In vitro performance of degenerated disc cells

Abstract

Degeneration of the intervertebral disc (IVD) is a common condition in dogs. Dogs can be divided into two groups with regard to a breed predisposition in the development of IVD degeneration: chondrodystrophic (CD) and Non-chondrodystrophic dogs. To research a potential regenerative therapy with the growth factors TGF-β1 and BMP-2, this study was set up to investigate the effects of these growth factors on the chondrogenic and/or fibrotic differentiation in canine Nucleus Pulposus Cells (NPCs), with regard to expression of various genes, and the differences between NCD and CD breeds regarding these. For this research, cells from the NP of CD and NCD breeds were used. These cells were put in a pellet culture, where 4 different conditions were applied: a control, TGF-β1, in a concentration of 10 ng/mL, BMP-2 in a concentration of 100 ng/mL and of 250 ng/mL. With qPCR, expression levels of various genes involved in, among others, chondrogenesis and fibrosis, and fold changes of these genes were calculated. The results here reported show a better chondrogenic effect on the NP cells than TGF-β1 in cells derived from the NP of CD dog. However, the samples with TGF-β1 also showed a greater fibrotic effect compared to BMP-2. For NCD dogs, bot TGF-β1 and BMP-2 showed comparable increases in increasing expression of chondrogenic genes, however, as addition of BMP-2 possibly is associated with a higher rate of apoptosis, based on a decrease TIMP-1 expression, a slight preference for TGF-β1 could be made.