FoxO Transcription Factors Research Articles

PARP12-mediated ADP-ribosylation contributes to breast cancer cell fate by regulating AKT activation and DNA-damage response

Breast cancer represents the primary cause of death of women under 65 in developed countries, due to the acquisition of multiple drug resistance mechanisms. The PI3K/AKT pathway is one of the major regulating mechanisms altered during the development of endocrine resistance and inhibition of steps in this signalling pathway are adopted as a key strategy to overcome this issue. ADP-ribosylation is a post-translational modification catalysed by PARP enzymes that regulates essential cellular processes, often altered in diseases. PARP12, a member of this family, has been associated with the onset of drug resistance in oestrogen receptor-positive breast cancers, making this enzyme a promising drug target. The molecular basis underlying its involvement in the acquisition of resistance are unknown to date. Here, we demonstrate that PARP12-mediated mono-ADP-ribosylation of AKT is required for AKT activation whilst the absence of PARP12 leads to apoptosis induction in a subset of oestrogen receptor-positive breast cancer cells. Our data show that transcriptional inhibition of PARP12 correlates with an increased DNA-damage induction, mirrored by augmented p53 nuclear localisation and enhanced p53-AKT interaction. Under these conditions, AKT is functionally incompetent towards its downstream targets FOXO, hence favouring cell death. This is achieved by increasing protein levels of the FOXO1 transcription factor, that in turn activates the apoptotic cascade. Overall, we show a novel regulation step of AKT activation and apoptosis relying on PARP12-mediated mono-ADP-ribosylation and propose PARP12 as a potential pharmacological target to be exploited as an innovative therapeutical strategy to overcome endocrine resistance.

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

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

The multifaceted function of FoxO1 in pancreatic β-cell dysfunction and insulin resistance: Therapeutic potential for type 2 diabetes.

The forkhead box O1 (FOXO1), the first discovered member of the FoxO family, is a critical transcription factor predominantly found in insulin-secreting and insulin-sensitive tissues. In the pancreas of adults, FoxO1 expression is restricted to islet β cells. We determined that in human islet microarray datasets, FoxO1 expression is higher than other FoxO transcription factors. Our analyses of three human islet datasets revealed that FoxO1 expression tends to shows a negative correlation with type 2 diabetes and no correlation with body mass index (BMI) between individuals with low levels of HbA1C (or ND, non-diabetic) and high levels of HbA1C (or T2D, type 2 diabetes). However, FoxO1 function is multifaceted and mainly regulated by post-translational modifications including phosphorylation and deacetylation that involved in pancreatic β cell function and insulin sensitivity. This study summarized the molecular mechanisms underlying the role of FoxO1 activity in pancreatic β-cell dysfunction and insulin resistance in T2D. In addition, we discussed the therapeutic potential of FoxO1 inhibitors in diabetes treatment.

Unraveling the AMPK-SIRT1-FOXO Pathway: The In-Depth Analysis and Breakthrough Prospects of Oxidative Stress-Induced Diseases.

Oxidative stress (OS) refers to the production of a substantial amount of reactive oxygen species (ROS), leading to cellular and organ damage. This imbalance between oxidant and antioxidant activity contributes to various diseases, including cancer, cardiovascular disease, diabetes, and neurodegenerative conditions. The body's antioxidant system, mediated by various signaling pathways, includes the AMPK-SIRT1-FOXO pathway. In oxidative stress conditions, AMPK, an energy sensor, activates SIRT1, which in turn stimulates the FOXO transcription factor. This cascade enhances mitochondrial function, reduces mitochondrial damage, and mitigates OS-induced cellular injury. This review provides a comprehensive analysis of the biological roles, regulatory mechanisms, and functions of the AMPK-SIRT1-FOXO pathway in diseases influenced by OS, offering new insights and methods for understanding OS pathogenesis and its therapeutic approaches.

Bacterial purine metabolism modulates C. elegans development and stress tolerance via DAF-16.

The purine metabolism is crucial for cellular function and is a conserved metabolic network from prokaryotes to humans. While extensively studied in microorganisms like yeast and bacteria, the impact of perturbing dietary intermediates from the purine biosynthesis on animal development and growth remains poorly understood. We utilized Caenorhabditis elegans as the metazoan model to investigate the mechanisms underlying this deficiency. Through a high-throughput screening of an Escherichia coli mutant library Keio collection, we identified 34 E. coli mutants that delay C. elegans development. Among these mutants, we found that E. coli purE gene is an essential genetic component that promotes host development in a dose-dependent manner. Further metabolites supplementation suggests that bacterial purE downstream metabolite 5-aminoimidazole-4-carboxamide ribotide (AICAR) can inhibit worm growth. Additionally, we found the FoxO transcription factor DAF-16 is indispensable in worm development delay induced by purE mutation, and observed increased nuclear accumulation of DAF-16 when fed E. coli purE- mutants, suggesting the role of DAF-16 in response to purE mutation. RNA-seq analysis and phenotypic assays revealed that worms fed the E. coli purE mutant exhibited elevated lifespan, thermotolerance, and pathogen resistance. These findings collectively suggest that certain intermediates in the bacterial purine biosynthesis can serve as a cue to modulate development and activate the defense response in the nematode C. elegans through DAF-16.

SGLT2 inhibitor downregulates ANGPTL4 to mitigate pathological aging of cardiomyocytes induced by type 2 diabetes

BackgroundSenescence is recognized as a principal risk factor for cardiovascular diseases, with a significant association between the senescence of cardiomyocytes and inferior cardiac function. Furthermore, type 2 diabetes exacerbates this aging process. Sodium-glucose co-transporter 2 inhibitor (SGLT2i) has well-established cardiovascular benefits and, in recent years, has been posited to possess anti-aging properties. However, there are no reported data on their improvement of cardiomyocytes function through the alleviation of aging. Consequently, our study aims to investigate the mechanism by which SGLT2i exerts anti-aging and protective effects at the cardiac level through its action on the FOXO1-ANGPTL4 pathway.MethodsTo elucidate the underlying functions and mechanisms, we established both in vivo and in vitro disease models, utilizing mice with diabetic cardiomyopathy (DCM) induced by type 2 diabetes mellitus (T2DM) through high-fat diet combined with streptozotocin (STZ) administration, and AC16 human cardiomyocyte cell subjected to stimulation with high glucose (HG) and palmitic acid (PA). These models were employed to assess the changes in the senescence phenotype of cardiomyocytes and cardiac function following treatment with SGLT2i. Concurrently, we identified ANGPTL4, a key factor contributing to senescence in DCM, using RNA sequencing (RNA-seq) technology and bioinformatics methods. We further clarified ANGPTL4 role in promoting pathological aging of cardiomyocytes induced by hyperglycemia and hyperlipidemia through knockdown and overexpression of the factor, as well as analyzed the impact of SGLT2i intervention on ANGPTL4 expression. Additionally, we utilized chromatin immunoprecipitation followed by quantitative real-time PCR (ChIP-qPCR) to confirm that FOXO1 is essential for the transcriptional activation of ANGPTL4.ResultsThe therapeutic intervention with SGLT2i alleviated the senescence phenotype in cardiomyocytes of the DCM mouse model constructed by high-fat feeding combined with STZ, as well as in the AC16 model stimulated by HG and PA, while also improving cardiac function in DCM mice. We observed that the knockdown of ANGPTL4, a key senescence-promoting factor in DCM identified through RNA-seq technology and bioinformatics, mitigated the senescence of cardiomyocytes, whereas overexpression of ANGPTL4 exacerbated it. Moreover, SGLT2i improved the senescence phenotype by suppressing the overexpression of ANGPTL4. In fact, we discovered that SGLT2i exert their effects by regulating the upstream transcription factor FOXO1 of ANGPTL4. Under conditions of hyperglycemia and hyperlipidemia, compared to the control group without FOXO1, the overexpression of FOXO1 in conjunction with SGLT2i intervention significantly reduced both ANGPTL4 mRNA and protein levels. This suggests that the FOXO1-ANGPTL4 axis may be a potential target for the cardioprotective effects of SGLT2i.ConclusionsCollectively, our study demonstrates that SGLT2i ameliorate the pathological aging of cardiomyocytes induced by a high glucose and high fat metabolic milieu by regulating the interaction between FOXO1 and ANGPTL4, thereby suppressing the transcriptional synthesis of the latter, and consequently restoring cardiac function.Graphical abstract

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.

DEAD-box RNA helicase DDX-23 mediates dietary restriction induced health span in Caenorhabditis elegans.

Dietary restriction (DR) extends lifespan in diverse species, from yeast to mammals. However, its underlying mechanisms are not well understood. In this study, through using the tractable model Caenorhabditis elegans, we show a role for the DEAD-box RNA helicase, DDX-23 (homologous to mammal DDX23) as a regulator of healthspan in response to dietary restriction. Meanwhile, DDX-23 is also required for heat and oxidative stress response in C. elegans. Intriguingly, DDX-23 functions in the germline during adult to regulate dietary restriction-induced longevity. We then find that PHA-4/FOXA acts downstream of DDX-23 to mediate the transcriptional response of SOD-related genes and consequently the lifespan of the animals. Furthermore, we find that the DEAD-box RNA helicase, DDX-23 negatively regulates the healthy lifespan extension by up-regulating the expression of miR-231, and resulting in suppressing the activation of FOXO transcription factor DAF-16. Our work shows a newly discovered for DEAD-box RNA helicase DDX-23 in the regulation of dietary restriction-mediated longevity in C. elegans and reveals the downstream transcriptional regulation mechanisms.

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.

Measuring FOXO Activity by Using qPCR-Based Expression Analysis of FOXO Target Genes.

FOXO transcription factors belong to the forkhead protein family and are distinguished by their unique forkhead (FKH) DNA-binding domain. In the realm of mammals, four FOXO paralogs are recognized: FOXO1, FOXO3, FOXO4, and FOXO6. These paralogs are evolutionary counterparts of the daf-16 gene discovered in the nematode C. elegans. A key feature shared by these paralogs is a consensus binding site known as the DAF-16 family protein-binding site (DBE: 5'-TTGTTTAC-3'). The functional outcome of FOXO transcription factors primarily hinges on their affinity for these specific binding sites within the promoters of their target genes. Nevertheless, it is worth noting that many of these target genes exhibit tissue-specific expression patterns. Consequently, there is not a single FOXO target gene whose expression can reliably serve as a universal indicator of FOXO activity across all cell types and tissues or in response to all stimuli. In light of these considerations, we present a collection of target genes that, when collectively assessed, can accurately gauge FOXO activation. In this chapter, we outline a specific protocol for utilizing quantitative reverse transcription polymerase chain reaction (qRT-PCR) to measure the expression levels of these genes.

Characterizing the Role of daf-16/C. elegans FOXO in Lifespan and Healthspan.

In Caenorhabditis elegans (C. elegans), there is a single FOXO transcription factor homolog, encoded by the gene, daf-16. As a central regulator for multiple pathways, DAF-16 integrates these signals to result in changes in longevity, development, fat storage, stress resistance, innate immunity, and reproduction. One of the main advantages of using C. elegans is the ability to study FOXO in the context of the whole animal. Therefore, manipulating the levels or the activity of daf-16 results in visible, scorable phenotypic changes. DAF-16 is the downstream target of the conserved insulin/IGF-1 signaling (IIS) pathway, a PI 3-kinase signaling cascade that ultimately controls its nuclear localization. Since the IIS pathway is a major regulator of lifespan, almost all studies of lifespan modulation examine the requirement of daf-16. More recently, lifespan analysis has been accompanied by healthspan analysis, referring to the time an animal is healthy. In this chapter, I will focus on the assays to assess lifespan and healthspan of C. elegans FOXO/daf-16, in the context of a whole animal.

Phosphorylation of FOXO Proteins as a Key Mechanism to Regulate Their Activity.

Phosphorylation of FOXO transcription factors is one of the key mechanisms involved in the regulation of the activity, nucleo-cytosolic shuttling, and stability of this family of proteins. Here we describe several experimental approaches allowing analysis of changes in the phosphorylation of these proteins upon exposure to different stimuli.

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.

The Activity of Trisindoline 5 Compound againsts c-Myc and FoxO1, 3, 4 Gene Expression on MDA-MB-231 Breast Cancer Stem Cells

Unoptimum curing and controlling proliferation of cancer cells in breast is due to the presence of BCSCs (Breast cancer stem cells), which are associated with stemness, self-renewal, tumour initiation and metastasis. Similarly, overexpression of c-Myc (oncogenic transcription factor) in breast cancer has become potential as target of cancer therapy. Inhibition of c-Myc in cancer cells can increase the transcription factors FoxO family members including FoxO1, 3, 4 and their target genes involved in apoptosis, cell cycle arrest and autophagy. Trisindoline is an indole timer alkaloid natural compound, which is toxic to cancer cells. For this reason, we aim to decide the activity of one of derivate compound of trisindoline, namely as trisindoline 5 on BCSCs MDA-MB-231 through cytotoxicity, apoptosis, and gene expression of c-Myc and FoxO1, 3, 4. As a result, MTT assay showed trisindoline 5 can decrease the viability of BCSCs MDA-MB-231 with IC50 13.127µg/ml. Furthermore, flow cytometry analysis shown that trisindoline 5 can induce apoptosis 5.23% at concentration of 25µg/ml. Similarly, qPCR analysis showed the highest decrease in c-Myc was found in trisindoline 5 concentration of 25µg/ml with 0.0746-fold. Meanwhile, the highest increase FoxO1, 3, 4 expression was found in trisindoline 5 concentration of 25µg/ml, 20.6452-fold, 26.4709-fold, and 12.8341-fold respectively. Therefore, we conclude that trisindoline 5 concentration of 25µg/ml was able to decrease the expression of c-Myc and increase the expression of FoxO1, 3, 4 despites, it was not effective enough in reducing the population of BCSCs MDA-MB-231.

Acupuncture and cellular mechanisms: the role of foxo transcription factors in autophagy and senescence.

The current narrative review was planned to elucidate the interplay between acupuncture, a cornerstone of Traditional Chinese Medicine, and the modulation of cellular mechanisms via Forkhead box O transcription factors, focussing on autophagy and cellular senescence. Autophagy, essential for cellular health, and cellular senescence, associated with aging and age-related diseases, are both significantly influenced by Forkhead box O transcription factors among other regulatory factors and pathways. These factors, known to diminish with age, play a pivotal role in promoting longevity. The current review analysed experimental models demonstrating acupuncture's capacity to activate Forkhead box O transcription factors, thereby inducing autophagy and reducing cellular senescence. Evidence from studies on human fibroblasts, ageing animal models, obesity-induced insulin resistance, and osteoporosis corroborates the beneficial effects of acupuncture. Despite these promising findings, the complexities of Forkhead box O transcription factors' activation by acupuncture and their precise impact on cellular processes warrant further investigation with a particular focus on the distinct roles of Forkhead box O isoforms.

A non-canonical role of somatic Cyclin D/CYD-1 in oogenesis and in maintenance of reproductive fidelity, dependent on the FOXO/DAF-16 activation state.

For the optimal survival of a species, an organism coordinates its reproductive decisions with the nutrient availability of its niche. Thus, nutrient-sensing pathways like insulin-IGF-1 signaling (IIS) play an important role in modulating cell division, oogenesis, and reproductive aging. Lowering of the IIS leads to the activation of the downstream FOXO transcription factor (TF) DAF-16 in Caenorhabditis elegans which promotes oocyte quality and delays reproductive aging. However, less is known about how the IIS axis responds to changes in cell cycle proteins, particularly in the somatic tissues. Here, we show a new aspect of the regulation of the germline by this nutrient-sensing axis. First, we show that the canonical G1-S cyclin, Cyclin D/CYD-1, regulates reproductive fidelity from the uterine tissue of wild-type worms. Then, we show that knocking down cyd-1 in the uterine tissue of an IIS receptor mutant arrests oogenesis at the pachytene stage of meiosis-1 in a DAF-16-dependent manner. We observe activated DAF-16-dependent deterioration of the somatic gonadal tissues like the sheath cells, and transcriptional de-regulation of the sperm-to-oocyte switch genes which may be the underlying reason for the absence of oogenesis. Deleting DAF-16 releases the arrest and leads to restoration of the somatic gonad but poor-quality oocytes are produced. Together, our study reveals the unrecognized cell non-autonomous interaction of Cyclin D/CYD-1 and FOXO/DAF-16 in the regulation of oogenesis and reproductive fidelity.

Erucin, a Natural Isothiocyanate, Prevents Polyglutamine-Induced Toxicity in Caenorhabditis elegans via aak-2/AMPK and daf-16/FOXO Signaling.

Several neurodegenerative diseases (NDDs), such as Huntington's disease, six of the spinocerebellar ataxias, dentatorubral-pallidoluysian atrophy, and spinobulbar muscular atrophy, are caused by abnormally long polyglutamine (polyQ) tracts. Natural compounds capable of alleviating polyQ-induced toxicity are currently of great interest. In this work, we investigated the modulatory effect against polyQ neurotoxic aggregates exerted by erucin (ERN), an isothiocyanate naturally present in its precursor glucoerucin in rocket salad leaves and in its oxidized form, sulforaphane (SFN), in broccoli. Using C. elegans models expressing polyQ in different tissues, we demonstrated that ERN protects against polyQ-induced toxicity and that its action depends on the catalytic subunit of AMP-activated protein kinase (aak-2/AMPKα2) and, downstream in this pathway, on the daf-16/FOXO transcription factor, since nematodes deficient in aak-2/AMPKα2 and daf-16 did not respond to the treatment, respectively. Although triggered by a different source of neurotoxicity than polyQ diseases, i.e., by α-synuclein (α-syn) aggregates, Parkinson's disease (PD) was also considered in our study. Our results showed that ERN reduces α-syn aggregates and slightly improves the motility of worms. Therefore, further preclinical studies in mouse models of protein aggregation are justified and could provide insights into testing whether ERN could be a potential neuroprotective compound in humans.

FoxO1 signaling in B cell malignancies and its therapeutic targeting.

FoxO transcription factors (FoxO1, FoxO3a, FoxO4, FoxO6) are a highly evolutionary conserved subfamily of the 'forkhead' box proteins. They have traditionally been considered tumor suppressors, but FoxO1 also exhibits oncogenic properties. The complex nature of FoxO1 is illustrated by its various roles in B cell development and differentiation, immunoglobulin gene rearrangement and cell-surface B cell receptor (BCR) structure, DNA damage control, cell cycle regulation, and germinal center reaction. FoxO1 is tightly regulated at a transcriptional (STAT3, HEB, EBF, FoxOs) and post-transcriptional level (Akt, AMPK, CDK2, GSK3, IKKs, JNK, MAPK/Erk, SGK1, miRNA). In B cell malignancies, recurrent FoxO1 activating mutations (S22/T24) and aberrant nuclear export and activity have been described, underscoring the potential of its therapeutic inhibition. Here, we review FoxO1's roles across B cell and myeloid malignancies, namely acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), chronic lymphocytic leukemia (CLL), follicular lymphoma (FL), diffuse large B cell lymphoma (DLBCL), mantle cell lymphoma (MCL), Burkitt lymphoma (BL), Hodgkin lymphoma (HL), and multiple myeloma (MM). We also discuss preclinical evidence for FoxO1 targeting by currently available inhibitors (AS1708727, AS1842856, cpd10).

Genistein Induces Ferroptosis in Colorectal Cancer Cells via FoxO3/SLC7A11/GPX4 Signaling Pathway.

Colorectal cancer is among the most frequently diagnosed cancers with high mortality rates and poses a serious threat to human health. Genistein (Gen) has been found to have anti-colorectal cancer effects, however, the molecular mechanisms by which genistein elicits its effects on colorectal cancer (CRC) cells have not been fully elucidated. In this study, we investigated the oxidative state of colorectal cancer cells during the antitumor action of Genistein and whether it can exert its antitumor effects through ferroptosis. Current research on the oxidative state of Genistein indicates that it exhibits both antioxidant and pro-oxidant properties. Different drug concentrations were applied to colorectal cancer cells, after which cell viability and key markers of ferroptosis, including reactive oxygen species (ROS), malondialdehyde (MDA), and Fe2+, were measured. We found that genistein significantly reduced the viability of colorectal cancer cells, and the expression of ferroptosis markers increased in a concentration-dependent manner. Subsequently, we treated cells with the ferroptosis inhibitor fer-1 in combination with genistein and observed a partial reversal of ferroptosis markers. These findings suggest that genistein exerts its antitumor effect by promoting iron-dependent oxidative damage-induced ferroptosis. To further elucidate the mechanism underlying ferroptosis modulation, we examined the protein and mRNA expression levels of the classical key ferroptosis molecules SLC7A11 and GPX4. We found that the expression levels of these molecules decreased, with GPX4 exhibiting a greater decrease. Overexpression of GPX4 reversed the pro-ferroptotic effect of genistein, indicating that genistein promotes ferroptosis occurrence by downregulating GPX4 expression. When the drug was applied to colorectal cancer cells, the expression of the transcription factor FoxO3 increased. Treatment of cells with the FoxO3 inhibitor JY-2 in combination with other drugs resulted in antagonism of ferroptosis markers. These findings suggest that genistein induces ferroptosis in colorectal cancer cells through the FoxO3/SLC7A11/GPX4 signaling pathway, thereby inhibiting tumor growth.

Senolytics Enhance the Longevity of Caenorhabditis elegans by Altering Betaine Metabolism.

Aging triggers physiological changes in organisms that are tightly linked to metabolic changes. Senolytics targeting many fundamental aging processes are currently being developed. However, the host metabolic response to natural senescence and the molecular mechanism underlying the antiaging benefits of senolytics remain poorly understood. In this study, we investigated metabolic changes during natural senescence based on the Caenorhabditis elegans model and pinpointed potential biomarkers linked to the benefits of senolytics. These results suggest that age-dependent metabolic changes during natural aging occur in C elegans. Betaine was identified as a crucial metabolite in the natural aging process. We explored the metabolic effects of aging interventions by administering 3 antiaging drugs-metformin, quercetin, and minocycline-to nematodes. Notably, betaine expression significantly increased under the 3 antiaging drug treatments. Our findings demonstrated that betaine supplementation extends lifespan, primarily through pathways associated with the forkhead box transcription factor (FoxO) signaling pathway, the p38-mitogen-activated protein kinase (MAPK) signaling pathway, autophagy, the longevity regulating pathway, and the target of rapamycin (mTOR) signaling pathway. In addition, autophagy and free radicals are altered in betaine-treated nematodes. Overall, we found that betaine is a critical metabolite during natural aging and that senolytics extend the lifespan of nematodes by increasing betaine levels and promoting autophagy and antioxidant activity. This finding suggests that betaine could be a novel therapeutic target for promoting longevity.