Search Results (1,756)

The cytoplasmic accumulation of TDP-43 aggregates remains a persistent pathological hallmark of neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and limbic-predominant age-related TDP-43 encephalopathy (LATE). The cell’s natural clearance mechanisms, the Ubiquitin-Proteasome System (UPS) and the autophagy-lysosome pathway (ALP), are hypothesized to fail, at least in part, due to the sequestration of key components of these pathways by pathological TDP-43 species, thereby impairing autophagosome-lysosome fusion and lysosomal competence. Classical autophagic activators (e.g., rapamycin) can initiate upstream steps in the pathway but cannot address downstream flux bottlenecks, limiting their ability to restore effective TDP-43 clearance. This review revisits classical strategies and discusses newer approaches to modulate TDP-43 clearance, including transcription factor EB (TFEB) activators, proteolysis-targeting chimeras (PROTACs), and antisense oligonucleotides (ASOs). We propose that adopting multi-targeting strategies and developing better biomarkers are vital for clinical success. Full article

Introduction and Background: High-grade serous ovarian carcinoma (HGSOC) is notorious for its poor prognosis owing to its inherent biological aggressiveness and development of chemoresistance. The mechanistic target of rapamycin (mTOR) pathway is dysregulated in 55% of epithelial ovarian cancers, representing an appealing therapeutic target. To date, the clinical trials of mTOR inhibitors have shown modest response. In this study, we investigated the mTOR pathway in a clinical cohort of primary, chemo-naive, high-grade ovarian cancer samples, along with its regulatory post-transcriptional miRNA regulation. Methodology: We performed differential gene expression analysis on 100 HGSOC patients from TCGA and 80 healthy controls (i.e., normal ovarian tissue) from GTEx. The differentially expressed genes (DEGs) were overlaid onto the KEGG mTOR signalling pathway, followed by functional enrichment analysis. Next, we conducted differential miRNA expression analysis on the same cohort and identified regulatory miRNA–mTOR gene pairs involved in cancer pathogenesis. Finally, we constructed an interaction network and identified key hub genes and miRNAs with potential prognostic significance. Results: We identified 95 mTOR pathway genes that were significantly differentially expressed, involving upstream regulators, core components, and downstream effectors. Functional pathway analysis revealed a prominent shift toward mTORC1 activation, accompanied by paradoxical activation of autophagy. The let-7 miRNA family was identified as a key regulator of the mTOR pathway, potentially facilitating disease progression. RICTOR downregulation, a key component of the mTORC2 complex, appears to play a critical role in this histotype. In addition, FNIP1, a tumour suppressor gene implicated in mTOR dysregulation, was found to correlate with survival outcomes. Conclusions: We propose a model of dual activation of mTORC1 and autophagy in HGSOC as the metabolic rewiring enabling cancer progression under nutrient and cellular stress. Full article

Prostate cancer (PCa) is the most general cancer in men and is often linked with distant metastasis in its later stages. The caffeic acid (CA) derivative, N-(4-methoxyphenyl)methylcaffeamide (MPMCA), demonstrates superior liver-protective effects compared to CA. Nevertheless, the functions of MPMCA on prostate cancer metastasis remain unclear. Here, we demonstrate that MPMCA blocks migration and invasion in prostate cancer cells without affecting cell viability. By suppressing the production of mesenchymal markers Vimentin, N-cadherin and β-catenin and upregulating the production of the epithelial marker Zonula Occludens-1 (ZO-1), MPMCA also controls Epithelial–Mesenchymal Transition (EMT). The Phosphoinositide 3-kinase (PI3K), Protein kinase B (AKT) and mechanistic target of rapamycin (mTOR) pathway has been documented to regulate MPMCA-inhibited cell motility. Transfection with Snail and Slug cDNA reverses MPMCA’s suppression of EMT, migration, and invasion in prostate cancer cells. Importantly, our in vivo data indicates that MPMCA reduces Snail and Slug expression and prostate cancer metastasis. Our evidence suggests that MPMCA is a novel therapeutic candidate for treating metastatic prostate cancer. Full article

Tuberous Sclerosis Complex (TSC) is a genetic disorder caused by mutations that inactivate TSC1 or TSC2 genes. TSC1 or TSC2 mutations activate the mammalian target of rapamycin complex 1 (mTORC1) protein kinase pathway. Although many patients inherit a single copy of a mutant TSC gene, somatic mutations that cause loss of heterozygosity in inhibitory neuroprogenitor cells are hypothesized to be one cause of abnormal development. This may lead to cortical malformations or benign growths along the ventricular-subventricular zone (V-SVZ), cortex, olfactory tract, and olfactory bulbs (OB). This idea is supported by focal single-cell knockout experiments that induce CRE-mediated recombination following neonatal electroporation of conditional Tsc2 or Tsc1 mice. Loss of Tsc2 causes mTORC1 pathway activation and the formation of striatal hamartomas composed of ectopic clusters of abnormal cells and cytomegalic neurons, including within the OB. Neural phenotypes in this model can be partially rescued with Rapalink-1, a bisteric mTOR inhibitor, demonstrating the importance of mTOR in pathogenesis. We previously demonstrated that global V-SVZ neural stem cell (NSC) Tsc2 mutation induced by nestin-CRE-ER^T2 causes mTORC1 pathway activation, which is accompanied by transcriptional and translational errors. While we previously described cultured NSCs and OB granule cells from these mice, we did not thoroughly describe changes outside this region. Here, we provide evidence that removal of Tsc2 from neonatal V-SVZ NSCs causes subtle and rare brain malformations. This is exemplified by ectopic clusters of cytomegalic neurons and mTORC1 activation. This data supports that loss of Tsc2 in NSCs during neonatal development leads to heterotopic clusters in the adult brain. This model may be useful to study TSC, but the rarity and stochastic nature of lesions make the use challenging for identifying mechanisms and testing therapies. Full article

Autophagy is a critical cellular mechanism that regulates the degradation of misfolded and aggregated proteins and non-functional intracellular organelles. Based on the fundamental qualities of the substrates targeted for degradation and the distinct molecular mechanisms involved, autophagy can be classified into three major types: macroautophagy, microautophagy, and chaperone-mediated autophagy (CMA). Sequestosome 1 (SQSTM1)/p62, which functions as a signaling hub integrating nuclear factor kappa B (NF-κB), the mechanistic target of rapamycin complex 1 (mTORC1), and Kelch-like ECH-associated protein 1 (Keap1)–nuclear factor erythroid 2–related factor 2 (NRF2) pathways, serves as a selective macroautophagy/autophagy receptor that binds ubiquitinated cargo proteins and recruits them to the autophagosome for subsequent degradation in the autolysosome. Furthermore, the phase separation of p62 is an important regulatory process in the autophagy mechanism, but recent studies have demonstrated that impaired or excessive autophagy mediated by p62 is associated with cancer development. This review summarizes the role of autophagy—including its types, mechanisms, and the pathway related to the ubiquitin-dependent selective autophagy receptor p62—in cancer progression. Full article

The white-backed planthopper (Sogatella furcifera) is a major pest in rice-growing regions worldwide. It severely limits rice production through piercing–sucking feeding, oviposition injury, and by efficiently transmitting the Southern Rice Black-Streaked Dwarf Virus (SRBSDV). Previous studies demonstrated that the dark septate endophytic fungus Ochroconis guangxiensis strain X22 exhibits control activity against SRBSDV. To further evaluate its biocontrol potential, this study investigated the effects of the X22 strain on S. furcifera, the primary vector of SRBSDV. In this study, we established an X22–rice symbiotic system to evaluate its effects on the biological traits of S. furcifera. The results showed that, compared with a clear water treatment, the X22 strain significantly reduced the feeding amount (29.02%), egg-laying amount (12.30%), and hatching rate (11.58%) of S. furcifera. Gene expression analysis showed that the relative expression levels of the Target of Rapamycin (TOR) and vitellogenin (Vg) genes in one-day-old S. furcifera from the X22 treatment group were modestly downregulated, although no significant differences were detected compared with the control. Enzyme activity assays revealed that between 72 and 120 h post-treatment, the activities of detoxification enzymes, including carboxylesterase (CarE) and acetylcholinesterase (AChE), generally declined following X22 exposure. In contrast, the activities of protective enzymes, superoxide dismutase (SOD) and catalase (CAT), as well as certain digestive enzymes, α-amylase (α-AL) and trypsin, were induced. Conversely the activities of glutathione peroxidase (GSH-Px) and lipase (LPS) were suppressed. However, the physiological mechanisms underlying its effect on S. furcifera remain unclear. Collectively, these results demonstrate that the O. guangxiensis X22 strain inhibits S. furcifera reproduction by disrupting its physiological metabolism through multiple pathways, providing a mechanistic basis for its development as an environmentally friendly biocontrol agent. Full article

Pancreatic ductal adenocarcinoma (PDAC) is characterized by immune cell dysfunction and poor prognosis. CD44, a cell surface glycoprotein with multiple splice variants, has been implicated in tumor progression, but its compartment-specific roles in PDAC remain unclear. CD44 standard and variant isoform expression was analyzed in patient-derived lymph nodes (LNs) by quantitative PCR. Immune cell-specific CD44 expression was assessed by flow cytometry in LNs and peripheral blood. Soluble and exosome-associated CD44 (exo-CD44) were measured in plasma. Clinical associations and survival analyses were performed. Transcriptomic, immune infiltration, immune checkpoint, and drug sensitivity analyses were conducted using TCGA-PAAD and pharmacogenomic datasets. CD44 standard isoform expression was unchanged in PDAC LNs, whereas multiple CD44 variant isoforms (v4–v10) were significantly reduced and associated with metastatic disease and poor survival, particularly CD44v5, v6, v7, and v10. CD44 expression was enriched in CD45⁺ immune cells, with highest levels in CD4⁺ T cells in both LNs and blood. Soluble CD44 levels showed no clinical associations. In contrast, exo-CD44 levels were reduced overall in PDAC but increased in patients with distant metastasis, positive resection margins, systemic inflammation, and reduced survival. High CD44 expression was associated with advanced disease, immune cell infiltration, immune checkpoint gene expression, reduced sensitivity to gemcitabine, paclitaxel, rapamycin, and FMK, and distinct CTLA4/PD-L1 checkpoint profiles. CD44 exhibits compartment-specific regulation in PDAC, linking immune remodeling, exosome signaling, and therapeutic resistance to adverse clinical outcome. Full article

In sports nutrition, performance adaptation emerges from the coordinated molecular interaction between physical training and nutrient availability. This narrative review with conceptual synthesis advances Training–Fuel Coupling (TFC) as a systems physiology framework that conceptualizes nutrient availability, timing, and recovery feeding as molecular control variables proposed to govern exercise-induced adaptation. Integrating evidence from exercise metabolism and nutritional science, the model conceptualizes how substrate availability may modulate the dynamic crosstalk between AMP-activated protein kinase (AMPK) and mechanistic target of rapamycin (mTOR), shaping metabolic flexibility, anabolic recovery, and long-term performance optimization. Low-energy and low-glycogen contexts preferentially activate AMPK-dependent pathways supporting mitochondrial remodeling and oxidative efficiency, whereas nutrient-replete states facilitate mTOR-mediated protein synthesis and structural restoration. When strategically alternated through chrono-nutrition and nutritional periodization, these energetic states are hypothesized to generate oscillatory signaling patterns that enhance adaptive efficiency while limiting chronic metabolic strain. From a sports nutrition perspective, TFC provides a mechanistic rationale for energy availability management, recovery nutrition, and the prevention of maladaptive states such as Relative Energy Deficiency in Sport (RED-S). By reframing nutrients as regulatory signals rather than passive fuel, this framework integrates molecular nutrition with performance physiology, offering a unifying, systems-level and hypothesis-generating perspective on training–nutrition interactions that delineates testable pathways for future empirical investigation. Full article

Stem cells maintain tissue homeostasis through precisely regulated self-renewal and differentiation, processes largely dependent on metabolic control. The Drosophila testis provides an ideal model system to study metabolism regulation of stem cell homeostasis due to many advantages, including its well-defined stem cell niche architecture and genetic tractability. Recent studies have revealed that germline stem cells (GSCs) and somatic cyst stem cells (CySCs) exhibit distinct metabolic profiles. In particular, GSCs exhibit a metabolic feature closely associated with mitochondrial dynamics, lipid metabolism, and redox homeostasis, all of which are essential for maintaining their stem identity through the regulation of TOR (Target of Rapamycin) signaling. Nutrient sensing through the insulin/TOR, BMP, and JAK-STAT pathways integrates nutritional cues with developmental programs. Lipid metabolism and membrane homeostasis further contribute to the maintenance of stem cells. Metabolic intermediates function as signaling molecules, modulating niche-stem cell interactions and epigenetic modifications in stem cells. Hence, dysregulation of metabolic homeostasis can lead to stem cell depletion and age-related reproductive decline. This review synthesizes the current understanding of metabolic regulation in Drosophila testis stem cell maintenance, identifies critical knowledge gaps, and explores future research directions such as spatial/temporal metabolomics approaches. Lastly, we highlight how these insights may help understand mammalian stem cell biology and regenerative medicine. Full article

Painful diabetic neuropathy (PDN) is a prevalent and debilitating complication of diabetes, characterized by persistent neuropathic pain that severely impairs quality of life. Current management strategies predominantly target peripheral nerve dysfunction and offer only symptomatic relief, with no disease-modifying therapies available. Emerging evidence now underscores the critical role of central nervous system (CNS) glial cells—microglia, astrocytes, and oligodendrocytes, collectively termed the “glial triad”—in driving PDN pathogenesis. This review synthesizes recent advances elucidating how these glial cells contribute to neuroinflammation, metabolic dysregulation, and central sensitization. We detail specific mechanisms including microglial NLR Family Pyrin Domain Containing 3 (NLRP3) inflammasome activation and metabolic reprogramming, astrocytic aquaporin-4 (AQP4) polarity disruption impairing glymphatic function, and oligodendrocyte myelination deficits via Mammalian Target of Rapamycin (mTOR) signaling. Furthermore, we discuss the translational potential of glia-derived biomarkers (e.g., Translocator Protein (TSPO), Glial Fibrillary Acidic Protein (GFAP), myelin basic protein (MBP)) for early diagnosis and patient stratification. Finally, we highlight promising therapeutic avenues that target glial pathways, such as interleukin-35 (IL-35), β-hydroxybutyrate, and metformin, which aim to shift the treatment paradigm from symptomatic control to disease modification. By integrating preclinical and clinical insights, this review proposes the glial triad as a central player in PDN and suggests that targeted glial interventions may represent a promising frontier for future disease-modifying strategies. Full article

Exercise adaptation depends on a dynamic alternation between catabolic and anabolic states coordinated primarily by AMP-activated protein kinase (AMPK) and mechanistic target of rapamycin (mTOR). While transient activation of these pathways underpins beneficial molecular remodeling, the system-level consequences of sustained anabolic drive remain insufficiently conceptualized in exercise biology. This article presents a conceptual mechanistic narrative review integrating evidence from molecular nutrition, exercise physiology, redox biology, and epigenetic regulation to define limits of adaptive signaling. We propose the Metabolic Overdrive Model, a systems-level framework describing the transition from adaptive AMPK–mTOR oscillation to a high-anabolic lock-in state characterized by persistent mTORC1 activation, suppressed AMPK signaling, altered NAD⁺ economy (SIRT1–PARP imbalance), redox dysregulation, and progressive epigenetic drift. Using exercise and training as models of sustained metabolic stress, we synthesize mechanistic parallels across energy sensing, oxidative signaling, and chromatin regulation without implying pathological causality. The framework generates testable predictions linking prolonged post-exercise anabolic signaling (>24 h) to specific molecular signatures, including AMPK phosphorylation status, NAD⁺ availability, PARylation, histone acetylation, and DNA methylation dynamics. By reframing exercise adaptation as a loss-of-oscillation phenomenon rather than a linear continuum, this model provides a mechanistic language for hypothesis generation, biomarker-guided periodization, and future experimental validation. Full article

Objective: Hepatic ischemia–reperfusion injury (HIRI) is a common pathological condition in liver surgery and transplantation, and cellular pyroptosis plays a key role in its pathogenesis. However, the clinical application of curcumin is limited by its poor water solubility and low bioavailability. This study aims to develop mesenchymal stem cell (MSC)-derived exosomes loaded with curcumin (Exo-Cur). It also investigates the role and mechanism of Exo-Cur in inhibiting HIRI-related cellular pyroptosis. Methods: The preparation of Exo-Cur was optimized using orthogonal experimental design. Its solubility, stability, particle size distribution, and zeta potential were then evaluated. The morphology of Exo-Cur and its uptake in hepatocytes were observed using laser scanning confocal microscopy. The effect of Exo-Cur on HIRI was assessed through hematoxylin and eosin (HE) staining, ALT and AST measurements, TUNEL assay, CCK-8 assay, and lactate dehydrogenase (LDH) assay. Inflammatory cytokine protein levels were quantified by ELISA, and their mRNA expression was assessed by qRT-PCR. Pyroptosis was assessed by Western blot, immunohistochemistry, and flow cytometry. Additionally, protein expression changes in the PI3K/Akt/mTOR signaling pathway were analyzed using Western blot. Results: Orthogonal experiments determined that the optimal preparation method for Exo-Cur involves cell density at 95%, a curcumin concentration of 30 μg/mL, and a co-cultivation time of 12 h. Characterization results showed that Exo-Cur maintained its typical cup-shaped structure as well as stable particle size and zeta potential. Additionally, its water solubility and its stability in vitro were significantly improved compared to free curcumin. Further mechanistic studies indicated that Exo-Cur could ameliorate the abnormal morphology resulting from HIRI-induced hepatocyte pyroptosis, reduce the proportion of pyroptotic cells, and significantly downregulate the expression of NLRP3 inflammasome and downstream pyroptosis-related proteins (ASC, C-Caspase-1, GSDMD-N). Pathway analysis revealed that Exo-Cur activates the PI3K/Akt/mTOR axis, a pathway inhibited by HIRI. Moreover, rapamycin, an inhibitor of this pathway, reverses Exo-Cur’s anti-pyroptosis effect. Conclusions: This study develops an efficient and stable Exo-Cur delivery system, confirming its protective effect against HIRI by activating the PI3K/Akt/mTOR axis and inhibiting NLRP3-mediated cellular pyroptosis. This innovative combination of MSC-derived exosomes combined with curcumin overcomes the limitations in clinical application of curcumin, such as poor bioavailability and stability, and offers a novel nanotherapeutic strategy to treat HIRI clinically. Full article

Dietary lipid sources critically influence growth, health, and muscle quality in Chinese mitten crab (Eriocheir sinensis), yet how high oleic acid diet (HOA) regulates intramuscular nutrient deposition remains unclear. Here, a 10-week feeding trial compared isonitrogenous and isoenergetic diets, in which soybean oil was replaced with high-oleic peanut oil. HOA significantly improved weight gain, specific growth rate, and protein efficiency ratio, without affecting survival, hepatosomatic index (HSI), or gonadosomatic index (GSI). HOA enhanced antioxidant capacity by increasing catalase activity and reducing malondialdehyde, while key non-specific immune enzymes were unchanged. In muscle, HOA did not increase intramuscular oleic acid (OA) content but reduced linoleic acid and upregulated genes involved in fatty acid transport and β-oxidation. HOA also shifted free amino acids (higher glutamate and lysine; lower proline) without significant transcriptional upregulation of the mechanistic target of rapamycin (mTOR) pathway or changing total protein. Multi-omics analyses indicated altered nucleotide/purine pathways and pronounced glycerophospholipid remodeling, identifying discriminatory lipid species. Overall, oleic-acid-rich lipids promote growth and antioxidant defense while reprogramming muscle lipid metabolism, supporting their targeted use to optimize crab muscle quality. Full article

Background/Objectives: Astragalus root is a classical qi-tonifying traditional Chinese medicine that has demonstrated potential therapeutic efficacy in type 2 diabetes mellitus (T2DM) and non-alcoholic fatty liver disease (NAFLD). However, the precise mechanisms underlying its effects on the comorbidity of these two disorders remain unclear. This study investigated the molecular mechanisms by which Astragalus root ameliorated T2DM-NAFLD comorbidity. Methods: Network pharmacology, molecular docking, molecular dynamics simulation, and in vitro experiments were employed to elucidate the potential roles and mechanisms of Astragalus root in the management of T2DM-NAFLD comorbidity. Results: A total of 25 bioactive constituents and 152 corresponding targets associated with Astragalus root were identified. PPI network analysis revealed the top ten core candidate targets, among which six possessed suitable crystal structures for molecular docking, including interleukin-6 (IL-6), threonine-protein kinase 1(AKT1), transcription factor AP-1(JUN), tumor necrosis factor (TNF), cysteine-dependent aspartate-specific protease 3 (CASP3), and estrogen Receptor 1(ESR1). Kyoto encyclopedia of genes and genomes (KEGG) analysis further identified the phosphatidylinositol 3-kinase (PI3K)-AKT as the most significantly enriched pathway. Molecular docking validated the potential binding modes of formononetin to the six core targets, a finding that was further confirmed by molecular dynamics simulations, which proved the stability of the resulting complexes. In vitro experiments demonstrated that formononetin obviously decreased lipid droplet accumulation, downregulated total cholesterol (TC) and triglyceride (TG) levels, suppressed the expression of TNF-α, IL-6, and interleukin-1β (IL-1β), decreased reactive oxygen species (ROS) and malondialdehyde (MDA) levels, and enhanced glutathione (GSH) content and superoxide dismutase (SOD) activity. These therapeutic effects were achieved through inhibition of protein expression within the PI3K/AKT/mechanistic target of rapamycin (mTOR) signaling pathway. Conclusions: This study determined the potential therapeutic targets and underlying mechanisms of formononetin derived from Astragalus root in the T2DM-NAFLD management, thereby providing a scientific basis for its clinical application. Full article

Understanding the genetic basis of growth and moltism in silkworm (Bombyx mori) is essential for improving silk production efficiency and elucidating the mechanisms underlying developmental plasticity. Thus, this study aimed to establish a collection of 20 representative B. mori core strains and perform integrative genomic analyses combining genome-wide association studies (GWASs) and population-specific variant detection. A total of 5,293,831 high-confidence single-nucleotide variants (SNVs) were identified across the population, and GWAS revealed significant associations between specific genetic loci and four growth-related traits: larval weight at day 7 of the fifth instar, pupal weight, cocoon weight, and cocoon layer weight. Among these, two missense variants within the Cycb gene were significantly correlated with increased body weight at the late fifth instar stage, suggesting a potential role for this isoform in regulating cell-cycle-driven tissue expansion during rapid larval growth. Moreover, a population-based comparison identified 2803 trimolter-specific missense SNVs in 1440 genes, of which 109 were functionally annotated. Notably, homozygous variants were detected in key developmental regulators, such as MET1 and TOR1, implying potential alterations in juvenile hormone signaling and nutrient-dependent growth pathways that may contribute to the dominant trimolter phenotype. Although experimental validation remains necessary, these findings provide a genomic framework for understanding the molecular mechanisms underlying moltism variation and offer valuable resources for future silkworm genetic improvement. Full article