Latest ArticlesIdiopathic pulmonary fibrosis (IPF), a chronic interstitial lung disease, is characterized by aberrant wound healing, excessive scarring and the formation of myofibroblastic foci. Although the role of alternative splicing (AS) in the pathogenesis of organ fibrosis has garnered increasing attention, its specific contribution to pulmonary fibrosis remains incompletely understood. In this study, we identified an up-regulation of serine/arginine-rich splicing factor 7 (SRSF7) in lung fibroblasts derived from IPF patients and a bleomycin (BLM)-induced mouse model, and further characterized its functional role in both human fetal lung fibroblasts and mice. We demonstrated that enhanced expression of Srsf7 in mice spontaneously induced alveolar collagen accumulation. Mechanistically, we investigated alternative splicing events and revealed that SRSF7 modulates the alternative splicing of pyruvate kinase (PKM), leading to metabolic dysregulation and fibroblast activation. In vivo studies showed that fibroblast-specific knockout of Srsf7 in conditional knockout mice conferred resistance to bleomycin-induced pulmonary fibrosis. Importantly, through drug screening, we identified lomitapide as a novel modulator of SRSF7, which effectively mitigated experimental pulmonary fibrosis. Collectively, our findings elucidate a molecular pathway by which SRSF7 drives fibroblast metabolic dysregulation and propose a potential therapeutic strategy for pulmonary fibrosis.
Myocardial fibrosis (MF) is a common pathological hallmark of cardiovascular diseases, reflecting shared mechanisms in their progression. However, the lack of reliable MF models that accurately mimic its pathogenesis has hindered drug discovery, highlighting the urgent need for more effective therapeutic agents. Herein, a novel contractile three-dimensional (3D) myocardial tissue model integrating cardiomyocytes, cardiac-fibroblasts, and bone marrow-derived macrophages in collagen hydrogel was developed to simulate the fibrotic changes of cardiovascular disease, and facilitate the screening of anti-MF compounds. The 3D myocardial tissue model exhibited precise, visualizable, and quantifiable contractile characteristics under hypoxia and drug interventions. 76 compounds extracted from the resins of Toxicodendron vernicifluum, a traditional Chinese medicine with clear clinical benefits for fibrotic diseases, were screened for anti-fibrotic activity. Using an in vitro 3D oxygen–glucose deprivation (OGD)-treated myocardial tissue model instead of a two-dimensional transforming growth factor-β treated cardiac-fibroblasts model, two candidates including LQ-40 and SQ-3 exert impressive anti-MF activity, which was further validated in left anterior descending coronary artery ligation-induced MF mouse model. The current results demonstrate the feasibility and advantage of the novel contractile 3D tissue model with multi-cell types in discovering candidates for MF, further stressing the great potential of regulating macrophages in the treatment of MF.
Acute kidney injury (AKI) has high morbidity and mortality, but effective clinical drugs and management are lacking. Previous studies have suggested that macrophages play a crucial role in the inflammatory response to AKI and may serve as potential therapeutic targets. Emerging evidence has highlighted the importance of forkhead box protein O1 (FoxO1) in mediating macrophage activation and polarization in various diseases, but the specific mechanisms by which FoxO1 regulates macrophages during AKI remain unclear. The present study aimed to investigate the role of FoxO1 in macrophages in the pathogenesis of AKI. We observed a significant upregulation of FoxO1 in kidney macrophages following ischemia–reperfusion (I/R) injury. Additionally, our findings demonstrated that the administration of FoxO1 inhibitor AS1842856-encapsulated liposome (AS-Lipo), mainly acting on macrophages, effectively mitigated renal injury induced by I/R injury in mice. By generating myeloid-specific FoxO1-knockout mice, we further observed that the deficiency of FoxO1 in myeloid cells protected against I/R injury-induced AKI. Furthermore, our study provided evidence of FoxO1’s pivotal role in macrophage chemotaxis, inflammation, and migration. Moreover, the impact of FoxO1 on the regulation of macrophage migration was mediated through RhoA guanine nucleotide exchange factor 1 (ARHGEF1), indicating that ARHGEF1 may serve as a potential intermediary between FoxO1 and the activity of the RhoA pathway. Consequently, our findings propose that FoxO1 plays a crucial role as a mediator and biomarker in the context of AKI. Targeting macrophage FoxO1 pharmacologically could potentially offer a promising therapeutic approach for AKI.
Tailored lipid nanoparticles (LNPs)-mediated small interfering RNA (siRNA) nanomedicines show promise in treating liver disease, such as acute liver injury (ALI) and non-alcoholic steatohepatitis (NASH). However, constructing LNPs that address biosafety concerns, ensure efficient delivery, and target specific hepatic subcellular fractions has been challenging. To evade above obstacles, we develop three novel self-degradable “gemini-like” ionizable lipids (SS-MA, SS-DC, SS-MH) by incorporating disulfide bonds and modifying the length of ester bond and tertiary amino head. Our findings reveal that the disulfide-bond-bridged LNPs exhibit reduction-responsive drug release, improving both biosafety and siRNA delivery efficiency. Furthermore, the distance of ester bond and tertiary amino head significantly influences the LNPs’ pKa, thereby affecting endosomal escape, hemolytic efficiency, absorption capacity of ApoE, uptake efficiency of hepatocytes and liver accumulation. We also develop the modified-mannose LNPs (M-LNP) to target liver macrophages specifically. The optimized M-MH_LNP@TNFα exhibits potential in preventing ALI by decreasing tumor necrosis factor α (TNFα) levels in the macrophages, while MH_LNP@DGAT2 could treat NASH by selectively degrading diacylglycerol O-acyltransferase 2 (DGAT2) in the hepatocytes. Our findings provide new insights into developing novel highly effective and low-toxic “gemini-like” ionizable lipids for constructing LNPs, potentially achieving more effective treatment for hepatic diseases.
Triple-negative breast cancer (TNBC) is aggressive, with high recurrence rates and poor prognosis. Paclitaxel (PTX) remains a key chemotherapeutic agent for TNBC, but its efficacy diminishes due to the emergence of drug resistance, largely driven by cancer stem-like cells (CSCs), vasculogenic mimicry (VM) formation and tumor immunosuppressive microenvironment (TIME). Pyruvate kinase M2 (PKM2) is highly expressed in TNBC, and is a potential target for TNBC treatment. In this study, we developed a biomimetic codelivery system using albumin nanoparticles (termed S/P NP) to co-encapsulate PTX and shikonin (SHK), a natural inhibitor of PKM2. By inhibiting PKM2, SHK suppressed β-Catenin signaling, thereby reversing CSC stemness and preventing VM formation. The S/P NP system exhibited tumor-targeting delivery effect and significantly inhibited TNBC growth and lung metastasis. Mechanistically, the treatment reversed epithelial–mesenchymal transition (EMT) and stem-like properties of TNBC cells, suppressed VM formation, and remodeled the TIME. It reduced immunosuppressive cells (M2 macrophages, MDSCs) while promoting anti-tumor immunity (M1 macrophages, dendritic cells, cytotoxic T cells, and memory T cells). This dual-action strategy holds promise for improving TNBC therapy by targeting CSCs, VM, and the immune microenvironment, and for overcoming PTX resistance and reducing metastasis.
Mitochondrial dysfunction is a critical factor in the pathogenesis of Alzheimer's disease (AD). The mitochondrial contact site and cristae organizing system (MICOS) plays a pivotal role in shaping the inner mitochondrial membrane, forming cristae junctions and establishing interaction sites between the inner and outer mitochondrial membranes and thereby serving as a cornerstone of mitochondrial structure and function. In the past decade, MICOS abnormalities have been extensively linked to AD pathogenesis. In particular, dysregulated expression of MICOS subunits and mutations in MICOS-related genes have been identified in AD, often in association with hallmark pathological features such as amyloid-β plaque accumulation, neurofibrillary tangle formation, and neuronal apoptosis. Furthermore, MICOS subunits interact with several etiologically relevant proteins, significantly influencing AD progression. The intricate crosstalk between these proteins and MICOS subunits underscores the relevance of MICOS dysfunction in AD. Therapeutic strategies targeting MICOS subunits or their interacting proteins may offer novel approaches for AD treatment. In the present review, we introduce current understanding of MICOS structures and functions, highlight MICOS pathogenesis in AD, and summarize the available MICOS-targeting drugs potentially useful for AD.
Metastasis serves as an indicator of malignancy and is a biological characteristic of carcinomas. Epithelial–mesenchymal transition (EMT) plays a key role in the promotion of tumor invasion and metastasis and in the enhancement of tumor cell aggressiveness. Prostaglandin E synthase 3 (p23) is a cochaperone for heat shock protein 90 (HSP90). Our previous study showed that p23 is an HSP90-independent transcription factor in cancer-associated inflammation. The effect and mechanism of action of p23 on lung cancer metastasis are tested in this study. By utilizing cell models in vitro and mouse tail vein metastasis models in vivo, the results provide solid evidence that p23 is critical for promoting lung cancer metastases by regulating downstream CXCL1 expression. Rather than acting independently, p23 forms a complex with RNA-binding motif protein 14 (RBM14) to facilitate EMT progression in lung cancer. Therefore, our study provides evidence for the potential role of the RBM14–p23–CXCL1–EMT axis in the metastasis of lung cancer.
Alzheimer's disease (AD), characterized by β-amyloid (Aβ) aggregation and neuroinflammation, remains a formidable clinical challenge. Herein, we present an innovative nose-to-brain delivery platform utilizing lactoferrin (Lf)-functionalized lipid nanoparticles (LNPs) co-encapsulating α-mangostin (α-M) and β-site APP cleaving enzyme 1 (BACE1) siRNA (siB). This dual-modal therapeutic system synergistically combines the neuroprotective and microglia-reprogramming capabilities of α-M with the transcriptional silencing of BACE1 via siB, thereby simultaneously inhibiting Aβ production and enhancing its clearance. Fabricated via a microfluidic approach, the LNPs exhibited uniform particle size distribution, great encapsulation efficiency, and robust colloidal stability. Upon intranasal administration, Lf-functionalization enabled superior brain-targeting efficacy through receptor-mediated transcytosis. In vitro studies demonstrated that α-M reversed Aβ-induced low-density lipoprotein receptor downregulation, promoting microglial phagocytosis and autophagic degradation of Aβ, while siB effectively suppressed BACE1 expression, abrogating Aβ synthesis. In vivo investigations in APP/PS1 transgenic mice revealed remarkable cognitive recovery, substantial Aβ plaque reduction, and alleviation of neuroinflammation and oxidative stress. This intricately designed LNP system, exploiting a non-invasive and efficient nose-to-brain delivery route, provides a biocompatible, synergistic, and transformative therapeutic strategy for the multifaceted management of AD.