Non-adherent culture method affects the proliferation and apoptosis of mesenchymal stem cells through inhibiting LINC00707 to promote RNF6-mediated QKI ubiquitination.

Exploration of the molecular mechanisms of mesenchymal stem cell (MSC) growth has significant clinical benefits. Long non-coding RNAs (lncRNAs) have been reported to play vital roles in the regulation of the osteogenic differentiation of MSCs. However, the mechanism by which lncRNA affects the proliferation and apoptosis of MSCs is unclear. In this study, sequencing analysis revealed that LINC00707 was significantly decreased in non-adherent human MSCs (non-AC-hMSCs) compared to adherent human MSCs. Moreover, LINC00707 overexpression promoted non-AChMSC proliferation, cell cycle progression from the G0/G1 phase to the S phase and inhibited apoptosis, whereas LINC00707 silencing had the opposite effect. Furthermore, LINC00707 interacted directly with the quaking (QKI) protein and enhanced the E3 ubiquitin-protein ligase ring finger protein 6 (RNF6)-mediated ubiquitination of the QKI protein. Additionally, the overexpression of QKI rescued the promotive effects on proliferation and inhibitory effects on apoptosis in non-AC-hMSCs induced by the ectopic expression of LINC00707. Thus, LINC00707 contributes to the proliferation and apoptosis in non-AChMSCs by regulating the ubiquitination and degradation of the QKI protein.

Single-Cell RNA-Seq Analysis Reveals Macrophages Are Involved in the Pathogenesis of Human Sporadic Acute Type A Aortic Dissection.

Macrophages play an important role in the progression of sporadic acute type A aortic dissection (ATAAD). The aim of this study was to characterize the cellular heterogeneity of macrophages in ATAAD tissues by scRNA-seq. Ascending aortic wall tissue from six ATAAD patients and three heart transplant donors was assessed by scRNA-seq and then analyzed and validated by various bioinformatic algorithms and histopathology experiments. The results revealed that the proportion of macrophages in ATAAD tissues (24.51%) was significantly higher than that in normal tissues (13.69%). Among the six macrophage subclusters, pro-inflammatory macrophages accounted for 14.96% of macrophages in the AD group and 0.18% in the normal group. Chemokine- and inflammation-related genes (CCL2, CCL20, S100A8, and S100A9) were expressed more intensively in macrophages in ATAAD tissue than in those in normal tissue. Additionally, intercellular communication analysis and transcription factor analysis indicated the activation of inflammation and degradation of the extracellular matrix in ATAAD tissue. Finally, immunohistochemistry, immunofluorescence, and Western blot experiments confirmed the overexpression of macrophage marker genes (CD68 and CD163) and matrix metalloproteinases (MMP9 and MMP2) in ATAAD tissue. Collectively, our study provides a preliminary evaluation of the role of macrophages in ATAAD, and the results could aid in the development of therapeutic options in the future.

Atypical location of primary cardiac lymphoma in the left heart with atypical clinical presentation: A case report and literature review.

Background: Primary cardiac lymphoma (PCL) is a rare and aggressive cardiac tumor with very poor prognosis that occurs mostly in the right cardiac cavity. Early diagnosis and treatment may improve its prognosis. In the present report, we describe the diagnosis and treatment of a primary cardiac diffuse large B-cell lymphoma (PC-DLBCL) with atypical location and clinical presentation. Additionally, a literature review was conducted to summarize the current knowledge of the disease. Case Presentation: A 71-year-old man visited his local hospital because of syncope, recurrent chest tightness, shortness of breath, palpitations, and profuse sweating for more than 20 days. Chest radiography revealed a mediastinal mass. Cardiac computed tomography (CT) showed multiple enlarged mediastinal lymph nodes. Transthoracic echocardiography (TTE) showed a cardiac mass in the posterior-inferior wall of the left atrium. He was then transferred to our hospital for positron emission tomography-CT (PET-CT) which showed active uptake of fluorodeoxyglucose both in the cardiac mass and in the multiple enlarged mediastinal lymph nodes. Biopsy of the enlarged mediastinal lymph nodes was carried out by using video-assisted thoracic surgery (VATS) technique, and pathological examination confirmed the subtype of PC-DLBCL, Stage IV, NCCN IPI 3. Therefore, the patient received a combination of chemotherapy and immunotherapy with R-CDOP (rituximab, cyclophosphamide, liposome doxorubicin, vincristine, and prednisone). After four courses of treatment in 4 months, the cardiac lymphoma and the enlarged mediastinal lymph nodes achieved complete remission with mild side effects of the chemotherapy. Conclusion: Early diagnosis and a precise choice of chemotherapy and immunotherapy based on cardiac imaging and pathological examination may improve the prognosis of PC-DLBCL in an atypical location.

Nonadherent culture method promotes MSC-mediated vascularization in myocardial infarction via miR-519d/VEGFA pathway.

BACKGROUND: Mesenchymal stem cells (MSCs) can provide therapeutic benefits for myocardial infarction (MI) recovery; however, the molecular mechanism by which MSCs improve the heart function is unclear. METHODS: Microarray analysis was performed to examine the expression profiling of human MSCs (hMSCs) grown as adherent cultures (AC-hMSCs) or nonadherent cultures on ultra-low-adherent plates (nonAC-hMSCs). Real-time quantitative polymerase chain reaction (RT-qPCR), western blotting, and enzyme-linked immunosorbent assays (ELISA) were used to assess VEGFA expression and secretion in the AC-hMSCs and nonAC-hMSCs. The paracrine effect of VEGFA-overexpressing AC-MSCs (AC-VEGFA-hMSCs) or VEGFA-knockdown nonAC-hMSCs (nonAC-shVEGFA-hMSCs) on the angiogenic ability of human umbilical vein endothelial cells (HUVECs) was evaluated using tube formation assay. AC-VEGFA-hMSCs or nonAC-shVEGFA-hMSCs were transplanted into myocardial infarction rats to investigate the therapeutic effect of AC-VEGFA-hMSCs or nonAC-shVEGFA-hMSCs. Luciferase reporter assay was used to confirm the association of VEGFA with miR-519d. RESULTS: Microarray analysis revealed that VEGFA is downregulated in AC-hMSCs compared to nonAC-hMSCs. Functional assays revealed that high levels of VEGFA produced from AC-VEGFA-hMSCs increased the tube formation capacity of HUVECs in vitro, improved angiogenesis and cardiac performance, and reduced infarct size in a rat MI model. Low levels of VEGFA secretion from nonAC-shVEGFA-hMSCs had the opposite effects. Mechanistically, we found that miR-519d directly targets VEGFA. High levels of VEGFA secreted from VEGFA-overexpressing nonAC-hMSCs abolished the repressive effect of miR-519d on HUVEC angiogenesis. CONCLUSION: Our findings indicate that nonadherent culture-induced secretion of VEGFA plays an important role in MSCs via the miR-519d/VEGFA pathway and may provide a novel therapeutic strategy for MI treatment.

Cysteinyl leukotriene receptor 1 regulates glucose-stimulated insulin secretion (GSIS).

Insulin resistance is an important pathological hallmark of type 2 diabetes mellitus. Glucose-stimulated insulin secretion (GSIS) plays a key role in maintaining blood glucose levels within normal range. Impaired GSIS has been associated with type 2 diabetes, however, the underlying molecular mechanisms remain largely unknown. Cysteinyl leukotriene receptor 1 (cysLT1R) is an important G protein-coupled receptor mediating the biological functions of cysteinyl leukotrienes (cys-LTs). Little is known about the effects of cysLT1R in insulin secretion and pathogenesis of T2DM. In the present study, we aimed to define the physiological functions of cysLT1R in GSIS in MIN6 ß-cells. Using reverse transcription polymerase chain reaction (RT-PCR) and western blot analysis, we found that cysLT1R was expressed in pancreatic MIN6 ß-cells. We also reported that glucose increased the expression of cysLT1R in MIN6 cells. Additionally, the cysLT1R antagonist montelukast promoted GSIS in a dose dependent manner, however, the cysLT1R agonist LD4 inhibited GSIS, suggesting an antagonistic effect of cysLT1R on GSIS. Silencing of cysLT1R by transfection with cysLT1R siRNA enhanced GSIS while overexpression of cysLT1R reduced GSIS in pancreatic MIN6 ß-cells. Mechanistically, we found that the Arf6/Cdc42/Rac1 pathway was involved in this process. Collectively, our findings highlight the essential role of cysLT1R in suppressing pancreatic insulin secretion, and potentially provided a new insight into understanding the mechanical regulation of glucose homeostasis.

Removal from adherent culture contributes to apoptosis in human bone marrow mesenchymal stem cells.

Mesenchymal stem cells (MSCs) are routinely isolated due to their adherence to tissue culture plates and their in vitro growth characteristics. Expansion of MSCs in adherent cultures is the only way to obtain sufficient cells for use in either clinical or research settings. MSCs have tremendous potential in myocardial repair treatment by cell therapy techniques, however, a large number of MSCs die from apoptosis following transplantation. Previous studies have examined the factors contributing to the survival of transplanted cells, but little is known about the effect of removal from adherent culture conditions on apoptosis of the MSCs. In the present study, human bone marrow MSCs were expanded in adherent cultures. Then apoptosis rates were examined at different time points in MSCs cultured in nonadherent conditions (ultra­low­adherence plates) compared with MSCs cultured in adherent conditions (standard tissue culture plates). Flow cytometry analysis suggested that cell apoptosis increased when MSCs were cultured in nonadherent culture conditions. In addition, western blot and reverse transcription­quantitative polymerase chain reaction analyses demonstrated that caspase­3, ­7 and ­9 were involved in this process. The present study demonstrated that loss of culture adherence increases apoptosis of human MSCs. The present findings may provide new insight into the factors affecting MSC survival after transplantation.

The Interactive Effects of Impulsivity and Negative Emotions on Adolescent Nonsuicidal Self-injury: A Latent Growth Curve Analysis.

This study employed latent growth curve analysis to evaluate the interactive effects of two specific facets of impulsivity (i.e., negative urgency [NU] and premeditation [PRE]) and negative emotions (NE) on the developmental trajectory of nonsuicidal self-injury (NSSI) among 3,453 (57% females) Chinese community adolescents. Participants completed questionnaires assessing NSSI, NU, PRE, and NE (i.e., depression, anxiety, and stress) at three waves of time. The initial levels of NE and NU significantly predicted the initial level of NSSI. Changes in NE and NU significantly predicted change in NSSI. Moreover, the initial levels of NU and PRE significantly moderated the relationship between the initial levels of NE and NSSI, such that among individuals with higher NU or less PRE, the three NE were associated with a higher level of NSSI. Additionally, among individuals with a faster increase in NU, depression and anxiety were associated with a faster increase in NSSI. These findings suggest that adolescents with trait impulsivity, especially in the form of NU, are more vulnerable to the engagement in NSSI.

Nonadherent culture method downregulates stem cell antigen-1 expression in mouse bone marrow mesenchymal stem cells.

Mesenchymal stem cells (MSCs) are primarily isolated by their adherence to plastic and their in vitro growth characteristics. Expansion of these cells from an adherent culture is the only method to obtain a sufficient number of cells for use in clinical practice and research. However, little is known with regard to the effect of adherence to plastic on the phenotype of the cells. In the present study, bone marrow CD45-CD31-CD44- stem cell antigen (Sca)-1+ MSCs were sorted by flow cytometry and expanded in adherent cultures. The expression levels of the adhesion molecule, Sca-1, in the adherent cultures were compared with those from nonadherent cultures at different time points. The flow cytometry results indicated that the expression levels of Sca-1 decreased in the MSCs in the nonadherent cultures grown in ultra-low-adherent plates. Furthermore, the result was confirmed by quantitative polymerase chain reaction at the same time points. Therefore, the results demonstrated that the loss of plastic adherence downregulated the expression of Sca-1. The observations may provide novel insights into the molecular mechanisms underlying plastic adherent culture.

Expression of miR-100 and RBSP3 in FTC-133 cells after exposure to 131I.

BACKGROUND: Sodium iodide ((131)I) therapy for the management of differentiated thyroid cancer is based on the deposition of certain doses of ionizing radiation, which can modulate microRNA (miRNA, miR) expression. Recent studies have suggested that miR-100 is significantly differentially expressed between benign and malignant thyroid tissue samples and modulates retinoblastoma 1 serine phosphates from human chromosome 3 (RBSP3), which is involved in the regulation of cell growth and differentiation. Therefore, the authors tested the hypothesis that a potential mechanism of (131)I treatment affects miR-100, which in turn regulates RBSP3 to modulate cell proliferation in thyroid cancer in vitro. MATERIALS AND METHODS: A follicular thyroid carcinoma cell line (FTC-133) was treated with (131)I or transfected with an oligonucleotide (miR-100 mimics, inhibitor, or negative control). Real-time quantitative PCR was used to confirm the expression levels of the miR-100 and RBSP3 mRNAs. Western blot analysis was performed to detect the levels of the RBSP3 protein. The cell cycle was analyzed on a cytofluorimeter by fluorescence-activated cell sorting analysis. RESULTS: RBSP3 protein expression was detected in FTC-133 cells. (131)I treatment inhibited the expression of miR-100 in FTC cells, as assessed by real-time quantitative PCR analysis, whereas it upregulated the RBSP3 mRNA and protein. Overexpression and knockdown experiments indicated that miR-100 repressed the expression of the RBSP3 mRNA by blocking its translation. Overexpression of miR-100 led to the downregulation of the RBSP3 protein and promoted the transition of FTC cells from the G1 to the S phase, as assessed using FACS analysis. CONCLUSION: (131)I treatment inhibited the expression of miR-100, which modulated RBSP3 in FTC cells. The new mechanism of suppression of the proliferation of FTC cells by I described here might occur through the downregulation of miR-100.