Isolation, production, and analysis of small leucine-rich proteoglycans in bone

Abstract

Small leucine-rich proteoglycans (SLRPs) are a unique class of proteins that exist in the extracellular matrix, playing key roles in cell proliferation and function. In bone, SLRPs such as bigly can and decorin affect osteogenesis and bone remodeling. Their essential role in this organ system has created the need to isolate these proteins for study. Bone presents unique obstacles to the study of proteins; however, through the use of demineralizing agents, efficient methods of the purification of proteoglycans have been developed. Additionally, methods have been developed that allow for the production and isolation of proteoglycans from conditioned media, which opens the door to a wide array of in vitro and in vivo assays. In stride with the purification and utilization of proteoglycans is the need to insure proteoglycan identity and purity, which is accomplished through enzymatic deglycosylation and blot analysis.

Matrix-bound Cyr61/CCN1 is required to retain the properties of the bone marrow mesenchymal stem cell niche but is depleted with aging

“…3B – C ), which are involved in organizing and reinforcing the microfilament assembly of collagen VI. Depletion of collagen I, in concert with an upregulation in collagen VI and associated proteoglycans and glycoproteins, provides additional evidence that remodeling of the collagenous matrix is one of the major events that occurs in the BM niche with aging [ 63 , 64 ] These alterations in the BM-MSC matrisome likely contribute to the distinct differences in architecture and mechanical properties displayed by young and elderly ECMs ( Fig. 2 ).…”

The Bone Extracellular Matrix in Bone Formation and Regeneration

“…SLRPs are secreted extracellular proteins that interact with cell surface receptors and cytokines to regulate both normal and pathological cellular behaviors. During bone formation, SLRPs participate in all stages including cell proliferation, osteogenesis, mineral deposition, and bone remodeling (Kirby and Young, 2018). In addition, SLRPs regulate the process of collagen fibrillogenesis, the dysregulation of which leads to defects in the organization and production of collagen, culminating in fibrosis due to either orthopedic injuries or genetic deficiencies (Moorehead et al, 2019).…”

Design strategies for composite matrix and multifunctional polymeric scaffolds with enhanced bioactivity for bone tissue engineering

“…SLRPs are extracellular proteins secreted by cells that collaborate with cell-surface receptors and cytokines to regulate both healthy and unhealthy cellular functions. SLRPs are involved in all phases of bone development, such as cellular multiplication, osteogenesis, mineral deposition, and bone remodelling ( Kirby and Young, 2018 ). SLRPs also control the collagen fibrillogenesis process.…”