Acta biochimica et biophysica Sinica最新文献

Ultraviolet-B (UVB) radiation induces significant skin damage by penetrating into the dermal layer, leading to reactive oxygen species (ROS) generation and triggering cellular necrosis and apoptosis. Conventional sunscreens focus primarily on UVB blocking but are limited in their ability to repair dermal damage due to insufficient permeability. In this study, we discover that chebulinic acid (CA), one of the principal monomers in Terminalia chebula Retz., has superior efficacy in promoting recovery from UVB-induced skin damage compared with other major monomers. Mechanistically, CA's anti-UVB function involves regulating the expression of IL-6 and IFN-β through activation of the MAPK pathway. To overcome the formidable barrier posed by the skin, we identify mulberry exosome-like nanoparticles (MELNs) as an efficient transdermal delivery system and develop CA@MELNs loaded with CA. Furthermore, we demonstrate that the dissociative CA within the CA@MELNs delivery system significantly enhances both transdermal penetration and anti-UVB efficiency in vitro and in vivo. Our findings suggest the substantial potential of CA as an effective ingredient and CA@MELNs as a robust and accessible platform for mitigating UVB damage.

Cerebral ischemia-reperfusion injury (CIRI) significantly exacerbates neuronal damage following ischemic stroke. Emerging evidence implicates PANoptosis, a novel inflammatory form of programmed cell death, in CIRI pathogenesis. However, the role of Z-DNA-binding protein 1 (Zbp1), a key regulator of PANoptosis and innate immune responses, remains poorly understood in this context. Here, we establish a middle cerebral artery occlusion/reperfusion (MCAO/R) mouse model and an oxygen-glucose deprivation/re-oxygenation (OGD/R) model in which HT-22 cells are used to simulate CIRI and investigate the effects of Zpb1. Western blot analysis is performed to assess Zbp1 and PANoptosis-related protein expressions. Cell viability and death are evaluated using Hoechst 33342 staining and Calcein AM/PI assays, and the cerebral infarct volume is quantified using 2,3,5-triphenyltetrazolium chloride staining. Immunoprecipitation and mass spectrometry identify Ripk3 as a potential downstream effector of Zbp1. Furthermore, Zbp1 and PANoptosis-related proteins are significantly upregulated following OGD/R treatment. Zbp1 knockdown markedly reduces PANoptosis and cell injury in both models, decreases infarct volume and improves neurological outcomes in MCAO/R model mice. Conversely, Zbp1 overexpression exacerbates OGD/R-induced neuronal injury and PANoptosis in HT-22 cells. This effect is partially reversed by Ripk3 knockdown, indicating that Ripk3 mediates Zbp1-induced neuronal damage. These findings highlight Zbp1 as a promising therapeutic target in ischemic stroke and underscore the need for further research into Zbp1-mediated PANoptotic pathways to aid in the development of novel neuroprotective strategies.

Over the past decade, immunotherapy has emerged as a pivotal therapeutic strategy in cancer treatment. Immune checkpoint inhibitors (ICIs), such as CTLA-4 and PD-1 monoclonal antibodies, have demonstrated remarkable clinical efficacy in different types of cancer. However, the overall success rate of immune checkpoint therapies remains low. Investigating alternative immune checkpoint molecules is imperative. T-cell immunoglobulin and mucin-containing molecule-3 (TIM-3), which is expressed in T cells, natural killer (NK) cells, macrophages, and dendritic cells, has gained recognition as a promising candidate for tumor immunotherapy. Targeting TIM-3 represents a promising approach for cancer immunotherapy, particularly through the rational design of novel combination therapies with other ICIs. In this review, we present a comprehensive summary of the research advancements concerning the role of TIM-3 in regulating immune responses in different cell types and explore theoretical frameworks for targeting TIM-3 to achieve more effective immunotherapeutic breakthroughs.

Group 2 innate lymphoid cells (ILC2s), a subset of innate lymphoid cells (ILCs) lacking antigen-specific receptors and functionally mirroring T helper 2 (Th2) cells, are indispensable components of the innate immune system that lack antigen-specific receptors but phenotypically and functionally mirror T helper 2 (Th2) cells, particularly in their expression of the transcription factor GATA3 and the secretion of type 2 cytokines for mediating type 2 immune responses. ILC2s are tissue-resident cells in mucosal tissues, including the lung, where they play crucial roles in maintaining tissue homeostasis and regulating immune responses. ILC2s are poised to respond to environmental signals such as IL-25, IL-33, and TSLP, which activate and expand ILC2s. Their functions are highly context-dependent and influenced by interactions with other immune cells. In this review, we summarize recent findings on the roles of ILC2s in lung diseases, highlighting their typical characteristics and their responsiveness to environmental signals in the context of pulmonary pathology. We also discuss potential therapeutic strategies targeting ILC2s, which may offer new avenues for the treatment of inflammatory lung diseases. Understanding the mechanisms by which ILC2s contribute to lung disease progression will provide valuable insights for the development of novel diagnostic ( e. g., ILC2 phenotypic markers) and therapeutic approaches ( e. g., targeting ILC2 plasticity or alarmin-ILC2 signaling axes).

Macrophages are well known for their widespread distribution, diverse roles, and involvement in multiple pathophysiological contexts, thereby constructing an immunological front line. Meanwhile, constant efforts over the past few decades have unveiled diverse reprogramming patterns of lipid metabolism as crucial, response- and context-specific drivers of macrophage functions and fate. Here, we take a bird's-eye view of major fields across the research landscape of lipid-regulated macrophages; review the latest advances in understanding how alterations in several lipid subclasses, especially their fatty acyl composition and oxidative status, direct macrophage-mediated responses and pathology outcomes; and summarize representative insights that have deciphered the lipidome composition of macrophages or profiled specific lipid species under different scenarios. We hope that this review provides readers with a handy grip to learn and explore the field of lipid-regulated immunobiology, exemplified by but not limited to macrophages.

To determine whether lncRNA HNF1A-AS1 affects epithelial ovarian cancer (EOC) growth and macrophage polarization through miR-214/SEMA4D, the endogenous HNF1A-AS1 and miR-214 levels in human EOC cell lines are compared with those in normal ovarian epithelial IOSE80 cells. HNF1A-AS1 is overexpressed or silenced to investigate whether HNF1A-AS1 regulates miR-214/SEMA4D in SKOV3 cells and xenograft tumors, as well as the phenotypic switching of THP-1 cells. Compared with IOSE80 cells, EOC cells present significantly higher HNF1A-AS1 level and lower miR-214 level. Fluorescence in situ hybridization reveals predominant cytoplasmic localization of HNF1A-AS1, supporting its role as a competing endogenous RNA. HNF1A-AS1 and miR-214 antagonize each other in SKOV3 cells. In vitro, HNF1A-AS1 inhibits SKOV3 apoptosis and promotes migration and invasion. HNF1A-AS1 overexpression enhances miR-214 downstream of SEMA4D/PLEXIN-B1/TIAM1/RAC signaling, but miR-214 mimics significantly reverses this effect. Compared with control tumors, xenograft tumors derived from HNF1A-AS1-overexpressing SKOV3 cells present increased tumor growth, attenuated miR-214 expression, and activated SEMA4D/PLEXIN-B1/TIAM/RAC signaling. Knockdown of HNF1A-AS1 has the opposite effects. Additionally, HNF1A-AS1 promotes M2 phenotypic switching in THP-1 cells, which could be reversed by miR-214 overexpression or SEMA4D silencing. Our study suggests that by antagonizing miR-214, HNF1A-AS1 activates the SEMA4D/PLEXIN-B1/TIAM/RAC pathway, facilitating EOC growth and potentially promoting M2 macrophage polarization in the tumor microenvironment. HNF1A-AS1 represents a compelling therapeutic target for treating EOC.

The immune system orchestrates a delicate balance between robust defense against pathogens and restraint to prevent tissue damage, with T cells serving as central mediators of adaptive immunity. The canonical pathway for T-cell activation hinges on the precise recognition of peptide antigens presented by major histocompatibility complex (MHC) molecules via the T-cell receptor (TCR), which is complemented by essential co-stimulatory signals. However, this model alone cannot fully explain the nuanced contextualization of immune responses, particularly how T cells integrate signals related to the nature of the threat. Pattern recognition receptors (PRRs), which are traditionally studied in innate immune cells, are recognized as critical regulators of T cell function, challenging the conventional dichotomy between innate and adaptive immunity. T cell-intrinsic PRR signaling integrates endogenous danger signals and microbes to modulate critical processes, including cytokine production, proliferation, and polarization, thereby shaping immune responses and disease outcomes in contexts ranging from viral infections to chronic inflammation and cancer. However, the molecular mechanisms underlying PRR-mediated T cell regulation and their contributions to immune homeostasis or pathology remain incompletely understood. This study investigates the role of T cell-intrinsic PRR signaling in shaping immune responses and its implications for disease. By elucidating key signaling pathways and their impact on T cell function, we aim to offer novel insights into the complex regulation of T cell-mediated immunity and uncover an underappreciated paradigm for immune-related disorders, providing new insights into the pathogenesis of inflammatory and neoplastic diseases.

Bivalent chromatin maintains genes in low-expression, poised states in embryonic stem cells (ESCs). However, bivalent promoters correlate with the transcriptional activation of oncogenic programs in malignancies, a seemingly contradiction that remains to be resolved. Here, we identify a class of cancer-specific bivalent promoters (CSBPs) through the integration of a system-level longitudinal framework. Compared with ESCs, CSBPs are characterized by lower and narrower H3K27me3 deposition alongside abundant H3K4me3, thus permitting the persistent expression of genes critical for cancer stem cell (CSC) formation and maintenance, as exemplified by SOX9. The generation of CSBPs is essentially induced by the acquisition of H3K27me3 during cell state transition, which is mediated by specific binding of PRC2.1 and the de novo recruitment of PRC2.2. Notably, disrupting the bivalency of CSBPs significantly increases H3K4me3 levels, leading to hyperactivation of CSBPs and eventually inhibiting clonal expansion of CSCs and impairing tumorigenesis. Our study not only helps explain the puzzle of transcriptionally active bivalent genes in cancer but also provides insights into the development of therapies targeting phenotypic plasticity.