ABSTRACT
Objective Polyinosinic-polycytidylic acid (poly IC) plays an important role in the central nervous system damage and repair.This study was to investigate the effect of poly IC on inflammatory response after spinal cord ischemia-reperfusion injury (SCIRI) in rats.Methods A total of 72 healthy adult male SD rats were equally randomized into a sham-operation, an ischemia-reperfusion (IR), and a poly IC group.The abdominal cavities of the rats were cut open and closed again in the sham-operation group and SCIRI models were established in the IR and poly IC groups by clamping the abdominal aorta, followed by reperfusion 60 minutes later and intraperitoneal injection of saline (0.1 mL) and poly IC (1.25 μg/g), respectively.At 6, 24, and 48 hours after modeling, BBB scores were obtained and the contents of TNFα, IL-1β and IFN-β were measured by ELISA.At 48 hours, the expressions of NF-κB and IL-10 were determined by immunohistochemistry, the area of ischemic necrosis in the spinal cord tissue was calculated by TTC staining, and its morphological changes were observed under the optical microscope.Results At 48 hours after modeling, the BBB scores were significantly lower in the IR and poly IC groups than in the sham-operation group (3.80±0.75 and 9.40±0.49 vs 20.00±0.00, P<0.01), though higher in the poly IC than in the IR group (P<0.01).The rats of the IR group showed extensive degenerated neurons in the gray substance of the spinal cord, with scattered foci of bleeding and blood coagulation, while those of the poly IC group exhibited fewer necrotic neurons and basically normal nuclear morphology, though with a few swelling cells.The ischemic necrosis area of the spinal cord tissue was significantly reduced.The expression of NF-κB was decreased while that of IL-10 increased markedly.Compared with the IR group, the poly IC group showed a significant increase in the expression of IFNβ (117.23±6.06 vs 55.65±4.02, P<0.01) and a remarkably decrease in the expressions of TNFα (190.45±4.16 vs 201.82±2.18, P<0.01) and IL-1β (39.27±2.48 vs 50.59±1.47, P<0.01) at 48 hours.Conclusion Poly IC can protect the spinal cord and reduce inflammatory response after spinal cord ischemia-reperfusion injury.
ABSTRACT
Objective To observe the mechanisms of bone marrow mesenchymal stem cells (BMSCs) transfected with neurotrophin-3 in treating nanoparticle repaired spinal cord ischemia-reperfusion (I/R) injury of adult rat. Methods BMSCs were transfected into NT-3 with nanoparticle carrier and transplanted into 80 adult rats on the spinal cord I/R injury model. Then the rats were divided into four groups: sham group, NS group, BMSCs and BMSCs+NT-3. The BBB scoring system, the neurons cell apoptosis, levels of malondialdehyde (MDA) and myeloperoxidase (MPO) were observed and compared between the four groups. Results The BBB score of the BMSCs+NT-3 group was significantly higher than those of BMSCs and NS group , but was lower obviously than the Sham group. TUNEL-apoptosis cells were significantly decreased in the BMSCs + NT-3 group compared to BMSCs and NS groups, but was more significantly lower than the Sham group. The contents of MDA and MPO of the NS group were significantly higher than the BMSCs group. The contents of the BMSCs + NT-3 group were lower than those of the BMSCs group, but lower significantly than the Sham group (P < 0.05). Conclusion BMSCs transfected with NT-3 with nanoparticle carrier could be induced each other. When transplanted into SCI , they can repair spinal cord by alleviating neuron cells apoptosis and inhibiting the lipid peroxidation of free radicals.