Altered Biodistribution and Hepatic Safety Profile of a Gapmer Antisense Oligonucleotide Bearing Guanidine-Bridged Nucleic Acids.

Guanidine-bridged nucleic acid (GuNA) is a novel 2',4'-bridged nucleic acid/locked nucleic acid (2',4'-BNA/LNA) analog containing cations that exhibit strong affinity for target RNA and superior nuclease resistance. In this study, antisense oligonucleotide (ASO) bearing GuNA was evaluated for target knockdown (KD) activity and tolerability. The GuNA ASO did not interfere with RNase H recruitment on the target RNA/ASO heteroduplex and did show potent target KD activity in a skeletal muscle-derived cell line equivalent to that of the LNA ASO under gymnotic conditions, whereas almost no KD activity was observed in a hepatocyte-derived cell line.

Reduction of Off-Target Effects of Gapmer Antisense Oligonucleotides by Oligonucleotide Extension.

Aim: Antisense oligonucleotide (ASO) has the potential to induce off-target effects by inadvertent binding of ASOs to unintended RNAs that have a sequence similar to the target RNA. In the present study, we focused on the association between oligonucleotide length and off-target effects. Oligonucleotide extension is assumed to have bilateral effects on hybridization-dependent changes in gene expression, i.

Prediction of human pharmacokinetics for low-clearance compounds using pharmacokinetic data from chimeric mice with humanized livers.

Development of low-clearance (CL) compounds that are slowly metabolized is a major goal in the pharmaceutical industry. However, the pursuit of low intrinsic CL (CL ) often leads to significant challenges in evaluating the pharmacokinetics of such compounds. Although in vitro-in vivo extrapolation is widely used to predict human CL, its application has been limited for low-CL compounds because of the low turnover of parent compounds in metabolic stability assays.

Metabolomic profiling of urine-derived extracellular vesicles from rat model of drug-induced acute kidney injury.

Extracellular vesicles (EVs) are lipid bilayer particles that are released by various cells and provide a real-time snapshot of the state of these cells in tissue in a noninvasive manner. EVs contain components, including mRNA, miRNAs, proteins, and metabolites. Therefore, EVs hold promise for the discovery of liquid biopsy-based biomarkers for disease diagnosis.

Evaluation of off-target effects of gapmer antisense oligonucleotides using human cells.

Antisense oligonucleotide (ASO) has the potential to induce off-target effects due to complementary binding between the ASO and unintended RNA with a sequence similar to the target RNA. Conventional animal studies cannot be used to assess toxicity induced by off-target effects because of differences in the genome sequence between humans and other animals. Consequently, the assessment of off-target effects with in silico analysis using a human RNA database and/or in vitro expression analysis using human cells has been proposed.

Evaluation of the effects of chemically different linkers on hepatic accumulations, cell tropism and gene silencing ability of cholesterol-conjugated antisense oligonucleotides.

Cholesterol conjugation of oligonucleotides is an attractive way to deliver the oligonucleotides specifically to the liver. However cholesterol-conjugated antisense oligonucleotides (ASOs) mainly accumulate in non-parenchymal cells (NPCs) such as Kupffer cells. In this study, to increase the hepatic accumulation of cholesterol-conjugated ASOs, we prepared a variety of linkers for cholesterol conjugation to anti-Pcsk9 ASOs and examined their effects on pharmacological parameters.

DNA/RNA heteroduplex oligonucleotide for highly efficient gene silencing.

Antisense oligonucleotides (ASOs) are recognized therapeutic agents for the modulation of specific genes at the post-transcriptional level. Similar to any medical drugs, there are opportunities to improve their efficacy and safety. Here we develop a short DNA/RNA heteroduplex oligonucleotide (HDO) with a structure different from double-stranded RNA used for short interfering RNA and single-stranded DNA used for ASO.

Amido-bridged nucleic acids with small hydrophobic residues enhance hepatic tropism of antisense oligonucleotides in vivo.

High scalability of a novel bicyclic nucleoside building block, amido-bridged nucleic acid (AmNA), to diversify pharmacokinetic properties of therapeutic antisense oligonucleotides is described. N2'-functionalization of AmNA with a variety of hydrophobic groups is straightforward. Combinations of these modules display similar antisense knockdown effects and improve cellular uptake, relative to sequence-matched conventional 2',4'-bridged nucleic acid (2',4'-BNA) in vivo.

Evaluation of multiple-turnover capability of locked nucleic acid antisense oligonucleotides in cell-free RNase H-mediated antisense reaction and in mice.

The multiple-turnover ability of a series of locked nucleic acid (LNA)-based antisense oligonucleotides (AONs) in the RNase H-mediated scission reaction was estimated using a newly developed cell-free reaction system. We determined the initial reaction rates of AONs under multiple-turnover conditions and found that among 24 AONs tested, AONs with melting temperatures (Tm) of 40°C-60°C efficiently elicit multiple rounds of RNA scission. On the other hand, by measuring Tm with two 10-mer RNAs partially complementary to AONs as models of cleaved 5' and 3' fragments of mRNA, we found that AONs require adequate binding affinity for efficient turnover activities.

Locked nucleic acid antisense inhibitor targeting apolipoprotein C-III efficiently and preferentially removes triglyceride from large very low-density lipoprotein particles in murine plasma.

A 20-mer phosphorothioate antisense oligodeoxyribonucleotide having locked nucleic acids (LNA-AON) was used to reduce elevated serum triglyceride levels in mice. We repeatedly administered LNA-AON, which targets murine apolipoprotein C-III mRNA, to high-fat-fed C57Bl/6J male mice for 2 weeks. The LNA-AON showed efficient dose-dependent reductions in hepatic apolipoprotein C-III mRNA and decreased serum apolipoprotein C-III protein concentrations, along with efficient dose-dependent reductions in serum triglyceride concentrations and attenuation of fat accumulation in the liver.

Cholesterol-lowering Action of BNA-based Antisense Oligonucleotides Targeting PCSK9 in Atherogenic Diet-induced Hypercholesterolemic Mice.

Recent findings in molecular biology implicate the involvement of proprotein convertase subtilisin/kexin type 9 (PCSK9) in low-density lipoprotein receptor (LDLR) protein regulation. The cholesterol-lowering potential of anti-PCSK9 antisense oligonucleotides (AONs) modified with bridged nucleic acids (BNA-AONs) including 2',4'-BNA (also called as locked nucleic acid (LNA)) and 2',4'-BNA(NC) chemistries were demonstrated both in vitro and in vivo. An in vitro transfection study revealed that all of the BNA-AONs induce dose-dependent reductions in PCSK9 messenger RNA (mRNA) levels concomitantly with increases in LDLR protein levels.

Superior Silencing by 2',4'-BNA(NC)-Based Short Antisense Oligonucleotides Compared to 2',4'-BNA/LNA-Based Apolipoprotein B Antisense Inhibitors.

The duplex stability with target mRNA and the gene silencing potential of a novel bridged nucleic acid analogue are described. The analogue, 2',4'-BNA(NC) antisense oligonucleotides (AONs) ranging from 10- to 20-nt-long, targeted apolipoprotein B. 2',4'-BNA(NC) was directly compared to its conventional bridged (or locked) nucleic acid (2',4'-BNA/LNA)-based counterparts.