Mechanism of CD137 signal regulating P53/P21 pathway to promote senescence of vascular smooth muscle cells / 中华老年心脑血管病杂志

Objective To explore the mechanism by which CD137 signal regulates the aging of vas-cular smooth muscle cells(VSMCs).Methods Thirty 8-week-old male C57BL/6J mice were ran-domly divided into a young group(8 weeks old)and an aged group(80 weeks old),with 30 mice in each group.After corresponding periods of feeding,the mice were euthanized,and the plasma and aortic blood vessels were isolated.In the cell experiments,normal VSMCs were divided into a control group,bleomycin(BLM)group,combined agonist group,and combined inhibitor group.The cellular senescence level of VSMCs was assessed using a cellular senescence β-galactosidase staining kit.Western blotting and PCR were employed to examine the expression of senescence-related proteins in tissues and cells,while ELISA was utilized to measure the expression of senes-cence-related inflammatory factors.Results The expression of CD137 and γ-H2AX in the aorta was significantly higher,while that of PCNA was obviously lower in the aged group than the young group(P＜0.05).The plasma level of CD137 was notably higher in the aged group than the young group(154.0±4.1 pg/ml vs 98.0±2.3 pg/ml,P＜0.05).Compared with the normal control group,there were significantly more aged VSMCs in the BLM group(P＜0.05).While,treatment of combined agonist resulted in larger amount of aged VSMCs when compared with the BLM group(P＜0.05),which was reversed by combined inhibitor treatment(P＜0.05).The levels of TNF-α,IL-6 and IL-1β were significantly elevated in the BLM group than the normal control group(P＜0.05).The combined agonist group had even higher levels of TNF-α,IL-6,and IL-1βthan the BLM group(P＜0.05),but the levels were decreased in the combined inhibitor group(P＜0.05).Compared with the normal control group,the expression of Bcl-2,γ-H2AX,P53,and P21 were significantly increased in the BLM group,combined agonist group,and combined inhibi-tor group,while that of PCNA was significantly decreased(P＜0.05).Compared with the BLM group,the expression of P53 and P21 in the combined agonist group showed an increase(P＜0.05),and the expression of P53 was significantly decreased in the combined inhibitor group(P＜0.05).Conclusion CD137 signal regulates the P53/P21 pathway to promote VSMC aging.

Effect of salvianolic acid B on inflammatory responses of vascular smooth muscle cells in septic mice: role of circACTA2 / 中华麻醉学杂志

Objective:To evaluate the effect of Salvianolic acid B (Sal B) on the inflammatory responses of vascular smooth muscle cells (VSMCs) in septic mice and the role of circACTA2.Methods:In vivo experiment Eighty-one healthy male C57BL/6 mice, aged 6-8 weeks, were divided into 3 groups ( n=27 each) by a random number table method: sham operation group, sepsis group and Sal B group. Sepsis model was developed by cecal ligation and puncture. After sucessful preparation of the model, Sal B 7 mg/kg/d was intraperitoneally injected once a day for 2 consecutive days in Sal B group. Twenty mice in each group were randomly selected to measure systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and whole blood lactic acid (Lac) and to record the survival within 7 days after developing the model. Seven mice in each group were randomly selected at 48 h after developing the model, and the arterial vascular tissues were collected for determination of the expression of interleukin-1beta (IL-1β) (by immunofluorescence staining), expression of IL-1β, tumor necrosis factor-alpha (TNF-α) and IL-6 protein and mRNA (by Western blot and quantitative real-time polymerase chain reaction, respectively), and expression of circACTA2 (by quantitative real-time polymerase chain reaction). Cell experiment Mouse VSMCs were cultured and divided into 6 groups ( n=3 each) by a random number table method: control group (C group), lipopolysaccharide (LPS) group, Sal B group, si-circACTA2+ C group, si-circACTA2+ LPS group, and si-circACTA2+ Sal B group. The cells were incubated for 24 h with LPS (final concentration 1 μg/ml) in LPS group and with LPS (final concentration 1 μg/ml) and Sal B (final concentration 5 μmol/L) in Sal B group. VSMCs were transfected with si-circACTA2 only in si-circACTA2+ C group. At 24 h after transfection of si-circACTA2 into VSMCs, the cells were incubated with LPS (final concentration 1 μg/ml) in si-circACTA2+ LPS group and with LPS (final concentration 1 μg/ml) and Sal B (final concentration 5 μmol/L) for 24 h in si-circACTA2+ Sal B group. The expression of IL-1β, TNF-α and IL-6 protein and mRNA was detected using Western blot and quantitative real-time polymerase chain reaction, and the expression of circACTA2 was determined by the quantitative real-time polymerase chain reaction. Results:In vivo experiment Compared with sham operation group, SBP, DBP and MAP were significantly decreased, the concentrations of whole blood Lac were increased, 7-day survival rate was decreased, the expression of IL-1β, TNF-α and IL-6 protein and mRNA in arterial vascular tissues was up-regulated, circACTA2 expression was down-regulated ( P<0.05), and the fluorescence of IL-1β was enhanced in sepsis group. Compared with sepsis group, SBP, DBP and MAP were significantly increased, whole blood Lac concentrations were decreased, 7-day survival rate was increased, the expression of IL-1β, TNF-α and IL-6 protein and mRNA in arterial vascular tissues was down-regulated, the expression of circACTA2 was up-regulated ( P<0.05), and the fluorescence of IL-1β was weakened in Sal B group. Cell experiment Compared with group C, the expression of IL-1β, TNF-α and IL-6 protein and mRNA was significantly up-regulated, and the expression of circACTA2 was down-regulated in LPS group ( P<0.05). Compared with LPS group, the expression of IL-1β, TNF-α and IL-6 protein and mRNA was significantly down-regulated, and the expression of circACTA2 was up-regulated in Sal B group ( P<0.05). Compared with si-circACTA2+ C group, the expression of IL-1β, TNF-α and IL-6 protein and mRNA was significantly up-regulated in si-circACTA2+ LPS group ( P<0.05). There were no significant differences in the expression of IL-1β, TNF-α and IL-6 protein and mRNA between si-circACTA2+ LPS group and si-circACTA2+ Sal B group ( P>0.05). Conclusions:Sal B can reduce the inflammatory responses of VSMCs, and the mechanism may be related to promoting the expression of circACTA2 in septic mice.

Research progress of ferroptosis in aortic dissection / 中华老年医学杂志

Aortic dissection, especially Stanford type A aortic dissection, is an acutely progressive and highly fatal cardiovascular disease.Early prevention and timely treatment can greatly reduce mortality and reduce the burden on families and society.However, due to the etiological mechanism is still unclear, the clinical treatment is still mainly surgery, and the early prevention and drug application are very limited.And some recent studies have found that ferroptosis may play an important role in the occurrence and development of aortic dissection, revealing the relationship between them may provide ideas for the prevention, treatment and scientific research of the disease.

Study on the mechanism of the expression of microRNA-206 in chronic obstructive pulmonary disease and its effect on the proliferation of human airway smooth muscle cells / 中国医师进修杂志

Objective:To investigate the expression of microRNA (miR)-206 in chronic obstructive pulmonary disease (COPD) and its effect on the proliferation of human airway smooth muscle cells (HASMCs) and to explore its mechanism.Methods:Lung tissue samples of 15 patients with COPD (COPD group) who underwent lung volume reduction surgery in the General Hospital of Ningxia Medical University from September 2017 to September 2018 and of 15 patients with benign lung tumors without a history of COPD were collected. Microarray technology was used to analyze the miR and RNA omics in lung tissues of 4 COPD patients and normal controls, and reverse transcriptase polymerase chain reaction(RT-PCR) was used to verify the results. Bioinformatics and double luciferase gene reporting assay were used to detect the target genes of miR-206 in HASMCs. The miR-206 mimic/inhibitor was transfected into HASMCs by liposome transfection technology, and the expression level of miR-206 was detected by RT-PCR. Methyl thiazolyl tetrazolium (MTT), flow cytometry and apoptosis assay were used to detect the effects of miR-206 on the proliferation, cell cycle and apoptosis of HASMCs. The expression of PTEN, cell cycle and apoptotic protein in HASMCs was detected by Western blot.Results:The results of miR and mRNA omics analysis showed that the expressions of miR-206, miR-3187-5p and miR-124 in COPD group were significantly up-regulated (0.09 ± 0.01 vs. 2.17 ± 0.57, 0.60 ± 0.04 vs. 1.32 ± 0.15, 0.22 ± 0.08 vs. 1.09 ± 0.23) ( P<0.05), while the expressions of miR-574 and miR-337-3p decreased significantly (0.79 ± 0.03 vs. 0.15 ± 0.02, 0.95 ± 0.02 vs. 0.17 ± 0.01) ( P<0.05). RT-PCR was used to detect the expression of these five miRNAs in 15 COPD lung tissues, and the results showed that their expression was consistent with that in microarray. The prediction results of miRNA target genes showed that miR-206 could directly inhibit the expression of PTEN. RT-PCR results showed that the expression of miR-206 in miR-206 transfected HASMCs was significantly higher than that in miR-NC transfected group(7.44 ± 0.51 vs. 4.02 ± 0.19), and miR-206 inhibitor could significantly inhibit the expression of miR-206 in cells (1.86 ± 0.32), the difference was statistically significant ( P<0.05); MTT and apoptosis experiments showed that miR-206 mimcs could significantly promote the proliferation rate of cells compared with normal HASMCs or miR-NC transfected cells (0.62 ± 0.14 or 0.57 ± 0.09 vs. 0.83 ± 0.05), inhibit cell apoptosis (9.13 ± 1.71 or 10.02 ± 1.15 vs. 3.06 ± 0.82), the differences were statistically significant ( P<0.05), while miR-206 inhibitor could significantly inhibit cell proliferation and promote cell apoptosis ( P<0.05) The results of cell cycle distribution showed that compared with HASMCs group, the proportion of cells in S phase and G2/M phase in miR-206 mimcs group increased significantly ( P<0.05), while the proportion of cells in S phase and G2/M phase in miR-206 inhibitor group decreased significantly ( P<0.05), and there was no significant difference in miR-NC group ( P>0.05). The results of Western blot showed that compared with normal HASMCs or miR-NC transfected cells, miR-206 mimcs could significantly upregulate the expression of cyclin D1 (0.43 ± 0.07 or 0.41 ± 0.02 vs. 0.63 ± 0.17), and cyclin B1 (0.47 ± 0.13 or 0.50 ± 0.09 vs. 0.79 ± 0.31), and inhibit the expression of PTEN (0.34 ± 0.10 or 0.29 ± 0.05 vs. 0.14 ± 0.02), cyclin p21 (0.34 ± 0.03 or 0.30 ± 0.05 vs. 0.11 ± 0.02), and apoptosis related protein caspase-3 (0.29 ± 0.03 or 0.31 ± 0.05 vs. 0.15 ± 0.03), the differences were statistically significant ( P<0.05). miR-206 inhibitor could significantly inhibit the expression of cyclin D1 and cyclin B1, and promote the expression of PTEN, cyclin p21 and caspase-3 ( P<0.05). Conclusions:In COPD patients, miR-206 could targeted inhibit the expression of PTEN protein in airway smooth muscle cells and regulate the progress of cell cycle, so as to up regulate the proliferation of cells and inhibit their apoptosis.

The role and mechanisms of fibulin-1 in senescence-related calcification of vascular smooth muscle cells / 中华老年医学杂志

Objective:To investigate the role and mechanisms of fibulin-1 in senescence-related calcification of rat vascular smooth muscle cells induced by high-concentrationphosphate treatment.Methods:From September 2020 to September 2021, rat primary vascular smooth muscle cells were extracted from the thoracic aorta and abdominal aorta of 10 male SD rats aged 6 to 8 weeks.Phosphate(2.5 mmol/L Pi)was used to stimulate the calcification of vascular smooth muscle cells(VSMCs)in a model of stress-induced senescence-related calcification.Cellular senescence was assessed by SA-β-gal staining.Cellular calcification was determined by alizarin red staining and quantification of calcium deposition.Phenotypic transformation indexes and the expression of fibulin-1 during the process of calcification were detected by Western blot.The expression of fibulin-1 in primary rat vascular smooth muscle cells was knocked down by siRNA, the expression of pSmad3 was detected by immunofluorescence, and the effects of fibulin-1 on phenotypic transformation indexes of smooth muscle cells were detected by Western blot.The cells were cultured with recombinant fibulin-1 while transforming growth factor beta(TGF-β)inhibitor A83-01 and pSmad3 inhibitor SIS3 were also added.The senescence and calcification indexes of smooth muscle cells were detected by Western blot.Results:In the stress-induced aging model with phosphate stimulation of calcification in rat VSMCs, the expression of fibulin-1 was up-regulated( t=11.20, P<0.01), the expressions of MHC and SM22α was down-regulated( t=7.97, P<0.01; t=10.27, P<0.01), and the expression of osteoblastic phenotype markers OPN and Bmp2 and senescence marker P53 was up-regulated( t=4.79, P<0.01; t=9.56, P<0.01; t=14.07, P<0.01). Knockdown of fibulin-1 attenuated the degree of senescence and calcium deposition in VSMCs( t=12.90, P<0.05)and decreased the expression of OPN, Bmp2 and P53( t=5.92, P<0.05; t=10.15, P<0.01; t=8.28, P<0.01), at the same time, and TGF-β and pSmad3 expression was inhibited( t=12.90, P<0.01; t=7.46, P<0.01). After the addition of TGF-β/ smad3 pathway inhibitors, the stimulatory effect of recombinant fibulin-1 on phenotypic transformation and senescence protein expression inVSMCs was significantly reduced( t=4.52, P<0.01; t=9.82, P<0.01; t=3.85, P<0.05). Conclusions:Fibulin-1 can promote aging-related calcification of vascular smooth muscle cells through the TGF-β/smad3 signaling pathway.

Research advances on clinical evaluation of vascular aging / 中华老年医学杂志

Vascular senescence is one of the important causes of cardiovascular diseases.Functional evaluation of vascular endothelial cells and smooth muscle cells is an important means to identify vascular senescence.A convenient and effective vascular senescence assessment method applicable to clinical practice can identify high-risk populations early and is of great significance to the prevention, treatment and prognosis evaluation of related diseases.

Interleukin-1β mediates the effect of macrophage androgen receptor on hyperphosphate-induced vascular smooth muscle cell calcification / 中华肾脏病杂志

Objective:To investigate whether it is by regulating interleukin 1β ( IL-1β) gene expression that androgen receptor (AR) in macrophages affects hyperphosphate-induced vascular smooth muscle cell calcification. Methods:The chromatin immunoprecipitation (ChIP) experiment was used to determine whether AR was bound to the androgen receptor element (ARE) sequence of IL-1β promoter in THP-1 cells. Whether the AR regulated IL-1β gene expression was detected by luciferase assay experiments. AR of THP-1 cells was silenced and transfected by lentivirus with vector or shRNA. Flow cytometry was used to select positive transfected cells THP-1ARsc (control) and THP-1ARsi (AR silencing) with fluorescent markers. Western blotting was used to detect AR protein levels of THP-1ARsc (control) and THP-1ARsi cells (AR silencing in monocytes). Macrophages MФARsc (control) or MФARsi (AR silencing) were induced by 50 ng/ml phorbol ester. Enzyme-linked immunosorbent assay was used to detect IL-1β expression levels of MФARsc or MФARsi conditioned medium. The human aortic smooth muscle cells (HASMC) were cultured in MФARsc or MФARsi conditioned medium with phosphate (2.5 mmol/L final concentration of sodium dihydrogen phosphate), and Alizarin red S staining was used to analyze HASMC calcification degree. Western blotting was used to detect the expression levels of RUNX2 (osteoblast marker) and SM22α (HASMC marker), and neutralization assay was performed to test IL-1β-mediating effect of macrophages AR on HASMC calcification. Results:AR was bound to ARE sequence of IL-1β promoter and regulated IL-1β gene expression. The expression level of IL-1β protein in conditioned medium of MФARsi cells decreased significantly compared to MФARsc cells ( P<0.001). Compared with MФARsc conditioned medium group, HASMC calcium deposition in MФARsi conditioned medium group decreased significantly, RUNX2 protein decreased and SM22α protein increased (all P<0.05). The degree of HASMC calcification in the MФARsi conditioned medium+IgG antibody group decreased than that in the MФARsc conditioned medium+IgG antibody group significantly, and the degree of HASMC calcification in the MФARsc conditioned medium+IL-1β antibody group decreased significantly than that in the MФARsc conditioned medium+IgG antibody group; while the degree of HASMC calcification in the MФARsi conditioned medium+IgG antibody group and MФARsi conditioned medium+IL-1β antibody group decreased than that in the MФARsc conditioned medium+IL-1β antibody group (all P<0.05). Conclusions:Macrophage AR regulates IL-1β expression by binding to ARE sequence within IL-1β promoter, and IL-1β mediates the effect of macrophage AR on hyperphosphate-induced HASMC calcification.

Atorvastatina Reduz o Acúmulo de Células Musculares Lisas Vasculares para Inibir a Hiperplasia Intimal pela Inibição de Via p38 MAPK em um Modelo de Enxerto de Veia em Ratos / Atorvastatin Reduces Accumulation of Vascular Smooth Muscle Cells to Inhibit Intimal Hyperplasia via p38 MAPK Pathway Inhibition in a Rat Model of Vein Graft

Resumo Fundamento: A taxa de falha de enxerto de veia safena um ano após a cirurgia de revascularização do miocárdio varia de 10% a 25%. O objetivo deste estudo foi de investigar se a atorvastatina pode reduzir o acúmulo de células musculares lisas vasculares para inibir a hiperplasia intimal por meio da inibição da via p38 MAPK. Métodos: Quarenta e cinco ratos Sprague-Dawley foram randomizados em três grupos. Trinta ratos foram submetidos à cirurgia de enxerto de veia e randomizados para tratamento com veículo ou atorvastatina; quinze ratos foram submetidos à cirurgia sham. Detectamos a hiperplasia intimal por meio de coloração com hematoxilina-eosina e a expressão de proteínas relacionadas por meio de análise imuno-histoquímica e Western blot. Foram realizadas as comparações por análise de variância de fator único e pelo teste da diferença mínima significativa de Fisher, com p < 0,05 considerado significativo. Resultados: A íntima analisada pela coloração com hematoxilina-eosina era dramaticamente mais espessa no grupo controle que no grupo atorvastatina e no grupo sham (p < 0,01). Os resultados da coloração imuno-histoquímica de α-SMA demonstraram que a porcentagem de células positivas para α-SMA no grupo controle era mais alta que no grupo atorvastatina (p < 0,01). Nós também avaliamos α-SMA, PCNA, p38 MAPK e fosforilação de p38 MAPK após o tratamento com estatina por meio de análise de Western blot e os resultados indicaram que a atorvastatina não levou à redução de p38 MAPK (p < 0,05); no entanto, resultou na inibição da fosforilação de p38 MAPK (p < 0,01) e reduziu significativamente os níveis de α-SMA e PCNA, em comparação com o grupo controle (p < 0,01). Conclusão: Nós demonstramos que a atorvastatina pode inibir o acúmulo de células musculares lisas vasculares por meio da inibição da via p38 MAPK e é capaz de inibir a hiperplasia intimal em modelos de enxerto de veia em ratos.

Abstract Background: The rate of saphenous vein graft failure one year after coronary artery bypass grafting ranges from 10% to 25%. The aim of this study was to explore whether atorvastatin can reduce accumulation of vascular smooth muscle cells to inhibit intimal hyperplasia via p38 MAPK pathway inhibition. Methods: Forty-five Sprague-Dawley rats were randomized to three groups. Thirty rats received a vein graft operation, and they were randomized to be treated with vehicle or atorvastatin; fifteen rats received a sham operation. We detected intimal hyperplasia by hematoxylin-eosin staining and related protein expression by immunohistochemical and Western blot analysis. Comparisons were analyzed by single-factor analysis of variance and Fisher's least significant difference test, with p < 0.05 considered significant. Results: The intima analyzed by hematoxylin-eosin staining was dramatically thicker in the control group than in the atorvastatin group and sham group (p < 0.01). The outcomes of immunohistochemical staining of α-SMA demonstrated that the percentage of α-SMA-positive cells in the control group was higher than in the atorvastatin group (p < 0.01). We also evaluated α-SMA, PCNA, p38 MAPK, and phosphorylation of p38 MAPK after statin treatment by Western blot analysis, and the results indicated that atorvastatin did not lead to p38 MAPK reduction (p < 0.05); it did, however, result in inhibition of p38 MAPK phosphorylation (p < 0.01), and it significantly reduced α-SMA and PCNA levels, in comparison with the control group (p < 0.01). Conclusion: We have demonstrated that atorvastatin can inhibit accumulation of vascular smooth muscle cells by inhibiting the p38 MAPK pathway, and it is capable of inhibiting intimal hyperplasia in a rat vein graft model.

Cbfa1 expression in vascular smooth muscle cells may be elevated by increased nitric oxide/iNOS / A expressão de Cbfa1 nas células do músculo liso vascular pode ser elevada pelo aumento do óxido nítrico/iNOS

ABSTRACT Introduction: Vascular calcification is a common complication of chronic kidney disease. Osteoblast differentiation factor (Cbfa1) is present in histologic sections of arteries from patients with end-stage renal disease. Vascular smooth muscle cells (VSMC) can dedifferentiate to osteoblast-like cells, possibly by up-regulation of Cbfa1. There is evidence that the production of nitric oxide (NO) may have an important role in the regulation of osteoblast metabolism. The aim of this study is to evaluate whether increased NO/iNOS expression causes an increase in cbfa1 expression in VSMC. Methods: VSMC were obtained from renal artery of Wistar male rats, treated for 72 hours with lipopolysaccharide (LPS), ß-glycerophosphate (BGF), a donor of phosphate and aminoguanidine (AG), an inhibitor of iNOS, in the following groups: CTL (control), LPS, BGF, LPS + BGF, and LPS + AG. NO synthesis was determined by chemiluminescence. Cbfa1 and iNOS mRNA expressions were analyzed by RT-PCR, Cbfa1 protein expression by immunohistochemistry and cellular viability by acridine orange. Results: Cbfa1 and iNOS mRNA expressions were higher in LPS and LPS+ BGF vs CTL (p < 0.05), and they were lower in LPS+AG vs LPS (p < 0.05). The Cbfa1 in the groups LPS and LPS+BGF also resulted in a higher value compared to CTL (p < 0.05), and in LPS+AG it was lower compared to LPS (p < 0.05). NO was higher in LPS and LPS+BGF compared to CTL group (p < 0.05) and lower in LPS + AG compared to LPS group (p < 0.05). Cellular viability showed no statistical difference among groups. Conclusion: This study showed that increased NO/iNOS expression causes an increase in cbfa1 expression in VSMC.

RESUMO Introdução: A calcificação vascular é uma complicação comum da doença renal crônica. O fator de diferenciação osteoblástica (Cbfa1) está presente em cortes histológicos das artérias de pacientes com doença renal em estágio terminal. As células do músculo liso vascular (CMLV) podem desdiferenciar para células do tipo osteoblastos, possivelmente pela regulação positiva da Cbfa1. Há evidências de que a produção de óxido nítrico (NO) pode ter um papel importante na regulação do metabolismo dos osteoblastos. O objetivo deste estudo é avaliar se o aumento da expressão de NO/iNOS causa um aumento na expressão de cbfa1 nas CMLV. Métodos: As CMLV foram obtidas da artéria renal de ratos machos Wistar, tratados por 72 horas com lipopolissacarídeo (LPS), ß-glicerofosfato (BGF), um doador de fosfato e aminoguanidina (AG), um inibidor da iNOS, nos seguintes grupos: CTL (controle), LPS, BGF, LPS + BGF e LPS + AG. A síntese de NO foi determinada por quimioluminescência. As expressões de mRNA de Cbfa1 e iNOS foram analisadas por RT-PCR, a expressão da proteína Cbfa1 por imunohistoquímica e viabilidade celular por laranja de acridina. Resultados: As expressões de mRNA de Cbfa1 e iNOS foram maiores em LPS e LPS + BGF v.s. CTL (p < 0,05) e menores em LPS + AG v.s. LPS (p <0,05). O Cbfa1 nos grupos LPS e LPS + BGF também resultou em um valor maior em comparação ao CTL (p < 0,05), e no LPS + AG foi menor em comparação ao LPS (p < 0,05). NO foi maior no LPS e LPS + BGF em comparação ao grupo CTL (p < 0,05) e menor no LPS + AG em comparação ao grupo LPS (p < 0,05). A viabilidade celular não mostrou diferença estatística entre os grupos. Conclusão: Este estudo mostrou que o aumento da expressão de NO/iNOS causa um aumento na expressão de cbfa1 nas CMLV.

Primary study on the mechanism of ductus arteriosus closure in rats: impact of aging pathway / 中华心血管病杂志

Objective: To explore the role and mechanism of aging pathway in patent ductus arteriosus closure of rats. Methods: Thirty outbreeding Sprague Dawley rats(20 females, 10-15 weeks old, 270-330 g) underwent random mating and conception. The primary Ductus Arteriosus smooth muscle cells (DASMCs) of pregnant 19 days(E19 group), 21 days(E21 group) and newborn(Day0 group) fetus were extracted and cultured. mRNA expression of cell senescence related markers p16, 21 and 53 genes in each group were detected by real-time fluorescent quantitative PCR(RT-PCR) after 48 hours culture. After hypoxic culture on DASMCs for 3 days, the DASMCs were divided into 3 groups: hypoxic control group(G0 group), 3 hours normal oxygen concentration treatment group(G3 group) and 6 hours normal oxygen concentration treatment group(G6 group). After intervention, mRNA expression of p16, 21 and 53 RT-PCR was detected. The DASMCs of newborn rats(Day0 group) were extracted and divided into 3 groups:low-oxygen culture control group, low-oxygen+siRNA culture group and normal oxygen concentration culture group. The DASMCs migration ability was tested experimentally by Transwell method. Result: The mRNA levels of p16, 21 and 53 in DASMCs were higher in E19 group than in Day0 group(all P<0.01), and the mRNA levels of p16, 21 and 53 in DASMCs were also higher in E21 group than those in Day0 group (all P<0.01). The mRNA levels of p16, 21 and 53 in DASMC were all higher in G0 group than those in G3 group (P<0.05 or 0.01), and the mRNA levels of p16, 21 and 53 in DASMCs were all higher in G0 group than those in G6 group (all P<0.01), and the mRNA levels of p16, 21 and 53 in DASMCs were all higher in G3 group than those in G6 group (all P<0.05). DASMCs migration ability of newborn rats was higher in normal oxygen concentration culture group than that in low-oxygen culture group (P<0.01), and DASMCs migration ability of newborn rats was also higher in low-oxygen+siRNA culture group than that in low-oxygen culture group (P<0.01). Conclusion: The expression of senescence marker of DASMCs decreases with the birth in rats during the process of ductal closure, and the aging pathway may affect ductal closure by inhibiting DASMCs migration in rats.