Stability In Mice Research Articles

1037. Formulating and Testing of Targeted siRNA for Applications In Vivo

The use of RNAi to manipulate gene expression has become an invaluable tool in the elucidation of gene function. Although RNAi may have therapeutic potential, its successful application is limited by instability and poor delivery of synthetic small interfering RNAs (siRNAs) or vector-expressed short-hairpin RNAs (shRNAs) in mammalian systems. A comparative evaluation of the efficiency of siRNA versus plasmid-expressed indicated that siRNAs are more potent inhibitors of gene expression than shRNA however, the duration of silencing by siRNAs is shorter than for shRNAs. An evaluation of PEI versus Cys-Trp-Lys17-Cys to delivery siRNAs in vitro showed no difference in the efficiency of knockdown, suggesting that the transfection agent used does not affect siRNA potency. In an effort to improve in vivo stability and liver targetingefficiency, siRNA was formulated with glutaraldehyde-crosslinked glycopeptide PEG-peptide to form stabilized colloids. These formulations showed improved liver targeting efficiency and metabolic stability in mice. The results provide evidence of improved formulation strategies for siRNA utilizing cross-linked peptide gene delivery systems that may improve potency and duration of action in vivo.

2'-O-[2-[(N,N-dimethylamino)oxy]ethyl]-modified oligonucleotides inhibit expression of mRNA in vitro and in vivo.

Synthesis and antisense activity of oligonucleotides modified with 2'-O-[2-[(N,N-dimethylamino)oxy] ethyl] (2'-O-DMAOE) are described. The 2'-O-DMAOE-modified oligonucleotides showed superior metabolic stability in mice. The phosphorothioate oligonucleotide 'gapmers', with 2'-O-DMAOE- modified nucleoside residues at the ends and 2'-deoxy nucleosides residues in the central region, showed dose-dependent inhibition of mRNA expression in cell culture for two targets. 'Gapmer' oligonucleotides have one or two 2'-O-modified regions and a 2'-deoxyoligonucleotide phosphorothioate region that allows RNase H digestion of target mRNA. To determine the in vivo potency and efficacy, BalbC mice were treated with 2'-O-DMAOE gapmers and a dose-dependent reduction in the targeted C-raf mRNA expression was observed. Oligonucleotides with 2'-O-DMAOE modifications throughout the sequences reduced the intercellular adhesion molecule-1 (ICAM-1) protein expression very efficiently in HUVEC cells with an IC(50) of 1.8 nM. The inhibition of ICAM-1 protein expression by these uniformly modified 2'-O-DMAOE oligonucleotides may be due to selective interference with the formation of the translational initiation complex. These results demonstrate that 2'-O-DMAOE- modified oligonucleotides are useful for antisense-based therapeutics when either RNase H-dependent or RNase H-independent target reduction mechanisms are employed.

Synthesis and biological evaluation of cytogenin derivatives.

To enhance the stability in vivo, new derivatives of cytogenin were synthesized, and their biological activity and stability in mice were estimated. 2-(8-Hydroxy-6-methoxy-1-oxo-1H-2-benzopyran-3-yl)propionic acid (NM-3) was found to be the most stable among them. It modified collagen-induced arthritis in mice. It also showed potent anti-angiogenic activity in a mouse dorsal air sac assay.

Proteasome inhibition enhances the stability of mouse Cu/Zn superoxide dismutase with mutations linked to familial amyotrophic lateral sclerosis

Proteasome inhibition enhances the stability of mouse Cu/Zn superoxide dismutase with mutations linked to familial amyotrophic lateral sclerosis

Analysis of CAG trinucleotide repeats from mouse cDNA sequences.

A number of human single gene disorders are now known to result from abnormal expansion of trinucleotide repeats. Spinal muscular bulbar atrophy, myotonic dystrophy, Huntington's Disease, spinocerebellar ataxia and dentatorubral-pallidoluysian atrophy are all caused by expansions of CAG repeats. Abnormal expansion of trinucleotide repeats has only so far been described in humans, and no mouse models exist for these diseases. In order to investigate trinucleotide repeat stability in mice, the Genbank and EMBL nucleotide databases were screened to find genes containing CAG repeats. Of the sequences selected, 32 were from mouse, and in 12 of these the repeat was in transcribed sequence and contained at least seven perfect repeats. These repeats were then analysed by PCR to evaluate the degree of variability of repeat length in the various genes. Two of the genes containing variable length CAG repeats, seven in absentia homologue 1b (Sinh1b), and choline acetyl transferase (Chat), which had not previously been mapped in the mouse genome, were mapped by linkage analysis in an interspecific backcross. Sinh1b maps very distally on the X chromosome, and Chat maps to chromosome 14.

Capped oligodeoxynucleotide phosphorothioates. Pharmacokinetics and stability in mice.

Annals of the New York Academy of SciencesVolume 660, Issue 1 p. 318-320 Capped Oligodeoxynucleotide Phosphorothioates. Pharmacokinetics and Stability in Mice J. TEMSAMANI, J. TEMSAMANI Hybridon, Inc. One Innovation Drive Worcester, Massachusetts 01605Search for more papers by this authorJ.-Y. TANG, J.-Y. TANG Hybridon, Inc. One Innovation Drive Worcester, Massachusetts 01605Search for more papers by this authorSUDHIR AGRAWAL, SUDHIR AGRAWAL Worcester Foundation for Experimental Biology 222 Maple Avenue Shrewsbury, Massachusetts 01545Search for more papers by this author J. TEMSAMANI, J. TEMSAMANI Hybridon, Inc. One Innovation Drive Worcester, Massachusetts 01605Search for more papers by this authorJ.-Y. TANG, J.-Y. TANG Hybridon, Inc. One Innovation Drive Worcester, Massachusetts 01605Search for more papers by this authorSUDHIR AGRAWAL, SUDHIR AGRAWAL Worcester Foundation for Experimental Biology 222 Maple Avenue Shrewsbury, Massachusetts 01545Search for more papers by this author First published: October 1992 https://doi.org/10.1111/j.1749-6632.1992.tb21099.xCitations: 18AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume660, Issue1Antisense StrategiesOctober 1992Pages 318-320 RelatedInformation