Effects of Adipose-Derived Stem Cells and Platelet-Rich Plasma Exosomes on The Inductivity of Hair Dermal Papilla Cells

Therapeutic Potential of Extracellular Vesicles (Exosomes) Derived From Platelet-Rich Plasma: A Literature Review

BACKGROUND

There are exciting advances in the field of exosomes research as a potential regenerative therapy. Platelet-rich plasma represents an abundant source of exosomes.

AIM

To present evidence on the use of platelet-rich plasma-derived exosomes in dermatology and discuss current technical limitations.

METHODS

A literature search was conducted using Embase (Ovid), Web of Science, and ClinicalTrials.gov in June 2024.

RESULTS

Platelet-rich plasma-derived exosomes contain a myriad of growth factors, genetic materials, and lipids that mediate paracrine signaling. Several preclinical studies have demonstrated their potential in wound healing. This includes faster wound contraction in diabetic animal models, as well as enhanced angiogenesis, increased cell proliferation and migration, and protection against hyperglycemic conditions in vitro. A case study reported a topical platelet-derived exosome product tried successfully in a patient with persistent scalp wounds. In contrast, there is scarce information on the use of platelet-rich plasma-derived exosomes in hair growth and skin rejuvenation. Isolation techniques, activation methods, and methods of delivery have not been optimized, which warrants further research. Novel delivery methods, such as hydrogel-based preparations, may enable the topical application of exosomes.

CONCLUSION

Exosomes derived from platelet-rich plasma have demonstrated therapeutic potential. More research is needed to standardize its use.

Exosomes derived from platelet-rich plasma present a novel potential in repairing knee articular cartilage defect combined with cyclic peptide-modified β-TCP scaffold

BACKGROUND

The aim of this study was to investigate the therapeutic effects and mechanisms of PRP-exos combined with cyclic peptide-modified β-TCP scaffold in the treatment of rabbit knee cartilage defect.

METHODS

PRP-exos were extracted and characterized by TEM, NTA and WB. The therapeutic effects were evaluated by ICRS score, HE staining, Immunohistochemistry, qRT-PCR and ELISA. The repair mechanism of PRP-exos was estimated and predicted by miRNA sequencing analysis and protein-protein interaction network analysis.

RESULTS

The results showed that PRP-exos had a reasonable size distribution and exhibited typical exosome morphology. The combination of PRP-exos and cyclic peptide-modified β-TCP scaffold improved ICRS score and the expression level of COL-2, RUNX2, and SOX9. Moreover, this combination therapy reduced the level of MMP-3, TNF-α, IL-1β, and IL-6, while increasing the level of TIMP-1. In PRP-exos miRNA sequencing analysis, the total number of known miRNAs aligned across all samples was 252, and a total of 91 differentially expressed miRNAs were detected. The results of KEGG enrichment analysis and the protein-protein interaction network analysis indicated that the PI3K/AKT signaling pathway could impact the function of chondrocytes by regulating key transcription factors to repair cartilage defect.

CONCLUSION

PRP-exos combined with cyclic peptide-modified β-TCP scaffold effectively promoted cartilage repair and improved chondrocyte function in rabbit knee cartilage defect. Based on the analysis and prediction of PRP-exos miRNAs sequencing, PI3K/AKT signaling pathway may contribute to the therapeutic effect. These findings provide experimental evidence for the application of PRP-exos in the treatment of cartilage defect.

Improvement of androgenic alopecia by extracellular vesicles secreted from hyaluronic acid-stimulated induced mesenchymal stem cells

BACKGROUND

Androgenetic alopecia (AGA) is a common form of hair loss. Androgens, such as testosterone and dihydrotestosterone, are the main causes of AGA. Extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) can reduce AGA. However, preparing therapeutic doses of MSCs for clinical use is challenging. Induced pluripotent stem cell-derived MSCs (iMSCs) are homogenous and easily expandable, enabling scalable production of EVs. Hyaluronic acid (HA) can exert various functions including free radical scavenging, immune regulation, and cell migration. Herein, we examined whether hyaluronic acid (HA) stimulation of iMSCs could produce EVs with enhanced therapeutic outcomes for AGA.

METHODS

EVs were collected from iMSCs primed with HA (HA-iMSC-EVs) or without HA (iMSC-EVs). The characteristics of EVs were examined using dynamic light scattering, cryo-transmission electron microscopy, immunoblotting, flow cytometry, and proteomic analysis. In vitro, we compared the potential of EVs in stimulating the survival of hair follicle dermal papilla cells undergoing testosterone-mediated AGA. Additionally, the expression of androgen receptor (AR) and relevant growth factors as well as key proteins of Wnt/β-catenin signaling pathway (β-catenin and phosphorylated GSK3β) was analyzed. Subsequently, AGA was induced in male C57/BL6 mice by testosterone administration, followed by repeated injections of iMSC-EVs, HA-iMSC-EVs, finasteride, or vehicle. Several parameters including hair growth, anagen phase ratio, reactivation of Wnt/β-catenin pathway, and AR expression was examined using qPCR, immunoblotting, and immunofluorescence analysis.

RESULTS

Both types of EVs showed typical characteristics for EVs, such as size distribution, markers, and surface protein expression. In hair follicle dermal papilla cells, the mRNA levels of AR, TGF-β, and IL-6 increased by testosterone was blocked by HA-iMSC-EVs, which also contributed to the augmented expression of trophic genes related to hair regrowth. However, no notable changes were observed in the iMSC-EVs. Re-activation of Wnt/β-catenin was observed in HA-iMSC-EVs but not in iMSC-EVs, as shown by β-catenin stabilization and an increase in phosphorylated GSK3β. Restoration of hair growth was more significant in HA-iMSC-EVs than in iMSC-EVs, and was comparable to that in mice treated with finasteride. Consistently, the decreased anagen ratio induced by testosterone was reversed by HA-iMSC-EVs, but not by iMSC-EVs. An increased expression of hair follicular β-catenin protein, as well as the reduction of AR was observed in the skin tissue of AGA mice receiving HA-iMSC-EVs, but not in those treated with iMSC-EVs.

CONCLUSIONS

Our results suggest that HA-iMSC-EVs have potential to improve AGA by regulating growth factors/cytokines and stimulating AR-related Wnt/β-catenin signaling.

Efficacy of Adipocyte-Derived Stem Cells-Conditioned Media in Telogen Effluvium

Objectives

To assess the effectiveness of adipocyte-derived mesenchymal stem cells-conditioned media (ADSC-CM) formulation in telogen effluvium patients.

Methods

A retrospective cohort study was conducted at a dermatology clinic in Jeddah, Saudi Arabia. The study included 50 consecutive patients aged 20-70 years, who were diagnosed with telogen effluvium. All patients received five monthly sessions of the same commercial ADSC-CM formulation, using a standardized application protocol. Pre- and post-intervention changes in trichometry parameters were analyzed.

Results

There was a significant increase in mean hair density (up to 29.01 hair/cm2; effect size 0.7-1.0), cumulative hair thickness (up to 2.67 units; effect size 0.7-1.4), and the number of follicular hair units (up to 19.96%; effect size 1.0-1.3) in all scalp regions (p < 0.001), associated with a decrease in mean trichometry-derived Sinclair scale by 0.8-1.3 (p < 0.001). Positive outcomes were observed in 70%-92% of the patients depending on the parameter and scalp region. There was no impact of the patient's age on ADSC-CM efficacy.

Conclusion

ADSC-CM was successfully applied as a new treatment option for patients with telogen effluvium. These findings provide another therapeutic and research area for dermatologists to optimize the management of telogen effluvium and reduce its impact on patients.

Systematic review of exosome treatment in hair restoration: Preliminary evidence, safety, and future directions

BACKGROUND

Exosomes are small extracellular vesicles with potential roles in modulating the hair growth cycle and are an emerging therapy for patients with alopecia. In recent years, researchers have made significant progress in deciphering the network of cellular interactions and signaling pathways mediated by the transfer of exosomes. This has opened the door to a wide range of potential therapeutic applications with an increasing focus on its application in precision medicine.

AIM

To evaluate current published evidence, both preclinical and clinical, on the use of exosomes for hair restoration.

METHODS

In January 2023, a systematic search was conducted using PubMed, Embase, and the Cochrane Library. Records were identified, screened, and assessed for eligibility as per the PRISMA guideline.

RESULTS

We identified 16 studies (15 preclinical and 1 clinical) showing varying degrees of efficacy using exosomes derived from sources including adipose-derived stem cells (ADSCs) and dermal papilla cells (DPCs). Applications of exosomes isolated from ADSCs (ADSC-Exo) and DPCs have shown early promising results in preclinical studies corroborated by results obtained from different model systems. Topical ADSC-Exo has been tried successfully in 39 androgenetic alopecia patients demonstrating significant increases in hair density and thickness. No significant adverse reactions associated with exosome treatment have been reported thus far.

CONCLUSIONS

Although current clinical evidence supporting the use of exosome treatment is limited, there is a growing body of evidence suggesting its therapeutic potential. Further studies are warranted to define its mechanism of action, optimize its delivery and efficacy, and to address important safety concerns.

Reversing Gray Hair: Inspiring the Development of New Therapies Through Research on Hair Pigmentation and Repigmentation Progress

Hair graying is a common and visible sign of aging resulting from decreased or absence of melanogenesis. Although it has been established that gray hair greatly impacts people's mental health and social life, there is no effective countermeasure other than hair dyes. It has long been thought that reversal of gray hair on a large scale is rare. However, a recent study reported that individual gray hair darkening is a common phenomenon, suggesting the possibility of large-scale reversal of gray hair. In this article, we summarize the regulation mechanism of melanogenesis and review existing cases of hair repigmentation caused by several factors, including monoclonal antibodies drugs, tyrosine kinase inhibitors (TKIs), immunomodulators, other drugs, micro-injury, and tumors, and speculate on the mechanisms behind them. This review offers some insights for further research into the modulation of melanogenesis and presents a novel perspective on the development of clinical therapies, with emphasis on topical treatments.

Garlic Exosomes Promote Hair Growth Through the Wnt/β-catenin Pathway and Growth Factors

Background Exosomes are membrane-derived nanovesicles produced by cells and play an important role in intercellular communication. Objectives This study aimed to investigate the effects of garlic exosome (GE) on hair growth. Methods Forty-two Sprague-Dawley/Wistar albino rats were randomly divided into six groups: non-shaved control, shaved control, topical control, GE 2 mg, GE 4 mg, and topical GE. At the end of the experiment, the number of hair follicles, follicle diameter, and subcutaneous tissue thicknesses were measured histopathologically. The Wnt-1, β-catenin, platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), transforming growth factor-β1 (TGF-β1), and collagen I levels were measured by the Western Blot method. Results The anagen follicle counts of the GE 2 mg, 4 mg, and topical GE groups were 66.57±15.49, 105.71±25.06, and 55.29±6.72, and were significantly higher than the control groups (p<0.01, p<0.001 and p<0.05, respectively). The follicle diameter of the GE 4 mg group was higher than the others (p<0.05). The Wnt-1, PDGF, VEGF, TGF-β1, and collagen I levels of all GE groups, and the β-catenin levels of the GE 4 mg and topical GE groups were significantly higher than the control groups (p<0.05). Conclusion GE induces hair growth in rats via the Wnt-1, β-catenin, VEGF, PDGF, and TGF-β1 signaling pathways.

Exosome Therapy in Hair Regeneration: A literature review of the evidence, challenges, and future opportunities

BACKGROUND

Alopecia is a common chief complaint and is challenging to treat. As such, regenerative treatments to promote hair growth are an emerging area of research. Exosomes, which are extracellular vesicles involved in cell communication, homeostasis, differentiation, and organogenesis, have been shown to play a central role in hair morphogenesis and regeneration with potential for use as alopecia treatment.

AIMS

This review summarizes and assesses the body of literature surrounding exosomes as regenerative therapeutics for alopecia and identifies areas for improvement in future research.

METHODS

A review was conducted using a comprehensive list of keywords including "exosome," "alopecia," and "hair loss" on PubMed, EMBASE, and Google Scholar databases published from inception to February 2022. Reference lists of identified articles were included. 47 studies were included. Clinical trial databases were searched using the term "exosome," however no trials relevant to hair growth were identified.

RESULTS

Our updated and comprehensive review details the history of exosome use in medicine, postulated underlying mechanisms in treating hair loss, and current clinical studies. Preclinical studies demonstrate clear benefits of exosome therapeutics in regenerative medicine and for hair loss treatment. Clinical trials demonstrate safety of exosome use in medicine, but data showing efficacy and safety of exosome therapy for alopecia are lacking. We identified several gaps in knowledge required for effective clinical translation including safety, exosome source, and optimal treatment delivery mechanism and dosage.

CONCLUSION

Exosomes are on the horizon as an exciting therapeutic for the treatment of alopecia. Further studies and clinical trials are required.

Isolation of Platelet-Derived Exosomes from Human Platelet-Rich Plasma: Biochemical and Morphological Characterization

Platelet-Rich Plasma (PRP) is enriched in molecular messengers with restorative effects on altered tissue environments. Upon activation, platelets release a plethora of growth factors and cytokines, either in free form or encapsulated in exosomes, which have been proven to promote tissue repair and regeneration. Translational research on the potential of exosomes as a safe nanosystem for therapeutic cargo delivery requires standardizing exosome isolation methods along with their molecular and morphological characterization. With this aim, we isolated and characterized the exosomes released by human PRP platelets. Western blot analysis revealed that CaCl₂-activated platelets (PLT-Exos-Ca²⁺) released more exosomes than non-activated ones (PLT-Exos). Moreover, PLT-Exos-Ca²⁺ exhibited a molecular signature that meets the most up-to-date biochemical criteria for platelet-derived exosomes and possessed morphological features typical of exosomes as assessed by transmission electron microscopy. Array analysis of 105 analytes including growth factors and cytokines showed that PLT-Exos-Ca²⁺ exhibited lower levels of most analytes compared to PLT-Exos, but relatively higher levels of those consistently validated as components of the protein cargo of platelet exosomes. In summary, the present study provides new insights into the molecular composition of human platelet-derived exosomes and validates a method for isolating highly pure platelet exosomes as a basis for future preclinical studies in regenerative medicine and drug delivery.