Quantitative laser‐induced breakdown spectroscopy (LIBS) is successfully used for in‐vitro analysis of early stage calcification in aortic valvular interstitial cells (VICs). LIBS results indicate 5‐fold improvement in the detection limit of calcium deposition in VICs over cell histology techniques involving staining and colorimetric calcium assays. These results can establish LIBS at the forefront of early detection of calcification in VICs for pathological studies on Calcific Aortic Valve Disease (CAVD). Further details can be found in the article by Seyyed Ali Davari et al. ( e201600288 ).
Both aortic and mitral valves calcify in pathological conditions; however, the prevalence of aortic valve calcification is high whereas mitral valve leaflet calcification is somewhat rare. Patterns of valvular calcification may differ due to valvular architecture, but little is known to that effect. In this study, we investigated the intrinsic osteogenic differentiation potential of aortic versus mitral valve interstitial cells provided minimal differentiation conditions. For the assessment of calcification at the cellular level, we used classic inducers of osteogenesis in stem cells: β-glycerophosphate (β-Gly), dexamethasone (Dex), and ascorbate (Asc). In addition to proteomic analyses, osteogenic markers and calcium precipitates were evaluated across treatments of aortic and mitral valve cells. The combination of β-Gly, Asc, and Dex induced aortic valve interstitial cells to synthesize extracellular matrix, overexpress osteoblastic markers, and deposit calcium. However, no strong evidence showed the calcification of mitral valve interstitial cells. Mitral cells mainly responded to Asc and Dex by cell activation. These findings provide a deeper understanding of the physiological properties of aortic and mitral valves and tendencies for calcific changes within each valve type, contributing to the development of future therapeutics for heart valve diseases. 相似文献
Nicotinamide adenine dinucleotide (NAD+) is crucial for cell energy metabolism and many signalling processes. Recently, we proved the role of ecto-enzymes in controlling adenine nucleotide–dependent pathways during calcific aortic valve disease (CAVD). This study aimed to investigate extracellular hydrolysis of NAD+ and mononucleotide nicotinamide (NMN) in aortic valves and aorta fragments of CAVD patients and on the inner aortic surface of ecto-5′-nucleotidase knockout mice (CD73−/−). Human non-stenotic valves (n = 10) actively converted NAD+ and NMN via both CD73 and NAD+-glycohydrolase (CD38) according to our analysis with RP-HPLC and immunofluorescence. In stenotic valves (n = 50), due to reduced CD73 activity, NAD+ was degraded predominantly by CD38 and additionally by ALP and eNPP1. CAVD patients had significantly higher hydrolytic rates of NAD+ (0.81 ± 0.07 vs 0.56 ± 0.10) and NMN (1.12 ± 0.10 vs 0.71 ± 0.08 nmol/min/cm2) compared with controls. CD38 was also primarily engaged in human vascular NAD+ metabolism. Studies using specific ecto-enzyme inhibitors and CD73−/− mice confirmed that CD73 is not the only enzyme involved in NAD+ and NMN hydrolysis and that CD38 had a significant contribution to these pathways. Modifications of extracellular NAD+ and NMN metabolism in aortic valve cells may be particularly important in valve pathology and could be a potential therapeutic target. 相似文献
Patients with end‐stage renal disease (ESRD) have elevated circulating calcium (Ca) and phosphate (Pi), and exhibit accelerated progression of calcific aortic valve disease (CAVD). We hypothesized that matrix vesicles (MVs) initiate the calcification process in CAVD. Ca induced rat valve interstitial cells (VICs) calcification at 4.5 mM (16.4‐fold; p < 0.05) whereas Pi treatment alone had no effect. Ca (2.7 mM) and Pi (2.5 mM) synergistically induced calcium deposition (10.8‐fold; p < 0.001) in VICs. Ca treatment increased the mRNA of the osteogenic markers Msx2, Runx2, and Alpl (p < 0.01). MVs were harvested by ultracentrifugation from VICs cultured with control or calcification media (containing 2.7 mM Ca and 2.5 mM Pi) for 16 hr. Proteomics analysis revealed the marked enrichment of exosomal proteins, including CD9, CD63, LAMP‐1, and LAMP‐2 and a concomitant up‐regulation of the Annexin family of calcium‐binding proteins. Of particular note Annexin VI was shown to be enriched in calcifying VIC‐derived MVs (51.9‐fold; p < 0.05). Through bioinformatic analysis using Ingenuity Pathway Analysis (IPA), the up‐regulation of canonical signaling pathways relevant to cardiovascular function were identified in calcifying VIC‐derived MVs, including aldosterone, Rho kinase, and metal binding. Further studies using human calcified valve tissue revealed the co‐localization of Annexin VI with areas of MVs in the extracellular matrix by transmission electron microscopy (TEM). Together these findings highlight a critical role for VIC‐derived MVs in CAVD. Furthermore, we identify calcium as a key driver of aortic valve calcification, which may directly underpin the increased susceptibility of ESRD patients to accelerated development of CAVD. 相似文献
Valve disease and particularly calcific aortic valve disease (CAVD) and diabetes (DM) are progressive diseases constituting a global health burden for all aging societies (Progress in Cardiovascular Diseases. 2014;56(6):565: Circulation Research. 2021;128(9):1344). Compared to non-diabetic individuals (The Lancet. 2008;371(9626):1800: The American Journal of Cardiology. 1983;51(3):403: Journal of the American College of Cardiology. 2017;69(12):1523), the diabetic patients have a significantly greater propensity for cardiovascular disorders and faster degeneration of implanted bioprosthetic aortic valves. Previously, using an original experimental model, the diabetic-hyperlipemic hamsters, we have shown that the earliest alterations induced by these conditions occur at the level of the aortic valves and, with time these changes lead to calcifications and CAVD. However, there are no pharmacological treatments available to reverse or retard the progression of aortic valve disease in diabetes, despite the significant advances in the field. Therefore, it is critical to uncover the mechanisms of valve disease progression, find biomarkers for diagnosis and new targets for therapies. This review aims at presenting an update on the basic research in CAVD in the context of diabetes. We provide an insight into the accumulated data including our results on diabetes-induced progressive cell and molecular alterations in the aortic valve, new potential biomarkers to assess the evolution and therapy of the disease, advancement in targeted nanotherapies, tissue engineering and the potential use of circulating endothelial progenitor cells in CAVD. 相似文献
ABSTRACTNT5E encodes ecto-5′-nucleotidase (e5NT, CD73) which hydrolyses extracellular AMP to adenosine. Adenosine has been shown to play a protective role against aortic valve calcification (AVC). We identified two nonsynonymous missense single nucleotide polymorphisms (c.1126A > G, p.T376A and c.1136T > C, p.M379T) in exon 6 of the human NT5E gene. Since both substitutions might affect e5NT activity and consequently alter extracellular adenosine levels, we evaluated the association between NT5E alleles and calcific aortic valve disease in 119 patients (95 patients with AVC and 24 controls). In AVC patients, the frequency of the G allele at c.1126 and the frequency of the GG genotype as well as the frequency of the C allele at c.1136, and the frequencies of CC and TC genotypes tended to be higher as compared to controls. The allele and genotype frequencies in AVC patients and controls were also compared to those calculated from the 1000 Genomes Project data for control individuals of European ancestry (n = 503). We found that the frequency of the C allele at c.1136 is significantly higher in patients with AVC than in the European controls (0.111 vs. 0.054, P = 0.0052). Moreover, e5NT activity in aortic valves showed a trend toward lower levels in AVC patients with CC and TC genotypes than in those with the TT genotype. Our findings indicate that the genetic polymorphism of NT5E may contribute to the pathogenesis of calcific aortic valve disease and that the C allele of SNP c.1136 is associated with an increased risk of AVC. 相似文献
Bacteria are the primary cause of infectious diseases, making rapid and accurate identification crucial for timely pathogen diagnosis and disease control. However, traditional identification techniques such as polymerase chain reaction and loop-mediated isothermal amplification are complex, time-consuming, and pose infection risks. This study explores remote (~3 m) bacterial identification using laser-induced breakdown spectroscopy (LIBS) with a Cassegrain reflective telescope. Principal component analysis (PCA) was employed to reduce the dimensionality of the LIBS spectral data, and the accuracy of support vector machine (SVM) and Random Forest (RF) algorithms was compared. Multiple repeated experiments showed that the RF model achieved a classification accuracy, recall, precision, and F1-score of 99.81%, 99.80%, 99.79%, and 0.9979, respectively, outperforming the SVM model and providing more accurate remote bacterial identification. The method based on laser-induced plasma spectroscopy and machine learning has broad application prospects, supporting noncontact disease diagnosis, improving public health, and advancing medical research and technological development. 相似文献
Fibrotic aortic valve disease (FAVD) is an important cause of aortic stenosis, yet currently there is no effective treatment for FAVD due to its unknown etiology. The purpose of this study was to investigate whether deficiency in the anti‐aging Klotho gene (KL) promotes high‐fat‐diet‐induced FAVD and to explore the underlying molecular mechanism. Heterozygous Klotho‐deficient (KL+/?) mice and WT littermates were fed with a high‐fat diet (HFD) or normal diet for 13 weeks, followed by treatment with the AMPKα activator (AICAR) for an additional 2 weeks. A HFD caused a greater increase in collagen levels in the aortic valves of KL+/? mice than of WT mice, indicating that Klotho deficiency promotes HFD‐induced aortic valve fibrosis (AVF). AMPKα activity (pAMPKα) was decreased, while protein expression of collagen I and RUNX2 was increased in the aortic valves of KL+/? mice fed with a HFD. Treatment with AICAR markedly attenuated HFD‐induced AVF in KL+/? mice. AICAR not only abolished the downregulation of pAMPKα but also eliminated the upregulation of collagen I and RUNX2 in the aortic valves of KL+/? mice fed with HFD. In cultured porcine aortic valve interstitial cells, Klotho‐deficient serum plus cholesterol increased RUNX2 and collagen I protein expression, which were attenuated by activation of AMPKα by AICAR. Interestingly, silencing of RUNX2 abolished the stimulatory effect of Klotho deficiency on cholesterol‐induced upregulation of matrix proteins, including collagen I and osteocalcin. In conclusion, Klotho gene deficiency promotes HFD‐induced fibrosis in aortic valves, likely through the AMPKα–RUNX2 pathway. 相似文献
In the present study, the elemental compositions of fat and nerve tissue during their plasma mediated laser ablation are studied in the context of tissue differentiation for laser surgery applications by using Laser‐Induced Breakdown Spectroscopy (LIBS). Tissue samples of porcine fat and nerve were prepared as ex vivo experimental objects. Plasma mediated laser ablation is performed using an Nd : YAG laser in open air and under normal stray light conditions. The performed measurements suggest that the two tissue types show a high similarity in terms of qualitative elemental composition while at the same time revealing a distinct difference in the concentration of the constituent elements. Different analysis approaches are evaluated and discussed to optimize the tissue‐differentiation performance of the LIBS approach.
Ginsenoside, one of the active ingredients of Panax ginseng, has a variety of physiological and pharmacological actions in
various organs. However, little is known about the effects of ginsenosides on gastrointestinal (GI) motility. We studied the
modulation of pacemaker potentials by ginsenoside in the interstitial cells of Cajal (ICCs) using the whole-cell patch clamp
technique in the current clamp mode. Among ginsenosides, we investigated the effects of ginsenoside Rb1, Rg3 and Rf. While
externally applied Rb1 and Rg3 had no effects on pacemaker potentials, Rf caused membrane depolarization. The application
of flufenamic acid or niflumic acid abolished the generation of pacemaker potentials and inhibited the Rf-induced membrane
depolarization. Membrane depolarization induced by Rf was not inhibited by intracellular application of guanosine 5′-[β-thio]diphosphate
trilithium salt. Pretreatment with a Ca2+-free solution, thapsigargin, a Ca2+-ATPase inhibitor of the endoplasmic reticulum, U-73122, a phospholipase C inhibitor, or 2-APB, an IP3 receptor inhibitor,
abolished the generation of pacemaker potentials and suppressed Rfinduced actions. However, treatment with chelerythrine and
calphostin C, protein kinase C inhibitors, did not block Rf-induced effects on pacemaker potentials. These results suggest
that ginsenoside Rf modulates the pacemaker activities of ICCs and therby regulates intestinal motility. 相似文献
Herein, we hypothesized that pro‐osteogenic MicroRNAs (miRs) could play functional roles in the calcification of the aortic valve and aimed to explore the functional role of miR‐29b in the osteoblastic differentiation of human aortic valve interstitial cells (hAVICs) and the underlying molecular mechanism. Osteoblastic differentiation of hAVICs isolated from human calcific aortic valve leaflets obtained intraoperatively was induced with an osteogenic medium. Alizarin red S staining was used to evaluate calcium deposition. The protein levels of osteogenic markers and other proteins were evaluated using western blotting and/or immunofluorescence while qRT‐PCR was applied for miR and mRNA determination. Bioinformatics and luciferase reporter assay were used to identify the possible interaction between miR‐29b and TGF‐β3. Calcium deposition and the number of calcification nodules were pointedly and progressively increased in hAVICs during osteogenic differentiation. The levels of osteogenic and calcification markers were equally increased, thus confirming the mineralization of hAVICs. The expression of miR‐29b was significantly increased during osteoblastic differentiation. Furthermore, the osteoblastic differentiation of hAVICs was significantly inhibited by the miR‐29b inhibition. TGF‐β3 was markedly downregulated while Smad3, Runx2, wnt3, and β‐catenin were significantly upregulated during osteogenic induction at both the mRNA and protein levels. These effects were systematically induced by miR‐29b overexpression while the inhibition of miR‐29b showed the inverse trends. Moreover, TGF‐β3 was a direct target of miR‐29b. Inhibition of miR‐29b hinders valvular calcification through the upregulation of the TGF‐β3 via inhibition of wnt/β‐catenin and RUNX2/Smad3 signaling pathways. 相似文献
