Objective:To investigate the effect and mechanism of miRNA-24 on the proliferation,migration and tube formation of vascular endothelial cells.Methods:Human umbilical vein endothelial cells(HUVECs)were assigned into co...Objective:To investigate the effect and mechanism of miRNA-24 on the proliferation,migration and tube formation of vascular endothelial cells.Methods:Human umbilical vein endothelial cells(HUVECs)were assigned into control,microRNA(miR)-24 overexpression and anti-miR-24 groups.The proliferation and migration abilities of HUVECs were detected by methyl thiazolyl tetrazolium(MTT)assay and scratch wound healing assay,respectively.The ability of HUVECs to form tubular structures was evaluated by a tube formation assay.The mRNA and protein expressions of vascular endothelial growth factor(VEGF)and transcription factor Sp1 were determined by RT-PCR,immunocytochemistry and western blotting,respectively.Results:The miR-24 overexpression group exhibited decreased cell proliferation and migration,and expressions of VEGF and Sp1 compared with the control group(P <0.01).No tube-like network structure was formed in the miR-24 overexpression group.However,inhibition of miR-24 in HUVECs markedly increased cell proliferation and migration,enhanced tube formation and expressions of VEGF and Sp1(P<0.05 or P<0.01).Conclusion:MiR-24 suppressed the proliferation,migration and tube formation of HUVECs,and the mechanism might be related to the down-regulation of VEGF expression.Sp1 might participate in this regulation process.展开更多
Objective:To investigate the effects of miR-24 on the expression of vascular endothelial nitric oxide synthase(eNOS)and plasma nitric oxide(NO)level in rats.Methods:The miR-24 over-expression plasmid was constructed.T...Objective:To investigate the effects of miR-24 on the expression of vascular endothelial nitric oxide synthase(eNOS)and plasma nitric oxide(NO)level in rats.Methods:The miR-24 over-expression plasmid was constructed.Twenty healthy male Sprague-Dawley rats were randomly divided into two groups:miR-24 group and blank plasmid group.Rats were injected with plasmid DNA in saline via the tail vein.After eight weeks,the rat artery was removed and HE staining was used to observe the morphological changes.The protein expression and activity of eNOS were detected by immunohistochemistry and enzyme-linked immunosorbent assay(ELISA),respectively,and the NO level in plasma was determined by nitrate reduction assay.Results:Compared with the blank plasmid group,the expression and activity of eNOS as well as the NO production in the miR-24 group was significantly decreased(P <0.05 or P <0.01).No significant difference in the morphology of vascular tissue was noted between the two groups.Conclusion:Up-regulation of miR-24 inhibits the expression of eNOS and NO production in rat vascular tissue.It may provide a bio-target for the development of drugs to treat cardiovascular diseases such as hypertension.展开更多
This study was conducted to investigate the effect of weaning age on growth performance, nutrient digestion and metabolism, and serological indicators, and to obtain an optimal weaning age in Hu lambs.Forty-eight newb...This study was conducted to investigate the effect of weaning age on growth performance, nutrient digestion and metabolism, and serological indicators, and to obtain an optimal weaning age in Hu lambs.Forty-eight newborn Hu lambs(birth weight, 2.53 ± 0.14 kg) were randomly divided into 4 groups. The lambs in control group(ER) suckled their dams. The lambs in other three experimental groups were weaned on milk replacer at 10.20, and 30 days of age(EW10, EW20, and EW30 groups),respectively. The results were as follows: 1) lambs in EW10 and EW30 groups had a lower(P < 0.05) ADG than those in ER group within 10 days post-weaning; the weaned lambs began to show a higher(P < 0.05) ADG than those in ER group after 20 days post-weaning. 2) EW10 and EW20 groups had a higher(P < 0.05) creep feed intake than EW30 and ER groups from 15 to 60 days of age. 3) The apparent digestibility of dry matter, organic matter, gross energy, nitrogen, ether extract and phosphorus, and the deposition of nitrogen and phosphorus did not differ(P > 0.05) among groups; however, the apparent digestibility and deposition of calcium in early weaned lambs were lower(P < 0.05) than those in ewe-reared lambs. 4)The albumin content in EW30 group was lower(P < 0.05) than that in ER group; the globulin content in EW30 group was higher(P < 0.05) than that in other groups; the content of serum insulin-like growth factor-1 in weaned lambs tended to increase compared with lambs in ER group. Finally, the growth rate of lambs decreased within 10 days post-weaning, but early weaning boosted creep feed intake, leading to better growth and health later in life. The Hu lambs can be weaned on milk replacer and creep feed at 10 days of age.展开更多
基金supported by the National Natural Science Foundation of China(No.81373403)
文摘Objective:To investigate the effect and mechanism of miRNA-24 on the proliferation,migration and tube formation of vascular endothelial cells.Methods:Human umbilical vein endothelial cells(HUVECs)were assigned into control,microRNA(miR)-24 overexpression and anti-miR-24 groups.The proliferation and migration abilities of HUVECs were detected by methyl thiazolyl tetrazolium(MTT)assay and scratch wound healing assay,respectively.The ability of HUVECs to form tubular structures was evaluated by a tube formation assay.The mRNA and protein expressions of vascular endothelial growth factor(VEGF)and transcription factor Sp1 were determined by RT-PCR,immunocytochemistry and western blotting,respectively.Results:The miR-24 overexpression group exhibited decreased cell proliferation and migration,and expressions of VEGF and Sp1 compared with the control group(P <0.01).No tube-like network structure was formed in the miR-24 overexpression group.However,inhibition of miR-24 in HUVECs markedly increased cell proliferation and migration,enhanced tube formation and expressions of VEGF and Sp1(P<0.05 or P<0.01).Conclusion:MiR-24 suppressed the proliferation,migration and tube formation of HUVECs,and the mechanism might be related to the down-regulation of VEGF expression.Sp1 might participate in this regulation process.
基金supported by the National Natural Science Foundation of China(No. 03101213068D)Guangxi Master Postgraduate Research Innovation Project(No.YCSZ2015119)
文摘Objective:To investigate the effects of miR-24 on the expression of vascular endothelial nitric oxide synthase(eNOS)and plasma nitric oxide(NO)level in rats.Methods:The miR-24 over-expression plasmid was constructed.Twenty healthy male Sprague-Dawley rats were randomly divided into two groups:miR-24 group and blank plasmid group.Rats were injected with plasmid DNA in saline via the tail vein.After eight weeks,the rat artery was removed and HE staining was used to observe the morphological changes.The protein expression and activity of eNOS were detected by immunohistochemistry and enzyme-linked immunosorbent assay(ELISA),respectively,and the NO level in plasma was determined by nitrate reduction assay.Results:Compared with the blank plasmid group,the expression and activity of eNOS as well as the NO production in the miR-24 group was significantly decreased(P <0.05 or P <0.01).No significant difference in the morphology of vascular tissue was noted between the two groups.Conclusion:Up-regulation of miR-24 inhibits the expression of eNOS and NO production in rat vascular tissue.It may provide a bio-target for the development of drugs to treat cardiovascular diseases such as hypertension.
基金supported by the Special Fund for Agro-scientific Research in the Public Interest(201303143)China Scholarship Council Fund(201403250010)
文摘This study was conducted to investigate the effect of weaning age on growth performance, nutrient digestion and metabolism, and serological indicators, and to obtain an optimal weaning age in Hu lambs.Forty-eight newborn Hu lambs(birth weight, 2.53 ± 0.14 kg) were randomly divided into 4 groups. The lambs in control group(ER) suckled their dams. The lambs in other three experimental groups were weaned on milk replacer at 10.20, and 30 days of age(EW10, EW20, and EW30 groups),respectively. The results were as follows: 1) lambs in EW10 and EW30 groups had a lower(P < 0.05) ADG than those in ER group within 10 days post-weaning; the weaned lambs began to show a higher(P < 0.05) ADG than those in ER group after 20 days post-weaning. 2) EW10 and EW20 groups had a higher(P < 0.05) creep feed intake than EW30 and ER groups from 15 to 60 days of age. 3) The apparent digestibility of dry matter, organic matter, gross energy, nitrogen, ether extract and phosphorus, and the deposition of nitrogen and phosphorus did not differ(P > 0.05) among groups; however, the apparent digestibility and deposition of calcium in early weaned lambs were lower(P < 0.05) than those in ewe-reared lambs. 4)The albumin content in EW30 group was lower(P < 0.05) than that in ER group; the globulin content in EW30 group was higher(P < 0.05) than that in other groups; the content of serum insulin-like growth factor-1 in weaned lambs tended to increase compared with lambs in ER group. Finally, the growth rate of lambs decreased within 10 days post-weaning, but early weaning boosted creep feed intake, leading to better growth and health later in life. The Hu lambs can be weaned on milk replacer and creep feed at 10 days of age.
