Search Results (32,150)

Mechanosensitive ion channels such as OSCA1.2 enable cells to sense and respond to mechanical forces by translating membrane tension into ionic flux. While lipid rearrangement in the inter-subunit cleft has been proposed as a key activation mechanism, the contributions of other domains to OSCA gating remain unresolved. Here, we combined the genetic encoding of the photoactivatable crosslinker p-benzoyl-L-phenylalanine (BzF) with functional Ca²⁺ imaging and molecular dynamics simulations to dissect the roles of specific residues in OSCA1.2 gating. Targeted UV-induced crosslinking at positions F22, H236, and R343 locked the channel in a non-conducting state, indicating their functional relevance. Structural analysis revealed that these residues are strategically positioned: F22 interacts with lipids near the activation gate, H236 lines the lipid-filled cavity, and R343 forms cross-subunit contacts. Together, these results support a model in which mechanical gating involves a distributed network of residues across multiple channel regions, allosterically converging on the activation gate. This study expands our understanding of mechanotransduction by revealing how distant structural elements contribute to force sensing in OSCA channels. Full article

Growth hormone (GH) signaling has been implicated in tumor progression and therapy resistance across multiple cancer types, yet its role in bladder cancer remains largely unexplored. In this study, we investigated the impact of GH and its receptor (GHR) on therapy resistance and disease progression in urothelial carcinoma (UC) through integrated transcriptomic and in vitro analyses. Transcriptomic profiling of The Cancer Genome Atlas bladder cancer cohort revealed that high tumoral GHR expression was associated with differential upregulation of genes involved in drug efflux, epithelial-to-mesenchymal transition (EMT), and extracellular matrix (ECM) remodeling. Notably, elevated GHR levels correlated with significantly reduced overall survival in patients with UC. In parallel, in vitro experiments demonstrated that GH promotes chemoresistance in UC cell lines via upregulation of ATP-binding cassette-containing (ABC) transporters and activation of EMT. GH also modulated ECM-remodeling-associated genes in a chemotherapy-dependent manner, including matrix metalloproteinases and tissue inhibitors of metalloproteinases. Importantly, these effects were abrogated by Pegvisomant, a GHR antagonist, indicating the functional relevance of GH/GHR signaling in the mediation of these phenotypes. Collectively, our findings support a mechanistic role for GH signaling in driving therapy resistance and tumor aggressiveness in bladder cancer and suggest GHR antagonism as a potential therapeutic strategy to improve treatment outcomes. Full article

Unconventional food plants (UFPs) are increasingly valued for their nutritional composition and bioactive potential. This study proposes a comprehensive characterization of the chemical and bioactive properties of Pereskia aculeata Miller (Cactaceae) (PA); Xanthosoma sagittifolium (L.) Schott (Araceae) (XS); Stachys byzantina K. Koch (Lamiaceae) (SB); and inflorescences from three cultivars of Musa acuminata (Musaceae) var. Dwarf Cavendish, var. BRS Platina, and var. BRS Conquista (MAD, MAP, and MAC), including the assessment of physical, nutritional, phytochemical, and biological parameters. Notably, detailed phenolic profiles were established for these species, many of which are poorly documented in the literature. XS was characterized by a unique abundance of C-glycosylated flavones, especially apigenin and luteolin derivatives, rarely described for this species. SB exhibited high levels of phenylethanoid glycosides, particularly verbascoside and its isomers (up to 21.32 mg/g extract), while PA was rich in O-glycosylated flavonols such as quercetin, kaempferol, and isorhamnetin derivatives. Nutritionally, XS had the highest protein content (16.3 g/100 g dw), while SB showed remarkable dietary fiber content (59.8 g/100 g). Banana inflorescences presented high fiber (up to 66.5 g/100 g) and lipid levels (up to 7.35 g/100 g). Regarding bioactivity, PA showed the highest DPPH radical scavenging activity (95.21%) and SB the highest reducing power in the FRAP assay (4085.90 µM TE/g). Cellular antioxidant activity exceeded 2000% in most samples, except for SB. Cytotoxic and anti-inflammatory activities were generally low, with only SB showing moderate effects against Caco-2 and AGS cell lines. SB and PA demonstrated the strongest antimicrobial activity, particularly against Yersinia enterocolitica, methicillin-resistant Staphylococcus aureus (MRSA), and Enterococcus faecalis, with minimum inhibitory concentrations ranging from 0.156 to 0.625 mg/mL. Linear discriminant analysis revealed distinctive chemical patterns among the species, with organic acids (e.g., oxalic up to 7.53 g/100 g) and fatty acids (e.g., linolenic acid up to 52.38%) as key discriminant variables. Overall, the study underscores the nutritional and functional relevance of these underutilized plants and contributes rare quantitative data to the scientific literature regarding their phenolic signatures. Full article

Non-small cell lung cancer (NSCLC) is a predominant form of lung cancer that is often diagnosed at an advanced metastatic stage. The processes of cancer cell migration and invasion involve epithelial-to-mesenchymal transition (EMT), which is crucial for metastasis. Targeting cancer aggressiveness with effective plant compounds has gained attention as a potential adjuvant therapy. Eurycomanone (ECN), a bioactive quassinoid found in the root of Eurycoma longifolia Jack, has demonstrated anti-cancer activity against various carcinoma cell lines, including human NSCLC cells. This study aimed to investigate the in vitro effects of ECN on the migration and invasion of human NSCLC cells and to elucidate the mechanisms by which ECN modulates the EMT in these cells. Non-toxic doses (≤IC20) of ECN were determined using the MTT assay on two human NSCLC cell lines: A549 and Calu-1. The results from wound healing and transwell migration assays indicated that ECN significantly suppressed the migration of both TGF-β1-induced A549 and Calu-1 cells. ECN exhibited a strong anti-invasive effect, as its non-toxic doses significantly suppressed the TGF-β1-induced invasion of NSCLC cells through Matrigel and decreased the secretion of MMP-2 from these cancer cells. Furthermore, ECN could affect the TGF-β1-induced EMT process in various ways in NSCLC cells. In TGF-β1-induced A549 cells, ECN significantly restored the expression of E-cadherin by inhibiting the Akt signaling pathway. Conversely, in Calu-1, ECN reduced the aggressive phenotype by decreasing the expression of the mesenchymal protein N-cadherin and inhibiting the TGF-β1/Smad pathway. In conclusion, this study demonstrated the anti-invasive activity of eurycomanone from E. longifolia Jack in human NSCLC cells and provided insights into its mechanism of action by suppressing the effects of TGF-β1 signaling on the EMT program. These findings offer scientific evidence to support the potential of ECN as an alternative therapy for metastatic NSCLC. Full article

According to the World Health Organization (WHO), a healthy lifestyle is defined as a way of living that lowers the risk of becoming seriously ill or dying prematurely. Physical activity, as a well-known contributor to overall health, plays a vital role in supporting such a lifestyle. Exercise induces complex molecular responses that mediate both acute metabolic stress and long-term physiological adaptations. FGF21 (fibroblast growth factor 21) and GDF15 (growth differentiation factor 15) are recognized as metabolic stress markers, while their receptors play critical roles in cellular signaling. However, the differential gene expression patterns of these molecules in trained and untrained individuals following exhaustive exercise remain poorly understood. This study aimed to examine the transcriptional and protein-level responses in trained and untrained individuals performed a treadmill maximal exercise test to voluntary exhaustion. Blood samples were collected at six time points (pre-exercise, immediately post-exercise, and 0.5 h, 6 h, 24 h, and 48 h post-exercise). Gene expression of FGF21, GDF15, FGFR1 (fibroblast growth factor receptors), FGFR3, FGFR4, KLB (β-klotho), and GFRAL (glial cell line-derived neurotrophic factor receptor alpha-like) was analyzed using RT-qPCR, while plasma protein levels of FGF21 and GDF15 were quantified via ELISA. The results obtained were statistically analyzed by using Shapiro–Wilk, Mann–Whitney U, and Wilcoxon tests in Statistica 13 software. Untrained individuals demonstrated significant post-exercise upregulation of FGFR3, FGFR4, KLB, and GFRAL. FGF21 and GDF15 protein levels were consistently lower in trained individuals (p < 0.01), with no significant correlations between gene and protein expression. Trained individuals showed more stable expression of genes, while untrained individuals exhibited transient upregulation of genes after exercise. Full article

Valvular hemangiomas are uncommon vascular anomalies that appear on the surface of heart valves. They can cause an array of non-specific symptoms and are consequently rarely diagnosed, with only 31 such cases (including the present one) reported to date in the literature; the present case is the first report of an arteriovenous hemangioma with a tricuspid localization. During the preoperative echocardiographic examination for a ventricular septal defect, a mass was incidentally discovered on the tricuspid valve of a 9-month-old infant. The involved leaflet was surgically removed and sent to the pathology department for analysis and subsequently diagnosed as an arteriovenous hemangioma. The patient recovered well, with no local tumor recurrence or other complications. The microscopic examination showed multiple blood vessels which stained positive for the endothelial markers CD31 and CD34 and which did not express D2-40, normally found in lymphatic endothelia. Surprisingly, endothelial cells lining the vessels also showed positivity for SMA, a mesenchymal cell marker, indicating a possible involvement of endothelial-to-mesenchymal transition and its opposite process, mesenchymal-to-endothelial transition, in the pathogenesis of these vascular anomalies. Full article

In epithelial cells, nonmuscle myosin-2B (NM2B) shows a cortical localization and is tethered to tight junctions (TJs) and adherens junctions (AJs) by the junctional adaptor proteins cingulin and paracingulin. MDCK cells knock-out (KO) for cingulin show decreased apical membrane cortex stiffness and decreased TJ membrane tortuosity, and the rescue of these phenotypes requires the myosin-binding region of cingulin. Here, we investigated whether NM2B contributes to these phenotypes independently of cingulin by generating and characterizing clonal lines of MDCK cells KO for NM2B. The loss of NM2B resulted in decreased stiffness and increased fluidity of the apical cortex and reduced accumulation of E-cadherin and phalloidin-labeled actin filaments at junctions but had no significant effect on TJ membrane tortuosity. Fluorescence recovery after photobleaching (FRAP) showed that the KO of NM2B increased the dynamics of the TJ scaffold protein ZO-1, correlating with decreased ZO-1 accumulation at TJs. Finally, the KO of NM2B increased cell size in cells grown both in 2D and 3D but did not alter lumen morphogenesis of cysts. These results extend our understanding of the functions of NM2B by describing its role in the regulation of the mechanical properties of the apical membrane cortex and cell size and validate our model about the role of cingulin–NM2B interaction in the regulation of ZO-1 dynamics. Full article

Gingival inflammation compromises the integrity of the gingival epithelium and the underlying tissues, highlighting the need for adjuvant therapies with immunomodulatory and healing properties. Casearia sylvestris, a medicinal plant known as guaçatonga, is traditionally used to treat inflammatory lesions. This study aimed to investigate the effects of C. sylvestris on the synthesis of pro- and anti-inflammatory, proteolytic, and antioxidant molecules and on wound healing in epithelial cells. A human telomerase-immortalized gingival keratinocyte cell line (TIGKs) was used, and cells were exposed to Escherichia coli lipopolysaccharide (LPS) in the presence and absence of C. sylvestris extract, its diterpene-concentrated fraction, and its clerodane diterpene casearin J for 24 h and 48 h. Gene expression and protein synthesis were analyzed by RT-qPCR and ELISA, respectively. Nitric oxide (NO) and NF-κB activation were analyzed by Griess reaction and immunofluorescence, respectively. Additionally, cell viability was evaluated by alamarBlue^® assay, and an automated scratch assay was used for wound healing. LPS significantly increased the expression of cytokines (TNF-α, IL-1β, IL-6, IL-8, IL-10, IL-17), proteases (MMP-1 and MMP-13), iNOS as well as NO synthesis, and triggered NF-κB nuclear translocation. It also reduced IL-4 expression, cell viability, and cellular wound repopulation. Treatment with C. sylvestris derivatives significantly abrogated all aforementioned LPS-induced effects by 80–100%. Furthermore, even at higher concentrations, C. sylvestris did not affect cell viability, thus proving the safety of its derivatives. C. sylvestris exerts anti-inflammatory, antiproteolytic, and antioxidant effects on gingival keratinocytes, highlighting its potential as a valuable adjunct in the prevention and treatment of periodontal diseases. Full article

A novel ruthenium(II) complex, [RuCl₂(η⁶-p-cymene)(bph-κN)] (1), was synthesized and structurally characterized using FTIR and NMR spectroscopy. Density functional theory (DFT) calculations supported the proposed geometry and allowed for comparative analysis of experimental and theoretical spectroscopic data. The interaction of complex 1 with human serum albumin (HSA) and calf thymus DNA was investigated through fluorescence quenching experiments, revealing spontaneous binding driven primarily by hydrophobic interactions. The thermodynamic parameters indicated mixed quenching mechanisms in both protein and DNA systems. Ethidium bromide displacement assays and molecular docking simulations confirmed DNA intercalation as the dominant binding mode, with a Gibbs free binding energy of −34.1 kJ mol⁻¹. Antioxidant activity, assessed by EPR spectroscopy, demonstrated effective scavenging of hydroxyl and ascorbyl radicals. In vitro cytotoxicity assays against A375, MDA-MB-231, MIA PaCa-2, and SW480 cancer cell lines revealed selective activity, with pancreatic and colorectal cells showing the highest sensitivity. QTAIM analysis provided insight into metal–ligand bonding characteristics and intramolecular stabilization. These findings highlight the potential of 1 as a promising candidate for further development as an anticancer agent, particularly against multidrug-resistant tumors. Full article

Plant flowers are recognized as a rich source of bioactive phenolic compounds. In this study, for the first time, the recovery of antioxidant phenolic compounds from Cytisus striatus flowers (CF) was optimized using microwave-assisted extraction (MAE). The variables (% of ethanol, temperature, and time) were studied using a response surface methodology (RSM). Extraction efficiency was assessed by total phenol content, total flavonoid content, and the antioxidant capacity through DPPH, ABTS, FRAP, and CUPRAC assays. Additionally, cytotoxicity and anti-inflammatory properties were evaluated in different cell lines. The optimal extraction conditions (87.6% ethanol, 160.8 °C and 8.76 min) yielded extracts rich in phenolics (85.9 mg GAE/g CF) and flavonoids (120.3 mg RE/g CF), with strong antioxidant capacity. LC-MS/MS analysis identified 27 phenolic compounds, including chrysin, apigenin, and quercetin derivatives. Cytotoxicity tests showed that CF extract maintained high viability (>80%) in human embryonic kidney (HEK293T) and human lung adenocarcinoma (A549) cells up to 2000 µg/mL, indicating low cytotoxicity. The anti-inflammatory potential was evidenced by a decrease in IL-1β levels and an increase in IL-10 cytokine production in LPS-stimulated macrophages. These results highlight the great potential of CF as a promising bioresource to obtain value-added compounds for the development of functional foods, nutraceuticals, and cosmetic products. Full article

Belzutifan is a hypoxia-inducible factor-2α (HIF-2α) inhibitor that received FDA approval in 2021 for treating cancers resulting from von Hippel-Lindau (VHL) disease, including clear cell renal cell carcinoma (ccRCC), followed by approval in 2023 for sporadic ccRCC that has progressed through multiple lines of therapy. HIF-2α is a promising drug target, as VHL is commonly inactivated in ccRCC, which results in HIF-2α-mediated signaling that is considered central to tumorigenesis. Belzutifan has demonstrated efficacy in clinical trials in the first-line and subsequent line settings, and in combination with tyrosine kinase inhibitors. Despite being overall well tolerated, belzutifan has a distinct safety profile because of its unique mechanism of action. Anemia was the most common adverse event observed in clinical trials and is considered an on-target effect. Hypoxia is also frequently observed and commonly results in dose reductions, treatment discontinuation, and supplemental oxygen use. This review summarizes the rates of hypoxia seen in clinical trials of belzutifan in ccRCC. As the cause of hypoxia is not well understood, this review also discusses possible mechanisms of hypoxia based on preclinical studies of the HIF pathway and HIF-2α inhibitors. Finally, this review proposes monitoring and management recommendations for clinicians prescribing belzutifan to ccRCC patients. Full article

Background/Objectives: P-glycoprotein (P-gp), an ATP-binding cassette (ABC) transporter, plays a key role in multidrug resistance by actively exporting chemotherapeutic agents and xenobiotics from cells. Overexpression of P-gp significantly reduces intracellular drug accumulation and compromises treatment efficacy. Despite extensive research, clinically approved P-gp inhibitors remain elusive due to toxicity, poor specificity, and limited efficacy. This study investigates DMH1, a selective type I BMP receptor inhibitor, as a novel P-gp inhibitor. Methods: DMH1 cytotoxicity was assessed in P-gp-overexpressing (PC3-TxR, K562/Dox) and P-gp-deficient (PC3) cell lines using MTT assays. P-gp inhibition was evaluated using calcein AM retention and daunorubicin (DNR) accumulation assays. Kinetic analysis determined DMH1’s effect on P-gp-mediated transport (Vmax and Km). ATPase activity assays were performed to assess DMH1’s impact on ATP hydrolysis. Preliminary molecular docking (CB-Dock2) was used to predict DMH1’s binding site on the human P-gp structure (PDB ID: 6QEX). Results: DMH1 showed no cytotoxicity in P-gp-overexpressing or deficient cells. It significantly enhanced intracellular accumulation of Calcein AM and DNR, indicating effective inhibition of P-gp function. Kinetic data revealed that DMH1 reduced Vmax without affecting Km, consistent with noncompetitive, allosteric inhibition. DMH1 also inhibited ATPase activity in a dose-dependent manner. Docking analysis suggested DMH1 may bind to an allosteric site in the transmembrane domain, potentially stabilizing the inward-facing conformation. Conclusions: DMH1 is a promising noncompetitive, allosteric P-gp inhibitor that enhances intracellular drug retention without cytotoxicity, supporting its potential as a lead compound to overcome multidrug resistance and improve chemotherapeutic efficacy. Full article

Gaucher disease (GD) is an autosomal recessive disorder caused by the deficient activity of the lysosomal enzyme glucocerebrosidase (GCase). Although enzyme replacement therapy (ERT) remains the standard of care for non-neuropathic GD patients, its high cost significantly limits accessibility. To enhance production efficiency, we developed a lentiviral system encoding a codon-optimized GCase gene driven by the human elongation factor 1a (hEF1α) promoter for stable production in human cell lines. A functional lentiviral vector, LV_EF1α_GBA_Opt, was generated at a titer of 7.88 × 10⁸ LV particles/mL as determined by qPCR. Six transduction cycles were performed at a multiplicity of infection of 30–50. The transduced heterogeneous human cell population showed GCase-specific activity of 307.5 ± 53.49 nmol/mg protein/h, which represents a 3.21-fold increase compared to wild-type 293FT cells (95.58 ± 16.5 nmol/mg protein/h). Following single-cell cloning, two clones showed specific activity of 763.8 ± 135.1 and 752.0 ± 152.1 nmol/mg/h (clones 15 and 16, respectively). These results show that codon optimization, a lentiviral delivery system, and clonal selection together enable the establishment of stable human cell lines capable of producing high levels of biologically active, synthetic recombinant GCase in vitro. Further studies are warranted for the functional validation in GD patient-derived fibroblasts and animal models. Full article

The tumor microenvironment plays an important role in tumor incidence, metastasis, and chemotherapy resistance. Novel therapeutic strategies targeting the tumor microenvironment have become a research focus in the field of biomedicine. In this study, we developed a smart small-molecule probe, TZ2, featuring pH/GSH dual-responsive characteristics. TZ2 exhibits a unique pH-dependent reaction mechanism: GSH is preferentially covalently modified with maleimide groups in acidic microenvironments (pH < 7), while specifically activating nucleophilic substitutions under alkaline conditions (pH > 7). It is worth noting that TZ2 effectively eliminates intracellular glutathione (GSH) in a time and concentration-dependent manner, demonstrating significant GSH depletion ability in various tumor cell lines. Pharmacodynamic studies have shown that TZ2 not only inhibits the cell cycle by regulating the expression of cell cycle-related proteins, but also effectively suppresses the cloning ability of cancer cells. Furthermore, TZ2 significantly increases the sensitivity of drug-resistant cancer cells to cisplatin. By integrating microenvironment modulation, real-time monitoring, and synergistic therapy, TZ2 provides a novel molecular tool and theoretical basis for tumor theranostics integration. Full article

The histone H2A variant H2AZ plays pivotal roles in shaping chromatin architecture and regulating gene expression. We recently identified H2AZ.2 in histone H2A lysine 119 ubiquitination (H2AK119ub)-enriched nucleosomes, but it is not known whether its highly related isoform H2AZ.1 also regulates this modification. In this study, we employed isoform-specific epitope-tagged knock-in mouse embryonic stem cell (ESC) lines to dissect the roles of each isoform in Polycomb Repressive Complex 1 (PRC1)-mediated H2AK119ub. Our results show that H2AZ.1 and H2AZ.2 share highly overlapping genomic binding profiles, both co-localizing extensively with H2AK119ub-enriched loci. The knockdown of either isoform led to reduced H2AK119ub levels; however, the two isoforms appear to function through distinct mechanisms. H2AZ.1 facilitates the recruitment of Ring1B, the catalytic subunit of PRC1, thereby promoting the deposition of H2AK119ub. In contrast, H2AZ.2 does not significantly affect Ring1B recruitment but instead functions as a structural component that stabilizes H2AK119ub-modified nucleosomes. In vitro ubiquitination assays indicate that H2AZ.1-containing nucleosomes serve as more efficient substrates for PRC1-mediated ubiquitination compared to those containing H2AZ.2. Thus, these findings define the distinct mechanisms of the two H2AZ variants in regulated PRC1-mediated H2AK119 ubiquitination and highlight a functional division of labor in epigenetic regulation. Full article