Latest ArticlesAlzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by cognitive decline and pathological brain changes. While aging is the primary risk factor, circadian rhythm disruption (CRD) is increasingly recognized as a central driver of AD pathology. CRD exacerbates oxidative stress, systemic inflammation, and gut microbiome dysbiosis, impairing sleep-wake cycles, disrupting metabolic homeostasis, and promoting neuroinflammation, ultimately accelerating disease progression. Oxidative stress, a key factor in neuronal damage, is both a cause and consequence of circadian misalignment, while mitochondrial dysfunction further amplifies oxidative damage, impairing synaptic function and cognitive stability. Additionally, gut microbiome dysbiosis contributes to neuroinflammatory processes, worsening neurodegeneration. Given these complex interactions, this review aims to elucidate the role of CRD in AD pathology and explore potential therapeutic interventions targeting circadian dysfunction. Specifically, it examines the efficacy of time-restricted feeding (TRF), a dietary strategy that aligns food intake with circadian rhythms. TRF has shown promise in restoring circadian function, reducing oxidative stress, improving mitochondrial health, and promoting gut microbiome diversity. By addressing CRD, TRF may offer a novel approach to mitigating AD pathologies. This review also identifies current research gaps and future directions for developing circadian-based interventions in AD prevention and treatment.
Chronic kidney disease (CKD) affects 8%–15% of the population globally and can cause renal failure, partly due to lack of effective treatments and drug targets. Three novel cembrane diterpenoids papyifurans A‒C (1–3), in particular of 1 with an unprecedented trioxatetracyclo[10.2.1.12,5.16,9]heptadecane polyether scaffold, derived from Boswellia papyrifera resin, were found to effectively protect against renal fibrosis in vitro and in vivo. Their structures were fully characterized using a combination of spectroscopic, computational, modified Mosher’s, and X-ray crystallographic analysis. In particular, we performed chemical proteomic analyses and found that Elongation factor 2 (EEF2) is the key target of compound 1 for anti-renal fibrosis in vitro. Moreover, previous studies have linked EEF2 with lung fibrosis, while compound 1 was found to inhibit the hallmarks of organ fibrosis in vitro. Such effects were observed to decrease with the knock down of EEF2 in vitro, suggesting that EEF2 might be a universal drug target of organ fibrosis. Collectively, the present study demonstrated an example of identifying drug targets by using structurally novel natural products, which will be beneficial for developing therapeutic agents against organ fibrosis.
Idiopathic 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.