Effects of phentolamine on cardiac function, myocardial injury index, and hemodynamics in septic patients with myocardial injury / 中国基层医药

Objective:To investigate the efficacy of phenolamine in the treatment of sepsis-induced myocardial dysfunction and its effect on cardiac function, myocardial injury index, and hemodynamics in patients.Methods:The clinical data of 79 patients with sepsis-induced myocardial dysfunction who received treatment in Huangshi Central Hospital, Edong Healthcare Group from February 2017 to February 2020 were retrospectively analyzed. These patients were divided into a control group (without phenolamine treatment, n = 41) and an observation group (with phenolamine treatment, n = 38) according to whether they received phenolamine treatment or not. Clinical efficacy, cardiac function, myocardial injury index, and hemodynamic index pre- and post-treatment were compared between the two groups. Results:There was no significant difference in 28-day mortality rate between the two groups ( P > 0.05). Intensive care unit length of stay and mechanical ventilation duration in the observation group were (9.33 ± 3.52) days and 83.00 (28.50, 138.00) hours, which were significantly shorter than (12.17 ± 4.15) days and 111.00 (47.50, 169.00) hours in the control group ( t = 3.26, Z = -2.27, both P < 0.05). The response rate in the observation group was significantly higher than that in the control group [81.58% (31/38) vs. 60.98% (25/41), χ2 = 4.05, P < 0.05]. After 7 days of treatment, the left ventricular ejection fraction in each group was significantly increased, and the left ventricular end-diastolic diameter and left ventricular end-systolic diameter in each group were significantly decreased compared with before treatment (all P < 0.05). After 7 days of treatment, the left ventricular ejection fraction in the observation group was significantly higher than that in the control group ( t = 3.29, P < 0.05), and left ventricular end-diastolic diameter and left ventricular end-systolic diameter were significantly lower than those in the control group ( t = 5.94, 11.21, both P < 0.05). N-terminal pro-brain natriuretic peptide and cardiac troponin I levels in each group were significantly decreased with time (both P < 0.05). At 24 and 72 hours and 7 days after treatment, N-terminal pro-brain natriuretic peptide and cardiac troponin I levels in the observation group were significantly lower than those in the control group (both P < 0.05). After 7 days of treatment, heart rate in each group decreased significantly compared with that before treatment (both P < 0.05), mean arterial pressure, cardiac index, and stroke output index in each group increased significantly compared with those before treatment (all P < 0.05). After 7 days of treatment, heart rate in the observation group was significantly lower than that in the control group ( t = 4.90, P < 0.05), and mean arterial pressure, cardiac index, and stroke output index in the observation group were significantly higher than those in the control group ( t = 4.37, 3.23, 6.01, all P < 0.05). Conclusion:Phentolamine can improve hemodynamics, reduce myocardial injury and improve cardiac function in patients with sepsis-induced myocardial dysfunction.

Sevoflurane attenuates myocardial ischemia/reperfusion injury by up-regulating microRNA-99a and down-regulating BRD4

Purpose: It has been explored that sevoflurane (Sevo) is cardioprotective in myocardial ischemia/reperfusion injury (MI/RI) and mediates microRNA (miRNA) expression that control various physiological systems. Enlightened by that, the work was programmed to decode the mechanism of Sevo and miR-99a with the participation of bromodomain-containing protein 4 (BRD4). Methods: MI/RImodel was established on mice. MI/RI modeled mice were exposed to Sevo or injected with miR-99a or BRD4-related vectors to identify their functions in cardiac function, pathological injury, cardiomyocyte apoptosis, inflammation, and oxidative stress in MI/RI mice. MiR-99a and BRD4 expression in myocardial tissues were tested, and their relation was further validated. Results: MiR-99a was down-regulated, and BRD4 was up-regulated in MI/RI mice. Sevo up-regulated miR-99a to inhibit BRD4 expression in myocardial tissues of MI/RI mice. Sevo improved cardiac function, relieved myocardial injury, repressed cardiomyocyte apoptosis, and alleviated inflammation and oxidative stress in mice with MI/RI. MiR-99a restoration further enhanced the positive effects of Sevo on mice with MI/RI. Overexpression of BRD4 reversed up-regulation of miR-99a-induced attenuation of MI/RI in mice. Conclusions: The work delineated that Sevo up-regulates miR-99a to attenuate MI/RI by inhibiting BRD4.

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.

Avaliação Eletrocardiográfica de Recém-Nascidos Normais na Primeira Semana de Vida - Estudo Observacional / Electrocardiographic Evaluation of Normal Newborns in the First Week of Life - Observational Study

Resumo Fundamento O período neonatal é marcado por muitas alterações importantes no sistema cardiovascular, principalmente na primeira semana de vida. Diferentemente da população adulta, estudos sobre dados de eletrocardiograma (ECG) no período neonatal são escassos. Este é o primeiro estudo a descrever alterações eletrocardiográficas em uma coorte de recém-nascidos com ecocardiogramas normais. Objetivos Analisar padrões eletrocardiográficos de uma população de recém-nascidos a termo, sem anomalias morfológicas ou funcionais cardíacas, e comparar os resultados com a literatura. Métodos Neste estudo observacional, ecocardiogramas e resultados de ECG de 94 neonatos divididos em três grupos etários (até 24 horas, entre 25 e 72 horas, e entre 73 e 168 horas de vida) foram avaliados e comparados com aqueles descritos por Davignon et al. Um valor de p < 0,05 foi considerado estatisticamente significativo. Resultados Diferenças significativas na direção da onda T foram detectadas nas derivações V1 (p= 0,04), V2 (p= 0,02), V3 (p= 0,008) e V4 (p= 0,005). Houve diferenças entre nossos resultados e a literatura atual na maioria dos parâmetros. Conclusão Recém-nascidos a termo com menos de 24 horas de vida apresentaram significativamente mais ondas T positivas que aqueles com mais horas de vida. Encontramos muitas diferenças nos parâmetros de ECG em comparação aos descritos por Davignon et al., particularmente nas amplitudes de P, Q, R, S, duração do QRS, R/S e R+S. Esses achados indicam a necessidade de mais estudos para uma interpretação definitiva do ECG em recém-nascidos.

Abstract Background The neonatal period is marked by major changes in the cardiovascular system, especially in the first week of life. Unlike the adult population, studies on electrocardiogram (ECG) data in the neonatal period are scarce. This is the first study to describe electrocardiographic changes in a cohort of newborns with normal echocardiograms. Objectives To analyze the electrocardiographic patterns of a population of full-term NB, without any cardiac morphological or functional anomalies, and compare the results with the literature. Methods In this observational study, echocardiograms and ECG results from 94 newborns divided in three age groups (up to 24 hours, between 25 and 72 hours, and between 73 and 168 hours of life) were evaluated and compared with those reported by Davignon et al. A p-value <0.05 was considered statistically significant. Results There were significant differences in T-wave direction in leads V1 (p= 0.04), V2 (p= 0.02), V3 (p= 0.008) and V4 (p= 0.005) between the three age groups. There were differences between our findings and the current literature in most of the parameters. Conclusion Term newborns within 24 hours of life showed significantly more positive T waves than older ones. Many differences from the Davignon's ECG parameters were found, particularly in the P, Q, R, S amplitudes, QRS duration, R/S and R+S. These findings indicate that more studies are needed for a definitive interpretation of the ECG in newborns.

O Treinamento Físico Resistido Atenua as Disfunções Ventriculares Esquerdas em Modelo de Hipertensão Arterial Pulmonar / Resistance Exercise Training Mitigates Left Ventricular Dysfunctions in Pulmonary Artery Hypertension Model

Resumo Fundamento A hipertrofia e a dilatação do ventrículo direito observadas na hipertensão arterial pulmonar (HAP) prejudicam a dinâmica do ventrículo esquerdo (VE) achatando o septo interventricular. Objetivo Investigar se o treinamento físico resistido (TFR) de intensidade baixa a moderada é benéfico para funções contráteis do VE e de cardiomiócitos em ratos durante o desenvolvimento de HAP induzida por monocrotalina (MCT). Métodos Foram usados ratos Wistar machos (Peso corporal: ~ 200 g). Para avaliar o tempo até o possível surgimento de insuficiência cardíaca (ou seja, ponto de desfecho), os ratos foram divididos em dois grupos, hipertensão com sedentarismo até a insuficiência (HSI, n=6) e hipertensão com treinamento até a insuficiência (HTI, n=6). Para testar os efeitos do TFR, os ratos foram divididos entre grupos de controle sedentários (CS, n=7), hipertensão com sedentarismo (HS, n=7) e hipertensão com treinamento (HT, n=7). A HAP foi induzida por duas injeções de MCT (20 mg/kg, com um intervalo de 7 dias). Os grupos com treinamento foram submetidos a um protocolo de TFR (subir escadas; 55-65% da máxima carga carregada), 5 dias por semana. A significância estatística foi definida em p <0,05. Resultados O TFR prolongou o ponto de desfecho (~25%), melhorou a tolerância ao esforço físico (~55%) e atenuou as disfunções de contratilidade de VE e de cardiomiócitos promovidas pela MCT preservando a fração de ejeção e o encurtamento fracional, a amplitude do encurtamento, e as velocidades de contração e relaxamento nos cardiomiócitos. O TFR também preveniu os aumentos de fibrose e colágeno tipo I no ventrículo esquerdo causados pela MCT, além de manter as dimensões de miócitos e colágeno tipo III reduzidas por MCT. Conclusão O TFR de intensidade baixa a moderada é benéfico para funções contráteis de VE e cardiomiócitos em ratos durante o desenvolvimento de HAP induzida por MCT.

Abstract Background The right ventricular hypertrophy and dilation observed in pulmonary artery hypertension (PAH) damages the left ventricle (LV) dynamics by flattening the interventricular septum. Objective To investigate whether low- to moderate-intensity resistance exercise training (RT) is beneficial to LV and cardiomyocyte contractile functions in rats during the development of monocrotaline (MCT)-induced PAH. Methods Male Wistar rats (Body weight: ~ 200 g) were used. To assess the time to potential heart failure onset (i.e., end point), rats were divided into sedentary hypertension until failure (SHF, n=6) and exercise hypertension until failure (EHF, n=6) groups. To test RT effects, rats were divided into sedentary control (SC, n = 7), sedentary hypertension (SH, n=7), and exercise hypertension (EH, n=7) groups. PAH was induced by two MCT injections (20 mg/kg, with 7 days interval). Exercise groups were submitted to an RT protocol (Ladder climbing; 55-65% of carrying maximal load), 5 times/week. Statistical significance was assumed at P < 0.05. Results RT prolonged the end point (~25 %), enhanced the physical effort tolerance (~ 55%), and mitigated the LV and cardiomyocyte contractility dysfunctions promoted by MCT by preserving the ejection fraction and fractional shortening, the amplitude of shortening, and the velocities of contraction and relaxation in cardiomyocytes. RT also prevented increases in left ventricle fibrosis and type I collagen caused by MCT, and maintained the type III collagen and myocyte dimensions reduced by MCT. Conclusion Low- to moderate-intensity RT benefits LV and cardiomyocyte contractile functions in rats during the development of MCT-induced PAH.

Rapamycin and Paclitaxel Affect Human Aortic Smooth Muscle Cells-Derived Foam Cells Viability and Proliferation

Abstract Introduction: Drug-eluting stents (DES) coated with rapamycin or paclitaxel as antiproliferative substances significantly reduced the incidence of clinical restenosis and had fewer side effects after percutaneous coronary intervention. However, DES coated with rapamycin or paclitaxel still cause restenosis due to abnormal tissue growth which remained a therapeutic problem, particularly in certain subgroups, possibly due to drug concentrations. This study examined the impact of different concentrations of rapamycin and paclitaxel on cytokine, cell viability and proliferation in human aortic smooth muscle cells (HASMC)-derived foam cells. Methods: The foam cell model was established in vitro by incubating HASMC with 20 µg/mL oxidized low-density lipoprotein (ox-LDL) for 48 hours. Subsequently, foam cells were treated with different concentrations (0.01 µg/mL, 0.1 µg/mL, 0.5 µg/mL, 1 µg/mL, 5 µg/mL and 10 µg/mL) of rapamycin or paclitaxel for 48 hours, to measure cytokine, cell viability and proliferation by ELISA and MTT, respectively. Finally, viability and proliferation were measured by MTT after the foam cells were treated with 1 µg/mL rapamycin or paclitaxel combined with cytokine antibody for 48 hours. Results: After incubation of HASMC with ox-LDL, the ratios of cholesterol ester and total cholesterol increased significantly (55.29%) (P<0.01). Lipid staining with Oil Red O showed many lipid vacuoles and red dye particles in the cells. Meanwhile, cell viability and proliferation significantly increased compared with the control. This indicated that HASMC had been transformed into foam cells (P<0.01) while rapamycin or paclitaxel concentrations ≥0.1 µg/mL can significantly decrease the foam cell proliferation (P<0.05 or P<0.01), and 1 µg/mL of rapamycin or paclitaxel appeared the most effective concentration. As for cytokines, rapamycin or paclitaxel concentrations ≥1 ug/mL could significantly increase the level of inflammatory cytokines IL-6 (P<0.05 or P<0.01), which was enhanced with the increase of drug concentration. However, rapamycin or paclitaxel concentrations ≥1 µg/mL could significantly reduce the levels of anti-inflammatory cytokines IL-35 and transforming growth factor beta (TGF-β) (P<0.05 or P<0.01), which decreased with the increase of drug concentration. In addition, rapamycin or paclitaxel combined with anti-IL-1β, anti-IL-6, anti- TNF-α or anti-IL-35 had no significant effect on foam cell proliferation compared to the drug alone. However, rapamycin or paclitaxel combined with anti-IL-10 or anti-TGF-β can significantly enhance foam cell proliferation (P<0.01). In addition, there was no difference in the effects of the same concentrations of rapamycin and paclitaxel on foam cells. Conclusion: Although rapamycin or paclitaxel can reduce foam cell proliferation, too high or too low concentrations could decrease effectiveness. In particular, a high dose can induce foam cells to increase inflammatory cytokines secretion, reduce anti-inflammatory cytokines secretion, and thus affect the inhibiting proliferation. For rapamycin- and paclitaxel-eluting stents, this conclusion may explain the clinical observation of in-stent restenosis after percutaneous coronary intervention. DES coated with an appropriate concentration of rapamycin or paclitaxel may, at least to some extent, contribute significantly to reducing incidence of late in-stent restenosis.

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.

Effects of different densities of rat cardiac fibroblasts subjected to hypothermic hypoxia-reoxygenation on cardiomyocyte injury / 中华麻醉学杂志

Objective:To evaluate the effects of different densities of rat cardiac fibroblasts (RCF) subjected to hypothermic hypoxia-reoxygenation on cardiomyocyte injury and intercellular coupling.Methods:RCF was cultured in vitro and divided into 3 groups ( n=12 each) using a random number table method: RCF density 0.5×10 5 cells/ml group (T 0.5 group), RCF density 1.0×10 5 cells/ml group (T 1.0 group), and RCF density 2.0×10 5 cells/ml group (T 2.0 group). The three groups were placed in an anoxic device, into which 95% N 2 + 5% CO 2 was continuously blown at the speed of 5 L/min for 15 min, and then placed in a 4 ℃ refrigerator for 1 h for low temperature treatment.After completion of culture, cells were placed in a incubator containing 95% air + 5% CO 2 at 37 ℃ for 4 h of reoxygenation.After the end of culture, RCF in three groups were indirectly co-cultured with cardiomyocytes of the same density (1.0×10 5 cells/ml) in a Transwell chamber for 16 h, cardiomyocytes were seeded in the lower chamber of Transwell, and RCF were seeded in the upper chamber of Transwell.After the end of co-culture, cardiomyocytes were collected for determination of the cell viability (by CCK8 method), apoptosis rate (by flow cytometry), expression of connexin 43 (Cx43) mRNA (by real-time fluorescence quantitative polymerase chain reaction), and expression of Cx43 and phosphorylated Cx43 (p-Cx43) (by Western blot). Results:Compared with T 0.5 group, the cell viability, apoptosis rate and expression of Cx43, p-Cx43 and Cx43 mRNA were significantly decreased in T 1.0 and T 2.0 groups ( P<0.01). Compared with T 1.0 group, the cell viability, apoptosis rate and expression of Cx43 and p-Cx43 were significantly decreased ( P<0.01), and no significant change was found in expression of Cx43 mRNA in cardiomyocytes in T 2.0 group ( P>0.05). Conclusions:RCF subjected to hypothermic hypoxia-reoxygenation induces cardiomyocyte injury in a density-dependent manner in a certain range, and the mechanism may be related to down-regulation of the expression of Cx43 and reduction of the activity of Cx43.

Role of ferroptosis in hypoxia-reoxygenation injury in cardiomyocytes cultured in high-fat high-glucose medium / 中华麻醉学杂志

Objective:To evaluate the role of ferroptosis in hypoxia-reoxygenation (H/R) injury in cardiomyocytes cultured in high-fat high-glucose (HFHG) medium.Methods:Cardiomyocytes H9c2 cells were commonly cultured and divided into 3 groups ( n=20 each) using a random number table method: control group (C group), HFHG-H/R group and Ferrostatin-1 (Fer-1) plus HFHG-H/R group (Fer-1+ HFHG+ H/R group). H9c2 cells were cultured in a HFHG medium for 12 h and then exposed to 1%O 2-5%CO 2-94%N 2 for 4 h, followed by 2 h reoxygenation in a cell incubator.Fer-1 at a final concentration of 10 μmol/L was added while the cells were cultured in the HFHG medium in group Fer-1+ HFHG+ H/R.At 2 h of reoxygenation, the cell viability was measured using CCK-8 assay, the activity of lactate dehydrogenase (LDH) in the supernatant was measured using 2, 4-dinitrophenylhydrazine color method, the activity of reactive oxygen species (ROS) was measured by fluorescent probe DCFH-DA flow cytometry, and the expression of acyl-CoA synthetase long-chain family member 4 (ACSL4), nuclear receptor coactivator 4 (NCOA4), and glutathione peroxidase 4 (GPX4) was detected by Western blot. Results:Compared with group C, the cell viability was significantly decreased, the activities of LDH release and ROS were increased, and the expression of ACSL4 and NCOA4 was up-regulated ( P<0.05), and no significant change was found in the expression of GPX4 in group HFHG+ H/R ( P>0.05). Compared with group HFHG+ H/R, the cell activity was significantly increased, the activities of LDH and ROS were decreased, and the expression of ACSL4 and NCOA4 was down-regulated ( P<0.05), and no significant change was found in the expression of GPX4 in Fer-1+ HFHG+ H/R group ( P>0.05). Conclusions:Ferroptosis is involved in the process of H/R injury in cardiomyocytes cultured in HFHG medium.

Effect of rat cardiac fibroblasts on expression of Cx43 in H9c2 cells during hypothermic hypoxia/reoxygenation / 中华麻醉学杂志

Objective:To evaluate the effect of rat cardiac fibroblasts (RCF) on the expression of connexin43 (Cx43) in H9c2 cells during hypothermic hypoxia/reoxygenation.Methods:H9c2 cells cultured in vitro were divided into 4 groups ( n=12 each) using the random number table method: control group (group C), hypothermic hypoxia/reoxygenation group (group HHR), RCF co-culture group (group Co) and RCF co-culture plus hypothermic hypoxia/reoxygenation group (group Co+ HHR). Group C was incubated at 37℃ in 5% CO 2 + 95% air for 5 h. Group HHR was incubated at 4 ℃ in 5% CO 2 + 95% N 2 for 1 h and then at 37 ℃ in 5% CO 2 + 95% air for 4 h. In group Co and group Co+ HHR, H9c2 cells 0.3×10 5 cells/well were inoculated in the lower chamber and RCF 0.6×10 5 cells/well in the the upper chamber of a transwell ? culture dish.Group Co was incubated at 37 ℃ in 5% CO 2 + 95% air for 5 h. Group Co+ HHR was incubated at 4℃ in 95% N 2 + 5% CO 2 for 1 h, and then incubated at 37 ℃ in 5% CO 2 + 95% air for 4 h. The mortality rate of H9c2 cells was measured by trypan blue staining, the expression of Cx43 and extracellular signal-regulated protein kinases 1/2 (ERK1/2) by immunofluorescence, and the expression of Cx43, phosphorylated Cx43, ERK1/2 and phosphorylated ERK1/2 by Western blot. Results:Compared with group C, the mortality rate of H9c2 cells was significantly increased, the expression and phosphorylation of Cx43 were decreased, and the expression and phosphorylation of ERK1/2 were increased in group HHR ( P<0.05), and no significant change was found in the mortality rate of H9c2 cells or expression and phosphorylation of Cx43 and ERK1/2 in group Co ( P>0.05). Compared with group Co, the mortality rate of H9c2 cells was significantly increased, and the expression and phosphorylation of Cx43 and ERK1/2 were decreased in group Co+ HHR ( P<0.05). Compared with group HHR, the mortality rate of H9c2 cells was significantly increased, and the expression and phosphorylation of Cx43 and ERK1/2 were decreased in group Co+ HHR ( P<0.05). Conclusions:RCFs can decrease the expression and activity of Cx43 in H9c2 cells during hypothermic hypoxia/reoxygenation, and the mechanism may be related to the down-regulation of ERK1/2 expression and inhibition of ERK1/2 activity.

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.

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.

Role of reactive oxygen species in hypoxia postconditioning-induced activation of Nrf2/ARE signaling pathway in rat cardiomyocytes / 中华麻醉学杂志

Objective:To evaluate the role of reactive oxygen species (ROS) in hypoxia postconditioning-induced activation of nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathway in rat cardiomyocytes.Methods:Primary cardiomyocytes of adult rats were isolated and cultured and divided into 4 groups ( n=20 each) using a random number table method: normal group (group N), hypoxia-reoxygenation group (group HR), hypoxia postconditioning group (group HPO) and hypoxia postconditioning plus an ROS scavenger N-(2-Amidinopropionyl)-glycine (MPG) group (group HPO+ MPG). Cells were exposed to hypoxia for 45 min followed by 60 min reoxygenation to develop the cardiomyocyte hypoxia-reoxygenation injury model.In HPO group, cells were subjected to 3 cycles of 5-min hypoxia/5-min reoxygenation after 45 min hypoxia, followed by reoxygenation for 60 min.In HPO+ MPG group, MPG (final concentration 2 mmol/L) was added at 35 min of hypoxia, cells were subjected to hypoxia for 10 min, and the other treatments were similar to those previously described in group HPO.At the end of reoxygenation, the intracellular calcium level and Nrf2 activity were measured, the ultrastructure of cardiomyocytes was observed, and the Flameng score of mitochondria was assessed, and the expression of Nrf2, NAD(P)H quinine oxidoreductase 1 (NQO1), superoxide dismutase 1 (SOD1) and heme oxygenase-1 (HO-1) protein and mRNA was detected using real-time polymerase chain reaction and Western blot. Results:Compared with group N, the intracellular free Ca 2+ level, Nrf2 activity and Flameng score were significantly increased, and the expression of Nrf2, NQO1, SOD1 and HO-1 protein and mRNA was down-regulated in group HR ( P<0.05). Compared with group HR, the intracellular free Ca 2+ level and Flameng score were significantly decreased, the Nrf2 activity was increased, and the expression of Nrf2, NQO1, SOD1 and HO-1 protein and mRNA was up-regulated in group HPO ( P<0.05). Compared with group HPO, the intracellular free Ca 2+ level and Flameng score were significantly increased, the Nrf2 activity was decreased, and the expression of Nrf2, NQO1, SOD1 and HO-1 protein and mRNA was down-regulated in group HPO+ MPG ( P<0.05). Conclusions:The mechanism by which hypoxia postconditioning activates the Nrf2/ARE signaling pathway in rat cardiomyocytes may be related to ROS.

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.

Effect of aerobic and anaerobic training on different ergometers in rat muscle and heart tissues / Efeito dos treinamentos aeróbio e anaeróbio em diferentes ergômetros nos tecidos muscular e cardíaco de ratos

ABSTRACT Objective Analyze the effects of aerobic and anaerobic training on different ergometers on muscle and cardiac hypertrophy in rats. Methods The animals were separated into the following groups: Control (C), Aerobic Training in Water (ATW), Resistance Training in Water (RTW), Aerobic Training on Treadmill (ATT), and Resistance Training in Climbing (RTC). All training protocols were carried out for 4 weeks, 3 times/week. The cross-sectional area (CSA) of the gastrocnemius muscle cells and the areas of the cardiomyocytes were measured. Results In the fast-twitch fibers, there was an increase in CSA in the RTW and RTC groups compared to the ATW (p<0.01 and p<0.01) and ATT groups (p<0.01 and p<0.01). In the slow-twitch fibers, the ATW and ATT groups demonstrated a lower CSA compared to the RTW (p=0.03 and p<0.00) and RTC groups (p<0.01 and p<0.01). In the cardiomyocytes, there was an increase in the area of the RTW and RTC groups compared to groups C (p<0.01; p<0.01), ATW (p=0.02; p<0.01), and ATT (p<0.01; p<0.01). Conclusion The anaerobic training effectively promotes hypertrophy in the fast-twitch fibers and the cardiomyocytes. Level of Evidence V; Animal experimental study.

RESUMO Objetivo Analisar os efeitos dos treinamentos aeróbios e anaeróbios em diferentes ergômetros na hipertrofia muscular e cardíaca de ratos. Métodos Os animais foram separados nos grupos controle (C), treinamento aeróbio em natação (ATW), treinamento resistido em meio aquático (RTW), treinamento aeróbio em esteira rolante (ATT) e treinamento resistido em escalada (RTC). Os protocolos de treinamento foram realizados por 4 semanas, 3 x/semana. Foram mensurados a área de secção transversa (CSA) das células do músculo gastrocnêmio e as áreas dos cardiomiócitos. Resultados Nas fibras de contração rápida houve aumento da CSA dos grupos RTW e RTC em relação aos grupos ATW (p<0,01 e p<0,01) e ATT (p<0,01 e p<0,01). Nas fibras de contração lenta os grupos ATW e ATT demonstraram menor CSA comparado aos grupos RTW (p=0,03 e p<0,00) e RTC (p<0,01 e p<0,01). Nos cardiomiócitos houve aumento da área dos grupos RTW e RTC em comparação com os grupos C (p<0,01 e p<0,01), ATW (p=0,02 e p<0,01) e ATT (p<0,01 e p<0,01). Conclusão Os treinamentos anaeróbios promoveram hipertrofia nas fibras de contração rápida e nos cardiomiócitos. Nível de Evidência V; Estudo experimental em animais.

A Inibição do Metabolismo da Glicose por miR-34a e miR-125b Protege contra a Morte Celular de Cardiomiócitos Causada por Hiperglicemia / Inhibiting Glucose Metabolism By miR-34a and miR-125b Protects Against Hyperglycemia-Induced Cardiomyocyte Cell Death

Resumo Fundamento: É sabido que a resistência à insulina e a hiperglicemia são causas patológicas importantes no desenvolvimento de cardiomiopatia diabética (CMD). Entretanto, seus mecanismos moleculares precisos na patogênese da CMD ainda não estão claros. Objetivos: Estudos recentes revelam que os microRNAs (miRNAs) desempenham papéis essenciais na patogênese da CMD. Este projeto tem o objetivo de determinar os papéis de miR-34a e miR-125b na morte celular de cardiomiócitos causada por hiperglicemia. Métodos: Cardiomiócitos primários de ratos foram isolados e expostos a concentrações de glicose normais e altas. A viabilidade das células foi medida utilizando-se o ensaio MTT. As expressões de miR-34a e miR-125b foram detectadas por qRT-PCR. Alvos potenciais de miR-34a e miR-125b foram previstos pelo www.Targetscan.org, e validados a partir de tecidos cardíacos humanos. Um p<0,05 foi considerado significância estatística. Resultados: Demonstra-se neste estudo que o miR-34a e o miR-125b têm resposta celular reduzida no coração humano diabético. Além disso, os dados in vitro de cardiomiócitos primários de ratos demonstraram que o tratamento com glicose alta em curto prazo estimula a expressão de miR-34a e miR-125b. Demonstrou-se que, em condições de glicose alta, os cardiomiócitos de ratos apresentaram metabolismo de glicose intracelular, e a captação de glicose e a produção de lactato aumentaram significativamente. Foi identificado que as principais enzimas metabólicas da glicose, hexoquinase 2 (HK2) e lactato desidrogenase-A (LDHA) eram alvos diretos de miR-125b e miR-34a, respectivamente. A superexpressão de miR-125b e miR-34a poderia evitar a morte de celular de cardiomiócitos causada por hiperglicemia. Por fim, a recuperação de HK2 e LDHA em cardiomiócitos com superexpressão de miR-125b e miR-34a restaurou a sensibilidade de cardiomiócitos à hiperglicemia. Conclusões: Nossos resultados propõem um mecanismo molecular para proteção cardiovascular diabética mediada por microRNA e contribuirão para o desenvolvimento de estratégias de tratamento de disfunção cardiovascular associada a diabetes.

Abstract Background: It is well-known that insulin resistance and hyperglycemia are important pathological causes for the development of diabetic cardiomyopathy (DCM). However, its precise molecular mechanisms in the pathogenesis of DCM remain unclear. Objectives: Recent studies reveal that microRNAs (miRNA) play essential roles in the pathogenesis of DCM. This project aimed to determine the roles of miR-34a and miR-125b in hyperglycemia-induced cardiomyocyte cell death. Methods: Rat primary cardiomyocytes were isolated and exposed to normal and high concentrations of glucose. Cell viability was measured using MTT assay. Expressions of miR-34a and miR-125b were detected by qRT-PCR. Potential targets of miR-34a and miR-125b were predicted from www.Targetscan.org and validated from human heart tissues. A statistical significance of p<0.05 was considered. Results: The present study shows that miR-34a and miR-125b are downregulated in a human diabetic heart. Moreover, in vitro data from rat primary cardiomyocytes showed that short-term high glucose treatment stimulates miR-34a and miR-125b expressions. Under high glucose, it was found that rat cardiomyocytes displayed increased intracellular glucose metabolism, and glucose uptake and lactate production were significantly increased. It was also found that the key glucose metabolic enzymes, Hexokinase 2 (HK2) and Lactate dehydrogenase-A (LDHA), were direct targets of miR-125b and miR-34a, respectively. Overexpression of miR-125b and miR-34a could prevent hyperglycemia-induced cardiomyocyte cell death. Finally, the restoration of HK2 and LDHA in miR-125b and miR-34a overexpressed cardiomyocytes recovered the cardiomyocytes' sensitivity to hyperglycemia. Conclusion: Our results proposed a molecular mechanism for the microRNA-mediated diabetic cardiovascular protection and will contribute to developing treatment strategies for diabetes-associated cardiovascular dysfunction.

Role of HDAC3 in high glucose hypoxia/reoxygenation injury to primary rat cardiomyocytes: the relationship with autophagy / 中华麻醉学杂志

Objective:To evaluate the role of histone deacetylase 3 (HDAC3) in high glucose hypoxia/reoxygenation (H/R) injury to primary rat cardiomyocytes and the relationship with autophagy.Methods:The primary cardiomyocytes extracted from newborn Sprague-Dawley rats, aged about 1-3 days, were divided into 5 groups ( n=24 each) according to the random number table method: control group (C group, glucose concentration 5.5 mmol/L), H/R group, high glucose group (H group, glucose concentration 30 mmol/L), high glucose H/R group (HH/R group), and high glucose H/R + HDAC3 inhibitor RGFP966 group (HH/R+ RG group). Fifty percent glucose injection was used to prepare high-glucose medium (final concentration 30 mmol/L). Cells were cultured in a hypoxic environment (5% CO 2-0.9% O 2-94.1% N 2) for 6 h, followed by reoxygenation in a normoxic environment for 2 h to establish the cardiomyocyte H/R model in H/R group.RGFP966 at a final concentration of 10 μmol/L was added at 24 h before H/R in HH/R+ RG group.At 2 h of reoxygenation, the cell viability was measured using CCK-8 kit, the activity of lactic dehydrogenase (LDH) in the cell supernatant was determined using enzyme-linked immunosorbent assay, the level of autophagy was detected with a confocal microscope after cells were transfected with autophagy double-labeled adenovirus (mRFP-GFP-LC3), and the expression of HDAC3, p62, LC3 Ⅱ and LC3 Ⅰ was detected using Western blot.LC3Ⅱ/LC3Ⅰ ratio was calculated. Results:Compared with group C, the cell viability was significantly decreased, and the activity of LDH in supernatant was increased in H/R and H groups, the number of autophagosomes was significantly increased, the expression of HDAC3 in cardiomyocytes was up-regulated, the expression of p62 was down-regulated, and the LC3 Ⅱ/I ratio was increased in group H/R, and the number of autophagosomes was significantly decreased, the expression of HDAC3 and p62 in cardiomyocytes was up-regulated, and the LC3 Ⅱ/I ratio was decreased in group H ( P<0.05). Compared with group H/R, the cell viability was significantly decreased, the activity of LDH in supernatant was increased, the number of autophagosomes was decreased, the expression of HDAC3 and p62 in cardiomyocytes was up-regulated, and the LC3 Ⅱ/I ratio was decreased in group HH/R ( P<0.05). Compared with group H, the cell viability was significantly decreased, the activity of LDH in supernatant was increased, the number of autophagosomes was increased, the expression of HDAC3 and p62 in cardiomyocytes was up-regulated, and the LC3 Ⅱ/I ratio was increased in group HH/R ( P<0.05). Compared with group HH/R, the cell viability was significantly increased, the activity of LDH in supernatant was decreased, the number of autophagosomes was increased, the expression of HDAC3 and p62 in cardiomyocytes was down-regulated, and the LC3 Ⅱ/I ratio was increased in group HH/R+ RG ( P<0.05). Conclusion:Up-regulation of HDAC3 expression is involved in high glucose H/R injury to primary rat cardiomyocytes, which is related to decreasing the level of autophagy.

Effect of TBK1 overexpression on hypoxia-reoxygenation injury in isolated mouse cardiomyocytes subjected to high glucose: relationship with mitochondrial autophagy / 中华麻醉学杂志

Objective:To evaluate the effect of TBK1 overexpression on hypoxia-reoxygenation (H/R) injury in isolated mouse cardiomyocytes subjected to high glucose and the relationship with mitochondrial autophagy.Methods:Normally cultured log-phase HL-1 mouse cardiomyocytes were inoculated in a 6-well plate at a density of 1×10 6 cells/ml and were divided into 4 groups ( n=10 each) using a random number table method: control group (group C), high glucose group (group HG), high glucose and H/R group (group HG+ H/R), and TBK1 overexpression group (group TBK1). The cells were incubated in culture medium with 1% fetal bovine serum and 1% double antibody for 24 h when the cell density reached 50%.When the cell density reached 80%, pcDNA3.1 (+ ) was used as a vector to achieve TBK1 overexpression.The cells were cultured with high glucose medium (33 mmol/L) for 24 h, exposed to 94% N 2+ 5% CO 2+ 1% O 2 for 24 h in an incubator at 37℃ followed by 12 h reoxygenation in an incubator containing 5% CO 2 at 37°C to establish the model of H/R injury to cardiomyocytes subjected to high glucose.After reoxygenation, CCK-8 assay was used to detect cell viability, the activity of lactic dehydrogenase (LDH) in supernatant was detected using LDH kit, mitochondrial contents were determined using Mito-Tracter green fluorescent probe, and the expression of TBK1 and mitophagy-related proteins PINK1, Parkin, LC3B and P62 was detected by Western blot. Results:Compared with group C, the cell viability was significantly decreased, the activity of LDH in supernatant was increased, mitochondrial contents were decreased, the expression of TBK1, PINK1, Parkin and LC3B was down-regulated, and the expression of P62 was up-regulated in HG group and HG+ H/R group ( P<0.05). Compared with group HG, the cell viability was significantly decreased, the activity of LDH in supernatant was increased, mitochondrial contents were decreased, the expression of TBK1, PINK1, Parkin and LC3B was down-regulated, and the expression of P62 was up-regulated in group HG+ H/R ( P<0.05). Compared with group HG+ H/R, the the cell viability was significantly increased, the activity of LDH in supernatant was decreased, mitochondrial contents were increased, the expression of TBK1, PINK1, Parkin and LC3B was up-regulated, and the expression of P62 was down-regulated in group TBK1 ( P<0.05). Conclusion:The mechanism by which TBK1 overexpression reduces the H/R injury is related to restoring mitophagy in isolated mouse cardiomyocytes subjected to high glucose.