Project description:Antagonism of microRNA-122 in mice by systemically administered LNA-antimiR leads to up-regulation of a large set of predicted target mRNAs in the liver; MicroRNA-122 (miR-122) is an abundant liver-specific miRNA, implicated in fatty acid and cholesterol metabolism as well as hepatitis C viral replication. Here, we report that a systemically administered 16-nt, unconjugated LNA (locked nucleic acid)-antimiR oligonucleotide complementary to the 5' end of miR-122 leads to specific, dose-dependent silencing of miR-122 and shows no hepatotoxicity in mice. Antagonism of miR-122 is due to formation of stable heteroduplexes between the LNA-antimiR and miR-122 as detected by northern analysis. Fluorescence in situ hybridization demonstrated uptake of the LNA-antimiR in mouse liver cells, which was accompanied by markedly reduced hybridization signals for mature miR-122 in treated mice. Functional antagonism of miR-122 was inferred from a low cholesterol phenotype and de-repression within 24 h of 199 liver mRNAs showing significant enrichment for miR-122 seed matches in their 3' UTRs. Expression profiling extended to 3 weeks after the last LNA-antimiR dose revealed that most of the changes in liver gene expression were normalized to saline control levels coinciding with normalized miR-122 and plasma cholesterol levels. Combined, these data suggest that miRNA antagonists comprised of LNA are valuable tools for identifying miRNA targets in vivo and for studying the biological role of miRNAs and miRNA-associated gene-regulatory networks in a physiological context. Experiment Overall Design: Female NMRI mice were treated at day 2 with either 25mg/kg antimiR-122 (SPC3372) or vehicle (saline). Mice were sacrificied at day 3, 9 and 23 and liver RNA assayed. Three biological replicates for each of the six groups.
Project description:Antagonism of microRNA-122 in mice by systemically administered LNA-antimiR leads to up-regulation of a large set of predicted target mRNAs in the liver MicroRNA-122 (miR-122) is an abundant liver-specific miRNA, implicated in fatty acid and cholesterol metabolism as well as hepatitis C viral replication. Here, we report that a systemically administered 16-nt, unconjugated LNA (locked nucleic acid)-antimiR oligonucleotide complementary to the 5' end of miR-122 leads to specific, dose-dependent silencing of miR-122 and shows no hepatotoxicity in mice. Antagonism of miR-122 is due to formation of stable heteroduplexes between the LNA-antimiR and miR-122 as detected by northern analysis. Fluorescence in situ hybridization demonstrated uptake of the LNA-antimiR in mouse liver cells, which was accompanied by markedly reduced hybridization signals for mature miR-122 in treated mice. Functional antagonism of miR-122 was inferred from a low cholesterol phenotype and de-repression within 24 h of 199 liver mRNAs showing significant enrichment for miR-122 seed matches in their 3' UTRs. Expression profiling extended to 3 weeks after the last LNA-antimiR dose revealed that most of the changes in liver gene expression were normalized to saline control levels coinciding with normalized miR-122 and plasma cholesterol levels. Combined, these data suggest that miRNA antagonists comprised of LNA are valuable tools for identifying miRNA targets in vivo and for studying the biological role of miRNAs and miRNA-associated gene-regulatory networks in a physiological context. Keywords: compound treatment
Project description:To determine the effect of antimiR-122 administration on the mouse miRNome. To functionally investigate a possible link between miR-122 and iron metabolism we inhibited miR-122 by a single, intraperitoneal injection of Locked Nucleic Acid (LNA)-modified antimiR oligonucleotides into age- and sex-matched C57Bl/6 WT mice. To inhibit miR-122 specifically, we injected an antimiR compound with perfect complementarity to miR-122 [perfect match (PM); PM_antimiR-122]. As negative controls, mice were either injected with an LNA control compound with two mismatches (2MM, 2MM_antimiR-122) or the vehicle control (SAL; 0.9% NaCl). Mice were sacrificed three and six weeks after injection. Independent of treatment, mice were viable and exhibited no overt physical or behavioral abnormalities. To exclude that PM_antimiR-122 administration disturbs the expression of other miRNAs we analyzed miRNA expression profiles in the livers, hearts and spleens of the same mice.
Project description:For microRNA knockdown in vivo, a 15-mer LNA-antimiR oligonucleotide targeting mmu-miR-155 or an LNA control was administered to male 4-week-old C3H mice intravenously at a dose of 25 mg/kg per injection at days 1, 4 and 6 post-CVB3 infection. Samples were taken at 6 days post infection.
Project description:Transcriptional profiling of breast cancer cells comparing LNA-control transfected cells with cells transfected with LNA-antimiR-21.We searched for miR-21 targets by systematic screening of mRNA profiling of LNA-antimiR-21 transfected MCF-7 cells and MDA-MB-231 cells.
Project description:Transcriptional profiling of breast cancer cells comparing LNA-control transfected cells with cells transfected with LNA-antimiR-21.We searched for miR-21 targets by systematic screening of mRNA profiling of LNA-antimiR-21 transfected MCF-7 cells and MDA-MB-231 cells. Two-condition experiment, LNA-antimiR-21 Transfected vs. LNA-control Transfected MCF-7 cells. One replicate per array.
Project description:Heart failure with preserved ejection fraction (HFpEF) remains a major public health burden with increasing prevalence but only few effective therapies. Endothelial dysfunction and inflammation are identified as pathophysiological drivers of HFpEF disease progression. MicroRNAs are increasingly recognized as key regulators of these pathological processes, while antimiR-based therapies have been emerged as promising therapeutics in mice and humans. Therefore, we tested whether targeting miR-92a-3p inhibition is a promising therapeutic intervention to target HFpEF in vivo. By injection of locked nucleic acid (LNA)-based antimiR (LNA-92a) weekly, we demonstrate that inhibition of miR-92a-3p attenuates the development of diastolic dysfunction and left atrial dilation following experimental induction of HFpEF in mice. Indeed, LNA-92a depleted miR-92a-3p expression in the myocardium and peripheral blood, and derepressed predicted target genes in a cell type-specific manner. Furthermore, cell-type specific efficacy of LNA-92a treatment was assessed by single-nuclear RNA sequencing of HFpEF hearts either treated with LNA-92a or LNA-Control. Endothelial cells of LNA-92a treated mice showed normalized vascular gene expression and reduced gene signatures associated with endothelial-mesenchymal transition. Conclusion: This study demonstrates that LNA-based antimiR-92a is an effective therapeutic strategy to target diastolic dysfunction and left atrial dilation in HFpEF.