GSK-3β Expression Research Articles

The redox-sensitive GSK3β is a key regulator of glomerular podocyte injury in type 2 diabetic kidney disease

Emerging evidence suggests that GSK3β, a redox-sensitive transducer downstream of insulin signaling, acts as a convergent point for myriad pathways implicated in kidney injury, repair, and regeneration. However, its role in diabetic kidney disease remains controversial. In cultured glomerular podocytes, exposure to a milieu of type 2 diabetes elicited prominent signs of podocyte injury and degeneration, marked by loss of homeostatic marker proteins like synaptopodin, actin cytoskeleton disruption, oxidative stress, apoptosis, and stress-induced premature senescence, as shown by increased staining for senescence-associated β-galactosidase activity, amplified formation of γH2AX foci, and elevated expression of mediators of senescence signaling, like p21 and p16INK4A. These degenerative changes coincided with GSK3β hyperactivity, as evidenced by GSK3β overexpression and reduced inhibitory phosphorylation of GSK3β, and were averted by tideglusib, a highly-selective small molecule inhibitor of GSK3β. In agreement, post-hoc analysis of a publicly-available glomerular transcriptomics dataset from patients with type 2 diabetic nephropathy revealed that the curated diabetic nephropathy-related gene set was enriched in high GSK3β expression group. Mechanistically, GSK3β-modulated nuclear factor Nrf2 signaling is involved in diabetic podocytopathy, because GSK3β knockdown reinforced Nrf2 antioxidant response and suppressed oxidative stress, resulting in an improvement in podocyte injury and senescence. Conversely, ectopic expression of the constitutively active mutant of GSK3β impaired Nrf2 antioxidant response and augmented oxidative stress, culminating in an exacerbated diabetic podocyte injury and senescence. Moreover, IRS-1 was found to be a cognate substrate of GSK3β for phosphorylation at IRS-1S332, which negatively regulates IRS-1 activity. GSK3β hyperactivity promoted IRS-1 phosphorylation, denoting a desensitized insulin signaling. Consistently, in vivo in db/db mice with diabetic nephropathy, GSK3β was hyperactive in glomerular podocytes, associated with IRS-1 hyperphosphorylation, impaired Nrf2 response and premature senescence. Our finding suggests that GSK3β is likely a novel therapeutic target for treating type 2 diabetic glomerular injury.

Functionalized lipid nanoparticles modulate the blood-brain barrier and eliminate α-synuclein to repair dopamine neurons

The challenge in the clinical treatment of Parkinson's disease lies in the lack of disease-modifying therapies that can halt or slow down the progression. Peptide drugs, such as exenatide (Exe), with potential disease-modifying efficacy, have difficulty in crossing the blood-brain barrier (BBB) due to their large molecular weight. Herein, we fabricate multi-functionalized lipid nanoparticles (LNP) Lpc-BoSA/CSO with BBB targeting, permeability-increasing and responsive release functions. Borneol is chemically bonded with stearic acid and, as one of the components of Lpc-BoSA/CSO, is used to increase BBB permeability. Immunofluorescence results of brain tissue of 15-month-old C57BL/6 mice show that Lpc-BoSA/CSO disperses across the BBB into brain parenchyma, and the amount is 4.21 times greater than that of conventional LNP. Motor symptoms of mice in Lpc-BoSA/CSO-Exe group are significantly improved, and the content of dopamine is 1.85 times (substantia nigra compacta) and 1.49 times (striatum) that of PD mice. α-Synuclein expression and Lewy bodies deposition are reduced to 51.85% and 44.72% of PD mice, respectively. Immunohistochemical mechanism studies show AKT expression in Lpc-BoSA/CSO-Exe is 4.23 times that of PD mice and GSK-3β expression is reduced to 18.41%. Lpc-BoSA/CSO-Exe could reduce the production of α-synuclein and Lewy bodies through AKT/GSK-3β pathway, and effectively prevent the progressive deterioration of Parkinson's disease. In summary, Lpc-BoSA/CSO-Exe increases the entry of exenatide into brain and promotes its clinical application for Parkinson's disease therapy.

Cassia fistula L. bark fraction modulated GSK3β/ p53 expression for mitochondrial mediated apoptosis in HeLa cells

In Ayurveda, Cassia fistula L. commonly known as Aragvadha (disease killer) is highly valuable medicinal plant. In the present study, hexane fraction (CaMH), chloroform fraction (CaMC), ethyl acetate fraction (CaME) and methanol fraction (CaMM) isolated from C. fistula bark were explored for their cytotoxic potential against cervical carcinoma (HeLa), breast carcinoma (MCF-7) and osteosarcoma (MG-63) cell lines using MTT assay. Our results unveiled that C. fistula bark fractions were selectively cytotoxic to carcinoma cells and among the tested fractions CaMC fraction had highest selectivity index (SI) with a value of 9.77 in HeLa cells. CaMC fraction actuated apoptosis in HeLa cells, as evident from chromatin condensation, DNA fragmentation, externalization of phosphatidylserine, altered mitochondrial membrane potential and ROS generation. Moreover, CaMC fraction upregulated the expression of GSK3β and p53 which modulated the Bax/ Bcl-2 ratio and initiated the release of cytochrome c from mitochondria. The expression of caspase 3/9 was also found to be upregulated which ultimately induced apoptosis. We also found that CaMC induced cell cycle arrest at G0/G1 phase and significantly inhibited the migration in HeLa cells. GC–MS analysis showed Oleic Acid, Piperine, Isopiperine and Tris(2,4-di‑tert-butylphenyl) phosphate as major constituents which could be attributed to anticancer activity of CaMC. The present study affirms the potential of CaMC fraction in modulating the aberrant signaling pathway for the induction of apoptosis in HeLa cells.

Inhibition of hepatocellular carcinoma cell proliferation through regulation of the Cell Cycle, AGE-RAGE, and Leptin signaling pathways by a compound formulation comprised of andrographolide, wogonin, and oroxylin A derived from Andrographis Paniculata(Burm.f.) Nees

Ethnopharmacological relevanceIn 2020, liver cancer contributed to approximately 0.9 million new cases and 0.83 million deaths, making it the third leading cause of mortality worldwide. Andrographis paniculata (Burm.f.) Nees(APN), a traditional Chinese or ethnic medicine extensively utilized in Asia, has been historically employed for treating hepatitis and liver cancer. However, the precise molecular mechanism responsible for its therapeutic efficacy remains unclear. Aim of the studyTo identify and replace the active components of APN on liver cancer, which is investigate the potential of a Multi-Component Chinese Medicine derived from Andrographis paniculata (Burm.f.) Nees(APN-MCCN) for the treatment of liver cancer. Materials and methodsFirstly, the TCMSP database and two liver cancer disease databases were utilized to optimize the chemical constituents of APN and the disease-related targets of liver cancer. The network was constructed using Cytoscape to visualize the relationships between them. Subsequently, the optimal combination of components in APN-MCCN for the treatment of liver cancer was determined using the contribution index method. HPLC analysis was performed to measure the content of each component. Pathway enrichment and gene annotation were conducted using the ClueGo plugin. In vivo efficacy was evaluated by transplanting S180 and H22 tumor-bearing mouse models. In vitro efficacy was determined through MTT assay, morphological observations, flow cytometry analysis, and scratch tests. Western blotting was used to validate the protein expression. The transfection techniques were employed to knockdown the expressions of key protein in different pathway. ResultsWe obtained 24 effective compounds, with andrographolide contributing 20.78%, wogonin contributing 41.85%, and oroxylin A contributing 30.26% to the overall composition. Based on the predicted enrichment degree and correlation with liver cancer, we identified a total of 27 pathways, among which the Leptin signaling pathway, AGE-RAGE signaling pathway, and Cell Cycle signaling pathway were selected for further investigation. The content of andrographolide, oroxylin A, and wogonin in APN was found to be 0.104%, 0.0024%, and 0.0052%, respectively. In vivo experiments demonstrated that APN-MCCM significantly reduced tumor weight in S180 tumor-bearing mice and prolonged the survival time of H22 liver cancer-bearing mice. APN-MCCM exhibited inhibitory effects on the proliferation, apoptosis, and migration of liver cancer cells while arresting them in the G2/M phase. Furthermore, APN-MCCM down-regulated the protein expression of NCOA1, PTPN1, and GSK3B in the Leptin signaling pathway, NOS2 and NOS3 in the AGE-RAGE signaling pathway, CCNA2, CDK1, CDK2, and CDK7 in the Cell Cycle signaling pathway. Additionally, it upregulated the protein phosphorylation of p-P38 and p-JUN in the AGE-RAGE signaling pathway. Knockout experiments revealed that the inhibitory effect of APN-MCCM on liver cancer cell migration was prevented when the MAPK or NCOA1 genes were knocked out. Similarly, knocking out the CDK7 gene blocked the G2/M phase arrest induced by APN-MCCM in liver cancer cells. ConclusionsAPN-MCCM, consisting of andrographolide, wogonin, and oroxylin A, exhibits inhibitory effects on the cell proliferation of liver cancer cells by targeting the cell cycle pathway. Additionally, it suppresses the migration of liver cancer cells through the AGE-RAGE and Leptin signaling pathways.

Treatment with Blackberry Extract and Metformin in Sporadic Alzheimer's Disease Model: Impact on Memory, Inflammation, Redox Status, Phosphorylated Tau Protein and Insulin Signaling.

Natural products offer promising potential for the development of new therapies for Alzheimer's disease (AD). Blackberry fruits are rich in phytochemical compounds capable of modulating pathways involved in neuroprotection. Additionally, drug repurposing and repositioning could also accelerate the development of news treatments for AD. In light of the reduced brain glucose metabolism in AD, an alternative approach has been the use of the drug metformin. Thus, the aim of this study was to evaluate the effect of treatment with blackberry extract in a model of AD induced by streptozotocin (STZ) and compare it with metformin treatment. Male rats were divided into groups: I-Control; II-STZ; III-STZ + blackberry extract (100mg/kg); IV-STZ + blackberry extract (200mg/kg) and V-STZ + metformin (150mg/kg). The animals received intracerebroventricular injection of STZ or buffer. Seven days after the surgical procedure, the animals were treated orally with blackberry extract or metformin for 21days. Blackberry extract and metformin prevented the memory impairment induced by STZ. In animals of group II, an increase in acetylcholinesterase activity, phosphorylated tau protein, IL-6, oxidative damage, and gene expression of GSK-3β and Nrf2 was observed in the hippocampus. STZ induced a decrease in IL-10 levels and down-regulated the gene expression of Akt1, IRS-1 and FOXO3a. Blackberry extract and metformin prevented the alterations in acetylcholinesterase activity, IL-6, GSK3β, Nrf2, and oxidative damage. In conclusion, blackberry extract exhibits multi-target actions in a model of AD, suggesting new therapeutic potentials for this neurodegenerative disease.

Polyphyllin Ⅲ regulates EMT of lung cancer cells through GSK-3β/β-catenin pathway.

Some studies have found that the application of traditional Chinese medicine in the treatment of lung cancer has achieved satisfying results. Polyphyllin Ⅲ (PP Ⅲ) is a natural steroid saponin from P. polyphylla var. yunnanensis, and its analogs have played a wide role in anticancer research. This study aimed to investigate the effect of PP Ⅲ on the development of lung cancer and its molecular mechanism. A549 and NCI-H1299 cell lines were treated with PP Ⅲ in gradient concentration to detect the IC50 of the cells, and the optimal concentration was selected for subsequent experiments. The effects of PP III treatment on lung cancer were investigated in vitro and in vivo. In vitro experiments, it was found that the proliferation, invasion, migration, and colony formation ability of cancer cells were significantly reduced after PP III treatment, while accompanied by a large number of cell apoptosis. Further detection showed that N-cadherin was significantly decreased, E-cadherin was increased, and Snail and Twist were decreased in A549 cells and NCI-H1299 cells, respectively. In addition, GSK-3β expression was increased, while β-catenin expression was reduced with PP III treatment. In the mouse model, it was demonstrated that the volume of transplanted tumors was significantly reduced after PP Ⅲ treatment. PP Ⅲ has the capacity to inhibit the progression of lung cancer and regulate epithelial-mesenchymal transition through the GSK-3β/β-catenin pathway to suppress the malignant behavior of cancer cells. The application of PP Ⅲ is expected to be an effective method for the treatment of lung cancer.

Effect of estradiol after bacterial infection on the Wnt/β-catenin pathway in bovine endometrium epithelial cells and organoids

Endometritis is a disease caused by a postpartum bacterial infection with a poor prognosis that primarily affects dairy cows. Three-dimensional organoids have been used as a model for endometritis, because they exhibit a structure comparable to that of the endometrium, demonstrating both expansibility and hormone responsiveness. These characteristics render them an ideal platform for in vitro investigations of endometrial diseases. Estradiol (E2) is an endogenous steroid hormone with demonstrated anti-inflammatory properties, and the objective of this study was to determine the mechanism by which E2 modulates the inflammatory response and the Wnt signal transduction pathway in bovine endometrial epithelial cells and organoids following E. coli infection. We present the techniques for isolating and culturing primary bovine endometrial epithelial cells (BEECs), and producing endometrial organoids. For the experiments, the endometrial epithelial cells and organoids were infected with E. coli for 1 h, followed by incubation with E2 for 12 h. The mRNA and protein expressions of the inflammation-related genes, IL-1β, IL-6, TLR4, and NF-κB, as well as the Wnt pathway-related genes, Wnt4, β-catenin, c-Myc, and CyclinD1, were assessed using real-time quantitative-PCR and western blotting, respectively. The CCK8 viable cell counting assay was utilized to determine the optimal concentration of the Wnt inhibitor, IWR-1. The mRNA and protein expression of Wnt pathway-related genes was assessed following IWR-1 treatment, while the expression levels of proliferation-associated genes (Ki67, PCNA) and barrier repair genes (occludin, claudin, and Zo-1) in BEECs and organoids were evaluated after E2 treatment. The results of this study show that mRNA expression of the inflammatory genes, IL-1β, TLR4, and NF-κB (P < 0.05) decreased in BEECs following E2 treatment compared to the E. coli group. The protein expression of the IL-1β, IL-6, TLR4 and NF-κB genes was also inhibited (P < 0.05). Similar results were observed in tests on the organoids. Our findings demonstrate that E2 significantly upregulates the expression of Wnt-related genes, including β-catenin and c-Myc, while concurrently downregulating the expression of GSK3β (P < 0.05). Next, we treated E. coli-infected BEECs and organoids with the Wnt inhibitor, IWR-1. Compared with E. coli and E. coli + E2, the expression of mRNA and protein from Wnt 4, β-catenin, and CyclinD1 in E. coli + E2 and E. coli + IWR-1 was down-regulated (P < 0.05). The expression of the proliferation genes, Ki67, PCNA, and the tight junction genes, occludin, claudin1, and Zo-1, in organoids was significantly higher than that in BEECs (P < 0.05). In summary, we found strong potential for E2 mitigation of the E. coli-induced inflammatory response in BEECs and organoids, through activation of the Wnt pathway. In addition, the proliferation and repair capacity of organoids was much higher than that of BEECs.

Tetrahydrocurcumin Protects Against GSK3β/PTEN/PI3K/Akt-Mediated Neuroinflammatory Responses and Microglial Polarization Following Traumatic Brain Injury.

Tetrahydrocurcumin (THC) and microglial polarization play crucial roles in neuroprotection during traumatic brain injury (TBI). However, whether THC regulates microglial polarization in TBI is unknown. Thus, we intended to analyze the functions and mechanism of THC in nerve injury after TBI via the regulation of microglial polarization. A TBI rat model was established, and modified neurological function score (mNSS), brain water content, Nissl staining, and Fluoro-Jade B (FJB) staining were used to evaluate neurological function. The expression of the M1-linked markers CD16 and CD86, as well as the M2-associated markers CD206 and YM-1, was analyzed via qRT-PCR, western blotting, and immunofluorescence. The levels of inflammatory cytokines were assessed via ELISA. Primary microglia were isolated from the brain and treated with lipopolysaccharide (LPS) to induce injury. TUNEL staining was used to measure primary microglial apoptosis. The expression of GSK3β, PTEN, and PI3K/Akt pathway proteins was detected via western blotting. TBI induced nerve injury, while THC improved neurological function recovery after TBI. Further analysis indicated that THC enhanced M2 microglial polarization and attenuated the inflammatory reaction mediated by microglia both in vitro and in vivo. Moreover, we found that THC promoted the M2 microglial phenotype through upregulating GSK3β expression. Additionally, we proved that GSK3β activated the PI3K/Akt pathway by phosphorylating PTEN. In conclusion, we demonstrated that THC protected against nerve injury after TBI via microglial polarization via the GSK3B/PTEN/PI3K/Akt signaling axis, suggesting the potential of THC for TBI treatment by promoting microglial M2 polarization.

Therapeutic Potential Effect of Glycogen Synthase Kinase 3 Beta (GSK-3β) Inhibitors in Parkinson Disease: Exploring an Overlooked Avenue.

Parkinson's disease (PD) is a progressive neurodegenerative disease of the brain due to degeneration of dopaminergic neurons in the substantia nigra (SN). Glycogen synthase kinase 3 beta (GSK-3β) is implicated in the pathogenesis of PD. Therefore, the purpose of the present review was to revise the mechanistic role of GSK-3β in PD neuropathology, and how GSK-3β inhibitors affect PD neuropathology. GSK-3 is a conserved threonine/serine kinase protein that is intricate in the regulation of cellular anabolic and catabolic pathways by modulating glycogen synthase. Over-expression of GSK-3β is also interconnected with the development of different neurodegenerative diseases. However, the underlying mechanism of GSK-3β in PD neuropathology is not fully clarified. Over-expression of GSK-3β induces the development of PD by triggering mitochondrial dysfunction and oxidative stress in the dopaminergic neurons of the SN. NF-κB and NLRP3 inflammasome are activated in response to dysregulated GSK-3β in PD leading to progressive neuronal injury. Higher expression of GSK-3β in the early stages of PD neuropathology might contribute to the reduction of neuroprotective brain-derived neurotrophic factor (BDNF). Thus, GSK-3β inhibitors may be effective in PD by reducing inflammatory and oxidative stress disorders which are associated with degeneration of dopaminergic in the SN.

Restraint stress-induced effects on learning, memory, cognition, and expression of transcripts in different brain regions of mice.

Stress is one of the prevalent factors influencing cognition. Several studies examined the effect of mild or chronic stress on cognition. However, most of these studies are limited to a few behavioral tests or the expression of selected RNA/proteins markers in a selected brain region. This study examined the effect of restraint stress on learning, memory, cognition, and expression of transcripts in key learning centers. Male mice were divided into three groups (n = 6/group)-control group, stress group (adult stressed group; S), and F1 group (parental stressed group). Stress group mice were subjected to physical restraint stress for 2h before light offset for 2weeks. The F1 group comprised adult male mice born of stressed parents. All animals were subjected to different tests and were sacrificed at the end. Transcription levels of Brain-Derived Neurotrophic Factor (Bdnf), Tyrosine kinase (TrkB), Growth Associated Protein 43 (Gap-43), Neurogranin (Ng), cAMP Response Element-Binding Protein (Creb), Glycogen synthase kinase-3β (Gsk3β), Interleukine-1 (IL-1) and Tumour necrosis factor-α (Tnf-α) were studied. Results show that both adult and parental stress negatively affect learning, memory and cognition, as reflected by taking longer time to achieve the task or showing reduced exploratory behavior. Expression of Bdnf, TrkB, Gsk3β and Ng was downregulated, while IL-1 and Tnf-α were upregulated in the brain's cortex, thalamus, and hippocampus region of stressed mice. These effects seem to be relatively less severe in the offspring of stressed parents. The findings suggest that physical restraint stress can alter learning, memory, cognition, and expression of transcripts in key learning centers of brain.

A novel lncRNA TCONS_00071187 upregulated by activated GSK3β promotes high glucose-induced mesangial cell proliferation in the diabetic nephropathy.

Inhibiting mesangial cell proliferation is one of the strategies to control the early progression of diabetic nephropathy (DN). GSK3β is closely related to cell apoptosis as well as the development of DN, but whether it acts on the proliferation of mesangial cells is unclear. This study aimed to elucidate the role and mechanism of GSK3β-mediated lncRNA in high glucose-induced mesangial cell proliferation. HBZY-1 cells were used to establish the cell model of DN. The automatic cell counter was applied to assess cell proliferation. Flow cytometry was used to detect cell apoptosis and intracellular ROS levels. High-throughput transcriptomics sequencing was performed to detect the different expressions of long noncoding RNAs (lncRNAs) in the cell model of DN after knocking down the expression of GSK3β by the transfection of siRNA. The expression of RNA was detected by real-time PCR. In the cell model of DN using HBZY-1 cells, cell proliferation was enhanced accompanied by GSK3β activation and elevated apoptosis rate and reactive oxygen species (ROS) levels. A panel of novel lncRNAs, which were differentially expressed after GSK3β knockdown in the cell model of DN, were identified by high-throughput transcriptomics sequencing. Among them, the expression of TCONS_00071187 was upregulated under high glucose conditions while the knockdown of the GSK3β expression led to the downregulation of TCONS_00071187. The knockdown of TCONS_00071187 resulted in reduced mesangial cell proliferation, and decreased apoptosis rates and ROS levels. In conclusion, GSK3β promoted mesangial cell proliferation by upregulating TCONS_00071187, which led to enhanced ROS production under high glucose conditions in the cell model of DN. This study revealed the role of GSK3β medicated lncRNAs in the development of DN.

Neuroprotective potential of Erigeron bonariensis ethanolic extract against ovariectomized/D-galactose-induced memory impairments in female rats in relation to its metabolite fingerprint as revealed using UPLC/MS

Erigeron bonariensis is widely distributed throughout the world's tropics and subtropics. In folk medicine, E. bonariensis has historically been used to treat head and brain diseases. Alzheimer’s disease (AD) is the most widespread form of dementia initiated via disturbances in brain function. Herein, the neuroprotective effect of the chemically characterized E. bonariensis ethanolic extract is reported for the first time in an AD animal model. Chemical profiling was conducted using UPLC–ESI-MS analysis. Female rats underwent ovariectomy (OVX) followed by 42 days of D-galactose (D-Gal) administration (150 mg/kg/day, i.p) to induce AD. The OVX/D-Gal-subjected rats received either donepezil (5 mg/kg/day) or E. bonariensis at 50, 100, and 200 mg/kg/day, given 1 h prior to D-Gal. UPLC–ESI-MS analysis identified 42 chemicals, including flavonoids, phenolic acids, terpenes, and nitrogenous constituents. Several metabolites, such as isoschaftoside, casticin, velutin, pantothenic acid, xanthurenic acid, C18-sphingosine, linoleamide, and erucamide, were reported herein for the first time in Erigeron genus. Treatment with E. bonariensis extract mitigated the cognitive decline in the Morris Water Maze test and the histopathological alterations in cortical and hippocampal tissues of OVX/D-Gal-subjected rats. Moreover, E. bonariensis extract mitigated OVX/D-Gal-induced Aβ aggregation, Tau hyperphosphorylation, AChE activity, neuroinflammation (NF-κBp65, TNF-α, IL-1β), and apoptosis (Cytc, BAX). Additionally, E. bonariensis extract ameliorated AD by increasing α7-nAChRs expression, down-regulating GSK-3β and FOXO3a expression, and modulating Jak2/STAT3/NF-ĸB p65 and PI3K/AKT signaling cascades. These findings demonstrate the neuroprotective and memory-enhancing effects of E. bonariensis extract in the OVX/D-Gal rat model, highlighting its potential as a promising candidate for AD management.Graphical

Pharmacodynamic material basis and pharmacological mechanisms of Cortex Mori against diabetes mellitus

Ethnopharmacological relevanceThe application of Cortex Mori (CM) in the treatment of diabetes mellitus (DM) has been extensively documented in traditional medicine. In recent years, the chemical composition of CM has been gradually unraveled, and its therapeutic mechanism in treating DM, diabetic nephropathy, diabetic cardiomyopathy, and other related conditions has been highlighted in successive reports. However, there is no systematic study on the treatment of DM based on the chemical composition of CM. Aim of the studyThis study was conducted to systematically explore the hypoglycemic activity mechanism of CM based on its chemical composition. MethodsThe material basis of Cortex Mori extract (CME) was investigated through qualitative analyses based on liquid chromatography-mass spectrometry (LC-MS). The possible acting mechanism was simulated using network pharmacology and validated in streptozotocin (STZ) + high fat diet (HFD)-induced diabetic rats and glucosamine-induced IR-HepG2 model with the assistance of molecular docking techniques. ResultsA total of 39 compounds were identified in CME by the LC-MS-based qualitative analysis. In diabetic rats, it was demonstrated that CME significantly ameliorated insulin resistance, blood lipid levels, and liver injury. The network pharmacology analysis predicted five major targets, including AKT1, PI3K, FoxO1, Gsk-3β, and PPARγ. Additionally, three key compounds (resveratrol, protocatechuic acid, and kaempferol) were selected based on their predicted contributions. The experimental results revealed that CME, resveratrol, protocatechuic acid, and kaempferol could promote the expression of AKT1, PI3K, and PPARγ, while inhibiting the expression of FoxO1 and Gsk-3β. The molecular docking results indicated a strong binding affinity between resveratrol/kaempferol and their respective targets. ConclusionsCME contains a substantial amount of prenylated flavonoids, which may be the focal point of research on the efficacy of CM in the treatment of DM. Besides, CME is effective in controlling blood glucose and insulin resistance, improving lipid levels, and mitigating liver injury in patients with DM. Relevant mechanisms may be associated with the activation of the PI3K/Akt pathway, the inhibition of the expression of FoxO1 and Gsk-3β, and the enhancement of PPARγ activity. This study represents the first report on the role of CME in the treatment of DM through regulating PPARγ, FoxO1, and Gsk-3β.

Reconsidering repurposing: long-term metformin treatment impairs cognition in Alzheimer’s model mice

Metformin, a primary anti-diabetic medication, has been anticipated to provide benefits for Alzheimer’s disease (AD), also known as “type 3 diabetes”. Nevertheless, some studies have demonstrated that metformin may trigger AD pathology and even elevate AD risk in humans. Despite this, limited research has elucidated the behavioral outcomes of metformin treatment, which would hold significant translational value. Thus, we aimed to perform thorough behavioral research on the prolonged administration of metformin to mice: We administered metformin (300 mg/kg/day) to transgenic 3xTg-AD and non-transgenic (NT) C57BL/6 mice over 1 and 2 years, respectively, and evaluated their behaviors across multiple domains via touchscreen operant chambers, including motivation, attention, memory, visual discrimination, and cognitive flexibility. We found metformin enhanced attention, inhibitory control, and associative learning in younger NT mice (≤16 months). However, chronic treatment led to impairments in memory retention and discrimination learning at older age. Furthermore, metformin caused learning and memory impairment and increased levels of AMPKα1-subunit, β-amyloid oligomers, plaques, phosphorylated tau, and GSK3β expression in AD mice. No changes in potential confounding factors on cognition, including levels of motivation, locomotion, appetite, body weight, blood glucose, and serum vitamin B12, were observed in metformin-treated AD mice. We also identified an enhanced amyloidogenic pathway in db/db mice, as well as in Neuro2a-APP695 cells and a decrease in synaptic markers, such as PSD-95 and synaptophysin in primary neurons, upon metformin treatment. Our findings collectively suggest that the repurposing of metformin should be carefully reconsidered when this drug is used for individuals with AD.

HMGB1 enhances the migratory and invasive abilities of A2780/DDP cells by facilitating epithelial to mesenchymal transition via GSK‑3β.

The aim of the present study was to investigate the impact and mechanism of high mobility group box 1 (HMGB1) on the regulation of cell migration and invasion in A2780/DDP cisplatin-resistant ovarian cancer cells. After transfecting small interfering (si)RNA-HMGB1 into A2780/DDP cells, Transwell migration and invasion assays were conducted to assess alterations in the cell migratory and invasive abilities. Additionally, western blotting analyses were performed to examine changes in HMGB1, phosphorylated (p)-GSK-3β, GSK-3β, E-cadherin and vimentin expression levels. The results of the present study demonstrated that the migratory and invasive abilities of A2780/DDP cells were significantly higher compared with those of A2780 cells. Additionally, the expression levels of HMGB1, p-GSK-3β and the mesenchymal phenotype marker, vimentin, in A2780/DDP cells were significantly elevated relative to the levels in A2780 cells. Conversely, the expression level of the epithelial phenotype marker, E-cadherin, was markedly decreased compared with that in A2780 cells. Following transfection of A2780/DDP cells with siRNA-HMGB1, there was a significant reduction in the rate of cell migration and invasion. Simultaneously, the expression levels of HMGB1, p-GSK-3β and vimentin were downregulated while the level of E-cadherin was upregulated. It was therefore concluded that the high expression of HMGB1 in A2780/DDP cells enhanced the cell migration and invasion abilities by facilitating epithelial to mesenchymal transition via GSK-3β.

Oxidative stress in Alzheimer's disease: current knowledge of signaling pathways and therapeutics.

Alzheimer's disease's pathophysiology is still a conundrum. Growing number of evidences have elucidated the involvement of oxidative stress in the pathology of AD rendering it a major target for therapeutic development. Reactive oxygen species (ROS) generated by altered mitochondrial function, dysregulated electron transport chain and other sources elevate aggregated Aβ and neurofibrillary tangles which further stimulating the production of ROS. Oxidative stress induced damage to lipids, proteins and DNA result in neuronal death which leads to AD. In addition, oxidative stress induces apoptosis that is triggered by the modulation of ERK1/2 and Nrf2 pathway followed by increased GSK-3β expression and decreased PP2A activity. Oxidative stress exaggerates disease condition by interfering with various signaling pathways like RCAN1, CREB/ERK, Nrf2, PP2A, NFκB and PI3K/Akt. Studies have reported the role of TNF-α in oxidative stress stimulation that has been regulated by drugs like etanercept increasing the level of anti-oxidants. Other drugs like pramipexole, memantine, carvedilol, and melatonin have been reported to activate CREB/RCAN1 and Nrf2 pathways. In line with this, epigallocatechin gallate and genistein also target Nrf2 and CREB pathway leading to activation of downstream pathways like ARE and Keap1 which ameliorate oxidative stress condition. Donepezil and resveratrol reduce oxidative stress and activate AMPK pathway along with PP2A activation thus promoting tau dephosphorylation and neuronal survival. This study describes in detail the role of oxidative stress in AD, major signaling pathways involving oxidative stress induced AD and drugs under development targeting these pathways which may aid in therapeutic advances for AD.

Ketamine modulates disrupted in schizophrenia-1/glycogen synthase kinase-3β interaction.

Disrupted in schizophrenia-1 (DISC1) is a scaffolding protein whose mutated form has been linked to schizophrenia, bipolar affective disorders, and recurrent major depression. DISC1 regulates multiple signaling pathways involved in neurite outgrowth and cortical development and binds directly to glycogen synthase kinase-3β (GSK-3β). Since ketamine activates GSK-3β, we examined the impact of ketamine on DISC1 and GSK-3β expression. Postnatal day 7 rat pups were treated with ketamine with and without the non-specific GSK-3β antagonist, lithium. Cleaved-caspase-3, GSK-3β and DISC1 levels were measured by immunoblots and DISC1 co-localization in neurons by immunofluorescence. Binding of DISC1 to GSK-3β was determined by co-immunoprecipitation. Neurite outgrowth was determined by measuring dendrite and axon length in primary neuronal cell cultures treated with ketamine and lithium. Ketamine decreased DISC1 in a dose and time-dependent manner. This corresponded to decreases in phosphorylated GSK-3β, which implicates increased GSK-3β activity. Lithium significantly attenuated ketamine-induced decrease in DISC1 levels. Ketamine decreased co-immunoprecipitation of DISC1 with GSK-3β and axonal length. These findings confirmed that acute administration of ketamine decreases in DISC1 levels and axonal growth. Lithium reversed this effect. This interaction provides a link between DISC1 and ketamine-induced neurodegeneration.

An investigation on the alterations in Wnt signaling in ADHD across developmental stages

The canonical Wnt signaling pathway plays a vital role in the developmental processes of the Central Nervous System throughout both prenatal and postnatal stages, as well as in maintaining homeostasis during adulthood. Its complex intracellular cascade involves the participation of key proteins (i.e., GSK3β and β-catenin) to activate the transcription of Wnt target genes. These genes subsequently control processes like cell proliferation, maturation, and the determination of cell fate. Previous studies suggest that this pathway can also be associated with Attention-Deficit Hyperactivity Disorder (ADHD), a neurodevelopmental disorder with multifactorial etiology. This study aimed to clarify if and at what developmental stage the Wnt pathway is altered in ADHD. Accordingly, we carried out proteomic and functional assessments of the Wnt pathway using Western Blot and reporter assays, respectively. These assessments were performed at the induced pluripotent stem cell (iPSC), neural stem cell (NSC), and neuronal phases. IPSCs were generated from somatic cells retrieved from 5 controls and 5 patients diagnosed with ADHD. As opposed to the developmental stage of iPSCs, ADHD NSCs showed alterations in the protein expression of both GSK3β and β-catenin, suggesting increased Wnt activity in the ADHD group. Moreover, Wnt reporter assays confirmed higher Wnt activity in ADHD NSCs. Our molecular findings in NSCs correlated with genetic predisposition to ADHD and clinical traits displayed by their respective donors. In conclusion, these results suggest that a crucial cellular pathway is disrupted in patient-specific NSCs, potentially explaining the developmental deficits clinically exhibited by ADHD patients.

Hop (Humulus lupulus L.) extract reverts glycaemic imbalance and cognitive impairment in an animal model of obesity.

The rates of overweight and obesity around the world have increased in past years. The body's adipose tissue stimulates the antioxidant and oxidation imbalance capacity at the cellular level. This scenario favors an inflammatory low-grade systemic condition starting with insulin resistance, which in turn may involve diabetes mellitus type 2 and cognitive decline afterward. Neurological diseases have been correlated to senile age diseases over time. This scenario calls for a change in the incidence of obesity in the younger generation. An unhealthy dietary consumption together with sedentary habits might lead to poor gut absorption of nutrients. Several plants and foods have bioactive compounds that can reduce or inhibit radical scavengers, reactive oxygen species, and metal ion complexes that threaten the cerebral defense system. The bitter acids from hops (Humulus lupulus L.) have been demonstrated to have promising effects on lipid and carbohydrate metabolism improvement, reducing inflammatory responses through alpha acids, beta acids, and analogs action. Therefore, the current study aimed to investigate the bioactivity of hop bitter acids in obese and lean mice. For that, a dry hop extract (DHE) was obtained by applying carbon dioxide as the fluid of supercritical extraction. Afterward, seventy-eight male mice of the C57BL/6J strain were weighed and randomly distributed into six groups of 13 animals each according to the diet offered: (NO) normolipidic diet, (NO1) normolipidic diet containing 0.35% alpha acids, (NO2) normolipidic diet containing 3.5% alpha acids, (HP) hyperlipidic diet, (HP1) hyperlipidic diet containing 0.35% alpha acids, and (HP2) hyperlipidic diet containing 3.5% alpha acids. After applying the glycemic tolerance and insulin tolerance tests, a better stabilization of glycemia levels and weight gain among those animals fed with DHE (NO2 and HP2) were observed in comparison to the obese control group (HP) (p < 0.05). There was also an amelioration of antioxidant capacity observed by checking the enzymatic profile by SOD and an apparent mitigation of brain degeneration by checking GSK3β and p-IRS1 proteins expression (p < 0.05). The y-maze cognitive test applied to highlight possible obesity-harmful animal brains did not indicate a statistical difference between the groups. Although the weekly dietary intake between the obese HP2 group (33.32 ± 4.11, p < 0.05) and control HP (42.3 ± 5.88, p < 0.05) was different. The bioactive compounds present in DHE have demonstrated relevant effects on glycemic control, insulin signaling, and the consequent modulatory action of the obesity-related markers with the brain's inflammatory progression.

Evaluation of the effect of GSK-3β on liver cancer based on the PI3K/AKT pathway.

The PI3K/AKT/GSK-3β signaling pathway plays a pivotal role in numerous physiological and pathological processes, including cell proliferation, apoptosis, differentiation, and metabolic regulation. Aberrant activation of the PI3K/AKT pathway is intricately linked to development of tumor. GSK-3β, belonging to the serine/threonine protein kinase family, is crucial in the pathogenesis of liver cancer. As a key rate-limiting enzyme in the glucose metabolism pathway, GSK-3β significantly impacts the growth, proliferation, metastasis, and apoptosis of liver cancer cells. It is also implicated in chemotherapy resistance. Elevated expression of GSK-3β diminishes the sensitivity of liver cancer cells to chemotherapeutic agents, thereby playing a substantial role in the development of drug resistance. Consequently, targeting of GSK-3β, particularly within the PI3K/AKT signaling pathway, is regarded as a promising therapeutic strategy for liver cancer. The precise identification and subsequent modulation of this pathway represent a substantial potential for innovative clinical interventions in the management of liver cancer.