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Jia H, Brixius B, Bocianoski C, Ray S, Koes DR, Brixius-Anderko S. Deciphering the Role of Fatty Acid-Metabolizing CYP4F11 in Lung Cancer and Its Potential As a Drug Target. Drug Metab Dispos 2024; 52:69-79. [PMID: 37973374 DOI: 10.1124/dmd.123.001463] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/25/2023] [Accepted: 11/14/2023] [Indexed: 11/19/2023] Open
Abstract
Lung cancer is the leading cause of cancer deaths worldwide. We found that the cytochrome P450 isoform CYP4F11 is significantly overexpressed in patients with lung squamous cell carcinoma. CYP4F11 is a fatty acid ω-hydroxylase and catalyzes the production of the lipid mediator 20-hydroxyeicosatetraenoic acid (20-HETE) from arachidonic acid. 20-HETE promotes cell proliferation and migration in cancer. Inhibition of 20-HETE-generating cytochrome P450 enzymes has been implicated as novel cancer therapy for more than a decade. However, the exact role of CYP4F11 and its potential as drug target for lung cancer therapy has not been established yet. Thus, we performed a transient knockdown of CYP4F11 in the lung cancer cell line NCI-H460. Knockdown of CYP4F11 significantly inhibits lung cancer cell proliferation and migration while the 20-HETE production is significantly reduced. For biochemical characterization of CYP4F11-inhibitor interactions, we generated recombinant human CYP4F11. Spectroscopic ligand binding assays were conducted to evaluate CYP4F11 binding to the unselective CYP4A/F inhibitor HET0016. HET0016 shows high affinity to recombinant CYP4F11 and inhibits CYP4F11-mediated 20-HETE production in vitro with a nanomolar IC 50 Cross evaluation of HET0016 in NCI-H460 cells shows that lung cancer cell proliferation is significantly reduced together with 20-HETE production. However, HET0016 also displays antiproliferative effects that are not 20-HETE mediated. Future studies aim to establish the role of CYP4F11 in lung cancer and the underlying mechanism and investigate the potential of CYP4F11 as a therapeutic target for lung cancer. SIGNIFICANCE STATEMENT: Lung cancer is a deadly cancer with limited treatment options. Cytochrome P450 4F11 (CYP4F11) is significantly upregulated in lung squamous cell carcinoma. Knockdown of CYP4F11 in a lung cancer cell line significantly attenuates cell proliferation and migration with reduced production of the lipid mediator 20-hydroxyeicosatetraenoic acid (20-HETE). Studies with the unselective inhibitor HET0016 show a high inhibitory potency of CYP4F11-mediated 20-HETE production using recombinant enzyme. Overall, our studies demonstrate the potential of targeting CYP4F11 for new transformative lung cancer treatment.
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Affiliation(s)
- Huiting Jia
- Department of Pharmaceutical Sciences, Center for Pharmacogenetics, University of Pittsburgh School of Pharmacy, Pittsburgh, Pennsylvania (H.J., B.B., S.R., S.B.-A.); Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania (D.R.K.); and Elizabeth Forward High School, Elizabeth, Pennsylvania (C.B.)
| | - Bjoern Brixius
- Department of Pharmaceutical Sciences, Center for Pharmacogenetics, University of Pittsburgh School of Pharmacy, Pittsburgh, Pennsylvania (H.J., B.B., S.R., S.B.-A.); Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania (D.R.K.); and Elizabeth Forward High School, Elizabeth, Pennsylvania (C.B.)
| | - Caleb Bocianoski
- Department of Pharmaceutical Sciences, Center for Pharmacogenetics, University of Pittsburgh School of Pharmacy, Pittsburgh, Pennsylvania (H.J., B.B., S.R., S.B.-A.); Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania (D.R.K.); and Elizabeth Forward High School, Elizabeth, Pennsylvania (C.B.)
| | - Sutapa Ray
- Department of Pharmaceutical Sciences, Center for Pharmacogenetics, University of Pittsburgh School of Pharmacy, Pittsburgh, Pennsylvania (H.J., B.B., S.R., S.B.-A.); Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania (D.R.K.); and Elizabeth Forward High School, Elizabeth, Pennsylvania (C.B.)
| | - David R Koes
- Department of Pharmaceutical Sciences, Center for Pharmacogenetics, University of Pittsburgh School of Pharmacy, Pittsburgh, Pennsylvania (H.J., B.B., S.R., S.B.-A.); Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania (D.R.K.); and Elizabeth Forward High School, Elizabeth, Pennsylvania (C.B.)
| | - Simone Brixius-Anderko
- Department of Pharmaceutical Sciences, Center for Pharmacogenetics, University of Pittsburgh School of Pharmacy, Pittsburgh, Pennsylvania (H.J., B.B., S.R., S.B.-A.); Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania (D.R.K.); and Elizabeth Forward High School, Elizabeth, Pennsylvania (C.B.)
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Liu R, Staruschenko A. Matrix Metalloproteinase 2 Is Crucial for Hypertension- and Hyperglycemia-Induced Kidney Injury Independent of Blood Pressure. J Cardiovasc Pharmacol 2023; 82:438-439. [PMID: 37773888 PMCID: PMC10841042 DOI: 10.1097/fjc.0000000000001488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/01/2023]
Affiliation(s)
- Ruisheng Liu
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL; and
- Hypertension and Kidney Research Center, Morsani College of Medicine, University of South Florida, Tampa, FL
| | - Alexander Staruschenko
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL; and
- Hypertension and Kidney Research Center, Morsani College of Medicine, University of South Florida, Tampa, FL
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Hirata T, Fan F, Fan L, Amin G, White T, Geurts AM, Kojima N, Takahashi T, Miyata N, Williams J, Roman RJ. Knockout of Matrix Metalloproteinase 2 Opposes Hypertension- and Diabetes-induced Nephropathy. J Cardiovasc Pharmacol 2023; 82:445-457. [PMID: 37643020 PMCID: PMC10691661 DOI: 10.1097/fjc.0000000000001473] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 08/07/2023] [Indexed: 08/31/2023]
Abstract
ABSTRACT The progression of chronic kidney disease results from the accumulation of extracellular matrix leading to end-stage renal disease. We previously demonstrated that a broad-spectrum matrix metalloproteinase (MMP) inhibitor reduced renal injury in rat models of hypertension and diabetes. However, the isoforms and mechanisms involved are unclear. This study examined the role of MMP2 during the development of proteinuria and renal injury after induction of hypertension or diabetes in Dahl salt-sensitive (SS) and MMP2 knockout (KO) rats. Mean arterial pressure rose from 115 ± 2 to 145 ± 2 mm Hg and 116 ± 1 to 152 ± 3 mm Hg in MMP2 KO and SS rats fed a high-salt (8% NaCl) diet for 3 weeks. The degree of proteinuria, glomerular injury, renal fibrosis, and podocyte loss was lower in MMP2 KO rats than in SS rats. Blood glucose and HbA1c levels, and mean arterial pressure rose to the same extent in streptozotocin-treated SS and MMP2 KO rats. However, the degree of proteinuria, glomerulosclerosis, renal fibrosis, renal hypertrophy, glomerular permeability to albumin, and the renal expression of MMP2 and TGFβ1 were significantly reduced in MMP2 KO rats. Glomerular filtration rate fell by 33% after 12 weeks of diabetes in streptozotocin-treated SS rats compared with time-control rats, but glomerular filtration rate only fell by 12% in MMP2 KO rats. These results indicate that activation of MMP2 plays an essential role in the pathogenesis of hypertensive and diabetic nephropathy and suggests that an MMP2 inhibitor might slow the progression of chronic kidney disease.
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Affiliation(s)
- Takashi Hirata
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS
- Pharmacology Laboratories, Taisho Pharmaceutical Co., Ltd, Saitama, Japan
| | - Fan Fan
- Department of Physiology, Augusta University, Augusta, GA
| | - Letao Fan
- Research Headquarters of Pharmaceutical Operation, Taisho Pharmaceutical Co., Ltd, Saitama, Japan
| | - Ghadir Amin
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS
| | | | - Aron M Geurts
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI
| | - Naoki Kojima
- Pharmacology Laboratories, Taisho Pharmaceutical Co., Ltd, Saitama, Japan
| | - Teisuke Takahashi
- Pharmacology Laboratories, Taisho Pharmaceutical Co., Ltd, Saitama, Japan
| | - Noriyuki Miyata
- Research Headquarters of Pharmaceutical Operation, Taisho Pharmaceutical Co., Ltd, Saitama, Japan
| | - Jan Williams
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS
| | - Richard J Roman
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS
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Zhang Y, Liu Y, Sun J, Zhang W, Guo Z, Ma Q. Arachidonic acid metabolism in health and disease. MedComm (Beijing) 2023; 4:e363. [PMID: 37746665 PMCID: PMC10511835 DOI: 10.1002/mco2.363] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Revised: 08/13/2023] [Accepted: 08/17/2023] [Indexed: 09/26/2023] Open
Abstract
Arachidonic acid (AA), an n-6 essential fatty acid, is a major component of mammalian cells and can be released by phospholipase A2. Accumulating evidence indicates that AA plays essential biochemical roles, as it is the direct precursor of bioactive lipid metabolites of eicosanoids such as prostaglandins, leukotrienes, and epoxyeicosatrienoic acid obtained from three distinct enzymatic metabolic pathways: the cyclooxygenase pathway, lipoxygenase pathway, and cytochrome P450 pathway. AA metabolism is involved not only in cell differentiation, tissue development, and organ function but also in the progression of diseases, such as hepatic fibrosis, neurodegeneration, obesity, diabetes, and cancers. These eicosanoids are generally considered proinflammatory molecules, as they can trigger oxidative stress and stimulate the immune response. Therefore, interventions in AA metabolic pathways are effective ways to manage inflammatory-related diseases in the clinic. Currently, inhibitors targeting enzymes related to AA metabolic pathways are an important area of drug discovery. Moreover, many advances have also been made in clinical studies of AA metabolic inhibitors in combination with chemotherapy and immunotherapy. Herein, we review the discovery of AA and focus on AA metabolism in relation to health and diseases. Furthermore, inhibitors targeting AA metabolism are summarized, and potential clinical applications are discussed.
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Affiliation(s)
- Yiran Zhang
- Department of Orthopedic SurgeryOrthopedic Oncology InstituteThe Second Affiliated Hospital of Air Force Medical UniversityXi'anChina
| | - Yingxiang Liu
- Department of Orthopedic SurgeryOrthopedic Oncology InstituteThe Second Affiliated Hospital of Air Force Medical UniversityXi'anChina
| | - Jin Sun
- Department of Orthopedic SurgeryOrthopedic Oncology InstituteThe Second Affiliated Hospital of Air Force Medical UniversityXi'anChina
| | - Wei Zhang
- Department of PathologyThe Second Affiliated Hospital of Air Force Medical UniversityXi'anChina
| | - Zheng Guo
- Department of Orthopedic SurgeryOrthopedic Oncology InstituteThe Second Affiliated Hospital of Air Force Medical UniversityXi'anChina
| | - Qiong Ma
- Department of Orthopedic SurgeryOrthopedic Oncology InstituteThe Second Affiliated Hospital of Air Force Medical UniversityXi'anChina
- Department of PathologyThe Second Affiliated Hospital of Air Force Medical UniversityXi'anChina
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Davis MJ, Earley S, Li YS, Chien S. Vascular mechanotransduction. Physiol Rev 2023; 103:1247-1421. [PMID: 36603156 PMCID: PMC9942936 DOI: 10.1152/physrev.00053.2021] [Citation(s) in RCA: 45] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 09/26/2022] [Accepted: 10/04/2022] [Indexed: 01/07/2023] Open
Abstract
This review aims to survey the current state of mechanotransduction in vascular smooth muscle cells (VSMCs) and endothelial cells (ECs), including their sensing of mechanical stimuli and transduction of mechanical signals that result in the acute functional modulation and longer-term transcriptomic and epigenetic regulation of blood vessels. The mechanosensors discussed include ion channels, plasma membrane-associated structures and receptors, and junction proteins. The mechanosignaling pathways presented include the cytoskeleton, integrins, extracellular matrix, and intracellular signaling molecules. These are followed by discussions on mechanical regulation of transcriptome and epigenetics, relevance of mechanotransduction to health and disease, and interactions between VSMCs and ECs. Throughout this review, we offer suggestions for specific topics that require further understanding. In the closing section on conclusions and perspectives, we summarize what is known and point out the need to treat the vasculature as a system, including not only VSMCs and ECs but also the extracellular matrix and other types of cells such as resident macrophages and pericytes, so that we can fully understand the physiology and pathophysiology of the blood vessel as a whole, thus enhancing the comprehension, diagnosis, treatment, and prevention of vascular diseases.
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Affiliation(s)
- Michael J Davis
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri
| | - Scott Earley
- Department of Pharmacology, University of Nevada, Reno, Nevada
| | - Yi-Shuan Li
- Department of Bioengineering, University of California, San Diego, California
- Institute of Engineering in Medicine, University of California, San Diego, California
| | - Shu Chien
- Department of Bioengineering, University of California, San Diego, California
- Institute of Engineering in Medicine, University of California, San Diego, California
- Department of Medicine, University of California, San Diego, California
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Chivers JM, Whiles SA, Miles CB, Biederman BE, Ellison MF, Lovingood CW, Wright MH, Hoover DB, Raafey MA, Youngberg GA, Venkatachalam MA, Zheleznova NN, Yang C, Liu P, Kriegel AJ, Cowley AW, O'Connor PM, Picken MM, Polichnowski AJ. Brown-Norway chromosome 1 mitigates the upregulation of proinflammatory pathways in mTAL cells and subsequent age-related CKD in Dahl SS/JrHsdMcwi rats. Am J Physiol Renal Physiol 2023; 324:F193-F210. [PMID: 36475869 PMCID: PMC9886360 DOI: 10.1152/ajprenal.00145.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 11/23/2022] [Accepted: 11/25/2022] [Indexed: 12/13/2022] Open
Abstract
Chronic kidney disease (CKD) has a strong genetic component; however, the underlying pathways are not well understood. Dahl salt-sensitive (SS)/Jr rats spontaneously develop CKD with age and are used to investigate the genetic determinants of CKD. However, there are currently several genetically diverse Dahl SS rats maintained at various institutions and the extent to which some exhibit age-related CKD is unclear. We assessed glomerulosclerosis (GS) and tubulointerstitial fibrosis (TIF) in 3- and 6-mo-old male and female SS/JrHsdMcwi, BN/NHsd/Mcwi [Brown-Norway (BN)], and consomic SS-Chr 1BN/Mcwi (SS.BN1) rats, in which chromosome 1 from the BN rat was introgressed into the genome of the SS/JrHsdMcwi rat. Rats were fed a 0.4% NaCl diet. GS (31 ± 3% vs. 7 ± 1%) and TIF (2.3 ± 0.2 vs. 0.5 ± 0.1) were significantly greater in 6-mo-old compared with 3-mo-old SS/JrHsdMcwi rats, and CKD was exacerbated in males. GS was minimal in 6- and 3-mo-old BN (3.9 ± 0.6% vs. 1.2 ± 0.4%) and SS.BN1 (2.4 ± 0.5% vs. 1.0 ± 0.3%) rats, and neither exhibited TIF. In SS/JrHsdMcwi and SS.BN1 rats, mean arterial blood pressure was significantly greater in 6-mo-old compared with 3-mo-old SS/JrHsdMcwi (162 ± 4 vs. 131 ± 2 mmHg) but not SS.BN1 (115 ± 2 vs. 116 ± 1 mmHg) rats. In 6-mo-old SS/JrHsdMcwi rats, blood pressure was significantly greater in females. RNA-sequencing analysis revealed that inflammatory pathways were upregulated in isolated medullary thick ascending tubules in 7-wk-old SS/JrHsdMcwi rats, before the development of tubule pathology, compared with SS.BN1 rats. In summary, SS/JrHsdMcwi rats exhibit robust age-related progression of medullary thick ascending limb abnormalities, CKD, and hypertension, and gene(s) on chromosome 1 have a major pathogenic role in such changes.NEW & NOTEWORTHY This study shows that the robust age-related progression of kidney disease in Dahl SS/JrHsdMcw rats maintained on a normal-salt diet is abolished in consomic SS.BN1 rats. Evidence that medullary thick ascending limb segments of SS/JrHsdMcw rats are structurally abnormal and enriched in proinflammatory pathways before the development of protein casts provides new insights into the pathogenesis of kidney disease in this model.
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Affiliation(s)
- Jacqueline M Chivers
- Department of Biomedical Sciences, East Tennessee State University, Johnson City, Tennessee
| | - Shannon A Whiles
- Department of Biomedical Sciences, East Tennessee State University, Johnson City, Tennessee
| | - Conor B Miles
- Department of Biomedical Sciences, East Tennessee State University, Johnson City, Tennessee
| | - Brianna E Biederman
- Department of Biomedical Sciences, East Tennessee State University, Johnson City, Tennessee
| | - Megan F Ellison
- Department of Biomedical Sciences, East Tennessee State University, Johnson City, Tennessee
| | - Connor W Lovingood
- Department of Biomedical Sciences, East Tennessee State University, Johnson City, Tennessee
| | - Marie H Wright
- Department of Biomedical Sciences, East Tennessee State University, Johnson City, Tennessee
| | - Donald B Hoover
- Department of Biomedical Sciences, East Tennessee State University, Johnson City, Tennessee
- Center of Excellence in Inflammation, Infectious Disease and Immunity, East Tennessee State University, Johnson City, Tennessee
| | - Muhammad A Raafey
- Department of Pathology, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee
| | - George A Youngberg
- Department of Pathology, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee
| | | | | | - Chun Yang
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Pengyuan Liu
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Alison J Kriegel
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Allen W Cowley
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Paul M O'Connor
- Department of Physiology, Augusta University, Augusta, Georgia
| | - Maria M Picken
- Department of Pathology, Loyola University Medical Center, Maywood, Illinois
| | - Aaron J Polichnowski
- Department of Biomedical Sciences, East Tennessee State University, Johnson City, Tennessee
- Center of Excellence in Inflammation, Infectious Disease and Immunity, East Tennessee State University, Johnson City, Tennessee
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Williams JM, Murphy SR, Wu W, Border JJ, Fan F, Roman RJ. Renoprotective effects of empagliflozin in type 1 and type 2 models of diabetic nephropathy superimposed with hypertension. GeroScience 2022; 44:2845-2861. [PMID: 35767209 PMCID: PMC9768063 DOI: 10.1007/s11357-022-00610-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 06/15/2022] [Indexed: 01/07/2023] Open
Abstract
Diabetes, hypertension, and aging are major contributors to cardiovascular and chronic kidney disease (CKD). Sodium/glucose cotransporter 2 (SGLT2) inhibitors have become a preferred treatment for type II diabetic patients since they have cardiorenal protective effects. However, most elderly diabetic patients also have hypertension, and the effects of SGLT2 inhibitors have not been studied in hypertensive diabetic patients or animal models. The present study examined if controlling hyperglycemia with empagliflozin, or given in combination with lisinopril, slows the progression of renal injury in hypertensive diabetic rats. Studies were performed using hypertensive streptozotocin-induced type 1 diabetic Dahl salt-sensitive (STZ-SS) rats and in deoxycorticosterone-salt hypertensive type 2 diabetic nephropathy (T2DN) rats. Administration of empagliflozin alone or in combination with lisinopril reduced blood glucose, proteinuria, glomerular injury, and renal fibrosis in STZ-SS rats without altering renal blood flow (RBF) or glomerular filtration rate (GFR). Blood pressure and renal hypertrophy were also reduced in rats treated with empagliflozin and lisinopril. Administration of empagliflozin alone or in combination with lisinopril lowered blood glucose, glomerulosclerosis, and renal fibrosis but had no effect on blood pressure, kidney weight, or proteinuria in hypertensive T2DN rats. RBF was not altered in any of the treatment groups, and GFR was elevated in empagliflozin-treated hypertensive T2DN rats. These results indicate that empagliflozin is highly effective in controlling blood glucose levels and slows the progression of renal injury in both hypertensive type 1 and type 2 diabetic rats, especially when given in combination with lisinopril to lower blood pressure.
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Affiliation(s)
- Jan M Williams
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, 2500 North State Street, Jackson, MS, 39216, USA
| | - Sydney R Murphy
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, 2500 North State Street, Jackson, MS, 39216, USA
| | - Wenjie Wu
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, 2500 North State Street, Jackson, MS, 39216, USA
| | - Jane J Border
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, 2500 North State Street, Jackson, MS, 39216, USA
| | - Fan Fan
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, 2500 North State Street, Jackson, MS, 39216, USA
| | - Richard J Roman
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, 2500 North State Street, Jackson, MS, 39216, USA.
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Shimada S, Yang C, Kumar V, Mattson DL, Cowley AW. Acute Increase of Renal Perfusion Pressure Causes Rapid Activation of mTORC1 (Mechanistic Target Of Rapamycin Complex 1) and Leukocyte Infiltration. Hypertension 2022; 79:1180-1189. [PMID: 35291809 PMCID: PMC9098670 DOI: 10.1161/hypertensionaha.121.18643] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 02/25/2022] [Indexed: 11/16/2022]
Abstract
BACKGROUND The present study in Sprague-Dawley rats determined the effects of a rapid rise of renal perfusion pressure (RPP) upon the activation of mTOR (mechanistic target of rapamycin), and the effects upon the infiltration of CD68-positive macrophages/monocytes and CD3-positive T lymphocytes into the kidneys. METHODS RPP was elevated by 40 mm Hg for 30 minutes in male Sprague-Dawley rats while measuring renal blood flow and urine flow rate. Sham rats were studied in the same way, but RPP was not changed. Since initial studies found that the acute increase of RPP resulted in activation of mTORC1 (phosphorylation of S6S235/236), the effects of inhibition of mTORC1 with rapamycin pretreatment were then determined. RESULTS It was found that a 30-minute increase of RPP (≈40 mm Hg) resulted in an 8-fold increase of renal sodium excretion which was blunted by rapamycin treatment. Renal blood flow was not affected by the elevation of RPP. Activation of mTORC1 was observed. Significant increases in CD68-positive macrophages were found in both the cortex (intraglomerular and periglomerular regions) and in the outer medullary interstitial regions of the kidney and prevented by rapamycin treatment. Increases in CD3-positive T lymphocytes were observed exclusively in the periglomerular regions and prevented by rapamycin treatment. Upregulation of several proinflammatory markers was observed. CONCLUSIONS We conclude that elevation of RPP rapidly activates mTORC1 resulting in infiltration of immune cells into the kidney.
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Affiliation(s)
- Satoshi Shimada
- Department of Physiology, Medical College of Wisconsin, Milwaukee (S.S., C.Y., V.K., D.L.M., A.W.C.)
| | - Chun Yang
- Department of Physiology, Medical College of Wisconsin, Milwaukee (S.S., C.Y., V.K., D.L.M., A.W.C.)
| | - Vikash Kumar
- Department of Physiology, Medical College of Wisconsin, Milwaukee (S.S., C.Y., V.K., D.L.M., A.W.C.)
| | - David L Mattson
- Department of Physiology, Medical College of Wisconsin, Milwaukee (S.S., C.Y., V.K., D.L.M., A.W.C.)
- Now with: Department of Physiology, Medical College of Georgia at Augusta University (D.L.M.)
| | - Allen W Cowley
- Department of Physiology, Medical College of Wisconsin, Milwaukee (S.S., C.Y., V.K., D.L.M., A.W.C.)
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Potter JC, Whiles SA, Miles CB, Whiles JB, Mitchell MA, Biederman BE, Dawoud FM, Breuel KF, Williamson GA, Picken MM, Polichnowski AJ. Salt-Sensitive Hypertension, Renal Injury, and Renal Vasodysfunction Associated With Dahl Salt-Sensitive Rats Are Abolished in Consomic SS.BN1 Rats. J Am Heart Assoc 2021; 10:e020261. [PMID: 34689582 PMCID: PMC8751849 DOI: 10.1161/jaha.120.020261] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Background Abnormal renal hemodynamic responses to salt‐loading are thought to contribute to salt‐sensitive (SS) hypertension. However, this is based largely on studies in anesthetized animals, and little data are available in conscious SS and salt‐resistant rats. Methods and Results We assessed arterial blood pressure, renal function, and renal blood flow during administration of a 0.4% NaCl and a high‐salt (4.0% NaCl) diet in conscious, chronically instrumented 10‐ to 14‐week‐old Dahl SS and consomic SS rats in which chromosome 1 from the salt‐resistant Brown‐Norway strain was introgressed into the genome of the SS strain (SS.BN1). Three weeks of high salt intake significantly increased blood pressure (20%) and exacerbated renal injury in SS rats. In contrast, the increase in blood pressure (5%) was similarly attenuated in Brown‐Norway and SS.BN1 rats, and both strains were completely protected against renal injury. In SS.BN1 rats, 1 week of high salt intake was associated with a significant decrease in renal vascular resistance (−8%) and increase in renal blood flow (15%). In contrast, renal vascular resistance failed to decrease, and renal blood flow remained unchanged in SS rats during high salt intake. Finally, urinary sodium excretion and glomerular filtration rate were similar between SS and SS.BN1 rats during 0.4% NaCl and high salt intake. Conclusions Our data support the concept that renal vasodysfunction contributes to blood pressure salt sensitivity in Dahl SS rats, and that genes on rat chromosome 1 play a major role in modulating renal hemodynamic responses to salt loading and salt‐induced hypertension.
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Affiliation(s)
- Jacqueline C Potter
- Department of Biomedical Sciences Quillen College of MedicineEast Tennessee State University Johnson City TN
| | - Shannon A Whiles
- Department of Biomedical Sciences Quillen College of MedicineEast Tennessee State University Johnson City TN
| | - Conor B Miles
- Department of Biomedical Sciences Quillen College of MedicineEast Tennessee State University Johnson City TN
| | - Jenna B Whiles
- Department of Biomedical Sciences Quillen College of MedicineEast Tennessee State University Johnson City TN
| | - Mark A Mitchell
- Department of Biomedical Sciences Quillen College of MedicineEast Tennessee State University Johnson City TN
| | - Brianna E Biederman
- Department of Biomedical Sciences Quillen College of MedicineEast Tennessee State University Johnson City TN
| | - Febronia M Dawoud
- Department of Biomedical Sciences Quillen College of MedicineEast Tennessee State University Johnson City TN
| | - Kevin F Breuel
- Department of Obstetrics and Gynecology Quillen College of MedicineEast Tennessee State University Johnson City TN
| | - Geoffrey A Williamson
- Department of Electrical and Computer Engineering Illinois Institute of Technology Chicago IL
| | - Maria M Picken
- Department of Pathology Loyola University Medical Center Maywood IL
| | - Aaron J Polichnowski
- Department of Biomedical Sciences Quillen College of MedicineEast Tennessee State University Johnson City TN.,Center of Excellence in Inflammation, Infectious Disease and Immunity East Tennessee State University Johnson City TN
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10
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Xu L, Hu G, Qiu J, Fan Y, Ma Y, Miura T, Kohzuki M, Ito O. High Fructose-Induced Hypertension and Renal Damage Are Exaggerated in Dahl Salt-Sensitive Rats via Renal Renin-Angiotensin System Activation. J Am Heart Assoc 2021; 10:e016543. [PMID: 34259014 PMCID: PMC8483472 DOI: 10.1161/jaha.120.016543] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background High‐fructose diet (HFr) induces hypertension and renal damage. However, it has been unknown whether the HFr‐induced hypertension and renal damage are exaggerated in subjects with salt sensitivity. We tested impacts of HFr in Dahl salt‐sensitive (DS) and salt‐resistant (DR) rats. Methods and Results Male DS and DR rats were fed control diet or HFr (60% fructose) with normal‐salt content. After 12 weeks, plasma and urinary parameters, renal histological characteristics, and renal expression of renin‐angiotensin system components were examined. Furthermore, effects of renin‐angiotensin system inhibitors were also examined in DS rats fed the HFr. HFr elevated blood pressure in DS rats but not in DR rats. HFr increased urinary albumin and liver type fatty acid binding protein excretions in both rats, but the excretions were exaggerated in DS rats. HFr increased plasma lipids and uric acid in both rats, whereas HFr increased creatinine clearance in DS rats but not DR rats. Although HFr decreased plasma renin activity in DS rats, HFr‐induced glomerular injury, afferent arteriolar thickening, and renal interstitial fibrosis were exaggerated in DS rats. HFr increased renal expression of angiotensinogen, renin, (pro)renin receptor, angiotensin‐converting enzyme, and angiotensin II type 1 receptor in DS rat, whereas HFr increased only angiotensin‐converting enzyme expression and decreased renin and angiotensin II type 1 receptor expressions in DR rats. Enalapril and candesartan attenuated the HFr‐induced hypertension, albuminuria, glomerular hyperfiltration, and renal damage in DS rats. Conclusion HFr‐induced hypertension and renal damage are exaggerated in DS rats via renal renin‐angiotensin system activation, which can be controlled by renin‐angiotensin system inhibitors.
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Affiliation(s)
- Lusi Xu
- Department of Internal Medicine and Rehabilitation Science Tohoku University Graduate School of Medicine Sendai Japan
| | - Gaizun Hu
- Department of Pharmacology and Toxicology School of Medicine Virginia Commonwealth University Richmond VA
| | - Jiahe Qiu
- Department of Internal Medicine and Rehabilitation Science Tohoku University Graduate School of Medicine Sendai Japan
| | - Yuxuan Fan
- Department of Internal Medicine and Rehabilitation Science Tohoku University Graduate School of Medicine Sendai Japan
| | - Yixuan Ma
- Department of Internal Medicine and Rehabilitation Science Tohoku University Graduate School of Medicine Sendai Japan
| | - Takahiro Miura
- Department of Internal Medicine and Rehabilitation Science Tohoku University Graduate School of Medicine Sendai Japan
| | - Masahiro Kohzuki
- Department of Internal Medicine and Rehabilitation Science Tohoku University Graduate School of Medicine Sendai Japan
| | - Osamu Ito
- Department of Internal Medicine and Rehabilitation Science Tohoku University Graduate School of Medicine Sendai Japan.,Division of General Medicine and Rehabilitation Tohoku Medical and Pharmaceutical University Faculty of Medicine Sendai Japan
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11
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Eicosanoid blood vessel regulation in physiological and pathological states. Clin Sci (Lond) 2021; 134:2707-2727. [PMID: 33095237 DOI: 10.1042/cs20191209] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 09/26/2020] [Accepted: 10/09/2020] [Indexed: 12/15/2022]
Abstract
Arachidonic acid can be metabolized in blood vessels by three primary enzymatic pathways; cyclooxygenase (COX), lipoxygenase (LO), and cytochrome P450 (CYP). These eicosanoid metabolites can influence endothelial and vascular smooth muscle cell function. COX metabolites can cause endothelium-dependent dilation or constriction. Prostaglandin I2 (PGI2) and thromboxane (TXA2) act on their respective receptors exerting opposing actions with regard to vascular tone and platelet aggregation. LO metabolites also influence vascular tone. The 12-LO metabolite 12S-hydroxyeicosatrienoic acid (12S-HETE) is a vasoconstrictor whereas the 15-LO metabolite 11,12,15-trihydroxyeicosatrienoic acid (11,12,15-THETA) is an endothelial-dependent hyperpolarizing factor (EDHF). CYP enzymes produce two types of eicosanoid products: EDHF vasodilator epoxyeicosatrienoic acids (EETs) and the vasoconstrictor 20-HETE. The less-studied cross-metabolites generated from arachidonic acid metabolism by multiple pathways can also impact vascular function. Likewise, COX, LO, and CYP vascular eicosanoids interact with paracrine and hormonal factors such as the renin-angiotensin system and endothelin-1 (ET-1) to maintain vascular homeostasis. Imbalances in endothelial and vascular smooth muscle cell COX, LO, and CYP metabolites in metabolic and cardiovascular diseases result in vascular dysfunction. Restoring the vascular balance of eicosanoids by genetic or pharmacological means can improve vascular function in metabolic and cardiovascular diseases. Nevertheless, future research is necessary to achieve a more complete understanding of how COX, LO, CYP, and cross-metabolites regulate vascular function in physiological and pathological states.
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12
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Zhang C, Fang X, Zhang H, Gao W, Hsu HJ, Roman RJ, Fan F. Genetic susceptibility of hypertension-induced kidney disease. Physiol Rep 2021; 9:e14688. [PMID: 33377622 PMCID: PMC7772938 DOI: 10.14814/phy2.14688] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 11/22/2020] [Accepted: 11/27/2020] [Indexed: 02/06/2023] Open
Abstract
Hypertension is the second leading cause of end-stage renal disease (ESRD) after diabetes mellitus. The significant differences in the incidence of hypertensive ESRD between different patient populations worldwide and patients with and without family history indicate that genetic determinants play an important role in the onset and progression of this disease. Recent studies have identified genetic variants and pathways that may contribute to the alteration of renal function. Mechanisms involved include affecting renal hemodynamics (the myogenic and tubuloglomerular feedback responses); increasing the production of reactive oxygen species in the tubules; altering immune cell function; changing the number, structure, and function of podocytes that directly cause glomerular damage. Studies with hypertensive animal models using substitution mapping and gene knockout strategies have identified multiple candidate genes associated with the development of hypertension and subsequent renal injury. Genome-wide association studies have implicated genetic variants in UMOD, MYH9, APOL-1, SHROOM3, RAB38, and DAB2 have a higher risk for ESRD in hypertensive patients. These findings provide genetic evidence of potential novel targets for drug development and gene therapy to design individualized treatment of hypertension and related renal injury.
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Affiliation(s)
- Chao Zhang
- Department of Pharmacology and ToxicologyUniversity of Mississippi Medical CenterJacksonMississippiUSA
- Department of UrologyZhongshan HospitalFudan UniversityShanghaiChina
| | - Xing Fang
- Department of Pharmacology and ToxicologyUniversity of Mississippi Medical CenterJacksonMississippiUSA
| | - Huawei Zhang
- Department of Pharmacology and ToxicologyUniversity of Mississippi Medical CenterJacksonMississippiUSA
| | - Wenjun Gao
- Department of Pharmacology and ToxicologyUniversity of Mississippi Medical CenterJacksonMississippiUSA
- Department of UrologyZhongshan HospitalFudan UniversityShanghaiChina
| | - Han Jen Hsu
- Department of UrologyZhongshan HospitalFudan UniversityShanghaiChina
| | - Richard J. Roman
- Department of Pharmacology and ToxicologyUniversity of Mississippi Medical CenterJacksonMississippiUSA
| | - Fan Fan
- Department of Pharmacology and ToxicologyUniversity of Mississippi Medical CenterJacksonMississippiUSA
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13
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Fan F, Geurts AM, Pabbidi MR, Ge Y, Zhang C, Wang S, Liu Y, Gao W, Guo Y, Li L, He X, Lv W, Muroya Y, Hirata T, Prokop J, Booz GW, Jacob HJ, Roman RJ. A Mutation in γ-Adducin Impairs Autoregulation of Renal Blood Flow and Promotes the Development of Kidney Disease. J Am Soc Nephrol 2020; 31:687-700. [PMID: 32029431 DOI: 10.1681/asn.2019080784] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 12/14/2019] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND The genes and mechanisms involved in the association between diabetes or hypertension and CKD risk are unclear. Previous studies have implicated a role for γ-adducin (ADD3), a cytoskeletal protein encoded by Add3. METHODS We investigated renal vascular function in vitro and in vivo and the susceptibility to CKD in rats with wild-type or mutated Add3 and in genetically modified rats with overexpression or knockout of ADD3. We also studied glomeruli and primary renal vascular smooth muscle cells isolated from these rats. RESULTS This study identified a K572Q mutation in ADD3 in fawn-hooded hypertensive (FHH) rats-a mutation previously reported in Milan normotensive (MNS) rats that also develop kidney disease. Using molecular dynamic simulations, we found that this mutation destabilizes a critical ADD3-ACTIN binding site. A reduction of ADD3 expression in membrane fractions prepared from the kidney and renal vascular smooth muscle cells of FHH rats was associated with the disruption of the F-actin cytoskeleton. Compared with renal vascular smooth muscle cells from Add3 transgenic rats, those from FHH rats had elevated membrane expression of BKα and BK channel current. FHH and Add3 knockout rats exhibited impairments in the myogenic response of afferent arterioles and in renal blood flow autoregulation, which were rescued in Add3 transgenic rats. We confirmed these findings in a genetic complementation study that involved crossing FHH and MNS rats that share the ADD3 mutation. Add3 transgenic rats showed attenuation of proteinuria, glomerular injury, and kidney fibrosis with aging and mineralocorticoid-induced hypertension. CONCLUSIONS This is the first report that a mutation in ADD3 that alters ACTIN binding causes renal vascular dysfunction and promotes the susceptibility to kidney disease.
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Affiliation(s)
- Fan Fan
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Aron M Geurts
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Mallikarjuna R Pabbidi
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Ying Ge
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Chao Zhang
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Shaoxun Wang
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Yedan Liu
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Wenjun Gao
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Ya Guo
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Longyang Li
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Xiaochen He
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Wenshan Lv
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Yoshikazu Muroya
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Takashi Hirata
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Jeremy Prokop
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan
| | - George W Booz
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Howard J Jacob
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Richard J Roman
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi;
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14
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Conflicting Roles of 20-HETE in Hypertension and Stroke. Int J Mol Sci 2019; 20:ijms20184500. [PMID: 31514409 PMCID: PMC6770042 DOI: 10.3390/ijms20184500] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 08/28/2019] [Accepted: 09/08/2019] [Indexed: 12/15/2022] Open
Abstract
Hypertension is the most common modifiable risk factor for stroke, and understanding the underlying mechanisms of hypertension and hypertension-related stroke is crucial. 20-hydroxy-5, 8, 11, 14-eicosatetraenoic acid (20-HETE), which plays an important role in vasoconstriction, autoregulation, endothelial dysfunction, angiogenesis, inflammation, and blood-brain barrier integrity, has been linked to hypertension and stroke. 20-HETE can promote hypertension by potentiating the vascular response to vasoconstrictors; it also can reduce blood pressure by inhibition of sodium transport in the kidney. The production of 20-HETE is elevated after the onset of both ischemic and hemorrhagic strokes; on the other hand, subjects with genetic variants in CYP4F2 and CYP4A11 that reduce 20-HETE production are more susceptible to stroke. This review summarizes recent genetic variants in CYP4F2, and CYP4A11 influencing 20-HETE production and discusses the role of 20-HETE in hypertension and the susceptibility to the onset, progression, and prognosis of ischemic and hemorrhagic strokes.
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15
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Zhang C, He X, Murphy SR, Zhang H, Wang S, Ge Y, Gao W, Williams JM, Geurts AM, Roman RJ, Fan F. Knockout of Dual-Specificity Protein Phosphatase 5 Protects Against Hypertension-Induced Renal Injury. J Pharmacol Exp Ther 2019; 370:206-217. [PMID: 31118214 PMCID: PMC6636243 DOI: 10.1124/jpet.119.258954] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 05/16/2019] [Indexed: 12/28/2022] Open
Abstract
Dual-specificity protein phosphatase 5 (DUSP5) is a member of the tyrosine-threonine phosphatase family with the ability to dephosphorylate and inactivate extracellular signal-related kinase (ERK). The present study investigates whether knockout (KO) of Dusp5 improves renal hemodynamics and protects against hypertension-induced renal injury. The renal expression of DUSP5 was reduced, and the levels of phosphorylated (p) ERK1/2 and p-protein kinase C (PKC) α were elevated in the KO rats. KO of Dusp5 enhanced the myogenic tone of the renal afferent arteriole and interlobular artery in vitro with or without induction of deoxycorticosterone acetate-salt hypertension. Inhibition of ERK1/2 and PKC diminished the myogenic response to a greater extent in Dusp5 KO rats. Autoregulation of renal blood flow was significantly impaired in hypertensive wild-type (WT) rats but remained intact in Dusp5 KO animals. Proteinuria was markedly decreased in hypertensive KO versus WT rats. The degree of glomerular injury was reduced, and the expression of nephrin in the glomerulus was higher in hypertensive Dusp5 KO rats. Renal fibrosis and medullary protein cast formation were attenuated in hypertensive Dusp5 KO rats in association with decreased expression of monocyte chemoattractant protein 1, transforming growth factor-β1, matrix metalloproteinase (MMP) 2, and MMP9. These results indicate that KO of Dusp5 protects against hypertension-induced renal injury, at least in part, by maintaining the myogenic tone of the renal vasculature and extending the range of renal blood flow autoregulation to higher pressures, which diminish glomerular injury, protein cast formation, macrophage infiltration, and epithelial-mesenchymal transformation in the kidney. SIGNIFICANCE STATEMENT: Dual-specificity protein phosphatase 5 (DUSP5) is a tyrosine-threonine phosphatase that inactivates extracellular signal-related kinase (ERK). We previously reported that knockout (KO) of Dusp5 enhanced the myogenic response and autoregulation in the cerebral circulation. The present study investigates whether KO of DUSP5 improves renal hemodynamics and protects against hypertension-induced renal injury. Downregulation of DUSP5 enhanced the myogenic tone of renal arteriole and artery and autoregulation of renal blood flow in association with reduced proteinuria, glomerular injury, and interstitial fibrosis after the induction of hypertension. Inhibition of ERK1/2 and protein kinase C diminished the myogenic response to a greater extent in Dusp5 KO rats. These results suggest that DUSP5 might be a viable drug target for the treatment of hypertension nephropathy.
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Affiliation(s)
- Chao Zhang
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
| | - Xiaochen He
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
| | - Sydney R Murphy
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
| | - Huawei Zhang
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
| | - Shaoxun Wang
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
| | - Ying Ge
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
| | - Wenjun Gao
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
| | - Jan M Williams
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
| | - Aron M Geurts
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
| | - Richard J Roman
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
| | - Fan Fan
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center. Jackson, Mississippi (C.Z., X.H., S.R.M., H.Z., S.W., Y.G., W.G., J.M.W., R.J.R., F.F.); Department of Urology, Zhongshan Hospital, Fudan University. Shanghai, China (C.Z., W.G.); and Department of Physiology, Medical College of Wisconsin. Milwaukee, Wisconsin (A.M.G.)
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16
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Zhang C, Booz GW, Yu Q, He X, Wang S, Fan F. Conflicting roles of 20-HETE in hypertension and renal end organ damage. Eur J Pharmacol 2018; 833:190-200. [PMID: 29886242 PMCID: PMC6057804 DOI: 10.1016/j.ejphar.2018.06.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2018] [Revised: 06/05/2018] [Accepted: 06/06/2018] [Indexed: 12/12/2022]
Abstract
20-HETE is a cytochrome P450-derived metabolite of arachidonic acid that has both pro- and anti-hypertensive actions that result from modulation of vascular and kidney function. In the vasculature, 20-HETE sensitizes vascular smooth muscle cells to constrictor stimuli and increases myogenic tone. By promoting smooth muscle cell migration and proliferation, as well as by acting on the vascular endothelium to cause endothelial dysfunction, angiotensin converting enzyme (ACE) expression, and inflammation, 20-HETE contributes to adverse vascular remodeling and increased blood pressure. A G protein-coupled receptor was recently identified as the effector for the vascular actions of 20-HETE. In addition, evidence suggests that 20-HETE contributes to hypertension via positive regulation of the renin-angiotensin-aldosterone system, as well as by causing renal fibrosis. On the other hand, 20-HETE exerts anti-hypertensive actions by inhibiting sodium reabsorption by the kidney in both the proximal tubule and thick ascending limb of Henle. This review discusses the pro- and anti-hypertensive roles of 20-HETE in the pathogenesis of hypertension-associated renal disease, the association of gene polymorphisms of cytochrome P450 enzymes with the development of hypertension and renal end organ damage in humans, and 20-HETE related pharmaceutical agents.
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MESH Headings
- Animals
- Antihypertensive Agents/metabolism
- Antihypertensive Agents/pharmacology
- Arachidonic Acid/metabolism
- Cytochrome P-450 Enzyme System/genetics
- Cytochrome P-450 Enzyme System/metabolism
- Endothelium, Vascular/cytology
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/physiopathology
- Fibrosis
- Humans
- Hydroxyeicosatetraenoic Acids/pharmacology
- Hydroxyeicosatetraenoic Acids/physiology
- Hypertension/complications
- Hypertension/drug therapy
- Hypertension/metabolism
- Hypertension/physiopathology
- Kidney/metabolism
- Kidney/pathology
- Kidney/physiopathology
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/physiopathology
- Peptidyl-Dipeptidase A/metabolism
- Polymorphism, Genetic
- Receptors, G-Protein-Coupled/metabolism
- Renal Elimination/physiology
- Renal Insufficiency/drug therapy
- Renal Insufficiency/etiology
- Renal Insufficiency/metabolism
- Renal Insufficiency/physiopathology
- Renin-Angiotensin System/physiology
- Sodium/metabolism
- Vascular Remodeling/physiology
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Affiliation(s)
- Chao Zhang
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, 2500 N. State Street, Jackson, MS 39216, USA; Department of Urology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - George W Booz
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, 2500 N. State Street, Jackson, MS 39216, USA
| | - Qing Yu
- Department of Nephrology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Xiaochen He
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, 2500 N. State Street, Jackson, MS 39216, USA
| | - Shaoxun Wang
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, 2500 N. State Street, Jackson, MS 39216, USA
| | - Fan Fan
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, 2500 N. State Street, Jackson, MS 39216, USA.
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17
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Abstract
20-HETE, the ω-hydroxylation product of arachidonic acid catalyzed by enzymes of the cytochrome P450 (CYP) 4A and 4F gene families, is a bioactive lipid mediator with potent effects on the vasculature including stimulation of smooth muscle cell contractility, migration and proliferation as well as activation of endothelial cell dysfunction and inflammation. Clinical studies have shown elevated levels of plasma and urinary 20-HETE in human diseases and conditions such as hypertension, obesity and metabolic syndrome, myocardial infarction, stroke, and chronic kidney diseases. Studies of polymorphic associations also suggest an important role for 20-HETE in hypertension, stroke and myocardial infarction. Animal models of increased 20-HETE production are hypertensive and are more susceptible to cardiovascular injury. The current review summarizes recent findings that focus on the role of 20-HETE in the regulation of vascular and cardiac function and its contribution to the pathology of vascular and cardiac diseases.
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Affiliation(s)
- Petra Rocic
- Department of Pharmacology, New York Medical College School of Medicine, Valhalla, NY, United States
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18
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Ge Y, Fan F, Didion SP, Roman RJ. Impaired myogenic response of the afferent arteriole contributes to the increased susceptibility to renal disease in Milan normotensive rats. Physiol Rep 2018; 5:5/3/e13089. [PMID: 28193784 PMCID: PMC5309574 DOI: 10.14814/phy2.13089] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 11/25/2016] [Accepted: 12/01/2016] [Indexed: 12/23/2022] Open
Abstract
Milan normotensive (MNS) rats are more susceptible to the development of renal disease than Milan hypertensive (MHS) rats, but the genes and pathways involved are unknown. This study compared the myogenic response of isolated perfused afferent arterioles (Af‐Art) and autoregulation of renal blood flow (RBF) and glomerular capillary pressure (Pgc) in 6–9‐week‐old MNS and MHS rats. The diameter of the Af‐Art of MHS rats decreased significantly from 14.3 ± 0.5 to 11.5 ± 0.6 μm when perfusion pressure was elevated from 60 to 120 mmHg. In contrast, the diameter of Af‐Art of MNS rats did not decrease. RBF was well autoregulated in MHS rats, but it increased by 26% in MNS rats. Pgc rose by 11 mmHg when renal perfusion pressure (RPP) was increased from 100 to 140 mmHg in MNS but not in MHS rats. Protein excretion increased from 10 ± 1 to 245 ± 36 mg/day in MNS rats as they aged from 3 to 11 months but it did not increase in MHS rats. We also compared the development of proteinuria in MNS and MHS rats following the induction of diabetes with streptozotocin. Protein excretion rose from 16 ± 3 to 234 ± 43 mg/day in MNS rats, but it remained unaltered in MHS rats. These data indicate that the myogenic response of the Af‐art is impaired in MNS rats and increased transmission of pressure to the glomerulus may contribute to renal injury in MNS rats similar to what is seen in fawn‐hooded hypertensive and Dahl salt‐sensitive rats.
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Affiliation(s)
- Ying Ge
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Fan Fan
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Sean P Didion
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Richard J Roman
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
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19
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Shekhar S, Cunningham MW, Pabbidi MR, Wang S, Booz GW, Fan F. Targeting vascular inflammation in ischemic stroke: Recent developments on novel immunomodulatory approaches. Eur J Pharmacol 2018; 833:531-544. [PMID: 29935175 DOI: 10.1016/j.ejphar.2018.06.028] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 06/02/2018] [Accepted: 06/19/2018] [Indexed: 10/28/2022]
Abstract
Ischemic stroke is a devastating and debilitating medical condition with limited therapeutic options. However, accumulating evidence indicates a central role of inflammation in all aspects of stroke including its initiation, the progression of injury, and recovery or wound healing. A central target of inflammation is disruption of the blood brain barrier or neurovascular unit. Here we discuss recent developments in identifying potential molecular targets and immunomodulatory approaches to preserve or protect barrier function and limit infarct damage and functional impairment. These include blocking harmful inflammatory signaling in endothelial cells, microglia/macrophages, or Th17/γδ T cells with biologics, third generation epoxyeicosatrienoic acid (EET) analogs with extended half-life, and miRNA antagomirs. Complementary beneficial pathways may be enhanced by miRNA mimetics or hyperbaric oxygenation. These immunomodulatory approaches could be used to greatly expand the therapeutic window for thrombolytic treatment with tissue plasminogen activator (t-PA). Moreover, nanoparticle technology allows for the selective targeting of endothelial cells for delivery of DNA/RNA oligonucleotides and neuroprotective drugs. In addition, although likely detrimental to the progression of ischemic stroke by inducing inflammation, oxidative stress, and neuronal cell death, 20-HETE may also reduce susceptibility of onset of ischemic stroke by maintaining autoregulation of cerebral blood flow. Although the interaction between inflammation and stroke is multifaceted, a better understanding of the mechanisms behind the pro-inflammatory state at all stages will hopefully help in developing novel immunomodulatory approaches to improve mortality and functional outcome of those inflicted with ischemic stroke.
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Affiliation(s)
- Shashank Shekhar
- Department of Neurology, University of Mississippi Medical Center, Jackson, MS, USA; Institute of Clinical Medicine, University of Turku, Turku, Finland
| | - Mark W Cunningham
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS, USA
| | - Mallikarjuna R Pabbidi
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS, USA
| | - Shaoxun Wang
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS, USA
| | - George W Booz
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS, USA
| | - Fan Fan
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS, USA.
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Wang H, Romero CA, Masjoan Juncos JX, Monu SR, Peterson EL, Carretero OA. Effect of salt intake on afferent arteriolar dilatation: role of connecting tubule glomerular feedback (CTGF). Am J Physiol Renal Physiol 2017; 313:F1209-F1215. [PMID: 28835421 DOI: 10.1152/ajprenal.00320.2017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 08/10/2017] [Accepted: 08/16/2017] [Indexed: 01/13/2023] Open
Abstract
Afferent arteriole (Af-Art) resistance is modulated by two intrinsic nephron feedbacks: 1) the vasoconstrictor tubuloglomerular feedback (TGF) mediated by Na+-K+-2Cl- cotransporters (NKCC2) in the macula densa and blocked by furosemide and 2) the vasodilator connecting tubule glomerular feedback (CTGF), mediated by epithelial Na+ channels (ENaC) in the connecting tubule and blocked by benzamil. High salt intake reduces Af-Art vasoconstrictor ability in Dahl salt-sensitive rats (Dahl SS). Previously, we measured CTGF indirectly, by differences between TGF responses with and without CTGF inhibition. We recently developed a new method to measure CTGF more directly by simultaneously inhibiting NKCC2 and the Na+/H+ exchanger (NHE). We hypothesize that in vivo during simultaneous inhibition of NKCC2 and NHE, CTGF causes an Af-Art dilatation revealed by an increase in stop-flow pressure (PSF) in Dahl SS and that is enhanced with a high salt intake. In the presence of furosemide alone, increasing nephron perfusion did not change the PSF in either Dahl salt-resistant rats (Dahl SR) or Dahl SS. When furosemide and an NHE inhibitor, dimethylamiloride, were perfused simultaneously, an increase in tubular flow caused Af-Art dilatation that was demonstrated by an increase in PSF. This increase was greater in Dahl SS [4.5 ± 0.4 (SE) mmHg] than in Dahl SR (2.5 ± 0.3 mmHg; P < 0.01). We confirmed that CTGF causes this vasodilation, since benzamil completely blocked this effect. However, a high salt intake did not augment the Af-Art dilatation. We conclude that during simultaneous inhibition of NKCC2 and NHE in the nephron, CTGF induces Af-Art dilatation and a high salt intake failed to enhance this effect.
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Affiliation(s)
- Hong Wang
- Hypertension and Vascular Research Division, Department of Internal Medicine, Henry Ford Hospital, Detroit, Michigan; and
| | - Cesar A Romero
- Hypertension and Vascular Research Division, Department of Internal Medicine, Henry Ford Hospital, Detroit, Michigan; and
| | - J X Masjoan Juncos
- Hypertension and Vascular Research Division, Department of Internal Medicine, Henry Ford Hospital, Detroit, Michigan; and
| | - Sumit R Monu
- Hypertension and Vascular Research Division, Department of Internal Medicine, Henry Ford Hospital, Detroit, Michigan; and
| | - Edward L Peterson
- Department of Public Health Sciences, Henry Ford Hospital, Detroit, Michigan
| | - Oscar A Carretero
- Hypertension and Vascular Research Division, Department of Internal Medicine, Henry Ford Hospital, Detroit, Michigan; and
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Fan F, Roman RJ. Effect of Cytochrome P450 Metabolites of Arachidonic Acid in Nephrology. J Am Soc Nephrol 2017; 28:2845-2855. [PMID: 28701518 DOI: 10.1681/asn.2017030252] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Thirty-five years ago, a third pathway for the metabolism of arachidonic acid by cytochrome P450 enzymes emerged. Subsequent work revealed that 20-hydroxyeicosatetraenoic and epoxyeicosatrienoic acids formed by these pathways have essential roles in the regulation of renal tubular and vascular function. Sequence variants in the genes that produce 20-hydroxyeicosatetraenoic acid are associated with hypertension in humans, whereas the evidence supporting a role for variants in the genes that alter levels of epoxyeicosatrienoic acids is less convincing. Studies in animal models suggest that changes in the production of cytochrome P450 eicosanoids alter BP. However, the mechanisms involved remain controversial, especially for 20-hydroxyeicosatetraenoic acid, which has both vasoconstrictive and natriuretic actions. Epoxyeicosatrienoic acids are vasodilators with anti-inflammatory properties that oppose the development of hypertension and CKD; 20-hydroxyeicosatetraenoic acid levels are elevated after renal ischemia and may protect against injury. Levels of this eicosanoid are also elevated in polycystic kidney disease and may contribute to cyst formation. Our review summarizes the emerging evidence that cytochrome P450 eicosanoids have a role in the pathogenesis of hypertension, polycystic kidney disease, AKI, and CKD.
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Affiliation(s)
- Fan Fan
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Richard J Roman
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
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22
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Ungvari Z, Tarantini S, Kirkpatrick AC, Csiszar A, Prodan CI. Cerebral microhemorrhages: mechanisms, consequences, and prevention. Am J Physiol Heart Circ Physiol 2017; 312:H1128-H1143. [PMID: 28314762 PMCID: PMC5495931 DOI: 10.1152/ajpheart.00780.2016] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 02/22/2017] [Accepted: 03/09/2017] [Indexed: 12/20/2022]
Abstract
The increasing prevalence of multifocal cerebral microhemorrhages (CMHs, also known as "cerebral microbleeds") is a significant, newly recognized problem in the aging population of the Western world. CMHs are associated with rupture of small intracerebral vessels and are thought to progressively impair neuronal function, potentially contributing to cognitive decline, geriatric psychiatric syndromes, and gait disorders. Clinical studies show that aging and hypertension significantly increase prevalence of CMHs. CMHs are also now recognized by the National Institutes of Health as a major factor in Alzheimer's disease pathology. Moreover, the presence of CMHs is an independent risk factor for subsequent larger intracerebral hemorrhages. In this article, we review the epidemiology, detection, risk factors, clinical significance, and pathogenesis of CMHs. The potential age-related cellular mechanisms underlying the development of CMHs are discussed, with a focus on the structural determinants of microvascular fragility, age-related alterations in cerebrovascular adaptation to hypertension, the role of oxidative stress and matrix metalloproteinase activation, and the deleterious effects of arterial stiffening, increased pulse pressure, and impaired myogenic autoregulatory protection on the brain microvasculature. Finally, we examine potential treatments for the prevention of CMHs based on the proposed model of aging- and hypertension-dependent activation of the reactive oxygen species-matrix metalloproteinases axis, and we discuss critical questions to be addressed by future studies.
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Affiliation(s)
- Zoltan Ungvari
- Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma; .,Translational Geroscience Laboratory, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Stefano Tarantini
- Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma.,Translational Geroscience Laboratory, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Angelia C Kirkpatrick
- Veterans Affairs Medical Center, Oklahoma City, Oklahoma.,Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma; and
| | - Anna Csiszar
- Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma.,Translational Geroscience Laboratory, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Calin I Prodan
- Department of Neurology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
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23
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Toth P, Tarantini S, Csiszar A, Ungvari Z. Functional vascular contributions to cognitive impairment and dementia: mechanisms and consequences of cerebral autoregulatory dysfunction, endothelial impairment, and neurovascular uncoupling in aging. Am J Physiol Heart Circ Physiol 2017; 312:H1-H20. [PMID: 27793855 PMCID: PMC5283909 DOI: 10.1152/ajpheart.00581.2016] [Citation(s) in RCA: 320] [Impact Index Per Article: 45.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 10/10/2016] [Accepted: 10/26/2016] [Indexed: 12/16/2022]
Abstract
Increasing evidence from epidemiological, clinical and experimental studies indicate that age-related cerebromicrovascular dysfunction and microcirculatory damage play critical roles in the pathogenesis of many types of dementia in the elderly, including Alzheimer's disease. Understanding and targeting the age-related pathophysiological mechanisms that underlie vascular contributions to cognitive impairment and dementia (VCID) are expected to have a major role in preserving brain health in older individuals. Maintenance of cerebral perfusion, protecting the microcirculation from high pressure-induced damage and moment-to-moment adjustment of regional oxygen and nutrient supply to changes in demand are prerequisites for the prevention of cerebral ischemia and neuronal dysfunction. This overview discusses age-related alterations in three main regulatory paradigms involved in the regulation of cerebral blood flow (CBF): cerebral autoregulation/myogenic constriction, endothelium-dependent vasomotor function, and neurovascular coupling responses responsible for functional hyperemia. The pathophysiological consequences of cerebral microvascular dysregulation in aging are explored, including blood-brain barrier disruption, neuroinflammation, exacerbation of neurodegeneration, development of cerebral microhemorrhages, microvascular rarefaction, and ischemic neuronal dysfunction and damage. Due to the widespread attention that VCID has captured in recent years, the evidence for the causal role of cerebral microvascular dysregulation in cognitive decline is critically examined.
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Affiliation(s)
- Peter Toth
- Department of Geriatric Medicine, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
- Department of Neurosurgery and Szentagothai Research Center, University of Pecs, Pecs, Hungary; and
| | - Stefano Tarantini
- Department of Geriatric Medicine, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Anna Csiszar
- Department of Geriatric Medicine, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
- Department of Medical Physics and Informatics, University of Szeged, Szeged, Hungary
| | - Zoltan Ungvari
- Department of Geriatric Medicine, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma;
- Department of Medical Physics and Informatics, University of Szeged, Szeged, Hungary
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24
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Fan F, Pabbidi MR, Ge Y, Li L, Wang S, Mims PN, Roman RJ. Knockdown of Add3 impairs the myogenic response of renal afferent arterioles and middle cerebral arteries. Am J Physiol Renal Physiol 2016; 312:F971-F981. [PMID: 27927653 PMCID: PMC5495887 DOI: 10.1152/ajprenal.00529.2016] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2016] [Revised: 11/29/2016] [Accepted: 12/05/2016] [Indexed: 11/22/2022] Open
Abstract
We have reported that the myogenic response of the renal afferent arteriole (Af-art) and middle cerebral artery (MCA) and autoregulation of renal and cerebral blood flow are impaired in Fawn-Hooded Hypertensive (FHH) rats. Transfer of a region of chromosome 1 containing γ-adducin (Add3) from the Brown Norway rat rescued the vascular dysfunction and the development of renal disease. To examine whether Add3 is a viable candidate gene altering renal and cerebral hemodynamics in FHH rats, we knocked down the expression of Add3 in rat Af-arts and MCAs cultured for 36-h using a 27-mer Dicer-substrate short interfering RNA (DsiRNA). Control Af-arts constricted by 10 ± 1% in response to an elevation in pressure from 60 to 120 mmHg but dilated by 4 ± 3% when treated with Add3 DsiRNA. Add3 DsiRNA had no effect on the vasoconstrictor response of the Af-art to norepinephrine (10-7 M). Add3 DsiRNA had a similar effect on the attenuation of the myogenic response in the MCA. Peak potassium currents were threefold higher in smooth muscle cells isolated from Af-arts or MCAs transfected with Add3 DsiRNA than in nontransfected cells isolated from the same vessels. This is the first study demonstrating that Add3 plays a role in the regulation of potassium channel function and vascular reactivity. It supports the hypothesis that sequence variants in Add3, which we previously identified in FHH rats, may play a causal role in the impaired myogenic response and autoregulation in the renal and cerebral circulation.
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Affiliation(s)
- Fan Fan
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Mallikarjuna R Pabbidi
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Ying Ge
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Longyang Li
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Shaoxun Wang
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Paige N Mims
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Richard J Roman
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
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Roshanravan H, Kim EY, Dryer SE. 20-Hydroxyeicosatetraenoic Acid (20-HETE) Modulates Canonical Transient Receptor Potential-6 (TRPC6) Channels in Podocytes. Front Physiol 2016; 7:351. [PMID: 27630573 PMCID: PMC5005377 DOI: 10.3389/fphys.2016.00351] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 08/02/2016] [Indexed: 01/08/2023] Open
Abstract
The arachidonic acid metabolite 20-hydroxyeicosatetraenoic acid (20-HETE) regulates renal function, including changes in glomerular function evoked during tubuloglomerular feedback (TGF). This study describes the cellular actions of 20-HETE on cultured podocytes, assessed by whole-cell recordings from cultured podocytes combined with pharmacological and cell-biological manipulations of cells. Bath superfusion of 20-HETE activates cationic currents that are blocked by the pan-TRP blocker SKF-96365 and by 50 μM La3+, and which are attenuated after siRNA knockdown of TRPC6 subunits. Similar currents are evoked by a membrane-permeable analog of diacylgycerol (OAG), but OAG does not occlude responses to maximally-activating concentrations of 20-HETE (20 μM). Exposure to 20-HETE also increased steady-state surface abundance of TRPC6 subunits in podocytes as assessed by cell-surface biotinylation assays, and increased cytosolic concentrations of reactive oxygen species (ROS). TRPC6 activation by 20-HETE was eliminated in cells pretreated with TEMPOL, a membrane-permeable superoxide dismutase mimic. Activation of TRPC6 by 20-HETE was also blocked when whole-cell recording pipettes contained GDP-βS, indicating a role for either small or heterotrimeric G proteins in the transduction cascade. Responses to 20-HETE were eliminated by siRNA knockdown of podocin, a protein that organizes NADPH oxidase complexes with TRPC6 subunits in this cell type. In summary, modulation of ionic channels in podocytes may contribute to glomerular actions of 20-HETE.
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Affiliation(s)
- Hila Roshanravan
- Department of Biology and Biochemistry, University of Houston Houston, TX, USA
| | - Eun Y Kim
- Department of Biology and Biochemistry, University of Houston Houston, TX, USA
| | - Stuart E Dryer
- Department of Biology and Biochemistry, University of HoustonHouston, TX, USA; Division of Nephrology, Baylor College of MedicineHouston, TX, USA
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26
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McPherson KC, Taylor L, Johnson AC, Didion SP, Geurts AM, Garrett MR, Williams JM. Early development of podocyte injury independently of hyperglycemia and elevations in arterial pressure in nondiabetic obese Dahl SS leptin receptor mutant rats. Am J Physiol Renal Physiol 2016; 311:F793-F804. [PMID: 27465994 DOI: 10.1152/ajprenal.00590.2015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 07/25/2016] [Indexed: 01/05/2023] Open
Abstract
The current study examined the effect of obesity on the development of renal injury within the genetic background of the Dahl salt-sensitive rat with a dysfunctional leptin receptor derived from zinc-finger nucleases (SSLepRmutant strain). At 6 wk of age, body weight was 35% higher in the SSLepRmutant strain compared with SSWT rats and remained elevated throughout the entire study. The SSLepRmutant strain exhibited impaired glucose tolerance and increased plasma insulin levels at 6 wk of age, suggesting insulin resistance while SSWT rats did not. However, blood glucose levels were normal throughout the course of the study. Systolic arterial pressure (SAP) was similar between the two strains from 6 to 10 wk of age. However, by 18 wk of age, the development of hypertension was more severe in the SSLepRmutant strain compared with SSWT rats (201 ± 10 vs. 155 ± 3 mmHg, respectively). Interestingly, proteinuria was substantially higher at 6 wk of age in the SSLepRmutant strain vs. SSWT rats (241 ± 27 vs. 24 ± 2 mg/day, respectively) and remained elevated until the end of the study. The kidneys from the SSLepRmutant strain displayed significant glomerular injury, including podocyte foot process effacement and lipid droplets compared with SSWT rats as early as 6 wk of age. By 18 wk of age, plasma creatinine levels were twofold higher in the SSLepRmutant strain vs. SSWT rats, suggesting the presence of chronic kidney disease (CKD). Overall, these results indicate that the SSLepRmutant strain develops podocyte injury and proteinuria independently of hyperglycemia and elevated arterial pressure that later progresses to CKD.
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Affiliation(s)
- Kasi C McPherson
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi; and
| | - Lateia Taylor
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi; and
| | - Ashley C Johnson
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi; and
| | - Sean P Didion
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi; and
| | - Aron M Geurts
- Human Molecular Genetics Center, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Michael R Garrett
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi; and
| | - Jan M Williams
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi; and
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Fan F, Ge Y, Lv W, Elliott MR, Muroya Y, Hirata T, Booz GW, Roman RJ. Molecular mechanisms and cell signaling of 20-hydroxyeicosatetraenoic acid in vascular pathophysiology. Front Biosci (Landmark Ed) 2016; 21:1427-63. [PMID: 27100515 DOI: 10.2741/4465] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Cytochrome P450s enzymes catalyze the metabolism of arachidonic acid to epoxyeicosatrienoic acids (EETs), dihydroxyeicosatetraenoic acid and hydroxyeicosatetraeonic acid (HETEs). 20-HETE is a vasoconstrictor that depolarizes vascular smooth muscle cells by blocking K+ channels. EETs serve as endothelial derived hyperpolarizing factors. Inhibition of the formation of 20-HETE impairs the myogenic response and autoregulation of renal and cerebral blood flow. Changes in the formation of EETs and 20-HETE have been reported in hypertension and drugs that target these pathways alter blood pressure in animal models. Sequence variants in CYP4A11 and CYP4F2 that produce 20-HETE, UDP-glucuronosyl transferase involved in the biotransformation of 20-HETE and soluble epoxide hydrolase that inactivates EETs are associated with hypertension in human studies. 20-HETE contributes to the regulation of vascular hypertrophy, restenosis, angiogenesis and inflammation. It also promotes endothelial dysfunction and contributes to cerebral vasospasm and ischemia-reperfusion injury in the brain, kidney and heart. This review will focus on the role of 20-HETE in vascular dysfunction, inflammation, ischemic and hemorrhagic stroke and cardiac and renal ischemia reperfusion injury.
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Affiliation(s)
- Fan Fan
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS 39216
| | - Ying Ge
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS 39216
| | - Wenshan Lv
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS 39216 and Department of Endocrinology and Metabolism, the Affiliated Hospital of Qingdao University, Qingdao, China
| | - Matthew R Elliott
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS 39216
| | - Yoshikazu Muroya
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS 39216 and Department of General Medicine and Rehabilitation, Tohoku Medical and Pharmaceutical University School of Medicine, Sendai, Japan
| | - Takashi Hirata
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS 39216 and Taisho Pharmaceutical Co., Ltd., Saitama, Japan
| | - George W Booz
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS 39216
| | - Richard J Roman
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS 39216,
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Dalmasso C, Maranon R, Patil C, Moulana M, Romero DG, Reckelhoff JF. 20-HETE and CYP4A2 ω-hydroxylase contribute to the elevated blood pressure in hyperandrogenemic female rats. Am J Physiol Renal Physiol 2016; 311:F71-7. [PMID: 27194719 DOI: 10.1152/ajprenal.00458.2015] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 05/17/2016] [Indexed: 01/08/2023] Open
Abstract
In male rats, androgen supplements increase 20-hydroxyeicosatetraenoic acid (20-HETE) via cytochrome P-450 (CYP)4A ω-hydroxylase and cause an increase in blood pressure (BP). In the present study, we determined the roles of 20-HETE and CYP4A2 on the elevated BP in hyperandrogenemic female rats. Chronic dihydrotestosterone (DHT) increased mean arterial pressure (MAP) in female Sprague-Dawley rats (96 ± 2 vs. 108 ± 2 mmHg, P < 0.05) and was associated with increased renal microvascular CYP4A2 mRNA expression (15-fold), endogenous renal 20-HETE (5-fold), and ω-hydroxylase activity (3-fold). Chronic DHT also increased MAP in low salt-fed Dahl salt-resistant female rats (81 ± 4 vs. 95 ± 1 mmHg, P < 0.05) but had no effect on MAP in Dahl salt-sensitive female rats (154 ± 3 vs. 153 ± 3 mmHg), which are known to be 20-HETE deficient. To test the role of CYP4A2, female CYP4A2(-/-) and SS.5(Bn) (wild type) rats were treated with DHT. DHT increased MAP in SS.5(Bn) female rats (104 ± 1 vs. 128 ± 1 mmHg, P < 0.05) but had no effect in CYP4A2(-/-) female rats (118 ± 1 vs. 120 ± 1 mmHg). Renal microvascular 20-HETE was reduced in control CYP4A2(-/-) female rats and was increased with DHT in SS.5(Bn) female rats (6-fold) but not CYP4A2(-/-) female rats. ω-Hydroxylase activity was 40% lower in control CYP4A2(-/-) female rats than in SS.5(Bn) female rats, and DHT decreased ω-hydroxylase activity in SS.5(Bn) female rats (by 50%) but significantly increased ω-hydroxylase activity in CYP4A2(-/-) female rats (3-fold). These data suggest that 20-HETE via CYP4A2 contributes to the elevation in BP in hyperandrogenemic female rats. The data also suggest that 20-HETE synthesis inhibition may be effective in treating the elevated BP in women with hyperandrogenemia, such as women with polycystic ovary syndrome.
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Affiliation(s)
- Carolina Dalmasso
- Department of Physiology, University of Mississippi Medical Center, Jackson, Mississippi; Women's Health Research Center, University of Mississippi Medical Center, Jackson, Mississippi
| | - Rodrigo Maranon
- Department of Physiology, University of Mississippi Medical Center, Jackson, Mississippi; Department of Nephrology, University of Mississippi Medical Center, Jackson, Mississippi; Women's Health Research Center, University of Mississippi Medical Center, Jackson, Mississippi
| | - Chetan Patil
- Department of Physiology, University of Mississippi Medical Center, Jackson, Mississippi; Women's Health Research Center, University of Mississippi Medical Center, Jackson, Mississippi
| | - Mohadetheh Moulana
- Department of Psychiatry, University of Mississippi Medical Center, Jackson, Mississippi; Women's Health Research Center, University of Mississippi Medical Center, Jackson, Mississippi
| | - Damian G Romero
- Department of Biochemistry, University of Mississippi Medical Center, Jackson, Mississippi; and Women's Health Research Center, University of Mississippi Medical Center, Jackson, Mississippi
| | - Jane F Reckelhoff
- Department of Physiology, University of Mississippi Medical Center, Jackson, Mississippi; Women's Health Research Center, University of Mississippi Medical Center, Jackson, Mississippi
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29
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Kojima N, Williams JM, Slaughter TN, Kato S, Takahashi T, Miyata N, Roman RJ. Renoprotective effects of combined SGLT2 and ACE inhibitor therapy in diabetic Dahl S rats. Physiol Rep 2015; 3:3/7/e12436. [PMID: 26169541 PMCID: PMC4552522 DOI: 10.14814/phy2.12436] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
This study examined whether control of hyperglycemia with a new SGLT2 inhibitor, luseogliflozin, given alone or in combination with lisinopril could prevent the development of renal injury in diabetic Dahl salt-sensitive (Dahl S) rats treated with streptozotocin (Dahl-STZ). Blood glucose levels increased from normoglycemic to hyperglycemic levels after treatment of STZ in Dahl S rats. Chronic treatment of Dahl-STZ rats with luseogliflozin (10 mg/kg/day) increased the fractional excretion of glucose and normalized blood glucose and HbA1c levels. Lisinopril (20 mg/kg/day) reduced blood pressure from 145 ± 9 to 120 ± 5 mmHg in Dahl-STZ rats, while luseogliflozin had no effect on blood pressure. Combination therapy reduced blood pressure more than that seen in the rats treated with luseogliflozin or lisinopril alone. Dahl-STZ rats exhibited hyperfiltration, mesangial matrix expansion, severe progressive proteinuria, focal glomerulosclerosis and interstitial fibrosis. Control of hyperglycemia with luseogliflozin reduced the degree of hyperfiltration and renal injury but had no effect on blood pressure or the development of proteinuria. Treatment with lisinopril reduced hyperfiltration, proteinuria and renal injury in Dahl-STZ rats. Combination therapy afforded greater renoprotection than administration of either drug alone. These results suggest that long-term control of hyperglycemia with luseogliflozin, especially in combination with lisinopril to lower blood pressure, attenuates the development of renal injury in this rat model of advanced diabetic nephropathy.
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Affiliation(s)
- Naoki Kojima
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi Pharmacology Laboratories, Taisho Pharmaceutical Co., Ltd., Saitama-shi Saitama, Japan
| | - Jan M Williams
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Tiffani N Slaughter
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Sota Kato
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi Pharmacology Laboratories, Taisho Pharmaceutical Co., Ltd., Saitama-shi Saitama, Japan
| | - Teisuke Takahashi
- Pharmacology Laboratories, Taisho Pharmaceutical Co., Ltd., Saitama-shi Saitama, Japan
| | - Noriyuki Miyata
- Pharmaceutical Business Planning, Taisho Pharmaceutical Co., Ltd., Toshima-ku Tokyo, Japan
| | - Richard J Roman
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi
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Layton AT. Recent advances in renal hemodynamics: insights from bench experiments and computer simulations. Am J Physiol Renal Physiol 2015; 308:F951-5. [PMID: 25715984 DOI: 10.1152/ajprenal.00008.2015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 02/23/2015] [Indexed: 01/08/2023] Open
Abstract
It has been long known that the kidney plays an essential role in the control of body fluids and blood pressure and that impairment of renal function may lead to the development of diseases such as hypertension (Guyton AC, Coleman TG, Granger Annu Rev Physiol 34: 13-46, 1972). In this review, we highlight recent advances in our understanding of renal hemodynamics, obtained from experimental and theoretical studies. Some of these studies were published in response to a recent Call for Papers of this journal: Renal Hemodynamics: Integrating with the Nephron and Beyond.
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Affiliation(s)
- Anita T Layton
- Department of Mathematics, Duke University, Durham, North Carolina
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Abstract
Intrarenal autoregulatory mechanisms maintain renal blood flow (RBF) and glomerular filtration rate (GFR) independent of renal perfusion pressure (RPP) over a defined range (80-180 mmHg). Such autoregulation is mediated largely by the myogenic and the macula densa-tubuloglomerular feedback (MD-TGF) responses that regulate preglomerular vasomotor tone primarily of the afferent arteriole. Differences in response times allow separation of these mechanisms in the time and frequency domains. Mechanotransduction initiating the myogenic response requires a sensing mechanism activated by stretch of vascular smooth muscle cells (VSMCs) and coupled to intracellular signaling pathways eliciting plasma membrane depolarization and a rise in cytosolic free calcium concentration ([Ca(2+)]i). Proposed mechanosensors include epithelial sodium channels (ENaC), integrins, and/or transient receptor potential (TRP) channels. Increased [Ca(2+)]i occurs predominantly by Ca(2+) influx through L-type voltage-operated Ca(2+) channels (VOCC). Increased [Ca(2+)]i activates inositol trisphosphate receptors (IP3R) and ryanodine receptors (RyR) to mobilize Ca(2+) from sarcoplasmic reticular stores. Myogenic vasoconstriction is sustained by increased Ca(2+) sensitivity, mediated by protein kinase C and Rho/Rho-kinase that favors a positive balance between myosin light-chain kinase and phosphatase. Increased RPP activates MD-TGF by transducing a signal of epithelial MD salt reabsorption to adjust afferent arteriolar vasoconstriction. A combination of vascular and tubular mechanisms, novel to the kidney, provides for high autoregulatory efficiency that maintains RBF and GFR, stabilizes sodium excretion, and buffers transmission of RPP to sensitive glomerular capillaries, thereby protecting against hypertensive barotrauma. A unique aspect of the myogenic response in the renal vasculature is modulation of its strength and speed by the MD-TGF and by a connecting tubule glomerular feedback (CT-GF) mechanism. Reactive oxygen species and nitric oxide are modulators of myogenic and MD-TGF mechanisms. Attenuated renal autoregulation contributes to renal damage in many, but not all, models of renal, diabetic, and hypertensive diseases. This review provides a summary of our current knowledge regarding underlying mechanisms enabling renal autoregulation in health and disease and methods used for its study.
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Affiliation(s)
- Mattias Carlström
- Department of Medicine, Division of Nephrology and Hypertension and Hypertension, Kidney and Vascular Research Center, Georgetown University, Washington, District of Columbia; Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; and Department of Cell Biology and Physiology, UNC Kidney Center, and McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Christopher S Wilcox
- Department of Medicine, Division of Nephrology and Hypertension and Hypertension, Kidney and Vascular Research Center, Georgetown University, Washington, District of Columbia; Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; and Department of Cell Biology and Physiology, UNC Kidney Center, and McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - William J Arendshorst
- Department of Medicine, Division of Nephrology and Hypertension and Hypertension, Kidney and Vascular Research Center, Georgetown University, Washington, District of Columbia; Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; and Department of Cell Biology and Physiology, UNC Kidney Center, and McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
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Abstract
PURPOSE OF REVIEW Cytochrome (CYP) P450 metabolites of arachidonic acid, 20-hydroxyeicosatetraenoic acid (20-HETE) and epoxyeicosatrienoic acids (EETs) contribute to the regulation of renal tubular and vascular function. This review highlights the results of the recent genetic studies in humans and rodent models, indicating that these eicosanoids participate in the control of blood pressure (BP), chronic kidney disease (CKD), renal ischemia-reperfusion injury (IRI) and polycystic kidney disease (PKD). RECENT FINDINGS Endogenous 20-HETE has been reported to play an essential role in the myogenic and tubuloglomerular feedback responses in the afferent arteriole, and a deficiency of 20-HETE contributes to the development of hypertension and renal injury in Dahl S rats. Mutations in CYP4A11 and CYP4F2 have been linked to elevated BP in humans. EETs have been shown to regulate epithelial sodium channel in the collecting duct, lower BP and have renoprotective properties. 20-HETE also opposes the development of CKD and IRI, and may play a role in PKD. SUMMARY These studies indicate that CYP P450 metabolites of arachidonic acid play an important role in the control of BP, CKD, AKI and PKD. Drugs targeting these pathways could be useful in the treatment of IRI and CKD.
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Affiliation(s)
- Fan Fan
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi, USA
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