scholarly journals The Action of Recombinant Human Lysosomal α-Glucosidase (rhGAA) on Human Liver Glycogen: Pathway to Complete Degradation

2021 ◽  
Vol 1 (3) ◽  
pp. 381-402
Author(s):  
Allen K. Murray
Keyword(s):  
Pompe Disease ◽  
Liver Glycogen ◽  
Carbohydrate Composition ◽  
Short Term ◽  
Future Directions ◽  
Enzyme Replacement ◽  
Glycosylation Sites ◽  
Residual Material ◽  
Branched Chain ◽  
Carbohydrate Components

Glycogen is present in all tissues, but it is primarily stored in the liver and in muscle. As a branched chain carbohydrate, it is broken down by phosphorylase and debrancher enzymes, which are cytoplasmic. It is also degraded by a lysosomal α-glucosidase (GAA) also known as acid α-glucosidase and lysosomal acid α-glucosidase. The deficiency of GAA in patients is known as Pompe disease, and the phenotypes as infantile, juvenile and later onset forms. Pompe disease is treated by enzyme replacement therapy (ERT) with a recombinant form of rhGAA. Following ERT in Pompe mice and human patients there is residual carbohydrate material present in the cytoplasm of cells. The goal of this work is to improve ERT and attempt to identify and treat the residual cytoplasmic carbohydrate. Initial experiments were to determine if rhGAA can completely degrade glycogen. The enzyme cannot completely degrade glycogen. There is a residual glycosylated protein as well as a soluble glycosylated protein, which is a terminal degradation product of glycogen and as such serves as a biomarker for lysosomal glycogen degradation. The glycosylated protein has a very unusual carbohydrate composition for a glycosylated protein: m-inositol, s-inositol and sorbitol as the major carbohydrates, as well as mannitol, mannose, glucose and galactose. This work describes the residual material which likely contains the same protein as the soluble glycosylated protein. The biomarker is present in serum of control and Pompe patients on ERT, but it is not present in the serum of Pompe mice not on ERT. Pompe mice not on ERT have another glycosylated protein in their serum which may be a biomarker for Pompe disease. This protein has multiple glycosylation sites, each with different carbohydrate components. These glycosylated proteins as well as the complexity of glycogen structure are discussed, as well as future directions to try to improve the outcome of ERT for Pompe patients by being able to monitor the efficacy of ERT in the short term and possibly to adjust the timing and dose of enzyme infusions.

Cardiac and motor improvement with enzyme replacement therapy in a patient with infantile-onset Pompe disease

2005 ◽  
Vol 36 (02) ◽  
Author(s):  
M Smitka ◽  
M von der Hagen ◽  
A Kaindl ◽  
C Gilitzer ◽  
J Dumontier ◽  
...  
Keyword(s):  
Enzyme Replacement Therapy ◽  
Replacement Therapy ◽  
Pompe Disease ◽  
Enzyme Replacement ◽  
Motor Improvement

Short-term psychodynamic psychotherapy: a brief history

2019 ◽  
Vol 27 (6) ◽  
pp. 581-583
Author(s):  
James Baée ◽  
Neil Jeyasingam
Keyword(s):  
Psychodynamic Psychotherapy ◽  
Short Term ◽  
Future Directions ◽  
Current Climate

Objective: To discuss the development and rationale for different models of short-term psychodynamic psychotherapy. Conclusion: There are a variety of historical reasons for the current climate of short-term dynamic therapies that can help inform upon their application and future directions.

Description of a patient with infantile onset Pompe disease after 45 months of enzyme replacement therapy

2018 ◽  
Vol 123 (2) ◽  
pp. S124-S125
Author(s):  
Roberto Sandobal Pacheco ◽  
Diana Espinosa Villanueva ◽  
Adriana Alcnatara Salinas ◽  
Jorge A. Romero Ramirez ◽  
Jose Antonio Vasquez Galeana ◽  
...  
Keyword(s):  
Enzyme Replacement Therapy ◽  
Replacement Therapy ◽  
Pompe Disease ◽  
Enzyme Replacement

scholarly journals Effect of short-term fasting and glucocorticoids on KLF15 expression and branched-chain amino acids metabolism in Chinese perch

2021 ◽  
Vol 19 ◽  
pp. 100617
Author(s):  
Xin Zhu ◽  
Jiangli Hu ◽  
Jianshe Zhang ◽  
Jingjie Liu ◽  
Lingsheng Bao ◽  
...  
Keyword(s):  
Amino Acids ◽  
Branched Chain Amino Acids ◽  
Short Term ◽  
Chinese Perch ◽  
Branched Chain

scholarly journals Rare Variants in Autophagy and Non-Autophagy Genes in Late-Onset Pompe Disease: Suggestions of Their Disease-Modifying Role in Two Italian Families

2021 ◽  
Vol 22 (7) ◽  
pp. 3625
Author(s):  
Filomena Napolitano ◽  
Giorgia Bruno ◽  
Chiara Terracciano ◽  
Giuseppina Franzese ◽  
Nicole Piera Palomba ◽  
...  
Keyword(s):  
Pompe Disease ◽  
Rare Variants ◽  
Clinical Symptoms ◽  
Late Onset ◽  
Respiratory Muscles ◽  
Autosomal Recessive Disorder ◽  
Compound Heterozygous ◽  
Enzyme Replacement ◽  
Whole Exome ◽  
Clinical Pictures

Pompe disease is an autosomal recessive disorder caused by a deficiency in the enzyme acid alpha-glucosidase. The late-onset form of Pompe disease (LOPD) is characterized by a slowly progressing proximal muscle weakness, often involving respiratory muscles. In LOPD, the levels of GAA enzyme activity and the severity of the clinical pictures may be highly variable among individuals, even in those who harbour the same combination of GAA mutations. The result is an unpredictable genotype–phenotype correlation. The purpose of this study was to identify the genetic factors responsible for the progression, severity and drug response in LOPD. We report here on a detailed clinical, morphological and genetic study, including a whole exome sequencing (WES) analysis of 11 adult LOPD siblings belonging to two Italian families carrying compound heterozygous GAA mutations. We disclosed a heterogeneous pattern of myopathic impairment, associated, among others, with cardiac defects, intracranial vessels abnormality, osteoporosis, vitamin D deficiency, obesity and adverse response to enzyme replacement therapy (ERT). We identified deleterious variants in the genes involved in autophagy, immunity and bone metabolism, which contributed to the severity of the clinical symptoms observed in the LOPD patients. This study emphasizes the multisystem nature of LOPD and highlights the polygenic nature of the complex phenotype disclosed in these patients.

scholarly journals Long-term survival with sebelipase alfa enzyme replacement therapy in infants with rapidly progressive lysosomal acid lipase deficiency: final results from 2 open-label studies

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Suresh Vijay ◽  
Anais Brassier ◽  
Arunabha Ghosh ◽  
Simona Fecarotta ◽  
Florian Abel ◽  
...  
Keyword(s):  
Enzyme Replacement Therapy ◽  
Replacement Therapy ◽  
Phase 2 ◽  
Free Hemoglobin ◽  
Acid Lipase ◽  
Short Term ◽  
Open Label ◽  
Lysosomal Acid ◽  
Enzyme Replacement ◽  
Lysosomal Acid Lipase

Abstract Background If symptomatic in infants, the autosomal recessive disease lysosomal acid lipase deficiency (LAL-D; sometimes called Wolman disease or LAL-D/Wolman phenotype) is characterized by complete loss of LAL enzyme activity. This very rare, rapidly progressive form of LAL-D results in severe manifestations leading to failure to thrive and death, usually by 6 months of age. We report results from 2 open-label studies of enzyme replacement therapy with sebelipase alfa, a recombinant human LAL, in infants with LAL-D: the phase 2/3 Survival of LAL-D Infants Treated With Sebelipase Alfa (VITAL) study (NCT01371825) and a phase 2 dose-escalation study (LAL-CL08 [CL08]; NCT02193867). In both, infants received once-weekly intravenous infusions of sebelipase alfa. Results The analysis population contained 19 patients (9 in VITAL; 10 in CL08). Kaplan–Meier estimates of survival to 12 months and 5 years of age were 79% and 68%, respectively, in the combined population, and the median age of surviving patients was 5.2 years in VITAL and 3.2 years in CL08. In both studies, median weight-for-age, length-for-age, and mid-upper arm circumference-for-age z scores increased from baseline to end of study. Decreases in median liver and spleen volume over time were noted in both studies. Short-term transfusion-free hemoglobin normalization was achieved by 100% of patients eligible for assessment in VITAL, in an estimated median (95% confidence interval [CI]) time of 4.6 (0.3–16.6) months. In CL08, short-term transfusion-free hemoglobin normalization was achieved by 70% of patients eligible for assessment, in an estimated median (95% CI) time of 5.5 (3.7–19.6) months. No patient discontinued treatment because of treatment-emergent adverse events. Most infusion-associated reactions (94% in VITAL and 88% in CL08) were mild or moderate in severity. Conclusions The findings of these 2 studies of infants with rapidly progressive LAL-D demonstrated that enzyme replacement therapy with sebelipase alfa prolonged survival with normal psychomotor development, improved growth, hematologic parameters, and liver parameters, and was generally well tolerated, with an acceptable safety profile.

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