Adipose mesenchymal stem cells–derived exosomes attenuate retina degeneration of streptozotocin-induced diabetes in rabbits

Figure 1.. Ultrastructure of exosomes. Exosomes isolated from MSCs. They are heterogeneous in size, ranging from 30 nm to 100 nm. They are directly frozen and observed by cryo-electron microscopy without chemical fixation or contrasting. Exosomes appear round and are visualized with improved resolution (arrows). Scale bar 100 nm. MSCs: mesenchymal stem cells.

Figure 2.. (a) Western blot scanning densitometry of CD81 versus β-actin protein levels in MSCs-derived exosomes in different passages. Lane 1: passage 1, Lane 2: passage 2, Lane 3: passage 3. (b) Mean of ratio of CD81 versus β-actin protein levels in MSCs-derived exosomes in different passages. CD81 showed a significant increased level in passage 2 when compared to passage 1 and significant elevated levels in passage 3 when compared to passage 2. P1: passage 1; P2: passage 2, and P3: passage 3. MSCs: mesenchymal stem cells.

Figure 3.. MSCs-derived exosomes labeled with PKH26 under fluorescent microscopy. MSCs: mesenchymal stem cells.

Figure 4.. (a) Photomicrograph of retina tissue of positive control (diabetic eye) showing abnormal thickness of all retina layers (GL, IPL, OPL, ONL) with well-observed degenerative areas in both GL and IPL, H&E ×100. (b) Photomicrograph of retina tissue of positive control (diabetic eye) showing hemorrhage in IPL and ONL, H&E ×100. (c) Photomicrograph of retina tissue of positive control (diabetic eye) showing complete damage of GL and IPL layer with well-observed hemorrhage and abnormal thickness of all other retinal layers, H&E ×100. GL: ganglionic layer; IPL: inner plexiform layer; OPL: outer plexiform layer; ONL: outer nuclear layer; OLL: outer limited layer rod and cone; H&E: hematoxylin and eosin.

Figure 5.. (a) Photomicrograph of retina tissue of SC MVs–injected groups showing well-organized retinal layers with well-observed vacuolation in ONL, GL, and IPL, H&E ×100. (b) Photomicrograph of retina tissue of SC MVs–injected groups at the end of experimental duration with retinal tissue showing normal architecture, H&E ×100. GL: ganglionic layer; IPL: inner plexiform layer; ONL: outer nuclear layer; OLL: outer limited layer rod and cone; INL: inner nuclear layer; H&E: hematoxylin and eosin; SC: subconjunctival; MVs: microvesicles.

Figure 6.. (a) Photomicrograph of retinal tissue after IO MVs injection showing degeneration and vacuoles in GL and IPL, H&E ×100. (b) Photomicrograph of retinal tissue after IO MVs injection showing well-defined components of retinal layer, H&E ×100. GL: ganglionic layer; IPL: inner plexiform layer; H&E: hematoxylin and eosin; MVs: microvesicles; IO: intraocular.

Figure 7.. Photomicrograph of retinal tissue after IV MVs injection showing well-defined layers with increase in all layer thickness (IPL, INL, ONL, and OLL) and losing their regular form, H&E ×100. IPL: inner plexiform layer; INL: inner nuclear layer; ONL: outer nuclear layer; OLL: outer limited layer rod and cone; H&E: hematoxylin and eosin; MVs: microvesicles; IV: intravenous.

Figure 8.. Relative quantitation of micRNA-222 expression levels in all studied groups. micRNA-222 showed marked decrease in diabetic group with retinal degenerative changes in comparison to other groups involved in the study.

Figure 9.. Correlation of plasma micRNA-222 expression level with serum glucose in all studied groups.

Figure 10.. Correlation of serum micRNA-222 expression level with serum insulin in all studied groups.