Bromodomain Protein Inhibition Protects ß-Cells from Cytokine-Induced Death and Dysfunction via Antagonism of NF-κB Pathway.

Cytokine-induced ß-cell apoptosis is a major pathogenic mechanism in type 1 diabetes (T1D). Despite significant advances in understanding its underlying mechanisms, few drugs have been translated to protect ß-cells in T1D. Epigenetic modulators such as bromodomain-containing BET (bromo- and extra-terminal) proteins are important regulators of immune responses. Pre-clinical studies have demonstrated a protective effect of BET inhibitors in an NOD (non-obese diabetes) mouse model of T1D. However, the effect of BET protein inhibition on ß-cell function in response to cytokines is unknown. Here, we demonstrate that I-BET, a BET protein inhibitor, protected ß-cells from cytokine-induced dysfunction and death. In vivo administration of I-BET to mice exposed to low-dose STZ (streptozotocin), a model of T1D, significantly reduced ß-cell apoptosis, suggesting a cytoprotective function. Mechanistically, I-BET treatment inhibited cytokine-induced NF-kB signaling and enhanced FOXO1-mediated anti-oxidant response in ß-cells. RNA-Seq analysis revealed that I-BET treatment also suppressed pathways involved in apoptosis while maintaining the expression of genes critical for ß-cell function, such as Pdx1 and Ins1. Taken together, this study demonstrates that I-BET is effective in protecting ß-cells from cytokine-induced dysfunction and apoptosis, and targeting BET proteins could have potential therapeutic value in preserving ß-cell functional mass in T1D.

[MiR-224-5p overexpression inhibits oxidative stress by regulating the PI3K/Akt/FoxO1 axis to attenuate hypoxia/reoxygenation-induced cardiomyocyte injury].

OBJECTIVES: To investigate the regulatory role of miRNA-224-5p in hypoxia/reoxygenation (H/R) -induced H9c2 cardiomyocyte injury. METHODS: Plasma samples were collected from 160 patients with acute myocardial infarction and 80 healthy controls(HC) to measure miRNA-224-5p levels and other biochemical parameters. In cultured H9c2 cells with H/R injury, the effects of transfection with miR-224-5p mimics or a negative control sequence on cell viability, malondialdehyde (MDA) content, and superoxide dismutase 2 (SOD2) and lactate dehydrogenase (LDH) activities were tested. Dual luciferase reporter gene assay was performed to verify the targeting relationship between miR-224-5p and PTEN. Bioinformatics methods were used to analyze the potential mechanisms of the target genes. The expression of miRNA-224-5p in the treated cells was detected with qRT-PCR, the protein expressions of PTEN, Bcl-2, Bax, cleaved caspase-3, SOD2, p-PI3K/PI3K, p-Akt/Ak and p-FoxO1/FoxO1 were determined using Western blotting, and cell apoptosis was analysed with flow cytometry. RESULTS: The levels of blood glucose, C-reactive protein, CK, CK-MB and cTnI were significantly higher in the AMI group compared with the HC group (P < 0.05). The expression level of miR-224-5p was significantly lowered in patients with STEMI and NSTEMI and in H9c2 cells with H/R injury. The viability of H9c2 cells decreased time-dependently following H/R injury. PTEN was a target gene of miR-224-5p, and the PI3K/Akt pathway was the most significantly enriched pathway. H9c2 cells with H/R injury showed significantly decreased SOD2 activity, increased LDH activity and MDA content, increased cell apoptosis, decreased protein expression levels of p-PI3K, p-Akt, p-FoxO1, SOD2, and Bcl-2, and increased expressions of PTEN, Bax, and cleaved caspase-3. These changes were obviously attenuated by trasnfection of the cells with miR-224-5p mimics prior to H/R exposure. CONCLUSION: MiR-224-5p overexpression upregulates the expression of the antioxidant gene SOD2 through the PI3K/Akt/FoxO1 axis to relieve H/R-induced oxidative stress and reduce apoptosis of H9c2 cells.

The effect of Toxoplasma gondii infection on galectin-9 expression in decidual macrophages contributing to dysfunction of decidual NK cells during pregnancy.

BACKGROUND: Toxoplasma gondii infection causes adverse pregnancy outcomes by affecting the expression of immunotolerant molecules in decidual immune cells. Galectin-9 (Gal-9) is widely expressed in decidual macrophages (dMφ) and is crucial for maintaining normal pregnancy by interacting with the immunomodulatory protein T-cell immunoglobulin and mucin domain-containing molecule 3 (Tim-3). However, the effects of T. gondii infection on Gal-9 expression in dMφ, and the impact of altered Gal-9 expression levels on the maternal-fetal tolerance function of decidual natural killer (dNK) cells, are still unknown. METHODS: Pregnancy outcomes of T. gondii-infected C57BL/6 and Lgals9-/- pregnant mice models were recorded. Expression of Gal-9, c-Jun N-terminal kinase (JNK), phosphorylated JNK (p-JNK), and Forkhead box protein O1 (FOXO1) was detected by western blotting, flow cytometry or immunofluorescence. The binding of FOXO1 to the promoter of Lgals9 was determined by chromatin immunoprecipitation-polymerase chain reaction (ChIP-PCR). The expression of extracellular signal-regulated kinase (ERK), phosphorylated ERK (p-ERK), cAMP-response element binding protein (CREB), phosphorylated CREB (p-CREB), T-box expressed in T cells (T-bet), interleukin 10 (IL-10), and interferon gamma (IFN-γ) in dNK cells was assayed by western blotting. RESULTS: Toxoplasma gondii infection increased the expression of p-JNK and FOXO1 in dMφ, resulting in a reduction in Gal-9 due to the elevated binding of FOXO1 with Lgals9 promoter. Downregulation of Gal-9 enhanced the phosphorylation of ERK, inhibited the expression of p-CREB and IL-10, and promoted the expression of T-bet and IFN-γ in dNK cells. In the mice model, knockout of Lgals9 aggravated adverse pregnancy outcomes caused by T. gondii infection during pregnancy. CONCLUSIONS: Toxoplasma gondii infection suppressed Gal-9 expression in dMφ by activating the JNK/FOXO1 signaling pathway, and reduction of Gal-9 contributed to dysfunction of dNK via Gal-9/Tim-3 interaction. This study provides new insights for the molecular mechanisms of the adverse pregnancy outcomes caused by T. gondii.

RNF213 promotes Treg cell differentiation by facilitating K63-linked ubiquitination and nuclear translocation of FOXO1.

Autoreactive CD4+ T helper cells are critical players that orchestrate the immune response both in multiple sclerosis (MS) and in other neuroinflammatory autoimmune diseases. Ubiquitination is a posttranslational protein modification involved in regulating a variety of cellular processes, including CD4+ T cell differentiation and function. However, only a limited number of E3 ubiquitin ligases have been characterized in terms of their biological functions, particularly in CD4+ T cell differentiation and function. In this study, we found that the RING finger protein 213 (RNF213) specifically promoted regulatory T (Treg) cell differentiation in CD4+ T cells and attenuated autoimmune disease development in an FOXO1-dependent manner. Mechanistically, RNF213 interacts with Forkhead Box Protein O1 (FOXO1) and promotes nuclear translocation of FOXO1 by K63-linked ubiquitination. Notably, RNF213 expression in CD4+ T cells was induced by IFN-ß and exerts a crucial role in the therapeutic efficacy of IFN-ß for MS. Together, our study findings collectively emphasize the pivotal role of RNF213 in modulating adaptive immune responses. RNF213 holds potential as a promising therapeutic target for addressing disorders associated with Treg cells.

A biochemical assessment of apoptosis-inducing impact of Salinomycin in combination with ciprofloxacin on human leukemia KG1-a stem-like cells in the presence and absence of insulin.

BACKGROUND: Acute Myeloid Leukemia (AML) is a fast-developing invading cancer that impacts the blood and bone marrow, marked by the rapid proliferation of abnormal white blood cells. Chemotherapeutic agents, a primary treatment for AML, encounter clinical limitations such as poor solubility and low bioavailability. Previous studies have highlighted antibiotics as effective in inducing cancer cell death and potentially preventing metastasis. Besides, insulin is known to activate the PI3K/Akt pathway, often disrupted in cancers, leading to enhanced cell survival and resistance to apoptosis. In light of the above-mentioned points, we examined the anti-cancer impact of antibiotics Ciprofloxacin (CP) and Salinomycin (SAL) and their combination on KG1-a cells in the presence and absence of insulin. METHODS: This was accomplished by exposing KG1-a cells to different doses of CP and SAL alone, in combination, and with or without insulin for 24-72 h. Cell viability was evaluated using the MTT assay. Besides, apoptotic effects were examined using Hoechst staining and Annexin-V/PI flow cytometry. The expression levels of Bax, p53, BIRC5, Akt, PTEN, and FOXO1 were analyzed through Real-Time PCR. RESULTS: CP and SAL demonstrated cytotoxic and notable pro-apoptotic impact on KG1-a cells by upregulating Bax and p53 and downregulating BIRC5, leading to G0/G1 cell cycle arrest and prevention of the PI3K-Akt signaling pathway. Our findings demonstrated that combination of CP and SAL promote apoptosis in the KG1-a cell line by down-regulating BIRC5 and Akt, as well as up-regulating Bax, p53, PTEN, and FOXO1. Additionally, the findings strongly indicated that insulin effectively mitigates apoptosis by enhancing Akt expression and reducing FOXO1 and PTEN gene expression in the cells treated with CP and SAL. CONCLUSION: Our findings showed that the combined treatment of CP and SAL exhibit a strong anti-cancer effect on leukemia KG1-a cells. Moreover, it was discovered that the PI3K-Akt signaling can be a promising target in leukemia treatment particularly in hyperinsulinemia condition.

[Porphyromonas gingivalis persisters induce the immuno-inflammatory responses in macrophages by upregulating the forkhead box1 signaling pathway].

Objective: To investigate the effects of Porphyromonas gingivalis (Pg) persisters (Ps) on immuno-inflammatory responses in macrophages, and to explore the underlying mechanisms. Methods: Pg cells were cultured to the stationary phase (72 h), and subsequently treated by high concentration of metronidazole at 100 mg/L, amoxicillin at 100 mg/L and the combination of them for different time period, named as metronidazole group, amoxicillin group and (metronidazole+amoxicillin) group. Pg cells without treatment were used as Blank control. The survival profile of PgPs cells was measured by colony-forming unit assay. The living state of PgPs was observed by Live/Dead staining. Then, Pg and metronidazole-treated PgPs (M-PgPs) were used to treat macrophages, named as Pg group and M-PgPs group. Transmission electron microscopy (TEM) was used to observe the bacteria in the macrophages. The expression levels of proinflammatory cytokines in macrophages were determined by real-time fluorescence quantitative PCR and enzyme-linked immunosorbent assay. The location of forkhead box transcription factor 1 (FOXO1) was detected by confocal immunofluorescence microscopy. After inhibiting or enhancing the FOXO1 expressions using inhibitors (Fi) or activators (Fa) respectively, the macrophages were treated with Pg and M-PgPs, divided as Blank group, Pg group, M-PgPs group, Fi group, (Fi+Pg) group, (Fi+M-PgPs) group, Fa group, (Fa+Pg) group and (Fa+M-PgPs) group. Then, the expression pattens of proinflammatory cytokines were assessed. Results: Remarkable number of lived PgPs was observed, both in planktonic culture and Pg biofilms either treated with metronidazole, amoxicillin or both, and those persisters could form new colonies. Pg and M-PgPs were able to enter into the macrophages and the protein expression levels of interleukin (IL)-1ß, IL-6, IL-8 and tumor necrosis factor-α (TNF-α) [Pg group: (2 392±188), (162±29), (5 558±661), (789±155) µg/L; M-PgPs group: (2 415±420), (155±3), (5 732±782), (821±176) µg/L] were significantly upregulated than those in Blank group [(485±140), (21±9), (2 332±87), (77±7) µg/L] (P<0.01). Moreover, Pg and M-PgPs could facilitate the nuclear translocation and accumulation of FOXO1. In addition, the relative mRNA expression levels of FOXO1, B-cell lymphoma 6 and Krüppel-like factor 2 were upregulated when compared to Blank group (P<0.05). Furthermore, the protein expression levels of IL-1ß, IL-6, IL-8 and TNF-α in Fi+Pg group [(1 081±168), (70±8), (1 976±544), (420±47) µg/L] were remarkably lower than Pg group [(4 411±137), (179±6), (5 161±929), (934±24) µg/L] (P<0.05). Similarly, the protein expression levels of IL-1ß, IL-6, IL-8 and TNF-α in Fi+M-PgPs group [(1 032±237), (74±10), (1 861±614), (405±32) µg/L] were remarkably lower than M-PgPs group [(4 342±314), (164±17), (4 438±1 374), (957±25) µg/L] (P<0.05). On the contrary, the protein expression levels of IL-1ß, IL-6, IL-8 and TNF-α in Fa+Pg group [(8 198±1 825), (431±28), (8 919±650), (2 186±301) µg/L] and Fa+M-PgPs group [(8 159±2 627), (475±26), (8 995±653), (2 255±387) µg/L] were significantly higher than Pg group and M-PgPs group, respectively (P<0.05). Conclusions: PgPs are highly tolerant to metronidazole and amoxicillin. The M-PgPs could enhance the immuno-inflammatory responses in macrophages by upregulating the FOXO1 signaling pathway, while this effect exhibits no significant difference with Pg.

Calorie restriction activates a gastric Notch-FOXO1 pathway to expand ghrelin cells.

Calorie restriction increases lifespan. Among the tissue-specific protective effects of calorie restriction, the impact on the gastrointestinal tract remains unclear. We report increased numbers of chromogranin A-positive (+), including orexigenic ghrelin+ cells, in the stomach of calorie-restricted mice. This effect was accompanied by increased Notch target Hes1 and Notch ligand Jag1 and was reversed by blocking Notch with DAPT, a gamma-secretase inhibitor. Primary cultures and genetically modified reporter mice show that increased endocrine cell abundance is due to altered Lgr5+ stem and Neurog3+ endocrine progenitor cell proliferation. Different from the intestine, calorie restriction decreased gastric Lgr5+ stem cells, while increasing a FOXO1/Neurog3+ subpopulation of endocrine progenitors in a Notch-dependent manner. Further, activation of FOXO1 was sufficient to promote endocrine cell differentiation independent of Notch. The Notch inhibitor PF-03084014 or ghrelin receptor antagonist GHRP-6 reversed the phenotypic effects of calorie restriction in mice. Tirzepatide additionally expanded ghrelin+ cells in mice. In summary, calorie restriction promotes Notch-dependent, FOXO1-regulated gastric endocrine cell differentiation.

Study of the antidiabetic mechanism of berberine compound on FOXO1 transcription factor through molecular docking and molecular dynamics simulations.

CONTEXT: Diabetes mellitus (DM) is a metabolic disorder disease that causes hyperglycemia conditions and associated with various chronic complications leading to mortality. Due to high toxicity of conventional diabetic drugs, the exploration of natural compounds as alternative diabetes treatments has been widely carried out. Previous in silico studies have highlighted berberine, a natural compound, as a promising alternative in antidiabetic therapy, potentially acting through various pathways, including the inhibition of the FOXO1 transcription factor in the gluconeogenesis pathway. However, the specific mechanism by which berberine interacts with FOXO1 remains unclear, and research in this area is relatively limited. Therefore, this study aims to determine the stability of berberine structure with FOXO1 based on RMSD, RMSF, binding energy, and trajectory analysis to determine the potential of berberine to inhibit the gluconeogenesis pathway. This research was conducted by in silico method with molecular docking using AutoDock4.2 and molecular dynamics study using Amber20, then visualized by VMD. METHODS: Docking between ligand and FOXO1 receptor was carried out with Autodock4.2. For molecular dynamics simulations, the force fields of DNA.OL15, protein.ff14SB, gaff2, and tip3p were used.

[Notch1/Akt/Foxo1 Pathway Regulated by Kisspeptin Is Involved in Endometrial Decidualization in Patients With Recurrent Spontaneous Abortion]. / kisspeptin调控Notch1/Akt/Foxo1é€šè·¯å‚ä¸Žå¤å‘æ€§æµäº§æ‚£è€ å­å®«å† è†œèœ•è†œåŒ–.

Objective: Kisspeptin, a protein encoded by the KISS1 gene, functions as an essential factor in suppressing tumor growth. The intricate orchestration of cellular processes such as proliferation and differentiation is governed by the Notch1/Akt/Foxo1 signaling pathway, which assumes a central role in maintaining cellular homeostasis. In the specific context of this investigation, the focal point lies in a meticulous exploration of the intricate mechanisms underlying the regulatory effect of kisspeptin on the process of endometrial decidualization. This investigation delves into the interplay between kisspeptin and the Notch1/Akt/Foxo1 signaling pathway, aiming to elucidate its significance in the pathophysiology of recurrent spontaneous abortion (RSA). Methods: We enrolled a cohort comprising 45 individuals diagnosed with RSA, who were admitted to the outpatient clinic of the Reproductive Center at the Second Affiliated Hospital of Soochow University between June 2020 and December 2020. On the other hand, an additional group of 50 women undergoing elective abortion at the outpatient clinic of the Family Planning Department during the same timeframe was also included. To comprehensively assess the molecular landscape, Western blot and RT-qPCR were performed to analyze the expression levels of kisspeptin (and its gene KISS1), IGFBP1 (an established marker of decidualization), Notch1, Akt, and Foxo1 within the decidua. Human endometrial stromal cells (hESC) were given targeted interventions, including treatment with siRNA to disrupt KISS1 or exposure to kisspeptin10 (the bioactive fragment of kisspeptin), and were subsequently designated as the siKP group or the KP10 group, respectively. A control group comprised hESC was transfected with blank siRNA, and cell proliferation was meticulously evaluated with CCK8 assay. Following in vitro induction for decidualization across the three experimental groups, immunofluorescence assay was performed to identify differences in Notch1 expression and decidualization morphology between the siKP and the KP10 groups. Furthermore, RT-qPCR and Western blot were performed to gauge the expression levels of IGFBP1, Notch1, Akt, and Foxo1 across the three cell groups. Subsequently, decidualization was induced in hESC by adding inhibitors targeting Notch1, Akt, and Foxo1. The expression profiles of the aforementioned proteins and genes in the four groups were then examined, with hESC induced for decidualization without adding inhibitors serving as the normal control group. To establish murine models of normal pregnancy (NP) and RSA, CBA/J×BALB/c and CBA/J×DBA/2 mice were used. The mice were respectively labeled as the NP model and RSA model. The experimental groups received intraperitoneal injections of kisspeptin10 and kisspeptin234 (acting as a blocker) and were designated as RSA-KP10 and NP-KP234 groups. On the other hand, the control groups received intraperitoneal injections of normal saline (NS) and were referred to as RSA-NS and NP-NS groups. Each group comprised 6 mice, and uterine tissues from embryos at 9.5 days of gestation were meticulously collected for observation of embryo absorption and examination of the expression of the aforementioned proteins and genes. Results: The analysis revealed that the expression levels of kisspeptin, IGFBP1, Notch1, Akt, and Foxo1 were significantly lower in patients diagnosed with RSA compared to those in women with NP (P<0.01 for kisspeptin and P<0.05 for IGFBP1, Notch1, Akt, and Foxo1). After the introduction of kisspeptin10 to hESC, there was an observed enhancement in decidualization capability. Subsequently, the expression levels of Notch1, Akt, and Foxo1 showed an increase, but they decreased after interference with KISS1. Through immunofluorescence analysis, it was observed that proliferative hESC displayed a slender morphology, but they transitioned to a rounder and larger morphology post-decidualization. Concurrently, the expression of Notch1 increased, suggesting enhanced decidualization upon the administration of kisspeptin10, but the expression decreased after interference with KISS1. Further experimentation involved treating hESC with inhibitors specific to Notch1, Akt, and Foxo1 separately, revealing a regulatory sequence of Notch1/Akt/Foxo1 (P<0.05). In comparison to the NS group, NP mice administered with kisspeptin234 exhibited increased fetal absorption rates (P<0.001) and decreased expression of IGFBP1, Notch1, Akt, and Foxo1 (P<0.05). Conversely, RSA mice administered with kisspeptin10 demonstrated decreased fetal absorption rates (P<0.001) and increased expression levels of the aforementioned molecules (P<0.05). Conclusion: It is suggested that kisspeptin might exert its regulatory influence on the process of decidualization through the modulation of the Notch1/Akt/Foxo1 signaling cascade. A down-regulation of the expression levels of kisspeptin could result in suboptimal decidualization, which in turn might contribute to the development or progression of RSA.

miR-486-5p predicted adverse outcomes of SCAP and regulated K. pneumonia infection via FOXO1.

PURPOSE: Severe community-acquired pneumonia (SCAP) is a common respiratory system disease with rapid development and high mortality. Exploring effective biomarkers for early detection and development prediction of SCAP is of urgent need. The function of miR-486-5p in SCAP diagnosis and prognosis was evaluated to identify a promising biomarker for SCAP. PATIENTS AND METHODS: The serum miR-486-5p in 83 patients with SCAP, 52 healthy individuals, and 68 patients with mild CAP (MCAP) patients were analyzed by PCR. ROC analysis estimated miR-486-5p in screening SCAP, and the Kaplan-Meier and Cox regression analyses evaluated the predictive value of miR-486-5p. The risk factors for MCAP patients developing SCAP were assessed by logistic analysis. The alveolar epithelial cell was treated with Klebsiella pneumonia to mimic the occurrence of SCAP. The targeting mechanism underlying miR-486-5p was evaluated by luciferase reporter assay. RESULTS: Upregulated serum miR-486-5p screened SCAP from healthy individuals and MCAP patients with high sensitivity and specificity. Increasing serum miR-486-5p predicted the poor outcomes of SCAP and served as a risk factor for MCAP developing into SCAP. K. pneumonia induced suppressed proliferation, significant inflammation and oxidative stress in alveolar epithelial cells, and silencing miR-486-5p attenuated it. miR-486-5p negatively regulated FOXO1, and the knockdown of FOXO1 reversed the effect of miR-486-5p in K. pneumonia-treated alveolar epithelial cells. CONCLUSION: miR-486-5p acted as a biomarker for the screening and monitoring of SCAP and predicting the malignancy of MCAP. Silencing miR-486-5p alleviated inflammation and oxidative stress induced by K. pneumonia via negatively modulating FOXO1.

CAPN2 promotes apalutamide resistance in metastatic hormone-sensitive prostate cancer by activating protective autophagy.

Apalutamide, a novel endocrine therapy agent, has been shown to significantly improve the prognosis of patients with metastatic hormone-sensitive prostate cancer (mHSPC). However, resistance to apalutamide has also been reported, and the underlying mechanism for this response has yet to be clearly elucidated. First, this study established apalutamide-resistant prostate cancer (PCa) cells, and confirmed that apalutamide activated the release of calcium ions (Ca2+) and endoplasmic reticulum stress (ERS) to enhance autophagy. Second, RNA sequencing, western blotting, and immunohistochemistry revealed significantly decreased Calpain 2 (CAPN2) expression in the apalutamide-resistant PCa cells and tissues. Furthermore, immunofluorescence and transmission electron microscopy (TEM) showed that CAPN2 promoted apalutamide resistance by activating protective autophagy. CAPN2 promoted autophagy by reducing Forkhead Box O1 (FOXO1) degradation while increasing nuclear translocation via nucleoplasmic protein isolation and immunofluorescence. In addition, FOXO1 promoted protective autophagy through the transcriptional regulation of autophagy-related gene 5 (ATG5). Furthermore, a dual-fluorescence assay confirmed that transcription factor 3 (ATF3) stimulation promoted CAPN2-mediated autophagy activation via transcriptional regulation. In summary, CAPN2 activated protective autophagy by inhibiting FOXO1 degradation and promoting its nuclear translocation via transcriptional ATG5 regulation. ATF3 activation and transcriptional CAPN2 regulation jointly promoted this bioeffect. Thus, our findings have not only revealed the mechanism underlying apalutamide resistance, but also provided a promising new target for the treatment of metastatic PCa.

Exogenous Nucleotides Ameliorate Insulin Resistance Induced by Palmitic Acid in HepG2 Cells through the IRS-1/AKT/FOXO1 Pathways.

Nucleotides (NTs) act as pivotal regulatory factors in numerous biological processes, playing indispensable roles in growth, development, and metabolism across organisms. This study delves into the effects of exogenous NTs on hepatic insulin resistance using palmitic-acid-induced HepG2 cells, administering interventions at three distinct dosage levels of exogenous NTs. The findings underscore that exogenous NT intervention augments glucose consumption in HepG2 cells, modulates the expression of glycogen-synthesis-related enzymes (glycogen synthase kinase 3ß and glycogen synthase), and influences glycogen content. Additionally, it governs the expression levels of hepatic enzymes (hexokinase, phosphoenolpyruvate carboxykinase, and glucose-6-phosphatase). Moreover, exogenous NT intervention orchestrates insulin signaling pathway (insulin receptor substrate-1, protein kinase B, and forkhead box protein O1) and AMP-activated protein kinase (AMPK) activity in HepG2 cells. Furthermore, exogenous NT intervention fine-tunes the expression levels of oxidative stress-related markers (malondialdehyde, glutathione peroxidase, and NADPH oxidase 4) and the expression of inflammation-related nuclear transcription factor (NF-κB). Lastly, exogenous NT intervention regulates the expression levels of glucose transporter proteins (GLUTs). Consequently, exogenous NTs ameliorate insulin resistance in HepG2 cells by modulating the IRS-1/AKT/FOXO1 pathways and regulate glucose consumption, glycogen content, insulin signaling pathways, AMPK activity, oxidative stress, and inflammatory status.

CTLA-4-expressing ILC3s restrain interleukin-23-mediated inflammation.

Interleukin (IL-)23 is a major mediator and therapeutic target in chronic inflammatory diseases that also elicits tissue protection in the intestine at homeostasis or following acute infection1-4. However, the mechanisms that shape these beneficial versus pathological outcomes remain poorly understood. To address this gap in knowledge, we performed single-cell RNA sequencing on all IL-23 receptor-expressing cells in the intestine and their acute response to IL-23, revealing a dominance of T cells and group 3 innate lymphoid cells (ILC3s). Unexpectedly, we identified potent upregulation of the immunoregulatory checkpoint molecule cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) on ILC3s. This pathway was activated by gut microbes and IL-23 in a FOXO1- and STAT3-dependent manner. Mice lacking CTLA-4 on ILC3s exhibited reduced regulatory T cells, elevated inflammatory T cells and more-severe intestinal inflammation. IL-23 induction of CTLA-4+ ILC3s was necessary and sufficient to reduce co-stimulatory molecules and increase PD-L1 bioavailability on intestinal myeloid cells. Finally, human ILC3s upregulated CTLA-4 in response to IL-23 or gut inflammation and correlated with immunoregulation in inflammatory bowel disease. These results reveal ILC3-intrinsic CTLA-4 as an essential checkpoint that restrains the pathological outcomes of IL-23, suggesting that disruption of these lymphocytes, which occurs in inflammatory bowel disease5-7, contributes to chronic inflammation.

Punicalagin Ameliorates Diabetic Liver Injury by Inhibiting Pyroptosis and Promoting Autophagy via Modulation of the FoxO1/TXNIP Signaling Pathway.

Diabetic liver injury (DLI) is one of the complications of diabetes mellitus, which seriously jeopardizes human health. Punicalagin (PU), a polyphenolic compound mainly found in pomegranate peel, has been shown to ameliorate metabolic diseases such as DLI, and the mechanism needs to be further explored. In this study, a HFD/STZ-induced diabetic mouse model is established to investigate the effect and mechanism of PU on DLI. The results show that PU intervention significantly improves liver histology and serum biochemical abnormalities in diabetic mice, significantly inhibits the expression of pyroptosis-related proteins such as NLRP3, Caspase1, IL-1ß, and GSDMD in the liver of diabetic mice, and up-regulated the expression of autophagy-related proteins. Meanwhile, PU treatment significantly increases FoxO1 protein expression and inhibits TXNIP protein expression in the liver of diabetic mice. The above results are further verified in the HepG2 cell injury model induced by high glucose. AS1842856 is a FoxO1 specific inhibitor. The intervention of AS1842856 combined with PU reverses the regulatory effects of PU on pyroptosis and autophagy in HepG2 cells. In conclusion, this study demonstrates that PU may inhibit pyroptosis and upregulate autophagy by regulating FoxO1/TXNIP signaling, thereby alleviating DLI.

Genetic Insights into Colorectal Cancer: Evaluating PI3K/AKT Signaling Pathway Genes Expression.

The PI3K/AKT pathway plays a pivotal role in cellular processes, and its dysregulation is implicated in various cancers, including colorectal cancer. The present study correlates the expression levels of critical genes (PIK3CA, PTEN, AKT1, FOXO1, and FRAP) in 60 tumor tissues with clinicopathological and demographic characteristics. The results indicate age-related variation in FOXO1 gene expression, with higher levels observed in patients aged 68 and above. In addition, tumors originating from the rectum exhibit higher FOXO1 expression compared to colon tumors, suggesting region-specific differences in expression. The results also identify the potential correlation between PTEN, PIK3CA gene expression, and parameters such as tumor grade and neuroinvasion. The bioinformatic comparative analysis found that PTEN and FOXO1 expressions were downregulated in colorectal cancer tissue compared to normal colon tissue. Relapse-free survival analysis based on gene expression identified significant correlations, highlighting PTEN and FRAP as potential indicators of favorable outcomes. Our findings provide a deeper understanding of the role of the PI3K/AKT pathway in colorectal cancer and the importance of understanding the molecular basis of colorectal cancer development and progression.

P53 Activation Promotes Maturational Characteristics of Pluripotent Stem Cell-Derived Cardiomyocytes in 3-Dimensional Suspension Culture Via FOXO-FOXM1 Regulation.

BACKGROUND: Current protocols generate highly pure human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) in vitro that recapitulate characteristics of mature in vivo cardiomyocytes. Yet, a risk of arrhythmias exists when hiPSC-CMs are injected into large animal models. Thus, understanding hiPSC-CM maturational mechanisms is crucial for clinical translation. Forkhead box (FOX) transcription factors regulate postnatal cardiomyocyte maturation through a balance between FOXO and FOXM1. We also previously demonstrated that p53 activation enhances hiPSC-CM maturation. Here, we investigate whether p53 activation modulates the FOXO/FOXM1 balance to promote hiPSC-CM maturation in 3-dimensional suspension culture. METHODS AND RESULTS: Three-dimensional cultures of hiPSC-CMs were treated with Nutlin-3a (p53 activator, 10 µM), LOM612 (FOXO relocator, 5 µM), AS1842856 (FOXO inhibitor, 1 µM), or RCM-1 (FOXM1 inhibitor, 1 µM), starting 2 days after onset of beating, with dimethyl sulfoxide (0.2% vehicle) as control. P53 activation promoted hiPSC-CM metabolic and electrophysiological maturation alongside FOXO upregulation and FOXM1 downregulation, in n=3 to 6 per group for all assays. FOXO inhibition significantly decreased expression of cardiac-specific markers such as TNNT2. In contrast, FOXO activation or FOXM1 inhibition promoted maturational characteristics such as increased contractility, oxygen consumption, and voltage peak maximum upstroke velocity, in n=3 to 6 per group for all assays. Further, by single-cell RNA sequencing of n=2 LOM612-treated cells compared with dimethyl sulfoxide, LOM612-mediated FOXO activation promoted expression of cardiac maturational pathways. CONCLUSIONS: We show that p53 activation promotes FOXO and suppresses FOXM1 during 3-dimensional hiPSC-CM maturation. These results expand our understanding of hiPSC-CM maturational mechanisms in a clinically-relevant 3-dimensional culture system.

M6A demethylase FTO-stabilized exosomal circBRCA1 alleviates oxidative stress-induced granulosa cell damage via the miR-642a-5p/FOXO1 axis.

BACKGROUND: Premature ovarian insufficiency (POI) is an important cause of female infertility and seriously impacts the physical and psychological health of patients. Human umbilical cord mesenchymal stem cell-derived exosomes (HucMSCs-Exs, H-Exs) have exhibited protective effects on ovarian function with unclear mechanisms. METHODS: A comprehensive analysis of the Gene Expression Omnibus (GEO) database were used to identify POI-associated circRNAs and miRNAs. The relationship between HucMSC-derived exosomal circBRCA1/miR-642a-5p/FOXO1 axis and POI was examined by RT-qPCR, Western blotting, reactive oxygen species (ROS) staining, senescence-associated ß-gal (SA-ß-gal) staining, JC-1 staining, TEM, oxygen consumption rate (OCR) measurements and ATP assay in vivo and in vitro. RT-qPCR detected the expression of circBRCA1 in GCs and serum of patients with normal ovarian reserve function (n = 50) and patients with POI (n = 50); then, the correlation of circBRCA1 with ovarian reserve function indexes was analyzed. RESULTS: Herein, we found that circBRCA1 was decreased in the serum and ovarian granulosa cells (GCs) of patients with POI and was associated with decreased ovarian reserve. H-Exs improved the disorder of the estrous cycles and reproductive hormone levels, reduced the number of atretic follicles, and alleviated the apoptosis and senescence of GCs in rats with POI. Moreover, H-Exs mitigated mitochondrial damage and reversed the reduced circBRCA1 expression induced by oxidative stress in GCs. Mechanistically, FTO served as an eraser to increase the stability and expression of circBRCA1 by mediating the m6A demethylation of circBRCA1, and exosomal circBRCA1 sponged miR-642a-5p to block its interaction with FOXO1. CircBRCA1 insufficiency aggravated mitochondrial dysfunction, mimicking FTO or FOXO1 depletion effects, which was counteracted by miR-642a-5p inhibition. CONCLUSION: H-Exs secreted circBRCA1 regulated by m6A modification, directly sponged miR-642a-5p to upregulate FOXO1, resisted oxidative stress injuries in GCs and protected ovarian function in rats with POI. Exosomal circBRCA1 supplementation may be a general prospect for the prevention and treatment of POI.

Palmitic acid reduces the methylation of the FOXO1 promoter to suppress the development of diffuse large B-cell lymphoma via modulating the miR-429/DNMT3A axis.

Diffuse large B-cell lymphoma (DLBCL) is characterized by significant treatment resistance. Palmitic acid (PA) has shown promising antitumor properties. This study aims to elucidate the molecular mechanisms by which PA influences DLBCL progression. We quantified the expression levels of microRNAs (miRNAs), Forkhead box protein O1 (FOXO1), and DNA methyltransferase 3A (DNMT3A) in both untreated and PA-treated DLBCL tumors and cell lines. Assessments were made of cell viability, apoptosis, and autophagy-related protein expression following PA administration. Interaction analyses among miR-429, DNMT3A, and FOXO1 were conducted using luciferase reporter assays and methylation-specific (MSP) Polymerase chain reaction (PCR). After transfecting the miR-429 inhibitor, negative control (NC) inhibitor, shRNA against DNMT3A (sh-DNMT3A), shRNA negative control (sh-NC), overexpression vector for DNMT3A (oe-DNMT3A), or overexpression negative control (oe-NC), we evaluated the effects of miR-429 and DNMT3A on cell viability, mortality, and autophagy-related protein expression in PA-treated DLBCL cell lines. The efficacy of PA was also tested in vivo using DLBCL tumor-bearing mouse models. MiR-429 and FOXO1 expression levels were downregulated, whereas DNMT3A was upregulated in DLBCL compared to the control group. PA treatment was associated with enhanced autophagy, mediated by the upregulation of miR-429 and downregulation of DNMT3A. The luciferase reporter assay and MSP confirmed that miR-429 directly inhibits DNMT3A, thereby reducing FOXO1 methylation. Subsequent experiments demonstrated that PA promotes autophagy and inhibits DLBCL progression by upregulating miR-429 and modulating the DNMT3A/FOXO1 axis. In vivo PA significantly reduced the growth of xenografted tumors through its regulatory impact on the miR-429/DNMT3A/FOXO1 axis. Palmitic acid may modulate autophagy and inhibit DLBCL progression by targeting the miR-429/DNMT3A/FOXO1 signaling pathway, suggesting a novel therapeutic target for DLBCL management.

The Long Non-Coding RNA Gene AC027288.3 Plays a Role in Human Endometrial Stromal Fibroblast Decidualization.

During the secretory phase of the menstrual cycle, endometrial fibroblast cells begin to change into large epithelial-like cells called decidual cells in a process called decidualization. This differentiation continues more broadly in the endometrium and forms the decidual tissue during early pregnancy. The cells undergoing decidualization as well as the resulting decidual cells, support successful implantation and placentation during early pregnancy. This study was carried out to identify new potentially important long non-coding RNA (lncRNA) genes that may play a role in human endometrial stromal fibroblast cells (hESF) undergoing decidualization in vitro, and several were found. The expression of nine was further characterized. One of these, AC027288.3, showed a dramatic increase in the expression of hESF cells undergoing decidualization. When AC027288.3 expression was targeted, the ability of the cells to undergo decidualization as determined by the expression of decidualization marker protein-coding genes was significantly altered. The most affected markers of decidualization whose expression was significantly reduced were FOXO1, FZD4, and INHBA. Therefore, AC027288.3 may be a major upstream regulator of the WNT-FOXO1 pathway and activin-SMAD3 pathways previously shown as critical for hESF decidualization. Finally, we explored possible regulators of AC027288.3 expression during human ESF decidualization. Expression was regulated by cAMP and progesterone. Our results suggest that AC027288.3 plays a role in hESF decidualization and identifies several other lncRNA genes that may also play a role.

Upregulation of the AMPK-FOXO1-PDK4 pathway is a primary mechanism of pyruvate dehydrogenase activity reduction in tafazzin-deficient cells.

Barth syndrome (BTHS) is a rare disorder caused by mutations in the TAFAZZIN gene. Previous studies from both patients and model systems have established metabolic dysregulation as a core component of BTHS pathology. In particular, features such as lactic acidosis, pyruvate dehydrogenase (PDH) deficiency, and aberrant fatty acid and glucose oxidation have been identified. However, the lack of a mechanistic understanding of what causes these conditions in the context of BTHS remains a significant knowledge gap, and this has hindered the development of effective therapeutic strategies for treating the associated metabolic problems. In the current study, we utilized tafazzin-knockout C2C12 mouse myoblasts (TAZ-KO) and cardiac and skeletal muscle tissue from tafazzin-knockout mice to identify an upstream mechanism underlying impaired PDH activity in BTHS. This mechanism centers around robust upregulation of pyruvate dehydrogenase kinase 4 (PDK4), resulting from hyperactivation of AMP-activated protein kinase (AMPK) and subsequent transcriptional upregulation by forkhead box protein O1 (FOXO1). Upregulation of PDK4 in tafazzin-deficient cells causes direct phospho-inhibition of PDH activity accompanied by increased glucose uptake and elevated intracellular glucose concentration. Collectively, our findings provide a novel mechanistic framework whereby impaired tafazzin function ultimately results in robust PDK4 upregulation, leading to impaired PDH activity and likely linked to dysregulated metabolic substrate utilization. This mechanism may underlie previously reported findings of BTHS-associated metabolic dysregulation.