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Activation of the type 1 angiotensin II receptor ([AT.sub.1]) triggers proinflammatory signaling through pathways independent of classical Gq signaling that regulate vascular homeostasis. Here, we report that the [AT.sub.1] receptor preformed a heteromeric complex with the receptor for advanced glycation endproducts (RAGE). Activation of the [AT.sub.1] receptor by angiotensin II (Ang II) triggered transactivation of the cytosolic tail of RAGE and NF-[kappa]B-driven proinflammatory gene expression independently of the liberation of RAGE ligands or the ligand-binding ectodomain of RAGE. The importance of this transactivation pathway was demonstrated by our finding that adverse proinflammatory signaling events induced by [AT.sub.1] receptor activation were attenuated when RAGE was deleted or transactivation of its cytosolic tail was inhibited. At the same time, classical homeostatic Gq signaling pathways were unaffected by RAGE deletion or inhibition. These data position RAGE transactivation by the [AT.sub.1] receptor as a target for vasculoprotective interventions. As proof of concept, we showed that treatment with the mutant RAGE peptide S391A-[RAGE.sub.362-404] was able to inhibit transactivation of RAGE and attenuate Ang II-dependent inflammation and atherogenesis. Furthermore, treatment with WT [RAGE.sub.362-404] restored Ang II-dependent atherogenesis in Ager/Apoe-KO mice, without restoring ligand-mediated signaling via RAGE, suggesting that the major effector of RAGE activation was its transactivation., IntroductionBlockade of the renin-angiotensin aldosterone system (RAAS) is one of the most prescribed treatments in all of medicine. The pleiotropic benefits of RAAS blockade on inflammation (1-3), atherogenesis (4, 5), [...]

Glucagon-like peptide 1 receptor agonists improve glucose control, promote weight loss and reduce the risk of major cardiovascular events in people with type 2 diabetes mellitus. The FLOW study now provides unequivocal evidence of kidney protective effects with semaglutide in adults with type 2 diabetes mellitus and chronic kidney disease. [ABSTRACT FROM AUTHOR]

Diabetic nephropathy is a leading cause of end-stage renal disease. Statins may exert renoprotective effects independently of lipid-lowering properties. We investigated the pleiotropic effects of rosuvastatin on renal structure and function in streptozotocin diabetic apolipoprotein-E knockout (Apo-[E.sup.-/-]) mice, a model of progressive nephropathy in which dyslipidemia is resistant to statin treatment. These effects were compared with those observed with conventional renin-angiotensin system blockade (candesartan) or combined treatment. Nondiabetic and diabetic Apo-[E.sup.-/-] mice were randomized to no treatment or treatment with candesartan (2.5 mg/kg), rosuvastatin (5 mg/kg), or their combination per gavage for 20 wk. Urine and blood samples were collected for assessment of albuminuria, creatinine clearance, plasma lipids, glucose, and glycated hemoglobin. Renal sclerosis was analyzed on paraffin-embedded kidney sections stained with periodic acid-Schiff. Renal expression of collagen IV, fibronectin and advanced glycation end products (AGEs), receptor for advanced glycation and products (RAGE), NADPH oxidase 4 (NOX4), and nitrotyrosine was assessed by real-time PCR and/or immunohistochemistry. Diabetes-induced albuminuria was not affected by rosuvastatin and combination treatment but was prevented by candesartan. Diabetes resulted in increased creatinine clearance, which was not modified by the treatments. Rosuvastatin and/or candesartan prevented diabetes-associated renal extracellular matrix accumulation. Rosuvastatin reduced accumulation of AGEs and expression of RAGE, NOX4, and nitrotyrosine. In conclusion, in the diabetic Apo-[E.sup.-/-] mouse, rosuvastatin confers renal benefits that are independent of lipid lowering and equivalent or greater to those observed with candesartan. The combination treatment is not superior to monotherapies. experimental diabetes; kidney disease; angiotensin type 1 receptor antagonist; statin doi: 10.1152/ajprenal.00127.2010.

The extent to which a reduced nephron endowment contributes to hypertension and renal disease is confounded in models created by intrauterine insults that also demonstrate other phenotypes. Furthermore, recent data suggest that a reduced nephron endowment provides the 'first hit' and simply increases the susceptibility to injurious stimuli. Thus we examined nephron number, glomerular volume, conscious mean arterial pressure (MAP), and renal function in a genetic model of reduced nephron endowment before and after a high-salt (5%) diet. One-yr-old glial cell line-derived neurotrophic factor wild-type (WT) mice, heterozygous (HET) mice born with two kidneys (HET2K), and HET mice born with one kidney (HET1K) were used. Nephron number was 25% lower in HET2K and 65% lower in HET1K than WT mice. Glomeruli hypertrophied in both HET groups by 33%, resulting in total glomerular volumes that were similar between HET2K and WT mice but remained 50% lower in HET1K mice. On a normal-salt diet, 24-h MAP was not different between WT, HET2K, and HET1K mice (102 [+ or -] 1, 103 [+ or -] 1, and 102 [+ or -] 2 mmHg). On a high-salt diet, MAP increased 9.1 [+ or -] 1.9 mmHg in HET1K mice (P < 0.05) and 5.4 [+ or -] 0.9 mmHg in HET2K mice (P < 0.05) and did not change significantly in WT mice. Creatinine clearance was 60% higher in WT mice but 30% lower in HET2K and HET1K mice fed a high-salt diet than in controls maintained on a normal-salt diet. Thus a reduction in nephron number (or total glomerular volume) alone does not lead to hypertension or kidney disease in aged mice, but exposure to high salt uncovers a hypertensive and renal phenotype. nephron number; congenital nephron deficit; hypertension; unilateral renal agenesis; salt sensitivity doi: 10.1152/aj prenal.00049.2010.

Advanced glycation end products (AGEs) and the receptor for AGEs (RAGE) generate ROS, and therefore this study evaluated the effects of RAGE deletion, decreasing AGE accumulation, or lowering dietary AGE content on oxidative parameters in diabetic nephropathy (DN). Control and diabetic male wild-type and RAGE-deficient ([RAGE.sup.-/-]) mice were fed high- or low-AGE diets, with two groups given the inhibitor of AGE accumulation, alagebrium chloride, and followed for 24 wk. Diabetic [RAGE.sup.-/-] mice were protected against albuminuria, hyperfiltration, glomerulosclerosis, decreased renal mitochondrial ATP production, and excess generation of both mitochondrial and cytosolic superoxide. Whereas glomerulosclerosis, tubulointerstitial expansion, and hyperfiltration were improved in diabetic mice treated with alagebrium, there was no effect on urinary albumin excretion. Both diabetic [RAGE.sup.-/-] and alagebrium-treated mice had an attenuation of renal RAGE expression and decreased renal and urinary AGE (carboxymethyllysine) levels. Low-AGE diets did not confer renoprotection, lower the AGE burden or renal RAGE expression, or improve cytosolic or mitochondrial superoxide generation. Renal uncoupling protein-2 gene expression and mitochondrial membrane potential were attenuated by all therapeutic interventions in diabetic mice. In the present study, diverse approaches to block the AGE-RAGE axis had disparate effects on DN, which has potential clinical implications for the way this axis should be targeted in humans. advanced glycation; advanced glycation end products; receptor of advanced glycation end products doi:10.1152/ajprenal.00591.2009