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MicroRNAs, a class of small and non-encoding RNAs that transcriptionally or post-transcriptionally modulate the expression of their target genes, has been implicated as critical regulatory molecules in many cardiovascular diseases, including ischemia/reperfusion induced cardiac injury. Here, we report microRNA-145, a tumor suppressor miRNA, can protect cardiomyocytes from hydrogen peroxide (H2O2)-induced apoptosis through targeting the mitochondrial pathway. Quantitative real-time PCR (qPCR) demonstrated that the expression of miR-145 in either ischemia/reperfused mice myocardial tissues or H2O2-treated neonatal rat ventricle myocytes (NRVMs) was markedly down-regulated. Over-expression of miR-145 significantly inhibited the H2O2-induced cellular apoptosis, ROS production, mitochondrial structure disruption as well as the activation of key signaling proteins in mitochondrial apoptotic pathway. These protective effects of miR-145 were abrogated by over-expression of Bnip3, an initiation factor of the mitochondrial apoptotic pathway in cardiomyocytes. Finally, we utilized both luciferase reporter assay and western blot analysis to identify Bnip3 as a direct target of miR-145. Our results suggest miR-145 plays an important role in regulating mitochondrial apoptotic pathway in heart challenged with oxidative stress. MiR-145 may represent a potential therapeutic target for treatment of oxidative stress-associated cardiovascular diseases, such as myocardial ischemia/reperfusion injury.

The versatility of perovskite crystal structure has become the great advantage of lead halide perovskite nanocrystals (NCs) during their functional applications. Here we report an effective solvothermal method for the controllable synthesis of CsPbBr3 nanoplatelets (NPLs) and their transformation to Cs4PbBr6 NCs. Through solvothermal reaction of a mixture of Cs-oleate and PbBr2 precursors, CsPbBr3 NPLs can be synthesized in mass production. The lateral sizes of CsPbBr3 NPLs can be precisely tuned by varying the solvothermal reaction temperatures and times, while the thickness of NPLs remains constant at ∼4.2 nm, which is in the quantum confinement regime. The fine-tuning of lateral NPL sizes results in precise modulation of their photoluminescence emission. Moreover, an interesting phase transformation from cubic CsPbBr3 NPLs to rhombohedral Cs4PbBr6 NCs, and the reversible transformation from Cs4PbBr6 NCs to CsPbBr3 NPLs can be readily achieved by changing the solvothermal reaction sources. The present solvothermal approach is simple, convenient, controllable, and can be easily extended to preparation of other perovskite NCs with different halide compositions.

Due to the high electron charge, large ion radius, and plentiful outer hybrid orbitals of Ln III cations, microporous Ln-MOFs can be used as Lewis acidic catalysts with high catalytic activity for a variety of organic reactions, which prompts us to explore cluster-based nanoporous Ln-MOFs by employing structure-oriented ligands. Herein, the exquisite combination of coplanar [Ln 4 (μ 3 −OH) 2 (μ 2 −HCO 2 )(H 2 O) 2 ] clusters (abbreviated as {Ln 4 }) and the structure-oriented multifunctional ligand ofTo the best of our knowledge, NUC-38Ho and NUC-38Yb are rarely reported {Ln 4 }-based three-dimensional (3D) frameworks with embedded hierarchical triangular-microporous and hexagonal-nanoporous channels, which are shaped by six rows of coplanar {Ln 4 } clusters and characterized by plentiful coexisting Lewis acid−base sites on the inner wall including open Ln III sites, N pyridine atoms, μ 3 −OH, and μ 2 −HCO 2 . Catalytic experiments performed using NUC-38Yb as the representative exhibited that NUC-38Yb possessed a high catalytic activity on the cycloaddition reactions of epoxides with CO 2 under mild conditions, which can be ascribed to its structural advantages including nanoscale channels, rich bifunctional active sites, large surface areas, and chemical stability. Moreover, NUC-38Yb, as a heterogeneous catalyst, could greatly accelerate the Knoevenagel condensation reactions of aldehydes and malononitrile. Hence, this work paves the way for the construction of functional Ln-cluster-based nanoporous metal−organic frameworks (MOFs) by elaborately designing functional ligands with transnormal connection modes.