molecules are transferred to hair follicle cells, stimulating hair growth by promoting cell proliferation, differentiation, and survival.
Moreover, growth factors such as IGF-1, KGF, and VEGF can enhance hair growth by improving blood flow to hair follicles and supplying essential nutrients and oxygen.4 These factors can also stimulate the production of extracellular matrix components, offering structural support to hair follicles and maintaining their integrity.
In conclusion, exosome therapy holds significant potential for hair loss treatment, offering a novel and innovative solution to a prevalent and distressing condition. The advancement of exosome therapy hinges on further research to elucidate its mechanisms of action, long-term effects, and the development of a standardized approach for reporting study results.
Quality of Studies on Exosome Therapy for Hair Loss
While numerous studies have explored the potential benefits of exosome therapy for hair loss in mice, and a few in vitro studies on human hair dermal papilla cells and hair follicles have been conducted, there are currently minimal published human studies.1-3 One study utilizing exosomes in human subjects has recently commenced in Isfahan, Iran; however, the current evidence supporting the use of exosome therapy for hair loss remains limited.7 Given the lack of human studies, it is crucial to exercise caution in interpreting results from animal studies and in vitro studies, as they may not always be directly translatable to humans. Additionally, the methodologies used in these studies vary greatly, making it challenging to compare results and draw conclusions regarding the overall efficacy of exosome therapy for hair loss.
It is essential to address the claims made by some practitioners about the long-lasting effects of a single or limited treatment with exosome therapy. To date, these claims have not been substantiated by research. Long-term studies are necessary to determine the maintenance of treatment effects, and the scientific community should emphasize the importance of such research.
This underscores the importance of standardizing research methodologies and conducting well-designed clinical trials to establish the safety and efficacy of exosome therapy for hair loss in humans. Until more robust evidence is available, it is likely premature to recommend exosome therapy for hair loss to patients. Further research is necessary to determine the optimal dosing, duration of treatment, and safety profile of exosome therapy for hair loss.
Standardization of Exosome Therapy Production and Reporting
Standardization is critical for ensuring the safe and effective use of exosome therapy. The process of obtaining exosomes can vary significantly depending on the source. Autologous exosomes, taken from and given to the same patient, may not require the same level of processing as allogenic exosomes, which are pre-made and ready to use. Pre-made exosome kits, marketed as exosome therapy, can raise concerns due to their often lacking transparency regarding the source and contents of the exosomes. The limited disclosure of the exact contents and potential side effects of these exosomes could pose a significant risk to patients and may lead to life-threatening responses.2 For these reasons, the use of exosome therapy products outside of federally registered clinical trials is currently illegal in the United States. It is essential for clinicians to understand the contents and effects of exosomes before administering them to patients.
Efforts have been made to standardize exosome therapy production and administration. In 2014, the International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles ("MISEV") guidelines, which were further updated in 2018. These contained recommendations on the most appropriate methods of extracellular vesicle isolation, characterization, and reporting. The National Institute of Standards and Technology (NIST) developed reference materials to be used for extracellular vesicle development and reporting. We propose standardized reporting guidelines to be used for exosome therapy research (Table 1) that can help accelerate the translation of exosome-based therapies from laboratories to the clinic.8,9
Exosome Signaling Molecules for Hair Loss
Despite FDA regulations on the use of exosomes in human subjects, research into their use for hair loss continues. In hair loss research, exosomes often contain signaling molecules involved in promoting hair growth, such as beta-catenin, Norrin, Fzd4, Shh, IGF-1, KGF, HGF, Wnt, BMP, miR-22-5p, miR-218-5p, and others (Table 2).10 Autologously derived exosomes are frequently injected into the scalps of laboratory rodents, where they can deliver growth factors and other therapeutic molecules to hair follicles, demonstrating promising results in stimulating new hair growth.
Importance of Creating a Uniform Reporting Method for Exosome Therapy
As research on the potential use of exosome therapy expands, it is crucial to establish a uniform reporting method for research in this area. A standardized approach to reporting research results and patient outcomes will provide a more comprehensive and accurate understanding of the benefits and limitations of exosome therapy, as well as facilitate the development of evidence-based guidelines for treating hair loss with exosome therapy. A uniform reporting method will also promote transparency and consistency in the field, enabling accurate comparison of results across different studies. This will help identify and address any disparities in research quality
