Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 6 de 6
Filter
Add more filters










Database
Language
Publication year range
1.
Amyloid ; 23(3): 148-157, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27355239

ABSTRACT

Transthyretin amyloidosis (ATTR amyloidosis) is a rare disease that results from the deposition of misfolded transthyretin (TTR) protein from the plasma into tissues as amyloid fibrils, leading to polyneuropathy and cardiomyopathy. IONIS-TTRRx (ISIS 420915) is a 2nd-Generation 2'-O-(2-methoxyethyl) modified "2'-MOE" antisense oligonucleotide (ASO) that targets the TTR RNA transcript and reduces the levels of the TTR transcript through an RNaseH1 mechanism of action, leading to reductions in both mutant and wild-type TTR protein. The activity of IONIS-TTRRx to decrease TTR protein levels was studied in transgenic mice bearing the Ile84Ser human TTR mutant, in cynomolgus monkeys and in healthy human volunteers. Robust (>80%) reductions of plasma TTR protein were obtained in all three species treated with IONIS-TTRRx, which in mice and monkeys was associated with substantial reductions in hepatic TTR RNA levels. These effects were dose-dependent and lasted for weeks post-dosing. In a Phase 1 healthy volunteer study, treatment with IONIS-TTRRx for four weeks was well tolerated without any remarkable safety issues. TTR protein reductions up to 96% in plasma were observed. These nonclinical and clinical results support the ongoing Phase 3 development of IONIS-TTRRx in patients with ATTR amyloidosis.


Subject(s)
Hepatocytes/metabolism , Liver/metabolism , Oligonucleotides, Antisense/pharmacokinetics , Prealbumin/antagonists & inhibitors , RNA, Messenger/antagonists & inhibitors , Ribonuclease H/metabolism , Adolescent , Adult , Amyloid Neuropathies, Familial/therapy , Animals , Double-Blind Method , Female , Gene Expression , Healthy Volunteers , Hep G2 Cells , Hepatocytes/cytology , Humans , Macaca fascicularis , Male , Mice , Mice, Transgenic , Middle Aged , Oligonucleotides, Antisense/administration & dosage , Prealbumin/biosynthesis , Prealbumin/genetics , Primary Cell Culture , RNA Cleavage , RNA, Messenger/biosynthesis , RNA, Messenger/genetics
2.
Invest Ophthalmol Vis Sci ; 56(11): 6362-75, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26436889

ABSTRACT

PURPOSE: To preserve photoreceptor cell structure and function in a rodent model of retinitis pigmentosa with P23H rhodopsin by selective inhibition of the mutant rhodopsin allele using a second generation antisense oligonucleotide (ASO). METHODS: Wild-type mice and rats were treated with ASO by intravitreal (IVT) injection and rhodopsin mRNA and protein expression were measured. Transgenic rats expressing the murine P23H rhodopsin gene (P23H transgenic rat Line 1) were administered either a mouse-specific P23H ASO or a control ASO. The contralateral eye was injected with PBS and used as a comparator control. Electroretinography (ERG) measurements and analyses of the retinal outer nuclear layer were conducted and correlated with rhodopsin mRNA levels. RESULTS: Rhodopsin mRNA and protein expression was reduced after a single ASO injection in wild-type mice with a rhodopsin-specific ASO. Transgenic rat eyes that express a murine P23H rhodopsin gene injected with a murine P23H ASO had a 181 ± 39% better maximum amplitude response (scotopic a-wave) as compared with contralateral PBS-injected eyes; the response in control ASO eyes was not significantly different from comparator contralateral eyes. Morphometric analysis of the outer nuclear layer showed a significantly thicker nuclear layer in eyes injected with murine P23H ASO (18%) versus contralateral PBS-injected eyes. CONCLUSIONS: Allele-specific ASO-mediated knockdown of mutant P23H rhodopsin expression slowed the rate of photoreceptor degeneration and preserved the function of photoreceptor cells in eyes of the P23H rhodopsin transgenic rat. Our data indicate that ASO treatment is a potentially effective therapy for the treatment of retinitis pigmentosa.


Subject(s)
Gene Expression Regulation , Macular Degeneration/prevention & control , Oligonucleotides, Antisense/genetics , RNA, Messenger/genetics , Rhodopsin/genetics , Alleles , Animals , Blotting, Western , Disease Models, Animal , Electroretinography , Macular Degeneration/genetics , Macular Degeneration/metabolism , Male , Mice , Rats , Rats, Transgenic , Real-Time Polymerase Chain Reaction , Rhodopsin/biosynthesis
3.
J Clin Invest ; 123(4): 1531-41, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23524968

ABSTRACT

ß-Thalassemia and HFE-related hemochromatosis are 2 of the most frequently inherited disorders worldwide. Both disorders are characterized by low levels of hepcidin (HAMP), the hormone that regulates iron absorption. As a consequence, patients affected by these disorders exhibit iron overload, which is the main cause of morbidity and mortality. HAMP expression is controlled by activation of the SMAD1,5,8/SMAD4 complex. TMPRSS6 is a serine protease that reduces SMAD activation and blocks HAMP expression. We identified second generation antisense oligonucleotides (ASOs) targeting mouse Tmprss6. ASO treatment in mice affected by hemochromatosis (Hfe(-/-)) significantly decreased serum iron, transferrin saturation and liver iron accumulation. Furthermore, ASO treatment of mice affected by ß-thalassemia (HBB(th3/+) mice, referred to hereafter as th3/+ mice) decreased the formation of insoluble membrane-bound globins, ROS, and apoptosis, and improved anemia. These animals also exhibited lower erythropoietin levels, a significant amelioration of ineffective erythropoiesis (IE) and splenomegaly, and an increase in total hemoglobin levels. These data suggest that ASOs targeting Tmprss6 could be beneficial in individuals with hemochromatosis, ß-thalassemia, and related disorders.


Subject(s)
Hemochromatosis/therapy , Membrane Proteins/genetics , Serine Endopeptidases/genetics , beta-Thalassemia/therapy , Animals , Antimicrobial Cationic Peptides/genetics , Antimicrobial Cationic Peptides/metabolism , Cells, Cultured , Female , Gene Knockdown Techniques , Hemochromatosis/blood , Hemochromatosis/genetics , Hemochromatosis Protein , Hepatocytes/metabolism , Hepcidins , Histocompatibility Antigens Class I/genetics , Histocompatibility Antigens Class I/metabolism , Iron/blood , Iron/metabolism , Liver/metabolism , Male , Membrane Proteins/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Oligonucleotides, Antisense/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Serine Endopeptidases/metabolism , Spleen/metabolism , Spleen/pathology , Transferrin/metabolism , beta-Thalassemia/blood , beta-Thalassemia/genetics
4.
Nat Neurosci ; 15(11): 1488-97, 2012 Nov.
Article in English | MEDLINE | ID: mdl-23023293

ABSTRACT

FUS/TLS (fused in sarcoma/translocated in liposarcoma) and TDP-43 are integrally involved in amyotrophic lateral sclerosis (ALS) and frontotemporal dementia. We found that FUS/TLS binds to RNAs from >5,500 genes in mouse and human brain, primarily through a GUGGU-binding motif. We identified a sawtooth-like binding pattern, consistent with co-transcriptional deposition of FUS/TLS. Depletion of FUS/TLS from the adult nervous system altered the levels or splicing of >950 mRNAs, most of which are distinct from RNAs dependent on TDP-43. Abundance of only 45 RNAs was reduced after depletion of either TDP-43 or FUS/TLS from mouse brain, but among these were mRNAs that were transcribed from genes with exceptionally long introns and that encode proteins that are essential for neuronal integrity. Expression levels of a subset of these were lowered after TDP-43 or FUS/TLS depletion in stem cell-derived human neurons and in TDP-43 aggregate-containing motor neurons in sporadic ALS, supporting a common loss-of-function pathway as one component underlying motor neuron death from misregulation of TDP-43 or FUS/TLS.


Subject(s)
Amyotrophic Lateral Sclerosis/metabolism , DNA-Binding Proteins/metabolism , Frontotemporal Dementia/metabolism , RNA Precursors/metabolism , RNA, Messenger/metabolism , RNA-Binding Protein FUS/metabolism , Adaptor Proteins, Signal Transducing , Amyotrophic Lateral Sclerosis/genetics , Amyotrophic Lateral Sclerosis/pathology , Animals , Autophagy-Related Proteins , Brain/metabolism , Brain/pathology , Carrier Proteins/genetics , Carrier Proteins/metabolism , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Cell Line, Transformed , DNA-Binding Proteins/deficiency , DNA-Binding Proteins/genetics , Excitatory Amino Acid Transporter 2/genetics , Excitatory Amino Acid Transporter 2/metabolism , Female , Frontotemporal Dementia/genetics , Frontotemporal Dementia/pathology , Gene Expression Profiling , Gene Expression Regulation/genetics , Histone-Lysine N-Methyltransferase/metabolism , Humans , Immunoprecipitation , Kv Channel-Interacting Proteins/metabolism , Membrane Proteins/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Motor Neurons/metabolism , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Neural Cell Adhesion Molecules/metabolism , Neural Stem Cells/metabolism , Neurofilament Proteins/metabolism , Oligonucleotide Array Sequence Analysis , Protein Binding/genetics , Protein Structure, Tertiary/genetics , RNA Precursors/genetics , RNA Splicing/genetics , RNA, Messenger/genetics , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , RNA-Binding Protein FUS/deficiency , RNA-Binding Protein FUS/genetics , Shal Potassium Channels/metabolism , Spinal Cord/metabolism , Ubiquitin-Protein Ligases/metabolism , tau Proteins/genetics , tau Proteins/metabolism
5.
Mol Ther Nucleic Acids ; 1: e9, 2012 Feb 07.
Article in English | MEDLINE | ID: mdl-23344724

ABSTRACT

Mice deficient for the cellular prion protein (PrP(C)) do not develop prion disease; accordingly, gene-based strategies to diminish PrP(C) expression are of interest. We synthesized a series of chemically modified antisense oligonucleotides (ASOs) targeted against mouse Prnp messenger RNA (mRNA) and identified those that were most effective in decreasing PrP(C) expression. Those ASOs were also evaluated in scrapie-infected cultured cells (ScN2a) for their efficacy in diminishing the levels of the disease-causing prion protein (PrP(Sc)). When the optimal ASO was infused intracerebrally into FVB mice over a 14-day period beginning 1 day after infection with the Rocky Mountain Laboratory (RML) strain of mouse prions, a prolongation of the incubation period of almost 2 months was observed. Whether ASOs can be used to develop an effective therapy for patients dying of Creutzfeldt-Jakob disease remains to be established.

6.
Nucleic Acids Res ; 30(19): 4295-304, 2002 Oct 01.
Article in English | MEDLINE | ID: mdl-12364609

ABSTRACT

An mRNA transcript contains many potential antisense oligodeoxynucleotide target sites. Identification of the most efficacious targets remains an important and challenging problem. Building on separate work that revealed a strong correlation between the inclusion of short sequence motifs and the activity level of an oligo, we have developed a predictive artificial neural network system for mapping tetranucleotide motif content to antisense oligo activity. Trained for high-specificity prediction, the system has been cross-validated against a database of 348 oligos from the literature and a larger proprietary database of 908 oligos. In cross- validation tests the system identified effective oligos (i.e. oligos capable of reducing target mRNA expression to <25% that of the control) with 53% accuracy, in contrast to the <10% success rates commonly reported for trial-and-error oligo selection, suggesting a possible 5-fold reduction in the in vivo screening required to find an active oligo. We have implemented a web interface to a trained neural network. Given an RNA transcript as input, the system identifies the most likely oligo targets and provides estimates of the probabilities that oligos targeted against these sites will be effective.


Subject(s)
Neural Networks, Computer , Oligodeoxyribonucleotides, Antisense/genetics , Binding Sites/genetics , Linear Models , Oligodeoxyribonucleotides, Antisense/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL
...