Search results for "lysosomes"
showing 10 items of 99 documents
CNS-Targeting Therapies for Lysosomal Storage Diseases: Current Advances and Challenges.
2020
During the past decades, several therapeutic approaches have been developed and made rapidly available for many patients afflicted with lysosomal storage disorders (LSDs), inborn organelle disorders with broad clinical manifestations secondary to the progressive accumulation of undegraded macromolecules within lysosomes. These conditions are individually rare, but, collectively, their incidence ranges from 1 in 2,315 to 7,700 live-births. Most LSDs are manifested by neurological symptoms or signs, including developmental delay, seizures, acroparesthesia, motor weakness, and extrapyramidal signs. The chronic and later-onset clinical forms are at one end of the continuum spectrum and are char…
Enzyme replacement therapy with recombinant pro-CTSD (cathepsin D) corrects defective proteolysis and autophagy in neuronal ceroid lipofuscinosis
2019
CTSD (cathepsin D) is one of the major lysosomal proteases indispensable for the maintenance of cellular proteostasis by turning over substrates of endocytosis, phagocytosis and autophagy. Consequently, CTSD deficiency leads to a strong impairment of the lysosomal-autophagy machinery. In mice and humans CTSD dysfunction underlies the congenital variant (CLN10) of neuronal ceroid lipofuscinosis (NCL). NCLs are distinct lysosomal storage disorders (LSDs) sharing various hallmarks, namely accumulation of protein aggregates and ceroid lipofuscin leading to neurodegeneration and blindness. The most established and clinically approved approach to treat LSDs is enzyme replacement therapy (ERT) aim…
Flow cytometric DNA analysis and lysosomal cathepsins B and L in locally advanced laryngeal cancer. Relationship with clinicopathologic parameters an…
1995
Background. The traditional factors of locally advanced laryngeal squamous cell carcinoma (LSCC) have limited predictive value for the identification of high risk patients. Therefore, it is extremely important to define prognostic factors that identify the more aggressive types. Reliable and reproducible prognostic indicators are being investigated to help clinicians identify high risk groups and address more rational treatment. Methods. Flow cytometric DNA ploidy and S‐phase fraction (SPF) measurements were performed on frozen tumor tissues from a consecutive series of 71 patients with Stage III and IV LSCC. Lysosomal cathepsin B and L activity levels were determined biochemically in match…
AISF update on the diagnosis and management of adult-onset lysosomal storage diseases with hepatic involvement.
2020
Lysosomal storage diseases (LSDs) are a heterogeneous group of inherited disorders caused by loss-of-function mutations in genes encoding for lysosomal enzymes/proteins. The consequence is a progressive accumulation of substrates in these intracellular organelles, resulting in cellular and tissue damage. The overall incidence is about 1/8000 live births, but is likely underestimated. LSDs are chronic progressive multi-systemic disorders, generally presenting with visceromegaly, and involvement of the central nervous system, eyes, the skeleton, and the respiratory and cardiovascular systems. The age at onset and phenotypic expression are highly variable, according to the specific enzymatic d…
Lysosomal cathepsins B and L and Stefin A blood levels in patients with hepatocellular carcinoma and/or liver cirrhosis: potential clinical implicati…
1997
The serum levels of lysosomal cathepsin B and L and Stefin A, an intracellular inhibitor of these proteolytic enzymes, were determined in patients with hepatocellular carcinoma (HCC) and/or liver cirrhosis (LC) and correlated with some clinical and biochemical parameters of these diseases. Cathepsin B serum levels were increased in HCC and in LC patients as compared to normal subjects (p < 0.001). However no difference was observed between HCC and LC groups. Interestingly, a significant relationship was evidenced between cathepsin B serum content and the grade of severity of cirrhosis (r = 0.41; p < 0.001). Cathepsin L was significantly elevated only in sera of cancer patients as comp…
Hearing impairment as an early sign of alpha-mannosidosis in children with a mild phenotype: Report of seven new cases.
2019
Alpha-mannosidosis (AM) is a very rare (prevalence: 1/500000 births) autosomal recessive lysosomal storage disorder. It is characterized by multi-systemic involvement associated with progressive intellectual disability, hearing loss, skeletal anomalies, and coarse facial features. The spectrum is wide, from very severe and lethal to a milder phenotype that usually progresses slowly. AM is caused by a deficiency of lysosomal alpha-mannosidase. A diagnosis can be established by measuring the activity of lysosomal alpha-mannosidase in leucocytes and screening for abnormal urinary excretion of mannose-rich oligosaccharides. Genetic confirmation is obtained with the identification of MAN2B1 muta…
Studies on the subcellular pathophysiology of sublethal chronic cell injury.
1974
Summary This paper summarizes some of the important subcellular events occurring after chronic sublethal cell injury. Chronic cell injury is defined as the result of injurious stimuli which permit cell survival though in altered steady states for protracted periods of time. The importance of ultrastructural and biochemical studies of these phenomena is emphasized. Among the phenomena discussed are alterations in lysosomes, cellular hypertrophy, fatty metamorphosis, alterations in microfilaments and microtubules, alterations in mechanisms of transcription and replication, disturbances in the cell surface and transport across the cell membrane, and alterations in intracellular transport.
Phosphomannosyl receptors of lysosomal enzymes of skeletal muscle in neuromuscular diseases.
1988
The phosphomannosyl receptor system is responsible for both the receptor-mediated endocytosis and the intracellular transport of lysosomal enzymes. In the present study this receptor system was examined in affected muscles of patients with various neuromuscular diseases. The total activity of beta-N-acetyl-glucosaminidase, a marker enzyme of lysosomal hydrolases, was significantly elevated in the patients with myopathies (polymyositis and muscular dystrophies) but only slightly increased in those with neurogenic muscle atrophies (amyotrophic lateral sclerosis, polyneuropathy or other neurogenic muscle disease). The increase was most prominent in the group of polymyositis. The content of pho…
Lysosomal aspartic and cysteine proteinases serum levels in patients with pancreatic cancer or pancreatitis
1997
Lysosomal cathepsins D (CD), B (CB), and L (CL) serum levels were determined by immunoassays in patients with chronic (CHP) or acute (AP) pancreatitis and in patients with ductal pancreatic carcinoma (DPC) and correlated with some biological and clinical parameters of this tumor. CB serum concentrations significantly higher than those measured in healthy subjects (NS) were observed in CHP, AP, and DPC patients (p < 0.01). However, no significant difference was noted among these groups. Increased CL serum levels were evident only in cancer patients compared to NS, AP, or CHP groups (p < 0.05), while no difference was observed among these groups. Elevated CD serum values were observed i…
Morphologic diagnosis in neuronal ceroid lipofuscinosis.
1997
Morphologic pathology in NCL is marked by two processes, the interaction of which has not yet been completely clarified: 1) degeneration of nerve cells, foremost in the cerebral cortex, resulting in considerable cerebral atrophy in early childhood forms, likely responsible for clinical and neuroradiological findings; 2) widespread accumulation of autofluorescent lysosomal lipopigments of varying ultrastructure, the demonstration of which is still largely responsible for diagnostic recognition of an individual patient's NCL. Numerous tissues and organs are available for biopsy, among them brain (historical), rectum (still favoured by some), skeletal muscle and peripheral nerves (largely by c…