Targeting PDE4B (Phosphodiesterase-4 Subtype B) for Cardioprotection in Acute Myocardial Infarction via Neutrophils and Microcirculation.

BACKGROUND: Timely and complete restoration of blood flow is the most effective intervention for patients with acute myocardial infarction. However, the efficacy is limited by myocardial ischemia-reperfusion (MI/R) injury. PDE4 (phosphodiesterase-4) hydrolyzes intracellular cyclic adenosine monophosphate and it has 4 subtypes A-D. This study aimed to delineate the role of PDE4B (phosphodiesterase-4 subtype B) in MI/R injury. METHODS: Mice were subjected to 30-minute coronary artery ligation, followed by 24-hour reperfusion. Cardiac perfusion was assessed by laser Doppler flow. Vasomotor reactivities were determined in mouse and human coronary (micro-)arteries. RESULTS: Cardiac expression of PDE4B, but not other PDE4 subtypes, was increased in mice following reperfusion. PDE4B was detected primarily in endothelial and myeloid cells of mouse and human hearts. PDE4B deletion strikingly reduced infarct size and improved cardiac function 24-hour or 28-day after MI/R. PDE4B in bone marrow-derived cells promoted MI/R injury and vascular PDE4B further exaggerated this injury. Mechanistically, PDE4B mediated neutrophil-endothelial cell interaction and PKA (protein kinase A)-dependent expression of cell adhesion molecules, neutrophil cardiac infiltration, and release of proinflammatory cytokines. Meanwhile, PDE4B promoted coronary microcirculatory obstruction and vascular permeability in MI/R, without affecting flow restriction-induced thrombosis. PDE4B blockade increased flow-mediated vasodilatation and promoted endothelium-dependent dilatation of coronary arteries in a PKA- and nitric oxide-dependent manner. Furthermore, postischemia administration with piclamilast, a PDE4 pan-inhibitor, improved cardiac microcirculation, suppressed inflammation, and attenuated MI/R injury in mice. Incubation with sera from patients with acute myocardial infarction impaired acetylcholine-induced relaxations in human coronary microarteries, which was abolished by PDE4 inhibition. Similar protection against MI/R-related coronary injury was recapitulated in mice with PDE4B deletion or inhibition, but not with the pure vasodilator, sodium nitroprusside. CONCLUSIONS: PDE4B is critically involved in neutrophil inflammation and microvascular obstruction, leading to MI/R injury. Selective inhibition of PDE4B might protect cardiac function in patients with acute myocardial infarction designated for reperfusion therapy.

Dysregulation of histone H3 lysine 27 trimethylation in transforming growth factor-ß1-induced gene expression in mesangial cells and diabetic kidney.

Transforming growth factor-ß1 (TGF-ß)-induced fibrotic and inflammatory genes in renal mesangial cells (MCs) play important roles in glomerular dysfunction associated with diabetic nephropathy (DN). TGF-ß regulates gene expression in MCs by altering key chromatin histone modifications at target gene promoters. However, the role of the repressive histone H3 lysine 27 trimethylation (H3K27me3) modification is unclear. Here we show that TGF-ß reduces H3K27me3 at the Ctgf, Serpine1, and Ccl2 gene promoters in rat MCs (RMCs) and reciprocally up-regulates the expression of these pro-fibrotic and inflammatory genes. In parallel, TGF-ß down-regulates Enhancer of Zeste homolog 2 (Ezh2), an H3K27me3 methyltransferase, and decreases its recruitment at Ctgf and Ccl2 but not Serpine1 promoters. Ezh2 knockdown with siRNAs enhances TGF-ß-induced expression of these genes, supporting its repressive function. Mechanistically, Ezh2 down-regulation is mediated by TGF-ß-induced microRNA, miR-101b, which targets Ezh2 3'-UTR. TGF-ß also up-regulates Jmjd3 and Utx in RMCs, suggesting a key role for these H3K27me3 demethylases in H3K27me3 inhibition. In RMCs, Utx knockdown inhibits hypertrophy, a key event in glomerular dysfunction. The H3K27me3 regulators are similarly altered in human and mouse MCs. High glucose inhibits Ezh2 and increases miR-101b in a TGF-ß-dependent manner. Furthermore, in kidneys from rodent models of DN, fibrotic genes, miR-101b, and H3K27me3 demethylases are up-regulated, whereas Ezh2 protein levels as well as enrichment of Ezh2 and H3K27me3 at target genes are decreased, demonstrating in vivo relevance. These results suggest that H3K27me3 inhibition by TGF-ß via dysregulation of related histone-modifying enzymes and miRNAs augments pathological genes mediating glomerular mesangial dysfunction and DN.

A Novel Angiotensin II-Induced Long Noncoding RNA Giver Regulates Oxidative Stress, Inflammation, and Proliferation in Vascular Smooth Muscle Cells.

RATIONALE: AngII (angiotensin II)-mediated vascular smooth muscle cell (VSMC) dysfunction plays a major role in hypertension. Long noncoding RNAs have elicited much interest, but their molecular roles in AngII actions and hypertension are unclear. OBJECTIVE: To investigate the regulation and functions of a novel long noncoding RNA growth factor- and proinflammatory cytokine-induced vascular cell-expressed RNA ( Giver), in AngII-mediated VSMC dysfunction. METHODS AND RESULTS: RNA-sequencing and real-time quantitative polymerase chain reactions revealed that treatment of rat VSMC with AngII increased the expression of Giver and Nr4a3, an adjacent gene encoding a nuclear receptor. Similar changes were observed in rat and mouse aortas treated ex vivo with AngII. RNA-FISH (fluorescence in situ hybridization) and subcellular fractionation showed predominantly nuclear localization of Giver. AngII increased Giver expression via recruitment of Nr4a3 to Giver promoter. Microarray profiling and real-time quantitative polymerase chain reaction validation in VSMC showed that Giver knockdown attenuated the expression of genes involved in oxidative stress ( Nox1) and inflammation ( Il6, Ccl2, Tnf) but increased Nr4a3. Conversely, endogenous Giver overexpression showed opposite effects supporting its role in oxidative stress and inflammation. Chromatin immunoprecipitation assays showed Giver overexpression also increased Pol II (RNA polymerase II) enrichment and decreased repressive histone modification histone H3 trimethylation on lysine 27 at Nox1 and inflammatory gene promoters. Accordingly, Giver knockdown inhibited AngII-induced oxidative stress and proliferation in rat VSMC. RNA-pulldown combined with mass spectrometry showed Giver interacts with nuclear and chromatin remodeling proteins and corepressors, including NONO (non-pou domain-containing octamer-binding protein). Moreover, NONO knockdown elicited similar effects as Giver knockdown on the expression of key Giver-regulated genes. Notably, GIVER and NR4A3 were increased in AngII-treated human VSMC and in arteries from hypertensive patients but attenuated in hypertensive patients treated with ACE (angiotensin-converting enzyme) inhibitors or angiotensin receptor blockers. Furthermore, human GIVER also exhibits partial functional conservation with rat Giver. CONCLUSIONS: Giver and its regulator Nr4a3 are important players in AngII-mediated VSMC dysfunction and could be novel targets for antihypertensive therapy.

Tumor Necrosis Factor-alpha (TNF-α) Enhances miR-155-Mediated Endothelial Senescence by Targeting Sirtuin1 (SIRT1).

BACKGROUND Sirtuin1 (SIRT1) participates in a wide variety of cellular processes, but the molecular mechanism remains largely unknown. miR-155 is an element of the inflammatory signaling pathway in atherosclerosis. Therefore, we tested the hypothesis that TNF-alpha stimulates miR-155 to target SIRT1 and thereby regulates endothelial senescence, and we also explored the function of miR-155 as a regulator of cardiovascular diseases. MATERIAL AND METHODS TNF-alpha was used to stimulate human umbilical vein endothelial cells (HUVECs), after which protein and gene expression were assessed via Western blotting and RT-qPCR. miR-155 targeting of SIRT1 was confirmed via luciferase reporter assays, while MTT and senescence-associated ß-galactosidase (SA-ß-gal) assays were used for quantifying cellular proliferation and senescence. RESULTS We found that miR-155 was upregulated in response to TNF-alpha treatment, in addition to inducing marked changes in SIRT1/FoxO-1/p21 pathway protein level. When we overexpressed miR-155 mimics, SIRT1 was markedly reduced, whereas miR-155 inhibition had the opposite effect in TNF-alpha-treated cells. We additionally confirmed that miR-155 was able to directly bind to SIRT1 3'-UTR, and that inhibition of miR-155 reduced the ability of TNF-alpha to induce senescence in HUVECs, thereby leading to their enhanced proliferation. Simvastatin was associated with suppression of miR-155 expression in HUVECs following TNF-alpha treatment, and with a corresponding reduction in TNF-alpha-induced senescence, whereas miR-155 overexpression had the opposite effect. CONCLUSIONS Our findings suggest that TNF-alpha upregulates miR-155, which then targets SIRT1, suppressing its expression and driving HUVEC apoptosis. Simvastatin disrupted this senescence mechanism via the miR-155/SIRT1/FoxO-1/p21 pathway signaling. Hence, miR-155 is a possible therapeutic approach to endothelial senescence in the development of cardiovascular diseases.

Epigenetic mechanisms in diabetic complications and metabolic memory.

The incidence of diabetes and its associated micro- and macrovascular complications is greatly increasing worldwide. The most prevalent vascular complications of both type 1 and type 2 diabetes include nephropathy, retinopathy, neuropathy and cardiovascular diseases. Evidence suggests that both genetic and environmental factors are involved in these pathologies. Clinical trials have underscored the beneficial effects of intensive glycaemic control for preventing the progression of complications. Accumulating evidence suggests a key role for epigenetic mechanisms such as DNA methylation, histone post-translational modifications in chromatin, and non-coding RNAs in the complex interplay between genes and the environment. Factors associated with the pathology of diabetic complications, including hyperglycaemia, growth factors, oxidant stress and inflammatory factors can lead to dysregulation of these epigenetic mechanisms to alter the expression of pathological genes in target cells such as endothelial, vascular smooth muscle, retinal and cardiac cells, without changes in the underlying DNA sequence. Furthermore, long-term persistence of these alterations to the epigenome may be a key mechanism underlying the phenomenon of 'metabolic memory' and sustained vascular dysfunction despite attainment of glycaemic control. Current therapies for most diabetic complications have not been fully efficacious, and hence a study of epigenetic mechanisms that may be involved is clearly warranted as they can not only shed novel new insights into the pathology of diabetic complications, but also lead to the identification of much needed new drug targets. In this review, we highlight the emerging role of epigenetics and epigenomics in the vascular complications of diabetes and metabolic memory.

ß-galactosyl-pyrrolidinyl diazeniumdiolate: an efficient tool to investigate nitric oxide functions on promoting cell death.

Nitric oxide (NO) is an active free radical gas that plays crucial roles in a broad range of biological processes. Extremely short half-life makes it difficult to use NO directly in research. It has been suggested that different concentrations of NO may lead to quite opposite results on cytotoxicity. However, the net effect of intracellular NO on tumor cell death has been controversial, partly because it is hard to precisely control the amount of NO generated exclusively within the target cells. Therefore, we have developed a cell-specific NO donor, ß-galactosyl-pyrrolidinyl diazeniumdiolate (ß-Gal-NONOate), in hopes of simulating the actual effects of intracellularly derived NO on the patterns of cell death as well as investigating its underlying mechanisms. In this study, by using three different tumor cell models, we showed that ß-Gal-NONOate could steadily transport NO into the target cells with similar delivery efficiencies and exerted a determinative effect on cell death. In addition, ß-Gal-NONOate-derived intracellular NO could provoke both apoptosis and necrosis in a concentration-dependent manner. While lower NO concentration primarily induced apoptosis, higher NO concentration mainly triggered necrosis. Moreover, the intrinsic apoptotic pathway, characterized by rapid Ca²âº overload and subsequent mitochondrial damage, was the collective mechanism responsible for the apoptotic death in all the three tumor cell lines. Taken together, since this cell-specifically derived NO is cheap to use and easy to quantify, ß-Gal-NONOate might be used as a novel and ideal tool to standardize intracellular NO generation and evaluate its net effects in different cellular and experimental settings in the coming future.

Enhanced chemical and biological activities of a newly biosynthesized eugenol glycoconjugate, eugenol α-D-glucopyranoside.

Eugenol, the essential component (over 90 %) of clove oil from Eugenia caryophyllata Thunb. (Myrtaceae), is a phenolic compound well known for its versatile pharmacological actions, including analgesic, local anesthetic, anti-inflammatory, antimicrobial, antitumor, and hair-growing effects. However, the application of eugenol is greatly limited mainly because of its unwanted physicochemical properties, such as low solubility, liability to sublimation, and pungent odor. Since glycosylation has been suggested to improve the physicochemical and biological properties of the parental compound, we have previously developed a novel and efficient way to biosynthesize highly purified eugenol α-D-glucopyranoside (α-EG). In light of the widely acknowledged importance of pure eugenol and the potential superiority of the glycosylation, it is crucial to further explore and compare the physicochemical and biological properties of these two phenolic compounds. In this study, we demonstrate that glucosylation is a promising method for modification of phenolic compound, and that α-EG is superior over its parent eugenol, in all of the tested aspects, including physicochemical properties, antioxidation activity, and antimicrobial and antitumor activities. These results strongly suggest that α-EG, as a novel prodrug, may serve as a useful probe and potential therapeutic drug in both fundamental research and clinical application in the coming future.

Imbalance of helper T cell subtypes and adipokine secretion in perivascular adipose tissue as a trigger of atherosclerosis in chronic Porphyromonas gingivalis W83 infection.

Periodontal disease, a prevalent oral disease, is an independent risk factor for atherosclerosis. Porphyromonas gingivalis (P.g), a keystone pathogen of periodontal disease, contributes to the pathogenesis of atherosclerosis. However, the exact mechanism remains unclear. An increasing number of studies have proposed the atherogenic influence of perivascular adipose tissue (PVAT) in pathological conditions including hyperlipidemia and diabetes. Nevertheless, the role of PVAT in atherosclerosis promoted by P.g infection has not been explored. In our study, we investigated the association between P.g colonization in PVAT and progression of atherosclerosis through experiments on clinical samples. We further investigated P.g invasion of PVAT, PVAT inflammation, aortic endothelial inflammation, aortic lipid deposition, and systemic inflammation in C57BL/6 J mice with or without P.g infection at 20, 24, and 28 weeks of age. PVAT inflammation, characterized by imbalance in Th1/Treg and dysregulated adipokine levels, was associated with P.g invasion, preceding endothelial inflammation that occurred independently of its direct invasion. The phenotype of systemic inflammation coincided with that of PVAT inflammation, but systemic inflammation occurred after endothelial inflammation. Therefore PVAT inflammation in early atherosclerosis could be a primary trigger of aortic endothelial inflammation and lipid deposition in chronic P.g infection, through the dysregulated paracrine secretion of T helper-1-related adipokines.

Genetic association of lipids and lipid-lowering drug target genes with non-alcoholic fatty liver disease.

BACKGROUND: Some observational studies found that dyslipidaemia is a risk factor for non-alcoholic fatty liver disease (NAFLD), and lipid-lowering drugs may lower NAFLD risk. However, it remains unclear whether dyslipidaemia is causative for NAFLD. This Mendelian randomisation (MR) study aimed to explore the causal role of lipid traits in NAFLD and evaluate the potential effect of lipid-lowering drug targets on NAFLD. METHODS: Genetic variants associated with lipid traits and variants of genes encoding lipid-lowering drug targets were extracted from the Global Lipids Genetics Consortium genome-wide association study (GWAS). Summary statistics for NAFLD were obtained from two independent GWAS datasets. Lipid-lowering drug targets that reached significance were further tested using expression quantitative trait loci data in relevant tissues. Colocalisation and mediation analyses were performed to validate the robustness of the results and explore potential mediators. FINDINGS: No significant effect of lipid traits and eight lipid-lowering drug targets on NAFLD risk was found. Genetic mimicry of lipoprotein lipase (LPL) enhancement was associated with lower NAFLD risks in two independent datasets (OR1 = 0.60 [95% CI 0.50-0.72], p1 = 2.07 × 10-8; OR2 = 0.57 [95% CI 0.39-0.82], p2 = 3.00 × 10-3). A significant MR association (OR = 0.71 [95% CI, 0.58-0.87], p = 1.20 × 10-3) and strong colocalisation association (PP.H4 = 0.85) with NAFLD were observed for LPL expression in subcutaneous adipose tissue. Fasting insulin and type 2 diabetes mediated 7.40% and 9.15%, respectively, of the total effect of LPL on NAFLD risk. INTERPRETATION: Our findings do not support dyslipidaemia as a causal factor for NAFLD. Among nine lipid-lowering drug targets, LPL is a promising candidate drug target in NAFLD. The mechanism of action of LPL in NAFLD may be independent of its lipid-lowering effects. FUNDING: Capital's Funds for Health Improvement and Research (2022-4-4037). CAMS Innovation Fund for Medical Sciences (CIFMS, grant number: 2021-I2M-C&T-A-010).

Early 6 months usage of single anTiplAtelet OR anTicoAgulant followed by single antiplatelet after transcatheter aortic valve replacement: protocol for a multicentre, open-label, randomised controlled clinical trial.

INTRODUCTION: The strategy for initiating antithrombotic therapy to prevent bioprosthetic valve thrombosis (BPVT) after transcatheter aortic valve replacement (TAVR) remains uncertain. There is still lacking evidence on the efficacy and safety of early 6 months usage of single-antiplatelet therapy (SAPT) or oral anticoagulant (OAC) after TAVR in patients without anticoagulant indications. METHODS AND ANALYSIS: This is a multicentre, randomised controlled, open-label trial, and 650 patients undergoing TAVR from 13 top TAVR centres in China will be recruited. Each eligible participant will be randomly assigned to two groups (1:1 ratio) as (1) SAPT (aspirin 75-100 mg for 6 months) group or (2) OAC group (warfarin, therapeutic international normalised ratio at 1.8-2.5 for 6 months), both followed by sequential aspirin 75-100 mg for 6 months. Participants in both groups will be invited for three follow-up visits of 1, 6 and 12 months after discharge. We will use both the net clinical benefit endpoint (composite of all-cause mortality, myocardial infarction, stroke/transient ischaemic attacks, peripheral artery thrombosis, intracardiac thrombosis and major bleeding and disabling or life-threatening bleeding) and the BPVT endpoint evaluated by four-dimensional CT as our primary endpoints. P value of <0.05 of two-sided test will be considered statistically significant. ETHICS AND DISSEMINATION: The present study was approved by the Institutional Review Boards at Fuwai Hospital, National Center for Cardiovascular Diseases of China (Approval No. 2023-1947). All patients will be informed of the details of the study and will sign an informed consent prior to inclusion in the study. Results of this study will be published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT05375474.

Discovery of a series of 2-(1H-pyrazol-1-yl)pyridines as ALK5 inhibitors with potential utility in the prevention of dermal scarring.

A series of 2-(1H-pyrazol-1-yl)pyridines are described as inhibitors of ALK5 (TGFß receptor I kinase). Modeling compounds in the ALK5 kinase domain enabled some optimization of potency via substitutions on the pyrazole core. One of these compounds PF-03671148 gave a dose dependent reduction in TGFß induced fibrotic gene expression in human fibroblasts. A similar reduction in fibrotic gene expression was observed when PF-03671148 was applied topically in a rat wound repair model. Thus these compounds have potential utility for the prevention of dermal scarring.

Oridonin attenuates LPS-induced early pulmonary fibrosis by regulating impaired autophagy, oxidative stress, inflammation and EMT.

CONTEXT: Oridonin (Ori) possesses anti-inflammatory, antioxidant and antitumor properties. However, the effects of Ori on Lipopolysaccharide (LPS)-induced early pulmonary fibrosis remain unclear. OBJECTIVE: We evaluated the protective effects of Ori on the mice model of pulmonary fibrosis. MATERIALS AND METHODS: The BALB/C mice were given LPS (1 mg/kg) or Ori (20 mg/kg) according to experimental grouping. Then the left lung tissues were used for HE, immunohistochemical and Masson staining, and the right lung tissues were used for hydroxyproline measurement and western blot experiments. Bronchoalveolar lavage fluid was collected for Giemsa staining. RESULTS: The high levels of hydroxyproline induced by LPS were reduced by Ori treatment. Immunohistochemical staining and western blot analysis showed that Ori inhibited the increased levels of fibrosis-related proteins (α-smooth muscle actin, transforming growth factor-ß, Collagen Ⅰ and phosphorylated-smad). Additionally, Ori treatment increased E-cadherin levels and decreased in Snail and Slug levels. Besides, Ori could suppress LPS-induced the infiltration of neutrophils and activation of the NLRP3 inflammasome. In addition, LPS caused the upregulation of NADPH oxidase 4 and exacerbated lung fibrosis. As the activator of NF-E2 related factor-2, Ori exerted protective effects in this animal model. Moreover, Ori reversed the LPS-triggered increases in Beclin-1, P62/sequestosome 1, autophagy related 3 and LC3. CONCLUSIONS: These findings suggested that Ori protected against LPS-induced early pulmonary fibrosis by inhibiting NLRP3-dependent inflammation, NADPH oxidase 4-dependent oxidative stress, the impaired autophagy and epithelial mesenchymal transformation.

Identification of Key Non-coding RNAs and Transcription Factors in Calcific Aortic Valve Disease.

Background: Calcific aortic valve disease (CAVD) is one of the most frequently occurring valvular heart diseases among the aging population. Currently, there is no known pharmacological treatment available to delay or reverse CAVD progression. The regulation of gene expression could contribute to the initiation, progression, and treatment of CAVD. Non-coding RNAs (ncRNAs) and transcription factors play essential regulatory roles in gene expression in CAVD; thus, further research is urgently needed. Materials and Methods: The gene-expression profiles of GSE51472 and GSE12644 were obtained from the Gene Expression Omnibus database, and differentially expressed genes (DEGs) were identified in each dataset. A protein-protein-interaction (PPI) network of DEGs was then constructed using the Search Tool for the Retrieval of Interacting Genes/Proteins database, and functional modules were analyzed with ClusterOne plugin in Cytoscape. Furthermore, Gene Ontology-functional annotation and Kyoto Encyclopedia of Genes and Genomes-pathway analysis were conducted for each functional module. Most crucially, ncRNAs and transcription factors acting on each functional module were separately identified using the RNAInter and TRRUST databases. The expression of predicted transcription factors and key genes was validated using GSE51472 and GSE12644. Furthermore, quantitative real-time PCR (qRT-PCR) experiments were performed to validate the differential expression of most promising candidates in human CAVD and control samples. Results: Among 552 DEGs, 383 were upregulated and 169 were downregulated. In the PPI network, 15 functional modules involving 182 genes and proteins were identified. After hypergeometric testing, 45 ncRNAs and 33 transcription factors were obtained. Among the predicted transcription factors, CIITA, HIF1A, JUN, POU2F2, and STAT6 were differentially expressed in both the training and validation sets. In addition, we found that key genes, namely, CD2, CD86, CXCL8, FCGR3B, GZMB, ITGB2, LY86, MMP9, PPBP, and TYROBP were also differentially expressed in both the training and validation sets. Among the most promising candidates, differential expressions of ETS1, JUN, NFKB1, RELA, SP1, STAT1, ANCR, and LOC101927497 were identified via qRT-PCR experiments. Conclusion: In this study, we identified functional modules with ncRNAs and transcription factors involved in CAVD pathogenesis. The current results suggest candidate molecules for further research on CAVD.

Prognostic value of blood pressure and resting heart rate in patients with tricuspid regurgitation.

Background: The prognostic value of blood pressure (BP) and resting heart rate (RHR) in tricuspid regurgitation (TR) patients is unknown. Aims: This study aimed to investigate the associations of BP and RHR with all-cause mortality in patients with TR. Methods: A total of 2,013 patients with moderate or severe TR underwent echocardiography and BP measurement. The associations of routinely measured BP and RHR with 2-year all-cause mortality were analyzed. Results: The cohort had 45.9% male patients and a mean age of 62.5 ± 15.9 years. At the 2-year follow-up, 165 patient deaths had occurred. The risk of death decreased rapidly, negatively correlating with systolic blood pressure (SBP) up to 120 mmHg and diastolic blood pressure (DBP) up to 70 mmHg. For RHR, the risk increased in direct proportion, starting at 80 beats per min. After adjusting for age, sex, body mass index (BMI), diabetes, coronary heart disease, pulmonary hypertension, estimated glomerular filtration rate (eGFR), and NYHA class, SBP [hazard ratio (HR):0.89; 95% CI:0.823-0.957 per 10 mmHg increase; P =0.002], DBP (HR:0.8; 95% CI:0.714-0.908 per 10 mmHg increase; P < 0.001), and RHR (HR: 1.1; 95% CI: 1.022-1.175 per 10 beats per min increase; P = 0.011) were independently associated with all-cause mortality. These associations persisted after further adjustments for echocardiographic indices, medications, serological tests, and etiologies. Conclusion: In this cohort of patients with TR, routinely measured BP and RHR were associated with all-cause mortality independently. However, further large-scale, high-quality studies are required to validate our findings.

Naoxintong capsules modulates tumor necrosis factor--induced endothelial senescence through silent information regulator 1 signaling.

OBJECTIVE: To investigate the protective effects of Naoxintong capsules ( NXT)on tumor necrosis factor-α (TNF-α) -induced senescence inendothelial cells and its mechanism. METHODS: Human umbilical vascular endothelial cells (HUVECs) were treated with TNF-α ± NXT and assessed for silent information regulator 1 (SIRT1) expression and signaling. Cells were stained with beta-galactosidase to assess the levels of cellular senescence. SIRT1 was silenced through siRNA transfection. RESULTS: TNF-α treatment led to the downregulation of SIRT1, resulting in forkhead box O1 (FoxO-1) acetylation, p53 acetylation and enhanced p21 expression. Following TNF-α treatment, higher SA ß-Gal activity improved. TNF-α enhanced the migration of HUVECs and increased SIRT1 expression, both of which were attenuated by NXT treatment. The downstream targets of SIRT1 including FoxO-1/p53/p21 were also modulated, and HUVECs were protected from TNF-α-induced senescence. In contrast, the NXT-mediated protection was prevented by SIRT1 silencing. CONCLUSIONS: These findings suggest that sustained endothelial senescence can be induced by TNF-α stimulation via the SIRT1/FoxO-1/p53/p21 pathway. The protection of NXT against TNF- was partially mediated through its effects on SIRT1. This highlights the promise of NXT as a therapeutic for atherosclerosis.

Sevelamer Attenuates Bioprosthetic Heart Valve Calcification.

Objective: Sevelamer hydrochloride is a phosphate binder used to treat hyperphosphatemia in chronic kidney disease (CKD) patients that can reduce valvular and vascular calcification. The aim of this study was to examine the effects of sevelamer treatment on calcification in bioprosthetic heart valves (BHVs). Methods: Wister rats were randomly divided into three groups according to sevelamer intake and implantation (sham-sham operation; implant-implantation and normal diet, implant+S implantation, and sevelamer diet). Two kinds of BHVs-bovine pericardium treated with glutaraldehyde (GLUT) or non-GLUT techniques-were implanted in rat dorsal subcutis at 4 weeks. After implantation, sevelamer was administered to the implant+S group. The animals were executed at days 0 (immediately after implantation), 7, 14, 28, and 56. Calcium levels were determined by atomic absorption spectroscopy and von Kossa staining. Serum biochemistry analysis, Western blotting, real-time quantitative polymerase chain reaction, alkaline phosphatase activity measurement, histopathologic analysis, immunohistochemistry, and enzyme-linked immunosorbent assay were conducted to identify the anti-calcification mechanism of sevelamer. Results: Non-GLUT crosslinking attenuates BHV calcification. Serum phosphate and calcium remained unreactive to sevelamer after a 14-day treatment. However, the mean calcium level in the implant+S group was significantly decreased after 56 days. In addition, the PTH level, inflammatory cell infiltration, system and local inflammation, and expression of Bmp2, Runx2, Alp, IL-1ß, IL-6, and TNF-α were significantly reduced in the implant+S group. Conclusion: Sevelamer treatment significantly attenuated the calcification of BHVs and had anti-inflammation effects that were independent from serum calcium and phosphate regulation. Thus, sevelamer treatment might be helpful to improve the longevity of BHVs.

Pharmacokinetics and tissue distribution of methcathinone in rabbits.

Methcathinone is one of the most commonly abused designer narcotics. The pharmacokinetics and tissue distribution of methcathinone is not well understood. In this study, methcathinone was intravenously or intragastrically administered to rabbits in order to investigate the pharmacokinetics and tissue distribution of methcathinone. The plasma concentrations of methcathinone and its metabolite cathinone at various timepoints post-methcathinone administration as well as the distribution of methcathinone and cathinone in various tissues were determined and quantified using a liquid chromatography-tandem mass spectrometry (LC-MS/MS). According to our results, the elimination of methcathinone and cathinone was faster after intravenous administration than that after intragastric administration. The methcathinone or cathinone concentration in the plasma dramatically dropped at 16-18 h post-methcathinone administration followed by a rebound. Gastric content and stomach tissue could be better samples for the identification of methcathinone abuse by oral administration while bile and stomach tissue could be ideal samples for the identification of methcathinone abuse in intravenous injection cases. The pharmacokinetic characteristics and tissue distribution pattern of methcathinone and its metabolite cathinone described in this study could benefit future study on identification and control of methcathinone abuse in forensic toxicological analysis.

Pterostilbene Protects Against Lipopolysaccharide/D-Galactosamine-Induced Acute Liver Failure by Upregulating the Nrf2 Pathway and Inhibiting NF-κB, MAPK, and NLRP3 Inflammasome Activation.

The purpose of this study was to evaluate the protective effect of pterostilbene (Psb) against lipopolysaccharide and D-galactosamine (L/D)-induced acute liver failure (ALF) in mice and its potential mechanisms. Histology of liver was detected by H&E staining. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels in serum and malondialdehyde (MDA), myeloperoxidase (MPO), glutathione (GSH), and superoxide dismutase (SOD) contents in liver were examined using detection kits. The levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and interleukin-1ß (IL-1ß) secretion were detected by ELISA. Meanwhile, MAPK, NF-κB, NLRP3 inflammasome, and Nrf2 were assessed by western blotting. Our findings showed that pretreatment with Psb protected against L/D-induced ALF by lowering the lethality, improving liver histology, reducing ALT, AST, IL-6, IL-1ß, TNF-α, MDA, and MPO levels, and boosting liver GSH content and SOD activity. Moreover, Psb pretreatment effectively suppressed inflammation by decreasing NLRP3 inflammasome, MAPK, and NF-κB pathway activations. Moreover, Psb pretreatment efficiently enhanced the expression of several antioxidant enzymes, mainly depending on Nrf2 activation. This was the first study to demonstrate that Psb protects against L/D-induced ALF by inactivating MAPK, NF-κb, and NLRP3 inflammasome and upregulating the Nrf2 signaling pathway, indicating a potential therapeutic application for ALF treatment.

Prognostic Value of N-Terminal Pro-B-Type Natriuretic Peptide in Elderly Patients With Valvular Heart Disease.

BACKGROUND: N-terminal pro-B-type natriuretic peptide (NT-proBNP) may reflect early prognosis in patients with valvular heart disease (VHD). OBJECTIVES: The aim of this study was to examine the association between NT-proBNP and mortality in elderly patients with VHD. METHODS: A total of 5,983 elderly patients (age ≥60 years) with moderate or severe VHD underwent echocardiography and NT-proBNP measurement. VHD examined included aortic stenosis, aortic regurgitation, mitral stenosis, mitral regurgitation, tricuspid regurgitation, and multivalvular heart disease. NT-proBNP ratio was defined as measured NT-proBNP relative to the maximal normal values specific to age and sex. Disease-specific thresholds were defined on the basis of penalized splines and maximally selected rank statistics. RESULTS: The cohort had a mean age of 71.1 ± 7.6 years. At 1-year follow-up, 561 deaths (9.4%) had occurred. In penalized splines, relative hazards showed a monotonic increase with greater NT-proBNP ratio for death with different VHDs (p < 0.001 for all) except mitral stenosis. Higher NT-proBNP ratio, categorized by disease-specific thresholds, was independently associated with mortality (overall adjusted hazard ratio: 1.99; 95% confidence interval: 1.76 to 2.24; p < 0.001). Different subtypes of VHD all incurred excess mortality with elevated NT-proBNP ratio, with the strongest association detected for aortic stenosis (adjusted hazard ratio: 10.5; 95% confidence interval: 3.9 to 28.27; p < 0.001). The addition of NT-proBNP ratio to the prediction algorithm including traditional risk factors improved outcome prediction (overall net reclassification index = 0.28; 95% CI: 0.24 to 0.34; p < 0.001; likelihood ratio test p < 0.001). Results remained consistent in patients under medical care, with normal left ventricular ejection fractions, and with primary VHD. CONCLUSIONS: NT-proBNP provides incremental prognostic information for mortality in various VHDs. It could aid in risk stratification as a pragmatic and versatile biomarker in elderly patients.

Structures of human MAP kinase kinase 1 (MEK1) and MEK2 describe novel noncompetitive kinase inhibition.

MEK1 and MEK2 are closely related, dual-specificity tyrosine/threonine protein kinases found in the Ras/Raf/MEK/ERK mitogen-activated protein kinase (MAPK) signaling pathway. Approximately 30% of all human cancers have a constitutively activated MAPK pathway, and constitutive activation of MEK1 results in cellular transformation. Here we present the X-ray structures of human MEK1 and MEK2, each determined as a ternary complex with MgATP and an inhibitor to a resolution of 2.4 A and 3.2 A, respectively. The structures reveal that MEK1 and MEK2 each have a unique inhibitor-binding pocket adjacent to the MgATP-binding site. The presence of the potent inhibitor induces several conformational changes in the unphosphorylated MEK1 and MEK2 enzymes that lock them into a closed but catalytically inactive species. Thus, the structures reported here reveal a novel, noncompetitive mechanism for protein kinase inhibition.