However, macrophage infiltration was not normalized by Ac-SDKP treatment

However, macrophage infiltration was not normalized by Ac-SDKP treatment. Open in a separate window Fig 3 Effect of Ac-SDKP on macrophage infiltration. (BP), left ventricular hypertrophy (LVH), albuminuria, decreased glomerular filtration rate (GFR) and increased macrophage infiltration (inflammation) and renal collagen content (fibrosis). Ac-SDKP did not affect BP or LVH in either group; however, it significantly reduced albuminuria, renal inflammation and fibrosis and improved GFR in both prevention and reversal groups. Moreover, slit diaphragm nephrin protein expression in the glomerular filtration barrier was significantly decreased in hypertensive rats. This effect was partially prevented or reversed by Ac-SDKP. We concluded that Ac-SDKP greatly attenuates albuminuria and renal fibrosis and enhances renal function in rats with 5/6Nx. These effects may be related to decreased swelling (macrophages) and improved Rabbit Polyclonal to TAS2R13 nephrin protein. Ac-SDKP inhibits fibroblast and mesangial cell proliferation and collagen synthesis6-8. Treatment with Ac-SDKP offers been shown to reduce swelling and collagen deposition in the heart, aorta and kidney in animal models of hypertension, myocardial infarction and diabetes 3,9-13. The glomerular filtration barrier is definitely a three-layered structure consisting of a) fenestrated endothelial cells lining the renal capillaries, b) the glomerular basement membrane (GBM), and c) visceral epithelial cells (podocytes) whose interdigitating foot processes form the slit diaphragm.14 The slit diaphragm is the final barrier that helps prevent protein leakage into the urinary space. Nephrin is definitely a slit pore protein expressed between foot processes of podocytes in the glomeruli and is critical in keeping permeability and avoiding proteinuria15,16. Mutation of the nephrin gene prospects to congenital nephrotic syndrome of the Finnish type, which specifically affects the kidney and is characterized by massive proteinuria17. In addition to glomerular filtration barrier, mesangial cells and their matrix form the central stalk of the glomerulus and are portion of a functional unit, which interacts closely with endothelial cells and podocytes. Alterations Vorinostat (SAHA) in one cell type can create changes in the others18. We have demonstrated that in aldosterone-salt-induced hypertension, Ac-SDKP significantly decreased renal cell proliferation and renal fibrosis but only slightly reduced glomerular and tubular injury12; however, we did not examine the underlying mechanism(s) or test renal function. In the present study, we tested the hypothesis that Ac-SDKP helps prevent and reverses renal albuminuria and dysfunction in 5/6Nx-induced hypertension by reducing inflammatory cell infiltration and renal fibrosis and increasing nephrin protein. MATERIALS AND METHODS Animals Male Sprague Dawley rats (Charles River Laboratories, Wilmington, MA) weighing 275-300 g were housed in an air-conditioned space having a 12-hr light/dark cycle and received standard laboratory rat chow and tap water. They were allotted 7 days to adjust to their fresh environment. Prior to all Vorinostat (SAHA) surgical procedures, rats were given analgesia (butorphanol 2 mg/kg s.c.) and anesthesia (sodium pentobarbital 50 mg/kg i.p.). This study was authorized by the Henry Ford Hospital Institutional Animal Care and Use Committee (IACUC). Surgical procedure for 5/6 nephrectomy (5/6Nx) Rats were anesthetized and 5/6Nx was performed by unilateral nephrectomy plus ligation of lower and top renal arterial branches of the contralateral kidney having a 6-0 silk Vorinostat (SAHA) suture. Ligation was deemed successful when 2/3 of the kidney flipped dark reddish19. The sham-operated group underwent a similar surgical procedure except the suture round the renal artery was not tightened. An osmotic mini-pump filled with Ac-SDKP (800 g/kg/day time) or vehicle (0.01N acetic acid saline solution) was implanted s.c. between the shoulder blades. Experimental protocols Rats were randomly divided into two protocols: prevention and reversal. Prevention Protocol Rats received vehicle or Ac-SDKP beginning 7 days before surgery and continuing for 3 weeks. Group 1: Prevention sham Nx rats given vehicle (sham-vehicle/3 weeks, = 12). Group 2: Prevention 5/6Nx rats given vehicle (5/6Nx-vehicle/3 weeks, = 12). This group was also used like a control for the initial point of the reversal protocol. Group 3: Prevention 5/6Nx rats given Ac-SDKP (5/6Nx-Ac-SDKP/3 weeks, = 12). Reversal Protocol Rats received vehicle or Ac-SDKP beginning 3 weeks after surgery and continuing for up to 6 weeks. Group 4: Reversal sham Nx rats given vehicle (sham-vehicle/6 weeks, = 5). Group 5: Vorinostat (SAHA) Reversal 5/6Nx rats given vehicle (5/6Nx-vehicle/6 weeks, = 10). Group 6: Reversal 5/6Nx rats given Ac-SDKP (5/6Nx-Ac-SDKP/6 weeks, = 7). Group 2 of the Prevention Protocol (5/6Nx-vehicle/3 weeks) was used as the treatment baseline.