Loss of micro RNA-124 expression in neurons in the peri-lesion area in mice with spinal cord injury

Micro RNA-124（mi R-124） is abundantly expressed in neurons in the mammalian central nervous system, and plays critical roles in the regulation of gene expression during embryonic neurogenesis and postnatal neural differentiation. However, the expression profile of mi R-124 after spinal cord injury and the underlying regulatory mechanisms are not well understood. In the present study, we examined the expression of mi R-124 in mouse brain and spinal cord after spinal cord injury using in situ hybridization. Furthermore, the expression of mi R-124 was examined with quantitative RT-PCR at 1, 3 and 7 days after spinal cord injury. The mi R-124 expression in neurons at the site of injury was evaluated by in situ hybridization combined with Neu N immunohistochemical staining. The mi R-124 was mainly expressed in neurons throughout the brain and spinal cord. The expression of mi R-124 in neurons significantly decreased within 7 days after spinal cord injury. Some of the neurons in the peri-lesion area were Neu N＋/mi R-124-. Moreover, the neurons distal to the peri-lesion site were Neu N＋/mi R-124＋. These findings indicate that mi R-124 expression in neurons is reduced after spinal cord injury, and may reflect the severity of spinal cord injury.

Protective Effects of Radix Astragali Injection on Multiple Organs of Rats with Obstructive Jaundice

Objective： To investigate the protective effects and mechanisms of Radix Astragali Injection on multiple organs of rats with obstructive jaundice（OJ）. Methods： A total of 180 rats were randomly divided into the sham-operated, model control and treated groups（60 in each group）. On 7, 14, 21 and 28 days after operation, the serum contents of alanine aminotransferase（ALT）, aspartate aminotransferase（AST）, r-glutamyl transpeptidase（r-GT）, total bilirubin（TBil）, direct bilirubin（DBil）, blood urine nitrogen（BUN）, and creatinine（CREA） were determined. And the pathological changes of livers, kidneys and lungs, and protein expressions of toll-like receptor-4（TLR-4） of livers, intercellular adhesion molecule-1（ICAM-1） of lungs, Bax and nuclear factor-kappa B（NF-κB）, as well as apoptotic indexes of multiple organs were observed, respectively. Results： The pathological severity scores of multiple organs（including livers on 7, 14, 21 and 28 days, kidneys on 14 and 28 days, and lungs on 14 days）, serum contents of ALT（14 and 21 days）, AST（14 days）, TBil（7, 14, 21 and 28 days）, DBil（14 and 21 days）, BUN（28 days）, protein expressions of TLR-4（in livers, 28 days）, Bax（in livers and kidneys, 21 days）, and apoptotic indexes in livers（7 and 21 days） in the treated group were significantly lower than those in the model control group（P〈0.05 or P〈0.01）. Conclusion： Radix Astragali Injection exerts protective effects on multiple organs of OJ rats by improving the pathological changes of lung, liver and kidney, decreasing the serum index of hepatic and renal function as well as inhibiting the protein expression of TLR-4 and Bax in the livers and Bax in the kidneys.