Search Results (263)

Obesity, type 2 diabetes (T2D), and insulin resistance are pervasive metabolic disorders marked by chronic low-grade inflammation and systemic metabolic disorders. The emerging field of immunometabolism highlights how interactions between immune processes and metabolic pathways in adipose tissue, liver, muscle, and pancreatic islets contribute to disease pathogenesis. Lipid dysregulation plays a central role in these processes, with distinct lipid molecules identified in obese patients as compared to lean patients that correlate with insulin resistance, inflammation, and vascular dysfunction. This Special Issue compiles a multidisciplinary body of research aimed at elucidating molecular mechanisms, identifying novel biomarkers, and exploring innovative therapeutic strategies. Key contributions include studies on omega-3 long-chain polyunsaturated fatty acids (LCPUFAs) and their differential associations with neurocognitive development; the potential of beta-defensin 2 as a biomarker linking gut-derived inflammation and metabolic dysfunction; and the promotion of adipocyte browning by Carnosic acid via AMPK activation and GSK3β inhibition. Additionally, reviews of phytochemicals underscore their multisystem therapeutic potential, while investigations into sodium–glucose cotransporter-2 (SGLT2) inhibitors suggest possible metabolic and neuroprotective benefits beyond glucose control. Maternal lipid metabolism during pregnancy and its impact on maternal fetal health further emphasize the clinical complexity of lipid dysregulation. Despite promising insights, significant gaps remain regarding causality versus correlation in lipid biomarkers, standardization of analytical methodologies, tissue heterogeneity, and unintended effects of metabolic interventions. Collectively, these studies underscore the necessity of integrative, mechanism-driven research to bridge fundamental biology with translational and clinical applications, ultimately advancing precision therapies for metabolic diseases. Full article

Excessive melanin production causes hyperpigmentation disorders such as freckles, melasma, and age spots, affecting appearance and quality of life. Tyrosinase is the key enzyme controlling melanin synthesis, and natural compounds are being explored as effective tyrosinase inhibitors. Fisetin, a dietary flavonoid found in fruits and vegetables like grapes and onions, is known for its anti-inflammatory and anticancer properties, but its anti-melanogenic activity remains unclear. This study demonstrated that fisetin, up to 60 μM, is non-toxic and significantly decreases tyrosinase activity and melanin content in human melanoma cells. Mechanistically, fisetin activates PKCα, leading to phosphorylation and degradation of β-catenin, thereby downregulating MITF expression. Additionally, it activates ERK and AKT/GSK3β pathways, promoting ubiquitination and proteasomal degradation of MITF, resulting in reduced levels of tyrosinase, TRP-1, and TRP-2. The proteasome inhibitor MG132 confirmed that fisetin accelerates β-catenin and MITF degradation. Additionally, inhibition of the PI3K/AKT pathway by LY294002 or the ERK pathway by PD98059 reversed fisetin’s reduction of tyrosinase activity and melanin synthesis, further verifying the participation of these pathways. Computational docking integrated with deep learning-based CNN scoring revealed that fisetin interacts with PKCα, β-catenin, tyrosinase, and TYRP1. Collectively, these findings suggest that fisetin exerts multi-targeted inhibitory effects on melanogenesis, highlighting its potential as a therapeutic and cosmetic agent for hyperpigmentation. Full article

Myotonic Dystrophy type 1 (DM1) is a complex disease affecting multiple tissues, including skeletal and cardiac muscles, the brain and the eyes. DM1 results from an expansion of CTG repeats in the 3′ UTR of the DMPK gene. Previously, we described that the small-molecule inhibitor of GSK3β, tideglusib (TG), reduces DM1 pathology in DM1 cell and mouse models by correcting the GSK3β-CUGBP1 pathway, decreasing the mutant CUG-containing RNA. Respectively, clinical trials using TG showed promising results for patients with congenital DM1 (CDM1). The drug development in DM1 human studies needs specific and noninvasive biomarkers. We examined the blood levels of active GSK3β in different clinical forms of DM1 and found an increase in active GSK3β in the peripheral blood mononuclear cells (PBMCs) in patients with CDM1, juvenile DM1 and adult-onset DM1 vs. unaffected patients. The blood levels of active GSK3β correlate with the length of CTG repeats and severity of muscle weakness. Thrombospondin and TGFβ, linked to the TG-GSK3β pathway in DM1, are also elevated in the DM1 patients’ blood. These findings show that the blood levels of active GSK3β might be developed as a potential noninvasive biomarker of muscle weakness in DM1. Full article

Background: Epithelial–mesenchymal transition (EMT) is a fundamental process that drives invasion and metastasis in patients with diffuse-type gastric cancer (DGC). The role of SMARCD3, a subunit of the SWI/SNF chromatin remodeling complex, in this process is largely unknown. The aim of this study is to elucidate the molecular mechanism through which SMARCD3 integrates with the PI3K-AKT and WNT/β-catenin signaling pathways to promote EMT and gastric cancer progression. Methods: Stable SMARCD3-overexpressing MKN45 and MKN74 cell lines were established. RNA sequencing (RNA-seq) was performed to investigate signaling alterations. Western blot analysis confirmed the expression of EMT markers (Snail and Slug) and the phosphorylation of AKT (Ser473) and GSK3β (Ser9). PI3K dependency was tested using the inhibitor LY294002. Cooperative effects were examined by activating the WNT pathway with WNT3A. Results: SMARCD3 overexpression upregulated PI3K-AKT and WNT signaling, which correlated with increased Snail/Slug expression and increased AKT/GSK3β phosphorylation. GSK3β inactivation (pSer9) stabilizes Snail, driving EMT. LY294002 treatment suppressed Snail/Slug expression, attenuated AKT activation, and reversed the mesenchymal phenotype. Furthermore, WNT3A treatment synergistically increased nuclear Snail accumulation. Conclusions: SMARCD3 acts as a critical epigenetic regulator that promotes EMT in patients with gastric cancer through the integration of the PI3K-AKT and WNT/β-catenin pathways. Targeting this SMARCD3-mediated mechanism offers a promising therapeutic strategy to inhibit metastasis and improve outcomes for patients with gastric cancer. Full article

Microcirculation in cutaneous tissue is essential to balance oxygen delivery and maintain the health of the skin. Senescence contributes to microcirculatory dysfunction through mechanisms involving chronic inflammation, structural remodeling of microvessels, and disturbances in hemodynamics. In this study we investigated the promoting effect of escin on blood flow through topical application. To elucidate the molecular mechanisms of escin, kinase phosphorylation changes in human umbilical vein endothelial cells (HUVECs) were examined. Escin stimulates the Wnt/β-Catenin and c-Jun N-terminal kinase (JNK) signaling pathway in cultured HUVECs. To clarify the target of escin in the Wnt/β-Catenin signaling pathway, gene expression in response to escin treatment was evaluated, and escin-mediated signaling activation was accompanied by glycogen synthase kinase-3 beta (Gsk3β), according to inhibitor studies performed with IWR1 (tankyrase inhibitor). In addition, the expression level of the Gsk3β were down-regulated by escin treatment in cultured HUEVCs. Escin also enhanced vascular remodeling, and, when applied topically, led to a sustained increase in cutaneous blood flow. Escin-mediated Wnt signaling activation could enhance blood vessel networks via Gsk3β down-regulation. In conclusion, our data demonstrate that escin promotes angiogenic behavior and enhances adenosine-induced perfusion in humans, thereby supporting its potential role in modulating cutaneous microcirculation. Full article

Intracellular emetic signals involved in the cannabinoid CB₁ receptor inverse agonist/antagonist SR141716A were investigated. SR141716A (20 mg/kg, i.p.)-evoked vomiting occurred via both the central and peripheral mechanisms. This was accompanied by robust emesis-associated increases in the following: (i) c-fos- and phospho-glycogen synthase kinase-3α/β (p-GSK-3αβ)-expression in the shrew’s dorsal vagal complex (DVC), (ii) phospho-extracellular signal-regulated kinase1/2 (p-ERK_1/2) expression in both the DVC and jejunal enteric nervous system, and (iii) time-dependent upregulation of cAMP levels and phosphorylation of protein kinase A (PKA), protein kinase B (Akt), GSK-3α/β, ERK_1/2, and protein kinase C αβII (PKCαβII) in the brainstem. SR141716A-evoked emetic parameters were attenuated by diverse inhibitors of the following: PKA, ERK_1/2, GSK-3, phosphatidylinositol 3-kinase (PI3K)-Akt pathway, phospholipase C (PLC), PKC, Ca²⁺/calmodulin-dependent protein kinase II (CaMKII), L-type Ca²⁺ channel (LTCC), store-operated Ca²⁺ entry (SOCE), inositol trisphosphate receptor (IP3R), ryanodine receptor (RyRs), both 5-HT₃-, and D_2/3-receptor antagonists, and the transient receptor potential vanilloid 1 receptor (TRPV1R) agonist. SR141716A appears to evoke vomiting via inverse agonist activity involving emesis-associated kinases, including cAMP/PKA, ERK_1/2, PI3K/Akt/GSK-3, PLC/PKCαβII, and CaMKII, which depend upon Ca²⁺ mobilization linking extracellular Ca²⁺ entry via plasma membrane Ca²⁺ channels (LTCC, SOCE, TRIPV1R) and intracellular Ca²⁺ release via IP3Rs and RyRs. The 5-HT₃, NK₁, and D_2/3 receptors also contribute to SR141716A-mediated vomiting. Full article

Crohn’s disease is a chronic, idiopathic inflammatory bowel disease characterized by patchy, transmural inflammation that is influenced by genetic, environmental, and microbial factors. The NOD2 pathway mediates NFκB activation and pro-inflammatory cytokine production. In the SHIP–/– murine model of Crohn’s disease-like ileitis, macrophage-derived IL-1β production drives intestinal inflammation. SHIP reduces NOD2 signaling by preventing downstream interaction between RIPK2 and XIAP, leading us to hypothesize that blocking RIPK2 in SHIP–/– mice would ameliorate intestinal inflammation. We examined the effects of RIPK2 inhibition on pro-inflammatory cytokine production in SHIP+/+ and SHIP–/– macrophages and in mice, using the RIPK2 inhibitor, GSK2983559. We found that GSK2983559 blocked RIPK2 activation in SHIP+/+ and SHIP–/– bone marrow-derived macrophages (BMDMs), and reduced Il1b transcription and IL-1β production in (MDP+LPS)-stimulated SHIP–/– BMDMs. Despite the reduction of IL-1β production in BMDMs, in vivo treatment with GSK2983559 worsened intestinal inflammation and increased IL-1β concentrations in the ileal tissues of SHIP–/– mice. GSK2983559 only modestly reduced IL-1β in (MDP+LPS)-stimulated SHIP–/– peritoneal macrophages, and did not suppress pro-inflammatory cytokine production in response to TLR ligands in peritoneal macrophages from either SHIP+/+ or SHIP–/– mice. Taken together, our data suggest that although RIPK2 inhibition can block IL-1β production by (MDP+LPS)-stimulated macrophages in vitro, it is not an effective anti-inflammatory strategy in vivo, highlighting the limitations of targeting RIPK2 to treat intestinal inflammation in the context of SHIP deficiency. Full article

Alzheimer’s disease (AD) is a prevalent neurodegenerative disorder with a pressing need for novel therapeutics. However, current medications only offer symptomatic relief, without tackling the underlying pathology. To explore the bioactive potential of marine-derived fungi, this study focused on Aspergillus terreus C23-3, a strain isolated from the coral Pavona cactus in Xuwen County, China, which showed a richer metabolite fingerprint among the three deposited A. terreus strains. AntiSMASH analysis based on complete genome sequencing predicted 68 biosynthetic gene clusters (BGCs) with 7 BGCs synthesizing compounds reported to have anti-AD potential, including benzodiazepines, benzaldehydes, butenolides, and lovastatin. Liquid chromatography coupled with mass spectrometry (LC-MS)-based combinational metabolomic annotation verified most of the compounds predicted by BGCs with the acetylcholinesterase (AChE) inhibitor territrem B characterized from its fermentation extract. Subsequently, molecular docking showed that these compounds, especially aspulvione B1, possessed strong interactions with AD-related targets including AChE, cyclin-dependent kinase 5-p25 complex (CDK5/p25), glycogen synthase kinase-3β (GSK-3β), and monoamine oxidase-B (MAO-B). In conclusion, the genomic–metabolomic analyses and molecular docking indicated that C23-3 is a high-value source strain for anti-AD natural compounds. Full article

Background/Objectives: Glycogen synthase kinase-3 beta (GSK3β) is a key enzyme involved in neurodegenerative diseases such as Alzheimer’s and Parkinson’s, contributing to tau hyperphosphorylation, amyloid-beta (Aβ) aggregation, and neuronal dysfunction. Methods: This study applied a machine learning-driven virtual screening approach to identify potent natural inhibitors of GSK3β. A dataset of 3092 natural compounds was analyzed using Support Vector Machine (SVM), Random Forest (RF), and K-Nearest Neighbors (KNN), with feature selection focusing on key molecular descriptors, including lipophilicity (ALogP: −0.5 to 5.0), hydrogen bond acceptors (0–10), and McGowan volume (0.5–2.5). RF outperformed SVM and KNN, achieving the highest test accuracy (83.6%), specificity (87%), and lowest RMSE (0.3214). Results: Virtual screening using AutoDock Vina and molecular dynamics simulations (100 ns, GROMACS 2022) identified artemisinin as the top GSK3β inhibitor, with a binding affinity of −8.6 kcal/mol, interacting with key residues ASP200, CYS199, and LEU188. Dihydroartemisinin exhibited a binding affinity of −8.3 kcal/mol, reinforcing its neuroprotective potential. Pharmacokinetic predictions confirmed favorable drug-likeness (TPSA: 26.3–70.67 Ų) and non-toxicity. Conclusions: While these findings highlight artemisinin-based inhibitors as promising candidates, experimental validation and structural optimization are needed for clinical application. This study demonstrates the effectiveness of machine learning and computational screening in accelerating neurodegenerative drug discovery. Full article

Metabolic syndrome (MetS) poses considerable toxicological risks due to its association with an increased likelihood of metabolic dysfunction-associated steatotic liver disease (MASLD), and is characterized by hypertension, hyperglycemia, dyslipidemia, and obesity. This study aimed to investigate the therapeutic potential of flavonoid-rich lotus seedpod extract (LSE) in alleviating MetS and MASLD-related hepatic disturbances. In vivo, mice subjected to a high-fat diet (HFD) and streptozotocin (STZ) injection were supplemented with LSE or simvastatin for 6 weeks. Obesity indicators included body weight and epididymal fat, while insulin resistance was measured by fasting serum glucose, serum insulin, homeostasis model assessment–insulin resistance index (HOMA-IR), and oral glucose tolerance (OGTT). Also, the levels of serum lipid profiles and blood pressure were evaluated. Adipokines, proinflammatory cytokines, liver fat droplets, and peri-portal fibrosis were analyzed to clarify the mechanism of MetS. LSE significantly reduced the HFD/STZ-induced MetS markers better than simvastatin, as demonstrated by hypoglycemic, hypolipidemic, antioxidant, and anti-inflammatory effects. In vitro, LSE improved oleic acid (OA)-triggered phenotypes of MASLD in hepatocyte HepG2 cells by reducing lipid accumulation and enhancing cell viability. This effect might be mediated through proteins involved in lipogenesis that are downregulated by adenosine monophosphate-activated protein kinase (AMPK). In addition, LSE reduced reactive oxygen species (ROS) generation and glycogen levels, as demonstrated by enhancing insulin signaling involving reducing insulin receptor substrate-1 (IRS-1) Ser307 phosphorylation and increasing glycogen synthase kinase 3 beta (GSK3β) and protein kinase B (PKB) expression. These benefits were dependent on AMPK activation, as confirmed by the AMPK inhibitor compound C. These results indicate that LSE exhibits protective effects against MetS-caused toxicological disturbances in hepatic carbohydrate and lipid metabolism, potentially contributing to its efficacy in preventing MASLD or MetS. Full article

Influenza A virus (IAV) infections continue to threaten public health. Current strategies, such as vaccines and antiviral drugs, are limited due to their time-consuming development and drug-resistant strains. Therefore, new effective treatments are needed. Here, virus-supportive cellular factors are promising drug targets, and the encapsulation of candidate substances in poly(D,L-lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) is intended to improve their bioavailability. This study investigates the potential of the indirubin derivative 6-bromoindirubin-3′-glycerol-oxime ether (6BIGOE), a glycogen synthase kinase 3 (GSK-3)β inhibitor, for its potential to regulate IAV replication in vitro. The effects of 6BIGOE-loaded PLGA NPs on cell metabolism were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays in A549 and Calu-3 cells. Viral replication and spread were monitored in various IAV-infected cell lines in the absence and presence of free and 6BIGOE-loaded PLGA NPs via plaque assays and Western blot analysis. The encapsulation of 6BIGOE in PLGA NPs resulted in reduced negative side effects on cell viability while maintaining antiviral efficacy. Both encapsulated and free 6BIGOE exhibited antiviral activity, potentially through GSK-3β inhibition and the disruption of key signaling pathways required for viral replication. The data indicate 6BIGOE, particularly after encapsulation in NPs, as a potential candidate for further investigation and development as an antiviral agent to treat IAV infections. Full article

Glycogen synthase kinase-3 beta (GSK-3β) plays a crucial role in multiple cellular processes and is implicated in different types of cancers and neurological disorders, including Alzheimer’s disease. Despite extensive efforts to develop novel GSK-3β inhibitors, the discovery of potent and selective lead compounds remains a challenge. In this study, we evaluated the GSK-3β inhibitory potential of semisynthetic flavonoid derivatives, which exhibited sub-micromolar activity. To gain further insights, we employed molecular docking, molecular dynamics simulations, and pharmacokinetic profile predictions. The docking studies revealed that the most potent inhibitor, compound 10, establishes key interactions with the ATP-binding site. Molecular dynamics simulations further confirmed that compound 10 maintains stable interactions with GSK-3β throughout the simulation. Additionally, pharmacokinetic predictions identified compound 3 as a promising candidate for Alzheimer’s disease therapy due to its ability to cross the blood–brain barrier. These findings suggest that, within the studied flavonoid derivatives, these compounds (particularly 10 and 3) hold potential as lead compounds for GSK-3β inhibition. The combination of strong enzymatic inhibition, stable binding interactions, and favorable pharmacokinetic properties highlights their promise for further development in cancer and neurodegenerative disease research. Full article

Multitarget drug discovery, including host-directed therapy, is particularly promising for tuberculosis (TB) due to the resilience of Mycobacterium tuberculosis (Mtb) as well as the complexity of the host’s immune response. In this proof-of-concept study, we used high-content imaging to test a novel panel of dual glycogen synthase kinase 3 beta (GSK-3β) and histone deacetylase (HDAC) 1 and 6 inhibitor candidates for their efficacy in reducing the growth of green fluorescent protein (GFP)-expressing mycobacteria in human primary macrophages. We demonstrate that all ten test compounds, also including the GSK-3β inhibitor SB415286, exhibit an antimycobacterial effect of 20–60% at low micromolar doses and are non-toxic to host cells. Mtb growth showed a positive correlation with the respective 50% inhibitory concentration (IC50) values of GSK-3β, HDAC1, and HDAC6 in each compound, indicating that compounds with a potent IC50 value for HDAC1, in particular, corresponded to higher antimycobacterial activity. Furthermore, the results from multiparametric flow cytometry and a customized multiplex RNA array demonstrated that SB415286 and selected compounds, C02 and C06, could modulate immune polarization and inflammation in Mtb-infected macrophages involving an enhanced expression of CCL2, IL-10 and S100A9, but a decrease in inflammatory mediators including COX-2, TNF-α, and NFκB. These data suggest that GSK-3β inhibition alone can decrease the intracellular growth of mycobacteria and regulate macrophage inflammation, while dual GSK-3β/HDAC inhibitors enhance this efficacy. Accordingly, the tailored design of dual GSK-3β/HDAC inhibitors could represent an innovative approach to host-directed therapy in TB. Full article

Background: Diabetic kidney disease (DKD) represents a chronic microvascular complication with diabetes, affecting around one-third of diabetic individuals. Despite current therapies, progression to end-stage kidney disease remains a challenge. Abnormal hyperphosphorylation of the Tau protein is implicated in various age-related diseases. This study aimed to explore the link between renal Tau protein hyperphosphorylation and kidney damage in type 2 diabetes mellitus (T2DM). Methods: Sprague Dawley rats were administered lithium chloride (LiCl), an inhibitor of a glycogen synthase kinase-3 (GSK3) inhibitor known to reduce Tau hyperphosphorylation. LiCl was administered either daily or every other day at a dosage of 1 mmol/kg. The effects of LiCl on kidney function were assessed through proteinuria, the kidney-to-bodyweight ratio, inflammation, fibrosis, and TGF-β1 expression levels. Results: Diabetic rats exhibited increased proteinuria, renal hypertrophy, inflammation, fibrosis, and elevated TGF-β1 expression. Lithium chloride treatment reduced kidney hypertrophy, inflammation, and fibrosis, indicating that Tau hyperphosphorylation contributes to the pathogenesis of DKD. LiCl also regulated TGF-β1 expression, which was associated with improved renal outcomes. Conclusions: The inhibition of Tau hyperphosphorylation by lithium chloride offers a potential therapeutic strategy for mitigating kidney damage in diabetic kidney disease. This study proposes LiCl as a novel treatment approach to attenuate DKD progression. Full article

Chronic kidney disease (CKD) involves inflammation, oxidative stress, and fibrosis, leading to renal dysfunction. Dapagliflozin, an SGLT2 inhibitor, shows renoprotective effects beyond glucose control, but its precise molecular mechanisms remain unclear. This study utilizes network pharmacology and molecular docking to elucidate its multi-target effects in CKD. Dapagliflozin’s SMILES structure was analyzed for ADMET properties. Potential targets were identified via SwissTargetPrediction, GeneCards, and SEA, and common CKD-related targets were determined. A protein–protein interaction (PPI) network was constructed, and key pathways were identified using GO and KEGG enrichment analyses. Molecular docking was conducted to validate dapagliflozin’s binding affinities with hub proteins. A total of 208 common targets were identified, including EGFR, GSK3β, and IL-6. GO and KEGG analyses highlighted key pathways, such as PI3K-Akt, MAPK, and AGE-RAGE, involved in inflammation, oxidative stress, and metabolic regulation. Molecular docking confirmed strong binding affinities with EGFR (−8.42 kcal/mol), GSK3β (−7.70 kcal/mol), and IL-6 (−6.83 kcal/mol). Dapagliflozin exhibits multi-target therapeutic potential in CKD by modulating inflammation, oxidative stress, and metabolic pathways. This integrative approach enhances the understanding of its mechanisms, supporting future experimental validation and clinical application in CKD management. Full article