Glycogen Synthase Kinase Research Articles

H2 protects H9c2 cells from hypoxia/reoxygenation injury by inhibiting the Wnt/CX3CR1 signaling pathway.

Myocardial ischemia-reperfusion injury is a severe cardiovascular disease, and its treatment and prevention are crucial for improving patient prognosis and reducing the economic burden. This study aimed to explore the impact of hydrogen (H2) on hypoxia/reoxygenation (H/R) injury in H9c2 cells (derived from rat embryonic heart tissue) induced by hydrogen peroxide (H2O2) and to elucidate its underlying mechanism. An H/R injury model was established in H9c2 cells via exposure to 15 μM H2O2 for 3 hours, followed by incubation in a 5% CO2 atmosphere at 37°C for 24 hours. Then, the cells were treated with H2 (50%) for 6, 12 or 24 hours. The results demonstrated that H9c2 cells exposed to H2O2 and subjected to H/R injury presented a marked decrease in the cell survival rate, accompanied by severe morphological alterations, such as curling and wrinkling, and elevated lactate dehydrogenase levels. Notably, H2 mitigated H/R injury induced by H2O2 in a time-dependent manner, improving the morphological damage observed in H9c2 cells and decreasing lactate dehydrogenase levels. Compared with the model group, treatment with H2 increased the activities of antioxidant enzymes, including catalase, superoxide dismutase, and glutathione peroxidase, while concurrently reducing the level of malondialdehyde, an indicator of cellular damage. Furthermore, H2 treatment downregulated the expression of inflammatory cytokines and inflammatory-related factors, specifically interleukin-6, high-mobility group box 1, tumor necrosis factor-alpha, and Toll-like receptor 4, in H9c2 cells post-H/R injury. Furthermore, H2 treatment resulted in a marked decrease in the expression levels of proteins associated with the Wnt/C-X3-C-motif receptor 1 signaling pathway, such as β-catenin, glycogen synthase kinase-3 beta, adenomatous polyposis coli, and Wnt and C-X3-C-motif receptor 1. This observation suggests a potential mechanism for its protective effects against H/R injury. Therefore, H2 exerts a protective effect against H/R injury in H9c2 cells induced by H2O2, potentially by inhibiting the activated Wnt/C-X3-C-motif receptor 1 signaling pathway. This inhibition, in turn, prevents the generation of oxidative stress, inflammatory cytokines, and inflammation-associated factors.

Swertiamarin and sweroside are potential inhibitors of COVID-19 based on the silico analysis

The severity of the respiratory disease caused by the severe acute respiratory syndrome coronavirus 2 has escalated rapidly in recent years, posing a significant threat to global health. Sweroside and swertiamarin are bioactive iridoid glycosides extracted mainly from Swertia davidii Franch. It remains unclear how Swertia davidii Franch. Specifically affects COVID-19 and its underlying mechanisms. We first employed network pharmacology and molecular docking techniques to investigate how sweroside and swertiamarin affect COVID-19 in order to explore its potential mechanism. We found that 35 potential target genes can be used for the treatment of COVID-19, with androgen receptor (AR), HSP90AA1, RAC-alpha serine/threonine–protein kinase, cyclin-dependent kinase 1, epidermal growth factor receptor, and glycogen synthase kinase-3 beta emerging as particularly promising candidates. Additionally, sweroside and swertiamarin demonstrated unambiguous interactions with the 3CL protease AR through molecular docking research. At the active site, sweroside and swertiamarin can bind to AR (1T65), the main protease (5R82), and 3CL protease (6M2N), showing therapeutic potential.

A NETWORK PHARMACOLOGY-BASED DRUG REPURPOSING STUDY OF LEVETIRACETAM UNCOVERS ITS INTERACTION WITH MULTI-DRUG TARGETS IN PARKINSON'S DISEASE

Objective: The current study utilized network pharmacology to examine how Levetiracetam interacts with specific drug targets associated with Parkinson's Disease (PD) treatment. Methods: We used information from Kyoto Encyclopedia of Genes and Genome (KEGG) studies and Protein-Protein Interaction (PPI) pathway analysis to create a network that depicts the relationships between Levetiracetam and PD targets. Further investigation involved PPI analysis, molecular docking, and Molecular Dynamics (MD) simulation studies, ultimately pinpointing five protein targets. Their participation in pathways such as Ribonucleic acid Polymerase II-specific Deoxyribonucleic acid binding Transcription Factor Binding (Gene Ontology [GO]:0061629), Axon (GO: 0030424), and Excitatory Postsynaptic Potential was emphasized by GO and KEGG pathway enrichment. Additionally, Dopamine Receptor D2 (DRD2), Solute Carrier Family 6 Member 3 (SLC6A3), Glycogen Synthase Kinase 3 Beta (GSK3B), Poly (ADP-ribose) Polymerase 1 (PARP1) and Myeloperoxidase (MPO) were identified as protein targets through PPI and molecular docking analysis. Results: The results of molecular docking showed that protein targets, SLC6A3, have highest binding affinity with Levetiracetam. The MD Simulation result of Levetiracetam-SLC6A3 docked complex represented the complex to be quite stable with few conformational changes in the SLC6A3 structure. DRD2, SLC6A3, GSK3B, PARP1, MPO were recognized as the likely protein targets of Levetiracetam for treating PD. SLC6A3 was considered as a target of Levetiracetam in PD. Conclusion: Our study revealed the mechanism of Levetiracetam in the treatment of PD and can contribute to more effective treatment for the same. By identifying key protein targets, this research lays the groundwork for future studies that could further explore Levetiracetam’s efficacy.

In Silico and In Vitro Evaluation of Quinoline Derivatives as Potential Inhibitors of AChE, BACE1, and GSK3β for Neurodegenerative Diseases Treatment.

Neurodegenerative diseases are characterized by the structural and functional loss of neurons, affecting populations worldwide. Enzymes like acetylcholinesterase (AChE), beta-site APP cleaving enzyme-1 (BACE1), and glycogen synthase kinase 3-beta (GSK3β), contribute to their development. This study explores in silico and in vitro assays of quinoline analogues as potential inhibitors of these enzymes. In silico analyses highlighted derivative SQ6 as the most potent inhibitor for all proteins. In vitro assays confirmed that the quinoline derivatives had a modulating action on the three targets. SQ6 showed a significant AChE inhibition of 94.6%. Regarding the inhibition of GSK3β and BACE1, derivatives SQ6-SQ9, with the quinoline linked to the sulfonamide nitrogen, showed inhibition values above 40%. SQ7 and SQ9 were not considered cytotoxic for cell proliferation in human glioblastoma, and SQ6 did not show cytotoxicity at 7.8 and 3.9 µg mL-1. In murine fibroblasts, SQ6 presented a result similar to that observed for cell proliferation in human glioblastoma, while SQ7 and SQ9 were non-cytotoxic below 62.5 µg mL-1. These findings underscore compound SQ6 as the first potential multitarget enzyme inhibitor for treating neurodegenerative diseases.

Computer-aided Drug Discovery of Epigenetic Modulators in Dual-target Therapy of Multifactorial Diseases.

Numerous studies suggest that common genetic and epigenetic factors such as p53, histone deacetylase (HDAC), brain-derived neurotrophic factor (BDNF), the (Ataxia Telangiectasia mutated) ATM gene, cyclin-dependent kinase 5 (CDK5), glycogen synthase kinase 3 (GSK3) and altered expression of microRNA (miRNA) play a crucial role in cancer and neurodegeneration. As there is growing evidence that epigenetic aberrations in cancer and neurological diseases lead to complex pathophysiological changes, the simultaneous targeting of epigenetic and other related pathways by dual-target inhibitors may contribute to the discovery of more effective and personalized therapeutic options. Computer-Aided Drug Design (CADD) provides comprehensive bioinformatic, chemoinformatic, and chemometric approaches for the design of novel chemotypes of epigenetic dual-target inhibitors, enabling efficient discovery of new drug candidates for innovative treatments of these multifactorial diseases. The detailed anticancer mechanisms by which the epigenetic dual-target inhibitors alter metastatic and tumorigenic properties, influence the tumor microenvironment, or regulate the immune response are also presented and discussed in the review. To improve our understanding of the pathogenesis of cancer and neurodegeneration, this review discusses novel therapeutic agents targeting different molecular mechanisms involved in these multifactorial diseases.

Aloe Emodin Alleviates Radiation-Induced Heart Disease via Blocking P4HB Lactylation and Mitigating Kynurenine Metabolic Disruption.

Aloe emodin is an anthraquinone of traditional Chinese medicine monomer, which plays a protective action in cardiovascular diseases. However, the regulatory mechanisms of aloe emodin in the protection of radiation-induced heart damage (RIHD) are unclear. As a novel post-translational modification, lactylation is considered as a critical mediator in inflammatory cascade and cardiac injury. Here, using a cross of differential omics and 4D label-free lactylation omics, protein disulfide-isomerase (P4HB) is identified as a novel target for lactylation, and aloe emodin inhibits the binding of lactate to the K311 site of P4HB. Aloe emodin stabilizes kynurenine metabolism through inhibition of aspartate aminotransferase (GOT2) accumulation on damaged mitochondria. Mechanistically, aloe emodin inhibits phosphorylated glycogen synthase kinase 3B (p-GSK3B) transcription in the nucleus to repress the interaction of prostaglandin G/H synthase 2 (PTGS2) with SH3 domain of SH3 domain-containing GRB2-like protein B1 (SH3GLB1), thereby disrupting the functions of mitochondrial complexes and reducing SH3GLB1-mediated mitoROS accumulation, eventually suppressing calcium-binding and coiled-coil domain-containing protein 2 (NDP52)-induced mitophagy. This study unveils the regulatory role of aloe emodin in RIHD alleviation through PTGS2/SH3GLB1/NDP52 axis, indicates aloe emodin stabilizes GOT2-mediated kynurenine metabolism through P4HB lactylation. Collectively, this study provides novel insights into the regulatory mechanisms underlying the protective role of aloe emodin in cardiac injury, and opens new avenues for therapeutic strategies of aloe emodin in preventing RIHD by regulating lactylation.

The novel secretome ST266 activates Akt and protects against oxidative stress-mediated injury in human RPE and Müller cells

Oxidative stress-mediated retinal pigment epithelial (RPE) cell damage is associated with age-related macular degeneration (AMD). ST266 is the biological secretome produced by a novel population of amnion-derived multipotent progenitor cells. Herein, we investigated the effect of ST266 on RPE cell injury induced by hydroquinone (HQ), a cigarette smoke related oxidant, hydrogen peroxide (H2O2) and all-trans retinal (atRal), a pro-oxidant component of the retinoid cycle. We additionally investigated its effect on Müller cell injury induced by H2O2.Cultured human RPE cells were pre-treated for 1 hour in the presence or absence of MK-2206, a protein kinase B (Akt) inhibitor, then treated with varying concentrations of HQ, H2O2, or atRal for 1.5 hours. Cultured human Müller cells (MIO-M1) were pre-treated for 1 hour in the presence or absence of MK-2206, then treated with varying concentrations of H2O2 for 1.5 hours. Media were then replaced with STM100 (control media into which the ST266 secretome proteins were collected) or ST266 at various times. Cell viability was determined with WST-1 reagent. Mitochondrial membrane potential (Δψm) was quantified by a fluorescence plate reader. The protein phosphorylation levels of Akt, glycogen synthase kinase 3 beta (GSK-3β), and p70 ribosomal S6 kinase (p70S6K) were measured by Western blot.ST266 significantly improved RPE and MIO-M1 cell viability that was reduced by oxidant exposure and improved oxidant-disrupted Δψm. In both cell types, ST266 induced phosphorylation of Akt, GSK-3β, and p70S6K. MK-2206 significantly eliminated ST266-mediated protein phosphorylation of Akt, GSK-3β, and p70S6K and abolished the ST266-protective effect on cell viability. In conclusion, ST266 activates Akt, protects against oxidative stress-mediated cell injury in an Akt-dependent manner, and improves Δψm, suggesting a potential role for ST266 therapy in treating retinal diseases such as AMD.

Inhibition of mitochondrial OMA1 ameliorates osteosarcoma tumorigenesis

OMA1 is an ATP-independent zinc metalloprotease essential for maintaining mitochondrial homeostasis and plays a vital role in tumorigenesis. Depending on the type of cancer, a decrease in OMA1 expression has been linked to a varying prognosis for patients. The role of OMA1 in human osteosarcoma (OS), one of the most prevalent malignant bone tumors, remains elusive. Here, we observed elevated OMA1 expression in OS tumor tissues from four patients with advanced OS. Knockout of OMA1 in OS cells significantly reduces OS tumor weight and size, and lung metastatic nodules in BALB/c nude mice. Immunohistochemistry analysis showed a significant decrease in Ki67 and an increase in Cleaved-caspase 3 in OMA1 knockout tumor samples. Mechanistically, we found that OMA1 deficiency increases the levels of PINK1 and Parkin and consequently induces excessive mitophagy, leading to increased apoptosis and reduced cell proliferation and invasion in OS cells. Specifically, OMA1 deficiency reduces the amount of cytosolic p53 and p53-associated cytosolic Parkin but increases mitochondrial p53, which may lead to enhanced apoptosis. Regarding the effect on cell proliferation and invasion, loss of OMA1 reduces mitochondrial ROS levels and increases cytosolic glycogen synthase kinase 3β (GSK3β) levels, thereby increasing interaction between GSK3β and β-catenin and then reducing cytosolic and nuclear β-catenin. This contributes to reduced cell proliferation and migration in OMA1-deficient cells. Moreover, we found that ciclopirox (CPX), an antifungal drug, induces OMA1 self-cleavage and L-OMA1 degradation in cultured OS cells. CPX also reduces tumor development of control OS cells but not OMA1-deficient OS cells in mice. These findings strongly support the important role of OMA1 in OS tumorigenesis and suggest that OMA1 may be a valuable prognostic marker and a promising therapeutic target for OS.

SARS-CoV-2 propagation to the TPH2-positive neurons in the ventral tegmental area induces cell death via GSK3β-dependent accumulation of phosphorylated tau.

COVID-19, an infectious disease caused by SARS-CoV-2, was declared a pandemic by the WHO in 2020. Psychiatric symptoms including sleep disturbance, memory impairment, and depression are associated with SARS-CoV-2 infection. These symptoms are causes long-term mental and physical distress in recovering patients; however, the underlying mechanism is unclear. In this study, we determined the effects of SARS-CoV-2 infection on brain tissue using k18hACE2 mice. Using brain tissue from 18hACE2 mice infected with SARS-CoV-2 through intranasal administration, SARS-CoV-2 spike protein and RNA were analyzed by immunohistochemical staining and in-situ hybridization. Immunohistochemical analysis revealed that Tryptophan hydroxylase 2 (TPH2)-positive cells and SARS-CoV-2 spike protein were co-localized in the ventral tegmental area of SARS-CoV-2-infected mice. We observed decreased TPH2 expression and increased accumulation of phosphorylated tau protein and Phospho-Histone H2A.X (γH2AX) expression in the ventral tegmental region. In addition, activation of glycogen synthase kinase 3β (GSK3β) was induced by SARS-CoV-2 infection. Overall, our results suggest that SARS-CoV-2 infection of TPH2-positive cells in the ventral tegmental area induces neuronal cell death through increased accumulation of phosphorylated tau. Attenuation of the GSK3β pathway and decreased serotonin synthesis through suppression of TPH2 expression may contribute to the development of neurological symptoms.

Elraglusib induces cytotoxicity via direct microtubule destabilization independently of GSK3 inhibition.

Elraglusib (9-ING-41) is an ATP-competitive inhibitor of glycogen synthase kinase-3 (GSK3) with pre-clinical studies demonstrating broad activity against many tumour types. Promising early-phase clinical trial data led to FDA orphan drug status, and a randomized phase 2 study in combination with cytotoxic chemotherapy in pancreatic cancer has recently completed its recruitment. Similarly, single-agent responses in adult T-cell leukaemia/lymphoma and melanoma, and combination treatment data in several other tumour types have been encouraging. The elraglusib mechanism of action is unknown, but it is unlikely to act through GSK3 inhibition because cytotoxicity is observed below the IC50 for GSK3 and other small molecule GSK3 inhibitors do not produce cytotoxic effects, at least in lymphoma cells. We show here that elraglusib perturbs chromosomal alignment to cause a mitotic arrest in multiple tumour lines. This arrest is caused by direct microtubule depolymerization, which prevents the attachment of kinetochores to microtubules. At clinically relevant doses, these mitotically arrested cells eventually undergo mitotic slippage, leading to gross chromosome missegregation, DNA damage and apoptosis. These effects explain the cytotoxicity of elraglusib because temporarily pausing cell cycle progression with the CDK4/6 inhibitor palbociclib abolishes any drug-induced genotoxicity and apoptosis. In summary, elraglusib acts as a direct microtubule destabilizer both in vitro and across multiple cancer types, resulting in mitotic arrest, DNA damage and apoptosis. These effects likely account for its broad pan-cancer activity, which does not rely upon GSK3 inhibition as they are not replicated by other GSK3 inhibitors.

Protein kinases as therapeutic targets for Alzheimer’s disease: a brief review

Alzheimer’s disease (AD) is a progressive and incurable neurodegenerative disorder, with an unknown etiology and a multifactorial pathophysiology characterized by protein misfolding, neuroinflammation, and neuronal loss. There are three well-discussed main hypotheses for the pathophysiology of AD, which are related to i) the accumulation of amyloid β (Aβ) protein aggregates in the extracellular space, ii) deposition of hyperphosphorylated tau fragments as neurofibrillary tangles, and iii) dysregulation of hemostasis of some neurotransmitters involved in the disease, such as acetylcholine (ACh) and glutamate. The association of all these factors is responsible for installing oxidative stress and neuroinflammation, which contribute to progressive neuronal death in specific brain regions. More recently, other remarkable pathological characteristics have been described, involving changes in all levels of cellular components, especially in the action and function of protein kinases. These enzymes are crucial for cellular regulation since they play a pivotal role in the phosphorylation of protein substrates by transferring a phosphate group from the ATP molecule to threonine, serine, or tyrosine residues. In more recent studies, some kinases have been especially reported by their role in inflammatory and oxidative processes associated to AD, such as cAMP-dependent protein kinase A (PKA), cyclin-dependent protein kinase 5 (CDK5), glycogen synthase kinase 3β (GSK-3β), and the microtubule affinity regulatory kinases (MARKs). Under homeostatic conditions, protein kinases act as cellular signals, directing physiological responses, but in AD pathogenesis, these enzymes have an exacerbated activity in the brain, justifying the need for a better comprehension of their function and role, and how new kinase inhibitors could lead to innovative drugs. In this context, this brief review aimed to compile the literature data related to the most recent efforts and strategies in Medicinal Chemistry in the discovery of new kinase inhibitors, opening new ways to AD therapeutics.

Discovery of Two GSK3β Inhibitors from Sophora flavescens Ait. using Structure-based Virtual Screening and Bioactivity Evaluation.

Kushen (Sophora flavescens Ait.) has a long history of medicinal use in China due to its medicinal values, such as antibacterial, antiviral, and anti-inflammatory. Rapid discovery of the components and the medicinal effects exerted by Kushen will help elucidate the science of Kushen in curing diseases. GSK3β (glycogen synthase kinase-3 beta) is a protein kinase with a wide range of physiological functions, such as antibacterial, antiviral, and anti-inflammatory. The discovery of inhibitors targeting GSK3β from Kushen was not only helpful for the rapid discovery of the components responsible for the efficacy of Kushen but also important for the development of novel drugs. In this study, the chemical composition of Kushen was extracted from the TMSCP database. Molecular docking, GSK3β enzyme assay, and molecular dynamics simulations were used to discover the GSK3β inhibitors from the chemical composition of Kushen. A total of 113 chemical compositions of Kushen were extracted from the TMSCP database. Molecular docking indicated that 15 chemical compositions of Kushen scored better than -8 kcal/mol against GSK3β. GSK3β enzyme assay demonstrated several inhibitory activities of kushenol I and kushenol F with IC50 values of 7.53 ± 2.55 μM and 4.96 ± 1.29 μM, respectively. Molecular dynamics simulations were used to reveal the interactions of kushenol I and kushenol F with GSK3β from structural and energetic perspectives. Kushenol I and kushenol F could be the material basis for the antibacterial, antiviral, and anti-inflammatory properties of Kushen.

Prolonged treatment of compactin, atorvastatin, lovastatin or simvastatin decreased glucose consumption and expressions of proteins for glucose metabolism and insulin signaling in L6 skeletal muscle cells

Statins inhibit mevalonate synthesis and successfully lower plasma cholesterol levels and decrease the risk of cardiovascular diseases in humans, but also lead to myalgia in some patients. We hypothesize that statins may modulate glucose metabolism and insulin signaling in the skeletal muscle cells during and after differentiation, and in turn lead to side effects. Here, differentiating and differentiated L6 muscle cells were treated with 1 μM of different class of statins (compactin, pravastatin, atorvastatin, lovastatin and simvastatin) with or without insulin or mevalonate for extended periods of time. The glucose consumption and expression levels of proteins for glucose metabolism and insulin receptor (IR)/Akt signaling were determined. The prolonged statin treatments (except pravastatin) decreased glucose consumption in L6 skeletal muscle cells. In differentiating L6 cells, compactin, lovastatin or simvastatin decreased the expression levels of proteins involved in glucose metabolism and insulin signaling, including glucose transporter 4 (GLUT4), pyruvate dehydrogenase (PDH), glycogen synthase (GS), glycogen synthase kinase 3β (GSK3β) and insulin receptor β subunit (IRβ). In differentiated L6 cells, long-term treatment of compactin or simvastatin also decreased levels of proteins in glucose metabolism and IR/Akt signaling, including GLUT4, GSK3β, IRβ and PI3K p110α. Insulin treatment restored statin-mediated impairments in L6 cells. The insulin-mediated phosphorylation of Akt Ser473 was attenuated in differentiating and differentiated L6 cells in the presence of atorvastatin (differentiated only), compactin, lovastatin or simvastatin. In addition, mevalonate supplementation reversed the statin-mediated impairments in differentiated and differentiating L6 cells. Statin affected glucose usage and insulin signaling by inhibiting mevalonate synthesis in L6 cells. Our results provides a possible mechanism of adverse effects of statins in skeletal muscle and calls for cautious use of the medication in patients with impaired insulin sensitivity and glucose metabolism.

Crocin has a greater therapeutic role in the restoration of behavioral impairments caused by maternal social isolation in adolescent than in adult offspring probably through GSK-3beta downregulation

Parental stress drastically impairs cognitive and behavioral functions of the offspring. Social isolation, as one of the most stressful conditions for social animals including rats induces a wide range of destructive effects on behavioral functions. On the other hand, Crocin (active component of Crocus sativa) induces pro-cognitive and neuroprotective effects. In the present study, we aimed to investigate the effects of prolonged maternal social isolation (pre-gestational) and crocin treatment on cognitive and behavioral functions in both adolescent and adult offspring. Female adult rats (mothers) were socially isolated from PND 30 to PND 80 (50 days). The treatment was performed by intraperitoneal injections of crocin (10, 30, and 50 mg/kg) during PND 39–45 or PND 59–65 (7 consecutive days), in the rat offspring. Behavioral assessments were done when the offspring were on PND 45 (adolescent) or PND 65 (adult). The expression level of Glycogen synthase kinase-3 beta (GSK-3beta) in the hippocampus was measured using real-time PCR. The results showed maternal social isolation decreased locomotion and impaired memory in adolescents, and increased anxiety- and depressive-like behaviors and GSK-3beta level, and decreased pain threshold in both adolescents and adults. Crocin (30 and 50 mg/kg) restored or attenuated the effect of maternal social isolation on behavioral functions and GSK-3beta in adolescents and adults, with more effect in adolescents. In conclusion, we showed that crocin treatment can restore the destructive effects of maternal social isolation stress in the offspring, with stronger therapeutic effects in adolescents. Also, GSK-3beta downregulation may underlie the beneficial effects of crocin.

Apigenin's Influence on Inflammatory and Epigenetic Responses in Rat Lungs After Radiotherapy.

The lung is a moderately radio-sensitive organ. When cells are damaged due to accidental radiation exposure or treatment, they release molecules that lead to the recruitment of immune cells, accumulating inflammatory cytokines at the site of damage. Apigenin (Api) is a natural flavonoid known for its anti-inflammatory properties. In this study, we investigated the radioprotective properties of Api in the lung. Thirty-six Wistar rats were randomly assigned to nine groups: control, radiation (Rad), CMC+Rad, Api10+Rad, and Api20+Rad. Api was administered with an intraperitoneal injection for 7 days, after which the rats were irradiated with 6 Gy whole-body X-ray. At 6 and 72 hours post-irradiation, the rats were euthanized, and their lung tissue was extracted. Radiation led to increased alveolar wall thickness and the infiltration of macrophages and lymphocytes. Furthermore, the expression levels of inflammatory factors such as a nuclear factor of kappa light polypeptide gene enhancer in B-cells (NF-ĸB), Glycogen synthase kinase-3 beta (GSK-3β), transforming growth factor-beta1 (TGF-β1), and epigenetic factors including DNA methyltransferase 3a (DNMT3a) and Histone deacetylase 2 (HDAC2) were elevated in the lung tissue following radiation. Meanwhile, the expression level of IκB-α decreased. However, administration of Api (at both 10&20 mg/kg) reversed the adverse effects of radiation. Api administration mitigated radiation-induced lung damage by reversing inflammatory and epigenetic changes.

Cloperastine Reduces IL-6 Expression via Akt/GSK3/Nrf2 Signaling in Monocytes/Macrophages and Ameliorates Symptoms in a Mouse Sepsis Model Induced by Lipopolysaccharide.

Cloperastine (CLP) is a drug with a central antitussive effect that is used to treat bronchitis. Therefore, we have attempted to examine the anti-inflammatory effects of CLP. CLP reduced the secretion of interleukin (IL)-6, a pro-inflammatory cytokine, from RAW264.7 monocyte/macrophage-linage cells treated with lipopolysaccharide (LPS). IL-6 is a biomarker of sepsis and has been suggested to exacerbate its symptoms. We found that the intraperitoneal administration of CLP reduced IL-6 levels in the lungs and also improved hypothermia in mice with LPS-induced sepsis. CLP ameliorated kidney pathologies such as congestion and increased the survival rate of mice administered with a lethal dose of LPS. To reveal the mechanisms underlying the anti-inflammatory function of CLP, we analysed the intracellular signaling in LPS-treated RAW264.7 cells. CLP induced the phosphorylation of protein kinase B (Akt) and glycogen synthase kinase 3 (GSK3) and also increased the amount of nuclear factor erythroid-2-related factor 2 (Nrf2) in RAW264.7 cells with/without LPS. Wortmannin, an inhibitor of phosphoinositide 3-kinase (PI3K), reduced the upregulated phosphorylation levels of Akt and GSK3 and the increased amount of Nrf2. It also halted the reduction of IL-6 secretion caused by CLP. These results suggest that CLP has an anti-inflammatory function via Akt/GSK3/Nrf2 signaling and could be a candidate drug for the treatment of inflammatory diseases, including sepsis.

Estrogen Enhances FDFT1 Expression in Theca Cells of Chicken Hierarchical Ovarian Follicles by Increasing LSD1Ser54p Level Through GSK3β Phosphorylation at 216th Tyrosine

The development of chicken ovarian follicles involves two key stages of primordial follicle recruitment and follicle selection that are tightly regulated by multiple reproductive hormones and cytokines. Our previous study revealed an estrogen-stimulated increase in the phosphorylation level of serine at position 54 of lysine demethylase 1A (LSD1Ser54p) in the theca cells of chicken hierarchical ovarian follicles (Post-TCs). In this study, we further found that the upregulation of LSD1Ser54p by estrogen was performed by glycogen synthase kinase 3 beta (GSK3β) and that GSK3β promoted LSD1Ser54p levels by directly binding to the SWIRM and AOL1 domains of LSD1. Upon estrogen stimulation, the phosphorylation level of tyrosine at position 216 of GSK3β (GSK3βTyr216p) increased, which enhanced the binding between LSD1 and GSK3β. The subsequent transcriptome sequencing on chicken Post-TCs treated with estrogen and CUT&RUN sequencing against the LSD1Ser54p protein revealed that the expression of the farnesyl-diphosphate farnesyltransferase 1 (FDFT1) gene was simultaneously upregulated by estrogen, GSK3β, and LSD1Ser54p. Moreover, the overexpression of FDFT1 further promoted cholesterol biosynthesis in chicken Post-TCs. In short, the findings of this study suggest that estrogen-induced tyrosine phosphorylation at position 216 of GSK3β can upregulate the level of LSD1Ser54p, leading to the activation of FDFT1 expression and subsequently promoting cholesterol biosynthesis in chicken Post-TCs, which may in turn enhance estrogen synthesis.

Glycogen synthase kinase 3 (GSK3) inhibition: a potential therapeutic strategy for Alzheimer's disease.

Alzheimer's disease (AD), the most common type of dementia among older adults, is a chronic neurodegenerative pathology that causes a progressive loss of cognitive functioning with a decline of rational skills. It is well known that AD is multifactorial, so there are many different pharmacological targets that can be pursued. According to estimates from the World Health Organization (WHO), 18 million individuals worldwide suffer from AD. Major initiatives to identify risk factors, enhance care giving, and conduct basic research to delay the beginning of AD were started by the USA, France, Germany, France, and various other nations. Widely recognized as a key player in the development and subsequent progression of AD pathogenesis, glycogen synthase kinase-3 (GSK-3) controls a number of crucial targets associated with neuronal degeneration. GSK-3 inhibition has been linked to reduced tau hyperphosphorylation, β-amyloid formation, and neuroprotective benefits in Alzheimer's disease. Lithium, the very first inhibitor ofGSK-3βthat was used therapeutically,has been successfully used for many years with remarkable results. A great variety of structurally varied strong GSK-3β blockers have been identified in recent years. The purpose of this thorough review is to cover the biological and structural elements of glycogen synthase kinase, as well as the medicinal chemistry aspects of GSK inhibitors that have been produced in recent years.

Fgk3, a Glycogen Synthase Kinase, Regulates Chitin Synthesis through the Carbon Catabolite Repressor FgCreA in Fusarium graminearum.

The glycogen synthase kinase-3 (GSK3) orthologs are well-conserved in eukaryotic organisms. However, their functions remain poorly characterized in filamentous fungi. In our previous study, we unveiled the function of Fgk3, the GSK3 ortholog, in glycogen metabolism in Fusarium graminearum, the causal agent of Fusarium head blight. Interestingly, the fgk3 mutant was unstable and tended to produce fast-growing suppressors, including secondary suppressors. Using whole-genome sequencing, we identified suppressor mutations in FgCHS5, FgFKS1, FgCREA, FgSSN6, FgRGR1, and FgPP2A in nine primary and four secondary suppressors. Subsequently, we validated that deletion of FgCHS5 or FgCREAΔH253 mutation partially suppressed the defects of fgk3 in vegetative growth and cell wall integrity, suggesting that Fgk3 may regulate the chitin synthesis through FgCreA-mediated transcriptional regulation in F. graminearum. Accordingly, the FGK3 deletion led to hyphal swelling with abnormal chitin deposition, and deletion of FGK3 or FgCREA caused the upregulation of the expression of chitin synthases FgCHS5 and FgCHS6. The interaction between Fgk3 and FgCreA was verified by Yeast two-hybrid and Co-Immunoprecipitation assays. More importantly, we verified that the nuclear localization and protein stability of FgCreA relies on the Fgk3 kinase, while the H253 deletion facilitated the re-localization of FgCreA to the nucleus in the fgk3 mutant background, potentially contributing to the suppression of the fgk3 mutant's defects. Intriguingly, the ΔH253 mutation of FgCreA, identified in suppressor mutant S3, is adjacent to a conserved phosphorylation site, S254, suggesting that this mutation may inhibit the S254 phosphorylation and promote the nuclear localization of FgCreA. Collectively, our findings indicate that the glycogen synthase kinase Fgk3 regulates the chitin synthesis through the carbon catabolite repressor FgCreA in F. graminearum.

Dietary Flavonoid Chrysin Functions as a Dual Modulator to Attenuate Amyloid-β and Tau Pathology in the Models of Alzheimer's Disease.

Growing evidence indicates that healthy diets are associated with a slower progression of Alzheimer's disease (AD). Flavonoids are among the most abundant natural products in diets beneficial to AD, such as the Mediterranean diet. However, the effect and mechanism of these dietary flavonoids on AD remains incompletely understood. Here, we found that a representative dietary natural flavonoid, chrysin (Chr), significantly ameliorated cognitive impairment and AD pathology in APP/PS1 mice. Furthermore, mechanistic studies showed that Chr significantly reduced the levels of amyloid-β (Aβ) and phosphorylated tau (p-tau), along with dual inhibitory activity against β-site amyloid precursor protein cleaving enzyme 1 (BACE1) and glycogen synthase kinase 3β (GSK3β). Moreover, the effect of Chr was further confirmed by EW233, a structural analog of Chr that exhibited an improved pharmacokinetic profile. To further verify the role of Chr and EW233, we utilized our previously established chimeric human cerebral organoid (chCO) model for AD, in which astrogenesis was promoted to mimic the neuron-astrocyte ratio in human brain tissue, and similar dual inhibition of Aβ and p-tau was also observed. Altogether, our study not only reveals the molecular mechanisms through which dietary flavonoids, such as Chr, mitigate AD pathology, but also suggests that identifying a specific constituent that mimics some of the benefits of these healthy diets could serve as a promising approach to discover new treatments for AD.