The FASEB Journal最新文献

Rasola, A., Far, D.F., Hofman, P. and Rossi, B. (1999), Lack of internucleosomal DNA fragmentation is related to C1⁻ efflux impairment in hematopoietic cell apoptosis. The FASEB Journal, 13: 1711–1723. https://doi.org/10.1096/fasebj.13.13.1711

The authors noticed that in Figure 1A, the “MAN” and “SOR” labels of the cytofluorimetric diagrams were erroneously transposed. Therefore, the correct wording is MAN, 10.12 (percentage of apoptotic cells, in the lower right quadrant of the diagram) in the upper panel; SOR, 10.64 (percentage of apoptotic cells, in the lower right quadrant of the diagram), in the lower panel. The original images are no longer available and cannot be reproduced. The authors apologize for this error, which does not change the results of the article.

Moreover, the authors want to highlight that the diagrams labeled as Ctr, MAN, and NaCl of the same Figure 1A were also used in Figure 2D (where they are indicated as Ctr, MAN 4h, and NaCl 4h), as both are from the same representative cytofluorimetric experiment.

Pyroptosis plays a pivotal role in airway epithelial inflammation during the progression of asthma. This study aimed to explore the influence and mechanisms of opa-interacting protein 5 antisense RNA1 (OIP5-AS1) and growth arrest-specific transcript 5 (GAS5) on pyroptosis in asthmatic models. Pyroptosis was induced in Dermatophagoides pteronyssinus 1 (Der p1)-exposed 16HBE cells and ovalbumin (OVA)-challenged rats. Subsequently, pyroptosis and its related molecular mechanisms were investigated. Our results indicated that GATA1, OIP5-AS1, GAS5, and LIFR were upregulated, while miR-136-5p was downregulated in the patients and experimental models of asthma. OIP5-AS1/GAS5 knockdown repressed NLRP3 inflammasome-mediated pyroptosis in 16HBE cells. Mechanistically, OIP5-AS1/GAS5 sponged miR-136-5p to enhance LIFR expression and subsequently activated NF-κB pathway. OIP5-AS1, GAS5, or LIFR-mediated induction of pyroptosis was abrogated by miR-136-5p mimics or NF-κB inhibitors (BAY11-7082). Finally, GATA1 transcriptionally activated OIP5-AS1/GAS5 to trigger pyroptosis, thereby driving asthma progression in vivo and in vitro. In conclusion, OIP5-AS1/GAS5 transcriptionally activated by GATA1 promoted NLRP3 inflammasome-mediated pyroptosis via the modulation of miR-136-5p/LIFR/NF-κB axis and consequently resulted in airway inflammation in asthma. Our results may provide novel therapeutic strategies for asthma.

Aspartame is the most common artificial sweetener and a famous sweet-taste receptor agonist. Macrophages are essential in the antibacterial system to maintain the stability of the intestinal environment. Recently, the sweet taste receptor has been found in macrophages. However, the effects of aspartame on macrophage phagocytosis in the gastrointestinal tract are little known. The current study sought to assess the influence of aspartame intake on the scavenging activity of mice to low-dose Escherichia coli infection and related mechanisms. Firstly, no inflammatory response or pathological injury was observed in the intestines of mice after oral administration of aspartame (25–100 mg/kg, i.g.) for 2 weeks. Subsequently, aspartame intake was found to enhance the scavenging activity of mice to low-dose E. coli infection. Similarly, aspartame dose-dependent strengthened the ability of RAW264.7 cells to phagocytose GFP-E.coli J96. Further mechanism evaluation reflected that aspartame could enhance macrophage phagocytosis, migration, and rearrangement via PLCβ-2/Ca²⁺/PKCβ/Rho A/ROCK1 pathway caused by sweet taste receptor activation. In conclusion, the present study, for the first time, demonstrated that aspartame could enhance the scavenging activity of mice to low-dose E. coli infection via strengthening macrophage phagocytic function through activating sweet taste receptor. It is then suggested that aspartame may affect the antibacterial activity of human gastrointestinal macrophages, and further studies need to validate these effects.

H3K27 acetylation (H3K27ac) is crucial in muscle development as it regulates gene expression. Dysregulation of H3K27ac level has been linked to muscle-related diseases such as Duchenne muscular dystrophy, yet the mechanisms through which H3K27ac influences myogenic differentiation are not fully understood. Here, we utilized the SGC-CBP30 drug, a CBP/p300 bromodomain inhibitor, to reduce H3K27ac level and investigated its effect on myogenic differentiation of porcine skeletal muscle satellite cells. The results demonstrated an increased H3K27ac level during normal muscle satellite cell differentiation. We found that the addition of SGC-CBP30 resulted in a reduced level of H3K27ac based on ATAC-seq and CUT&Tag data. Our analysis revealed that a cluster characterized by reduced levels of H3K27ac and increased levels of H3K27me3 was enriched with motifs corresponding to Bach2, MafK, and Fosl2 transcription factors. Furthermore, knockdown of Bach2, MafK, and Fosl2 produced a similar suppression effect on myogenic differentiation. Taken together, our study contributes to a better understanding of how H3K27ac influences myogenic differentiation.

Insulin is secreted by the pancreatic β-cells and regulates glucose uptake. Endoplasmic reticulum (ER) stress is known to induce insulin resistance. Identifying novel compounds, which can ameliorate ER stress and insulin resistance may be beneficial in the treatment of diabetes. Since treatment with compounds sourced from edible plants is relatively safe, this study aimed to identify a plant-derived potential compound attenuating insulin resistance. In the present study, we identified apigenin as an effective compound for ameliorating ER stress and insulin resistance. It attenuated ER stress-induced cell death and hepatic insulin resistance and improved abnormal glucose tolerance in a db/db diabetic model. The molecular mechanism of apigenin involved direct binding to β-tubulin and improving tubulin stability, thereby recovering insulin resistance and developing diabetes. To our knowledge, no known antidiabetic drugs are yet known to target β-tubulin. Edible plants containing apigenins, such as onions, oranges, and parsley, have been consumed since a long time. Therefore, the use of natural edible plants as a source may offer a safe strategy for the prevention of diabetes.

Diabetic nephropathy (DN) is a severe microvascular complication of diabetes that poses a significant burden to global health. This investigation aims to illustrate the functional role of CD3D and its relevant mechanisms in DN progression. The pivotal genes between the GSE47183 and GSE30528 datasets were identified using bioinformatics methods. The effects of CD3D silencing on renal damage, inflammatory response, and lipid metabolism were validated in DN mice. Furthermore, the impacts of CD3D knockdown on cell viability, apoptotic rate, inflammation, and lipid levels were investigated in HK-2 cells under high glucose (HG) conditions. Additionally, RO8191 was employed to investigate the role of CD3D in the JAK/STAT pathway in HG-treated cells. A total of 5 focal genes were identified through bioinformatics and were found to be upregulated in renal tissues from DN mice. CD3D silencing mitigated pathological damage to kidneys, reduced inflammatory response, and decreased lipid accumulation in DN mice. HG stimulation restrained viability, increased apoptosis, promoted the release of inflammatory cytokines, and affected expressions of hallmarks related to lipid metabolism in HG-treated cells; these changes were partially abolished by CD3D knockdown. Mechanistically, CD3D downregulation ameliorated HG-induced injury in HK-2 cells by blocking the JAK/STAT pathway. This study underscores that CD3D silencing has significant potential as a promising candidate in the treatment of DN.

CD59 is a cell-surface inhibitor of the terminal step in the complement cascade. However, in addition to its complement inhibitory function, a non-canonical role of CD59 in pancreatic beta cells has been identified. Two recently discovered intracellular alternative splice forms of CD59, IRIS-1 and IRIS-2, are involved in insulin exocytosis through interactions with SNARE-complex components. In mice, the CD59 gene has undergone duplication and to further explore the role of CD59 in insulin secretion, blood glucose homeostasis was studied in a CD59 double knockout (CD59abKO) mouse model. However, no phenotypic deviation related to insulin secretion or blood glucose homeostasis was observed for the CD59abKO mice. Instead, a CD59ba hybrid transcript formed as a consequence of the mutation induced to generate the model was identified. This hybrid transcript is expressed in pancreatic islets of the CD59abKO mice and is comprised of the remaining exons of the two CD59 genes spliced together. Similar to canonical CD59, the CD59ba hybrid was found to be glycosylated and present on the cell surface when exogenously expressed in INS-1 832/13 cells. Furthermore, INS-1 832/13 cells over-expressing the mouse CD59ba hybrid retained normal insulin secretion following siRNA-mediated knockdown of canonical CD59. Hence, although the CD59ba hybrid has lost the complement inhibitory function, the intracellular insulin secretory function remains. These results provide further information concerning the structural requirements of CD59 in its intracellular role relative to its role as a complement inhibitor. It also highlights the importance of carefully assessing plausible consequences of induced mutations in research models.

The sperm ability to fertilize involves the regulation of ATP levels. Because inside cells, ATP is complexed with Mg²⁺ ions, changes in ATP levels result in changes in intracellular Mg²⁺ concentration ([Mg²⁺]_i), which can be followed using intracellular Mg²⁺ sensors such as Mag-520. In this work, we tested conditions known to decrease sperm ATP such as starvation and capacitation. As expected, in these conditions [Mg²⁺]_i increased in all cell compartments. In contrast, when ATP increases, such as adding nutrients to starved sperm, [Mg²⁺]_i significantly decreases in all compartments. On the other hand, when the acrosome reaction was induced, either with progesterone or with ionomycin, [Mg²⁺]_i was differentially regulated in the head and mid-piece. While Mag-520 fluorescence increased in the sperm mid-piece, it decreased in the head. These changes were observed in capacitated as well as in starved sperm but not in sperm incubated in conditions that do not support capacitation. Changes in [Mg²⁺]_i were still observed when the sperm were incubated in high extracellular Mg²⁺ suggesting that this decrease is not due to Mg²⁺ efflux. Interestingly, the progesterone and ionomycin effects on [Mg²⁺]_i were abolished on sperm incubated in Ca²⁺-free media. Altogether, these results indicate that [Mg²⁺]_i is regulated in sperm during capacitation and acrosomal reaction, and suggest that these measurements can serve to evaluate ATP levels in real time.

Autosomal dominant polycystic kidney disease (ADPKD) is caused by mutations in PKD1 and PKD2, encoding polycystin-1 (PC1) and polycystin-2 (PC2), which are required for the regulation of the renal tubular diameter. Loss of polycystin function results in cyst formation. Atypical forms of ADPKD are caused by mutations in genes encoding endoplasmic reticulum (ER)-resident proteins through mechanisms that are not well understood. Here, we investigate the function of DNAJB11, an ER co-chaperone associated with atypical ADPKD. We generated mouse models with constitutive and conditional Dnajb11 inactivation and Dnajb11-deficient renal epithelial cells to investigate the mechanism underlying autosomal dominant inheritance, the specific cell types driving cyst formation, and molecular mechanisms underlying DNAJB11-dependent polycystic kidney disease. We show that biallelic loss of Dnajb11 causes cystic kidney disease and fibrosis, mirroring human disease characteristics. In contrast to classical ADPKD, cysts predominantly originate from proximal tubules. Cyst formation begins in utero and the timing of Dnajb11 inactivation strongly influences disease severity. Furthermore, we identify impaired PC1 cleavage as a potential mechanism underlying DNAJB11-dependent cyst formation. Proteomic analysis of Dnajb11- and Pkd1-deficient cells reveals common and distinct pathways and dysregulated proteins, providing a foundation to better understand phenotypic differences between different forms of ADPKD.

Platelet activation plays a critical role in thrombosis and hemostasis. Several pathophysiological situations lead to hemolysis, resulting in the liberation of free ferric iron-containing hemin. Hemin has been shown to activate platelets and induce thrombo-inflammation. Classical antiplatelet therapy failed to prevent hemin-induced platelet activation. Thus, the aim of the present study was to characterize the mechanism of hemin-induced platelet death (ferroptosis). We evaluated the in vitro effect of hemin on platelet activation, signaling, oxylipins, and plasma membrane destruction using light transmission aggregometry, ex vivo thrombus formation, multiparametric flow cytometry, micro-UHPLC mass spectrometry for oxylipin profiling, and scanning ion conductance microscopy (SICM). We found that hemin induces platelet cell death indicated by increased ROS levels, phosphatidyl serine (PS) exposure, and loss of mitochondrial membrane potential (ΔΨm). Further, hemin causes lipid peroxidation and generation of distinct oxylipins, which strongly affects plasma membrane integrity leading to generation of platelet-derived microvesicles. Interestingly, hemin-dependent platelet death (ferroptosis) is specifically regulated by the subtilisin-like proprotein convertase furin. In summary, platelet undergo a non-apoptotic cell death mediated by furin. Inhibition of furin may offer a therapeutic strategy to control hemin-induced thrombosis and thrombo-inflammation at a site of hemolysis.