Although better understanding of spinal cord injury (SCI) and its underlying mechanisms has been achieved, creating an effective therapy is still unrealized. Inflammation, intracellular Ca2+ influx, and oxidative damage are implicit in the initiation of secondary injury pathways leading to cell death following SCI. Since the only currently available treatment, methylprednisolone, has limited clinical efficacy, novel therapies to block inflammation, reduce cell and axon-myelin damage, and restore blood supply must be discovered. Neuroprotection has been achieved in acute SCI with a low dose of the multi-active agent estrogen. Estrogen suppresses Ca2+ influx and inflammation in SCI and cultured cells by blocking L-type Ca2+ channels. Preliminary data indicates that low dose estrogen reduces inflammation, inhibits calpain-caspase activity, protects cells, preserves axons and myelin, and restores locomotor function. These results indicate that estrogen may be used as a therapeutic agent for treatment of SCI. By understanding SCI pathophysiology, therapies with low dose estrogen (17-estradiol), alone or in combination, will be designed to prevent inflammation, axonal damage, and cell death in the spinal cord after injury. Because multiple pathways cause tissue destruction in SCI, blocking only one pathway may not be optimal. The goal of this proposal is to protect CNS cells and the axon-myelin unit from secondary damage by utilizing estrogen treatment and also by combining agents that preserve tissue and promote greater functional recovery. In addition to estrogen, treatment with angiogenesis-promoting factors, e.g. vascular endothelial growth factor (VEGF), will further increase the blood supply to the injured cord and aid in functional recovery. We hypothesize that estrogen will promote vascular growth, prevent Ca2+ influx, and attenuate cell and axon-myelin damage, lipid peroxidation, inflammation, and monocyte phagocytosis. Inhibition of these pathways will consequently block downstream calpain-mediated apoptotic events. Combination therapy with VEGF will further promote recovery by restoring tissue perfusion.
Three specific aims will test the hypothesis: (1) investigate whether low dose estrogen therapy will preserve motor function following SCI by reducing inflammation and axonal damage, and protecting neuronal and glial cells from apoptotic events; (2) determine whether single therapy with low-dose estrogen or combination therapy with the angiogenic factor VEGF will further improve motor function long-term following SCI by promoting angiogenesis; and (3) examine the mechanisms of neuroprotection mediated by estrogen +/- VEGF in neurons and glia subjected to either excitotoxic or inflammatory stress. Results obtained from the proposed studies will have strong translational application to SCI, suggesting estrogen's therapeutic significance.
Because methylprednisolone has limited benefit in the treatment of spinal cord injury (SCI), this study will examine the efficacy of multi-active estrogen as a therapeutic agent alone as well as in a combination of angiogenic factors. Studies are focused on determining the most effective low dose of estrogen and vascular endothelial growth factor (VEGF) that protects cells and whether the combination treatment will increase blood supply and microvessel growth, leading to recovery of locomotor function in chronic SCI. Regulation of calcium-mediated events, protection of cells and axon-myelin integrity, and restoration of blood supply to the injured cord by this therapy may be crucial to treatment of human SCI.
|Trager, Nicole N M; Butler, Jonathan T; Harmon, Jennifer et al. (2018) A Novel Aza-MBP Altered Peptide Ligand for the Treatment of Experimental Autoimmune Encephalomyelitis. Mol Neurobiol 55:267-275|
|Haque, Azizul; Capone, Mollie; Matzelle, Denise et al. (2017) Targeting Enolase in Reducing Secondary Damage in Acute Spinal Cord Injury in Rats. Neurochem Res 42:2777-2787|
|Samantaray, Supriti; Das, Arabinda; Matzelle, Denise C et al. (2016) Administration of low dose estrogen attenuates persistent inflammation, promotes angiogenesis, and improves locomotor function following chronic spinal cord injury in rats. J Neurochem 137:604-17|
|Samantaray, Supriti; Das, Arabinda; Matzelle, Denise C et al. (2016) Administration of low dose estrogen attenuates gliosis and protects neurons in acute spinal cord injury in rats. J Neurochem 136:1064-73|
|Cox, April; Varma, Abhay; Banik, Naren (2015) Recent advances in the pharmacologic treatment of spinal cord injury. Metab Brain Dis 30:473-82|
|Lee, Philip; Murphy, Ben; Miller, Rickey et al. (2015) Mechanisms and clinical significance of histone deacetylase inhibitors: epigenetic glioblastoma therapy. Anticancer Res 35:615-25|
|Samantaray, Supriti; Knaryan, Varduhi H; Shields, Donald C et al. (2015) Inhibition of Calpain Activation Protects MPTP-Induced Nigral and Spinal Cord Neurodegeneration, Reduces Inflammation, and Improves Gait Dynamics in Mice. Mol Neurobiol 52:1054-66|
|Samantaray, Supriti; Knaryan, Varduhi H; Patel, Kaushal S et al. (2015) Chronic intermittent ethanol induced axon and myelin degeneration is attenuated by calpain inhibition. Brain Res 1622:7-21|
|Agrawal, Neena Stephanie; Miller Jr, Rickey; Lal, Richa et al. (2014) Current Studies of Immunotherapy on Glioblastoma. J Neurol Neurosurg 1:|
|Chakrabarti, M; Banik, N L; Ray, S K (2014) MiR-7-1 potentiated estrogen receptor agonists for functional neuroprotection in VSC4.1 motoneurons. Neuroscience 256:322-33|
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