A Review of FoxO1-Regulated Metabolic Diseases and Related Drug Discoveries

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.

Deletion of the foxO1 gene reduces hypoxia tolerance in zebrafish embryos by influencing erythropoiesis

FoxO1 (Forkhead box O1) belongs to the evolutionarily conserved FoxO subfamily and is involved in diverse physiologic processes, including apoptosis, cell cycle, DNA damage repair, oxidative stress and cell differentiation. FoxO1 plays an important role in regulating the hypoxia microenvironment such as cancers, but its role in hypoxia adaptation remains unclear in animals. To understand the function of foxO1 in hypoxia response, we constructed foxO1a and foxO1b mutant zebrafish using CRISPR/Cas9 technology. It was found that foxO1a and foxO1b destruction affected the hematopoietic system in the early zebrafish embryos. Specifically, FoxO1a and FoxO1b were found to affect the transcriptional activity of runx1, a marker gene for hematopoietic stem cells (HSCs). Moreover, foxO1a and foxO1b had complementary features in hypoxia response, and foxO1a or/and foxO1b destruction resulted in tolerance of zebrafish becoming weakened in hypoxia due to insufficient hemoglobin supply. Additionally, the transcriptional activity of these two genes was demonstrated to be regulated by Hif1α. In conclusion, foxO1a and foxO1b respond to Hif1α-mediated hypoxia response by participating in zebrafish erythropoiesis. These results will provide a theoretical basis for further exploring the function of FoxO1 in hematopoiesis and hypoxia response.

Bictegravir alters glucose tolerance in vivo and causes hepatic mitochondrial dysfunction

Growing evidence associates antiretroviral therapies containing integrase strand transfer inhibitors or tenofovir alafenamide (TAF) with increased weight gain and metabolic diseases, but the underlying mechanisms remain unclear. This study evaluated the impact of lamivudine, dolutegravir (DTG), bictegravir (BIC), tenofovir disoproxil fumarate, and TAF on metabolic alterations, and explored glucose homeostasis and mitochondrial stress as potential mechanisms. These pathways were analyzed both in vivo (C57BL/6J mice treated with the abovementioned drugs or vehicle for 16 weeks) and in vitro (in Hep3B cells). Mice treated with BIC exhibited higher glucose levels and a slower decrease during a glucose tolerance test. Functional enrichment analyses of livers from antiretroviral-treated mice revealed that only BIC altered the cellular response to insulin and induced a gluconeogenic-favoring profile, with Fgf21 playing a significant role. In vitro, BIC significantly reduced hepatocyte glucose uptake in a concentration-dependent manner, both under basal conditions and post-insulin stimulation, while the other drugs produced no significant changes. Hep3B cells treated with clinically relevant concentrations of BIC exhibited significant alterations in the mRNA expression of enzymes related to glucose metabolism. Both DTG and BIC reduced mitochondrial dehydrogenase activity, but only BIC increased reactive oxygen species, mitochondrial membrane potential, and cellular granularity, thereby indicating mitochondrial stress. BIC promoted mitochondrial dysfunction, modified carbohydrate metabolism and glucose consumption in hepatocytes, and altered glucose tolerance and gluconeogenesis regulation in mice. These findings suggest that BIC contributes to insulin resistance and diabetes in people living with HIV, warranting clinical studies to clarify its association with carbohydrate metabolism disorders.

FoxO1/Rictor axis induces a non-genetic adaptation to Ibrutinib via Akt activation in chronic lymphocytic leukemia

BTK inhibitor therapy induces peripheral blood lymphocytosis in chronic lymphocytic leukemia (CLL) lasting for several months. It remains unclear whether non-genetic adaptation mechanisms exist, allowing CLL cells' survival during BTK inhibitor-induced lymphocytosis and/or playing a role in therapy resistance. We show that in approximately 70 % of CLL cases, ibrutinib treatment in vivo increases Akt activity above pre-therapy levels within several weeks, leading to compensatory CLL cell survival and a more prominent lymphocytosis on therapy. Ibrutinib-induced Akt phosphorylation (pAktS473) is caused by the upregulation of FoxO1 transcription factor, which induces expression of Rictor, an assembly protein for mTORC2 protein complex that directly phosphorylates Akt at serine 473 (S473). Knock-out or inhibition of FoxO1 or Rictor led to a dramatic decrease in Akt phosphorylation and growth disadvantage for malignant B cells in the presence of ibrutinib (or PI3K inhibitor idelalisib) in vitro and in vivo. FoxO1/Rictor/pAktS473 axis represents an early non-genetic adaptation to BCR inhibitor therapy not requiring PI3Kδ or BTK kinase activity. We further demonstrate that FoxO1 can be targeted therapeutically, and its inhibition induces CLL cells' apoptosis alone or in combination with BTK inhibitors (ibrutinib, acalabrutinib, pirtobrutinib) and blocks their proliferation triggered by T-cell factors (CD40L, IL-4, and IL-21).

C-Phycocyanin: A Phycobiliprotein from Spirulina with Metabolic Syndrome and Oxidative Stress Effects

Spirulina maxima is a cyanobacterium considered a "superfood" due to its metabolites and nutrient content. These include a complex mixture of minerals, vitamins, fatty acids, proteins, and accessory pigments. In recent years, it has positioned itself as a promising source of bioactive molecules for the treatment of several diseases, including metabolic syndrome, coronary diseases, cancer, and the improvement of health modulating oxidative stress. C-Phycocyanin (C-PC) is a photosynthetic pigment from green-blue cyanobacterium and the most abundant phycobiliprotein in the Spirulina genus with various pharmacological properties attributed due to its antioxidant capacity but has no specific cellular target. This has made it a molecule of great interest in biomedical research. This review focuses on the pharmacological effects and the benefits on metabolic syndrome and oxidative stress of C-PC.

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.

Forkhead box O1 in metabolic dysfunction-associated fatty liver disease: molecular mechanisms and drug research

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a chronic liver disease that progresses from hepatic steatosis to non-alcoholic steatohepatitis, cirrhosis, and liver cancer, posing a huge burden on human health. Existing research has confirmed that forkhead box O1 (FOXO1), as a member of the FOXO transcription factor family, is upregulated in MAFLD. Its activity is closely related to nuclear-cytoplasmic shuttling and various post-translational modifications including phosphorylation, acetylation, and methylation. FOXO1 mediates the progression of MAFLD by regulating glucose metabolism, lipid metabolism, insulin resistance, oxidative stress, hepatic fibrosis, hepatocyte autophagy, apoptosis, and immune inflammation. This article elaborates on the regulatory role of FOXO1 in MAFLD, providing a summary and new insights for the current status of drug research and targeted therapies for MAFLD.

Lycopene Promotes Osteogenesis and Reduces Adipogenesis through Regulating FoxO1/PPARγ Signaling in Ovariectomized Rats and Bone Marrow Mesenchymal Stem Cells

Recent interest in preventing the development of osteoporosis has focused on the regulation of redox homeostasis. However, the action of lycopene (LYC), a strong natural antioxidant compound, on osteoporotic bone loss remains largely unknown. Here, we show that oral administration of LYC to OVX rats for 12 weeks reduced body weight gain, improved lipid metabolism, and preserved bone quality. In addition, LYC treatment inhibited ROS overgeneration in serum and bone marrow in OVX rats, and in BMSCs upon H2O2 stimulation, leading to inhibiting adipogenesis and promoting osteogenesis during bone remodeling. At the molecular level, LYC improved bone quality via an increase in the expressions of FoxO1 and Runx2 and a decrease in the expressions of PPARγ and C/EBPα in OVX rats and BMSCs. Collectively, these findings suggest that LYC attenuates osteoporotic bone loss through promoting osteogenesis and inhibiting adipogenesis via regulation of the FoxO1/PPARγ pathway driven by oxidative stress, presenting a novel strategy for osteoporosis management.

Exploring the Potential of Natural Products as FoxO1 Inhibitors: an In Silico Approach

FoxO1, a member of the Forkhead transcription factor family subgroup O (FoxO), is expressed in a range of cell types and is crucial for various pathophysiological processes, such as apoptosis and inflammation. While FoxO1's roles in multiple diseases have been recognized, the target has remained largely unexplored due to the absence of cost-effective and efficient inhibitors. Therefore, there is a need for natural FoxO1 inhibitors with minimal adverse effects. In this study, docking, MMGBSA, and ADMET analyses were performed to identify natural compounds that exhibit strong binding affinity to FoxO1. The top candidates were then subjected to molecular dynamics (MD) simulations. A natural product library was screened for interaction with FoxO1 (PDB ID- 3CO6) using the Glide module of the Schrödinger suite. In silico ADMET profiling was conducted using SwissADME and pkCSM web servers. Binding free energies of the selected compounds were assessed with the Prime-MMGBSA module, while the dynamics of the top hits were analyzed using the Desmond module of the Schrödinger suite. Several natural products demonstrated high docking scores with FoxO1, indicating their potential as FoxO1 inhibitors. Specifically, the docking scores of neochlorogenic acid and fraxin were both below -6.0. These compounds also exhibit favorable drug-like properties, and a 25 ns MD study revealed a stable interaction between fraxin and FoxO1. Our findings highlight the potential of various natural products, particularly fraxin, as effective FoxO1 inhibitors with strong binding affinity, dynamic stability, and suitable ADMET profiles.

Regulation of sirt1 and foxO1 in glucose metabolism of Megalobrama amblycephala

Both silent information regulator 2 homolog 1 (sirt1) and forkhead box transcription factor 1 (foxO1) are crucial transcription factors involved in glucolipid metabolism and energy regulation. The presnt study aimed to understand their regulatory roles in glucose metabolism. Molecular cloning and sequencing of sirt1 gene of Megalobrama amblycephala (masirt1) was conducted and cellular localization of both the factors were analysed. Their effects and action patterns in the glucose metabolism of Megalobrama amblycephala (M. amblycephala) were investigated through acute and long-term glucose tolerance assays. The results revealed that the full-length masirt1 cDNA sequence was 2350 bp and closely related to Sinocyclocheilus rhinocerous. Sirt1 and foxO1 were found to be mutually dependent and localized in the nucleus. Acute glucose tolerance tests revealed that the expression levels of both factors in the liver of M. amblycephala showed an initial increase followed by a decrease. Plasma glucose levels in M. amblycephala significantly increased at 2 and 12 h (P < 0.05). In a long-term breeding experiment with high-sugar feeding, the expressions of the sirt1 and foxO1 genes in the kidney and intestine of M. amblycephala exhibited synergistic changes. The 51WS groups had significantly higher levels of sirt1 and foxO1 gene expression in the kidney and intestine compared to the 0WS and 17WS groups (P < 0.05). Overall, masirt1 is evolutionarily highly conserved, and the interaction site of sirt1 and foxO1 is located in the nucleus. In long-term hyperglycemic regulation, sirt1 and foxO1 exhibit synergistic regulatory effects in the kidney and intestine of M. amblycephala. This study provides insights into how sirt1 and foxO1 regulate glucose metabolism in M. amblycephala.

The FOXO1/G6PC axis promotes gastric cancer progression and mediates 5-fluorouracil resistance by targeting the PI3K/AKT/mTOR signaling pathway

Gastric cancer (GC) is a prevalent malignancy of the digestive system. Distant metastasis and chemotherapy resistance are the crucial obstacles to prognosis in GC. Recent research has discovered that the glucose-6-phosphatase catalytic subunit (G6PC) plays an important role in tumor malignant development. However, little evidence has highlighted its role in GC. Herein, through a comprehensive analysis including profiling of tissue samples and functional validation in vivo and in vitro, we identify G6PC as a crucial factor in GC tumorigenesis. Importantly, we found that the FOXO1/G6PC axis could accelerate GC cell proliferation, metastasis, and 5-Fluorouracil (5-FU) resistance by targeting the PI3K/AKT/mTOR signaling pathway, implicating that as a prospective therapeutic approach in GC.

Artesunate improves glucose and lipid metabolism in db/db mice by regulating the metabolic profile and the MAPK/PI3K/Akt signalling pathway

BACKGROUND

Diabetes is a metabolic disorder characterized by chronic hyperglycaemia. Chronic metabolic abnormalities and long-term hyperglycaemia may result in a wide range of acute and chronic consequences. Previous studies have demonstrated that artesunate(ART) has antidiabetic, anti-inflammatory, antiatherosclerotic, and other beneficial effects, but the specific regulatory mechanism is not completely clear.

AIM

This study investigated the effects of ART on metabolic disorders in type 2 diabetes mellitus (T2DM) model db/db mice and explored the underlying mechanisms involved.

METHODS

C57BL/KsJ-db/db mice were used to identify the targets and molecular mechanism of ART. Metabolomic methods were used to evaluate the efficacy of ART in improving T2DM-related metabolic disorders. Network pharmacology and transcriptomic sequencing were used to analyse the targets and pathways of ART in T2DM. Finally, molecular biology experiments were performed to verify the key targets and pathways selected by network pharmacology and transcriptomic analyses.

RESULTS

After a 7-week ART intervention (160 mg/kg), the glucose and lipid metabolism levels of the db/db mice improved. Additionally, the oxidative stress indices, namely, the MDA and SOD levels, significantly improved (p<0.01). Linoleic acid and glycerophospholipid metabolism, amino acid metabolism, bile acid synthesis, and purine metabolism disorders in db/db mice were partially corrected after ART treatment. Network pharmacology analysis identified important targets of ART for the treatment of metabolic disorders in T2DM . These targets are involved in key signalling pathways, including the highest scores observed for the PI3K/Akt signalling pathway. Transcriptomic analysis revealed that ART could activate the MAPK signalling pathway and two key gene targets, HGK and GADD45. Immunoblotting revealed that ART increases p-PI3K, p-AKT, Glut2, and IRS1 protein expression and suppresses the phosphorylation of p38, ERK1/2, and JNK, returning HGK and GADD45 to their preartesunate levels.

CONCLUSION

Treatment of db/db mice with 160 mg/kg ART for 7 weeks significantly reduced fasting blood glucose and lipid levels. It also improved metabolic imbalances in amino acids, lipids, purines, and bile acids, thereby improving metabolic disorders. These effects are achieved by activating the PI3K/AKT pathway and inhibiting the MAPK pathway, thus demonstrating the efficacy of the drug.

FOXO1 reshapes neutrophils to aggravate acute brain damage and promote late depression after traumatic brain injury

BACKGROUND

Neutrophils are traditionally viewed as first responders but have a short onset of action in response to traumatic brain injury (TBI). However, the heterogeneity, multifunctionality, and time-dependent modulation of brain damage and outcome mediated by neutrophils after TBI remain poorly understood.

METHODS

Using the combined single-cell transcriptomics, metabolomics, and proteomics analysis from TBI patients and the TBI mouse model, we investigate a novel neutrophil phenotype and its associated effects on TBI outcome by neurological deficit scoring and behavioral tests. We also characterized the underlying mechanisms both in vitro and in vivo through molecular simulations, signaling detections, gene expression regulation assessments [including dual-luciferase reporter and chromatin immunoprecipitation (ChIP) assays], primary cultures or co-cultures of neutrophils and oligodendrocytes, intracellular iron, and lipid hydroperoxide concentration measurements, as well as forkhead box protein O1 (FOXO1) conditional knockout mice.

RESULTS

We identified that high expression of the FOXO1 protein was induced in neutrophils after TBI both in TBI patients and the TBI mouse model. Infiltration of these FOXO1high neutrophils in the brain was detected not only in the acute phase but also in the chronic phase post-TBI, aggravating acute brain inflammatory damage and promoting late TBI-induced depression. In the acute stage, FOXO1 upregulated cytoplasmic Versican (VCAN) to interact with the apoptosis regulator B-cell lymphoma-2 (BCL-2)-associated X protein (BAX), suppressing the mitochondrial translocation of BAX, which mediated the antiapoptotic effect companied with enhancing interleukin-6 (IL-6) production of FOXO1high neutrophils. In the chronic stage, the "FOXO1-transferrin receptor (TFRC)" mechanism contributes to FOXO1high neutrophil ferroptosis, disturbing the iron homeostasis of oligodendrocytes and inducing a reduction in myelin basic protein, which contributes to the progression of late depression after TBI.

CONCLUSIONS

FOXO1high neutrophils represent a novel neutrophil phenotype that emerges in response to acute and chronic TBI, which provides insight into the heterogeneity, reprogramming activity, and versatility of neutrophils in TBI.

Lipoteichoic acid restrains macrophage senescence via β-catenin/FOXO1/REDD1 pathway in age-related osteoporosis

Osteoporosis and its related fractures are common causes of morbidity and mortality in older adults, but its underlying molecular and cellular mechanisms remain largely unknown. In this study, we found that lipoteichoic acid (LTA) treatment could ameliorate age-related bone degeneration and attenuate intramedullary macrophage senescence. FOXO1 signaling, which was downregulated and deactivated in aging macrophages, played a key role in the process. Blocking FOXO1 signaling caused decreased REDD1 expression and increased phosphorylation level of mTOR, a major driver of aging, as well as aggravated bone loss and deteriorated macrophage senescence. Moreover, LTA elevated FOXO1 signaling through β-catenin pathway while β-catenin inhibition significantly suppressed FOXO1 signaling, promoted senescence-related protein expression, and accelerated bone degeneration and macrophage senescence. Our findings indicated that β-catenin/FOXO1/REDD1 signaling plays a physiologically significant role that protecting macrophages from senescence during aging.

Echinacoside alleviates glucocorticoid induce osteonecrosis of femoral head in rats through PI3K/AKT/FOXO1 pathway

Steroid-induced osteonecrosis of the femoral head (SONFH), caused by glucocorticoid (GC) administration, is known to exhibit a high incidence worldwide. Although osteoblast apoptosis has been reported as an important cytological basis of SONFH, the precise mechanism remains elusive. Echinacoside (Ech), a natural phenylethanoid glycoside, exerts multiple beneficial effects, such as facilitation of cell proliferation and anti-inflammatory and anticancer activities. Herein, we aimed to explore the regulatory mechanism underlying glucocorticoid-induced osteoblast apoptosis and determine the protective efficacy of Ech against SONFH. We comprehensively surveyed multiple public databases to identify SONFH-related genes. Using bioinformatics analysis, we identified that the PI3K/AKT/FOXO1 signaling pathway was most strongly associated with SONFH. We examined the protective effect of Ech against SONFH using in vivo and in vitro experiments. Specifically, dexamethasone (Dex) decreased p-PI3K and p-AKT levels, which were reversed following Ech addition. Validation of the PI3K inhibitor (LY294002) and molecular docking of Ech and PI3K/AKT further indicated that Ech could directly enhance PI3K/AKT activity to alleviate Dex-induced inhibition. Interestingly, Dex upregulated the expression of FOXO1, Bax, cleaved-caspase-9, and cleaved-caspase-3 and enhanced MC3T3-E1 apoptosis; application of Ech and siRNA-FOXO1 reversed these effects. In vitro, Ech decreased the number of empty osteocytic lacunae, reduced TUNEL and FOXO1 positive cells, and improved bone microarchitecture. Our results provide robust evidence that PI3K/AKT/FOXO1 plays a crucial role in the development of SONFH. Moreover, Ech may be a promising candidate drug for the treatment of SONFH.

In silico and in vitro analyses of a novel FoxO1 agonist reducing Aβ levels via downregulation of BACE1

AIMS

FoxO1 is an important target in the treatment of Alzheimer's disease (AD). However, FoxO1-specific agonists and their effects on AD have not yet been reported. This study aimed to identify small molecules that upregulate the activity of FoxO1 to attenuate the symptoms of AD.

METHODS

FoxO1 agonists were identified by in silico screening and molecular dynamics simulation. Western blotting and reverse transcription-quantitative polymerase chain reaction assays were used to assess protein and gene expression levels of P21, BIM, and PPARγ downstream of FoxO1 in SH-SY5Y cells, respectively. Western blotting and enzyme-linked immunoassays were performed to explore the effect of FoxO1 agonists on APP metabolism.

RESULTS

N-(3-methylisothiazol-5-yl)-2-(2-oxobenzo[d]oxazol-3(2H)-yl) acetamide (compound D) had the highest affinity for FoxO1. Compound D activated FoxO1 and regulated the expression of its downstream target genes, P21, BIM, and PPARγ. In SH-SY5Y cells treated with compound D, BACE1 expression levels were downregulated, and the levels of Aβ1-40 and Aβ1-42 were also reduced.

CONCLUSIONS

We present a novel small-molecule FoxO1 agonist with good anti-AD effects. This study highlights a promising strategy for new drug discovery for AD.

Enhanced anticancer synergy of LOM612 in combination with selinexor: FOXO1 nuclear translocation-mediated inhibition of Wnt/β-catenin signaling pathway in breast cancer

BACKGROUND

The intricate relationship between Forkhead box O1 (FOXO1), a well-established tumor suppressor, and breast cancer (BC) remains partially elucidated. This study aims to investigate the mechanistic role of FOXO1 nuclear localization in the context of BC.

METHODS

In vitro experiments employed BC cell lines MCF-7 and MDA-MB-175 treated with LOM612, a small molecule activator of FOXO nuclear-cytoplasmic shuttling, and selinexor, an exportin 1 inhibitor. Nuclear accumulation of FOXO1, its interaction with β-catenin, and expressions of key proteins like V-Myc avian myelocytomatosis viral oncogene homolog (c-Myc), cyclin D1 and apoptosis markers were assessed. In vivo, the effects of LOM612 and selinexor were studied using MCF-7 cell-derived xenografts (CDX).

RESULTS

Treatment with LOM612 exhibited a significant enhancement in nuclear accumulation of FOXO1 within BC cells. This effect coincided with suppressed migratory behavior and heightened apoptosis susceptibility in these cells. Mechanistically, LOM612 orchestrated FOXO1 to compete with transcription factors (TCF) for binding to β-catenin in the nucleus, leading to reduced c-Myc and cyclin D1 expressions, along with elevated levels of apoptosis-related proteins. Similar trends were observed in CDX models, where LOM612 effectively suppressed tumor growth, increased FOXO1 nuclear localization, and downregulated c-Myc and cyclin D1 expressions. Importantly, selinexor synergistically reinforced the therapeutic effects of LOM612 both in vitro and in vivo.

CONCLUSIONS

Collectively, this study underscores the potential of combining LOM612 and selinexor as an efficacious anti-BC strategy. The underlying mechanism involves FOXO1's nuclear translocation, which disrupts TCF-β-catenin interactions, thus indirectly inhibiting the Wnt/β-catenin signaling pathway.

FOXO1 reduces STAT3 activation and causes impaired mitochondrial quality control in diabetic cardiomyopathy

AIMS

To investigate the role of FOXO1 in STAT3 activation and mitochondrial quality control in the diabetic heart.

METHODS

Type 1 diabetes mellitus (T1DM) was induced in rats by a single intraperitoneal injection of 60 mg · kg-1 streptozotocin (STZ), while type 2 diabetes mellitus (T2DM) was induced in rats with a high-fat diet through intraperitoneal injection of 35 mg · kg-1 STZ. Primary neonatal mouse cardiomyocytes and H9c2 cells were exposed to low glucose (5.5 mM) or high glucose (HG; 30 mM) with or without treatment with the FOXO1 inhibitor AS1842856 (1 μM) for 24 hours. In addition, the diabetic db/db mice (aged 8 weeks) and sex- and age-matched non-diabetic db/+ mice were treated with vehicle or AS1842856 by oral gavage for 15 days at a dose of 5 mg · kg-1  · d-1 .

RESULTS

Rats with T1DM or T2DM had excessive cardiac FOXO1 activation, accompanied by decreased STAT3 activation. Immunofluorescence and immunoprecipitation analysis showed colocalization and association of FOXO1 and STAT3 under basal conditions in isolated cardiomyocytes. Selective inhibition of FOXO1 activation by AS1842856 or FOXO1 siRNA transfection improved STAT3 activation, mitophagy and mitochondrial fusion, and decreased mitochondrial fission in isolated cardiomyocytes exposed to HG. Transfection with STAT3 siRNA further reduced mitophagy, mitochondrial fusion and increased mitochondrial fission in HG-treated cardiomyocytes. AS1842856 alleviated cardiac dysfunction, pathological damage and improved STAT3 activation, mitophagy and mitochondrial dynamics in diabetic db/db mice. Additionally, AS1842856 improved mitochondrial function indicated by increased mitochondrial membrane potential and adenosine triphosphate production and decreased mitochondrial reactive oxygen species production in isolated cardiomyocytes exposed to HG.

CONCLUSIONS

Excessive FOXO1 activation during diabetes reduces STAT3 activation, with subsequent impairment of mitochondrial quality, ultimately promoting the development of diabetic cardiomyopathy.

Examining the biological pathways underlying clinical heterogeneity in Sjogren's syndrome: proteomic and network analysis

OBJECTIVES

Stratification approaches are vital to address clinical heterogeneity in Sjogren's syndrome (SS). We previously described that the Newcastle Sjogren's Stratification Tool (NSST) identified four distinct clinical subtypes of SS. We performed proteomic and network analysis to analyse the underlying pathobiology and highlight potential therapeutic targets for different SS subtypes.

METHOD

We profiled serum proteins using O-link technology of 180 SS subjects. We used 5 O-link proteomics panels which included a total of 454 unique proteins. Network reconstruction was performed using the ARACNE algorithm, with differential expression estimates overlaid on these networks to reveal the key subnetworks of differential expression. Furthermore, data from a phase III trial of tocilizumab in SS were reanalysed by stratifying patients at baseline using NSST.

RESULTS

Our analysis highlights differential expression of chemokines, cytokines and the major autoantigen TRIM21 between the SS subtypes. Furthermore, we observe differential expression of several transcription factors associated with energy metabolism and redox balance namely APE1/Ref-1, FOXO1, TIGAR and BACH1. The differentially expressed proteins were inter-related in our network analysis, supporting the concept that distinct molecular networks underlie the clinical subtypes of SS. Stratification of patients at baseline using NSST revealed improvement of fatigue score only in the subtype expressing the highest levels of serum IL-6.

CONCLUSIONS

Our data provide clues to the pathways contributing to the glandular and non-glandular manifestations of SS and to potential therapeutic targets for different SS subtypes. In addition, our analysis highlights the need for further exploration of altered metabolism and mitochondrial dysfunction in the context of SS subtypes.

Reepithelialization of Diabetic Skin and Mucosal Wounds Is Rescued by Treatment With Epigenetic Inhibitors

Wound healing is a complex, highly regulated process and is substantially disrupted by diabetes. We show here that human wound healing induces specific epigenetic changes that are exacerbated by diabetes in an animal model. We identified epigenetic changes and gene expression alterations that significantly reduce reepithelialization of skin and mucosal wounds in an in vivo model of diabetes, which were dramatically rescued in vivo by blocking these changes. We demonstrate that high glucose altered FOXO1-matrix metallopeptidase 9 (MMP9) promoter interactions through increased demethylation and reduced methylation of DNA at FOXO1 binding sites and also by promoting permissive histone-3 methylation. Mechanistically, high glucose promotes interaction between FOXO1 and RNA polymerase-II (Pol-II) to produce high expression of MMP9 that limits keratinocyte migration. The negative impact of diabetes on reepithelialization in vivo was blocked by specific DNA demethylase inhibitors in vivo and by blocking permissive histone-3 methylation, which rescues FOXO1-impaired keratinocyte migration. These studies point to novel treatment strategies for delayed wound healing in individuals with diabetes. They also indicate that FOXO1 activity can be altered by diabetes through epigenetic changes that may explain other diabetic complications linked to changes in diabetes-altered FOXO1-DNA interactions.

ARTICLE HIGHLIGHTS

FOXO1 expression in keratinocytes is needed for normal wound healing. In contrast, FOXO1 expression interferes with the closure of diabetic wounds. Using matrix metallopeptidase 9 as a model system, we found that high glucose significantly increased FOXO1-matrix metallopeptidase 9 interactions via increased DNA demethylation, reduced DNA methylation, and increased permissive histone-3 methylation in vitro. Inhibitors of DNA demethylation and permissive histone-3 methylation improved the migration of keratinocytes exposed to high glucose in vitro and the closure of diabetic skin and mucosal wounds in vivo. Inhibition of epigenetic enzymes that alter FOXO1-induced gene expression dramatically improves diabetic healing and may apply to other conditions where FOXO1 has a detrimental role in diabetic complications.

Gut bacterium promotes host fitness in special ecological niche by affecting sugar metabolism in Drosophila suzukii

As an important fruit pest of global significance, Drosophila suzukii occupies a special ecological niche, with the characteristics of high sugar and low protein contents. This niche differs from those occupied by other fruit-damaging Drosophila species. Gut bacteria substantially impact the physiology and ecology of insects. However, the contribution of gut microbes to the fitness of D. suzukii in their special ecological niche remains unclear. In this study, the effect of Klebsiella oxytoca on the development of D. suzukii was examined at physiological and molecular levels. The results showed that, after the removal of gut microbiota, the survival rate and longevity of axenic D. suzukii decreased significantly. Reintroduction of K. oxytoca to the midgut of D. suzukii advanced the development level of D. suzukii. The differentially expressed genes and metabolites between axenic and K. oxytoca-reintroduced D. suzukii were enriched in the pathways of carbohydrate metabolism. This advancement was achieved through an increased glycolysis rate and the regulation of the transcript level of key genes in the glycolysis/gluconeogenesis pathway. Klebsiella oxytoca is likely to play an important role in increasing host fitness in their high-sugar ecological niche by stimulating the glycolysis/gluconeogenesis pathway. As a protein source, bacteria can also provide direct nutrition for D. suzukii, which depends on the quantity or biomass of K. oxytoca. This result may provide a new target for controlling D. suzukii by inhibiting sugar metabolism through eliminating the effect of K. oxytoca and thus disrupting the balance of gut microbial communities.

Acne Transcriptomics: Fundamentals of Acne Pathogenesis and Isotretinoin Treatment

This review on acne transcriptomics allows for deeper insights into the pathogenesis of acne and isotretinoin's mode of action. Puberty-induced insulin-like growth factor 1 (IGF-1), insulin and androgen signaling activate the kinase AKT and mechanistic target of rapamycin complex 1 (mTORC1). A Western diet (hyperglycemic carbohydrates and milk/dairy products) also co-stimulates AKT/mTORC1 signaling. The AKT-mediated phosphorylation of nuclear FoxO1 and FoxO3 results in their extrusion into the cytoplasm, a critical switch which enhances the transactivation of lipogenic and proinflammatory transcription factors, including androgen receptor (AR), sterol regulatory element-binding transcription factor 1 (SREBF1), peroxisome proliferator-activated receptor γ (PPARγ) and signal transducer and activator of transcription 3 (STAT3), but reduces the FoxO1-dependent expression of GATA binding protein 6 (GATA6), the key transcription factor for infundibular keratinocyte homeostasis. The AKT-mediated phosphorylation of the p53-binding protein MDM2 promotes the degradation of p53. In contrast, isotretinoin enhances the expression of p53, FoxO1 and FoxO3 in the sebaceous glands of acne patients. The overexpression of these proapoptotic transcription factors explains isotretinoin's desirable sebum-suppressive effect via the induction of sebocyte apoptosis and the depletion of BLIMP1(+) sebocyte progenitor cells; it also explains its adverse effects, including teratogenicity (neural crest cell apoptosis), a reduced ovarian reserve (granulosa cell apoptosis), the risk of depression (the apoptosis of hypothalamic neurons), VLDL hyperlipidemia, intracranial hypertension and dry skin.

Cornerstone Cellular Pathways for Metabolic Disorders and Diabetes Mellitus: Non-Coding RNAs, Wnt Signaling, and AMPK

Metabolic disorders and diabetes (DM) impact more than five hundred million individuals throughout the world and are insidious in onset, chronic in nature, and yield significant disability and death. Current therapies that address nutritional status, weight management, and pharmacological options may delay disability but cannot alter disease course or functional organ loss, such as dementia and degeneration of systemic bodily functions. Underlying these challenges are the onset of aging disorders associated with increased lifespan, telomere dysfunction, and oxidative stress generation that lead to multi-system dysfunction. These significant hurdles point to the urgent need to address underlying disease mechanisms with innovative applications. New treatment strategies involve non-coding RNA pathways with microRNAs (miRNAs) and circular ribonucleic acids (circRNAs), Wnt signaling, and Wnt1 inducible signaling pathway protein 1 (WISP1) that are dependent upon programmed cell death pathways, cellular metabolic pathways with AMP-activated protein kinase (AMPK) and nicotinamide, and growth factor applications. Non-coding RNAs, Wnt signaling, and AMPK are cornerstone mechanisms for overseeing complex metabolic pathways that offer innovative treatment avenues for metabolic disease and DM but will necessitate continued appreciation of the ability of each of these cellular mechanisms to independently and in unison influence clinical outcome.

FOXO1-regulated lncRNA CYP1B1-AS1 suppresses breast cancer cell proliferation by inhibiting neddylation

PURPOSE

Overactivated neddylation is considered to be a common event in cancer. Long non-coding RNAs (lncRNAs) can regulate cancer development by mediating post-translational modifications. However, the role of lncRNA in neddylation modification remains unclear.

METHODS

LncRNA cytochrome P450 family 1 subfamily B member 1 antisense RNA 1 (CYP1B1-AS1) expression in breast cancer tissues was evaluated by RT-PCR and TCGA BRCA data. Gain and loss of function experiments were performed to explore the role of CYP1B1-AS1 in breast cancer cell proliferation and apoptosis in vitro and in vivo. Luciferase assay, CHIP-qPCR assay, transcriptome sequencing, RNA-pulldown assay, mass spectrometry, RIP-PCR and Western blot were used to investigate the regulatory factors of CYP1B1-AS1 expression and the molecular mechanism of CYP1B1-AS1 involved in neddylation modification.

RESULTS

We found that CYP1B1-AS1 was down-regulated in breast cancer tissues and correlated with prognosis. In vivo and in vitro functional experiments confirmed that CYP1B1-AS1 inhibited cell proliferation and induced apoptosis. Mechanistically, CYP1B1-AS1 was regulated by the transcription factor, forkhead box O1 (FOXO1), and could be upregulated by inhibiting the PI3K/FOXO1 pathway. Moreover, CYP1B1-AS1 bound directly to NEDD8 activating enzyme E1 subunit 1 (NAE1) to regulate protein neddylation.

CONCLUSION

This study reports for the first time that CYP1B1-AS1 inhibits protein neddylation to affect breast cancer cell proliferation, which provides a new strategy for the treatment of breast cancer by lncRNA targeting neddylation modification.

Decreased HAT1 expression in granulosa cells disturbs oocyte meiosis during mouse ovarian aging

BACKGROUND

With advanced maternal age, abnormalities during oocyte meiosis increase significantly. Aneuploidy is an important reason for the reduction in the quality of aged oocytes. However, the molecular mechanism of aneuploidy in aged oocytes is far from understood. Histone acetyltransferase 1 (HAT1) has been reported to be essential for mammalian development and genome stability, and involved in multiple organ aging. Whether HAT1 is involved in ovarian aging and the detailed mechanisms remain to be elucidated.

METHODS

The level of HAT1 in aged mice ovaries was detected by immunohistochemical and immunoblotting. To explore the function of HAT1 in the process of mouse oocyte maturation, we used Anacardic Acid (AA) and small interfering RNAs (siRNA) to culture cumulus-oocyte complexes (COCs) from ICR female mice in vitro and gathered statistics of germinal vesicle breakdown (GVBD), the first polar body extrusion (PBE), meiotic defects, aneuploidy, 2-cell embryos formation, and blastocyst formation rate. Moreover, the human granulosa cell (GC)-like line KGN cells were used to investigate the mechanisms of HAT1 in this progress.

RESULTS

HAT1 was highly expressed in ovarian granulosa cells (GCs) from young mice and the expression of HAT1 was significantly decreased in aged GCs. AA and siRNAs mediated inhibition of HAT1 in GCs decreased the PBE rate, and increased meiotic defects and aneuploidy in oocytes. Further studies showed that HAT1 could acetylate Forkhead box transcription factor O1 (FoxO1), leading to the translocation of FoxO1 into the nucleus. Resultantly, the translocation of acetylated FoxO1 increased the expression of amphiregulin (AREG) in GCs, which plays a significant role in oocyte meiosis.

CONCLUSION

The present study suggests that decreased expression of HAT1 in GCs is a potential reason corresponding to oocyte age-related meiotic defects and provides a potential therapeutic target for clinical intervention to reduce aneuploid oocytes.

FoxO1 as a tissue-specific therapeutic target for type 2 diabetes

Forkhead box O (FoxO) proteins are transcription factors that mediate many aspects of physiology and thus have been targeted as therapeutics for several diseases including metabolic disorders such as type 2 diabetes mellitus (T2D). The role of FoxO1 in metabolism has been well studied, but recently FoxO1's potential for diabetes prevention and therapy has been debated. For example, studies have shown that increased FoxO1 activity in certain tissue types contributes to T2D pathology, symptoms, and comorbidities, yet in other tissue types elevated FoxO1 has been reported to alleviate symptoms associated with diabetes. Furthermore, studies have reported opposite effects of active FoxO1 in the same tissue type. For example, in the liver, FoxO1 contributes to T2D by increasing hepatic glucose production. However, FoxO1 has been shown to either increase or decrease hepatic lipogenesis as well as adipogenesis in white adipose tissue. In skeletal muscle, FoxO1 reduces glucose uptake and oxidation, promotes lipid uptake and oxidation, and increases muscle atrophy. While many studies show that FoxO1 lowers pancreatic insulin production and secretion, others show the opposite, especially in response to oxidative stress and inflammation. Elevated FoxO1 in the hypothalamus increases the risk of developing T2D. However, increased FoxO1 may mitigate Alzheimer's disease, a neurodegenerative disease strongly associated with T2D. Conversely, accumulating evidence implicates increased FoxO1 with Parkinson's disease pathogenesis. Here we review FoxO1's actions in T2D conditions in metabolic tissues that abundantly express FoxO1 and highlight some of the current studies targeting FoxO1 for T2D treatment.

A comprehensive review of the effects of resveratrol on glucose metabolism: unveiling the molecular pathways and therapeutic potential in diabetes management

Resveratrol, a naturally occurring polyphenolic compound predominantly found in red wine and grapes, has garnered attention for its potential role in regulating carbohydrate digestion, glucose absorption, and metabolism. This review aims to deliver a comprehensive analysis of the molecular mechanisms and therapeutic potential of resveratrol in influencing vital processes in glucose homeostasis. These processes include carbohydrate digestion, glucose absorption, glycogen storage, insulin secretion, glucose metabolism in muscle cells, and triglyceride synthesis in adipocytes.The goal of this review is to offer an in-depth understanding of the multifaceted effects of resveratrol on glucose metabolism. By doing so, it presents valuable insights into its potential applications for preventing and treating metabolic disorders. This comprehensive examination of resveratrol's impact on glucose management will contribute to the growing body of knowledge on this promising natural compound, which may benefit researchers, healthcare professionals, and individuals interested in metabolic disorder prevention and treatment.

Eryngium billardieri extract affects cardiac gene expression of master regulators of cardiomyaopathy in rats with high fatdiet-induced insulin resistance

BACKGROUND

For years, numerous studies have focused on identifying approaches to increase insulin sensitivity by modifying the signaling factors. In the present study, we examined the effects of Eryngium billardieri extract, as an anti-diabetic herbal medication, on the heart mRNA level of Akt serine/threonine kinase (Akt), mechanistic target of rapamycin kinase (mTOR), peroxisome proliferator-activated receptor gamma (PPARγ), and Forkhead box o1 (Foxo1) in rats with high-fat diet (HFD)-induced insulin resistance (IR). We also assessed the anti-diabetic effects of E. billardieri extract in rats with insulin resistance.

METHODS

Twenty-seven male Wistar rats were divided into two groups. Nine rats were fed a normal diet (control group), and 18 rats were fed an HFD for 13 weeks (HFD group). To confirm the induction of insulin resistance, the oral glucose tolerance test (OGTT) was performed and homeostatic model assessment for insulin resistance (HOMA-IR) was calculated. Then rats with IR were randomly divided into the following groups: the HFD group, which continued an HFD, and the group treated with E. billardieri extract, which received the extract at a concentration of 50 mg/kg for 30 days. On the 30th day, the animals were sacrificed and serum samples were collected for biochemistry analyses. Furthermore, the expression of Akt, mTOR, PPARγ, and Foxo1 was measured in heart tissue using the real-time polymerase chain reaction (PCR) method.

RESULTS

Real-time PCR analyses revealed that an HFD can significantly decrease the expression level of Akt, mTOR, and PPARγ in the heart tissue. However, an HFD significantly increased the expression level of Foxo1 in the HFD group compared to the control group (P < 0.05). In addition, our data showed that the administration of E. billardieri extract significantly enhanced the mRNA levels of Akt, PPARγ, and mTOR in the heart tissue compared to the HFD group (P < 0.05), while it significantly decreased the Foxo1 mRNA levels (P < 0.01).

CONCLUSION

Given that Akt, mTOR, PPARγ, and Foxo1 are critical factors in insulin resistance, the present study suggests that E. billardieri could probably be used as an alternative treatment for IR as a major feature of metabolic syndrome.

Innovative therapeutic strategies for cardiovascular disease

As a significant non-communicable disease, cardiovascular disease is the leading cause of death for both men and women, comprises almost twenty percent of deaths in most racial and ethnic groups, can affect greater than twenty-five million individuals worldwide over the age of twenty, and impacts global economies with far-reaching financial challenges. Multiple factors can affect the onset of cardiovascular disease that include high serum cholesterol levels, elevated blood pressure, tobacco consumption and secondhand smoke exposure, poor nutrition, physical inactivity, obesity, and concurrent diabetes mellitus. Yet, addressing any of these factors cannot completely eliminate the onset or progression of cardiovascular disorders. Novel strategies are necessary to target underlying cardiovascular disease mechanisms. The silent mating type information regulation 2 homolog 1 (Saccharomyces cerevisiae) (SIRT1), a histone deacetylase, can limit cardiovascular injury, assist with stem cell development, oversee metabolic homeostasis through nicotinamide adenine dinucleotide (NAD+) pathways, foster trophic factor protection, and control cell senescence through the modulation of telomere function. Intimately tied to SIRT1 pathways are mammalian forkhead transcription factors (FoxOs) which can modulate cardiac disease to reduce oxidative stress, repair microcirculation disturbances, and reduce atherogenesis through pathways of autophagy, apoptosis, and ferroptosis. AMP activated protein kinase (AMPK) also is critical among these pathways for the oversight of cardiac cellular metabolism, insulin sensitivity, mitochondrial function, inflammation, and the susceptibility to viral infections such as severe acute respiratory syndrome coronavirus that can impact cardiovascular disease. Yet, the relationship among these pathways is both intricate and complex and requires detailed insight to successfully translate these pathways into clinical care for cardiovascular disorders.

miR-205-5p inhibits homocysteine-induced pulmonary microvascular endothelium dysfunction by targeting FOXO1

Homocysteine (Hcy) is a risk factor for multiple chronic diseases, and vascular endothelial cell injury has been regarded as the initiating step for this process. miRNAs are involved in Hcy-induced endothelial dysfunction, while the underlying mechanism and roles of miRNAs in pulmonary endothelial dysfunction induced by homocysteine are unknown. Here, we find that miR-205-5p alleviates pulmonary endothelial dysfunction by targeting FOXO1 in CBS +/‒ mice to protect against Hcy-induced pulmonary endothelial dysfunction. Mechanistically, we show that Hcy can lead to DNA hypermethylation of the miR-205-5p promoter due to the increased binding of DNMT1 to its promoter, which contributes to reduction of miR-205-5p expression. In summary, miR-205-5p promoter hypermethylation causes downregulation of miR-205-5p expression, resulting in a reduction in miR-205-5p binding to FOXO1 during homocysteine-induced pulmonary endothelial dysfunction. Our data indicate that miR-205-5p may be a potential therapeutic target against Hcy-induced pulmonary injury.

Cognitive Impairment in Multiple Sclerosis

Almost three million individuals suffer from multiple sclerosis (MS) throughout the world, a demyelinating disease in the nervous system with increased prevalence over the last five decades, and is now being recognized as one significant etiology of cognitive loss and dementia. Presently, disease modifying therapies can limit the rate of relapse and potentially reduce brain volume loss in patients with MS, but unfortunately cannot prevent disease progression or the onset of cognitive disability. Innovative strategies are therefore required to address areas of inflammation, immune cell activation, and cell survival that involve novel pathways of programmed cell death, mammalian forkhead transcription factors (FoxOs), the mechanistic target of rapamycin (mTOR), AMP activated protein kinase (AMPK), the silent mating type information regulation 2 homolog 1 (Saccharomyces cerevisiae) (SIRT1), and associated pathways with the apolipoprotein E (APOE-ε4) gene and severe acute respiratory syndrome coronavirus (SARS-CoV-2). These pathways are intertwined at multiple levels and can involve metabolic oversight with cellular metabolism dependent upon nicotinamide adenine dinucleotide (NAD+). Insight into the mechanisms of these pathways can provide new avenues of discovery for the therapeutic treatment of dementia and loss in cognition that occurs during MS.

Chronic Exposure to Chlorpyrifos Damages Thyroid Activity and Imbalances Hepatic Thyroid Hormones Signaling and Glucose Metabolism: Dependency of T3-FOXO1 Axis by Hyperglycemia

Early life exposure to Endocrine Disruptor Chemicals (EDCs), such as the organophosphate pesticide Chlorpyrifos (CPF), affects the thyroid activity and dependent process, including the glucose metabolism. The damage of thyroid hormones (THs) as a mechanism of action of CPF is underestimated because the studies rarely consider that TH levels and signaling are customized peripherally. Here, we investigated the impairment of metabolism/signaling of THs and lipid/glucose metabolism in the livers of 6-month-old mice, developmentally and lifelong exposed to 0.1, 1, and 10 mg/kg/die CPF (F1) and their offspring similarly exposed (F2), analyzing the levels of transcripts of the enzymes involved in the metabolism of T3 (Dio1), lipids (Fasn, Acc1), and glucose (G6pase, Pck1). Both processes were altered only in F2 males, affected by hypothyroidism and by a systemic hyperglycemia linked to the activation of gluconeogenesis in mice exposed to 1 and 10 mg/kg/die CPF. Interestingly, we observed an increase in active FOXO1 protein due to a decrease in AKT phosphorylation, despite insulin signaling activation. Experiments in vitro revealed that chronic exposure to CPF affected glucose metabolism via the direct modulation of FOXO1 activity and T3 levels in hepatic cells. In conclusion, we described different sex and intergenerational effects of CPF exposure on the hepatic homeostasis of THs, their signaling, and, finally, glucose metabolism. The data points to FOXO1-T3-glucose signaling as a target of CPF in liver.

A Systematic Approach to the Discovery of Protein-Protein Interaction Stabilizers

Dysregulation of protein-protein interactions (PPIs) commonly leads to disease. PPI stabilization has only recently been systematically explored for drug discovery despite being a powerful approach to selectively target intrinsically disordered proteins and hub proteins, like 14-3-3, with multiple interaction partners. Disulfide tethering is a site-directed fragment-based drug discovery (FBDD) methodology for identifying reversibly covalent small molecules. We explored the scope of disulfide tethering for the discovery of selective PPI stabilizers (molecular glues) using the hub protein 14-3-3σ. We screened complexes of 14-3-3 with 5 biologically and structurally diverse phosphopeptides derived from the 14-3-3 client proteins ERα, FOXO1, C-RAF, USP8, and SOS1. Stabilizing fragments were found for 4/5 client complexes. Structural elucidation of these complexes revealed the ability of some peptides to conformationally adapt to make productive interactions with the tethered fragments. We validated eight fragment stabilizers, six of which showed selectivity for one phosphopeptide client, and structurally characterized two nonselective hits and four fragments that selectively stabilized C-RAF or FOXO1. The most efficacious fragment increased 14-3-3σ/C-RAF phosphopeptide affinity by 430-fold. Disulfide tethering to the wildtype C38 in 14-3-3σ provided diverse structures for future optimization of 14-3-3/client stabilizers and highlighted a systematic method to discover molecular glues.

The role of FOXO1-mediated autophagy in the regulation of bone formation

Autophagy is essential for the maintenance of intracellular homeostasis, implicated in various biological processes. Forkhead box protein O1 (FOXO1) is regarded as a key mediator regulating skeletal development. Recent studies indicate that FOXO1 has a multifaceted role in autophagy regulation and dysregulation. Here, we aimed to elucidate the role of FOXO1-autophagy axis in osteogenesis. Osteoblast conditional Foxo1-knockout mice (Foxo1_OB^-/-, KO) and FOXO1 lentivirus overexpression (Len-FoxO1) model were constructed in vivo. Primary osteoblasts were isolated from KO and their wild-type (WT) littermates. And we also applied overexpression lentivirus to investigate the effects of FOXO1 in vitro. Using Micro-CT, fluorescence labeling detection, real-time qPCR and western blot analyses, we found that bone formation was promoted in Len-FOXO1 mice, which was impaired in KO group. Similarly, FOXO1 overexpression enhanced proliferation, migration and differentiation of osteoblasts, while FOXO1 ablation resulted in poor biological functions of osteoblasts. Through the investigation of autophagic process using mRFP-GFP-LC3 fluorescence labeling and co-immunoprecipitation, we observed that overexpression of FOXO1 initiated autophagy induction, with enhanced FOXO1 interaction with autophagy-related protein 7 (ATG7). On the contrary, FOXO1 knockout in osteoblasts impeded FOXO1-ATG7 conjugation, leading to impaired autophagic activity. Furthermore, inhibition of autophagy by chloroquine (CQ) could reverse favorable influences in bone formation induced by FOXO1 overexpression. Our findings confirmed that FOXO1 was an important regulator of bone formation and autophagy might be part of the underlying mechanisms, offering a significant avenue for the potential strategy in the treatment of bone-related disorders.

Regulation of Liver Glucose and Lipid Metabolism by Transcriptional Factors and Coactivators

The prevalence of nonalcoholic fatty liver disease (NAFLD) worldwide is on the rise and NAFLD is becoming the most common cause of chronic liver disease. In the USA, NAFLD affects over 30% of the population, with similar occurrence rates reported from Europe and Asia. This is due to the global increase in obesity and type 2 diabetes mellitus (T2DM) because patients with obesity and T2DM commonly have NAFLD, and patients with NAFLD are often obese and have T2DM with insulin resistance and dyslipidemia as well as hypertriglyceridemia. Excessive accumulation of triglycerides is a hallmark of NAFLD and NAFLD is now recognized as the liver disease component of metabolic syndrome. Liver glucose and lipid metabolisms are intertwined and carbon flux can be used to generate glucose or lipids; therefore, in this review we discuss the important transcription factors and coactivators that regulate glucose and lipid metabolism.

BAG1, MGMT, FOXO1, and DNAJA1 as potential drug targets for radiosensitizing cancer cell lines

BACKGROUND AND PURPOSE

Activation of some signaling pathways can promote cell survival and have a negative impact on tumor response to radiotherapy. Here, the role of differences in expression levels of genes related to the poly(ADP-ribose) polymerase-1 (PARP-1), heat shock protein 90 (Hsp90), B-cell lymphoma 2 (Bcl-2), and phosphoinositide 3-kinase (PI3K) pathways in the survival or death of cells following X-ray exposure was investigated.

METHODS

Eight human cell cultures (MCF-7 and MDA-MB-231: breast cancers; MCF-12A: apparently normal breast; A549: lung cancer; L132: normal lung; G28, G44 and G112: glial cancers) were irradiated with X-rays. The colony-forming and real-time PCR based on a custom human pathway RT² Profiler PCR Array assays were used to evaluate cell survival and gene expression, respectively.

RESULTS

The surviving fractions at 2 Gy for the cell lines, in order of increasing radioresistance, were found to be as follows: MCF-7 (0.200 ± 0.011), G44 (0.277 ± 0.065), L132 (0.367 ± 0.023), MDA-MB-231 (0.391 ± 0.057), G112 (0.397 ± 0.113), A549 (0.490 ± 0.048), MCF-12A (0.526 ± 0.004), and G28 (0.633 ± 0.094). The rank order of radioresistance at 6 Gy was: MCF-7 < L132 < G44 < MDA-MB-231 < A549 < G28 < G112 < MCF-12A. PCR array data analysis revealed that several genes were differentially expressed between irradiated and unirradiated cell cultures. The following genes, with fold changes: BCL2A1 (21.91), TP53 (8743.75), RAD51 (11.66), FOX1 (65.86), TCP1 (141.32), DNAJB1 (3283.64), RAD51 (51.52), and HSPE1 (12887.29) were highly overexpressed, and BAX (-127.21), FOX1 (-81.79), PDPK1 (-1241.78), BRCA1 (-8.70), MLH1 (-12143.95), BCL2 (-18.69), CCND1 (-46475.98), and GJA1 (-2832.70) were highly underexpressed in the MDA-MB-231, MCF-7, MCF-12A, A549, L132, G28, G44, and G112 cell lines, respectively. The radioresistance in the malignant A549 and G28 cells was linked to upregulation in the apoptotic, DNA repair, PI3K, and Hsp90 pathway genes BAG1, MGMT, FOXO1, and DNAJA1, respectively, and inhibition of these genes resulted in significant radiosensitization.

CONCLUSIONS

Targeting BAG1, MGMT, FOXO1, and DNAJA1 with specific inhibitors might effectively sensitize radioresistant tumors to radiotherapy.

The FoxO1-ATGL axis alters milk lipolysis homeostasis through PI3K/AKT signaling pathway in dairy goat mammary epithelial cells

Goat milk is enriched in fatty acids which are beneficial to human health. Previous research has revealed that 98% of milk fat is composed of triglycerides. However, the mechanisms regulating milk fat composition remain unclear. Forkhead box protein O1 (FoxO1) is a crucial regulatory factor involved in lipid metabolism across various cell types. Chromatin immunoprecipitation sequencing (ChIP)-seq data) and RNA sequencing (RNA-seq) data revealed that have indicated a close association between FoxO1 was closely related to lipid metabolism during lactation in dairy goats. The objective of this study was to investigate the mechanisms by which FoxO1 regulates lipid metabolism in goat mammary epithelial cells (GMECs). FoxO1 knockdown significantly downregulated the expression of adipose triglyceride lipase (ATGL) and suppressed the activity of the ATGL promoter. Consistently, the number of lipid droplets decreased significantly in FoxO1-overexpressing cells and increased in ATGL-knockdown cells. To further verify the effect of FoxO1 on ATGL promoter activity, cells were transfected with four promoter fragments of different lengths. We found that the core region of the ATGL promoter was located between -882 bp and -524 bp, encompassing two FoxO1 binding sites (FKH1 and FKH2). Mutations in the FoxO1 binding sites significantly downregulated ATGL promoter activity in GMECs. Luciferase reporter assays demonstrated that FoxO1 overexpression markedly enhanced ATGL promoter activity. Furthermore, site-directed mutation confirmed that FKH1 and FKH2 sites were simultaneously mutated significantly attenuated the stimulatory effect of FoxO1 on ATGL promoter activities simultaneous mutation of FKH1 and FKH2 sites significantly attenuated the stimulatory effect of FoxO1 on ATGL promoter activity. ChIP assays showed that FoxO1 directly binds to the FKH2 element located in the ATGL promoter in vivo. Finally, immunofluorescence staining revealed that insulin promotes the translocation of FoxO1 from the nucleus to the cytoplasm, thereby attenuating the FoxO1-induced activation of the ATGL promoter. Collectively, these findings uncover a novel pathway where by FoxO1 may regulate lipid metabolism in GMECs specifically by modulating the transcriptional activity of ATGL.

MicroRNA-486-5p suppresses inflammatory response by targeting FOXO1 in MSU-treated macrophages

Gouty arthritis (GA) is mainly caused by the precipitation of monosodium urate (MSU) crystals in the joint. Recently, different regulatory roles of microRNAs (miRNAs) in arthritis have been widely verified. Nevertheless, the specific function of microRNA-486-5p (miR-486-5p) in GA is still unclear. GA cell models in vitro were established by the treatment of 250 μg/mL MSU crystals into THP-1 cells or J774A.1 cells. Then, the accumulation of tumor necrosis factor (TNF)-α, interleukin (IL)-8, and IL-β was estimated by ELISA. The mRNA levels of TNF-α, IL-8, and IL-β were measured through RT-qPCR. The protein level of forkhead box protein O1 (FOXO1) was tested via western blot. Furthermore, the interplay of miR-486-5p and FOXO1 was evaluated via the luciferase reporter assay. In this study, MSU treatment successfully stimulated the inflammatory response in macrophage cells. MiR-486-5p downregulation was observed in THP-1 and J774A.1 cells treated with MSU, and its upregulation markedly decreased the concentration and mRNA levels of TNF-α, IL-8, and IL-β. Furthermore, FOXO1 was demonstrated to be negatively modulated by miR-486-5p. The rescue assay indicated that overexpressing FOXO1 reversed the effects of overexpressing miR-486-5p on inflammatory cytokines. Overall, this study proves that miR-486-5p inhibits GA inflammatory response via modulating FOXO1.

Identification of significant modules and hub genes involved in hepatic encephalopathy using WGCNA

BACKGROUND

Hepatic encephalopathy (HE) is a reversible syndrome of brain dysfunction caused by advanced liver disease. Weighted gene co-expression network analysis (WGCNA) could establish a robust co-expression network to identify the hub genes and underlying biological functions. This study was aimed to explore the potential therapeutic targets in HE by WGCNA.

RESULTS

The green and brown modules were found to be significantly associated with the development of HE. Functional enrichment analyses suggested the neuroinflammation, neuroimmune, extracellular matrix (ECM), and coagulation cascade were involved in HE. CYBB and FOXO1 were calculated as hub genes, which were upregulated in the HE patients. Tamibarotene and vitamin E were suggested as possible drug candidates to alleviate HE.

CONCLUSIONS

It is the first time to analyze transcriptomic data of HE by WGCNA. Our study not only promoted the current understanding of neuroinflammation in HE, but also provided the first evidence that CYBB and FOXO1 played pivotal roles in the pathogenesis of HE, which might be potential biomarkers and therapeutic targets. Tamibarotene might be a novel drug compound against HE.

Impact of Intermittent Fasting on Metabolic Syndrome and Periodontal Disease-A Suggested Preventive Strategy to Reduce the Public Health Burden

Metabolic syndrome (MetS) prevalence continues to climb significantly worldwide in today's ad libitum society. MetS has tremendous societal and economic ramifications, making it imperative to develop effective strategies for preventing and controlling it to alleviate this growing burden. Periodontal disease and MetS are associated with several risk factors. Studies in the past have demonstrated that obesity, cardiovascular illness, and type 2 diabetes mellitus have a negative effect on the severity of the periodontal disease. Patients with metabolic syndrome have elevated serum levels of proinflammatory mediators such as tumor necrosis factor-alpha interleukin-6 and C-reactive protein. Similar inflammatory mediators, such as interleukin-6, tumor necrosis factor-alpha, and C-reactive protein, are increased in patients with severe periodontal disease. Remarkably, intermittent fasting is underpinned by scientific evidence, claiming to be the most effective non-pharmacological, potential therapeutic alternative for combating a wide range of metabolic, inflammatory, and lifestyle-related diseases. Nonetheless, an insufficient investigation has been performed to determine whether intermittent fasting has therapeutic benefits on periodontal inflammation and diseases. Here, we show the interrelationship between metabolic syndrome and periodontal disease and contextualize the beneficial impact of intermittent fasting in modulating the chronic metabolic and periodontal inflammatory response. We also anticipate that this review paves the way for further exploration of intermittent fasting as a unique research paradigm representing a cost-effective alternative strategy to conventional disease management in patients with periodontal diseases and metabolic syndrome which may serve as the foundation for an integrative vision relevant to primary, diagnostic, and therapeutic purposes.

Integrating experimental model, LC-MS/MS chemical analysis, and systems biology approach to investigate the possible antidiabetic effect and mechanisms of Matricaria aurea (Golden Chamomile) in type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) is a heterogeneous disease with numerous abnormal targets and pathways involved in insulin resistance, low-grade inflammation, oxidative stress, beta cell dysfunction, and epigenetic factors. Botanical drugs provide a large chemical space that can modify various targets simultaneously. Matricaria aurea (MA, golden chamomile) is a widely used herb in Middle Eastern communities for many ailments, including diabetes mellitus, without any scientific basis to support this tradition. For the first time, this study aimed to investigate the possible antidiabetic activity of MA in a type 2 diabetic rat model, identify chemical constituents by LC-MS/MS, and then elucidate the molecular mechanism(s) using enzyme activity assays, q-RTPCR gene expression analysis, network pharmacology analysis, and molecular docking simulation. Our results demonstrated that only the polar hydroethanolic extract of MA had remarkable antidiabetic activity. Furthermore, it improved dyslipidemia, insulin resistance status, ALT, and AST levels. LC-MS/MS analysis of MA hydroethanolic extract identified 62 compounds, including the popular chamomile flavonoids apigenin and luteolin, other flavonoids and their glycosides, coumarin derivatives, and phenolic acids. Based on pharmacokinetic screening and literature, 46 compounds were chosen for subsequent network analysis, which linked to 364 candidate T2DM targets from various databases and literature. The network analysis identified 123 hub proteins, including insulin signaling and metabolic proteins: IRS1, IRS2, PIK3R1, AKT1, AKT2, MAPK1, MAPK3, and PCK1, inflammatory proteins: TNF and IL1B, antioxidant enzymes: CAT and SOD, and others. Subsequent filtering identified 40 crucial core targets (major hubs) of MA in T2DM treatment. Functional enrichment analyses of the candidate targets revealed that MA targets were mainly involved in the inflammatory module, energy-sensing/endocrine/metabolic module, and oxidative stress module. q-RTPCR gene expression analysis showed that MA hydroethanolic extract was able to significantly upregulate PIK3R1 and downregulate IL1B, PCK1, and MIR29A. Moreover, the activity of the antioxidant hub enzymes was substantially increased. Molecular docking scores were also consistent with the networks’ predictions. Based on experimental and computational analysis, this study revealed for the first time that MA exerted antidiabetic action via simultaneous modulation of multiple targets and pathways, including inflammatory pathways, energy-sensing/endocrine/metabolic pathways, and oxidative stress pathways.

A Pre-clinical Standard Operating Procedure for Evaluating Orthobiologics in an In Vivo Rat Spinal Fusion Model

The rat animal model is a cost effective and reliable model used in spinal pre-clinical research. Complications from various surgical procedures in humans often arise that were based on these pre-clinical animal models. Therefore safe and efficacious pre-clinical animal models are needed to establish continuity into clinical trials. A Standard Operating Procedure (SOP) is a validated method that allows researchers to safely and carefully replicate previously successful surgical techniques. Thus, the aim of this study is to describe in detail the procedures involved in a common rat bilateral posterolateral intertransverse spinal fusion SOP used to test the efficacy and safety different orthobiologics using a collagen-soaked sponge as an orthobiologic carrier. Only two orthobiologics are currently FDA approved for spinal fusion surgery which include recombinant bone morphogenetic protein 2 (rhBMP-2), and I-FACTOR. While there are many additional orthobiologics currently being tested, one way to show their safety profile and gain FDA approval, is to use well established pre-clinical animal models. A preoperative, intraoperative, and postoperative surgical setup including specific anesthesia and euthanasia protocols are outlined. Furthermore, we describe different postoperative methods used to validate the spinal fusion SOP, which include μCT analysis, histopathology, biomechanical testing, and blood analysis. This SOP can help increase validity, transparency, efficacy, and reproducibly in future rat spinal fusion surgery procedures.

Forkhead box protein O1 (FoxO1) knockdown accelerates the eicosapentaenoic acid (EPA)-mediated Selenop downregulation independently of sterol regulatory element-binding protein-1c (SREBP-1c) in H4IIEC3 hepatocytes

Selenoprotein P is upregulated in type 2 diabetes, causing insulin and exercise resistance. We have previously reported that eicosapentaenoic acid (EPA) negatively regulates Selenop expression by suppressing Srebf1 in H4IIEC3 hepatocytes. However, EPA downregulated Srebf1 long before downregulating Selenop. Here, we report additional novel mechanisms for the Selenop gene regulation by EPA. EPA upregulated Foxo1 mRNA expression, which was canceled with the ERK1/2 inhibitor, but not with the PKA inhibitor. Foxo1 knockdown by siRNA initiated early suppression of Selenop, but not Srebf1, by EPA. However, EPA did not affect the nuclear translocation of the FoxO1 protein. Neither ERK1/2 nor PKA inhibitor affected FoxO1 nuclear translocation. In summary, FoxO1 knockdown accelerates the EPA-mediated Selenop downregulation independent of SREBP-1c in hepatocytes. EPA upregulates Foxo1 mRNA via the ERK1/2 pathway without altering its protein and nuclear translocation. These findings suggest redundant and conflicting transcriptional networks in the lipid-induced redox regulation.

Phytochemicals targeting NAFLD through modulating the dual function of forkhead box O1 (FOXO1) transcription factor signaling pathways

Literature evidence reveals that natural compounds are potential candidates for ameliorating obesity-associated non-alcoholic fatty liver disease (NAFLD) by targeting forkhead box O1 (FOXO1) transcription factor. FOXO1 has a dual and complex role in regulating both increase and decrease in lipid accumulation in hepatocytes and adipose tissues (AT) at different stages of NAFLD. In insulin resistance (IR), it is constitutively expressed, resulting in increased hepatic glucose output and lipid metabolism irregularity. The studies on different phytochemicals indicate that dysregulation of FOXO1 causes disturbance in cellular nutrients homeostasis, and the natural entities have an enduring impact on the mitigation of these abnormalities. The current review communicates and evaluates certain phytochemicals through different search engines, targeting FOXO1 and its downstream cellular pathways to find lead compounds as potential therapeutic agents for treating NAFLD and related metabolic disorders. The findings of this review confirm that polyphenols, flavonoids, alkaloids, terpenoids, and anthocyanins are capable of modulating FOXO1 and associated signaling pathways, and they are potential therapeutic agents for NAFLD and related complications. HIGHLIGHTS: • FOXO1 has the potential to be targeted by novel drugs from natural sources for the treatment of NAFLD and obesity. • FOXO1 regulates cellular autophagy, inflammation, oxidative stress, and lipogenesis through alternative mechanisms. • Phytochemicals treat NAFLD by acting on FOXO1 or SREBP1c and PPARγ transcription factor signaling pathways.

Identification of the Core Promoter and Variants Regulating Chicken CCKAR Expression

Decreased expression of chicken cholecystokinin A receptor (CCKAR) attenuates satiety, which contributes to increased food intake and growth for modern broilers. The study aims to define the core promoter of CCKAR, and to identify variants associated with expression activity. A 21 kb region around the CCKAR was re-sequenced to detect sequence variants. A series of 5'-deleted promoter plasmids were constructed to define the core promoter of CCKAR. The effects of sequence variants located in promoter (PSNP) and conserved (CSNP) regions on promoter activity were analyzed by comparing luciferase activity between haplotypes. A total of 182 variants were found in the 21 kb region. There were no large structural variants around CCKAR. pNL-328/+183, the one with the shortest insertion, showed the highest activity among the six promoter constructs, implying that the key cis elements regulating CCKAR expression are mainly distributed 328 bp upstream. We detected significant activity differences between high- and low-growth associated haplotypes in four of the six promoter constructs. The high-growth haplotypes of constructs pNL-1646/+183, pNL-799/+183 and pNL-528/+183 showed lower activities than the low-growth haplotypes, which is consistent with decreased expression of CCKAR in high-growth chickens. Lower expression of the high-growth allele was also detected for the CSNP5-containing construct. The data suggest that the core promoter of CCKAR is located the 328 bp region upstream from the transcription start site. Lower expression activities shown by the high-growth haplotypes in the reporter assay suggest that CSNP5 and variants located between 328 bp and 1646 bp upstream form a promising molecular basis for decreased expression of CCKAR and increased growth in chickens.

Glucocorticoids induce osteonecrosis of the femoral head in rats via PI3K/AKT/FOXO1 signaling pathway

Background

Steroid-induced osteonecrosis of the femoral head (SONFH) is a disorder that causes severe disability in patients and has a high incidence worldwide. Although glucocorticoid (GC)-induced apoptosis of osteoblasts is an important cytological basis of SONFH, the detailed mechanism underlying SONFH pathogenesis remains elusive. PI3K/AKT signaling pathway was reported to involve in cell survival and apoptosis.

Objective

We explored the role of PI3K/AKT/FOXO1 signaling pathway and its downstream targets during glucocorticoid -induced osteonecrosis of the femoral head.

Methods

We obtained gene expression profile of osteoblasts subjected to dexamethasone (Dex) treatment from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were screened out and functional enrichment analysis were conducted by bioinformatics analysis. In vitro, we analyzed Dex-induced apoptosis in MC3T3-E1 cells and explored the role of PI3K/AKT/FOXO1 signaling pathway in this phenomenon by employing siRNA-FOXO1 and IGF-1(PI3K/AKT agonist). Finally, we verified our results in a rat model of SONFH.

Results

In Dex-treated osteoblasts, DEGs were mainly enriched in the FOXO signaling pathway. Dex inhibited MC3T3-E1 cell viability in a dose-dependent effect and induced apoptosis by increasing the expression levels of FOXO1, Bax, cleaved-Caspase-3, and cleaved-Caspase-9, while reducing the expression of Bcl-2. Notably, these results were reversed by siRNA-FOXO1 treatment. Dex inhibited PI3K/AKT signaling pathway, upregulated FOXO1 expression and increased FOXO1 nuclear translocation, which were reversed by IGF-1. Compared to normal rats, the femoral head of SONFH showed increased expression of FOXO1, increased number of apoptotic cells, and empty osteocytic lacunas, as well as decreased bone tissue content and femoral head integrity. Significantly, the effects of GC-induced SONFH were alleviated following IGF-1 treatment.

Conclusion

Dex induces osteoblast apoptosis via the PI3K/AKT/FOXO1 signaling pathway. Our research offers new insights into the underlying molecular mechanisms of glucocorticoid-induced osteonecrosis in SONFH and proposes FOXO1 as a therapeutic target for this disease.

DEAD-box helicase 56 functions as an oncogene promote cell proliferation and invasion in gastric cancer via the FOXO1/p21 Cip1/c-Myc signaling pathway

DEAD-box helicase (DDX) family exerts a critical effect on cancer initiation and progression through alternative splicing, transcription and ribosome biogenesis. Increasing evidence has demonstrated that DEAD-box helicase 56 (DDX56) is over-expressed in several cancers, which plays an oncogenic role. Till the present, the impact of DDX56 on gastric cancer (GC) remains unclear. We conducted high-throughput sequencing (RNA-seq) to demonstrate aberrant DDX56 levels within 10 GC and matched non-carcinoma tissue samples. DDX56 levels were detected through qRT-PCR, western blotting (WB) and immunochemical staining in GC patients. We conducted gain- and loss-of-function studies to examine DDX56's biological role in GC development. In vitro, we carried out 5‑Ethynyl‑2‑deoxyuridine (EdU), scratch, Transwell, and flow cytometry (FCM) assays for detecting GC cell growth, invasion, migration and apoptosis. Additionally, gene set enrichment analysis (GSEA), WB assay, and Encyclopedia of RNA Interactomes (ENCORI) were carried out for analyzing DDX56-regulated downstream genes and signaling pathways. In vivo, tumor xenograft experiment was performed for investigating how DDX56 affected GC development within BALB/c nude mice. Functionally, DDX56 knockdown arrested cell cycle at G1 phase, invasion and migration of AGS and MKN28 cells, and enhanced their apoptosis. Ectopic DDX56 expression enhanced the cell growth, migration and invasion, and inhibited apoptosis. Knockdown of DDX56 suppressed GC growth in the tumor models of BALB/c nude mice. Mechanistically, DDX56 post-transcriptionally suppressed FOXO1/p21 Cip1 protein expression, which could activate its downstream cyclin E1/CDK2/c-Myc signaling pathways. This sheds lights on the GC pathogenic mechanism and offers a potential anti-cancer therapeutic target.

FoxO1 silencing facilitates neurological function recovery in intracerebral hemorrhage mice via the lncRNA GAS5/miR-378a-5p/Hspa5 axis

OBJECTIVE

Intracerebral hemorrhage (ICH) is the most devastating stroke subtype. Transcription factor Forkhead box O1 (FoxO1) is extensively implicated in cerebral injury. This study investigated the mechanism of FoxO1 in neurological function recovery in ICH mice.

METHODS

A murine model of ICH was established. The modified neurological severity score (mNSS), forelimb placement test, and corner turn test were adopted to evaluate the neurological function of mice. The brain water content was measured and the pathological changes of cerebral tissues were observed. The levels of IL-1β, IL-6, and TNF-α were determined. The expressions of FoxO1, lncRNA GAS5, miR-378a-5p, and heat shock 70 kDa protein 5 (Hspa5) in mouse cerebral tissues were examined. The binding relationships among FoxO1, lncRNA GAS5, miR-378a-5p, and Hspa5 were validated. Functional rescue experiments were designed to verify the role of lncRNA GAS5/miR-378a-5p/Hspa5 axis in neurological function recovery in ICH mice.

RESULTS

FoxO1 was highly expressed in cerebral tissues of ICH mice. FoxO1 silencing facilitated neurological function recovery in ICH mice, evidenced by decreased mNSS, improved forelimb placement rate, reduced turning defects, declined brain water content, relieved edema, intracellular vacuoles, and inflammatory cell infiltration, and reduced IL-1β, IL-6, and TNF-α levels. FoxO1 enhanced lncRNA GAS5 expression by binding to its promoter. LncRNA GAS5 facilitated Hspa5 transcription by sponging miR-378a-5p. Intervention of lncRNA GAS5/miR-378a-5p/Hspa5 axis reversed the promoting effect of FoxO1 silencing on the neurological function recovery in ICH mice.

CONCLUSION

FoxO1 silencing facilitated neurological function recovery in ICH mice via the lncRNA GAS5/miR-378a-5p/Hspa5 axis.

A Motif-Based Network Analysis of Regulatory Patterns in Doxorubicin Effects on Treating Breast Cancer, a Systems Biology Study

Background

Breast cancer is the most common malignancy worldwide. Doxorubicin is an anthracycline used to treat breast cancer as the first treatment choice. Nevertheless, the molecular mechanisms underlying the response to Doxorubicin and its side effects are not comprehensively understood so far. We used systems biology and bioinformatics methods to identify essential genes and molecular mechanisms behind the body response to Doxorubicin and its side effects in breast cancer patients.

Methods

Omics data were extracted and analyzed to construct the protein-protein interaction and gene regulatory networks. Network analysis was performed to identify hubs, bottlenecks, clusters, and regulatory motifs to evaluate crucial genes and molecular mechanisms behind the body response to Doxorubicin and its side effects.

Results

Analyzing the constructed PPI and gene-TF-miRNA regulatory network showed that MCM3, MCM10, and TP53 are key hub-bottlenecks and seed proteins. Enrichment analysis also revealed cell cycle, TP53 signaling, Forkhead box O (FoxO) signaling, and viral carcinogenesis as essential pathways in response to this drug. Besides, SNARE interactions in vesicular transport and neurotrophin signaling were identified as pathways related to the side effects of Doxorubicin. The apoptosis induction, DNA repair, invasion inhibition, metastasis, and DNA replication are suggested as critical molecular mechanisms underlying Doxorubicin anti-cancer effect. SNARE interactions in vesicular transport and neurotrophin signaling and FoxO signaling pathways in glucose metabolism are probably the mechanisms responsible for side effects of Doxorubicin.

Conclusion

Following our model validation using the existing experimental data, we recommend our other newly predicted biomarkers and pathways as possible molecular mechanisms and side effects underlying the response to Doxorubicin in breast cancer requiring further investigations.

Melatonin inhibits autophagy in TM3 cells via AKT/FOXO1 pathway

BACKGROUND

Melatonin can regulate apoptosis and autophagy of mouse Leydig cells, but its specific mechanism is still unclear.

METHODS

In this study, we used the TM3 cell line as the research object, and used H2O2 to induce autophagy. After adding 10 ng/ml melatonin, we used qRT-PCR and western-blot to detect autophagy-related gene and protein expression, and flow cytometry to detect cellular ROS level.

RESULTS

The results showed that melatonin can significantly inhibit the occurrence of autophagy, accompanied by a significant decrease in the expression of Becn1, LC3, and FOXO1 (P < 0.05), a significant increase in the expression of p62 and pAKT (P < 0.05), and a significant decrease in ROS level (P < 0.05). After added the inhibitor of AKT perifosine, the effect of melatonin on inhibiting autophagy was reversed. On this basis, we used small RNA interference technology to knock down the expression of FOXO1, and found that there was no significant change of the expression of genes and proteins related to autophagy and ROS level.

CONCLUSIONS

In summary, melatonin can inhibit H2O2-induced autophagy in TM3 cells through the AKT/FOXO1 pathway.