bluuebunny/crossref_metadata_2025 huggingface dataset:
Peptide-Based Vaccination Therapy for Rheumatic Diseases
Authors: Wang Bin , Chen Shiju , Zheng Qing , Liu Yuan , Shi Guixiu
Published: March 2020

Rheumatic diseases are extremely heterogeneous diseases with substantial risks of morbidity and mortality, and there is a pressing need in developing more safe and cost-effective treatment strategies. Peptide-based vaccination is a highly desirable strategy in treating noninfection diseases, such as cancer and autoimmune diseases, and has gained increasing attentions. This review is aimed at providing a brief overview of the recent advances in peptide-based vaccination therapy for rheumatic diseases. Tremendous efforts have been made to develop effective peptide-based vaccinations against rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), while studies in other rheumatic diseases are still limited. Peptide-based active vaccination against pathogenic cytokines such as TNF-αand interferon-α(IFN-α) is shown to be promising in treating RA or SLE. Moreover, peptide-based tolerogenic vaccinations also have encouraging results in treating RA or SLE. However, most studies available now have been mainly based on animal models, while evidence from clinical studies is still lacking. The translation of these advances from experimental studies into clinical therapy remains impeded by some obstacles such as species difference in immunity, disease heterogeneity, and lack of safe delivery carriers or adjuvants. Nevertheless, advances in high-throughput technology, bioinformatics, and nanotechnology may help overcome these impediments and facilitate the successful development of peptide-based vaccination therapy for rheumatic diseases.
Exercise-Induced Cognitive Improvement Is Associated with Sodium Channel-Mediated Excitability in APP/PS1 Mice
Authors: Tan Ya-Xin , Liu Guang-Cai , Chen Hong-Lan , Lu Min-Nan , Chen Bo , Hu Tao , Zhang Li , Mao Rui , Li Shan , Mei Rong , Wang Xu-Yang , Xiyang Yan-Bin
Published: March 2020

Elevated brain activation, or hyperexcitability, induces cognitive impairment and confers an increased risk of Alzheimer’s disease (AD). Blocking the overexcitation of the neural network may be a promising new strategy to prevent, halt, and even reverse this condition. Physical exercise has been shown to be an effective cognitive enhancer that reduces the risk of AD in elderly individuals, but the underlying mechanisms are far from being fully understood. We explored whether long-term treadmill exercise attenuates amyloid precursor protein (APP)/presenilin-1 (PS1) mutation-induced aberrant network activity and thus improves cognition by altering the numbers and/or distribution of voltage-gated sodium channels (Nav) in transgenic mice. APP/PS1 mice aged 2, 3.5, 5, 6.5, 8, and 9 months underwent treadmill exercise with different durations or at different stages of AD. The alterations in memory, electroencephalogram (EEG) recordings, and expression levels and distributions of Nav functional members (Nav1.1α, Nav1.2, Nav1.6, and Navβ2) were evaluated. The results revealed that treadmill exercise with 12- and 24-week durations 1) induced significant improvement in novel object recognition (NOR) memory and Morris water maze (MWM) spatial memory; 2) partially reduced abnormal spike activity; and 3) redressed the disturbed cellular distribution of Nav1.1α, aberrant Navβ2 cleavage augmentation, and Nav1.6 upregulation. Additionally, APP/PS1 mice in the 24-week exercise group showed better performance in the NOR task and a large decrease in Nav1.6 expression, which was close to the wild-type level. This study suggests that exercise improves cognition and neural activity by altering the numbers and distribution of hippocampal Nav in APP/PS1 mice. Long-term treadmill exercise, for about 24 weeks, starting in the preclinical stage, is a promising therapeutic strategy for preventing AD and halting its progress.
A Degrading Potassium Tablet Mimicking Active Gastric Bleeding in a Computer Tomographic Investigation
Authors: Commandeur J. P. , Metwaly A. , Büchler L. , Speiser J. , Brander L. , Reintam Blaser A.
Published: March 2020

A 54-year-old male patient was admitted to the hospital due to symptoms caused by an intramural hematoma of the descending aorta. In a contrast media-enhanced computed tomography scan performed five days after admission to evaluate dynamics of the hematoma, a hyperdense lesion was seen in the stomach. A suspicion of gastric hemorrhage was raised at the first evaluation. Because the patient’s clinical condition and hemoglobin levels were stable, gastroscopy to rule out an aorto-gastric fistula or another type of bleeding was not undertaken. In the secondary evaluation of the history and images, it became clear that the hyperdense lesion mimicking bleeding in the stomach must have been caused by a degrading potassium tablet ingested by the patient five hours before the investigation.
Genetic Predictors of Circulating 25-Hydroxyvitamin D and Prognosis after Colorectal Cancer
Authors: Neumeyer Sonja , Butterbach Katja , Banbury Barbara L. , Berndt Sonja I. , Campbell Peter T. , Chlebowski Rowan T. , Chan Andrew T. , Giovannucci Edward L. , Joshi Amit D. , Ogino Shuji , Song Mingyang , McCullough Marjorie L. , Maalmi Haifa , Manson JoAnn E. , Sakoda Lori C. , Schoen Robert E. , Slattery Martha L. , White Emily , Win Aung K. , Figueiredo Jane C. , Hopper John L. , Macrae Finlay A. , Peters Ulrike , Brenner Hermann , Hoffmeister Michael , Newcomb Polly A. , Chang-Claude Jenny
Published: March 2020

Background:

Low serum 25-hydroxyvitamin D [25(OH)D] concentrations in patients with colorectal cancer have been consistently associated with higher mortality in observational studies. It is unclear whether low 25(OH)D levels directly influence colorectal cancer mortality. To minimize bias, we use genetic variants associated with vitamin D levels to evaluate the association with overall and colorectal cancer–specific survival.

Methods:

Six genetic variants have been robustly identified to be associated with 25(OH)D levels in genome-wide association studies. On the basis of data from the International Survival Analysis in Colorectal Cancer Consortium, the individual genetic variants and a weighted genetic risk score were tested for association with overall and colorectal cancer–specific survival using Cox proportional hazards models in 7,657 patients with stage I to IV colorectal cancer, of whom 2,438 died from any cause and 1,648 died from colorectal cancer.

Results:

The 25(OH)D decreasing allele of SNP rs2282679 (GC gene, encodes group-specific component/vitamin D–binding protein) was associated with poorer colorectal cancer–specific survival, although not significant after multiple-testing correction. None of the other five SNPs showed an association. The genetic risk score showed nonsignificant associations with increased overall [HR = 1.54; confidence interval (CI), 0.86–2.78] and colorectal cancer–specific mortality (HR = 1.76; 95% CI, 0.86–3.58). A significant increased risk of overall mortality was observed in women (HR = 3.26; 95% CI, 1.45–7.33; Pheterogeneity = 0.01) and normal-weight individuals (HR = 4.14; 95% CI, 1.50–11.43, Pheterogeneity = 0.02).

Conclusions:

Our results provided little evidence for an association of genetic predisposition of lower vitamin D levels with increased overall or colorectal cancer–specific survival, although power might have been an issue.

Impact:

Further studies are warranted to investigate the association in specific subgroups.
Type I IFN, Ly6C+ cells, and Phagocytes Support Suppression of Peritoneal Carcinomatosis Elicited by a TLR and CLR Agonist Combination
Authors: Dyevoich Allison M. , Haas Karen M.
Published: March 2020

Metastatic cancer involving spread to the peritoneal cavity is referred to as peritoneal carcinomatosis and has a very poor prognosis. Our previous study demonstrated a Toll-like receptor and C-type lectin receptor agonist pairing of monophosphoryl lipid A (MPL) and trehalose-6,6′-dicorynomycolate (TDCM) effectively inhibits tumor growth and ascites development following TA3-Ha and EL4 challenge through a mechanism dependent on B-1a cell–produced natural IgM and complement. In this study, we investigated additional players in the MPL/TDCM-elicited response. MPL/TDCM treatment rapidly increased type I IFN levels in the peritoneal cavity along with myeloid cell numbers, including macrophages and Ly6Chi monocytes. Type I IFN receptor (IFNAR1−/−) mice produced tumor-reactive IgM following MPL/TDCM treatment, but failed to recruit Ly6C+ monocytes and were not afforded protection during tumor challenges. Clodronate liposome depletion of phagocytic cells, as well as targeted depletion of Ly6C+ cells, also ablated MPL/TDCM-induced protection. Cytotoxic mediators known to be produced by these cells were required for effects. TNFα was required for effective TA3-Ha killing and nitric oxide was required for EL4 killing. Collectively, these data reveal a model whereby MPL/TDCM-elicited antitumor effects strongly depend on innate cell responses, with B-1a cell–produced tumor-reactive IgM and complement pairing with myeloid cell–produced cytotoxic mediators to effectively eradicate tumors in the peritoneal cavity.
Global Regulation of the Histone Mark H3K36me2 Underlies Epithelial Plasticity and Metastatic Progression
Authors: Yuan Salina , Natesan Ramakrishnan , Sanchez-Rivera Francisco J. , Li Jinyang , Bhanu Natarajan V. , Yamazoe Taiji , Lin Jeffrey H. , Merrell Allyson J. , Sela Yogev , Thomas Stacy K. , Jiang Yanqing , Plesset Jacqueline B. , Miller Emma M. , Shi Junwei , Garcia Benjamin A. , Lowe Scott W. , Asangani Irfan A. , Stanger Ben Z.
Published: March 2020

Epithelial plasticity, reversible modulation of a cell's epithelial and mesenchymal features, is associated with tumor metastasis and chemoresistance, leading causes of cancer mortality. Although different master transcription factors and epigenetic modifiers have been implicated in this process in various contexts, the extent to which a unifying, generalized mechanism of transcriptional regulation underlies epithelial plasticity remains largely unknown. Here, through targeted CRISPR/Cas9 screening, we discovered two histone-modifying enzymes involved in the writing and erasing of H3K36me2 that act reciprocally to regulate epithelial-to-mesenchymal identity, tumor differentiation, and metastasis. Using a lysine-to-methionine histone mutant to directly inhibit H3K36me2, we found that global modulation of the mark is a conserved mechanism underlying the mesenchymal state in various contexts. Mechanistically, regulation of H3K36me2 reprograms enhancers associated with master regulators of epithelial-to-mesenchymal state. Our results thus outline a unifying epigenome-scale mechanism by which a specific histone modification regulates cellular plasticity and metastasis in cancer.

Significance:

Although epithelial plasticity contributes to cancer metastasis and chemoresistance, no strategies exist for pharmacologically inhibiting the process. Here, we show that global regulation of a specific histone mark, H3K36me2, is a universal epigenome-wide mechanism that underlies epithelial-to-mesenchymal transition and mesenchymal-to-epithelial transition in carcinoma cells. These results offer a new strategy for targeting epithelial plasticity in cancer.

This article is highlighted in the In This Issue feature, p. 747
Mutations in the RNA Splicing Factor SF3B1 Promote Tumorigenesis through MYC Stabilization
Authors: Liu Zhaoqi , Yoshimi Akihide , Wang Jiguang , Cho Hana , Chun-Wei Lee Stanley , Ki Michelle , Bitner Lillian , Chu Timothy , Shah Harshal , Liu Bo , Mato Anthony R. , Ruvolo Peter , Fabbri Giulia , Pasqualucci Laura , Abdel-Wahab Omar , Rabadan Raul
Published: March 2020

Although mutations in the gene encoding the RNA splicing factor SF3B1 are frequent in multiple cancers, their functional effects and therapeutic dependencies are poorly understood. Here, we characterize 98 tumors and 12 isogenic cell lines harboring SF3B1 hotspot mutations, identifying hundreds of cryptic 3′ splice sites common and specific to different cancer types. Regulatory network analysis revealed that the most common SF3B1 mutation activates MYC via effects conserved across human and mouse cells. SF3B1 mutations promote decay of transcripts encoding the protein phosphatase 2A (PP2A) subunit PPP2R5A, increasing MYC S62 and BCL2 S70 phosphorylation which, in turn, promotes MYC protein stability and impair apoptosis, respectively. Genetic PPP2R5A restoration or pharmacologic PP2A activation impaired SF3B1-mutant tumorigenesis, elucidating a therapeutic approach to aberrant splicing by mutant SF3B1.

Significance:

Here, we identify that mutations in SF3B1, the most commonly mutated splicing factor gene across cancers, alter splicing of a specific subunit of the PP2A serine/threonine phosphatase complex to confer post-translational MYC and BCL2 activation, which is therapeutically intervenable using an FDA-approved drug.

See related commentary by O'Connor and Narla, p. 765.

This article is highlighted in the In This Issue feature, p. 747
Two Abnormal Cell Lines of Trisomy 14 and t(X;14) with Skewed X-Inactivation
Authors: Mohamed Amal M. , Eid Maha M. , Eid Ola M. , Hussein Shymaa H. , Mossaad Aida M. , Abdelfattah Usama , Sharafuddin Mohab A. , El Halafawy Yasser M. , Elbanoby Tarek M. , Abdel-Salam Ghada M.H.
Published: March 2020

Trisomy 14 is incompatible with live, but there are several patients reported with mosaic trisomy 14. We aimed to study the pattern of X inactivation and its effect on a translocated autosome and to find out an explanation of the involvement of chromosome 14 in 2 different structural chromosomal abnormalities. We report on a girl with frontal bossing, hypertelorism, low-set ears, micrognathia, cleft palate, congenital heart disease, and abnormal skin pigmentations. The patient displayed iris, choroidal, and retinal coloboma and agenesis of the corpus callosum and cerebellar vermis hypoplasia. Cytogenetic analysis revealed a karyotype 45,X,der(X)t(X;14)(q24;q11)[85]/46,XX,rob(14;14)(q10;q10),+14[35]. Array-CGH for blood and buccal mucosa showed high mosaic trisomy 14 and an Xq deletion. MLPA detected trisomy 14 in blood and buccal mucosa and also showed normal methylation of the imprinting center. FISH analysis confirmed the cell line with trisomy 14 (30%) and demonstrated the mosaic deletion of the Xq subtelomere in both tissues. There was 100% skewed X inactivation for the t(X;14). SNP analysis of the patient showed no region of loss of heterozygosity on chromosome 14. Also, genotype call analysis of the patient and her parents showed heterozygous alleles of chromosome 14 with no evidence of uniparental disomy. Our patient had a severe form of mosaic trisomy 14. We suggest that this cytogenetic unique finding that involved 2 cell lines with structural abnormalities of chromosome 14 occurred in an early postzygotic division. These 2 events may have happened separately or maybe there is a kind of trisomy or monosomy rescue due to dynamic cytogenetic interaction between different cell lines to compensate for gene dosage.
Nanoparticles in Gastrooncology
Authors: Jefremow André , Neurath Markus F.
Published: March 2020

Background: Gastrointestinal malignancies have the greatest incidence and cancer-associated death rates worldwide. Routine therapeutic modalities include surgery, chemotherapy and radiation but they often fail to reach the goal of cancer-free survival. Summary: In the light of this urgent medical need for the treatment of GI tumors, nanotech­nology-based approaches, i.e. nanomedicine, promise new therapeutic options. Using nanoparticles instead of classically designed drugs, targeting anticancer agents directly to the tumor site may revolutionize both diagnostic and therapeutic tools thereby facilitating the identification and elimination of malignant cells. Importantly, diagnostic insight and therapeutic effects can be achieved simultaneously through the same nanoparticle. Additionally, a nanoparticle may be loaded with more than one agent, thereby further increasing the value and power of the nanotechnology approach in oncologic therapeutic concepts. Although most insight into mechanisms of nanomedicine has been gained from in vitro and preclinical in vivo models, few clinical trials have been conducted, and nanomedicine-based concepts are already part of standard treatment algorithms. However, despite substantial progress it remains a challenge to design nanoparticles that feature all desirable characteristics at the same time. Key Messages: This review seeks to provide substantial insight into the current status of nanomedicine-based approaches employed for diagnostic and/or therapeutic purposes in the field of gastrointestinal cancers by highlighting achievements and pointing out unresolved issues that need to be further addressed by future research attempts.
HuR (Human Antigen R) Regulates the Contraction of Vascular Smooth Muscle and Maintains Blood Pressure
Authors: Liu Shanshan , Jiang Xiuxin , Lu Hanlin , Xing Mengdan , Qiao Yanning , Zhang Cheng , Zhang Wencheng
Published: March 2020

Objective:

HuR (human antigen R)—an RNA-binding protein—is involved in regulating mRNA stability by binding adenylate-uridylate–rich elements. This study explores the role of HuR in the regulation of smooth muscle contraction and blood pressure.

Approach and Results:

Vascular HuR
SMKO
(smooth muscle–specific HuR knockout) mice were generated by crossbreeding HuR
flox/flox
mice with α-SMA (α-smooth muscle actin)-Cre mice. As compared with CTR (control) mice, HuR
SMKO
mice showed hypertension and cardiac hypertrophy. HuR levels were decreased in aortas from hypertensive patients and SHRs (spontaneously hypertensive rats), and overexpression of HuR could lower the blood pressure of SHRs. Contractile response to vasoconstrictors was increased in mesenteric artery segments isolated from HuR
SMKO
mice. The functional abnormalities in HuR
SMKO
mice were attributed to decreased mRNA and protein levels of RGS (regulator of G-protein signaling) protein(s) RGS2, RGS4, and RGS5, which resulted in increased intracellular calcium increase. Consistently, the degree of intracellular calcium ion increase in HuR-deficient smooth muscle cells was reduced by overexpression of RGS2, RGS4, or RGS5. Finally, administration of RGS2 and RGS5 reversed the elevated blood pressure in HuR
SMKO
mice.

Conclusions:

Our findings indicate that HuR regulates vascular smooth muscle contraction and maintains blood pressure by modulating RGS expression.
Myristoylation of LMCD1 Leads to Its Species-Specific Derepression of E2F1 and NFATc1 in the Modulation of CDC6 and IL-33 Expression During Development of Vascular Lesions
Authors: Govatati Suresh , Pichavaram Prahalathan , Janjanam Jagadeesh , Guo Liang , Virmani Renu , Rao Gadiparthi N.
Published: March 2020

Objective:

In view of our previous observations on differential expression of LMCD1 (LIM and cysteine-rich domains 1) in human versus rodents, we asked the question whether LMCD1 plays a species-specific role in the development of vascular lesions.

Approach and Results:

A combination of genetic, molecular, cellular, and disease models were used to test species-specific role of LMCD1 in the pathogenesis of vascular lesions. Here, we report species-specific regulation of LMCD1 expression in mediating vascular smooth muscle cell proliferation and migration during vascular wall remodeling in humans versus mice. Thrombin induced LMCD1 expression in human aortic smooth muscle cells but not mouse aortic smooth muscle cells via activation of Par1 (protease-activated receptor 1)-Gαq/11 (Gα protein q/11)-PLCβ3 (phospholipase Cβ3)-NFATc1 (nuclear factor of activated T cells 1) signaling. Furthermore, although LMCD1 mediates thrombin-induced proliferation and migration of both human aortic smooth muscle cells and mouse aortic smooth muscle cells via influencing E2F1 (E2F transcription factor 1)-mediated CDC6 (cell division cycle 6) expression and NFATc1-mediated IL (interleukin)-33 expression, respectively, in humans, it acts as an activator, and in mice, it acts as a repressor of these transcriptional factors. Interestingly, LMCD1 repressor activity was nullified by N-myristoyltransferase 2–mediated myristoylation in mouse. Besides, we found increased expression of LMCD1 in human stenotic arteries as compared to nonstenotic arteries. On the other hand, LMCD1 expression was decreased in neointimal lesions of mouse injured arteries as compared to noninjured arteries.

Conclusions:

Together, these observations reveal that LMCD1 acts as an activator and repressor of E2F1 and NFATc1 in humans and mice, respectively, in the induction of CDC6 and IL-33 expression during development of vascular lesions. Based on these findings, LMCD could be a potential target for drug development against restenosis and atherosclerosis in humans.
Telecommunicator Cardiopulmonary Resuscitation: A Policy Statement From the American Heart Association
Authors: Kurz Michael Christopher , Bobrow Bentley J. , Buckingham Julie , Cabanas Jose G. , Eisenberg Mickey , Fromm Peter , Panczyk Micah J. , Rea Tom , Seaman Kevin , Vaillancourt Christian ,   On behalf of the American Heart Association Advocacy Coordinating Committee
Published: March 2020

Every year in the United States, >350 000 people have sudden cardiac arrest outside of a hospital environment. Sudden cardiac arrest is the unexpected loss of heart function, breathing, and consciousness and is commonly the result of an electric disturbance in the heart. Unfortunately, only ≈1 in 10 victims survives this dramatic event. Early access to 9-1-1 and early cardiopulmonary resuscitation (CPR) are the first 2 links in the chain of survival for out-of-hospital cardiac arrest. Although 9-1-1 is frequently accessed, in the majority of cases, individuals with out-of-hospital cardiac arrest do not receive lay rescuer CPR and wait for the arrival of professional emergency rescuers. Telecommunicators are the true first responders and a critical link in the cardiac arrest chain of survival. In partnership with the 9-1-1 caller, telecommunicators have the first opportunity to identify a patient in cardiac arrest and provide initial care by delivering CPR instructions while quickly dispatching emergency medical services. The telecommunicator and the caller form a unique team in which the expertise of the telecommunicator is provided just in time to a willing caller, transforming the caller into a lay rescuer delivering CPR. The telecommunicator CPR (T-CPR) process, also previously described as dispatch CPR, dispatch-assisted CPR, or telephone CPR, represents an important opportunity to improve survival from sudden cardiac arrest. Conversely, failure to provide T-CPR in this manner results in preventable harm. This statement describes the public health impact of out-of-hospital cardiac arrest, provides guidance and resources to construct and maintain a T-CPR program, outlines the minimal acceptable standards for timely and high-quality delivery of T-CPR instructions, and identifies strategies to overcome common implementation barriers to T-CPR.
Crystal Clots as Therapeutic Target in Cholesterol Crystal Embolism
Authors: Shi Chongxu , Kim Tehyung , Steiger Stefanie , Mulay Shrikant R. , Klinkhammer Barbara M. , Bäuerle Tobias , Melica Maria Elena , Romagnani Paola , Möckel Diana , Baues Maike , Yang Luying , Brouns Sanne L.N. , Heemskerk Johan W. M. , Braun Attila , Lammers Twan , Boor Peter , Anders Hans-Joachim
Published: March 2020

Rationale:

Cholesterol crystal embolism can be a life-threatening complication of advanced atherosclerosis. Pathophysiology and molecular targets for treatment are largely unknown.

Objective:

We aimed to develop a new animal model of cholesterol crystal embolism to dissect the molecular mechanisms of cholesterol crystal (CC)–driven arterial occlusion, tissue infarction, and organ failure.

Methods and Results:

C57BL/6J mice were injected with CC into the left kidney artery. Primary end point was glomerular filtration rate (GFR). CC caused crystal clots occluding intrarenal arteries and a dose-dependent drop in GFR, followed by GFR recovery within 4 weeks, that is, acute kidney disease. In contrast, the extent of kidney infarction was more variable. Blocking necroptosis using mixed lineage kinase domain–like deficient mice or necrostatin-1s treatment protected from kidney infarction but not from GFR loss because arterial obstructions persisted, identifying crystal clots as a primary target to prevent organ failure. CC involved platelets, neutrophils, fibrin, and extracellular DNA. Neutrophil depletion or inhibition of the release of neutrophil extracellular traps had little effects, but platelet P2Y12 receptor antagonism with clopidogrel, fibrinolysis with urokinase, or DNA digestion with recombinant DNase I all prevented arterial occlusions, GFR loss, and kidney infarction. The window-of-opportunity was <3 hours after CC injection. However, combining Nec-1s (necrostatin-1s) prophylaxis given 1 hour before and DNase I 3 hours after CC injection completely prevented kidney failure and infarcts. In vitro, CC did not directly induce plasmatic coagulation but induced neutrophil extracellular trap formation and DNA release mainly from kidney endothelial cells, neutrophils, and few from platelets. CC induced ATP release from aggregating platelets, which increased fibrin formation in a DNase-dependent manner.

Conclusions:

CC embolism causes arterial obstructions and organ failure via the formation of crystal clots with fibrin, platelets, and extracellular DNA as critical components. Therefore, our model enables to unravel the pathogenesis of the CC embolism syndrome as a basis for both prophylaxis and targeted therapy.
The Noonan Syndrome Gene
Lztr1
Controls Cardiovascular Function by Regulating Vesicular Trafficking
Authors: Sewduth Raj Nayan , Pandolfi Silvia , Steklov Mikhail , Sheryazdanova Aidana , Zhao Peihua , Criem Nathan , Baietti Maria F. , Lechat Benoit , Quarck Rozeen , Impens Francis , Sablina Anna A.
Published: March 2020

Rationale:

Noonan syndrome (NS) is one of the most frequent genetic disorders. Bleeding problems are among the most common, yet poorly defined complications associated with NS. A lack of consensus on the management of bleeding complications in patients with NS indicates an urgent need for new therapeutic approaches.

Objective:

Bleeding disorders have recently been described in patients with NS harboring mutations of LZTR1 (leucine zipper-like transcription regulator 1), an adaptor for CUL3 (CULLIN3) ubiquitin ligase complex. Here, we assessed the pathobiology of LZTR1-mediated bleeding disorders.

Methods and Results:

Whole-body and vascular specific knockout of
Lztr1
results in perinatal lethality due to cardiovascular dysfunction.
Lztr1
deletion in blood vessels of adult mice leads to abnormal vascular leakage. We found that defective adherent and tight junctions in
Lztr1
-depleted endothelial cells are caused by dysregulation of vesicular trafficking. LZTR1 affects the dynamics of fusion and fission of recycling endosomes by controlling ubiquitination of the ESCRT-III (endosomal sorting complex required for transport III) component CHMP1B (charged multivesicular protein 1B), whereas NS-associated
LZTR1
mutations diminish CHMP1B ubiquitination. LZTR1-mediated dysregulation of CHMP1B ubiquitination triggers endosomal accumulation and subsequent activation of VEGFR2 (vascular endothelial growth factor receptor 2) and decreases blood levels of soluble VEGFR2 in
Lztr1
haploinsufficient mice. Inhibition of VEGFR2 activity by cediranib rescues vascular abnormalities observed in
Lztr1
knockout mice

Conclusions:

Lztr1
deletion phenotypically overlaps with bleeding diathesis observed in patients with NS. ELISA screening of soluble VEGFR2 in the blood of
LZTR1
-mutated patients with NS may predict both the severity of NS phenotypes and potential responders to anti-VEGF therapy. VEGFR inhibitors could be beneficial for the treatment of bleeding disorders in patients with NS.
PTH/PTHrP Receptor Signaling Restricts Arterial Fibrosis in Diabetic LDLR
−/−
Mice by Inhibiting Myocardin-Related Transcription Factor Relays
Authors: Behrmann Abraham , Zhong Dalian , Li Li , Cheng Su-Li , Mead Megan , Ramachandran Bindu , Sabaeifard Parastoo , Goodarzi Mohammad , Lemoff Andrew , Kronenberg Henry M. , Towler Dwight A.
Published: March 2020

Rationale:

The PTH1R (PTH [parathyroid hormone]/PTHrP [PTH-related protein] receptor) is expressed in vascular smooth muscle (VSM) and increased VSM PTH1R signaling mitigates diet-induced arteriosclerosis in LDLR
−/−
mice.

Objective:

To study the impact of VSM PTH1R deficiency, we generated mice SM22-Cre:PTH1R(fl/fl);LDLR
−/−
mice (PTH1R-VKO) and Cre-negative controls.

Methods and Results:

Immunofluorescence and Western blot confirmed PTH1R expression in arterial VSM that was reduced by Cre-mediated knockout. PTH1R-VKO cohorts exhibited increased aortic collagen accumulation in vivo, and VSM cultures from PTH1R-VKO mice elaborated more collagen (2.5-fold;
P
=0.01) with elevated
Col3a1
and
Col1a1
expression. To better understand these profibrotic responses, we performed mass spectrometry on nuclear proteins extracted from Cre-negative controls and PTH1R-VKO VSM. PTH1R deficiency reduced Gata6 but upregulated the MADS (MCM1, Agamous, Deficiens, and Srf DNA-binding domain)-box transcriptional co-regulator, Mkl-1 (megakaryoblastic leukemia [translocation] 1). Co-transfection assays (
Col3a1
promoter-luciferase reporter) confirmed PTH1R-mediated inhibition and Mkl-1-mediated activation of
Col3a1
transcription. Regulation mapped to a conserved hybrid CT(A/T)
6
GG MADS-box cognate in the
Col3a1
promoter. Mutations of C/G in this motif markedly reduced
Col3a1
transcriptional regulation by PTH1R and Mkl-1. Upregulation of
Col3a1
and
Col1a1
in PTH1R-VKO VSM was inhibited by small interfering RNA targeting
Mkl1
and by treatment with the Mkl-1 antagonist CCG1423 or the Rock (Rho-associated coiled-coil containing protein kinase)-2 inhibitor KD025. Chromatin precipitation demonstrated that VSM PTH1R deficiency increased Mkl-1 binding to
Col3a1 and Col1a1
, but not
TNF
, promoters. Proteomic studies of plasma extracellular vesicles and VSM from PTH1R-VKO mice identified C1r (complement component 1, r) and C1s (complement component 1, s), complement proteins involved in vascular collagen metabolism, as potential biomarkers. VSM C1r protein and
C1r
message were increased with PTH1R deficiency, mediated by Mkl-1-dependent transcription and inhibited by CCG1423 or KD025.

Conclusions:

PTH1R signaling restricts collagen production in the VSM lineage, in part, via Mkl-1 regulatory circuits that control collagen gene transcription. Strategies that maintain homeostatic VSM PTH1R signaling, as reflected in extracellular vesicle biomarkers of VSM PTH1R/Mkl-1 action, may help mitigate arteriosclerosis and vascular fibrosis.
EHD1 Modulates Cx43 Gap Junction Remodeling Associated With Cardiac Diseases
Authors: Martins-Marques Tania , Catarino Steve , Gonçalves Alexandre , Miranda-Silva Daniela , Gonçalves Lino , Antunes Pedro , Coutinho Gonçalo , Leite Moreira Adelino , Falcão Pires Inês , Girão Henrique
Published: March 2020

Rationale:

Efficient communication between heart cells is vital to ensure the anisotropic propagation of electrical impulses, a function mainly accomplished by gap junctions (GJ) composed of Cx43 (connexin 43). Although the molecular mechanisms remain unclear, altered distribution and function of gap junctions have been associated with acute myocardial infarction and heart failure.

Objective:

A recent proteomic study from our laboratory identified EHD1 (Eps15 [endocytic adaptor epidermal growth factor receptor substrate 15] homology domain-containing protein 1) as a novel interactor of Cx43 in the heart.

Methods and Results:

In the present work, we demonstrate that knockdown of EHD1 impaired the internalization of Cx43, preserving gap junction-intercellular coupling in cardiomyocytes. Interaction of Cx43 with EHD1 was mediated by Eps15 and promoted by phosphorylation and ubiquitination of Cx43. Overexpression of wild-type EHD1 accelerated internalization of Cx43 and exacerbated ischemia-induced lateralization of Cx43 in isolated adult cardiomyocytes. In addition, we show that EHDs associate with Cx43 in human and murine failing hearts.

Conclusions:

Overall, we identified EHDs as novel regulators of endocytic trafficking of Cx43, participating in the pathological remodeling of gap junctions, paving the way to innovative therapeutic strategies aiming at preserving intercellular communication in the heart.
Mitral Valve Prolapse, Ventricular Arrhythmias, and Sudden Death
Authors: Basso Cristina , Iliceto Sabino , Thiene Gaetano , Perazzolo Marra Martina
Published: March 2020

Despite a 2% to 3% prevalence of echocardiographically defined mitral valve prolapse (MVP) in the general population, the actual burden, risk stratification, and treatment of the so-called arrhythmic MVP are unknown. The clinical profile is characterized by a patient, usually female, with mostly bileaflet myxomatous disease, mid-systolic click, repolarization abnormalities in the inferior leads, and complex ventricular arrhythmias with polymorphic/right bundle branch block morphology, without significant regurgitation. Among the various pathophysiologic mechanisms of electrical instability, left ventricular fibrosis in the papillary muscles and inferobasal wall, mitral annulus disjunction, and systolic curling have been recently described by pathological and cardiac magnetic resonance studies in sudden death victims and patients with arrhythmic MVP. In addition, premature ventricular beats arising from the Purkinje tissue as ventricular fibrillation triggers have been documented by electrophysiologic studies in MVP patients with aborted sudden death.

The genesis of malignant ventricular arrhythmias in MVP probably recognizes the combination of the substrate (regional myocardial hypertrophy and fibrosis, Purkinje fibers) and the trigger (mechanical stretch) eliciting premature ventricular beats because of a primary morphofunctional abnormality of the mitral valve annulus.

The main clinical challenge is how to identify patients with arrhythmic MVP (which imaging technique and in which patient) and how to treat them to prevent sudden death. Thus, there is a necessity for prospective multicenter studies focusing on the prognostic role of cardiac magnetic resonance and electrophysiologic studies and on the therapeutic efficacy of targeted catheter ablation and mitral valve surgery in reducing the risk of life-threatening arrhythmias, as well as the role of implantable cardioverter defibrillators for primary prevention.
Reducing Hypermuscularization of the Transitional Segment Between Arterioles and Capillaries Protects Against Spontaneous Intracerebral Hemorrhage
Authors: Ratelade Julien , Klug Nicholas R. , Lombardi Damiano , Angelim Monara Kaelle Servulo Cruz , Dabertrand Fabrice , Domenga-Denier Valérie , Salman Rustam Al-Shahi , Smith Colin , Gerbeau Jean-Frédéric , Nelson Mark T. , Joutel Anne
Published: March 2020

Background:

Spontaneous deep intracerebral hemorrhage (ICH) is a devastating subtype of stroke without specific treatments. It has been thought that smooth muscle cell (SMC) degeneration at the site of arteriolar wall rupture may be sufficient to cause hemorrhage. However, deep ICHs are rare in some aggressive small vessel diseases that are characterized by significant arteriolar SMC degeneration. Here we hypothesized that a second cellular defect may be required for the occurrence of ICH.

Methods:

We studied a genetic model of spontaneous deep ICH using
Col4a1

+/G498V

and
Col4a1

+/G1064D

mouse lines that are mutated for the α1 chain of collagen type IV. We analyzed cerebroretinal microvessels, performed genetic rescue experiments, vascular reactivity analysis, and computational modeling. We examined postmortem brain tissues from patients with sporadic deep ICH.

Results:

We identified in the normal cerebroretinal vasculature a novel segment between arterioles and capillaries, herein called the transitional segment (TS), which is covered by mural cells distinct from SMCs and pericytes. In
Col4a1
mutant mice, this TS was hypermuscularized, with a hyperplasia of mural cells expressing more contractile proteins, whereas the upstream arteriole exhibited a loss of SMCs. TSs mechanistically showed a transient increase in proliferation of mural cells during postnatal maturation. Mutant brain microvessels, unlike mutant arteries, displayed a significant upregulation of SM genes and
Notch3
target genes, and genetic reduction of
Notch3
in
Col4a1

+/G498V

mice protected against ICH. Retina analysis showed that hypermuscularization of the TS was attenuated, but arteriolar SMC loss was unchanged in
Col4a1

+/G498V

,
Notch3
+/−
mice. Moreover, hypermuscularization of the retinal TS increased its contractility and tone and raised the intravascular pressure in the upstream feeding arteriole. We similarly found hypermuscularization of the TS and focal arteriolar SMC loss in brain tissues from patients with sporadic deep ICH.

Conclusions:

Our results suggest that hypermuscularization of the TS, through increased Notch3 activity, is involved in the occurrence of ICH in
Col4a1
mutant mice, by raising the intravascular pressure in the upstream feeding arteriole and promoting its rupture at the site of SMC loss. Our human data indicate that these 2 mutually reinforcing vascular defects may represent a general mechanism of deep ICH.
Myocardial Energetics in Obesity
Authors: Rayner Jennifer J. , Peterzan Mark A. , Watson William D. , Clarke William T. , Neubauer Stefan , Rodgers Christopher T. , Rider Oliver J.
Published: March 2020

Background:

Obesity is strongly associated with exercise intolerance and the development of heart failure. Whereas myocardial energetics and diastolic function are impaired in obesity, systolic function is usually preserved. This suggests that the rate of ATP delivery is maintained, but this has never been explored in human obesity. We hypothesized that ATP transfer rate through creatine kinase (CK) (
k
f
CKrest
) would be increased, compensating for depleted energy stores (phosphocreatine/ATP), but potentially limiting greater ATP delivery during increased workload. We hypothesized that these changes would normalize with weight loss.

Methods:

We recruited 80 volunteers (35 controls [body mass index 24±3 kg/m
2
], 45 obese [body mass index 35±5 kg/m
2
]) without coexisting cardiovascular disease. Participants underwent body composition analysis, magnetic resonance imaging of abdominal, liver, and myocardial fat content, left ventricular function, and
31
P magnetic resonance spectroscopy to assess phosphocreatine/ATP and CK kinetics, at rest and during dobutamine stress. Obese volunteers were assigned to a dietary weight loss intervention, before reexamination.

Results:

At rest, although myocardial phosphocreatine/ATP was 14% lower in obesity (1.9±0.3 versus 2.2±0.2,
P
<0.001),
k
f
Ckrest
was 33% higher (0.23±0.07 s
–1
versus 0.16±0.08 s
–1
,
P
=0.002), yielding no difference in overall resting ATP delivery (obese 2.5±0.9 µmol·g
–1
·s
–1
versus control 2.2±1.1 µmol·g
–1
·s
–1
,
P
=0.232). In controls, increasing cardiac workload led to an increase in both
k
f
CK
(+86%,
P
<0.001) and ATP delivery (+80%,
P
<0.001). However, in obesity, similar stress led to no significant increase in either
k
f
CK
(
P
=0.117) or ATP delivery (
P
=0.608). This was accompanied by reduced systolic augmentation (absolute increase in left ventricular ejection fraction, obese +16±7% versus control +21±4%,
P
=0.031). Successful weight loss (–11±5% body weight) was associated with improvement of these energetic changes such that there was no significant difference in comparison with controls.

Conclusions:

In the obese resting heart, the myocardial CK reaction rate is increased, maintaining ATP delivery despite reduced phosphocreatine/ATP. During increased workload, although the nonobese heart increases ATP delivery through CK, the obese heart does not; this is associated with reduced systolic augmentation and exercise tolerance. Weight loss reverses these energetic changes. This highlights myocardial energy delivery through CK as a potential therapeutic target to improve symptoms in obesity-related heart disease, and a fascinating modifiable pathway involved in the progression to heart failure, as well.
Secretome Analysis of Cardiomyocytes Identifies PCSK6 (Proprotein Convertase Subtilisin/Kexin Type 6) as a Novel Player in Cardiac Remodeling After Myocardial Infarction
Authors: Kuhn Tim Christian , Knobel Johannes , Burkert-Rettenmaier Sonja , Li Xue , Meyer Ingmar Sören , Jungmann Andreas , Sicklinger Florian , Backs Johannes , Lasitschka Felix , Müller Oliver J. , Katus Hugo A. , Krijgsveld Jeroen , Leuschner Florian
Published: March 2020

Background:

Acute occlusion of a coronary artery results in swift tissue necrosis. Bordering areas of the infarcted myocardium can also experience impaired blood supply and reduced oxygen delivery, leading to altered metabolic and mechanical processes. Although transcriptional changes in hypoxic cardiomyocytes are well studied, little is known about the proteins that are actively secreted from these cells.

Methods:

We established a novel secretome analysis of cardiomyocytes by combining stable isotope labeling and click chemistry with subsequent mass spectrometry analysis. Further functional validation experiments included ELISA measurement of human samples, murine left anterior descending coronary artery ligation, and adeno-associated virus 9–mediated in vivo overexpression in mice.

Results:

The presented approach is feasible for analysis of the secretome of primary cardiomyocytes without serum starvation. A total of 1026 proteins were identified to be secreted within 24 hours, indicating a 5-fold increase in detection compared with former approaches. Among them, a variety of proteins have not yet been explored in the context of cardiovascular pathologies. One of the secreted factors most strongly upregulated upon hypoxia was PCSK6 (proprotein convertase subtilisin/kexin type 6). Validation experiments revealed an increase of PCSK6 on mRNA and protein level in hypoxic cardiomyocytes. PCSK6 expression was elevated in hearts of mice after 3 days of ligation of the left anterior descending artery, a finding confirmed by immunohistochemistry. ELISA measurements in human serum also indicate distinct kinetics for PCSK6 in patients with acute myocardial infarction, with a peak on postinfarction day 3. Transfer of PCSK6-depleted cardiomyocyte secretome resulted in decreased expression of collagen I and III in fibroblasts compared with control treated cells, and small interfering RNA–mediated knockdown of PCSK6 in cardiomyocytes impacted transforming growth factor-β activation and SMAD3 (mothers against decapentaplegic homolog 3) translocation in fibroblasts. An adeno-associated virus 9–mediated, cardiomyocyte-specific overexpression of PCSK6 in mice resulted in increased collagen expression and cardiac fibrosis, as well as decreased left ventricular function, after myocardial infarction.

Conclusions:

A novel mass spectrometry–based approach allows investigation of the secretome of primary cardiomyocytes. Analysis of hypoxia-induced secretion led to the identification of PCSK6 as being crucially involved in cardiac remodeling after acute myocardial infarction.
White Blood Cells and Blood Pressure
Authors: Siedlinski Mateusz , Jozefczuk Ewelina , Xu Xiaoguang , Teumer Alexander , Evangelou Evangelos , Schnabel Renate B. , Welsh Paul , Maffia Pasquale , Erdmann Jeanette , Tomaszewski Maciej , Caulfield Mark J. , Sattar Naveed , Holmes Michael V. , Guzik Tomasz J.
Published: March 2020

Background:

High blood pressure (BP) is a risk factor for cardiovascular morbidity and mortality. While BP is regulated by the function of kidney, vasculature, and sympathetic nervous system, recent experimental data suggest that immune cells may play a role in hypertension.

Methods:

We studied the relationship between major white blood cell types and blood pressure in the UK Biobank population and used Mendelian randomization (MR) analyses using the ≈750 000 UK-Biobank/International Consortium of Blood Pressure-Genome-Wide Association Studies to examine which leukocyte populations may be causally linked to BP.

Results:

A positive association between quintiles of lymphocyte, monocyte, and neutrophil counts, and increased systolic BP, diastolic BP, and pulse pressure was observed (eg, adjusted systolic BP mean±SE for 1st versus 5th quintile respectively: 140.13±0.08 versus 141.62±0.07 mm Hg for lymphocyte, 139.51±0.08 versus 141.84±0.07 mm Hg for monocyte, and 137.96±0.08 versus 142.71±0.07 mm Hg for neutrophil counts; all
P
<10
–50
). Using 121 single nucleotide polymorphisms in MR, implemented through the inverse-variance weighted approach, we identified a potential causal relationship of lymphocyte count with systolic BP and diastolic BP (causal estimates: 0.69 [95% CI, 0.19–1.20] and 0.56 [95% CI, 0.23–0.90] of mm Hg per 1 SD genetically elevated lymphocyte count, respectively), which was directionally concordant to the observational findings. These inverse-variance weighted estimates were consistent with other robust MR methods. The exclusion of rs3184504 SNP in the
SH2B3
locus attenuated the magnitude of the signal in some of the MR analyses. MR in the reverse direction found evidence of positive effects of BP indices on counts of monocytes, neutrophils, and eosinophils but not lymphocytes or basophils. Subsequent MR testing of lymphocyte count in the context of genetic correlation with renal function or resting and postexercise heart rate demonstrated a positive association of lymphocyte count with urine albumin-to-creatinine ratio.

Conclusions:

Observational and genetic analyses demonstrate a concordant, positive and potentially causal relationship of lymphocyte count with systolic BP and diastolic BP.
Value of a Machine Learning Approach for Predicting Clinical Outcomes in Young Patients With Hypertension
Authors: Wu Xueyi , Yuan Xinglong , Wang Wei , Liu Kai , Qin Ying , Sun Xiaolu , Ma Wenjun , Zou Yubao , Zhang Huimin , Zhou Xianliang , Wu Haiying , Jiang Xiongjing , Cai Jun , Chang Wenbing , Zhou Shenghan , Song Lei
Published: March 2020

Risk stratification of young patients with hypertension remains challenging. Generally, machine learning (ML) is considered a promising alternative to traditional methods for clinical predictions because it is capable of processing large amounts of complex data. We, therefore, explored the feasibility of an ML approach for predicting outcomes in young patients with hypertension and compared its performance with that of approaches now commonly used in clinical practice. Baseline clinical data and a composite end point—comprising all-cause death, acute myocardial infarction, coronary artery revascularization, new-onset heart failure, new-onset atrial fibrillation/atrial flutter, sustained ventricular tachycardia/ventricular fibrillation, peripheral artery revascularization, new-onset stroke, end-stage renal disease—were evaluated in 508 young patients with hypertension (30.83±6.17 years) who had been treated at a tertiary hospital. Construction of the ML model, which consisted of recursive feature elimination, extreme gradient boosting, and 10-fold cross-validation, was performed at the 33-month follow-up evaluation, and the model’s performance was compared with that of the Cox regression and recalibrated Framingham Risk Score models. An 11-variable combination was considered most valuable for predicting outcomes using the ML approach. The C statistic for identifying patients with composite end points was 0.757 (95% CI, 0.660–0.854) for the ML model, whereas for Cox regression model and the recalibrated Framingham Risk Score model it was 0.723 (95% CI, 0.636–0.810) and 0.529 (95% CI, 0.403–0.655). The ML approach was comparable with Cox regression for determining the clinical prognosis of young patients with hypertension and was better than that of the recalibrated Framingham Risk Score model.