Search Results (11,036)

Goat reproductive performance is a key determinant of the productivity and economic value of goat farming, especially in meat and milk production. In a previous study, to investigate the genetic basis of prolificacy, we divided goats into groups according to their consistent reproductive performance (producing either single kids or twins) over five consecutive kidding cycles, and performed whole-genome resequencing and RNA-seq analysis on their ovarian tissues. Through integrated analysis, we identified three candidate genes—IGF2BP1 (insulin-like growth factor 2 mRNA-binding protein 1), CDC25A (cell division cycle 25A), and RXFP2 (relaxin family peptide receptor 2)—as potential key regulators of reproductive capacity. Using goat ovarian granulosa cells, we systematically assessed the impact of each gene through gain- and loss-of-function experiments. Overexpression of IGF2BP1 promoted cell proliferation and suppressed apoptosis, underscoring its role in maintaining cellular viability. Conversely, its knockdown significantly impeded growth and induced cell death. Similarly, CDC25A enhanced granulosa cell proliferation, whereas its knockdown led to marked growth impairment and increased apoptosis. Proliferation was also enhanced by RXFP2 overexpression but impaired upon its knockdown, suggesting that RXFP2 is functionally important for follicular development. Collectively, these findings establish IGF2BP1, CDC25A, and RXFP2 as fundamental regulators of granulosa cell dynamics and ovarian follicular development, providing crucial functional insights and promising targets for genetic selection to enhance reproductive efficiency in goats. Full article

Retromer is an evolutionarily conserved protein complex first identified in budding yeast. It was originally described for its essential role in endosome-to-Golgi retrieval of lysosomal hydrolase receptors. Retromer is now known to mediate trafficking of many endosomal cargoes. The mammalian retromer is constituted by a core heterotrimer encoded by the vacuolar protein sorting (VPS) gene products VPS26, VPS35, and VPS29. To mediate cargo recognition and endosomal sorting into various pathways, this trimer can cooperate with phosphoinositide-binding sorting nexin family members. Defective retromer functioning has been associated with alterations in cellular homeostasis, leading to disease. To gain insights into how it may mediate these broad processes, a proteomic strategy in polarized Madin-Darby canine kidney cells was devised to identify retromer-interacting proteins. Subsequent validation of one of the candidates, i.e., cytokeratin 19, led to the unexpected finding that retromer localizes to the pericentriolar region in dividing cells and subsequently translocates to the midbody during cytokinesis. Retromer was found interacting with CK19, and its antisense depletion led to delocalization from CK19. Subcellular fractionation and live cell monitoring of depleted cells provided evidence of a role by retromer in post-metaphase progression and in epithelial cell migration, thereby connecting retromer with key processes of cellular dynamics. Full article

The immune system maintains homeostasis through coordinated innate and adaptive responses, and its imbalance increases disease susceptibility. The immunomodulatory effects of 6-methoxykaempferol (6MK), a methoxylated flavonoid found in sweet cherries, were studied in a mouse model of cyclophosphamide (CPA)-induced immunosuppression. The expression of key signaling proteins in the NF-κB and MAPK pathways was studied to explore the underlying molecular mechanisms. The Toll-like receptor-4/myeloid differentiation factor-2 receptor complex (TLR4/MD2), which can stimulate the immune response by activating these pathways, was used to study possible interactions with 6MK using docking analysis. 6MK administration significantly restored immune organ integrity (spleen up to 15.1% and thymus up to 16.8%), enhanced NK cell function (up to 43.8%), promoted T (up to 24.5%) and B cell proliferation (up to 26.4%), increased pro- and anti-inflammatory cytokine (IL-1β, IL-6, TNF-α, IL-4, IL-10, and TGF-β) levels, and elevated NO (up to 25.6%) and immunoglobulin (IgG, IgA, and IgM) concentrations. Additionally, 6MK upregulated antioxidant enzymes (CAT, HO-1, and SOD) and reactivated suppressed NF-κB and MAPK pathways. The docking-supported hypothesis, based on putative interactions and the estimated free energy of binding, suggests that 6MK possesses agonistic potential for the TLR4/MD2. Changes in the gut microbiome due to 6MK treatment, such as an increase in alpha diversity, abundance of Dorea longicatena, and the upregulation of formaldehyde-consuming pathways, may also contribute to immune enhancement. These findings show that 6MK may alleviate immunosuppression, suggesting its potential for future studies targeting immune-related diseases and conditions. Full article

Hippocalcin (HPCA), a neuron-enriched calcium-binding protein, plays a critical role in brain function, but its role in neural precursor cells remains unclear. N-methyl-D-aspartate (NMDA) receptors are calcium-permeable glutamate receptors essential for neurodevelopment and synaptic plasticity, and their function has been implicated in neurological conditions. In this study, we investigated the role of HPCA in regulating NMDA receptor expression and function in mouse hippocampal neural precursor cells (mHNPCs). HPCA knockdown significantly reduced the expression of NMDA receptor-related genes, including Grin2C, Shank1, Serpine2, and selectively attenuated NMDA-induced calcium signaling. Transcriptomic analysis identified ELAV-like RNA-binding protein 3 (Elavl3), a neuron-enriched factor associated with neuronal activity, as a downstream candidate affected by HPCA knockdown. Consistently, Elavl3 suppression phenocopied HPCA deficiency, resulting in impaired NMDA receptor activity and reduced neuronal differentiation. Furthermore, hippocampal HPCA knockdown in vivo led to alterations in locomotor activity, contextual memory, and affective behaviors. Taken together, these findings demonstrate that HPCA supports NMDA receptor function and neuronal development, in part through Elavl3-associated pathways, and highlight HPCA as an important regulator of hippocampal function. Full article

Marine lectins function as pattern recognition receptors in innate immunity through carbohydrate-binding mechanisms. However, mechanistic evidence detailing intracellular signaling cascades (e.g., MAPK/NF-κB/JAK-STAT activation linked to defined cytokine outputs) remains taxonomically uneven. Bivalve mollusks—particularly the Mytilectin family—represent the most extensively characterized group, whereas lectins from other marine phyla (echinoderms, cnidarians, fish, algae) have been studied primarily for structural and glycan-binding properties alongside phenotypic antimicrobial outcomes. Signaling-level resolution in native immune-cell contexts, while present in some cases, remains comparatively limited. This review synthesizes mechanistic insights dominated by bivalve-derived lectins, while integrating cross-taxa comparisons at evidence-supported levels. Specific bivalve lectins induce macrophage activation and pro-inflammatory cytokine production through reactive oxygen species-dependent activation of key signaling pathways including MAPK, NF-κB, and JAK-STAT cascades. These lectins exhibit context-dependent properties, promoting inflammatory responses in resting cells while inducing endotoxin tolerance in pre-activated macrophages through epigenetic reprogramming. Functional outcomes include broad-spectrum antiviral activity through viral envelope glycoprotein binding, anti-inflammatory effects in pain models, and cancer-associated immune responses through tumor glycan recognition and macrophage polarization. Critical gaps include uncharacterized effects on adaptive immunity, limited understanding of dendritic cell and natural killer cell interactions, and incomplete evaluation of cancer immunotherapy potential. Future research should prioritize mechanistic characterization of marine lectin-based immunotherapeutics. Full article

Background: Brucella outer membrane proteins (Omps) are an important part of its cell wall and major virulence-related factors. Omp16 and Omp19 proteins are the advantageous antigens of Brucella and have been widely used in research on vaccines against brucellosis. As an emerging vaccine, the mRNA vaccine has unique advantages in the fight against intracellular parasitic bacteria. Methods: In this study, mRNA encoding the omp16 and omp19 genes of Brucella. melitensis (B. melitensis) was synthesized using in vitro transcription. The target mRNA was transfected into HEK 293T cells to evaluate protein expression levels and assess its immunogenicity. Finally, bioinformatic approaches were employed to analyze potential antigenic epitopes. Results: In this study, the successfully constructed recombinant plasmids pIVTRup-omp16 and pIVTRup-omp19 were utilized to synthesize omp16-mRNA and omp19-mRNA, each approximately 600 nt in length. Western blot analysis detected the expression of proteins with molecular weights of 16 kDa and 19 kDa in HEK 293T cells at 24 h post-transfection with mRNA. Purified rOmp16 and rOmp19 had good immunogenicity, which could specifically bind to serum antibodies of brucellosis patients. rOmp16 had stronger immunogenicity than rOmp19. Epitope prediction showed that Omp16 contained seven epitopes and Omp19 contained six epitopes. In addition, Omp16 and Omp19 could form stable complexes with target receptors. Simulated immunization with Omp16 and Omp19 proteins significantly activated both CD4⁺ and CD8⁺ T cells. Conclusions: The immunogenic proteins were successfully expressed in cells based on the mRNA fragments synthesized from omp16 and omp19 genes of B. melitensis, which was a preliminary exploration for the preparation of B. melitensis mRNA vaccine. Full article

Diabetic kidney disease (DKD) is a major complication of diabetes mellitus that contributes substantially to chronic kidney failure and increased cardiovascular risk. Beyond progressive deterioration of renal function, DKD is associated with disturbances in endocrine and vascular regulation. Among these, alterations in vitamin D homeostasis and blood pressure (BP) control represent clinically relevant, yet incompletely integrated aspects of DKD pathophysiology. This narrative review synthesizes current evidence on the multidirectional relationships between DKD, vitamin D deficiency, and arterial hypertension (AH). Attention is given to renal mechanisms responsible for reduced vitamin D availability in DKD, including proteinuria-related loss of vitamin D-binding proteins, impaired proximal tubular reabsorption, decreased renal activation of vitamin D, and hormonal regulators such as fibroblast growth factor-23. It further discusses how insufficient vitamin D signaling may influence renal and vascular pathways involved in BP regulation. Mechanistic links between vitamin D deficiency and AH in DKD are discussed, with emphasis on maladaptive activation of the renin–angiotensin–aldosterone system (RAAS), persistent inflammation, oxidative stress, endothelial dysfunction, and insulin resistance. These interdependent processes promote both renal injury progression and sustained elevations in BP, forming a self-reinforcing pathogenic loop. Finally, available data on vitamin D-based therapeutic strategies in DKD are reviewed, including native vitamin D supplementation, active vitamin D metabolites, and vitamin D receptor agonists. Although experimental and observational studies suggest potential nephroprotective and vasculoprotective effects, evidence from randomized clinical trials remains heterogeneous. Further well-designed prospective studies are required to clarify the clinical utility of vitamin D interventions in patients with DKD and coexisting AH. Full article

Background. NOTCH receptors play a pivotal role in carcinogenesis. Upon ligand binding, a cascade of proteolytic cleavages mediated by ADAM proteases and the γ-secretase complex activates the receptor, ultimately releasing the NOTCH intracellular domain (NICD). NICD translocates to the nucleus, where it regulates gene expression. This review mainly aims to evaluate γ-secretase inhibitors (GSIs) as anticancer agents in preclinical and clinical settings, with a focus on their ability to block tumor progression, target cancer stem cells, and overcome resistance to standard therapies. Methods. A systematic search was conducted in the ISI Web of Science, PubMed, and Scopus databases, following PRISMA guidelines. The review included preclinical in vitro and in vivo studies, as well as clinical trials, investigating GSIs, either as monotherapy or in combination with other treatments, in TNBC, metastatic melanoma, PDAC, gastric cancer, and NSCLC. Exclusion criteria included duplicates, non-English articles, studies published before 2010, studies on non-cancer conditions, research unrelated to NOTCH signaling, and studies outside the selected cancer types. Overall, 69 articles were included and categorized into the five types of cancer analyzed (20 on NSCLC, 22 on TNBC, 11 on metastatic melanoma, 7 on GC, and 9 on PDAC). Of these, 60 studies corresponded to preclinical research in the types of cancer, and 9 studies corresponded to clinical trials in the types of cancer except for GC. Two independent authors screened and extracted relevant data, with disagreements resolved by the corresponding author. Findings were synthesized qualitatively across cancer types under study. Results. This review summarizes therapeutic advances involving GSIs in cancers driven by oncogenic NOTCH signaling, based on the 69 articles included. Preclinical studies show that GSIs synergize with chemotherapy and radiotherapy, particularly in NSCLC, melanoma, and TNBC, and block EMT, overcome therapeutic resistance, and improve prognosis. Commonly used GSIs include DAPT and RO4929097, which enhance the efficacy of agents, such as gemcitabine (PDAC), paclitaxel, osimertinib, erlotinib, and crizotinib (NSCLC), and 5-FU (gastric cancer, TNBC). Promising strategies include combining GSIs with SAHA, ATRA, CB-103, and other NOTCH signaling targeting molecules, either alone or with chemo- and radiotherapy. Clinical trials with GSIs, however, remain limited. RO4929097 is the most extensively tested GSI in clinical settings. PDAC trials combining GSIs with gemcitabine showed no benefit; melanoma trials yielded modest outcomes; and TNBC trials demonstrated partial responses to GSIs but overall low efficacy and significant adverse events. Discussion and Conclusions. Despite encouraging preclinical evidence, clinical trials with GSIs have underperformed, largely due to tumor heterogeneity, dosing limitations, and the non-selective nature of γ-secretase inhibition. Other NOTCH inhibitors, such as DLL4 antibodies, also resulted in partial responses and secondary effects. Future strategies should prioritize receptor-specific NOTCH inhibitors, patient stratification based on NOTCH pathway activation, and optimized combination regimens. Emerging approaches include integrating immunotherapy with advanced technologies such as CRISPR, CAR-T cells, and bispecific antibodies, as well as targeted delivery systems to enhance efficacy and reduce toxicity. Additional research directions include addressing the tumor microenvironment and EMT-driven resistance, elucidating the mechanisms of immune evasion, and inhibiting tumor angiogenesis. Finally, leveraging artificial intelligence and big-data-driven personalized medicine, including sex-specific considerations, will be essential for improving patient outcomes. Full article

Background: There is currently increasing interest in atypical opioid compounds capable of expanding their clinical applications beyond pain management, including the treatment of psychiatric disorders and substance abuse. In this context, the cyclotetrapeptide c[Trp-Phe-D-Pro-Phe] (CJ-15,208, 1) and its derivatives represent an unusual class of opioid peptides. This compound was found to be a mixed KOR/MOR antagonist in vitro, but it acted as an agonist in vivo. For its diverse analogues, it appeared that receptors’ affinity, selectivity, and agonist/antagonist activity greatly varied upon modifications to backbone geometry and the 3D display of pharmacophores. Methods: We utilized NMR, molecular dynamics, and molecular docking to analyze 3D structures and pharmacodynamic properties of selected representative cyclopeptide analogues of 1. Results: The simulations support that, despite its contradictory functional activity in vitro and in vivo, 1 can bind to the active conformation of receptors in an agonist-like fashion. In general, Trp appeared to be the fundamental pharmacophore in the ligand–receptor complexes. In particular, agonists showed a direct interaction between the indole ring and the carboxylate of the conserved Asp(3:32). Conclusions: These studies support a distinctive pharmacodynamic model for this class of compounds, potentially useful for the design of opioid compounds with novel binding/activity profiles and improved therapeutic effects. Full article

Complement and pathogenic antibodies act independently and together to mediate the pathology of many autoimmune diseases. To address these drivers of disease, we generated a monoclonal antibody (mAb), CSL305, that binds and inhibits both complement and the neonatal Fc (fragment crystallizable) receptor FcRn. The fragment antigen binding (Fab) portion of CSL305 was engineered to bind both human C2 (huC2) zymogen and the active fragment huC2b to inhibit the classical and lectin complement pathways in vitro, and C3b deposition on primary lung endothelial cells using a 3-dimensional microvascular model system. Engineering of a triple amino acid mutation (“YPY” motif) into the Fc region of CSL305 increased its affinity to FcRn at both acidic and neutral pH, allowing it to also act as a potent FcRn antagonist. Intracellular trafficking experiments demonstrated that CSL305, but not the wild-type (WT) mAb lacking the YPY motif, was able to block immunoglobulin G (IgG) recycling in vitro. The generation of a high resolution 2.6Å crystal structure of CSL305 Fab region bound to huC2b showed that the epitope lies directly over the huC2b catalytic triad, providing evidence of its complement mechanism of action as a neutralising mAb. Early pharmacokinetic (PK)/pharmacodynamic (PD) studies using CSL305 in cynomolgus monkeys demonstrated both complement inhibition and FcRn antagonism in vivo, with reductions in complement classical pathway activity and endogenous IgG observed following single intravenous (IV) administration. CSL305 thus represents a dual-functional mAb as a potential therapeutic candidate. Full article

The spherical pectin is an important bioactive component of chrysanthemum tea infusion, but its biological function, primary structure, and structure-activity relationship remain unclear. The present study evaluated the immunostimulatory activity of spherical pectin from Chrysanthemummorifolium Ramat. ‘Hangbaiju’ tea infusion in RAW264.7 cells and preliminarily investigated its structure-immunostimulatory activity relationship. The rhamnogalacturonan-I (RG-I) domain played a key role in the immunostimulatory activity of spherical pectin. Terminal and branched arabinose residues together accounted for 73.8% of the total arabinose residues in spherical pectin, indicating that the arabinan chains of spherical pectin were highly branched. The backbone of these arabinan chains consisted of →5)-α-Araf-(1→ repeats, and additional →5)-α-Araf-(1→ branches were linked to the backbone via α-1,3-glycosidic linkages. The spherical pectin rich in highly branched arabinan chains activated RAW264.7 cells via recognition by toll-like receptor 4 (TLR4). Molecular docking analysis revealed that →5)-α-Araf-(1→ branches in spherical pectin could bind to toll-like receptor 4/myeloid differentiation protein-2 (TLR4/MD-2) complexes and stabilize the dimer structure, which represents an important mechanism for its immunostimulatory activity. This study provides new insights into the structure-function relationship of spherical pectin. Full article

Background/Objectives: Thrombin, a serine protease central to coagulation and platelet activation, remains an important target for the development of safer and more effective antithrombotic agents. Naturally derived pentacyclic triterpenoids, such as betulinic acid and its acetylated derivatives, 3β-acetoxybetulinic acid, exhibit promising antiplatelet aggregation activity in validated in vitro and ex vivo assays; however, the molecular determinants underlying their direct thrombin inhibition remain unexplored. Results: Docking and MM/GBSA analyses revealed that Baa exhibits the strongest binding affinity (ΔG = −29.58 ± 2.97 kcal/mol), exceeding those of Ba (−20.94 ± 5.81 kcal/mol) and Asp (−18.87 ± 4.18 kcal/mol). Baa forms a highly persistent hydrogen bond with Trp96 (95.5% occupancy) and extensive hydrophobic contacts with Trp215, Leu99, Ile174, and Tyr60A residues defining thrombin’s aryl-binding pocket. MD trajectories demonstrated that Baa binding reduced solvent-accessible surface area (SASA) and residue fluctuations, indicating enhanced structural compaction and stability. In contrast, Ba exhibited weaker, transient hydrogen bonding, while Asp bound primarily near the catalytic triad. The triterpenes exhibit limited oral bioavailability, free PAINS alerts, favourable permeability and metabolic stability. Conclusions: Acetylation at C-3 (acetoxy substitution) substantially enhances thrombin binding via cooperative hydrogen bonding and van der Waals stabilisation, explaining the superior experimental inhibitory potency of Baa. These findings provide a mechanistic framework for structure-guided optimisation of triterpenoid-based thrombin inhibitors and support their further experimental development. Methods: In this study, molecular docking, molecular dynamics (MD) simulations (400 ns), and MM/GBSA free energy analyses were employed to elucidate the binding mechanisms of 3β-acetoxybetulinic acid (Baa), betulinic acid (Ba), and aspirin (Asp) within the thrombin receptor active site. The simulations were explicitly grounded in previously reported chromogenic antithrombin assays and platelet aggregation studies and were designed to mechanistically rationalise the experimentally observed inhibitory potency. Full article

The SARS-CoV-2 Omicron variant and its descendants accumulated unprecedented numbers of spike substitutions yet remained transmissible, implying compensatory mechanisms that preserve entry while eroding humoral immunity. We analyzed 32 variants for sequence-level mutation, physicochemical profiling, and epitope disruption; 25 had growth-advantage estimates, and 18 underwent molecular dynamics/MM-PBSA simulations. We applied a systems-virology framework to the SARS-CoV-2 receptor-binding domain (RBD), integrating immunodominance-weighted epitope conservation (567 B-cell and 97 T-cell epitopes) across variants (Wuhan-Hu-1 to KP.3) with molecular dynamics, molecular mechanics Poisson–Boltzmann surface area (MM-PBSA) binding energetics, and deep mutational scanning (DMS) benchmarking. B-cell epitope conservation declined from a median of 72.7% in pre-Omicron variants to 28.8% in BA.1 and 10.6% in KP.3, and was strongly inversely associated with a breakthrough-infection proxy (Spearman ρ = −0.8246, p < 0.001), whereas RBD T-cell epitopes remained comparatively conserved (91.5% to 87.2%). Despite the loss of the ancestral K417–ACE2 D30 salt bridge, Omicron reconfigured the interface via alternative electrostatic contacts (Q493R–E35 and Q498R–D38), producing compensatory interactions captured by MM-PBSA, but with only modest agreement with DMS affinity changes (r = 0.682, p = 0.007), consistent with enthalpy–entropy compensation. Finally, mutation tolerance shifted toward stronger epistatic buffering in Omicron (two-fold higher epistasis than pre-Omicron; p = 0.0093), enabling extensive antigenic change without structural collapse. Together, these results support a multi-objective evolutionary strategy—epitope erosion, interface rewiring, and epistatic compensation—that can be operationalized to prioritize emerging lineages for surveillance and to inform vaccine designs that emphasize conserved T-cell targets. Full article

Halogens, particularly fluorine, chlorine, and bromine, play a pivotal role in modern drug discovery and development. Their incorporation into drug molecules significantly influences physicochemical properties, including lipophilicity, metabolic stability, and target binding affinity. Fluorine, the most commonly used halogen, enhances bioavailability and receptor interactions, as seen in several blockbuster drugs. Chlorine and bromine contribute to hydrophobic interactions and modulate pharmacokinetics, while iodine is less frequently utilized due to its larger atomic size and reactivity. The strategic placement of halogens in drug scaffolds has led to the success of numerous FDA-approved pharmaceuticals across therapeutic areas, including oncology, infectious diseases, and central nervous system disorders. This review explores the structure–activity relationships (SAR) of halogen-containing drugs, highlighting recent approvals (2025), their synthesis (with yields, when available), therapeutic use, and, when experimentally available, the interaction with their biological target macromolecules. 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