Identification of miR-126 knockdown mouse and the change of blood glucose / 中南大学学报(医学版)

OBJECTIVE@#To detect the expression of miR-126 in different tissues and organs and the change of peripheral blood glucose in microRNA-126 knock down (miR-126 KD) mouse, and to explore the pathological significance.@*METHODS@#Total RNAs were isolated from twelve kinds of tissues and organs in wild-type mouse (WT) and miR-126 KD mouse respectively. Th en, the expression level of miR-126 was detected by real-time PCR assay. Th e levels of peripheral blood glucose and body weight of miR-126 KD mice were measured. Th e pathologic changes of pancreas and lung tissue were observed by HE staining.@*RESULTS@#Compared with the WT mice, the relative expression of miR-126 in spleen, liver, muscle and lung from the miR-126 KD mice were dramatically decreased respectively (P<0.05). The level of peripheral blood glucose in the miR-126 KD mouse increased significantly at seven week and sixteen week after the birth (P<0.05). HE staining showed that the pathological structure of pancreas and liver were abnormal. The body weight of miR-126 KD mice was increased obviously from thirteen week after birth (P<0.05).@*CONCLUSION@#Peripheral blood glucose levels in the miR-126 KD mouse were dramatically elevated, which might be related to the pathological changes in the structure of pancreas and liver. These results suggest that miR-126 may play an important role in the metabolism of blood glucose and the development of type 2 diabetes mellitus.

Influence of microRNA-7 knock down on development of CD4+SP cells in murin-ethymus / 中国免疫学杂志

Objective:To investigate the influence of miR-7 knock down on the development of CD 4+SP cells in the thymus in mice,and preliminary explore its possible mechanism.Methods:The changes of volume ,weight and total cell counts of thymus in miR-7 knock down (miR-7KD) mice were observed compared with Wild-type(WT)mice;the pathological changes of thymus were observed by HE staining.FACS analysis was performed on the proportion ,as well as the expression level of CD44 and CD62L,of thymus CD4+single positive (SP) cells.Meanwhile,the proliferation percentage of CD4+SP cells was measured by Ki-67 staining.The apoptosis percentage of CD4+SP cells was analyzed by FACS.The changes on the transduction of ERK 1/2 pathways were determined by Western blot.Results:Compared with WT mice ,the size,weight and total cell number of thymus were marked reduced in miR-7KD mice( P<0.05 );moreover ,pathological change also was presented.The proportion and total cell number of thymus CD 4+SP cells were marked decreased ( P<0.05 ).Furthermore ,the expression level of CD 44 and proliferation percentage ,as well as apoptosis percentage ,of CD4+SP cells were obviously increased (P<0.05),however,the expression level of CD62L of CD4+SP cells were decreased (P<0.05). Finally,the level of total ERK1/2 and phosphor-ERK1/2 was decreased obviously ( P<0.05 ).Conclusion: miR-7 knock down can affect the development of CD 4+SP cells in the thymus , which might be closely related to the cell activation state and altered the transduction of ERK1/2 pathways.

Effect of microRNA-7 onαβT lymphocytes of mouse mesenteric lymph nodes / 中国免疫学杂志

Objective:To detect the change of proportions of αβT lymphocytes in mesenteric lymph nodes of miR-7 knockdown (miR-7KD)mice,and preliminarily explore its importance.Methods: The volume,weight index and total cells number of mesenteric lymph node in miR-7KD mice were measured.The pathologic morphology change of mesenteric lymph nodes was observed by HE stai -ning.And the changes on proportion of αβT lymphocytes in mesenteric lymph nodes of miR-7KD mice were analyzed by Flow cytometry.Results:Compared with those of WT (wild type) mice,the volume,weight index,and the total cells number of mesenteric lymph node were significantly increased ( P<0.05 ).Moreover ,the pathologic morphology was significantly changed.The proportion and numbers of T lymphocyte were significantly increased;however,the proportion of B lymphocyte were significantly decreased (P<0.05). Notably,the proportion and number of CD4+T cells and CD8+T cells were significantly increased (P<0.05).Meanwhile,CD62L+T cell proportion were vigorously reduced and CD 69+T cell and IFN-γ+T cell proportion were notably up-regulated,which belong to CD4+and CD8+T cell(P<0.05).Conclusion:There was significant influence in the proportion of αβT lymphocytes in mesenteric lymph nodes of miR-7KD mice,suggesting that miR-7 might play an important role in the composition and function of lymphocytes in mesenteric lymph nodes.