Laboratory Research
Ethyl pyruvate reduces spinal cord edema after spinal cord injury and attenuates spinal cord astrocyte swelling and aquaporin-4 expression after oxygen-glucose deprivation and reoxygenation in vitro by inhibiting high mobility group box-1 in rats
Sun Lin, Ma Xun, Liu Qiang, Feng Haoyu, Huo Jianzhong, Song Junlai, Lyv Cong
Published 2018-12-15
Cite as Chin J Orthop Trauma, 2018,20(12): 1079-1086. DOI: 10.3760/cma.j.issn.1671-7600.2018.12.012
Abstract
ObjectiveTo study the roles of ethyl pyruvate (EP) in spinal cord edema after spinal cord injury (SCI) and in spinal cord astrocytic swelling after oxygen-glucose deprivation and reoxygenation (OGD/R) in vitro in rats.
MethodsAfter SCI models were established in adult Sprague-Dawley (SD) rats, an intraperitoneal injection of EP was conducted to inhibit high mobility group box-1 (HMGB1). Effects of EP on spinal cord edema, HMGB1 expression and astrocyte activation (glial fibrillary acidic protein (GFAP) expression) in SCI rats were analyzed. Spinal cord astrocytes were cultured in post-natal SD rats and incubated under OGD/R procedure. Effects of EP on cell swelling, expression of HMGB1, aquaporin-4 (AQP4) and toll-like receptor 4 (TLR4), and nuclear expression of nuclear factor-kappa B (NF-κB) in spinal cord astrocytes were observed.
ResultsThe water content in the spinal cord was increased significantly more at 1 d after SCI than at 12 h and 3 d (P<0.05). Intraperitoneal injection of EP at 50 mg/kg reduced spinal cord water content, HMGB1 expression and astrocyte activation (GFAP expression) in SCI rats significantly more than that at 25 mg/kg or 100 mg/kg (P<0.05). The volume of spinal cord astrocytes cultured in vitro after OGD 6 h/R 24 h was significantly greater than that after OGD 6 h/R 6 h or OGD 6 h/R 12 h (P<0.05). EP at 12 μmol/L reduced cell swelling, decreased expression of HMGB1, AQP4 and TLR4, and downgraded nuclear expression of NF-κB in spinal cord astrocytes after OGD/R significantly more than EP at 6 μmol/L(P<0.05).
ConclusionEP may reduce early spinal cord edema after SCI, attenuate spinal cord astrocyte swelling and decrease AQP4 expression after OGD/R in vitro by inhibiting HMGB1 in rats.
Key words:
Spinal cord injury; Astrocyte; Ethyl pyruvate; High mobility group box-1; Aquaporin-4
Contributor Information
Sun Lin
Department of Orthopedics, Shanxi Academy of Medical Sciences, Shanxi Da Yi Hospital Affiliated to Shanxi Medical University, Taiyuan 030032, China
Ma Xun
Liu Qiang
Feng Haoyu
Huo Jianzhong
Song Junlai
Lyv Cong