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Co3O4-based anodes are challenged by low rate capability and poor cycling stability, arising from the inherent structural instability of the electrode alongside difficulties for electrolyte penetration within the electrode interior. A potential solution to address this obstacle is through the meticulous design of electrode architecture. With this in mind, ultrathin nanosheets adorned with finely honeycomb-like Co3O4 porous balls featuring cavities were synthesized via in situ incorporation of a Co2+ source and SiO2 precursor solution. The Co3O4 porous balls, with a honeycomb-like structure, yielded a consistent discharge capacity of 727 mA h g−1 at 0.5 A g−1 over 230 cycles, and an impressive 540 mA h g−1 at 2 A g−1 over 500 cycles, indicative of remarkable rate capabilities. This exceptional electrochemical performance is credited to the distinctive porous honeycomb-like structure and cavities among the balls. This structure acts as a buffer against volume change during charge–discharge processes, guaranteeing a well-maintained electrode structure and providing strong cycling stability. Furthermore, these ultrathin and intricately porous nanosheets minimize the transport distance of ions and charges, facilitating access to more active sites. These notable features have the ability to augment rate performance and lithium storage capabilities. [ABSTRACT FROM AUTHOR]

Background: Sporadic aortic aneurysm and dissection (AAD) is a critical condition characterised by the progressive loss of vascular smooth muscle cells (VSMCs) and the breakdown of the extracellular matrix. However, the molecular mechanisms responsible for the phenotypic switch and loss of VSMCs in AAD are not fully understood., Methods and Results: In this study, we employed a discovery-driven, unbiased approach. This approach encourages us to explore the unknown functions of activating transcription factor 3 (ATF3) rather than merely confirming existing hypotheses, while no assumptions were made about ATF3 prior to the experiments. We ensured the unbiased nature of our assessment by conducting morphological evaluations with two independent observers in a blinded manner. We identified elevated expression of ATF3 in both human sporadic AAD tissues and mouse AAD models. VSMC-specific ATF3 conditional knockout (Atf3 cKO) mice showed notable enlargement, dissection and rupture in both thoracic and abdominal aortic regions after exposure to Ang II. Interestingly, older Atf3 cKO mice exhibited spontaneous aortic dissections and senescence of the aortic wall. Mechanistically, ATF3 deficiency led to the degradation of P21 through ubiquitination. Impaired DNA repair in VSMCs resulted in micronuclei formation in the cytoplasm, activating the  cyclicGMP-AMP synthase- stimulator of interferon genes (cGAS-STING) pathway and inducing VSMC phenotypic switching and apoptosis. Finally, both pharmacological complementation of P21 function and knockdown of STING expression alleviated ATF3 deficiency-induced AAD., Conclusions: Our study indicates that ATF3 is essential for genomic DNA stability in VSMCs through the P21-cGAS-STING pathway, suggesting that enhancing ATF3 expression in VSMCs could help prevent sporadic AAD., Key Points: ATF3 deficiency led to degradation of P21 through ubiquitination, which abolished the G1 phase arrest. VSMCs had no time window to repair the damaged DNA, leading to generation of micronuclei in cytoplasm. Cytoplasmic micronuclei facilitating the activation of cGAS-STING pathway, thus inducing the phenotypic switch and apoptosis of VSMCs., (© 2024 The Author(s). Clinical and Translational Medicine published by John Wiley & Sons Australia, Ltd on behalf of Shanghai Institute of Clinical Bioinformatics.)

Our previous study finds that exosomal microRNA (miR)-186-5p promotes viability and invasion of vascular smooth muscle cells to accelerate atherosclerosis via inactivating phosphoinositide 3 kinase/protein kinase B/mammalian target of rapamycin pathway. Subsequently, this study aimed to identify the linkage of serum exosomal miR-186-5p with clinical features and major adverse cardiovascular events (MACE) in coronary heart disease (CHD) patients. Serum exosomal miR-186-5p was quantified in 175 CHD patients and 50 healthy controls (HCs) via reverse transcription quantitative polymerase chain reaction. Our study revealed that serum exosomal miR-186-5p was enhanced in CHD patients vs. HCs (P < 0.001). In CHD patients, serum exosomal miR-186-5p was positively correlated with total cholesterol (P = 0.002) and low-density lipoprotein cholesterol (P = 0.003). Elevated serum exosomal miR-186-5p was linked with increased Gensini score (P = 0.028) and stenosis degree categorized by the Gensini score (P = 0.018). Regarding MACE, the 1-year and 2-year accumulating MACE rate was 6.6% and 15.6%, respectively. Serum exosomal miR-186-5p was elevated in CHD patients with MACE vs. those without (P = 0.042). By Kaplan-Meier curves and log-rank analyses, serum exosomal miR-186-5p > 1.000 (P = 0.404) and > 1.610 (P = 0.328) was not related to accumulating MACE. While serum exosomal miR-186-5p > 3.390 exhibited a correlative trend with increased accumulating MACE, but not achieving statistical significance (P = 0.071). The 1-year and 2-year accumulating MACE rate of patients with serum exosomal miR-186-5p > 3.390 was 11.5% and 21.5%, respectively; while the rate was 3.3% and 11.5% in patients with serum exosomal miR-186-5p ≤ 3.390, accordingly. Conclusively, serum exosomal miR-186-5p positively associates with lipid level, coronary stenosis degree, and the risk of MACE in CHD patients.

Our previous study revealed oxidized-low density lipoprotein (oxLDL)-stimulated macrophages delivered exosomes to exacerbate vascular smooth muscle cell (VSMC) viability and invasion; and microRNA-320b was enriched in exosomes from oxLDL-stimulated macrophages. This study aimed to further explore molecular mechanisms of exosomal microRNA-320b from oxLDL-stimulated macrophages on cellular functions of VSMCs. Exosomes from oxLDL-stimulated macrophages with microRNA-320b mimic/inhibitor transfection were used to treat VSMCs. Next, microRNA-320b mimic/inhibitor, and microRNA-320b mimic with or without peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PPARGC1A) overexpression vector were transfected into VSMCs. Viability, invasion, apoptosis, contractile/synthetic phenotype markers, and MEK/ERK pathway were detected in VSMCs. Exosomes from microRNA-320b mimic-treated macrophages promoted viability, invasion, and synthetic phenotype marker osteopontin, while suppressed apoptosis and contractile phenotype marker α-smooth muscle actin in VSMCs. Importantly, direct microRNA-320b mimic treatment aggravated viability, invasion, and synthetic phenotype transition in VSMCs. However, microRNA-320b inhibitor showed the opposite effects as microRNA-320b mimic. Next, luciferase reporter gene assay showed that microRNA-320b directly bound to PPARGC1A; microRNA-320b also inversely regulated PPARGC1A in VSMCs. Moreover, the effect of microRNA-320b mimic on cellular functions of VSMCs was hampered by PPARGC1A overexpression vector (all P < 0.05). Additionally, microRNA-320b activated MEK/ERKT pathway, which was also suppressed by PPARGC1A overexpression vector (all P < 0.05). OxLDL-stimulated macrophages deliver exosomal microRNA-320b to exacerbate viability, invasion, and synthetic phenotype transition in VSMCs via modulating PPARGC1A-mediated MEK/ERK pathway, thus participating in the progression of atherosclerosis.