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Nucleic Acids Research May 2024RNA interference (RNAi) is an endogenous process that can be harnessed using chemically modified small interfering RNAs (siRNAs) to potently modulate gene expression in...
RNA interference (RNAi) is an endogenous process that can be harnessed using chemically modified small interfering RNAs (siRNAs) to potently modulate gene expression in many tissues. The route of administration and chemical architecture are the primary drivers of oligonucleotide tissue distribution, including siRNAs. Independently of the nature and type, oligonucleotides are eliminated from the body through clearance tissues, where their unintended accumulation may result in undesired gene modulation. Divalent siRNAs (di-siRNAs) administered into the CSF induce robust gene silencing throughout the central nervous system (CNS). Upon clearance from the CSF, they are mainly filtered by the kidneys and liver, with the most functionally significant accumulation occurring in the liver. siRNA- and miRNA-induced silencing can be blocked through substrate inhibition using single-stranded, stabilized oligonucleotides called antagomirs or anti-siRNAs. Using APOE as a model target, we show that undesired di-siRNA-induced silencing in the liver can be mitigated through administration of liver targeting GalNAc-conjugated anti-siRNAs, without impacting CNS activity. Blocking unwanted hepatic APOE silencing achieves fully CNS-selective silencing, essential for potential clinical translation. While we focus on CNS/liver selectivity, coadministration of differentially targeting siRNA and anti-siRNAs can be adapted as a strategy to achieve tissue selectivity in different organ combinations.
Topics: Animals; Humans; Male; Mice; Acetylgalactosamine; Antagomirs; Apolipoproteins E; Central Nervous System; Gene Silencing; Liver; Mice, Inbred C57BL; MicroRNAs; RNA Interference; RNA, Small Interfering
PubMed: 38348876
DOI: 10.1093/nar/gkae100 -
Pathology, Research and Practice Sep 2019Arylsulfatases are lysosomal enzymes with important roles in the cell metabolism. Several subtypes of arylsulfatase are known, from A to K. Congenital deficiencies of... (Review)
Review
Arylsulfatases are lysosomal enzymes with important roles in the cell metabolism. Several subtypes of arylsulfatase are known, from A to K. Congenital deficiencies of arylsulfatases, especially A (ARSA) and B (ARSB), can induce metabolic disorders such as metachromatic leucodystrophy (ARSA deficiency) and Maroteaux-Lamy syndrome (ARSB deficiency). ARSA and ARSB pseudodeficiencies were recently described but their exact roles are far to be known. The aim of this review was to synthesize the literature data, combined with personal results, regarding the roles of ARSA and ARSB in non-tumor disorders but also carcinogenesis. Few than 50 published papers regard ARSA and ARSB expression in cancer. They suggest decreased activity of these arylsulfatases in most of carcinomas, compared with normal tissues. However, the clinical impact is still unknown. Further complex studies are necessary to be done, to understand the role of ARSA and ARSB expression in cancer.
Topics: Animals; Cerebroside-Sulfatase; Humans; Lysosomal Storage Diseases; N-Acetylgalactosamine-4-Sulfatase; Neoplasms
PubMed: 31262576
DOI: 10.1016/j.prp.2019.152516 -
The Journal of Biological Chemistry Jul 2023A primary pathology of Alzheimer's disease (AD) is amyloid β (Aβ) deposition in brain parenchyma and blood vessels, the latter being called cerebral amyloid angiopathy...
A primary pathology of Alzheimer's disease (AD) is amyloid β (Aβ) deposition in brain parenchyma and blood vessels, the latter being called cerebral amyloid angiopathy (CAA). Parenchymal amyloid plaques presumably originate from neuronal Aβ precursor protein (APP). Although vascular amyloid deposits' origins remain unclear, endothelial APP expression in APP knock-in mice was recently shown to expand CAA pathology, highlighting endothelial APP's importance. Furthermore, two types of endothelial APP-highly O-glycosylated APP and hypo-O-glycosylated APP-have been biochemically identified, but only the former is cleaved for Aβ production, indicating the critical relationship between APP O-glycosylation and processing. Here, we analyzed APP glycosylation and its intracellular trafficking in neurons and endothelial cells. Although protein glycosylation is generally believed to precede cell surface trafficking, which was true for neuronal APP, we unexpectedly observed that hypo-O-glycosylated APP is externalized to the endothelial cell surface and transported back to the Golgi apparatus, where it then acquires additional O-glycans. Knockdown of genes encoding enzymes initiating APP O-glycosylation significantly reduced Aβ production, suggesting this non-classical glycosylation pathway contributes to CAA pathology and is a novel therapeutic target.
Topics: Animals; Mice; Alzheimer Disease; Amyloid beta-Peptides; Amyloid beta-Protein Precursor; Cerebral Amyloid Angiopathy; Endothelial Cells; Glycosylation; Protein Transport; Neurons; Golgi Apparatus; Acetylgalactosamine
PubMed: 37302553
DOI: 10.1016/j.jbc.2023.104905 -
Drugs May 2021Givosiran (Givlaari) is an δ-aminolevulinic acid synthase 1 (ALAS1)-directed small interfering RNA (siRNA) approved for the treatment of acute hepatic porphyria (AHP).... (Review)
Review
Givosiran (Givlaari) is an δ-aminolevulinic acid synthase 1 (ALAS1)-directed small interfering RNA (siRNA) approved for the treatment of acute hepatic porphyria (AHP). In the phase 3 ENVISION trial, givosiran significantly reduced the annualized rate of composite porphyria attacks (i.e. attacks requiring hospitalization, urgent healthcare visit or intravenous hemin administration at home) compared with placebo in patients with recurrent acute intermittent porphyria (the most common type of AHP) attacks. Givosiran also improved several other outcomes, including hemin use and pain (the cardinal symptom of AHP). While generally well tolerated with an acceptable safety profile, the drug may increase the risk of hepatic and kidney adverse events. Givosiran offers the convenience of once-monthly subcutaneous administration. Available evidence indicates that givosiran is an important newer therapeutic option for patients with AHP and severe recurrent attacks.
Topics: 5-Aminolevulinate Synthetase; Acetylgalactosamine; Acute Kidney Injury; Chemical and Drug Induced Liver Injury; Drug Interactions; Hemin; Hospitalization; Humans; Pain; Porphobilinogen Synthase; Porphyria, Acute Intermittent; Porphyrias, Hepatic; Pyrrolidines; RNA, Small Interfering; Randomized Controlled Trials as Topic; Severity of Illness Index
PubMed: 33871817
DOI: 10.1007/s40265-021-01511-3 -
International Journal of Molecular... Dec 2021Mucopolysaccharidosis type VI, or Maroteaux-Lamy syndrome, is a rare, autosomal recessive genetic disease, mainly affecting the pediatric age group. The disease is due... (Review)
Review
Mucopolysaccharidosis type VI, or Maroteaux-Lamy syndrome, is a rare, autosomal recessive genetic disease, mainly affecting the pediatric age group. The disease is due to pathogenic variants of the gene, coding for the lysosomal hydrolase N-acetylgalactosamine 4-sulfatase (arylsulfatase B, ASB). The enzyme deficit causes a pathological accumulation of the undegraded glycosaminoglycans dermatan-sulphate and chondroitin-sulphate, natural substrates of ASB activity. Intracellular and extracellular deposits progressively take to a pathological scenario, often severe, involving most organ-systems and generally starting from the osteoarticular apparatus. Neurocognitive and behavioral abilities, commonly described as maintained, have been actually investigated by few studies. The disease, first described in 1963, has a reported prevalence between 0.36 and 1.3 per 100,000 live births across the continents. With this paper, we wish to contribute an updated overview of the disease from the clinical, diagnostic, and therapeutic sides. The numerous in vitro and in vivo preclinical studies conducted in the last 10-15 years to dissect the disease pathogenesis, the efficacy of the available therapeutic treatment (enzyme replacement therapy), as well as new therapies under study are here described. This review also highlights the need to identify new disease biomarkers, potentially speeding up the diagnostic process and the monitoring of therapeutic efficacy.
Topics: Chondroitin Sulfates; Enzyme Replacement Therapy; Glycosaminoglycans; Humans; Mucopolysaccharidosis VI; N-Acetylgalactosamine-4-Sulfatase
PubMed: 34948256
DOI: 10.3390/ijms222413456 -
Journal of Molecular Medicine (Berlin,... Oct 2022Polypeptide N-acetylgalactosamine transferase 3 (ppGalNAc-T3) is an enzyme involved in the initiation of O-GalNAc glycan biosynthesis. Acting as a writer of frequent... (Review)
Review
Polypeptide N-acetylgalactosamine transferase 3 (ppGalNAc-T3) is an enzyme involved in the initiation of O-GalNAc glycan biosynthesis. Acting as a writer of frequent post-translational modification (PTM) on human proteins, ppGalNAc-T3 has key functions in the homeostasis of human cells and tissues. We review the relevant roles of this molecule in the biosynthesis of O-GalNAc glycans, as well as in biological functions related to human physiological and pathological conditions. With main emphasis in ppGalNAc-T3, we draw attention to the different ways involved in the modulation of ppGalNAc-Ts enzymatic activity. In addition, we take notice on recent reports of ppGalNAc-T3 having different subcellular localizations, highlight critical intrinsic and extrinsic functions in cellular physiology that are exerted by ppGalNAc-T3-synthesized PTMs, and provide an update on several human pathologies associated with dysfunctional ppGalNAc-T3. Finally, we propose biotechnological tools as new therapeutic options for the treatment of pathologies related to altered ppGalNAc-T3. KEY MESSAGES: ppGalNAc-T3 is a key enzyme in the human O-GalNAc glycans biosynthesis. enzyme activity is regulated by PTMs, lectin domain and protein-protein interactions. ppGalNAc-T3 is located in human Golgi apparatus and cell nucleus. ppGalNAc-T3 has a central role in cell physiology as well as in several pathologies. Biotechnological tools for pathological management are proposed.
Topics: Cell Physiological Phenomena; Humans; N-Acetylgalactosaminyltransferases; Peptides; Polysaccharides; Protein Processing, Post-Translational; Transferases; Polypeptide N-acetylgalactosaminyltransferase
PubMed: 36056254
DOI: 10.1007/s00109-022-02249-5 -
Blood Nov 2023Hereditary transthyretin amyloidosis (ATTRv) is a rare autosomal dominant adult-onset disorder caused by point mutations in the transthyretin (TTR) gene encoding TTR,...
Hereditary transthyretin amyloidosis (ATTRv) is a rare autosomal dominant adult-onset disorder caused by point mutations in the transthyretin (TTR) gene encoding TTR, also known as prealbumin. ATTRv survival ranges from 3 to 10 years, and peripheral nervous system and heart are usually the 2 main tissues affected, although central nervous system and eye may also be involved. Because the liver is the main TTR protein secretor organ, it has been the main target of treatments developed these last years, including liver transplantation, which has been shown to significantly increase survival in a subset of patients carrying the so-called "early-onset Val30Met" TTR gene mutation. More recently, treatments targeting hepatic TTR RNA have been developed. Hepatic TTR RNA targeting is performed using RNA interference (RNAi) and antisense oligonucleotide (ASO) technologies involving lipid nanoparticle carriers or N-acetylgalactosamine fragments. RNAi and ASO treatments induce an 80% decrease in TTR liver production for a period of 1 to 12 weeks. ASO and RNAi phase 3 trials in patients with TTR-related polyneuropathy have shown a positive impact on neuropathy clinical scores and quality of life end points, and delayed RNAi treatment negatively affects survival. Clinical trials specifically investigating RNAi therapy in TTR cardiomyopathy are underway. Hepatic RNA targeting has revolutionized ATTRv treatment and may allow for the transforming a fatal disease into a treatable disorder. Because retina and choroid plexus secrete limited quantities of TTR protein, both tissues are now seen as the next targets for fully controlling the disease.
Topics: Adult; Humans; Oligonucleotides, Antisense; RNA Interference; Quality of Life; CRISPR-Cas Systems; Amyloid Neuropathies, Familial; Oligonucleotides; RNA
PubMed: 37624911
DOI: 10.1182/blood.2023019884 -
Arteriosclerosis, Thrombosis, and... Dec 2023Blood pressure management involves antihypertensive therapies blocking the renin-angiotensin system (RAS). Yet, it might be inadequate due to poor patient adherence or... (Review)
Review
Blood pressure management involves antihypertensive therapies blocking the renin-angiotensin system (RAS). Yet, it might be inadequate due to poor patient adherence or the so-called RAS escape phenomenon, elicited by the compensatory renin elevation upon RAS blockade. Recently, evidence points toward targeting hepatic AGT (angiotensinogen) as a novel approach to block the RAS pathway that could circumvent the RAS escape phenomenon. Removing AGT, from which all angiotensins originate, should prevent further angiotensin generation, even when renin rises. Furthermore, by making use of a trivalent -acetylgalactosamine ligand-conjugated small interfering RNA that specifically targets the degradation of hepatocyte-produced mRNAs in a highly potent and specific manner, it may be possible in the future to manage hypertension with therapy that is administered 1 to 2× per year, thereby supporting medication adherence. This review summarizes all current findings on AGT small interfering RNA in preclinical models, making a comparison versus classical RAS blockade with either ACE (angiotensin-converting enzyme) inhibitors or AT1 (angiotensin II type 1) receptor antagonists and AGT suppression with antisense oligonucleotides. It ends with discussing the first-in-human study with AGT small interfering RNA.
Topics: Humans; Acetylgalactosamine; Angiotensin II Type 1 Receptor Blockers; Angiotensin-Converting Enzyme Inhibitors; Angiotensinogen; Blood Pressure; Hypertension; Renin; Renin-Angiotensin System; RNA, Small Interfering
PubMed: 37855126
DOI: 10.1161/ATVBAHA.123.319897 -
Current Atherosclerosis Reports May 2024Here, we summarize the key findings from preclinical studies that tested the concept that editing of hepatic genes can lower plasma low-density lipoprotein... (Review)
Review
PURPOSE OF REVIEW
Here, we summarize the key findings from preclinical studies that tested the concept that editing of hepatic genes can lower plasma low-density lipoprotein (LDL)-cholesterol levels to subsequently reduce atherosclerotic cardiovascular disease risk.
RECENT FINDINGS
Selective delivery of clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9)-mediated gene editing tools targeting proprotein convertase subtilisin/kexin type 9 (PCSK9) to hepatocytes, i.e., through encapsulation into N-acetylgalactosamine-coupled lipid nanoparticles, is able to induce a stable ~ 90% decrease in plasma PCSK9 levels and a concomitant 60% reduction in LDL-cholesterol levels in mice and non-humane primates. Studies in mice have shown that this state-of-the-art technology can be extended to include additional targets related to dyslipidemia such as angiopoietin-like 3 and several apolipoproteins. The use of gene editors holds great promise to lower plasma LDL-cholesterol levels also in the human setting. However, gene editing safety has to be guaranteed before this approach can become a clinical success.
Topics: Gene Editing; Humans; Animals; Hypercholesterolemia; Genetic Therapy; Proprotein Convertase 9; Cholesterol, LDL; CRISPR-Cas Systems
PubMed: 38498115
DOI: 10.1007/s11883-024-01198-3 -
Expert Opinion on Biological Therapy Aug 2019The development of new biologic agents able to restore thrombin generation has become the focus of innovation in hemophilia management. There is growing interest in the... (Review)
Review
INTRODUCTION
The development of new biologic agents able to restore thrombin generation has become the focus of innovation in hemophilia management. There is growing interest in the proposal of novel, non-replacement therapy with alternative mechanisms of action and route of administration, hoping to solve still unmet needs in treatment of hemophilic patients with or without inhibitors.
AREAS COVERED
The review describes the new molecules, in particular the bi-specific antibody mimicking the coagulation function of FVIII and/or those which work by inhibiting the natural anticoagulants, their mechanism of action and the results of ongoing clinical trials.
EXPERT OPINION
Exciting results in enhancing the protection against bleeding and improving quality of life are emerging from clinical trials. However, these molecules with their mechanisms of action also open new problems. Treatment of bleeding and management of surgery in subjects with a rebalanced hemostasis may be difficult, especially for the lack of laboratory tests perfectly reflecting the coagulation status. A careful surveillance is required to evaluate the risk of thrombotic complication in patients with rebalanced hemostasis, in addition to understand whether these new products offer the same protection on joints as regular prophylaxis with the missing clotting factors.
Topics: Acetylgalactosamine; Animals; Antibodies, Bispecific; Antibodies, Monoclonal, Humanized; Hemophilia A; Hemostasis; Humans; RNA, Small Interfering; Randomized Controlled Trials as Topic
PubMed: 31039049
DOI: 10.1080/14712598.2019.1614163