WSB1, a Hypoxia-Inducible E3 Ligase, Promotes Myofibroblast Accumulation and Attenuates Alveolar Epithelial Regeneration in Mouse Lung Fibrosis.

Idiopathic pulmonary fibrosis is a progressive interstitial lung disease for which there is no curative therapy available. Repetitive alveolar epithelial injury repair, myofibroblast accumulation, and excessive collagen deposition are key pathologic features of idiopathic pulmonary fibrosis, eventually leading to cellular hypoxia and respiratory failure. The precise mechanism driving this complex maladaptive process remains inadequately understood. WD repeat and suppressor of cytokine signaling box containing 1 (WSB1) is an E3 ubiquitin ligase, the expression of which is associated strongly with hypoxia, and forms a positive feedback loop with hypoxia-inducible factor 1α (HIF-1α) under anoxic condition. This study explored the expression, cellular distribution, and function of WSB1 in bleomycin (BLM)-induced mouse lung injury and fibrosis. WSB1 expression was highly induced by BLM injury and correlated with the progression of lung fibrosis. Significantly, conditional deletion of Wsb1 in adult mice ameliorated BLM-induced pulmonary fibrosis. Phenotypically, Wsb1-deficient mice showed reduced lipofibroblast to myofibroblast transition, but enhanced alveolar type 2 proliferation and differentiation into alveolar type 1 after BLM injury. Proteomic analysis of mouse lung tissues identified caveolin 2 as a potential downstream target of WSB1, contributing to BLM-induced epithelial injury repair and fibrosis. These findings unravel a vital role for WSB1 induction in lung injury repair, thus highlighting it as a potential therapeutic target for pulmonary fibrosis.

Injury activated alveolar progenitors (IAAPs): the underdog of lung repair.

Alveolar epithelial type II cells (AT2s) together with AT1s constitute the epithelial lining of lung alveoli. In contrast to the large flat AT1s, AT2s are cuboidal and smaller. In addition to surfactant production, AT2s also serve as prime alveolar progenitors in homeostasis and play an important role during regeneration/repair. Based on different lineage tracing strategies in mice and single-cell transcriptomic analysis, recent reports highlight the heterogeneous nature of AT2s. These studies present compelling evidence for the presence of stable or transitory AT2 subpopulations with distinct marker expression, signaling pathway activation and functional properties. Despite demonstrated progenitor potentials of AT2s in maintaining homeostasis, through self-renewal and differentiation to AT1s, the exact identity, full progenitor potential and regulation of these progenitor cells, especially in the context of human diseases remain unclear. We recently identified a novel subset of AT2 progenitors named "Injury-Activated Alveolar Progenitors" (IAAPs), which express low levels of Sftpc, Sftpb, Sftpa1, Fgfr2b and Etv5, but are highly enriched for the expression of the surface receptor programmed cell death-ligand 1 (Pd-l1). IAAPs are quiescent during lung homeostasis but activated upon injury with the potential to proliferate and differentiate into AT2s. Significantly, a similar population of PD-L1 positive cells expressing intermediate levels of SFTPC are found to be expanded in human IPF lungs. We summarize here the current understanding of this newly discovered AT2 progenitor subpopulation and also try to reconcile the relationship between different AT2 stem cell subpopulations regarding their progenitor potential, regulation, and relevance to disease pathogenesis and therapeutic interventions.

miR-218-2 regulates cognitive functions in the hippocampus through complement component 3-dependent modulation of synaptic vesicle release.

microRNA-218 (miR-218) has been linked to several cognition related neurodegenerative and neuropsychiatric disorders. However, whether miR-218 plays a direct role in cognitive functions remains unknown. Here, using the miR-218 knockout (KO) mouse model and the sponge/overexpression approaches, we showed that miR-218-2 but not miR-218-1 could bidirectionally regulate the contextual and spatial memory in the mice. Furthermore, miR-218-2 deficiency induced deficits in the morphology and presynaptic neurotransmitter release in the hippocampus to impair the long term potentiation. Combining the RNA sequencing analysis and luciferase reporter assay, we identified complement component 3 (C3) as a main target gene of miR-218 in the hippocampus to regulate the presynaptic functions. Finally, we showed that restoring the C3 activity in the miR-218-2 KO mice could rescue the synaptic and learning deficits. Therefore, miR-218-2 played an important role in the cognitive functions of mice through C3, which can be a mechanism for the defective cognition of miR-218 related neuronal disorders.

Asymmetric Synthesis of Chiral 1,2-Bis(Boronic) Esters Featuring Acyclic, Non-Adjacent 1,3-Stereocenters.

The construction of acyclic, non-adjacent 1,3-stereogenic centers, prevalent motifs in drugs and bioactive molecules, has been a long-standing synthetic challenge due to acyclic nucleophiles being distant from the chiral environment. In this study, we successfully synthesized highly valuable 1,2-bis(boronic) esters featuring acyclic and nonadjacent 1,3-stereocenters. Notably, this reaction selectively produces migratory coupling products rather than alternative deborylative allylation or direct allylation byproducts. This approach introduces a new activation mode for selective transformations of gem-diborylmethane in asymmetric catalysis. Additionally, we found that other gem-diborylalkanes, previously challenging due to steric hindrance, also successfully participated in this reaction. The incorporation of 1,2-bis(boryl)alkenes facilitated the diversification of the alkenyl and two boron moieties in our target compounds, thereby enabling access to a broad array of versatile molecules. DFT calculations were performed to elucidate the reaction mechanism and shed light on the factors responsible for the observed excellent enantioselectivity and diastereoselectivity. These were determined to arise from ligand-substrate steric repulsions in the syn-addition transition state.

Palladium-Catalyzed Difunctionalization of Norbornenes via Arylation and Alkynylation.

We report the first general and practical method for the addition of aryl halides and alkynes to norbornenes with palladium catalysis. Norbornenes have been used as the unsaturated acceptors of aryl and alkynyl groups to construct saturated bridged C-C bonds. The combination of Pd(OAc)2/PCy3HBF4 has been identified as the optimal system promoting difunctionalization of norbornenes via the C-X/C-H bond cleavage and highly selective C(sp3)-C(sp2)/C(sp3)-C(sp) bond formation. Broad substrate scope and excellent functional group tolerance have been achieved to show the high efficiency of this approach. Mechanism studies based on experiments and DFT have been performed to gain insights into the catalytic mechanism.

FGFR2b signalling restricts lineage-flexible alveolar progenitors during mouse lung development and converges in mature alveolar type 2 cells.

The specification, characterization, and fate of alveolar type 1 and type 2 (AT1 and AT2) progenitors during embryonic lung development are poorly defined. Current models of distal epithelial lineage formation fail to capture the heterogeneity and dynamic contribution of progenitor pools present during early development. Furthermore, few studies explore the pathways involved in alveolar progenitor specification and fate. In this paper, we build upon our previously published work on the regulation of airway epithelial progenitors by fibroblast growth factor receptor 2b (FGFR2b) signalling during early (E12.5) and mid (E14.5) pseudoglandular stage lung development. Our results suggest that a significant proportion of AT2 and AT1 progenitors are lineage-flexible during late pseudoglandular stage development, and that lineage commitment is regulated in part by FGFR2b signalling. We have characterized a set of direct FGFR2b targets at E16.5 which are likely involved in alveolar lineage formation. These signature genes converge on a subpopulation of AT2 cells later in development and are downregulated in AT2 cells transitioning to the AT1 lineage during repair after injury in adults. Our findings highlight the extensive heterogeneity of pneumocytes by elucidating the role of FGFR2b signalling in these cells during early airway epithelial lineage formation, as well as during repair after injury.

Synaptotagmin-7 deficiency induces mania-like behavioral abnormalities through attenuating GluN2B activity.

Synaptotagmin-7 (Syt7) probably plays an important role in bipolar-like behavioral abnormalities in mice; however, the underlying mechanisms for this have remained elusive. Unlike antidepressants that cause mood overcorrection in bipolar depression, N-methyl-d-aspartate receptor (NMDAR)-targeted drugs show moderate clinical efficacy, for unexplained reasons. Here we identified Syt7 single nucleotide polymorphisms (SNPs) in patients with bipolar disorder and demonstrated that mice lacking Syt7 or expressing the SNPs showed GluN2B-NMDAR dysfunction, leading to antidepressant behavioral consequences and avoidance of overcorrection by NMDAR antagonists. In human induced pluripotent stem cell (iPSC)-derived and mouse hippocampal neurons, Syt7 and GluN2B-NMDARs were localized to the peripheral synaptic region, and Syt7 triggered multiple forms of glutamate release to efficiently activate the juxtaposed GluN2B-NMDARs. Thus, while Syt7 deficiency and SNPs induced GluN2B-NMDAR dysfunction in mice, patient iPSC-derived neurons showed Syt7 deficit-induced GluN2B-NMDAR hypoactivity that was rescued by Syt7 overexpression. Therefore, Syt7 deficits induced mania-like behaviors in mice by attenuating GluN2B activity, which enabled NMDAR antagonists to avoid mood overcorrection.

Ir-Catalyzed Enantioselective Synthesis of gem-Diborylalkenes Enabled by 1,2-Boron Shift.

Asymmetric cross-couplings based on 1,2-carbon migration from B-ate complexes have been developed efficiently to access valuable organoboronates. However, enantioselective reactions triggered by 1,2-boron shift have remained to be unaddressed synthetic challenge. Here, Ir-catalyzed asymmetric allylic alkylation enabled by 1,2-boron shift was developed. In this reaction, we disclosed that excellent enantioselectivities were achieved through an interesting dynamic kinetic resolution (DKR) process of allylic carbonates at the elevated temperature. Notably, the highly valuable (bis-boryl)alkenes have enabled an array of diversifications to access versatile molecules. Extensive experimental and computational studies were conducted to elucidate the reaction mechanism of DKR process and clarify the origin of excellent enantioselectivities.

FGF1 alleviates LPS-induced acute lung injury via suppression of inflammation and oxidative stress.

BACKGROUND: Acute lung injury (ALI) and its severe form, acute respiratory distress syndrome (ARDS), are devastating clinical disorders with high mortality, and for which more effective therapies are urgently needed. FGF1, the prototype member of the FGF family, is shown to exert protective effects against injurious stimuli in multiple disease models. Here we aimed to evaluate whether FGF1 pretreatment is protective against LPS-induced ALI and elucidate the potential underlying mechanisms. METHODS: For drug-treated groups, C57B/6 mice received a single i.p. injection of FGF1 (1 mg/kg) 1 h before the LPS challenge or not. To induce the ALI model, the mice were treated by intratracheal instillation of LPS (5 mg/kg). Then, histopathological changes in lung tissues were assessed by hematoxylin and eosin staining and transmission electron microscopy. ELISA and qPCR assays were used to detect pro-inflammatory cytokine levels in BALF and lung tissues, respectively. The total number of inflammatory cells (neutrophils and macrophages) in BALF were counted using the Wright-Giemsa method. The expressions of reactive oxygen species (ROS) and malondialdehyde (MDA) were measured using their respective kits. Western blot and immunostaining were used to evaluate the expressions of antioxidants (Nrf-2, HO-1, SOD2, GPX4, and Catalase), as well as the inflammatory and/or apoptosis-related factors (TLR4, NF-κB, and Cleaved- caspase 3). RESULTS: FGF1 pretreatment significantly ameliorated the LPS-induced histopathological changes, reduced lung wet/dry ratios, ROS and MDA levels, total BALF protein, inflammatory cell infiltration, proinflammatory cytokine levels, and significantly increased the expression of antioxidant proteins (Nrf-2, HO-1, Catalase, and SOD2). In addition, FGF1 pretreatment significantly reduced the expression of TLR4 and cleaved- caspase 3, inhibited NF-κB activation, and reduced LPS-induced cell apoptosis. CONCLUSIONS: Altogether, our results suggest that FGF1 pretreatment is protective against LPS-induced ALI through mediating anti-inflammatory and antioxidant effects, which may be attributed to the downregulation of TLR4 expression and inhibition of NF-κB activation, as well as promotion of antioxidant defenses. Therefore, FGF1 administration may prove beneficial in preventative strategies for ALI/ARDS.

Thiol Reactivity of N-Aryl α-Methylene-γ-lactams: Influence of the Guaianolide Structure.

The α-methylene-γ-lactam offers promise as a complementary warhead for the development of targeted covalent inhibitors. However, an understanding of the factors governing its electrophilic reactivity is needed to promote the development of lead compounds utilizing this motif. Herein we synthesize a series of N-aryl-substituted α-methylene-γ-lactams installed within the framework of a bioactive guaianolide analog. To determine the effects of the guaianolide structure on the electrophilic reactivity, these compounds were reacted with glutathione under biomimetic conditions, and the rate constants were measured. A linear free-energy relationship was observed with the Hammett parameter of the N-aryl group within the cis- or trans-annulated isomeric series of compounds. However, the trans-annulated compounds exhibited a ca. 10-fold increase in reactivity relative to both the cis-annulated compounds and the corresponding N-arylated 3-methylene-2-pyrrolidinones. Density functional theory calculations revealed that the reactivity of the trans-annulated stereoisomers is promoted by the partial release of the ring strain of the fused seven-membered ring in the thio-Michael addition transition state.

Bimetallic Cooperative Catalysis for Decarbonylative Heteroarylation of Carboxylic Acids via C-O/C-H Coupling.

Cooperative bimetallic catalysis is a fundamental approach in modern synthetic chemistry. We report bimetallic cooperative catalysis for the direct decarbonylative heteroarylation of ubiquitous carboxylic acids via acyl C-O/C-H coupling. This novel catalytic system exploits the cooperative action of a copper catalyst and a palladium catalyst in decarbonylation, which enables highly chemoselective synthesis of important heterobiaryl motifs through the coupling of carboxylic acids with heteroarenes in the absence of prefunctionalization or directing groups. This cooperative decarbonylative method uses common carboxylic acids and shows a remarkably broad substrate scope (>70 examples), including late-stage modification of pharmaceuticals and streamlined synthesis of bioactive agents. Extensive mechanistic and computational studies were conducted to gain insight into the mechanism of the reaction. The key step involves intersection of the two catalytic cycles via transmetallation of the copper-aryl species with the palladium(II) intermediate generated by oxidative addition/decarbonylation.

Time-resolved mRNA and miRNA expression profiling reveals crucial coregulation of molecular pathways involved in epithelial-pneumococcal interactions.

Streptococcus pneumoniae is a major causative agent of pneumonia worldwide and its complex interaction with the lung epithelium has not been thoroughly characterized. In this study, we exploited both RNA-sequencing and microRNA (miRNA)-sequencing approaches to monitor the transcriptional changes in human lung alveolar epithelial cells infected by S. pneumoniae in a time-resolved manner. A total of 1330 differentially expressed (DE) genes and 45 DE miRNAs were identified in all comparisons during the infection process. Clustering analysis showed that all DE genes were grouped into six clusters, several of which were primarily involved in inflammatory or immune responses. In addition, target gene enrichment analyses identified 11 transcription factors that were predicted to link at least one of four clusters, revealing transcriptional coregulation of multiple processes or pathways by common transcription factors. Notably, pharmacological treatment suggested that phosphorylation of p65 is important for optimal transcriptional regulation of target genes in epithelial cells exposed to pathogens. Furthermore, network-based clustering analysis separated the DE genes negatively regulated by DE miRNAs into two functional modules (M1 and M2), with an enrichment in immune responses and apoptotic signaling pathways for M1. Integrated network analyses of potential regulatory interactions in M1 revealed that multiple DE genes related to immunity and apoptosis were regulated by multiple miRNAs, indicating the coordinated regulation of multiple genes by multiple miRNAs. In conclusion, time-series expression profiling of messenger RNA and miRNA provides a wealth of information for global transcriptional changes, and offers comprehensive insight into the molecular mechanisms underlying host-pathogen interactions.

MicroRNA-133a alleviates airway remodeling in asthtama through PI3K/AKT/mTOR signaling pathway by targeting IGF1R.

Asthma is characterized by chronic inflammation, and long-term chronic inflammation leads to airway remodeling. But the potential regulatory mechanism of airway remodeling is not clearly understood, and there is still no effective way to prevent airway remodeling. Present studies have confirmed the role of microRNAs (miRNAs) in the development of disease, which is known as suppressing translation or degradation of messenger RNA (mRNA) at the posttranscriptional stage. In this study, we described the role of miRNA-133a in asthma and demonstrated it in regulating airway remodeling of asthma through the phosphoinositide 3 kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway by targeting IGF-1 receptor (IGF1R). IGF1R helps in mediating the intracellular signaling cascades. Asthmatic mice models were established by sensitization and Ovalbumin challenge. Adenovirus transfer vector carrying miR-133a or miR-133a sponge sequence was used to build the overexpression or downexpression of miR-133a modeling. Real-time polymerase chain reaction and Western blot were used to determine the alterations in the expression of miR-133a and mRNAs and their corresponding proteins. Results showed that miR-133a was downregulated in asthma. Upregulation of miR-133a expression in airway smooth muscle cells in vivo and in vitro could inhibit the activation of PI3K/AKT/mTOR pathway, and reduce the expression of α-smooth muscle actin (α-SMA), indicating that airway remodeling was inhibited. Functional studies based on luciferase reporter revealed miR-133a as a direct target of IGF1R mRNA. In conclusion, these data suggested that miR-133a regulated the expression of α-SMA through PI3K/AKT/mTOR signaling by targeting IGF1R. miR-133a plays a key role in airway remodeling of asthma and may serve as a potential therapeutic target for managing asthmatic airway remodeling.

Highly Chemoselective, Transition-Metal-Free Transamidation of Unactivated Amides and Direct Amidation of Alkyl Esters by N-C/O-C Cleavage.

The amide bond is one of the most fundamental functional groups in chemistry and biology and plays a central role in numerous processes harnessed to streamline the synthesis of key pharmaceutical and industrial molecules. Although the synthesis of amides is one of the most frequently performed reactions by academic and industrial scientists, the direct transamidation of tertiary amides is challenging due to unfavorable kinetic and thermodynamic contributions of the process. Herein, we report the first general, mild, and highly chemoselective method for transamidation of unactivated tertiary amides by a direct acyl N-C bond cleavage with non-nucleophilic amines. This operationally simple method is performed in the absence of transition metals and operates under unusually mild reaction conditions. In this context, we further describe the direct amidation of abundant alkyl esters to afford amide bonds with exquisite selectivity by acyl C-O bond cleavage. The utility of this process is showcased by a broad scope of the method, including various sensitive functional groups, late-stage modification, and the synthesis of drug molecules (>80 examples). Remarkable selectivity toward different functional groups and within different amide and ester electrophiles that is not feasible using existing methods was observed. Extensive experimental and computational studies were conducted to provide insight into the mechanism and the origins of high selectivity. We further present a series of guidelines to predict the reactivity of amides and esters in the synthesis of valuable amide bonds by this user-friendly process. In light of the importance of the amide bond in organic synthesis and major practical advantages of this method, the study opens up new opportunities in the synthesis of pivotal amide bonds in a broad range of chemical contexts.

Diagnosis and Treatment of Lambl's Excrescence on the Aortic Valve.

OBJECTIVE: Our objective is to summarize our experience in the diagnosis and treatment of Lambl's excrescence (LE) on the aortic valve. Methods: The clinical data of 25 patients with LE admitted to our hospital from January 2010 to December 2014 were analyzed retrospectively. There were 17 males and 8 females, with the mean age of 55.7 ± 11.43 years (range: 30 to 70 years). Among the patients analyzed, eight also had cerebral embolism. All of the patients were diagnosed by transesophageal echocardiography (TEE). In seven cases, surgical treatment to remove the excrescence was successfully performed. Results: All 25 patients were cured and discharged. There were no complications or operative mortalities in the seven patients that underwent surgical treatment. Follow-ups were performed for all patients for an average of 2.9 ± 1.5 years. During this time, none had a new cerebrovascular accident (CVA). Conclusions: Most patients with LE are asymptomatic, though some patients showed repeated episodes of stroke. We recommend TEE as the main diagnostic means of the disease. Patients with LE that have experienced two or more CVAs or combined other heart disease and need open heart surgery should be offered surgical excision of the excrescences. Other patients should be treated conservatively with anticoagulation, or monitored closely.

Computational Study of Mechanism and Thermodynamics of Ni/IPr-Catalyzed Amidation of Esters.

Nickel catalysis has shown remarkable potential in amide C⁻N bond activation and functionalization. Particularly for the transformation between ester and amide, nickel catalysis has realized both the forward (ester to amide) and reverse (amide to ester) reactions, allowing a powerful approach for the ester and amide synthesis. Based on density functional theory (DFT) calculations, we explored the mechanism and thermodynamics of Ni/IPr-catalyzed amidation with both aromatic and aliphatic esters. The reaction follows the general cross-coupling mechanism, involving sequential oxidative addition, proton transfer, and reductive elimination. The calculations indicated the reversible nature of amidation, which highlights the importance of reaction thermodynamics in related reaction designs. To shed light on the control of thermodynamics, we also investigated the thermodynamic free energy changes of amidation with a series of esters and amides.

Palladium-Catalyzed Decarbonylative Borylation of Carboxylic Acids: Tuning Reaction Selectivity by Computation.

Decarbonylative borylation of carboxylic acids is reported. Carbon electrophiles are generated directly after reagent-enabled decarbonylation of the in situ accessible sterically-hindered acyl derivative of a carboxylic acid under catalyst controlled conditions. The scope and the potential impact of this method are demonstrated in the selective borylation of a variety of aromatics (>50 examples). This strategy was used in the late-stage derivatization of pharmaceuticals and natural products. Computations reveal the mechanistic details of the unprecedented C-O bond activation of carboxylic acids. By circumventing the challenging decarboxylation, this strategy provides a general synthetic platform to access arylpalladium species for a wide array of bond formations from abundant carboxylic acids. The study shows a powerful combination of experiment and computation to predict decarbonylation selectivity.

Factors Controlling the Reactivity and Chemoselectivity of Resonance Destabilized Amides in Ni-Catalyzed Decarbonylative and Nondecarbonylative Suzuki-Miyaura Coupling.

N-Glutarimide amides have recently emerged as an exceptional group of compounds with unusually high reactivity in amide C-N bond activation. To understand the key factors that control the remarkable reactivity of these resonance destabilized amides, we explored the Ni-catalyzed decarbonylative and nondecarbonylative Suzuki-Miyaura coupling with N-glutarimide amides through density functional theory calculations. Two leading effects are responsible for the C-N cleavage activity of N-glutarimide amides, the coordinating N-substituents and the geometric twisting. The carbonyl substituent of the N-glutarimide amides provides crucial nickel-oxygen interaction, which essentially acts as a directing group to facilitate the formation of the reactive intermediate for the amide C-N bond cleavage. The geometric twisting weakens the resonance stability by removing the acyl-nitrogen conjugation, which lowers the energy penalty for the C-N bond stretch during oxidative addition. For the chemoselectivity of decarbonylation versus carbonyl retention, we found that the C-C reductive elimination for ketone formation is kinetically faster than that for biaryl formation, while ketone is thermodynamically less stable with respect to the decarbonylated biaryls. The computations also suggest that the nickel catalyst is able to promote the decarbonylation of biaryl ketones via an unexpected C-C bond activation.

Mechanism and Origins of Ligand-Controlled Stereoselectivity of Ni-Catalyzed Suzuki-Miyaura Coupling with Benzylic Esters: A Computational Study.

Nickel catalysts have shown unique ligand control of stereoselectivity in the Suzuki-Miyaura cross-coupling of boronates with benzylic pivalates and derivatives involving C(sp3)-O cleavage. The SIMes ligand (1,3-dimesityl-4,5-dihydroimidazol-2-ylidene) produces the stereochemically inverted C-C coupling product, while the tricyclohexylphosphine (PCy3) ligand delivers the retained stereochemistry. We have explored the mechanism and origins of the ligand-controlled stereoselectivity with density functional theory (DFT) calculations. The oxidative addition determines the stereoselectivity with two competing transition states, an SN2 back-side attack type transition state that inverts the benzylic stereogenic center and a concerted oxidative addition through a cyclic transition state, which provides stereoretention. The key difference between the two transition states is the substrate-nickel-ligand angle distortion; the ligand controls the selectivity by differentiating the ease of this angle distortion. For the PCy3 ligand, the nickel-ligand interaction involves mainly σ-donation, which does not require a significant energy penalty for the angle distortion. The facile angle distortion with PCy3 ligand allows the favorable cyclic oxidative addition transition state, leading to the stereoretention. For the SIMes ligand, the extra d-p back-donation from nickel to the coordinating carbene increases the rigidity of the nickel-ligand bond, and the corresponding angle distortion is more difficult. This makes the concerted cyclic oxidative addition unfavorable with SIMes ligand, and the back-side SN2-type oxidative addition delivers the stereoinversion.

Obesity and novel cardiovascular markers in a population without diabetes and cardiovascular disease in China.

OBJECTIVE: To investigate associations of novel cardiovascular markers with obesity in a general population. METHODS: A total of 9361 individuals without diabetes or cardiovascular disease were studied between 2009 and 2012 in China. High-sensitivity cardiac troponin T (hs-cTnT), N-terminal pro-B-type natriuretic peptide (NT-proBNP), brachial-ankle pulse wave velocity (baPWV), pulse pressure, and central systolic blood pressure (cSBP) were assessed according to body mass index (BMI) levels and different BMI/metabolic syndrome (MetS) combinations. RESULTS: 'Levels of hs-cTnT, baPWV, pulse pressure, and cSBP increased across BMI levels. Obesity was positively associated with these markers in multivariate models (P<0.05 for all). When stratified by MetS, these associations remained significant in the non-MetS group, and compared with normal weight participants, the obese participants had 1.87 (95% confidence interval: 1.48, 2.36), 1.27 (1.02, 1.57), 1.89 (1.39, 2.57), and 2.71 (2.11, 3.47) fold risks for having elevated hs-cTnT, baPWV, pulse pressure, and cSBP, respectively, and had 1.61 (1.26, 2.05), 1.75 (1.27, 2.42), 2.45 (1.46, 4.11), and 3.14 (2.13, 4.62) fold risks for having 1, 2, 3, and 4 elevated cardiovascular markers, respectively; while no relationship was observed between obesity and these novel markers in the MetS group, after multivariate adjustment. These results were unchanged when using a waist-hip ratio, body fat per cent, and visceral adiposity index to redefine obesity. CONCLUSIONS: Obesity was positively associated with novel cardiovascular markers (except NT-proBNP) in participants without MetS rather than in participants with MetS. Obese participants without MetS also had higher odds of having more number of elevated cardiovascular markers.