The FASEB Journal最新文献

Microglial activation and pyroptosis are central to neuroinflammation and significantly contribute to cognitive decline associated with neurodegenerative diseases. Alpha protein kinase 1 (ALPK1) is recently identified as a critical mediator of inflammatory responses in response to ADP-heptose (a pathogen-associated molecular pattern). However, its specific role in microglial pyroptosis and cognitive dysfunction remains unclear. In this study, we investigated the effects of ALPK1 on cognitive function and pyroptosis in wild-type (WT) and ALPK1 KO mice by intracerebroventricular administration of ADP-heptose to induce neuroinflammation. Cognitive performance was evaluated using behavioral tests (the Y-Maze, Morris Water Maze, and step-down passive avoidance), while Western blot, immunofluorescence, transmission electron microscopy, and enzyme-linked immunosorbent assay were used to evaluate the expression of pyroptosis markers such as NLRP3, Caspase-1, and gasdermin D (GSDMD) in vivo and in vitro. Our results reveal that the absence of ALPK1 significantly attenuated ADP-heptose-induced cognitive deficits and neuronal injury, and inhibited the NLRP3/Caspase-1/GSDMD pathway of pyroptosis and the secretion of pro-inflammatory cytokines IL-1β and IL-18. Notably, ADP-heptose-stimulated conditioned media from primary microglial cells of ALPK1 KO mice significantly enhanced neuronal cell viability, suggesting a protective role for ALPK1 deficiency in supporting neuronal health. These findings suggest the pivotal role of ALPK1 in ADP-heptose-induced microglial pyroptosis and cognitive impairment, thereby highlighting its potential as a therapeutic target in neuroinflammatory disorders.

Renal ischemia–reperfusion injury (IRI) is a prevalent cause of acute kidney injury, however, the regulatory mechanisms of miR-374b-5p in renal IRI remain poorly understood. We established hypoxia/reoxidation (H/R)-induced renal injury models using HK-2 and TCMK-1 cells, as well as an ischemia–reperfusion (I/R)-induced mouse model. Renal tubular epithelial cells (RTECs) viability and apoptosis were assessed using CCK-8, flow cytometry, and TUNEL assays. The targeting relationship between miR-374b-5p and SRSF7 was analyzed using dual luciferase reporter assays. The interaction between METTL3 and miR-374b-5p was confirmed through methylated RNA immunoprecipitation (MeRIP) and co-immunoprecipitation (Co-IP) assays. We found that miR-374b-5p levels were significantly upregulated in H/R-induced HK-2 and TCMK-1 cells. Furthermore, miR-374b-5p promoted H/R-induced RTEC injury by suppressing cell viability and exacerbating apoptosis. SRSF7 was identified as a downstream target of miR-374b-5p, inhibition of SRSF7 reversed the inhibitory effects of miR-374b-5p inhibitors on RTEC injury. Additionally, METTL3 interacted with the microprocessor protein DGCR8 and modulated the processing of pri-miR-374b-5p in an m6A-dependent manner. In the renal IRI model, METTL3 and miR-374b-5p levels were upregulated, and knockdown of METTL3 inhibited apoptosis in H/R-induced HK-2 and TCMK-1 cells. Conversely, miR-374b-5p reversed the protective effects of METTL3 knockdown on renal IRI. Our findings provide novel insights into the role of m6A methylation in the development of renal IRI, demonstrating that METTL3 promotes renal IRI by modulating the miR-374b-5p/SRSF7 axis.

Discrimination is a social adversity that is linked to several age-related outcomes. However, the molecular drivers of these observations are poorly understood. Social adverse factors are associated with proinflammatory and interferon gene expression, but little is known about whether additional genes are associated with discrimination among both African American and White adults. In this study, we examined how perceived discrimination in African American and White adults was associated with genome-wide transcriptome differences using RNA sequencing. Perceived discrimination was measured based on responses to self-reported lifetime discrimination and racial discrimination. Differential gene expression and pathway analysis were conducted in a cohort (N = 59) stratified by race, sex, and overall discrimination level. We found 28 significantly differentially expressed genes associated with race among those reporting high discrimination. Several of the upregulated genes for African American versus White adults reporting discrimination were related to immune function IGLV2-11, S100B, IGKV3-20, and IGKV4-1; the most significantly downregulated genes were associated with immune modulation and cancer, LUCAT1, THBS1, and ARPIN. The most enriched gene ontology biological process between African American and White men reporting high discrimination was the regulation of cytokine biosynthetic processes. The immune response biological process was significantly lower for African American women compared to White women reporting high discrimination. Discrimination was associated with the expression of small nucleolar RNAs, long noncoding RNAs, and microRNAs associated with energy homeostasis, cancer, and actin. Understanding the pathways through which adverse social factors like discrimination are associated with gene expression is crucial in advancing knowledge of age-related health disparities.

Junjie, Zhu,Peng, Chen,Jiaojiao, Liang et al. Inhibition of CK2α accelerates skin wound healing by promoting endothelial cell proliferation through the Hedgehog signaling pathway. FASEB J. 2023;37:e23135.

Affiliation Section: the affiliation of one of the authors, Junjie Zhu is incorrect.

The correct affiliation for Junjie Zhu is as follows: “Department of Cardiology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, P.R. China.”

Correct author list: Junjie Zhu^1,2, Peng Chen¹, Jiaojiao Liang⁴, Zhaohang Wu², Haiqun Jin⁵, Tianpeng Xu², Yeyi Zheng², Hongfang Ma², Weitao Cong^2,3, Xu Wang², Xueqiang Guan¹

We apologize for this error.

Hemolytic anemia (HA) is characterized by massive destruction of red blood cells (RBCs) and insufficient oxygen supply, which can lead to shock, organ failure, even death. Recent studies have preliminarily demonstrated the therapeutic effectiveness of whole blood exchange (WBE) in the management of acute hemolytic anemia and exhibited potential for reducing the duration of corticosteroid treatment, while the underlying mechanism of WBE therapy was not investigated in preclinical study. Hence, we investigate the therapeutic mechanisms of WBE in HA through established continued WBE therapy in rats creatively. This study aims to examine the mechanism of WBE on phenylhydrazine hydrochloride-induced hemolytic anemia in SD rats to aid the development of therapeutics for drug-induced hemolytic anemia (DIHA). Research results demonstrated the efficacy of WBE therapy in reducing mortality and ameliorating anemia in DIHA, as evidenced by significant improvements in representative hematological parameters such as RBCs, hemoglobin, and lactate dehydrogenase levels. Additionally, WBE indicated the ability to suppress oxidative stress and inflammation, and it mitigated organ damage and biochemical function by stabilizing hepatic ferroportin levels and decreasing organ iron content. These results highlighted the effectiveness of WBE as an innovative treatment for HA, furnishing evidence to prioritize it over traditional blood transfusion for severe anemias.

Xuefu Zhuyu Decoction (XZD) is widely used in the treatment of cardiovascular diseases. The purpose of this study was to explore the pharmacological effects and molecular mechanisms of XZD in improving hyperlipidemia and to provide a theoretical framework for clinical application. In this study, the signaling pathways regulated by XZD in improving hyperlipidemia were predicted by network pharmacology. Molecular docking was used to verify the affinity between the components in XZD and the target. Furthermore, a hyperlipidemic model in rats was constructed through feeding a high-fat diet. The effect of XZD on hyperlipidemia was verified by histopathological staining, Elisa, and western blot. The results found that the XZD improved dyslipidemia and inflammatory factor disorders, and inhibited liver function damage, pathological damage, and oxidative stress damage in hyperlipidemic rats. The findings from molecular docking and network pharmacology suggested that the mechanism of XZD improving hyperlipidemia may be closely related to the MAPK, NF-κB, and PPAR pathways. This study demonstrated that the XZD inhibited liver lipid metabolism disorder and inflammatory response by regulating the MAPK/NF-κB and MAPK/PPARα/CPT-1A pathway, significantly improved liver histopathological damage and oxidative stress injury, and played a protective role in hyperlipidemic rats.

Renal fibrosis is a common pathological process in various chronic kidney diseases. The accumulation of senescent renal tubular epithelial cells (TECs) in renal tissues plays an important role in the development of renal fibrosis. Eliminating senescent TECs has been proven to effectively reduce renal fibrosis. Procyanidin C1 (PCC1) plays a senolytic role by specifically eliminating senescent cells and extending its overall lifespan. However, whether PCC1 can alleviate unilateral ureteral obstruction (UUO)-induced renal fibrosis and the associated therapeutic mechanisms remains unclear. Here, we observed a marked increase in senescent TECs within obstructed human renal tissue and demonstrated the positive correlation between the accumulation of senescent TECs and renal fibrosis in UUO-induced renal fibrosis in mice. We found that PCC1 reduced the number of senescent TECs, restored the regenerative phenotype in kidneys with reduced fibrosis, and improved tubular repair after UUO-induced injury. In vitro, PCC1 effectively cleared senescent HK2 cells by inducing apoptosis via ANGPTL4/NOX4 signaling. Incubation with culture medium from senescent HK2 cells promoted fibroblast activation, whereas PCC1 impeded profibrotic effects by downregulating senescence-associated secretory phenotype (SASP) factors from senescent HK2 cells. Therefore, PCC1 alleviated interstitial renal fibrosis not only by clearing senescent TECs and improving tubular repair but also by indirectly attenuating myofibroblast activation by reducing the level of SASP. In summary, PCC1 may be a novel therapeutic senolytic agent for treating renal fibrosis.

Nonunion is a significant complication in fracture management for surgeons. Salvianolic acid A (SAA), derived from the traditional Chinese plant Salviae miltiorrhizae Bunge (Danshen), exhibits notable anti-inflammatory and antioxidant properties. Although studies have demonstrated its ability to promote osteogenic differentiation, the exact mechanism of action remains unclear. This study investigated the effects of various SAA concentrations on the osteogenic differentiation of mouse-derived bone marrow mesenchymal stem cells (mBMSCs) and the osteoclastic differentiation of bone marrow-derived macrophages. Our findings indicate that SAA promotes the osteogenic differentiation of mBMSCs in a concentration-dependent manner, primarily by inhibiting the Notch1 signaling pathway. Notably, the administration of two Notch1 agonists (Jagged-1 and VPA) inhibited the effects of SAA on osteogenic differentiation. Additionally, SAA facilitated the autophagic degradation of NICD1, further enhancing osteogenic differentiation. Furthermore, SAA also dose-dependently inhibited the osteoclastic differentiation of bone marrow-derived macrophages, which is linked to its suppression of NF-κB signaling pathways. In a fracture model, SAA demonstrated a capacity to promote healing. In conclusion, SAA enhances bone fracture healing by balancing osteoblast and osteoclast differentiation.

Nuclear factor of activated T-cells 5 (NFAT5) is a transcription factor known for its role in osmotic stress adaptation in the renal inner medulla, due to the osmotic gradient that is generated between the renal cortex and renal inner medulla. However, its broader implications in kidney injury and chronic kidney disease (CKD) are less understood. Here we used two different Cre deleter mice (Ksp1.3-Cre and Aqp2-Cre) to generate tubule segment and even cell type-specific NFAT5-deficient mice and performed extensive gene expression profiling. In both Nfat5 knockout models, we observed massive changes in gene expression pattern, with heightened inflammatory responses and renal injury, culminating in renal fibrosis. Interestingly, inflammatory responses were much more prominent in the Aqp2Cre^+/−Nfat5^fl/fl mice that lack NFAT5 only in the collecting duct. By analyzing gene expression in the medullary and cortical regions of the kidney separately, we confirmed that the loss of NFAT5 results in kidney injury that extends beyond hypertonic areas. Renal injury correlates with the expression level of genes involved in inflammatory response, injury severity, and cytokine signaling. Thus, NFAT5 is essential not only for adapting to osmotic stress but also for its loss of function, which induces activation of inflammatory response and cytokine signaling that might affect regions with functional NFAT5 expression.

Triglyceride (TG) metabolism is a complex and highly coordinated biological process regulated by a series of genes, and its dysregulation can lead to the occurrence of disorders in lipid metabolism. However, the transcriptional regulatory mechanisms of crucial genes in TG metabolism mediated by enhancer–promoter interactions remain elusive. Here, we identified candidate enhancers regulating the Agpat2, Dgat1, Dgat2, Pnpla2, and Lipe genes in 3T3-L1 adipocytes by integrating epigenomic data (H3K27ac, H3K4me1, and DHS-seq) with chromatin three-dimensional interaction data. Luciferase reporter assays revealed that 11 enhancers exhibited fluorescence activity. The repression of enhancers using the dCas9-KRAB system revealed the functional roles of enhancers of Dgat2 and Pnpla2 in regulating their expression and TG metabolism. Furthermore, transcriptome analyses revealed that inhibition of Dgat2-En4 downregulated pathways associated with lipid metabolism, lipid biosynthesis, and adipocyte differentiation. Additionally, overexpression and motif mutation experiments of transcription factor found that two TFs, PPARG and RXRA, regulate the activity of Agpat2-En1, Dgat2-En4, and Pnpla2-En5. Our study identified functional enhancers regulating TG metabolism and elucidated potential regulatory mechanisms of TG deposition from enhancer–promoter interactions, providing insights into understanding lipid deposition.