Excessive mechanical stress is a main cause of intervertebral disc degeneration (IDD). However, the specific mechanism remains unclear. We established in vivo and in vitro models to investigate the role of cytoskeletal proteins in excessive mechanical stress-induced NP cell pyroptosis and IDD. The expression level of Vimentin was decreased in degenerated NP cells induced by excessive mechanical stress. Knockdown of Vimentin promoted NP cell pyroptosis and IDD in rats, whereas Vimentin overexpression significantly alleviated excessive mechanical stress-induced NP cell pyroptosis and degeneration. Further mechanistic studies revealed that Vimentin ameliorated mitochondrial dysfunction triggered by excessive mechanical stress through PINK1-Parkin-dependent mitophagy, thereby attenuating NP cell pyroptosis and degeneration. Co-immunoprecipitation-mass spectrometry analysis suggested an interaction between Itgb1 and Vimentin, which was validated by Co-immunoprecipitation assays. Itgb1 enhanced Vimentin protein stability via the ubiquitin-proteasome pathway and inhibited mechanical stress-mediated Vimentin degradation. Subsequent experiments confirmed that Itgb1 reduced Vimentin ubiquitination and degradation by blocking the binding of MNAT1 to Vimentin. Itgb1 ameliorated excessive mechanical stress-induced NP cell pyroptosis and degeneration via Vimentin. Restoring Vimentin function through gene overexpression effectively inhibited NP cell pyroptosis and delayed the progression of IDD in rats. In summary, this study reveals a mechanotransduction pathway from mechanical stress sensing to cellular functional regulation in IDD, providing novel insights into the pathological mechanisms underlying IDD. Moreover, this study demonstrates that Vimentin exerts a significant protective effect against excessive mechanical stress-induced NP cell pyroptosis and IDD, offering a potential therapeutic target for the clinical management of IDD.
Lung squamous cell carcinoma (LUSC) is characterized by high malignancy, strong invasive and metastatic potential, and poor overall prognosis, and the core molecular mechanisms underlying its malignant progression remain to be further elucidated. This study aimed to investigate the effects of Contactin-1 (CNTN-1) on the malignant biological behaviors of tumor cells and its underlying molecular mechanisms in LUSC. A CNTN-1-knockdown NCI-H520 LUSC cell line was established. Transcriptome sequencing was performed to analyze differentially expressed genes (DEGs) and conduct functional enrichment analysis. The effects of CNTN-1 on the malignant biological behaviors of LUSC cells were investigated in vitro using quantitative real-time polymerase chain reaction (qRT-PCR), western blot (WB), Cell Counting Kit-8 (CCK-8), Transwell and other assays. Polydatin was used as an endoplasmic reticulum stress (ERS) inducer, and a nude mouse xenograft model was constructed to validate the regulatory effects of CNTN-1 and ERS on LUSC cells growth both in vivo and in vitro. A total of 5,961 DEGs were identified by transcriptome sequencing, which were mainly enriched in cellular immune response, cytokine-cytokine receptor interaction, phosphatidylinositol 3-kinase-protein kinase B (PI3K-Akt) and other signaling pathways. In vitro experiments showed that the proliferation, migration and invasion of LUSC cells were inhibited, cell apoptosis was promoted, and cell cycle arrest was induced by CNTN-1 knockdown. Meanwhile, the expression of CHOP, BiP, N-cadherin, Vimentin, XBP-1s was downregulated, the expression of E-cadherin was upregulated, and the activation of PI3K-Akt signaling pathway was suppressed by CNTN-1 knockdown. The inhibitory effects of CNTN-1 knockdown on the epithelial-mesenchymal transition (EMT) process, PI3K-Akt signaling pathway activation and malignant cellular phenotypes were partially reversed by polydatin. CNTN-1 promotes the malignant biological behaviors of LUSC cells by positively regulating ERS, as well as activating the process of EMT and the PI3K-Akt signaling pathway.
In idiopathic pulmonary fibrosis (IPF), damage to alveolar type II (AT2) cells and their aberrant reprogramming are regarded as key events in disease progression. Apart from anesthetic exposure, the peri-anesthetic period is also characterized by additional stressors, such as mechanical ventilation-induced stretch. Here, peri-anesthetic stress-related genes (PSRGs) were treated as a literature-derived, biologically relevant prior gene framework to prioritize candidate genes associated with AT2 state remodeling in IPF. Single-cell and bulk transcriptomic datasets from IPF and control lungs were analyzed. PSRGs were intersected with concordant differentially expressed genes to identify candidate hub genes, which were further prioritized using an integrated machine-learning framework. IGFBP2 expression in AT2-related states was analyzed in GSE128033 and validated in GSE135893, with complementary pseudo-bulk, correlation, covariate, CellChat, scTenifoldKnk, and DrugCLIP analyses. Two AT2 states, mature and injury/transitional, were identified. IGFBP2 was prioritized for state-focused analysis and showed reproducible enrichment in injury/transitional AT2 cells in both GSE128033 and GSE135893. IGFBP2 expression also increased along pseudotime, whereas COL1A1 did not show a clear trajectory-related pattern. Cell-cell communication analysis suggested prominent microenvironmental interactions involving injury/transitional AT2 cells. Computational perturbation analysis further implicated epithelial secretory and mucosal defense-related programs within the IGFBP2-associated network. IGFBP2 was identified as a reproducibly enriched candidate in injury/transitional AT2 cells across discovery and validation cohorts. These findings suggest that IGFBP2 may be associated with AT2 state remodeling and altered epithelial microenvironmental communication in IPF, although functional and protein level validation remains necessary.
Stress conditions elicit the formation of different kinds of stress granules (SGs). Although male germ cells are particularly sensitive to heat stress, the composition of heat-induced SGs in the testis remains poorly characterized. Here, we show that ATXN2 is a main component of heat-induced SGs in male germ cells and identify a unique population of ATXN2-positive SGs in leptotene and zygotene spermatocytes lacking classical SG markers. The terminal nucleotidyltransferase 5A (TENT5A) is a cytoplasmic poly(A) polymerase that extends the poly(A) tails of mRNAs. Tent5a mRNA expression increases when somatic and germ cells are exposed to 42 °C, but not upon exposure to other stressors. In vitro, TENT5A extends the poly(A) tail of Atxn2 transcripts, stabilizing them while repressing their translation. In heat-stressed testes, TENT5A depletion increases ATXN2-positive granules and reduces apoptosis in late pachytene spermatocytes. Thus, enhanced stress resilience in Tent5a-depleted male germ cells preserves spermatogenesis and rescues fertility following heat exposure.
Standardized and reproducible cell models are key to replace animal testing in toxicology. The composition of culture medium is a major, yet frequently undercontrolled, determinant of cell state in vitro. For decades, fetal bovine serum (FBS) has been routinely incorporated into liver cell culture. Its undefined and lot-to-lot variable composition can, however, confound cell identity and experimental reproducibility. Chemically defined media (CDM) represent an alternative approach that can improve standardization, but the consequences of transitioning from FBS-supplemented media (FBS-SM) to CDM remain insufficiently characterized in hepatic models, particularly with respect to metabolic and detoxification programs that govern xenobiotic metabolism and hepatotoxicity readouts. Here, we systematically assessed how replacing FBS-SM with CDM remodels transcriptomic profiles in two widely used human hepatic cell lines (HepaRG and HuH7 cells) and compared the results to that obtained from primary human hepatocytes (PHH). Global transcriptomic analyses indicated that cell type was the primary driver of variance, whereas medium induced a model-dependent secondary effect. Functional interpretation showed preferential enhancement of xenobiotic metabolism and transport-associated programs in HepaRG cells, while HuH7 cells response was dominated by lipid/sterol homeostasis and stress-linked processes. Benchmarking against PHH based on hepatic identity and detoxification gene panels further supported improved PHH alignment for HepaRG cells under CDM compared to cultures with FBS-SM, with limited improvement for HuH7 cells. Collectively, these findings show that medium effects must be interpreted in the context of cell line identity and indicate that HepaRG cells cultured in CDM provide a more PHH-like transcriptomic background for in vitro studies of xenobiotic metabolism and hepatotoxicity-related readouts than HuH7 cells.
Cartilage repair in osteoarthritis is limited not only by structural defects in articular cartilage but also by the chronic redox and immune dysregulation in the microenvironment. Acellular cartilage matrix (ACM) replicates tissue-specific extracellular matrix (ECM) characteristics, but lacks the capacity to counteract oxidative stress and secondary inflammation in the tissue microenvironment. In this research, we incorporated tannic acid (TA) into methacrylated ACM (ACMMA) to develop a dynamic dual-crosslinked network bioink for cartilage organoid constructs. TA remodeled precursor assembly behavior, altered the interfacial charge, and promoted the formation of a denser hydrogel microstructure. ACMMA-TA exhibited enhanced chondrogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) equivalent to ACMMA. However, under oxidative stress, it significantly reduced intracellular and mitochondrial reactive oxygen species (ROS) levels, preserved mitochondrial membrane potential, suppressed the expression of pro-inflammatory cytokines, and promoted anti-inflammatory macrophage polarization. Transcriptomic analysis of ACMMA-TA based organoid constructs revealed enhanced ECM preservation and glutathione metabolism, along with the inhibition of IL-17 and NF-κB signaling. In a rat articular cartilage defect model, the ACMMA and ACMMA-TA groups showed comparable moderate improvement, while TA functionalized cell-laden organoid constructs achieved the highest ICRS scores with hyaline-like cartilage formation. These results indicate that TA functions as a conditional microenvironment stabilizer, suggesting that biomaterial design for cartilage repair may prioritize maintaining cell function under pathological stress over structural optimization or robust chondrogenic capacity alone.
Systematically characterized the ARF family in Triticeae revealed its evolutionary expansion patterns and validated that TaARF4.1 acts as a repressor enhancing salt/alkali tolerance potentially by regulating cell wall metabolism and ROS homeostasis. Auxin response factors (ARFs) are core transcription factor families mediating auxin signaling, which not only regulate plant growth and development but also bridge the trade-off between growth and stress adaptation. However, their roles in responding to abiotic stresses-particularly salt/alkali stress, a major constraint to global wheat production-remain poorly understood in wheat (Triticum aestivum). To address this, we integrated evolutionary genomics, multi-tissue expression profiling, and functional validation across 10 Poaceae species (including wheat, rice, maize, and other Triticeae crops) to systematically identify stress-regulatory wheat ARFs (TaARFs). We identified 349 ARF members and reconstructed the evolutionary trajectory across 10 species, clarified orthologous relationships between TaARFs and rice ARFs (OsARFs), and revealed that TaARF expansion is driven by two mechanisms: ancient whole-genome duplication (WGD) conserving core ARF functions and recent gene duplication burst (RBGD) generating Triticeae-specific duplicates (e.g., TaARF4.1/4.2). GO enrichment and stress-induced expression analyses highlighted Group IV repressor ARFs (TaARF4.1/4.2/9) as candidate regulators of abiotic stress responses. Transcriptome integration across salt/alkali-treated wheat leaves and roots identified stably stress-responsive TaARFs, while functional assays confirmed TaARF4.1, as a repressor ARF with the whole-cell localization, was associated with key genes involved in stress signaling, cell wall metabolism, and reactive oxygen species (ROS) homeostasis. This study demonstrates that underutilized genome evolution data aids gene mining in complex crop genomes, providing novel genetic resources for wheat salt/alkali tolerance breeding and insights into auxin-mediated stress adaptation mechanisms.
Cellular and intramitochondrial calcium (Ca2+) overload, along with mitochondrial dysfunction, play a critical role in contrast-induced renal tubular epithelial cell injury. This study aims to clarify the role and mechanism of the Mitochondrial Calcium Uniporter (MCU) and mitochondrial dynamics in this process. Part 1: An in vitro CI-AKI model was established using human renal proximal tubular epithelial (HK-2) cells. The experimental design comprised a normal control group and iohexol-treated groups (100 mg I/mL) incubated for 4, 8, and 12 h, respectively. Part 2: To investigate the role of MCU, HK-2 cells were assigned to four conditions: normal control, iohexol alone, MCU inhibitor + iohexol group, and MCU agonist + iohexol group. We evaluated tubular cell injury and mitochondrial impairment, focusing on MCU expression, mitochondrial dynamics and Ca2+ loading, to clarify the molecular mechanisms. Iohexol induced time-dependent cellular injury and apoptosis, accompanied by MCU upregulation, elevated intramitochondrial Ca2+ and mitochondrial dynamic imbalance. It also triggered mitochondrial membrane potential (ΔΨm) loss and mitochondrial reactive oxygen species (mtROS) accumulation. MCU inhibition with Ru360 enhanced cell viability, reduced apoptosis, improved mitochondrial function, suppressed Dynamin-related protein 1 (DRP1), reduced mitochondrial Ca2+, preserved ΔΨm and decreased mtROS. Conversely, MCU activation with spermine exacerbated the injury. Contrast-induced upregulation of MCU exacerbates intramitochondrial Ca2+ overload, preferentially promotes mitochondrial fission, resulting in the dissipation of ΔΨm and aggravated oxidative stress, which ultimately leads to cellular injury and apoptosis. Critically, inhibition of MCU conferred a protective effect against contrast-induced injury.
Cisplatin resistance in ovarian cancer, particularly in ovarian clear cell carcinoma, involves intricate mechanisms related to oxidative stress, deoxyribonucleic acid repair, and cell cycle. Resistance in ovarian clear cell carcinoma is associated with genes, such as pyruvate dehydrogenase kinase-2 and hepatocyte nuclear factor 1 beta, which enhance glycolysis and reduce reactive oxygen species that would normally facilitate cisplatin induced deoxyribonucleic acid damage. Additionally, nuclear factor erythroid 2-related factor-2 and superoxide dismutase-2 play pivotal roles in regulating reactive oxygen species levels, thereby safeguarding ovarian clear cell carcinoma cells from oxidative damage. The postsynaptic density protein 95/discs large/zona occludens-1 (PDZ)-binding motif-angiopoietin-like 4 nicotinamide adenine dinucleotide phosphate oxidase-2 axis plays a crucial role in modulating ferroptosis, presenting potential therapeutic targets. A deeper understanding of these mechanisms offers promising strategies to overcome cisplatin resistance, particularly in ovarian clear cell carcinoma. These insights could pave the way for targetted therapies aimed at improving ovarian cancer outcomes, especially for ovarian clear cell carcinoma subtypes.
Although plants are exposed to many environmental stressors (heat, drought, salinity, and pathogen), they survive by rapidly reprogramming their gene expression. Recent findings show that many regulatory mechanisms are maintained within liquid-liquid phase separation (LLPS) formed biomolecular condensates, instead of maintaining these mechanisms within membrane-bound organelles. LLPS has been shown to exist in plant cells; however, the integration of LLPS with functional stress adaptations and gene regulations is still unclear from the studies that have been published thus far. In this review, we discuss recent research that demonstrates how these biomolecular condensates act as dynamic regulatory centers by linking environmental stress perception to transcriptional and post-transcriptional regulation of genes in plants. We describe the biophysical principles that govern the occurrence of LLPS in a plant cellular environment and provide an overview of how both abiotic (e.g., drought, heat) and biotic (i.e., pathogens) stressors initiate the LLPS and remodel nuclear and cytosolic condensate structures. The focus of this work will be on the effects of stress-induced changes (both qualitatively and quantitatively) in the condensate composition and material properties on transcription factor activity (either as an activator or repressor) and the organization of chromatin, RNA stability, and selective translation. We will also discuss post-translational modifications (PTMs) that modulate condensate dynamics and allow for reversibility. Collectively, these findings suggest that LLPS likely contributes significantly to gene regulation and stress adaptation in plants, although the degree of mechanistic validation varies among different condensate systems.
Diabetes mellitus is a metabolic disorder characterized by persistent hyperglycaemia that may impair male reproductive function. Mesenchymal stem/stromal cell-derived conditioned medium (MSC-CM) has emerged as a promising cell-free therapeutic approach for diabetes-associated complications. This study investigated the effects of CM obtained from MSCs cultured under normoxic (N-CM) or deferoxamine (DFX)-induced hypoxia-mimetic conditions (DFX-CM) on diabetes-related testicular dysfunction in streptozotocin (STZ)-induced diabetic rats. Diabetes was induced in Sprague Dawley rats using a single intraperitoneal injection of STZ (55 mg/kg). Diabetic rats received intraperitoneal administration of N-CM or DFX-CM for 3 weeks. Serum reproductive hormones were analysed by ELISA. Histological and histomorphometric evaluations were performed using haematoxylin and eosin staining, while ultrastructural alterations were examined by transmission electron microscopy (TEM). Oxidative stress markers and antioxidant enzyme activities were also assessed in testicular tissue. Diabetes reduced serum follicle-stimulating hormone (FSH), gonadotropin-releasing hormone, and luteinizing hormone levels, although only FSH showed a significant decrease. Histological analyses revealed mild impairment of spermatogenesis in diabetic rats without significant morphometric alterations. TEM demonstrated marked ultrastructural abnormalities in diabetic testes, including Sertoli cell degeneration and disrupted spermatogenic cell morphology. Both CM treatments attenuated these alterations, with improved ultrastructural organization observed particularly in Sertoli cells. Diabetes also induced oxidative stress, evidenced by reduced catalase and superoxide dismutase activities and elevated malondialdehyde and H2O2 levels. N-CM treatment showed the strongest antioxidant effects. These findings suggest that MSC-CM, particularly N-CM, may alleviate diabetes-induced testicular damage by restoring oxidative balance and preserving seminiferous tubule ultrastructure.
Therapy-resistant cancers remain largely incurable because malignant cells acquire metabolic adaptations that sustain survival under chronic cytotoxic and oxidative stress. One such adaptation is constitutively enhanced macropinocytosis, enabling aggressive cancer cells to scavenge extracellular nutrients and maintain redox homeostasis. Here, we introduce a macropinocytosis-exploiting polymer-metal strategy that converts this metabolic dependency into a lethal vulnerability. We developed PPS02, a polyaspartic acid sodium salt-based metal complex that is preferentially internalized by cancer cells via macropinocytosis, while remaining largely excluded from normal epithelial cells. This cancer-preferential uptake enables intracellular delivery of selenomethionine and ferrous iron, resulting in intracellular H2O2 accumulation, mitochondrial reactive oxygen species overload, and activation of necroptotic cell death. Macropinocytic activity was significantly elevated in patient-derived metastatic colorectal cancer cells but remained minimal in normal colonic epithelial cells, demonstrating pronounced cancer selectivity. Accordingly, PPS02 exhibited negligible cytotoxicity toward normal colonic epithelial cells while effectively suppressing the viability of both nonmetastatic and platinum-resistant metastatic colorectal cancer cells. In patient-derived xenograft models, PPS02 induced sustained tumor regression without overt systemic toxicity under the experimental conditions, whereas cisplatin failed to control metastatic tumors and caused significant adverse effects. Collectively, these findings support macropinocytosis-driven redox imbalance as a therapeutically exploitable vulnerability and demonstrate a polymer-metal platform that preferentially induces necroptosis in drug-resistant cancer while sparing normal tissues.
Introduction. During the coronavirus disease 2019 (COVID-19) pandemic, the cases of mucormycosis increased substantially, with rhino-orbito-cerebral form linked to uncontrolled diabetes being the predominant manifestation. Several risk factors were implicated in the emergence of COVID-19-associated mucormycosis (CAM), including inappropriate corticosteroid usage and COVID-19-associated glycaemic imbalance.Gap statement. Some clinical and epidemiological studies associated the usage of zinc supplements with the occurrence of CAM, but experimental evidence remains limited.Aim. This study aimed to elucidate the impact of zinc enrichment on Rhizopus arrhizus, the predominant causative agent of mucormycosis.Methodology. The effect of zinc supplementation (5 to 150 µM) on fungal growth, metabolic activity, antifungal susceptibility and biofilm formation, along with cell-wall (Congo red), oxidative (hydrogen peroxide) and osmotic (sodium chloride) stress was evaluated in Roswell Park Memorial Institute -1640 medium. Morphological changes were visualized by scanning electron microscopy. Gene expression and intracellular zinc levels were determined by RNA sequencing and inductively coupled plasma mass spectrometry, respectively. The cytotoxic potential of R. arrhizus pre-cultured with and without zinc supplementation was assessed in the human embryonic kidney 293 cell line.Results. Zinc supplementation promoted R. arrhizus growth in a concentration-dependent manner, with the effect being particularly pronounced under less-favourable conditions, such as alkaline conditions resembling the nasal pH of diabetics. The results further suggested a zinc-specific effect: supplementation with another trace element (copper) suppressed R. arrhizus growth, and the zinc chelator (1,10-phenanthroline) dose-dependently abrogated the zinc-induced growth enhancement. Exposure to zinc increased the metabolic activity, and partly alleviated cell-wall and oxidative stress. Susceptibility to amphotericin B and posaconazole was unchanged. Zinc-supplemented cultures over-expressed multiple genes, notably those associated with respiratory electron transport chain, ergosterol biosynthesis, chitosan production, oxidative stress response, mucoricin, high-affinity iron permease, iron transport multi-copper oxidase and ferric-reductase-like protein. R. arrhizus cytotoxicity was also significantly enhanced upon pre-culturing with zinc supplementation. Additionally, zinc augmented the growth/metabolism of several other Mucorales but not Aspergillus fumigatus and Candida albicans.Conclusion. Zinc supplementation promotes mucoralean growth, increases cytotoxic potential and enhances the expression of key virulence factors, including mucoricin and iron transporters. The findings contribute experimental evidence supporting the proposed association of zinc over-availability with the emergence of CAM.
Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by profound cognitive decline, wherein chronic neuroinflammation plays a pivotal pathogenic role. Central to this inflammatory milieu is pyroptosis, a highly inflammatory form of programmed lytic cell death mediated by gasdermin proteins. This comprehensive review provides an in-depth synthesis of the cellular and molecular mechanisms underlying pyroptosis in AD. We detail the distinct roles of microglia as primary initiators responding to amyloid-beta (Aβ) and tau aggregates, alongside the specific vulnerabilities of neurons facing oxidative stress, astrocytes impacting metabolic support, and endothelial cells whose pyroptotic death contributes directly to blood-brain barrier disruption. At the molecular level, the priming and activation of the NLRP3 and NLRP1 inflammasomes by diverse triggers, including classical markers like Aβ, environmental neurotoxicants and metabolic stressors, converge on caspase-1 and caspase-8 activation. This cascade culminates in gasdermin D (GSDMD) and gasdermin E (GSDME) pore formation, leading to cellular lysis and the massive release of pro-inflammatory cytokines such as IL-1β and IL-18. Furthermore, this paper explores the emerging and critical concept of PANoptosis, highlighting the intricate crosstalk between pyroptosis, apoptosis, and necroptosis within PANoptosome complexes triggered by mitochondrial dysfunction. We evaluate current and prospective therapeutic strategies, ranging from multi-target natural and traditional herbal remedies to advanced nanomedicine, synthetic small molecules, and epigenetic gene therapies. By integrating insights from blood-based pyroptosis-associated molecular signatures and advanced targeted drug delivery systems, we emphasize the critical need for personalized, multi-targeted approaches to successfully harness pyroptosis modulation in the clinical management and treatment of AD.
This study aims to synthesize Simarouba glauca seed-mediated silver nanoparticles (Sg-AgNPs) through an eco-friendly approach and to evaluate their antioxidant, anti-inflammatory, and anticancer efficacy against HepG2 hepatocellular carcinoma cells. To characterize biosynthesized Sg-AgNPs' optical properties, functional groups, crystallinity, morphology, particle size, and elemental composition, UV-Visible spectroscopy, FT-IR, XRD, SEM, TEM, and EDX were used. Nanoparticles exhibiting a surface plasmon resonance peak at 430 nm and TEM showing 15-60 nm spherical particles. Studies showed considerable antioxidant, anti-inflammatory, and cytotoxic actions against HepG2 cells, with an IC₅₀ value of 42.7 µg/mL. Sg-AgNPs limit cancer cell growth via oxidative stress and apoptosis. These results demonstrate Simarouba glauca-mediated AgNPs as a durable and physiologically beneficial nanoplatform for hepatocellular carcinoma therapy.
By integrating a three-winding coupled inductor (TWCI) with voltage multiplier cells, this study proposes a quadratic DC-DC converter that achieves ultra-high voltage gain while maintaining continuous input current and a common ground. The proposed coupled-inductor topology is specifically engineered to minimize both voltage and current stresses across all circuit components, thereby enhancing overall performance and enabling potential cost reductions. Enhanced design flexibility is a key feature of the proposed configuration, particularly because the secondary winding of the TWCI operates in a semi-trans-inverse manner, allowing high voltage gains to be realized even with a very low turns ratio. Regenerative passive clamp circuits are incorporated to recover the leakage energy of the TWCI and to limit voltage stresses on the active switches, which are driven with simultaneous switching patterns. The converter's vertical structure further alleviates semiconductor voltage stress, while intrinsic current sharing between the TWCI and the input inductor substantially reduces power dissipation in the main power components. Additionally, turn-off switching losses of both active switches are minimized via a quasi-resonant cell. The paper presents a comprehensive steady-state analysis, detailed power loss evaluation, a comparative study with existing topologies, and key design guidelines. All theoretical contributions are conclusively validated through experimental results obtained from a 200 W hardware prototype, converting a 25 V input to a 400 V output.
Osteoarthritis (OA) is a degenerative joint disorder marked by chronic inflammation, extracellular matrix (ECM) breakdown, and subchondral bone remodeling, ultimately leading to loss of cartilage integrity and joint function. Hyaluronic acid (HA), a key component of synovial fluid, contributes to joint lubrication and has been implicated in the regulation of inflammatory and anabolic processes. High-molecular-weight (HMW) HA (> 1 MDa) is reported to exert anti-inflammatory and matrix-preserving effects; however, its role in multicellular systems remains incompletely understood. In this study, we investigated the effects of HMW HA using an in vitro chondrocyte-osteoclast co-culture model designed to reflect key features of the osteoarthritic microenvironment. Bone marrow-derived mesenchymal stem cells were differentiated into chondrocytes, while RAW 264.7 macrophages were induced into osteoclast-like cells using M-CSF and RANKL. Cells were co-cultured at a 1:1 ratio and stimulated with lipopolysaccharide (LPS; 1 µg/mL) to induce inflammatory stress, followed by HA treatment (50-500 µg/mL) for 24-48 h. Cell viability, morphology, and TRAP staining were assessed. Expression of inflammatory and matrix-associated markers was analysed by Western blot, qPCR, and ELISA. Cell-cycle distribution and DNA integrity were evaluated using flow cytometry and agarose gel electrophoresis. LPS exposure reduced metabolic activity, altered morphology, and was associated with increased expression of NF-κB-related inflammatory markers and elevated expression of IL-1β, TNF-α, MMP-13, and ADAMTS-5, alongside reduced COL2A1 and ACAN levels. HA treatment improved metabolic activity and preserved cellular morphology in a concentration-dependent manner, with the most pronounced effects observed at 200-500 µg/mL. HA-treated cultures showed lower levels of inflammatory and catabolic markers together with increased expression of ECM-associated genes. In addition, HA treatment was associated with a more balanced cell-cycle profile and reduced DNA fragmentation. HMW HA was associated with coordinated modulation of inflammatory and matrix-related markers in an LPS-induced co-culture system. These findings suggest that HA may contribute to maintaining cellular homeostasis under inflammatory conditions in vitro. Further studies are needed to clarify the underlying mechanisms and translational relevance.
Hepatocellular carcinoma (HCC), a malignancy with high global mortality, exhibits a close association with mitochondrial dynamic imbalance. Mitochondria maintain cellular homeostasis through a dynamic equilibrium of fission and fusion, and dysregulation of this process can trigger metabolic reprogramming, oxidative stress, and dysregulation of multiple modes of cell death, ultimately driving HCC progression. This review systematically elucidates the molecular mechanisms and therapeutic targets associated with mitochondrial dynamic imbalance in HCC. It begins by analyzing the structure and functional characteristics of mitochondria, outlining the universal impact of their fission-fusion regulatory network on cancer biology. Subsequently, it focuses on HCC-specific pathological mechanisms, revealing how mitochondrial dynamic imbalance reshapes the tumor microenvironment via the Warburg effect, lipotoxicity, and reactive oxygen species (ROS) burst. A key emphasis is placed on the role of mitochondrial dysfunction in regulating multiple modes of cell death, including apoptosis, ferroptosis, pyroptosis, autophagy, and the emerging mechanism of cuproptosis. The link between cuproptosis and mitochondrial copper accumulation, lipoylated protein aggregation, and metabolic collapse provides a novel perspective for HCC therapy. Finally, the review critically evaluates therapeutic strategies targeting mitochondrial dynamics, discussing the translational potential of DRP1 inhibitors (e.g., Mdivi-1), mitophagy activators (e.g., rapamycin), and copper chelators (e.g., tetrathiomolybdate). Future directions, such as mitochondrial-targeted nanodelivery systems and multi-target combination therapies, are also explored. This comprehensive review aims to provide a theoretical foundation and innovative insights for understanding the pathogenesis and advancing precision therapy in HCC.
The buildup of toxic aggregates formed by the amyloid-β peptide 1-42 (Aβ42) is a central process in Alzheimer's disease (AD) pathology. The peptide's self-assembly and toxicity are highly dependent on its primary amino acid sequence and can be altered by modifying key residues. Specifically, the single amino acid substitutions A30W, K28A, and M35C can reduce the aggregation and toxicity of the Aβ42 peptide. In this study, we further evaluated the effects of these mutations in a C6 rat glioma cell line and in the Caenorhabditis elegans strains CL2006 and CL4176, which express muscular Aβ42 as an in vivo model. Our results showed that the A30W, K28A, and M35C substitutions reduce apoptosis induction in cell culture, in contrast to the WT Aβ42 peptide. In C. elegans, the three variants extended the lifespan of CL2006 worms by reducing fibrillar aggregates or altering aging, whereas the M35C peptide delayed the paralysis of CL4176 worms. Additionally, the substitutions altered oxidative stress and autophagy in control worms. Taken together, these results suggest that the A30W, K28A, and M35C substitutions reduce Aβ42 toxicity in cell culture and in C. elegans and could protect the nematode against Aβ42 toxicity.
XBP1s, a key downstream molecule of endoplasmic reticulum stress (ERS), is widely involved in processes such as proliferation, invasion, and apoptosis in cancer. However, the role and underlying mechanism of XBP1s in colorectal cancer (CRC) remain poorly understood. We hypothesize that XBP1s plays a critical role in promoting CRC proliferation through the regulation of autophagy. Therefore, this study aims to investigate the expression, biological functions, and underlying mechanisms of XBP1s in colorectal cancer, opening up new directions for targeted tumor therapy. Based on The Cancer Genome Atlas (TCGA) database, the expression of XBP1 in pan-cancer tissues and CRC tissues was analyzed. Western blotting (WB) and immunohistochemistry (IHC) were used to validate the protein expression level of XBP1s in clinical CRC tissues, and its correlation with clinicopathological characteristics and patient prognosis was assessed. The effects of XBP1s on CRC cells were examined using in vitro cell experiments. Furthermore, bioinformatics analyses, including Gene Ontology (GO) functional annotation and gene set enrichment analysis (GSEA) pathway enrichment, were employed to predict downstream pathways associated with XBP1s, which were subsequently validated through follow-up experiments. Therefore, this study aims to investigate the expression, biological functions, and underlying mechanisms of XBP1s in colorectal cancer, opening up new directions for targeted tumor therapy. The expression of XBP1s was significantly higher in CRC tissues compared to normal tissues and was significantly associated with poor prognosis in CRC patients. Knockdown of XBP1s expression ex vivo markedly inhibited CRC cell proliferation and promoted apoptosis. GO and GSEA enrichment analyses revealed a close association between XBP1 and the autophagy signaling pathway. Consequently, by utilizing inhibitors and establishing an ERS model, it was demonstrated that XBP1s might promote CRC growth and proliferation by activating autophagy. Our findings indicate that interference with XBP1s expression can inhibit the malignant proliferation of CRC by suppressing the autophagy signaling pathway. Targeting XBP1s may represent a novel therapeutic strategy for the diagnosis and treatment of CRC patients.