Non-coding RNAs in adipose-derived stem cell exosomes: Mechanisms, therapeutic potential, and challenges in wound healing

Figure 1 Biogenesis and secretion mechanisms of exosomes from adipose-derived stem cells. A: Formation of exosomes; B: Contents of exosomes; C: Mechanisms by which non-coding RNAs serve in wound healing. ER: Endoplasmic reticulum; LSEs: Late-sorting endosomes; ESEs: Early-sorting endosomes; MVBs: Multivesicular bodies; miRNAs: MicroRNAs; cirRNAs: Circular RNAs; lncRNAs: Long non-coding RNAs; HSPs: Heat shock proteins; ECM: Extracellular matrix.

Figure 2 Mechanisms by which microRNAs from adipose-derived stem cell exosomes promote wound healing. miRNAs: MicroRNAs; cirRNAs: Circular RNAs; lncRNAs: Long non-coding RNAs; JAZF1: Juxtaposed with another zinc finger protein 1; PTEN: Phosphatase and tensin homolog deleted on chromosome ten; PIK3R2: Phosphoinositide-3-kinase regulatory subunit 2; DLL-4: Delta-like ligand-4; VEGF: Vascular endothelial growth factor; PI3K: Phosphoinositide-3-kinase; Akt: Protein kinase B; SERPINH1: Serine peptidase inhibitor 1; p-ERK2: Phosphorylated extracellular signal-regulated kinase 2; TMEM127: Transmembrane protein 127; NF-κB: Nuclear factor-kappaB; TGFBR3: Transforming growth factor-beta type III receptor; TGF-β: Transforming growth factor beta; E2F1: Transcription factor 1; TNF-α: Tumor necrosis factor-alpha; IL: Interleukin; α-SMA: Alpha-smooth muscle actin; COL-1: Collagen I; FN: Fibronectin; MMP-9: Matrix metalloproteinase-9.

Figure 3 Mechanisms by which long non-coding RNAs from adipose-derived stem cell exosomes promote wound healing. # represents pretreated with hypoxia. miRNAs: MicroRNAs; cirRNAs: Circular RNAs; lncRNAs: Long non-coding RNAs; EGR-1: Early growth response factor-1; MALAT1: Metastasis-associated lung adenocarcinoma transcript 1; NORAD: Non-coding RNA activated by DNA damage; FOXD2-AS1: FOXD2 antisense RNA 1; DKC1: Dyskeratosis Congenita 1; PAQR3: Progestin and adipoQ receptor family member 3; TLR7: Toll-like receptor 7; VEGF: Vascular endothelial growth factor; PPAR: Peroxisome proliferator-activated receptor; STAT3: Signal transducer and activator of transcription 3; DDR2: Discoidin domain receptor tyrosine kinase 2; FGF2: Fibroblast growth factor 2; ROCK2: Rho-associated coiled-coil containing protein kinase 2; Ulk1: Unc-51 like autophagy activating kinase 1; ROS: Reactive oxygen species; TNF-α: Tumor necrosis factor-alpha; IL: Interleukin.

Figure 4 Mechanisms by which circular RNA from adipose-derived stem cell exosomes promote wound healing. # represents pretreated with hypoxia. miRNAs: MicroRNAs; cirRNAs: Circular RNAs; lncRNAs: Long non-coding RNAs; HK2: Hexokinase 2; FGF4: Fibroblast growth factor 4; SIRT1: Silent information regulator 1; HIF-1α: Hypoxia-inducible factor 1-alpha; NFE2L2: Nuclear factor, erythroid 2 like 2; VEGF: Vascular endothelial growth factor; Nrf1: Nuclear respiratory factor 1; ROS: Reactive oxygen species; TNF-α: Tumor necrosis factor-alpha; IL: Interleukin.