CML/RAGE signal induces calcification cascade in diabetes

Area of Science:

• Vascular Biology and Pathology
• Diabetic Complications
• Biochemistry

Background:

• Vascular calcification is a critical predictor of cardiovascular events and amputations.
• Advanced glycation end-products (AGEs) contribute to vascular calcification, but the role of Nε-carboxymethyl-lysine (CML) in diabetic atherosclerosis is unclear.

Purpose of the Study:

• To investigate the role and mechanism of CML in diabetic atherosclerotic calcification.
• To elucidate the CML-mediated signaling pathway in diabetic vascular disease.

Main Methods:

• In vivo study of 45 diabetic patients undergoing amputation, assessing arterial calcification and serum CML levels.
• In vitro study using A7r5 aortic smooth muscle cells to investigate the CML/RAGE signaling pathway.
• Utilized ELISA, ultrasound, H&E, von Kossa staining, calcium assays, and Western blotting.

Main Results:

• Serum CML levels positively correlated with arterial calcification in diabetic patients.
• CML/RAGE signaling intensity increased with atherosclerotic calcification progression.
• In vitro studies identified the CML/RAGE-ROS-p38MAPK-cbfα1-ALP pathway as crucial for CML-induced calcification.

Conclusions:

• Spotty calcification is characteristic of atherosclerotic plaques in diabetic patients with amputation.
• The CML/RAGE pathway, involving reactive oxygen species (ROS) and p38MAPK, significantly contributes to the diabetic calcification cascade.