Administration of low dose estrogen attenuates gliosis and protects neurons in acute spinal cord injury in rats

作者:Samantaray Supriti; Das Arabinda; Matzelle Denise C; Yu Shan P; Wei Ling; Varma Abhay; Ray Swapan K; Banik Naren L
来源:Journal of Neurochemistry, 2016, 136(5): 1064-1073.
DOI:10.1111/jnc.13464

摘要

Spinal cord injury (SCI) is a debilitating condition with neurological deficits and loss of motor function that, depending on the severity, may lead to paralysis. The only treatment currently available is methylprednisolone, which is widely used and renders limited efficacy in SCI. Therefore, other therapeutic agents must be developed. The neuroprotective efficacy of estrogen in SCI was studied with a pre-clinical and pro-translational perspective. Acute SCI was induced in rats that were treated with low doses of estrogen (1, 5, 10, or 100g/kg) and compared with vehicle-treated injured rats or laminectomy control (sham) rats at 48h post-SCI. Changes in gliosis and other pro-inflammatory responses, expression and activity of proteolytic enzymes (e.g., calpain, caspase-3), apoptosis of neurons in SCI, and cell death were monitored via Western blotting and immunohistochemistry. Negligible pro-inflammatory responses or proteolytic events and very low levels of neuronal death were found in sham rats. In contrast, vehicle-treated SCI rats showed profound pro-inflammatory responses with reactive gliosis, elevated expression and activity of calpain and caspase-3, elevated Bax:Bcl-2 ratio, and high levels of neuronal death in lesion and caudal regions of the injured spinal cord. Estrogen treatment at each dose reduced pro-inflammatory and proteolytic activities and protected neurons in the caudal penumbra in acute SCI. Estrogen treatment at 10g was found to be as effective as 100g in ameliorating the above parameters in injured animals. Results from this investigation indicated that estrogen at a low dose could be a promising therapeutic agent for treating acute SCI.

  • 出版日期2016-3