The double-stranded miR-29 mimics design contains a “guide strand” or “antisense strand” that is identical to the miR-29b, with a UU overhang on the 3′ end, modified to increase stability, and chemically phosphorylated on the 5′ end and a “passenger strand” or “sense strand” that contains 2′-O-Me modifications to prevent loading into RNA-induced silencing complex (RISC) as well as increase stability and is linked to cholesterol for enhanced cellular uptake. Several mismatches are introduced in the sense strand to prevent this strand from functioning as an antimiR.
Transfection experiments in NIH 3T3 show a dose-dependent decrease in Col1a1 with increasing amount of miR-29b mimic compared to either untreated or mock-treated cells. An siRNA directly targeting Col1a1 was taken along as a positive control. *P < 0.05 versus mock, #P < 0.05 versus untreated.
Northern blot analysis for miR-29b in different tissues 4 days after intravenous injection with 10, 50, 100, or 125 mpk miR-29b mimic indicates delivery to all tissues at the highest dose, with the most effective delivery taking place to the lungs and spleen compared to saline-injected mice. U6 is used as a loading control.
Real-time quantification of miR-29b mimicry indicates an increased level of miR-29b at the higher dose levels with the most efficient delivery to the lungs and spleen (n = 4 per group). *P < 0.05 versus saline-injected animals.
Northern blot analysis for miR-29b in different tissues 1, 2, 4, and 7 days after intravenous injection with 125 mpk of mimic indicates the presence of miR-29b mimic in all tissues examined, with a longer detection in lung and spleen. U6 is used as a loading control.
Real-time quantification of miR-29b mimicry indicates an increased level of miR-29b in all tissues measured which is maintained the longest in lungs and spleen (n = 4 per group). *P < 0.05 versus saline-injected animals.
