Search Results (1,399)

The physiological relevance of in vitro models is limited because conventional two-dimensional cell culture systems are unable to replicate the structural and functional complexity of native tissues. Extracellular matrix (ECM)-mimetic hydrogels have become important platforms for tissue engineering applications. This work developed hybrid hydrogels that mimic important biochemical and mechanical characteristics of cardiac tissue by combining decellularized bovine pericardium-derived (dBP) ECM, gellan gum (GG), and spermine (SPM). Although dBP offers tissue-specific biological cues, processing compromises its mechanical integrity. This limitation was overcome by adding GG, whose ionic gelation properties were optimized using DMEM and SPM. The hydrogels’ mechanical, biological, physicochemical, and structural characteristics were all evaluated. Under physiologically simulated conditions, the formulations showed quick gelation and long-term stability; scanning electron microscopy revealed an interconnected, ECM-like porous microarchitecture. While uniaxial compression testing provided Young’s modulus values comparable to native myocardium, rheological analysis revealed a concentration-dependent increase in storage modulus with increasing SPM content. H9C2 cardiomyoblasts were used in cytocompatibility studies to confirm that cell viability, morphology, and cytoskeletal organization were all preserved. All of these findings support the potential application of dBP−GG−SPM hydrogels in advanced in vitro cardiac models by showing that they successfully replicate important characteristics of cardiac ECM. Full article

Ex vivo functional testing for multiple myeloma is rapidly evolving, yet no single assay has reached the level of reliability and clinical utility needed for routine decision-making. Existing approaches generally fall into three categories: 2D cultures, 3D models, and dynamic systems. Each contributes valuable but incomplete insight into therapeutic response. Among these, 2D assays remain the most mature, with the most extensive clinical correlations to date, though their simplified architecture limits their ability to reflect the full complexity of the bone marrow microenvironment. However, 3D systems, including spheroids and matrix-based organoids, offer improved preservation of tumor heterogeneity and microenvironmental cues. These platforms show emerging clinical relevance and may hold advantages over traditional 2D formats, and validation efforts are developing. Dynamic systems, including microfluidic models and perfused bone-marrow mimetics, represent the most physiologically ambitious category, yet their technical intricacy and early stage of development have so far limited broad clinical correlation. Altogether, the current landscape highlights substantial progress but lacks an optimal assay. In this review, we take the unique approach of examining published ex vivo tests that have demonstrated a level of clinical correlation. We evaluate their respective formats, strengths and limitations, and discuss considerations for what an ideal future assay may encompass. Full article

Background: Human Immunodeficiency Virus type 1 (HIV-1) remains a major global health challenge. Despite advances in antiretroviral therapy, new prevention strategies are needed, particularly topical microbicides capable of blocking the earliest steps of viral entry. HIV-1 attachment relies on interactions with heparan sulfate proteoglycans on host cell surfaces; therefore, sulfated heparan-mimetic polymers have been explored as antiviral agents. In this context, sulfated chitosan microparticles are designed to mimic natural glycosaminoglycan receptors, acting as biomimetic decoys that prevent viral attachment and entry. Methods: Low-molecular-weight sulfated chitosan (LMW Chi-S) microparticles were synthesized and characterized (SEM, EDS, DLS, FTIR) following US Patent No. 11,246,839 B2. Their antiviral activity was evaluated by incubating the microparticles with high-viral-load HIV-1-positive plasma (~3.5 × 10⁶ copies/mL) to enable viral binding and removal by pull-down. The performance of the synthesized Chi-S microparticles was compared with established heparinoid controls, including soluble heparin and heparin microparticles. Results: Chi-S microparticles exhibited stronger virus-binding and neutralizing capacity than all heparinoid comparators, achieving up to 70% reduction in viral load relative to untreated HIV-1 plasma. In comparison, soluble heparin and heparin microparticles reduced viral load by approximately 53% and 60%, respectively. Subsequent evaluation across multiple tested concentrations confirmed a consistent antiviral effect, indicating that the synthesized Chi-S microparticles maintain robust virus–particle interactions throughout the concentration range examined. Conclusions: These findings demonstrate that LMW Chi-S microparticles possess potent antiviral properties and outperform classical heparinoid materials, supporting their potential application as topical microbicides targeting early HIV-1 entry mechanisms. Full article

The BCL-2 family of proteins plays a central role in the regulation of apoptosis, with BCL-2 and BCL-xL representing two of its most prominent antiapoptotic members. This review explores the molecular regulation of BCL-2 and BCL-xL genes, emphasizing the structural domains that define the functions of the broader BCL-2 family. Beyond their canonical roles in preventing mitochondrial outer membrane permeabilization, both proteins contribute significantly to cancer development. Their overexpression enhances invasiveness and tumor progression, supports angiogenesis, and critically modulates cellular responses to chemotherapy, often conferring drug resistance. Additional non-apoptotic functions, including roles in metabolism, mitochondrial dynamics, and cellular homeostasis, further expand their biological relevance. Clinical trials exploring strategies to inhibit BCL-2 and BCL-xL, including selective BH3 mimetics and combination regimens, are discussed with emphasis on their potential and limitations in oncology. Overall, this review highlights the multifaceted contributions of BCL-2 and BCL-xL to cancer biology and underscores the importance of continued efforts to refine targeted therapeutic approaches. Full article

Caffeoyl hexapeptide-9 (CH-9) is a novel cosmetic peptide designed by conjugating hexapeptide-9 (H-9), a known collagen-mimetic peptide with established skin anti-aging activity, with caffeic acid (CA) via an amide bond, leveraging peptide-drug conjugate (PDC) design principles. In ultraviolet (UV)-irradiated cellular and skin models, CH-9 outperformed H-9 in preserving cell viability, restoring collagen types I, III, and IV, and suppressing interleukin-6 and -8 secretion. Additionally, its direct antioxidant activity, absent in H-9, was demonstrated in vitro by scavenging of hydroxyl and peroxyl radicals. Molecular docking indicated CH-9 interacted with the catalytic domain of matrix metalloproteinase 2 (MMP2), a key enzyme in collagen degradation during photoaging, suggesting a potential inhibition of its activity. Molecular dynamics (MD) simulations revealed an improved insertion of CH-9 into a stratum corneum (SC) lipid bilayer compared to H-9, consistent with enhanced skin permeation in vivo. Moreover, CH-9 exhibited improved aqueous and cosmetic serum stability over CA. In a 28-day clinical study, topical application of CH-9 significantly improved skin elasticity and firmness compared to H-9. This work demonstrates that the PDC-based conjugate CH-9 combines enhanced anti-photoaging efficacy with improved transdermal permeation and stability, highlighting a promising strategy for the development of advanced cosmetic ingredients. Full article

4-hydroxy-TEMPO is a water-soluble nitroxide radical with potent antioxidant and redox-modulating properties. Its small molecular weight and membrane permeability enable it to act as a superoxide dismutase mimetic, efficiently scavenging reactive oxygen species and mitigating oxidative damage. In this study, we investigated the physiological and transcriptomic effects of 4-hydroxy-TEMPO in Saccharomyces cerevisiae, using wild-type and mutant strains deficient in key redox and DNA repair pathways (sod1Δ, sod2Δ, yap1Δ, rad52Δ). RNA-Seq analysis revealed widespread transcriptional reprogramming. Treatment with 4-hydroxy-TEMPO impaired cell growth, induced accumulation of cells with 1C (G1 phase) DNA content, and modulated chronological aging in a strain-dependent manner. Notably, low concentrations delayed aging in wild-type, yap1Δ, and rad52Δ strains, while accelerating it in sod1Δ mutants, consistent with a hormetic response. Unlike TEMPO, 4-hydroxy-TEMPO exhibited markedly reduced translational toxicity, preserved polysome structure at high doses, and triggered a non-canonical, redox-dependent transcriptional program characterized by induction of stress-response genes together with unexpected up-regulation of multiple ribosomal protein genes. This was accompanied by a biphasic, genotype-specific hormetic response and a measurable genoprotective effect. RT-qPCR confirmed key transcriptional changes, linking transcriptome remodeling to functional outcomes. Full article

The combination of gold nanoparticles (AuNPs) with hydrogels has drawn significant interest in the design of smart materials as advanced platforms for biomedical applications. These systems endow light-responsiveness enabled by the AuNPs localized surface plasmon resonance (LSPR) phenomenon. In this study, we propose a nanocomposite hydrogel in which gold nanorods (AuNRs) are included in an agarose–carbomer–hyaluronic acid (AC-HA)-based hydrogel matrix to study the correlation between light irradiation, local temperature increase, and drug release for potential light-assisted drug delivery applications. The gel is obtained through a facile microwave-assisted polycondensation reaction, and its properties are investigated as a function of both the hyaluronic acid molecular weight and ratio. Afterwards, AuNRs are incorporated in the AC-HA formulation, before the sol–gel transition, to impart light-responsiveness and optical properties to the otherwise inert polymeric matrix. Particular attention is given to the evaluation of AuNRs/AC-HA light-induced heat generation and drug delivery performances under near-infrared (NIR) laser irradiation in vitro. Spatiotemporal thermal profiles and high-resolution thermal maps are registered using fiber Bragg grating (FBG) sensor arrays, enabling accurate probing of maximum internal temperature variations within the composite matrix. Lastly, using a high-steric-hindrance protein (BSA) as a drug mimetic, we demonstrate that moderate localized heating under short-time repeated NIR exposure enhances the release from the nanocomposite hydrogel. Full article

Autologous fat grafting is the main surgical technique for soft tissue reconstruction. However, its clinical use with more extended volumes is limited by repeated procedures due to the little possibility of banking tissue, donor-site morbidity and unpredictable graft resorption rates. To overcome these problems, adipose tissue engineering has focused on developing injectable scaffolds. Most of them are hydrogels that closely mimic the biological, structural and mechanical characteristics of native adipose tissue. This review provides an overview of current injectable scaffolds designed to restore soft tissue volume defects, emphasizing their translational potential and future directions. Natural injectable scaffolds exhibit excellent biocompatibility but degrade rapidly and lack mechanical strength. Synthetic injectable scaffolds provide tunable elasticity and degradation rates but require biofunctionalization to support cell adhesion and tissue integration. Adipose extracellular matrix-derived injectable scaffolds are fabricated by decellularization of adipose tissue. Accordingly, they combine bio-mimetic structure with intrinsic biological cues that stimulate host-driven adipogenesis and angiogenesis, thus representing a translatable “off-the-shelf” alternative to autologous fat grafting. However, despite this broad spectrum of available injectable scaffolds, the establishment of clinically reliable soft tissue substitutes capable of supporting large-volume and long-lasting soft tissue reconstruction still remains an open challenge. Full article

While drug-eluting cardiovascular devices, including drug-eluting stents and drug-coated balloons, have significantly reduced restenosis rates, they remain limited by delayed vascular healing, chronic inflammation, and late adverse events. These limitations reflect a fundamental mismatch between current device pharmacology, which relies on nonselective antiproliferative drugs, and the highly coordinated, cell-specific programs that orchestrate vascular repair. Extracellular vesicles (EVs), nanometer-scale membrane-bound particles secreted by virtually all cell types, provide a biologically evolved platform for intercellular communication and cargo delivery. In the cardiovascular system, EVs regulate endothelial regeneration, smooth muscle cell phenotype, extracellular matrix remodeling, and macrophage polarization through precisely orchestrated combinations of miRNA, proteins, and lipids. Here, we synthesize mechanistic insights into EV biogenesis, cargo selection, recruitment, and functional effects in vascular healing and inflammation and translate these into a formal framework for EV-inspired device engineering. We discuss how EV-based or EV-mimetic coatings can be designed to sense the local microenvironment, deliver encoded biological “instruction sets,” and function within ECM-mimetic scaffolds to couple local stent healing with systemic tissue repair. Finally, we outline the manufacturing, regulatory, and clinical trial issues that must be addressed for EV-inspired cardiovascular devices to transition from proof of concept to clinical reality. By shifting the focus from pharmacological suppression to biological regulation of healing, EV-based strategies offer a path to resolve the long-standing tradeoff between restenosis prevention and durable vascular healing. Full article

Cardiovascular diseases (CVDs) have emerged as a common health problem. However, despite their prevalence, little progress has been made in their treatment. In recent years, neurotrophic factors (NTFs) have been discovered to exert cardioprotective functions for CVDs. NTFs can modulate vascular integrity, myocardial remodeling, angiogenesis, and autonomic regulation, playing the roles of maintaining cardiovascular homeostasis and influencing disease progression. Under pathological conditions, the supplement of NTFs can induce substantial adaptations to mitigate adverse cardiac responses. Several NTFs have been investigated in this regard. This review briefly elaborates on present insights into the expression, signaling pathways, and regulatory effects of NTFs on the development of CVDs, and also discusses emerging therapeutic strategies based on NTFs, ranging from exercise to advanced modalities including stem cell therapy, gene transfer, recombinant protein therapy and NTF mimetics, among which the mimetics and exercise interventions emerge as the most promising avenues for clinical translation. Full article

To address the challenges in wound healing, clinical management increasingly demands targeted, adaptive, responsive, and patient-centered strategies. This is especially true for wounds characterized by delayed healing and a high risk of infection. Advances in regenerative medicine and biomaterial technologies are fostering the development of multifunctional approaches that integrate tissue regeneration, antibacterial/antibiofilm activity, immunomodulation, and real-time monitoring. This paper surveys emerging platforms, including both natural and synthetic scaffolds, hydrogels enriched with platelet-derived growth factors, glycosaminoglycan mimetics, bioactive peptides (such as GHK-Cu and antimicrobial peptides), nanoscaffolds, and stimuli-responsive systems. The paper also explores cutting-edge technologies such as water-powered, electronics-free dressings that deliver localized electrical stimulation; biodegradable bioelectric sutures that produce self-sustained mechano-electrical signals; and sensory bandages that monitor pH, moisture, temperature, and bacterial contamination in real-time while enabling on-demand drug release with pro-regenerative, antibacterial, and other therapeutic functionalities. Further therapeutic approaches include natural matrices, exosomes, gene editing, 3D bioprinting, and AI-assisted design. Particular attention is paid to orthopedic applications and orthopedic implant infection. A brief section addresses the still unresolved challenge of articular cartilage regeneration. Interdisciplinary innovation, integrating insights from molecular biology through engineering, plays a central role in translating novel strategies into tailored, clinically effective wound management solutions. Full article

Background: Respiratory syncytial virus (RSV) is one of the leading causes of lower respiratory tract illness and hospitalizations in children aged ≤5 years worldwide. The aim of this study was to characterize the Polish population of patients aged ≤5 years who were hospitalized due to RSV infection, focusing on their clinical and epidemiological characteristics as well as treatment patterns. Methods: This retrospective observational study was conducted between November 2023 and February 2024 in 41 hospitals with pediatric departments across Poland. Data from patients aged ≤5 years admitted due to RSV infection confirmed with antigen test or RT-PCR were collected. The dataset was weighted and extrapolated to allow conclusions applicable to the general population of patients aged 0–5 years hospitalized with RSV infection in Poland. Results: Data from 419 patients were analyzed. Over half (57.4%) were younger than 12 months, 84% were born at term, and 85.8% had no comorbidities. The most frequent manifestations of RSV infections were pneumonia (56.8%), bronchiolitis (35.9%), and bronchitis (12.4%). Viral co-infections were identified in 8% of patients. Regarding treatment, 21.1% of patients required respiratory support, 67.6% received inhaled steroid therapy, 61.5% were treated with antibiotics, 48.1% received beta2-mimetics and anticholinergics, and 44.3% underwent systemic steroid therapy. Conclusions: Our findings confirm that severe RSV primarily affects the youngest children with no comorbidities who do not present high risk conditions. To reduce the overall disease burden, preventive strategies should be offered to all children, not being limited to those in risk groups. Full article

Determining the drivers of phenotypic evolution and their role on shaping regional phenotypic diversity is a fundamental aspect of mimicry research. Beetles of the genus Ceroglossus are well known for their rampant color diversity, and species have been shown to exhibit convergence in elytral coloration when in sympatry. Despite solid phylogenetic evidence showing that color convergence is not the result of shared ancestry, more direct evidence of the role of selection on color evolution is lacking. In this study, we used two different, but complementary approaches to test whether selection plays a role in color divergence and whether predators are responsible for its maintenance. We first used molecular data to assess gene flow. Subsequently, we used the sequence data to conduct coalescent simulations and generate expectations for color fixation under the hypothesis of genetic drift. Second, we conducted field experiments to test whether predators exhibited different preferences on mimetic versus non-mimetic phenotypes. Results from the coalescent simulations showed that color fixation exhibited strong deviations from the genetic drift expectation, implying that selection must be responsible for color divergence. Field experiments showed that translocated beetles (into areas where they were not mimics) suffered higher rates of attacks than those beetles that mimicked the locally abundant phenotypes. Thus, our study supports the hypothesis of selection as a driving force of color evolution in Ceroglossus beetles and provides the context that explains and supports previous claims of Müllerian mimicry. Full article

Atherosclerosis, a leading cause of cardiovascular disease, is driven by a complex interplay of dyslipidemia, inflammation, and arterial plaque formation and progression. Animal models are indispensable to elucidate the pathogenesis and develop novel therapies. Rodent models are widely utilized due to their cost-effectiveness, reproducibility, and rapid disease progression. However, notable species differences exist in lipoprotein composition and lipid metabolism pathways. Mice and rats exhibit an HDL-dominant profile, whereas Syrian golden hamsters express cholesteryl ester transfer protein (CETP) and display a higher LDL fraction, but lower than that of humans, offering a model closer to human metabolically. Divergent CETP activity across species further complicates the translational relevance of the findings from these models for atherosclerosis and related metabolic disorders. This review systematically examines the key factors in rodent model selection and optimization, with consideration on the roles of sex and age. We focus on three commonly used and well-characterized rodent strains prone to atherosclerosis: C57BL/6J mice, Sprague-Dawley (SD) rats, Wistar rats, and golden hamsters. On Apoe^−/− or Ldlr^−/− backgrounds, male C57BL/6 mice, owing to their pronounced hypercholesterolemia and extended survival with high-fat diet, are preferentially used in late-stage plaque stability studies. In contrast, male SD or Wistar rats develop atherosclerosis slowly with limited lesion progression, while hamsters, despite their human-like lipid metabolism, exhibit substantial individual variability and lesions that typically arrest at early fatty streaks with poor reproducibility. Therefore, rats and hamsters are better suited for studies focusing on early disease mechanisms and human-mimetic lipid metabolism. Full article

Biomolecule–photosensitizer conjugates have rapidly evolved into one of the most powerful strategies for improving the selectivity, efficacy, and translational potential of photodynamic therapy (PDT). By integrating photosensitizers (PSs) with carbohydrates, amino acids, peptides, aptamers, proteins, cofactors, vitamins or antibodies, these constructs overcome long-standing limitations of classical PDT, including poor solubility, insufficient tumour accumulation, and strong dependence on oxygen availability. Beyond enhancing receptor-mediated uptake and enabling precise interactions with the tumour microenvironment (TME), bioconjugation also modulates aggregation, photochemical properties, intracellular accumulation, and immune system activation. A particularly transformative trend is the emergence of supramolecular architectures in which photosensitizers form defined nanostructured aggregates with peptides or proteins. Once considered an undesirable phenomenon, aggregation is now recognized as a tenable feature that governs photochemical behaviour. Engineered aggregates can undergo environment-triggered disassembly to monomeric, photoactive states, or operate as semiconductor-like nanodomains capable of Type I reaction through symmetry-breaking charge separation. This shift toward oxygen-independent radical pathways offers a promising solution to the challenge of hypoxia, a hallmark of the TME that severely compromises conventional Type II PDT. Parallel advances in 3D experimental platforms such as tumour organoids and organ-on-chip systems provide physiologically relevant validation of these conjugates, enabling the assessment of penetration, subcellular localization, immunogenic cell death, and therapeutic synergy within realistic TME conditions. Collectively, the integration of biomolecular targeting with controlled supramolecular design is redefining the landscape of PDT. Future progress will depend on designing conjugates that retain high activity under hypoxia, engineering dynamic aggregate states, and systematically validating these systems in advanced TME-mimetic models. Together, these developments position biomolecule–photosensitizer conjugates as a versatile and increasingly less oxygen-dependent class of next-generation phototherapeutic agents. Full article