Experimental observation on a new chimney-shaped mechanical valve completely implanted above the mitral annulus in animals.

Current commercially available prosthetic valves suffer from limited size, high requirements for implantation technique, subvalvular structural destruction, and valve dysfunction due to proliferation of fibrous endothelial tissue. This study aims to perform the preclinical large animal experiments for surgically implanting a chimney-shaped artificial mechanical heart valve with zero left ventricular occupancy, which fully accommodates the movement of the valve leaflets in the valve frame and realizes completely supra-annular surgical implantation. A total of 7 sheep underwent the replacement of artificial valve, and 5 sheep survived normally until anatomical examination. The mechanical properties of these artificial mitral valves remain functionally normal. There was no obvious thromboembolism around the artificial valve and in the important organs. The tissue layer of suture ring was completely organized and endothelialized, and the thickness of tissue layer was about 0.6-1.0 mm. The follow-up of echocardiography showed that the left ventricular ejection fraction was normal (60-70%) before and 6 months after operation. The results of transvalvular pressure gradient and blood flow velocity of artificial valve were normal. Left ventricular retrograde angiography showed that the artificial valve was completely located in the left atrium with good position and normal opening and closing. There was no obvious perivalvular leakage and other abnormalities. At 3 and 6 months, there were no obvious abnormalities in blood routine test, liver and kidney function, and other indexes. The new chimney-shaped artificial mechanical valve implanted completely above the mitral annulus had good wear resistance, histocompatibility, and antithrombotic and hemodynamic performance.

Outcomes of reoperation for total arch replacement combined with frozen elephant trunk after previous cardiovascular surgery.

BACKGROUND: Aortic arch replacement(TAR) combined with frozen elephant trunk (FET) technique is a high-risk operation after previous cardiovascular surgery. The aim of the study was to review our strategy and outcomes in this cohort. METHOD: Data were reviewed for patients who underwent TAR combined with FET after previous cardiovascular surgery from January 2010 to December 2020. The patients were divided into elective group and non-selective group. RESULTS: 63 eligible patients were divided into elective(n = 44) and non-elective(n = 19) groups. The interval between two operations was shorter in non-elective group than elective groups (P = 0.001). The indication for reoperation was different in two groups (P = 0.000), however, the type of reoperations has no differences. Cardiopulmonary bypass time was shorter in elective group than non-elective group (P = 0.000). The over-all 30-day mortality rate was 17.5%, and it was higher in non-elective group (P = 0.013). The 24h drainage increased in non-elective group (P = 0.001) as well as re-explore rate for bleeding (P = 0.022). Postoperative hospital stay prolonged in non-elective group (P = 0.002). However, rates of survival without further aortic events were 72.3 ± 7.1% in elective group, 72.9 ± 13.5% in non-elective group at 5 years, respectively (P = 0. 955). CONCLUSION: Reduced 30-day mortality and shortened post-operative hospital stay was observed in elective group, however, long-term survival rate without reintervention were not affected.

Molecular imaging of fibroblast activity in pressure overload heart failure using [68 Ga]Ga-FAPI-04 PET/CT.

PURPOSE: We aimed to evaluate whether [68 Ga]Ga-FAPI-04 PET/CT could characterize the early stages of cardiac fibrosis in pressure overload heart failure. METHODS: Sprague-Dawley rats underwent abdominal aortic constriction (AAC) (n = 12) and sham surgery (n = 10). All rats were scanned with [68 Ga]Ga-FAPI-04 PET/CT at 2, 4, and 8 weeks after surgery. The expression of fibroblast activation protein (FAP) in the myocardium was detected by immunohistochemistry. [68 Ga]Ga-FAPI-04 PET signal and FAP expression were compared between two groups. RESULTS: Compared with the sham group, the AAC group presented with decreased ejection fraction (EF) and fractional shortening (FS) and increased left ventricular internal dimensions in diastole (LVIDd) and systole (LVIDs) at 4 and 8 weeks (all p < 0.01). The AAC group showed higher [68 Ga]Ga-FAPI-04 accumulation in the heart than the sham group at 2, 4, and 8 weeks, and FAPI increased significantly from 2 to 8 weeks (all p < 0.001). Immunohistochemistry confirmed the higher density of the FAP+ area in the AAC group. The intensity of the [68 Ga]Ga-FAPI-04 correlated with the density of the FAP+ area (p < 0.001). The expression of the [68 Ga]Ga-FAPI-04 at 4 weeks correlated with the deterioration of cardiac function at 8 weeks (EF: R = - 0.87; FS: R = - 0.72; LVIDd: R = 0.77; LVIDs: R = 0.79; all p < 0.001). The AAC group also showed an increased [68 Ga]Ga-FAPI-04 signal in the liver, peaking at 4 weeks and then declining. Cardiac and liver PET signals correlated at 4 weeks in the AAC group (R = 0.69, p = 0.0010), suggesting an early fibrotic link between organs. A combination of the [68 Ga]Ga-FAPI-04 intensity in the heart and liver at 4 weeks better predicted the deterioration of cardiac function at 8 weeks. CONCLUSIONS: The activated fibroblasts in the heart and liver after pressure overload can be monitored by [68 Ga]Ga-FAPI-04 PET/CT, which reveals an early fibrotic link in cardio-liver interactions and could better predict nonischemic heart failure prognosis.

Therapeutic overexpression of miR-92a-2-5p ameliorated cardiomyocyte oxidative stress injury in the development of diabetic cardiomyopathy.

BACKGROUND: Diabetic cardiomyopathy (DCM) results from pathological changes in cardiac structure and function caused by diabetes. Excessive oxidative stress is an important feature of DCM pathogenesis. MicroRNAs (miRNAs) are key regulators of oxidative stress in the cardiovascular system. In the present study, we screened for the expression of oxidative stress-responsive miRNAs in the development of DCM. Furthermore, we aimed to explore the mechanism and therapeutic potential of miR-92a-2-5p in preventing diabetes-induced myocardial damage. METHODS: An experimental type 2 diabetic (T2DM) rat model was induced using a high-fat diet and low-dose streptozotocin (30 mg/kg). Oxidative stress injury in cardiomyocytes was induced by high glucose (33 mmol/L). Oxidative stress-responsive miRNAs were screened by quantitative real-time PCR. Intervention with miR-92a-2-5p was accomplished by tail vein injection of agomiR in vivo or adenovirus transfection in vitro. RESULTS: The expression of miR-92a-2-5p in the heart tissues was significantly decreased in the T2DM group. Decreased miR-92a-2-5p expression was also detected in high glucose-stimulated cardiomyocytes. Overexpression of miR-92a-2-5p attenuated cardiomyocyte oxidative stress injury, as demonstrated by increased glutathione level, and reduced reactive oxygen species accumulation, malondialdehyde and apoptosis levels. MAPK interacting serine/threonine kinase 2 (MKNK2) was verified as a novel target of miR-92a-2-5p. Overexpression of miR-92a-2-5p in cardiomyocytes significantly inhibited MKNK2 expression, leading to decreased phosphorylation of p38-MAPK signaling, which, in turn, ameliorated cardiomyocyte oxidative stress injury. Additionally, diabetes-induced myocardial damage was significantly alleviated by the injection of miR-92a-2-5p agomiR, which manifested as a significant improvement in myocardial remodeling and function. CONCLUSIONS: miR-92a-2-5p plays an important role in cardiac oxidative stress, and may serve as a therapeutic target in DCM.

KLF4 prevented angiotensin II-induced smooth muscle cell senescence by enhancing autophagic activity.

BACKGROUND: Vascular aging is an important risk factor for various cardiovascular diseases. Transcription factor krüppel-like factor 4 (KLF4) could regulate the phenotypic transformation of the vascular smooth muscle cell (VSMC) in the pathogenesis of aortic diseases. The present study aimed to explore the role and mechanism of KLF4 in angiotensin II (Ang II)-induced VSMC senescence. METHODS: The VSMC senescence mouse model was induced by sustained release of Ang II (1.0 µg/kg/min) for 4 weeks. The premature senescent VSMCs were induced by Ang II (0.1 µmol/L) for 72 h. Cellular senescence was measured by senescence-associated ß-galactosidase (SA-ß-gal) activity and p53/p16 expression. The autophagic activity was evaluated by autophagic flux and autophagic marker expression. RESULTS: The expression of KLF4 was extremely increased in abdominal aorta tissues after 1-week Ang II stimulation (p < .01) but began to decrease in later periods. Decreased expression of KLF4 was also detected in premature senescent VSMCs. Overexpression of KLF4 could enhance the antisenescence ability of VSMCs. Significantly decreased amounts of SA-ß-gal-positive cells and lower p53/p16 expression were detected in KLF4-overexpressing VSMCs (p < .01). Next, telomerase reverse transcriptase (TERT) was identified as a direct downstream target of KLF4 in VSMCs. Overexpression of KLF4 in VSMCs prevented the decreased expression of TERT under Ang II stimulation condition, which could in turn, contribute to the enhanced autophagic activity, and ultimately to the improved antisenescence ability of VSMCs. CONCLUSIONS: Our results demonstrated that overexpression of KLF4 prevented Ang II-induced VSMC senescence by promoting TERT-mediated autophagy. These findings provided novel potential targets for the prevention and therapy of vascular aging.

MicroRNA-22 promoted osteogenic differentiation of valvular interstitial cells by inhibiting CAB39 expression during aortic valve calcification.

Calcific aortic valve disease (CAVD) is a common valve disease characterized by the fibro-calcific remodeling of the aortic valves, which is an actively regulated process involving osteogenic differentiation of valvular interstitial cells (VICs). MicroRNA (miRNA) is an essential regulator in diverse biological processes in cells. The present study aimed to explore the role and mechanism of miR-22 in the osteogenic differentiation of VICs. The expression profile of osteogenesis-related miRNAs was first detected in aortic valve tissue from CAVD patients (n = 33) and healthy controls (n = 12). miR-22 was highly expressed in calcified valve tissues (P < 0.01), and the expression was positively correlated with the expression of OPN (rs = 0.820, P < 0.01) and Runx2 (rs = 0.563, P < 0.01) in VICs isolated from mild or moderately calcified valves. The sustained high expression of miR-22 was also validated in an in-vitro VICs osteogenic model. Adenovirus-mediated gain-of-function and loss-of-function experiments were then performed. Overexpression of miR-22 significantly accelerated the calcification process of VICs, manifested by significant increases in calcium deposition, alkaline phosphate activity, and expression of osteoblastic differentiation markers. Conversely, inhibition of miR-22 significantly negated the calcification process. Subsequently, calcium-binding protein 39 (CAB39) was identified as a target of miR-22. Overexpression of miR-22 significantly reduced the expression of CAB39 in VICs, leading to decreased catalytic activity of the CAB39-LKB1-STRAD complex, which, in turn, exacerbated changes in the AMPK-mTOR signaling pathway, and ultimately accelerated the calcification process. In addition, ROS generation and autophagic activity during VIC calcification were also regulated by miR-22/CAB39 pathway. These results indicate that miR-22 is an important accelerator of the osteogenic differentiation of VICs, and a potential therapeutic target in CAVD.

OCT4 regulated neointimal formation in injured mouse arteries by matrix metalloproteinase 2-mediated smooth muscle cells proliferation and migration.

The excessive proliferation and migration of vascular smooth muscle cells (VSMCs) play vital roles in neointimal hyperplasia and vascular restenosis. In the present study, we aimed to investigate the function and mechanism of octamer-binding transcription factor 4 (OCT4, a key transcription factor for maintaining stem cells in de-differentiated state) on neointima formation in response to vascular injury. Quantitative reverse-transcription polymerase chain reaction and western blot results displayed a significant increase of OCT4 levels in injured carotid arteries. Immunohistochemistry and immunofluorescence assays confirmed that the increased OCT4 expression was primarily localized in α-SMA-positive VSMCs from neointima, and colocalized with PCNA in the nuclei of VSMCs. Adenovirus-mediated OCT4 overexpression in injured carotid arteries exacerbated intimal thickening, while OCT4 knockdown significantly inhibited intimal thickening. In-vitro experiments confirmed that the increased OCT4 expression in VMSCs could be induced by platelet-derived growth factor-BB (PDGF-BB) in a time-dependent manner. Overexpression of OCT4 greatly promoted VSMCs proliferation and migration, while OCT4 knockdown significantly retarded the PDGF-BB-induced excessive proliferation and migration of VSMCs. Bioinformatics analysis, dual-luciferase reporter assay, and chromatin immunoprecipitation assay confirmed that OCT4 could upregulate matrix metalloproteinases 2 (MMP2) expression through promoting its transcription. Moreover, knockdown of MMP2 significantly attenuated OCT4-mediated VSMCs proliferation and migration. These results indicated that OCT4 facilitated neointimal formation in response to vascular injury by MMP2-mediated VSMCs proliferation and migration, and targeting OCT4 in VSMCs might be a novel therapeutic strategy for vascular restenosis.

Dysregulated long non-coding RNAs involved in regulation of matrix degradation during type-B aortic dissection pathogenesis.

Thoracic aortic dissection (TAD) is a catastrophic disease with the rupture of aortic media resulted mainly from the degradation of extracellular matrix. With the deep study of long non-coding RNAs (lncRNAs) in cardiovascular diseases, the correlation between lncRNAs and the TAD pathogenesis is under revealed. In this study, we aimed to screen the differentially expressed lncRNAs involved in the regulation of matrix degradation during type-B aortic dissection (TBAD), whose pathogenesis is more similar to atherosclerosis. A total of 393 aberrantly expressed lncRNAs and 432 aberrantly expressed mRNAs were identified in the descending aortic samples from TBAD patients. Then, co-expression analysis was applied to analyze the correlation between the top five differentially expressed lncRNAs and aberrantly expressed mRNAs, so as to screen the lncRNAs involved in the regulation of matrix degradation. The results showed that two transcripts from lnc-TNFSF14 (lnc-TNFSF14-2, and lnc-TNFSF14-3) were negatively interacted with MMP14 and MMP19. Subsequently, quantitative real-time PCR assay confirmed that lnc-TNFSF14-2 were negatively correlated with MMP14 (rs = - 0.8180) and MMP19 (rs = - 0.8449), and lnc-TNFSF14-3 was also negatively correlated with MMP14 (rs = - 0.7098) and MMP19 (rs = - 0.7728) in descending aorta from TBAD patients (n = 20). Overall, our study found the aberrant lncRNAs expression profiles in TBAD, and identified lnc-TNFSF14 as a potential target regulating matrix degradation. The results also provided crucial clues for lncRNAs function research on TBAD development.

All-Trans Retinoic Acid Prevented Vein Grafts Stenosis by Inhibiting Rb-E2F Mediated Cell Cycle Progression and KLF5-RARα Interaction in Human Vein Smooth Muscle Cells.

PURPOSE: Vein graft failure (VGF) is an important limitation for coronary artery bypass graft (CABG) surgery. Inhibition of the excessive proliferation and migration of venous smooth muscle cells (SMCs) is an effective strategy to alleviate VGF during the CABG perioperative period. In the present study, we aimed to explore the role and potential mechanism of all-trans retinoic acid (ATRA) on preventing vein grafts stenosis. METHODS: The autogenous vein grafts model was established in the right jugular artery of rabbits. Immunohistochemistry staining and western blot assays were used to detected the protein expression, while real-time PCR assay was applied for mRNAs expression detection. The interaction between proteins was identified by co-immunoprecipitation assay. The Cell Counting Kit-8 and wound-healing assays were used to investigate the role of ATRA on human umbilical vein smooth muscle cells (HUVSMCs) function. Cell cycle progression was identified by flow cytometry assay. RESULTS: Vein graft stenosis and SMCs hyperproliferation were confirmed in vein grafts by histological and Ki-67 immunohistochemistry assays. Treatment of ATRA (10 mg/kg/day) significantly mitigated the stenosis extent of vein grafts, demonstrated by the decreased thickness of intima-media, and decreased Ki-67 expression. ATRA could repress the PDGF-bb-induced excessive proliferation and migration of HUVSMCs, which was mediated by Rb-E2F dependent cell cycle inhibition. Meanwhile, ATRA could reduce the interaction between KLF5 and RARα, thereby inhibiting the function of cis-elements of KLF5. KLF5-induced inducible nitric oxide synthase (iNOS) expression activation could be significantly inhibited by ATRA. CONCLUSIONS: These results suggested that ATRA treatment may represent an effective prevention and therapy avenue for VGF.

Impact of a Higher Body Mass Index on Prolonged Intubation in Patients Undergoing Surgery for Acute Thoracic Aortic Dissection.

BACKGROUND: In recent years, obese patients presenting with acute thoracic aortic dissection have not been uncommon and there are often pulmonary complications among them. Whether a higher body mass index (BMI) is associated with more pulmonary complications or even a higher mortality rate has yet to be determined. This study aimed to evaluate the effects of higher BMI on pulmonary complications and other surgical outcomes. METHODS: A total of 404 patients who underwent acute thoracic aortic dissection surgery were retrospectively studied. They were divided into three groups based on their BMI: normal weight (BMI 18.5 to <25 kg/m2, n=173), overweight (BMI 25 to <30 kg/m2, n=145) and obese (BMI ≥30 kg/m2, n=86). Clinical data were collected and analysed among groups. RESULTS: No statistical significance was detected among the groups for postoperative complications, in-hospital mortality and hospital or ICU stay, except for prolonged intubation, the proportion of which was highest in the obese group followed by the overweight and normal groups (40.7% vs 29% vs 11%, respectively; p<0.001). Furthermore, logistic regression analysis showed that postoperative renal failure (OR=16.984) and cardiopulmonary bypass time (OR=1.013) were independent risk factors for in-hospital mortality, while higher BMI (OR=7.148 for BMI ≥25 and 18.967 for BMI ≥30), transfused red blood cells (OR=1.004), and postoperative renal failure (OR=7.386) were independent risk factors for prolonged ventilation (p<0.05). CONCLUSION: Body mass index had no effect on in-hospital mortality but may be closely correlated with prolonged intubation for patients undergoing aortic dissection surgery. This finding suggests that these patients should receive more aggressive pulmonary management.

Outcomes and risk factors of postoperative hepatic dysfunction in patients undergoing acute type A aortic dissection surgery.

BACKGROUND: Postoperative hepatic dysfunction (HD) increases the morbidity and mortality risk after cardiac surgery; however, only a few studies have specifically focused on acute type A aortic dissection (AAAD) surgery. We explored the possible risk factors and outcomes of early postoperative HD in patients with AAAD undergoing surgery. METHODS: All patients who underwent AAAD surgery at our institution from April 2015 to April 2017 were retrospectively evaluated. Postoperative model for end-stage liver disease (MELD) score was used to define HD. Independent risk factors for HD were determined by multivariate logistic analysis. RESULTS: Two hundred fifteen patients with AAAD met the inclusion criteria. The incidence rate of early postoperative HD was 60.9%, and the rate of in-hospital mortality was 16.8%. Patients with a high postoperative MELD score had longer mechanical ventilation time, longer durations of intensive care unit (ICU) stay, and higher in-hospital mortality. During the postoperative period, patients with AAAD complicated by HD needed continuous renal replacement therapy (CRRT), reintubation, tracheostomy, and blood transfusion more frequently. Aortic cross clamp (ACC) time [per 10 min higher; odds ratio (OR): 1.216, 95% confidence interval (CI): 1.017-1.454, P=0.032], postoperative leucocytes (per 2×109/L higher; OR: 1.161, 95% CI: 1.018-1.324, P=0.026), postoperative respiratory dysfunction (OR: 3.176, 95% CI: 1.293-7.803, P=0.012), and postoperative low cardiac output syndrome (LCOS) (OR: 12.663, 95% CI: 1.432-111.998, P=0.022) were independent risk factors associated with HD in patients undergoing AAAD surgery. CONCLUSIONS: Postoperative HD prolongs mechanical ventilation time and ICU stay, and is associated with increased in-hospital mortality among patients who undergo AAAD surgery. Several factors are associated with a high postoperative MELD score.

CALD1, CNN1, and TAGLN identified as potential prognostic molecular markers of bladder cancer by bioinformatics analysis.

BACKGROUND: Bladder cancer (BC) is one of the most common malignant neoplasms in the genitourinary tract. We employed the GSE13507 data set from the Gene Expression Omnibus (GEO) database in order to identify key genes related to tumorigenesis, progression, and prognosis in BC patients. METHODS: The data set used in this study included 10 normal bladder mucosae tissue samples and 165 primary BC tissue samples. Differentially expressed genes (DEGs) in the 2 types of samples were identified by GEO2R. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed using the online website DAVID. The online website STRING was used to construct a protein-protein interaction network. Moreover, the plugins in MCODE and cytoHubba in Cytoscape were employed to find the hub genes and modules in these DEGs. RESULTS: We identified 154 DEGs comprising 135 downregulated genes and 19 upregulated genes. The GO enrichment results were mainly related to the contractile fiber part, extracellular region part, actin cytoskeleton, and extracellular region. The KEGG pathway enrichment results mainly comprised type I diabetes mellitus, asthma, systemic lupus erythematosus, and allograft rejection. A module was identified from the protein-protein interaction network. In total, 15 hub genes were selected and 3 of them comprising CALD1, CNN1, and TAGLN were associated with both overall survival and disease-free survival. CONCLUSION: CALD1, CNN1, and TAGLN may be potential biomarkers for diagnosis as well as therapeutic targets in BC patients.

Inhibition of maternally expressed gene 3 attenuated lipopolysaccharide-induced apoptosis through sponging miR-21 in renal tubular epithelial cells.

Acute kidney injury (AKI) results in retention of waste products and dysregulation of extracellular volume and electrolytes, thus leading to a variety of complications. Recent advances in long noncoding RNAs suggested their close relationship with disease progression. In the current study, we investigated the role and mechanism of maternally expressed gene 3 (MEG3) on AKI pathogenesis. Real-time polymerase chain reaction found that the expression of MEG3 was significantly increased in both kidney tissues and TKPTS cells induced by lipopolysaccharide (LPS). Western blot assay showed that the expression of apoptosis regulator Bcl-2 was increased in MEG3-inhibited TKPTS cells. Flow cytometry assay confirmed that LPS-induced apoptosis was significantly attenuated after transfection of si-MEG3. The RNAhybrid informatics algorithm predicted that there was a strong binding capacity between miR-21 and MEG3. Luciferase reporter assay confirmed that MEG3 could function as a competing endogenous RNA of miR-21. The antiapoptotic effect of si-MEG3 could be neutralized by a miR-21 inhibitor, demonstrated by the decreased expression of Bcl-2 and flow cytometry results. Further investigation showed that programmed cell death protein 4 (PDCD4), a validated target of miR-21, was highly expressed in both injured kidney tissues and LPS-stimulated TKPTS cells. Meanwhile, the protein expression of PDCD4 was significantly reduced by inhibition of MEG3, but retrieved by coinhibition of MEG3 and miR-21. In conclusion, our results demonstrated that inhibition of MEG3 could attenuate LPS-induced apoptosis in TKPTS cells by regulating the miR-21/PDCD4 pathway, suggesting that the MEG3/miR-21/PDCD4 axis could be developed as a potential therapeutic target of AKI.

Circulating microRNAs: a novel potential biomarker for diagnosing acute aortic dissection.

Acute aortic dissection (AAD) is a catastrophic emergency with high mortality and misdiagnosis rate. We aimed to determine whether circulating microRNAs allow to distinguish AAD from healthy controls and chest pain patients without AAD (CP). Plasma microRNAs expression were determined in 103 participants, including 37 AAD patients, 26 chronic aortic dissection patients, 17 healthy volunteers, 23 patients without AAD. We selected 16 microRNAs from microarray screening as candidates for further testing via qRT-PCR. The results showed that plasma miR-15a in patients with AAD (n = 37) had significantly higher expression levels than it from control group (n = 40; P = 0.008). By receiver operating characteristic curve analysis, the sensitivity was 75.7%; the specificity was 82.5%; and the AUC was 0.761 for detection of AAD. Furthermore, 37 patients with AAD had significantly higher plasma expression levels of let-7b, miR-15a, miR-23a and hcmv-miR-US33-5p compared with 14 CP patients of 40 controls (P = 0.000, 0.000, 0.026 and 0.011, respectively). The corresponding sensitivity were 79.4%, 75.7%, 91.9% and 73.5%, respectively; the specificity were 92.9%, 100%, 85.7% and 85.7%, respectively; and the AUCs of these microRNAs were 0.887, 0.855, 0.925 and 0.815, respectively. These data indicate that plasma miR-15a and miR-23a have promising clinical value in diagnosing AAD.

MicroRNA-22 Promoted Osteogenic Differentiation of Human Periodontal Ligament Stem Cells by Targeting HDAC6.

Stem cells transplantation is a promising therapy strategy for accelerating periodontal regeneration and reconstruction. Genetic modification could induce stem cells directional differentiation to facilitate recovery of physiological functions. In this study, we investigated the role and mechanism of miR-22 on human periodontal ligament stem cells (PDLSCs). First, a cellular model of osteogenic differentiation was first established by osteogenic inductive cocktail. Real-time PCR determined that expression of miR-22 was significantly increased during PDLSCs osteogenic differentiation. Alizirin red staining showed that overexpression of miR-22 in PDLSCs induced better mineralized nodule formation. Real-time PCR and Western blot further confirmed up-regulation of osteogenic genes Runx2 and OPN in miR-22-overexpressing PDLSCs. Conversely, inhibition of miR-22 delayed the process of PDLSCs osteogenic differentiation. Furthermore, Histone deacetylase 6 (HDAC6) was identified as a target gene of miR-22. Overexpression of miR-22 not only reduced the luciferase activity of the reporter containing the 3' untranslated region of HDAC6 mRNA, but also suppressed the endogenous protein expression of HDAC6. Rescue experiment showed that the promotion role of miR-22 in osteogenic differentiation could be relieved by overexpression of HDAC6. Meanwhile, overexpression of HDAC6 alone could also delay the osteogenic differentiation process. The results demonstrated that miR-22 promoted PDLSCs osteogenic differentiation by inhibiting HDAC6 expression, suggesting that miR-22 might be developed as a target of genetic modified stem cells therapy for periodontal diseases. J. Cell. Biochem. 118: 1653-1658, 2017. © 2017 Wiley Periodicals, Inc.

Involvement of Oct4 in the pathogenesis of thoracic aortic dissection via inducing the dedifferentiated phenotype of human aortic smooth muscle cells by directly upregulating KLF5.

OBJECTIVE: To investigate the expression of Oct4 in human thoracic aortic dissection (TAD) and the regulation mechanisms of Oct4 on phenotype transition of human aortic smooth muscle cells (HASMCs). METHODS: Aortic samples from TAD patients (n = 12) and organ donors (n = 6) were collected. qRT-PCR, western blot, and immunohistochemistry were performed to identify Oct4 expression in aortic media. Immunofluorescence was performed to analyze Oct4 expression in primary HASMCs. Oct4A and Oct4B isoforms were detected. Gain-of-function experiments were performed to determine the effects of Oct4 on HASMC phenotype transition. Chromatin immunoprecipitation, luciferase assay, and rescue experiments were performed to analyze mechanisms of Oct4 on HASMC phenotype transition. RESULTS: Oct4 expression levels, especially the Oct4A isoform, were significantly higher in TAD patients compared with normal controls. Notably, Oct4 presented a strong and strict nuclear localization in primary HASMCs of TAD patients but a mild and diffuse distribution in both cytoplasm and nucleus in the control group. Overexpression of Oct4 induced dedifferentiation of HASMCs characterized by decreased contractile proteins and elevated migration capability. Krüppel-like factor 5 (KLF5) was found to be a directly regulated target gene of Oct4 in HASMCs. Furthermore, downregulation of KLF5 significantly alleviated the effects of Oct4 on phenotype transition of HASMCs. CONCLUSIONS: Oct4 expression was significantly upregulated in aortic tissues and primary HASMCs of TAD patients. The increased Oct4 induced phenotype transition of HASMCs from the contractile type to the synthetic type by directly upregulating KLF5.

Brahma-related gene 1 inhibits proliferation and migration of human aortic smooth muscle cells by directly up-regulating Ras-related associated with diabetes in the pathophysiologic processes of aortic dissection.

OBJECTIVE: To elucidate the mechanisms of Brahma-related gene 1 (Brg1) involvement in the pathophysiologic processes of aortic dissection. METHODS: Seventeen dissecting, 4 dilated, and 10 healthy human aorta samples were collected. Expression of Brg1 in the medium of aorta was evaluated by quantitative real-time polymerase chain reaction, Western blot, and immunohistochemical staining, respectively. The regulation effect of Brg1 on proliferation and migration of human aortic smooth muscle cells (HASMCs) was analyzed in 3 ways: using cell counting, a migration chamber, and a wound scratch assay. A polymerase chain reaction array was used for screening potential target genes of Brg1. A chromatin immunoprecipitation assay was adopted for direct deoxyribonucleic acid-protein binding detection. RESULTS: Expression levels of Brg1 were increased in aortic dissection and aortic dilation patients. In vitro results indicated that overexpression of Brg1 inhibited proliferation and migration of HASMCs. The candidate proliferation- and migration-related Brg1 target gene found was Ras-related associated with diabetes (RRAD), expression levels of which were enhanced in dissecting aortic specimens. The direct regulation effect of Brg1 on RRAD was verified by chromatin immunoprecipitation assay results. Furthermore, down-regulating RRAD significantly alleviated the suppression effects of Brg1 on proliferation and migration of HASMCs. CONCLUSIONS: Our study illustrated that Brg1 inhibited the proliferation and migration capacity of HASMCs, via the mechanism of direct up-regulation of RRAD, thus playing an important role in the pathophysiologic processes of aortic dissection.

Protein disulfide isomerase homolog TrPDI2 contributing to cellobiohydrolase production in Trichoderma reesei.

The majority of the cysteine residues in the secreted proteins form disulfide bonds via protein disulfide isomerase (PDI)-mediated catalysis, stabilizing the enzyme activity. The role of PDI in cellulase production is speculative, as well as the possibility of PDI as a target for improving enzyme production efficiency of Trichoderma reesei, a widely used producer of enzyme for the production of lignocellulose-based biofuels and biochemicals. Here, we report that a PDI homolog, TrPDI2 in T. reesei exhibited a 36.94% and an 11.81% similarity to Aspergillus niger TIGA and T. reesei PDI1, respectively. The capability of TrPDI2 to recover the activity of reduced and denatured RNase by promoting refolding verified its protein disulfide isomerase activity. The overexpression of Trpdi2 increased the secretion and the activity of CBH1 at the early stage of cellulase induction. In addition, both the expression level and redox state of TrPDI2 responded to cellulase induction in T. reesei, providing sustainable oxidative power to ensure cellobiohydrolase maturation and production. The results suggest that TrPDI2 may contribute to cellobiohydrolase secretion by enhancing the capability of disulfide bond formation, which is essential for protein folding and maturation.

HSF1 and NF-κB p65 participate in the process of exercise preconditioning attenuating pressure overload-induced pathological cardiac hypertrophy.

Pathological cardiac hypertrophy, often accompanied by hypertension, aortic stenosis and valvular defects, is typically associated with myocyte remodeling and cardiac dysfunction. Exercise preconditioning (EP) has been proven to enhance the tolerance of the myocardium to cardiac ischemia-reperfusion injury. However, the effects of EP in pathological cardiac hypertrophy are rarely reported. 10-wk-old male Sprague-Dawley rats (n = 80) were randomly divided into four groups: sham, TAC, EP + sham and EP + TAC. Two EP groups were subjected to 4 weeks of treadmill training, and the EP + TAC and TAC groups were followed by TAC operations. The sham and EP + sham groups underwent the same operation without aortic constriction. Eight weeks after the surgery, we evaluated the effects of EP by echocardiography, morphology, and histology and observed the expressions of the associated proteins. Compared with the respective control groups, hypertrophy-related indicators were significantly increased in the TAC and EP + TAC groups (p < 0.05). However, between the TAC and EP + TAC groups, all of these changes were effectively inhibited by EP treatment (p < 0.05). Furthermore, EP treatment upregulated the expression of HSF1 and HSP70, increased the HSF1 levels in the nuclear fraction, inhibited the expression of the NF-κB p65 subunit, decreased the NF-κB p65 subunit levels in the nuclear fraction, and reduced the IL2 levels in the myocardia of rats. EP could effectively reduce the cardiac hypertrophic responses induced by TAC and may play a protective role by upregulating the expressions of HSF1 and HSP70, activating HSF1 and then inhibiting the expression of NF-κB p65 and nuclear translocation.