Recent advances in exosomal non-coding RNA-based therapeutic approaches for photoaging

Abstract

Background: Photoaging is a degenerative biological process that affects the quality of life. It is caused by environmental factors including ultraviolet radiation (UVR), deep skin burns, smoking, active oxygen, chemical substances, and trauma. Among them, UVR plays a vital role in the aging process.

Aim: With the continuous development of modern medicine, clinical researchers have investigated novel approaches to treat aging. In particular, mesenchymal stem cells (MSCs), non-coding RNAs are involved in various physiological processes have broad clinical application as they have the advantages of convenient samples, abundant sources, and avoidable ethical issues.

Methods: This article reviews research progress on five types of stem cell, exosomes, non-coding RNA in the context of photoaging treatment: adipose-derived stem cell, human umbilical cord MSCs, epidermal progenitor cells, keratinocyte stem cells, and hair follicle stem cells (HFSCs). It also includes stem cell related exosomes and their non-coding RNA research.

Results: The results have clinical guiding significance for prevention and control of the onset and development of photoaging. It is found that stem cells secrete cytokines, cell growth factors, non-coding RNA, exosomes and proteins to repair aging skin tissues and achieve skin rejuvenation. In particular, stem cell exosomes and non-coding RNA are found to have significant research potential, as they possess the benefits of their source cells without the disadvantages which include immune rejection and granuloma formation.

Keywords: exosome; mesenchymal stem cells; non-coding RNA; photoaging; skin cancer; ultraviolet radiation.

FIGURE 1

Effect of UV radiation on the skin. Ultraviolet A (UVA) and B (UVB), blue light (400−440 nm), and infrared radiation cause epidermal and dermal cell damage, inducing photoaging and light‐induced skin cancer through oxidative damage, telomere shortening, and DNA damage. UVC is absorbed by the ozone layer. Other factors can also cause photoaging and skin cancer, such as deep skin burns, trauma, smoking, diet, chemical factors, and chronic stress.

FIGURE 2

Photoaging signaling pathways. Three photoaging signal pathways elucidates the molecular mechanisms of photoaging such as the transforming growth factorβ, mitogen‐activated protein kinase, and bone morphogenetic protein (BMP) pathways. Furthermore, micro ribonucleic acids (RNAs) are short noncoding RNAs that is related to regulating biological processes.

FIGURE 3

Applications of stem cells. Stem cells derived from fat, hair, umbilical cord, and epidermis are cultured and expanded in vitro, and injected into photo‐aged skin using three methods: stem cells, culture media, and exosomes. They contain cell growth factors that stimulate fibroblast and collagen proliferation to achieve anti‐aging effects.

FIGURE 4

Mechanisms of regulations by RNAs. Non‐coding RNAs, including microRNAs, long non‐coding RNAs and cyclic RNAs, affect cell growth, proliferation, and metabolism by regulating a variety of mechanisms.