Xi-Long Zheng

Platycodin D (PD), a triterpenoid saponin from Platycodon grandiflorus, has been reported to have cardiovascular activity, but its actions in vascular smooth muscle cells (VSMCs) and atherosclerosis remain unclear. We integrated network pharmacology, molecular docking, 100-ns molecular dynamics simulation, VSMC assays, and two mouse carotid models. In VSMCs cultured under basal conditions, PD reduced viability and BrdU incorporation, downregulated cyclin D1/E1, and induced TUNEL positivity and cleaved caspase-3. At the cellular level, PD activated mTORC1-associated signaling, increased p70S6K and eIF2α phosphorylation, increased ATF4 protein and activated ATF6, impaired autophagic flux, and induced CHOP-associated endoplasmic reticulum stress. Rapamycin and 4-phenylbutyric acid attenuated PD-induced apoptosis, whereas MHY1485 and thapsigargin exacerbated it. Perivascular PD reduced neointimal hyperplasia after complete carotid ligation in C57BL/6J mice. In contrast, PD accelerated early carotid atherosclerosis after partial ligation in ApoE^-/- mice fed a high-fat diet. Under ox-LDL challenge, PD increased VSMC lipid accumulation, Olr1/Cd36 expression, mTORC1-p70S6K signaling, and BrdU incorporation; rapamycin limited these effects. These findings suggest that PD activates an mTORC1-associated stress program whose vascular outcome depends on lipid and flow context. PD may have local anti-neointimal potential but warrants caution in hyperlipidemic atherosclerosis.

Uterine leiomyosarcoma (ULMS) is a rare yet aggressive uterine malignancy with high recurrence and poor survival, prompting an urgent search for better treatments. We investigated whether atorvastatin, an HMG-CoA reductase inhibitor, could suppress ULMS growth by targeting mevalonate pathway-dependent prenylation. Human ULMS cell lines received atorvastatin ± isoprenoids to assess proliferation, cell-cycle distribution, and smooth muscle contractility, whereas proteomic profiling (LC-MS/MS) and in vivo xenografts were used to evaluate molecular pathways and antitumor efficacy. Atorvastatin inhibited ULMS proliferation in a dose-dependent manner, induced G₀/G₁ cell-cycle arrest, and diminished the contractile phenotype. Geranylgeranyl pyrophosphate rescued these effects, implicating geranylgeranylation as the key dependency, and Rap1A/Rap1B Western blotting confirmed functional GGPP depletion. In xenografts, atorvastatin suppressed ULMS tumor growth by ~50% with minimal toxicity, as evidenced by normal serum ALT and creatinine levels and preserved organ histology. These findings identify protein geranylgeranylation as a novel therapeutic vulnerability in ULMS and support statin repurposing as a promising treatment strategy.

Neointimal hyperplasia, driven by abnormal proliferation and survival of vascular smooth muscle cells (VSMCs), underlies atherosclerotic stenosis and restenosis after angioplasty or stenting. Edelfosine (ET-18-OCH₃) is an alkylphospholipid with pro-apoptotic activity. We tested whether edelfosine limits pathological VSMC growth and neointimal lesion formation by enforcing cell-cycle arrest and apoptosis. Primary VSMCs from mouse and rat aortas were exposed to edelfosine (0–15 µM). Viability (MTT) and DNA synthesis (BrdU) were quantified. DNA content and binucleation were assessed by laser scanning cytometry and immunofluorescence. Apoptosis was measured by TUNEL and by cleavage of caspase-9, -7, and -3, with the pan-caspase inhibitor Z-VAD-FMK to test caspase dependence. Apoptosis in live cells was also analyzed using Annexin V and propidium iodide staining. Intracellular Ca²⁺ was imaged and measured in fluorescent Ca²⁺ indicator-loaded cells. In vivo, carotid artery ligation in mice induced neointimal hyperplasia; edelfosine or vehicle was delivered locally, and lesion size was measured morphometrically. Vascular apoptosis was further evaluated by TUNEL. Edelfosine reduced VSMC viability and proliferation in a dose- and time-dependent manner; at 5–10 µM it suppressed BrdU incorporation by > 90% and triggered extensive cell death. Cells accumulated with 4 N DNA content and showed increased binucleation, consistent with G₂/M arrest and failed cytokinesis. Approximately 40% of edelfosine-treated VSMCs were TUNEL-positive versus ~ 5% with vehicle (p < 0.001), coincident with activation of caspase-9, -7, and -3; Z-VAD-FMK prevented caspase-3 cleavage and reduced TUNEL positivity. Mechanistically, edelfosine induced endoplasmic reticulum (ER) stress (increased phospho-eIF2α), upregulated Bax, and evoked a rapid rise in intracellular Ca²⁺ in the presence of extracellular Ca²⁺. Edelfosine-induced Ca²⁺ elevation was reduced by extracellular Ca²⁺ chelation with EGTA, blockade of VGCCs with nifedipine, and perturbation of IP₃ receptor-linked Ca²⁺ pathways with 2-APB. In vivo, edelfosine significantly reduced neointimal lesion size after carotid ligation, lowering the intima-to-lumen ratio (p < 0.05) and increasing TUNEL positivity within the vessel wall. Edelfosine enforces G₂/M cell-cycle arrest and caspase-dependent apoptosis in VSMCs, linked to ER stress and Ca²⁺ influx, thereby limiting neointimal hyperplasia after blood flow cessation. Local edelfosine delivery may offer a dual anti-proliferative and pro-apoptotic strategy to prevent restenosis.

Aging is associated with both a chronic pro-inflammatory state (“inflammaging”) and the accumulation of somatic mutations in hematopoietic stem cells leading to clonal hematopoiesis. Clonal hematopoiesis of indeterminate potential (CHIP) is now recognized as a common phenomenon in older adults, defined by the expansion of blood cell clones bearing leukemia-associated mutations in the absence of overt malignancy. Mounting evidence links CHIP to an increased risk of cardiovascular disease (CVD) in older adults, particularly atherosclerotic disease, through inflammatory mechanisms that intersect with inflammaging. In this review, we outline the biology of clonal hematopoiesis in aging and its relationship with age-related inflammation, discuss mechanistic insights into how mutated hematopoietic clones accelerate vascular pathology, and explore emerging approaches for risk stratification and therapy. Key mutations (e.g., in DNMT3A, TET2, ASXL1, JAK2) drive clonal expansions that not only predispose to hematologic malignancies but also contribute to a pro-inflammatory milieu that promotes atherosclerosis, heart failure, and other vascular complications. We examine how the concept of inflammaging provides a framework for understanding the bidirectional interplay between aging immune clones and cardiovascular risk. Finally, we review therapeutic frontiers, from aggressive management of conventional risk factors to novel anti-inflammatory strategies and potential clone-targeted interventions. Greater understanding of clonal hematopoiesis in older patients could transform risk assessment and usher in personalized strategies to mitigate cardiovascular disease in our aging population. For the purposes of this review, we use “older adults” to refer to individuals aged ≥ 65 years (unless otherwise specified).

Glutaminase-1 (GLS1) converts glutamine to glutamate, fueling anaplerosis, redox defense, and biosynthesis. We synthesize animal, cellular, and human (bulk/single-cell) data to define cell- and stage-specific roles of GLS1 in atherosclerosis and to outline translational opportunities. In early disease, GLS1 drives vascular smooth muscle proliferation, endothelial sprouting, and inflammatory macrophage activation, promoting plaque growth and neovascularization. In advanced plaques, GLS1 sustains fibrous-cap VSMC survival, endothelial barrier function, and macrophage efferocytosis, limiting necrosis and enhancing stability; excessive glutamate may favor calcification. We also connect GLS1 to vascular senescence and ferroptosis. We propose precision use of GLS1 modulation: a proof-of-concept strategy is short-term telaglenastat (CB-839) after angioplasty to curb neointimal hyperplasia, guided by glutamine-PET and biomarkers to avoid destabilizing mature plaques. GLS1 emerges as a tunable metabolic checkpoint whose effects depend on cell state and disease stage; judicious, time-limited modulation could complement lipid-lowering and anti-inflammatory therapies in cardiovascular disease. Graphical Abstract

Monomethyl fumarate (MMF), the active metabolite of dimethyl fumarate, an immunomodulatory drug approved for multiple sclerosis and psoriasis, has emerging potential in ischemic heart disease. We investigated whether MMF can attenuate myocardial infarction (MI) injury and delineated the underlying mechanisms, focusing on hydroxycarboxylic acid receptor 2 (HCAR2, also known as GPR109A) and PI3K/Akt signaling. In a mouse MI model induced by permanent left anterior descending coronary artery ligation, MMF administration prior to ischemia significantly preserved left ventricular function and reduced cardiomyocyte apoptosis compared with untreated MI. Echocardiography and pressure–volume loop analyses demonstrated higher ejection fraction and cardiac output in MMF-treated MI mice, accompanied by attenuation of adverse ventricular remodeling. TUNEL staining and analysis of apoptotic markers showed that MMF decreased myocardial cell death and caspase-3 activation in vivo, while concomitantly upregulating HCAR2 expression and enhancing Akt phosphorylation in ischemic myocardium. In vitro, MMF protected HL-1 cardiomyocytes from CoCl₂-induced hypoxic injury, improving cell viability and reducing apoptosis, as evidenced by fewer TUNEL-positive cells and a lower Bax/Bcl-2 ratio compared with hypoxia alone. Pharmacological inhibition of Gi-coupled signaling with pertussis toxin or siRNA-mediated knockdown of HCAR2 abolished MMF’s cytoprotective effects and blunted MMF-induced Akt phosphorylation, and PI3K/Akt pathway inhibition eliminated MMF’s anti-apoptotic benefits in vitro. Collectively, these findings demonstrate that MMF markedly reduces ischemic cardiomyocyte injury via an HCAR2-dependent mechanism involving activation of the pro-survival PI3K/Akt pathway, establishing a novel cardioprotective role for MMF and supporting its translational potential as a therapeutic strategy to mitigate acute MI injury.

Fumarate is increasingly recognized as a metabolic signal with dual effects in cardiovascular disease. Pharmacologic doses of dimethyl fumarate (DMF) and its metabolite monomethyl fumarate (MMF) transiently activate Nrf2 and HCAR2 pathways, offering antioxidant, anti-inflammatory, and antifibrotic benefits. These include reduced endothelial activation, macrophage foam cell formation, and vascular remodeling in atherosclerosis, ischemia–reperfusion injury, hypertension, and diabetic cardiomyopathy. In contrast, sustained fumarate accumulation—due to fumarate hydratase 1 (FH1) loss—drives protein succination, cGAS–STING activation, HIF-1α stabilization, and epigenetic enzyme inhibition, promoting oxidative stress, inflammation, and cellular senescence. FH1 insufficiency is associated with plaque destabilization, renal dysfunction, and galectin-3–driven fibrosis. Despite promising preclinical results, human data remain limited: FH1 mutation syndromes rarely present with cardiovascular phenotypes, and DMF clinical trials have not evaluated major cardiovascular endpoints. Future studies should define a therapeutic window, develop succination biomarkers, and assess long-term effects to safely harness fumarate’s hormetic potential in cardiovascular medicine. Graphical Abstract

BACKGROUND: Growing evidence suggests that the epigenetic reader Brd4 (bromodomain-containing protein 4) is involved in aging and aging-related diseases. However, the specific mechanisms by which Brd4 influences vascular aging, especially senescence of vascular smooth muscle cells (SMCs), remain unexplored. METHODS: Primary cell cultures were established using mouse aortic SMCs and treated with Brd4 inhibitor, ARV-825, or (+)-JQ1. Primary Brd4 ^flox/flox mouse aortic SMCs were transduced with Ad-Cre virus to induce Brd4 knockout (KO). Senescence was assessed through SA-β-gal (senescence-associated β-galactosidase) staining. A mouse model of inducible SMC-specific Brd4 gene KO (SMC-Brd4-KO) was generated with the Cre-LoxP system. The control and SMC-Brd4-KO mice were evaluated for arterial contractility, blood pressure, arterial stiffness, and Ang II (angiotensin II)–induced vascular aging, as well as transcriptome profiling using RNA-sequencing analysis. RESULTS: Brd4 inhibition with ARV-825, (+)-JQ1, or Brd4 knockdown through Ad-Cre virus in Brd4 ^flox/flox SMCs led to cellular senescence. Induced SMC-Brd4-KO in adult mice prevented neointima formation. SMC-Brd4-KO mice exhibited increased aortic stiffness and blood pressure with enhanced arterial contractility ex vivo. In addition, Brd4 expression was downregulated in aortic tissues of aged mice and senescent human aortic SMCs. Furthermore, SMC-Brd4-KO mice displayed more prominent histopathologic features of vascular aging in response to Ang II infusion. Aortic tissues from SMC-Brd4-KO mice showed a more robust contractile response to Ang II and phenylephrine, accompanied by multiple genetic changes, including alterations in cytoskeleton genes. Transcriptomes of Brd4 KO aortas displayed gene signatures of dampened autophagy, intriguingly associated with a downregulation of microtubule genes, including Tuba4a (α-tubulin). Experiments in vitro with Brd4 KO SMCs demonstrated the potential role of impaired autophagy and depleted α-tubulin in mediating induction of senescence in SMCs. CONCLUSIONS: Brd4 depletion in SMCs induces senescence, prevents neointima formation, and exacerbates vascular aging, highlighting its crucial roles in vascular functions and diseases.