Effects of mesenchymal stromal cells on motor function and collagen in the skeletal muscles of rats with type I diabetes

Bone Marrow Mesenchymal Stem Cells (BMSCs)-Exosomes Carrying MicroRNA-965 Attenuates Allogeneic Renal Transplant Rejection Through Regulation of Janus Kinase/Signal Transducers and Activators of Transcription 3 (JAK/STAT3)

This study intends to evaluate the potential effect of BMSC-derived exosomes (exo) on the rejection of allogeneic kidney transplantation in a rat model. BMSCs were cultured and their exos were collected for characterization, in which the expression of miR-965 was detected by PCR. Rats received orthotopic kidney transplantation and treated with exos or PBS followed by analysis of serum creatinine and BUN, inflammatory cell infiltration, renal fibrosis and vascular wall fibrosis by immunohistochemistry staining, JAK2/STAT3 phosphorylation by Western-blot, the inflammatory factor level by ELISA kit, and CD4+ cells differentiation by flow cytometry. miR-965 was enriched in BMSC-derived exo. Treatment with exo ameliorated the allograft rejection, improved renal function, and reduced the histological changes of kidney. In addition, exosomal treatment decreased the level of serum inflammatory cytokines, and altered T cell subpopulations. Meanwhile, fibrosis and neointima formation was reduced as demonstrated by related protein expression and signaling pathways was inactivated in the presence of exos. In conclusion, the miR-965 derived from BMSC-exos mitigated the renal allograft rejection through JAK/STAT3 signaling.

Use of human bone marrow mesenchymal stem cells immortalized by the expression of telomerase in wound healing in diabetic rats

Diabetes mellitus is associated with neural and micro- and macrovascular complications. Therapeutic options for these complications are limited and the delivery of mesenchymal stem cells into lesions have been reported to improve the healing process. In this work, the effects of the administration of a lineage of human bone marrow mesenchymal stem cells immortalized by the expression of telomerase (hBMSC-TERT) as a potential therapeutic tool for wound healing in diabetic rats were investigated. This is the first description of the use of these cells in diabetic wounds. Dorsal cutaneous lesions were made in streptozotocin-induced diabetic rats and hBMSC-TERT were subcutaneously administered around the lesions. The healing process was evaluated macroscopically, histologically, and by birefringence analysis. Diabetic wounded rats infused with hBMSC-TERT (DM-TERT group) and the non-diabetic wounded rats not infused with hBMSC-TERT (CW group) had very similar patterns of fibroblastic response and collagen proliferation indicating improvement of wound healing. The result obtained by birefringence analysis was in accordance with that obtained by the histological analysis. The results indicated that local administration of hBMSC-TERT in diabetic wounds improved the wound healing process and may become a therapeutic option for wounds in individuals with diabetes.

Effects of mesenchymal stromal cells on motor function and collagen in the skeletal muscles of rats with type I diabetes

The present study aimed to evaluate the effects of mesenchymal stromal cell (MSC) transplantation on motor function and collagen organization in the muscles of rats with type 1 diabetes mellitus. Male Wistar rats were randomly assigned to three groups: control (C), diabetic (DM) and diabetic treated with MSCs (DM-MSCs). Diabetes was induced by streptozotocin (50 µg/kg). Bone marrow cells were isolated from the tibia and femur. After 10 weeks of DM induction, the DM-MSC rats received four i.p. injections of MSCs (1 × 106). Ten weeks after MSC transplantation, motor performance was evaluated by the rotarod test and the anterior tibial (TA) muscles were collected for morphometric and quantification of collagen birefringence by polarizing microscopy analysis. Motor performance of the DM group was significantly reduced when compared to the C group and increased significantly in the DM + MSC group. The TA muscle mass was significantly reduced in the DM and DM + MSC groups compared to the C group. The connective tissue increased in the DM group compared to the C group and decreased in the DM + MSC group. The percentage collagen birefringence decreased significantly in the DM group when compared to the C group and increased in the DM + MSC group. Motor performance was positively correlated with collagen birefringence and negatively correlated with percentage of connective tissue. The results indicate that MSC transplantation improves both motor function and the collagen macromolecular organization in type 1 DM.