The long non-coding RNA CARDINAL attenuates cardiac hypertrophy by modulating protein translation

One of the features of pathological cardiac hypertrophy is enhanced translation and protein synthesis. Translational inhibition has been shown to be an effective means of treating cardiac hypertrophy, although system-wide side effects are common. Regulators of translation, such as cardiac-specific long non-coding RNAs (lncRNAs), could provide new, more targeted, therapeutic approaches to inhibit cardiac hypertrophy. Therefore, we generated mice lacking a previously identified lncRNA named CARDINAL to examine its cardiac function. We demonstrate that CARDINAL is a cardiac-specific, ribosome associated lncRNA and show that its expression is induced in the heart upon pathological cardiac hypertrophy; its deletion in mice exacerbates stress-induced cardiac hypertrophy and augments protein translation. In contrast, overexpression of CARDINAL attenuates cardiac hypertrophy in vivo and in vitro, and suppresses hypertrophy-induced protein translation. Mechanistically, CARDINAL interacts with developmentally regulated GTP binding protein 1 (DRG1) and blocks its interaction with DRG family regulatory protein 1 (DFRP1); as a result, DRG1 is downregulated, thereby modulating the rate of protein translation in the heart in response to stress. This study provides evidence for the therapeutic potential of targeting cardiac-specific lncRNAs to suppress disease-induced translational changes and to treat cardiac hypertrophy and heart failure.

[Current status and reflection on minimal access breast surgery]

Minimal access breast surgery with the assistance of an endoscopy or robot has been an important advancement in surgical treatment in recent years. Compared to conventional open surgery, minimal access breast surgery only requires small incisions in concealed areas such as axillary fossa, avoiding visible scars on the surface of the breast, significantly improving the postoperative aesthetic appearance and patient satisfaction. With the rapid development of minimal access breast surgery, several institutions have established their own distinctive techniques. The concept of membrane anatomy in the breast, for example, has led to more natural-looking breast reconstruction following endoscopic procedures. The adoption of the reverse space dissection technique has greatly optimized the workflow of endoscopic breast cancer resection. Intraoperative navigation system for endoscopic breast-conserving surgery could allow precise localization of excision margins. Furthermore, the widespread use of the cold dissection technique for flap separation has reduced surgical duration and minimized flap damage. The emergence of unique techniques in the field of minimal access breast surgery promises to further advance and promote the adoption of minimal access breast surgery in China.

[A retrospective cohort study of the postoperative prothesis-related complications of single-port endoscopic assisted versus open surgery on nipple sparing mastectomy and immediate prosthesis breast reconstruction]

Objective: To examine the postoperative prosthesis-related complications, short-term surgical outcomes and patient satisfaction with breast reconstruction between patients who underwent endoscopic assisted versus conventional nipple sparing mastectomy and immediate prothesis breast reconstruction. Methods: This study was a retrospective cohort study. A retrospective analysis was performed on clinical data of 104 women with breast cancer who received nipple sparing mastectomy and immediate prothesis breast reconstruction from August 2021 to August 2022 at the Breast Tumor Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University. They were divided into two groups according to the surgical approach. A total of 53 patients, aged (43.3±9.9) years (range: 25 to 66 years), underwent endoscopic nipple sparing mastectomy (E-NSM group) and immediate prothesis breast reconstruction. The other 51 patients aged (39.9±7.8) years (range: 25 to 54 years) underwent conventional open surgery (C-NSM group). Short-term surgical outcomes including operation time, postoperative hospital stay, postoperative blood loss, and postoperative drainage volume in 2 days were recorded. Patient satisfaction with breast reconstruction was compared using the Wilcoxon rank sum test. Postoperative prothesis-related complications were investigated to determine the experience to deal with them. Results: No postoperative prosthesis-related infection, prosthesis loss, or necrosis of the nipple-areola complex occurred in the E-NSM group, while 1 patient suffered from hematoma, whose wound was skinned with resuture after disinfection. Five patients in the C-NSM group had prosthesis-related infection, 2 of them received prosthesis removal surgery combined with sufficient antimicrobial agent, another one underwent surgery for subcutaneous placement of the drain, as well as antimicrobial agent therapy, and the rest of them healed up only with antimicrobial agent therapy. All recovered well after treatment. One patient recovered from necrosis of the nipple-areola complex through periodic iodophor disinfection and dressing which ended in improvement of necrotic areas, another patient who had hematoma accepted the same treatment mentioned above and also healed. All the patients mentioned above are now in stable conditions. Patients in the E-NSM group had higher satisfaction with the cosmetic results of the breast prosthesis implant than those in the C-NSM group (Z=-4.511, P<0.01). Conclusions: Both surgical approaches were proven to be safe and effective with a low rate of postoperative prosthesis-related complications. Patients in the E-NSM group were more satisfied with the cosmetic results of breast reconstruction than those in the C-NSM group.

Reduced Mitochondrial Protein Translation Promotes Cardiomyocyte Proliferation and Heart Regeneration

BACKGROUND

The importance of mitochondria in normal heart function are well recognized and recent studies have implicated changes in mitochondrial metabolism with some forms of heart disease. Previous studies demonstrated that knockdown of the mitochondrial ribosomal protein S5 (MRPS5) by small interfering RNA (siRNA) inhibits mitochondrial translation and thereby causes a mitonuclear protein imbalance. Therefore, we decided to examine the effects of MRPS5 loss and the role of these processes on cardiomyocyte proliferation.

METHODS

We deleted a single allele of MRPS5 in mice and used left anterior descending coronary artery ligation surgery to induce myocardial damage in these animals. We examined cardiomyocyte proliferation and cardiac regeneration both in vivo and in vitro. Doxycycline treatment was used to inhibit protein translation. Heart function in mice was assessed by echocardiography. Quantitative real-time polymerase chain reaction and RNA sequencing were used to assess changes in transcription and chromatin immunoprecipitation (ChIP) and BioChIP were used to assess chromatin effects. Protein levels were assessed by Western blotting and cell proliferation or death by histology and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assays. Adeno-associated virus was used to overexpress genes. The luciferase reporter assay was used to assess promoter activity. Mitochondrial oxygen consumption rate, ATP levels, and reactive oxygen species were also analyzed.

RESULTS

We determined that deletion of a single allele of MRPS5 in mice results in elevated cardiomyocyte proliferation and cardiac regeneration; this observation correlates with improved cardiac function after induction of myocardial infarction. We identified ATF4 (activating transcription factor 4) as a key regulator of the mitochondrial stress response in cardiomyocytes from Mrps5+/- mice; furthermore, ATF4 regulates Knl1 (kinetochore scaffold 1) leading to an increase in cytokinesis during cardiomyocyte proliferation. The increased cardiomyocyte proliferation observed in Mrps5+/- mice was attenuated when one allele of Atf4 was deleted genetically (Mrps5+/-/Atf4+/-), resulting in the loss in the capacity for cardiac regeneration. Either MRPS5 inhibition (or as we also demonstrate, doxycycline treatment) activate a conserved regulatory mechanism that increases the proliferation of human induced pluripotent stem cell-derived cardiomyocytes.

CONCLUSIONS

These data highlight a critical role for MRPS5/ATF4 in cardiomyocytes and an exciting new avenue of study for therapies to treat myocardial injury.

mt-Ty 5'tiRNA regulates skeletal muscle cell proliferation and differentiation

In this study, we sought to determine the role of tRNA-derived fragments in the regulation of gene expression during skeletal muscle cell proliferation and differentiation. We employed cell culture to examine the function of mt-Ty 5' tiRNAs. Northern blotting, RT-PCR as well as RNA-Seq, were performed to determine the effects of mt-Ty 5' tiRNA loss and gain on gene expression. Standard and transmission electron microscopy (TEM) were used to characterize cell and sub-cellular structures. mt-Ty 5'tiRNAs were found to be enriched in mouse skeletal muscle, showing increased levels in later developmental stages. Gapmer-mediated inhibition of tiRNAs in skeletal muscle C2C12 myoblasts resulted in decreased cell proliferation and myogenic differentiation; consistent with this observation, RNA-Seq, transcriptome analyses, and RT-PCR revealed that skeletal muscle cell differentiation and cell proliferation pathways were also downregulated. Conversely, overexpression of mt-Ty 5'tiRNAs in C2C12 cells led to a reversal of these transcriptional trends. These data reveal that mt-Ty 5'tiRNAs are enriched in skeletal muscle and play an important role in myoblast proliferation and differentiation. Our study also highlights the potential for the development of tiRNAs as novel therapeutic targets for muscle-related diseases.

PCBP1 regulates alternative splicing of AARS2 in congenital cardiomyopathy

Alanyl-transfer RNA synthetase 2 (AARS2) is a nuclear encoded mitochondrial tRNA synthetase that is responsible for charging of tRNA-Ala with alanine during mitochondrial translation. Homozygous or compound heterozygous mutations in the Aars2 gene, including those affecting its splicing, are linked to infantile cardiomyopathy in humans. However, how Aars2 regulates heart development, and the underlying molecular mechanism of heart disease remains unknown. Here, we found that poly(rC) binding protein 1 (PCBP1) interacts with the Aars2 transcript to mediate its alternative splicing and is critical for the expression and function of Aars2. Cardiomyocyte-specific deletion of Pcbp1 in mice resulted in defects in heart development that are reminiscent of human congenital cardiac defects, including noncompaction cardiomyopathy and a disruption of the cardiomyocyte maturation trajectory. Loss of Pcbp1 led to an aberrant alternative splicing and a premature termination of Aars2 in cardiomyocytes. Additionally, Aars2 mutant mice with exon-16 skipping recapitulated heart developmental defects observed in Pcbp1 mutant mice. Mechanistically, we found dysregulated gene and protein expression of the oxidative phosphorylation pathway in both Pcbp1 and Aars2 mutant hearts; these date provide further evidence that the infantile hypertrophic cardiomyopathy associated with the disorder oxidative phosphorylation defect type 8 (COXPD8) is mediated by Aars2. Our study therefore identifies Pcbp1 and Aars2 as critical regulators of heart development and provides important molecular insights into the role of disruptions in metabolism on congenital heart defects.

INKILN is a Novel Long Noncoding RNA Promoting Vascular Smooth Muscle Inflammation via Scaffolding MKL1 and USP10

BACKGROUND

Activation of vascular smooth muscle cell (VSMC) inflammation is vital to initiate vascular disease. The role of human-specific long noncoding RNAs in VSMC inflammation is poorly understood.

METHODS

Bulk RNA sequencing in differentiated human VSMCs revealed a novel human-specific long noncoding RNA called inflammatory MKL1 (megakaryoblastic leukemia 1) interacting long noncoding RNA (INKILN). INKILN expression was assessed in multiple in vitro and ex vivo models of VSMC phenotypic modulation as well as human atherosclerosis and abdominal aortic aneurysm. The transcriptional regulation of INKILN was verified through luciferase reporter and chromatin immunoprecipitation assays. Loss-of-function and gain-of-function studies and multiple RNA-protein and protein-protein interaction assays were used to uncover a mechanistic role of INKILN in the VSMC proinflammatory gene program. Bacterial artificial chromosome transgenic mice were used to study INKILN expression and function in ligation injury-induced neointimal formation.

RESULTS

INKILN expression is downregulated in contractile VSMCs and induced in human atherosclerosis and abdominal aortic aneurysm. INKILN is transcriptionally activated by the p65 pathway, partially through a predicted NF-κB (nuclear factor kappa B) site within its proximal promoter. INKILN activates proinflammatory gene expression in cultured human VSMCs and ex vivo cultured vessels. INKILN physically interacts with and stabilizes MKL1, a key activator of VSMC inflammation through the p65/NF-κB pathway. INKILN depletion blocks interleukin-1β-induced nuclear localization of both p65 and MKL1. Knockdown of INKILN abolishes the physical interaction between p65 and MKL1 and the luciferase activity of an NF-κB reporter. Furthermore, INKILN knockdown enhances MKL1 ubiquitination through reduced physical interaction with the deubiquitinating enzyme USP10 (ubiquitin-specific peptidase 10). INKILN is induced in injured carotid arteries and exacerbates ligation injury-induced neointimal formation in bacterial artificial chromosome transgenic mice.

CONCLUSIONS

These findings elucidate an important pathway of VSMC inflammation involving an INKILN/MKL1/USP10 regulatory axis. Human bacterial artificial chromosome transgenic mice offer a novel and physiologically relevant approach for investigating human-specific long noncoding RNAs under vascular disease conditions.

A defect in mitochondrial protein translation influences mitonuclear communication in the heart

The regulation of the informational flow from the mitochondria to the nucleus (mitonuclear communication) is not fully characterized in the heart. We have determined that mitochondrial ribosomal protein S5 (MRPS5/uS5m) can regulate cardiac function and key pathways to coordinate this process during cardiac stress. We demonstrate that loss of Mrps5 in the developing heart leads to cardiac defects and embryonic lethality while postnatal loss induces cardiac hypertrophy and heart failure. The structure and function of mitochondria is disrupted in Mrps5 mutant cardiomyocytes, impairing mitochondrial protein translation and OXPHOS. We identify Klf15 as a Mrps5 downstream target and demonstrate that exogenous Klf15 is able to rescue the overt defects and re-balance the cardiac metabolome. We further show that Mrps5 represses Klf15 expression through c-myc, together with the metabolite L-phenylalanine. This critical role for Mrps5 in cardiac metabolism and mitonuclear communication highlights its potential as a target for heart failure therapies.

Sox17 mediates adult arterial endothelial cell adaptation to hemodynamics

Sox17 is a critical regulator of arterial identity during early embryonic vascular development. However, its role in adult endothelial cells (ECs) are not fully understood. Sox17 is highly expressed in arterial ECs but not in venous ECs throughout embryonic development to adulthood suggesting that it may play a functional role in adult arteries. Here, we investigated Sox17 mediated phenotypical changes in adult ECs. To precisely control the temporal expression level of Sox17, we designed a tetracycline-inducible lentiviral gene expression system to express Sox17 selectively in cultured venous ECs. We confirmed that Sox17-induced ECs exhibit a gene profile favoring arterial and tip cell identity. Furthermore, in comparison to control ECs, Sox17-activated ECs under shear leads to greater expression of arterial markers and suppression of venous identity. These data suggest that Sox17 enables greater hemodynamic adaptability of ECs in response to fluid shear stress. Here, we also demonstrate key morphogenic behaviors of Sox17-mediated ECs. In both vasculogenic and angiogenic 3D fibrin gel studies, Sox17-mediated ECs prefer to form cohesive vessels with one another while interfering the vessel formation of the control ECs. Sox17-mediated ECs elicit hyper-sprouting behavior in the presence of pericytes but not fibroblasts, suggesting Sox17 mediated sprouting frequency is dependent on supporting cell type. Using a microfluidic chip, we also show that Sox17-mediated ECs maintain thinner diameter vessels that do not widen under interstitial flow like the control ECs. Taken together, these data showed that Sox17 mediated EC gene expression and phenotypical changes are highly modulated in the context of biomechanical stimuli, suggesting Sox17 plays a role in regulating the arterial ECs adaptability under arterial hemodynamics as well as tip cells behavior during angiogenesis and vasculogenesis. The results from this study may be valuable in improving vein graft adaptation to arterial hemodynamics and bioengineering microvasculature for tissue engineering applications.

INKILN is a novel long noncoding RNA promoting vascular smooth muscle inflammation via scaffolding MKL1 and USP10

Background

Activation of vascular smooth muscle cells (VSMCs) inflammation is vital to initiate vascular disease. However, the role of human-specific long noncoding RNAs (lncRNAs) in VSMC inflammation is poorly understood.

Methods

Bulk RNA-seq in differentiated human VSMCs revealed a novel human-specific lncRNA called IN flammatory M K L1 I nteracting L ong N oncoding RNA ( INKILN ). INKILN expression was assessed in multiple in vitro and ex vivo models of VSMC phenotypic modulation and human atherosclerosis and abdominal aortic aneurysm (AAA) samples. The transcriptional regulation of INKILN was determined through luciferase reporter system and chromatin immunoprecipitation assay. Both loss- and gain-of-function approaches and multiple RNA-protein and protein-protein interaction assays were utilized to uncover the role of INKILN in VSMC proinflammatory gene program and underlying mechanisms. Bacterial Artificial Chromosome (BAC) transgenic (Tg) mice were utilized to study INKLIN expression and function in ligation injury-induced neointimal formation.

Results

INKILN expression is downregulated in contractile VSMCs and induced by human atherosclerosis and abdominal aortic aneurysm. INKILN is transcriptionally activated by the p65 pathway, partially through a predicted NF-κB site within its proximal promoter. INKILN activates the proinflammatory gene expression in cultured human VSMCs and ex vivo cultured vessels. Mechanistically, INKILN physically interacts with and stabilizes MKL1, a key activator of VSMC inflammation through the p65/NF-κB pathway. INKILN depletion blocks ILIβ-induced nuclear localization of both p65 and MKL1. Knockdown of INKILN abolishes the physical interaction between p65 and MKL1, and the luciferase activity of an NF-κB reporter. Further, INKILN knockdown enhances MKL1 ubiquitination, likely through the reduced physical interaction with the deubiquitinating enzyme, USP10. INKILN is induced in injured carotid arteries and exacerbates ligation injury-induced neointimal formation in BAC Tg mice.

Conclusions

These findings elucidate an important pathway of VSMC inflammation involving an INKILN /MKL1/USP10 regulatory axis. Human BAC Tg mice offer a novel and physiologically relevant approach for investigating human-specific lncRNAs under vascular disease conditions.

Epsin Nanotherapy Regulates Cholesterol Transport to Fortify Atheroma Regression

BACKGROUND

Excess cholesterol accumulation in lesional macrophages elicits complex responses in atherosclerosis. Epsins, a family of endocytic adaptors, fuel the progression of atherosclerosis; however, the underlying mechanism and therapeutic potential of targeting Epsins remains unknown. In this study, we determined the role of Epsins in macrophage-mediated metabolic regulation. We then developed an innovative method to therapeutically target macrophage Epsins with specially designed S2P-conjugated lipid nanoparticles, which encapsulate small-interfering RNAs to suppress Epsins.

METHODS

We used single-cell RNA sequencing with our newly developed algorithm MEBOCOST (Metabolite-mediated Cell Communication Modeling by Single Cell Transcriptome) to study cell-cell communications mediated by metabolites from sender cells and sensor proteins on receiver cells. Biomedical, cellular, and molecular approaches were utilized to investigate the role of macrophage Epsins in regulating lipid metabolism and transport. We performed this study using myeloid-specific Epsin double knockout (LysM-DKO) mice and mice with a genetic reduction of ABCG1 (ATP-binding cassette subfamily G member 1; LysM-DKO-ABCG1fl/+). The nanoparticles targeting lesional macrophages were developed to encapsulate interfering RNAs to treat atherosclerosis.

RESULTS

We revealed that Epsins regulate lipid metabolism and transport in atherosclerotic macrophages. Inhibiting Epsins by nanotherapy halts inflammation and accelerates atheroma resolution. Harnessing lesional macrophage-specific nanoparticle delivery of Epsin small-interfering RNAs, we showed that silencing of macrophage Epsins diminished atherosclerotic plaque size and promoted plaque regression. Mechanistically, we demonstrated that Epsins bound to CD36 to facilitate lipid uptake by enhancing CD36 endocytosis and recycling. Conversely, Epsins promoted ABCG1 degradation via lysosomes and hampered ABCG1-mediated cholesterol efflux and reverse cholesterol transport. In a LysM-DKO-ABCG1fl/+ mouse model, enhanced cholesterol efflux and reverse transport due to Epsin deficiency was suppressed by the reduction of ABCG1.

CONCLUSIONS

Our findings suggest that targeting Epsins in lesional macrophages may offer therapeutic benefits for advanced atherosclerosis by reducing CD36-mediated lipid uptake and increasing ABCG1-mediated cholesterol efflux.

[Effects of vaccines on the viral negative conversion of children with COVID-19]

Objective: To explore the effect of vaccination on viral negative conversion of children with COVID-19. Methods: A retrospective cohort study was conducted. A cohort of 189 children aged 3-14 years with COVID-19 admitted to Renji Hospital (South branch) of Shanghai Jiao Tong University School of Medicine from April 7^th to May 19^th 2022 was enrolled in the study. According to the vaccination status, the infected children were divided into an unvaccinated group and a vaccinated group. Age, gender, severity, clinical manifestations, and laboratory tests, etc. were compared between groups, by rank sum test or chi-square test. The effects of vaccination on viral negative conversion were analyzed by a Cox mixed-effects regression model. Additionally, a questionnaire survey was conducted among the parents of unvaccinated children to analyze the reasons for not being vaccinated. Results: A total of 189 children aged 3-14 years were enrolled, including 95 males (50.3%) and 94 females (49.7%), aged 5.7 (4.1,8.6) years. There were 117 cases (61.9%) in the unvaccinated group and 72 cases (38.1%) in the vaccinated group. The age of the vaccinated group was higher than that of the unvaccinated group (8.8 (6.8, 10.6) vs. 4.5 (3.6, 5.9) years, Z=9.45, P<0.001). No significant differences were found in clinical manifestations, disease severity, and laboratory results between groups (all P>0.05), except for the occurrence rate of cough symptoms, which was significantly higher in the vaccinated group than in the non-vaccinated group (68.1% (49/72) vs. 50.4% (59/117),χ²=5.67, P=0.017). The Kaplan-Meier survival curve and Cox mixed-effects regression model showed that the time to the viral negative conversion was significantly shorter in the vaccinated group compared with the unvaccinated group (8 (7, 10) vs. 11 (9, 12) d, Z=5.20, P<0.001; adjusted HR=2.19 (95%CI 1.62-2.97)). For questionnaire survey on the reasons for not receiving a vaccination, 115 questionnaires were distributed and 112 valid questionnaires (97.4%) were collected. The main reasons for not being vaccinated were that parents thought that their children were not in the range of appropriate age for vaccination (51 cases, 45.5%) and children were in special physical conditions (47 cases, 42.0%). Conclusion: Vaccination can effectively shorten the negative conversion time of children with COVID-19 and targeted programs should be developed to increase eligible children's vaccination rate for SARS-CoV-2 vaccination.

[Recommendations for the diagnosis and treatment of connective tissue disease-associated interstitial lung disease in China]

Interstitial lung disease (ILD) is a frequent complication of patients with connective tissue disease (CTD) and significantly affects morbidity and mortality. Disease course may vary from stable or mildly progressive to more severe, with rapid loss of lung function. At present, there are great challenges and poor prognosis in the diagnosis and treatment of CTD-ILD. Based on the evidence and guidelines from China and other countries, experts from the Chinese Rheumatology Association developed standardization of diagnosis and treatment of CTD-ILD. The aim is to strengthen the early identification of, standardize the diagnosis and treatment of CTD-ILD, and delay the progress of the disease.

Abstract P314: Loss Of Set7 Prevents Isoproterenol-induced Heart Dysfunction

Recent studies have revealed the influence of histone-modifying enzymes in cardiac remodeling and dysfunction. The Set7 methyltransferase regulates the expression of several genes through methylation of histones and modulates the activity of non-histone proteins. However, the role of Set7 in heart dysfunction remains unknown. To answer this question, wild type (WT) and Set7 knockout (KO) male mice were injected with isoproterenol (iso) or saline (s) subcutaneously for 14 days. The WTiso mice displayed decreased Set7 activity in the heart compared to WTs mice (Table 1). Both WTiso and KOiso mice exhibited increased heart weight to tibia length ratio (HW/TL) and cardiomyocyte area. However, KOiso mice had higher HW/TL and cardiomyocyte area compared to WTiso mice. Sirius Red staining revealed that both WT and KO mice injected with iso had increased myocardial fibrosis compared to their controls. Nonetheless, loss of Set7 attenuated iso-induced myocardial fibrosis. Echocardiogram showed that WTiso mice had lower ejection fraction (EF) and fractional shortening (FS), and higher E/A ratio compared to WTs mice. Conversely, KOiso mice did not show alteration on these parameters compared to their controls. RNA sequencing analysis revealed that biological processes related to oxidant detoxication, cellular respiration, and anti-inflammatory response were enriched in the heart of KOiso mice compared to WTiso mice. On the other hand, biological processes related to cell aging, interferon production, and immune response were downregulated in the heart of KOiso mice compared to WTiso mice. Collectively, our data suggest that Set7 deletion prevents iso-induced heart dysfunction.

Abstract P2059: Poly(rC)-binding Protein-1 (Pcbp1) Is Essential For Heart Development

Rationale: Proper development of the heart relies on a tightly regulated, yet diverse, pattern of gene expression that is governed by transcriptional, post-transcriptional, and translational processes. Congenital heart disease (CHD) is the most common birth defect and a leading cause of morbidity and mortality in children. While the genetic cause of some types of CHD has been identified, the molecular basis for the rest remains elusive. Poly(rC)-binding protein 1 (Pcbp1) is a RNA-binding protein that regulates RNA processing as well as post-transcriptional and translational processes in a variety of biological systems.

Hypothesis: Pcbp1 play a critical role in regulating heart development by governing Notch and UPR pathways and mediating proper Aars2 gene splicing.

Methods and Results: Germline deletion of Pcbp1 results in lethality before embryonic day (E) 8.5. We generated a cardiac-specific deletion of Pcbp1 by crossing Pcbp1-Flox with cTNT-Cre mice (Pcbp1-cKO cTNT ) and found that Pcbp1-cKO cTNT mice is 50% lethal perinatally. Embryonic hearts of Pcbp1-cKO cTNT mice displayed ventricular non-compaction and abnormal ventricular apex formation. Deep RNA sequencing of Pcbp1-cKO cTNT hearts revealed alteration of gene expression profiles reflective on ventricular maturation delay and dysregulation of Notch and UPR pathways. Interestingly, loss of Pcbp1 in cardiomyocytes disrupts alternative splicing of many important genes including Aars2, a gene associated with congenital mitochondrial cardiomyopathy. Pcbp1 deficiency resulted in creation of an Aars2 exon16-skipping variant, leading to its premature termination. eCLIP-seq showed that Pcbp1 primarily binds to CU-rich motifs at 3’UTR, distal intron and CDS regions of targets, and it interacts with regions of Aars2 transcript near exon 16. Using CRISPR/Cas9 technology, we knocked in loxP sites flanking the exon 16 of Aars2 (Aars2-Flox), and cross the floxed mice with cTNT-Cre mice to generate cardiac-specific exon16 deletion mutant of Aars2 (Aars2-cKO cTNT ). Intriguingly, abnormality in Aars2-cKO cTNT embryonic heart phenocopy aspects of ventricular non-compaction and malformation observed in Pcbp1-cKO cTNT heart. Accordingly, the transcriptome from hearts of Pcbp1-cKO cTNT and Aars2-cKO cTNT display high concordance and similarity and share strikingly common dysregulated pathways.

Conclusions: We discover a novel function of Pcbp1 in heart development by regulating Notch and UPR pathways. Additionally, Pcbp1 is indispensable for Aars2 gene splicing, whose deficiency is associated with congenital cardiomyopathy. Our findings suggest modulating Pcbp1 in developing hearts may offer a novel therapeutic intervention for congenital heart failure.

Set7 Deletion Prevents Glucose Intolerance and Improves the Recovery of Cardiac Function After Ischemia and Reperfusion in Obese Female Mice

BACKGROUND/AIMS

An obesogenic diet (high fat and sugar, low fiber) is associated with an increased risk for metabolic and cardiovascular disorders. Previous studies have demonstrated that epigenetic changes can modify gene transcription and protein function, playing a key role in the development of several diseases. The methyltransferase Set7 methylates histone and non-histone proteins, influencing diverse biological and pathological processes. However, the functional role of Set7 in obesity-associated metabolic and cardiovascular complications is unknown.

METHODS

Wild type and Set7 knockout female mice were fed a normal diet or an obesogenic diet for 12 weeks. Body weight gain and glucose tolerance were measured. The 3T3-L1 cells were used to determine the role of Set7 in white adipogenic differentiation. Cardiac morphology and function were evaluated by histology and echocardiography. An ex vivo Langendorff perfusion system was used to model cardiac ischemia/reperfusion (I/R).

RESULTS

Here, we report that Set7 protein levels were enhanced in the heart and perigonadal adipose tissue (PAT) of female mice fed an obesogenic diet. Significantly, loss of Set7 prevented obesogenic diet-induced glucose intolerance in female mice although it did not affect the obesogenic diet-induced increase in body weight gain and adiposity in these animals, nor did Set7 inhibition change white adipogenic differentiation in vitro. In addition, loss of Set7 prevented the compromised cardiac functional recovery following ischemia and reperfusion (I/R) injury in obesogenic diet-fed female mice; however, deletion of Set7 did not influence obesogenic diet-induced cardiac hypertrophy nor the hemodynamic and echocardiographic parameters.

CONCLUSION

These data indicate that Set7 plays a key role in obesogenic diet-induced glucose intolerance and compromised myocardial functional recovery after I/R in obese female mice.

The Role of Endothelial-to-Mesenchymal Transition in Cardiovascular Disease

Endothelial-to-mesenchymal transition (EndoMT) is the process of endothelial cells progressively losing endothelial-specific markers and gaining mesenchymal phenotypes. In the normal physiological condition, EndoMT plays a fundamental role in forming the cardiac valves of the developing heart. However, EndoMT contributes to the development of various cardiovascular diseases (CVD), such as atherosclerosis, valve diseases, fibrosis, and pulmonary arterial hypertension (PAH). Therefore, a deeper understanding of the cellular and molecular mechanisms underlying EndoMT in CVD should provide urgently needed insights into reversing this condition. This review summarizes a 30-year span of relevant literature, delineating the EndoMT process in particular, key signaling pathways, and the underlying regulatory networks involved in CVD.

Abstract 196: Poly (rC)-binding Protein-1 (Pcbp1) Is Essential For Vascular Development

The formation of the heart and the connecting vessels is essential for the function of the vertebrates, as vascular deficiency during embryonic development often leads to embryonic lethality. The vasculature forms as a branching network of endothelial cells (ECs) that becomes specified and assembles into vessels. the formation of new blood vessels from the existing vasculatures, or angiogenesis, is fundamental during development and pathological processes. Critical factors in governing vascular development are often required for organismal survival. Hence, gaining a complete understanding of the developmental process requires unique approaches to study tissue or cell-type specific functions. Poly(rC)-Binding Protein 1 (Pcbp1) is an evolutionarily conserved RNA binding protein that is not well understood in vivo . Pcbp1 is abundantly expressed in the angiogenic endothelium. However, little is known about the function and mechanism of Pcbp1 in the context of angiogenesis and vascular development. Germline deletion of Pcbp1 results in peri-implantation lethality, which limits its potential for studying the role of Pcbp1 in development. To address this deficit, we had generated an inducible endothelial deletion of Pcbp1 with Cdh5-Cre ERT2 (Pcbp1-ieKO) to study its role in vascular development. When the EC deletion was induced at embryonic day (E) 9.5, Pcbp1-ieKO exhibited inadequate angiogenesis in the hindbrain at E12.5. Furthermore, when the EC deletion was induced at postnatal day (P) 1, Pcbp1-ieKO displayed reduced coronary and brain vascular density, as well as blunted retinal angiogenesis at P6. Single-cell RNA sequencing of Pcbp1-ieKO retina at P6 revealed a significant reduction in EC population and expression of genes critical for angiogenesis downstream of VEGF signaling and NOTCH activation. Notably, knockdown of Pcbp1 in human colony-forming endothelial cells (hCFEC) blunts the VEGFR2 and NOTCH activation upon VEGFA treatment. Our preliminary results suggest Pcbp1 is a critical regulator for angiogenesis, future studies will be directed at identifying the mechanism of Pcbp1 in regulating VEGF and NOTCH signaling, ultimately to provide insights for novel therapeutic strategies to control angiogenesis in cardiovascular disease.

Diabetes and Its Cardiovascular Complications: Comprehensive Network and Systematic Analyses

Diabetes mellitus is a worldwide health problem that usually comes with severe complications. There is no cure for diabetes yet and the threat of these complications is what keeps researchers investigating mechanisms and treatments for diabetes mellitus. Due to advancements in genomics, epigenomics, proteomics, and single-cell multiomics research, considerable progress has been made toward understanding the mechanisms of diabetes mellitus. In addition, investigation of the association between diabetes and other physiological systems revealed potentially novel pathways and targets involved in the initiation and progress of diabetes. This review focuses on current advancements in studying the mechanisms of diabetes by using genomic, epigenomic, proteomic, and single-cell multiomic analysis methods. It will also focus on recent findings pertaining to the relationship between diabetes and other biological processes, and new findings on the contribution of diabetes to several pathological conditions.

Deletion of miRNA-22 Induces Cardiac Hypertrophy in Females but Attenuates Obesogenic Diet-Mediated Metabolic Disorders

BACKGROUND/AIMS

Obesity is a risk factor associated with cardiometabolic complications. Recently, we reported that miRNA-22 deletion attenuated high-fat diet-induced adiposity and prevented dyslipidemia without affecting cardiac hypertrophy in male mice. In this study, we examined the impact of miRNA-22 in obesogenic diet-induced cardiovascular and metabolic disorders in females.

METHODS

Wild type (WT) and miRNA-22 knockout (miRNA-22 KO) females were fed a control or an obesogenic diet. Body weight gain, adiposity, glucose tolerance, insulin tolerance, and plasma levels of total cholesterol and triglycerides were measured. Cardiac and white adipose tissue remodeling was assessed by histological analyses. Echocardiography was used to evaluate cardiac function and morphology. RNA-sequencing analysis was employed to characterize mRNA expression profiles in female hearts.

RESULTS

Loss of miRNA-22 attenuated body weight gain, adiposity, and prevented obesogenic diet-induced insulin resistance and dyslipidemia in females. WT obese females developed cardiac hypertrophy. Interestingly, miRNA-22 KO females displayed cardiac hypertrophy without left ventricular dysfunction and myocardial fibrosis. Both miRNA-22 deletion and obesogenic diet changed mRNA expression profiles in female hearts. Enrichment analysis revealed that genes associated with regulation of the force of heart contraction, protein folding and fatty acid oxidation were enriched in hearts of WT obese females. In addition, genes related to thyroid hormone responses, heart growth and PI3K signaling were enriched in hearts of miRNA-22 KO females. Interestingly, miRNA-22 KO obese females exhibited reduced mRNA levels of Yap1, Egfr and Tgfbr1 compared to their respective controls.

CONCLUSION

This study reveals that miRNA-22 deletion induces cardiac hypertrophy in females without affecting myocardial function. In addition, our findings suggest miRNA-22 as a potential therapeutic target to treat obesity-related metabolic disorders in females.

MEF2 (Myocyte Enhancer Factor 2) Is Essential for Endothelial Homeostasis and the Atheroprotective Gene Expression Program

OBJECTIVE

Atherosclerosis predominantly forms in regions of oscillatory shear stress while regions of laminar shear stress are protected. This protection is partly through the endothelium in laminar flow regions expressing an anti-inflammatory and antithrombotic gene expression program. Several molecular pathways transmitting these distinct flow patterns to the endothelium have been defined. Our objective is to define the role of the MEF2 (myocyte enhancer factor 2) family of transcription factors in promoting an atheroprotective endothelium. Approach and Results: Here, we show through endothelial-specific deletion of the 3 MEF2 factors in the endothelium, Mef2a, -c, and -d, that MEF2 is a critical regulator of vascular homeostasis. MEF2 deficiency results in systemic inflammation, hemorrhage, thrombocytopenia, leukocytosis, and rapid lethality. Transcriptome analysis reveals that MEF2 is required for normal regulation of 3 pathways implicated in determining the flow responsiveness of the endothelium. Specifically, MEF2 is required for expression of Klf2 and Klf4, 2 partially redundant factors essential for promoting an anti-inflammatory and antithrombotic endothelium. This critical requirement results in phenotypic similarities between endothelial-specific deletions of Mef2a/c/d and Klf2/4. In addition, MEF2 regulates the expression of Notch family genes, Notch1, Dll1, and Jag1, which also promote an atheroprotective endothelium. In contrast to these atheroprotective pathways, MEF2 deficiency upregulates an atherosclerosis promoting pathway through increasing the amount of TAZ (transcriptional coactivator with PDZ-binding motif).

CONCLUSIONS

Our results implicate MEF2 as a critical upstream regulator of several transcription factors responsible for gene expression programs that affect development of atherosclerosis and promote an anti-inflammatory and antithrombotic endothelium. Graphic Abstract: A graphic abstract is available for this article.

Intercalated disc protein Xinβ is required for Hippo-YAP signaling in the heart

Intercalated discs (ICD), specific cell-to-cell contacts that connect adjacent cardiomyocytes, ensure mechanical and electrochemical coupling during contraction of the heart. Mutations in genes encoding ICD components are linked to cardiovascular diseases. Here, we show that loss of Xinβ, a newly-identified component of ICDs, results in cardiomyocyte proliferation defects and cardiomyopathy. We uncovered a role for Xinβ in signaling via the Hippo-YAP pathway by recruiting NF2 to the ICD to modulate cardiac function. In Xinβ mutant hearts levels of phosphorylated NF2 are substantially reduced, suggesting an impairment of Hippo-YAP signaling. Cardiac-specific overexpression of YAP rescues cardiac defects in Xinβ knock-out mice—indicating a functional and genetic interaction between Xinβ and YAP. Our study reveals a molecular mechanism by which cardiac-expressed intercalated disc protein Xinβ modulates Hippo-YAP signaling to control heart development and cardiac function in a tissue specific manner. Consequently, this pathway may represent a therapeutic target for the treatment of cardiovascular diseases.

Intercalated discs ensure mechanical and electrochemical coupling during contraction of the heart. Here, the authors show that loss of Xinβ results in cardiomyocyte proliferation defects and cardiomyopathy by influencing the Hippo-YAP signalling pathway, thus affecting cardiac development and function.

P1585Increased circulating galectin 1 level is associated with progression of kidney function decline in patients with suspected coronary artery disease, independent of diabetes

Background

Galectin-1 modulates acute and chronic inflammation, and is associated with glucose homeostasis and chronic renal disease. Whether serum Galectin-1 levels could predict the short-term and long-term renal outcomes after contrast exposure in patients with suspected coronary artery disease remains uncertain.

Purpose

This study aimed to evaluate the relationship between serum Galectin-1 levels and the incidence of contrast-induced nephropathy and to investigate the predictive role of circulating galectin-1 levels in renal function decline in patients undergoing coronary angiography.

Methods

In total, 798 patients who had received coronary angiography were enrolled. Serum galectin-1 levels were determined before administration of contrast media. Contrast-induced nephropathy was defined as a rise in serum creatinine of 0.5 mg/dL or a 25% increase from baseline within 48 h after the procedure. Progressive renal function decline was defined as >30% decrease in estimated glomerular filtration rate after discharge. All patients were followed up for at least one year or until the occurrence of death after coronary angiography.

Results

Overall, contrast-induced nephropathy occurred in 41 (5.1%) patients. During a median follow-up of 1.4±1.1 years, 80 (10.0%) cases had subsequent decline in renal function. After adjustment for demographic characteristics, kidney function, traditional risk factors, and medications, higher galectin-1 level was found to be independently associated with a higher risk for mortality and renal function decline (tertile 2, HR=3.12 95% CI,1.25–7.78; tertile 3, HR=3.25, 95% CI,1.42–7.41) but not for contrast-induced nephropathy, regardless of the presence of diabetes.

Conclusions

Higher baseline serum galectin-1 levels were associated with a higher risk of mortality and renal function decline in patients undergoing coronary angiography. Galectin-1 may play a pivotal role in progressive renal dysfunction, but further studies are needed to verify these results.

Acknowledgement/Funding

Ministry of Science and Technology of Taiwan (MOST 104-2314-B-075-047), Taipei Veterans General Hospital (V105C-0207, V106C-045, V108C-195)

Abstract 919: Intercalated Disk Protein Xin-beta is Required for the Hippo/YAP Signaling in the Heart

Cardiovascular diseases continue to be a leading cause of death and disability. Despite this alarming fact, there is lack of effectual treatment and the molecular mechanisms underlying these devastating diseases remain elusive. Intercalated disk (ICD) is not only essential for the integrity of cardiomyocytes to withstand the strong mechanical forces imposed by constant heart beating; it is also critical for the dissemination of the electrical signal that initiates cardiac contraction. However, relatively less is known about how ICD transmits pathophysiological signals in cardiomyocytes to modulate gene expression and cardiac function. The Xin-α and Xin-β, belongs to a family of Xin-repeat containing proteins, are primarily located at the ICD of adult cardiomyocytes. They play an important role during heart development. Interestingly, the human homologue of the mouse Xin-β gene was mapped to a locus associated with cardiomyopathy; most importantly, mutations in Xin-α and Xin-β have been found in patients with cardiomyopathy, underscoring the importance of Xin genes to cardiac disease. Our previous studies have shown that Xin-β KO mice die postnatally with severe cardiomyopathy. Here, we report that loss of Xin-β results in defect in cardiomyocyte proliferation. Unbiased transcriptome analyses reveal that gene program related to the Hippo/Yap pathway is altered, leading to the hypothesis that Xin-β regulates cardiomyocyte proliferation and cardiac function by modulating the Hippo/Yap signaling. We identify physical and genetic interaction between Xin-β and components of the Hippo/Yap pathway. We further show that the expression of Xin-β is transcriptionally regulated by Mef2a, Yap and Tead1, suggesting the presence of a Xin-β/Yap feedback regulatory network in the heart. Strikingly, cardiac-specific overexpression of Yap markedly rescues cardiac defects in Xin-β KO mice; indicating a functional and genetic interaction between Xin-β and Yap. Together, our study reveals a novel molecular mechanism by which the ICD protein Xin-β modulates important pathophysiological Hippo/Yap signals to control heart development and cardiac function. Molecules uncovered here will become candidate targets for therapeutic treatment of cardiac disease.

Abstract 895: The Role of Poly(rC)-Binding Protein-1 in Heart Development

Poly(rC)-Binding Protein-1 (Pcbp1) belongs to the KH homology superfamily of nucleic acid-binding proteins, which has been implicated in a vast array of biological processes such as iron transport, RNA processing, post-transcriptional and translational regulations. Germline deletion of Pcbp1 results in embryonic lethality before embryonic day (E) 8.5. To investigate the role of Pcbp1 in heart development, we generated cardiac-specific conditional deletion of Pcbp1 (Pcbp1-cKO) by crossing the Pcbp1-flox with cTNT-Cre mice. The observed frequencies for Pcbp1-cKO at E12.5 and E16.5 are normal, but no surviving Pcbp1-cKO mice were observed at weaning, suggesting the Pcbp1-cKO is perinatal lethal. E12.5 Pcbp1-cKO hearts are smaller with thin myocardium. At E16.5, Pcbp1 cKO hearts displayed ventricular non-compaction and abnormal ventricular apex formation. To understand molecular mechanisms, we perform RNA sequencing follow by differential gene expression analysis in Pcbp1-cKO hearts at E16.5. We found 241 genes were significantly dysregulated and identified unfolded protein response as a key pathway dysregulated. Furthermore, through alternative splicing analysis, we identified 168 uniquely spliced junctions in 139 genes. Of these, 10 differentially spliced genes are also differentially expressed. Future studies will be performed to better understand the biological function and mechanism of Pcbp1 in the heart. Together, this study suggests Pcbp1 is an important regulator of heart development.

[Clinical features of patients with primary Sjögren's syndrome complicated with venous thrombosis]

Objective: To analyze the clinical characteristics of primary Sjögren's syndrome (pSS) with venous system thrombosis (VT), and to improve the understanding of the disease. Methods: The clinical and laboratory characteristics of 16 cases of pSS with VT were analyzed retrospectively. Results: Among 16 cases, 12 cases was women, 2 case was men, age between 45 and 71.There were 14 cases of lower extremity VT, 2 case of jugular vein thrombosis.Twelve patients admitted with dry symptoms and 4 patients with pulmonary symptoms.Antiphospholipid antibodies were negative.The positive cases of anti-SSA 52 000 and anti-SSA 60 000 were 12 cases respectively.Sixteen cases had interstitial lung diseases. Conclusion: pSS are potential VT high risk, especially in patients with interstitial lung disease and anti-SSA positive.We should improve the VT vigilance of pSS patients.

Transforming growth factor β1 suppresses proinflammatory gene program independent of its regulation on vascular smooth muscle differentiation and autophagy

Transforming growth factor β (TGFβ) signaling plays crucial roles in maintaining vascular integrity and homeostasis, and is established as a strong activator of vascular smooth muscle cell (VSMC) differentiation. Chronic inflammation is a hallmark of various vascular diseases. Although TGFβ signaling has been suggested to be protective against inflammatory aortic aneurysm progression, its exact effects on VSMC inflammatory process and the underlying mechanisms are not fully unraveled. Here we revealed that TGFβ1 suppressed the expression of a broad array of proinflammatory genes while potently induced the expression of contractile genes in cultured primary human coronary artery SMCs (HCASMCs). The regulation of TGFβ1 on VSMC contractile and proinflammatory gene programs appeared to occur in parallel and both processes were through a SMAD4-dependent canonical pathway. We also showed evidence that the suppression of TGFβ1 on VSMC proinflammatory genes was mediated, at least partially through the blockade of signal transducer and activator of transcription 3 (STAT3) and NF-κB pathways. Interestingly, our RNA-seq data also revealed that TGFβ1 suppressed gene expression of a battery of autophagy mediators, which was validated by western blot for the conversion of microtubule-associated protein light chain 3 (LC3) and by immunofluo-rescence staining for LC3 puncta. However, impairment of VSMC autophagy by ATG5 deletion failed to rescue TGFβ1 influence on both VSMC contractile and proinflammatory gene programs, suggesting that TGFβ1-regulated VSMC differentiation and inflammation are not attributed to TGFβ1 suppression on autophagy. In summary, our results demonstrated an important role of TGFβ signaling in suppressing proinflammatory gene program in cultured primary human VSMCs via the blockade on STAT3 and NF-κB pathway, therefore providing novel insights into the mechanisms underlying the protective role of TGFβ signaling in vascular diseases.

Abstract 511: Mef2 Transcription Factors are Essential Regulators of Endothelial Morphology and Functions

Background: Laminar shear stress on the endothelium promotes atheroprotecive gene expression. In vitro experiments support a model of laminar shear stress activating the Mef2 transcription factors that in turn induce transcription of Klf2 and Klf4, which regulate many anti-inflammatory and anti-thrombotic genes. However, this model has not been tested in vivo. Three Mef2 transcription factors (Mef2a, -c, and -d) are expressed in the endothelium. To understand their functions and test this model, we generated mice with inducible, endothelial-specific deletions of Mef2c, Mef2a/c, and Mef2a/c/d.

Methods & Results: We previously reported that endothelial Mef2c inhibits the formation of endothelial actin stress fibers and migration of smooth muscle cells across the internal elastic lamina into the intima. Combined deletion of endothelial Mef2a/c produced a similar phenotype. Neither of these deletions affected survival or altered the levels of Klf2 or Klf4. However, combined deletions of Mef2a/c/d led to death 10-14 days after induction. Pulmonary hemorrhage was consistently observed as was variable amounts in other organs. En face imaging of the aorta and vena cava revealed a substantial increase in endothelial cell density and proliferation. The aortic endothelium displayed extensive actin stress fibers but the overall organization was not substantially changed. However, the vena cava was disorganized with endothelial cell aggregation. Transcriptome analysis showed ≥ 2-fold alterations in expression of 894 genes, with many important for endothelial function. Notably, Klf2 and Klf4 were both decreased in Mef2a/c/d deficient aortic endothelium to a similar extent as the Mef2s. This is consistent with the phenotypic similarity of Klf2/4 and Mef2a/c/d deletions. Comparison of genes altered by Klf2/4 and Mef2a/c/d deletions revealed that 37% of Mef2-dependent genes are also Klf2/4-dependent.

Conclusions: Together, these data support a model in which Mef2 transcription factors redundantly regulate endothelial expression of Klf2 and Klf4 in response to shear stress to promote atheroprotective gene expression. They further regulate expression of many genes important for endothelial function independently of Klf2/4.

[IgG(4)-related disease involving the trachea and paratracheal soft tissue: a case report and literature review]

Objective: To investigate the clinical data of a patient with IgG(4)-related disease involving the trachea and paratracheal soft tissue and review the literature so as to improve the understanding level of the disorder. Methods: To analyze the clinical manifestation, laboratory examination, imaging, histopathology, treatment and prognosis of a patient with IgG(4)-related disease trachea and paratracheal soft tissue involved, who was admitted to the Department of Respiratory and Critical Care Medicine at Beijing Chaoyang Hospital. The relevant literatures were reviewed. Results: A 18-year-old female was admitted with chief complaint of cough, dyspnea, and neck mass. Neck CT suggested that tracheal stenosis was caused by surrounded soft tissue. Paratracheal mass biopsy showed dense collagen fibers with infiltration of many lymphocytes and plasma cells. Immunohistochemical stain found that IgG(4)-positive plasma cells were >50/high power field (HPF) and a ratio of IgG(4)/IgG positive cells was over 40% .The level of serum IgG(4) was significantly increased (2 930 mg/L). She was diagnosed as IgG(4)-related disease. The patient was treated with 80 mg intravenous methylprednisolone per day for three days, then prednisone 40 mg daily oral. Her dyspnea was significantly relieved.One month later, CT scan showed that the cervical tracheal stenosis was significantly improved. We identified 20 cases of IgG(4)-related disease involving the trachea and paratracheal soft tissue from databases, in which only 1 case was similar as this patient. The other 19 cases were of extratracheal involvement. Elevated serum IgG(4) was detected in 11/12 patients. Most patients were treated with glucocorticoid, some combined with immunosuppressive agents and rituximab. The clinical outcome was good. Conclusion: IgG(4)-related disease involving the trachea and paratracheal soft tissue is a rare condition. Serum IgG(4) level and histopathology should be considered for diagnosis. Glucocorticoid is effective.

[Utility and evaluation of immunohistochemical detection of BRAF V600E mutation in melanoma]

Objective: To evaluate the sensitivity, specificity and clinical value of anti-BRAF V600E antibody (clone VE1) in detection of the BRAF V600E mutant in formalin-fixed and paraffin-embedded (FFPE) melanoma specimens by immunohistochemical (IHC) methods. Methods: A total of 50 melanoma samples collected between 2008 and 2016 from 40 patients were analyzed for BRAF mutation (exon 15) by DNA sequencing using FFPE. These tissues were immunostained with VE1 antibody, and the results were analyzed and compared with those by DNA sequencing. Results: By DNA sequencing, 36 cases showed BRAF mutation while others were BRAF wild type. Among the 36 cases with BRAF mutation, 32 harbored BRAF V600E, two harbored BRAF V600K, one had BRAF K601E and one had BRAF D594N, respectively. IHC staining showed 30 specimens were VE1 positive, while 19 were negative. The determination of IHC result for one case was obscured by heavy pigments. Of the BRAF-mutated specimens, four specimens with BRAF mutation other than V600E were all negative for VE1. The sensitivity and specificity of the VE1 immunostaining was 96.8% and 100.0% respectively.Concordance of BRAF V600E detection between immunostaining and DNA sequencing was 98.0%(48/49). Conclusions: High sensitivity and specificity for VE1 immunostaining in detecting BRAF V600E in melanomas are demonstrated. It is a rapid and cost-effective method for detecting BRAF V600E mutations in melanoma patients. Hence, VE1 immunostaining can be used as an important screening method for BRAF mutation in laboratories.

Endothelial Myocyte Enhancer Factor 2c Inhibits Migration of Smooth Muscle Cells Through Fenestrations in the Internal Elastic Lamina

OBJECTIVE

Laminar flow activates myocyte enhancer factor 2 (MEF2) transcription factors in vitro to induce expression of atheroprotective genes in the endothelium. Here we sought to establish the role of Mef2c in the vascular endothelium in vivo.

APPROACH AND RESULTS

To study endothelial Mef2c, we generated endothelial-specific deletion of Mef2c using Tie2-Cre or Cdh5-Cre-ER^T2 and examined aortas and carotid arteries by en face immunofluorescence. We observed enhanced actin stress fiber formation in the Mef2c-deleted thoracic aortic endothelium (laminar flow region), similar to those observed in normal aortic inner curvature (disturbed flow region). Furthermore, Mef2c deletion resulted in the de novo formation of subendothelial intimal cells expressing markers of differentiated smooth muscle in the thoracic aortas and carotids. Lineage tracing showed that these cells were not of endothelial origin. To define early events in intimal development, we induced endothelial deletion of Mef2c and examined aortas at 4 and 12 weeks postinduction. The number of intimal cell clusters increased from 4 to 12 weeks, but the number of cells within a cluster peaked at 2 cells in both cases, suggesting ongoing migration but minimal proliferation. Moreover, we identified cells extending from the media through fenestrations in the internal elastic lamina into the intima, indicating transfenestral smooth muscle migration. Similar transfenestral migration was observed in wild-type carotid arteries ligated to induce neointimal formation.

CONCLUSIONS

These results indicate that endothelial Mef2c regulates the endothelial actin cytoskeleton and inhibits smooth muscle cell migration into the intima.

Selective expression of TSPAN2 in vascular smooth muscle is independently regulated by TGF-β1/SMAD and myocardin/serum response factor

Tetraspanins (TSPANs) comprise a large family of 4-transmembrane domain proteins. The importance of TSPANs in vascular smooth muscle cells (VSMCs) is unexplored. Given that TGF-β1 and myocardin (MYOCD) are potent activators for VSMC differentiation, we screened for TGF-β1 and MYOCD/serum response factor (SRF)-regulated TSPANs in VSMC by using RNA-seq analyses and RNA-arrays. TSPAN2 was found to be the only TSPAN family gene induced by TGF-β1 and MYOCD, and reduced by SRF deficiency in VSMCs. We also found that TSPAN2 is highly expressed in smooth muscle-enriched tissues and down-regulated in in vitro models of VSMC phenotypic modulation. TSPAN2 expression is attenuated in mouse carotid arteries after ligation injury and in failed human arteriovenous fistula samples after occlusion by dedifferentiated neointimal VSMC. In vitro functional studies showed that TSPAN2 suppresses VSMC proliferation and migration. Luciferase reporter and chromatin immunoprecipitation assays demonstrated that TSPAN2 is regulated by 2 parallel pathways, MYOCD/SRF and TGF-β1/SMAD, via distinct binding elements within the proximal promoter. Thus, we identified the first VSMC-enriched and MYOCD/SRF and TGF-β1/SMAD-dependent TSPAN family member, whose expression is intimately associated with VSMC differentiation and negatively correlated with vascular disease. Our results suggest that TSPAN2 may play important roles in vascular disease.-Zhao, J., Wu, W., Zhang, W., Lu, Y. W., Tou, E., Ye, J., Gao, P., Jourd'heuil, D., Singer, H. A., Wu, M., Long, X. Selective expression of TSPAN2 in vascular smooth muscle is independently regulated by TGF-β1/SMAD and myocardin/serum response factor.

MEF2 transcription factors are key regulators of sprouting angiogenesis

Angiogenesis, the fundamental process by which new blood vessels form from existing ones, depends on precise spatial and temporal gene expression within specific compartments of the endothelium. However, the molecular links between proangiogenic signals and downstream gene expression remain unclear. During sprouting angiogenesis, the specification of endothelial cells into the tip cells that lead new blood vessel sprouts is coordinated by vascular endothelial growth factor A (VEGFA) and Delta-like ligand 4 (Dll4)/Notch signaling and requires high levels of Notch ligand DLL4. Here, we identify MEF2 transcription factors as crucial regulators of sprouting angiogenesis directly downstream from VEGFA. Through the characterization of a Dll4 enhancer directing expression to endothelial cells at the angiogenic front, we found that MEF2 factors directly transcriptionally activate the expression of Dll4 and many other key genes up-regulated during sprouting angiogenesis in both physiological and tumor vascularization. Unlike ETS-mediated regulation, MEF2-binding motifs are not ubiquitous to all endothelial gene enhancers and promoters but are instead overrepresented around genes associated with sprouting angiogenesis. MEF2 target gene activation is directly linked to VEGFA-induced release of repressive histone deacetylases and concurrent recruitment of the histone acetyltransferase EP300 to MEF2 target gene regulatory elements, thus establishing MEF2 factors as the transcriptional effectors of VEGFA signaling during angiogenesis.

Population genetic structure of critically endangered salamander (Hynobius amjiensis) in China: recommendations for conservation

Amji's salamander (Hynobius amjiensis) is a critically endangered species (IUCN Red List), which is endemic to mainland China. In the present study, five haplotypes were genotyped for the mtDNA cyt b gene in 45 specimens from three populations. Relatively low levels of haplotype diversity (h = 0.524) and nucleotide diversity (π = 0.00532) were detected. Analyses of the phylogenic structure of H. amjiensis showed no evidence of major geographic partitions or substantial barriers to historical gene flow throughout the species' range. Two major phylogenetic haplotype groups were revealed, and were estimated to have diverged about 1.262 million years ago. Mismatch distribution analysis, neutrality tests, and Bayesian skyline plots revealed no evidence of dramatic changes in the effective population size. According to the SAMOVA and STRUCTURE analyses, H. amjiensis should be regarded as two different management units.

Venous Endothelial Marker COUP-TFII Regulates the Distinct Pathologic Potentials of Adult Arteries and Veins

Arteries and veins have very different susceptibility to certain vascular diseases such as atherosclerosis and vascular calcification. The molecular mechanisms of these differences are not fully understood. In this study, we discovered that COUP-TFII, a transcription factor critical for establishing the venous identity during embryonic vascular development, also regulates the pathophysiological functions of adult blood vessels, especially those directly related to vascular diseases. Specifically, we found that suppression of COUP-TFII in venous ECs switched its phenotype toward pro-atherogenic by up-regulating the expression of inflammatory genes and down-regulating anti-thrombotic genes. ECs with COUP-TFII knockdown also readily undergo endothelial-to-mesenchymal transition (EndoMT) and subsequent osteogenic differentiation with dramatically increased osteogenic transcriptional program and calcium deposition. Consistently, over-expression of COUP-TFII led to the completely opposite effects. In vivo validation of these pro-atherogenic and osteogenic genes also demonstrates a broad consistent differential expression pattern in mouse aorta vs. vena cava ECs, which cannot be explained by the difference in hemodynamic flow. These data reveal phenotypic modulation by different levels of COUP-TFII in arterial and venous ECs, and suggest COUP-TFII may play an important role in the different susceptibilities of arteries and veins to vascular diseases such as atherosclerosis and vascular calcification.

Programmable and on-demand drug release using electrical stimulation

Recent advancement in microfabrication has enabled the implementation of implantable drug delivery devices with precise drug administration and fast release rates at specific locations. This article presents a membrane-based drug delivery device, which can be electrically stimulated to release drugs on demand with a fast release rate. Hydrogels with ionic model drugs are sealed in a cylindrical reservoir with a separation membrane. Electrokinetic forces are then utilized to drive ionic drug molecules from the hydrogels into surrounding bulk solutions. The drug release profiles of a model drug show that release rates from the device can be electrically controlled by adjusting the stimulated voltage. When a square voltage wave is applied, the device can be quickly switched between on and off to achieve pulsatile release. The drug dose released is then determined by the duration and amplitude of the applied voltages. In addition, successive on/off cycles can be programmed in the voltage waveforms to generate consistent and repeatable drug release pulses for on-demand drug delivery.

A modified Glasgow Blatchford Score improves risk stratification in upper gastrointestinal bleed: a prospective comparison of scoring systems

BACKGROUND

Several risk scoring systems exist for upper gastrointestinal bleed (UGIB). We hypothesised that a modified Glasgow Blatchford Score (mGBS) that eliminates the subjective components of the GBS might perform as well as current scoring systems.

AIM

To compare the performance of the mGBS to the most widely reported scoring systems for prediction of clinical outcomes in patients presenting with UGIB.

METHODS

Prospective cohort study from 9/2010 to 9/2011. Accuracy of the mGBS was compared with the full GBS, full Rockall Score (RS) and clinical RS using area under the receiver operating characterstics-curve (AUC). PRIMARY OUTCOME was need for clinical intervention: blood transfusion, endoscopic, radiological or surgical intervention. Secondary outcome was repeat bleeding or mortality.

RESULTS

One hundred and ninety-nine patients were included. Median age was 56 with 40% women. Thirty-two per cent patients required blood transfusion, 24% endoscopic interventions, 0.5% radiological intervention, 0 surgical interventions, 5% had repeat bleeding and 0.5% mortality.

PRIMARY OUTCOME

the mGBS (AUC 0.85) performed as well as the GBS (AUC = 0.86, P = 0.81), and outperformed the full RS (AUC 0.75, P = 0.005) and clinical RS (AUC 0.66, P < 0.0001). Secondary outcome: the mGBS (AUC 0.83) performed as well as the GBS (AUC 0.81, P = 0.38) and full RS (AUC 0.69, and outperformed the clinical RS (AUC 0.59, P = 0.0007).

CONCLUSIONS

The modified Glasgow Blatchford Score performed as well as the full Glasgow Blatchford Score while outperforming both Rockall Scores for prediction of clinical outcomes in American patients with upper gastrointestinal bleed. By eliminating the subjective components of the Glasgow Blatchford Score, the modified Glasgow Blatchford Score may be easier to use and therefore more easily implemented into routine clinical practice.

Osteoblast interactions with various hydroxyapatite based biomaterials consolidated using a spark plasma sintering technique

This study investigated the osteoblast behaviors on various hydroxyapatite based biomaterials that were consolidated at 1100 degrees C for 3 min by a spark plasma sintering technique. The osteoblasts from human fetal osteoblast cell line were cultured in the medium on the various biomaterials surfaces (HA, RF21, 1SiHA, and 5SiHA) to assess the cell morphology and proliferation as well as cell differentiation (alkaline phosphatase activity). Moreover, the bone gamma-carboxyglutamic protein or osteocalcin in the medium were determined at different periods of culture. The present results indicated that the amount of osteocalcin in the medium decreased during the periods of culture. The highest osteocalcin production obtained from the biomaterial 5SiHA after cell culture for 2 days demonstrated that the presence of silica in the biomaterials enhanced the cell differentiation by the rapid release of silicate and calcium ions.

A study on oxidative stress in lead-exposed workers

To explore the possible oxidative stress induced by lead, heparinized whole blood and urine of 66 secondary smelter lead workers (46 for Comet assay) and 28 controls were collected. The concentrations of blood lead (BPb) and urinary lead (UPb) and alpha-aminolevulinic acid (alpha-ALA), indices of lead exposure level of the body, were determined. Malondialdehyde (MDA) concentrations and superoxide dismutase (SOD) activity of plasma were also measured. Single-cell gel (SCG, Comet assay) was used to measure the DNA damage of peripheral blood cells. There was a positive correlation between the presence of Pb in blood and significant increases in MDA levels and SOD activity. Alcohol consumption and smoking with increased exposure to Pb was associated with enhanced DNA damage. A positive correlation was found between MDA and DNA damage.

A preliminary study of the mental health of young migrant workers in Shenzhen

The aim of this study is to examine the mental health status of young migrant workers in Shenzhen. Using the Symptoms Check List-90 (SCL-90), Eysenck Personality Questionnaire, Social Support Scale and Mental Health Questionnaire for Laborers, 371 migrant workers who came from inland areas of China and 100 local workers were investigated. The SCL-90 profile of migrant workers was also compared to the SCL-90 norms provided by general people in China. The SCL-90 results showed that the total scores, the average scores of the positive symptoms, the three factor scores of obsessionality, interpersonal sensitivity and phobia in migrant workers were significantly higher than those in the local workers. According to the multivariate analysis, the amount of contribution to mental health, in descending order, was neuroticism, psychological pressure, income, home sickness, marital or love problems, extroversion and introversion, living conditions and social status. The mental health status of young migrant workers in Shenzhen was poorer than that of their local counterparts, as well as people in China on the SCL-90. It is recommended that mental health workers should help migrant workers adjust to the new urban environment by providing psychological counseling and other relevant treatment facilities.

[Effect of extracorporeal shock wave lithotripsy on renal function-an experience with the new type piezoelectric lithotripter, Therasonic]

Seventeen patients with renal stones and 17 patients with ureteral stones were treated using the newly developed piezoelectric shock wave lithotripter, THERASONIC. To determine the effect of shock wave on renal function, urinary N-acetyl-beta-D-glucosaminidase (NAG) activity, urinary beta 2 microglobulin (BMG) concentration, serum BMG concentration and creatinine clearance (Ccr) were measured. Urinary NAG activity and urinary BMG concentration in renal stone patients were significantly elevated immediately after the treatment and returned to the pretreatment value within 24 hours. Neither serum BMG nor Ccr showed significant change in any of the patients. Therefore, we conclude that the renal tubular damage, which is transient and subtle, is the effect of shock wave lithotripsy using THERASONIC machine.

[Treatment of urinary stones with Therasonic, the third generation piezoelectric shock wave lithotripter]

The THERASONIC lithotripsy treatment system, a newly developed piezoelectric lithotripter, uses both an X-ray and ultrasound system and enables stone localization effective. Treatment of urinary stones with THERASONIC was begun in June, 1989 and 57 treatments have already been performed on 38 patients. Successful treatment, defined as either stone free or with a residual stone less than 4 mm in diameter on flat X-ray film, was accomplished in 95% of the renal stones and over 50% of the ureteral stones. The overall success rate was 74%. Blood pressure and laboratory values did not show any significant change during or after the treatment. No major complication has been observed except for one perirenal hematoma which was resolved with conservative therapy.