FOXOs: signalling integrators for homeostasis maintenance. Nat Rev Mol Cell Biol. 2013;14:83-97. [PMID: 23325358 DOI: 10.1038/nrm3507]

Decoding Proteomic cross-talk between hypobaric and normobaric hypoxia: Integrative analysis of oxidative stress, cytoskeleton remodeling, and inflammatory pathways

AIMS

To investigate the differential regulation of proteomic landscapes elicited by hypobaric hypoxia (HH) and normobaric hypoxia (NH) and to shed light on the molecular cross-talk underlying pre-acclimatization strategies.

MATERIALS AND METHODS

Label-free LCMS-MS quantitative proteomics was employed to evaluate the lung tissues of SD rats (n = 6) subjected to 6 h of acute HH at 25,000 ft associated with reduced barometric pressure, 282 mmHg, and NH at 8 % FiO2.

KEY FINDINGS

Our findings indicate that NH facilitated the minimal downregulation of proteins involved in maintaining pulmonary cytoskeleton integrity, including calpain 2, vitronectin, and beta-arrestin 1, whereas HH leads to severe downregulation of these proteins, causing a greater cytoskeleton disruption. Proteins contributing to redox homeostasis such as iNOS and SOD, were upregulated in both hypoxic conditions. However, SIRT1-mediated ROS-triggered proteins, including FOXO1 and FOXO4, exhibited upregulation in HH and downregulation in NH. Other proteins, HIF-1α and IDH, were upregulated in HH compared to NH. Additionally, Hemopexin was severely downregulated in HH relative to NH.

SIGNIFICANCE

For the first time, this study uncovers the comparative proteomic analysis of two distinct pre-acclimatization interventions by employing varied hypoxia modeling strategies highlighting the key molecular mechanism involved in HH acclimatization induced by differential hypoxia simulating technique.

FOXP1 contributes to murine hematopoietic stem cell functionality

Transcription factor forkhead box P1 (FOXP1) is a key regulator of immune cell functions. We have shown that FOXP1 contributes to the expansion of human hematopoietic stem/progenitor (HSPC) and acute myeloid leukaemia cells. Here, we investigated the role of FOXP1 in early adult mouse hematopoiesis in vivo. We showed that loss of hematopoietic-specific FOXP1 expression leads to attrition of the HSC and multipotent progenitor (MPP)-1 compartment in parallel with enhancement of myeloid-biased MPP3 in adult bone marrow and fetal liver. Transplantation experiments confirmed that FOXP1-deficient bone marrow had an intrinsic reduced HSC compartment. FOXP1-deficient MPP compartments also showed enhanced proliferation with G0 phase reduction. Transcriptome analyses revealed that FOXP1-deficient HSC exhibited reduced stemness and enhanced expression of cell proliferation pathways. Thus, our current results reveal the important contribution of FOXP1 in early murine hematopoiesis through HSC maintenance, limited expansion of all MPP compartments and restriction of early myeloid commitment in vivo.

Chidamide triggers pyroptosis in T-cell lymphoblastic lymphoma/leukemia via the FOXO1/GSDME axis

BACKGROUND

T-cell lymphoblastic lymphoma/acute lymphoblastic leukemia (T-LBL/ALL) is an aggressive form of hematological malignancy associated with poor prognosis in adult patients. Histone deacetylases (HDACs) are aberrantly expressed in T-LBL/ALL and are considered potential therapeutic targets. Here, we investigated the antitumor effect of a novel HDAC inhibitor, chidamide, on T-LBL/ALL.

METHODS

HDAC1, HDAC2 and HDAC3 levels in T-LBL/ALL cell lines and patient samples were compared with those in normal controls. Flow cytometry, transmission electron microscopy, and lactate dehydrogenase release assays were conducted in Jurkat and MOLT-4 cells to assess apoptosis and pyroptosis. A specific forkhead box O1 (FOXO1) inhibitor was used to rescue pyroptosis and upregulated gasdermin E (GSDME) expression caused by chidamide treatment. The role of the FOXO1 transcription factor was evaluated by dual-luciferase reporter and chromatin immunoprecipitation assays. The efficacy of chidamide in vivo was evaluated in a xenograft mouse.

RESULTS

The expression of HDAC1, HDAC2 and HDAC3 was significantly upregulated in T-LBL/ALL. Cell viability was obviously inhibited after chidamide treatment. Pyroptosis, characterized by cell swelling, pore formation on the plasma membrane and lactate dehydrogenase leakage, was identified as a new mechanism of chidamide treatment. Chidamide triggered pyroptosis through caspase 3 activation and GSDME transcriptional upregulation. Chromatin immunoprecipitation assays confirmed that chidamide led to the increased transcription of GSDME through a more relaxed chromatin structure at the promoter and the upregulation of FOXO1 expression. Moreover, we identified the therapeutic effect of chidamide in vivo .

CONCLUSIONS

This study suggested that chidamide exerts an antitumor effect on T-LBL/ALL and promotes a more inflammatory form of cell death via the FOXO1/GSDME axis, which provides a novel choice of targeted therapy for patients with T-LBL/ALL.

Targeting oxidative stress-mediated regulated cell death as a vulnerability in cancer

Reactive oxygen species (ROS), regulators of cellular behaviors ranging from signaling to cell death, have complex production and control mechanisms to maintain a dynamic redox balance under physiological conditions. Redox imbalance is frequently observed in tumor cells, where ROS within tolerable limits promote oncogenic transformation, while excessive ROS induce a range of regulated cell death (RCD). As such, targeting ROS-mediated regulated cell death as a vulnerability in cancer. However, the precise regulatory networks governing ROS-mediated cancer cell death and their therapeutic applications remain inadequately characterized. In this Review, we first provide a comprehensive overview of the mechanisms underlying ROS production and control within cells, highlighting their dynamic balance. Next, we discuss the paradoxical nature of the redox system in tumor cells, where ROS can promote tumor growth or suppress it, depending on the context. We also systematically explored the role of ROS in tumor signaling pathways and revealed the complex ROS-mediated cross-linking networks in cancer cells. Following this, we focus on the intricate regulation of ROS in RCD and its current applications in cancer therapy. We further summarize the potential of ROS-induced RCD-based therapies, particularly those mediated by drugs targeting specific redox balance mechanisms. Finally, we address the measurement of ROS and oxidative damage in research, discussing existing challenges and future prospects of targeting ROS-mediated RCD in cancer therapy. We hope this review will offer promise for the clinical application of targeting oxidative stress-mediated regulated cell death in cancer therapy.

Psychological stress-induced systemic corticosterone directly sabotages intestinal stem cells and exacerbates colitis

Psychological stress has profound impacts on the gastrointestinal tract via the brain‒gut axis. However, its effects on intestinal stem cells (ISCs) and the resulting implication for intestinal homeostasis remain poorly understood. Here, we observed a notable reduction in both the quantity and proliferative capacity of ISCs under chronic stress conditions, driven by elevated levels of corticosterone resulting from activation of the hypothalamic‒pituitary‒adrenal (HPA) axis. Mechanistically, corticosterone directly interacts with its receptor, nuclear receptor subfamily 3 group c member 1 (NR3C1), leading to increased expression of FKBP prolyl isomerase 5 (FKBP5) in ISCs. Subsequently, FKBP5 negatively regulates AKT activation by facilitating its dephosphorylation at Ser473, ultimately enhancing nuclear translocation of forkhead box O (FoxO) and inhibiting ISC proliferative activity. Consequently, ISC dysfunction contributes to the stress-driven exacerbation of DSS-induced colitis. Collectively, these findings reveal an intrinsic brain-to-gut regulatory pathway whereby psychological stress impairs ISC activity via corticosterone elevation, providing a mechanistic explanation for stress-enhanced susceptibility to colitis.

Foxo1 directs the transdifferentiation of mouse Sertoli cells into granulosa-like cells

Sertoli and granulosa cells, the initial differentiated somatic cells in bipotential gonads, play crucial roles in directing male and female gonad development, respectively. The transcription factor Foxo1 is involved in diverse cellular processes, and its expression in gonadal somatic cells is sex-dependent. While Foxo1 is abundantly expressed in ovarian granulosa cells, it is notably absent in testicular Sertoli cells. Nevertheless, its function in gonadal somatic cell differentiation remains elusive. In this study, we find that ectopic expression of Foxo1 in Sertoli cells leads to defects in testes development. Further study uncovers that the ectopic expression of Foxo1 induces the abundant expression of Foxl2 in Sertoli cells, along with the upregulation of other female-specific genes. In contrast, the expression of male-specific genes is reduced. Mechanistic studies indicate that Foxo1 directly binds to the promoter region of Foxl2, inducing its expression. Our findings highlight that Foxo1 serves as a key regulator for the lineage maintenance of ovarian granulosa cells. This study contributes valuable insights into understanding the regulatory mechanisms governing the lineage maintenance of gonadal somatic cells.

Mitochondrial Quality Control in Ovarian Function: From Mechanisms to Therapeutic Strategies

Mitochondrial quality control plays a critical role in cytogenetic development by regulating various cell-death pathways and modulating the release of reactive oxygen species (ROS). Dysregulated mitochondrial quality control can lead to a broad spectrum of diseases, including reproductive disorders, particularly female infertility. Ovarian insufficiency is a significant contributor to female infertility, given its high prevalence, complex pathogenesis, and profound impact on women's health. Understanding the pathogenesis of ovarian insufficiency and devising treatment strategies based on this understanding are crucial. Oocytes and granulosa cells (GCs) are the primary ovarian cell types, with GCs regulated by oocytes, fulfilling their specific energy requirements prior to ovulation. Dysregulation of mitochondrial quality control through gene knockout or external stimuli can precipitate apoptosis, inflammatory responses, or ferroptosis in both oocytes and GCs, exacerbating ovarian insufficiency. This review aimed to delineate the regulatory mechanisms of mitochondrial quality control in GCs and oocytes during ovarian development. This study highlights the adverse consequences of dysregulated mitochondrial quality control on GCs and oocyte development and proposes therapeutic interventions for ovarian insufficiency based on mitochondrial quality control. These insights provide a foundation for future clinical approaches for treating ovarian insufficiency.

Targeting the Aryl Hydrocarbon Receptor to Attenuate IGF1R Signaling in Thyroid Eye Disease

Background: Thyroid eye disease (TED) is an autoimmune disorder characterized by proptosis, inflammation, and fibrosis. Elevated insulin-like growth factor 1 receptor (IGF1R) signaling in TED orbital fibroblasts (OFs) drives the proliferation and biosynthesis of hyaluronan, which causes enlargement of orbital tissue volume. The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor that regulates cellular stress responses, metabolism, and inflammation. Given its important role in regulating cellular responses, we hypothesized that activation of the AHR could limit excessive IGF1R signaling in TED OFs, offering therapeutic potential. Methods: We measured IGF1R and AHR expression levels in TED, non-TED, and non-OF controls. OF activation was analyzed using proliferation, hyaluronan accumulation, and migration assays. RNA sequencing was used to detect transcriptome-wide changes in IGF1-treated TED OFs. After gene set enrichment analysis, select gene expression changes were validated by quantitative polymerase chain reaction. OFs were treated with the AHR ligands 6-formylindolo[3,2-b]carbazole (FICZ) or tapinarof with or without IGF1. Western blotting evaluated signaling pathways impacted by AHR and IGF1R signaling. Results: TED OFs showed elevated IGF1R and AHR expression levels compared to controls. IGF1 significantly increased hyaluronan accumulation, proliferation, and migration in TED OFs compared to non-TED OFs. IGF1R signaling altered the expression of hundreds of genes controlling cell migration, proliferation, and metabolism in TED OFs. These genes included TUBA1B, TUBA1C, CRABP2 (upregulated), and IRS2 and SOD3 (downregulated). AHR activation blocked proliferation, migration, hyaluronan production, and gene expression mediated through IGF1R signaling. The AHR inhibited these pathways by reducing phosphorylation of GSK3β, an important mediator of IGF1R/β-catenin mediated signaling. Conclusions: AHR activation represents a promising therapeutic strategy for mitigating TED progression by inhibiting IGF1R signaling. Through modulation of GSK3β-mediated pathways, AHR activation may target additional pathologically relevant pathways beyond those affected by direct IGF1R inhibitors. This research provides novel insights into TED pathophysiology and offers a potential avenue for developing therapies to improve patient outcomes.

Exploring the effects of environmentally relevant concentrations of buprofezin and cadmium on tadpoles: A phenotypic and molecular analysis

With the continuous impact of human activities on the ecological environment, buprofezin and cadmium are frequently detected in soil, sediment, and aquatic environments, posing ecological risks to non-target aquatic organisms. However, limited research exists on the toxic effects and mechanisms of action of these pollutants on aquatic organisms. This study used Xenopus laevis tadpoles as model organisms to experiment with buprofezin and cadmium. Through biochemical parameters and multi omics analysis methods, the single and combined toxicity mechanisms were explored. The experiment used environmentally relevant exposure levels to monitor the growth indicators, movement parameters, oxidative stress biomarkers of tadpoles, and conducted metabolomics and transcriptomics analysis. The results indicate that cadmium inhibits the growth of tadpoles, leading to a decrease in weight, and mixed exposure has a similar effect. Under dark conditions, buprofezin and cadmium significantly alter the swimming behavior of tadpoles, decreasing distance and average speed. Moreover, tadpoles exposed to buprofezin and cadmium experienced oxidative stress, which was reflected in increased levels of malondialdehyde and decreased activities of superoxide dismutase and glutathione S-transferase. Metabolomics and transcriptomics results showed that the combined exposure group produced more differentially accumulated metabolites and differentially expressed genes than the single exposure group. These genes and substances mainly affect the energy metabolism and signal transduction processes of tadpoles. In summary, buprofezin and cadmium interfere with gene expression and alter metabolite levels in tadpoles. This study reveals the combined toxicity of buprofezin and cadmium at environmentally relevant exposure levels. The research results provide toxicological evidence for the risk assessment of environmental pollutants and offer new insights into the effects of complex mixtures.

Effects of Environmentally Friendly Aquaculture Chamber Coatings on Enzyme Activities, Histology, and Transcriptome in the Liver of Larimichthys crocea

Aquaculture vessels have emerged as a sustainable alternative to traditional offshore aquaculture. However, the biological impacts of protective coatings used for vessel interiors are still poorly understood. This study assessed acute stress responses of Larimichthys crocea to epoxy-based aquaculture coatings using actual culture (1-fold) and high-exposure (80-fold) concentrations. Liver analyses included antioxidant enzymes, histopathology, and transcriptomics over 12-96 h. Firstly, the effect of the 80-fold concentration group on the activities of catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD) was more significant in the liver of L. crocea compared to the 1-fold concentration group. Similarly, histological observations revealed that the 80-fold concentration group produced more significant pathological changes in the liver than the 1-fold concentration group, including hepatocyte damage and vacuolization. Subsequently, through high-throughput sequencing, a total of 714.02 million clean reads were obtained, with 693.71 million of these reads successfully mapped onto the reference genome of L. crocea, identifying 13,709 differentially expressed genes (DEGs). KEGG pathway enrichment analysis showed that many DEGs following coating-treated were involved in protein processing in endoplasmic reticulum, oxidative phosphorylation, cytokine-cytokine receptor interaction, FoxO signaling pathway, and toll-like receptor signaling pathway. Finally, fifteen DEGs were selected for quantitative real-time PCR (qRT-PCR) analysis, and the results showed a significant correlation with RNA-seq results, verifying the reliability and accuracy of the high-throughput sequencing data. This study preliminarily revealed the stress responses induced by aquaculture vessel coatings in L. crocea and provided fundamental data into the scientific use of coatings on aquaculture vessels.

Scorpion venom peptides enhance immunity and survival in Litopenaeus vannamei through antibacterial action against Vibrio parahaemolyticus

Introduction

Scorpion venom-derived antimicrobial peptides (AMPs) have emerged as promising candidates for combating bacterial infections owing to their potent activity and unique mechanisms of action. This study focuses on three 13-amino-acid peptides-BmKn1, BmKn2, and BmKn2-7-derived from the venom of Mesobuthus martensii. The aim is to elucidate their structural features, antibacterial efficacy, and immunomodulatory effects in Litopenaeus vannamei infected with Vibrio parahaemolyticus (VP).

Methods

The peptides were synthesized and comprehensively characterized for their amphipathic α-helical structures, net charges, and hydrophobicity. Their antibacterial mechanisms were investigated using a series of assays, including membrane permeability (inner/outer membrane disruption), membrane depolarization, reactive oxygen species (ROS) quantification, and ATPase activity measurement. In vivo challenge experiments were conducted to evaluate survival rates in L. vannamei infected with VP. Additionally, immune enzyme activities (phenoloxidase [PO], complement component 3 [C3]) and inflammatory/antimicrobial gene expression levels (TNF-α, IL-1β, TGF-β, ALF, Crus) were analyzed. Furthermore, intestinal transcriptome profiling was performed to identify the activated immune pathways.

Results

All peptides exhibited membrane-targeting activity: BmKn2-7 showed superior outer membrane penetration and depolarization, while BmKn1 was more effective in inner membrane disruption and ROS induction. In vivo, all peptides significantly improved survival rates in VP-infected shrimp (P < 0.01), with BmKn2-7 ≈ BmKn1 > BmKn2 in efficacy. Immune modulation was evident through increased PO and C3 activity (P < 0.05) and reduced expression of inflammatory cytokines and antimicrobial genes (P < 0.05). Transcriptome analysis revealed BmKn2-7 activated PPAR, AMPK, and FoxO signaling pathways.

Discussion

The amphipathic α-helical structure of these peptides is fundamental to their membrane-disruptive activity. The enhanced outer membrane targeting of BmKn2-7 likely correlates with structural modifications that optimize hydrophobicity and charge distribution. The differential efficacy in immune regulation, such as BmKn2-7's broad pathway activation versus BmKn1's selective ROS induction, indicates structure-dependent functional divergence. These findings highlight the potential of tailored scorpion venom peptides as dual-action agents against bacterial infections and immune dysregulation.

Discovery of the 2,3-Dihydrobenzopyrane-4-one as a Potent FTO Inhibitor against Obesity-Related Metabolic Diseases

The involvement of the fat mass and obesity-associated gene (FTO) in the development and advancement of metabolic disorders is widely recognized. However, the existing FTO inhibitor entacapone has been limited in clinical application due to its low potency and short plasma elimination half-life. Here, through drug library screening and in depth structure-activity relationship analysis, title compound 40, eriodictyol was identified as a potent FTO inhibitor, and showed good binding to FTO by surface plasmon resonance (SPR) and Microscale thermophoresis (MST) detection. The residues Arg96, Tyr108, Ser229, Asp233, and Glu234 of FTO are essential for binding. Meanwhile, eriodictyol attenuated obesity-related metabolic diseases by enhancing glucose metabolism pathways via the FTO-FOXO1-G6PC/PCK1 axis and increasing adipose tissue heat production for weight loss via the FTO-FOXO1-Ucp1 axis in vivo. Surprisingly, eriodictyol showed good pharmacokinetic properties and no obvious toxicity. These results could provide the reference for design of new FTO inhibitors against obesity-related metabolic diseases.

Inhibition of CHI3L1 attenuates excessive autophagy in intestinal epithelial cells to reduce the severity of necrotizing enterocolitis

Neonatal necrotizing enterocolitis (NEC) is a devastating intestinal disease that primarily affects preterm infants. Unfortunately, no specific treatment for NEC is currently available, making it crucial to further investigate its underlying mechanisms. In this study, we aimed to identify the key target gene, CHI3L1, which was significantly upregulated in the intestinal tissues of both affected children and model mice from the GEO database. CHI3L1 is known to play important roles in inflammatory and immune responses, as well as in tissue damage and repair, all of which are closely associated with the development of NEC. We conducted validations at both the cellular and animal levels, demonstrating that the inhibition or knockdown of CHI3L1 significantly reduced the severity of NEC. Mechanistic investigations revealed that the knockdown of CHI3L1 inhibited the PI3K-Akt-FoxO1 signalling pathway, alleviating excessive autophagy in intestinal epithelial cells and subsequently reducing injury and inflammatory responses. Clinical studies have revealed that elevated serum CHI3L1 expression in paediatric patients is associated with both the occurrence and severity of necrotising enterocolitis NEC, demonstrating positive correlations with the Duke Abdominal Assessment Scale (DAAS), C-reactive protein (CRP), procalcitonin (PCT), red cell distribution width (RDW), and lactate dehydrogenase (LDH) levels. In conclusion, our findings confirmed a close relationship between CHI3L1 and the occurrence and severity of NEC, suggesting that it may mitigate inflammatory responses and tissue damage by alleviating excessive autophagy in intestinal epithelial cells. Therefore, targeting CHI3L1 may be an effective strategy to combat NEC.

The dual missions of FoxO3a in inflammatory diseases: Regulation of antioxidant enzymes and involvement in programmed cell death

The transcription factor FoxO3a plays a crucial role in the process of cells adapting to various stress conditions. Multiple post - translational modifications and epigenetic mechanisms work together to precisely regulate the activity of FoxO3a, influencing its subcellular localization, stability, interactions with other proteins, DNA - binding affinity, and transcriptional regulatory capacity. Under different chemical signal stimuli and subcellular environments, the activation of FoxO3a triggered by oxidative stress can initiate diverse transcriptional programs, which are essential for the body to resist oxidative damage. In the development and progression of inflammatory diseases, FoxO3a exerts an important function by regulating the expression levels of antioxidant enzymes and participating in key physiological processes such as programmed cell death. This article comprehensively reviews the structural characteristics, mechanism of action of FoxO3a, as well as its functions in regulating antioxidant enzymes and programmed cell death. The aim is to deeply explore the potential of FoxO3a as a potential therapeutic target for preventing and treating damages such as inflammatory diseases caused by cellular stress.

Galangin reduces MPTP-induced dopamine neuron injury via the autophagy dependent-PI3K/AKT pathway

Introduction

Research has confirmed that Galangin can attenuate autophagy and protect dopaminergic neurons. This study aims to clarify whether Galangin attenuates dopaminergic neuron injury by regulating the PI3K/AKT pathway in Parkinson's disease (PD) model mice.

Methods

The study explores the mitigating effects of Galangin on PD processes by administering 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) to induce the condition. Techniques including network analysis, transcriptomic analysis, rotarod test, enzyme-linked immunosorbent assay (ELISA), qRT-PCR, western blotting, immunohistochemistry, immunofluorescence, and hematoxylin-eosin (HE) were employed to unveil the molecular changes induced by Galangin.

Results

The network pharmacological analysis showed 301 targets related to Galangin, and 2,858 genes related to PD. Galangin treatment can improve the motor coordination of PD model mice, reduce damage to neurons in the brain, improve the antioxidant capacity and reduce the inflammatory damage of brain tissue. Additionally, Galangin suppressed mRNA expression of PD markers (IL-1β, TNF-α, IL-6, SRC and PTGS2), elevated protein levels of GSH-Px, SOD, P-PI3K, P-CREB, P-AKT, TH, BDNF and P62, while decreasing α-syn, SRC, MDA, Beclin-1 and LC3B expression. Moreover, the expression of significantly different genes in the Galangin-treated group and model group analyzed by transcriptomics was basically consistent with the qRT-PCR verification results.

Conclusion

Galangin supresses Beclin-1-dependent autophagy and upregulates the PI3K/AKT signaling pathway to attenuate the neuroinflammatory injury and improve motor coordination ability in PD mice induced by MPTP.

Whole transcriptome analysis of Mycoplasma bovis-host interactions under in vitro and in vivo conditions

Mycoplasma bovis mastitis is becoming increasingly problematic for dairy cattle farming. M. bovis is inherently resistant to beta-lactam antimicrobials and no effective vaccine is available. The major constraints to developing effective control tools are limited knowledge of M. bovis virulence factors and the underlying pathogenic mechanisms. The objective of this study was to determine virulence-associated genes of M. bovis and host immune response genes expressed during the early stages of host-pathogen interactions. We conducted in vitro infection of mammary epithelial cell (MAC-T) lines and in vivo intramammary infection of dairy cows with M. bovis strain PG45 and evaluated whole transcriptome differential gene expression. A total of 614 and 7161 genes of M. bovis and bovine host cells were differentially expressed, respectively. Insertion sequence (IS) genes that are involved in transposase activity such as ISMbov1, ISMbov2, ISMbov3, and ISMbov9 were significantly upregulated, whereas protein translation-associated genes were significantly downregulated. In MAC-T cells, genes involved in apoptosis pathways and proinflammatory cytokines were significantly upregulated, whereas genes involved in cell cycle, ribosome biogenesis, and steroid biosynthesis were significantly downregulated. Genes encoding formation of neutrophil extracellular traps and proinflammatory cytokines, were significantly upregulated in the mammary gland of M. bovis challenged cows, whereas genes involved in steroid biosynthesis and metabolism were significantly downregulated. Altogether, while our findings shed light on the simultaneous transcriptional changes in M. bovis and the host during infection, further studies are required to understand a complete picture of these interactions that lead to mastitis.

Novel regulation mechanism of histone methyltransferase SMYD5 in rheumatoid arthritis

BACKGROUND

Fibroblast-like synoviocytes (FLS) are crucial for maintaining synovial homeostasis. SMYD5, a member of the histone lysine methyltransferase subfamily SMYDs, is involved in many pathological processes. This study aimed to investigate the role of SMYD5 in regulating synovial fibroblast homeostasis and the pathogenesis of rheumatoid arthritis (RA).

METHODS

Proteomic screening was conducted to assess SMYD5 expression in the synovium of patients with osteoarthritis (OA) and RA. In vitro, interleukin-1 beta (IL-1β) was used to induce proliferation and inflammation in FLS. Further, we performed loss-of-function and gain-of-function experiments to investigate the biological function of SMYD5. In vivo, adeno-associated virus (AAV) vectors carrying SMYD5 short-hairpin RNA (AAV-shSMYD5) were injected into the knee joints to knock down SMYD5 in a collagen-induced arthritis (CIA) mouse model to evaluate its role in joint damage.

RESULTS

We observed a significant elevation of SMYD5 expression in the synovial tissues of patients with RA and IL-1β-induced FLS. SMYD5 facilitated posttranslational modifications and activated downstream signaling pathways, thereby promoting proliferation and inflammation in FLS. Mechanistically, SMYD5 mediated the methylation of Forkhead box protein O1 (FoxO1), which accelerated its degradation through ubiquitination, resulting in substantial FLS proliferation. Additionally, SMYD5 promoted lactate release to activate NF-κB signaling pathways by upregulating hexokinases-2 (HK2) expression, a key glycolytic enzyme, thereby intensifying the inflammatory response in FLS. Supporting these findings, intraarticular delivery of AAV-mediated SMYD5 knockdown in the CIA mice model effectively alleviated joint swelling, bone erosion, and overall arthritis severity.

CONCLUSIONS

Together, these findings suggest that SMYD5 is a dual target for regulating synovial fibroblast homeostasis and the pathogenesis of RA. Targeting SMYD5 through local treatment strategies may provide a novel therapeutic approach for RA, particularly when combined with immunotherapy.

Reciprocal regulation between ferroptosis and STING-type I interferon pathway suppresses head and neck squamous cell carcinoma growth through dendritic cell maturation

Head and neck squamous cell carcinoma (HNSCC) presents a serious clinical challenge mainly due to its resistance to conventional therapies and its complex, immunosuppressive tumor microenvironment. While recent studies have identified ferroptosis as a new therapeutic option, its impact on the immune microenvironment in HNSCC remains controversial, which may hinder its translational application. Although the role of the stimulator of interferon genes (STING)-type I interferon (IFN-I) pathway in antitumor immune responses has been widely investigated, its relationship with ferroptosis in HNSCC has not been fully explored. In this study, we discovered that ferroptosis in HNSCC inhibited tumor growth, activated STING-IFN-I pathway and subsequently improved recruitment and maturation of dendritic cells. We further demonstrated that IFN-I could enhance ferroptosis by inhibiting xCT-glutathione peroxidase 4 (GPX4) antioxidant system. To harness this positive feedback loop, we treated HNSCC tumors with both ferroptosis inducer and STING agonist, resulting in significant tumor suppression, elevated ferroptosis levels and enhanced dendritic cell infiltration. Overall, our findings reveal a mutually regulatory relationship between ferroptosis and the intrinsic STING-IFN-I pathway, providing novel insights into immune-mediated tumor suppression and suggesting its potential as therapeutic approach in HNSCC.

Dnmt3a-mediated hypermethylation of FoxO3 promotes redox imbalance during osteoclastogenesis

Redox imbalance contributes to aberrant osteoclastogenesis and osteoporotic bone loss. In this study, we observed lower Forkhead box protein O3 (FoxO3), a transcription factor associated with cellular oxidative stress, enhanced osteoclastogenesis in osteoporosis (OP). Single-cell RNA sequencing (scRNA-seq) analysis on the human femoral head indicated that FoxO3 is widely expressed in macrophages. Furthermore, Lysm-Cre;FoxO3f/f OVX mice showed increased reactive oxygen species (ROS), enhanced osteoclastogenesis, and more bone loss than normal OVX mice. Mechanistically, we identified FoxO3 promoter methylation as a crucial factor contributing to decreased FoxO3, thereby influencing osteoclastogenesis and OC function. Intriguingly, we observed that Dnmt3a, highly expressed during osteoclastogenesis, played a pivotal role in regulating the methylation of the FoxO3 promoter. Knockdown of Dnmt3a promoted FoxO3 expression, inhibiting osteoclastogenesis and mitigating OP. Interestingly, we observed that Dnmt3a alleviated osteoclastogenesis by suppressing ROS via upregulating FoxO3 rather than inducing the dissociation of RANK and TRAF6. Collectively, this study elucidates the role and mechanism of FoxO3 in osteoclastogenesis and OP, providing a epigenetic target for the treatment of OP.

Teriparatide mitigates oxidative stress following spinal cord injury and enhances neurological recovery via the Nrf2/HO-1 signaling pathway

Introduction

Spinal Cord Injury (SCI) represents a devastating form of central nervous system trauma, where oxidative stress plays a critical role in the ensuing pathology. Targeting oxidative stress presents a viable therapeutic avenue. Teriparatide, a synthetic analog of parathyroid hormone, is conventionally utilized for osteoporosis and bone defect management. Emerging evidence suggests teriparatide's potential in modulating oxidative stress in ischemic stroke, yet its efficacy in SCI remains underexplored.

Methods

We investigated the neuroprotective effects of teriparatide in a rat spinal cord injury (SCI) model. Teriparatide was administered to animals post-injury, and functional recovery was assessed using the open field test and Basso-Beattie-Bresnahan (BBB) locomotor rating scale. Molecular analyses included evaluation of Nrf2 pathway activation and antioxidant protein expression via immunofluorescence, Western blot, and ELISA. Additionally, glutathione peroxidase (GSH-PX) activity and malondialdehyde (MDA) levels were measured using commercial assay kits.

Results

We obtained two significant results: Firstly, teriparatide treatment significantly enhanced motor function recovery post-SCI. Secondly, teriparatide upregulated Nrf2 expression, which subsequently increased the production of the antioxidant proteins HO-1 and SOD2, reduced MDA levels in spinal tissues, and boosted GSH-PX activity.

Conclusion

Our findings demonstrate that teriparatide activates the Nrf2/HO-1 antioxidant pathway, effectively mitigating oxidative damage in SCI. This repositioning of an FDA-approved osteoporosis drug presents a clinically translatable strategy for neuroprotection.

FoxO3 controls cardiomyocyte proliferation and heart regeneration by regulating Sfrp2 expression in postnatal mice

The Forkhead box O3 (FoxO3) transcription factor is crucial to controlling heart growth in adulthood, but its exact role in cardiac repair and regeneration in postnatal mice remains unclear. Here, we show that FoxO3 deficiency promotes cardiomyocyte proliferation in postnatal mice and improves cardiac function in homeostatic adult mice. Moreover, FoxO3 deficiency accelerates heart regeneration following injury in postnatal mice at the regenerative and non-regenerative stages. We reveal that FoxO3 directly promotes the expression of secreted frizzled-related protein 2 (Sfrp2) and suppresses the activation of canonical Wnt/β-catenin signaling during heart regeneration. The increased activation of β-catenin in FoxO3-deficient cardiomyocytes can be blocked by Sfrp2 overexpression. In addition, Sfrp2 overexpression suppressed cardiomyocyte proliferation and heart regeneration in FoxO3-deficient mice. These findings suggest that FoxO3 negatively controls cardiomyocyte proliferation and heart regeneration in postnatal mice at least in part by promoting Sfrp2 expression, which leading to the inactivation of canonical Wnt/β-catenin signaling.

Transcriptome Complexity Disentangled: A Regulatory Molecules Approach

Transcription factors (TFs) and microRNAs (miRNAs) are fundamental regulators of gene expression, cell state, and biological processes. This study investigated whether a small subset of TFs and miRNAs could accurately predict genome-wide gene expression. We analyzed 8895 samples across 31 cancer types from The Cancer Genome Atlas and identified 28 miRNA and 28 TF clusters using unsupervised learning. Medoids of these clusters could differentiate tissues of origin with 92.8% accuracy, demonstrating their biological relevance. We developed Tissue-Agnostic and Tissue-Aware models to predict 20,000 gene expressions using the 56 selected medoid miRNAs and TFs. The Tissue-Aware model attained anR 2 of 0.70 by incorporating tissue-specific information. Despite measuring only 1/400th of the transcriptome, the prediction accuracy was comparable to that achieved by the 1000 landmark genes. This suggests the transcriptome has an intrinsically low-dimensional structure that can be captured by a few regulatory molecules. Our approach could enable cheaper transcriptome assays and analysis of low-quality samples. It also provides insights into genes that are heavily regulated by miRNAs/TFs versus alternative mechanisms. However, model transportability was impacted by dataset discrepancies, especially in miRNA distribution. Overall, this study demonstrates the potential of a biology-guided approach for robust transcriptome representation.

In Vitro Comparative Study of Calcium Hydroxyapatite (Stiim): Conventional Saline Dilution Versus Poly-Micronutrient Dilution

Calcium hydroxylapatite (CaHA) is widely used in aesthetics for its dual role as a dermal filler and biostimulator, promoting collagen and elastin synthesis. This study evaluates the comparative potential of CaHA in conventional saline dilution versus CaHA mixed with a poly-micronutrient solution (CaHA/PMN) to enhance its biostimulatory effects. In an in vitro model, primary human fibroblasts were treated with both formulations, and cell viability and gene expression of type I collagen, elastin, FOXO3, SIRT-1, and SIRT-3 were assessed. The results demonstrated that both CaHA and CaHA/PMN treatments significantly improved cellular responses compared to the control. CaHA/PMN outperformed conventional CaHA, with greater increases in cell viability, collagen synthesis, elastin synthesis, and the expression of SIRT-1, SIRT-3, and FOXO3. These findings suggest that poly-micronutrient-enriched solutions can enhance CaHA's regenerative potential, providing a promising approach for skin rejuvenation and elasticity improvement.

Analysis of Differentially Expressed Murine miRNAs in Acute Myocardial Infarction and Target Genes Related to Heart Rate

OBJECTIVE

This study aims to investigate the expression profile of miRNAs significantly dysregulated after acute myocardial infarction (AMI) and their potential targets.

METHODS

After the establishment of a mouse model of AMI, RNA was extracted from mouse infarcted myocardium. Paired-end sequencing was then performed using the Illumina NovaSeq 6000 system to explore the expression profile of miRNAs. Target genes of downregulated differentially expressed miRNAs (DEmiRNAs) were predicted with miRanda (version 3.3a) and TargetScan (version 6.0). Cytoscape was used to construct a DEmiRNA-mRNA regulatory network to show the regulatory relationship. RT-qPCR was performed to measure miR-142a-3p expression in H2O2-treated rat cardiomyocyte H9c2 cells and heart tissues of MI rats. Cell counting kit-8 and TUNEL assays were conducted to detect H9c2 cell viability and apoptosis.

RESULTS

There were 33 differentially expressed miRNAs, of which 3 were significantly upregulated and the rest 30 were significantly downregulated. Target genes of these miRNAs were identified, and their functional enrichment was analyzed using gene ontology (GO) analysis. Importantly, target genes that can regulate heart rate and their paired upstream miRNAs attracted attention. Significant expression correlation between heart rate-related targets (Epas1, Bves, Hcn4, Cacna1e, Ank2, Slc8a1, Pde4d) and paired miRNAs (miR-142a-5p, miR-7b-5p, miR-144-3p, miR-34c-5p, miR-223-3p, miR-18a-5p) in mouse myocardial tissues was identified. MiR-142a-3p was downregulated in H9c2 cells and rat infarct tissues, and overexpressing miR-142a-3p restrains H2O2-induced H9c2 cell apoptosis.

CONCLUSION

Cardioprotective miRNAs, such as miR-142a-3p, were identified in mouse myocardial tissues, and some specific miRNA-target pairs are associated with heart rate regulation.

Single-cell RNA-seq offer new insights into the cell fate decision of the primordial germ cells

The faithful production of primordial germ cells (PGCs) in vitro opens a wide range of novel applications in reproductive biology and medicine. However, the reproducibility of PGCs culture conditions across different laboratories or breeds remains a challenge. Therefore, it is necessary to research the molecular dynamics that lead to the gradual establishment of cultured PGCs lines network. Here, the results of single-cell RNA-seq indicated that the cell cycle drove cellular heterogeneity. The active populations engaged in PGC self-renewal and the characteristics of the aging cell fate have been identified. The active self-renewal populations presented a rising expression of DNA repair genes, couple with a high proportion of cells in G1/S phase and a low frequency of cells in G2 phase. Notably, Hippo, FoxO, AMPK and MAPK pathways are active within these populations. The combination of six activator or inhibitors, targeting these active pathways, resulted in a significantly higher proliferation rate of PGCs and an increased number of cells entering the G1 and S phases. Importantly, they greatly reduced the establishment time to a minimum of 26 days and increased the efficiency of male PGC line establishment to 59 % in FS medium. Our results provided several new insights into the PGCs.

Molecular Response and Metabolic Reprogramming of the Spleen Coping with Cold Stress in the Chinese Soft-Shelled Turtle (Pelodiscus sinensis)

The Chinese soft-shelled turtle (Pelodiscus sinensis), as a type of warm-water reptile, could be induced to massive death by sharp temperature decline. Hence, the mechanism of spleen tissue responding to cold stress in the P. sinensis was investigated. The present results showed that the superoxide dismutase (SOD) activity declined from 4 to 16 days post-cold-stress (dps), while the catalase (CAT) and glutathione peroxidase (GSH-Px) activities increased, from 4 to 8 dps in the 14 °C (T14) and 7 °C (T7) stress groups. The spleen transcriptome in the T7 group and the control group (CG) at 4 dps obtained 2625 differentially expressed genes (DEGs), including 1462 upregulated and 1663 downregulated genes. The DEGs were enriched mainly in the pathways "intestinal immune network for IgA production" (Pigr, Il15ra, Tnfrsf17, Aicda, and Cd28), "toll-like receptor signaling pathway" (Mapk10, Tlr2, Tlr5, Tlr7, and Tlr8), and "cytokine-cytokine receptor interaction" (Cx3cl1, Cx3cr1, Cxcl14, Cxcr3, and Cxcr4). The metabolomic data showed that esculentic acid, tyrosol, diosgenin, heptadecanoic acid, and 7-ketodeoxycholic acid were obviously increased, while baccatin III, taurohyocholate, parthenolide, enterolactone, and tricin were decreased, in the CG vs. T7 comparison. Integrated analysis of the two omics revealed that "glycine, serine and threonine metabolism", "FoxO signaling pathway", and "neuroactive ligand-receptor interaction" were the main pathways responding to the cold stress. Overall, this work found that low temperature remarkably influenced the antioxidant enzyme activities, gene expression pattern, and metabolite profile in the spleen, indicating that immunity might be weakened by cold stress in P. sinensis.

iFlpMosaics enable the multispectral barcoding and high-throughput comparative analysis of mutant and wild-type cells

To understand gene function, it is necessary to compare cells carrying the mutated target gene with normal cells. In most biomedical studies, the cells being compared are in different mutant and control animals and, therefore, do not experience the same epigenetic changes and tissue microenvironment. The experimental induction of genetic mosaics is essential to determine a gene cell-autonomous function and to model the etiology of diseases caused by somatic mutations. Current technologies used to induce genetic mosaics in mice lack either accuracy, throughput or barcoding diversity. Here we present the iFlpMosaics toolkit comprising a large set of new genetic tools and mouse lines that enable recombinase-dependent ratiometric induction and single-cell clonal tracking of multiple fluorescently labeled wild-type and Cre-mutant cells within the same time window and tissue microenvironment. The labeled cells can be profiled by multispectral imaging or by fluorescence-activated flow cytometry and single-cell RNA sequencing. iFlpMosaics facilitate the induction and analysis of genetic mosaics in any quiescent or progenitor cell, and for any given single or combination of floxed genes, thus enabling a more accurate understanding of how induced genetic mutations affect the biology of single cells during tissue development, homeostasis and disease.

PLK3 weakens antioxidant defense and inhibits proliferation of porcine Leydig cells under oxidative stress

Aging is characterized by cellular degeneration and impaired physiological functions, leading to a decline in male sexual desire and reproductive capacity. Oxidative stress (OS) lead to testicular aging by impairing the male reproductive system, but the potential mechanisms remain unclear. In the present study, the functional status of testicular tissues from young and aged boars was compared, and the transcriptional responses of Leydig cells (LCs) to hydrogen peroxide (H2O2)-induced senescence were explored, revealing the role of OS in promoting aging of the male reproductive system. 601 differentially expressed genes (DEGs) associated with OS, cell cycle regulation, and intracellular processes were identified. These DEGs were significantly enriched in critical aging pathways, including the p53 signaling pathway, autophagy, and cellular senescence. Protein-protein interaction (PPI) network analysis unveiled 15 key genes related to cell cycle and DNA replication, with polo-like kinase 3 (PLK3) exhibiting increased expression under OS. In vitro, PLK3 knockdown significantly enhanced the viability and antioxidant capacity of LCs under OS. This study deepens our understanding of how LCs respond to OS and provides new therapeutic targets for enhancing cellular resistance to oxidative damage and promoting tissue health.

Perfluorooctane sulfonate (PFOS) induced bone loss by inhibiting FoxO1-mediated defense against oxidative stress in osteoblast

Exposure to perfluorooctane sulfonate (PFOS) has been associated with lower bone density and the occurrence of osteoporosis in human studies, but the effects and mechanisms of PFOS induces bone loss is not well understood. Our research is aimed at examining the effects of PFOS on osteoblastic activity and investigating the toxicological mechanisms of PFOS-induced bone loss. Cell proliferation, ALP activity, bone nodule formation, ROS levels, and cell apoptosis were assessed after treating osteoblasts with different concentrations of PFOS. Through transcriptome analysis, the differentially expressed genes (DEGs) were screened and the biofunctions were elucidated by Kyoto Encyclopedia of Genes and Genomes (KEGG) and The Gene Set Enrichment Analysis (GSEA). Vation of important genes and protein expression was accomplished using RT-PCR and Western blot methods, respectively. The results show that PFOS can reduce bone formation markers and improve oxidative stress and cell apoptosis. The DEGs in PFOS-treated groups were involved in multiple pathways, including FoxO, HIF-1, Rap1, Hippo, and sphingolipid signaling. FoxO1 was validated as the key gene which regulates osteogenic differentiation and redox status. Our findings suggest that PFOS reduces bone formation through FoxO1-mediated oxidative stress and apoptosis, as well as inhibition of the OPG/RANKL and FoxO1/β-catenin pathways. It will be beneficial for early intervention or treatment of PFOS-induced bone loss, highlighting the importance of regulatory measures to limit human exposure to PFOS.

The link of FOXO1 and FOXO4 transcription factors to development of the lens

BACKGROUND

The FOXOs regulate the transcription of many genes, including ones directly linked to pathways required for lens development. However, this transcription factor family has rarely been studied in the context of development, including the development of the lens. FOXO expression, regulation, and function during lens development remained unexplored.

RESULTS

In studies of the embryonic lens, we showed that both FOXO1 and FOXO4, which share many downstream targets, are expressed in a differentiation-state-specific manner, most highly in lens epithelial and differentiating cortical fiber cells. Their expression patterns and subcellular distributions suggest both shared and distinct functions. Stabilization of FOXO cytoplasmic pools involved their binding to the chaperone protein 14-3-3. FOXO association with β-catenin linked this transcription complex to fiber cell-specific gene activation. Inhibition of PI3K/Akt signaling promoted FOXO1/FOXO4 nuclear localization in lens epithelial and fiber cells and expression of the CDKi p27 in the lens epithelium where it has been linked to lens cell withdrawal from the cell cycle and initiation of the lens differentiation program. We showed that FOXO1 transcriptional activation is required for the induction of p27 when Akt signaling is blocked, demonstrating the linearity of the PI3K/Akt/FOXO1/p27 pathway.

CONCLUSIONS

PI3K/Akt signaling regulates FOXO-dependent lens cell differentiation.

Methods to Study Structure and Dynamics of FOXO Proteins

FOXOs are highly dynamic transcription factors consisting of one conserved DNA-binding domain (forkhead domain) as well as intrinsically disordered regions (IDRs) at the N- and C-termini. These IDRs are essential and regulate transcriptional activity of FOXOs by serving as interaction platform for cofactors. Furthermore, the IDRs are involved in intra- and intermolecular homeotypic and heterotypic interactions between FOXOs and in turn mediate FOXO auto-inhibition and condensate formation. Here, we describe generalizable methods to study the structure and dynamics of FOXO proteins in vitro using a combination of biophysical techniques, in particular nuclear magnetic resonance spectroscopy. These methods can serve as a blueprint for the investigation of other IDR-containing transcription factors.

Measuring FOXO Nuclear Shuttling Dynamics by Fluorescence Microscopy

FOXO transcription factors respond to a number of different stresses by shuttling from the cytoplasm to the nucleus where they upregulate hundreds of target genes with diverse cellular functions. The cellular consequences of FOXO activation are both stress and cell-type specific. Recent evidence suggests that one way in which FOXO dictates stress-specific outcomes is through distinct nuclear/cytoplasmic shuttling dynamics. Here we outline methods for measuring FOXO nuclear shuttling dynamics using fluorescence-based reporters.

Simultaneous binding of quercetin and catechin to FOXO3 enhances IKKα transcription inhibition and suppression of oxidative stress-induced acute alcoholic liver injury in rats

INTRODUCTION

Oxidative stress is one of the major contributors to acute alcoholic liver injury (AALI), which is a common alcoholic liver disease. Quercetin and catechin are flavonoid antioxidants present in plant foods and possess chemopreventive and chemotherapeutic activities. Quercetin and catechin are often included in the same meal and ingested together. While they show cooperative actions against oxidative damage, the underlying mechanisms behind their counteracting effects against oxidative stress-induced AALI remain poorly understood.

OBJECTIVES

The aim of this study was to understand the mechanism underlying the enhanced antioxidant effect of quercetin-catechin combination to alleviate AALI in rats.

METHODS

The ethanol (EtOH)-treated rats and H2O2-treated liver cells were used to demonstrate the enhanced antioxidant effect of quercetin and catechin. Then we used RNA-sequencing to compare quercetin alone, catechin alone and quercetin-catechin combination and then identified the critical role of IKKα combining with gene silencing and overexpression techniques. Its transcription factor, FOXO3 was found through yeast one-hybrid assay, luciferase reporter assay, EMSA and ChIP assay. Finally, the interaction between quercetin, catechin and FOXO3 was verified through molecular docking, UV-Vis absorption spectroscopy, fluorescence spectroscopy, and CD spectroscopy.

RESULTS

The study demonstrated the enhanced antioxidant effect of a quercetin-catechin combination in EtOH-treated rats and in H2O2-treated liver cells. Quercetin and catechin cooperatively inhibited IKKα/p53 pathway and activated Nrf2 signaling pathway. IKKα was a critical negative regulator in their joint action. FOXO3 bound to IKKα promoter to regulate IKKα transcription. Quercetin and catechin influenced FOXO3-IKKα binding through attaching directly to FOXO3 at different sites and altering FOXO3's secondary structures.

CONCLUSION

Our study revealed the mechanism of quercetin and catechin against oxidative stress-induced AALI through jointly interacting with transcription factor. This research opens new vistas for examining the joint effect of therapeutics towards functional proteins and confirms the chemopreventive effects of multiple flavonoids via co-regulation.

Nanoengineered cargo with targeted in vivo Foxo3 gene editing modulated mitophagy of chondrocytes to alleviate osteoarthritis

Mitochondrial dysfunction in chondrocytes is a key pathogenic factor in osteoarthritis (OA), but directly modulating mitochondria in vivo remains a significant challenge. This study is the first to verify a correlation between mitochondrial dysfunction and the downregulation of the FOXO3 gene in the cartilage of OA patients, highlighting the potential for regulating mitophagy via FOXO3 gene modulation to alleviate OA. Consequently, we developed a chondrocyte-targeting CRISPR/Cas9-based FOXO3 gene-editing tool (FoxO3) and integrated it within a nanoengineered 'truck' (NETT, FoxO3-NETT). This was further encapsulated in injectable hydrogel microspheres (FoxO3-NETT@SMs) to harness the antioxidant properties of sodium alginate and the enhanced lubrication of hybrid exosomes. Collectively, these FoxO3-NETT@SMs successfully activate mitophagy and rebalance mitochondrial function in OA chondrocytes through the Foxo3 gene-modulated PINK1/Parkin pathway. As a result, FoxO3-NETT@SMs stimulate chondrocytes proliferation, migration, and ECM production in vitro, and effectively alleviate OA progression in vivo, demonstrating significant potential for clinical applications.

Distinct UPR and Autophagic Functions Define Cell-Specific Responses to Proteotoxic Stress in Microglial and Neuronal Cell Lines

Autophagy is a catabolic process involved in different cellular functions. However, the molecular pathways governing its potential roles in different cell types remain poorly understood. We investigated the role of autophagy in the context of proteotoxic stress in two central nervous system cell types: the microglia-like cell line BV2 and the neuronal-like cell line N2a. Proteotoxic stress, induced by proteasome inhibition, produced early apoptosis in BV2 cells, due in part to a predominant activation of the PERK-CHOP pathway. In contrast, N2a cells showcased greater resistance and robust induction of the IRE1α-sXbp1 arm of the UPR. We also demonstrated that proteotoxic stress activated autophagy in both cell lines but with different kinetics and cellular functions. In N2a cells, autophagy restored cellular proteostasis, while in BV2 cells, it participated in regulating phagocytosis. Finally, proteotoxic stress predominantly activated the mTORC2-AKT-FOXO1-β-catenin pathway in BV2 cells, while N2a cells preferentially induced the PDK1-AKT-FOXO3 axis. Collectively, our findings suggest that proteotoxic stress triggers cell-specific responses in microglia and neurons, with different physiological outcomes.

Integrated Analysis of Transcriptome and Metabolome in the Brain After Cold Stress of Red Tilapia During Overwintering

Cold stress during overwintering is considered a bottleneck problem limiting the development of the red tilapia (Oreochromis spp.) industry, and the regulation mechanism is currently not well understood. In this study, the fish (initial weight: 72.71 ± 1.32 g) were divided into the cold stress group (cold) and the control (normal) group. In the control group, the water temperature was maintained at 20 °C, which is basically consistent with the overwintering water temperature in greenhouses of local areas. In the cold group, the water temperature decreased from 20 °C to 8 °C by 2 °C per day during the experiment. At the end of the experiment, the levels of fish serum urea nitrogen, glucose, norepinephrine, alkaline phosphatase, total bilirubin, and total cholesterol in the cold group changed significantly compared with that in the control group (P < 0.05). Then transcriptome sequencing and LC-MS metabolome of brain tissue were further employed to obtain the mRNA and metabolite datasets. We found that the FoxO signaling pathway and ABC transporters played an important role by transcriptome-metabolome association analysis. In the FoxO signaling pathway, the differentially expressed genes were related to cell cycle regulation, apoptosis and immune-regulation, and oxidative stress resistance and DNA repair. In the ABC transporters pathway, the ATP-binding cassette (ABC) subfamily abca, abcb, and abcc gene expression levels, and the deoxycytidine, L-lysine, L-glutamic acid, L-threonine, ornithine, and uridine metabolite contents changed. Our results suggested that the cold stress may promote apoptosis through regulation of the FoxO signaling pathway. The ABC transporters may respond to cold stress by regulating amino acid metabolism. The results provided a comprehensive understanding of fish cold stress during overwintering, which will facilitate the breeding of new cold-resistant varieties of red tilapia in the future.

AKT kinases as therapeutic targets

AKT, or protein kinase B, is a central node of the PI3K signaling pathway that is pivotal for a range of normal cellular physiologies that also underlie several pathological conditions, including inflammatory and autoimmune diseases, overgrowth syndromes, and neoplastic transformation. These pathologies, notably cancer, arise if either the activity of AKT or its positive or negative upstream or downstream regulators or effectors goes unchecked, superimposed on by its intersection with a slew of other pathways. Targeting the PI3K/AKT pathway is, therefore, a prudent countermeasure. AKT inhibitors have been tested in many clinical trials, primarily in combination with other drugs. While some have recently garnered attention for their favorable profile, concern over resistance and off-target effects have continued to hinder their widespread adoption in the clinic, mandating a discussion on alternative modes of targeting. In this review, we discuss isoform-centric targeting that may be more effective and less toxic than traditional pan-AKT inhibitors and its significance for disease prevention and treatment, including immunotherapy. We also touch on the emerging mutant- or allele-selective covalent allosteric AKT inhibitors (CAAIs), as well as indirect, novel AKT-targeting approaches, and end with a briefing on the ongoing quest for more reliable biomarkers predicting sensitivity and response to AKT inhibitors, and their current state of affairs.

Pseudokinase STK40 promotes TH1 and TH17 cell differentiation by targeting FOXO transcription factors

Inappropriate CD4+ T helper (TH) cell differentiation leads to progression of inflammatory and autoimmune diseases, yet the regulatory mechanisms governing stability and activity of transcription factors controlling TH cell differentiation remain elusive. Here, we describe how pseudokinase serine threonine kinase 40 (STK40) facilitates TH1/TH17 differentiation under pathological conditions. STK40 in T cells is dispensable for immune homeostasis in resting mice. However, mice with T cell-specific deletion of STK40 exhibit attenuated symptoms of experimental autoimmune encephalomyelitis and colitis, accompanied by diminished TH1 and TH17 cell differentiation. Mechanistically, STK40 facilitates K48-linked polyubiquitination and proteasomal degradation of FOXO1/4 through promoting their interaction with E3 ligase COP1. Inhibition of FOXO4 or FOXO1, respectively, restores differentiation potential of STK40-deficient TH1/TH17 cells. Together, our data suggest a crucial role of STK40 in TH1 and TH17 cell differentiation, thereby enabling better understanding of the molecular regulatory network of CD4+ T cell differentiation and providing effective targets for the treatment of autoimmune diseases.

Maternal dietary olive oil protects diabetic rat offspring from impaired uterine decidualization

INTRODUCTION

Maternal diabetes increases the risk of adverse maternal, perinatal and offspring outcomes. This study aimed to address whether alterations in uterine decidualization are programmed in the prepubertal offspring from diabetic rats fed diets enriched or not in extra virgin olive oil (EVOO).

METHODS

Control and mild pregestational diabetic female rats (F0) were mated with control males and fed diets enriched or not with 6 % EVOO during pregnancy. Offspring (F1) were evaluated on postnatal day 30, after induction of uterine decidualization (PMSG 50 IU- hCG 50 IU). Signaling pathways involved in decidualization, including prolactin, PPAR and mTOR pathways as well as microRNAs (miRs) regulating these pathways were evaluated by Western blot or qPCR in the decidualized uteri.

RESULTS

The offspring from diabetic rats evidenced reduced prolactin and prolactin receptor levels in the decidualized uteri. Additionally, these tissues showed increased PPARγ levels and reduced levels of its negative regulators miR-19b and miR-155. MiR-21, a microRNA that targets both PPARα and mTOR pathway regulators was reduced, whereas PPARα, PTEN and FOXO1 mRNA levels were increased in the decidualized uteri of the offspring from diabetic rats. The mTOR pathway activity was reduced in the decidualized uteri of the offspring from diabetic rats. Most of the observed alterations were prevented by the EVOO-enriched maternal diet.

DISCUSSION

Impaired pathways relevant to decidualization are programmed in the uteri of prepubertal offspring from diabetic dams, alterations capable of being prevented by maternal diets enriched in EVOO.

The molecular consequences of FOXF1 missense mutations associated with alveolar capillary dysplasia with misalignment of pulmonary veins

BACKGROUND

Alveolar capillary dysplasia with misalignment of pulmonary veins (ACD/MPV) is a fatal congenital lung disorder strongly associated with genomic alterations in the Forkhead box F1 (FOXF1) gene and its regulatory region. However, little is known about how FOXF1 genomic alterations cause ACD/MPV and what molecular mechanisms are affected by these mutations. Therefore, the effect of ACD/MPV patient-specific mutations in the FOXF1 gene on the molecular function of FOXF1 was studied.

METHODS

Epitope-tagged FOXF1 constructs containing one of the ACD/MPV-associated mutations were expressed in mammalian cell lines to study the effect of FOXF1 mutations on protein function. EMSA binding assays and luciferase assays were performed to study the effect on target gene binding and activation. Immunoprecipitation followed by SDS‒PAGE and western blotting were used to study protein‒protein interactions. Protein phosphorylation was studied using phos-tag western blotting.

RESULTS

An overview of the localization of ACD/MPV-associated FOXF1 mutations revealed that the G91-S101 region was frequently mutated. A three-dimensional model of the forkhead DNA-binding domain of FOXF1 showed that the G91-S101 region consists of an α-helix and is predicted to be important for DNA binding. We showed that FOXF1 missense mutations in this region differentially affect the DNA binding of the FOXF1 protein and influence the transcriptional regulation of target genes depending on the location of the mutation. Furthermore, we showed that some of these mutations can affect the FOXF1 protein at the posttranscriptional level, as shown by altered phosphorylation by MST1 and MST2 kinases.

CONCLUSION

Missense mutations in the coding region of the FOXF1 gene alter the molecular function of the FOXF1 protein at multiple levels, such as phosphorylation, DNA binding and target gene activation. These results indicate that FOXF1 molecular pathways may be differentially affected in ACD/MPV patients carrying missense mutations in the DNA-binding domain and may explain the phenotypic heterogeneity of ACD/MPV.

Identification of a FOXO gene and its roles in anti-WSSV infection through regulation of Dicers and Argos in Macrobrachium nipponense

Forkhead box O (FOXO) proteins are a subgroup of the forkhead family of transcription factors that play important roles in the immune response. In this study, we cloned and identified a FOXO gene named MnFOXO from Macrobrachium nipponense. The full-length cDNA of MnFOXO is 2086 bp and contains a 1302 bp open reading frame, which encodes 433 amino acids. MnFOXO consists of five low-complexity regions and a conserved DNA-binding domain (forkhead domain). Evolutionary analyses indicate that MnFOXO proteins cluster with FOXO proteins from crustaceans. Tissue distribution analysis showed that MnFOXO was expressed in all detected tissues, with relatively higher expression levels in the intestine, eyestalks, stomach, and hemocytes than in the hepatopancreas, gills, and heart. The expression levels of MnFOXO in the hepatopancreas and intestine were significantly up-regulated in M. nipponense infected with white spot syndrome virus (WSSV) at 24 and 48 h. Furthermore, knockdown of MnFOXO increased the expression of WSSV envelope protein VP28 during WSSV infection. Further studies showed that knockdown of the MnFOXO gene in M. nipponense inhibited the synthesis of Dicers (MnDicer1, MnDicer2) and Argonautes (MnArgo1, MnArgo2) during WSSV invasion. These findings suggest that MnFOXO positively regulates the expression of Dicers and Argos, and inhibits the expression of VP28. This study provides new evidence for understanding the role of FOXO in antiviral innate immunity in crustaceans.

Blockade of forkhead box protein O1 signaling alleviates primary sclerosing cholangitis-induced sarcopenia in mice model

AIMS

Primary sclerosing cholangitis (PSC) is a cholestatic liver disease that affects the hepatic bile ducts, leading to hepatic inflammation and fibrosis. PSC can also impact skeletal muscle through the muscle-liver axis, resulting in sarcopenia, a complication characterized by a generalized loss of muscle mass and strength. The underlying mechanisms and therapy of PSC-induced sarcopenia are not well understood, but one potential regulator is the transcription factor forkhead box protein O1 (FOXO1), which is involved in the ubiquitin proteasome system. Thus, the aim of this study is to assess the pharmacological potential of FOXO1 inhibition for treating PSC-induced sarcopenia.

MATERIALS AND METHODS

To establish diet-induced PSC model, we provided mice with a 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) diet for 4 weeks. Mice were intramuscularly injected with AS1842856 (AS), a FOXO1 inhibitor, at a dose of 3.5 mg/kg twice a week for last two weeks. C2C12 myotubes with cholic acid (CA) or deoxycholic acid (DCA) were treated with AS.

KEY FINDINGS

We observed a decrease in muscle size and performance in DDC-fed mice with upregulated expression of FOXO1 and E3 ligases such as ATROGIN1 and MuRF1. We found that myotube diameter and MyHC protein level were decreased by CA or DCA in C2C12 myotubes, but treatment of AS reversed these reductions. We observed that intramuscular injection of AS effectively mitigates DDC diet-induced sarcopenia in a rodent PSC model.

SIGNIFICANCE

Our study suggests that a FOXO1 inhibitor could be a potential leading therapeutic drug for relieving PSC-induced sarcopenia.

ESC-sEVs alleviate non-early-stage osteoarthritis progression by rejuvenating senescent chondrocytes via FOXO1A-autophagy axis but not inducing apoptosis

Osteoarthritis (OA) is a common joint degenerative disease which currently lacks satisfactory disease-modifying treatments. Oxidative stress-mediated senescent chondrocytes accumulation is closely associated with OA progression, which abrogates cartilage metabolism homeostasis by secreting senescence-associated secretory phenotype (SASP) factors. Numerous studies suggested mesenchymal stem cells-derived small extracellular vesicles (MSC-sEVs) have been regarded as promising candidates for OA therapy. However, MSC-sEVs were applied before the occurrence of cartilage degeneration or at early-stage OA, while in clinical practice, most OA patients who present with pain are already in non-early-stage. Recently, embryonic stem cells-derived sEVs (ESC-sEVs) have been reported to possess powerful anti-aging effects. However, whether ESC-sEVs could attenuate non-early-stage OA progression remains unknown. In this study, we demonstrated ESC-sEVs ameliorated senescent phenotype and cartilage destruction in both mechanical stress-induced non-early-stage posttraumatic OA and naturally aged mice. More importantly, we found ESC-sEVs alleviated senescent phenotype by rejuvenating aged chondrocytes but not inducing apoptosis. We also provided evidence that the FOXO1A-autophagy axis played an important role in the anti-aging effects of ESC-sEVs. To promote clinical translation, we confirmed ESC-sEVs reversed senescent phenotype in ex-vivo cultured human end-stage OA cartilage explants. Collectively, our findings reveal that ESC-sEVs-based therapy is of high translational value in non-early-stage OA treatment.

Transcriptomic Analysis of Hippocampus abdominalis Larvae Under High Temperature Stress

OBJECTIVES

Acute temperature stress was explored in Hippocampus abdominalis through a comprehensive RNA-seq analysis.

METHODS

RNA-seq was conducted on 20-day-old H. abdominalis after 24 h of temperature stress. Four experimental conditions were established: a control group (18 °C) and three temperature treatment groups (21, 24, and 27 °C).

RESULTS

Seahorse larvae were found to be unaffected by 21 °C and 24 °C and were able to survive for short periods of time during 24 h of incubation, whereas mortality approached 50% at 27 °C. The sequencing process produced 75.63 Gb of high-quality clean data, with Q20 and Q30 base percentages surpassing 98% and 96%, respectively. A total of 141, 333, and 1598 differentially expressed genes were identified in the 21, 24, and 27 °C groups vs. a control comparison group, respectively. Notably, the number of up-regulated genes was consistently higher than that of down-regulated genes across all comparisons. Gene Ontology functional annotation revealed that differentially expressed genes were predominantly associated with metabolic processes, redox reactions, and biosynthetic functions. In-depth KEGG pathway enrichment analysis demonstrated that down-regulated genes were significantly enriched in pathways related to steroid biosynthesis, terpenoid backbone biosynthesis, spliceosome function, and DNA replication. Up-regulated genes were enriched in pathways associated with the FoxO signaling pathway and mitophagy (animal). The results indicated that temperature stress induced extensive changes in gene expression in H. abdominalis, involving crucial biological processes such as growth, biosynthesis, and energy metabolism.

CONCLUSIONS

This study provided key molecular mechanisms in the response of H. abdominalis to temperature stress, offering a strong basis for future research aimed at understanding and mitigating the effects of environmental stressors on marine species.

Multi-scalar data integration decoding risk genes for chronic kidney disease

BACKGROUND

Chronic Kidney Disease (CKD) impacts over 10% of the global population, and recent advancements in high-throughput analytical technologies are uncovering the complex physiology underlying this condition. By integrating Genome-Wide Association Studies (GWAS), RNA sequencing (RNA-seq/RNA array), and single-cell RNA sequencing (scRNA-seq) data, our study aimed to explore the genes and cell types relevant to CKD traits.

METHODS

GWAS summary data for end-stage renal failure (ESRD) and decreased eGFR (CKD) with or without diabetes and (micro)proteinuria were obtained from the GWAS Catalog and the UK Biobank (UKB) database. Two gene Expression Omnibus (GEO) transcriptome datasets were used to establish glomerular and tubular gene expression differences between CKD patients and healthy individuals. Two scRNA-seq datasets were utilized to obtain the expression of key genes at the single-cell level. The expression profile, differentially expressed genes (DEGs), gene-gene interaction, and pathway enrichment were analysed for these CKD risk genes.

RESULTS

A total of 779 distinct SNPs were identified from GWAS across different CKD traits, involving 681 genes. While many of these risk genes are specific to the CKD traits of renal failure, decreased eGFR, and (micro)proteinuria, they share common pathways, including extracellular matrix (ECM). ECM modeling was enriched in upregulated glomerular and tubular DEGs from CKD kidneys compared to healthy controls, with the expression of relevant collagen genes, such as COL1A2, prevalent in fibroblasts/myofibroblasts. Additionally, immune responses, including T cell differentiation, were dysregulated in CKD kidneys. The late podocyte signature gene THSD7A was enriched in podocytes but downregulated in CKD. We also highlighted that the regulated risk genes of CKD are mainly expressed in tubular cells and immune cells in the kidney.

CONCLUSIONS

Our integrated analysis highlight the genes, pathways, and relevant cell types associational with the pathogenesis of kidney traits, as a basis for further mechanistic studies to understand the pathogenesis of CKD.

Colostrum-derived extracellular vesicles: potential multifunctional nanomedicine for alleviating mastitis

Bovine mastitis is an infectious disease that causes substantial economic losses to the dairy industry worldwide. Current antibiotic therapy faces issues of antibiotic misuse and antimicrobial resistance, which has aroused concerns for both veterinary and human medicine. Thus, this study explored the potential of Colo EVs (bovine colostrum-derived extracellular vesicles) to address mastitis. Using LPS-induced murine mammary epithelial cells (HC11), mouse monocyte macrophages (RAW 264.7), and a murine mastitis model with BALB/C mice, we evaluated the safety and efficacy of Colo EVs, in vivo and in vitro. Colo EVs had favorable biosafety profiles, promoting cell proliferation and migration without inducing pathological changes after injection into murine mammary glands. In LPS-induced murine mastitis, Colo EVs significantly reduced inflammation, improved inflammatory scores, and preserved tight junction proteins while protecting milk production. Additionally, in vitro experiments demonstrated that Colo EVs downregulated inflammatory cytokine expression, reduced inflammatory markers, and attenuated NF-κB pathway activation. In summary, we inferred that Colo EVs have promise as a therapeutic approach for mastitis treatment, owing to their anti-inflammatory properties, potentially mediated through the NF-κB signaling pathway modulation.

Hepatic WDR23 proteostasis mediates insulin homeostasis by regulating insulin-degrading enzyme capacity

Maintaining insulin homeostasis is critical for cellular and organismal metabolism. In the liver, insulin is degraded by the activity of the insulin-degrading enzyme (IDE). Here, we establish a hepatic regulatory axis for IDE through WDR23-proteostasis. Wdr23KO mice have increased IDE expression, reduced circulating insulin, and defective insulin responses. Genetically engineered human cell models lacking WDR23 also increase IDE expression and display dysregulated phosphorylation of insulin signaling cascade proteins, IRS-1, AKT2, MAPK, FoxO, and mTOR, similar to cells treated with insulin, which can be mitigated by chemical inhibition of IDE. Mechanistically, the cytoprotective transcription factor NRF2, a direct target of WDR23-Cul4 proteostasis, mediates the enhanced transcriptional expression of IDE when WDR23 is ablated. Moreover, an analysis of human genetic variation in WDR23 across a large naturally aging human cohort in the US Health and Retirement Study reveals a significant association of WDR23 with altered hemoglobin A1C (HbA1c) levels in older adults, supporting the use of WDR23 as a new molecular determinant of metabolic health in humans.

Novel Therapeutic Target for ALI/ARDS: Forkhead Box Transcription Factors

ALI/ARDS can be a pulmonary manifestation of a systemic inflammatory response or a result of overexpression of the body's normal inflammatory response involving various effector cells, cytokines, and inflammatory mediators, which regulate the body's immune response through different signalling pathways. Forkhead box transcription factors are evolutionarily conserved transcription factors that play a crucial role in various cellular processes, such as cell cycle progression, proliferation, differentiation, migration, metabolism, and DNA damage response. Transcription factors control protein synthesis by regulating gene transcription levels, resulting in diverse biological outcomes. The Fox family plays a role in activating or inhibiting the expression of various molecules related to ALI/ARDS through phosphorylation, acetylation/deacetylation, and control of multiple signalling pathways. An in-depth analysis of the integrated Fox family's role in ALI/ARDS can aid in the development of potential diagnostic and therapeutic targets for the condition.

Variants in tubule epithelial regulatory elements mediate most heritable differences in human kidney function

Kidney failure, the decrease of kidney function below a threshold necessary to support life, is a major cause of morbidity and mortality. We performed a genome-wide association study (GWAS) of 406,504 individuals in the UK Biobank, identifying 430 loci affecting kidney function in middle-aged adults. To investigate the cell types affected by these loci, we integrated the GWAS with human kidney candidate cis-regulatory elements (cCREs) identified using single-cell assay for transposase-accessible chromatin sequencing (scATAC-seq). Overall, 56% of kidney function heritability localized to kidney tubule epithelial cCREs and an additional 7% to kidney podocyte cCREs. Thus, most heritable differences in adult kidney function are a result of altered gene expression in these two cell types. Using enhancer assays, allele-specific scATAC-seq and machine learning, we found that many kidney function variants alter tubule epithelial cCRE chromatin accessibility and function. Using CRISPRi, we determined which genes some of these cCREs regulate, implicating NDRG1, CCNB1 and STC1 in human kidney function.

Macrophages play a crucial role in vascular smooth muscle cell coverage

The microvascular system consists of two cell types: endothelial and mural (pericytes and vascular smooth muscle cells; VSMCs) cells. Communication between endothelial and mural cells plays a pivotal role in the maintenance of vascular homeostasis; however, in vivo molecular and cellular mechanisms underlying mural cell development remain unclear. In this study, we found that macrophages played a crucial role in TGFβ-dependent pericyte-to-VSMC differentiation during retinal vasculature development. In mice with constitutively active Foxo1 overexpression, substantial accumulation of TGFβ1-producing macrophages and pericytes around the angiogenic front region was observed. Additionally, the TGFβ-SMAD pathway was activated in pericytes adjacent to macrophages, resulting in excess ectopic α-smooth muscle actin-positive VSMCs. Furthermore, we identified endothelial SEMA3C as an attractant for macrophages. In vivo neutralization of SEMA3C rescued macrophage accumulation and ectopic VSMC phenotypes in the mice, as well as drug-induced macrophage depletion. Therefore, macrophages play an important physiological role in VSMC development via the FOXO1-SEMA3C pathway.