Application of exosome in various systemic diseases
Introduction
Extracellular vesicles (EVs) are a heterogeneous group of membrane-bound vesicles that are released by cells into the extracellular space. EVs carry a range of bioactive molecules such as proteins, lipids, and nucleic acids, which can be transferred to recipient cells and modulate their behavior. Recently, there has been growing interest in the therapeutic potential of EVs for the treatment of various diseases. One subset of EVs, called exosomes, has been particularly well-studied for their ability to deliver cargo to target cells and tissues. In this review, we will discuss the current state of knowledge on exosome-based therapies for a range of clinical conditions affecting different systems of the body.
Exosome-based therapies for cancer
Exosomes have been shown to play a role in the progression of various cancers, including breast cancer, lung cancer, and melanoma [1-3]. However, exosomes can also be harnessed for therapeutic purposes. Several studies have demonstrated the potential of exosomes as delivery vehicles for nucleic acid-based therapies, such as small interfering RNAs (siRNAs) and microRNAs (miRNAs). For example, Yang et al. engineered exosomes to deliver siRNA targeting the oncogene KRAS to lung cancer cells, resulting in decreased tumor growth in vivo [4]. Another study showed that exosomes loaded with miRNA-34a could inhibit the growth and migration of prostate cancer cells in vitro and in vivo [5]. These findings suggest that exosomes could serve as a promising platform for the development of RNA-based therapies for cancer.
Exosome-based therapies for cardiovascular disease
Cardiovascular disease (CVD) is a leading cause of morbidity and mortality worldwide. Exosomes derived from mesenchymal stem cells (MSCs) have been shown to have beneficial effects on CVD due to their ability to promote angiogenesis, inhibit inflammation, and enhance tissue repair [6]. Preclinical studies have demonstrated that MSC-derived exosomes can improve cardiac function and reduce infarct size in animal models of myocardial infarction [7,8]. In addition, there is emerging evidence to suggest that exosomes derived from endothelial cells, immune cells, and other cell types may also have therapeutic potential for CVD [9-11].
Exosome-based therapies for neurodegenerative disease
Neurodegenerative diseases, such as Alzheimer's disease (AD) and Parkinson's disease (PD), are characterized by the progressive loss of neurons and synapses in the brain. Exosomes have been proposed as a novel therapeutic approach for these conditions due to their ability to transfer molecules across the blood-brain barrier and modulate neuronal function. For example, Wang et al. demonstrated that exosomes isolated from AD patients contained elevated levels of beta-amyloid (Aβ) peptides, which are key pathological hallmarks of the disease [12]. Conversely, exosomes derived from healthy individuals were found to suppress Aβ accumulation in AD mouse models, indicating a potential therapeutic role for exosomes in AD. Similarly, exosomes derived from stem cells have been shown to improve cognitive function in animal models of PD [13]. However, challenges remain in translating these findings to clinical applications due to the complexity of the blood-brain barrier and the need for more robust preclinical studies.
Exosome-based therapies for regenerative medicine
Exosomes derived from stem cells have emerged as a promising tool for regenerative medicine due to their ability to promote tissue repair and regeneration. MSC-derived exosomes have been shown to enhance wound healing, improve bone regeneration, and facilitate cartilage repair [14-16]. In addition to MSCs, exosomes derived from adipose-derived stem cells (ADSCs) and other cell types have also shown potential for regenerative medicine applications [17,18]. However, further research is needed to optimize the production and purification of exosomes for clinical use.
Exosome-based therapies for infectious diseases
Exosomes have been shown to play a role in host-pathogen interactions, with both viral and bacterial pathogens modulating the release and content of exosomes in infected cells [19,20]. However, exosomes can also be harnessed for therapeutic purposes in the context of infectious diseases. For example, exosomes derived from dendritic cells have been shown to stimulate immune responses against viral infections such as hepatitis B and C [21,22]. In addition, exosomes loaded with antimicrobial peptides or siRNAs targeting viral or bacterial genes have been shown to have antiviral and antibacterial effects in vitro and in vivo [23,24]. These findings suggest that exosome-based therapies could be a promising approach for treating infectious diseases.
Conclusion
Exosome-based therapies have the potential to revolutionize the treatment of various clinical conditions affecting different systems of the body. However, the field is still in its early stages and several challenges remain, including the need for standardized protocols for exosome isolation and characterization, optimization of cargo loading and delivery, and rigorous preclinical and clinical testing. Nevertheless, with continued research and development, exosome-based therapies could become a powerful tool in the fight against disease.
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