High glucose reduces generation of plasmin activity by mesangial cells

Area of Science:

• Nephrology
• Cell Biology
• Biochemistry

Background:

• Mesangial enlargement is a hallmark of diabetic nephropathy.
• Reduced mesangium degradation occurs in high glucose environments.
• Plasmin is crucial for extracellular matrix degradation.

Purpose of the Study:

• To investigate the effect of high glucose on the plasminogen cascade in mesangial cells.
• To determine if high glucose impairs mesangial cell plasmin generation.

Main Methods:

• Cultured human mesangial cells were exposed to high glucose concentrations.
• Analysis of plasminogen cascade components (plasminogen, urokinase-type plasminogen activator, tissue-type plasminogen activator, plasminogen activator inhibitor-1) on cell surface and associated with cells.
• Measurement of mesangial cell plasmin activity generation.

Main Results:

• High glucose decreased plasminogen and urokinase-type plasminogen activator binding to mesangial cells.
• High glucose increased tissue-type plasminogen activator and plasminogen activator inhibitor-1 associated with mesangial cells.
• Overall reduction in mesangial cell plasmin activity generation under high glucose conditions.

Conclusions:

• High glucose significantly alters the plasminogen cascade on mesangial cells.
• This alteration leads to reduced plasmin generation capacity in a high glucose milieu.
• The impaired plasmin activity may explain reduced mesangium degradation in diabetic nephropathy.