Mesenchymal Stem Cells Inhibit Proteoglycan Degeneration in a Rat Model of Osteoarthritis

Osteoarthritis (OA) is a degenerative disease, which is characterized pathologically by degeneration of articular cartilage.
One of the mechanisms of cartilage lesion in OA is decreased synthesis of cartilage matrix and amongst the variety of treatment methods
for OA, cell base therapies has a crucial role.
Objectives: The purpose of this study was to understand the regeneration effect of mesenchymal stem cells as well as secretions of these
cells after induction of early-stage Osteoarthritis (OA).
Materials and Methods: To achieve this aim articular cartilages of rat knees were cured by monosodium iodoacetate (1 mg/50 µL).
Mesenchymal Stem Cells (MSCs) were cultured and injected into the knee joint of rats after two weeks. The left knee was kept as the
control group and injected with either sterill saline. The animals were sacrifced at two weeks after transplantation. The knee joints were
harvested and safranin-o and toluidine-blue microscopic analysis were performed. In order to assess changes, the amount of control and
experimental cartilage extracellular matrix structure (proteoglycan) and cartilage fbrillation were determined by using histological
approaches.
Results: The results revealed a decrease of proteoglycan content in the superfcial and intermediate zones and presence of surface
fbrillation. Therefore, OA induced matrix degeneration, and the reparative effects of MSCs were higher than cell secretions.
Conclusions: It can be concluded that due to some bioactive and nutrient factors, MSCs secretions could be used for recovery of OA as well
as prevention of articular cartilage matrix degeneration, using a high dose of cell secretions.