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Kim J, Lee SY, Lee J, Yoon S, Kim EG, Lee E, Kim N, Lee S, Gym H, Park SI. Effects of uric acid on ischemic diseases, stratified by lipid levels: a drug-target, nonlinear Mendelian randomization study. Sci Rep 2024; 14:1338. [PMID: 38228698 PMCID: PMC10791707 DOI: 10.1038/s41598-024-51724-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Accepted: 01/09/2024] [Indexed: 01/18/2024] Open
Abstract
Although uric acid-lowering agents such as xanthine oxidase inhibitors have potential cardioprotective effects, studies on their use in preventing cardiovascular diseases are lacking. We investigated the genetically proxied effects of reducing uric acid on ischemic cardiovascular diseases in a lipid-level-stratified population. We performed drug-target Mendelian randomization (MR) analyses using UK Biobank data to select genetic instruments within a uric acid-lowering gene, xanthine dehydrogenase (XDH), and construct genetic scores. For nonlinear MR analyses, individuals were stratified by lipid level. Outcomes included acute myocardial infarction (AMI), ischemic heart disease, cerebral infarction, transient cerebral ischemic attack, overall ischemic disease, and gout. We included 474,983 non-gout individuals with XDH-associated single-nucleotide polymorphisms. The XDH-variant-induced uric acid reduction was associated with reduced risk of gout (odds ratio [OR], 0.85; 95% confidence interval [CI], 0.78-0.93; P < 0.001), cerebral infarction (OR, 0.86; 95% CI, 0.75-0.98; P = 0.023), AMI (OR, 0.79; 95% CI, 0.66-0.94; P = 0.010) in individuals with triglycerides ≥ 188.00 mg/dL, and cerebral infarction in individuals with low-density lipoprotein cholesterol (LDL-C) ≤ 112.30 mg/dL (OR, 0.76; 95% CI, 0.61-0.96; P = 0.020) or LDL-C of 136.90-157.40 mg/dL (OR, 0.67; 95% CI, 0.49-0.92; P = 0.012). XDH-variant-induced uric acid reduction lowers the risk of gout, AMI for individuals with high triglycerides, and cerebral infarction except for individuals with high LDL-C, highlighting the potential heterogeneity in the protective effects of xanthine oxidase inhibitors for treating AMI and cerebral infarction depending on the lipid profiles.
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Affiliation(s)
- Jungeun Kim
- Basgenbio Inc., Seoul, Republic of Korea
- Department of Statistics and Actuarial Science, College of Natural Sciences, Soongsil University, Seoul, Republic of Korea
| | | | - Jihye Lee
- Basgenbio Inc., Seoul, Republic of Korea
| | - Sanghyuk Yoon
- Basgenbio Inc., Seoul, Republic of Korea
- Department of Epidemiology and Health Promotion, Graduate School of Public Health, Yonsei University, Seoul, Republic of Korea
| | | | | | - Nayoung Kim
- Basgenbio Inc., Seoul, Republic of Korea
- Department of Epidemiology and Health Promotion, Graduate School of Public Health, Yonsei University, Seoul, Republic of Korea
| | - Sol Lee
- Basgenbio Inc., Seoul, Republic of Korea
| | - Ho Gym
- Basgenbio Inc., Seoul, Republic of Korea
| | - Sang-In Park
- Department of Pharmacology, College of Medicine, Kangwon National University, 1 Gangwondaehak-gil, Chuncheon-si, Gangwon-do, 24341, Republic of Korea.
- Biomedical Research Institute, Kangwon National University Hospital, Chuncheon, Republic of Korea.
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Ai X, Huang H, Miao Z, Zhou T, Wu H, Lai Y. Relationship between xanthine oxidase gene polymorphisms and anti-tuberculosis drug-induced liver injury in a Chinese population. Infect Genet Evol 2021; 93:104991. [PMID: 34229066 DOI: 10.1016/j.meegid.2021.104991] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 06/16/2021] [Accepted: 07/01/2021] [Indexed: 12/23/2022]
Abstract
This study was designed to investigate the association of the xanthine oxidase (XO) polymorphisms and susceptibility to anti-tuberculosis drug-induced liver injury (ATDILI) in Chinese population. A total of 183 tuberculosis patients were enrolled. Patients with ATDILI were classified as cases and those without ATDILI were classified as controls. Genotyping for XO polymorphisms was determined by polymerase chain reaction and direct sequencing. The allele frequencies and genotype distribution was analyzed using the Chi square test to analyze the association between the gene polymorphisms and ATDILI. Binary logistic regression analysis was performed to assess the risk factors of ATDILI. A total of 21 patients were developed liver injury during anti-tuberculosis treatment in this study, with an incidence of 11.48%. In genotype analysis, no significant difference was observed in the alleles and genotypes frequencies of the six SNPs between two groups (P > 0.05). In haplotype analysis, carriers with GGGATA (rs1884725- rs2295475 -rs45523133- rs206812- rs206813- rs7575607) haplotype had a significantly higher risk of ATDILI compared with other haplotypes (OR = 2.445, 95%CI: 1.058-5.652, P < 0.05). This study suggested that the haplotype GGGATA constructed with rs206812 and rs7575607 mutant alleles might contribute to ATDILI susceptibility in a Chinese population.
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Affiliation(s)
- Xin Ai
- Department of Pharmacology, College of Pharmacy, Dali University, 32 Jia Shi Bo Ave, Dali 671000, Yunnan, People's Republic of China
| | - Hangxing Huang
- Department of Pharmacology, College of Pharmacy, Dali University, 32 Jia Shi Bo Ave, Dali 671000, Yunnan, People's Republic of China
| | - Zhimin Miao
- Department of Pharmacology, College of Pharmacy, Dali University, 32 Jia Shi Bo Ave, Dali 671000, Yunnan, People's Republic of China
| | - Tao Zhou
- Department of Pharmacology, College of Pharmacy, Dali University, 32 Jia Shi Bo Ave, Dali 671000, Yunnan, People's Republic of China
| | - He Wu
- Department of Pharmacology, College of Pharmacy, Dali University, 32 Jia Shi Bo Ave, Dali 671000, Yunnan, People's Republic of China
| | - Yong Lai
- Department of Pharmacology, College of Pharmacy, Dali University, 32 Jia Shi Bo Ave, Dali 671000, Yunnan, People's Republic of China..
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Schmidt HM, Wood KC, Lewis SE, Hahn SA, Williams XM, McMahon B, Baust JJ, Yuan S, Bachman TN, Wang Y, Oh JY, Ghosh S, Ofori-Acquah SF, Lebensburger JD, Patel RP, Du J, Vitturi DA, Kelley EE, Straub AC. Xanthine Oxidase Drives Hemolysis and Vascular Malfunction in Sickle Cell Disease. Arterioscler Thromb Vasc Biol 2021; 41:769-782. [PMID: 33267657 PMCID: PMC8185582 DOI: 10.1161/atvbaha.120.315081] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
OBJECTIVE Chronic hemolysis is a hallmark of sickle cell disease (SCD) and a driver of vasculopathy; however, the mechanisms contributing to hemolysis remain incompletely understood. Although XO (xanthine oxidase) activity has been shown to be elevated in SCD, its role remains unknown. XO binds endothelium and generates oxidants as a byproduct of hypoxanthine and xanthine catabolism. We hypothesized that XO inhibition decreases oxidant production leading to less hemolysis. Approach and Results: Wild-type mice were bone marrow transplanted with control (AA) or sickle (SS) Townes bone marrow. After 12 weeks, mice were treated with 10 mg/kg per day of febuxostat (Uloric), Food and Drug Administration-approved XO inhibitor, for 10 weeks. Hematologic analysis demonstrated increased hematocrit, cellular hemoglobin, and red blood cells, with no change in reticulocyte percentage. Significant decreases in cell-free hemoglobin and increases in haptoglobin suggest XO inhibition decreased hemolysis. Myographic studies demonstrated improved pulmonary vascular dilation and blunted constriction, indicating improved pulmonary vasoreactivity, whereas pulmonary pressure and cardiac function were unaffected. The role of hepatic XO in SCD was evaluated by bone marrow transplanting hepatocyte-specific XO knockout mice with SS Townes bone marrow. However, hepatocyte-specific XO knockout, which results in >50% diminution in circulating XO, did not affect hemolysis levels or vascular function, suggesting hepatocyte-derived elevation of circulating XO is not the driver of hemolysis in SCD. CONCLUSIONS Ten weeks of febuxostat treatment significantly decreased hemolysis and improved pulmonary vasoreactivity in a mouse model of SCD. Although hepatic XO accounts for >50% of circulating XO, it is not the source of XO driving hemolysis in SCD.
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Affiliation(s)
- Heidi M. Schmidt
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Katherine C. Wood
- Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Sara E. Lewis
- Department of Physiology and Pharmacology, Health Sciences Center, West Virginia University, Morgantown, WV
| | - Scott A. Hahn
- Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Xena M. Williams
- Department of Physiology and Pharmacology, Health Sciences Center, West Virginia University, Morgantown, WV
| | - Brenda McMahon
- Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Jeffrey J. Baust
- Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Shuai Yuan
- Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Timothy N. Bachman
- Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Yekai Wang
- Department of Ophthalmology, West Virginia University, Morgantown, WV
- Department of Biochemistry, West Virginia University, Morgantown, WV
| | - Joo-Yeun Oh
- Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL
| | - Samit Ghosh
- Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
- Division of Hematology/Oncology, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, PA
| | - Solomon F. Ofori-Acquah
- Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
- Division of Hematology/Oncology, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, PA
- School of Biomedical and Allied Health Sciences, University of Ghana, Accra, Ghana
| | | | - Rakesh P. Patel
- Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL
| | - Jianhai Du
- Department of Ophthalmology, West Virginia University, Morgantown, WV
- Department of Biochemistry, West Virginia University, Morgantown, WV
| | - Dario A Vitturi
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania
- Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Eric E. Kelley
- Department of Physiology and Pharmacology, Health Sciences Center, West Virginia University, Morgantown, WV
| | - Adam C. Straub
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania
- Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
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Kim YJ, Oh SH, Ahn JS, Yook JM, Kim CD, Park SH, Cho JH, Kim YL. The Crucial Role of Xanthine Oxidase in CKD Progression Associated with Hypercholesterolemia. Int J Mol Sci 2020; 21:ijms21207444. [PMID: 33050202 PMCID: PMC7589966 DOI: 10.3390/ijms21207444] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 09/28/2020] [Accepted: 10/07/2020] [Indexed: 02/08/2023] Open
Abstract
In the present study, we investigated the effects of xanthine oxidase (XO) inhibition on cholesterol-induced renal dysfunction in chronic kidney disease (CKD) mice, and in low-density lipoprotein (LDL)-treated human kidney proximal tubule epithelial (HK-2) cells. ApoE knockout (KO) mice underwent uninephrectomy to induce CKD, and were fed a normal diet or high-cholesterol (HC) diet along with the XO inhibitor topiroxostat (1 mg/kg/day). HK-2 cells were treated with LDL (200 µg/mL) and topiroxostat (5 µM) or small interfering RNA against xanthine dehydrogenase (siXDH; 20 nM). In uninephrectomized ApoE KO mice, the HC diet increased cholesterol accumulation, oxidative stress, XO activity, and kidney damage, while topiroxostat attenuated the hypercholesterolemia-associated renal dysfunction. The HC diet induced cholesterol accumulation by regulating the expressions of genes involved in cholesterol efflux (Nr1h3 and Abca1) and synthesis (Srebf2 and Hmgcr), which was reversed by topiroxostat. Topiroxostat suppressed the expressions of genes related to hypercholesterolemia-associated inflammation and fibrosis in the unilateral kidney. LDL stimulation evoked changes in the cholesterol metabolism, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, and NF-κB pathways in HK-2 cells, which were mitigated by XO inhibition with topiroxostat or siXDH. These findings suggest that XO inhibition exerts renoprotective effects against hypercholesterolemia-associated kidney injury. XO could be a novel therapeutic target for hypercholesterolemia-associated kidney injury in uninephrectomized patients.
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Affiliation(s)
- You-Jin Kim
- Division of Nephrology, Kyungpook National University Hospital, Daegu 41944, Korea; (Y.-J.K.); (S.-H.O.); (J.-S.A.); (J.-M.Y.); (C.-D.K.); (S.-H.P.)
- Cell and Matrix Research Institute, Kyungpook National University, Daegu 41944, Korea
| | - Se-Hyun Oh
- Division of Nephrology, Kyungpook National University Hospital, Daegu 41944, Korea; (Y.-J.K.); (S.-H.O.); (J.-S.A.); (J.-M.Y.); (C.-D.K.); (S.-H.P.)
- Cell and Matrix Research Institute, Kyungpook National University, Daegu 41944, Korea
| | - Ji-Sun Ahn
- Division of Nephrology, Kyungpook National University Hospital, Daegu 41944, Korea; (Y.-J.K.); (S.-H.O.); (J.-S.A.); (J.-M.Y.); (C.-D.K.); (S.-H.P.)
| | - Ju-Min Yook
- Division of Nephrology, Kyungpook National University Hospital, Daegu 41944, Korea; (Y.-J.K.); (S.-H.O.); (J.-S.A.); (J.-M.Y.); (C.-D.K.); (S.-H.P.)
| | - Chan-Duck Kim
- Division of Nephrology, Kyungpook National University Hospital, Daegu 41944, Korea; (Y.-J.K.); (S.-H.O.); (J.-S.A.); (J.-M.Y.); (C.-D.K.); (S.-H.P.)
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu 41944, Korea
| | - Sun-Hee Park
- Division of Nephrology, Kyungpook National University Hospital, Daegu 41944, Korea; (Y.-J.K.); (S.-H.O.); (J.-S.A.); (J.-M.Y.); (C.-D.K.); (S.-H.P.)
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu 41944, Korea
| | - Jang-Hee Cho
- Division of Nephrology, Kyungpook National University Hospital, Daegu 41944, Korea; (Y.-J.K.); (S.-H.O.); (J.-S.A.); (J.-M.Y.); (C.-D.K.); (S.-H.P.)
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu 41944, Korea
- Correspondence: (J.-H.C.); (Y.-L.K.); Tel.: +82-10-6566-7551(J.-H.C.); +82-53-420-5553 (Y.-L.K.); Fax: +82-53-426-2046 (J.-H.C.); +82-53-423-7583 (Y.-L.K.)
| | - Yong-Lim Kim
- Division of Nephrology, Kyungpook National University Hospital, Daegu 41944, Korea; (Y.-J.K.); (S.-H.O.); (J.-S.A.); (J.-M.Y.); (C.-D.K.); (S.-H.P.)
- Cell and Matrix Research Institute, Kyungpook National University, Daegu 41944, Korea
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu 41944, Korea
- Correspondence: (J.-H.C.); (Y.-L.K.); Tel.: +82-10-6566-7551(J.-H.C.); +82-53-420-5553 (Y.-L.K.); Fax: +82-53-426-2046 (J.-H.C.); +82-53-423-7583 (Y.-L.K.)
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Afify H, Abo-Youssef AM, Abdel-Rahman HM, Allam S, Azouz AA. The modulatory effects of cinnamaldehyde on uric acid level and IL-6/JAK1/STAT3 signaling as a promising therapeutic strategy against benign prostatic hyperplasia. Toxicol Appl Pharmacol 2020; 402:115122. [PMID: 32628957 DOI: 10.1016/j.taap.2020.115122] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 06/11/2020] [Accepted: 06/12/2020] [Indexed: 01/24/2023]
Abstract
Benign prostatic hyperplasia (BPH) is a widespread disorder in elderly men. Cinnamaldehyde, which is a major constituent in the essential oil of cinnamon, has been previously reported to reduce xanthine oxidase activity, in addition to its anti-inflammatory, anti-oxidant, and anti-proliferative activities. Our study was designed to investigate the potential modulatory effects of cinnamaldehyde on testosterone model of BPH in rats through reduction of uric acid level, and suppression of IL-6/JAK1/STAT3 signaling pathway. Cinnamaldehyde (40 and 75 mg/kg) was orally administered to male Wistar rats for 3 weeks, and concurrently with testosterone (3 mg/kg, s.c.) from the second week. Cinnamaldehyde ameliorated the elevation in prostatic weight and index compared to rats treated with testosterone only, that was also confirmed by alleviation of histopathological changes in prostate architecture. The protective mechanisms of cinnamaldehyde were elucidated through inhibition of xanthine oxidase activity and reduced uric acid level. That was accompanied by reduction of the pro-inflammatory cytokines; interleukin-6 (IL-6), IL-1β, tumor necrosis factor-alpha (TNF-α), and the nuclear translocation of the transcription factor NF-κB p65, that could be attributed also to the enhanced anti-oxidant defense by cinnamaldehyde. The protein expression of JAK1, which is IL-6 receptor linked protein, was reduced with subsequently reduced activation of STAT3 protein. That eventually suppressed the formation of the proliferation protein cyclin D1, while elevated Bax/Bcl2 ratio. It can be concluded that reducing uric acid level through xanthine oxidase inhibition and suppression of the inflammatory signaling cascade; IL-6/JAK1/STAT3; by cinnamaldehyde could be a novel and promising therapeutic approach against BPH.
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Affiliation(s)
- Hassan Afify
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Egyptian-Russian University, Cairo, Egypt
| | - Amira M Abo-Youssef
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Beni-Suef University, Beni-Suef, Egypt
| | - Hanaa M Abdel-Rahman
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Egyptian-Russian University, Cairo, Egypt; Department of Forensic Medicine and Toxicology, Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - Shady Allam
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Kafrelsheikh University, Kafrelsheikh, Egypt
| | - Amany A Azouz
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Beni-Suef University, Beni-Suef, Egypt.
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Ristic B, Sivaprakasam S, Narayanan M, Ganapathy V. Hereditary hemochromatosis disrupts uric acid homeostasis and causes hyperuricemia via altered expression/activity of xanthine oxidase and ABCG2. Biochem J 2020; 477:1499-1513. [PMID: 32239172 PMCID: PMC7200644 DOI: 10.1042/bcj20190873] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 03/30/2020] [Accepted: 04/01/2020] [Indexed: 12/20/2022]
Abstract
Hereditary hemochromatosis (HH) is mostly caused by mutations in the iron-regulatory gene HFE. The disease is associated with iron overload, resulting in liver cirrhosis/cancer, cardiomegaly, kidney dysfunction, diabetes, and arthritis. Fe2+-induced oxidative damage is suspected in the etiology of these symptoms. Here we examined, using Hfe-/- mice, whether disruption of uric acid (UA) homeostasis plays any role in HH-associated arthritis. We detected elevated levels of UA in serum and intestine in Hfe-/- mice compared with controls. Though the expression of xanthine oxidase, which generates UA, was not different in liver and intestine between wild type and Hfe-/- mice, the enzymatic activity was higher in Hfe-/- mice. We then examined various transporters involved in UA absorption/excretion. Glut9 expression did not change; however, there was an increase in Mrp4 and a decrease in Abcg2 in Hfe-/- mice. As ABCG2 mediates intestinal excretion of UA and mutations in ABCG2 cause hyperuricemia, we examined the potential connection between iron and ABCG2. We found p53-responsive elements in hABCG2 promoter and confirmed with chromatin immunoprecipitation that p53 binds to this promoter. p53 protein was reduced in Hfe-/- mouse intestine. p53 is a heme-binding protein and p53-heme complex is subjected to proteasomal degradation. We conclude that iron/heme overload in HH increases xanthine oxidase activity and also promotes p53 degradation resulting in decreased ABCG2 expression. As a result, systemic UA production is increased and intestinal excretion of UA via ABCG2 is decreased, causing serum and tissue accumulation of UA, a potential factor in the etiology of HH-associated arthritis.
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Affiliation(s)
- Bojana Ristic
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, U.S.A
| | - Sathish Sivaprakasam
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, U.S.A
| | - Monisha Narayanan
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, U.S.A
| | - Vadivel Ganapathy
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, U.S.A
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Kulshrestha R, Singh H, Pandey A, Soundarya D, Jaggi AS, Ravi K. Differential expression of caveolin-1 during pathogenesis of combined pulmonary fibrosis and emphysema: Effect of phosphodiesterase-5 inhibitor. Biochim Biophys Acta Mol Basis Dis 2020; 1866:165802. [PMID: 32311453 DOI: 10.1016/j.bbadis.2020.165802] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 03/20/2020] [Accepted: 04/13/2020] [Indexed: 12/15/2022]
Abstract
INTRODUCTION Combined pulmonary fibrosis and emphysema (CPFE) is a relatively new entity within the spectrum of cigarette smoke induced lung disorders. Currently there is no consensus about its treatment. We hypothesized that caveolin-1 critically determines the parenchymal and vascular remodeling leading to the development of CPFE. We assessed the effect of therapeutic targeting of caveolin-1 in mesenchymal and endothelial cells by the phosphodiesterase-5 inhibitor, sildenafil. METHODS Male Wistar rats (n = 168) were exposed to; room air (control); bleomycin (7 U/kg), bleomycin+sildenafil (50 mg/kg/day P.O.), cigarette smoke (CS) (4 Gold Flake 69 mm/day), CS + sildenafil, CS + bleomycin, CS + bleomycin+sildenafil. Animals were euthanized at 8, 9, 11, 12 weeks and lung histopathological changes, collagen deposition, ROS, Xanthine oxidase, caveolin-1 determined. RESULTS Cigarette smoke causes progressive ROS accumulation, caveolin-1 up-regulation in alveolar epithelial cells, alveolar macrophages, peribronchiolar fibroblasts, endothelial and vascular smooth muscle cells, interstitial inflammation and emphysema. Sildenafil reduces oxidative stress, parenchymal caveolin-1 and attenuates emphysema caused by CS. Bleomycin increases lung ROS and downregulates caveolin-1 leading to fibroblast proliferation and fibrosis. Combined cigarette smoke and bleomycin exposure, results in differential caveolin-1 expression and heterogeneous parenchymal remodeling with alternating areas of emphysema and fibrosis. Increased caveolin-1 induces premature senescence of lung fibroblasts and emphysema. Decreased caveolin-1 is associated with propagation of EMT and fibrosis. Sildenafil attenuates the parenchymal remodeling however it is not effective in reducing VSMC hypertrophy in combined group. CONCLUSION CPFE is characterized by heterogenous parenchymal remodeling and differential caveolin-1 expression. Sildenafil therapy attenuates parenchymal pathologies in CPFE. Additional therapy is however needed for attenuating VSMC remodeling.
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Affiliation(s)
- R Kulshrestha
- Department of Pathology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India.
| | - H Singh
- Department of Pathology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
| | - A Pandey
- Department of Pathology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
| | - D Soundarya
- Department of Pathology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
| | - A S Jaggi
- Dept of Pharmaceutical Sciences and Drug Research, Punjabi University, Patiala, India
| | - K Ravi
- Department of Physiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
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Huang W, Hutabarat RP, Chai Z, Zheng T, Zhang W, Li D. Antioxidant Blueberry Anthocyanins Induce Vasodilation via PI3K/Akt Signaling Pathway in High-Glucose-Induced Human Umbilical Vein Endothelial Cells. Int J Mol Sci 2020; 21:E1575. [PMID: 32106617 PMCID: PMC7084611 DOI: 10.3390/ijms21051575] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 02/17/2020] [Accepted: 02/21/2020] [Indexed: 01/02/2023] Open
Abstract
Blueberries are rich in antioxidant anthocyanins. The hypotensive effects of blueberry anthocyanins in endothelial cells was investigated here. Pretreatment with blueberry anthocyanin extract, malvidin, malvidin-3-glucoside, and malvidin-3-galactoside significantly ameliorated high-glucose-induced damage by enhancing endogenous antioxidant superoxide dismutase (SOD) and heme oxygenase-1 (HO-1), lowering reactive oxygen species (ROS) generation and NADPH oxidase isoform 4 (NOX4) expression, and increasing the cell vitalities. They also effectively induced a vasodilatory effect by increasing the vasodilator nitric oxide (NO) and its promoters endothelial NO synthase (eNOS) and peroxisome proliferator-activated receptor-γ (PPARγ) levels as well as by decreasing the vasoconstrictor angiotensin-converting enzyme (ACE), xanthine oxidase-1 (XO-1), and low-density lipoprotein (LDL) levels. The activation of phosphoinositide 3-kinase (PI3K)/Akt signaling pathway and the breakdown of protein kinase C zeta (PKCζ) pathway were involved in the bioactivities. The results indicated blueberry anthocyanins protected endothelial function against high-glucose (HG) injury via antioxidant and vasodilatory mechanisms, which could be promising molecules as a hypotensive nutraceutical for diabetes patients.
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Affiliation(s)
- Wuyang Huang
- Institute of Agro-Product Processing & Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China; (W.H.); (R.P.H.); (Z.C.)
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China
| | - Ruth Paulina Hutabarat
- Institute of Agro-Product Processing & Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China; (W.H.); (R.P.H.); (Z.C.)
- Department of Food Science and Nutrition, Jinling College, Nanjing Normal University, Nanjing 210097, China;
| | - Zhi Chai
- Institute of Agro-Product Processing & Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China; (W.H.); (R.P.H.); (Z.C.)
| | - Tiesong Zheng
- Department of Food Science and Nutrition, Jinling College, Nanjing Normal University, Nanjing 210097, China;
| | - Weimin Zhang
- College of Food Science, Hainan University, Hainan 570228, China
| | - Dajing Li
- Institute of Agro-Product Processing & Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China; (W.H.); (R.P.H.); (Z.C.)
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9
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Lee YS, Sung YY, Yuk HJ, Son E, Lee S, Kim JS, Kim DS. Anti-hyperuricemic effect of Alpinia oxyphylla seed extract by enhancing uric acid excretion in the kidney. Phytomedicine 2019; 62:152975. [PMID: 31181404 DOI: 10.1016/j.phymed.2019.152975] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 05/15/2019] [Accepted: 05/30/2019] [Indexed: 06/09/2023]
Abstract
BACKGROUND Alpinia oxyphylla is a well-known traditional medicine used in China and Korea to treat intestinal disorders, urosis, diuresis, and chronic glomerulonephritis. PURPOSE We investigated the anti-hyperuricemic effects of Alpinia oxyphylla seed extract (AE), and the underlying mechanisms of action through in vitro and in vivo studies. METHODS We evaluated levels of uric acid in the serum and urine, the expression of renal urate transport proteins, and levels of inflammatory cytokines in potassium oxonate (PO)-induced hyperuricemic rats. Xanthine oxidase activity was analyzed in vitro, while cellular uric acid uptake was assessed in oocytes expressing the human urate transporter 1 (hURAT1). Moreover, the main components of AE were analyzed using UPLC. RESULTS In PO-induced hyperuricemic rats, 200 and 400 mg/kg of AE significantly decreased levels of uric acid in serum, while 400 mg/kg of AE increased uric acid levels in urine. AE did not inhibit xanthine oxidase in vitro; however, 1, 10, and 100 μg/ml of AE significantly decreased uric acid uptake into oocytes expressing hURAT1. Furthermore, 400 mg/kg of AE increased levels of organic anion transporter (OAT) 1 protein, while 200 and 400 mg/kg of AE decreased the protein content of urate transporter, URAT1 and inflammatory cytokines in the kidneys. Nootkatone was identified as one the main chemical components in AE from UPLC analysis. CONCLUSIONS These findings suggest that AE exerts anti-hyperuricemic and uricosuric effects, which are related to the promotion of uric acid excretion via enhanced secretion and inhibition of uric acid reabsorption in the kidneys. Thus, AE may be a potential treatment for hyperuricemia and gout.
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Affiliation(s)
- Young-Sil Lee
- Herbal Medicine Research Division, Korea Institute of Oriental Medicine, 1672 Yuseong-daero, Yuseong-gu, Dajeon 34054, Republic of Korea
| | - Yoon-Young Sung
- Herbal Medicine Research Division, Korea Institute of Oriental Medicine, 1672 Yuseong-daero, Yuseong-gu, Dajeon 34054, Republic of Korea
| | - Heung Joo Yuk
- Herbal Medicine Research Division, Korea Institute of Oriental Medicine, 1672 Yuseong-daero, Yuseong-gu, Dajeon 34054, Republic of Korea
| | - Eunjung Son
- Herbal Medicine Research Division, Korea Institute of Oriental Medicine, 1672 Yuseong-daero, Yuseong-gu, Dajeon 34054, Republic of Korea
| | - SeonJoo Lee
- R&D Research innovation Team, Kwangdong Pharm Co., Ltd. 271, Digital-ro, Guro-gu, Seoul 08387, Republic of Korea
| | - Jin Soo Kim
- R&D Research innovation Team, Kwangdong Pharm Co., Ltd. 271, Digital-ro, Guro-gu, Seoul 08387, Republic of Korea
| | - Dong-Seon Kim
- Herbal Medicine Research Division, Korea Institute of Oriental Medicine, 1672 Yuseong-daero, Yuseong-gu, Dajeon 34054, Republic of Korea.
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10
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Xu H, Li C, Mozziconacci O, Zhu R, Xu Y, Tang Y, Chen R, Huang Y, Holzbeierlein JM, Schöneich C, Huang J, Li B. Xanthine oxidase-mediated oxidative stress promotes cancer cell-specific apoptosis. Free Radic Biol Med 2019; 139:70-79. [PMID: 31103463 PMCID: PMC6662189 DOI: 10.1016/j.freeradbiomed.2019.05.019] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 05/06/2019] [Accepted: 05/15/2019] [Indexed: 12/25/2022]
Abstract
The natural compound Alternol was shown to induce profound oxidative stress and apoptotic cell death preferentially in cancer cells. In this study, a comprehensive investigation was conducted to understand the mechanism for Alternol-induced ROS accumulation responsible for apoptotic cell death. Our data revealed that Alternol treatment moderately increased mitochondrial superoxide formation rate, but it was significantly lower than the total ROS positive cell population. Pre-treatment with mitochondria-specific anti-oxidant MitoQ, NOX or NOS specific inhibitors had no protective effect on Alternol-induced ROS accumulation and cell death. However, XDH/XO inhibition by specific small chemical inhibitors or gene silencing reduced total ROS levels and protected cells from apoptosis induced by Alternol. Further analysis revealed that Alternol treatment significantly enhanced XDH oxidative activity and induced a strong protein oxidation-related damage in malignant but not benign cells. Interestingly, benign cells exerted a strong spike in anti-oxidant SOD and catalase activities compared to malignant cells after Alternol treatment. Cell-based protein-ligand engagement and in-silicon docking analysis showed that Alternol interacts with XDH protein on the catalytic domain with two amino acid residues away from its substrate binding sites. Taken together, our data demonstrate that Alternol treatment enhances XDH oxidative activity, leading to ROS-dependent apoptotic cell death.
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Affiliation(s)
- Haixia Xu
- Department of Critical Care Medicine, Renmin Hospital, Wuhan University, Wuhan, China; Department of Urology, The University of Kansas Medical Center, Kansas City, KS, USA
| | - Changlin Li
- Department of Urology, The University of Kansas Medical Center, Kansas City, KS, USA; Institute of Precision Medicine, Jining Medical University, Jining, China
| | - Olivier Mozziconacci
- Department of Pharmaceutical Chemistry, The University of Kansas School of Pharmacy, Lawrence, KS, USA
| | - Runzhi Zhu
- Department of Urology, The University of Kansas Medical Center, Kansas City, KS, USA; Center for Cell Therapy, Department of Medical Oncology, The Affiliated Hospital, Jiangsu University, Zhenjiang, China
| | - Ying Xu
- Department of Urology, The University of Kansas Medical Center, Kansas City, KS, USA
| | - Yuzhe Tang
- Department of Urology, The University of Kansas Medical Center, Kansas City, KS, USA
| | - Ruibao Chen
- Department of Urology, The University of Kansas Medical Center, Kansas City, KS, USA
| | - Yan Huang
- Department of Urology, The University of Kansas Medical Center, Kansas City, KS, USA
| | | | - Christian Schöneich
- Department of Pharmaceutical Chemistry, The University of Kansas School of Pharmacy, Lawrence, KS, USA
| | - Jian Huang
- Department of Pathology, Guangdong Medical University, Zhanjiang, China
| | - Benyi Li
- Department of Urology, The University of Kansas Medical Center, Kansas City, KS, USA; Center for Cell Therapy, Department of Medical Oncology, The Affiliated Hospital, Jiangsu University, Zhenjiang, China; Department of Pathology, Guangdong Medical University, Zhanjiang, China.
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11
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Rizzi E, Amaral JH, Guimarães DA, Conde-Tella SO, Pinheiro LC, Gerlach RF, Castro MM, Tanus-Santos JE. Nitrite treatment downregulates vascular MMP-2 activity and inhibits vascular remodeling in hypertension independently of its antihypertensive effects. Free Radic Biol Med 2019; 130:234-243. [PMID: 30399409 DOI: 10.1016/j.freeradbiomed.2018.11.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2018] [Revised: 10/30/2018] [Accepted: 11/02/2018] [Indexed: 12/12/2022]
Abstract
Hypertension is associated with cardiovascular remodeling. Given that impaired redox state activates matrix metalloproteinase (MMP)- 2 and promotes vascular remodeling, we hypothesized that nitrite treatment at a non-antihypertensive dose exerts antioxidant effects and attenuates both MMP-2 activation and vascular remodeling of hypertension. We examined the effects of oral sodium nitrite at antihypertensive (15 mg/kg) or non-antihypertensive (1 mg/kg) daily dose in hypertensive rats (two kidney, one clip; 2K1C model). Sham-operated and 2K1C hypertensive rats received vehicle or nitrite by gavage for four weeks. Systolic blood pressure decreased only in hypertensive rats treated with nitrite 15 mg/Kg/day. Both low and high nitrite doses decreased 2K1C-induced vascular remodeling assessed by measuring aortic cross-sectional area, media/lumen ratio, and number of vascular smooth muscle cells/aortic length. Both low and high nitrite doses decreased 2K1C-induced vascular oxidative stress assessed in situ with the fluorescent dye DHE and with the lucigenin chemiluminescence assay. Vascular MMP-2 expression and activity were assessed by gel zymography, Western blot, and in situ zymography increased with hypertension. While MMP-2 levels did not change in response to both doses of nitrite, both doses completely prevented hypertension-induced increases in vascular MMP activity. Moreover, incubation of aortas from hypertensive rats with nitrite at 1-20 μmol/L reduced gelatinolytic activity by 20-30%. This effect was fully inhibited by the xanthine oxidase (XOR) inhibitor febuxostat, suggesting XOR-mediated generation of nitric oxide (NO) from nitrite as a mechanism explaining the responses to nitrite. In vitro incubation of aortic extracts with nitrite 20 μmol/L did not affect MMP-2 activity. These results show that nitrite reverses the vascular structural alterations of hypertension, independently of anti-hypertensive effects. This response is mediated, at least in part, by XOR and is attributable to antioxidant effects of nitrite blunting vascular MMP-2 activation. Our findings suggest nitrite therapy to reverse structural alterations of hypertension.
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Affiliation(s)
- Elen Rizzi
- Department of Pharmacology, Ribeirao Preto Medical School, University of Sao Paulo, Av. Bandeirantes, 3900, Ribeirao Preto, SP 14049-900, Brazil; Biotechnology Unit, Ribeirao Preto University, University of Sao Paulo, Av. Bandeirantes, 3900, Ribeirao Preto, SP 14049-900, Brazil
| | - Jefferson H Amaral
- Department of Pharmacology, Ribeirao Preto Medical School, University of Sao Paulo, Av. Bandeirantes, 3900, Ribeirao Preto, SP 14049-900, Brazil
| | - Danielle A Guimarães
- Department of Pharmacology, Ribeirao Preto Medical School, University of Sao Paulo, Av. Bandeirantes, 3900, Ribeirao Preto, SP 14049-900, Brazil
| | - Sandra O Conde-Tella
- Department of Pharmacology, Ribeirao Preto Medical School, University of Sao Paulo, Av. Bandeirantes, 3900, Ribeirao Preto, SP 14049-900, Brazil
| | - Lucas C Pinheiro
- Department of Pharmacology, Ribeirao Preto Medical School, University of Sao Paulo, Av. Bandeirantes, 3900, Ribeirao Preto, SP 14049-900, Brazil
| | - Raquel F Gerlach
- Department of Morphology, Estomatology and Physiology, Dental School of Ribeirao Preto, University of Sao Paulo, Av. Bandeirantes, 3900, Ribeirao Preto, SP 14049-900, Brazil
| | - Michele M Castro
- Department of Pharmacology, Ribeirao Preto Medical School, University of Sao Paulo, Av. Bandeirantes, 3900, Ribeirao Preto, SP 14049-900, Brazil
| | - Jose E Tanus-Santos
- Department of Pharmacology, Ribeirao Preto Medical School, University of Sao Paulo, Av. Bandeirantes, 3900, Ribeirao Preto, SP 14049-900, Brazil.
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12
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Lindsay A, McCourt PM, Karachunski P, Lowe DA, Ervasti JM. Xanthine oxidase is hyper-active in Duchenne muscular dystrophy. Free Radic Biol Med 2018; 129:364-371. [PMID: 30312761 PMCID: PMC6599518 DOI: 10.1016/j.freeradbiomed.2018.10.404] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 09/21/2018] [Accepted: 10/04/2018] [Indexed: 11/30/2022]
Abstract
Generation of superoxide by xanthine oxidase can be stimulated under ischemic and aberrant calcium homeostasis. Because patients and mice with Duchenne muscular dystrophy (DMD) suffer from ischemia and excessive calcium influx, we tested the hypothesis that xanthine oxidase activity is elevated and contributes to disease pathology. Xanthine oxidase activity was measured by urinary isoxanthopterin in DMD patients at rest and in response to exercise. Urinary isoxanthopterin/creatinine was elevated compared to age-matched controls and Becker muscular dystrophy (BMD) patients. Concentrations were also increased after a six minute walk test in ambulatory patients. We also measured urinary isoxanthopterin in wildtype mice and a number of dystrophic mouse models; the DMD mouse model (mdx), mdx mice overexpressing a variety of transgenic miniaturized and chimeric skeletal muscle-specific dystrophins and utrophin and the β-sarcoglycan deficient (Scgb-/-) mouse which represents type 2E human limb-girdle muscular dystrophy. Mdx and Scgb-/-mice had greater urinary isoxanthopterin/creatinine than wildtype mice while mdx mice expressing dystrophin or utrophin linking the extracellular matrix to the actin cytoskeleton were not different than wildtype. We also measured higher levels of urinary ortho-tyrosine in humans and mice deficient for dystrophin to confirm elevated oxidative stress. Surprisingly, mdx had lower xanthine oxidase protein levels and higher mRNA in gastrocnemius muscle compared to wildtype mice, however, the enzymatic activity of skeletal muscle xanthine oxidase was elevated above wildtype and a transgenic rescued mdx mouse (DysΔMTB-mdx). Downhill treadmill running also caused significant increases in mdx urinary isoxanthopterin that was prevented with the xanthine oxidase inhibitor allopurinol. Similarly, in vitro eccentric contraction-induced force drop of mdx muscle was attenuated by the allopurinol metabolite, oxypurinol. Together, our data suggests hyper-activity of xanthine oxidase in DMD, identifies xanthine oxidase activity as a contributing factor in eccentric contraction-induced force drop of dystrophin-deficient skeletal muscle and highlights the potential of isoxanthopterin as a noninvasive biomarker in DMD.
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MESH Headings
- Adolescent
- Allopurinol/pharmacology
- Animals
- Biomarkers/urine
- Case-Control Studies
- Creatinine/urine
- Dystrophin/deficiency
- Dystrophin/genetics
- Enzyme Inhibitors/pharmacology
- Gene Expression Regulation
- Humans
- Male
- Mice
- Mice, Inbred mdx
- Muscle Contraction/drug effects
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/enzymology
- Muscle, Skeletal/physiopathology
- Muscular Dystrophy, Animal/drug therapy
- Muscular Dystrophy, Animal/enzymology
- Muscular Dystrophy, Animal/genetics
- Muscular Dystrophy, Animal/physiopathology
- Muscular Dystrophy, Duchenne/drug therapy
- Muscular Dystrophy, Duchenne/enzymology
- Muscular Dystrophy, Duchenne/genetics
- Muscular Dystrophy, Duchenne/physiopathology
- Oxypurinol/pharmacology
- Sarcoglycans/deficiency
- Sarcoglycans/genetics
- Tyrosine/urine
- Utrophin/deficiency
- Utrophin/genetics
- Xanthine Oxidase/genetics
- Xanthine Oxidase/urine
- Xanthopterin/urine
- Young Adult
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Affiliation(s)
- Angus Lindsay
- Division of Rehabilitation Science and Division of Physical Therapy, Department of Rehabilitation Medicine, University of Minnesota, Minneapolis, USA; Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, USA.
| | - Preston M McCourt
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, USA
| | - Peter Karachunski
- Department of Pediatrics, University of Minnesota, Minneapolis, USA; Department of Neurology, University of Minnesota, Minneapolis, USA
| | - Dawn A Lowe
- Division of Rehabilitation Science and Division of Physical Therapy, Department of Rehabilitation Medicine, University of Minnesota, Minneapolis, USA
| | - James M Ervasti
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, USA
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13
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Abu-Gharbieh E, Shehab NG, Almasri IM, Bustanji Y. Antihyperuricemic and xanthine oxidase inhibitory activities of Tribulus arabicus and its isolated compound, ursolic acid: In vitro and in vivo investigation and docking simulations. PLoS One 2018; 13:e0202572. [PMID: 30114281 PMCID: PMC6095567 DOI: 10.1371/journal.pone.0202572] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 08/06/2018] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Hyperurecemia is usually associated with gout and various metabolic arthritis disorders. Limited medications are available to manage such conditions. This study aimed to isolate the triterpenes constituent of the plant and to assess xanthine oxidase (XO) inhibitory and antihyperuricemic activities of Tribulus arabicus ethanolic extract, its fractions and the isolated compound using in vitro and in vivo approaches. METHODS The ethanolic extract, fractions; n-hexane, chloroform and n-butanol and the isolated compound (ursolic acid) were evaluated in vitro for their XO inhibitory activity. Those that demonstrated significant activity were further evaluated for their antihyperuricemic activity on potassium oxonate-induced hyperuricemia in mice. RESULTS The ethanolic extract was found to be safe up to 5000 mg/kg. The extract and its n-hexane fraction exhibited significant inhibitory activity on XO, whilst only a modest reduction in the enzymatic activity was noticed with n-butanol and chloroform fractions. Furthermore, administration of the ethanolic extract at low and high doses significantly reduced serum urate levels in mice by 31.1 and 64.6% respectively. The isolated active constituent, ursolic acid, showed potent XO inhibition activity (Half maximal inhibitory concentration, IC50 = 10.3 μg/mL), and significantly reduced uric acid level in vivo by 79.9%. Virtually, the binding mode of ursolic acid with XO was determined using molecular docking simulations. CONCLUSIONS The activity of the ethanolic extract of T. arabicus and its n-hexane fraction can be attributed to the isolated compound, ursolic acid. Ursolic acid has good hypouricemic activity and therefore has high potential to be used for the treatment of gout and hyperuricemia-related diseases.
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Affiliation(s)
- Eman Abu-Gharbieh
- Department of Clinical Sciences, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates
- Department of Pharmacology and Toxicology, Dubai Pharmacy College, Dubai, United Arab Emirates
| | - Naglaa G. Shehab
- Department of Pharmaceutical Chemistry and Natural Products, Dubai Pharmacy College, Dubai, United Arab Emirates
- Department of Pharmacognosy, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| | - Ihab M. Almasri
- Department of Pharmaceutical Chemistry and Pharmacognosy, Faculty of Pharmacy, Al Azhar University, Gaza, Palestine
| | - Yasser Bustanji
- Department of Biopharmaceutics and Clinical Pharmacy, Faculty of Pharmacy, The University of Jordan, Amman, Jordan
- Hamdi Mango Center for Scientific Research, The University of Jordan, Amman, Jordan
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14
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Karimi I, Motamedi S, Becker LA. An effort toward molecular neuroeconomics of food deprivation induced food hoarding in mice: focus on xanthine oxidoreductase gene expression and xanthine oxidase activity. Metab Brain Dis 2018; 33:325-331. [PMID: 29260359 DOI: 10.1007/s11011-017-0166-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2016] [Accepted: 12/11/2017] [Indexed: 11/25/2022]
Abstract
The crucial role of xanthine oxidoreductase (XOR) gene and its active isoform, xanthine oxidase (XO), in purine metabolism and cellular oxidative status led us to investigative their fluctuations in food deprivation induced food hoarding in mice. After, 10 h food deprivation, mice that hoarded lesser than 5 g were considered as 'low-hoarders' while mice that hoarded higher than 20 g were considered as 'high-hoarders'. Mice who hoarded between 5 to 20 g of food were excluded from study. An increase (1.133-fold) in encephalic XOR expression has been found in high-hoarders compared with low-hoarders without sex consideration. An increase (~ 50-fold) in encephalic XOR in female high-hoarders vs. female low-hoarders while a decrease (0.026-fold) in encephalic XOR in male high-hoarders vs. male low-hoarders demonstrated that food deprivation is associated with sex-dependent alteration in XOR expression. The encephalic and hepatic XO activities were not different in male high-hoarders vs. male low-hoarders while encephalic XO activity has been also increased significantly in female high-hoarders (~ 4 times) compared to female low-hoarders. The plasma and hepatic XO activities tended to be increased in female high-hoarders as compared to female low-hoarders, however the uric acid levels in plasma, liver and brain tissues were not altered in female high-hoarders as compared to female low-hoarders. In sum, this study generally proposed that different gene expression space is behind of hoarding behavior in a food-deprived mouse model. Specifically, this is the first study that examined the levels of encephalic XO activity and XOR expression in hoarding behavior, although additional studies are requested.
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Affiliation(s)
- Isaac Karimi
- Laboratory of Molecular and Cellular Biology 1214, Department of Basic Veterinary Sciences, School of Veterinary Medicine, Razi University, Kermanshah, Islamic Republic of Iran.
- Department of Biology, Faculty of Science, Razi University, 67149-67346, Daneshgah Street, Tagh-e-Bostan, Kermanshah, Islamic Republic of Iran.
| | - Shima Motamedi
- Laboratory of Molecular and Cellular Biology 1214, Department of Basic Veterinary Sciences, School of Veterinary Medicine, Razi University, Kermanshah, Islamic Republic of Iran
| | - Lora A Becker
- Department of Psychology, University of Evansville, Evansville, IN, 47722, USA
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15
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Barquissau V, Capel F, Dardevet D, Feillet-Coudray C, Gallinier A, Chauvin MA, Rieusset J, Morio B. Reactive oxygen species enhance mitochondrial function, insulin sensitivity and glucose uptake in skeletal muscle of senescence accelerated prone mice SAMP8. Free Radic Biol Med 2017; 113:267-279. [PMID: 29024807 DOI: 10.1016/j.freeradbiomed.2017.10.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 09/12/2017] [Accepted: 10/07/2017] [Indexed: 10/18/2022]
Abstract
Whereas reactive oxygen species (ROS) can have opposite impacts on insulin signaling, they have mainly been associated with mitochondrial dysfunction in skeletal muscle. We analyzed the relationship between these three features in skeletal muscle of senescence accelerated mice (SAM) prone (P8), which are characterized by enhanced oxidative stress compared to SAM resistant (R1). Oxidative stress, ROS production, antioxidant system, mitochondrial content and functioning, as well as in vitro and in vivo insulin signaling were investigated in gastrocnemius and quadriceps muscles. In SAMP8 compared to SAMR1, muscle content in carbonylated proteins was two-fold (p < 0.01) and ROS production by xanthine oxidase 70% (p < 0.05) higher. Furthermore, insulin-induced Akt phosphorylation measured in vivo and ex vivo as well as muscle glucose uptake measured ex vivo were significantly higher (p < 0.05). Mitochondrial respiration evidenced uncoupling and higher respiration rates with substrates of complexes II and IV, in agreement with higher maximal activity of complexes II and IV (+ 18% and 62%, respectively, p < 0.05). By contrast, maximal activity of complex I was 22% lower (p < 0.05). All strain differences were corrected after 6 months of N-acetylcysteine (NAC) treatment, thus supporting the involvement of high ROS production in these differences. In conclusion in muscle of SAMP8 compared to SAMR1, high ROS production is associated to higher insulin sensitivity and glucose uptake but to lower mitochondrial complex I activity. These conflicting adaptations, with regards to the resulting imbalance between NADH production and use, were associated with intrinsic adjustments in the mitochondrial respiration chain (mitochondrial uncoupling, enhanced complexes II and IV activity). We propose that these bioenergetics adaptations may help at preserving muscle metabolic flexibility of SAMP8.
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Affiliation(s)
- Valentin Barquissau
- INRA UMR1019 Nutrition Humaine, Laboratoire de Nutrition Humaine, Université d'Auvergne, CRNH, 58 rue Montalembert BP321, 63009 Clermont Ferrand Cedex 1, France
| | - Frédéric Capel
- INRA UMR1019 Nutrition Humaine, Laboratoire de Nutrition Humaine, Université d'Auvergne, CRNH, 58 rue Montalembert BP321, 63009 Clermont Ferrand Cedex 1, France
| | - Dominique Dardevet
- INRA UMR1019 Nutrition Humaine, Laboratoire de Nutrition Humaine, Université d'Auvergne, CRNH, 58 rue Montalembert BP321, 63009 Clermont Ferrand Cedex 1, France
| | | | - Anne Gallinier
- 4STROMALab, Université de Toulouse, CNRS ERL5311, EFS, INP-ENVT, Inserm U1031, UPS, Toulouse, France
| | - Marie-Agnès Chauvin
- INRA UMR1397, Laboratoire CarMeN, Inserm UMR1060, Université Lyon 1, INSA de Lyon, Faculté de Médecine Lyon Sud, BP 12, 165 Chemin du Grand Revoyet, 69921 Oullins Cedex, France
| | - Jennifer Rieusset
- INRA UMR1397, Laboratoire CarMeN, Inserm UMR1060, Université Lyon 1, INSA de Lyon, Faculté de Médecine Lyon Sud, BP 12, 165 Chemin du Grand Revoyet, 69921 Oullins Cedex, France
| | - Béatrice Morio
- INRA UMR1019 Nutrition Humaine, Laboratoire de Nutrition Humaine, Université d'Auvergne, CRNH, 58 rue Montalembert BP321, 63009 Clermont Ferrand Cedex 1, France; INRA UMR1397, Laboratoire CarMeN, Inserm UMR1060, Université Lyon 1, INSA de Lyon, Faculté de Médecine Lyon Sud, BP 12, 165 Chemin du Grand Revoyet, 69921 Oullins Cedex, France.
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16
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Han B, Zhu CX, Shi W, Huang HZ, Hu XG, Zhou XM, Lei M, Li Z. Effect of Rhizoma Polygoni Cuspidati and Ramulus Cinnamomi compatibility on uric acid metabolism and urinary neutrophil gelatinase-associated lipocalin and kidney injury molecule-1 in rats with hyperuricemia. Chin J Integr Med 2017; 23:535-542. [PMID: 28116659 DOI: 10.1007/s11655-016-2649-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To explore the effects of Rhizoma Polygoni Cuspidati and Ramulus Cinnamomi compatibility (PR) on uric acid metabolism and the expression of urinary neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) in rats with hyperuricemia. METHODS Seventy male Sprague Dawley (SD) rats were randomly divided into 7 groups with 10 rats per group, including the normal group, model group, allopurinol group, benzbromarone group and PR groups at 3 doses (3.5, 7, 14 g/kg). Except the normal group, rats of the other groups were intragastrically administered 100 mg/kg hypoxanthine and 250 mg/kg ethambutol, and subcutaneously injected with 200 mg/kg potassium oxonate. All rats were continuously modeled for 17 days, and gavaged with corresponding drugs. The rats of the normal and model groups were gavaged with saline, once a day, for 2 weeks. The levels of serum uric acid (SUA), blood urea nitrogen (BUN) and creatinine (Cr) were determined. In addition, the contents of NGAL and KIM-1 in urine and the mRNA and protein expressions of xanthine oxidase (XOD) in liver of hyperuricemia rats were measured by reverse transcription polymerase chain reaction (RT-PCR) and Western blot, respectively. Moreover, the pathological changes of kidney were analyzed by hematoxylin and eosin (HE) stain method. RESULTS Compared with the normal group, the levels of SUA, BUN, NGAL and KIM-1 and the expressions of hepatic XOD mRNA and protein in the hyperuricemia rats were increased signifificantly (P<0.01). PR signifificantly decreased the levels of SUA, BUN, NGAL and KIM-1 and down-regulated the mRNA and protein expressions of hepatic XOD (P<0.05 or P<0.01). In addition, the pathological changes of kidney were signifificantly suppressed by oral administration of PR. CONCLUSIONS PR ameliorated uric acid metabolism and protected renal function, the underlying mechanism was mediated by decreasing the levels of SUA, BUN, NGAL and KIM-1, inhibiting the expression of hepatic XOD and ameliorating the pathological change of kidney.
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Affiliation(s)
- Bin Han
- College of Traditional Chinese Medicine, Guangdong Pharmaceutical University, Guangzhou, 510006, China
| | - Chun-Xia Zhu
- College of Traditional Chinese Medicine, Guangdong Pharmaceutical University, Guangzhou, 510006, China
| | - Wan Shi
- College of Traditional Chinese Medicine, Guangdong Pharmaceutical University, Guangzhou, 510006, China
| | - Hui-Zhu Huang
- College of Traditional Chinese Medicine, Guangdong Pharmaceutical University, Guangzhou, 510006, China
| | - Xu-Guang Hu
- College of Traditional Chinese Medicine, Guangdong Pharmaceutical University, Guangzhou, 510006, China
| | - Xiao-Ming Zhou
- College of Traditional Chinese Medicine, Guangdong Pharmaceutical University, Guangzhou, 510006, China
| | - Ming Lei
- College of Traditional Chinese Medicine, Guangdong Pharmaceutical University, Guangzhou, 510006, China
| | - Zhong Li
- College of Traditional Chinese Medicine, Guangdong Pharmaceutical University, Guangzhou, 510006, China.
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17
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Zaruma-Torres F, Lares-Asseff I, Reyes-Espinoza A, Loera-Castañeda V, Chairez-Hernández I, Sosa-Macías M, Galaviz-Hernández C, Almanza-Reyes H. Association of ABCB1, ABCC5 and xanthine oxidase genetic polymorphisms with methotrexate adverse reactions in Mexican pediatric patients with ALL. Drug Metab Pers Ther 2016; 30:195-201. [PMID: 26353179 DOI: 10.1515/dmpt-2015-0011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Accepted: 07/14/2015] [Indexed: 01/10/2023]
Abstract
BACKGROUND Acute lymphoblastic leukemia (ALL) is one of the most frequent oncological disorders in pediatric populations. To date, the drug of choice for the treatment of ALL is methotrexate, a drug associated with a high risk of adverse reactions (ADRs). The xanthine oxidase (XO) polymorphisms, 1936A>G and 2107A>G, as well as the polymorphic variants derived from ATP-binding cassette transporter gene subfamilies, ABCB1 and ABCC5, of drug resistant codifying genes, are implicated as precursors of drug-related neurologic, hepatic, and renal toxicities. Our aim was to determine whether the mentioned polymorphisms are risk or protective factors for the development of adverse reactions by methotrexate in our pediatric population with ALL. METHODS A total of 35 Mexican children from Centro Estatal de Cancerología-Durango, Mexico, with ALL and the previously noted polymorphisms as determined qPCR were studied. At the same time, a 12-month drug monitoring program was conducted in accordance with WHO-PAHO guidelines for pharmacovigilance. RESULTS The ABCB11936A>G and 2107A>G and ABCC5 3414+434A>C polymorphisms were not associated with methotrexate ADRs. Single nucleotide polymorphisms (SNPs) of ABCB1 1236C>T (OR 0.19, 95% CI: 0.03-0.9, p<0.05) and ABCC5 3933+313T>C (OR 0.12, 95% CI: 0.027-0.58, p<0.05) were associated with methotrexate ADRs. CONCLUSIONS SNPs 1236C>T of ABCB1 and ABCC5 3933+313T>C are not associated with the development of typical ADRs by methotrexate, rather, they showed a protective factor for myelosuppression in the studied sick population.
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Orriss IR, Arnett TR, George J, Witham MD. Allopurinol and oxypurinol promote osteoblast differentiation and increase bone formation. Exp Cell Res 2016; 342:166-74. [PMID: 26968635 PMCID: PMC4829071 DOI: 10.1016/j.yexcr.2016.03.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 02/29/2016] [Accepted: 03/06/2016] [Indexed: 12/11/2022]
Abstract
Allopurinol and its active metabolite, oxypurinol are widely used in the treatment of gout and hyperuricemia. They inhibit xanthine oxidase (XO) an enzyme in the purine degradation pathway that converts xanthine to uric acid. This investigation examined the effect of allopurinol and oxypurinol on bone formation, cell number and viability, gene expression and enzyme activity in differentiating and mature, bone-forming osteoblasts. Although mRNA expression remained relatively constant, XO activity decreased over time with mature osteoblasts displaying reduced levels of uric acid (20% decrease). Treatment with allopurinol and oxypurinol (0.1-1 µM) reduced XO activity by up to 30%. At these concentrations, allopurinol and oxypurinol increased bone formation by osteoblasts ~4-fold and ~3-fold, respectively. Cell number and viability were unaffected. Both drugs increased tissue non-specific alkaline phosphatase (TNAP) activity up to 65%. Osteocalcin and TNAP mRNA expression was increased, 5-fold and 2-fold, respectively. Expression of NPP1, the enzyme responsible for generating the mineralisation inhibitor, pyrophosphate, was decreased 5-fold. Col1α1 mRNA expression and soluble collagen levels were unchanged. Osteoclast formation and resorptive activity were not affected by treatment with allopurinol or oxypurinol. Our data suggest that inhibition of XO activity promotes osteoblast differentiation, leading to increased bone formation in vitro.
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Affiliation(s)
- Isabel R Orriss
- Department of Comparative Biomedical Sciences, Royal Veterinary College, London NW1 0TU, UK.
| | - Timothy R Arnett
- Department of Cell & Developmental Biology, University College London, London, UK
| | - Jacob George
- Medical Research Institute, University of Dundee, Dundee, UK
| | - Miles D Witham
- Medical Research Institute, University of Dundee, Dundee, UK
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19
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Nishino T, Okamoto K, Kawaguchi Y, Matsumura T, Eger BT, Pai EF, Nishino T. The C-terminal peptide plays a role in the formation of an intermediate form during the transition between xanthine dehydrogenase and xanthine oxidase. FEBS J 2015; 282:3075-90. [PMID: 25817260 PMCID: PMC4832347 DOI: 10.1111/febs.13277] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 03/09/2015] [Accepted: 03/21/2015] [Indexed: 01/24/2023]
Abstract
UNLABELLED Mammalian xanthine oxidoreductase can exist in both dehydrogenase and oxidase forms. Conversion between the two is implicated in such diverse processes as lactation, anti-bacterial activity, reperfusion injury and a growing number of diseases. We have constructed a variant of the rat liver enzyme that lacks the carboxy-terminal amino acids 1316-1331; it appears to assume an intermediate form, exhibiting a mixture of dehydrogenase and oxidase activities. The purified variant protein retained ~ 50-70% of oxidase activity even after prolonged dithiothreitol treatment, supporting a previous prediction that the C-terminal region plays a role in the dehydrogenase to oxidase conversion. In the crystal structure of the protein variant, most of the enzyme stays in an oxidase conformation. After 15 min of incubation with a high concentration of NADH, however, the corresponding X-ray structures showed a dehydrogenase-type conformation. On the other hand, disulfide formation between Cys535 and Cys992, which can clearly be seen in the electron density map of the crystal structure of the variant after removal of dithiothreitol, goes in parallel with the complete conversion to oxidase, resulting in structural changes identical to those observed upon proteolytic cleavage of the linker peptide. These results indicate that the dehydrogenase-oxidase transformation occurs rather readily and the insertion of the C-terminal peptide into the active site cavity of its subunit stabilizes the dehydrogenase form. We propose that the intermediate form can be generated (e.g. in endothelial cells) upon interaction of the C-terminal peptide portion of the enzyme with other proteins or the cell membrane. DATABASE Coordinate sets and structure factors for the four crystal structures reported in the present study have been deposited in the Protein Data Bank under the identification numbers 4YRW, 4YTZ, 4YSW, and 4YTY.
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Affiliation(s)
- Tomoko Nishino
- Department of Biochemistry and Molecular Biology, Nippon Medical School, Tokyo, Japan
| | - Ken Okamoto
- Department of Biochemistry and Molecular Biology, Nippon Medical School, Tokyo, Japan
| | - Yuko Kawaguchi
- Department of Biochemistry and Molecular Biology, Nippon Medical School, Tokyo, Japan
| | - Tomohiro Matsumura
- Department of Biochemistry and Molecular Biology, Nippon Medical School, Tokyo, Japan
| | - Bryan T Eger
- Department of Biochemistry, University of Toronto, ON, Canada
| | - Emil F Pai
- Department of Biochemistry, University of Toronto, ON, Canada
- Departments of Medical Biophysics and Molecular Genetics, University of Toronto, ON, Canada
- Campbell Family Institute for Cancer Research, Ontario Cancer Institute/University Health Network, Toronto, ON, Canada
| | - Takeshi Nishino
- Department of Biochemistry and Molecular Biology, Nippon Medical School, Tokyo, Japan
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Japan
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20
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Zhang YS, Liu B, Luo XJ, Zhang JJ, Li NS, Ma QL, Jiang JL, Li YJ, Li Q, Peng J. A novel function of nuclear nonmuscle myosin regulatory light chain in promotion of xanthine oxidase transcription after myocardial ischemia/reperfusion. Free Radic Biol Med 2015; 83:115-28. [PMID: 25701432 DOI: 10.1016/j.freeradbiomed.2015.02.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2014] [Revised: 02/03/2015] [Accepted: 02/05/2015] [Indexed: 12/12/2022]
Abstract
Nuclear myosin regulates gene transcription and this novel function might be modulated through phosphorylation of the myosin regulatory light chain (p-MLC20). Nonmuscle MLC20 (nmMLC20) is also present in the nuclei of cardiomyocytes and a potential nmMLC20 binding sequence has been identified in the promoter of the xanthine oxidase (XO) gene. Thus, we investigated its function in the regulation of XO transcription after myocardial ischemia/reperfusion (IR). In a rat model of myocardial IR and a cardiomyocyte model of hypoxia/reoxygenation (HR) injury, the cardiac or cell injury, myosin light chain kinase (MLCK) content, XO expression and activity, XO-derived products, and level of nuclear p-nmMLC20 were detected. Coimmunoprecipitation (co-IP), chromatin immunoprecipitation, DNA pull-down, and luciferase reporter gene assays were used to decipher the molecular mechanisms through which nmMLC20 promotes XO expression. IR or HR treatment dramatically elevated nuclear p-nmMLC20 level, accompanied by increased XO expression, activity, and products (H2O2 and uric acid), as well as the IR or HR injury; these effects were ameliorated by inhibition of MLCK or knockdown of nmMLC20. Our findings from these experiments demonstrated that nuclear p-nmMLC20 binds to the consensus sequence GTCGCC in the XO gene promoter, interacts with RNA polymerase II and transcription factor IIB to form a transcription preinitiation complex, and hence activates XO gene transcription. These results suggest that nuclear p-nmMLC20 plays an important role in IR/HR injury by transcriptionally upregulating XO gene expression to increase oxidative stress in myocardium. Our findings demonstrate nuclear nmMLC20 as a potential new therapeutic target to combat cardiac IR injury.
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Affiliation(s)
- Yi-Shuai Zhang
- Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha 410078, China; Hunan Provincial Key Laboratory of Cardiovascular Research, School of Pharmaceutical Sciences, Central South University, Changsha 410078, China
| | - Bin Liu
- Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha 410078, China; Hunan Provincial Key Laboratory of Cardiovascular Research, School of Pharmaceutical Sciences, Central South University, Changsha 410078, China
| | - Xiu-Ju Luo
- Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha 410078, China; Hunan Provincial Key Laboratory of Cardiovascular Research, School of Pharmaceutical Sciences, Central South University, Changsha 410078, China
| | - Jie-Jie Zhang
- Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha 410078, China; Hunan Provincial Key Laboratory of Cardiovascular Research, School of Pharmaceutical Sciences, Central South University, Changsha 410078, China
| | - Nian-Sheng Li
- Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha 410078, China; Hunan Provincial Key Laboratory of Cardiovascular Research, School of Pharmaceutical Sciences, Central South University, Changsha 410078, China
| | - Qi-Lin Ma
- Department of Cardiovascular Medicine, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Jun-Lin Jiang
- Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha 410078, China; Hunan Provincial Key Laboratory of Cardiovascular Research, School of Pharmaceutical Sciences, Central South University, Changsha 410078, China
| | - Yuan-Jian Li
- Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha 410078, China; Hunan Provincial Key Laboratory of Cardiovascular Research, School of Pharmaceutical Sciences, Central South University, Changsha 410078, China
| | - Qingjie Li
- Department of Internal Medicine, The University of Texas Medical Branch, Galveston, TX 77555-1083, USA.
| | - Jun Peng
- Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha 410078, China; Hunan Provincial Key Laboratory of Cardiovascular Research, School of Pharmaceutical Sciences, Central South University, Changsha 410078, China.
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21
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Xu C, Wan X, Xu L, Weng H, Yan M, Miao M, Sun Y, Xu G, Dooley S, Li Y, Yu C. Xanthine oxidase in non-alcoholic fatty liver disease and hyperuricemia: One stone hits two birds. J Hepatol 2015; 62:1412-9. [PMID: 25623823 DOI: 10.1016/j.jhep.2015.01.019] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 11/24/2014] [Accepted: 01/14/2015] [Indexed: 01/18/2023]
Abstract
BACKGROUND & AIMS Hyperuricemia is a common feature of patients with non-alcoholic fatty liver disease (NAFLD). This study aimed to explore the causal relationship and underlying mechanisms between NAFLD and hyperuricemia. METHODS We evaluated the impact of NAFLD on the development of hyperuricemia in a cohort of 5541 baseline hyperuricemia-free individuals. We further analyzed xanthine oxidase (XO), a rate-limiting enzyme that catalyzes uric acid production, as a candidate to link NAFLD and hyperuricemia. RESULTS In the first study, a 7-year prospective analysis found that NAFLD was strongly associated with subsequent development of hyperuricemia. Cox proportional hazards regression analyses showed that age, gender, and body mass index adjusted hazard ratio (95% confidence interval) for incident hyperuricemia was 1.609 (1.129-2.294) in individuals with NAFLD, as compared with those without NAFLD at baseline. In the second study, we observed that expression and activity of XO were significantly increased in cellular and mouse models of NAFLD. Knocking down XO expression or inhibiting XO activity significantly decreases uric acid production and attenuates free fatty acids-induced fat accumulation in HepG2 cells. Inhibiting XO activity also significantly prevents the development of and ameliorates established hepatic steatosis induced by a high-fat diet in mice. Further experiments indicated that XO regulates activation of the NLRP3 inflammasome, which may be essential for the regulatory effect of XO on NAFLD. CONCLUSIONS NAFLD significantly increases the risk of incident hyperuricemia. XO is a mediator of the relationship between NAFLD and hyperuricemia, and may serve as a novel therapeutic target for the two linked diseases.
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Affiliation(s)
- Chengfu Xu
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Xingyong Wan
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Lei Xu
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China; Department of Gastroenterology, Zhejiang University Ningbo Hospital, Ningbo, China
| | - Honglei Weng
- Department of Medicine II, Section Molecular Hepatology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Ming Yan
- Division of Intramural Research, National Institute on Minority Health and Health Disparities, National Institutes of Health, Bethesda, MD, USA; Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Min Miao
- Department of Internal Medicine, Zhenhai Lianhua Hospital, Ningbo, China
| | - Yan Sun
- Division of Intramural Research, National Institute on Minority Health and Health Disparities, National Institutes of Health, Bethesda, MD, USA; Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Genyun Xu
- Department of Laboratory Medicine, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Steven Dooley
- Department of Medicine II, Section Molecular Hepatology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Youming Li
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China.
| | - Chaohui Yu
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China.
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22
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Sinha AK, AbdElgawad H, Giblen T, Zinta G, De Rop M, Asard H, Blust R, De Boeck G. Anti-oxidative defences are modulated differentially in three freshwater teleosts in response to ammonia-induced oxidative stress. PLoS One 2014; 9:e95319. [PMID: 24740135 PMCID: PMC3989309 DOI: 10.1371/journal.pone.0095319] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Accepted: 03/25/2014] [Indexed: 12/19/2022] Open
Abstract
Oxidative stress and the antioxidant response induced by high environmental ammonia (HEA) were investigated in the liver and gills of three freshwater teleosts differing in their sensitivities to ammonia. The highly ammonia-sensitive salmonid Oncorhynchus mykiss (rainbow trout), the less ammonia sensitive cyprinid Cyprinus carpio (common carp) and the highly ammonia-resistant cyprinid Carassius auratus (goldfish) were exposed to 1 mM ammonia (as NH4HCO3) for 0 h (control), 3 h, 12 h, 24 h, 48 h, 84 h and 180 h. Results show that HEA exposure increased ammonia accumulation significantly in the liver of all the three fish species from 24 h–48 h onwards which was associated with an increment in oxidative stress, evidenced by elevation of xanthine oxidase activity and levels of hydrogen peroxide (H2O2) and malondialdehyde (MDA). Unlike in trout, H2O2 and MDA accumulation in carp and goldfish liver was restored to control levels (84 h–180 h); which was accompanied by a concomitant increase in superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase activity and reduced ascorbate content. Many of these defence parameters remained unaffected in trout liver, while components of the glutathione redox cycle (reduced glutathione, glutathione peroxidase and glutathione reductase) enhanced to a greater extent. The present findings suggest that trout rely mainly on glutathione dependent defensive mechanism while carp utilize SOD, CAT and ascorbate as anti-oxidative sentinels. Hepatic cells of goldfish appear to utilize each of these protective systems, and showed more effective anti-oxidative compensatory responses towards HEA than carp, while trout were least effective. The present work also indicates that HEA exposure resulted in a relatively mild oxidative stress in the gills of all three species. This probably explains the almost complete lack of anti-oxidative responses in branchial tissue. This research suggests that oxidative stress, as well as the antioxidant potential clearly differ between salmonid and cyprinid species.
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Affiliation(s)
- Amit Kumar Sinha
- Systemic Physiological and Ecotoxicological Research, Department of Biology, University of Antwerp, Antwerp, Belgium
- * E-mail:
| | - Hamada AbdElgawad
- Molecular Plant Physiology and Biotechnology group, Department of Biology, University of Antwerp, Antwerp, Belgium
| | - Terri Giblen
- Systemic Physiological and Ecotoxicological Research, Department of Biology, University of Antwerp, Antwerp, Belgium
| | - Gaurav Zinta
- Molecular Plant Physiology and Biotechnology group, Department of Biology, University of Antwerp, Antwerp, Belgium
| | - Michelle De Rop
- Systemic Physiological and Ecotoxicological Research, Department of Biology, University of Antwerp, Antwerp, Belgium
| | - Han Asard
- Molecular Plant Physiology and Biotechnology group, Department of Biology, University of Antwerp, Antwerp, Belgium
| | - Ronny Blust
- Systemic Physiological and Ecotoxicological Research, Department of Biology, University of Antwerp, Antwerp, Belgium
| | - Gudrun De Boeck
- Systemic Physiological and Ecotoxicological Research, Department of Biology, University of Antwerp, Antwerp, Belgium
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23
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Barros MP, Hollnagel HC, Glavina AB, Soares CO, Ganini D, Dagenais-Bellefeuille S, Morse D, Colepicolo P. Molybdate:sulfate ratio affects redox metabolism and viability of the dinoflagellate Lingulodinium polyedrum. Aquat Toxicol 2013; 142-143:195-202. [PMID: 24036534 DOI: 10.1016/j.aquatox.2013.08.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Revised: 08/20/2013] [Accepted: 08/21/2013] [Indexed: 06/02/2023]
Abstract
Molybdenum is a transition metal used primarily (90% or more) as an additive to steel and corrosion-resistant alloys in metallurgical industries and its release into the environment is a growing problem. As a catalytic center of some redox enzymes, molybdenum is an essential element for inorganic nitrogen assimilation/fixation, phytohormone synthesis, and free radical metabolism in photosynthesizing species. In oceanic and estuarine waters, microalgae absorb molybdenum as the water-soluble molybdate anion (MoO4(2-)), although MoO4(2-) uptake is thought to compete with uptake of the much more abundant sulfate anion (SO4(2-), approximately 25 mM in seawater). Thus, those aspects of microalgal biology impacted by molybdenum would be better explained by considering both MoO4(2-) and SO4(2-) concentrations in the aquatic milieu. This work examines toxicological, physiological and redox imbalances in the dinoflagellate Lingulodinium polyedrum that have been induced by changes in the molybdate:sulfate ratios. We prepared cultures of Lingulodinium polyedrum grown in artificial seawater containing eight different MoO4(2-) concentrations (from 0 to 200 μM) and three different SO4(2-) concentrations (3.5 mM, 9.6 mM and 25 mM). We measured sulfur content in cells, the activities of the three major antioxidant enzymes (superoxide dismutase, catalase, and ascorbate peroxidase), indexes of oxidative modifications in proteins (carbonyl content) and lipids (thiobarbituric acid-reactive substances, TBARS), the activities of the molybdenum-dependent enzymes xanthine oxidase and nitrate reductase, expression of key protein components of dinoflagellate photosynthesis (peridinin-chlorophyll a protein and ribulose-1,5-biphosphate carboxylase/oxidase) and growth curves. We find evidence for Mo toxicity at relatively high [MoO4(2-)]:[SO4(2-)] ratios. We also find evidence for extensive redox adaptations at Mo levels well below lethal levels.
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Affiliation(s)
- M P Barros
- Postgraduate Program in Health Science (Environmental Chemistry), CBS, Universidade Cruzeiro do Sul, 08060070 São Paulo, SP, Brazil.
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24
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Tabunoki H, Ono H, Ode H, Ishikawa K, Kawana N, Banno Y, Shimada T, Nakamura Y, Yamamoto K, Satoh JI, Bono H. Identification of key uric acid synthesis pathway in a unique mutant silkworm Bombyx mori model of Parkinson's disease. PLoS One 2013; 8:e69130. [PMID: 23894418 PMCID: PMC3722175 DOI: 10.1371/journal.pone.0069130] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Accepted: 06/05/2013] [Indexed: 01/09/2023] Open
Abstract
Plasma uric acid (UA) levels decrease following clinical progression and stage development of Parkinson’s disease (PD). However, the molecular mechanisms underlying decreases in plasma UA levels remain unclear, and the potential to apply mutagenesis to a PD model has not previously been discovered. We identified a unique mutant of the silkworm Bombyx mori (B.mori) op. Initially, we investigated the causality of the phenotypic “op” by microarray analysis using our constructed KAIKO functional annotation pipeline. Consequently, we found a novel UA synthesis-modulating pathway, from DJ-1 to xanthine oxidase, and established methods for large-scale analysis of gene expression in B. mori. We found that the mRNA levels of genes in this pathway were significantly lower in B. mori op mutants, indicating that downstream events in the signal transduction cascade might be prevented. Additionally, levels of B.mori tyrosine hydroxylase (TH) and DJ-1 mRNA were significantly lower in the brain of B. mori op mutants. UA content was significantly lower in the B. mori op mutant tissues and hemolymph. The possibility that the B. mori op mutant might be due to loss of DJ-1 function was supported by the observed vulnerability to oxidative stress. These results suggest that UA synthesis, transport, elimination and accumulation are decreased by environmental oxidative stress in the B. mori op mutant. In the case of B. mori op mutants, the relatively low availability of UA appears to be due both to the oxidation of DJ-1 and to its expenditure to mitigate the effects of environmental oxidative stress. Our findings are expected to provide information needed to elucidate the molecular mechanism of decreased plasma UA levels in the clinical stage progression of PD.
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Affiliation(s)
- Hiroko Tabunoki
- Department of Bioinformatics and Molecular Neuropathology, Meiji Pharmaceutical University, Tokyo, Japan
- * E-mail: (HT); (HB)
| | - Hiromasa Ono
- Database Center for Life Science (DBCLS), Research Organization of Information and Systems (ROIS), Tokyo, Japan
| | - Hiroaki Ode
- Department of Bioinformatics and Molecular Neuropathology, Meiji Pharmaceutical University, Tokyo, Japan
| | - Kazuhiro Ishikawa
- Department of Bioinformatics and Molecular Neuropathology, Meiji Pharmaceutical University, Tokyo, Japan
| | - Natsuki Kawana
- Department of Bioinformatics and Molecular Neuropathology, Meiji Pharmaceutical University, Tokyo, Japan
| | - Yutaka Banno
- The Center of Genetic Resources, Kyushu University, Fukuoka, Japan
| | - Toru Shimada
- Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Yuki Nakamura
- Insect Genome Research Unit, National Institute of Agrobiological Sciences, Tsukuba, Japan
| | - Kimiko Yamamoto
- Insect Genome Research Unit, National Institute of Agrobiological Sciences, Tsukuba, Japan
| | - Jun-ichi Satoh
- Department of Bioinformatics and Molecular Neuropathology, Meiji Pharmaceutical University, Tokyo, Japan
| | - Hidemasa Bono
- Database Center for Life Science (DBCLS), Research Organization of Information and Systems (ROIS), Tokyo, Japan
- * E-mail: (HT); (HB)
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25
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Kumar S, Prasad S, Sitasawad SL. Multiple antioxidants improve cardiac complications and inhibit cardiac cell death in streptozotocin-induced diabetic rats. PLoS One 2013; 8:e67009. [PMID: 23843977 PMCID: PMC3699585 DOI: 10.1371/journal.pone.0067009] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2012] [Accepted: 05/17/2013] [Indexed: 12/21/2022] Open
Abstract
Diabetic cardiomyopathy, a disorder of the heart muscle in diabetic patients, is one of the major causes of heart failure. Since diabetic cardiomyopathy is now known to have a high prevalence in the asymptomatic diabetic patient, prevention at the earliest stage of development by existing molecules would be appropriate in order to prevent the progression of heart failure. In this study, we investigated the protective role of multiple antioxidants (MA), on cardiac dysfunction and cardiac cell apoptosis in streptozotocin (STZ)-induced diabetic rat. Diabetic cardiomyopathy in STZ-treated animals was characterized by declined systolic, diastolic myocardial performance, oxidative stress and apoptosis in cardiac cells. Diabetic rats on supplementation with MA showed decreased oxidative stress evaluated by the content of reduced levels of lipid per-oxidation and decreased activity of catalase with down-regulation of heme-oxygenase-1 mRNA. Supplementation with MA also resulted in a normalized lipid profile and decreased levels of pro-inflammatory transcription factor NF-kappaB as well as cytokines such as TNF-α, IFN-γ, TGF-β, and IL-10. MA was found to decrease the expression of ROS-generating enzymes like xanthine oxidase, monoamine oxidase-A along with 5-Lipoxygenase mRNA and/or protein expression. Further, left ventricular function, measured by a microtip pressure transducer, was re-established as evidenced by increase in ±dp/dtmax, heart rate, decreased blood pressure, systolic and diastolic pressure as well as decrease in the TUNEL positive cardiac cells with increased Bcl-2/Bax ratio. In addition, MA supplementation decreased cell death and activation of NF-kappaB in cardiac H9c2 cells. Based on our results, we conclude that MA supplementation significantly attenuated cardiac dysfunction in diabetic rats; hence MA supplementation may have important clinical implications in terms of prevention and management of diabetic cardiomyopathy.
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Affiliation(s)
- Santosh Kumar
- National Centre for Cell Science, NCCS Complex, Ganeshkhind, Pune, India
| | - Sahdeo Prasad
- National Centre for Cell Science, NCCS Complex, Ganeshkhind, Pune, India
| | - Sandhya L. Sitasawad
- National Centre for Cell Science, NCCS Complex, Ganeshkhind, Pune, India
- * E-mail:
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Kennedy MJ, Abdel-Rahman SM, Kashuba ADM, Leeder JS. Comparison of Various Urine Collection Intervals for Caffeine and Dextromethorphan Phenotyping in Children. J Clin Pharmacol 2013; 44:708-14. [PMID: 15199075 DOI: 10.1177/0091270004266624] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Caffeine and dextromethorphan have been used successfully both alone and in combination to assess phenotype and enzyme activity in children of various ages. Previous pediatric phenotyping studies with these agents have used varying durations of urine collection. However, the minimum duration required for accurate phenotypic assessment with these compounds in children remains unknown. We calculated the cumulative metabolite recoveries and molar ratios in urine collected from children for 2, 4, 6, and 8 hours after caffeine and dextromethorphan administration to determine when respective urinary molar ratios stabilize and thus likely accurately reflect enzyme activity. Subjects (n = 24, ages 3-8 years) were given 4 oz of Coca-Cola(R) ( approximately 11.5 mg caffeine) and a single oral dose of dextromethorphan (0.5 mg/kg). Urine was collected at discrete intervals (0-2, 2-4, 4-6, and 6-8 h) during an 8-hour period, and the cumulative metabolite recoveries and urinary molar ratios were calculated. CYP2D6 genotyping was also performed in 21 of 24 subjects. In CYP2D6 extensive metabolizers, the extent of recovery for relevant metabolites was equivalent by 4 hours and represented 45% to 60% of the total amount recovered in the 8-hour period. The 2-hour CYP1A2 ratio was significantly different from those of longer collection intervals. Metabolite ratios for all other enzymes (i.e., NAT-2, XO, and CYP2D6) were independent of the duration of urine collection. These data suggest that a 4-hour urine collection is adequate for the concurrent assessment of hepatic CYP1A2, NAT-2, XO, and CYP2D6 activity in children ages 3 to 8 years who are CYP2D6 extensive metabolizers, using standard caffeine and dextromethorphan phenotyping methods. Longer collection periods may be required, however, in younger children or CYP2D6 poor metabolizers.
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Affiliation(s)
- Mary Jayne Kennedy
- Division of Pediatric Clinical Pharmacology, The Children's Mercy Hospitals and Clinics, Kansas City, MO, USA
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Liu L, Cui J, Song CJ, Bian JS, Sparatore A, Soldato PD, Wang XY, Yan CD. H(2)S-releasing aspirin protects against aspirin-induced gastric injury via reducing oxidative stress. PLoS One 2012; 7:e46301. [PMID: 23029468 PMCID: PMC3460860 DOI: 10.1371/journal.pone.0046301] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Accepted: 08/29/2012] [Indexed: 12/11/2022] Open
Abstract
The aim of this study was to examine the effect of ACS14, a hydrogen sulfide (H(2)S)-releasing derivative of aspirin (Asp), on Asp-induced gastric injury. Gastric hemorrhagic lesions were induced by intragastric administration of Asp (200 mg/kg, suspended in 0.5% carboxymethyl cellulose solutions) in a volume of 1 ml/100 g body weight. ACS14 (1, 5 or 10 mg/kg) was given 30 min before the Asp administration. The total area of gastric erosions, H(2)S concentration and oxidative stress in gastric tissues were measured three hours after administration of Asp. Treatment with Asp (200 mg/kg), but not ACS14 (430 mg/kg, at equimolar doses to 200 mg/kg Asp), for 3 h significantly increased gastric mucosal injury. The damage caused by Asp was reversed by ACS14 at 1-10 mg/kg in a concentration-dependent manner. ACS14 abrogated Asp-induced upregulation of COX-2 expression, but had no effect on the reduced PGE(2) level. ACS14 reversed the decreased H(2)S concentrations and blood flow in the gastric tissue in Asp-treated rats. Moreover, ACS14 attenuated Asp-suppressed superoxide dismutase-1 (SOD-1) expression and GSH activity, suggesting that ACS14 may stimulate antioxidants in the gastric tissue. ACS14 also obviously inhibited Asp-induced upregulation of protein expression of oxidases including XOD, p47(phox) and p67(phox). In conclusion, ACS14 protects Asp induced gastric mucosal injury by inhibiting oxidative stress in the gastric tissue.
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Affiliation(s)
- Lei Liu
- Department of Physiology, Xuzhou Medical College, Xuzhou, Jiangsu, People’s Republic of China
| | - Jie Cui
- Department of Physiology, Xuzhou Medical College, Xuzhou, Jiangsu, People’s Republic of China
| | - Cheng-Jie Song
- Department of Physiology, Xuzhou Medical College, Xuzhou, Jiangsu, People’s Republic of China
| | - Jin-Song Bian
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Anna Sparatore
- Dipartimento di Scienze Farmaceutiche “Pietro Pratesi,” Università degli Studi di Milano, Milan, Italy
| | | | - Xin-Yu Wang
- Department of Endocrinology, Shenzhen Second People's Hospital, Guangdong Province, People’s Republic of China
- * E-mail: (CDY); (XYW)
| | - Chang-Dong Yan
- Department of Physiology, Xuzhou Medical College, Xuzhou, Jiangsu, People’s Republic of China
- * E-mail: (CDY); (XYW)
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Schuhmacher S, Oelze M, Bollmann F, Kleinert H, Otto C, Heeren T, Steven S, Hausding M, Knorr M, Pautz A, Reifenberg K, Schulz E, Gori T, Wenzel P, Münzel T, Daiber A. Vascular dysfunction in experimental diabetes is improved by pentaerithrityl tetranitrate but not isosorbide-5-mononitrate therapy. Diabetes 2011; 60:2608-16. [PMID: 21844097 PMCID: PMC3178293 DOI: 10.2337/db10-1395] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
OBJECTIVE Diabetes is associated with vascular oxidative stress, activation of NADPH oxidase, and uncoupling of nitric oxide (NO) synthase (endothelial NO synthase [eNOS]). Pentaerithrityl tetranitrate (PETN) is an organic nitrate with potent antioxidant properties via induction of heme oxygenase-1 (HO-1). We tested whether treatment with PETN improves vascular dysfunction in the setting of experimental diabetes. RESEARCH DESIGN AND METHODS After induction of hyperglycemia by streptozotocin (STZ) injection (60 mg/kg i.v.), PETN (15 mg/kg/day p.o.) or isosorbide-5-mononitrate (ISMN; 75 mg/kg/day p.o.) was fed to Wistar rats for 7 weeks. Oxidative stress was assessed by optical methods and oxidative protein modifications, vascular function was determined by isometric tension recordings, protein expression was measured by Western blotting, RNA expression was assessed by quantitative RT-PCR, and HO-1 promoter activity in stable transfected cells was determined by luciferase assays. RESULTS PETN, but not ISMN, improved endothelial dysfunction. NADPH oxidase and serum xanthine oxidase activities were significantly reduced by PETN but not by ISMN. Both organic nitrates had minor effects on the expression of NADPH oxidase subunits, eNOS and dihydrofolate reductase (Western blotting). PETN, but not ISMN, normalized the expression of GTP cyclohydrolase-1, extracellular superoxide dismutase, and S-glutathionylation of eNOS, thereby preventing eNOS uncoupling. The expression of the antioxidant enzyme, HO-1, was increased by STZ treatment and further upregulated by PETN, but not ISMN, via activation of the transcription factor NRF2. CONCLUSIONS In contrast to ISMN, the organic nitrate, PETN, improves endothelial dysfunction in diabetes by preventing eNOS uncoupling and NADPH oxidase activation, thereby reducing oxidative stress. Thus, PETN therapy may be suited to treat patients with cardiovascular complications of diabetes.
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Affiliation(s)
- Swenja Schuhmacher
- 2nd Medical Clinic, Department of Cardiology, Medical Center of the Johannes Gutenberg University, Mainz, Germany
- Center of Thrombosis and Hemostasis, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Matthias Oelze
- 2nd Medical Clinic, Department of Cardiology, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Franziska Bollmann
- Pharmacology Department, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Hartmut Kleinert
- Pharmacology Department, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Christian Otto
- 2nd Medical Clinic, Department of Cardiology, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Tjebo Heeren
- 2nd Medical Clinic, Department of Cardiology, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Sebastian Steven
- 2nd Medical Clinic, Department of Cardiology, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Michael Hausding
- 2nd Medical Clinic, Department of Cardiology, Medical Center of the Johannes Gutenberg University, Mainz, Germany
- Center of Thrombosis and Hemostasis, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Maike Knorr
- 2nd Medical Clinic, Department of Cardiology, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Andrea Pautz
- Pharmacology Department, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Kurt Reifenberg
- Central Laboratory Animal Facility, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Eberhard Schulz
- 2nd Medical Clinic, Department of Cardiology, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Tommaso Gori
- 2nd Medical Clinic, Department of Cardiology, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Philip Wenzel
- 2nd Medical Clinic, Department of Cardiology, Medical Center of the Johannes Gutenberg University, Mainz, Germany
- Center of Thrombosis and Hemostasis, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Thomas Münzel
- 2nd Medical Clinic, Department of Cardiology, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Andreas Daiber
- 2nd Medical Clinic, Department of Cardiology, Medical Center of the Johannes Gutenberg University, Mainz, Germany
- Corresponding author: Andreas Daiber,
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Stiburkova B, Krijt J, Vyletal P, Bartl J, Gerhatova E, Korinek M, Sebesta I. Novel mutations in xanthine dehydrogenase/oxidase cause severe hypouricemia: biochemical and molecular genetic analysis in two Czech families with xanthinuria type I. Clin Chim Acta 2011; 413:93-9. [PMID: 21963464 DOI: 10.1016/j.cca.2011.08.038] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Revised: 08/29/2011] [Accepted: 08/30/2011] [Indexed: 02/04/2023]
Abstract
BACKGROUND The article describes the clinical, biochemical, enzymological and molecular genetics findings in two patients from two families with xanthinuria type I. METHODS Biochemical analysis using high performance liquid chromatography, allopurinol loading test and analysis of xanthine oxidase activity in plasma and of uromodulin excretion in urine were performed. Sequencing analysis of the xanthine dehydrogenase gene and the haplotype and statistical analyses of consanguinity were performed. RESULTS Probands showed extremely low concentrations of uric acid, on seven occasions under the limit of detection. The concentration of uric acid in 38-year-old female was 15 μmol/L in serum and 0.04 mmol/L in urine. Excretion of xanthine in urine was 170 mmol/mol creatinine. The concentration of uric acid in 25-year-old male was 0.03 mmol/L in urine. Excretion of xanthine in urine was 141 mmol/mol creatinine. The allopurinol loading test confirmed xanthinuria type I. The xanthine oxidase activities in patients were 0 and 0.4 pmol/h/mL of plasma. We found three nonsense changes: p.P214QfsX4 and unpublished p.R825X and p.R881X. CONCLUSIONS We found two nonconsanguineous compound heterozygotes with xanthinuria type I caused by three nonsense changes. The methods used did not confirm consanguinity in the probands, thus there might be an unconfirmed biological relationship or mutational hotspot.
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Affiliation(s)
- Blanka Stiburkova
- Institute of Inherited Metabolic Disorders, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Prague, Czech Republic.
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Papapostolou I, Georgiou CD. Superoxide radical is involved in the sclerotial differentiation of filamentous phytopathogenic fungi: identification of a fungal xanthine oxidase. Fungal Biol 2010; 114:387-95. [PMID: 20943149 DOI: 10.1016/j.funbio.2010.01.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2009] [Revised: 12/13/2009] [Accepted: 01/31/2010] [Indexed: 11/19/2022]
Abstract
This study shows that the direct indicator of oxidative stress superoxide radical (O·₂⁻) is involved in the sclerotial differentiation of the phytopathogenic filamentous fungi Rhizoctonia solani, Sclerotinia sclerotiorum, Sclerotium rolfsii, and Sclerotinia minor. The production rate of O·₂⁻ and the antioxidant enzyme superoxide dismutase (SOD) levels in the sclerotiogenic fungi were significantly higher and lower, respectively, than those of their non-differentiating counterpart strains, which strongly suggests that the oxidative stress of the sclerotium differentiating fungi is higher than that of the non-differentiating ones. Xanthine oxidase (XO), which was detected for the first time in fungi in general, was localized in the cytoplasmic membrane. The contribution of XO in the overall O·₂⁻production was very significant, reaching 30-70% among the strains, especially in the transition developmental stage between the undifferentiated and the differentiated state, suggesting a sclerotium triggering and a phytopathogenic role of XO during plant infection. The additional finding that these fungi secrete extracellular SOD can be related to their protection from the response of plants to produce O·₂⁻ at infection sites.
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Affiliation(s)
- Ioannis Papapostolou
- Department of Biology, Section of Genetics, Cell Biology and Development, University of Patras, 26100 Patras, Greece
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Abstract
A 'null' activity variant for the major liver isozyme of aldehyde oxidase (AOX-1) in adult male mice and an electrophoretically distinct, high activity variant of the second liver isozyme (AOX-2) were used to examine the segregation of the genetic loci encoding these enzymes (Aox-1 and Aox-2 respectively) in breeding studies. A single recombinant between these loci was observed among the 147 backcross progeny examined, which confirms a previous report (Holmes, 1979) for close linkage and genetic distinctness of the two loci. An activity variant for mouse liver xanthine oxidase (XOX) is also reported which behaved as though controlled by codominant alleles at a single locus (designated Xox-1). Genetic analyses showed that the Xox-1 locus segregated independently of the multiple-Aox loci.
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Abstract
1. Twenty-six strains of mice were surveyed by starch gel electrophoresis for genetic variation of four liver enzymes; aldehyde dehydrogenase, aldehyde oxidase, xanthine oxidase and formaldehyde dehydrogenase. 2. A variant of aldehyde dehydrogenase was found in strains ICFW, IS/Cam, NZB, NZW, Simpson and Schneider. A variant of aldehyde oxidase was found in CE. A possible variant of xanthine oxidase was found in SF/Cam. 3. The gene determining the electrophoretic variant of aldehyde oxidase is either the same as, or very closely linked to, the Aox gene which determines aldehyde oxidase activity.
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Recuero M, Vicente MC, Martínez-García A, Ramos MC, Carmona-Saez P, Sastre I, Aldudo J, Vilella E, Frank A, Bullido MJ, Valdivieso F. A free radical-generating system induces the cholesterol biosynthesis pathway: a role in Alzheimer's disease. Aging Cell 2009; 8:128-39. [PMID: 19239419 DOI: 10.1111/j.1474-9726.2009.00457.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Oxidative stress, which plays a critical role in the pathogenesis of neurodegenerative diseases such as Alzheimer's disease (AD), is intimately linked to aging - the best established risk factor for AD. Studies in neuronal cells subjected to oxidative stress, mimicking the situation in AD brains, are therefore of great interest. This paper reports that, in human neuronal cells, oxidative stress induced by the free radical-generating xanthine/xanthine oxidase (X-XOD) system leads to apoptotic cell death. Microarray analyses showed a potent activation of the cholesterol biosynthesis pathway following reductions in the cell cholesterol synthesis caused by the X-XOD treatment; furthermore, the apoptosis was reduced by inhibiting 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) expression with an interfering RNA. The potential importance of this mechanism in AD was investigated by genetic association, and it was found that HMGCR, a key gene in cholesterol metabolism and among those most strongly upregulated, was associated with AD risk. In summary, this work presents a human cell model prepared to mimic the effect of oxidative stress in neurons that might be useful in clarifying the mechanism involved in free radical-induced neurodegeneration. Gene expression analysis followed by genetic association studies indicates a possible link among oxidative stress, cholesterol metabolism and AD.
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Affiliation(s)
- María Recuero
- Departamento de Biología Molecular and Centro de Biología Molecular Severo Ochoa, Cantoblanco, 28049 Madrid, Spain
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Schwarzer C, Fu Z, Fischer H, Machen TE. Redox-independent activation of NF-kappaB by Pseudomonas aeruginosa pyocyanin in a cystic fibrosis airway epithelial cell line. J Biol Chem 2008; 283:27144-53. [PMID: 18682396 PMCID: PMC2555996 DOI: 10.1074/jbc.m709693200] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2007] [Revised: 07/03/2008] [Indexed: 11/06/2022] Open
Abstract
The roles of the Pseudomonas aeruginosa-derived pigment pyocyanin (PYO) as an oxidant and activator of the proinflammatory transcription factor NF-kappaB were tested in a cystic fibrosis (CF) airway epithelial cell line, CF15. 100 microm PYO on its own had no effect or only small effects to activate NF-kappaB (<1.5-fold), but PYO synergized with the TLR5 agonist flagellin. Flagellin activated NF-kappaB 4-20-fold, and PYO increased these activations >2.5-fold. PYO could have synergized with flagellin to activate NF-kappaB by redox cycling with NADPH, generating superoxide (O(2)*), hydrogen peroxide (H(2)O(2)), and hydroxyl radical (HO*). Cytosol-targeted, redox-sensitive roGFP1 and imaging microscopy showed that 1-100 microm PYO oxidized CF15 cytosol redox potential (Psi(cyto)) from -325 mV (control) to -285 mV. O(2)* (derived from KO(2)*. or xanthine + xanthine oxidase) or H(2)O(2) oxidized Psi(cyto) dose-dependently but did not activate NF-kappaB, even in the presence of flagellin, and 400 microm H(2)O(2) inhibited NF-kappaB. Overexpressing intracellular catalase decreased effects of PYO and H(2)O(2) on Psi(cyto) but did not affect flagellin + PYO-activated NF-kappaB. Catalase also reversed the inhibitory effects of H(2)O(2) on NF-kappaB. The HO* scavenger DMSO did not alter the effects of PYO on Psi(cyto) and NF-kappaB. The synergistic NF-kappaB activation was calcium-independent. Thus, in the presence of flagellin, PYO activated NF-kappaB through a redox- and calcium-independent effect.
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Affiliation(s)
- Christian Schwarzer
- Department of Molecular and Cell Biology, University of California, Berkeley, California 94720-3200, USA
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Scragg JL, Dallas ML, Wilkinson JA, Varadi G, Peers C. Carbon monoxide inhibits L-type Ca2+ channels via redox modulation of key cysteine residues by mitochondrial reactive oxygen species. J Biol Chem 2008; 283:24412-9. [PMID: 18596041 PMCID: PMC3259849 DOI: 10.1074/jbc.m803037200] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2008] [Revised: 06/26/2008] [Indexed: 11/06/2022] Open
Abstract
Conditions of stress, such as myocardial infarction, stimulate up-regulation of heme oxygenase (HO-1) to provide cardioprotection. Here, we show that CO, a product of heme catabolism by HO-1, directly inhibits native rat cardiomyocyte L-type Ca2+ currents and the recombinant alpha1C subunit of the human cardiac L-type Ca2+ channel. CO (applied via a recognized CO donor molecule or as the dissolved gas) caused reversible, voltage-independent channel inhibition, which was dependent on the presence of a spliced insert in the cytoplasmic C-terminal region of the channel. Sequential molecular dissection and point mutagenesis identified three key cysteine residues within the proximal 31 amino acids of the splice insert required for CO sensitivity. CO-mediated inhibition was independent of nitric oxide and protein kinase G but was prevented by antioxidants and the reducing agent, dithiothreitol. Inhibition of NADPH oxidase and xanthine oxidase did not affect the inhibitory actions of CO. Instead, inhibitors of complex III (but not complex I) of the mitochondrial electron transport chain and a mitochondrially targeted antioxidant (Mito Q) fully prevented the effects of CO. Our data indicate that the cardioprotective effects of HO-1 activity may be attributable to an inhibitory action of CO on cardiac L-type Ca2+ channels. Inhibition arises from the ability of CO to promote generation of reactive oxygen species from complex III of mitochondria. This in turn leads to redox modulation of any or all of three critical cysteine residues in the channel's cytoplasmic C-terminal tail, resulting in channel inhibition.
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Affiliation(s)
- Jason L. Scragg
- Division of Cardiovascular and Neuronal
Remodelling, Leeds Institute of Genetics, Health, and Therapeutics, Level 10,
Worsley Bldg., University of Leeds, Leeds LS2 9JT, United Kingdom and
RMD Inc., Watertown, Massachusetts 02472
| | - Mark L. Dallas
- Division of Cardiovascular and Neuronal
Remodelling, Leeds Institute of Genetics, Health, and Therapeutics, Level 10,
Worsley Bldg., University of Leeds, Leeds LS2 9JT, United Kingdom and
RMD Inc., Watertown, Massachusetts 02472
| | - Jenny A. Wilkinson
- Division of Cardiovascular and Neuronal
Remodelling, Leeds Institute of Genetics, Health, and Therapeutics, Level 10,
Worsley Bldg., University of Leeds, Leeds LS2 9JT, United Kingdom and
RMD Inc., Watertown, Massachusetts 02472
| | - Gyula Varadi
- Division of Cardiovascular and Neuronal
Remodelling, Leeds Institute of Genetics, Health, and Therapeutics, Level 10,
Worsley Bldg., University of Leeds, Leeds LS2 9JT, United Kingdom and
RMD Inc., Watertown, Massachusetts 02472
| | - Chris Peers
- Division of Cardiovascular and Neuronal
Remodelling, Leeds Institute of Genetics, Health, and Therapeutics, Level 10,
Worsley Bldg., University of Leeds, Leeds LS2 9JT, United Kingdom and
RMD Inc., Watertown, Massachusetts 02472
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Abstract
AIM To investigate the effect and mechanism of morphine on purine nucleotide catabolism. METHODS The rat model of morphine dependence and withdrawal and rat C6 glioma cells in culture were used. Concentrations of uric acid in the plasma were measured by the uricase-rap method, adenosine deaminase (ADA) and xanthine oxidase (XO) in the plasma and tissues were measured by the ADA and XO test kit. RT-PCR and RT-PCR-Southern blotting were used to examine the relative amount of ADA and XO gene transcripts in tissues and C6 cells. RESULTS (i) the concentration of plasma uric acid in the morphine-administered group was significantly higher (P<0.05) than the control group; (ii) during morphine administration and withdrawal periods, the ADA and XO concentrations in the plasma increased significantly (P<0.05); (iii) the amount of ADA and XO in the parietal lobe, liver, small intestine, and skeletal muscles of the morphine-administered groups increased, while the level of ADA and XO in those tissues of the withdrawal groups decreased; (iv) the transcripts of the ADA and XO genes in the parietal lobe, liver, small intestine, and skeletal muscles were higher in the morphine-administered group. The expression of the ADA and XO genes in those tissues returned to the control level during morphine withdrawal, with the exception of the skeletal muscles; and (v) the upregulation of the expression of the ADA and XO genes induced by morphine treatment could be reversed by naloxone. CONCLUSION The effects of morphine on purine nucleotide metabolism might be an important, new biochemical pharmacological mechanism of morphine action.
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Affiliation(s)
- Chang Liu
- Department of Biochemistry and Molecular Biology, Basic Medical School, Jilin University, Jilin, China
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Gusdon AM, Votyakova TV, Reynolds IJ, Mathews CE. Nuclear and Mitochondrial Interaction Involving mt-Nd2 Leads to Increased Mitochondrial Reactive Oxygen Species Production. J Biol Chem 2007; 282:5171-9. [PMID: 17189252 DOI: 10.1074/jbc.m609367200] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
NADH dehydrogenase subunit 2, encoded by the mtDNA, has been associated with resistance to autoimmune type I diabetes (T1D) in a case control study. Recently, we confirmed a role for the mouse ortholog of the protective allele (mt-Nd2(a)) in resistance to T1D using genetic analysis of outcrosses between T1D-resistant ALR and T1D-susceptible NOD mice. We sought to determine the mechanism of disease protection by elucidating whether mt-Nd2(a) affects basal mitochondrial function or mitochondrial function in the presence of oxidative stress. Two lines of reciprocal conplastic mouse strains were generated: one with ALR nuclear DNA and NOD mtDNA (ALR.mt(NOD)) and the reciprocal with NOD nuclear DNA and ALR mtDNA (NOD.mt(ALR)). Basal mitochondrial respiration, transmembrane potential, and electron transport system enzymatic activities showed no difference among the strains. However, ALR.mt(NOD) mitochondria supported by either complex I or complex II substrates produced significantly more reactive oxygen species when compared with both parental strains, NOD.mt(ALR) or C57BL/6 controls. Nitric oxide inhibited respiration to a similar extent for mitochondria from the five strains due to competitive antagonism with molecular oxygen at complex IV. Superoxide and hydrogen peroxide generated by xanthine oxidase did not significantly decrease complex I function. The protein nitrating agents peroxynitrite or nitrogen dioxide radicals significantly decreased complex I function but with no significant difference among the five strains. In summary, mt-Nd2(a) does not confer elevated resistance to oxidative stress; however, it plays a critical role in the control of the mitochondrial reactive oxygen species production.
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Affiliation(s)
- Aaron M Gusdon
- Department of Pediatrics, the University of Pittsburgh School of Medicine and The Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
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Yamaguchi Y, Matsumura T, Ichida K, Okamoto K, Nishino T. Human Xanthine Oxidase Changes its Substrate Specificity to Aldehyde Oxidase Type upon Mutation of Amino Acid Residues in the Active Site: Roles of Active Site Residues in Binding and Activation of Purine Substrate. J Biochem 2007; 141:513-24. [PMID: 17301077 DOI: 10.1093/jb/mvm053] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Xanthine oxidase (oxidoreductase; XOR) and aldehyde oxidase (AO) are similar in protein structure and prosthetic group composition, but differ in substrate preference. Here we show that mutation of two amino acid residues in the active site of human XOR for purine substrates results in conversion of the substrate preference to AO type. Human XOR and its Glu803-to-valine (E803V) and Arg881-to-methionine (R881M) mutants were expressed in an Escherichia coli system. The E803V mutation almost completely abrogated the activity towards hypoxanthine as a substrate, but very weak activity towards xanthine remained. On the other hand, the R881M mutant lacked activity towards xanthine, but retained slight activity towards hypoxanthine. Both mutants, however, exhibited significant aldehyde oxidase activity. The crystal structure of E803V mutant of human XOR was determined at 2.6 A resolution. The overall molybdopterin domain structure of this mutant closely resembles that of bovine milk XOR; amino acid residues in the active centre pocket are situated at very similar positions and in similar orientations, except that Glu803 was replaced by valine, indicating that the decrease in activity towards purine substrate is not due to large conformational change in the mutant enzyme. Unlike wild-type XOR, the mutants were not subject to time-dependent inhibition by allopurinol.
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Affiliation(s)
- Yuichiro Yamaguchi
- Department of Biochemistry and Molecular Biology, Nippon Medical School, 1-1-5 Sendagi, Tokyo, Japan
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Saraiva RM, Minhas KM, Zheng M, Pitz E, Treuer A, Gonzalez D, Schuleri KH, Vandegaer KM, Barouch LA, Hare JM. Reduced neuronal nitric oxide synthase expression contributes to cardiac oxidative stress and nitroso-redox imbalance in ob/ob mice. Nitric Oxide 2006; 16:331-8. [PMID: 17307368 PMCID: PMC2754218 DOI: 10.1016/j.niox.2006.12.001] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2006] [Revised: 11/04/2006] [Accepted: 12/05/2006] [Indexed: 01/12/2023]
Abstract
Disruption of leptin signaling in the heart may contribute to obesity-related cardiac disease, as leptin deficient (oblob) mice display cardiac hypertrophy, increased cardiac apoptosis and reduced survival. Since leptin maintains a tonic level of neuronal nitric oxide synthase (NOS1) expression in the brain, we hypothesized that leptin deficiency would decrease NOS1 cardiac expression, in turn activating xanthine oxidoreductase (XOR) and creating nitroso-redox imbalance. We studied 2- to 6-month-old oblob (n=26) and C57Bl/6 controls (n=27). Cardiac NOS1 protein abundance (P<0.01) and mRNA expression (P=0.03) were reduced in oblob (n=10 and 6, respectively), while NOS3 protein abundance and mRNA expression were unaltered. Importantly, cardiac NOS1 protein abundance was restored towards normal in oblob mice after leptin treatment (n=3; P<0.05 vs leptin untreated oblob mice). NO metabolite (nitrite and nitrate) production within the myocardium was also reduced in oblob mice (n=5; P=0.02). Furthermore, oxidative stress was increased in oblob mice as GSH/GSSG ratio was decreased (n=4; P=0.02). Whereas XOR activity measured by Amplex Red fluorescence was increased (n=8; P=0.04), XOR and NADPH oxidase subunits protein abundance were not changed in oblob mice (n=6). Leptin deficiency did not disrupt NOS1 subcellular localization, as NOS1 co-localized with ryanodine receptor but not with caveolin-3. In conclusion, leptin deficiency is linked to decreased cardiac expression of NOS1 and NO production, with a concomitant increase in XOR activity and oxidative stress, resulting in nitroso-redox imbalance. These data offer novel insights into potential mechanisms of myocardial dysfunction in obesity.
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Affiliation(s)
- Roberto M Saraiva
- Cardiology Division, Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, MD 21205, USA
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40
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Schröder K, Vecchione C, Jung O, Schreiber JG, Shiri-Sverdlov R, van Gorp PJ, Busse R, Brandes RP. Xanthine oxidase inhibitor tungsten prevents the development of atherosclerosis in ApoE knockout mice fed a Western-type diet. Free Radic Biol Med 2006; 41:1353-60. [PMID: 17023262 DOI: 10.1016/j.freeradbiomed.2006.03.026] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2005] [Revised: 03/09/2006] [Accepted: 03/15/2006] [Indexed: 12/12/2022]
Abstract
Hyperlipidemia enhances xanthine oxidase (XO) activity. XO is an important source of reactive oxygen species (ROS). Since ROS are thought to promote atherosclerosis, we hypothesized that XO is involved in the development of atherosclerosis. ApoE(-/-) mice were fed a Western-type (WD) or control diet. In subgroups, tungsten (700 mg/L) was administered to inhibit XO. XO is a secreted enzyme which is formed in the liver as xanthine dehydrogenase (XDH) and binds to the vascular endothelium. High expression of XDH was found in the liver and WD increased liver XDH mRNA and XDH protein expression. WD induced the conversion of XDH to the radical-forming XO. Moreover, WD increased the hepatic expression of CD40, demonstrating activation of hepatic cells. Aortic tissue of ApoE(-/-) mice fed a WD for 6 months exhibited marked atherosclerosis, attenuated endothelium-dependent relaxation to acetylcholine, increased vascular oxidative stress, and mRNA expression of the chemokine KC. Tungsten treatment had no effect on plasma lipids but lowered the plasma XO activity. In animals fed a control diet, tungsten had no effect on radical formation, endothelial function, or atherosclerosis development. In mice fed a WD, however tungsten attenuated the vascular superoxide anion formation, prevented endothelial dysfunction, and attenuated KC mRNA expression. Most importantly, tungsten treatment largely prevented the development of atherosclerosis in the aorta of ApoE(-/-) mice on WD. Therefore, tungsten, potentially via the inhibition of XO, prevents the development of endothelial dysfunction and atherosclerosis in ApoE(-/-) mice on WD.
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Affiliation(s)
- Katrin Schröder
- Institut für Kardiovaskuläre Physiologie, Klinikum der J.W.-Goethe-Universität, Frankfurt am Main, Germany
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41
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Morozov IY, Negrete-Urtasun S, Tilburn J, Jansen CA, Caddick MX, Arst HN. Nonsense-mediated mRNA decay mutation in Aspergillus nidulans. Eukaryot Cell 2006; 5:1838-46. [PMID: 16963627 PMCID: PMC1694799 DOI: 10.1128/ec.00220-06] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
An Aspergillus nidulans mutation, designated nmdA1, has been selected as a partial suppressor of a frameshift mutation and shown to truncate the homologue of the Saccharomyces cerevisiae nonsense-mediated mRNA decay (NMD) surveillance component Nmd2p/Upf2p. nmdA1 elevates steady-state levels of premature termination codon-containing transcripts, as demonstrated using mutations in genes encoding xanthine dehydrogenase (hxA), urate oxidase (uaZ), the transcription factor mediating regulation of gene expression by ambient pH (pacC), and a protease involved in pH signal transduction (palB). nmdA1 can also stabilize pre-mRNA (unspliced) and wild-type transcripts of certain genes. Certain premature termination codon-containing transcripts which escape NMD are relatively stable, a feature more in common with certain nonsense codon-containing mammalian transcripts than with those in S. cerevisiae. As in S. cerevisiae, 5' nonsense codons are more effective at triggering NMD than 3' nonsense codons. Unlike the mammalian situation but in common with S. cerevisiae and other lower eukaryotes, A. nidulans is apparently impervious to the position of premature termination codons with respect to the 3' exon-exon junction.
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Affiliation(s)
- Igor Y Morozov
- Department of Molecular Microbiology and Infection, Flowers Building, Imperial College London, Armstrong Road, London SW7 2AZ, United Kingdom
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42
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Abstract
Aldehyde oxidases are molybdo-flavoenzymes structurally related to xanthine oxidoreductase. They catalyze the oxidation of aldehydes or N-heterocycles of physiological, pharmacological, and toxicological relevance. Rodents are characterized by four aldehyde oxidases as follows: AOX1 and aldehyde oxidase homologs 1-3 (AOH1, AOH2, and AOH3). Humans synthesize a single functional aldehyde oxidase, AOX1. Here we define the structure and the characteristics of the aldehyde oxidase genes and proteins in chicken and dog. The avian genome contains two aldehyde oxidase genes, AOX1 and AOH, mapping to chromosome 7. AOX1 and AOH are structurally very similar and code for proteins whose sequence was deduced from the corresponding cDNAs. AOX1 is the ortholog of the same gene in mammals, whereas AOH represents the likely ancestor of rodent AOH1, AOH2, and AOH3. The dog genome is endowed with two structurally conserved and active aldehyde oxidases clustering on chromosome 37. Cloning of the corresponding cDNAs and tissue distribution studies demonstrate that they are the orthologs of rodent AOH2 and AOH3. The vestiges of dog AOX1 and AOH1 are recognizable upstream of AOH2 and AOH3 on the same chromosome. Comparison of the complement and the structure of the aldehyde oxidase and xanthine oxidoreductase genes in vertebrates and other animal species indicates that they evolved through a series of duplication and inactivation events. Purification of the chicken AOX1 protein to homogeneity from kidney demonstrates that the enzyme possesses retinaldehyde oxidase activity. Unlike humans and most other mammals, dog and chicken are devoid of liver aldehyde oxidase activity.
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Affiliation(s)
- Mineko Terao
- Laboratory of Molecular Biology, Centro Catullo e Daniela Borgomainerio, Istituto di Ricerche Farmacologiche Mario Negri, via Eritrea 62, 20157 Milano, Italy
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Abstract
During chemical hypoxia induced by cobalt chloride (CoCl2), hypoxia-inducible factor 1alpha (HIF1-alpha) mediates the induction of a variety of genes including erythropoietin and vascular endothelial growth factor. We used glioma cells with oxidative phosphorylation-dependent (D54-MG) and glycolytic-dependent (U251-MG) phenotypes to monitor HIF1-alpha regulation in association with redox responsiveness to CoCl2 treatment. We showed that CoCl2 increased xanthine oxidase (XO)-derived reactive oxygen species (ROS), which causes accumulation of HIF1-alpha protein in U251-MG cells. Under these conditions, blockade of XO activity by pharmacologic (N-acetyl-L-cysteine or allopurinol) or molecular (by small interfering RNA) approaches significantly attenuated HIF1-alpha expression. Exogenous H2O2 stabilizes HIF1-alpha protein. XO was present in these cells and was the primary source of free radicals. We also showed higher XO activity in cells exposed to CoCl2 compared with cells grown in normoxia. From the experiments shown here, we concluded that ROS were indeed generated in D54-MG cells exposed to CoCl2 but it was unlikely that ROS participated in the hypoxic signal transduction pathways in this cell type. Possibly, cell type-dependent and stimulus-dependent factors may control ROS dependency or redox sensitivity of HIF1-alpha and thus HIF1-alpha activation either directly or by induction of specific signaling cascades. Our findings reveal that XO-derived ROS is a novel and critical component of HIF1-alpha regulation in U251-MG cells, pointing toward a more general role of this transcription factor in tumor progression.
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Affiliation(s)
- Corinne E Griguer
- Department of Surgery, University of Alabama at Birmingham, Birmingham, Alabama 35294-0005, USA.
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Abstract
The aldehyde oxidase genes (aods) from Methylobacillus sp. KY4400 were cloned, and sequenced. The sequences for small (aodS, 489 bp), medium (aodM, 993 bp), and large (aodL, 2,328 bp) subunit genes were determined. At least one additional ORF was indispensable for the expression of enzyme activity. The structural genes contained two [2Fe-2S] centers, an FAD binding site, and a molybdenum cofactor binding site.
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Affiliation(s)
- Akinori Yasuhara
- BioFrontier Laboratories, Kyowa Hakko Kogyo Co., Ltd., Tokyo, Japan
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Gwinner W, Scheuer H, Haller H, Brandes RP, Groene HJ. Pivotal role of xanthine oxidase in the initiation of tubulointerstitial renal injury in rats with hyperlipidemia. Kidney Int 2006; 69:481-7. [PMID: 16407880 DOI: 10.1038/sj.ki.5000121] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Hyperlipidemia can induce or aggravate renal tubulointerstitial injury. Experiments in a complex rat model with chronic glomerulonephritis and long-standing, coexisting hyperlipidemia suggested that induction of xanthine oxidase (XO), with increased oxygen radical generation, is involved in aggravation of tubulointerstitial injury. To separate the role of XO in the initial events of lipid-mediated tubulointerstitial injury, short-term experiments with diet-induced hyperlipidemia over 21 and 35 days were performed in otherwise healthy rats. XO expression in relation to the antioxidant enzymes was examined in the cortical tubulointerstitium (TIS) and proximal tubules (PT). Subsequent experiments with XO inhibition were performed, examining tubulointerstitial infiltration with ED1-positive cells and expression of adhesion molecules and monocyte chemoattractant protein-1 (MCP-1) as indicators of early injurious events. Hyperlipidemia increased XO activity in TIS by 40 and 86%, and in PT by 28 and 90% at days 21 and 35, compared with controls on regular diet. This increased activity was associated with increased reactive oxygen species. Among the antioxidant enzymes, glutathione peroxidase activity increased in TIS by 40% and in PT by 90%. Histological evaluation showed a three-fold increase in ED1-positive cells and increased MCP-1 and vascular cell adhesion molecule-1 (VCAM-1) expression at day 35 in the TIS. Inhibition of XO prevented tubulointerstitial ED1 cell infiltration, together with a decreased expression of MCP-1 and VCAM-1. These results point to an important role for XO in the early stage of hyperlipidemia-associated renal injury, mediating macrophage infiltration by a putatively redox-dependent upregulation of MCP-1 and VCAM-1.
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Affiliation(s)
- W Gwinner
- Department of Nephrology, Medical School of Hannover, Hannover, Germany.
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Cultrone A, Scazzocchio C, Rochet M, Montero-Morán G, Drevet C, Fernández-Martín R. Convergent evolution of hydroxylation mechanisms in the fungal kingdom: molybdenum cofactor-independent hydroxylation of xanthine via α-ketoglutarate-dependent dioxygenases. Mol Microbiol 2005; 57:276-90. [PMID: 15948966 DOI: 10.1111/j.1365-2958.2005.04686.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The xanthine oxidases and dehydrogenases are among the most conserved enzymes in all living kingdoms. They contain the molybdopterin cofactor Moco. We show here that in the fungi, in addition to xanthine dehydrogenase, a completely different enzyme is able to catalyse the oxidation of xanthine to uric acid. In Aspergillus nidulans this enzyme is coded by the xanA gene. We have cloned the xanA gene and determined its sequence. A deletion of the gene has the same phenotype as the previously known xanA1 miss-sense mutation. Homologues of xanA exist only in the fungal kingdom. We have inactivated the cognate gene of Schizosaccharomyces pombe and this results in strongly impaired xanthine utilization as a nitrogen source. We have shown that the Neurospora crassa homologue is functionally equivalent to xanA. The enzyme coded by xanA is an alpha-ketoglutarate- and Fe(II)-dependent dioxygenase which shares a number of properties with other enzymes of this group. This work shows that only in the fungal kingdom, an alternative mechanism of xanthine oxidation, not involving Moco, has evolved using the dioxygenase scaffold.
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Affiliation(s)
- Antonietta Cultrone
- Institut de Génétique et de Microbiologie, Université Paris-Sud, Bâtiment 409, UMR 8621 CNRS, 91405 Orsay Cedex, France
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Nishino T, Okamoto K, Kawaguchi Y, Hori H, Matsumura T, Eger BT, Pai EF, Nishino T. Mechanism of the conversion of xanthine dehydrogenase to xanthine oxidase: identification of the two cysteine disulfide bonds and crystal structure of a non-convertible rat liver xanthine dehydrogenase mutant. J Biol Chem 2005; 280:24888-94. [PMID: 15878860 DOI: 10.1074/jbc.m501830200] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mammalian xanthine dehydrogenase can be converted to xanthine oxidase by modification of cysteine residues or by proteolysis of the enzyme polypeptide chain. Here we present evidence that the Cys(535) and Cys(992) residues of rat liver enzyme are indeed involved in the rapid conversion from the dehydrogenase to the oxidase. The purified mutants C535A and/or C992R were significantly resistant to conversion by incubation with 4,4'-dithiodipyridine, whereas the recombinant wild-type enzyme converted readily to the oxidase type, indicating that these residues are responsible for the rapid conversion. The C535A/C992R mutant, however, converted very slowly during prolonged incubation with 4,4'-dithiodipyridine, and this slow conversion was blocked by the addition of NADH, suggesting that another cysteine couple located near the NAD(+) binding site is responsible for the slower conversion. On the other hand, the C535A/C992R/C1316S and C535A/C992R/C1324S mutants were completely resistant to conversion, even on prolonged incubation with 4,4'-dithiodipyridine, indicating that Cys(1316) and Cys(1324) are responsible for the slow conversion. The crystal structure of the C535A/C992R/C1324S mutant was determined in its demolybdo form, confirming its dehydrogenase conformation.
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Affiliation(s)
- Tomoko Nishino
- Department of Biochemistry and Molecular Biology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8602, Japan.
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48
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Abstract
Unlike monooxygenases, molybdenum-containing hydroxylases catalyze the hydroxylation of carbon centers using oxygen derived ultimately from water, rather than O(2), as the source of the oxygen atom incorporated into the product, and do not require an external source of reducing equivalents. The mechanism by which this interesting chemistry takes place has been the subject of investigation for some time, and in the last several years the chemical course of the reaction has become increasingly well understood. The present minireview summarizes recent mechanistic and structure/function studies of members of this large and growing family of enzymes.
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Affiliation(s)
- Russ Hille
- Department of Molecular and Cellular Biochemistry, The Ohio State University, 333 Hamilton Hall, 1645 Neil Avenue, Columbus, OH 43210, USA.
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Abstract
Xanthine oxidoreductase (XOR) is the enzyme responsible for the final step in purine degradation resulting in the generation of uric acid. Here we have generated mice deficient in XOR. As expected, these animals lack tissue XOR activity and have low to undetectable serum levels of uric acid. Although normal at birth, XOR-/- mice fail to thrive after 10 to 14 days, and most die within the first month. The cause of death appears to be a form of severe renal dysplasia, a phenotype that closely resembles what has been observed previously in cyclooxygenase-2 (COX-2)-deficient mice. We further demonstrate that in the first month of life, a period in which the mouse kidney is undergoing rapid maturation and remodeling, wild-type mice exhibit an approximately 30-fold increase in renal XOR activity, with a corresponding induction of COX-2 expression. In contrast, during this same period, XOR-/- animals fail to augment renal COX-2 expression. Finally, we show that in vitro and in vivo, uric acid can stimulate basal COX-2 expression. These results demonstrate that XOR activity is an endogenous physiological regulator of COX-2 expression and thereby provide insight into previous epidemiological evidence linking elevated serum uric levels with systemic hypertension and increased mortality from cardiovascular diseases. In addition, these results suggest a novel molecular link between cellular injury and the inflammatory response.
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Affiliation(s)
- Toshio Ohtsubo
- Cardiovascular Branch, National Heart, Lung, and Blood Institute, NIH, Bethesda, Md 20892-1622, USA
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50
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Choi EY, Stockert AL, Leimkühler S, Hille R. Studies on the mechanism of action of xanthine oxidase. J Inorg Biochem 2004; 98:841-8. [PMID: 15134930 DOI: 10.1016/j.jinorgbio.2003.11.010] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2003] [Revised: 11/13/2003] [Accepted: 11/14/2003] [Indexed: 10/26/2022]
Abstract
Recent studies of the reaction mechanism of the molybdenum-containing enzyme xanthine oxidase are presented. The pH-dependence of both the steady-state and rapid reaction kinetics of the enzyme exhibits is bell-shaped, with pK(a)s for the acid and alkaline limbs of 6.6 and 7.4, respectively. These are assigned to ionizations of an active site base and substrate, respectively, with the implication that enzyme acts on the neutral rather than monoanionic form of the purine substrate. A computational study provides evidence that in the course of the reaction tautomerization of substrate occurs, with a proton moving from N-3 to N-9 in the course of the reaction - enzyme facilitation of this tautomerization may contribute as much as 24 kcal/mol in transition state stabilization for the reaction. Electron spin echo (ESEEM) and electron-nuclear double resonance (ENDOR) studies of the so-called "very rapid" Mo(V) intermediate of the reaction, the latter work using a newly synthesized form of the substrate 2-hydroxy-6-methylpurine that has been selectively isotopically labeled at C-8, indicates that product is bound to the molybdenum of the active site in a simple, end-on fashion, consistent with a reaction mechanism involving nucleophilic attack of a (deprotonated) Mo-OH on the C-8 position of substrate. A kinetic study using a series of purines has failed to identify a correlation between the one-electron reduction potential for substrate and catalytic effectiveness, indicating that a reaction mechanism initiated by one-electron, outer-sphere electron transfer is unlikely. Finally, a consideration of the active site structure in the context of the above work suggests specific amino acid residues to target for site-directed mutagenesis studies. Preliminary experiments with two such mutants are entirely consistent with the proposed catalytic roles of two active site glutamate residues.
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Affiliation(s)
- Eun-Young Choi
- Department of Molecular and Cellular Biochemistry, The Ohio State University, 333 Hamilton Hall, 1645 Neil Avenue, Columbus, OH 43210-1218, USA
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