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CKD progression depends on the activation of an intricate set of hemodynamic and inflammatory mechanisms, promoting renal leukocyte infiltration, inflammation and fibrosis, leading to renal function loss. There are currently no specific drugs to detain renal fibrogenesis, which is a common end-point for different nephropathies. Clinical therapy for CKD is mostly based on the management of hypertension and proteinuria, partially achieved with renin-angiotensin-aldosterone system (RAAS) blockers, and the control of inflammation by immunosuppressive drugs. The aim of the present study was to verify if the administration of tamoxifen (TAM), an estrogen receptor modulator, clinically employed in the treatment of breast cancer and predicted to exert antifibrotic effects, would promote additional benefits when associated to a currently used therapeutic scheme for the conservative management of experimental CKD. Wistar rats underwent the NAME model of hypertensive nephrosclerosis, obtained by daily oral administration of a nitric oxide synthesis inhibitor, associated to dietary sodium overload. The therapeutic association of TAM to losartan (LOS), and mofetil mycophenolate (MMF) effectively reduced the severe hypertension, marked albuminuria and glomerular damage exhibited by NAME animals. Moreover, the association also succeeded in limiting renal inflammation in this model, and promoted further reduction of ECM interstitial accumulation and renal fibrosis, compared to the monotherapies. According to our results, the association of TAM to the currently used conservative treatment of CKD added significant antifibrotic effects both in vivo and in vitro, and may represent an alternative to slow the progression of chronic nephropathy., (© 2023. Springer Nature Limited.)

We conducted a multicenter, randomized, double-blind, placebo-controlled, phase IIb/III study (CASSIOPEIR) using a renal composite endpoint (i.e., doubling of SCr or end-stage renal disease) in seven Asian countries/region. CASSIOPEIR compared TRK-100STP (120 μg and 240 μg) with placebo in patients with non-diabetic CKD patients with primary glomerular disease or nephrosclerosis (n = 892). However, the superiority of TRK-100STP over placebo was not observed. A prior phase II study on which the Phase IIb/III study design was based included only Japanese patients. We therefore evaluated TRK-100STP efficacy and safety in a subgroup of Japanese patients using the CASSIOPEIR dataset. As the timing of treatment initiation is important in CKD, we conducted additional subgroup analyses based on the baseline serum creatinine (SCr) and eGFR. ITT analysis was performed in a Japanese subgroup (n = 339) in which the primary endpoint was the first occurrence of renal composite endpoint. Significant differences were observed for TRK-100STP 240 μg vs. placebo (P = 0.0493; HR 0.69 [95% CI: 0.47, 1.00]), but no significant difference was observed between TRK-100 120 μg and placebo (P = 0.3523; HR 0.85). More prominent improvement was observed with TRK-100STP 240 μg vs. placebo for baseline SCr  < 3.0 mg/dL (P = 0.0031; HR 0.43); SCr < 3.5 mg/dL (P = 0.0237, HR 0.59); and eGFR ≥ 10 mL/min/1.73 m 2 (P = 0.0339, HR0.67), respectively. No significant changes in urinary albumin/creatinine ratio and blood pressure were observed. TRK-100STP was generally well tolerated and most adverse drug reactions were mild or moderate in severity. In conclusion, in the Japanese subgroup of CASSIOPEIR, TRK-100STP 240 μg/day significantly improved the renal composite endpoint compared with placebo, with greater efficacy in subjects with SCr < 3.5 or eGFR ≥ 10 mL/min/1.73 m 2 ., (© 2020 The Authors. Therapeutic Apheresis and Dialysis published by John Wiley & Sons Australia, Ltd on behalf of International Society for Apheresis, Japanese Society for Apheresis, and Japanese Society for Dialysis Therapy.)

Background: Activation of renal fibroblasts is a critical mechanism in the process of renal fibrosis. As a commonly used herbal formula, Shenkang (SK) has been found to attenuate renal fibrosis and renal parenchyma destruction. However, the effect of SK on renal fibroblast activation in unilateral ureteral obstruction (UUO) mice and its molecular mechanism remain undetermined. The present study was performed to elucidate the effect of SK on renal fibroblast activation and renal fibrosis, as well as the potential underlying mechanism, in both NRK-49F cells and UUO mice., Methods: NRK-49F cells were stimulated with 10 ng/ml TGF-β1 for 48 h. After SK treatment, the CCK-8 method was used to evaluate cell viability. Thirty-six C57BL/6 mice were randomly divided into the sham group, UUO group, angiotensin receptor blocker (ARB) group, and SK high-, moderate- and low-dose groups. UUO was induced in mice except those in the sham group. Drugs were administered 1 day later. On the 13th day, the fractional anisotropy (FA) value was determined by MRI to evaluate the degree of renal fibrosis. After 14 days, serum indexes were assessed. Hematoxylin and eosin (HE) and Sirius red staining were used to observe pathological morphology and the degree of fibrosis of the affected kidney. Western blotting and PCR were used to assess the expression of related molecules in both cells and animals at the protein and gene levels., Results: Our results showed that SK reduced extracellular matrix (ECM) and α-smooth muscle actin (α-SMA) expression both in vitro and in vivo and attenuated renal fibrosis and the pathological lesion degree after UUO, suppressing JAK2/STAT3 activation. Furthermore, we found that SK regulated the JAK2/STAT3 pathway regulators peroxiredoxin 5 (Prdx5) in vitro and suppressor of cytokine signaling protein 1 (SOCS1) and SOCS3 in vivo., Conclusions: These results indicated that SK inhibited fibroblast activation by regulating the JAK2/STAT3 pathway, which may be a mechanism underlying its protective action in renal fibrosis.

TRK-100STP, a sustained-release preparation of the orally active prostacyclin analogue beraprost sodium, targets renal hypoxia. This study aimed to show the superiority of TRK-100STP over placebos in patients with chronic kidney disease (with either primary glomerular disease or nephrosclerosis) to determine the recommended dose. CASSIOPEIR (Chronic Renal Failure Asian Study with Oral PGI 2 Derivative for Evaluating Improvement of Renal Function) was a randomized, double-blind, placebo-controlled study conducted at 160 sites in seven Asia-Pacific countries and regions. Eligible patients (n = 892) were randomized to TRK-100STP 120, 240 μg, or placebo for a treatment period of up to 4 years. The primary efficacy endpoint was time to first occurrence of a renal composite: doubling of serum creatinine or occurrence of end-stage renal disease. No significant differences were observed in composite endpoints between TRK-100STP and placebo (P = 0.5674). Hazard ratios (95% CI) in the TRK-100STP 120 and 240 μg vs. placebo groups were 0.98 (0.78, 1.22) and 0.91 (0.72, 1.14), respectively. The overall incidence of adverse events and adverse drug reactions was comparable between treatment arms., (© 2019 International Society for Apheresis, Japanese Society for Apheresis, and Japanese Society for Dialysis Therapy.)

Transient receptor potential canonical type 6 (TRPC6) is a nonselective receptor-operated cation channel that regulates reactive fibrosis and growth signaling. Increased TRPC6 activity from enhanced gene expression or gain-of-function mutations contribute to cardiac and/or renal disease. Despite evidence supporting a pathophysiological role, no orally bioavailable selective TRPC6 inhibitor has yet been developed and tested in vivo in disease models. Here, we report an orally bioavailable TRPC6 antagonist (BI 749327; IC 50 13 nM against mouse TRPC6, t 1/2 8.5-13.5 hours) with 85- and 42-fold selectivity over the most closely related channels, TRPC3 and TRPC7. TRPC6 calcium conductance results in the stimulation of nuclear factor of activated T cells (NFAT) that triggers pathological cardiac and renal fibrosis and disease. BI 749327 suppresses NFAT activation in HEK293T cells expressing wild-type or gain-of-function TRPC6 mutants (P112Q, M132T, R175Q, R895C, and R895L) and blocks associated signaling and expression of prohypertrophic genes in isolated myocytes. In vivo, BI 749327 (30 mg/kg/day, yielding unbound trough plasma concentration ∼180 nM) improves left heart function, reduces volume/mass ratio, and blunts expression of profibrotic genes and interstitial fibrosis in mice subjected to sustained pressure overload. Additionally, BI 749327 dose dependently reduces renal fibrosis and associated gene expression in mice with unilateral ureteral obstruction. These results provide in vivo evidence of therapeutic efficacy for a selective pharmacological TRPC6 inhibitor with oral bioavailability and suitable pharmacokinetics to ameliorate cardiac and renal stress-induced disease with fibrosis., Competing Interests: Conflict of interest statement: D.M., J.F.D., L.P., D.W., G.R., S.M.W., S.Z., H.S.Q, J.J.K, A.S., and S.S.P. are full-time employees of Boehringer Ingelheim Pharmaceuticals, Inc. M.M, M.R.N, A.B., and C.S. were full-time employees of Boehringer Ingelheim Pharmaceuticals, Inc. A.B. and M.R.N. are listed as coinventors on a US provisional patent application filed by Boehringer Ingelheim Pharmaceuticals, Inc. relevant to this work. J.F.D., N.Z., D.d.C., X.Z., N.T.B., J.A.C., D.P.H., and M.M.M. were employees of Hydra Biosciences, and received options. This work was supported in part by Boehringer Ingelheim Pharmaceuticals, Inc.

Background: Although histone acetylation, an epigenetic modification, has been reported to be related to the progression of various diseases, its involvement in nephrosclerosis is unclear., Methods: Dahl salt-sensitive rats were used as a model of nephrosclerosis in this study. The rats were divided into three groups: (i) normal-salt diet group, (ii) high-salt diet group (HS), and (iii) HS administered daily with curcumin, a histone acetyltransferase inhibitor (HS+C). At 6 weeks after the treatment, the kidneys were dissected. Morphologic changes were assessed by Masson's trichrome staining. The number of macrophages, fibroblasts and the cells expressing acetylated histone H3 at Lys 9 (H3K9) were assessed by immunohistochemistry., Results: Although both HS and HS+C rats revealed a marked increase in systolic blood pressure, serum creatinine was increased only in HS rats at 6 weeks. In the HS rats, nephrosclerosis was induced, accompanying a significant accumulation of macrophages and fibroblasts. The inflammation and fibrosis was markedly suppressed in the HS+C group. The level of histone acetylation at Lys 9 was enhanced in the HS rats, whereas curcumin administration suppressed the histone acetylation. Moreover, in the HS rats, interleukin-6 gene expression was associated with acetylated H3K9, as revealed by chromatin immunoprecipitation assay., Conclusions: Our results suggested that curcumin ameliorates nephrosclerosis via suppression of histone acetylation, independently of hypertension., (© The Author 2016. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.)

Potent-selective peptidomimetic inhibitors of tissue transglutaminase (TG2) were developed through a combination of protein-ligand docking and molecular dynamic techniques. Derivatives of these inhibitors were made with the aim of specific TG2 targeting to the intra- and extracellular space. A cell-permeable fluorescently labeled derivative enabled detection of in situ cellular TG2 activity in human umbilical cord endothelial cells and TG2-transduced NIH3T3 cells, which could be enhanced by treatment of cells with ionomycin. Reaction of TG2 with this fluorescent inhibitor in NIH3T3 cells resulted in loss of binding of TG2 to cell surface syndecan-4 and inhibition of translocation of the enzyme into the extracellular matrix, with a parallel reduction in fibronectin deposition. In human umbilical cord endothelial cells, this same fluorescent inhibitor also demonstrated a reduction in fibronectin deposition, cell motility, and cord formation in Matrigel. Use of the same inhibitor in a mouse model of hypertensive nephrosclerosis showed over a 40% reduction in collagen deposition., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Previous studies have indicated that macrophage phenotype diversity is involved in the progression of renal fibrosis. However, the factors facilitating M1 or M2 phenotypes and the function of these polarized macrophages in kidney injury and fibrosis remain largely unknown. In the present study, we found that macrophages accumulated in the kidney interstitium exhibited mainly as the M1 phenotype at the early stage of unilateral ureter obstruction (UUO). High-mobility group box 1 (HMGB1) protein expressed and released from tubular epithelial cells and interstitial macrophages was essential for the M1 macrophage transition. HMGB1 significantly induced the expression of the M1 marker inducible nitric oxide synthase while decreasing the M2 marker IL-10 in macrophages. Moreover, a glycyrrhizic acid derivative, a blocker of HMGB1 release, reduced UUO-mediated kidney injury and ameliorated UUO-induced renal fibrosis. Interestingly and importantly, UUO caused a low pH value in the urine accumulated in the obstructed ureter, and the acidified urine induced HMGB1 release from tubular epithelial cells and macrophages in vitro. Our data demonstrate that HMGB1 is an essential contributor in facilitating M1 polarization at the early stage of UUO. Inhibition of HMGB1 release may alter macrophage phenotype and contribute to the protection of kidney tissue from injury and fibrosis., (Copyright © 2015 the American Physiological Society.)

In kidney transplantation, renal ischemia and reperfusion injury was one of the leading factors to the development of renal fibrosis, which was the main cause of graft loss. The fibrogenic changes were associated with the long term inflammation elicited by ischemia and reperfusion injury. In the present study, we investigated the role of the Picroside II, the main active constituents of the extract of picrorrhiza scrophulariiflora roots, in attenuating renal fibrosis in a renal ischemia and reperfusion injury model. We induced ischemia and reperfusion injury in kidneys treated with or without Picroside II. We observed that inflammation and tissue fibrosis were increased in ischemia and reperfusion injury group compared to Picroside II group, however, these changes were significantly decreased by the treatment with Picroside II. We concluded that Picroside II can protect the ischemic kidney against renal fibrosis and its mechanism may be through the inhibition of the long term inflammation.

This study assessed the urinary albumin/creatinine ratio (ACR) and uric acid metabolism in 70 hypertensive patients with chronic kidney disease in whom urinary ACR had remained ≥30 mg/g under the treatment of the L-type calcium channel blocker amlodipine. Three months after switching to the N/L-type calcium channel blocker cilnidipine, blood pressure (BP) did not change; however, urinary ACR significantly decreased with cilnidipine. Serum uric acid levels showed no significant change. In cases where uric acid production had been high (urinary uric acid/creatinine ratio ≥0.5), the urinary uric acid/creatinine ratio decreased significantly after cilnidipine treatment, suggesting that cilnidipine can suppress excessive uric acid formation. These results suggest that switching from amlodipine to cilnidipine results in a significant reduction in urinary ACR as well as significant reduction in uric acid production. Thus, cilnidipine is more useful than amlodipine in improving albuminuria and uric acid metabolism in hypertensive patients with chronic kidney disease., (©2014 Wiley Periodicals, Inc.)

Background: Chronic kidney disease (CKD) is public health concern even in Asian countries. TRK-100STP, a sustained release tablet of an orally-active prostacyclin analogue, beraprost sodium, is suggested to suppress worsening of some parameters of renal filtration function, containing in slope of 1/serum creatinine (1/SCr) vs. time in a phase II clinical trial., Methods/design: We describe the design of the phase IIb/III trial of TRK-100STP, CASSIOPEIR (CRF Asian Study with Oral PGI2 derivative for Evaluating Improvement of Renal function) conducted in approximately 160 centers in China, Hong Kong, Japan, Malaysia, Republic of Korea, Taiwan, and Thailand. A total of 750 patients (n = 250 per group) with primary glomerular disease or nephrosclerosis were planned to be enrolled. Patients were randomized into one of three treatment groups in a double-bind, placebo-controlled manner: TRK-100STP 60 μg b.i.d.; TRK-100STP 120 μg b.i.d.; or placebo. The treatment period is planned to last 2 to 4 years. The primary efficacy endpoint is the renal composite endpoint including doubling of SCr and ESRD (dialysis induction, renal transplantation, or increase in SCr to ≥ 6.0 mg/dL)., Discussion: This trial targeting CKD patients is designed to (a) demonstrate the superiority of TRK-100STP over placebo using renal composite endpoints, (b) determine the recommended clinical dose, and (c) assess the safety of TRK-100STP in this population and setting., Trial Registration: ClinicalTrials.gov Identifier: NCT01090037.

Background: The aim of this study was to investigate the antialbuminuric and antihypertensive effects of aliskiren by monitoring home blood pressure (BP) in comparison with the effects of the angiotensin receptor blocker (ARB) valsartan in patients with hypertensive nephrosclerosis and albuminuria., Methods: We conducted an open-label, randomized trial to compare the effects of aliskiren with those of valsartan. Patients with BP <150/90 mmHg, an estimated glomerular filtration rate of 90-30 mL/min/1.73 m(2), and albuminuria >30 mg/g, despite treatment with a 160 mg daily dose of valsartan, were randomly assigned to the following two groups: the aliskiren group, who switched from 160 mg/day valsartan to 150 mg/day aliskiren, which was later increased to 300 mg/day (n = 20); and the valsartan group, who continued with 160 mg/day valsartan (n = 20)., Results: After 12 weeks of treatment, although there was no significant difference in clinic BP between groups, a significant reduction in morning and evening systolic BP was observed in the aliskiren group. The decrease in albuminuria in the aliskiren group was significantly better than that in the valsartan group, and a significant correlation was noted between the change in morning systolic BP and the change in albuminuria in the aliskiren group (r = 0.564, P = 0.0084)., Conclusion: We showed that aliskiren treatment leads to a greater reduction in albuminuria and home systolic BP values than valsartan in patients with nephrosclerosis. We propose that aliskiren therapy should be considered as a therapeutic modality to complement ARBs in hypertensive patients with nephrosclerosis.

Tubulointerstitial macrophage infiltration is a hallmark of chronic kidney disease involved in the progression of renal fibrosis. Pirfenidone is a newly identified antifibrotic drug, the potential mechanism of which remains unclear. The aim of this study was to investigate the effects of pirfenidone on M1/M2 macrophage infiltration in nephrectomized rats. Nephrectomized rats were treated with pirfenidone by gavage for 12 wk. Twenty-four hour urinary protein, N-acetyl-β-D-glycosaminidase (NAG) activity, systolic blood pressure, and C-reactive protein were determined. Paraffin-embedded sections were stained for CD68, CCR7, and CD163 macrophages. Monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1α (MIP-1α), as well as M1 and M2 macrophages secretory markers, were evaluated by real-time RT-PCR and Western blotting analysis. Pirfenidone significantly improved the elevated proteinuria and NAG activity from week 2 onward after surgery. Pirfenidone attenuated interstitial fibrosis and decreased expression of fibrotic markers including transforming growth factor-β(1), connective tissue growth factor, α-smooth muscle actin, fibronectin, and fibroblast-specific protein-1. Pirfenidone significantly decreased the infiltrating macrophages. The number of M1 and M2 macrophages was significantly lower after pirfenidone treatment. MCP-1 and MIP-1α were increased in nephrectomized rats at mRNA and protein levels. Pirfenidone treatment significantly inhibited their expression. The TNF-α, IL-6, and nitric oxide synthases-2 expressed by M1 macrophages were increased in nephrectomized rats, and pirfenidone significantly attenuated their expression. Pirfenidone treatment also significantly decreased arginase-1, dectin-1, CD206, and CD86 expressed by M2 macrophages. Thus pirfenidone inhibits M1 and M2 macrophage infiltration in 5/6 nephrectomized rats, which suggests its efficacy in the early and late periods of renal fibrosis.

Stroke-prone spontaneously hypertensive (SHRsp) rats develop severe hypertension resulting in renal injury. We investigated apoptosis inhibitor of macrophages (AIM) expression in nephrosclerotic rats and the involvement of AIM in olmesartan (OLM)- and azelnidipine (AZN)-induced decreases in the number of macrophages infiltrating the kidney. We randomly assigned 20-week-old male SHRsp rats to receive one of the following substances every day for 12 weeks: water (vehicle), hydralazine (HYD), OLM, or AZN. Renal damage was assessed by Masson trichrome staining. Expressions of ED-1, AIM, and oxidized low-density lipoprotein (oxLDL) were immunohistochemically detected. Apoptosis was analyzed by terminal deoxynucleotidyl transferase deoxyuridine triphosphate (dUTP) nick-end labeling (TUNEL) staining. All treatment groups showed significantly less renal interstitial fibrosis than the vehicle group. AZN and OLM groups had significantly fewer AIM-expressing cells than the HYD and vehicle groups. The ratios AIM-positive cells/ED-1-positive macrophages and TUNEL-positive cells/ED-1-positive macrophages in the AZN and OLM groups were lower and higher, respectively, than the the HYD and vehicle groups. oxLDL expression in the renal interstitium was significantly lower in treatment groups compared to vehicle group. OLM and AZN inhibited interstitial fibrosis progression in SHRsp rats by suppressing AIM expression in macrophages, followed by reducing the number of infiltrating macrophages.

Tolvaptan is a highly selective and orally effective arginine vasopressin V2 receptor antagonist, and is potentially useful for the treatment of heart failure (HF) patients. However, the renoprotective effect of long-term tolvaptan therapy and its underlying mechanisms remain unknown. We evaluated the effects of chronic treatment with tolvaptan on renal dysfunction, podocyte injury, inflammation, oxidative stress, Rho-kinase, epithelial-mesenchymal transition (EMT), and the extracellular signal-regulated protein kinase (ERK1/2) pathway in the renal cortex of Dahl salt-sensitive hypertensive (DS) rats with end-stage severe HF. DS and Dahl salt-resistant rats were fed a high-salt diet at 6 weeks of age. DS rats were treated with vehicle and tolvaptan (0.05% concentration in diet) from the age of 11 to 18 weeks. Vehicle-treated DS rats developed proteinuria, renal dysfunction, glomerulosclerosis, and interstitial fibrosis, which were ameliorated by tolvaptan without changing blood pressure. Decreased expression of nephrin and podocin and increased desmin-positive area in failing rats were restored by tolvaptan. Upregulation of NAD(P)H oxidase p22(phox), p47(phox), and gp91(phox), EMT markers such as transforming growth factor-β1, vimentin, and fibronectin expression, and Rho-kinase and ERK1/2 phosphorylation in DS rats were significantly suppressed by tolvaptan. Tolvaptan administration resulted in significant inhibition of tumor necrosis factor-α and monocyte chemoattractant protein-1 expression, and nuclear factor-κB phosphorylation. We concluded that long-term tolvaptan therapy may improve renal dysfunction, glomerulosclerosis, podocyte injury, and inflammation associated with oxidative stress, as well as EMT, ERK, and the Rho-kinase pathway in the failing heart of DS rats. Thus, tolvaptan may be a therapeutic strategy for end-stage severe HF.

Diabetic nephropathy is one of the most common microvascular complications of diabetes and the leading cause of end-stage renal disease. In the present study, we investigated the renoprotective effect of the aqueous extract of Portulaca oleracea (AP) on diabetic nephropathy accelerated by renal fibrosis and inflammation in type 2 diabetic db/db mice. The mice were treated with AP (300 mg/kg/day, p.o.) for ten weeks to examine the long-term effects on diabetic nephropathy and renal dysfunction. We found that AP treatment markedly lowered blood glucose to 412 ± 11.4 mg/dl and plasma creatinine level to 2.3 ± 0.8 mg/dl compared to db/db mice (p < 0.05, p < 0.01, respectively). This study also showed that treatment with AP significantly decreased water intake and urine volume in diabetic db/db mice (p < 0.05). In immunohistological study, the renal expression of transforming growth factor-β1 (TGF-β1), advanced glycation end products (AGE), and intercellular adhesion molecule (ICAM)-1 markedly increased in the renal cortex of untreated db/db mice (p < 0.01). In contrast, AP treatment significantly reduced these expressions to 50 ± 2.1%, 48 ± 2.8%, 61 ± 1.1%, respectively (p < 0.01). Furthermore, NF-κB p65 activation in renal tissues markedly increased in untreated db/db mice, which was significantly suppressed by AP treatment. Taken together, these findings suggest that AP attenuates diabetic nephropathy through inhibition of renal fibrosis and inflammation in db/db mice.

Benidipine inhibits both L- and T-type Ca channels, and has been shown to dilate the efferent arterioles as effectively as the afferent arterioles. In this study, we conducted an open-label and randomized trial to compare the effects of benidipine with those of amlodipine on blood pressure (BP), albuminuria and aldosterone concentration in hypertensive patients with mild-to-moderate stage chronic kidney disease (CKD). Patients with BP ≥ 130/80 mm Hg, with estimated glomerular filtration rate (eGFR) of 30-90 ml min(-1) per 1.73 m(2), and with albuminuria>30 mg per g creatinine (Cr), despite treatment with the maximum recommended dose of angiotensin II receptor blockers (ARBs) were randomly assigned to two groups. Patients received either of the following two treatment regimens: 2 mg per day benidipine, which was increased up to a dose of 8 mg per day (n=52), or 2.5 mg per day amlodipine, which was increased up to a dose of 10  mg per day (n=52). After 6 months of treatment, a significant and comparable reduction in the systolic and diastolic BP was observed in both groups. The decrease in the urinary albumin to Cr ratio in the benidipine group was significantly lower than that in the amlodipine group. Although plasma renin activity was not different in the two groups, plasma aldosterone levels were significantly decreased in the benidipine group. Moreover, urinary Na/K ratio was significantly decreased in the benidipine group but remained unchanged in the serum. It may be concluded that benidipine results in a greater reduction of plasma aldosterone and albuminuria than amlodipine, and that these effects are independent of BP reduction.

Background: African-Americans are likely to develop hypertension and hypertensive nephrosclerosis. This grave prognosis, coupled with familial aggregation of end-stage renal disease (ESRD) in Blacks, prompts a search for genetic risk factors for ESRD. Recent evidence implicates a crucial role for the sympathetic nervous system in progressive renal disease., Methods: We used the African-American Study of Kidney Disease to probe whether beta2-adrenergic receptor (ADRB2) predicts glomerular filtration rate (GFR) decline rate. A total of 580 participants were included. Baseline GFR was 51.2 +/- 0.5 ml/min/1.73 m2. Subjects were randomized in a 2 x 3 block design: to intensively lowered (MAP < or = 92 mm Hg) versus 'usual' (MAP = 102-107 mm Hg) blood pressure goal groups, and also divided by three randomized antihypertensive drugs (ramipril, metoprolol, or amlodipine). We scored 4 SNPs at the ADRB2 locus., Results: Haplotypes at ADRB2 predicted chronic GFR decline rate, GFR declined more slowly in individuals with haplotype-1 (-804G-->173T-->16Gly-->27GIn), and faster in those who carried haplotype-3 (-804G-->173T-->16Arg-->27Gln). ADRB2 genotype interacted with antihypertensive drug class to influence GFR slope (p = 0.001-0.037). We extended our findings to an independent case/control sample of Black hypertensive ESRD, in which we found that variant Gly16Arg that tagged the GFR slope-determining ADRB2 haplotype also conferred risk for the ESRD trait in Blacks., Conclusions: The GFR decline/progression rate in hypertensive renal disease is controlled in part by genetic variation within the adrenergic pathway., (Copyright 2010 S. Karger AG, Basel.)

Background: African Americans have a disproportionate burden of hypertension and comorbid disease. Pharmacogenetic markers of blood pressure response have yet to be defined clearly. This study explores the association between G-protein-coupled receptor kinase type 4 (GRK4) variants and blood pressure response to metoprolol among African Americans with early hypertensive nephrosclerosis., Methods: Participants from the African American Study of Kidney Disease and Hypertension (AASK) trial were genotyped at three GRK4 polymorphisms: R65L, A142V, and A486V. A Cox proportional hazards model, stratified by gender, was used to determine the relationship between GRK4 variants and time to reach a mean arterial pressure (MAP) of 107 mm Hg, adjusted for other predictors of blood pressure response. Potential interactions between the three polymorphisms were explored by analyzing the effects of gene haplotypes and by stratifying the analysis by neighboring sites., Results: The hazard ratio with 95% confidence interval by A142V among men randomized to a usual MAP (102-107 mm Hg) was 1.54 (1.11-2.44; P = 0.0009). The hazard ratio by A142V with R65/L65 or L65/L65 was 2.14 (1.35-3.39; P = 0.001). Haplotype analyses were consistent but inconclusive. There was no association between A142V and blood pressure response among women., Conclusions: Results suggest a sex-specific relationship between GRK4 A142V and blood pressure response among African-American men with early hypertensive nephrosclerosis. Men with a GRK4 A142 were less responsive to metoprolol if they had a GRK4 L65 variant. The effect of GRK4 variants and blood pressure response to metoprolol should be studied in larger clinical trials.

Background: In this study, we tested the hypothesis that long-term Rho-kinase inhibition would reverse nitro-L-arginine methyl ester-exacerbated nephrosclerosis in spontaneously hypertensive rats and attempted to elucidate the mechanism involved., Methods: Five groups (each n = 8) were studied: untreated spontaneously hypertensive rats; nitro-L-arginine methyl ester (50 mg/l in drinking water, for 3 weeks)-treated spontaneously hypertensive rats; nitro-L-arginine methyl ester with fasudil (10 mg/kg/day)-treated spontaneously hypertensive rats; nitro-L-arginine methyl ester for 3 weeks followed by fasudil for 3 weeks-treated spontaneously hypertensive rats (same doses), and nitro-L-arginine methyl ester for 3 weeks followed by untreated for 3 weeks. We examined renal function, blood pressure, histological features, oxidative stress markers, and mRNA expression in the renal cortex., Results: Nitro-L-arginine methyl ester-treated spontaneously hypertensive rats had higher blood pressure, proteinuria, and serum creatinine and lower creatinine clearance, urinary NO3/NO2 ratio, and urinary cGMP excretion compared with control spontaneously hypertensive rats (all Ps < 0.05). Nitro-L-arginine methyl ester-treated spontaneously hypertensive rats also had increased free radical metabolites and abnormal morphological findings with increased nicotinamide adenine dinucleotide phosphate oxidase activity, phosphorylation of myosin phosphatase targeting subunit-1, and mRNA expression of RhoA, RhoB, RhoC, collagen I and III, transforming growth factor-beta, nicotinamide adenine dinucleotide phosphate subunit, endothelial nitric oxide synthase, plasminogen activator inhibitor, and intercellular adhesion molecule-1 in the renal cortex compared with control spontaneously hypertensive rats. Long-term co-treatment with fasudil slightly improved these indices, but most of them were not statistically significant. Late fasudil treatment significantly improved kidney function, morphological changes, and alterations of mRNA expression in the renal cortex, although late untreated controls did not show any improvement., Conclusion: These results suggest that Rho-kinase inhibition partly reverses hypertensive glomerulosclerosis. The renoprotective effect of the Rho-kinase inhibitor may have multiple mechanisms including inhibition of extracellular matrix production, oxidative stress, adhesion molecule production, and antifibrinolysis.

There is increasing evidence for a role of somatic cellular senescence in physiological aging but also in injury and disease. Cell cycle inhibitor p16(INK4a) is the key mediator for stress and aberrant signaling induced senescence. Here we report that elevated blood pressure markedly induced p16(INK4a) expression in rat kidneys and hearts, as well as in human kidneys. In kidneys from deoxycorticosterone acetate-salt-treated rats, p16(INK4a) induction was found in tubular, glomerular, interstitial, and vascular cells and correlated with the typical histopathologic features of hypertensive target organ damage. p16(INK4a) expression also correlated with phospho-p38, a positive upstream regulator of p16(INK4a) expression. In left ventricles, increased p16(INK4a) expression was found in myocardium and cardiac arteries. Antihypertensive medication consistent of hydrochlorothiazide, hydralazine, and reserpine ameliorated the histopathologic changes and attenuated p16(INK4a) expression in kidneys of deoxycorticosterone acetate-salt-treated rats. Nonantihypertensive administration of spironolactone also reduced kidney damage and p16(INK4a) expression. p16(INK4a) induction was further observed in kidneys from hypertensive transgenic rats heterozygous for the mouse Ren-2 gene and was prevented by the angiotensin II type 1 receptor blocker losartan. In human kidney biopsies showing hypertensive nephrosclerosis, increased p16(INK4a) expression was found compared with age-matched normotensive control subjects. Thus, hypertension induces cellular senescence via p16(INK4a), possibly through p38, thereby contributing to hypertensive target organ damage. This detrimental effect can be overcome by different therapeutic drug strategies.

Objectives: We examined whether the Rho/Rho-kinase pathway is involved in the pathogenesis of nephrosclerosis in severely hypertensive rats and assessed the effects of long-term treatment with a Rho-kinase inhibitor, fasudil, on kidney function, histological findings, gene expressions, and survival. We also attempted to elucidate the mechanisms involved., Methods: We studied the following four groups: control Wistar-Kyoto rats (WKY), untreated salt-loaded spontaneously hypertensive stroke-prone rats (SHR-SP), low-dose fasudil (15 mg/kg per day)-treated SHR-SP, and high-dose fasudil (30 mg/kg per day)-treated SHR-SP. After 8 weeks' treatment, the effects of fasudil were examined., Results: Untreated SHR-SP were characterized by increased blood pressure without circadian variation, decreased kidney function, abnormal renal morphological findings, and increased messenger RNA expression levels of transforming growth factor beta, collagen I, collagen III, p40phox, p47phox, plasminogen activator inhibitor 1, and intracellular adhesion molecule 1 in the renal cortex, compared with WKY. Long-term high-dose fasudil treatment significantly improved renal function (serum creatinine -32%, creatine clearance +39%), proteinuria (-92%) and histological findings (glomerular injury score -57%, arteriolar injury score -55%, fibrous area -40%, ED-1-positive cells -43%) without changing blood pressure or circadian variation, compared with untreated SHR-SP. In addition, fasudil significantly improved increased mRNA expression levels in the renal cortex. Furthermore, high-dose fasudil significantly prolonged survival time compared with untreated SHR-SP (P < 0.01). Low-dose fasudil treatment improved these variables slightly, but did not affect most significantly., Conclusion: The Rho/Rho-kinase pathway participates in the pathogenesis of nephrosclerosis in SHR-SP independently of blood pressure-lowering activity, partly by upregulation of the gene expressions of extracellular matrix, oxidative stress, adhesion molecules, and antifibrinolysis.

Objective: Transforming growth factor (TGF)-beta is a critical factor in the progression of renal injury, regardless of the primary etiology. Such injury is characterized by glomerular sclerosis and tubulointerstitial fibrosis. To develop a ribozyme-based therapy for progressive renal diseases, we examined the effects of chimeric DNA-RNA hammerhead ribozyme targeting TGF-beta1 mRNA on glomerulosclerosis in salt-loaded, stroke-prone spontaneously hypertensive rats (SHR-SP) and salt-sensitive Dahl (Dahl-S) rats., Methods: The chimeric DNA-RNA ribozyme to TGF-beta1 was delivered by polyethylenimine to cultured mesangial cells from SHR-SP in vitro and to glomeruli in SHR-SP in vivo. The chimeric ribozyme reduced expression of TGF-beta1 mRNA and protein, which was accompanied by inhibition of expression of extracellular matrix molecules such as fibronectin and collagen type I in mesangial cells from SHR-SP in vitro., Results: One intraperitoneal injection of 200 microg of chimeric DNA-RNA ribozyme to TGF-beta1 in vivo markedly ameliorated thickening of capillary artery walls and glomerulosclerosis in salt-loaded SHR-SP and Dahl-S rats without a reduction in blood pressure. The chimeric ribozyme reduced expression of TGF-beta1 and connective tissue growth factor (CTGF) mRNAs in renal cortex in salt-loaded Dahl-S rats. Chimeric ribozyme to TGF-beta1 significantly reduced levels of protein in urine in the Dahl-S rats., Conclusion: These results suggest that chimeric DNA-RNA ribozyme to TGF-beta1 may be useful as a gene therapy for progressive tissue injury in a wide variety of renal diseases, including hypertensive nephrosclerosis.

Background: Patients with chronic kidney disease are at increased risk for cardiovascular (CV) events., Methods: We randomly assigned 1,094 African Americans with hypertensive nephrosclerosis (glomerular filtration rate [GFR], 20 to 65 mL/min/1.73 m(2) [0.33 to 1.08 mL/s]) to initial antihypertensive treatment with either: (1) a beta-blocker, metoprolol; (2) an angiotensin-converting enzyme inhibitor, ramipril; or (3) a dihydropyridine calcium channel blocker, amlodipine, and either a usual-blood pressure (BP) or low-BP treatment goal. Using a design powered to detect renal outcome differences, we compared the effect of treatment on the CV event rate (cardiac death, myocardial infarction, stroke, and heart failure) during a mean follow-up period of 4.1 years and determined baseline factors that predict CV outcomes., Results: Thirty-one patients died of CV disease (0.7%/patient-year), and 149 patients experienced at least 1 CV outcome (3.3%/patient-year). Overall, 202 CV events (4.5%/patient-year) occurred. The CV outcome rate was not related significantly to randomized interventions. In multivariable analyses, 7 baseline risk factors remained independently associated with increased risk for the CV composite outcome after controlling for age, sex, baseline GFR, and baseline proteinuria group: pulse pressure, duration of hypertension, abnormal electrocardiogram result, non-high-density lipoprotein cholesterol level, serum urea nitrogen level, urine protein-creatinine ratio, urine sodium-potassium ratio, and annual income less than 15,000 dollars., Conclusion: Neither randomized class of antihypertensive therapy nor BP level had a significant effect on the occurrence of CV events, possibly because of limited power. However, this analysis identifies unique and potentially modifiable CV risk factors in this high-risk cohort.

Objective: To explore the effect of p27 in the renal tubule on the process of renal interstitial fibrosis caused by unilateral ureteral obstruction (UUO) in rats, and to examine the expression changes of p27 after enalapril intervention and to interpret the anti-fibrotic mechanism., Methods: Ninety rats were randomly divided into the sham-operated group (SOR), UUO group,and UUO+enalapril treatment group [enalapril: 10 mg/(kg.d)]. The rats of each group were respectively sacrificed on 7, 14, 21 days post-operatively. The renal pathological changes were dynamically observed by HE. The expression and dynamic changes of p27 were detected by immunohistochemistry. The level of p27 mRNA were detected by RT-PCR., Results: The expression of p27 in renal tubular epithelial cells and p27 mRNA were strongly positive in the SOR group. With degree of interstitial fibrosis aggravating, the expression of p27 mRNA was gradually reducing. Enalapril could improve the expression of p27 on the 14th and 21st days after the UUO., Conclusion: (1) This study supports a causative role of p27 in the formation of fibrosis of renal mesenchyme in rats with UUO. (2) The anti-fibrotic mechanism of enalapril is partly the improvement of p27 expression.

Objective: To investigate the expression of P21 in renal interstitial fibrosis rats and the effect of enalapril on it., Methods: Sprague Dawley rats were randomly divided into 3 groups: a sham operation group,a unilateral urethral obstruction group, and an enalapril treatment group. The expression of P21 in renal tubular epithelial cells on the process was detected by immunohistochemistry at different time spots (7, 14, 21 d after UUO, sham-surgery or enalapril treatment). The expression of p21 mRNA was detected by reverse transcription-polymerase chain reaction (RT-PCR)., Results: Seven days after the surgery, significant differences were found in P21 expression between UUO and SOR renal tubular cells. With degree of interstitial fibrosis aggravating, P21 expression increased. Enalapril can inhibit its expression., Conclusion: In the kidney of UUO rats, P21 expression increased and enalapril possessed significant inhibitory effects on the procedure. P21 may participate in the pathogenesis of renal tubule-interstitial fibrosis.

A young female with essential hypertension developed progressive azotemia; renal biopsy showed hypertensive nephrosclerosis with considerable tubulointerstitial disease and cellular infiltration. The addition of mycophenolate mofetil (MMF) to her antihypertensive treatment resulted in a dramatic improvement of renal function during the following three months. When the patient discontinued MMF treatment, end-stage renal failure rapidly developed. This patient represents the first report of the beneficial use of MMF in non-immune chronic renal disease and demonstrates that significant functional improvement may be obtained with the addition of MMF to the treatment of hypertensive nephrosclerosis for patients in whom there is significant tubulointerstitial inflammatory infiltration.

The present study tested the effects of valsartan, an angiotensin II receptor blocker, on the progression of renal insufficiency in patients with nondiabetic renal diseases. The study subjects were 22 patients with nondiabetic renal diseases whose serum creatinine (Cr) ranged from 1.5 to 3.0 mg/dl. Valsartan (40-80 mg) or placebo was given once daily for 1 year each in a random crossover manner. In both periods, antihypertensive medications were titrated when the blood pressure was not lower than 140/90 mmHg. Blood sampling and urinalysis were performed bimonthly throughout the study periods. The average blood pressure was comparable between the valsartan and the placebo periods (130 +/- 9/86 +/- 6 vs. 131 +/- 8/86 +/- 6 mmHg). Serum Cr significantly increased from 1.9 +/- 0.5 to 2.3 +/- 0.8 mg/dl (p < 0.001) during the placebo period, but the change was insignificant in the valsartan period (2.1 +/- 0.6 to 2.2 +/- 0.9 mg/dl). The slope of decrease in the reciprocal of serum Cr was steeper in the placebo period than in the valsartan period (-0.064 +/- 0.070/year vs. -0.005 +/- 0.050/year, p < 0.01). During the valsartan period, urinary protein excretion was less than that during the placebo period (0.75 +/- 0.73 vs. 1.24 +/- 0.92 g/g Cr, p < 0.001). Serum K was significantly higher in the valsartan period than in the placebo period (4.6 +/- 0.5 vs. 4.4 +/- 0.5 mEq/l, p < 0.05); however, no patients discontinued taking valsartan as a result of hyperkalemia. It is possible that long-term treatment with an angiotensin II receptor blocker, valsartan, is effective at retarding the deterioration of renal function in patients with nondiabetic renal disease by a mechanism independent of blood pressure reduction.

Background/aims: Overexpression of transforming growth factor beta1-inducible gene h3 (betaig-h3) is associated with renal scarring in several models of renal disease. We investigated the inhibitory effect of pravastatin on betaig-h3 expression in a rat model of chronic cyclosporin A (CsA)-induced nephropathy., Methods: Adult Sprague Dawley rats kept on a low salt diet (0.05% sodium) were treated daily for 4 weeks with vehicle (olive oil, 1 ml/kg), CsA (15 mg/kg) or both CsA and pravastatin (20 mg/kg in drinking water). The effect of pravastatin on betaig-h3 expression was evaluated using in situ hybridization, immunohistochemistry, and immunoblotting. Functional parameters, histopathology (tubulointerstitial fibrosis, TIF, and arteriolopathy), and levels of transforming growth factor beta1 (TGF-beta1) and endothelial nitric oxide synthase were compared for the different treatment groups., Results: Co-administration of pravastatin significantly inhibited betaig-h3 mRNA production and gene expression within the tubulointerstitium of the CsA-treated kidneys, and this paralleled an attenuation of TIF (12.7 +/- 2.2 vs. 35.9 +/- 5.4%, p < 0.01 vs. CsA) and the expression of TGF-beta1 mRNA (279 +/- 40 vs. 719 +/- 85%, p < 0.01 vs. CsA). Pravastatin treatment reduced endothelial nitric oxide synthase protein levels and reversed the renal dysfunction caused by CsA. Neither CsA nor pravastatin affected total serum cholesterol or triglyceride levels in the treatment groups., Conclusion: Pravastatin thus effectively abrogated the upregulation of betaig-h3 gene expression and associated TGF-beta1 production, and this was associated with attenuated TIF in this model of chronic CsA-induced nephropathy.

The present study was performed to investigate the effects of the antiallergic drug tranilast on the development of diabetic nephropathy in streptozotocin (50 mg/kg)-induced diabetic spontaneously hypertensive rats (SHR). Diabetic SHR were given standard chow or chow containing tranilast at a dose of 1400 mg/kg for 24 weeks. The effects of tranilast on urinary albumin excretion, mesangial expansion, expression of transforming growth factor-beta (TGF-beta) and type I collagen mRNAs, number of anionic sites on the glomerular basement membrane (GBM), and urinary TGF-beta and 8-hydroxy-2'-deoxyguanosine (8-OHdG) excretion were assessed. Tranilast did not affect the blood glucose concentration or blood pressure in diabetic SHR. Urinary albumin excretion rate and creatinine clearance were markedly increased in diabetic SHR. Tranilast treatment decreased albuminuria and hyperfiltration. Tranilast inhibited the diabetes-induced expansion of mesangial and tuft areas, as well as the increase in urinary TGF-beta and 8-OHdG excretion, loss of anionic sites of GBM, and overexpression of TGF-beta as determined immunohistochemically. The levels of TGF-beta and type I collagen mRNA expression were increased in the renal cortex in untreated diabetic SHR at 24 weeks, as determined by real-time quantitative polymerase chain reaction. Tranilast treatment inhibited the up-regulation of TGF-beta and type I collagen mRNA expression by 65 and 36%, respectively, in diabetic SHR. In conclusion, tranilast decreased albuminuria by suppressing glomerular hyperfiltration, mesangial expansion, and loss of the charge barrier via regulation of extracellular matrix gene expression and oxidative stress. Tranilast may be clinically useful in the treatment of diabetic nephropathy.

We describe a hypertensive nephrosclerosis patient presenting with severe hyperkalemia due to a combination therapy of the angiotensin receptor blocker (ARB) candesartan and spironolactone despite mildly decreased renal function. Recently, ARBs are replacing the ACE inhibitors. The combined therapy with ARB and spironolactone will eventually become the standard regimen. The strict attention and close monitoring of serum potassium should be mandatory in combination therapy to prevent hyperkalemia. Assessment of trans-tubular potassium gradient (TTKG) and fractional excretion of potassium (FEK) before starting the therapy would help in identifying the patients at higher risk of developing hyperkalemia. Co-administration of thiazide or loop diuretics is recommended to reduce the risk of hyperkalemia.

Animal studies have shown that during high sodium intake aldosterone induces cardiac fibrosis and renal nephrosclerosis through activation of mineralocorticoid receptors. In the human heart mineralocorticoid receptors and activity of the enzyme 11beta-hydroxysteroid-dehydrogenase type 2, which is required for the activation of mineralocorticoid receptors by aldosterone, are both present. In clinical medicine the profibrotic effect of aldosterone has been related to diastolic dysfunction, arrhythmia and progression of cardiac and renal failure. The addition of an aldosterone receptor antagonist to optimal treatment in patients with heart failure causes a decrease in serum markers of collagen turnover and a decline in cardiac morbidity and mortality. These findings are a strong indication of a profibrotic effect of aldosterone in cardiac failure. Studies concerning the profibrotic effect of aldosterone in patients with primary hyperaldosteronism are contradictory and at the moment no data are available about a potential antifibrotic effect of aldosterone receptor antagonists in patients with impaired renal function.

Objective: To investigate the preventive and therapeutic effects of Astragalus and Angelica mixture A&A on renal tubulointerstitial fibrosis after unilateral ureteral obstruction UUO in rats and their mechanisms., Methods: UUO rats were randomly divided into Sham, UUO, A&A or ACEI groups. A&A, ACEI or the same amount of water was administered by gavage beginning 24 hours before UUO preparation and continued through ten days after UUO. Sera and the kidney tissues were collected from each group on the tenth day. Scr and BUN were measured. Trichrome staining, measurement of tubulo interstitial damage index and immunohistochemical studies localizing alpha-smooth muscle actin alpha-SMA , TGF-beta1, fibronectin FN , laminin LN were carried out., Results: In UUO rats, the tubular-interstitial damage index, the expressions of alpha-SMA, TGF-beta1, FN and LN were all increased compared with those of Sham group. The tubulo interstitial damage index had positive correlation with expressions of alpha-SMA, TGF-beta1, FN and LN. A&A significantly ameliorated deterioration of renal function, tubulo interstitial damage index and inhibited the over-expressions of alpha-SMA, TGF-beta1, FN and LN in UUO rats. These anti-fibrotic effects were similar to those affected by ACEI., Conclusion: In renal interstitial fibrosis-induced UUO rats, A&A retard the progression of renal fibrosis and renal function deterioration by inhibiting myofibroblasts and suppressing TGF-beta1 expression, which may consequently result in a decreased production of extracellular matrix.

Unlabelled: PURPOSE OF VIEW: A major clinical trial and a meta-analysis completed within the past year addressed the issue of renal disease progression after blood pressure-lowering treatment in patients with hypertension and diminished renal function. Important human and animal studies have addressed mechanistic issues regarding renal disease progression. These advances warrant detailed discussion., Recent Findings: The African American Study of Kidney Disease and Hypertension Study Group trial found that an angiotensin-converting enzyme inhibitor was superior to a calcium antagonist or beta-blocker in ameliorating renal disease progression in African-Americans. An attempt to show an advantage of lowering blood pressure to less than 130/80 compared with 140/90 mmHg showed no additional benefit. However, a meta-analysis of 2000 non-diabetic hypertensive patients suggested that lower blood pressures are beneficial, particularly in individuals with proteinuria. An autopsy study of hypertensive and normotensive individuals dying in motor vehicle accidents supported the theory that hypertensive individuals have fewer, albeit larger, glomeruli than normotensive individuals. An animal study in sheep showed similar findings in sheep born to dams given dexamethasone compared with placebo. Animal studies involving stress, immunity, and cytokines shed further light on the mechanisms. The transfer of Smad7 ameliorated renal damage in rats with ureteral obstruction and fibrosis., Summary: Guidelines suggest prescribing angiotensin-converting enzyme inhibitor or angiotensin 1 receptor blocker therapy to all patients with decreased renal function and hypertension with or without diabetes. The possibility that essential hypertension involves reduced glomerular numbers received support, as well as the theory of prenatal imprinting. Progress is being made regarding basic mechanisms and novel therapies.

Background: The renin-angiotensin-aldosterone system participates importantly in the progression of hypertensive renal disease. Angiotensin-converting enzyme inhibitors or angiotensin II receptor antagonists have been demonstrated to afford renoprotection in L-NAME-exacerbated nephrosclerosis in SHR rats. This study was designed to examine the effects of the aldosterone antagonist eplerenone on systemic and renal hemodynamics, glomerular dynamics, renal function and histopathology in L-NAME/SHR, and determine whether aldosterone antagonism would enhance the effectiveness of ACE inhibition., Methods: Six groups of 20-week-old SHR were studied using renal micropuncture and histopathological techniques after 3 weeks of treatment: SHR control (tapwater, n = 10); SHR + eplerenone (101 +/- 8.3 mg/kg/day, n = 10); SHR + L-NAME (5.0 +/- 0.12 mg/kg/day, n = 9); SHR + L-NAME + eplerenone (n = 8); SHR + L-NAME + lisinopril (3 mg/kg/day, n = 9), and SHR + L-NAME + eplerenone + lisinopril (n = 9)., Results: L-NAME-treated SHR developed massive proteinuria, severe hypertensive nephrosclerosis, and tubulointerstitial damage. Eplerenone significantly reduced proteinuria (127.4 +/- 26.5 vs. 51.9 +/- 16.7 mg/24 h, p < 0.01), improved glomerular and arteriolar injuries (65 +/- 9 vs. 29 +/- 9 score/100 glomeruli, p < 0.01; 116 +/- 18 vs. 41 +/- 13 score/100 arterioles, p < 0.01, respectively), and decreased tubulointerstitial damage index (1.43 +/- 0.07 vs. 0.39 +/- 0.07, p < 0.01) without altering mean arterial pressure or glomerular dynamics. Combined therapy of eplerenone with lisinopril produced no further benefits than lisinopril alone., Conclusion: The aldosterone antagonist eplerenone significantly ameliorated proteinuria and nephrosclerosis in the L-NAME/SHR model, independent of hemodynamic effects., (Copyright 2004 S. Karger AG, Basel)

Objective: To explore the effect of perindopril on renal interstitial fibrosis of spontaneously hypertensive rats and on the expression of transforming growth factor-beta1., Methods: Spontaneously hypertensive rats at the age of 9 weeks were randomly assigned to 2 groups: Spontaneously hypertensive rats (SHR, vehicle once daily, n = 10) and Treament-SHR (T-SHR, perindopril, 4 mg/(kg x d), per day PO, n = 10). Wistar-Kyoto rats (WKY, n = 7) were served as controls. After 10 weeks of treatment, the serum concentration of TGF-beta1, collagen type I, III and TGF-beta1 in the renal interstitum and renal mRNA levels of TGF-beta1 were detected., Results: There were no significant differences in the serum TGF-beta1 levels among the 3 groups (P > 0.05). Immunohistochemical studies revealed a significant interstitial accumulation of collagens I, III and TGF-beta1 in SHR compared with those in WKY (P < 0.01 or P < 0.05). These changes in SHR were significantly ameliorated by the administration of perindopril (P < 0.01 or P < 0.05). In SHR, renal TGF-beta1 mRNA expression was increased significantly compared with that in WKY (P < 0.01), but perindopril decreased it to the normal levels of WKY (P > 0.05). The increased expression of TGF-beta1 was blocked by perindopril. The expressions of collagens I and III in renal interstitum significantly correlated with the accumulation of TGF-beta1 in the renal (r = 0. 734, r = 0.762, respectively; P < 0.01)., Conclusion: The tubulointerstitial fibrosis of spontaneously hypertensive rats is mediated by an increased level of TGF-beta1 in the renal tissue, and perindopril may decrease the expression of TGF-beta1 to ameliorate the tubulointerstitial fibrosis.

Complete ureteral obstruction in rats rapidly leads to renal interstitial expansion and fibrosis and this process is ameliorated by concomitant angiotensin converting enzyme inhibition (ACEI). However, models of intervention initiated after unilateral ureteral obstruction (UUO) release may be more analogous to human obstructive renal disease where treatment could more reasonably follow the discovery of obstructive uropathy as compared to models where treatment is initiated at the time of experimentally induced obstruction. We studied interstitial changes in rats before and after release of UUO and examined the effect of ACEI with 200mg/L of enalapril (E) in the drinking water on these changes. Rats were sacrificed after 10 (n=10) and 20 (n=10) days (D) of UUO or 10D after release of 10D of UUO (n=18). Eleven rats received E for 10D after UUO release. Cortical interstitial volume fraction [Vv(I/C)] measured by point counting was increased at 10D (0.32 +/- 0.05) and 20D (0.41 +/- 0.05) of UUO compared to contralateral and sham-operated kidneys (both 0.05 +/- 0.01, ANOVA, p <0.001). Vv(I/C) 10D after release from 10D of UUO (0.26 +/- 0.04) was lower than that of 10D of UUO (p<0.05) and much lower than those with 20D of UUO (p<0.001). However, rats treated with E from the time of UUO release had lower Vv(I/C) (0.21 +/- 0.07) than UUO released E untreated rats (p<0.05). Release of UUO initiates regression of interstitial expansion in rats. ACEI with enalapril significantly accelerates reversal of interstitial expansion after UUO release. This could have important implications for treatment of obstructive nephropathy in humans.

Objective: To determine the responses of the new dihydropyridine N- and L-type calcium antagonist, cilnidipine, on systemic and renal hemodynamics, glomerular dynamics, renal function, and histopathology in an Nomega-nitro-l-arginine methylester spontaneously hypertensive rat (l-NAME/SHR) model of nephrosclerosis., Methods: Five groups of 20-week-old male SHR were studied using renal micropuncture techniques and histopathological analyses: group 1, control; group 2, cilnidipine (10 mg/kg per day) by gavage, for 3 weeks; group 3, l-NAME (50 mg/l) in drinking water, for 3 weeks; group 4, combination of l-NAME and cilnidipine, for 3 weeks; group 5, l-NAME for 3 weeks, followed by cilnidipine for a subsequent 3 weeks., Results: Cilnidipine significantly reduced mean arterial pressure, total peripheral resistance and renal vascular resistance, while increasing effective renal blood flow and glomerular filtration rate (P < 0.01) in l-NAME/SHR. These hemodynamic changes were associated with significantly increased single nephron glomerular filtration rate (SNGFR) and plasma flow (SNPF) and decreased afferent glomerular arteriolar resistances when cilnidipine was used alone, and with increased SNGFR and SNPF, but decreased glomerular capillary pressure, afferent and efferent arteriolar resistances, urinary protein excretion, serum creatinine and uric acid concentrations (at least P < 0.05) in l-NAME-exacerbated SHR nephrosclerosis. In addition, glomerular and arteriolar injuries were markedly reversed (both P < 0.01), and glomerular apoptosis and cellular proliferation were inhibited and associated with glomerular tuft enlargement and an increase in cell number., Conclusion: Cilnidipine not only prevented, but reversed, the severe renal hemodynamic and glomerular dynamic changes, including apoptosis and glomerular cellular proliferation, in l-NAME/SHR-exacerbated nephrosclerosis. This dual-channel calcium antagonist thus exerted renoprotective pathophysiological effects in the l-NAME/SHR.

Background/aims: The administration of an angiotensin-converting enzyme (ACE) inhibitor or an oral adsorbent, AST-120 (Kremezin), prevents the progression of renal failure. This study was designed to determine the additional effects of AST-120 combined with an ACE inhibitor, benazepril, on the progression of renal fibrosis in uremic rats., Methods: 5/6-nephrectomized uremic rats were divided into control uremic rats (CRF group), benazepril-treated uremic rats (CRF+B group) and uremic rats receiving benazepril and AST-120 (CRF+BK group). After 14 weeks of treatment renal function and pathological changes were investigated., Results: The progression of renal dysfunction was delayed in both the CRF+B and CRF+BK groups as compared with the CRF group. In the CRF+BK group, the level of serum and urinary indoxyl sulfate and the tubular accumulation of indoxyl sulfate decreased. Both the CRF+B and CRF+BK groups showed lower glomerular sclerosis indices than the CRF group. In the CRF+BK group, but not the CRF+B group, the interstitial fibrosis area and the expression of transforming growth factor (TGF) beta1 and tissue inhibitor of metalloproteinases (TIMP) 1 were decreased as compared with the CRF group. Furthermore, the CRF+BK group showed a smaller interstitial fibrosis area and a lower renal osteopontin expression than the CRF+B group., Conclusion: Combination therapy of benazepril and AST-120 is more effective than benazepril alone in retarding the progression of interstitial fibrosis by reducing the expression of TGF-beta 1, TIMP-1 and osteopontin., (Copyright 2002 S. Karger AG, Basel)

Nephrosclerosis constitutes a major cause of end-stage renal disease. Independently of blood pressure control, ACE inhibitors (ACEIs) are considered to be more nephroprotective than other antihypertensive agents. We have reviewed the long-term evolution of renal function in our series of essential hypertensive patients diagnosed as having nephrosclerosis when first seen in our unit. The analysis was performed depending on whether or not their antihypertensive therapy contained an ACEI alone or in combination for the whole follow-up. The end point was defined as the confirmation of a 50% reduction in creatinine clearance or entry in a dialysis program. A historical cohort of 295 patients was included in the analysis. Mean follow-up was 7.4+/-3.9 years. Diabetes prevalence was higher in ACEI-treated patients (25.7% versus 7.1%, P=0.000), but the diagnosis of diabetic nephropathy could not be confirmed on clinical grounds, including renal biopsy. Twenty-three out of 183 (12.6%) patients in the ACEI group and 23 out of 112 (20.5%) patients in the non-ACEI group experienced a renal event (P=0.0104 by log rank test). Similar results were observed when only nondiabetic patients were considered for the analysis. Cox regression analysis showed that baseline serum creatinine, absence of ACEI administration, mean proteinuria during follow-up, and age were independent predictors for the development of a renal event. In hypertensive nephrosclerosis, therapy containing an ACEI alone or in combination significantly reduces the incidence of renal events. This effect is independent of blood pressure control.

Context: Incidence of end-stage renal disease due to hypertension has increased in recent decades, but the optimal strategy for treatment of hypertension to prevent renal failure is unknown, especially among African Americans., Objective: To compare the effects of an angiotensin-converting enzyme (ACE) inhibitor (ramipril), a dihydropyridine calcium channel blocker (amlodipine), and a beta-blocker (metoprolol) on hypertensive renal disease progression., Design, Setting, and Participants: Interim analysis of a randomized, double-blind, 3 x 2 factorial trial conducted in 1094 African Americans aged 18 to 70 years with hypertensive renal disease (glomerular filtration rate [GFR] of 20-65 mL/min per 1.73 m(2)) enrolled between February 1995 and September 1998. This report compares the ramipril and amlodipine groups following discontinuation of the amlodipine intervention in September 2000., Interventions: Participants were randomly assigned to receive amlodipine, 5 to 10 mg/d (n = 217), ramipril, 2.5 to 10 mg/d (n = 436), or metoprolol, 50 to 200 mg/d (n = 441), with other agents added to achieve 1 of 2 blood pressure goals., Main Outcome Measures: The primary outcome measure was the rate of change in GFR; the main secondary outcome was a composite index of the clinical end points of reduction in GFR of more than 50% or 25 mL/min per 1.73 m(2), end-stage renal disease, or death., Results: Among participants with a urinary protein to creatinine ratio of >0.22 (corresponding approximately to proteinuria of more than 300 mg/d), the ramipril group had a 36% (2.02 [SE, 0.74] mL/min per 1.73 m(2)/y) slower mean decline in GFR over 3 years (P =.006) and a 48% reduced risk of the clinical end points vs the amlodipine group (95% confidence interval [CI], 20%-66%). In the entire cohort, there was no significant difference in mean GFR decline from baseline to 3 years between treatment groups (P =.38). However, compared with the amlodipine group, after adjustment for baseline covariates the ramipril group had a 38% reduced risk of clinical end points (95% CI, 13%-56%), a 36% slower mean decline in GFR after 3 months (P =.002), and less proteinuria (P<.001)., Conclusion: Ramipril, compared with amlodipine, retards renal disease progression in patients with hypertensive renal disease and proteinuria and may offer benefit to patients without proteinuria.

Proteoglycans are an important component of the extracellular matrix, and are thought to play multiple roles not only in kidney remodeling, but also in regulating glomerular permeability, and in modulating the activity of other cytokines and growth factors. The aim of this study was to examine the gene expressions of proteoglycan core proteins in hypertensive rat kidneys, and their modulation by AT1 receptor antagonist. SHRSP/Izm rats and normotensive control WKY/Izm rats on a normal salt diet were treated with or without the AT1 receptor antagonist candesartan cilexetil (1 mg/kg/day) from 10 weeks to 22 weeks. At the end of the treatment period, renal tissue was excised, and gene expressions of the proteoglycan core proteins versican, perlecan, decorin, and biglycan were examined by Northern blot analysis and RT-PCR. Treatment with candesartan cilexetil caused significant decreases in blood pressure and amelioration of proteinuria and renal histological scores in the SHRSP/Izm rats. Compared to WKY/Izm rats, expression of biglycan mRNA showed a small increase in SHRSP/Izm rats which did not attain statistical significance. On the other hand, treatment with candesartan caused significant reductions in biglycan and decorin mRNA in the SHRSP/Izm rats. In contrast, the level of versican mRNA appeared to be increased after candesartan treatment. These results suggest that treatment with AT1 receptor antagonist was associated with diverse changes in renal proteoglycan gene expression in SHRSP/Izm rats. These changes could contribute to the beneficial effects of AT1 receptor antagonist on tissue remodeling and inhibition of disease progression in hypertensive rat kidneys.

Background: We investigated whether monocyte chemoattractant protein-1 (MCP-1) is expressed in hypertensive nephrosclerosis, and tested the effect of angiotensin II type 1 receptor blockade on MCP-1 expression and macrophage (MPhi) infiltration., Methods: Rats with two-kidney, one-clip (2K1C) hypertension with and without treatment with the angiotensin II type 1 receptor antagonist valsartan (3 mg/kg/day) were studied. In these animals as well as in spontaneously hypertensive rats (SHR), stroke-prone SHR (SHR-SP), hypertensive mRen-2 transgenic rats (TGR), and respective control strains, MCP-1 expression in the kidney was investigated by Northern and Western blots and by immunohistochemistry. Glomerular and interstitial MPhis were counted., Results: In the nonclipped kidney of 2K1C rats, MCP-1 expression was elevated at 14 and 28 days when significant MPhi infiltration was present. MCP-1 was localized to glomerular endothelial and epithelial cells, interstitial and tubular cells, MPhis, and vascular smooth muscle cells. A similar pattern of MCP-1 staining was present in TGR kidneys, whereas MCP-1 expression was not increased in SHR and SHR-SP. Valsartan reduced but did not normalize blood pressure, blocked the induction of MCP-1 protein in 2K1C kidneys, and decreased interstitial MPhi infiltration significantly., Conclusion: MCP-1 expression is increased in angiotensin II-dependent models of hypertensive nephrosclerosis and is temporally and spatially related to MPhi infiltration. The angiotensin II type 1 receptor mediates the induction of MCP-1.