Zika virus (ZIKV) is a re-emerging flavivirus that leads to devastating consequences for fetal development. It is crucial to visualize the pathogenicity activities of ZIKV ranging from infection pathways to immunity processes, but the accurate labeling of ZIKV remains challenging due to the lack of a reliable labeling technique. We introduce the photo-activated bio-orthogonal cycloaddition to construct a fluorogenic probe for the labeling and visualizing of ZIKV. Via a simple UV photoirradiation, the fluorogenic probes could be effectively labeled on the ZIKV. We demonstrated that it can be used for investigating the interaction between ZIKV and diverse cells and avoiding the autofluorescence phenomenon in traditional immunofluorescence assay. Thus, this bioorthogonal-enabled labeling strategy can serve as a promising approach to monitor and understand the interaction between the ZIKV and host cells.

Infectious wound healing remains a significant medical challenge due to chronic inflammation and bacterial colonization. Effective antimicrobial and anti-inflammatory therapies are essential to facilitate wound recovery. Herein, we introduce a highly biocompatible, ROS-responsive DNA hydrogel (LGAH), modified with aggregation-induced emission luminogens (AIEgen) and incorporating ginseng-derived exosomes (G-Exos) and nitric oxide (NO) donor-L-arginine (L-Arg) to promote healing of infected wounds. The hydrogel degrades in response to elevated ROS levels, releasing therapeutic agents. Upon laser irradiation, AIEgen generates ¹O₂, which activates L-Arg to produce NO, leading to a synergistic antimicrobial effect. NO is particularly effective at inhibiting bacterial growth and promoting angiogenesis, supporting wound healing. G-Exos modulate immune responses, reduce inflammation, and promote the transition from the inflammatory to the proliferative phase. They also enhance cell proliferation, migration, and collagen production, which are key to tissue regeneration. In vivo experiments demonstrated that LGAH significantly accelerates S. aureus-infected wound healing by modulating the wound microenvironment and promoting tissue regeneration. Transcriptomic analysis revealed that LGAH down-regulates gene expression in inflammation and immune response signaling pathways while up-regulating genes related to energy metabolism. Biosafety evaluations at cellular and animal levels have demonstrated that LGAH possesses excellent biocompatibility and biodegradability, making it ideal for tissue repair and regeneration. This multifunctional DNA hydrogel system offers a safe and promising strategy for the clinical treatment of infected wounds.

Hyperhomocysteinemia (HHcy), which is an independent risk factor for atherosclerosis, might cause dysregulation of gene expression, but the character

Elevated homocysteine (Hcy) levels have been reported to be involved in liver injury, and autophagy plays an important role in normal hepatic physiology and pathophysiology, but the mechanism underlying Hcy regulated autophagy is currently unknown. In this study, CBS^+/- mice were fed with regular diet for 12 weeks to establish a hyperhomocysteinemia (HHcy) model and HL-7702 cells were treated with Hcy, we found that Hcy increases autophagy and aggravates liver injury by downregulation of cystic fibrosis transmembrane conductance regulator (CFTR) expression in vivo and in vitro. Overexpression of CFTR inhibited the formation of autophagosomes and the expression of autophagy-related proteins BECN1, LC3-II/I and Atg12, while the expression of p62 increased in Hcy-treated hepatocytes and CBS^+/- mice injected with lentivirus expressing CFTR. Further study showed that CFTR expression is regulated by the interaction of DNA methyltransferase 1 (DNMT1) and enhancer of zeste homolog 2 (EZH2), which, respectively, regulate DNA methylation and histone H3 lysine 27 trimethylation (H3K27me3). In conclusion, our study showed that Hcy activates autophagy by inhibition of CFTR expression via interaction between H3K27me3 and DNA methylation in the mouse liver. These findings provide new insight into the mechanism of Hcy-induced autophagy in liver injury.

It is well‐established that homocysteine (Hcy) is an independent risk factor for atherosclerosis. Hcy can promote vascular smooth muscle cell (VSMC) proliferation, it plays a key role in neointimal formation and thus contribute to arteriosclerosis. However, the molecular mechanism on VSMCs proliferation underlying atherosclerosis is not well elucidated. Mitofusin‐2 (MFN2) is an important transmembrane GTPase in the mitochondrial outer membrane and it can block cells in the G0/G1 stage of the cell cycle. To investigate the contribution of aberrant MFN2 transcription in Hcy‐induced VSMCs proliferation and the underlying mechanisms. Cell cycle analysis revealed a decreased proportion of VSMCs in G0/G1 and an increased proportion in S phase in atherosclerotic plaque of APOE^−/− mice with hyperhomocystinaemia (HHcy) as well as in VSMCs exposed to Hcy in vitro. The DNA methylation level of MFN2 promoter was obviously increased in VSMCs treated with Hcy, leading to suppressed promoter activity and low expression of MFN2. In addition, we found that the expression of c‐Myc was increased in atherosclerotic plaque and VSMCs treated with Hcy. Further study showed that c‐Myc indirectly regulates MFN2 expression is duo to the binding of c‐Myc to DNMT1 promoter up‐regulates DNMT1 expression leading to DNA hypermethylation of MFN2 promoter, thereby inhibits MFN2 expression in VSMCs treated with Hcy. In conclusion, our study demonstrated that Hcy‐induced hypermethylation of MFN2 promoter inhibits the transcription of MFN2, leading to VSMCs proliferation in plaque formation, and the increased binding of c‐Myc to DNMT1 promoter is a new and relevant molecular mechanism.