Background: Diabetic retinopathy (DR) is one of the most common microvascular complication of diabetes that affects the
retina and causes acquired blindness among working-age people. Stem cell therapy and exosomes have become promising
therapeutic strategies for DR with the development of modern medical technology in the field of cell therapy.
Objective: To evaluate the possible potential therapeutic effect of bone marrow derived Mesenchymal stem cells (BMMSCs)
and their exosomes (BMMSCs-exosomes) on induced diabetic retinopathy in rats.
Materials and Methods: Ten young rats were used to prepare mesenchymal stem cells (MSCs). Sixty-four adult male albino
rats were divided into six groups. Group I (Control group). Group II (affected group): Rats received single intraperitoneal
injection of STZ (60 mg/kg body weight), freshly dissolved in citrate buffer. Group III: DR treated with BMMSCs. Group
IV: DR treated with BMMSCs-exosomes. Group V: DR treated with BMMSCs and MSCs-exosomes. Group VI (recovery
group). Retinal specimens were taken and processed for histological and immunohistochemical examination.
Results: Group II and VI displayed decreased retinal thickness, obvious disorganization of the outer segment of photoreceptors,
together with cytoplasmic vacuolations in the cells of the inner nuclear and ganglionic layers. Furthermore, there was a
significant increase (P < 0.05) in VEGF and vimentin immunoexpression. Groups III and IV showed improvement of some
histological microscopic changes described in group II. While, group V displayed histological architecture and ultrastructure
near to control group.
Conclusion: MSCs and exosomes can treat diabetic retinopathy. However, better results can be obtained when exosomes
were given with MSCs.