Exosome biopotentiated hydrogel restores damaged skeletal muscle in a porcine model of stress urinary incontinence

Topical Platelet Exosomes Reduce Senescence Signaling in Human Skin: An Exploratory Prospective Trial

BACKGROUND

Cellular senescence, an irreversible cell cycle arrest with secretory phenotype, is a hallmark of skin aging. Regenerative exosome-based approaches, such as topical human platelet extract (HPE), are emerging to target age-related skin dysfunction.

OBJECTIVE

To evaluate the cellular and molecular effects of topical HPE for skin rejuvenation after 12 weeks of twice daily use.

METHODS

Skin biopsies were obtained for histological evaluation of senescence markers, p16INK4a and p21CIP1/WAF1. Telomere-associated foci, coassociation of telomeres, and DNA damage marker, γH2AX, were assessed. RNA sequencing evaluated senescence associated secretory phenotype (SASP) and extracellular matrix pathways.

RESULTS

p16INK4a and p21CIP1/WAF1 staining in senescent skin cells revealed low and high expression subgroups that did not correspond to chronological age. Topical HPE significantly reduced high p16INK4a cells in the dermis (p = .02). There was also a decrease in telomere damage after topical HPE (p = .03). In patients with high senescent cells at baseline, there was a 40% reduction in proinflammatory SASP. Extracellular matrix remodeling pathways, including collagen and elastic fibers, were up-regulated.

CONCLUSION

Topical HPE, applied on intact skin, reduced senescence signaling and senescence-associated telomere damage after 12 weeks of twice daily use, targeting a path for skin longevity or healthy skin aging.

Animal models, treatment options, and biomaterials for female stress urinary incontinence

In the quest to tackle stress urinary incontinence (SUI), the synthesis of cutting-edge biomaterials and regenerative materials has emerged as a promising frontier. Briefly, animal models like vaginal distension and bilateral ovariectomy serve as crucial platforms for unraveling the intricacies of SUI, facilitating the evaluation of innovative treatments. The spotlight, however, shines on the development and application of novel biomaterials-ranging from urethral bulking agents to nano-gel composites-which aim to bolster urethral support and foster tissue regeneration. Furthermore, the exploration of stem cell therapies, particularly those derived from adipose tissues and urine, heralds a new era of regenerative medicine, offering potential for significant improvements in urinary function. This review encapsulates the progress in biomaterials and regenerative strategies, highlighting their pivotal role in advancing the treatment of SUI, thereby opening new avenues for effective and minimally invasive solutions.

Hydrogel-exosome system in tissue engineering: A promising therapeutic strategy

Characterized by their pivotal roles in cell-to-cell communication, cell proliferation, and immune regulation during tissue repair, exosomes have emerged as a promising avenue for "cell-free therapy" in clinical applications. Hydrogels, possessing commendable biocompatibility, degradability, adjustability, and physical properties akin to biological tissues, have also found extensive utility in tissue engineering and regenerative repair. The synergistic combination of exosomes and hydrogels holds the potential not only to enhance the efficiency of exosomes but also to collaboratively advance the tissue repair process. This review has summarized the advancements made over the past decade in the research of hydrogel-exosome systems for regenerating various tissues including skin, bone, cartilage, nerves and tendons, with a focus on the methods for encapsulating and releasing exosomes within the hydrogels. It has also critically examined the gaps and limitations in current research, whilst proposed future directions and potential applications of this innovative approach.

Exosomes based strategies for cardiovascular diseases: Opportunities and challenges

Exosomes, as nanoscale extracellular vesicles (EVs), are secreted by all types of cells to facilitate intercellular communication in living organisms. After being taken up by neighboring or distant cells, exosomes can alter the expression levels of target genes in recipient cells and thereby affect their pathophysiological outcomes depending on payloads encapsulated therein. The functions and mechanisms of exosomes in cardiovascular diseases have attracted much attention in recent years and are thought to have cardioprotective and regenerative potential. This review summarizes the biogenesis and molecular contents of exosomes and details the roles played by exosomes released from various cells in the progression and recovery of cardiovascular disease. The review also discusses the current status of traditional exosomes in cardiovascular tissue engineering and regenerative medicine, pointing out several limitations in their application. It emphasizes that some of the existing emerging industrial or bioengineering technologies are promising to compensate for these shortcomings, and the combined application of exosomes and biomaterials provides an opportunity for mutual enhancement of their performance. The integration of exosome-based cell-free diagnostic and therapeutic options will contribute to the further development of cardiovascular regenerative medicine.

Nebulized platelet-derived extracellular vesicles attenuate chronic cigarette smoke-induced murine emphysema

Chronic obstructive pulmonary disease (COPD) is a prevalent lung disease usually resulting from cigarette smoking (CS). Cigarette smoking induces oxidative stress, which causes inflammation and alveolar epithelial cell apoptosis and represents a compelling therapeutic target for COPD. Purified human platelet-derived exosome product (PEP) is endowed with antioxidant enzymes and immunomodulatory molecules that mediate tissue repair. In this study, a murine model of CS-induced emphysema was used to determine whether nebulized PEP can influence the development of CS-induced emphysema through the mitigation of oxidative stress and inflammation in the lung. Nebulization of PEP effectively delivered the PEP vesicles into the alveolar region, with evidence of their uptake by type I and type II alveolar epithelial cells and macrophages. Lung function testing and morphometric assessment showed a significant attenuation of CS-induced emphysema in mice treated with nebulized PEP thrice weekly for 4 weeks. Whole lung immuno-oncology RNA sequencing analysis revealed that PEP suppressed several CS-induced cell injuries and inflammatory pathways. Validation of inflammatory cytokines and apoptotic protein expression on the lung tissue revealed that mice treated with PEP had significantly lower levels of S100A8/A9 expressing macrophages, higher levels of CD4+/FOXP3+ Treg cells, and reduced NF-κB activation, inflammatory cytokine production, and apoptotic proteins expression. Further validation using in vitro cell culture showed that pretreatment of alveolar epithelial cells with PEP significantly attenuated CS extract-induced apoptotic cell death. These data show that nebulization of exosomes like PEP can effectively deliver exosome cargo into the lung, mitigate CS-induced emphysema in mice, and suppress oxidative lung injury, inflammation, and apoptotic alveolar epithelial cell death.

Exosome Therapy for a Nonhealing Scalp Wound Following Chemoradiation and Surgical Therapy

This case report describes the safety and utility of a noninvasive therapy, Purified Exosome Product (PEP), for poorly healing scalp wounds in the setting of prior chemoradiation and surgery. A man in his 60s with a history of high-grade angiosarcoma of the right temporoparietal scalp reconstruction had a 1-year history of 2 nonhealing scalp wounds after neoadjuvant chemotherapy followed by concurrent chemoradiation therapy, wide local excision, and latissimus dorsi free flap and split-thickness skin graft. The patient underwent débridement followed by 4 collagen (Bellafill)-PEP and 4 fibrin (Tisseel)-PEP applications during 7 months in 2022. Photographs of the area of exposed bone of the temporoparietal wound were measured and standardized by ImageJ open-source software. The frontal wound was not routinely measured and therefore was qualitatively assessed by reviewing photographs over time. The frontal wound completely healed, and the temporoparietal wound showed a 96% decrease in overall size. The patient had no adverse effects of treatment and continues to demonstrate ongoing healing. This case exhibits the safety and utility of topical PEP therapy for noninvasive treatment of poorly healing scalp wounds and offers the potential for an alternative treatment of patients who are poor candidates for additional surgical intervention.

HB-EGF-loaded nanovesicles enhance trophectodermal spheroid attachment and invasion

The ability of trophectodermal cells (outer layer of the embryo) to attach to the endometrial cells and subsequently invade the underlying matrix are critical stages of embryo implantation during successful pregnancy establishment. Extracellular vesicles (EVs) have been implicated in embryo-maternal crosstalk, capable of reprogramming endometrial cells towards a pro-implantation signature and phenotype. However, challenges associated with EV yield and direct loading of biomolecules limit their therapeutic potential. We have previously established generation of cell-derived nanovesicles (NVs) from human trophectodermal cells (hTSCs) and their capacity to reprogram endometrial cells to enhance adhesion and blastocyst outgrowth. Here, we employed a rapid NV loading strategy to encapsulate potent implantation molecules such as HB-EGF (NVHBEGF). We show these loaded NVs elicit EGFR-mediated effects in recipient endometrial cells, activating kinase phosphorylation sites that modulate their activity (AKT S124/129, MAPK1 T185/Y187), and downstream signalling pathways and processes (AKT signal transduction, GTPase activity). Importantly, they enhanced target cell attachment and invasion. The phosphoproteomics and proteomics approach highlight NVHBEGF-mediated short-term signalling patterns and long-term reprogramming capabilities on endometrial cells which functionally enhance trophectodermal-endometrial interactions. This proof-of-concept study demonstrates feasibility in enhancing the functional potency of NVs in the context of embryo implantation.

Rapid generation of functional nanovesicles from human trophectodermal cells for embryo attachment and outgrowth

Extracellular vesicles (EVs) are important mediators of embryo attachment and outgrowth critical for successful implantation. While EVs have garnered immense interest in their therapeutic potential in assisted reproductive technology by improving implantation success, their large-scale generation remains a major challenge. Here, we report a rapid and scalable production of nanovesicles (NVs) directly from human trophectoderm cells (hTSCs) via serial mechanical extrusion of cells; these NVs can be generated in approximately 6 h with a 20-fold higher yield than EVs isolated from culture medium of the same number of cells. NVs display similar biophysical traits (morphologically intact, spherical, 90-130 nm) to EVs, and are laden with hallmark players of implantation that include cell-matrix adhesion and extracellular matrix organisation proteins (ITGA2/V, ITGB1, MFGE8) and antioxidative regulators (PRDX1, SOD2). Functionally, NVs are readily taken up by low-receptive endometrial HEC1A cells and reprogram their proteome towards a receptive phenotype that support hTSC spheroid attachment. Moreover, a single dose treatment with NVs significantly enhanced adhesion and spreading of mouse embryo trophoblast on fibronectin matrix. Thus, we demonstrate the functional potential of NVs in enhancing embryo implantation and highlight their rapid and scalable generation, amenable to clinical utility.

Regenerative Medicine in Urogynecology: Where We Are and Where We Want to Be

ABSTRACT

Pelvic floor disorders (PFDs) constitute a major public health issue given their negative effect on quality of life for millions of women worldwide and the associated economic burden. As the prevalence of PFDs continues to increase, novel therapeutic approaches for the effective treatment of these disorders are urgently needed. Regenerative medicine techniques, including cellular therapies, extracellular vesicles, secretomes, platelet-rich plasma, laser therapy, and bioinductive acellular biomaterial scaffolds, are emerging as viable clinical options to counteract urinary and fecal incontinence, as well as pelvic organ prolapse. This brief expert review explores the current state-of-science regarding application of these therapies for the treatment of PFDs. Although regenerative approaches have not been widely deployed in clinical care to date, these innovative techniques show a promising safety profile and potential to positively affect the quality of life of patients with PFDs. Furthermore, investigations focused on regeneration of the main constituents of the pelvic floor and lower urinary tract improve our understanding of the underlying pathophysiology of PFDs. Regenerative medicine techniques have a high potential not only to revolutionize treatment of PFDs but also to prevent these complex conditions.

Pulmonary Biodistribution of Platelet-Derived Regenerative Exosomes in a Porcine Model

The purpose of this study was to evaluate the biodistribution of a platelet-derived exosome product (PEP), previously shown to promote regeneration in the setting of wound healing, in a porcine model delivered through various approaches. Exosomes were labeled with DiR far-red lipophilic dye to track and quantify exosomes in tissue, following delivery via intravenous, pulmonary artery balloon catheter, or nebulization in sus scrofa domestic pigs. Following euthanasia, far-red dye was detected by Xenogen IVUS imaging, while exosomal protein CD63 was detected by Western blot and immunohistochemistry. Nebulization and intravenous delivery both resulted in global uptake of exosomes within the lung parenchyma. However, nebulization resulted in the greatest degree of exosome uptake. Pulmonary artery balloon catheter-guided delivery provided the further ability to localize pulmonary delivery. No off-target absorption was noted in the heart, spleen, or kidney. However, the liver demonstrated uptake primarily in nebulization-treated animals. Nebulization also resulted in uptake in the trachea, without significant absorption in the esophagus. Overall, this study demonstrated the feasibility of pulmonary delivery of exosomes using nebulization or intravenous infusion to accomplish global delivery or pulmonary artery balloon catheter-guided delivery for localized delivery.

Reconstituted Extracellular Vesicles from Human Platelets Decrease Viral Myocarditis in Mice

Patients with viral myocarditis are at risk of sudden death and may progress to dilated cardiomyopathy (DCM). Currently, no disease-specific therapies exist to treat viral myocarditis. Here it is examined whether reconstituted, lyophilized extracellular vesicles (EVs) from platelets from healthy men and women reduce acute or chronic myocarditis in male mice. Human-platelet-derived EVs (PEV) do not cause toxicity, damage, or inflammation in naïve mice. PEV administered during the innate immune response significantly reduces myocarditis with fewer epidermal growth factor (EGF)-like module-containing mucin-like hormone receptor-like 1 (F4/80) macrophages, T cells (cluster of differentiation molecules 4 and 8, CD4 and CD8), and mast cells, and improved cardiac function. Innate immune mediators known to increase myocarditis are decreased by innate PEV treatment including Toll-like receptor (TLR)4 and complement. PEV also significantly reduces perivascular fibrosis and remodeling including interleukin 1 beta (IL-1β), transforming growth factor-beta 1, matrix metalloproteinase, collagen genes, and mast cell degranulation. PEV given at days 7-9 after infection reduces myocarditis and improves cardiac function. MicroRNA (miR) sequencing reveals that PEV contains miRs that decrease viral replication, TLR4 signaling, and T-cell activation. These data show that EVs from the platelets of healthy individuals can significantly reduce myocarditis and improve cardiac function.

Advances of exosomes-based applications in diagnostic biomarkers for dental disease and dental regeneration

Exosomes are produced by all the cells and exist in all body fluids. They have been regarded as potentially promising to diagnostic biomarkers and therapeutic bioactive mediators since they transport DNA, RNA and protein information from cell to cell. Herein, we summarized the recent research about exosomes from gingival crevicular fluid, saliva and serum used as diagnostic markers in periodontitis and dental caries. Moreover, we highlighted the mechanisms of exosomes in dental pulp regeneration and periodontal regeneration, as well as the technological innovation of exosome delivery methods in oral disease. In the end, this review discussed the advantages and future challenges of exosomes in real clinical applications.

A Ready-to-Use Purified Exosome Product for Volumetric Muscle Loss and Functional Recovery

Large skeletal muscle defects owing to trauma or following tumor extirpation can result in substantial functional impairment. Purified exosomes are now available clinically and have been used for wound healing. The objective of this study was to evaluate the regenerative capacity of commercially available exosomes on an animal model of volumetric muscle loss (VML) and its potential translation to human muscle injury. An established VML rat model was used. In the in vitro experiment, rat myoblasts were isolated and cocultured with 5% purified exosome product (PEP) to validate uptake. Myoblast proliferation and migration was evaluated with increasing concentrations of PEP (2.5%, 5%, and 10%) in comparison with control media (F10) and myoblast growth medium (MGM). In the in vivo experiment, a lateral gastrocnemius-VML defect was made in the rat hindlimb. Animals were randomized into four experimental groups; defects were treated with surgery alone, fibrin sealant, fibrin sealant and PEP, or platelet-rich plasma (PRP). The groups were further randomized into four recovery time points (14, 28, 45, or 90 days). The isometric tetanic force (ITF), which was measured as a percentage of force compared with normal limb, was used for functional evaluation. Florescence microscopy confirmed that 5% PEP demonstrated cellular uptake ∼8-12 h. Compared with the control, myoblasts showed faster proliferation with PEP irrespective of concentration. PEP concentrations of 2.5% and 5% promoted myoblast migration faster compared with the control (<0.05). At 90 days postop, both the PEP and fibrin sealant and PRP groups showed greater ITF compared with control and fibrin sealant alone (<0.05). At 45 days postop, PEP with fibrin sealant had greater cellularity compared with control (<0.05). At 90 days postop, both PEP with fibrin sealant and the PRP-treated groups had greater cellularity compared with fibrin sealant and control (<0.05). PEP promoted myoblast proliferation and migration. When delivered to a wound with a fibrin sealant, PEP allowed for muscle regeneration producing greater functional recovery and more cellularity in vivo compared with untreated animals. PEP may promote muscle regeneration in cases of VML; further research is warranted to evaluate PEP for the treatment of clinical muscle defects.