The FASEB Journal最新文献

Ubiquitin-mediated proteolysis plays a critical role in meiotic cell-cycle regulation and must be tightly controlled to achieve correct chromosome segregation. While the role of E2 ubiquitin-conjugating enzymes in mitosis is well-documented, their functions in oocyte meiosis remain largely unexplored. In this study, we identified UBE2D3 as the most highly expressed E2 enzyme in mouse oocytes, which is essential for proper meiotic division. UBE2D3 depletion caused (metaphase I) MI arrest and Cyclin B1 accumulation, whereas its overexpression led to reduced Cyclin B1 levels, kinetochore-microtubule (K-MT) mis-attachments, spindle assembly checkpoint (SAC) dysfunction, and increased aneuploidy. Notably, UBE2D3 upregulation in oocytes from aged mice contributed to age-related meiotic defects, which were partially reversed by UBE2D3 knockdown or Cyclin B1 overexpression. This study underscores the importance of the UBE2D3-Cyclin B1 axis in maintaining meiotic fidelity and highlights its potential as a therapeutic target for improving oocyte quality and fertility in aged females.

RETRACTION: D. Thuringer, G. Jego, G. Wettstein, O. Terrier, L. Cronier, N. Yousfi, S. Hébrard, A. Bouchot, A. Hazoumé, A.-L. Joly, M. Gleave, M. Rosa-Calatrava, E. Solary, and C. Garrido, “Extracellular HSP27 Mediates Angiogenesis Through Toll-Like Receptor 3,” The FASEB Journal 27, no. 10 (2013): 4169-4183, https://doi.org/10.1096/fj.12-226977.

The above article, published online on 26 June 2013 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the authors; the journal Editor-in-Chief, Loren E. Wold; the Federation of American Societies for Experimental Biology; and Wiley Periodicals LLC. The retraction has been agreed upon following an investigation into concerns raised by a third party which revealed inappropriate image panel duplications between this (Figure 3A) and another article published previously in a different scientific context. The investigation also revealed that the western blot panels of Figure 4E were later reused in a publication of the same author group, depicting different experimental conditions. Due to the number and the level of errors identified in the published figures, the authors and the editors have lost confidence in the presented data and consider the conclusions substantially compromised.

EXPRESSION OF CONCERN: A. Iervolino, D. Trisciuoglio, D. Ribatti, A. Candiloro, A. Biroccio, G. Zupi, D. Del Bufalo, “Bcl-2 Overexpression in Human Melanoma Cells Increases Angiogenesis Through VEGF mRNA Stabilization and HIF-1-mediated Transcriptional Activity,” The FASEB Journal 16, no. 11 (2002): 1453-1455, https://doi.org/10.1096/fj.02-0122fje.

This Expression of Concern is for the above article, published online on July 01, 2002, in Wiley Online Library (http://onlinelibrary.wiley.com/), and has been issued by agreement between the journal Editor-in-Chief, Loren E. Wold; the Federation of American Societies for Experimental Biology; and Wiley Periodicals LLC. A third party reported concerns of duplication and manipulation in Figure 1, and splicing and duplication in Figures 2B and 5A. These concerns were confirmed by the journal and publisher. Author D. Del Bufalo responded to an inquiry by the journal on behalf of the authors, but the authors were not able to supply original data due to the length of time that has elapsed since publication. The Expression of Concern has been agreed on because the evidence of image manipulation and duplication calls into question the validity of the data in Figures 1, 2, and 5, which cannot be confirmed due to the lack of original data. Author D. Del Bufalo disagrees with the Expression of Concern. All other authors did not respond to our notice regarding the Expression of Concern.

Alzheimer's disease (AD) is the most prevalent age-related neurodegenerative disorder, mainly characterized by amyloid β (Aβ) accumulation in the brain. Numerous new agents are currently undergoing clinical trials as disease-modifying therapies (DMTs) targeting Aβ. ALZ-801 is a promising candidate DMT for AD, with a phase 3 trial of ALZ-801 ongoing specifically for apolipoprotein E (APOE) ε4 homozygous patients with early-stage AD. This study aimed to examine the effects of ALZ-801 on Aβ assembly and explore its toxicological profile. Thioflavin T (ThT) assays and two imaging modalities—transmission electron microscopy (TEM) and high-speed atomic force microscopy (HS-AFM)—were used to evaluate ALZ-801's effects on Aβ assembly. To assess the effect of ALZ-801 on Aβ₄₂-induced cytotoxicity, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays and lactate dehydrogenase (LDH) assays were performed. ThT assays revealed increased lag time and decreased fluorescence in the presence of ALZ-801, confirming inhibition of Aβ₄₂ fibril formation, as confirmed by TEM. Real-time observation using HS-AFM revealed that ALZ-801 inhibited the formation of Aβ₄₂ fibril from low-molecular-weight (LMW)-Aβ₄₂ in the presence of Aβ₄₂ seeds. HS-AFM also revealed that globular aggregates from LMW-Aβ₄₂ were significantly larger with ALZ-801, with few fibrils noted. MTT and LDH assays indicated that ALZ-801 prevented LMW-Aβ₄₂-induced cytotoxicity but did not reduce cytotoxicity induced by high-molecular-weight-Aβ₄₂. ALZ-801 can inhibit Aβ₄₂ aggregation by preventing both nucleus formation and fibril elongation, while promoting large globular oligomer formation, and can significantly reduce LMW-Aβ₄₂-induced cytotoxicity. These findings underscore the potential of ALZ-801 as an effective DMT for APOE ε4 homozygous patients with AD.

Lung bacterial infections, including hospital-acquired pneumonia, remain a serious problem for public health. Endothelial cell (EC) exposure to heat-killed Staphylococcus aureus (HKSA) represents a clinical scenario of high titers of killed bacterial particles present in the host after antibiotic therapy, which triggers inflammatory cascades, cytokine storms, and EC dysfunction leading to acute lung injury (ALI). GPR68 is a member of the proton-sensing G protein-coupled receptor family. Acting as a pH sensor, GPR68 becomes activated upon pH reduction and contributes to pathologic cell responses by activating ER stress and unfolded protein response. This study investigated the role of GPR68 in HKSA-induced EC dysfunction and HKSA-induced ALI. HKSA robustly increased GPR68 mRNA levels in human pulmonary EC and directly stimulated GPR68 activity. A selective GPR68 small molecule inhibitor, OGM-8345, attenuated HKSA-induced EC permeability and protected cell junction integrity. OGM-8345 inhibited HKSA-induced activation of inflammatory genes TNF-α, IL-6, IL-8, IL-1β, and CXCL5 and decreased cytokine secretion by HKSA-challenged EC. Co-treatment with the GPR68 activator Ogerin or medium acidification to pH 6.5 augmented HKSA-induced EC dysfunction, which was rescued by OGM-8345. Intratracheal HKSA injection increased vascular leak and lung inflammation in mice which were monitored by lung Evans blue extravasation, increased cell and protein count in bronchoalveolar lavage, and mRNA expression of inflammatory genes. ALI and barrier dysfunction was attenuated by OGM-8345. We show for the first time the role of GPR68 in mediating HKSA-induced lung injury and the strong potential for OGM-8345 as a therapeutic treatment of bacterial pathogen-induced ALI associated with tissue acidification.

Glucagon-like peptide-1 (GLP-1), derived from enteroendocrine cells, is a pivotal hormone crucial for blood glucose regulation. Menin, encoded by the MEN1 gene and known for its tumor suppressor role, is abundantly expressed in the intestine. Previous research has demonstrated that acute Men1 excision reverses preexisting glucose intolerance in high-fat diet-fed mice. However, its impact on GLP-1 expression in enteroendocrine cells has not been investigated. In the present study, both the knockdown of Men1 and the administration of the MI-463 menin inhibitor increased GLP-1 expression in glucose-stimulated STC-1 cells. Additionally, administering MI-463 to obese mice significantly elevated GLP-1 levels in both ileal epithelial cells and serum. Mechanistically, menin inhibition enhanced the nuclear accumulation of β-catenin, allowing it to bind TCF7L2, thereby increasing glucagon gene (Gcg) transcription. Furthermore, compared with control mice, mice with intestinal epithelial cell-specific Men1 knockdown exhibited significant improvements in glucose tolerance under fat challenge, which was correlated with elevated GLP-1 levels. These findings suggest that menin-mediated regulation of GLP-1 expression may be an important mechanism through which menin inhibiton alleviates type 2 diabetes.

Intestinal epithelial cells (IECs) are dynamically regulated by luminal contents, including dietary ingredients, food additives, and microbiota-derived metabolites. Although sugar substitutes are commonly used as food additives for their sweet taste and lower calorie content, there is limited experimental evidence regarding their potential to drive gut remodeling. In this study, we designed experimental models for short-term consumption of erythritol, a natural sugar alcohol widely used as a sugar substitute, and investigated its effects on gut remodeling and the underlying mechanisms. Our findings indicate that erythritol consumption induces hyperplasia in tuft cells (TCs) and goblet cells (GCs), as well as enhances the activity of intestinal stem cells–increases in expression levels of leucine-rich repeat containing G protein-coupled receptor 5 (Lgr5), the key intestinal stem cell marker, in the number of proliferating stem cells, and facilitation of their differentiation into villi cells–while maintaining the number of Lgr5⁺ intestinal stem cells. Notably, the enhanced stem cell activity was observed even in Trpm5 knockout mice, suggesting that it is mechanistically independent of TC hyperplasia. Instead, we demonstrated the functional involvement of the gut microbiota, as antibiotic treatment abolished this effect, and fecal material transfer from erythritol-consumed mice replicated the enhancement of stem cell activity in recipient mice. Furthermore, we identified acetate as the metabolite responsible for enhancing stem cell activity. These findings suggest the functional decoupling of TC hyperplasia and the enhancement of stem cell activity, providing a potential therapeutic avenue for gut epithelial diseases.

Harbinger transposase-derived 1 proteins (HARBI1s) play important roles in plant growth, development, and response to abiotic stress. OsHARBI1-1 has been identified as a gene encoding HARBI1-1 protein in rice and has been shown to be responsive to Cadmium (Cd) stress. However, the function of OsHARBI1-1 protein under heavy metal stress remains unclear. In this study, the function of a novel rice Cd-responsive gene, OsHARBI1-1, under Cd stress was characterized by heterologous expression in yeast. The heterologous expression OsHARBI1-1 conferred yeast with increased tolerance to Cd. In addition, the yeast cells expressing OsHARBI1-1 exhibited enhanced tolerance to Congo red and exhibited an increase in cell wall thickness under Cd stress, suggesting a potential correlation between increased Cd tolerance and cell wall thickness in the transgenic yeast. When OsHARBI1-1 was expressed in ∆yap1 or ∆yap1∆ycf1 yeast mutants, there was no significant difference in the tolerance of transgenic yeast to Cd and Congo red, as well as in cell wall thickness compared to the control. Meanwhile, the expression of cell wall integrity (CWI) genes and catalase genes in transgenic yeast was up-regulated in a YAP1-dependent manner under Cd or Congo red stress. The above facts supported the inference that OsHARBI1-1 may counteract Cd toxicity by enhancing the expression of YAP1, thereby increasing the thickness of the cell wall and activating the expression of catalase genes.

Retinal neovascularization impairs visual function and is a hallmark of several neovascular eye diseases, including retinopathy of prematurity (ROP) and proliferative diabetic retinopathy (PDR). Current treatments include intravitreal injections of anti-vascular endothelial growth factor (VEGF) biologics, but these therapeutics are often accompanied by high treatment burden and resistance to therapy. Prior studies indicate that APE1/Ref-1, a multifunctional protein with both endonuclease (APE1) and redox-mediated transcriptional regulatory activity (Ref-1), activates multiple pro-angiogenic and pro-inflammatory signaling pathways by chemically reducing key cysteine residues in transcription factors, thereby activating them. Here, we investigated the previously unexplored role of Ref-1 in retinal neovascularization. We demonstrate that Ref-1 is highly expressed in endothelial cells in human PDR and in the oxygen-induced retinopathy (OIR) mouse model of retinal neovascularization. Ref-1 is also highly expressed in microglia and astrocytes in OIR. A small molecule Ref-1 redox inhibitor, APX2009, decreased retinal neovascularization in OIR after systemic delivery. In vitro, hypoxic endothelial cells did not exhibit upregulation of Ref-1 but rather increased Ref-1 nuclear localization. APX2009 decreased hypoxic endothelial cell proliferation and HIF-1α transcriptional activation. Thus, Ref-1 redox activity may be a novel therapeutic target for the treatment of retinal neovascularization, making APX2009 a promising systemic therapeutic approach for the treatment of vascular retinopathies such as ROP and PDR.

Exercise impinges on almost all physiological processes at an organismal level and is a potent intervention to treat various diseases. Exercise performance is well established to display diurnal rhythm, peaking during the late active phase. However, the underlying molecular/metabolic factors and mitochondrial energetics that possibly dictate time-of-day exercise capacity remain unknown. Here, we have unraveled the importance of diurnal variation in mitochondrial functions as a determinant of skeletal muscle exercise performance. Our results show that exercise-induced muscle metabolome and mitochondrial energetics are distinct at ZT3 and ZT15. Importantly, we have elucidated key diurnal differences in mitochondrial functions that are well correlated with disparate time-of-day-dependent exercise capacity. Providing causal mechanistic evidence, we illustrate that loss of Sirtuin4 (SIRT4), a well-known mitochondrial regulator, abrogates mitochondrial diurnal variation and consequently abolishes time-of-day-dependent muscle output. Therefore, our findings unequivocally demonstrate the pivotal role of baseline skeletal muscle mitochondrial functions in dictating diurnal exercise capacity.