Objective To construct lentiviral vector carrying rat′s calcitonin gene-related peptide(CGRP) gene for the following-up study on the function of CGRP .Methods CGRP gene segment was subcloned into shuttle plasmid ,become Puc57-CGRP .The pLenO-DCE-CGRP expression vector was be constructed by double digests .The pLenO-DCE-CGRP and 4 auxiliary packaging plas-mids were co-transfected into 293T cells .Cells were cultured for 48 hours .The supernant was collected and concentrated ,and then the viral titers were tested by multiple proportions dilution method and flow cytometer .The expression levels of CGRP were detec-ted in CGRP-modified 293T cells by Real-time PCR .Results The results of digestion and sequencing show that the pLenO-DCE-CGRP vector was constructed successfully .The titer of the lentiviral particles was 5 .1 × 108 TU /mL .Conclusion The high-titer lentvirus vector containing CGRP gene is constructed successfully ,which lay a foundation for transfecting mesenchymal stem cell (MSC) and studying the function of CGRP .

Objective To investigate the effect of transplantation of CXC receptor 4 (CXCR4)gene-modified bone marrow mesenchymal stem cells (BMSCs) on repairment of carotid injure in rats.Methods BMSCs were cultured and transfected with lentivirus vector carrying CXCR4 gene to generate CXCR4 gene-modified BMSCs (CXCR4-BMSCs).CXCR4 expression was detected by Western blot.Rat model of carotid artery balloon injury was established.Rats were randomly divided into the PBS control group (n=12),CXCR4-BMSCs group (n=12) and BMSCs group (n=12).Two weeks after transplantation,the injured arteries were obtained.The homing of BMSCs was detected by immunofluorescence with green fluorescent protein (GFP).Platelet endothelial cell adhesion molecule (CD31) expression was detected by immunofluorescence staining.At 4 weeks after transplantation,proliferating cell nuclear antigen (PCNA) expression was determined by immunohistochemical staining,and the vascular morphological changes were observed by hematoxylineosin staining (HE).Results Compared with the control and BMSCs groups,the protein level of CXCR4 was increased in CXCR4-BMSCs group (both P＜0.05).The percentage of GFP-positive cells homing were much more in CXCR4-BMSCs group than in BMSCs group [(58.8±4.4)％ vs.(36.2±5.0) ％,P＜0.05].The CD31 expression were higher in CXCR4-BMSCs group than in BMSCs group [(58.8±4.3)％ vs.(28.8±4.2)％,P＜0.05].Compared to the control group,the PCNA expression was decreased in CXCR4-BMSCs and BMSCs groups [(21.0±4.2) ％,(36.5±4.9) ％vs.(78.3±3.5) ％,both P＜0.05].There was a significant difference in PCNA expression between the CXCR4-BMSCsgroupandBMSCs group [(21.0±4.2)％vs.(36.5±4.9)％,P＜0.05].The neointimal area and the ratio of neointimal/medial area were decreased in CXCR4 BMSCs and BMSCs group as compared with the control group [(0.205±0.018) mm2,(0.323±0.071) mm2 vs.(0.536 ± ±0.054) mm2; (1.039±0.123),(1.660±0.404) vs.(2.460±0.328); all P＜0.05],and there were significant differences in neointimal area and the ratio of neointimal/medial area in CXCR4-BMSCs group and BMSCs group [[(0.205±0.018) mm2 vs.(0.323±0.071) mm2,(1.039±0.123)vs.(1.660±0.404),both P＜0.05].Conclusions CXCR4 gene-modified BMSCs may increase the CXCR4 expression in BMSCs.CXCR4-BMSCs transplantation is more effective than BMSCs transplantation in increasing BMSCs homing capacity,reducing the reendothelialization and vascular restenosis.

Objective To observe the effect of adenovirus- receptor activity modifying protein-1 (RAMP1) on nuclear factor(NF κB) and myocardial fibrosis in heart of rabbit with myocardial infarction. Methods Myocardial infarction (MI) models were developed in 54 rabbits and they were randomly divided into RAMP1 group,EGFP group and control group according to whether pAd2-EGFP-RAMP1,pAd2-EGFP or PBS was injected into infarction region and its border.At 7 d,14 d and 28 d after injection,Left ventricular function indices such as LVEF,LVSd,LVDd and LVFS were estimated by echocardiogram,the expression of NF-κB in myocardium was detected by Western blot,the plasma level of TNF-α was measured by ELISA,and fibrosis and collagen content was measured by Masson stain. Results At 7 d after adenovirus injection,the expression of RAMP1was significantly increased in RAMP1 group (67.33 ± 3.97)％ as compared to EGFP group(20.59 ±3.26) ％ and PBS group ( 23.80 ± 5.08) ％ ( P ＜ 0.05 ).The expression of NF κB was decreased in RAMP1 group ( 26.54 ± 5.13 ) ％ versus EGFP group (62.60 ± 6.18) ％ and PBS group (62.95 ±5.17)％ (P＜0.05).The plasma level of TNF-α was lower in RAMP1 group than in EGFP group and in PBS group at different time[7 d:( 136.74 ± 5.42) μg/L vs.( 196.97 ± 14.17) μg/L,(203.67 ±13.90)μg/L; 14 d:( 154.51 ± 13.61 )]μg/L vs.( 112.22±6.74 )μg/L,(160.46± 14.27)μg/L ;28 d;(51.10± 5.62)μg/L vs.( 95.55 ± 9.94 )μg/L,( 98.96 ± 12.68) μg/L,all P＜ 0.05].The collagen content was reduced in RAMP1 group as compared with EGFP group and PBS group at 14 d and 28 d [14 d:(7.10±0.98)％ vs.(19.52±2.32)％,(17.91±0.96)％ ;28 d:(17.04±2.44)vs,(34.10±5.59) ％,(33.98±4.33)％,all P＜0.01].At 28 d after infarction,the infarct size was decreased in RAMP1 group (26.54 ± 5.13) ％ compared with EGFP group (32.20 ± 3.73) ％ and control group (35.58±2.65) ％ (P＜0.01),and better heart function appeared in RAMP1 group. Conclusions The high-expression of RAMP1 could decrease the collagen deposition and fibrosis in the border of infarction and improve heart function through lower expression of NF-κB and decreasing the plasma level of TNF-α.

Objective To explore in vitro mesenchymal stem cell (MSC) transfection of lentiviral vector mediated calcitonin gene‐related peptide(CGRP) gene and its effects on biological properties of MSC .Methods MSC were isolated ,cultured and identi‐fied .MSC were infected by lentivirus encoding recombinant enhanced green fluorescent protein (EGFP) gene and CGRP (Lv‐EG‐FP‐CGRP) .The transfection efficiency was determined by the inverted fluorescence microscope and flow cytometry .The expression levels of CGRP were detected in CGRP‐modified MSC by using real‐time PCR ,immunocytochemistry and enzyme‐linked immu‐nosorbent assay (ELISA) .The proliferation ,aging and differentiation ability of MSC were evaluated by MTT ,β‐galactosidase stai‐ning and inducing differentiation respectively .Results After 48 h of MSC transfection by Lv‐EGFP‐CGRP ,EGFP/CGRP could be expressed stably .When multiplicity of infection (MOI) was 30 ,the transfection efficiency reached more than 80% .Compared with the MSC group and the MSC‐EGFP group ,the mRNA and protein expression levels of CGRP in CGRP‐modified MSC(MSC‐CGRP group) were markedly increased(all P<0 .01) .The results of MTT ,β‐galactosidase staining and inducing differentiation assay dem‐onstrated that the transfected CGRP basically had no effect on the proliferation ,aging and endotheliocyte differerntiation of MSC . Conclusion MSC is a kind of ideal genetic vector cell ,which can serve as the target cell of CGRP gene transduction for the applica‐tion of gene therapy and lays the foundation for follow‐up in vitro and vivo experiments .

Objective To study the effect of the recombinant Lentivirus containing calcitonin gene related peptide (CGRP) gene on cells biological activity and differentiation of rat bone marrow stem cells(MSCs).Methods Rat MSCs were isolated and cultured by granulocytes adherent.MSCs were transfected with Lenti-EGFP CGRP(MSCsCGRP+/+ group),While MSCs were transfected with Lenti-EGFP as control group.Cell transfection rate was detected by flow cytometry,protein secretion in the above-mentioned MSCsCGRP+ + supernatant was detected using ELISA method.Cells surface markers weare detected by flow cytometry and immunohistochemistry.Trypan blue was used to examin the survive rate,β galactosidase staining was used to examin aging of MSCs transfection,and MTT was used to examine cell vitality.Results At first day after transfecting with Lenti-EGFP-CGRP,fluorescence was not observed by fluorescence microscope,but a small amount of CGRP protein was detected by ELISA in MSCsCGRP+/+ group,at 3 days and 4 days after transfecting with MSCs,strong fluorescence was observed by fluorescence microscope (the cell transfection rates were 77.87％ and 79.58％).The CGRP expression was significantly higher in MSCsCGRP+ + group than in control group [(19.53±0.50) pg/ml vs.(3.12±0.00) pg/ml,t=48.964,P＜0.01].At three days after transfection with MSCs,CD29 and CD90 expression were significantly higher,as compared with control group,CD31 expression was increased in MSCsCGRP+ /+ group.Seven days after transfection with MSCs,CD31 expression was significantly increased in MSCsCGRP+ + group,vWF expression was significantly increased in MSCsCGRP+ + group after MSCs were transfected with LentiEGFP CGRP for 14 days,but a SMA expression was decreased in MSCsCGRP+ +group.At 3 days and 7 days after transfection with Lenti-EGFP-CGRP,the proliferation,survive and aging showed no difference in MSCsCGRP+/+group and in control group (the proliferation of cell:t=0.253,0.290the survive of cell t=-0.307,0.690,all P＞0.05).At 14 days after transfection with Lenti-EGFP-CGRP,aging of cell were decreased in MSCsCGRP+ + group as compared with control group (t=2.446,P＜ 0.05).Conclusions After MSCs are transfected with Lenti EGFP-CGRP,biological characteristics of MSCs has no significant effects,there is still proliferation and differentiation activity.Cell secretion of CGRP can promote the endothelial cell differentiation,and inhibit the differentiation to smooth muscle cells.The CGRP modification of MSCs may play a role in the regulation of angiogenesis.

Objective: To investigate whether microRNA(miR)-214 can improve hyperglycemia induced pyroptosis in H9c2 cells through targeting caspase-1. Methods: H9c2 cells of rats those in good growth condition were selected and incubated into the T25 culture bottle after digestion and passage. Cells were cultured in an incubator at 37 ℃ with 5%CO₂, repeat passage was made after cell density reached about 80%, The 5^th to 8^th generations of cells were selected for the subsequent experiments. To observe the effect of overexpression of miR-214 on pyroptosis and caspase-1 expression in H9c2 cells induced by hyperglycemia, the cells were divided into 4 groups: Control group(H9c2 cells cultured normally), Hyperglycemia group (HG group, 50 mmol/L glucose was used to intervene H9c2 cells for 24 hours), miR-214 mimics+hyperglycosis group (mimics+HG group, H9c2 cells were transfected with miR-214 mimics for 24 hours and then treated with 50 mmol/L hyperglycosis for 24 hours), miR-214 mimic-negative control+hyperglycaemic group(MNC+HG group, H9c2 cells were transfected with miR-214 mimic-negative control for 24 hours and then treated with 50 mmol/L hyperglycaemic for 24 hours). In order to further verify the anti-pyroptosis effect of miR-214 was mediated by targeted inhibition on caspase-1, cells overexpressing caspase-1 were used in the rescue experiment. The cells overexpressing caspase-1 were divided into 4 groups: Hyperglycemia group (HG group, 50 mmol/L glucose was used to intervene H9c2 cells for 24 hours), miR-214 mimics+hyperglycosis group (mimics+HG group, H9c2 cells were transfected with miR-214 mimics for 24 hours and then treated with 50 mmol/L hyperglycosis for 24 hours), miR-214 mimics+hyperglycosis+recombinant adenovirus (Ad-caspase-1-EGFP) group with caspase-1 gene and EGFP green fluorescent protein expression (mimics+HG+Ad-caspase-1-EGFP group, H9c2 cells were transfected with caspase-1-green fluorescent protein-carrying adenovirus for 48 hours, followed by transfection of miR-214 mimics for 24 hours, and then treated with 50 mmol/L hyperglycaemia for 24 hours), miR-214 mimics+HG+Ad-EGFP empty virus group (mimics+HG+Ad-EGFP group, H9c2 cells were transfected with empty adenovirus containing green fluorescent protein for 48 hours, followed by transfection with miR-214 mimics for 24 hours, and then treated with 50 mmol/L hyperglycosis for 24 hours). The mRNA expression levels of miRNA-214 and caspase-1 in cells were detected by real-time quantitative PCR. The expression and localization of caspase-1 protein were detected by immunofluorescence assay. Western blot was used to detect protein expression levels of procaspase-1, cleaved caspase-1, NLRP3 and ACS with β-actin as internal reference. The secretion of IL-1β and IL-18 in cell culture medium was detected by ELISA. The correlation between miR-214 and caspase-1 was detected by double luciferase reporter gene. Results: (1) The mRNA expression levels of miR-214 and caspase-1 in each group: the mRNA expressions of miR-214 in HG group and MNC+HG group were significantly lower than that in control group(P<0.05). The mRNA expression of miR-214 in mimics+HG group was significantly higher than that in control group (P<0.05). The mRNA expression levels of caspase-1 in HG group and MNC+HG group were significantly higher than that in control group(P<0.05). The mRNA expression level of caspase-1 in mimics+HG group was lower than that in control group(P<0.05). (2) The expression of caspase-1 in each group: the green fluorescence intensity in the control group was weak, which was strong in the HG group and MNC+HG group. The green fluorescence expression was weaker in mimics+HG group than in HG group. (3) ASC and NLRP3 protein expression levels in each group: ASC and NLRP3 protein expression levels in HG group and MNC+HG group were higher than those in control group(P<0.05). ASC and NLRP3 protein expression levels were significantly lower in mimics+HG group than in mimics+HG group (P<0.05). (4) The secretion of IL-1β and IL-18 in the cell culture medium of each group: the content of IL-1β and IL-18 in the cell culture medium of HG group and MNC+HG group was significantly higher than that of control group (P<0.05). The content of IL-1β and IL-18 in the cell culture medium of mimics+HG group was significantly lower than that of the HG group (P<0.05). (5) Correlation between miR-214 and caspase-1: miR-214 specifically binds to caspase-1 3 ′UTR. Meanwhile, Western blot results showed that cleaved caspase-1 protein expression levels were significantly higher in both HG group and MNC+HG group than in control group (P<0.05). The levels of cleaved caspase-1 were significantly lower in mimics+HG group than in HG group (P<0.05). There was no significant difference in procaspase-1 expression among groups (P>0.05). (6) The expression levels of procaspase-1, cleaved caspase-1, ASC and NLRP3 in each group in rescue experiment: there was no significant difference in the expression of procaspase-1 in each group (P>0.05). Cleaved caspase-1, ASC and NLRP3 protein expressions were significantly lower in mimics+HG group than in HG group (P<0.05). However, cleaved caspase-1, ASC and NLRP3 protein expressions were significantly higher in mimics+HG+ Ad-caspase-1-EGFP group than in mimics+HG group (P<0.05). (7) The expression of IL-1β and IL-18 in rescue experiment: the secretions of IL-1β and IL-18 in the cell culture medium of the mimics+HG group were significantly lower than that of HG group (P<0.05), which were significantly higher in mimics+HG+Ad-caspase-1-EGFP group than in mimics+HG group (P<0.05). Conclusion miR-214 can improve the hyperglycemia induced pyroptosis in H9c2 cells by targeted inhibition of the caspase-1.

OBJECTIVETo investigate the impact of calcitonin gene-related peptide (CGRP) modified bone marrow mesenchymal stem cell (MSC) on the migration of vascular smooth muscle cell (VSMC) and related mechanisms.

METHODSThe MSC and VSMC were isolated from rats and cultured, CGRP was transfected to MSC with the high expression lentivirus vector, VSMC was transfected with high expression lentivirus vector of receptor activity modifying protein 1 (RAMP1) and the silence expression lentivirus vector of RAMP1. Then MSC was co-cultured with VSMC. Experimental groups were as follows: (1) Ang II group (MSC + VSMC + Ang II); (2) MSC(CGRP+) group (MSC(CGRP+) + VSMC + Ang II); (3) MSC(CGRP+) RAMP1(-) group (MSC(CGRP+) + VSMC(RAMP1-) + Ang II); (4) MSC(CGRP+) RAMP1(+) group (MSC(CGRP+) + VSMC(RAMP1+) + Ang II); (5) RAMP1(+) group (MSC + VSMC(RAMP1+) + Ang II). Transwell assay was applied to detect the migration of smooth muscle cells, Western blot was applied to detect the protein expression of cells in various groups.

RESULTSVSMC migration number was significantly lower in MSC(CGRP+) group compared with Ang II group (50.8 ± 2.6 vs. 71.4 ± 2.3, P < 0.05), but higher than in MSC(CGRP+) RAMP1(+) group (50.8 ± 2.6 vs. 30.4 ± 3.0, P < 0.05). When RAMP1 expression reduced in VSMC, compared with MSC(CGRP+) RAMP1(+) group, VSMC migration increased in the MSC(CGRP+) RAMP1(-) group compared to MSC(CGRP+)RAMP1(+) (69.0 ± 5.6 vs. 30.4 ± 3.0, P < 0.05) and was similar to Ang II group (69.0 ± 5.6 vs. 71.4 ± 2.3, P > 0.05) and RAMP1(+) group (71.6 ± 3.4). According to the result of Western blot, P-P65 protein expression in MSC(CGRP+) group was lower than that in Ang II group (0.475 ± 0.022 vs.0.642 ± 0.035, P < 0.05). P-P65 protein expression in MSC(CGRP+)RAMP1(-) group was higher than that in MSC(CGRP+) RAMP1(+) group (0.670 ± 0.030 vs. 0.373 ± 0.041, P < 0.05), and there was no difference between MSC(CGRP+)RAMP1(-) group and Ang II group (P > 0.05). P-P65 protein expression was similar between RAMP1(+) group (0.643 ± 0.039) and Ang II group (P > 0.05).

CONCLUSIONSCGRP inhibits VSMC migration through RAMP1. NF-κB and RAMP1 play crucial role in the inhibiting effects of CGRP on VSMC migration. Thus, RAMP1-CGRP signaling inhibits VSMC migration through NF-κB signal pathways.

Animals ; Bone Marrow Cells ; Calcitonin Gene-Related Peptide ; Cell Movement ; Coculture Techniques ; Hematopoietic Stem Cells ; In Vitro Techniques ; Muscle, Smooth, Vascular ; Myocytes, Smooth Muscle ; NF-kappa B ; Rats ; Receptor Activity-Modifying Protein 1 ; Signal Transduction ; Transfection