Final answer:
Proteoglycan aggregates in the connective tissue ECM provide structural support, moisture retention for hydration, compression resistance, shock absorption, viscosity, lubrication, and play roles in cell migration and tissue turgor. They interact with ECM proteins like collagen and aid in the compressibility of cartilage.
Step-by-step explanation:
Proteoglycan aggregates have various effects in the connective tissue extracellular matrix (ECM). They are composed of glycosaminoglycans (GAGs) linked to proteins, forming large structures that occupy significant space within the ECM. These aggregates contribute greatly to the structural support of tissues by interacting with other ECM components like collagen, elastin, fibronectin, and laminin.
Moreover, their substantial polysaccharide branches attract and trap moisture, forming a clear, viscous, and colorless matrix which is known as ground substance. This substance provides essential hydration and consequently helps to resist compression, allowing the ECM to withstand various forces without collapsing. In addition, this characteristic allows proteoglycans to act as biological shock absorbers and play a role in the viscosity and lubrication of joints by contributing to the turgor of tissues.
Furthermore, these properties enable proteoglycans to facilitate cell migration and have a distinct role in the compressibility of structures like cartilage, important in weight-bearing activities. Thus, proteoglycan aggregates are vital in maintaining the integrity and functionality of connective tissues throughout the body.