Fig. 1.

MG induces barrier dysfunction in human brain microvascular endothelial cells (IHECs) under various glucose conditions. (A) Time course of MG-induced transendothelial electrical resistance (TEER) in IHECs adapted to 5 mM glucose (normoglycemia) or to 25 mM glucose (hyperglycemia, 12 days) or to 25 mM glucose followed by transfer to 5 mM glucose (acute glycemic fluctuation, 25→5 mM). MG concentration was 1 mM. TEER in confluent IHEC monolayers on inserts was recorded for 6 h with a voltohmeter. Only inserts with a minimum baseline monolayer resistance of 200 Ω/0.33 cm² were used in the experiments. TEER was expressed as percent of the baseline to account for batch-to-batch variation. ^⁎p<0.05 vs control, n=3. (B) Hyperglycemia and acute glycemic fluctuation exacerbates MG-induced TEER loss. TEER was determined in IHEC monolayers grown in different glucose conditions: 5, 25 mM or 25→5 mM and treated with 0–300 µM MG. ^⁎p<0.05 vs 5 mM glucose, n=3.