Targeted SiRNA Delivery Reduces Nitric Oxide Mediated Cell Death After Spinal Cord Injury

Overview

Journal J Nanobiotechnology

Publisher Biomed Central

Specialty Biotechnology

Date 2017 May 10

PMID 28482882

Citations 18

Authors

Wen Gao

Jianming Li

Affiliations

Soon will be listed here.

Abstract

Background: Traumatic spinal cord injury (SCI) includes the primary insult as well as a sequela of biochemical and cellular cascades that amplifies the initial injury. This degenerative process, known as secondary injury, is often mediated by both reactive oxygen and nitrogen species released from damaged cells. Previous data suggests that dysregulated production of nitric oxide via inducible nitric oxide synthase (iNOS) is detrimental to spinal cord recovery. M1 macrophages have been implicated to overexpress iNOS post-SCI. In this work, we propose to inhibit iNOS expression through small interfering RNA (siRNA) complexed chitosan nanoparticles (NPs) that primarily target M1 macrophages.

Methods: siRNA conjugated chitosan complexes were fabricated with and without an antibody (Ab) targeting moiety and screened for efficiency to reduce iNOS expression in vitro. Best formulations were subsequently applied in vivo following acute SCI in a rodent model. iNOS expression as well as Bax and Bcl-2 biomarkers were used to assess cell apoptosis within the lesion at 24 h post-injury.

Results: Ab-siRNA conjugated chitosan NPs significantly reduced iNOS expression in vitro in M1 polarized macrophages. Results show high transfection efficiency with low cytotoxicity. Subsequent application of NPs in vivo after SCI demonstrated both a reduction in iNOS expression and cellular apoptosis.

Conclusion: Proof of concept indicates that siRNA conjugated chitosan NPs can downregulate iNOS production and inhibit apoptosis following SCI. Our proposed gene silencing method putatively targets M1 macrophages as a means to attenuate secondary injury.

Citing Articles

Advancements in Antioxidant-Based Therapeutics for Spinal Cord Injury: A Critical Review of Strategies and Combination Approaches.

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Saha P, Sharma S ACS Pharmacol Transl Sci. 2024; 7(10):2951-2970.

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Gao X, Jin B, Zhou X, Bai J, Zhong H, Zhao K J Nanobiotechnology. 2024; 22(1):277.

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Neurotrauma-From Injury to Repair: Clinical Perspectives, Cellular Mechanisms and Promoting Regeneration of the Injured Brain and Spinal Cord.

Stevens A, Belli A, Ahmed Z Biomedicines. 2024; 12(3).

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α-Gal Nanoparticles in CNS Trauma: II. Immunomodulation Following Spinal Cord Injury (SCI) Improves Functional Outcomes.

Gopalakrishnan B, Galili U, Saenger M, Burket N, Koss W, Lokender M Tissue Eng Regen Med. 2024; 21(3):437-453.

PMID: 38308742 PMC: 10987462. DOI: 10.1007/s13770-023-00616-y.

References

Bernkop-Schnurch A, Dunnhaupt S . Chitosan-based drug delivery systems. Eur J Pharm Biopharm. 2012; 81(3):463-9. DOI: 10.1016/j.ejpb.2012.04.007. View

McWhorter F, Wang T, Nguyen P, Chung T, Liu W . Modulation of macrophage phenotype by cell shape. Proc Natl Acad Sci U S A. 2013; 110(43):17253-8. PMC: 3808615. DOI: 10.1073/pnas.1308887110. View

Yang Y, Liu Y, Wei P, Peng H, Winger R, Hussain R . Silencing Nogo-A promotes functional recovery in demyelinating disease. Ann Neurol. 2010; 67(4):498-507. PMC: 2929680. DOI: 10.1002/ana.21935. View

Liu D, Ling X, Wen J, Liu J . The role of reactive nitrogen species in secondary spinal cord injury: formation of nitric oxide, peroxynitrite, and nitrated protein. J Neurochem. 2000; 75(5):2144-54. DOI: 10.1046/j.1471-4159.2000.0752144.x. View

Resnier P, Montier T, Mathieu V, Benoit J, Passirani C . A review of the current status of siRNA nanomedicines in the treatment of cancer. Biomaterials. 2013; 34(27):6429-43. DOI: 10.1016/j.biomaterials.2013.04.060. View

Oh Y, Park T . siRNA delivery systems for cancer treatment. Adv Drug Deliv Rev. 2009; 61(10):850-62. DOI: 10.1016/j.addr.2009.04.018. View

Oltvai Z, Milliman C, Korsmeyer S . Bcl-2 heterodimerizes in vivo with a conserved homolog, Bax, that accelerates programmed cell death. Cell. 1993; 74(4):609-19. DOI: 10.1016/0092-8674(93)90509-o. View

David S, Kroner A . Repertoire of microglial and macrophage responses after spinal cord injury. Nat Rev Neurosci. 2011; 12(7):388-99. DOI: 10.1038/nrn3053. View

Xiong Y, Rabchevsky A, Hall E . Role of peroxynitrite in secondary oxidative damage after spinal cord injury. J Neurochem. 2006; 100(3):639-49. DOI: 10.1111/j.1471-4159.2006.04312.x. View

10.

Kong X, Gao J . Macrophage polarization: a key event in the secondary phase of acute spinal cord injury. J Cell Mol Med. 2016; 21(5):941-954. PMC: 5387136. DOI: 10.1111/jcmm.13034. View

11.

Kong Q, Lin C . Oxidative damage to RNA: mechanisms, consequences, and diseases. Cell Mol Life Sci. 2010; 67(11):1817-29. PMC: 3010397. DOI: 10.1007/s00018-010-0277-y. View

12.

Kigerl K, Gensel J, Ankeny D, Alexander J, Donnelly D, Popovich P . Identification of two distinct macrophage subsets with divergent effects causing either neurotoxicity or regeneration in the injured mouse spinal cord. J Neurosci. 2009; 29(43):13435-44. PMC: 2788152. DOI: 10.1523/JNEUROSCI.3257-09.2009. View

13.

He C, Hu Y, Yin L, Tang C, Yin C . Effects of particle size and surface charge on cellular uptake and biodistribution of polymeric nanoparticles. Biomaterials. 2010; 31(13):3657-66. DOI: 10.1016/j.biomaterials.2010.01.065. View

14.

Hall E . Antioxidant therapies for acute spinal cord injury. Neurotherapeutics. 2011; 8(2):152-67. PMC: 3101837. DOI: 10.1007/s13311-011-0026-4. View

15.

Liu X, Howard K, Dong M, Andersen M, Rahbek U, Johnsen M . The influence of polymeric properties on chitosan/siRNA nanoparticle formulation and gene silencing. Biomaterials. 2006; 28(6):1280-8. DOI: 10.1016/j.biomaterials.2006.11.004. View

16.

Isaksson J, Farooque M, Olsson Y . Improved functional outcome after spinal cord injury in iNOS-deficient mice. Spinal Cord. 2004; 43(3):167-70. DOI: 10.1038/sj.sc.3101672. View

17.

Williford J, Wu J, Ren Y, Archang M, Leong K, Mao H . Recent advances in nanoparticle-mediated siRNA delivery. Annu Rev Biomed Eng. 2014; 16:347-70. DOI: 10.1146/annurev-bioeng-071813-105119. View

18.

Qie Y, Yuan H, von Roemeling C, Chen Y, Liu X, Shih K . Surface modification of nanoparticles enables selective evasion of phagocytic clearance by distinct macrophage phenotypes. Sci Rep. 2016; 6:26269. PMC: 4872535. DOI: 10.1038/srep26269. View

19.

Bumcrot D, Manoharan M, Koteliansky V, Sah D . RNAi therapeutics: a potential new class of pharmaceutical drugs. Nat Chem Biol. 2006; 2(12):711-9. PMC: 7097247. DOI: 10.1038/nchembio839. View

20.

Gilberti R, Joshi G, Knecht D . The phagocytosis of crystalline silica particles by macrophages. Am J Respir Cell Mol Biol. 2008; 39(5):619-27. PMC: 2574531. DOI: 10.1165/rcmb.2008-0046OC. View