Search Results (171)

Hydrogel scaffolds have emerged as instructive microenvironments for craniofacial tissue regeneration, moving beyond passive cell carriers toward platforms that regulate cell fate, vascularization, immune remodeling, and tissue-specific architecture. This review synthesizes hydrogel-associated strategies across dental pulp, periodontal ligament, gingival, bone marrow, jawbone, endothelial, oral mucosal, induced pluripotent stem cell (iPSC), extracellular vesicle (EV), exosome, secretome, and acellular systems. The evidence indicates that craniofacial hydrogel performance is governed by reciprocal interactions among biological source, scaffold composition, matrix mechanics, spatial architecture, mineral or ionic signaling, growth factor delivery, vesicle-mediated communication, and inflammatory niche modulation. Mineralized and ion-releasing hydrogels most consistently supported osteogenesis and bone repair, whereas extracellular matrix (ECM)-mimetic, peptide, collagen, fibrin, gelatin methacryloyl (GelMA), alginate, hyaluronic acid (HA), and chitosan-based systems enabled pulp–dentin, periodontal, peri-implant, oral mucosal, and soft-tissue reconstruction. Responsive, antimicrobial, antioxidant, conductive, and immunomodulatory hydrogels further expanded the field by targeting diseased microenvironments rather than regeneration alone. Despite strong preclinical evidence, translation remains limited by heterogeneity in scaffold formulations, biological sources, analytical endpoints, defect models, and long-term functional validation. Future progress will require standardized characterization, tissue-specific design criteria, clinically relevant large-animal models, scalable cell-free technologies, and integrated assessment of regeneration, immunity, vascularization, innervation, mechanics, and safety. Full article

Cationic antimicrobial peptides (AMPs) that can target multidrug-resistant pathogenic bacteria via multiple mechanisms are considered promising alternatives to antibiotics. Small (~9 kDa) highly acidic acyl carrier proteins (ACPs), which are a well-known cofactor protein in bacterial fatty acid synthesis (FAS), are a potential intracellular target for AMPs. A previous study has demonstrated that the human AMP LL-37 can bind to ACP and thereby affect FAS and the bacterial membrane integrity. In this work, we have investigated the interactions of different classes of AMPs and antibiofilm peptides (ABPs) with the ACPs of two pathogens. We first studied the folding characteristics of the two ACPs and found that Pseudomonas aeruginosa ACP (PaACP) is fully folded at neutral pH in the absence of divalent cations. On the other hand, the homologous Francisella novicida ACP (FnACP) is unfolded at low ionic strength, but it adopts a fully folded conformation after the addition of divalent cations such as Ca²⁺ or Mg²⁺. These distinct characteristics were shown to be related to a unique His residue that is involved in a stabilizing cation–π interaction. Subsequent biophysical SPR and NMR interaction studies reveal that cationic AMPs and ABPs such as LL-37, melittin, tritrpticin, indolicidin, puroindoline A, lactoferricin B and IDR-1018, but not F5W-magainin 2, can bind to both apo- and holo-ACPs. Binding of Arg-rich peptides is preferred over their Lys-rich analogs. Interestingly, all the peptides bind to holo-ACP with higher affinity than to apo-ACP, which lacks the functionally important phosphopantothenate group. NMR peak intensity perturbation data reveal that helix II of ACP, which is known to be directly involved in complex formation with bacterial FAS enzymes, acts as a common and main recognition site for the peptides. We propose that binding of AMPs and ABPs to this region of bacterial ACPs can directly block fatty acid synthesis and interfere in other ACP-dependent biosynthetic and regulatory events, which in turn could contribute to killing the bacteria and could also intervene in biofilm formation. Full article

Protein turnover and extracellular proteolysis continuously generate diverse peptide fragments within biological systems, yet the metabolic and pharmacological implications of these peptides remain incompletely understood. Among these transporters, members of the solute carrier family 15 (SLC15), including peptide transporter 1 (PEPT1/SLC15A1) and peptide transporter 2 (PEPT2/SLC15A2), mediate the proton-coupled uptake of dipeptides, tripeptides, and structurally related compounds across cellular membranes. While these transporters have been extensively studied in the context of intestinal peptide absorption and drug delivery, their potential roles in cancer biology remain incompletely understood. Tumor microenvironments are characterized by extensive proteolysis and dynamic metabolic remodeling, processes that can generate diverse peptide fragments derived from extracellular matrix proteins and intracellular protein turnover. These peptides may accumulate locally and potentially serve as substrates for cellular peptide transport systems. Once internalized through peptide transporters, dipeptides are typically hydrolyzed into free amino acids that can support biosynthetic pathways, energy metabolism, and cellular growth. In addition to their potential metabolic roles, certain endogenous dipeptides have also been reported to influence cellular signaling pathways and redox homeostasis. The broad substrate specificity of peptide transporters has also attracted significant interest in pharmacology because numerous clinically used drugs exploit these transport systems for efficient cellular uptake. This property raises the possibility that peptide transporters may be utilized for transporter-mediated drug delivery strategies, including the development of peptide-modified prodrugs or dipeptide–drug conjugates. In this review, we summarize the molecular characteristics and physiological functions of dipeptide transport systems with a particular focus on the SLC15 transporter family. We then discuss emerging evidence linking peptide transporters to tumor metabolism and the tumor microenvironment. Finally, we highlight current progress and future perspectives in exploiting peptide transport systems for transporter-mediated drug delivery and therapeutic targeting in cancer. Full article

Diabetic kidney disease (DKD) is a leading cause of end-stage renal disease. The Shen-Kang Recipe (SKR) is a traditional Chinese medicine formula used clinically to slow DKD progression, but its bioactive constituents and molecular targets remain unclear. Solute carrier family 15 member 2 (SLC15A2/PEPT2), a high-affinity peptide transporter expressed in renal proximal tubules, has been implicated in kidney pathophysiology, yet its potential role in mediating the therapeutic effects of the SKR has not been explored. Here, we evaluated the effects of the SKR in db/db mice and found that SKR treatment significantly improved renal function, attenuated glomerulosclerosis, and reduced interstitial collagen deposition. Wide-target metabolomics and quantitative proteomics revealed that the SKR broadly reversed DKD-associated metabolic and proteomic disturbances, particularly in pathways related to energy and amino acid metabolism. Proteomic analysis identified SLC15A2 as a key proximal tubule protein downregulated in DKD and selectively restored by the SKR. UPLC-Q-TOF/MS-based serum pharmacochemistry and network pharmacology highlighted quercetin as a principal bioactive component of the SKR. Molecular docking, molecular dynamics simulations, and surface plasmon resonance (SPR) confirmed direct, high-affinity binding between quercetin and SLC15A2 (KD = 7.5 µM). In TGF-β1-stimulated HK-2 cells, quercetin suppressed epithelial-mesenchymal transition (EMT), as evidenced by restored E-cadherin and reduced N-cadherin, vimentin, and α-SMA expression; this effect was abrogated by siRNA-mediated SLC15A2 knockdown, demonstrating the functional necessity of this axis. Collectively, these findings identify a quercetin-SLC15A2 axis through which the SKR inhibits EMT and alleviates renal fibrosis in DKD, providing a mechanistic basis for its clinical application and nominating SLC15A2 as a potential therapeutic target. Full article

In this study, hydrolyzed whey was obtained using pancreatin as the proteolytic enzyme, and its antihypertensive activity was evaluated. The hydrolysis was carried out for 7 h, and the resulting products were analyzed for antihypertensive in vitro activity by inhibiting angiotensin-converting enzyme (ACE). The hydrolysate demonstrated a 42 ± 3.38% ACE inhibition after 7 h of hydrolysis, indicating the effective release of bioactive peptides. Electrophoresis analysis revealed peptides with molecular weights below 6.5 kDa, consistent with known antihypertensive peptides. The hydrolysate was then incorporated as a functional ingredient into a dairy beverage. However, the beverage’s ACE-inhibitory activity was lower, reaching only 11.88 ± 0.26% inhibition. However, the dairy beverage retained low-molecular-weight peptides. Despite the lower antihypertensive activity in the final product, the results highlight the potential of hydrolyzed whey as a functional ingredient for developing functional dairy beverages. For that reason, the research aimed to evaluate the potential of a dairy beverage prepared with whey hydrolyzed by pancreatin as a carrier of antihypertensive peptides. Full article

Copper and zinc nanoparticles have been suggested as potent anticancer agents, particularly against osteosarcoma, a highly aggressive bone cancer with limited treatment options. In order to avoid systemic toxicity, biomolecular carriers able to chelate metal ions and deliver them in a targeted manner to the vicinity of cancer cells need to be developed. Herein, we have used a histidine-containing, cyclic dipeptide as a carrier able to chelate stabilized copper and zinc nanoparticles. The cyclic peptide cyclo-(histidine-phenylalanine) (cHF) self-assembled into amyloid-type fibrils; morphological and structural characterization following metal addition confirmed the formation of cHF−CuNPs and cHF–ZnNPs. These composite nanoparticles demonstrated bacteriostatic activity against Escherichia coli and Staphylococcus aureus at the in vitro level. We evaluated the optimal concentration of cHF–metalNP complexes with limited cytotoxicity to L929 fibroblasts and high cytotoxic effects against MG-63 osteosarcoma cells. Their cytotoxicity was particularly pronounced at pH 6.4, which emulates the tumor microenvironment. The cHF peptide alone did not demonstrate significant antimicrobial or cytotoxic effects to both cell types, suggesting that it can act as a cytocompatible, pH-responsive carrier of metal ions with targeted dual functionality against both microbial infections and osteosarcoma cancer cells. Full article

Host defense peptides (HDPs), ancestral effectors of innate immunity, have emerged as pleiotropic regulators transcending their antimicrobial origins. This review critically examines the complex interplay among HDPs, hemostasis, and tissue repair. We analyze molecular mechanisms governing interactions with platelets and endothelial cells, highlighting a fundamental paradigm shift: platelets and megakaryocytes are active synthesizers of a specific peptide repertoire rather than passive carriers. Functional dualities are elucidated, contrasting LL-37-driven platelet agonism via glycoprotein VI (GPVI) against the amyloid-like stabilization of fibrin by defensins. Based on these mechanisms, we propose a framework wherein HDPs function as concentration-dependent molecular switches between physiological repair and pathological thromboinflammation. Furthermore, the review addresses the hypothesis of “adaptive thrombopoiesis,” where systemic peptide surges act as danger signals to reprogram the function of newly formed platelets. Finally, therapeutic implications are evaluated, emphasizing the design of protease-resistant peptidomimetics to harness protective effects while mitigating vascular toxicity. Full article

Epigenetics involves heritable changes in gene expression—such as DNA methylation (5-methylcytosine; 5mC), histone modifications, and regulation by non-coding RNAs at the mRNA translation level—without altering the underlying DNA sequence. As targeting these mechanisms enables intervention at the root cause of disease rather than the symptoms alone, epigenetics has become a rapidly advancing field in pharmaceutical sciences. Various epigenetic modulators, including histone deacetylase (HDAC) inhibitors, histone acetyltransferase (HAT) inhibitors, DNA methyltransferase (DNMT) inhibitors, and microRNAs (miRNAs), have been developed, and some have already been approved for cancer therapy. However, these agents often face significant challenges such as poor membrane permeability, enzymatic instability, and suboptimal biodistribution. Incorporating functionalized accessory units—serving as vectors (e.g., transporter recognition units, cell-penetrating peptides, tumor-homing peptides, monoclonal antibodies) or as carriers (e.g., monoclonal antibodies, nanoparticles)—into epigenetic modulators may help overcome these delivery barriers. In this narrative review, I discuss the potential and advantages of effective non-invasive delivery of epigenetic drugs using such functionalized accessory unit conjugates. Full article

Signaling mediated by CLAVATA3/EMBRYO SURROUNDING REGION-RELATED (CLE) peptides and their receptors is essential for plants to adapt to abiotic stress. To address the global issue of drought-induced growth inhibition and mortality in poplar (Populus spp.), this study investigated the function of the PtrCLE1A gene from Populus trichocarpa Torr. et Gray in drought tolerance regulation. We employed gene cloning, expression vector construction, and genetic transformation of poplar, combined with bioinformatics analysis, subcellular localization, phenotypic observation, physiological index measurement, and gene expression analysis. The results demonstrated that both PtrCLE1A and PtrCLE1B encode pre-propeptides containing a signal peptide, with an identical mature peptide sequence (RLSPGGPDPRHH), and their putative receptors are PtrCLV1/2. Furthermore, the PtrCLE1A pre-propeptide was localized around the plasma membrane in tobacco (Nicotiana benthamiana Domin) mesophyll cells, consistent with its predicted function. PtrCLE1A and PtrCLE1B are primarily expressed in the roots and xylem of P. trichocarpa. Additionally, only the PtrCLE1A promoter contained drought-responsive cis-elements, and its expression was induced by drought stress in root, xylem, and leaf tissues of P. trichocarpa. Overexpression of the PtrCLE1A gene in Populus tomentosa Carrière (triploid) significantly increased adventitious root length under osmotic stress. Overexpression lines exhibited 22.00% to 22.92% longer adventitious roots than EV lines at 50/100 mM mannitol, and 65.12% to 73.17% longer at 150 mM mannitol. The OE lines also exhibited higher photosynthetic capacity and instantaneous water use efficiency (iWUE), along with reduced membrane damage under drought conditions, indicating enhanced drought resistance. This study provides new genetic resources and a theoretical foundation for molecular breeding of drought-tolerant poplar. Full article

Therapeutic peptides have emerged as promising tools in oncology due to their high specificity, favorable safety profile, and capacity to target molecular hallmarks of cancer. Their clinical translation, however, remains limited by poor stability, rapid proteolytic degradation, and inefficient biodistribution. Iron oxide nanoparticles (IONPs) offer a compelling solution to these challenges. Owing to their biocompatibility, magnetic properties, and ability to serve as both drug carriers and imaging agents, IONPs have become a versatile platform for precision nanomedicine. The integration of peptides with IONPs has generated a new class of hybrid systems that combine the biological accuracy of peptide ligands with the multifunctionality of magnetic nanomaterials. Peptide functionalization enables selective tumor targeting and deeper tissue penetration, while the IONP core supports controlled delivery, MRI-based tracking, and activation of therapeutic mechanisms such as magnetic hyperthermia. These hybrids also influence the tumor microenvironment (TME), facilitating stromal remodeling and improved drug accessibility. Importantly, the iron-driven redox chemistry inherent to IONPs can trigger regulated cell death pathways, including ferroptosis and autophagy, inhibiting opportunities to overcome resistance in aggressive or refractory tumors. As advances in peptide engineering, nanotechnology, and artificial intelligence accelerate design and optimization, peptide–IONP conjugates are poised for translational progress. Their combined targeting precision, imaging capability, and therapeutic versatility position them as promising candidates for next-generation cancer theranostics. Full article

Background: Atrial dilated cardiomyopathy (ADCM) related to homozygous Natriuretic Peptide Precursor A (NPPA) pathogenic variants is an exceptionally rare inherited atrial cardiomyopathy characterized by progressive atrial enlargement, supraventricular arrhythmias, and eventual atrial standstill. Case summary: We report the case of a 9-year-old girl identified through population genetic screening as a homozygous carrier of the NPPA c.449G>A (p.Arg150Gln) variant who subsequently developed symptomatic paroxysmal atrial fibrillation (AF) at the age of 18. Although baseline cardiac investigations were normal, her current evaluation shows biatrial enlargement with preserved ventricular function. She underwent radiofrequency pulmonary vein isolation; however, recurrent symptomatic AF persists, requiring ongoing antiarrhythmic therapy and long-term oral anticoagulation (CHA₂DS₂-VA: 0; HAS-BLED: 0). Notably, patients with NPPA-related ADCM have a markedly increased thromboembolic risk due to progressive atrial mechanical failure, and anticoagulation should therefore be considered irrespective of conventional clinical risk scores. Discussion and conclusions: This case highlights the importance of genetic testing in young patients with atrial fibrillation and no underlying structural heart disease. The early identification of NPPA-related atrial dilated cardiomyopathy may aid in risk stratification and guide rhythm and anticoagulation management. Expanding genetic screening in select individuals with isolated atrial fibrillation may facilitate earlier diagnosis in this exceptionally rare condition. Full article

Reusable enzyme carriers are valuable for proteomic workflows, yet many supports are expensive or lack robustness. This study describes the covalent immobilization of recombinant trypsin on micrometer-sized corundum particles and assesses their performance in protein digestion and antibody analysis. The corundum surface was cleaned with potassium hydroxide, silanized with 3-aminopropyltriethoxysilane and activated with glutaraldehyde. Recombinant trypsin was then attached, and the resulting imines were reduced with sodium cyanoborohydride. Aromatic amino acid analysis (AAAA) estimated an enzyme loading of approximately 1 µg/mg. Non-specific adsorption of human plasma proteins was suppressed by blocking residual aldehydes with a Tris-glycine-lysine buffer. Compared with free trypsin, immobilization shifted the temperature optimum from 50 to 60 °C and greatly improved stability in 1 M guanidinium hydrochloride. Activity remained above 80% across several reuse cycles, and storage at 4 °C preserved functionality for weeks. When applied to digesting the NISTmAb, immobilized trypsin provided peptide yields and sequence coverage comparable to soluble enzyme and outperformed it at elevated temperatures. MALDI-TOF MS analysis of Herceptin digests yielded fingerprint spectra that correctly identified the antibody and achieved >60% sequence coverage. The combination of low cost, robustness and analytical performance makes corundum-immobilized trypsin an attractive option for research and routine proteomic workflows. Full article

Atrial dilated cardiomyopathy with progression to atrial standstill is an ultrarare arrhythmogenic disorder characterized by complete loss of atrial electrical and mechanical activity. This condition, which may occur sporadically or in familial clusters, is associated with a markedly increased thromboembolic risk. The electrocardiographic hallmark is the absence of P waves combined with a bradycardic junctional escape rhythm. Biatrial enlargement gradually evolves into giant atria with preserved biventricular systolic function, while supraventricular arrhythmias and progressive atrial inexcitability dominate the clinical course. Valvular regurgitation frequently worsens in parallel with atrial remodelling, and patients often require permanent pacemaker implantation as well as lifelong anticoagulation. Among the few genetic determinants identified, the homozygous c.449G>A (p.Arg150Gln) mutation in the Natriuretic Peptide A gene represents one of the best characterized mechanisms. Disertori et al. first reported this pathogenic variant in 13 affected individuals from Italian families, establishing a recessive inheritance pattern. More recently, Silva et al. and Forleo et al. described additional cases, expanding the phenotypic spectrum of NPPA-related atrial cardiomyopathy. These findings confirm that homozygous carriers develop a severe atrial phenotype, whereas heterozygous relatives typically remain asymptomatic, underlining the importance of genetic testing in young patients with unexplained atrial fibrillation or standstill. Recognition of atrial cardiomyopathy as a distinct clinical entity is crucial, since early diagnosis may guide timely anticoagulation, arrhythmia management, and tailored follow-up. Broader adoption of genetic screening in patients with isolated atrial dysfunction could support precision medicine approaches, improve risk stratification, and ultimately prevent adverse outcomes in this ultrarare but highly morbid condition. Full article

Background/Objectives: Cell-mediated and peptide-assisted delivery systems have emerged as powerful platforms at the intersection of chemistry, nanotechnology, and molecular medicine. By leveraging the intrinsic targeting, transport, and signaling capacities of living cells and bioinspired peptides, these systems facilitate the delivery of therapeutic agents across otherwise restrictive biological barriers such as the blood–brain barrier (BBB) and the tumor microenvironment. This review aims to summarize recent advances in engineered cell carriers, peptide vectors, and hybrid nanostructures designed for enhanced intracellular and tissue-specific delivery. Methods: We surveyed recent literature covering molecular design principles, mechanistic studies, and in vitro/in vivo evaluations of cell-mediated and peptide-enabled delivery platforms. Emphasis was placed on neuro-oncology, immunotherapy, and regenerative medicine, with particular focus on uptake pathways, endosomal escape mechanisms, and structure–function relationships. Results: Analysis of current strategies reveals significant progress in optimizing cell-based transport systems, peptide conjugates, and multifunctional nanostructures for the targeted delivery of drugs, nucleic acids, and immunomodulatory agents. Key innovations include improved BBB penetration, enhanced tumor homing, and more efficient cytosolic delivery enabled by advanced peptide designs and engineered cellular carriers. Several platforms have progressed toward clinical translation, underscoring their therapeutic potential. Conclusions: Cell-mediated and peptide-assisted delivery technologies represent a rapidly evolving frontier with broad relevance to next-generation therapeutics. Despite notable advances, challenges remain in scalability, manufacturing, safety, and regulatory approval. Continued integration of chemical design, molecular engineering, and translational research will be essential to fully realize the clinical impact of these delivery systems. Full article

Backgroud/Objectives: Canine Visceral Leishmaniasis (CVL), caused by Leishmania infantum, is a significant public health concern due to dogs serving as reservoirs for human infection. An accurate and rapid diagnostic method to distinguish symptomatic and asymptomatic CVL from healthy and vaccinated animals is essential for controlling canine and human disease. Developing innovative antibody detection techniques and exploring new antigens are essential for enhancing CVL testing efficiency. Our study focuses on a multiplex flow cytometry technique to detect Leishmania-specific antibodies in canine serum. This involved conjugating small peptides with carrier proteins or peptide tags, sequences designed to facilitate bead coupling. Methods: A peptide from the L. infantum A2 protein was coupled to beads in three forms: unconjugated, conjugated with BSA, and conjugated with a C-terminal β-alanine–lysine (x4)–cysteine TAG. This TAG was previously designed to enhance peptide solubility, improve binding efficiency, and provide functional groups for covalent attachment to the beads, ensuring stable immobilization in the multiplex assay. Results: Our results suggest that the multiplex approach shows promise as a rapid serological test for CVL, particularly with TAG-conjugated peptides, which optimize bead coupling. However, peptide/BSA conjugation revealed anti-BSA antibodies in samples from healthy and CVL dogs. Conclusions: In conclusion, our findings highlight the potential of multiplex methodologies to enhance CVL diagnostics and caution against using BSA as a bead coupling agent in serological tests for canine samples due to its impact on test specificity and sensitivity. Full article