No abstract

Mesenchymal stem cells (MSCs) have gained wide therapeutic acceptance in regenerative medicine due to their potential in repair process in restoring the damaged tissues and controlling inflammation. In the present study, we report for the first time the beneficial effects of combining placentalderived MSCs (hPMSCs) with stigmasterol-a plant-derived sterol to accelerate cartilage repair and regeneration in a monosodium-iodoacetate (MIA) induced osteoarthritis (OA) rat model. Control animals (Group I) received no treatment. Experimental animals (Group II) received a single intra-articular injection of MIA (2 mg) in the right knee joints. The Group II animals developed OA-like lesions within a week of MIA injection. They were subdivided further as: (II-A): OA, (II-B): OA+hPMSCs (2×10 6 cells, single-dose/ intra-articular injection), (II-C): OA+stigmasterol (20 µg/mL, single-dose/intra-articular injection) and (II-D): OA+hPMSCs+stigmasterol. The animals were monitored for four more weeks after which they were sacrificed, the right limbs dissected out and assessed for cartilage repair and regeneration using microcomputed tomography (micro-CT) and histology. Results showed that the combined administration of hPMSCs with stigmasterol (II-D) was the most effective in correcting the OA lesions, with concomitant repair and regeneration. However, hPMSCs (II-B) or stigmasterol (II-C) per se treated groups showed only marginal beneficial effects and were not significant. Thus the present study provides valuable insights in situ using a combination of hPMSCs and stigmasterol towards cartilage repair and regeneration. We advocate the participation of populating cells or residual chondrocytes in addition to its anti-inflammatory functions.

Obesity (Ob) poses a significant risk factor for the onset of metabolic syndrome with associated complications, wherein the Mesenchymal Stem Cell (MSC) therapy shows pre-clinical success. Here, we explore the therapeutic applications of human Placental MSCs (P-MSCs) to address Ob-associated Insulin Resistance (IR) and its complications. In the present study, we show that intramuscular injection of P-MSCs homed more towards the visceral site, restored HOMA-IR and glucose homeostasis in the WNIN/GR-Ob (Ob-T2D) rats. P-MSC therapy was effective in re-establishing the dysregulated cytokines. We report that the P-MSCs activates PI3K-Akt signaling and regulates the Glut4-dependant glucose uptake and its utilization in WNIN/GR-Ob (Ob-T2D) rats compared to its control. Our data reinstates P-MSC treatment's potent application to alleviate IR and restores peripheral blood glucose clearance evidenced in stromal vascular fraction (SVF) derived from white adipose tissue (WAT) of the WNIN/GR-Ob rats. Gaining insights, we show the activation of the PI3K-Akt pathway by P-MSCs both in vivo and in vitro (palmitate primed 3T3-L1 cells) to restore the insulin sensitivity dysregulated adipocytes. Our findings suggest a potent application of P-MSCs in  pre-clinical/Ob-T2D management.