Hydrogel-mediated delivery of platelet-derived exosomes: Innovations in tissue engineering

Exosomes in Regulating miRNAs for Biomarkers of Neurodegenerative Disorders

Exosomal proteins and miRNAs, including α-synuclein, Aβ, tau, CXCL12, miR-24, and miR-23b-3p, are emerging as valuable biomarkers for Parkinson's disease and prenatal diagnostics, with significant potential for personalized therapies. Advances in MRI and chitosan-based drug delivery systems are creating new opportunities for diagnosing and treating neurodegenerative disorders. Exosomes regulate miRNAs and proteins, presenting theranostic potential for Alzheimer's and Huntington's diseases, yet facing delivery and targeting challenges. Exosomal miRNAs, such as miR-1234, miR-5678, and miR-29a, are crucial for the early detection and monitoring of the progression of neurodegenerative diseases. Additionally, novel biomarkers such as SCA27B and FGF14 gene mutations and serum miR-455-3p offer promising noninvasive diagnostic methods for Alzheimer's disease. The expanding role of exosome-derived miRNAs in targeting oncogenes and regulating the cell cycle enhances therapeutic strategies for neurological disorders, opening doors to more personalized and effective disease management.

Platelet-derived extracellular vesicles: emerging players in hemostasis and thrombosis

Platelets, long recognized for their role in hemostasis and thrombosis, have emerged as key players in a wide array of physiological and pathological processes through the release of platelet-derived extracellular vesicles (PEVs). These nanoscale vesicles, rich in bioactive molecules such as proteins, lipids, and nucleic acids, facilitate intercellular communication and influence processes ranging from angiogenesis and inflammation to immune modulation and tissue repair. PEVs, the most abundant extracellular vesicles in circulation, display procoagulant activity 50-100 times greater than activated platelets, underscoring their pivotal role in hemostasis and thrombosis. Recent research has unveiled their dual role in health and disease, highlighting their potential as diagnostic biomarkers and therapeutic vehicles. PEVs are implicated in cancer progression, autoimmune diseases, and infectious diseases, where they modulate tumor microenvironments, immune responses, and inflammatory pathways. Moreover, their ability to deliver therapeutic agents with high specificity and biocompatibility positions them as promising tools in regenerative medicine, drug delivery, and targeted therapies. This review comprehensively explores PEV biogenesis, cargo composition, and their multifaceted roles in hemostasis and thrombosis, as well as their broader implications in disease. It also explores the potential of PEVs as diagnostic markers and innovative therapeutic strategies, offering insights into their application in treating thrombotic disorders, cancer, and inflammatory diseases. Despite significant advancements, challenges remain in standardizing isolation protocols and translating preclinical findings into clinical applications. Unlocking the full potential of PEVs promises to revolutionize diagnostics and therapeutics, paving the way for novel approaches to managing complex diseases.

Beyond Blood Clotting: The Many Roles of Platelet-Derived Extracellular Vesicles

Platelet-derived extracellular vesicles (pEVs) are emerging as pivotal players in numerous physiological and pathological processes, extending beyond their traditional roles in hemostasis and thrombosis. As one of the most abundant vesicle types in human blood, pEVs transport a diverse array of bioactive molecules, including growth factors, cytokines, and clotting factors, facilitating crucial intercellular communication, immune regulation, and tissue healing. The unique ability of pEVs to traverse tissue barriers and their biocompatibility position them as promising candidates for targeted drug delivery and regenerative medicine applications. Recent studies have underscored their involvement in cancer progression, viral infections, wound healing, osteoarthritis, sepsis, cardiovascular diseases, rheumatoid arthritis, and atherothrombosis. For instance, pEVs promote tumor progression and metastasis, enhance tissue repair, and contribute to thrombo-inflammation in diseases such as COVID-19. Despite their potential, challenges remain, including the need for standardized isolation techniques and a comprehensive understanding of their mechanisms of action. Current research efforts are focused on leveraging pEVs for innovative anti-cancer treatments, advanced drug delivery systems, regenerative therapies, and as biomarkers for disease diagnosis and monitoring. This review highlights the necessity of overcoming technical hurdles, refining isolation methods, and establishing standardized protocols to fully unlock the therapeutic potential of pEVs. By understanding the diverse functions and applications of pEVs, we can advance their use in clinical settings, ultimately revolutionizing treatment strategies across various medical fields and improving patient outcomes.

Advances and Challenges in Immune-Modulatory Biomaterials for Wound Healing Applications

Wound healing progresses through three distinct stages: inflammation, proliferation, and remodeling. Immune regulation is a central component throughout, crucial for orchestrating inflammatory responses, facilitating tissue repair, and restraining scar tissue formation. Elements such as mitochondria, reactive oxygen species (ROS), macrophages, autophagy, ferroptosis, and cytokines collaboratively shape immune regulation in this healing process. Skin wound dressings, recognized for their ability to augment biomaterials' immunomodulatory characteristics via antimicrobial, antioxidative, pro- or anti-inflammatory, and tissue-regenerative capacities, have garnered heightened attention. Notwithstanding, a lack of comprehensive research addressing how these dressings attain immunomodulatory properties and the mechanisms thereof persists. Hence, this paper pioneers a systematic review of biomaterials, emphasizing immune regulation and their underlying immunological mechanisms. It begins by highlighting the importance of immune regulation in wound healing and the peculiarities and obstacles faced in skin injury recovery. This segment explores the impact of wound metabolism, infections, systemic illnesses, and local immobilization on the immune response during healing. Subsequently, the review examines a spectrum of biomaterials utilized in skin wound therapy, including hydrogels, aerogels, electrospun nanofiber membranes, collagen scaffolds, microneedles, sponges, and 3D-printed constructs. It elaborates on the immunomodulatory approaches employed by these materials, focusing on mitochondrial and ROS modulation, autophagic processes, ferroptosis, macrophage modulation, and the influence of cytokines on wound healing. Acknowledging the challenge of antibiotic resistance, the paper also summarizes promising plant-based alternatives for biomaterial integration, including curcumin. In its concluding sections, the review charts recent advancements and prospects in biomaterials that accelerate skin wound healing via immune modulation. This includes exploring mitochondrial transplantation materials, biomaterial morphology optimization, metal ion incorporation, electrostimulation-enabled immune response control, and the benefits of composite materials in immune-regulatory wound dressings. The ultimate objective is to establish a theoretical foundation and guide future investigations in the realm of skin wound healing and related materials science disciplines.

F127-SE-tLAP thermosensitive hydrogel alleviates bleomycin-induced skin fibrosis via TGF-β/Smad pathway

BACKGROUND

Skin fibrosis affects the normal function of the skin. TGF-β1 is a key cytokine that affects organ fibrosis. The latency-associated peptide (LAP) is essential for TGF-β1 activation. We previously constructed and prepared truncated LAP (tLAP), and confirmed that tLAP inhibited liver fibrosis by affecting TGF-β1. SPACE peptide has both transdermal and transmembrane functions. SPACE promotes the delivery of macromolecules through the stratum corneum into the dermis. This study aimed to alleviate skin fibrosis through the delivery of tLAP by SPACE.

METHODS

The SPACE-tLAP (SE-tLAP) recombinant plasmid was constructed. SE-tLAP was purified by nickel affinity chromatography. The effects of SE-tLAP on the proliferation, migration, and expression of fibrosis-related and inflammatory factors were evaluated in TGF-β1-induced NIH-3T3 cells. F127-SE-tLAP hydrogel was constructed by using F127 as a carrier to load SE-tLAP polypeptide. The degradation, drug release, and biocompatibility of F127-SE-tLAP were evaluated. Bleomycin was used to induce skin fibrosis in mice. HE, Masson, and immunohistochemistry were used to observe the skin histological characteristics.

RESULTS

SE-tLAP inhibited the proliferation, migration, and expression of fibrosis-related and inflammatory factors in NIH-3T3 cells. F127-SE-tLAP significantly reduced ECM production, collagen deposition, and fibrotic pathological changes, thereby alleviating skin fibrosis.

CONCLUSION

F127-SE-tLAP could increase the transdermal delivery of LAP, reduce the production and deposition of ECM, inhibit the formation of dermal collagen fibers, and alleviate the progression of skin fibrosis. It may provide a new idea for the therapy of skin fibrosis.