Chemically modified siRNA prolonged RNA interference in renal disease.
ABSTRACT We previously demonstrated that transfection of synthetic short interfering RNAs (siRNAs) targeting against TGF-beta1 could be effective and therapeutic in silencing TGF-beta1 expression in glomerulus, thereby ameliorated the progression of matrix expansion in anti-Thy-1 model of glomerulonephritis. However, a major concern in applying RNAi to gene therapy is the prolonged existence of silencing potential in vivo.
We examined the duration of siRNA stability in kidney and muscle, and checked the tissue distribution of siRNase, eri-1. Thereafter, we tested the effect of chemically modified siRNA called siSTABLE on progressive glomerulosclerosis model.
A single introduction of siRNA for EGFP (siEGFP) or its expression vector into kidney resulted in the reduction of masangial EGFP expression only for up to two weeks, while transfection of siEGFP into the pretibial muscle silenced EGFP expression unexpectedly for more than 90 days. These observations could be explained by the different expression of eri-1 between kidney and muscle. In addition, transfection of ERI-1-resistant siSTABLE for TGF-beta1 significantly reduced glomerular matrix deposition in progressive glomerulosclerosis model.Conclusion: Treatment with siRNA resistant to eri-1 may be effective and promising strategy for progressive renal disease.
Article: RNA interference for apoptosis signal-regulating kinase-1 (ASK-1) rescues photoreceptor death in the rd1 mouse.[show abstract] [hide abstract]
ABSTRACT: To evaluate whether RNA interference against apoptosis signal-regulating kinase-1 (ASK-1), a gene involved in stress-induced apoptosis, inhibits photoreceptor death in retinal degeneration 1 (rd1) mice. Retinal explants from rd1 mice were subjected to organ cultures on postnatal day 9 (P9). Short interfering RNA (siRNA) for ASK-1 was transfected into cultured retinas at the onset of experiments. Real-time PCR was performed to evaluate the natural expression of ASK-1 mRNA and its inhibition with siRNA. Retinal explants were fixed at P13 and P16, and consecutive cryosections were prepared. Histological and immunohistochemical examinations including TUNEL assays were performed. In preliminary experiments, the incorporation of fluorescent siRNA was found in cells in the outer nuclear and inner nuclear layers on the day following transfection. The expression of ASK-1 mRNA increased with time, which was suppressed more than 70% by siRNA. ASK-1 immunopositive cells were found mostly in the outer nuclear layers, and the number of immunopositive cells was remarkably reduced in retinas treated with siRNA for ASK-1 compared to untreated controls. The thickness of outer nuclear layers of control retinas decreased with time, while the thickness of siRNA transfected retinas was significantly preserved compared to control at P16 (p=0.0021). In TUNEL assays, siRNA for ASK-1 significantly decreased TUNEL-positive cells (49% and 42% of controls at P13 and 16, p=0.039 and 0.0028, respectively). RNA interference against ASK-1 may provide a benefit by inhibiting photoreceptor apoptosis in rd1 mice.Molecular vision 02/2009; 15:1764-73. · 2.20 Impact Factor
Dataset: Application of siRNA
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ABSTRACT: Although it is one of the major targeted organs by systemically administered siRNA, when compared to other tissues the kidney receives only moderate interest regarding therapeutic siRNA delivery. Here we review recent approaches to target renal protein expression under normal and pathological conditions. Experimental evidence to support the clinical relevance of siRNA administration in the treatment of renal disease is discussed. High-throughput screening using recently available genome-wide RNA interference libraries provides a new, powerful tool that can be applied to conventional and 3D in vitro culture models for lead finding or the identification of signal pathway involvement in renal disease.Advanced drug delivery reviews 11/2010; 62(14):1378-89. · 11.96 Impact Factor