Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.23.15 (renin)
 35,795 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study was designed to investigate the relationship between apoptosis and glomerular injury in spontaneously hypertensive rats (SHR) with hypertensive disease that was exacerbated by inhibition of NO synthesis. Development of glomerular cell apoptosis was evaluated by assessment of renal hemodynamics, glomerular morphometric changes, and participation of the renin-angiotensin system. Three groups of 20-week-old SHR were investigated: control male SHR and 2 similar groups given 2 doses of N(G)-nitro-L-arginine methyl ester (L-NAME, 50 or 80 mg/L, respectively) for 3 weeks. Mean arterial pressure and renal vascular resistance increased, whereas effective renal plasma flow and glomerular filtration rate were diminished by L-NAME. The small artery wall/lumen ratio increased as the glomerular-tuft area diminished. Renal cortical tissue levels of angiotensin II increased in response to the L-NAME, thereby inducing afferent arteriolar injury. Apoptosis and proliferative index (PCNA) of nonsclerotic glomeruli were induced by the low-dose L-NAME as the glomerular cell number decreased. In contrast, the PCNA index was downregulated with the high-dose L-NAME. These results indicate that angiotensin II activation, induced by L-NAME, was related to glomerular cell deletion and apoptosis together with the pathophysiological changes of severe nephrosclerosis and impaired renal dynamics.
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PMID:Apoptosis and glomerular injury after prolonged nitric oxide synthase inhibition in spontaneously hypertensive rats. 1175 7

Angiotensin II and insulin-like growth factor-I (IGF-I) are known to be actively involved in the pathogenesis of progressive renal injury, particularly in cell proliferation and phenotypic changes that contribute to tubulointerstitial injury. To investigate the possible mechanisms by which angiotensin II type 1 receptor antagonist (AIIA) ameliorates renal injury in a renal ablation model and to determine the contribution of phenotypic changes and IGF-I to morphological changes, we examined 1) whether AIIA attenuated phenotypic changes as markers of alpha-smooth muscle actin (SMA) and vimentin, 2) whether AIIA altered renal IGF-I expression, and 3) the changes of tubulointerstitial cell kinetics between apoptosis (tested via terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling, TUNEL) and cell proliferation (a test of proliferating cell nuclear antigen, PCNA). Following a sham operation (sham) or 5/6 nephrectomy (Nx), we administered E4177, a potent, selective competitive angiotensin II type 1 receptor antagonist (AIIA), for 10 weeks. In Nx rats, SMA and vimentin expressions developed in injured tubulointerstitium, particularly in hypoperfused scar-adjacent areas, and there was an increase in renal IGF-I expressions. The TUNEL score increased 5-fold and PCNA increased 8-fold, compared with TUNEL and PCNA measurements in sham-operated rats. Renin expression in the juxtaglomerular apparatus was markedly suppressed in the Nx group, although de novo tubular renin expression appeared in Nx, compared with that in the sham group. E4177, both 10 mg/kg (AIIA 10) and 1 mg/kg (AIIA 1), markedly ameliorated renal injury, although blood pressure was less affected in AIIA 1. Both AIIA 10 and AIIA 1 suppressed the neoexpressions of SMA and vimentin in an association with decreased IGF-I expression. Regarding cell kinetics, neither AIIA 10 nor AIIA 1 decreased the TUNEL score; rather, tended to increase, while PCNA was significantly suppressed by AIIA. In conclusion, one of the underlying protective mechanisms of AIIA in this model may be related to the modulations of angiotensin II-induced phenotypic changes and tubulointerstitial cell kinetics through IGF-I.
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PMID:Angiotensin II and IGF-I may interact to regulate tubulointerstitial cell kinetics and phenotypic changes in hypertensive rats. 1204 42

The renin angiotensin system plays an important role in growth and development. Exposure of the neonate to an ACE inhibitor increases mortality and results in growth retardation and abnormal development. We have demonstrated that ACE inhibition in the developing kidney increases apoptosis and decreases cell proliferation, which may account for renal growth impairment. To evaluate the role of endogenous angiotensin in cardiac development, the relationship between ACE inhibition, cell proliferation, apoptosis, several modulators of apoptosis (bcl-2, bcl-xl, and clusterin) was examined in the developing rat heart. Thirty-five newborn rat pups were treated with enalapril (30 mg/kg/d) or a vehicle (control group) for 7 d, and hearts were removed for rt-PCR and Western blotting of bcl-2, bcl-xl, and clusterin. An additional 10 rat pups were treated with hydralazine (10 mg/kg/d) or a vehicle, to serve as a hypotensive control. Cell proliferation was determined by PCNA immunostaining, and apoptosis was detected using the total TUNEL technique. Enalapril treatment resulted in a 24% mortality, reduced body weight, and decreased heart weight (p < 0.05). Enalapril decreased proliferating myocytes by 23%, and reduced proliferating cardiac interstitial cells by 8.1% (p < 0.05). Enalapril also decreased myocytes apoptosis by 60%, but the proportion of myocytes undergoing apoptosis was 10-fold less than that of proliferating cells. Cardiac bcl-2 mRNA, clusterin mRNA, bcl-2 protein, and bcl-xl protein content were not changed, but clusterin protein expression was decreased by enalapril treatment. Hydralazine did not alter cardiac cell proliferation or apoptosis. We conclude that ACE inhibition decreases cell turnover in the developing rat heart, which may contribute to cardiac growth impairment. The loss of myocytes may lead to greater myocyte hypertrophy and myocardial damage during later life.
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PMID:Angiotensin converting enzyme inhibition decreases cell turnover in the neonatal rat heart. 1219 62

The nonobese diabetic mouse is a model of spontaneous insulin-dependent diabetes mellitus. The present study made longitudinal observations of renal lesions in the acute-progressive phase of diabetic mice 0, 10, 20, 30, and 40 days after onset of diabetes without insulin therapy. Plasma creatinine and blood urea nitrogen concentrations gradually increased after onset of diabetes. Kidney weight increased and plateaued at day 20. Under electron microscopy the glomeruli demonstrated only mild changes on day 40. In the proximal tubules proliferating cell nuclear antigen-positive nuclei and nuclear divisions were increased on days 10 and 20. On day 40 of diabetes, increased periodic acid-Schiff-positive granules, confirmed as lysosomal dense bodies, increased neuronal nitric oxide synthase (nNOS) positive reaction, and decreased periodic acid-Schiff staining in the brush border were observed in the proximal straight tubules. In the juxtaglomerular apparatus stratified macula densa were decreased with time in diabetes compared with the findings on day 0, and this macula densa positively reacted with nNOS. No changes in renin levels were observed. In addition, apoptotic cells were not detected. In conclusion, this research represents the first thorough characterization of acute changes in nonobese diabetic mouse kidneys. The results demonstrated renal hypertrophy and slight glomerular injury in early stages and structural alteration of the proximal straight tubules at later stages during the acute phase of diabetes. Furthermore, increased nNOS may represent one of the pathogenic factors of diabetic nephropathy.
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PMID:Renal lesions in spontaneous insulin-dependent diabetes mellitus in the nonobese diabetic mouse: acute phase of diabetes. 1263 59

Angiotensin II, a main effector peptide in the renin-angiotensin system, acts as a growth-promoting and angiogenic factor via type 1 angiotensin II receptors (AT(1)R). We have recently demonstrated that angiotensin II enhanced tumour cell invasion and vascular endothelial growth factor (VEGF) secretion via AT1R in ovarian cancer cell lines in vitro. The aim of the present study was to determine whether AT1R expression in ovarian cancer is correlated with clinicopathological parameters, angiogenic factors and patient survival. Immunohistochemical staining for AT1R, VEGF, CD34 and proliferating cell nuclear antigen (PCNA) were analysed in ovarian cancer tissues (n = 67). Intratumour microvessel density (MVD) was analysed by counting the CD34-positive endothelial cells. Type 1 angiotensin II receptors were expressed in 85% of the cases examined, of which 55% were strongly positive. Type 1 angiotensin II receptors expression was positively correlated with VEGF expression intensity and MVD, but not with histological subtype, grade, FIGO stage or PCNA labelling index. In patients who had positive staining for AT1R, the overall survival and progression-free survival were significantly poor (P = 0.041 and 0.017, respectively) as compared to those in patients who had negative staining for AT1R, although VEGF, but not AT1R, was an independent prognostic factor on multivariate analysis. These results demonstrated that AT1R correlated with tumour angiogenesis and poor patient outcome in ovarian cancer, suggesting its clinical potential for a novel molecular target in strategies for ovarian cancer treatment.
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PMID:Angiotensin II type 1 receptor expression in ovarian cancer and its correlation with tumour angiogenesis and patient survival. 1643 90

Transgenic rats with inducible ANG II-dependent malignant hypertension [TGR(Cyp1a1Ren2)] were generated by inserting the mouse Ren2 renin gene into the genome of the rat. The present study was performed to assess renal morphological changes occurring during the development of ANG II-dependent malignant hypertension in these rats. Male Cyp1a1-Ren2 rats (n = 10) were fed normal rat food containing indole-3-carbinol (I3C; 0.3%) for 10 days to induce malignant hypertension. Rats induced with I3C had higher mean arterial pressures (173 +/- 9 vs. 112 +/- 11 mmHg, P < 0.01) than noninduced normotensive rats (n = 9). Glomerular damage was evaluated by determination of the glomerulosclerosis index (GSI) in tissue sections stained with periodic acid-Schiff. Kidneys of hypertensive rats had a higher GSI than normotensive rats (21.3 +/- 5.6 vs. 3.5 +/- 1.31 units). Quantitative analysis of macrophage ED-1-positive cells and proliferating cell nuclear antigen using immunohistochemistry demonstrated increased macrophage numbers in the renal interstitium (106.4 +/- 11.4 vs. 58.7 +/- 5.0 cells/mm(2)) and increased proliferating cell number in cortical tubules (37.8 +/- 5.7 vs. 24.2 +/- 2.1 cells/mm(2)), renal cortical vessels (2.2 +/- 0.5 vs. 0.13 +/- 0.07 cells/vessel), and the cortical interstitium (33.6 +/- 5.7 vs. 4.2 +/- 1.4 cells/mm(2)) of hypertensive rat kidneys. These findings demonstrate that the renal pathological changes that occur during the development of malignant hypertension in Cyp1a1-Ren2 rats are characterized by inflammation and cellular proliferation in cortical vessels and tubulointerstitium.
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PMID:Renal vascular and tubulointerstitial inflammation and proliferation in Cyp1a1-Ren2 transgenic rats with inducible ANG II-dependent malignant hypertension. 1734 86

Metabolic syndrome (MS) is an independent risk factor for chronic kidney diseases. As the renin-angiotensin system (RAS) is known to have a key role in renal damage, blockade of RAS may show renoprotective effects in MS. In this study, we investigated the renoprotective effects and mechanisms of action of an angiotensin receptor blocker (ARB) in spontaneously hypertensive (SHR/NDmcr-cp) rats as a model of MS. Male SHR/NDmcr-cp rats at 9 weeks of age were divided into three groups, each of which was treated for 12 weeks with vehicle, hydralazine (7.5 mg kg(-1) per day, p.o.) or ARB (olmesartan, 5 mg kg(-1) per day, p.o.). Blood pressure and urinary protein (UP) excretion were monitored. Kidney tissues were subjected to histological, immunohistochemical and molecular analyses. UP excretion increased with age in vehicle-treated SHR/NDmcr-cp rats compared with that in age-matched WKY/Izm rats. In addition, there was significant glomerular damage (increased glomerular sclerosis index, desmin staining and proliferating cell nuclear antigen (PCNA)-positive cells, electron microscopic findings of podocyte injury) and tubulointerstitial damage (increased tubulointerstitial fibrosis index, type IV collagen staining, PCNA-positive cells and expression of TGF-beta mRNA) in vehicle-treated SHR/NDmcr-cp rats compared with that in control rats. All the findings that related to glomerular and tubulointerstitial damage were significantly improved by ARB. Hydralazine mitigated the observed renal damage but was much less effective than ARB, despite similar decreases in blood pressure. There were no significant differences in glucose and lipid metabolism among vehicle-treated, hydralazine-treated and ARB-treated SHR/NDmcr-cp animals. These data suggest that RAS is deeply involved in the pathogenesis of renal damage in MS, and ARBs could provide a powerful renoprotective regimen for patients with MS.
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PMID:Renoprotective effects of an angiotensin II receptor blocker in experimental model rats with hypertension and metabolic disorders. 1966 21

Cardiovascular complications are the leading cause of death in patients with chronic kidney disease (CKD). Traditional causes such as diabetes, smoking, aging and hypertension do not fully explain the high rate of morbidity from cardiovascular disease seen in these patients. The renin-angiotensin-aldosterone system (RAAS) regulates extracellular volume homeostasis, which contributes to blood pressure stability. Overactivity of this system is involved in the pathophysiology of cardio-renal disease. New evidence suggests that vitamin D receptor activators (VDRAs) have a suppressive effect on the RAAS; however, VDRAs also have anti-inflammatory and anti-fibrotic effects. We have demonstrated that paricalcitol, a VDRA, ameliorates left ventricular hypertrophy (LVH) in uremic rats by up-regulating the VDR, decreasing myocardial PCNA and also decreasing myocardial oxidative stress. Thus, paricalcitol can suppress the progression of LVH, myocardial and perivascular fibrosis and myocardial arterial vessel thickness presumably by up-regulating the VDR. Paricalcitol may prove to have a substantial beneficial effect on cardiac disease and its outcome in patients with CKD. Prospective randomized studies in CKD patients are necessary to confirm these results.
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PMID:Myocardial effects of VDR activators in renal failure. 2023 14

Obesity during childhood increases the risk of cardiac disease, hypertension, and other complications in adulthood. We investigated the cellular and renin-angiotensin system changes of the heart in obese young rats. We used Sprague-Dawley rats and early obesity was induced by overfeeding through adjusting the number of male pups per dam during the first 28 days of life. The body weight, heart weight, blood pressure, serum glucose, and blood pressure were assessed and we performed echocardiography, proliferating cell nuclear antigen (PCNA); assessment, apoptosis and Masson's trichrome staining, and Western blotting and the results were compared between the normal litter (NL, control) and the small litter (SL, obesity). There were no differences in blood pressure and serum glucose, but the body weight increased 61.2% and the interventricular septal thickness in diastole on the echocardiography was increased in the SL. There was hyperplasia of the PCNA cells and apoptotic cells without cellular hypertrophy or change of the amount of collagen in the SL. On Western blotting, rennin, and angiotensin II type 2 receptor (AT2R) were increased without a change of angiotensin II type 1 receptor (AT1R) in the SL. Early obesity caused echocardiographically detected septal hypertrophy and an increase of cellular turnover. Renin and AT2R were upregulated without a change of AT1R and the increase of AT2R was regarded as a cardioprotective effect against the pathologic conditions caused by the early obesity.
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PMID:Cellular and RAS changes in the hearts of young obese rats. 2143 6

Adipose tissue influences vascular function through adipocyte-derived factors, including components of the renin-angiotensin-aldosterone system. Molecular mechanisms underlying these phenomena are elusive. We investigated the role of adipocyte-derived factors on mitogen-activated protein kinases (MAPKs), proinflammatory status, apoptosis, and mitogenic signaling in vascular smooth muscle cells (VSMCs) and questioned whether these effects involve mineralocorticoid receptor (MR), glucocorticoid receptor (GR), and angiotensin II type 1 receptor (AT(1)R). Cultured mouse VSMCs were exposed to adipocyte-conditioned medium (ACM) from differentiated 3T3-L1 adipocytes. ACM induced phosphorylation of stress-activated protein kinase/c-Jun N-terminal kinase, p38MAPK, and extracellular signal-regulated kinase 1/2 and increased expression of proinflammatory and proliferative markers in VSMCs. Eplerenone (MR antagonist), mifepristone (GR antagonist), and candesartan (AT(1)R antagonist) inhibited ACM-induced effects on extracellular signal-regulated kinase 1/2, p38MAPK, and proliferating cell nuclear antigen, without influencing apoptosis (Bax, Bcl, and caspase 3). Stress-activated protein kinase/c-Jun N-terminal kinase phosphorylation was inhibited by mifepristone and candesartan but not by eplerenone. ACM-induced increase of fibronectin, vascular cell adhesion molecule 1, and plasminogen activator inhibitor 1 expression was blocked by MR and AT(1)R antagonism but not by GR inhibition. ACM has no effect on GR, MR, and AT(1)R expression. Our data show that adipocyte-derived factors influence MAPK signaling, leading to VSMC proinflammatory and profibrotic responses through distinct pathways. Although ACM stimulates p38MAPK and extracellular signal-regulated kinase 1/2 phosphorylation through MR, GR, and AT(1)R, activation of stress-activated protein kinase/c-Jun N-terminal kinase involves GR and AT(1)R. These findings suggest that adipocyte-derived factors regulate VSMC function through specific MAPKs linked to MR, GR, and AT(1)R, a posttranslational phenomenon, because ACM did not influence receptor expression. Such cross-talk between adipocytes and VSMCs may provide a potential molecular mechanism linking renin-angiotensin-aldosterone system, adipocytes, and vascular function.
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PMID:Adipocyte-derived factors regulate vascular smooth muscle cells through mineralocorticoid and glucocorticoid receptors. 2178 4


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