From the Guidelines
The extracellular matrix secreted in the kidneys plays a crucial role in maintaining kidney structure and function, and its dysregulation can lead to various kidney diseases. The provided evidence primarily focuses on extracellular vesicles (EVs) rather than the extracellular matrix (ECM). However, based on general knowledge of kidney physiology, the ECM serves multiple critical functions essential for normal kidney structure and function. It provides physical support and structural integrity to kidney tissues, creating a scaffold that maintains the three-dimensional architecture of nephrons, glomeruli, and tubules. The ECM regulates cell behavior by influencing cell adhesion, migration, proliferation, and differentiation through interactions with cell surface receptors, as discussed in the context of EVs and their role in kidney function 1.
Although the studies provided do not directly address the function of the extracellular matrix, they highlight the importance of understanding the components and functions of extracellular substances in the kidneys, such as EVs, which can provide insights into kidney diseases and their potential use as biomarkers and therapeutic agents 1. The ECM acts as a selective filtration barrier in the glomerular basement membrane, allowing small molecules like water and waste products to pass while retaining larger proteins in the bloodstream. Additionally, the ECM stores and regulates growth factors and cytokines, releasing them when needed to coordinate cellular responses. In kidney development, the ECM guides organ formation and cellular organization. During injury, the ECM composition changes to support repair processes, though excessive ECM production can lead to fibrosis and scarring.
Key components of the kidney ECM include collagens, laminins, fibronectin, and proteoglycans, each contributing to these essential functions that maintain kidney homeostasis and proper filtration capabilities. Understanding the role of the ECM in the kidneys is crucial for managing and treating kidney diseases, which can significantly impact morbidity, mortality, and quality of life. Therefore, maintaining the integrity and function of the ECM is vital for preventing kidney disease progression and improving patient outcomes.
From the Research
Function of Extracellular Matrix in the Kidneys
The extracellular matrix (ECM) secreted in the kidneys plays a crucial role in maintaining tissue and organ integrity. Some of the key functions of ECM in the kidneys include:
- Providing a scaffold for surrounding cells and maintaining organ stability 2
- Regulating cell adhesion, proliferation, migration, and differentiation 3, 4
- Influencing cellular phenotypes through its composition, architecture, and stiffness/elasticity 5
- Orchestrating cell signaling, functions, properties, and morphology 4
Composition of Extracellular Matrix in the Kidneys
The ECM in the kidneys is a complex network of proteins, including:
- Collagens, elastin, and glycoproteins such as laminins and tenascins 2, 4
- Proteoglycans and glycosaminoglycans, such as hyaluronan 4
- Enzymes like matrix metalloproteinases and specific glycosidases, including heparanase and hyaluronidases 4
Role of Extracellular Matrix in Kidney Disease
The ECM plays a significant role in the development and progression of kidney diseases, including:
- Kidney fibrosis, where the ECM is pathologically deposited, leading to chronic kidney disease (CKD) 2, 3
- Diabetic kidney disease, where the ECM regulates antifibrotic microRNAs crosstalk and DPP-4 associated-fibrogenic processes 6
- Renal fibrosis, where the ECM can serve as a specific non-invasive biomarker and scaffold in regenerative medicine 2