaques. We confirm that arterial plaques, elastin fragmentation, and activated CD68 macrophage infiltration occur in human MPS VII, consistent with previously observed findings in murine and canine MPS VII. We also confirm ultrasonographically observed carotid intimal-medial thickening is an in vivo correlate of histopathologic vascular fibrointimal hyperplasia. MPS VII patients should be regularly monitored for cardiac disease, with methods such as Holter monitors and stress testing; MPS VII-directed treatments should effectively address cardiovascular disease.
PubMed: 28702876
DOI: 10.1007/8904_2017_43 -
International Journal of Molecular... Nov 2016The prevalence of aortic root dilatation (ARD) in mucopolysaccharidosis (MPS) is not well documented. We investigated aortic root measurements in 34 MPS patients at the...
The prevalence of aortic root dilatation (ARD) in mucopolysaccharidosis (MPS) is not well documented. We investigated aortic root measurements in 34 MPS patients at the Children's Hospital of Orange County (CHOC). The diagnosis, treatment status, age, gender, height, weight and aortic root parameters (aortic valve annulus (AVA), sinuses of Valsalva (SoV), and sinotubular junction (STJ)) were extracted by retrospective chart review and echocardiographic measurements. Descriptive statistics, ANOVA, and paired post-hoc -tests were used to summarize the aortic dimensions. Exact binomial 95% confidence intervals (CIs) were constructed for ARD, defined as a score greater than 2 at the SoV. The patient age ranged from 3.4-25.9 years (mean 13.3 ± 6.1), the height from 0.87-1.62 meters (mean 1.24 ± 0.21), and the weight from 14.1-84.5 kg (mean 34.4 ± 18.0). The prevalence of dilation at the AVA was 41% (14/34; 95% CI: 25%-59%); at the SoV was 35% (12/34; 95% CI: 20%-54%); and at the STJ was 30% (9/30; 95% CI: 15%-49%). The highest prevalence of ARD was in MPS IVa (87.5%). There was no significant difference between mean z-scores of MPS patients who received treatment with hematopoietic stem cell transplantation (HSCT) or enzyme replacement therapy (ERT) vs. untreated MPS patients at the AVA ( = 1.9 ± 2.5 vs. = 1.5 ± 2.4; = 0.62), SoV ( = 1.2 ± 1.6 vs. = 1.3 ± 2.2; = 0.79), or STJ ( = 1.0 ± 1.8 vs. = 1.2 ± 1.6; = 0.83). The prevalence of ARD was 35% in our cohort of MPS I-VII patients. Thus, we recommend screening for ARD on a routine basis in this patient population.
Topics: Adolescent; Adult; Aorta; Aortic Diseases; Child; Dilatation, Pathologic; Female; Humans; Male; Mucopolysaccharidosis I; Mucopolysaccharidosis II; Mucopolysaccharidosis III; Mucopolysaccharidosis IV; Mucopolysaccharidosis VI; Mucopolysaccharidosis VII; Retrospective Studies; Young Adult
PubMed: 27916847
DOI: 10.3390/ijms17122004 -
The British Journal of Radiology Jan 2014Lysosomal storage diseases (LSDs) are a large group of genetic metabolic disorders that result in the accumulation of abnormal material, such as mucopolysaccharides,... (Review)
Review
Lysosomal storage diseases (LSDs) are a large group of genetic metabolic disorders that result in the accumulation of abnormal material, such as mucopolysaccharides, glycoproteins, amino acids and lipids, within cells. Since many LSDs manifest during infancy or early childhood, with potentially devastating consequences if left untreated, timely identification is imperative to prevent irreversible damage and early death. In this review, the key imaging features of the non-lipid or extralipid LSDs are examined and correlated with salient clinical manifestations and genetic information. Disorders are stratified based on the type of excess material causing tissue or organ dysfunction, with descriptions of the mucopolysaccharidoses, mucolipidoses, alpha-mannosidosis, glycogen storage disorder II and cystinosis. In addition, similarities and differences in radiological findings between each of these LSDs are highlighted to facilitate further recognition. Given the rare and extensive nature of the LSDs, mastery of their multiple clinical and radiological traits may seem challenging. However, an understanding of the distinguishing imaging characteristics of LSDs and their clinical correlates may allow radiologists to play a key role in the early diagnosis of these progressive and potentially fatal disorders.
Topics: Diagnosis, Differential; Glucuronidase; Humans; Lyases; Lysosomal Storage Diseases; Metabolism, Inborn Errors; Mucopolysaccharidosis I; Mucopolysaccharidosis II; Mucopolysaccharidosis III; Mucopolysaccharidosis IV; Mucopolysaccharidosis VI; Mucopolysaccharidosis VII
PubMed: 24234586
DOI: 10.1259/bjr.20130467 -
Neuromuscular Disorders : NMD Jul 1997Mucopolysaccharidosis type VII (MPS VII) is caused by a deficiency in the lysosomal enzyme beta-glucuronidase resulting in the accumulation of undegraded... (Review)
Review
Mucopolysaccharidosis type VII (MPS VII) is caused by a deficiency in the lysosomal enzyme beta-glucuronidase resulting in the accumulation of undegraded glycosaminoglycans in many tissues. A murine model of MPS VII shares many of the clinical, biochemical and histopathological features of human MPS VII and has provided an opportunity to study novel therapeutic approaches in a system with a uniform genetic background. Retroviral mediated gene therapy directed to the hematopoietic system or to artificial neo-organs resulted in low levels of enzyme in several tissues and reduced lysosomal storage in the liver and spleen. Partial correction of the disease in the eye was observed following an intravitreal injection of recombinant adenovirus. Neither retroviral nor adenoviral mediated gene transfer techniques resulted in a systemic reduction of lysosomal storage. Here we discuss several novel gene transfer approaches designed to increase the systemic levels of beta-glucuronidase in the MPS VII mouse.
Topics: Adenoviridae; Animals; Bone Marrow Transplantation; Disease Models, Animal; Genetic Therapy; Genetic Vectors; Glucuronidase; Hematopoiesis; Mice; Mucopolysaccharidosis VII; Rodent Diseases
PubMed: 9267850
DOI: 10.1016/s0960-8966(97)00061-8 -
Molecular Genetics and Metabolism Sep 2012Mucopolysaccharidosis type VII (MPS VII) is characterized by deficient β-glucuronidase (GUSB) activity, which leads to accumulation of chondroitin, heparan and dermatan...
Mucopolysaccharidosis type VII (MPS VII) is characterized by deficient β-glucuronidase (GUSB) activity, which leads to accumulation of chondroitin, heparan and dermatan sulfate glycosaminoglycans (GAGs), and multisystemic disease. MPS VII patients can develop kypho-scoliotic deformity and spinal cord compression due to disease of intervertebral disks, vertebral bodies, and associated tissues. We have previously demonstrated in MPS VII dogs that intervertebral disks degenerate, vertebral bodies have irregular surfaces, and vertebral body epiphyses have reduced calcification, but the pathophysiological mechanisms underlying these changes are unclear. We hypothesized that some of these manifestations could be due to upregulation of destructive proteases, possibly via the binding of GAGs to Toll-like receptor 4 (TLR4), as has been proposed for other tissues in MPS models. In this study, the annulus fibrosus of the intervertebral disk of 6-month-old MPS VII dogs had cathepsin B and K activities that were 117- and 2-fold normal, respectively, which were associated with elevations in mRNA levels for these cathepsins as well as TLR4. The epiphyses of MPS VII dogs had a marked elevation in mRNA for the cartilage-associated gene collagen II, consistent with a developmental delay in the conversion of the cartilage to bone in this region. The spine obtained at autopsy from a young man with MPS VII exhibited similar increased cartilage in the vertebral bodies adjacent to the end plates, disorganization of the intervertebral disks, and irregular vertebral end plate morphology. These data suggest that the pathogenesis of destructive changes in the spine in MPS VII may involve upregulation of cathepsins. Inhibition of destructive proteases, such as cathepsins, might reduce spine disease in patients with MPS VII or related disorders.
Topics: Animals; Animals, Genetically Modified; Cathepsins; Cytokines; Disease Models, Animal; Dogs; Extracellular Matrix; Female; Humans; Lumbar Vertebrae; Male; Matrix Metalloproteinases; Mucopolysaccharidosis VII; RNA, Messenger; Radiography; Spinal Diseases
PubMed: 22513347
DOI: 10.1016/j.ymgme.2012.03.014 -
Biochimica Et Biophysica Acta.... Jul 2022Mucopolysaccharidosis type VII (MPS VII) is a recessively inherited lysosomal storage disorder caused due to β-glucuronidase (β-GUS) enzyme deficiency. Prominent...
Mucopolysaccharidosis type VII (MPS VII) is a recessively inherited lysosomal storage disorder caused due to β-glucuronidase (β-GUS) enzyme deficiency. Prominent clinical symptoms include hydrops fetalis, musculoskeletal deformities, neurodegeneration and hepatosplenomegaly leading to premature death in most cases. Apart from these, MPS VII is also characterized as adipose storage deficiency disorder although the underlying mechanism of this lean phenotype in the patients or β-GUS-deficient mice still remains a mystery. We addressed this issue using our recently developed Drosophila model of MPS VII (the CG2135 fly), which also exhibited a significant loss of body fat. We report here that the lean phenotype of the CG2135 larvae is due to fewer number of adipocytes, smaller lipid droplets and reduced adipogenesis. Our data further revealed that there is an abnormal accumulation of autophagosomes in the CG2135 larvae due to autophagosome-lysosome fusion defect. Decreased lysosome-mediated turnover also led to attenuated mTOR activity in the CG2135 larvae. Interestingly, treatment of the CG2135 larvae with mTOR stimulators, 3BDO or glucose, led to the restoration of mTOR activity with simultaneous correction of the autophagy defect and adipose storage deficiency. Our finding thus established a hitherto unknown mechanistic link between autophagy dysfunction, mTOR downregulation and reduced adiposity in MPS VII.
Topics: Adipose Tissue; Animals; Autophagy; Drosophila; Humans; Mice; Mucopolysaccharidosis VII; TOR Serine-Threonine Kinases
PubMed: 35318126
DOI: 10.1016/j.bbadis.2022.166399 -
Orphanet Journal of Rare Diseases May 2024Mucopolysaccharidosis VII (MPS VII) is an ultra-rare, autosomal recessive, debilitating, progressive lysosomal storage disease caused by reduced activity of...
Disease characteristics, effectiveness, and safety of vestronidase alfa for the treatment of patients with mucopolysaccharidosis VII in a novel, longitudinal, multicenter disease monitoring program.
BACKGROUND
Mucopolysaccharidosis VII (MPS VII) is an ultra-rare, autosomal recessive, debilitating, progressive lysosomal storage disease caused by reduced activity of β-glucuronidase (GUS) enzyme. Vestronidase alfa (recombinant human GUS) intravenous enzyme replacement therapy is an approved treatment for patients with MPS VII.
METHODS
This disease monitoring program (DMP) is an ongoing, multicenter observational study collecting standardized real-world data from patients with MPS VII (N ≈ 50 planned) treated with vestronidase alfa or any other management approach. Data are monitored and recorded in compliance with Good Clinical Practice guidelines and planned interim analyses of captured data are performed annually. Here we summarize the safety and efficacy outcomes as of 17 November 2022.
RESULTS
As of the data cutoff date, 35 patients were enrolled: 28 in the Treated Group and seven in the Untreated Group. Mean (SD) age at MPS VII diagnosis was 4.5 (4.0) years (range, 0.0 to 12.4 years), and mean (SD) age at DMP enrollment was 13.9 (11.1) years (range, 1.5 to 50.2 years). Ten patients (29%) had a history of nonimmune hydrops fetalis. In the 23 patients who initiated treatment prior to DMP enrollment, substantial changes in mean excretion from initial baseline to DMP enrollment were observed for the three urinary glycosaminoglycans (uGAGs): dermatan sulfate (DS), -84%; chondroitin sulfate (CS), -55%; heparan sulfate (HS), -42%. Also in this group, mean reduction from initial baseline to months 6, 12, and 24 were maintained for uGAG DS (-84%, -87%, -89%, respectively), CS (-70%, -71%, -76%, respectively), and HS (+ 3%, -32%, and - 41%, respectively). All adverse events (AEs) were consistent with the known vestronidase alfa safety profile. No patients discontinued vestronidase alfa. One patient died.
CONCLUSIONS
To date, the DMP has collected invaluable MPS VII disease characteristic data. The benefit-risk profile of vestronidase alfa remains unchanged and favorable for its use in the treatment of pediatric and adult patients with MPS VII. Reductions in DS and CS uGAG demonstrate effectiveness of vestronidase alfa to Month 24. Enrollment is ongoing.
Topics: Humans; Mucopolysaccharidosis VII; Glucuronidase; Male; Child, Preschool; Female; Child; Enzyme Replacement Therapy; Recombinant Proteins; Infant; Longitudinal Studies; Adolescent
PubMed: 38715031
DOI: 10.1186/s13023-024-03176-z -
Molecular Therapy : the Journal of the... Apr 2014Severe deficiency in lysosomal β-glucuronidase (β-glu) enzymatic activity results in mucopolysaccharidosis (MPS) VII, an orphan disease with symptoms often appearing...
Severe deficiency in lysosomal β-glucuronidase (β-glu) enzymatic activity results in mucopolysaccharidosis (MPS) VII, an orphan disease with symptoms often appearing in early childhood. Symptoms are variable, but many patients have multiple organ disorders including neurological defects. At the cellular level, deficiency in β-glu activity leads to abnormal accumulation of glycosaminoglycans (GAGs), and secondary accumulation of GM2 and GM3 gangliosides, which have been linked to neuroinflammation. There have been encouraging gene transfer studies in the MPS VII mouse brain, but this is the first study attempting the correction of the >200-fold larger and challenging canine MPS VII brain. Here, the efficacy of a helper-dependent (HD) canine adenovirus (CAV-2) vector harboring a human GUSB expression cassette (HD-RIGIE) in the MPS VII dog brain was tested. Vector genomes, β-glu activity, GAG content, lysosome morphology and neuropathology were analyzed and quantified. Our data demonstrated that CAV-2 vectors preferentially transduced neurons and axonal retrograde transport from the injection site to efferent regions was efficient. HD-RIGIE injections, associated with mild and transient immunosuppression, corrected neuropathology in injected and noninjected structures throughout the cerebrum. These data support the clinical evaluation of HD CAV-2 vectors to treat the neurological defects associated with MPS VII and possibly other neuropathic lysosomal storage diseases.
Topics: Animals; Brain; Disease Models, Animal; Dogs; Gene Expression Regulation, Enzymologic; Gene Transfer Techniques; Genetic Therapy; Glycosaminoglycans; Humans; Mice; Mucopolysaccharidosis VII; beta-Glucosidase
PubMed: 24343103
DOI: 10.1038/mt.2013.283