Stronger expression of CHOP and caspase 12 in diabetic spinal cord injury rats.
OBJECTIVE
It is suggested that the injury-induced cell death of neurons within the spinal cord is related with endoplasmic reticulum (ER) stress. In this work, we explored that diabetes induce more severe spinal cord injury (SCI) and stronger ER stress in rats.


METHODS
Forty-five Sprague-Dawley rats were divided into three groups at random (the sham operation control group, SCI group and diabetic SCI group). Streptozotocin was injected into the caudal vein (30 mg/kg) to induce diabetes; 4 weeks after diabetes model induction, using a weight-drop contusion model of SCI in SCI group and diabetic SCI group; then, rats were killed at 24 hours and 7 days, and the level of C/EBP homologous transcription factor protein (CHOP), a proapoptotic protein, and caspase 12 were determined by immunohistochemistry staining and real-time reverse transcription quantitative polymerase chain reaction analysis.


RESULTS
We observe that both CHOP and caspase 12 were higher in diabetic SCI group than in the SCI group. Diabetes also caused severe locomotor dysfunction and slowly recovered as their Basso, Beattie and Bresnaha scores lowered. Pathological hematoxylin-eosin staining observation also showed progressive disruption of the dorsal white and few neurons regeneration in diabetic SCI rats.


CONCLUSIONS
These results suggest that stronger ER stress in diabetic rats may be the reason for severe SCI observed.
Wan
Shuanglin
S
Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
Shi
Peihua
P
Zhang
Xiaoming
X
Gu
Chuanlong
C
Fan
Shunwu
S
D000704:Analysis of Variance; D000818:Animals; D053454:Caspase 12 / Q000235:genetics / Q000378:metabolism*; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism* / Q000473:pathology; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D008297:Male; D009043:Motor Activity; D009474:Neurons / Q000378:metabolism / Q000473:pathology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013116:Spinal Cord / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D013119:Spinal Cord Injuries / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D013194:Staining and Labeling; D013311:Streptozocin / Q000494:pharmacology; D051742:Transcription Factor CHOP / Q000235:genetics / Q000378:metabolism*
D012333:RNA, Messenger; D051742:Transcription Factor CHOP; D013311:Streptozocin; D053454:Caspase 12