Micro Ran ppt rob ucla

MicroRNA

MicroRNA Overview• Small non-coding ssRNA (~22nts) that negatively regulate gene

expression by binding to 3’-UTR region and inhibiting translation or inducing degradation of mRNA

• Involved in the fine tuning of many processes including cell proliferation, differentiation, and cell death.

• Play important role in pathogenesis of several human diseases.

MicroRNA-210• Upregulated in response to hypoxia induces angiogenesis

• Overexpression stimulates formation of capillary-like structures in vitro in normoxic conditions and VEGF-driven cell migration

• Several studies out of Japan have demonstrated that direct administration of synthetic MicroRNA-210 can enhance the healing of the ACL, Meniscus, and Achilles tendon via upregulation of VEGF, bFGF, and Collagen production.

Effect on Ligament Healing Hypothesized that miRNA-210 administration would augment healing of the ACL after partial transection by accelerating angiogenesis.

Shoji T, Nakasa T, Yamasaki K, et al. The effect of intra-articular injection of microRNA-210 on ligament healing in a rat model. Am J Sports Med. 2012; 40(11):2470-8.

Effect on Ligament Healing 1. Temporal expression pattern of miR-210 after partial transection of the

ACL:

• Initial downregulation soon after injury with gradual upregulation thereafter• 3x increase between Day 0 and Week 4


Effect on Ligament Healing 2. Effect of intra-articular injection of miR-210 on ligament healing after

-injected 30uL miR210-Atelocollagen complex (20ug/15uL) directly into the knee joint immediately after transection

3. Results:• ↑ miR-210, VEGF, FGF2, COL1 Expression• ↑ # of blood vessels• ↑ ultimate load to failure at 4 weeks


partial transection of the ACL:

Effect on Ligament Healing 3. Results:• ↑ miR-210, VEGF, FGF2, COL1 Expression• ↑ # of blood vessels


Effect on Ligament Healing 3. Results:• ↑ miR-210, VEGF, FGF2, COL1 Expression• ↑ # of blood vessels• ↑ ultimate load to failure at 4 weeks

- 30.5 ± 3.1 N vs 22.8 ± 3.1 N


Effect on Ligament Healing 3. Results:• ↑ miR-210, VEGF, FGF2, COL1 Expression• ↑ # of blood vessels• ↑ ultimate load to failure at 4 weeks• Histology:


Meniscal Healing• In vitro• ↑ VEGF, FGF2 production by synovial cells• ↑ COL2a1 expression by meniscal cells

• In Vivo• 4 weeks: Defect was filled and repaired; Increase in # of blood vessels • 12 weeks: Injured site was healed and less articular cartilage degeneration

Kawanishi Y, Nakasa T, Shoji T, et al. Intra-articular injection of synthetic microRNA-210 accelerates avascular meniscalhealing in rat medial meniscal injured model. Arthritis Res Ther. 2014;16(6):488.

Achilles Tendon Healing• Completely transected and repaired Achilles tendons followed by

injection of ds microRNA-210• Regular, dense collagen with a larger fiber diameter at 2 & 6 weeks• Parallel/dense fibers vs wavy/loose at 12 weeks• ↑ VEGF, FGF2, COL1 Expression at 2 weeks• ↑ ultimate load to failure at 2 weeks• Abundant Vessels at 2 weeks, no significant difference at 6 weeks

Usman MA, Nakasa T, Shoji T, et al. The effect of administration of double stranded MicroRNA-210 on acceleration of Achilles tendon healing in a rat model. J Orthop Sci. 2015;20(3):538-46..

miRNA-210 coated UHMW Scaffold Studies

• Augmentation of ligament healing via MicroRNA coated UHMW PCL scaffold

• Providing structural integrity while allowing for a targeted, controlled, and sustained delivery of MicroRNA

Micro Ran ppt rob ucla

Documents

Transcript of Micro Ran ppt rob ucla