Beyond the glomerular filtration barrier: How endothelial glycocalyx damage drives kidney disease in diabetes.

Current therapies for diabetic kidney disease (DKD) slow progression but fail to halt irreversible renal fibrosis, largely because early pathogenic drivers are overlooked. While endothelial glycocalyx disruption is recognized as an initiator of albuminuria, existing literature lacks a unified model connecting this initial barrier loss to the full fibrotic cascade. This review systematically integrates the molecular networks driving glycocalyx degradation, specifically detailing the synergistic interplay among oxidative stress, sheddase activation, and the AGEs/RAGE/NF-κB axis. Unlike previous reviews, we explicitly map how the shedding of core components-such as Syndecans and Glypicans-triggers downstream leukocyte adhesion via the intracellular MyD88/NF-κB pathway, actively propagating renal inflammation and exacerbating the progression of renal fibrosis. By redefining glycocalyx damage as a critical pathological amplifier that actively drives glomerular filtration barrier disruption and subsequent inflammatory and fibrotic cascades, rather than a passive structural consequence of hyperglycemia, we expose critical gaps in standard DKD management. We further critically evaluate the clinical viability of emerging glycocalyx-targeted strategies, highlighting specific applications for early diagnostic biomarkers and addressing current challenges in targeted drug delivery, ultimately providing a precise roadmap for preventing DKD progression.