ABSTRACT
ObjectiveTo explore the role of aryl hydrocarbon receptor/suppressor of cytokine signaling 2/nuclear transcription factor-κB (AHR/SOCS2/NF-κB) signaling in the reduction of spinal cord injury (SCI) inflammation with every-other-day fasting (EODF). MethodsA total of 36 healthy male Sprague-Dawley rats were randomly divided into sham group (n = 12), model group (n = 12) and EODF group (n = 12). The latter two groups were established C5 spinal cord hemi-clamp model. The EODF group received EODF, namely fasting and feeding per 24 hours (water free), for two weeks after operation. They were assessed with Grooming Test before operation, and one, seven and 14 days after operationt, respectively. Pathological injury of spinal cord was observed with HE staining 14 days after operation, while the expression of AHR, SOCS2 and NF-κB proteins were detected with Western blotting, and the mRNA of AHR, SOCS2, inhibitor α of NF-κB (IκBα), NF-κB and tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) were measured with reverse transcription real-time quantitative polymerase chain reaction. ResultsCompared with the sham group, the Grooming Test score decreased in the other two groups (P < 0.05), and cavity, edema and structural disorder appeared in the spinal cord. Compared with the model group, the pathology of EODF group improved, and the Grooming Test score increased (P < 0.05). The mRNA and protein expression of AHR and SOCS2 increased (P < 0.05), the mRNA and protein expression of NF-κB decreased (P < 0.05), the mRNA expression of IκBα increased (P < 0.05), and the mRNA expression of TNF-α and IL-6 decreased (P < 0.05). ConclusionEODF may promote the recovery of motor function of forelimb in rats with SCI, and relieve damage and inflammation, which may associate with the activation of AHR/SOCS2/NF-κB signaling pathway.
ABSTRACT
Objective To observe the effect of every-other-day fasting(EODF)on pathology and functional recovery of rats with spinal cord clip-compression injury,and to explore the related mechanism. Methods A total of 36 Sprague-Dawley rats were randomly assigned to groups A(sham operation),B(sham operation and EODF),C(spinal cord injury)and D(spinal cord injury and EODF)with nine rats in each group.The spinal cord injury rat model in T10was established by using medical aneurysm clip in latter two groups.The motor func-tion was assessed by Basso-Beattie-Bresnahan(BBB)score one day before and one day,two,four,six,eight,ten, twelve weeks after operation;and toluidine blue staining was performed for pathological observation at twelve weeks after operation.Another 180 Sprague-Dawley rats were randomly assigned in same way.The level of tu-mor necrosis factor-α(TNF-α)and interleukin-10(IL-10)were detected with ELISA six hours,twelve hours,one day,three days and seven days after operation. Results The BBB score reached lowest on the first day in groups C and D(P<0.05),and gradually increased with time,and were higher in group D than in group C eight weeks,ten weeks and twelve weeks after operation(P<0.05). The pathology in spinal cord was less in group D than in group C.Compared with group A,the level of serum TNF-α increased twelve hours after operation(P<0.05),peaked one day after operation,and returned back seven days after operation;the level of serum IL-10 increased at each time point after operation(P<0.05).Compared with group C,the level of serum TNF-α was lower in group D one day after operation(P<0.05);the level of se-rum IL-10 was not significantly different at each time point after operation(P>0.05). Conclusion Long-term EODF can promote the hind limb motor recovery in rats with spinal cord clip-compression inju-ry,and alleviate pathological damage.EODF might inhibit acute inflammatory reaction at acute stage of spinal cord injury,which may be correlated with its neuroprotective effect.