Altered microRNA expression profiles in a rat model of spina bifida

Micro RNAs（mi RNAs） are dynamically regulated during neurodevelopment,yet few reports have examined their role in spina bifida.In this study,we used an established fetal rat model of spina bifida induced by intragastrically administering olive oil-containing all-trans retinoic acid to dams on day 10 of pregnancy.Dams that received intragastric administration of all-trans retinoic acid-free olive oil served as controls.The mi RNA expression profile in the amniotic fluid of rats at 20 days of pregnancy was analyzed using an mi RNA microarray assay.Compared with that in control fetuses,the expression of mi RNA-9,mi RNA-124 a,and mi RNA-138 was significantly decreased（〉 2-fold）,whereas the expression of mi RNA-134 was significantly increased（〉 4-fold） in the amniotic fluid of rats with fetuses modeling spina bifida.These results were validated using real-time quantitative reverse-transcription polymerase chain reaction.Hierarchical clustering analysis of the microarray data showed that these differentially expressed mi RNAs could distinguish fetuses modeling spina bifida from control fetuses.Our bioinformatics analysis suggested that these differentially expressed mi RNAs were associated with many cytological pathways,including a nervous system development signaling pathway.These findings indicate that further studies are warranted examining the role of mi RNAs through their regulation of a variety of cell functional pathways in the pathogenesis of spina bifida.Such studies may provide novel targets for the early diagnosis and treatment of spina bifida.

Effect of electroacupuncture on the mRNA and protein expression of Rho-A and Rho-associated kinase Ⅱ in spinal cord injury rats

Electroacupuncture is beneficial for the recovery of spinal cord injury, but the underlying mechanism is unclear. The Rho/Rho-associated kinase（ROCK） signaling pathway regulates the actin cytoskeleton by controlling the adhesive and migratory behaviors of cells that could inhibit neurite regrowth after neural injury and consequently hinder the recovery from spinal cord injury. Therefore, we hypothesized electroacupuncture could affect the Rho/ROCK signaling pathway to promote the recovery of spinal cord injury. In our experiments, the spinal cord injury in adult Sprague-Dawley rats was caused by an impact device. Those rats were subjected to electroacupuncture at Yaoyangguan（GV3）, Dazhui（GV14）, Zusanli（ST36） and Ciliao（BL32） and/or monosialoganglioside treatment. Behavioral scores revealed that the hindlimb motor functions improved with those treatments. Real-time quantitative polymerase chain reaction, fluorescence in situ hybridization and western blot assay showed that electroacupuncture suppressed the m RNA and protein expression of Rho-A and Rho-associated kinase Ⅱ（ROCKⅡ） of injured spinal cord. Although monosialoganglioside promoted the recovery of hindlimb motor function, monosialoganglioside did not affect the expression of Rho-A and ROCKⅡ. However, electroacupuncture combined with monosialoganglioside did not further improve the motor function or suppress the expression of Rho-A and ROCKⅡ. Our data suggested that the electroacupuncture could specifically inhibit the activation of the Rho/ROCK signaling pathway thus partially contributing to the repair of injured spinal cord. Monosialoganglioside could promote the motor function but did not suppress expression of Rho A and ROCKⅡ. There was no synergistic effect of electroacupuncture combined with monosialoganglioside.