Efficient recruitment and angiogenesis of endothelial progenitor cells (EPCs) are critical during a thrombus event. However, the details of EPC recruitment and the regulation of angiogenesis have not ...been fully determined. The aim of this study was to determine the role of the long noncoding (lnc)RNA Wilms tumor 1 associated protein pseudogene 1 (WTAPP1) in regulation of the migration and angiogenesis of EPCs. EPCs were isolated from human peripheral blood and characterized by flow cytometry, after which lentivirus‐mediated lncRNA WTAPP1 overexpression and knockdown were performed. Scratch assay, Transwell assay, and in vitro and in vivo tube formation assays were performed to measure cell migration, invasion, and angiogenic abilities, respectively. Moreover, a microarray screen, bioinformatic prediction, and quantitative PCR and Western blot of miRNAs interacting with lncRNA WTAPP1 were conducted. Western blot was carried out to elucidate the relationship among WTAPP1, miR‐3120‐5P, and MMP‐1 in the autophagy pathway. WTAPP1 positively regulated migration, invasion, and in vitro and in vivo tube formation in EPCs by increasing MMP‐1 expression and activating PI3K/Akt/mTOR signaling. Furthermore, WTAPP1 contains a putative miR‐3120‐5P binding site. Suppression of WTAPP1 by miR‐3120‐5P decreased the level of MMP‐1. In addition, we demonstrated that suppression of the autophagy pathway is involved in the effects of WTAPP1 on EPC migration and angiogenesis. The lncRNA WTAPP1, a molecular decoy for miR‐3120‐5p, regulates MMP‐1 expression via the PI3K/Akt and autophagy pathways, thereby mediating cell migration and angiogenesis in EPCs. Acting as a potential therapeutic target, the lncRNA WTAPP1 may play an important role in the pathogenesis of DVT. Stem Cells 2018;36:1863–12
The long noncoding RNA Wilms tumor 1 associated protein pseudogene 1, a molecular decoy for miR‐3120‐5p, regulates MMP‐1 expression via the PI3K/Akt and autophagy pathways, thereby mediating cell migration and angiogenesis in endothelial progenitor cells.
Hypoxia occurs naturally at high-altitudes and pathologically in hypoxic solid tumors. Here, we report that genes involved in various human cancers evolved rapidly in Tibetans and six Tibetan ...domestic mammals compared to reciprocal lowlanders. Furthermore, m
A modified mRNA binding protein YTHDF1, one of evolutionary positively selected genes for high-altitude adaptation is amplified in various cancers, including non-small cell lung cancer (NSCLC). We show that YTHDF1 deficiency inhibits NSCLC cell proliferation and xenograft tumor formation through regulating the translational efficiency of CDK2, CDK4, and cyclin D1, and that YTHDF1 depletion restrains de novo lung adenocarcinomas (ADC) progression. However, we observe that YTHDF1 high expression correlates with better clinical outcome, with its depletion rendering cancerous cells resistant to cisplatin (DDP) treatment. Mechanistic studies identified the Keap1-Nrf2-AKR1C1 axis as the downstream mediator of YTHDF1. Together, these findings highlight the critical role of YTHDF1 in both hypoxia adaptation and pathogenesis of NSCLC.
In order to study the flow behaviors of an Al-Zn-Mg-Cu alloy at elevated temperatures, uniaxial tensile tests were carried out in wide deformation temperature and strain rate ranges. The flow stress ...rapidly increases to a peak value and then slightly decreases with the increased strain, and the dynamic recovery (DRV) is the primary softening mechanism. A unified constitutive model based on dislocation density was developed. An iterative procedure was implemented into the developed model to describe the flow behaviors at time-variant deformation conditions (e.g. the strain rate is changed during hot deformation). The predicted flow stresses were in accord with the experimental results, suggesting that the flow behaviors of the studied Al alloy at elevated temperatures can be well reproduced by the developed model. Meanwhile, the variations of the product of the instantaneous work hardening (WH) rate and stress caused by dislocation evolution, the dislocation density changing rate, as well as the dislocation mean free path, were given to analyze the WH and DRV mechanisms of Al-Zn-Mg-Cu alloy.
C1q/tumor necrosis factor (TNF)-related protein 12 (CTRP12) is a secretory protein that participates in the regulation of glucose and lipid metabolism in obesity and diabetes. Its role in ...cardiovascular disease, particularly sepsis-induced cardiac injury, is unclear. Here, we stimulated cardiomyocytes with lipopolysaccharide (LPS) to establish an in vitro cardiomyocyte injury model and CTRP12 was overexpressed with an adenovirus delivery system. Overexpression of CTRP12 reduced the transcription and release of pro-inflammatory cytokines from LPS-stimulated cardiomyocytes, including TNFα, interleukin-1 (IL-1), and IL-6. Reactive oxygen species (ROS) level increased and the oxidation/redox system was disturbed in LPS-stimulated cardiomyocytes, as evident from the decrease in superoxide dismutase activity and an increase in reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity and malondialdehyde level. CTRP12 overexpression decreased the increasing level of ROS and ameliorated the unbalance in the oxidation/redox system in LPS-stimulated cardiomyocytes. The viability of cardiomyocytes decreased after LPS stimulation, and the cells underwent apoptosis. CTRP12-overexpressing cardiomyocytes showed a decrease in the number of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL)-positive cells, and the ratio of B cell lymphoma (Bcl)-1/Bax in these cells was recovered. In comparison with the control group, LPS-stimulated cardiomyocytes showed reduced expression of nuclear factor E2-related factor 2 (NRF2), while CTRP12-overexpressing cardiomyocytes showed elevated NRF2 expression. Small-interfering RNA-mediated silencing of NRF2 expression in cardiomyocytes resulted in the inhibition of the protective effects of CTRP12. Thus, CTRP12 ameliorated injury in LPS-stimulated cardiomyocytes in an NRF2-dependent manner.
Two‐dimensional (2D) materials and ultrathin nanosheets are advantageous for elevating the catalysis performance and elucidating the catalysis mechanism of heterogeneous catalysts, but they are ...mostly restricted to inorganic or organic materials based on covalent bonds. We report an electrochemical/chemical exfoliation strategy for synthesizing metal–organic 2D materials based on coordination bonds. A catechol functionalized ligand is used as the redox active pillar to construct a pillared‐layer framework. When the 3D pillared‐layer MOF serves as an electrocatalyst for water oxidation (pH 13), the pillar ligands can be oxidized in situ and removed. The remaining ultrathin (2 nm) nanosheets of the metal–organic layers are an efficient catalyst with overpotentials as low as 211 mV at 10 mA cm−2 and a turnover frequency as high as 30 s−1 at an overpotential of 300 mV.
MOF slicing: A pillared‐layer metal–organic framework (MOF), in which the catechol functionalized pillars can be oxidized and removed in an electrochemical process, gives ultrathin nanosheets (2 nm). These are efficient electrocatalysts for water oxidation at pH 13 with a low overpotential and high turnover frequency (TOF).
Cu‐based metal–organic frameworks have attracted much attention for electrocatalytic CO2 reduction, but they are generally instable and difficult to control the product selectivity. We report ...flexible Cu(I) triazolate frameworks as efficient, stable, and tunable electrocatalysts for CO2 reduction to C2H4/CH4. By changing the size of ligand side groups, the C2H4/CH4 selectivity ratio can be gradually tuned and inversed from 11.8 : 1 to 1 : 2.6, giving C2H4, CH4, and hydrocarbon selectivities up to 51 %, 56 %, and 77 %, respectively. After long‐term electrocatalysis, they can retain the structures/morphologies without formation of Cu‐based inorganic species. Computational simulations showed that the coordination geometry of Cu(I) changed from triangular to tetrahedral to bind the reaction intermediates, and two adjacent Cu(I) cooperated for C−C coupling to form C2H4. Importantly, the ligand side groups controlled the catalyst flexibility by the steric hindrance mechanism, and the C2H4 pathway is more sensitive than the CH4 one.
Flexible Cu(I) triazolate frameworks functionalized with dinuclear copper sites can serve as highly stable and efficient electrocatalysts for CO2 reduction to C2H4/CH4, and the selectivity is tunable by the size of uncoordinated ligand side groups.
The ethanol/water separation challenge highlights the adsorption capacity/selectivity trade‐off problem. We show that the target guest can serve as a gating component of the host to block the ...undesired guest, giving molecular sieving effect for the adsorbent possessing large pores. Two hydrophilic/water‐stable metal azolate frameworks were designed to compare the effects of gating and pore‐opening flexibility. Large amounts (up to 28.7 mmol g−1) of ethanol with fuel‐grade (99.5 %+) and even higher purities (99.9999 %+) can be produced in a single adsorption process from not only 95 : 5 but also 10 : 90 ethanol/water mixtures. More interestingly, the pore‐opening adsorbent possessing large pore apertures showed not only high water adsorption capacity but also exceptionally high water/ethanol selectivity characteristic of molecular sieving. Computational simulations demonstrated the critical role of guest‐anchoring aperture for the guest‐dominated gating process.
As demonstrated by the extraordinary ethanol purification performances of a pore‐opening adsorbent for various ethanol/water mixtures, the guest‐dominated gating process, in which the preferentially‐adsorbed guest serves as the gating component, is critical for achieving ultrahigh adsorption selectivity in large‐pore adsorbents and avoiding the co‐adsorption problem of pore‐opening adsorbents.
Efficient adsorptive separation of propylene/propane (C3H6/C3H8) is highly desired and challenging. Known strategies focus on either the thermodynamic or the kinetic mechanism. Here, we report an ...interesting reactivity of a metal–organic framework that improves thermodynamic and kinetic adsorption selectivity simultaneously. When the metal–organic framework is heated under oxygen flow, half of the soft methylene bridges of the organic ligands are selectively oxidized to form the more polar and rigid carbonyl bridges. Mixture breakthrough experiments showed drastic increase of C3H6/C3H8 selectivity from 1.5 to 15. For comparison, the C3H6/C3H8 selectivities of the best‐performing metal–organic frameworks Co‐MOF‐74 and KAUST‐7 were experimentally determined to be 6.5 and 12, respectively. Gas adsorption isotherms/kinetics, single‐crystal X‐ray diffraction, and computational simulations revealed that the oxidation gives additional guest recognition sites, which improve thermodynamic selectivity, and reduces the framework flexibility, which generate kinetic selectivity.
Tailoring with O2: When a flexible metal–organic framework is heated in a flow of oxygen, half of the organic ligands are selectively oxidized, thereby adding guest recognition sites and reducing the flexibility of the pores. As a result, the thermodynamic and kinetic selectivity for propylene/propane separation improve simultaneously.
Summary
Cutaneous wounds are among the most common soft tissue injuries and are particularly hard to heal in aging. Caloric restriction (CR) is well documented to extend longevity; pharmacologically, ...profound rejuvenative effects of CR mimetics have been uncovered, especially metformin (MET), resveratrol (RSV), and rapamycin (RAPA). However, locally applied impacts and functional differences of these agents on wound healing remain to be established. Here, we discovered that chronic topical administration of MET and RSV, but not RAPA, accelerated wound healing with improved epidermis, hair follicles, and collagen deposition in young rodents, and MET exerted more profound effects. Furthermore, locally applied MET and RSV improved vascularization of the wound beds, which were attributed to stimulation of adenosine monophosphate‐activated protein kinase (AMPK) pathway, the key mediator of wound healing. Notably, in aged skin, AMPK pathway was inhibited, correlated with impaired vasculature and reduced healing ability. As therapeutic approaches, local treatments of MET and RSV prevented age‐related AMPK suppression and angiogenic inhibition in wound beds. Moreover, in aged rats, rejuvenative effects of topically applied MET and RSV on cell viability of wound beds were confirmed, of which MET showed more prominent anti‐aging effects. We further verified that only MET promoted wound healing and cutaneous integrity in aged skin. These findings clarified differential effects of CR‐based anti‐aging pharmacology in wound healing, identified critical angiogenic and rejuvenative mechanisms through AMPK pathway in both young and aged skin, and unraveled chronic local application of MET as the optimal and promising regenerative agent in treating cutaneous wound defects.
Cobalt imidazolate frameworks are classical electrocatalysts for the oxygen evolution reaction (OER) but suffer from the relatively low activity. Here, a non‐3d metal modulation strategy is presented ...for enhancing the OER activity of cobalt imidazolate frameworks. Two isomorphous frameworks Co4(MO4)(eim)6 (M=Mo or W, Heim=2‐ethylimidazole) having Co(eim)3(MO4) units and high water stabilities were designed and synthesized. In different neutral media, the Mo‐modulated framework coated on a glassy carbon electrode shows the best OER performances (1 mA cm−2 at an overpotential of 210 mV in CO2‐saturated 0.5 m KHCO3 electrolyte and 2/10/22 mA cm−2 at overpotential of 388/490/570 mV in phosphate buffer solution) among non‐precious metal catalysts and even outperforms RuO2. Spectroscopic measurements and computational simulations revealed that the non‐3d metals modulate the electronic structure of Co for optimum reactant/product adsorption and tailor the energy of rate‐determining step to a more moderate value.
Non‐3D for 3D: Introducing non‐3d metal oxide units into a cobalt imidazolate framework results in the drastic enhancement of electrocatalytic performance of the oxygen evolution reaction in neutral media.
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