Role of FOXM1 in vascular smooth muscle cell survival and neointima formation following vascular injury

Vascular restenosis following paclitaxel-coated balloon therapy is attributable to NLRP3 activation and LIN9 upregulation

Lower limb arterial occlusive disease is treated with intraluminal devices, such as paclitaxel (PTX)-coated balloons (PCBs); however, post-procedural restenosis remains a significant challenge. NLRP3 activation is known to play a significant role in atherosclerosis, but its involvement in restenosis following PCB intervention remains to be investigated. We identified that NLRP3 was differentially expressed in lower-limb arterial tissues sourced from healthy controls and patients with arterial occlusive disease. Through cell experiments, we confirmed that PTX is involved in the activation of NLRP3. Subsequently, we demonstrated that NLRP3 activation promotes the proliferation and migration of vascular smooth muscle cell (VSMC), thereby reducing their sensitivity to PTX. NLRP3 activation also stimulates the secretion of the inflammatory cytokine interleukin IL-1β. RNA sequencing of IL-1β-treated VSMC revealed the upregulation of BRD4 and LIN9. Further mechanistic investigations confirmed that IL-1β facilitates BRD4 recruitment, leading to enhanced LIN9 expression. The transcription factor LIN9 binds to the promoter region of the cell-cycle regulator AURKA, thereby promoting its transcription and subsequently upregulating the expression of the cell proliferation-associated molecule FOXM1. These processes ultimately mediate the proliferation, migration, and PTX resistance of VSMC. Additionally, we discovered that JQ1 inhibited the overexpression of the above molecules, and exhibited a synergistic effect with PTX. Our conclusions were validated through in vivo experiments in Sprague-Dawley rats. Collectively, our findings provide insights into the molecular mechanisms underlying restenosis following PCB therapy, and suggest that the combined use of JQ1 and PTX devices may represent a promising therapeutic strategy.

Corilagin ameliorates macrophages inflammation in atherosclerosis through TLR4-NFκB/MAPK pathway

Corilagin, a polyphenolic tannic acid compound, showed significant anti-inflammatory activity in atherosclerotic mice. The present study aimed to evaluate the effect and mechanism of corilagin in atherosclerosis by in vivo, in vitro and in molecular docking strategies analysis. An atherosclerotic model was established by feeding ApoE-/- mice a high-fat diet. Murine RAW264.7 macrophages were cultured and induced with lipopolysaccharide (LPS). Treatment with corilagin had a marked inhibitory effect on the plaque area and lipid accumulation in atherosclerotic mice. Corilagin decreased the expression of iNOS and promoted the expression of CD206 in aortic plaque, as well as inhibited the production of proinflammatory factors in HFD-fed ApoE-/- mice and LPS-induced RAW264.6 cell. Corilagin also obviously inhibited the expression of TLR4, reduced the phosphorylation of the JNK, the protein expressions of p38 and NF-κB pathway. In addition, corilagin markedly diminished the nuclear translocation of NF-κBp65. Similarly, molecular docking study suggested that hydrogen bonds were detected between the corilagin and the five proteins (TLR4, Myd88, p65, P38, and JNK) with a significant "CDOCKER energy". These results showed that the antiatherosclerotic effect of corilagin against M1 macrophage polarization and inflammation via suppression the activation of TLR4-NFκB/MAPK signaling pathway. Therefore, corilagin could be a promising lead compound to develop drugs for the treatment of atherosclerosis.

Stimulus-Responsive Zwitterionic Prodrug Delivery System with Sustained Release of Hydrogen Sulfide for Protective Aortic Dissection

Aortic dissection (AD) is one of the most frequent types of aortic disease with extremely poor prognosis. The biological signaling gas hydrogen sulfide (H2S) has exhibited protective effects in various types of cardiovascular diseases. However, as a toxic, colorless gas, the application of H2S is immensely hampered due to the lack of ideal donors. In this article, a drug delivery system with a H2S donor has been prepared. Meanwhile, the donor could be deposed in a cysteine-containing environment to generate H2S. The results indicate that the H2S donor polymer nanomicelles mitigated the processive transformation of smooth muscle cells effectively in a proper concentration range, which may play a protective role in aortic dissection. In animal experiments, the sustained-release H2S donor stimulated in the presence of cysteine was found to demonstrate beneficial effects in a murine model of aortic dissection and would likely become a potential target of H2S therapy for cardiovascular diseases.

MKL1 fuels ROS-induced proliferation of vascular smooth muscle cells by modulating FOXM1 transcription

Reactive oxygen species (ROS) promotes vascular injury and neointima formation in part by stimulating proliferation of vascular smooth muscle cells (VSMC). The underlying transcriptional mechanism, however, is not completely understood. Here we report that VSMC-specific deletion of MKL1 in mice suppressed neointima formation in a classic model of vascular injury. Likewise, pharmaceutical inhibition of MKL1 activity by CCG-1423 similarly mollified neointima formation in mice. Over-expression of a constitutively active MKL1 in vascular smooth muscle cells enhanced proliferation in a ROS-dependent manner. On the contrary, MKL1 depletion or inhibition attenuated VSMC proliferation. PCR array based screening identified forkhead box protein M1 (FOXM1) as a direct target for MKL1. MKL1 interacted with E2F1 to activate FOXM1 expression. Concordantly, FOXM1 depletion ameliorated MKL1-dependent VSMC proliferation. Of interest, ROS-induced MKL1 phosphorylation through MK2 was essential for its interaction with E2F1 and consequently FOXM1 trans-activation. Importantly, a positive correlation between FOXM1 expression and VSMC proliferation was identified in arterial specimens from patients with restenosis. Taken together, our data suggest that a redox-sensitive phosphorylation-switch of MKL1 activates FOXM1 transcription and mediates ROS fueled vascular smooth muscle proliferation. Targeting the MK-2/MKL1/FOXM1 axis may be considered as a reasonable approach for treatment of restenosis.

Injectable Hydrogel Capable of In Situ Covalent Crosslinking for Permanent Embolization

Vascular embolization provides an effective approach for the treatment of hemorrhage, aneurysms, and other vascular abnormalities. However, current embolic materials, such as metallic coils and liquid embolic agents, are limited by their inability to provide safe, consistent, and controlled embolization. Here, we report an injectable hydrogel that can remain at the injection site and subsequently undergo in situ covalent crosslinking, leading to the formation of a dual-crosslinking network (DCN) hydrogel for endovascular embolization. The DCN hydrogel is simple to prepare, easy to deploy via needles and catheters, and mechanically stable at the target injection site, thereby avoiding embolization of nontarget vessels. It possesses efficient hemostatic activity and good biocompatibility. The DCN hydrogel is also clearly visible under X-ray imaging, thereby allowing for targeted embolization. In vivo tests in a rabbit artery model demonstrates that the DCN hydrogel is effective in achieving immediate embolization of the target artery with long-term occlusion by inducing luminal fibrosis. Collectively, the DCN hydrogel provides a viable, biocompatible, and cost-effective alternative to existing embolic materials with clinical translation potential for endovascular embolization.