Correlation of serum VEGF-C, ANGPTL4, and activin A levels with frailty.

BACKGROUND: Secretory factors linked to lymphogenesis, such as vascular endothelial growth factor C (VEGF-C), angiopoietin like protein 4 (ANGPTL4), and activin A (ACV-A), have been recognized as potential markers of chronic inflammatory status and age-related diseases. Furthermore, these factors may also be linked to frailty. The primary objective of this study was to examine the serum VEGF-C, ANGPTL4, and ACV-A levels in young individuals, healthy older individuals, and older individuals with pre-frailty and frailty, and to determine their association with pro-inflammatory factor levels. METHODS: We conducted an observational study, enrolling a total of 210 older individuals and 20 young healthy volunteers. Participants were divided into four groups based on the Freid frailty phenotype: healthy young group, older patients without frailty group, pre-frail older group, and frail older group. Plasma and peripheral blood mononuclear cells (PBMCs) were collected from all four groups. ELISA was used to measure the serum levels of VEGF-C, ANGPTL4, ACV-A, and pro-inflammatory cytokines, while RT-qPCR was used to measure the transcription level of VEGF-C, ANGPTL4 and ACV-A in PBMCs. RESULTS: In comparison to healthy young individuals and older participants without frailty, older participants with frailty exhibited lower renal function, higher serum levels and transcription levels of VEGF-C, ANGPTL4, ACV-A, and elevated levels of pro-inflammatory cytokines (CRP, IL-1ß, and TNF-α). Multiple linear regression analysis revealed that serum levels of VEGF-C, ANGPTL4, and ACV-A were positively correlated with the frailty index, independent of age, eGFR, and comorbidities. Furthermore, the receiver operating characteristic (ROC) curve analysis demonstrated that serum levels of VEGF-C, ANGPTL4, and ACV-A have great accuracy in predicting frailty. CONCLUSION: Elevated serum levels of VEGF-C, ANGPTL4, and ACV-A are associated with frailty status.

Gegen Qinlian Decoction treatment of asymptomatic hyperuricemia by targeting circadian immune function.

BACKGROUND: The Gegen Qinlian Decoction (GGQLD) is a renowned traditional Chinese medicinal formula that has been used for centuries to effectively treat asymptomatic Hyperuricemia (HUA). This study aims to investigate the underlying mechanism of GGQLD's therapeutic effects on HUA. METHODS: The study enrolled a total of 25 healthy participants and 32 middle-aged and elderly individuals with asymptomatic HUA. All asymptomatic HUA participants were treated with GGQLD. Venous blood samples were collected from all participants to isolate peripheral blood mononuclear cells (PBMCs), which were then analyzed for biological profiles using flow cytometry. Network pharmacology analysis was utilized to identify the potential pathways involved in the therapeutic effects of GGQLD. Transcriptomic patterns of cultured proximal tubule epithelial cells (PTECs) were evaluated via bulk RNA-seq, and critical differentially expressed genes (DEGs) were identified and verified through ELISA. Molecular docking and molecular dynamics (MD) simulation were employed to investigate the potential compounds in GGQLD that may be involved in treating HUA. RESULTS: Network pharmacology analysis revealed that immune-related pathways might be involved in the therapeutic mechanism of GGQLD. RNA-seq analysis confirmed the involvement of innate lymphoid cell (ILC) development-related genes and clock genes. Polychromatic flow cytometric analysis demonstrated that GGQLD treatment reduced the proportion of ILC3s in total ILCs in asymptomatic HUA patients. ELISA results showed that GGQLD treatment reduced the levels of activating factors, such as ILC3-IL-18 and IL-1ß, in the plasma of HUA patients. GGQLD was also found to regulate circadian clock gene expression in PBMCs to treat asymptomatic HUA. Furthermore, the interaction between 40 compounds in GGQLD and HDAC3 (Histone Deacetylase 3), NLRP3 (NOD-like receptor protein 3), RORA (RAR-related orphan receptor A), and REV-ERBα (nuclear receptor subfamily 1) revealed that GGQLD may regulate ILCs and clock genes to treat asymptomatic HUA. CONCLUSIONS: The regulation of circadian clock gene expression and the proportion of ILC cells may be involved in the therapeutic effects of GGQLD on asymptomatic HUA patients.

Improved Renal Denervation Mitigated Hypertension Induced by Angiotensin II Infusion.

The benefits of renal sympathetic denervation (RDN) on blood pressure have been proved in a large number of clinical trials in recent years. However, the regulatory mechanism of RDN on hypertension remains elusive. Thus, it's essential to establish a simpler RDN model in mice. In this study, osmotic mini pumps filled with Angiotensin II were implanted in 14-week-old C57BL/6 mice. One week after the implantation of the mini-osmotic pump, a modified RDN procedure was performed on bilateral renal arteries of the mice using phenol. Age-sex-matched mice were given saline and served as sham group. Blood pressure was measured at baseline and every week subsequently for 21 days. Then, renal artery, abdominal aorta and heart were collected for histological examination using H&E and Masson staining. In this study, we present a simple, practical, repeatable, and standardized RDN model, which can control hypertension and alleviate cardiac hypertrophy. The technique can denervate peripheral renal sympathetic nerves without renal artery damage. Compared to previous models, the modified RDN facilitates the study of the pathobiology and pathophysiology of hypertension.

Ascending aortic perivascular adipose tissue inflammation associates with aortic valve disease.

BACKGROUND: Ascending aortic perivascular adipose tissue (AA-PVAT) mainly comprises brown adipose tissue (BAT), originates from neural crest cells that derive from ectoderm, and plays important role in angiotensin II-induced vascular inflammation and remodeling in mice. However, the characterization and function of human AA-PVAT remains highly unclear. METHODS: Patients with coronary artery disease (CAD) (n = 20) and aortic valve disease (AVD) (n = 23) who underwent cardiac surgery consented to take part in transcriptome and histological studies. Paired samples of AA-PVAT, epicardial adipose tissue (EAT), and subcutaneous adipose tissue (SAT) were obtained. RNA sequencing, histological analysis, quantitative reverse transcription polymerase chain reaction and western blot studies were performed on those samples. RESULTS: Human AA-PVAT exhibited smaller adipocyte morphology and high expression of brown adipocyte marker. Transcriptome analysis revealed that AA-PVAT showed unique transcriptome characteristics compared with EAT and SAT. While comparing CAD and AVD patients, AA-PVAT exhibited a decreasing brown phenotype and higher inflammatory response in AVD patients. Gene ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway analysis suggested that the differentially expressed genes in AA-PVAT between CAD and AVD patients were involved mainly in the processes of inflammation and metabolism regulation. CONCLUSIONS: Human AA-PVAT is a BAT-like adipose tissue with unique transcriptome characteristics, and exhibits a weakened brown phenotype and an enhanced inflammation response in AVD patients.

High Level of Serum Uric Acid induced Monocyte Inflammation is Related to Coronary Calcium Deposition in the Middle-Aged and Elder Population of China: A five-year Prospective Cohort Study.

Background: Serum uric acid (SUA) is suspected to be associated with atherosclerosis and calcium deposition in atherosclerosis is known to related poor prognosis, yet there is no cohort study on the aged in China. We aimed to investigate the relationships between SUA levels and coronary calcium deposition in the middle-aged and elderly populations in China. Methods: A total of 326 participants between the ages of 50 and 85 who had undergone a coronary CT scan in 2015 at the Huadong Hospital Affiliated to Fudan University (Shanghai, China) were included in this study. Univariate and multivariate binary logistic regression was performed to analyze the correlation between SUA levels and coronary artery calcium score (CACS). The changes in CACS during a five-year follow-up were analyzed through Kaplan-Meier survival and binary cox regression analysis. An observational study was done on another 104 asymptomatic middle-aged and elderly patients to compare relative mRNA expressions of proinflammatory factors in peripheral blood mononuclear cells (PBMCs) from 104 subjects. Results: Based on the first year of follow-up data analysis, the elevation of SUA levels (P<0.001) is an independent risk factor for the increase of CACS after coordinating the confounding factors. According to five-year follow-up data, cox regression analysis proved that SUA was a risk factor for CACS (HR =5.86, P<0.001). The mRNA expression of IL-6 and CXCL8 in the HUA and HUA patients with CAC (HUA-CAC) groups was significantly higher than that in the normal control (NC) and coronary calcium deposition (CAC) groups. Conclusion: Taken together, the findings in this study indicate that high SUA levels (P<0.001) are an independent risk factor for CACS and elevated SUA levels increase the risk of developing coronary calcium deposition among middle-aged and old people in the Chinese population, which may be related to an increase of pro-inflammatory cytokines in the PBMCs.

Association of Pericardiac Adipose Tissue With Coronary Artery Disease.

Background and Aim: Coronary artery disease (CAD) poses a worldwide health threat. Compelling evidence shows that pericardial adipose tissue (PAT), a brown-like adipose adjacent to the external surface of the pericardium, is associated with CAD. However, the specific molecular mechanisms of PAT in CAD are elusive. This study aims to characterize human PAT and explore its association with CAD. Methods: We acquired samples of PAT from 31 elective cardiac surgery patients (17 CAD patients and 14 controls). The transcriptome characteristics were assessed in 5 CAD patients and 4 controls via RNA-sequencing. Cluster profile R package, String database, Cytoscape were applied to analyze the potential pathways and PPI-network key to DEGS, whereas the hubgenes were predicted via Metascape, Cytohubba, and MCODE. We use Cibersort, ENCORI, and DGIDB to predict immunoinfiltration, mRNA-miRNA target gene network, and search potential drugs targeting key DEGs. The predictable hubgenes and infiltrating inflammatory cells were validated in 22 patients (12 CAD samples and 10 control samples) through RT-qPCR and immunohistochemistry. Results: A total of 147 different genes (104 up-regulated genes and 43 down-regulated genes) were identified in CAD patients. These different genes were associated with immunity and inflammatory dysfunction. Cibersort analysis showed monocytes and macrophages were the most common subsets in immune cells, whereas immunohistochemical results revealed there were more macrophages and higher proportion of M1 subtype cells in PAT of CAD patients. The PPI network and module analysis uncovered several crucial genes, defined as candidate genes, including Jun, ATF3, CXCR4, FOSB, CCl4, which were validated through RT-qPCR. The miRNA-mRNA network implicated hsa-miR-185-5p as diagnostic targets and drug-gene network showed colchicine, fenofibrate as potential therapeutic drugs, respectively. Conclusion: This study demonstrates that PAT is mainly associated with the occurrence of CAD following the dysfunction of immune and inflammatory processes. The identified hubgenes, predicted drugs and miRNAs are promising biomarkers and therapeutic targets for CAD.

Gegen Qinlian Decoction Ameliorates Hyperuricemia-Induced Renal Tubular Injury via Blocking the Inflammatory Signaling Pathway.

Background: Gegen Qinlian decoction (GGQLD) is a typical traditional Chinese medicine (TCM) prescription documented in Shang Han Lun. Clinically, GGQLD has been utilized to manage the inflammatory symptoms of metabolic diseases and to protect against renal damage in China. In the present study, a hypothesis was proposed that the multi-target solution of GGQLD produced anti-inflammatory effects on ameliorating hyperuricemia (HUA). Methods: A total of 30 primary HUA patients receiving GGQLD treatment (two doses daily) for 4 weeks were selected. Then, differences in uric acid (UA) levels and expression of peripheral blood mononuclear cells (PBMCs) and urinary exosomes before and after treatment were analyzed. The therapeutic indexes for the active ingredients in GGQLD against HUA were confirmed through pharmacological subnetwork analysis. Besides, the HUA rat model was established through oral gavage of potassium oxonate and treated with oral GGQLD. In addition, proximal tubular epithelial cells (PTECs) were stimulated by UA and intervened with GGQLD for 48 h. Subsequently, RNA-seq, flow cytometry, and confocal immunofluorescence microscopy were further conducted to characterize the differences in UA-mediated inflammation and apoptosis of human renal tubular epithelial cells pre- and post-administration of GGQLD. In the meanwhile, quantitative real-time PCR (qPCR) was carried out to determine gene expression, whereas a western blotting (WB) assay was conducted to measure protein expression. Results: Our network analysis revealed that GGQLD treated HUA via the anti-inflammatory and antiapoptotic pathways. Additionally, NLPR3 expression significantly decreased in PBMCs and urinary exosomes of HUA patients after GGQLD treatment. In vivo, GGQLD treatment alleviated HUA-induced renal inflammation, which was associated with decreased expression of NLRP3 inflammasomes and apoptosis-related mRNAs. Moreover, GGQLD promoted renal UA excretion by inhibiting the activation of GSDMD-dependent pyroptosis induced by NLRP3 inflammasomes and by reducing apoptosis via the mitochondrial apoptosis signaling pathway in vitro. Conclusion: This study indicates that GGQLD efficiently reduces inflammatory responses while promoting UA excretion in HUA. Our findings also provide compelling evidence supporting the idea that GGQLD protects against the UA-mediated renal tubular epithelial cell inflammation through the mitochondrial apoptosis signaling pathways. Taken together, these findings have demonstrated a novel therapeutic method for the treatment of HUA.

Reduced inflammatory responses to SARS-CoV-2 infection in children presenting to hospital with COVID-19 in China.

BACKGROUND: Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in children is associated with better outcomes than in adults. The inflammatory response to COVID-19 infection in children remains poorly characterised. METHODS: We retrospectively analysed the medical records of 127 laboratory-confirmed COVID-19 patients aged 1 month to 16 years from Wuhan and Jingzhou of Hubei Province. Patients presented between January 25th and March 24th 2020. Information on clinical features, laboratory results, plasma cytokines/chemokines and lymphocyte subsets were analysed. FINDINGS: Children admitted to hospital with COVID-19 were more likely to be male (67.7%) and the median age was 7.3 [IQR 4.9] years. All but one patient with severe disease was aged under 2 and the majority (5/7) had significant co-morbidities. Despite 53% having viral pneumonia on computed tomography (CT) scanning only 2 patients had low lymphocyte counts and no differences were observed in the levels of plasma proinflammatory cytokines, including interleukin (IL)-2, IL-4, IL-6, tumour necrosis factor (TNF)- α , and interferon (IFN)- γ between patients with mild, moderate or severe disease. INTERPRETATIONS: We observed that the immune responses of children to COVID-19 infection is significantly different from that seen in adults. Our evidence suggests that SARS-CoV-2 does not trigger a robust inflammatory response or 'cytokine storm' in children with COVID-19, and this may underlie the generally better outcomes seen in children with this disease.

The Role of Sorting Nexin 17 in Cardiac Development.

Sorting nexin 17 (SNX17), a member of sorting nexin (SNX) family, acts as a modulator for endocytic recycling of membrane proteins. Results from our previous study demonstrated the embryonic lethality of homozygous defect of SNX17. In this study, we investigated the role of SNX17 in rat fetal development. Specifically, we analyzed patterns of SNX17 messenger RNA (mRNA) expression in multiple rat tissues and found high expression in the cardiac outflow tract (OFT). This expression was gradually elevated during the cardiac OFT morphogenesis. Homozygous deletion of the SNX17 gene in rats resulted in mid-gestational embryonic lethality, which was accompanied by congenital heart defects, including the double-outlet right ventricle and atrioventricular and ventricular septal defects, whereas heterozygotes exhibited normal fetal development. Moreover, we found normal migration distance and the number of cardiac neural crest cells during the OFT morphogenesis. Although cellular proliferation in the cardiac OFT endocardial cushion was not affected, cellular apoptosis was significantly suppressed. Transcriptomic profiles and quantitative real-time PCR data in the cardiac OFT showed that SNX17 deletion resulted in abnormal expression of genes associated with cardiac development. Overall, these findings suggest that SNX17 plays a crucial role in cardiac development.

Disorders of sodium balance and its clinical implications in COVID-19 patients: a multicenter retrospective study.

BACKGROUND: The worldwide spread of SARS-CoV-2 has infected millions of people leading to over 0.3 million mortalities. The disruption of sodium homeostasis, tends to be a common occurrence in patients with COVID-19. METHODS AND RESULTS: A total of 1,254 COVID-19 patients comprising 124 (9.9%) hyponatremic patients (under 135 mmol/L) and 30 (2.4%) hypernatremic patients (over 145 mmol/L) from three hospitals in Hubei, China, were enrolled in the study. The relationships between sodium balance disorders in COVID-19 patients, its clinical features, implications, and the underlying causes were presented. Hyponatremia patients were observed to be elderly, had more comorbidities, with severe pneumonic chest radiographic findings. They were also more likely to have a fever, nausea, higher leukocyte and neutrophils count, and a high sensitivity C-reactive protein (HS-CRP). Compared to normonatremia patients, renal insufficiency was common in both hyponatremia and hypernatremia patients. In addition, hyponatremia patients required extensive treatment with oxygen, antibiotics, and corticosteroids. The only significant differences between the hypernatremia and normonatremia patients were laboratory findings and clinical complications, and patients with hypernatremia were more likely to use traditional Chinese medicine for treatment compared to normonatremia patients. This study indicates that severity of the disease, the length of stay in the hospital of surviving patients, and mortality were higher among COVID-19 patients with sodium balance disorders. CONCLUSION: Sodium balance disorder, particularly hyponatremia, is a common condition among hospitalized patients with COVID-19 in Hubei, China, and it is associated with a higher risk of severe illness and increased in-hospital mortality.

NAD+ administration decreases microvascular damage following cardiac ischemia/reperfusion by restoring autophagic flux.

Microvascular damage is a key pathological change in myocardial ischemia/reperfusion (I/R) injury. Using a rat model of myocardial I/R, our current study has provided the first evidence that nicotinamide adenine dinucleotide (NAD+) administration can significantly attenuate myocardial I/R-induced microvascular damage, including reduced regional blood perfusion, decreased microvessel density and integrity, and coronary microvascular endothelial cells (CMECs) injury. In studies with primary cultured CMECs under hypoxia/reoxygenation (HR) and a rat model of I/R, our results suggested that the protective effect of NAD+ on CMECs exposed to HR or I/R is at least partially mediated by the NAD+-induced restoration of autophagic flux, especially lysosomal autophagy: NAD+ treatment markedly induced transcription factor EB (TFEB) activation and attenuated lysosomal dysfunction in the I/R or HR-exposed cells. Collectively, our study has provided the first in vivo and in vitro evidence that NAD+ significantly rescued the impaired autophagic flux and cell apoptosis that was induced by I/R in rat CMECs, which is mediated in part through the action of TFEB-mediated lysosomal autophagy.

Aging-induced IL27Ra signaling impairs hematopoietic stem cells.

Hematopoietic stem cell (HSC) aging correlates with an increasing risk of myeloproliferative disease and immunosenescence. In this study, we show that aging-related inflammation promotes HSC aging through tumor necrosis factor-α (TNF-α)→ERK→ETS1→interleukin27Ra (IL27Ra) pathway. TNF-α, a well-known biomarker of inflammation, increases during aging and induces the expression of IL27Ra on HSCs via ERK-ETS1 signaling. Deletion of IL27Ra rescues the functional decline and myeloid bias of HSCs and also reverses the inhibitory effect of TNF-α on HSCs. Aged IL27Ra-/- mice had a reduced proportion of myeloid-biased HSCs and did not display the biased myeloid differentiation that occurs in aged wild-type mice. IL27Ra+ HSCs exhibit impaired reconstitution capacity and myeloid-bias compared with IL27Ra- HSCs and serve as a myeloid-recovery pool upon inflammatory insult. Inflammation-related genes were enriched in IL27Ra+ HSCs and this enrichment increases with aging. Our study demonstrates that age-induced IL27Ra signaling impairs HSCs and raises the possibility that interfering with IL27Ra signaling can counter the physiologically deleterious effect of aging on hematopoietic capacity.

Isolation, Culture, and Adipogenic Induction of Neural Crest Original Adipose-Derived Stem Cells from Periaortic Adipose Tissue.

An excessive amount of adipose tissue surrounding the blood vessels (perivascular adipose tissue, also known as PVAT) is associated with a high risk of cardiovascular disease. ADSCs derived from different adipose tissues show distinct features, and those from the PVAT have not been well characterized. In a recent study, we reported that some ADSCs in the periaortic arch adipose tissue (PAAT) descend from the neural crest cells (NCCs), a transient population of migratory cells originating from the ectoderm. In this paper, we describe a protocol for isolating red fluorescent protein (RFP)-labeled NCCs from the PAAT of Wnt-1 Cre+/-;Rosa26RFP/+ mice and inducing their adipogenic differentiation in vitro. Briefly, the stromal vascular fraction (SVF) is enzymatically dissociated from the PAAT, and the RFP+ neural crest derived ADSCs (NCADSCs) are isolated by fluorescence activated cell sorting (FACS). The NCADSCs differentiate into both brown and white adipocytes, can be cryopreserved, and retain their adipogenic potential for ~3-5 passages. Our protocol can generate abundant ADSCs from the PVAT for modeling PVAT adipogenesis or lipogenesis in vitro. Thus, these NCADSCs can provide a valuable system for studying the molecular switches involved in PVAT differentiation.

Adventitial fibroblast-derived vascular endothelial growth factor promotes vasa vasorum-associated neointima formation and macrophage recruitment.

AIMS: Adventitial vasa vasorum provides oxygen and nourishment to the vascular wall, but whether it regulates vascular disease remains unclear. We have previously shown that an increased expression of VEGF (vascular endothelial growth factor) is associated with macrophage infiltration. This study aims to determine whether adventitial fibroblast (AF)-derived VEGF increases the number of vasa vasorum contributing to neointima formation through macrophage recruitment. METHODS AND RESULTS: In rat balloon injury model, vasa vasorum count was increased particularly in the adventitia accompanied by cell proliferation and VEGF expression. Both endogenous and PKH26-labelled exogenous macrophages were mainly distributed in adventitia around vasa vasorum. Interestingly, perivascular delivery of Ranibizumab preferentially concentrated in adventitia resulted in a decrease of neointima formation with concurrent reduction of vasa vasorum count and macrophage infiltration. AFs with adenovirus-mediated VEGF over-expression delivered to the adventitia significantly enhanced these pathological changes after injury. In Tie2-cre/Rosa-LoxP-RFP mice, endothelial cells were increased in the adventitia after wire injury. By using multiphoton laser scanning microscopy, macrophage rolling, adhesion and transmigration were observed in vasa vasorum. Moreover, adoptive transfer of macrophages accelerated injury-induced neointima formation. VEGF-neutralizing antibody administration also attenuated wire injury-induced neointima formation and macrophage infiltration. In primary cultured AFs, exogenous VEGF increased VEGF expression and secretion in a time- and dose-dependent manner. AF-conditioned medium promoted endothelial cell angiogenesis, vascular cell adhesion molecule-1 expression and macrophage adhesion was blocked by VEGF-neutralizing antibody and VEGFR2 inhibitor ZM323881, which also inhibited activation of VEGFR2/ERK1/2 pathway. CONCLUSION: These results demonstrate that AF-derived VEGF plays a significant role in the increase of vasa vasorum count which is involved in macrophage recruitment and neointima formation.

The Schizophrenia Susceptibility Gene OPCML Regulates Spine Maturation and Cognitive Behaviors through Eph-Cofilin Signaling.

Previous genetic and biological evidence converge on the involvement of synaptic dysfunction in schizophrenia, and OPCML, encoding a synaptic membrane protein, is reported to be genetically associated with schizophrenia. However, its role in the pathophysiology of schizophrenia remains largely unknown. Here, we found that Opcml is strongly expressed in the mouse hippocampus; ablation of Opcml leads to reduced phosphorylated cofilin and dysregulated F-actin dynamics, which disturbs the spine maturation. Furthermore, Opcml interacts with EphB2 to control the stability of spines by regulating the ephrin-EphB2-cofilin signaling pathway. Opcml-deficient mice display impaired cognitive behaviors and abnormal sensorimotor gating, which are similar to features in neuropsychiatric disorders such as schizophrenia. Notably, the administration of aripiprazole partially restores the abnormal behaviors in Opcml-/- mice by increasing the phosphorylated cofilin level and facilitating spine maturation. We demonstrated a critical role of the schizophrenia-susceptible gene OPCML in spine maturation and cognitive behaviors via regulating the ephrin-EphB2-cofilin signaling pathway, providing further insights into the characteristics of schizophrenia.

Limited Regeneration Potential with Minimal Epicardial Progenitor Conversions in the Neonatal Mouse Heart after Injury.

The regeneration capacity of neonatal mouse heart is controversial. In addition, whether epicardial cells provide a progenitor pool for de novo heart regeneration is incompletely defined. Following apical resection of the neonatal mouse heart, we observed limited regeneration potential. Fate-mapping of Tbx18MerCreMer mice revealed that newly formed coronary vessels and a limited number of cardiomyocytes were derived from the T-box transcription factor 18 (Tbx18) lineage. However, further lineage tracing with SM-MHCCreERT2 and Nfactc1Cre mice revealed that the new smooth muscle and endothelial cells are in fact derivatives of pre-existing coronary vessels. Our data show that neonatal mouse heart can regenerate but that its potential is limited. Moreover, although epicardial cells are multipotent during embryogenesis, their contribution to heart repair through "stem" or "progenitor" cell conversion is minimal after birth. These observations suggest that early embryonic heart development and postnatal heart regeneration are distinct biological processes. Multipotency of epicardial cells is significantly decreased after birth.

Neural Crest Cells Differentiate Into Brown Adipocytes and Contribute to Periaortic Arch Adipose Tissue Formation.

OBJECTIVE: Periaortic arch adipose tissue (PAAT) plays critical roles in regulating vascular homeostasis; however, its anatomic features, developmental processes, and origins remain unclear. Approach and Results: Anatomic analysis and genetic lineage tracing of Wnt1 (wingless-type MMTV [mouse mammary tumor virus] integration site family member 1)-Cre+;Rosa26RFP/+ mice, Myf5 (myogenic factor 5)-Cre+;Rosa26RFP/+ mice, and SM22α-Cre+;Rosa26RFP/+ mice are performed, and the results show that PAAT has unique anatomic features, and the developmental processes of PAAT are independent of the others periaortic adipose tissues. PAAT adipocytes are mainly derived from neural crest cells (NCCs) rather than from Myf5+ progenitors. Most PAAT adipocyte progenitors expressed SM22α+ (smooth muscle protein 22-alpha) during development. Using Wnt1-Cre+;PPARγflox/flox mice, we found that knockout of PPAR (peroxisome proliferator-activated receptor)-γ in NCCs results in PAAT developmental delay and dysplasia, further confirming that NCCs contribute to PAAT formation. And we further indicated PAAT dysplasia aggravates Ang II (angiotensin II)-induced inflammation and remodeling of the common carotid artery close to aorta arch. We also found that NCCs can be differentiated into both brown and white adipocytes in vivo and in vitro. RNA sequencing results suggested NCC-derived adipose tissue displays a distinct transcriptional profile compared with the non-NCC-derived adipose tissue in PAAT. CONCLUSIONS: PAAT has distinctive anatomic features and developmental processes. Most PAAT adipocytes are originated from NCCs which derive from ectoderm. NCCs are progenitors not only of white adipocytes but also of brown adipocytes. This study indicates that the PAAT is derived from multiple cell lineages, the adipocytes derived from different origins have distinct transcriptional profiles, and PAAT plays a critical role in Ang II-induced common carotid artery inflammation and remodeling.Visual OvervieW: An online visual overview is available for this article.

Membrane raft redox signalling contributes to endothelial dysfunction and vascular remodelling of thoracic aorta in angiotensin II-infused rats.

NEW FINDINGS: What is the central question of this study? Is the membrane raft redox signalling pathway involved in blood pressure increase, endothelial dysfunction and vascular remodelling in an angiotensin II-induced hypertensive animal model? What is the main finding and its importance? The membrane raft redox signalling pathway was involved in endothelial dysfunction and medial remodelling in angiotensin II-induced hypertension. ABSTRACT: The membrane raft (MR) redox pathway is characterized by NADPH oxidase activation via the clustering of its subunits through lysosome fusion and the activation of acid sphingomyelinase (ASMase). Our previous study shows that the MR redox signalling pathway is associated with angiontensin II (AngII)-induced production of reactive oxygen species (ROS) and endothelial dysfunction in rat mesenteric arteries. In the present study, we hypothesized that this signalling pathway is involved in blood pressure increase, endothelial dysfunction and vascular remodelling in an AngII-induced hypertensive animal model. Sixteen-week-old male Sprague-Dawley rats were subjected to AngII infusion for 2 weeks with or without treatment with the lysosome fusion inhibitor bafilomycin A1 and ASMase inhibitor amitriptyline. After treatments, aortas were harvested for further study. The results showed that the MR redox signalling pathway was activated as indicated by the increase of MR formation, ASMase activity and ROS production in aorta from AngII-infused rats compared with that from control rats. MR formation and ROS production were significantly inhibited in thoracic aorta from AngII-induced rats treated with bafilomycin A1 and amitriptyline. Both treatments significantly attenuated blood pressure increase, endothelial dysfunction and vascular remodelling including medial hypertrophy, and increased collagen and fibronectin deposition in thoracic aortas from AngII-infused rats. Finally, both treatments significantly prevented the increase of inflammatory factors including monocyte chemotactic protein 1, intercellular adhesion molecule 1 and tumour necrosis factor α in thoracic aorta from AngII-infused rats. In conclusion, the present study demonstrates that the MR redox signalling pathway was involved in endothelial dysfunction and medial remodelling in AngII-induced hypertension.

Endothelial-specific deletion of Ets-1 attenuates Angiotensin II-induced cardiac fibrosis via suppression of endothelial-to-mesenchymal transition.

Cardiac fibrosis is a common feature in chronic hypertension patients with advanced heart failure, and endothelial-tomesenchymal transition (EndMT) is known to promote Angiotensin II (Ang II)-mediated cardiac fibrosis. Previous studies have suggested a potential role for the transcription factor, ETS-1, in Ang II-mediated cardiac remodeling, however the mechanism are not well defined. In this study, we found that mice with endothelial Ets-1 deletion showed reduced cardiac fibrosis and hypertrophy following Ang II infusion. The reduced cardiac fibrosis was accompanied by decreased expression of fibrotic matrix genes, reduced EndMT with decreased Snail, Slug, Twist, and ZEB1 expression, as well as reduced cardiac hypertrophy and expression of hypertrophyassociated genes was observed. In vitro studies using cultured H5V cells further confirmed that ETS-1 knockdown inhibited TGF-ß1-induced EndMT. This study revealed that deletion of endothelial Ets-1 attenuated Ang II-induced cardiac fibrosis via inhibition of EndMT, indicating an important ETS-1 function in mediating EndMT. Inhibition of ETS-1 could be a potential therapeutic strategy for treatment of heart failure secondary to chronic hypertension. [BMB Reports 2019; 52(10): 595-600].

Developmental and functional characteristics of the thoracic aorta perivascular adipocyte.

Thoracic aorta perivascular adipose tissue (T-PVAT) has critical roles in regulating vascular homeostasis. However, the developmental characteristics and cellular lineage of adipocyte in the T-PVAT remain unclear. We show that T-PVAT contains three long strip-shaped fat depots, anterior T-PVAT (A-T-PVAT), left lateral T-PVAT (LL-T-PVAT), and right lateral T-PVAT (RL-T-PVAT). A-T-PVAT displays a distinct transcriptional profile and developmental origin compared to the two lateral T-PVATs (L-T-PVAT). Lineage tracing studies indicate that A-T-PVAT adipocytes are primarily derived from SM22α+ progenitors, whereas L-T-PVAT contains both SM22α+ and Myf5+ cells. We also show that L-T-PVAT contains more UCP1+ brown adipocytes than A-T-PVAT, and L-T-PVAT exerts a greater relaxing effect on aorta than A-T-PVAT. Angiotensin II-infused hypertensive mice display greater macrophage infiltration into A-T-PVAT than L-T-PVAT. These combined results indicate that L-T-PVAT has a distinct development from A-T-PVAT with different cellular lineage, and suggest that L-T-PVAT and A-T-PVAT have different physiological and pathological functions.