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Diabetic cardiomyopathy (DCM) is ventricular dysfunction that occurs in patients with diabetes mellitus (DM), independent of recognized risk factors, such as coronary artery disease, hypertension, and valvular heart disease. Dual-specificity phosphatase 12 (DUSP12) is a dual-specificity phosphatase expressed in all tissues. Genome-wide linkage studies have found an association between DUSP12 and type 2 diabetes (T2D). However, the role of DUSP12 in DCM remains largely unknown. Ubiquitously expressed DUSP12 is involved in nonalcoholic fatty liver disease, bacterial infection, and myocardial hypertrophy and plays a critical role in tumorigenesis. Herein, we observed an increased expression of DUSP12 in a hyperglycemia cell model and a high-fat diet (HFD) mouse model. Heart-specific DUSP12-deficient mice showed severe cardiac dysfunction and remodeling induced by an HFD. DUSP12 deficiency exacerbated oxidative stress injury and apoptosis, whereas DUSP12 overexpression had the opposite effect. At the molecular level, DUSP12 physically bound to apoptotic signal-regulated kinase 1 (ASK1), promoted its dephosphorylation, and inhibited its action on c-Jun N-terminal kinase and p38 mitogen-activated protein kinase. Rescue experiments have shown that oxidative stress injury and apoptosis, exacerbated by DUSP12 deficiency, are alleviated by ASK1 inhibition. Therefore, we consider DUSP12 an important signaling pathway in DCM.

A variety of azetidine nitrones are prepared in moderate to good yields through copper(I) combined with 2-aminopyridine to catalyze skeletal rearrangement of

A variety of N-vinylindoles and N-vinylpyrroles were prepared in moderate to good yields through the nickel(II)-catalyzed [3 + 2] cycloaddition of α,β-unsaturated nitrones with allenoates under mild reaction conditions. A rational mechanism for the formation of N-vinylindoles was proposed based on the 18O-labeled experiments and key intermediates detected by high-resolution mass spectrometry trace experiments. The present method highlights a nickel(II)-controlled cyclization, atom-economical reaction, broad substrate scope, good functional group tolerance, and high Z-stereoselectivity for the enamine bond.

A variety of tetrahydroquinoline-fused bicycles bearing multiple stereocenters are prepared in good yields with high diastereoselectivity through Cu2O-catalyzed [4 + 2] cycloaddition of aza-ortho-quinone methides (ao-QMs) with bicyclic alkenes. Mechanistic studies reveal that the Cu(i) catalyst not only promotes the formation of ao-QMs through a radical process by single electron transfer but also accelerates [4 + 2] cycloaddition. The reaction was easily performed on gram scale and the obtained tetrahydroquinoline-fused bicycles can be converted to diverse tetrahydroquinoline scaffolds.

A nickel(II)-catalyzed oxygen transfer reaction of dibenzylideneacetone-derived N-vinyl-α,β-unsaturated nitrones has been identified for the preparation of polysubstituted 2-(pyridin-2-yl)ethanols in good yields with high atom economy. The scope of the method is described, and mechanistic experiments are discussed. The reaction was easily performed at gram scales, and pyrido[2,3-c]carbazole was obtained in moderate yield over three steps.

We describe a P-containing palladacycle-catalyzed regioselective Heck reaction of 2,3-dihydrofuran with diaryliodonium salts and aryl iodides to afford 2-aryl-2,5-dihydrofurans and 2-aryl-2,3-dihydrofurans, respectively, in good yields. Mechanistic studies revealed that the oxidative addition of diaryliodonium salts to palladacycles to form Pd(IV) species showed high chemoselectivity and that electron-rich aryl moieties were preferentially transferred to the Heck product. DFT calculations indicated that the regioselectivity-determining step is the reductive elimination reaction rather than the isomerization and reinsertion of Pd(IV)-hydride intermediates into the double bond.

An efficient one-pot synthesis of polysubstituted pyrrolizines from N-vinyl- α,β-unsaturated nitrones and activated alkynes through iron(III)/copper(II)-cocatalyzed [3 + 2] cycloaddition/[3,3]-rearrangement and sequential N-O bond cleavage was developed. The reaction first underwent [3 + 2] cycloaddition and [3,3]-rearrangement to afford nine-membered N-heterocycles, and then a controlled N-O bond cleavage of nine-membered rings by iron(III)/copper(II) cocatalysts delivered pyrrolizine scaffolds. A kinetic resolution of nine-membered ring compounds was achieved for the first time by using copper(II) acetate combined with a chiral PyBox ligand.

In this paper, a novel optical approach to double the sensitivity to angular rate of interferometric fiber optic gyroscope (IFOG) is proposed. Two fiber polarization combiner/splitters (FPCSs), as the key components, are added in the traditional IFOG light path. The FPCSs are able to either combine two orthogonal polarizations transmitting at two different polarization-maintaining fibers (PMFs) into the two orthogonal axes of one PMF, respectively, or split two polarizations transmitting at the two orthogonal axes of one PMF into two polarizations to transmit at two different PMFs, respectively. Through the specific placement and coupling of these two FPCSs, the incident light can transmit twice along the polarization-maintaining fiber coil (PMFC). The novel approach is verified experimentally and the experimental results show consistency with the theoretical analysis. The proposed approach is able to double the sensitivity of IFOGs and can increase the signal-to-noise ratio (SNR) without increasing the length of PMFC, which is very susceptible to environmental influences and is of great significance in the technical improvement of IFOGs, as well as the miniaturization of IFOGs.

Various benzoxazonines were synthesized through a formal [7 + 2] cycloaddition of arynes with N-vinyl-α,β-unsaturated nitrones under mild conditions. Controllable N–O bond cleavage of benzoxazonines afforded polysubstituted pyrrole-tethered benzopyrans and acyclic ketone-substituted phenols in moderate to good yields. Further transformations provided a facile approach to access useful building blocks with specific stereoselectivity.

Melatonin has been shown to inhibit myocardial infarction-induced apoptosis, its function in heart failure with preserved ejection fraction (HFpEF) has not been investigated. This study aimed to investigate whether melatonin attenuates obesity-related HFpEF. Male mice were fed a high-fat diet (HFD) from weaning to 6 months of age to induce HFpEF. The mice were orally administered melatonin (50 mg/kg) by 3 weeks. Diastolic function was significantly improved by melatonin supplementation in mice fed an HFD. Melatonin attenuated obesity-induced myocardial oxidative stress and apoptosis and promoted the secretion of C1q/tumour necrosis factor-related protein 3 (CTRP3) by adipose tissue. And depletion of circulating CTRP3 largely abolished melatonin-mediated cardio-protection. Melatonin-mediated secretion of adipocyte-derived CTRP3 activated NF-E2-related factor 2 (Nrf2), which were largely abrogated by knocking down CTRP3 in adipocytes or Nrf2 in cardiomyocytes. Nrf2 activation was mediated by miR-200a, and a miR-200a antagomir offset the effects of melatonin-conditioned medium on Nrf2 expression. Our results indicate that melatonin can be used to treat and prevent obesity-related HFpEF., Graphical abstract fx1, Highlights • Melatonin attenuates obesity-related heart failure with preserved ejection fraction. • Melatonin attenuates obesity-induced myocardial injury via adipose tissue-derived CTRP3. • Melatonin-mediated secretion of adipocyte-derived CTRP3 activates Nrf2 by miR-200a.

Rationale Complement C1q tumor necrosis factor related proteins (C1QTNFs) have been reported to have diverse biological influence on the cardiovascular system. C1QTNF1 is a member of the CTRP superfamily. C1QTNF1 is expressed in the myocardium; however, its function in myocytes has not yet been investigated. Objective To systematically investigate the roles of C1QTNF1 in angiotensin II (Ang II)-induced cardiac hypertrophy. Methods and results C1QTNF1 knock-out mice were used with the aim of determining the role of C1QTNF1 in cardiac hypertrophy in the adult heart. Data from experiments showed that C1QTNF1 was up-regulated during cardiac hypertrophic processes, which were triggered by increased reactive oxygen species. C1QTNF1 deficiency accelerated cardiac hypertrophy, fibrosis, inflammation responses, and oxidative stress with deteriorating cardiac dysfunction in the Ang II-induced cardiac hypertrophy mouse model. We identified C1QTNF1 as a negative regulator of cardiomyocyte hypertrophy in Ang II-stimulated neonatal rat cardiomyocytes using the recombinant human globular domain of C1QTNF1 and C1QTNF1 siRNA. Injection of the recombinant human globular domain of C1QTNF1 also suppressed the Ang II-induced cardiac hypertrophic response in vivo. The anti-hypertrophic effects of C1QTNF1 rely on AMPKa activation, which inhibits mTOR P70S6K phosphorylation. An AMPKa inhibitor abrogated the anti-hypertrophic effects of the recombinant human globular domain of C1QTNF1 both in vivo and vitro. Moreover, C1QTNF1-mediated AMPKa activation was triggered by the inhibition of PDE1-4, which subsequently activated the cAMP/PKA/LKB1 pathway. Conclusion Our results demonstrated that C1QTNF1 improves cardiac function and inhibits cardiac hypertrophy and fibrosis by increasing and activating AMPKa, suggesting that C1QTNF1 could be a therapeutic target for cardiac hypertrophy and heart failure.

Finding the novel drug from the effective components of traditional Chinese herbal medicine is a hotspot of the modern pharmacological research. Hyperoside (HYP) belongs to flavonoid glycosides, and it has various properties, such as anti-inflammation, anti-spasm, anti-diuretic, antitussive, lowering blood pressure, and lowering cholesterol effects as well as protective effects for the cardiac and cerebral blood vessels. The purpose of this study was to investigate the effects of HYP on inflammatory and apoptotic responses in vascular endothelial cells stimulated by lipopolysaccharide (LPS) and further to identify the possible mechanisms underlying these effects. In our study, human umbilical vein endothelial cells (HUVECs) were stimulated with 1 μg/mL LPS in the presence or absence of HYP (10, 20 and 50 μmol/L). Our results indicated that HYP alone exerted no cytotoxicity on HUVECs, while it had an up-regulatory effect on the viability of HUVECs induced by LPS in a dose-dependent manner; increased mRNA expression of IL-1β, IL-6, TNFα and iNOS induced by LPS was attenuated after treatment with HYP both in a dose-and time-dependent manner; LPS-induced HUVECs apoptosis and cleaved-caspase 8, 9, 3 were all significantly reduced by HYP. Furthermore, the possible pathway involved in apoptosis and inflammation by HYP was detected, and the results showed that when treated with HYP, LPS-induced mitochondrial membrane instability was significantly inhibited through up-regulation of Bcl-2 and down-regulation of Bax. Furthermore, the expression of TLR4 and the phosphorylation of IκBα and p65 in LPS-treated cells were blocked by HYP. Our results suggested that HYP treatment prevented HUVECs from LPSinduced inflammation and apoptosis responses, which might be mediated by inhibiting TLR4/NFκB pathway.

The effects of poly(vinylpyrrolidone ) (PVP) and poly(methyl methacrylate) (PMMA) additives on poly(vinylidene fluoride) (PVDF) hollow fiber membranes fabricated via the thermally induced phase separation process were studied. The addition of PVP showed a significant effect on the membrane structure, while addition of PMMA had little effect. In the PVDF/PVP blend membrane, the growth of spherulites was effectively inhibited due to the low compatibility between PVDF and PVP. An asymmetric structure consisting of a dense skin layer near the outer surface and a spherulite structure inside the membrane was obtained in this blend membrane. Measurements of tensile strength and water contact angle were also carried out. In contrast to the addition of PMMA, the addition of PVP significantly improved the maximum stress, elongation and hydrophilicity of membranes. Filtration experiments with BSA solution showed that PVDF/PVP membranes had much better fouling resistance than PVDF/PMMA and plain PVDF membranes.

Background: Management of influenza, a major contributor to the worldwide disease burden, is complicated by lack of reliable methods for early identification of susceptible individuals. Identification of molecular markers that can augment existing diagnostic tools for prediction of severity can be expected to greatly improve disease management capabilities. Methodology/Principal Findings: We have analyzed cytokines, proteome flux and protein adducts in bronchoalveolar lavage (BAL) and sera from mice infected with influenza A virus (PR8 strain) using a previously established non-lethal model of influenza infection. Through detailed cytokine and protein adduct measurements of murine BAL, we first established the temporal profile of innate and adaptive responses as well as macrophage and neutrophil activities in response to influenza infection. A similar analysis was also performed with sera from a longitudinal cohort of influenza patients. We then used an iTRAQ-based, comparative serum proteome analysis to catalog the proteome flux in the murine BAL during the stages correlating with “peak viremia,” “inflammatory damage,” as well as the “recovery phase.” In addition to activation of acute phase responses, a distinct class of lung proteins including surfactant proteins was found to be depleted from the BAL coincident with their “appearance” in the serum, presumably due to leakage of the protein following loss of the integrity of the lung/epithelial barrier. Serum levels of at least two of these proteins were elevated in influenza patients during the febrile phase of infection compared to healthy controls or to the same patients at convalescence. Conclusions/Significance: The findings from this study provide a molecular description of disease progression in a mouse model of influenza and demonstrate its potential for translation into a novel class of markers for measurement of acute lung injury and improved case management., Singapore. National Research Foundation, Singapore-MIT Alliance for Research and Technology (ID-IRG research program)