scholarly journals Renal protection in chronic kidney disease: hypoxia-inducible factor activation vs. angiotensin II blockade

2010 ◽  
Vol 299 (6) ◽  
pp. F1365-F1373 ◽  
Author(s):  
Aihua Deng ◽  
Mary Ann K. Arndt ◽  
Joseph Satriano ◽  
Prabhleen Singh ◽  
Timo Rieg ◽  
...  

The 5/6thnephrectomy or ablation/infarction (A/I) preparation has been used as a classic model of chronic kidney disease (CKD). We observed increased kidney oxygen consumption (QO2) and altered renal hemodynamics in the A/I kidney that were normalized after combined angiotensin II (ANG II) blockade. Studies suggest hypoxia inducible factor as a protective influence in A/I. We induced hypoxia-inducible factor (HIF) and HIF target proteins by two different methods, cobalt chloride (CoCl2) and dimethyloxalyglycine (DMOG), for the first week after creation of A/I and compared the metabolic and renal hemodynamic outcomes to combined ANG II blockade. We also examined the HIF target proteins expressed by using Western blots and real-time PCR. Treatment with DMOG, CoCl2, and ANG II blockade normalized kidney oxygen consumption factored by Na reabsorption and increased both renal blood flow and glomerular filtration rate. At 1 wk, CoCl2and DMOG increased kidney expression of HIF by Western blot. In the untreated A/I kidney, VEGF, heme oxygenase-1, and GLUT1 were all modestly increased. Both ANG II blockade and CoCl2therapy increased VEGF and GLUT1 but the cobalt markedly so. ANG II blockade decreased heme oxygenase-1 expression while CoCl2increased it. By real-time PCR, erythropoietin and GLUT1 were only increased by CoCl2therapy. Cell proliferation was modestly increased by ANG II blockade but markedly after cobalt therapy. Metabolic and hemodynamic abnormalities were corrected equally by ANG II blockade and HIF therapies. However, the molecular patterns differed significantly between ANG II blockade and cobalt therapy. HIF induction may prove to be protective in this model of CKD.

2016 ◽  
Vol 310 (6) ◽  
pp. F466-F476 ◽  
Author(s):  
Lu Kang ◽  
Joseph P. Grande ◽  
Matthew L. Hillestad ◽  
Anthony J. Croatt ◽  
Michael A. Barry ◽  
...  

The arteriovenous fistula (AVF) is the preferred hemodialysis vascular access, but it is complicated by high failure rates and attendant morbidity. This study provides the first description of a murine AVF model that recapitulates two salient features of hemodialysis AVFs, namely, anastomosis of end-vein to side-artery to create the AVF and the presence of chronic kidney disease (CKD). CKD reduced AVF blood flow, observed as early as 3 days after AVF creation, and increased neointimal hyperplasia, venous wall thickness, thrombus formation, and vasculopathic gene expression in the AVF. These adverse effects of CKD could not be ascribed to preexisting alterations in blood pressure or vascular reactivity in this CKD model. In addition to vasculopathic genes, CKD induced potentially vasoprotective genes in the AVF such as heme oxygenase-1 (HO-1) and HO-2. To determine whether prior HO-1 upregulation may protect in this model, we upregulated HO-1 by adeno-associated viral gene delivery, achieving marked venous induction of the HO-1 protein and HO activity. Such HO-1 upregulation improved AVF blood flow and decreased venous wall thickness in the AVF. Finally, we demonstrate that the administration of carbon monoxide, a product of HO, acutely increased AVF blood flow. This study thus demonstrates: 1) the feasibility of a clinically relevant murine AVF model created in the presence of CKD and involving an end-vein to side-artery anastomosis; 2) the exacerbatory effect of CKD on clinically relevant features of this model; and 3) the beneficial effects in this model conferred by HO-1 upregulation by adeno-associated viral gene delivery.


2019 ◽  
Vol 9 (11) ◽  
pp. 1614-1620
Author(s):  
Jiangrong Fan ◽  
Yong Zheng ◽  
Jingyang You

BMSCs play a role in osteoporosis (OP) and their differentiation can lead to OP progression. Heme oxygenase-1 (HO-1) involves in many diseases, but the effect of HO-1 on osteoblast differentiation of BMSCs in OP rats remains unclear. SD rats were divided into control group and OP group. Rats BMSCs in OP group were cultured in vitro, HO-1 expression was up-regulated by HO-1 agonist hemin, and BMPR inhibitor LDN-19318 was added followed by analysis of HO-1 expression by real time PCR and ELISA, cell proliferation by MTT assay, apoptosis by Caspase 3 activity, BMP-2 expression by Western blot, ALP activity, expression of Runx2 and OC by real time PCR. In OP group, HO-1 expression was significantly decreased, cell proliferation was inhibited, Caspase 3 activity was increased along with decreased ALP activity and expression of Runx2, OC and BMP-2 compared to control (P < 0.05). Up-regulation of HO-1 expression significantly promoted cell proliferation, reduced Caspase 3 activity, increased ALP activity, and expression of Runx2, OC and BMP-2 (P < 0.05). However, inhibition of HO-1 significantly promoted bone differentiation after the addition of BMPR inhibitor LDN-193189 (P < 0.05). HO-1 expression is decreased in BMSCs of OP group rats. Up-regulation of HO-1 promoted BMSCs proliferation in OP rats in BMP-dependent manner, inhibited apoptosis, and promoted osteoblast differentiation.


2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Eva Csongradi ◽  
Megan V. Storm ◽  
David E. Stec

The goal of this study was to test the hypothesis that renal medullary heme oxygenase (HO) acts as a buffer against Ang-II dependent hypertension. To test this hypothesis, renal medullary HO activity was blocked using QC-13, an imidazole-dioxolane HO-1 inhibitor, or SnMP, a classical porphyrin based HO inhibitor. HO inhibitors were infused via IRMI catheters throughout the study starting 3 days prior to implantation of an osmotic minipump which delivered Ang II or saline vehicle. MAP was increased by Ang II infusion and further increased by IRMI infusion of QC-13 or SnMP. MAP averaged113±3,120±7,141±2,153±2, and154±3 mmHg in vehicle, vehicle + IRMI QC-13, Ang II, Ang II + IRMI QC-13, and Ang II + IRMI SnMP treated mice, respectively (n=6). Inhibition of renal medullary HO activity with QC-13 in Ang II infused mice was also associated with a significant increase in superoxide production as well as significant decreases in antioxidant enzymes catalase and MnSOD. These results demonstrate that renal inhibition of HO exacerbates Ang II dependent hypertension through a mechanism which is associated with increases in superoxide production and decreases in antioxidant enzymes.


2003 ◽  
Vol 228 (5) ◽  
pp. 576-583 ◽  
Author(s):  
Francesco Mazza ◽  
Alvin Goodman ◽  
Gabriella Lombardo ◽  
Angelo Vanella ◽  
Nader G. Abraham

Heme oxygenase (HO) catalyzes the conversion of heme to biliverdin with the release of iron and carbon monoxide. HO-1 is inducible by inflammatory conditions, which cause oxidative stress in endothelial cells. Overexpression of human HO-1 in endothelial cells may have the potential to provide protection against a variety of agents that cause oxidative stress. We investigated the physiological significance of human HO-1 overexpression using a retroviral vector on attenuation of angiotensin II (Ang II)-mediated oxidative stress. Comet and glutathione (GSH) levels were used as indicators of the levels of oxidative stress. Comet assay was performed to evaluate damage on DNA, whereas GSH levels were measured to determine the unbalance of redox potential. Pretreatments with inducers, such as heme 10 μM, SnCl2 10 μM, and inhibitors, such as tin-mesoporphyrin 10 μM was followed by treatment with Ang II 200 ng/ml. Pretreatment with heme or SnCl2 provoked significant reductions ( P < 0.01) of tail moment in the comet assay. Opposite effects were evident by pretreatment for 16 hr with tin-mesoporphyrin. A decrease in tail moment levels was found in human endothelial cells transduced with the human HO-1 gene. The addition of Ang II (200 ng/ml) to human dermal microvessel endothelial cel1-1 for 16 hr resulted in a significant ( P < 0.05) reduction of GSH contents control endothelial cells but not in endothelial cells transduced with HO-1 gene. The results presented indicated that stimulation or overexpression of HO-1 attenuated DNA damages caused by exposures of Ang II.


2019 ◽  
Vol 20 (13) ◽  
pp. 3157 ◽  
Author(s):  
Chih-Chung Lin ◽  
Li-Der Hsiao ◽  
Rou-Ling Cho ◽  
Chuen-Mao Yang

The up-regulation of heme oxygenase-1 (HO-1) is mediated through nicotinamaide adenine dinucleotide phosphate (NADPH) oxidases (Nox) and reactive oxygen species (ROS) generation, which could provide cytoprotection against inflammation. However, the molecular mechanisms of carbon monoxide-releasing molecule (CORM)-2-induced HO-1 expression in human tracheal smooth muscle cells (HTSMCs) remain unknown. Here, we found that pretreatment with CORM-2 attenuated the lipopolysaccharide (LPS)-induced intercellular adhesion molecule (ICAM-1) expression and leukocyte count through the up-regulation of HO-1 in mice, which was revealed by immunohistochemistrical staining, Western blot, real-time PCR, and cell count. The inhibitory effects of HO-1 by CORM-2 were reversed by transfection with HO-1 siRNA. Next, Western blot, real-time PCR, and promoter activity assay were performed to examine the HO-1 induction in HTSMCs. We found that CORM-2 induced HO-1 expression via the activation of protein kinase C (PKC)α and proline-rich tyrosine kinase (Pyk2), which was mediated through Nox-derived ROS generation using pharmacological inhibitors or small interfering ribonucleic acids (siRNAs). CORM-2-induced HO-1 expression was mediated through Nox-(1, 2, 4) or p47phox, which was confirmed by transfection with their own siRNAs. The Nox-derived ROS signals promoted the activities of extracellular signal-regulated kinase 1/2 (ERK1/2). Subsequently, c-Fos and c-Jun—activator protein-1 (AP-1) subunits—were up-regulated by activated ERK1/2, which turned on transcription of the HO-1 gene by regulating the HO-1 promoter. These results suggested that in HTSMCs, CORM-2 activates PKCα/Pyk2-dependent Nox/ROS/ERK1/2/AP-1, leading to HO-1 up-regulation, which suppresses the lipopolysaccharide (LPS)-induced airway inflammation.


2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Chen Sheng-Long ◽  
Wu Yan-Xin ◽  
Huang Yi-Yi ◽  
Fang Ming ◽  
He Jian-Gui ◽  
...  

The nonpeptide AVE0991 is an agonist of the angiotensin-(1–7) (Ang-(1–7)) Mas receptor and is expected to be a putative new drug for treatment of cardiovascular disease. However, the mechanisms involved in the antiproliferative effects of AVE0991 are not fully understood. We saw that the compound attenuated proliferation in an angiotensin II-induced rat vascular smooth muscle cells (VSMC) proliferation model. Moreover, treatment with AVE0991 (10−5 mol/L or10−7 mol/L) significantly attenuated reactive oxygen species (ROS) production, phosphorylation of p38 MAPK, and dose-dependently (10−8to10−5 mol/L) inhibited Ang II-induced VSMC proliferation. Meanwhile, heme oxygenase-1 (HO-1) expression increased in the AVE0991 + Ang II group (10−5 mol/L or10−6 mol/L). However, the beneficial effects of AVE0991 were completely abolished when the VSMC were pretreated with A-779 (10−6 mol/L). Furthermore, treatment with the HO-1 inhibitor ZnPPIX attenuated the inhibitory effect of AVE0991 on Ang II-induced p38MAPK phosphorylation. These results suggest that AVE0991 attenuates Ang II-induced VSMC proliferation in a dose-dependent fashion and that this effect is associated with the Mas/HO-1/p38 MAPK signaling pathway.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Yi Wang ◽  
Hongjuan Liao ◽  
Yueheng Wang ◽  
Jinlin Zhou ◽  
Feng Wang ◽  
...  

Abstract Background Cardiovascular diseases have become the leading cause of death worldwide, and cardiac hypertrophy is the core mechanism underlying cardiac defect and heart failure. However, the underlying mechanisms of cardiac hypertrophy are not fully understood. Here we investigated the roles of Kallikrein 11 (KLK11) in cardiac hypertrophy. Methods Human and mouse hypertrophic heart tissues were used to determine the expression of KLK11 with quantitative real-time PCR and western blot. Mouse cardiac hypertrophy was induced by transverse aortic constriction (TAC), and cardiomyocyte hypertrophy was induced by angiotensin II. Cardiac function was analyzed by echocardiography. The signaling pathway was analyzed by western blot. Protein synthesis was monitored by the incorporation of [3H]-leucine. Gene expression was analyzed by quantitative real-time PCR. Results The mRNA and protein levels of KLK11 were upregulated in human hypertrophic hearts. We also induced cardiac hypertrophy in mice and observed the upregulation of KLK11 in hypertrophic hearts. Our in vitro experiments demonstrated that KLK11 overexpression promoted whereas KLK11 knockdown repressed cardiomyocytes hypertrophy induced by angiotensin II, as evidenced by cardiomyocyte size and the expression of hypertrophy-related fetal genes. Besides, we knocked down KLK11 expression in mouse hearts with adeno-associated virus 9. Knockdown of KLK11 in mouse hearts inhibited TAC-induced decline in fraction shortening and ejection fraction, reduced the increase in heart weight, cardiomyocyte size, and expression of hypertrophic fetal genes. We also observed that KLK11 promoted protein synthesis, the key feature of cardiomyocyte hypertrophy, by regulating the pivotal machines S6K1 and 4EBP1. Mechanism study demonstrated that KLK11 promoted the activation of AKT-mTOR signaling to promote S6K1 and 4EBP1 pathway and protein synthesis. Repression of mTOR with rapamycin blocked the effects of KLK11 on S6K1 and 4EBP1 as well as protein synthesis. Besides, rapamycin treatment blocked the roles of KLK11 in the regulation of cardiomyocyte hypertrophy. Conclusions Our findings demonstrated that KLK11 promoted cardiomyocyte hypertrophy by activating AKT-mTOR signaling to promote protein synthesis.


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