Effects Of High Glucose, Advanced Glycosylation End Products And Drugs On The Expression Of β1-Integrin And FAK

Objectives:To investigate the effects of high glucose and advanced glycation end products (AGEs) on the proliferation, the expression ofβ1-integrin and focal adhesion kinase (FAK), and the secretion of laminin and type IV collagen of cultured human renal mesangial cells (HRMC). To observe the influence of Aminoguanidine, Irbesartan on the proliferation of HRMC, the expression ofβ1-integrin, the secretion of laminin and type IV collagen of cultured HRMC incubated with AGEs.Methods:1. HRMC were incubated with High glucose, AGEs modified bovine serum albumin (AGE-BSA), Aminoguanidine and Irbesartan. 2. The proliferation of HRMC was estimated by MTT. Cell cycle was detected by flow cytometry. 3. The mRNA expression ofβ1-integrin and FAK in HRMC were analyzed by use of RT-PCR. 4. The protein expression ofβ1-integrin and FAK in HRMC were determined by use of Westernblot. 5. The content of typeⅣcollagen and Laminin in cell culture media were measured by radioimmunoassay.Results:1. High glucose and AGE-BSA increased the proliferation rate of HRMC time- and dose- dependently in cultured HRMC, the OD of treated groups show a significantly increase compared to the control group (P<0.05). We also observed the increased S% and the dcreased G1%. Aminoguanidine and Irbesartan can inhibit the proliferation rate of HRMC induced by AGEs, increased G1% and dcreased S%. 2. The levels ofβ1-integrin and FAK mRNA and protein in HRMC were significantly higher than that of normal control. But those in the groups treated with Aminoguanidine and Irbesartan were significantly lower than AGEs groups (P<0.05). 3. The levels of typeⅣcollagen and LN in supernatants of cultured HRMC incubated with high glucose and AGE-BSA higher than those in normal control(P<0.05). Aminoguanidine and Irbesartan can decreased the level of typeⅣcollagen and LN in supernatants of cultured HRMC incubated with AGE-BSA (P<0.05).Conclusions:1. Both high glucose and AGEs promote the proliferation of HRMC, up-regulate the expression ofβ1-integrin and FAK, increase the secretion of ECM in HRMC, which might have potential implications for the pathgenic mechanism of diabetic nephropathy. 2. Aminoguanidine and Irbesartan can play their role of reno-protection via supression of AGEs.