Tetramethylpyrazine Accelerated Spinal Cord Repair Through Regulation Of PGC-1α And ERR-α Expression:an Acute Spinal Cord Injury Model In Rats

OBJECTIVE These studies intend to detect the changes of PGC-1α/ERR-α expression after ASCI and the influence that Tetrame-thylpyrazine treat on them, and to explore the specific mechanisms of Tetramethylpyrazine protect spinal cord function.METHODS54adult male Sprague Dawley rats were randomly divided into three groups:(a) sham operation group (group Sham, n=6);(b) normal saline group (group NS, n=24);(c). Tetramethylpyrazine group (group TMP, n=24). Group b and c rats use a modified Allen's weight drop method to make an acute spinal cord injury model. Rats of group Sham simply take a laminectomy;30min after the operation, group TMP take a intraperitoneal injection of tetramethylpyrazine,200mg/kg,1time per day for5day. Group Sham and group NS injection2ml saline. Group TMP and group NS are divided into1day,3days,7days,14days,21days,28days, a total of six subgroups. At the time points after the injury, collect the spinal cord tissue samples from the injured segment with the length of5mm (T10segment). The sham operation group to take one and other12subgroups each take one, total of13specimen, the13specimens were used for HE staining to detect the recovery situations of spinal cord injury. Residual spinal cord tissue extract total protein and Western-Blot of PGC-1α and ERR-α expression levels. Using Image J image analysis stripe absorbance. The measurement results x±s. Software SPSS10.0was applied to analysis if there was significant difference between the two related groups at each time point.RESULTS (1) HE staining shows damage in the spinal cord undergo extensive bleeding, hematoma formation, hematoma absorption, collagen proliferation, scar formation and other pathological process.(2) PGC-1α expression:Compared with group Sham, expression of group NS significantly improve at1st day (P<0.01). At the3rd day,7th day, PGC-1α expression also improve (0.01<P<0.05). At the14th day,21st day,28th day, PGC-1α expression in the NS group and the Sham group was no significant difference (P>0.05).Compared with group Sham, expression of group TMP significantly improve at1st day,3rd day,7th day,14th day (P<0.01). At the21st day, PGC-la expression was also improved (0.01<P<0.05). At the28th day, PGC-la expression in group TMP and group Sham has no significant difference (P>0.05).Compared with group NS, expression of group TMP significantly higher at the3rd day,7th day,14th day (P<0.01). At the21st day, PGC-1α expression was also improved (0.01<P<0.05). At the1st day,28th day, PGC-1α expression in group TMP and group NS has no significant difference (P>0.05).(3) ERR-a expression:Compared with group Sham, the ERR-a expression of group NS has no significant difference at all time points (P>0.05).Compared with group Sham, expression of group TMP significantly higher at the7th days14th days (P<0.01). At the1st day,3rd day,21st day,28th day, the ERR-a expression in group TMP and group Sham has no significant difference (P>0.05).Compared with group NS, expression of group TMP significantly higher at the7th days14th days (P<0.01). At the1st day,3rd day,21st day,28th day, the ERR-a expression in group TMP and group Sham has no significant difference (P>0.05).CONCULUSION PGC-la/ERR-a mediated hypoxia regulation mechanism also exists in spinal cord injury. Increase PGC-la/ERR-a pathway expression may be one of the mechanisms that Tetramethylp-yrazine improve the microcirculation after SCI.