Search Results (2,601)

Background/Objectives: Osteoarthritis is a chronic joint disorder involving the progressive breakdown of articular cartilage, which leads to joint pain and impaired mobility. The present study investigated the effects of curcuminoids phospholipid (CP) on osteoarthritis progression, assessed its cartilage-protective effects, and elucidated the underlying mechanisms. Methods: Male Sprague–Dawley rats were randomly allocated to six experimental groups. One group received an intra-articular saline injection as the normal control (NC), while the remaining five groups were injected with monosodium iodoacetate (MIA) and consisted of an MIA control group (MC), a positive control group treated with celecoxib (PC, 3 mg/kg), and three groups treated with CP (31.25, 62.5, or 125 mg/kg). Results: Compared with the MC group, CP administration significantly improved pain-related behavior, as assessed by weight-bearing measurements. Micro-computed tomography and histological analyses demonstrated that CP administration mitigated subchondral bone erosion and preserved cartilage integrity. Additionally, the CP treatment significantly reduced markers associated with cartilage degradation, including matrix metalloproteinases and cartilage oligomeric matrix proteins; downregulated the expression of matrix-degrading enzymes; and restored aggrecan expression. Serum levels of inflammatory mediators, including nitric oxide; prostaglandin E₂; C-reactive protein; and pro-inflammatory cytokines, including interleukin (IL)-6, tumor necrosis factor (TNF)-α, and IL-1β, were reduced following CP administration. Furthermore, CP decreased the activation of nuclear factor kappa B (NF-κB) signaling. Conclusions: These findings suggest that CP may be a promising functional agent for osteoarthritis, demonstrating beneficial effects on pain-related outcomes and cartilage integrity, potentially mediated by its anti-inflammatory activity. Full article

Background: Conventional urothelial carcinoma (UC) requires accurate risk stratification, particularly differentiation between non-muscle-invasive (NMIBC) and muscle-invasive bladder cancer (MIBC) and between low- and high-grade tumors. This study evaluated immunohistochemical (IHC) expression of vitamin D receptor (VDR), β-catenin, and Ki-67 index in Egyptian patients with conventional UC. Methods: A cross-sectional study was conducted on 58 archived conventional UC cases diagnosed in 2023 at Al-Azhar University Hospitals. VDR positivity was defined as ≥10% cytoplasmic and/or nuclear tumor cell staining. Membranous β-catenin was considered preserved when >80% of tumor cell membranes were stained; otherwise, it was reduced. Nuclear β-catenin was considered positive when ≥5% of tumor nuclei were stained. Ki-67 was categorized as high using a ≥30% cutoff. Associations with grade, muscle invasion status, and lymphovascular invasion (LVI) were analyzed. Results: Mean age was 65.3 ± 9.3 years; 86.2% were males; 51.7% were MIBC. Compared with NMIBC, MIBC was significantly associated with high grade, non-papillary architecture, LVI, and high Ki-67. VDR positivity was detected in 82.7% of cases and showed no significant association with grade, muscle invasion, or LVI. Preserved membranous β-catenin was seen in 34.5% and was significantly associated with tumor grade but not with muscle invasion or LVI; nuclear β-catenin was absent. High Ki-67 (60.3%) was significantly associated with high grade and MIBC, with no association with age, sex, or LVI. Conclusions: In Egyptian conventional UC, Ki-67 was a significant marker for aggressive clinicopathologic features, while VDR lacked discriminatory associations and β-catenin findings were mainly grade-related. Full article

Background: Hepatic ischemia–reperfusion (I/R) injury induces systemic oxidative stress and inflammatory responses that may lead to remote lung injury. This study investigated whether taxifolin attenuates hepatic I/R-induced lung damage and examined the involvement of the nuclear factor-κB (NF-κB) and high-mobility group box-1 (HMGB1) signaling axis. Methods: Twenty-eight male Wistar rats were divided into four groups (n = 7): control, taxifolin, hepatic I/R, and taxifolin+I/R. Serum oxidative stress markers (malondialdehyde [MDA], interleukin [IL]-6, total antioxidant/oxidant status [TAS/TOS]) and wet-to-dry lung weight ratio were measured. Lung tissues were evaluated histopathologically and immunohistochemically for NF-κB and HMGB1 expression. Bioinformatics pathway enrichment and molecular docking analyses were also performed. Results: Hepatic I/R significantly increased serum MDA, IL-6, and TOS levels and decreased TAS (p < 0.05). Severe lung injury was observed in the hepatic I/R group (median score: 11), whereas taxifolin pretreatment significantly reduced the injury score (median score: 5, p < 0.001). NF-κB and HMGB1 expression were markedly elevated following hepatic I/R and significantly decreased with taxifolin treatment (p < 0.05). A strong positive correlation was found between NF-κB and HMGB1 expression (r = 0.82, p < 0.001). Pathway enrichment analysis indicated involvement of Toll-like receptor (TLR)-related inflammatory signaling, and docking analysis demonstrated favorable binding of taxifolin to TLR4 and NF-κB p65. Conclusion: Taxifolin attenuated hepatic I/R-induced lung injury by reducing oxidative stress and suppressing HMGB1–TLR4–NF-κB-mediated inflammatory signaling. Full article

ZmSIG2A is a nuclear-encoded plastid sigma factor 2A in maize (Zea mays L.) that is essential for plastid gene transcription and chloroplast biogenesis. As a key regulator of chloroplast development and function, ZmSIG2A may also contribute to the coordination of plant growth and environmental adaptation; however, its roles in root development and stress responses remain largely unclear. We compared two ZmSIG2A mutants, eal1-1 (hypomorphic) and ems110 (nonsense). eal1-1 had increased root number and longer roots, while ems110 had normal root number but shorter roots and failed to mature. The zmsig2a^Val480del transcript was upregulated in eal1-1, and the root-promoting effect of OsSIG2A in rice suggests a conserved role in monocot root growth. DAP-seq indicated that zmsig2a^Val480del targets are involved in metabolism, transport, signaling, and antioxidants, with Chr4 peak clustering near multiple LRR-RLKs, suggesting a ZmSIG2A–LRR-RLK module in root development and stress integration. Physiologically, eal1-1 showed increased antioxidant enzyme activities and reduced MDA, indicating enhanced ROS scavenging, while ems110 exhibited decreased enzyme activities and elevated MDA, indicating compromised ROS detoxification. Upstream, Y1H and dual-luciferase assays demonstrated that the Mediator subunit ZmMed31 positively regulates transcription from the ZmSIG2A promoter. Given Mediator’s role in bridging transcription factors and the core transcriptional machinery, ZmMed31 likely links hormone-responsive transcription factors to the ZmSIG2A regulatory network. Collectively, we propose a stress-responsive ZmMed31–ZmSIG2A–LRR-RLK module that underpins maize root development and drought adaptation, offering mechanistic insight and potential targets for stress-resilient breeding. Full article

Mitogen-activated protein kinase kinase kinases (MAPKKKs) play important roles in plant responses to abiotic stresses; however, the function of SiMAPKKK17 in mediating drought tolerance in foxtail millet remains unclear. In this study, the expression pattern, subcellular localization, and biological function of SiMAPKKK17 were investigated to clarify its role in the drought stress response. Tissue expression analysis showed that SiMAPKKK17 was expressed across developmental stages and in multiple organs, with the highest transcript level observed at the booting stage and comparatively higher expression in vegetative tissues, including roots, stems, and leaves. Subcellular localization analysis demonstrated that SiMAPKKK17 was localized to both the plasma membrane and the nucleus, suggesting potential involvement in membrane-associated signal transduction and nuclear regulatory processes. To evaluate its function, foxtail millet lines overexpressing SiMAPKKK17 were generated and subjected to drought stress. Compared with wild-type plants, the overexpression lines exhibited enhanced drought tolerance, as indicated by greener and more upright upper leaves, higher aboveground fresh weight, greater plant height, and larger leaf area under drought conditions. Transcriptome analysis of OE4 and WT plants under drought stress identified 3919 upregulated genes and 2965 downregulated genes in OE4 compared with WT. These differentially expressed genes were mainly enriched in chloroplast-related cellular components, as well as biological processes and metabolic pathways related to cellular amide metabolism, ion transport, carbon metabolism, photosynthesis, carbon fixation, purine metabolism, and amino acid biosynthesis. Taken together, these results indicate that SiMAPKKK17 acts as a positive regulator of drought tolerance in foxtail millet, potentially through modulation of photosynthesis- and metabolism-related pathways. This study provides evidence for the molecular mechanisms underlying drought tolerance in foxtail millet and identifies SiMAPKKK17 as a promising candidate gene for the development of drought-resistant cultivars. Full article

The ATRX gene encodes an SWI/SNF-type chromatin remodeling protein that is critical for proper development of the mammalian central nervous system and musculoskeletal system. While significant progress has been made in understanding the molecular functions of the full-length (FL) ATRX protein, there is still very little known about its conserved alternative spliceoform, ATRXt. ATRXt is a truncated isoform of ATRX which lacks the entire SWI/SNF domain due to the retention of intron 10, which results in the in-frame addition of 61 unique amino acids (exon 10a) at its C-terminus. Here, we demonstrate that ATRXt accounts for 5–20% of total ATRX protein levels, while showing tissue- and differentiation-specific changes in expression levels compared to its full-length counterpart. ATRXt shows enriched localization at H3K9me3-positive heterochromatin but not at PML-nuclear bodies, while physically interacting with the known FL-ATRX protein partners, DAXX and HP1α. Exon 10a can target a GFP-fusion protein to the nucleolus, but removal of exon 10a from ATRXt does not prevent nucleolar localization. Finally, re-introducing ATRXt into the ATRX-negative U2OS cell line reduced rRNA transcription and severely hampered cell growth, similar to previous studies using FL-ATRX. Our study highlights that ATRXt has many of the same properties as FL-ATRX, suggesting that some roles of ATRX do not require remodeling activity, while highlighting the need to distinguish ATRXt’s functions from those of the full-length protein. Full article

Mitogen-activated protein kinase kinase kinase 1 (MAP3K1) possesses dual enzymatic functions, i.e., kinase and E3 ubiquitin ligase activities, orchestrating proliferation, survival, apoptosis, DNA damage response, and immune modulation. Recent genomic and mechanistic studies have revealed MAP3K1’s paradoxical, context-dependent roles as both an oncogene and a tumor suppressor. We discuss MAP3K1’s multidomain architecture, featuring an N-terminal RING and PHD domain (E3 ligase activity), a TOG domain (microtubule dynamics), and a C-terminal kinase domain, enabling the integration of c-jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (p38 MAPK), extracellular signal-regulated kinase (ERK), and nuclear factor kappa B (NF-κB) signaling pathways. MAP3K1 functions as a molecular switch balancing survival and apoptosis, with caspase-3 cleavage at Asp878 activating pro-apoptotic JNK/p38 signaling. Genomic analyses across >35 cancer types reveal MAP3K1 alterations at frequencies of <1–14%, highest in breast and endometrial cancers. These alterations show tissue specificity: loss-of-function mutations predominate in hormone receptor-positive breast cancer with a favorable prognosis, whereas gain-of-function mutations in melanoma activate oncogenic ERK signaling. MAP3K1 mutations predict response to mitogen-activated protein kinase kinase (MEK) and phosphoinositide 3-kinase (PI3K) inhibitors, with mutant cancers showing higher MEK inhibitor response than wild-type tumors. Despite substantial progress, critical gaps remain regarding MAP3K1’s E3 ligase substrates, context-dependent activity determinants, and therapeutic strategies. Addressing these through inhibitor development, biomarker validation, and mechanistic studies will accelerate potential clinical translation of MAP3K1 biology. Full article

Growth, reproduction, and survival are fundamental biological priorities that animals balance by evaluating dietary cues. Cholesterol occupies a unique position among nutrients, serving both as a structural component of cellular membranes and as a precursor for steroid hormones, yet its regulation differs fundamentally across taxa. In mammals, cholesterol availability is buffered by endogenous synthesis and post-ingestive metabolic control. In contrast, insects have evolutionarily lost sterol biosynthesis and are therefore sterol auxotrophs that rely entirely on dietary sources. Here, we synthesize current understanding of cholesterol biology in Drosophila melanogaster, with a focus on sterol auxotrophy, life-stage–specific allocation, and endocrine and lifespan outcomes in a comparative framework. We highlight cholesterol not only as a metabolic substrate but also as a sensory-encoded nutrient that shapes feeding behavior. We further examine how lipophorin (Lpp)-mediated transport, Niemann–Pick type C proteins, ATP-binding cassette transporters, and the nuclear receptor DHR96 coordinate systemic sterol distribution and endocrine output in the absence of endogenous synthesis. By integrating these mechanisms across development, we illustrate how cholesterol availability governs larval growth, ecdysteroid production, adult reproduction, neural function, and lifespan through coupled endocrine and nutrient-signaling networks. This review positions cholesterol as a multifunctional signal linking sensory perception, metabolic regulation, and life-history strategy in sterol-auxotrophic insects, offering a framework for understanding how evolutionary loss of biosynthetic capacity reshapes nutrient sensing and homeostatic control. Full article

Radiation-responsive promoters represent a functionally distinct class of transcriptional regulatory elements that translate genotoxic stress signals into quantifiable gene expression outputs. These promoters occupy a unique mechanistic position within the broader radiation biomarker landscape: rather than directly measuring molecular damage products, they report the cellular interpretation of radiation-induced stress through coordinated gene regulatory networks. This review provides a systematic analysis of five major classes of radiation-responsive promoters—microRNA (miRNA) promoters, tRNA-derived small RNA (tsRNA) promoters, acute-phase protein gene promoters, DNA repair gene promoters, and long non-coding RNA (lncRNA) promoters—with emphasis on their regulatory logic, dose-response characteristics, and current evidence for clinical deployment. We further describe four complementary screening strategies: homology-based conservation analysis, functional genomics and transcriptomics, epigenetic modification profiling, and synthetic biology promoter engineering. Applications spanning biosensor development, biological dosimetry, treatment response prediction, and radiation-guided gene therapy are evaluated within a two-track framework that distinguishes biomarker-oriented applications (Track A) from tool-oriented reporter gene systems (Track B). Critical appraisal of current limitations—including insufficient clinical-grade validation, absence of standardized dose-response curves, and reproducibility deficits—is integrated throughout. Future priorities include multi-center prospective validation studies, FAIR-compliant data infrastructure, AI-driven multi-omics integration, and point-of-care detection platforms. Radiation-responsive promoter biology holds significant potential for advancing precision radiotherapy and nuclear emergency medical response, contingent upon systematic closure of the current evidence gap relative to established gold-standard cytogenetic methods. Full article

Whether apoptotic cell death occurs in cerebellar Purkinje cells following transient global ischemia remains unclear. Histologic, immunofluorescent and ultramicroscopic methods were used to assess ischemic outcomes in rats. A pilot study using fluorescence labeling [TUNEL-caspase 3-activated peptide (C3AP)-DAPI] revealed key apoptotic characteristics including nuclear TUNEL-positive, nuclear membrane blebs (NMBs), and cytoplasmic C3AP-positive structures, in addition to transport of TUNEL-positive round structures into cytoplasm and projections in ischemic Purkinje cells but not in controls 4 days after ischemia. A formal follow-up study confirmed that 8% of Purkinje cells 4 days following ischemia exhibited TUNEL-positivity and/or NMBs, while Purkinje cells in controls did not. TUNEL-positive Purkinje cells displayed reduced intensity of Calbindin D28K-ifl/MitoTracker (living cell markers) labeling as compared to controls (p < 0.01). Ultramicroscopic evidence of apoptosis included mitochondrial fragmentation and loss in addition to NMBs and cytosolic deposit of nuclear autophagosomes. Interestingly, 71% of the Purkinje cells exhibited autophagy activity after ischemia. Ultramicroscopic characteristics of survival in ischemic Purkinje cells included a centrally located nucleus, no significant chromatin condensation, stable nuclear and intact cytoplasmic membranes, and normal peripheral spacing of the Purkinje cells. In conclusion, four days after transient global ischemia, cerebellar Purkinje cells exhibited both apoptotic and survival characteristics. Further research warrants investigation of the underlying mechanisms. Full article

During eukaryotes evolution, mitochondrial DNA (mtDNA) fragments integrate into nuclear genomes, forming nuclear mitochondrial DNA sequences (Numts). Tortricidae (Lepidoptera), a species-rich and economically critical family, lacks systematic characterization of Numts, which hinders reliable molecular research. Here, we systematically characterized Numts in 27 Tortricidae species spanning two subfamilies via genome download, mitochondrial genome annotation, and Numt identification and characterization. With each species’ mtDNA as query, Numt identification was performed with an E-value threshold of 10⁻⁴ and a sequence similarity cut-off of >60%, with a minimum length of 50 bp to exclude spurious hits. Results showed that all species contained Numts, with copy numbers varying drastically (9–208). Numt numbers positively correlated with nuclear genome length, but not mitochondrial genome length. Numts insertion flanking regions had significantly higher AT content than nuclear genome, indicating the insertion preference for AT-rich regions. Numts were predominantly derived from the mitochondrial cox1 gene, highlighting the risk of co-amplification when cox1 is used as a DNA barcode for species identification or phylogenetic studies. This study represents a systematic charaterizition of copy number, length distribution, insertion sequence preferences, and mitochondrial gene origins of Numts in Tortricidae, offering valuable references for refining molecular systematics, comparative genomics, and pest management in Tortricidae and related lepidopteran groups. Full article

PRAME (Preferentially Expressed Antigen in Melanoma) is increasingly used as an immunohistochemical marker in the evaluation of melanocytic lesions; however, its expression in benign melanocytic proliferations remains incompletely characterized. This study investigated PRAME expression in melanoacanthomas, with particular emphasis on its relationship with ultraviolet exposure and chronic solar damage. A consecutive series of melanoacanthomas was retrospectively analyzed. Melanocytes were identified and quantified using SOX10 immunohistochemistry, while PRAME-positive melanocytes were counted and graded semiquantitatively according to nuclear staining intensity. PRAME expression was correlated with lesion site (photoexposed versus non-photoexposed skin) and with the degree of solar elastosis. Eighty-four cases were evaluated, of which 25 (29.8%) showed at least focal PRAME positivity in melanocytes. Overall melanocytic density assessed by SOX10 did not differ significantly between photoexposed and non-photoexposed lesions. Similarly, stratification based on total PRAME-positive melanocyte counts, irrespective of staining intensity, revealed no significant association with photoexposure. In contrast, analysis restricted to melanocytes with strong nuclear PRAME expression demonstrated a significant enrichment in photoexposed lesions compared with non-photoexposed sites (p < 0.01). Moreover, high-intensity PRAME expression showed a positive association with increasing grades of solar elastosis. These findings indicate that strong PRAME expression in melanoacanthoma could be associated with chronic sun damage and may reflect non-specific, ultraviolet-related modulation rather than malignant transformation, underscoring the importance of contextual interpretation of PRAME immunohistochemistry in diagnostic practice. Full article

Background: Main risk factors associated with the development of sarcopenia (coexistence of muscle mass loss and dysfunction) are a sedentary lifestyle coupled with obesity. Associated mitochondrial dysfunction leads to energy deficits and perturbations in the balance between protein synthesis and degradation, thereby triggering muscle dysfunction or atrophy. Aside from exercise, which is challenging to implement and maintain, particularly in women, treatments for diminishing sarcopenia are scarce. The objective of the present study was to evaluate the effect of the flavanol (−)-epicatechin (EC) in a hypercaloric diet-induced obese female rat model. Muscle strength and endurance, as well as relative mitochondrial DNA content in skeletal muscle, were assessed. Methods: Female rats were fed a hypercaloric diet to induce obesity, as evidenced by increases in body weight, Lee index, and lipid profile alterations, and by abdominal fat accumulation, and to promote a sarcopenic phenotype. Functional tests of grip strength and mobility (treadmill) were performed. Mitochondrial relative content was evaluated by measuring the ratio of mtDNA/nuclear DNA, and the expression of genes related to mitochondrial biogenesis (Pgc1-α, Tfam), fusion (Mfn1 and Opa1), fission (Drp1 and Fis1), and mitophagy (Pink1 and Pkn), and function; citrate synthase and Ucp3 were also evaluated. Results: A significant decrease in mobility and strength was observed in obese female rats, accompanied by reduced mitochondrial numbers, activity, and dynamics, but not by changes in muscle size or weight. Treatment with EC induced mitochondrial biogenesis and positive changes in mitochondrial dynamics (fission and fusion) and activity, as measured indirectly by changes in citrate synthase and Ucp3 expression. Discussion: Results reinforce the potential of EC as a modulator of mitochondrial function in dysfunctional conditions associated with obesity, thereby attenuating the mechanisms underlying sarcopenia. Full article

Demodex mites are common commensals of mammalian skin, but under certain conditions, they can cause severe skin diseases. This study analyzed the presence, diversity, and phylogenetic relationships of Demodex species in two wolf subspecies from southern Europe to determine whether species-level differences exist between wild and domestic canids after thousands of years of divergence. A total of 1400 hair samples from 140 wolves were analyzed using a real-time PCR (qPCR) targeting mitochondrial 16S rRNA and nuclear 18S rRNA genes. Overall, 37.1% (52/140; 95% CI: 29.0–45.9%) of wolves were positive for Demodex DNA, with a higher prevalence in Italian (46%) than in Iberian (36%) wolves. The lip and chin areas were the most reliable sampling sites. Four Demodex species were identified in wolves: D. injai and D. canis (associated with dogs), and D. folliculorum and D. brevis (associated with humans). Co-infestations involving multiple Demodex species were recorded for the first time in wild canids. These results challenge the long-held belief of strict host specificity in Demodex mites. The discovery of Demodex species associated with both humans and dogs in wolves supports the idea that host-switching and ecological interactions have occurred throughout the evolution of canids and humans. Such cross-species transfers may have taken place during the early domestication of dogs, representing a plausible scenario compatible with our data. However, given the isolated history of the two southern wolf populations, it is more probable that these findings result from recent interspecific transmission events, likely facilitated by ecological overlap with domestic animals and human environments. Future genomic studies will be essential for clarifying the evolutionary relationships within the genus Demodex and its host associations. Full article

Chrysanthemum (Chrysanthemum morifolium) is a globally significant ornamental plant, whose growth, development, and ornamental quality are frequently impaired by salt stress. DOF (DNA-binding with one finger) family transcription factors extensively act as crucial regulators in medicating reactions to environmental pressures on plants. But their specific functions in regulating salt stress tolerance in chrysanthemum still remain largely elusive and require further investigation. Here, we isolated CmDOF2, a DOF family transcription factor from chrysanthemum, whose expression was up-regulated in chrysanthemums under salt stress. Functional analysis demonstrated that CmDOF2 functions as a nuclear-localized transcriptional activator. Comprehensive phenotypic and physiological characterization showed that heterologous expression of CmDOF2 in Arabidopsis thaliana conferred markedly increased salt stress tolerance, as reflected by higher chlorophyll, leaf relative water, and proline content; lower leaf relative electric conductivity and malondialdehyde content; and increased activities of superoxide dismutase, peroxidase, and catalase. Furthermore, qRT-PCR analyses confirmed that stable expression of CmDOF2 in Arabidopsis led to increased transcript levels of key salt-responsive genes, including stress marker genes (AtRD29A, AtRD29B), components of the SOS signaling pathway (AtSOS1, AtSOS2, AtSOS3), genes involved in osmotic adjustment (AtP5CS1, AtP5CS2), and genes encoding antioxidant enzymes (AtSOD1, AtPOD34, AtCAT3). Collectively, our data demonstrate that CmDOF2 serves as a nuclear-localized transcriptional regulator with activation activity and positively regulates salt stress tolerance by mediating the transcript levels of stress-related genes in multiple signaling pathways. Full article