Mesangiale

Mesangiale refers to the mesangium, a central, supportive region of the renal glomerulus. The intraglomerular mesangium consists of mesangial cells embedded in a matrix, positioned between the capillary loops. A smaller extraglomerular component, often called the lacis area near the vascular pole, is related to the same cellular lineage.

Mesangial cells are specialized, pericyte-like cells that provide structural support to glomerular capillaries and help regulate filtration surface area through contraction. They participate in immune defense by phagocytosing debris and can present antigens in some contexts. The mesangial matrix, produced by these cells, contains proteins such as collagen and proteoglycans and can remodel in response to injury or disease. Mesangial cells also secrete cytokines and growth factors that influence glomerular remodeling and inflammation.

Clinical relevance arises when the mesangium undergoes expansion or proliferation, a common feature in various glomerular diseases. Mesangial expansion or hypercellularity can accompany IgA nephropathy, diabetic nephropathy, membranoproliferative glomerulonephritis, and other forms of glomerulonephritis. Excessive matrix production can reduce the filtration surface area and alter glomerular mechanics, contributing to progressive kidney dysfunction. The term mesangiopathy may be used to describe disease processes primarily affecting the mesangium.

Diagnosis typically relies on kidney biopsy examined by light microscopy, immunofluorescence, and electron microscopy to assess mesangial hypercellularity, matrix expansion, and immune deposits. Treatment is directed at the underlying renal disease and may include measures to control blood pressure, reduce proteinuria, and manage hyperglycemia in diabetes, with the goal of limiting mesangial injury and remodeling.