Background: Nucleolin (NCL) is the most abundant RNA-binding protein in the cell nucleolus and plays an important role in chromatin stability, ribosome assembly, ribosomal RNA maturation, ribosomal DNA transcription, nucleocytoplasmic transport, and regulation of RNA stability and translation efficiency. In addition to its anti-apoptotic properties, the underlying mechanisms associated with NCL-related roles in different cellular processes remain unclear. In this study, the effect of NCL on microRNA (miRNA) expression was evaluated by generating transgenic mice with myocardial overexpression of NCL and by analyzing microarrays of mature and precursor miRNAs from mice. Methods: Using microinjection of alpha-MyHc clone 26-NCL plasmids, we generated transgenic mice with myocardial overexpression of NCL firstly, and then mature and precursor miRNAs expression profiles were analyzed in NCL transgenic mice (n = 3) and wild-type (WT) mice (n = 3) by miRNA microarrays. Statistical Package for the Social Sciences version 16.0 software (SPSS, Inc., Chicago, IL, USA) was used to perform Student's t-test, and statistical significance was determined at P < 0.05. Results: Several miRNAs were found to be differentially expressed, of which 11 were upregulated and 4 were downregulated in transgenic mice with myocardial overexpression of NCL compared to those in WT mice. Several differentially expressed miRNAs were subsequently confirmed and quantified by real-time quantitative reverse transcription-polymerase chain reaction. Bioinformatics analysis was used for the prediction of miRNA targets. Furthermore, in vitro experiments showed that NCL regulated miR-21 expression following hydrogen peroxide preconditioning. Conclusions: Myocardial-protection mechanisms exerted by NCL might be mediated by the miRNAs identified in this study.

OBJECTIVE:To investigate the effect of nucleolin on cardiac cell apoptosis in Type 2 diabetic cardiomyopathy mice.
 Methods: Mice were fed with high-fat and high-sugar food for 20 weeks (mice were injected intraperitoneally with 60 mg/kg streptozotocin in the 5th and 6th weeks) to establish a mouse model of Type 2 diabetes. The mice were divided into 4 groups: a wild type (WT) control group, a nucleolin transgenic (TG) control group, a WT diabetic group, a TG diabetic group. Diabetes-related indicators were detected at the end of the 8th week. At the end of the 20th week, HE staining was used to observe myocardial morphological changes; TUNEL staining and caspase-3 activity were used to detect the extent of apoptosis of cardiac myocytes.
 Results: The level of fasting blood glucose was significantly increased in the diabetic group than that in the control group. In WT diabetic group, myocardial disarrangement, fragmentation and dissolution were observed (determined by HE staining); cellular apoptosis (determined by TUNEL staining and caspase-3 activity) also increased markedly in the WT diabetic group. Compared with the wild mice in the diabetic group, myocardial morphological changes and cardiac myocytes apoptosis were alleviated significantly. 
 Conclusion: Nucleolin overexpression affectes the occurrence and development of diabetic cardiomyopathy through inhibition of cardiac myocyte apoptosis.

OBJECTIVE:To investigate the nucleolus expression in the diabetic cardiomyopathy.METHODS:The rats were divided into a control group and a type II diabetic cardiomyopathy group (model group). In the model group, rats were fed with high-fat and high-sugar food (rats were intravenously injected with 60 mg/kg chain urea with cephalosporins in the 5th and 6th weeks in mice). The level of blood glucose was determined at the end of 8th week and the level of fasting blood glucose was examined at the end of 20th week. The ratio of the heart mass and body mass was calculated, and the pathological changes in myocardial morphology were observed. The immunohistochemical method and Western blot were used to detect the expression level of myocardial nucleolin.RESULTS:The level of fasting blood glucose was significantly increased in the diabetic model group than that in the control group (P<0.05). Rats in the model group were found hypertrophic cardic cells, with fracture, dissolusion, and disordered arrangement. Immunohistochemical staining and Western blot showed the protein levels of myocardial nucleolin in the model group were obviously higher than those in the control group (P<0.05).CONCLUSION:Nucleolin may play a role in the pathogenesis and development of the diabetic cardiomyopathy.

AIM:To construct myocardium-specific nucleolin ( Ncl) transgenic mice and to provide an animal model for the studies of the myocardial protection of nucleolin .METHODS:To create nucleolin transgenic mice , a myo-cardium-specific expression plasmid of nucleolin ( Alpha-MyHC clone 26-Ncl) was constructed .The gene type of transgenic mice was identified by PCR and the nucleolin protein level was tested by Western blotting .The myocardium morphology , heart weight index (HWI) and left ventricular pressure maximum rise rate were observed in nucleolin transgenic (TG) mice and wild-type ( WT) mice.RESULTS:We gained 4 transgenic mice (51, 52, 56 and 86 lines, only 52 line and 86 line were eugonic) by PCR.Western blotting analysis showed the expression of nucleolin up-regulated specifically in the myocardium .However , the myocardium morphology , HWI and left ventricular pressure maximum rise rate in the nucleolin transgenic mice were similar to those in the wild-type mice.CONCLUSION:We constructed myocardium-specific nucleo-lin transgenic mice successfully .

Aims Recent studies have identified the critical roles of nucleolin in a variety of cellular processes, including regulation of viral replication and tumour formation. However, the possible roles of nucleolin in myocardial preconditioning remain undefined.Methods and results We used an in vivo rat myocardial ischaemic preconditioning (IP) model (four cycles of 5 min ischaemia and 10 min reperfusion) and cellular hydrogen peroxide preconditioning (H2O2-PC) models. We found that nucleolin mRNA and protein expression showed a time-dependent increase during the recovery of myocardial ischaemic preconditioning in rats and H2O2-PC in neonatal rat cardiomyocytes. Nucleolin overexpression enhanced the protective effects of H2O2-PC, whereas nucleolin ablation abrogated the H2O2-PC-mediated protection in cardiomyocytes. On the other hand, nucleolin overexpression increased the stabilization of the HSPA1A mRNA and the expression of HSPA1A protein in cardiomyocytes, whereas nucleolin ablation abrogated the up-regulation of HSPA1A induced by H2O2-PC in cardiomyocytes. An interaction between nucleolin and HSPA1A mRNA was further identified using the RNA-protein interaction studies. Reporter gene assays, which depended on the untranslated regions (UTR) of HSPA1A mRNA, revealed that the post-transcriptional regulation was mainly attributed to the 3' UTR. Finally, HSPA1A anti-sense oligonucleotides (as ODNs) attenuated the protective effect of nucleolin in cardiomyocytes.Conclusion These results indicate that nucleolin is up-regulated and involved in myocardial protection of ischaemic preconditioning via a post-transcriptional control of HSPA1A expression.

Background: The present study aims to examine the expression patterns and roles of nucleolin during the recovery of heat-denatured human umbilical vein endothelial cells (HUVECs).Methods: Deep partial thickness burn model in Sprague-Dawley rats and the heat denatured cell model (52 degrees C, 35 s) were used. The expression of nucleolin was measured using Western blot analysis and real-time PCR. Angiogenesis was assessed using in vitro parameters including endothelial cell proliferation, transwell migration assay, and scratched wound healing. Gene transfection and RNA interference approaches were employed to investigate the roles of nucleolin.Results: Nucleolin mRNA and protein expression showed a time-dependent increase during the recovery of heat-denatured dermis and HUVECs. Heat-denaturation time-dependently promoted cell growth, adhesion, migration, scratched wound healing and formation of tube-like structures in HUVECs. These effects of heat denaturation on endothelial wound healing and formation of tube-like structures were prevented by knockdown of nucleolin, whereas over-expression of nucleolin increased cell growth, migration, and formation of tube-like structures in cultured HUVEC endothelial cells. In addition, we found that the expression of vascular endothelial growth factor (VEGF) increased during the recovery of heat-denatured dermis and HUVECs, and nucleolin up-regulated VEGF in HUVECs.Conclusions: The present study reveals that the expression of nucleolin is up-regulated, and plays a pro-angiogenic role during the recovery of heat-denatured dermis and its mechanism is probably dependent on production of VEGF.General significance: We find a novel and important pro-angiogenic role of nucleolin during the recovery of heat-denatured dermis. (c) 2013 Elsevier B.V. All rights reserved.

OBJECTIVE:To observe the effect of recombinant human interleukin-11 on the platelet counts and the CFU-Meg of the marrow cell culture.METHODS:Thrombocytopenia models of guinea pigs were made by injecting subcutaneously anti-platelet serum.RESULTS:200, 100, and 50 micrograms.kg-1 of rHuIL-11 increased the CFU-Meg of the marrow cell culture and the peripheral platelet, showing a significant difference from that of the control group (P < 0.05).CONCLUSION:rHuIL-11 has a significantly therapeutic effect on thrombocytopenia models induced by anti-platelet serum in guinea pigs.

OBJECTIVE:To observe the effect of the recombinant human granulocyto colony-stimulating factor (rhG-CSF) on radiation-induced neutropenia models of mice. METHODS:rhG-CSF in 2 different doses (10 micrograms.kg-1.d-1 and 30 micrograms.kg-1.d-1) was injected respectively to radiation-induced neutropenia models of mice. The effect of rhG-CSF on the weight of the spleen, CFU-S, leukocyte counts, neutrophil counts, and CFU-GM of the marrow cell culture was observed. RESULTS:Both 30 and 10 micrograms.kg-1.d-1 of rhG-CSF increased CFU-GM of the marrow cell culture and the peripheral leukocyte and neutrophil, showing a significant difference compared with the NS control group (P < 0.05). CONCLUSION:rhG-CSF has a significant therapeutic effect on radiation-induced agranulocytosis models of mice.