1
|
Sayala J, Srivastava E, Kumar P, Shukla N, Kumar A, Patra AK. Photocytotoxic kinetically stable ruthenium(II)- N, N-donor polypyridyl complexes of oxalate with anticancer activity against HepG2 liver cancer cells. Dalton Trans 2024; 53:4580-4597. [PMID: 38349214 DOI: 10.1039/d3dt04058e] [Citation(s) in RCA: 0] [Impact Index Per Article: 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] [Indexed: 03/06/2024]
Abstract
Liver cancer is one of the leading causes of death that motivating scientists worldwide to synthesize novel chemotherapeutics. Ru(II)-polypyridyl complexes are extensively studied for possible therapeutic and cellular applications due to their tunable coordination chemistry, structural diversity, ligand-exchange kinetics, accessible redox states, and rich photophysical or photochemical properties. Herein, we have synthesized a series of Ru(II) polypyridyl complexes [RuII(N^N)2(ox)] (1-3), where ox is oxalate (C2O42-) and N^N is 1,10-phenanthroline (phen) (1), dipyrido[3,2-d:2',3'-f]quinoxaline (dpq) (2), and dipyrido[3,2,-a:2',3'-c]phenazine (dppz) (3). Oxalate (ox2-) was opted as a bioactive dioxo ligand to prevent facile hydrolysis in aqueous media, thereby increasing the stability of the Ru(II)-polypyridyl complexes in physiological media. We thoroughly characterized all the complexes using ESI-MS, FT-IR, UV-vis, and 1H NMR spectroscopy and other physicochemical methods. The complexes were stable under physiological conditions and under low-energy green LED light (λirr = 530 nm). However, the photoirradiation of complexes resulted in the efficient generation of singlet oxygen (1O2) as a major reactive oxygen species (ROS). The role of the extended aromatic conjugation of the N^N-donor ligands in the complexes was demonstrated by their binding propensities with CT-DNA and bovine serum albumin (BSA). Both DNA intercalation and groove binding were evidenced, while tryptophan (Trp) and tyrosine (Tyr) binding site preferences were revealed from the synchronous fluorescence spectra (SFS) of BSA. The cytotoxic profiling of the complexes performed on hepatocellular carcinoma cells (HepG2) in the dark and in the presence of green light indicated their dose-dependent cytotoxicity. The [RuII(N^N)2(ox)] complexes exhibited enhanced photocytotoxicity mediated by efficient generation of cytotoxic 1O2 and effective interaction with DNA. All the complexes were internalized by the HepG2 liver cancer cells efficiently and localized to the cytoplasm and nucleus. The complexes exhibited potent anti-proliferative, anti-clonogenic, and anti-migratory effects on the cancer cells, suggesting their potential for therapeutic applications.
Collapse
Affiliation(s)
- Juhi Sayala
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh, India.
| | - Ekta Srivastava
- Department of Biological Science & Bioengineering Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh, India
| | - Priyaranjan Kumar
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh, India.
| | - Nitin Shukla
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh, India.
| | - Ashok Kumar
- Department of Biological Science & Bioengineering Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh, India
- Centre for Environmental Science and Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
- Center for Nanosciences, Indian Institute of Technology Kanpur, Kanpur 208016, India
- The Mehta Family Centre for Engineering in Medicine, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Ashis K Patra
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh, India.
| |
Collapse
|
2
|
Chen J, Tang L, Guo W, Wang D, Sun Y, Guo C. Oxalic acid secretion alleviates saline-alkali stress in alfalfa by improving photosynthetic characteristics and antioxidant activity. Plant Physiol Biochem 2024; 208:108475. [PMID: 38430786 DOI: 10.1016/j.plaphy.2024.108475] [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] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 02/19/2024] [Accepted: 02/26/2024] [Indexed: 03/05/2024]
Abstract
Saline-alkali stress significantly affects the growth and yield of alfalfa (Medicago sativa L.). Organic acid secretion is crucial in alleviating abiotic stress-induced damage in plants. In this study, we evaluated the contents of the major organic acids secreted by the roots of tolerant (ZD) and sensitive (LYL) varieties of alfalfa under saline-alkali stress and investigated the effects of these organic acids on the growth, and physiological functions of alfalfa. Our results indicated that the oxalic acid (OA) content was the highest among the organic acids secreted from alfalfa roots under saline-alkali stress, and oxalic acid content was the most significantly different between the two varieties, ZD and LYL, compared to the contents of the other organic acids. Oxalic acid alleviated the inhibition of alfalfa growth caused by saline-alkali stress, improved photosynthetic characteristics, reduced the accumulation of reactive oxygen species, and increased the activity of antioxidant enzymes and content of osmoregulatory substances. Furthermore, oxalic acid resulted in significantly increased expression of genes involved in photosynthesis and antioxidant system in alfalfa under saline-alkali stress. This study revealed the effects of oxalic acid secreted by the root system on stress-related physiological processes, providing valuable insights into the functions of root secretions in plant saline-alkali resistance.
Collapse
Affiliation(s)
- Jiaxin Chen
- Key Laboratory of Molecular and Cytogenetics, College of Life Science and Technology, Harbin Normal University, Harbin, 150025, Heilongjiang Province, China
| | - Lu Tang
- Key Laboratory of Molecular and Cytogenetics, College of Life Science and Technology, Harbin Normal University, Harbin, 150025, Heilongjiang Province, China
| | - Weileng Guo
- Key Laboratory of Molecular and Cytogenetics, College of Life Science and Technology, Harbin Normal University, Harbin, 150025, Heilongjiang Province, China
| | - Dan Wang
- Key Laboratory of Molecular and Cytogenetics, College of Life Science and Technology, Harbin Normal University, Harbin, 150025, Heilongjiang Province, China
| | - Yugang Sun
- Key Laboratory of Molecular and Cytogenetics, College of Life Science and Technology, Harbin Normal University, Harbin, 150025, Heilongjiang Province, China
| | - Changhong Guo
- Key Laboratory of Molecular and Cytogenetics, College of Life Science and Technology, Harbin Normal University, Harbin, 150025, Heilongjiang Province, China.
| |
Collapse
|
3
|
Su X, Song C, He Z, Song Q, Meng L, Dong C, Zhou J, Ke H, Xiong Y, Liu J, Liao W, Yang S. Ambra1 in exosomes secreted by HK-2 cells damaged by supersaturated oxalate induce mitophagy and autophagy-ferroptosis in normal HK-2 cells to participate in the occurrence of kidney stones. Biochim Biophys Acta Mol Cell Res 2024; 1871:119604. [PMID: 37806389 DOI: 10.1016/j.bbamcr.2023.119604] [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] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 09/23/2023] [Accepted: 09/27/2023] [Indexed: 10/10/2023]
Abstract
Injury to the renal tubular epithelium has emerged as a leading factor underlying the formation of kidney stones. Indeed, epithelial cell damage contributes to the adherence and aggregation of crystals, thereby accelerating the formation of renal stones. Meanwhile, exosomes play an instrumental role in cellular communication, including DNA, RNA, mRNA, etc. In this study, homogenous cells were treated with exosomes derived from damaged cells in an attempt to establish "positive feedback" of cell damage, and the desired results were achieved. To begin, a serum-free medium and supersaturated concentrations of oxalate were added to the HK-2 cell line, and then exosomes were isolated from the two groups for analysis and comparison, and the autophagy-related gene Ambra1 (autophagy and beclin-1 regulator 1) was detected. Subsequently, normal HK-2 cells were treated with exosomes, and the related indexes of autophagy, ferroptosis and mitophagy were determined. Thereafter, Ambra1 was knocked down in exosome-derived HK-2 cells, resulting in the down-regulation of Ambra1 expression in exosomes produced by HK-2 cells following oxalate intervention. Thereafter, the ability of exosomes to stimulate autophagy, mitophagy and ferroptosis was re-evaluated in HK-2 cells after Ambra1 knockdown. The results corroborated that exosomes secreted by oxalate-treated HK-2 can directly elevate autophagy, ferroptosis and mitophagy levels in normal cells, and this effect was significantly mitigated following Ambra1 knockdown within exosomes. Meanwhile, exosomes-induced autophagy and ferroptosis were alleviated after knockdown of beclin-1 in recipient HK-2 cells. These results further suggest that beclin-1 plays a critical role in the process of exosome-induced autophagy-ferroptosis.
Collapse
Affiliation(s)
- Xiaozhe Su
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Chao Song
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Ziqi He
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Qianlin Song
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Lingchao Meng
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Caitao Dong
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Jiawei Zhou
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Hu Ke
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Yunhe Xiong
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Junwei Liu
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Wenbiao Liao
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China.
| | - Sixing Yang
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China.
| |
Collapse
|
4
|
Yuan T, Xia Y, Pan S, Li B, Ye Z, Yan X, Hu W, Li L, Song B, Yu W, Li H, Rao T, Lin F, Zhou X, Cheng F. STAT6 promoting oxalate crystal deposition-induced renal fibrosis by mediating macrophage-to-myofibroblast transition via inhibiting fatty acid oxidation. Inflamm Res 2023; 72:2111-2126. [PMID: 37924395 DOI: 10.1007/s00011-023-01803-2] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 09/25/2023] [Accepted: 09/29/2023] [Indexed: 11/06/2023] Open
Abstract
OBJECTIVE AND DESIGN Kidney stones commonly occur with a 50% recurrence rate within 5 years, and can elevate the risk of chronic kidney disease. Macrophage-to-myofibroblast transition (MMT) is a newly discovered mechanism that leads to progressive fibrosis in different forms of kidney disease. In this study, we aimed to investigate the role of MMT in renal fibrosis in glyoxylate-induced kidney stone mice and the mechanism by which signal transducer and activator of transcription 6 (STAT6) regulates MMT. METHODS We collected non-functioning kidneys from patients with stones, established glyoxylate-induced calcium oxalate stone mice model and treated AS1517499 every other day in the treatment group, and constructed a STAT6-knockout RAW264.7 cell line. We first screened the enrichment pathway of the model by transcriptome sequencing; detected renal injury and fibrosis by hematoxylin eosin staining, Von Kossa staining and Sirius red staining; detected MMT levels by multiplexed immunofluorescence and flow cytometry; and verified the binding site of STAT6 at the PPARα promoter by chromatin immunoprecipitation. Fatty acid oxidation (FAO) and fibrosis-related genes were detected by western blot and real-time quantitative polymerase chain reaction. RESULTS In this study, we found that FAO was downregulated, macrophages converted to myofibroblasts, and STAT6 expression was elevated in stone patients and glyoxylate-induced kidney stone mice. The promotion of FAO in macrophages attenuated MMT and upregulated fibrosis-related genes induced by calcium oxalate treatment. Further, inhibition of peroxisome proliferator-activated receptor-α (PPARα) eliminated the effect of STAT6 deletion on FAO and fibrosis-associated protein expression. Pharmacological inhibition of STAT6 also prevented the development of renal injury, lipid accumulation, MMT, and renal fibrosis. Mechanistically, STAT6 transcriptionally represses PPARα and FAO through cis-inducible elements located in the promoter region of the gene, thereby promoting MMT and renal fibrosis. CONCLUSIONS These findings establish a role for STAT6 in kidney stone injury-induced renal fibrosis, and suggest that STAT6 may be a therapeutic target for progressive renal fibrosis in patients with nephrolithiasis.
Collapse
Affiliation(s)
- Tianhui Yuan
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Yuqi Xia
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Shengyu Pan
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Bojun Li
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Zehua Ye
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Xinzhou Yan
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Weimin Hu
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Lei Li
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Baofeng Song
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Weimin Yu
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Haoyong Li
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Ting Rao
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Fangyou Lin
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Xiangjun Zhou
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China.
| | - Fan Cheng
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, China.
| |
Collapse
|
5
|
Ali S, Sattar Khan A, Ullah Malik A, Anwar R, Akbar Anjum M, Nawaz A, Shafique M, Naz S. Combined application of ascorbic and oxalic acids delays postharvest browning of litchi fruits under controlled atmosphere conditions. Food Chem 2021; 350:129277. [PMID: 33618094 DOI: 10.1016/j.foodchem.2021.129277] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [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: 09/17/2020] [Revised: 01/21/2021] [Accepted: 01/29/2021] [Indexed: 11/17/2022]
Abstract
The effect of ascorbic acid [AA (40 mmol L-1)] and oxalic acid [OA (2 mmol L-1)] on browning of litchi fruit was investigated under 5% CO2 + 1% O2 controlled atmosphere (CA) and compared with air at 5 ± 1 °C for 28 days. The combined application of AA and OA suppressed browning index, soluble quinones, and activities of polyphenol oxidase and peroxidase under CA compared with control. The combination of CA along with AA + OA reduced weight loss and maintained higher anthocyanins, total phenolics, membrane integrity, ascorbate peroxidase, catalase, glutathione reductase and superoxide dismutase activities compared with control. In addition, AA + OA + CA combination showed markedly lower malondialdehyde, superoxide anion and hydrogen peroxide with substantially higher soluble solids content, ascorbic acid, titratable acidity and sensory quality compared with control. In conclusion, AA + OA combination could be considered appropriate to delay browning and to conserve litchi fruit visual appearance under CA storage conditions.
Collapse
Affiliation(s)
- Sajid Ali
- Department of Horticulture, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Pakistan
| | - Ahmad Sattar Khan
- Institute of Horticultural Sciences, University of Agriculture, Faisalabad, Pakistan.
| | - Aman Ullah Malik
- Institute of Horticultural Sciences, University of Agriculture, Faisalabad, Pakistan
| | - Raheel Anwar
- Institute of Horticultural Sciences, University of Agriculture, Faisalabad, Pakistan
| | - Muhammad Akbar Anjum
- Department of Horticulture, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Pakistan
| | - Aamir Nawaz
- Department of Horticulture, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Pakistan
| | | | - Safina Naz
- Department of Horticulture, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Pakistan
| |
Collapse
|
6
|
Ding J, Lu G, Nie W, Huang LL, Zhang Y, Fan W, Wu G, Liu H, Xie HY. Self-Activatable Photo-Extracellular Vesicle for Synergistic Trimodal Anticancer Therapy. Adv Mater 2021; 33:e2005562. [PMID: 33432702 DOI: 10.1002/adma.202005562] [Citation(s) in RCA: 71] [Impact Index Per Article: 23.7] [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: 08/16/2020] [Revised: 11/02/2020] [Indexed: 06/12/2023]
Abstract
Extracellular vesicles (EVs) hold great potential in both disease treatment and drug delivery. However, accurate drug release from EVs, as well as the spontaneous treatment effect cooperation of EVs and drugs at target tissues, is still challenging. Here, an engineered self-activatable photo-EV for synergistic trimodal anticancer therapy is reported. M1 macrophage-derived EVs (M1 EVs) are simultaneously loaded with bis[2,4,5-trichloro-6-(pentyloxycarbonyl) phenyl] oxalate (CPPO), chlorin e6 (Ce6), and prodrug aldoxorubicin (Dox-EMCH). After administration, the as-prepared system actively targets tumor cells because of the tumor-homing capability of M1 EVs, wherein M1 EVs repolarize M2 to M1 macrophages, which not only display immunotherapy effects but also produce H2 O2 . The reaction between H2 O2 and CPPO generates chemical energy that activates Ce6, creating both chemiluminescence for imaging and singlet oxygen (1 O2 ) for photodynamic therapy (PDT). Meanwhile, 1 O2 -induced membrane rupture leads to the release of Dox-EMCH, which is then activated and penetrates the deep hypoxic areas of tumors. The synergism of immunotherapy, PDT, and chemotherapy results in potent anticancer efficacy, showing great promise to fight cancers.
Collapse
Affiliation(s)
- Jingjing Ding
- School of Life Science, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Guihong Lu
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Weidong Nie
- School of Life Science, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Li-Li Huang
- School of Life Science, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Yahui Zhang
- School of Life Science, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Wenlin Fan
- School of Life Science, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Guanghao Wu
- School of Life Science, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Houli Liu
- School of Life Science, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Hai-Yan Xie
- School of Life Science, Beijing Institute of Technology, Beijing, 100081, P. R. China
| |
Collapse
|
7
|
Malík I, Csöllei J, Solovič I, Pospíšilová Š, Michnová H, Jampílek J, Čížek A, Kapustíková I, Čurillová J, Pecháčová M, Stolaříková J, Pecher D, Oravec M. Dibasic Derivatives of Phenylcarbamic Acid against Mycobacterial Strains: Old Drugs and New Tricks? Molecules 2018; 23:E2493. [PMID: 30274224 PMCID: PMC6222509 DOI: 10.3390/molecules23102493] [Citation(s) in RCA: 8] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 09/21/2018] [Accepted: 09/24/2018] [Indexed: 12/11/2022] Open
Abstract
In order to provide a more detailed view on the structure⁻antimycobacterial activity relationship (SAR) of phenylcarbamic acid derivatives containing two centers of protonation, 1-[2-[({[2-/3-(alkoxy)phenyl]amino}carbonyl)oxy]-3-(dipropylammonio)propyl]pyrrolidinium oxalates (1a⁻d)/dichlorides (1e⁻h) as well as 1-[2-[({[2-/3-(alkoxy)phenyl]amino}carbonyl)oxy]-3-(di-propylammonio)propyl]azepanium oxalates (1i⁻l)/dichlorides (1m⁻p; alkoxy = butoxy to heptyloxy) were physicochemically characterized by estimation of their surface tension (γ; Traube's stalagmometric method), electronic features (log ε; UV/Vis spectrophotometry) and lipophilic properties (log kw; isocratic RP-HPLC) as well. The experimental log kw dataset was studied together with computational logarithms of partition coefficients (log P) generated by various methods based mainly on atomic or combined atomic and fragmental principles. Similarities and differences between the experimental and in silico lipophilicity descriptors were analyzed by unscaled principal component analysis (PCA). The in vitro activity of compounds 1a⁻p was inspected against Mycobacterium tuberculosis CNCTC My 331/88 (identical with H37Rv and ATCC 2794, respectively), M. tuberculosis H37Ra ATCC 25177, M. kansasii CNCTC My 235/80 (identical with ATCC 12478), the M. kansasii 6509/96 clinical isolate, M. kansasii DSM 44162, M. avium CNCTC My 330/80 (identical with ATCC 25291), M. smegmatis ATCC 700084 and M. marinum CAMP 5644, respectively. In vitro susceptibility of the mycobacteria to reference drugs isoniazid, ethambutol, ofloxacin or ciprofloxacin was tested as well. A very unique aspect of the research was that many compounds from the set 1a⁻p were highly efficient almost against all tested mycobacteria. The most promising derivatives showed MIC values varied from 1.9 μM to 8 μM, which were lower compared to those of used standards, especially if concerning ability to fight M. tuberculosis H37Ra ATCC 25177, M. kansasii DSM 44162 or M. avium CNCTC My 330/80. Current in vitro biological assays and systematic SAR studies based on PCA approach as well as fitting procedures, which were supported by relevant statistical descriptors, proved that the compounds 1a⁻p represented a very promising molecular framework for development of 'non-traditional' but effective antimycobacterial agents.
Collapse
Affiliation(s)
- Ivan Malík
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, SK-832 32 Bratislava, Slovakia.
| | - Jozef Csöllei
- Department of Chemical Drugs, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences in Brno, Palackého 1946/1, CZ-612 42 Brno, Czech Republic.
| | - Ivan Solovič
- Clinic for Tuberculosis and Lung Diseases, National Institute for Tuberculosis, Lung Diseases and Thoracic Surgery, Vyšné Hágy, SK-059 84 Vysoké Tatry, Slovakia.
- Department of Public Health, Faculty of Health, Catholic University in Ružomberok, Hrabovská cesta 1A, SK-034 01 Ružomberok, Slovakia.
| | - Šárka Pospíšilová
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, SK-832 32 Bratislava, Slovakia.
| | - Hana Michnová
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, SK-832 32 Bratislava, Slovakia.
| | - Josef Jampílek
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, SK-832 32 Bratislava, Slovakia.
| | - Alois Čížek
- Clinic for Department of Infectious Diseases and Microbiology, Faculty of Veterinary Medicine, University of Veterinary and Pharmaceutical Sciences, Palackého 1946/1, CZ-612 42 Brno, Czech Republic.
| | - Iva Kapustíková
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, SK-832 32 Bratislava, Slovakia.
| | - Jana Čurillová
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, SK-832 32 Bratislava, Slovakia.
| | - Mária Pecháčová
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, SK-832 32 Bratislava, Slovakia.
| | - Jiřina Stolaříková
- Laboratory for Mycobacterial Diagnostics and Tuberculosis, Regional Institute of Public Health, Partyzánské náměstí 7, CZ-702 00 Ostrava, Czech Republic.
| | - Daniel Pecher
- Department of Pharmaceutical Analysis and Nuclear Pharmacy, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, SK-832 32 Bratislava, Slovakia.
- Toxicological and Antidoping Center, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, SK-832 32 Bratislava, Slovakia.
| | - Michal Oravec
- Global Change Research Institute CAS, Belidla 986/4a, CZ-603 00 Brno, Czech Republic.
| |
Collapse
|
8
|
Dai H, Xu S, Chen J, Miao X, Zhu J. Oxalate enhanced degradation of Orange II in heterogeneous UV-Fenton system catalyzed by Fe 3O 4@γ-Fe 2O 3 composite. Chemosphere 2018; 199:147-153. [PMID: 29433028 DOI: 10.1016/j.chemosphere.2018.02.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [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: 10/10/2017] [Revised: 01/31/2018] [Accepted: 02/04/2018] [Indexed: 06/08/2023]
Abstract
Oxalate enhanced mechanism of Fe3O4@γ-Fe2O3 was developed to provide novel insight into catalytic process regulation of iron oxide catalysts in heterogeneous UV-Fenton system. And the iron oxide composite of Fe3O4@γ-Fe2O3 was characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), fourier transform infrared (FTIR) spectroscopy and nitrogen adsorption-desorption isotherms. The results showed that large amount of iron could be leached from catalyst in the presence of oxalate, which promoted the homogeneous UV-Fenton reactions in solution. Orange II degradation could be significantly enhanced with the increase of the ratio of homogeneous UV-Fenton process to heterogeneous UV-Fenton process. The optimum concentration of oxalate determined by experiment was 0.5 mM in oxalate enhanced heterogeneous UV-Fenton system. On this condition, the pseudo-first-order rate constant value of Orange II degradation was 0.314 min-1, which was 2.3 times as high as that in heterogeneous UV-Fenton system. The removal rates of color and TOC were 100% and 86.6% after 20 min and 120 min treatment, respectively. In addition, the iron ions in solution could be almost completely adsorbed back to the catalyst surface in later degradation stages of Orange II. During the recycle experiments, the results showed that the increase of pH in solution and the sorption of intermediates on the catalyst surface would hinder oxalate enhanced process and lead to a decrease of degradation rate of Orange II in oxalate enhanced heterogeneous UV-Fenton system.
Collapse
Affiliation(s)
- Huiwang Dai
- School of Resources, Environmental and Chemical Engineering, Nanchang University, Nanchang 330031, Jiangxi, China; The Key Laboratory of Poyang Lake Environment and Resource Utilization, Ministry of Education, Nanchang 330031, Jiangxi, China.
| | - Shuying Xu
- School of Resources, Environmental and Chemical Engineering, Nanchang University, Nanchang 330031, Jiangxi, China; The Key Laboratory of Poyang Lake Environment and Resource Utilization, Ministry of Education, Nanchang 330031, Jiangxi, China.
| | - Jianxin Chen
- School of Resources, Environmental and Chemical Engineering, Nanchang University, Nanchang 330031, Jiangxi, China; The Key Laboratory of Poyang Lake Environment and Resource Utilization, Ministry of Education, Nanchang 330031, Jiangxi, China.
| | - Xiaozeng Miao
- School of Resources, Environmental and Chemical Engineering, Nanchang University, Nanchang 330031, Jiangxi, China; The Key Laboratory of Poyang Lake Environment and Resource Utilization, Ministry of Education, Nanchang 330031, Jiangxi, China.
| | - Jianxi Zhu
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences (CAS) Guangzhou, 510640, China; Guangdong Provincial Key Laboratory of Mineral Physics and Materials, 510460, China.
| |
Collapse
|
9
|
Patel M, Yarlagadda V, Adedoyin O, Saini V, Assimos DG, Holmes RP, Mitchell T. Oxalate induces mitochondrial dysfunction and disrupts redox homeostasis in a human monocyte derived cell line. Redox Biol 2017; 15:207-215. [PMID: 29272854 PMCID: PMC5975227 DOI: 10.1016/j.redox.2017.12.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [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: 10/06/2017] [Revised: 12/06/2017] [Accepted: 12/06/2017] [Indexed: 02/06/2023] Open
Abstract
Monocytes/macrophages are thought to be recruited to the renal interstitium during calcium oxalate (CaOx) kidney stone disease for crystal clearance. Mitochondria play an important role in monocyte function during the immune response. We recently determined that monocytes in patients with CaOx kidney stones have decreased mitochondrial function compared to healthy subjects. The objective of this study was to determine whether oxalate, a major constituent found in CaOx kidney stones, alters cell viability, mitochondrial function, and redox homeostasis in THP-1 cells, a human derived monocyte cell line. THP-1 cells were treated with varying concentrations of CaOx crystals (insoluble form) or sodium oxalate (NaOx; soluble form) for 24 h. In addition, the effect of calcium phosphate (CaP) and cystine crystals was tested. CaOx crystals decreased cell viability and induced mitochondrial dysfunction and redox imbalance in THP-1 cells compared to control cells. However, NaOx only caused mitochondrial damage and redox imbalance in THP-1 cells. In contrast, both CaP and cystine crystals did not affect THP-1 cells. Separate experiments showed that elevated oxalate also induced mitochondrial dysfunction in primary monocytes from healthy subjects. These findings suggest that oxalate may play an important role in monocyte mitochondrial dysfunction in CaOx kidney stone disease. Oxalate is a major constituent of calcium oxalate (CaOx) kidney stones and can be found in either soluble or insoluble forms. CaOx crystals are required for CaOx kidney stone formation. Monocytes/macrophages play an important role in crystal clearance. Oxalate causes mitochondrial dysfunction and disrupts redox homeostasis in monocytes.
Collapse
Affiliation(s)
- Mikita Patel
- Department of Urology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Vidhush Yarlagadda
- Department of Urology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Oreoluwa Adedoyin
- Division of Nephrology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Vikram Saini
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Dean G Assimos
- Department of Urology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Ross P Holmes
- Department of Urology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Tanecia Mitchell
- Department of Urology, University of Alabama at Birmingham, Birmingham, AL, United States.
| |
Collapse
|
10
|
Yiu CKY, King NM, Suh BI, Sharp LJ, Carvalho RM, Pashley DH, Tay FR. Incompatibility of Oxalate Desensitizers with Acidic, Fluoride-containing Total-etch Adhesives. J Dent Res 2016; 84:730-5. [PMID: 16040731 DOI: 10.1177/154405910508400809] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [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: 11/17/2022] Open
Abstract
The use of oxalate desensitizers on acid-etched dentin prior to adhesive application can result in subsurface tubular occlusion by calcium oxalate crystals. However, the solubility of calcium oxalate increases in acidic solution. We hypothesized that total-etch adhesives can, depending upon their pH, interact with oxalate-desensitizer-treated dentin in an adverse manner. Acid-etched human dentin treated with 2 oxalate desensitizers (BisBlock and Super Seal) was bonded with 4 simplified total-etch adhesives: One-Step (OS), Single Bond (SB), OptiBond Solo Plus (OB), and Prime&Bond NT (PB). Composite-dentin beams were examined by SEM and TEM, both of which revealed numerous spherical globules on OB- and PB-bonded, desensitizer-treated dentin, but not in OS or SB samples. Bond strengths produced by OB and PB were significantly lower in oxalate-treated specimens than those produced by OS or SB. These surface globules may have interfered with hybridization of demineralized dentin with OB and PB resins and caused compromised bond strengths.
Collapse
Affiliation(s)
- C K Y Yiu
- Paediatric Dentistry and Orthodontics, Faculty of Dentistry, The University of Hong Kong, 34 Hospital Road, Hong Kong SAR, China
| | | | | | | | | | | | | |
Collapse
|
11
|
|
12
|
Langman CB, Grujic D, Pease RM, Easter L, Nezzer J, Margolin A, Brettman L. A Double-Blind, Placebo Controlled, Randomized Phase 1 Cross-Over Study with ALLN-177, an Orally Administered Oxalate Degrading Enzyme. Am J Nephrol 2016; 44:150-8. [PMID: 27529510 DOI: 10.1159/000448766] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [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: 02/20/2016] [Accepted: 07/28/2016] [Indexed: 12/18/2022]
Abstract
BACKGROUND Hyperoxaluria may result from increased endogenous production or overabsorption of dietary oxalate in the gastrointestinal tract leading to nephrolithiasis and, in some, to oxalate nephropathy and chronic kidney disease. ALLN-177 is an oral formulation of a recombinant, oxalate specific, microbial enzyme oxalate decarboxylase intended to treat secondary hyperoxaluria by degrading dietary oxalate in the gastrointestinal tract, thereby reducing its absorption and subsequent excretion in the urine. METHODS This double-blind, placebo controlled, randomized, cross-over, phase 1 study of ALLN-177 evaluated the tolerability of ALLN-177 and its effect on urinary oxalate excretion in 30 healthy volunteers with hyperoxaluria induced by ingestion of a high oxalate, low calcium (HOLC) diet. The primary end point was the difference in the mean 24-hour urinary oxalate excretion during the ALLN-177 treatment period compared with the placebo treatment period. RESULTS The daily urinary oxalate excretion increased in the study population from 27.2 ± 9.5 mg/day during screening to 80.8 ± 24.1 mg/day (mean ± SD) on the HOLC diet before introducing ALLN-177 or placebo therapy for 7 days. Compared to placebo, ALLN-177 treatment reduced urinary oxalate by 11.6 ± 2.7 mg/day, p = 0.0002 (least squares mean ± SD). CONCLUSIONS In healthy volunteers, with diet-induced hyperoxaluria treatment with ALLN-177, when compared to placebo, significantly reduced urinary oxalate excretion by degrading dietary oxalate in the gastrointestinal tract and thereby reducing its absorption. ALLN-177 may represent a new approach for managing secondary hyperoxaluria and its complications.
Collapse
Affiliation(s)
- Craig B Langman
- Division of Kidney Diseases, Department of Pediatrics, Feinberg School of Medicine, Northwestern University, and Lurie Children's Hospital of Chicago, Chicago, Ill., USA
| | | | | | | | | | | | | |
Collapse
|
13
|
Hong MN, Nam KY, Kim KK, Kim SY, Kim I. The small molecule '1-(4-biphenylylcarbonyl)-4-(5-bromo-2-methoxybenzyl) piperazine oxalate' and its derivatives regulate global protein synthesis by inactivating eukaryotic translation initiation factor 2-alpha. Cell Stress Chaperones 2016; 21:485-97. [PMID: 26873011 PMCID: PMC4837177 DOI: 10.1007/s12192-016-0677-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [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] [Received: 09/22/2015] [Revised: 01/29/2016] [Accepted: 01/30/2016] [Indexed: 10/22/2022] Open
Abstract
By environmental stresses, cells can initiate a signaling pathway in which eukaryotic translation initiation factor 2-alpha (eIF2-α) is involved to regulate the response. Phosphorylation of eIF2-α results in the reduction of overall protein neogenesis, which allows cells to conserve resources and to reprogram energy usage for effective stress control. To investigate the role of eIF2-α in cell stress responses, we conducted a viability-based compound screen under endoplasmic reticulum (ER) stress condition, and identified 1-(4-biphenylylcarbonyl)-4-(5-bromo-2-methoxybenzyl) piperazine oxalate (AMC-01) and its derivatives as eIF2-α-inactivating chemical. Molecular characterization of this signaling pathway revealed that AMC-01 induced inactivation of eIF2-α by phosphorylating serine residue 51 in a dose- and time-dependent manner, while the negative control compounds did not affect eIF2-α phosphorylation. In contrast with ER stress induction by thapsigargin, phosphorylation of eIF2-α persisted for the duration of incubation with AMC-01. By pathway analysis, AMC-01 clearly induced the activation of protein kinase RNA-activated (PKR) kinase and nuclear factor-κB (NF-κB), whereas it did not modulate the activity of PERK or heme-regulated inhibitor (HRI). Finally, we could detect a lower protein translation rate in cells incubated with AMC-01, establishing AMC-01 as a potent chemical probe that can regulate eIF2-α activity. We suggest from these data that AMC-01 and its derivative compounds can be used as chemical probes in future studies of the role of eIF2-α in protein synthesis-related cell physiology.
Collapse
Affiliation(s)
- Mi-Na Hong
- Department of Convergence Medicine, Asan Institute for Life Sciences, Asan Medical Center, Convergence Medicine Research Building, 43 gil Olympicro, Pungnapdong, Songpagu, Seoul, 138-736, Republic of Korea
| | - Ky-Youb Nam
- Department of Convergence Medicine, Asan Institute for Life Sciences, Asan Medical Center, Convergence Medicine Research Building, 43 gil Olympicro, Pungnapdong, Songpagu, Seoul, 138-736, Republic of Korea
| | - Kyung Kon Kim
- Department of Convergence Medicine, Asan Institute for Life Sciences, Asan Medical Center, Convergence Medicine Research Building, 43 gil Olympicro, Pungnapdong, Songpagu, Seoul, 138-736, Republic of Korea
- Department of Convergence Medicine, College of Medicine, University of Ulsan, Seoul, Republic of Korea
| | - So-Young Kim
- Department of Convergence Medicine, Asan Institute for Life Sciences, Asan Medical Center, Convergence Medicine Research Building, 43 gil Olympicro, Pungnapdong, Songpagu, Seoul, 138-736, Republic of Korea
| | - InKi Kim
- Department of Convergence Medicine, Asan Institute for Life Sciences, Asan Medical Center, Convergence Medicine Research Building, 43 gil Olympicro, Pungnapdong, Songpagu, Seoul, 138-736, Republic of Korea.
- Department of Convergence Medicine, College of Medicine, University of Ulsan, Seoul, Republic of Korea.
| |
Collapse
|
14
|
Soliman AA, Alajrawy OI, Attabi FA, Shaaban MR, Linert W. New formamidine ligands and their mixed ligand palladium(II) oxalate complexes: Synthesis, characterization, DFT calculations and in vitro cytotoxicity. Spectrochim Acta A Mol Biomol Spectrosc 2016; 152:358-369. [PMID: 26232580 DOI: 10.1016/j.saa.2015.07.076] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [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: 04/17/2015] [Revised: 06/19/2015] [Accepted: 07/16/2015] [Indexed: 06/04/2023]
Abstract
A series of new ternary palladium(II) complexes of the type [Pd(L1-4)ox]·xH2O where L=formamidine ligands and ox=oxalate, were synthesized and characterized by elemental analyses, magnetic susceptibility, UV-Vis, infrared (IR) and mass spectroscopy and thermal analysis. The spectroscopic data indicated that the formamidine ligands act as bidentate N2 donors and the oxalate as O2 ligand. The complexes (1-4) are diamagnetic and the optimization of their structures indicated that the geometry is distorted square planer with O-Pd-O and N-Pd-N bond angles ranged 82.70-83.87° and 88.21-95.02°; respectively which is acceptable for the heteroleptic complexes. The dipole moment of the complexes (13.97-18.77Debye) indicating that the complexes are more polarized than the ligands (1.93-4.96Debye). The complexes are thermally stable as shown from their relatively higher overall activation energies (441-688kJmol(-1)). The ligands and the complexes are proved to have good cytotoxicity with IC50 (μM) in the range of (0.011-0.168) against MCF-7, (0.012-0.150) against HCT-116, (0.042-0.094) against PC-3 and (0.006-0.222) against HepG-2 cell lines, which open the field for further application as antitumor compounds.
Collapse
Affiliation(s)
- Ahmed A Soliman
- Department of Chemistry, Faculty of Science, Cairo University, 12613 Giza, Egypt.
| | - Othman I Alajrawy
- Department of Chemistry, Faculty of Science, Cairo University, 12613 Giza, Egypt; College of Veterinary Medicine, Al-Anbar University, Fallujah, Iraq
| | - Fawzy A Attabi
- Department of Chemistry, Faculty of Science, Cairo University, 12613 Giza, Egypt
| | - Mohamed R Shaaban
- Department of Chemistry, Faculty of Science, Cairo University, 12613 Giza, Egypt; Department of Chemistry, Faculty of Applied Science, Umm Al-Qura University, Makkah, Saudi Arabia
| | - W Linert
- Institute of Applied Synthetic Chemistry, Vienna University of Technology, Getreidemarkt 9/163-AC, A-1060 Vienna, Austria
| |
Collapse
|
15
|
Curreli F, Kwon YD, Zhang H, Scacalossi D, Belov DS, Tikhonov AA, Andreev IA, Altieri A, Kurkin AV, Kwong PD, Debnath AK. Structure-Based Design of a Small Molecule CD4-Antagonist with Broad Spectrum Anti-HIV-1 Activity. J Med Chem 2015; 58:6909-6927. [PMID: 26301736 PMCID: PMC4676410 DOI: 10.1021/acs.jmedchem.5b00709] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [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: 11/28/2022]
Abstract
Earlier we reported the discovery and design of NBD-556 and their analogs which demonstrated their potential as HIV-1 entry inhibitors. However, progress in developing these inhibitors has been stymied by their CD4-agonist properties, an unfavorable trait for use as drug. Here, we demonstrate the successful conversion of a full CD4-agonist (NBD-556) through a partial CD4-agonist (NBD-09027), to a full CD4-antagonist (NBD-11021) by structure-based modification of the critical oxalamide midregion, previously thought to be intolerant of modification. NBD-11021 showed unprecedented neutralization breath for this class of inhibitors, with pan-neutralization against a panel of 56 Env-pseudotyped HIV-1 representing diverse subtypes of clinical isolates (IC50 as low as 270 nM). The cocrystal structure of NBD-11021 complexed to a monomeric HIV-1 gp120 core revealed its detail binding characteristics. The study is expected to provide a framework for further development of NBD series as HIV-1 entry inhibitors for clinical application against AIDS.
Collapse
Affiliation(s)
- Francesca Curreli
- Laboratory of Molecular Modeling and Drug Design, Lindsey F. Kimball Research Institute, New York Blood Center, New York, New York 10065, United States
| | - Young Do Kwon
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Hongtao Zhang
- Laboratory of Molecular Modeling and Drug Design, Lindsey F. Kimball Research Institute, New York Blood Center, New York, New York 10065, United States
| | - Daniel Scacalossi
- Laboratory of Molecular Modeling and Drug Design, Lindsey F. Kimball Research Institute, New York Blood Center, New York, New York 10065, United States
| | - Dmitry S. Belov
- EDASA Scientific, Scientific Park, Moscow State University, Leninskie Gory, Bld.75, 77–101b, 119992 Moscow, Russia
| | - Artur A. Tikhonov
- EDASA Scientific, Scientific Park, Moscow State University, Leninskie Gory, Bld.75, 77–101b, 119992 Moscow, Russia
| | - Ivan A. Andreev
- EDASA Scientific, Scientific Park, Moscow State University, Leninskie Gory, Bld.75, 77–101b, 119992 Moscow, Russia
| | - Andrea Altieri
- EDASA Scientific, Scientific Park, Moscow State University, Leninskie Gory, Bld.75, 77–101b, 119992 Moscow, Russia
| | - Alexander V. Kurkin
- EDASA Scientific, Scientific Park, Moscow State University, Leninskie Gory, Bld.75, 77–101b, 119992 Moscow, Russia
| | - Peter D. Kwong
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Asim K. Debnath
- Laboratory of Molecular Modeling and Drug Design, Lindsey F. Kimball Research Institute, New York Blood Center, New York, New York 10065, United States
| |
Collapse
|
16
|
Han L, Okiji T. Dentin tubule occluding ability of dentin desensitizers. Am J Dent 2015; 28:90-94. [PMID: 26087574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
PURPOSE To compare the dentin tubule-occluding ability of fluoroaluminocalciumsilicate-based (Nanoseal), calcium phosphate-based (Teethmate Desensitizer), resin-containing oxalate (MS Coat ONE) and diamine silver fluoride (Saforide) dentin desensitizers using artificially demineralized bovine dentin. METHODS Simulated hypersensitive dentin was created using cervical dentin sections derived from bovine incisors using phosphoric acid etching followed by polishing with a paste containing hydroxyapatite. The test desensitizers were applied in one, two, or three cycles, where each cycle involved desensitizer application, brushing, and immersion in artificial saliva (n= 5 each). The dentin surfaces were examined with scanning electron microscopy, and the dentin tubule occlusion rate was calculated. The elemental composition of the deposits was analyzed with electron probe microanalysis. Data were analyzed by one-way ANOVA and the Tukey honestly significant different test. RESULTS Marked deposit formation was observed on the specimens treated with Nanoseal or Teethmate Desensitizer, and tags were detected in the specimens' dentin tubules. These findings became more prominent as the number of application cycles increased. The major elemental components of the tags were Ca, F, and Al (Nanoseal) and Ca and P (Teethmate Desensitizer). The tubule occlusion rates of MS Coat ONE and Saforide were significantly lower than those of Nanoseal and Teethmate Desensitizer (P< 0.05).
Collapse
|
17
|
de Oliveira TF, da Silva ALM, de Moura RA, Bagattini R, de Oliveira AAF, de Medeiros MHG, Di Mascio P, de Arruda Campos IP, Barretto FP, Bechara EJH, de Melo Loureiro AP. Luminescent threat: toxicity of light stick attractors used in pelagic fishery. Sci Rep 2014; 4:5359. [PMID: 24942522 PMCID: PMC5381548 DOI: 10.1038/srep05359] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [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: 05/09/2014] [Accepted: 05/30/2014] [Indexed: 11/13/2022] Open
Abstract
Light sticks (LS) are sources of chemiluminescence commonly used in pelagic fishery, where hundreds are discarded and reach the shores. Residents from fishing villages report an improper use of LS contents on the skin. Given the scarce information regarding LS toxicity, the effects of LS solutions in cell cultures were evaluated herein. Loss of viability, cell cycle changes and DNA fragmentation were observed in HepG2 cell line and skin fibroblasts. A non-cytotoxic LS concentration increased the occurrence of the mutagenic lesion 1,N(6)-εdAdo in HepG2 DNA by three-fold. Additionally, in vitro incubations of spent LS contents with DNA generated dGuo-LS adducts, whose structure elucidation revealed the presence of a reactive chlorinated product. In conclusion, the LS contents were found to be highly cyto- and genotoxic. Our data indicate an urgent need for LS waste management guidelines and for adequate information regarding toxic outcomes that may arise from human exposure.
Collapse
Affiliation(s)
- Tiago Franco de Oliveira
- Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, SP, Brazil
- These authors contributed equally to this work
| | - Amanda Lucila Medeiros da Silva
- Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, SP, Brazil
- These authors contributed equally to this work
| | - Rafaela Alves de Moura
- Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Raquel Bagattini
- Instituto de Ciências e Saúde, Universidade Paulista, São Paulo, SP, Brazil
| | - Antonio Anax Falcão de Oliveira
- Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, SP, Brazil
| | | | - Paolo Di Mascio
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil
| | | | | | - Etelvino José Henriques Bechara
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil
- Departamento de Ciências Exatas e da Terra, Universidade Federal de São Paulo, Diadema, SP, Brazil
| | - Ana Paula de Melo Loureiro
- Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, SP, Brazil
| |
Collapse
|
18
|
Guttman M, Garcia NK, Cupo A, Matsui T, Julien JP, Sanders RW, Wilson IA, Moore JP, Lee KK. CD4-induced activation in a soluble HIV-1 Env trimer. Structure 2014; 22:974-84. [PMID: 24931470 DOI: 10.1016/j.str.2014.05.001] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [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: 03/11/2014] [Revised: 04/28/2014] [Accepted: 05/01/2014] [Indexed: 01/05/2023]
Abstract
The HIV envelope glycoprotein (Env) trimer undergoes receptor-induced conformational changes that drive fusion of the viral and cellular membranes. Env conformational changes have been observed using low-resolution electron microscopy, but only large-scale rearrangements have been visible. Here, we use hydrogen-deuterium exchange and oxidative labeling to gain a more precise understanding of the unliganded and CD4-bound forms of soluble Env trimers (SOSIP.664), including their glycan composition. CD4 activation induces the reorganization of bridging sheet elements, V1/V2 and V3, much of the gp120 inner domain, and the gp41 fusion subunit. Two CD4 binding site-targeted inhibitors have substantially different effects: NBD-556 partially mimics CD4-induced destabilization of the V1/V2 and V3 crown, whereas BMS-806 only affects regions around the gp120/gp41 interface. The structural information presented here increases our knowledge of CD4- and small molecule-induced conformational changes in Env and the allosteric pathways that lead to membrane fusion.
Collapse
Affiliation(s)
- Miklos Guttman
- Department of Medicinal Chemistry, University of Washington, Seattle, WA 98195, USA
| | - Natalie K Garcia
- Department of Medicinal Chemistry, University of Washington, Seattle, WA 98195, USA
| | - Albert Cupo
- Weill Medical College of Cornell University, New York, NY 10021, USA
| | - Tsutomu Matsui
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Jean-Philippe Julien
- Department of Integrative Structural and Computational Biology, International AIDS Vaccine Initiative Neutralizing Antibody Center, Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, and Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Rogier W Sanders
- Weill Medical College of Cornell University, New York, NY 10021, USA; Department of Medical Microbiology, Academic Medical Center, 1105 AZ Amsterdam, the Netherlands
| | - Ian A Wilson
- Department of Integrative Structural and Computational Biology, International AIDS Vaccine Initiative Neutralizing Antibody Center, Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, and Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - John P Moore
- Weill Medical College of Cornell University, New York, NY 10021, USA
| | - Kelly K Lee
- Department of Medicinal Chemistry, University of Washington, Seattle, WA 98195, USA.
| |
Collapse
|
19
|
Khan A, Wang W, Khan SR. Calcium oxalate nephrolithiasis and expression of matrix GLA protein in the kidneys. World J Urol 2014; 32:123-30. [PMID: 23475213 PMCID: PMC3731399 DOI: 10.1007/s00345-013-1050-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Accepted: 02/25/2013] [Indexed: 01/17/2023] Open
Abstract
OBJECTIVES Polymorphism of the gene for matrix GLA protein (MGP), a calcification inhibitor, is associated with nephrolithiasis. However, experimental investigations of MGP role in stone pathogenesis are limited. We determined the effect of renal epithelial exposure to oxalate (Ox), calcium oxalate (CaOx) monohydrate (COM) or hydroxyapatite (HA) crystal on the expression of MGP. METHODS MDCK cells in culture were exposed to 0.3, 0.5 or 1 mM Ox and 33, 66 or 133-150 μg/cm(2) of COM/HA for 3-72 h. MGP expression and production were determined by Western blotting and densitometric analysis. Enzyme-linked immunosorbent assay was performed to determine MGP release into the medium. Hyperoxaluria was induced in male Sprague-Dawley rats by feeding hydroxyl-L-proline. Immunohistochemistry was performed to detect renal MGP expression. RESULTS Exposure to Ox and crystals led to time- and concentration-dependent increase in expression of MGP in MDCK cells. Cellular response was quicker to crystal exposure than to the Ox, expression being significantly higher after 3-h exposure to COM or HA crystals and more than 6 h of exposure to Ox. MGP expression was increased in kidneys of hyperoxaluric rats particularly in renal peritubular vessels. CONCLUSION We demonstrate increased expression of MGP in renal tubular epithelial cells exposed to Ox or CaOx crystals as well as the HA crystals. The most significant finding of this study is the increased staining seen in renal peritubular vessels of the hyperoxaluric rats, indicating involvement of renal endothelial cells in the synthesis of MGP.
Collapse
Affiliation(s)
- Aslam Khan
- Department of Pathology, Immunology & Laboratory Medicine, University of Florida College of Medicine, Gainesville, FL, 32610, USA
| | | | | |
Collapse
|
20
|
Khandrika L, Koul S, Meacham RB, Koul HK. Kidney injury molecule-1 is up-regulated in renal epithelial cells in response to oxalate in vitro and in renal tissues in response to hyperoxaluria in vivo. PLoS One 2012; 7:e44174. [PMID: 22984472 PMCID: PMC3440413 DOI: 10.1371/journal.pone.0044174] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [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] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Accepted: 07/30/2012] [Indexed: 01/28/2023] Open
Abstract
Oxalate is a metabolic end product excreted by the kidney. Mild increases in urinary oxalate are most commonly associated with Nephrolithiasis. Chronically high levels of urinary oxalate, as seen in patients with primary hyperoxaluria, are driving factor for recurrent renal stones, and ultimately lead to renal failure, calcification of soft tissue and premature death. In previous studies others and we have demonstrated that high levels of oxalate promote injury of renal epithelial cells. However, methods to monitor oxalate induced renal injury are limited. In the present study we evaluated changes in expression of Kidney Injury Molecule-1 (KIM-1) in response to oxalate in human renal cells (HK2 cells) in culture and in renal tissue and urine samples in hyperoxaluric animals which mimic in vitro and in vivo models of hyper-oxaluria. Results presented, herein demonstrate that oxalate exposure resulted in increased expression of KIM-1 m RNA as well as protein in HK2 cells. These effects were rapid and concentration dependent. Using in vivo models of hyperoxaluria we observed elevated expression of KIM-1 in renal tissues of hyperoxaluric rats as compared to normal controls. The increase in KIM-1 was both at protein and mRNA level, suggesting transcriptional activation of KIM-1 in response to oxalate exposure. Interestingly, in addition to increased KIM-1 expression, we observed increased levels of the ectodomain of KIM-1 in urine collected from hyperoxaluric rats. To the best of our knowledge our studies are the first direct demonstration of regulation of KIM-1 in response to oxalate exposure in renal epithelial cells in vitro and in vivo. Our results suggest that detection of KIM-1 over-expression and measurement of the ectodomain of KIM-1 in urine may hold promise as a marker to monitor oxalate nephrotoxicity in hyperoxaluria.
Collapse
Affiliation(s)
- Lakshmipathi Khandrika
- Signal Transduction and Molecular Urology Laboratory-Program in Urosciences, Division of Urology- Department of Surgery, School of Medicine, University of Colorado at Denver, Aurora, Colorado, United States of America
| | - Sweaty Koul
- Signal Transduction and Molecular Urology Laboratory-Program in Urosciences, Division of Urology- Department of Surgery, School of Medicine, University of Colorado at Denver, Aurora, Colorado, United States of America
| | - Randall B. Meacham
- Signal Transduction and Molecular Urology Laboratory-Program in Urosciences, Division of Urology- Department of Surgery, School of Medicine, University of Colorado at Denver, Aurora, Colorado, United States of America
| | - Hari K. Koul
- Signal Transduction and Molecular Urology Laboratory-Program in Urosciences, Division of Urology- Department of Surgery, School of Medicine, University of Colorado at Denver, Aurora, Colorado, United States of America
- University of Colorado Comprehensive Cancer Center, University of Colorado at Denver, Anschutz Medical Campus, Aurora, Colorado, United States of America
- Denver Veterans Administration Medical Center, Denver, Colorado, United States of America
- * E-mail:
| |
Collapse
|
21
|
Zargoosh K, Shamsipur M, Qandalee M, Piltan M, Moradi L. Sensitive and selective determination of glucose in human serum and urine based on the peroxyoxalate chemiluminescence reaction of a new fluorophore. Spectrochim Acta A Mol Biomol Spectrosc 2011; 81:679-683. [PMID: 21795102 DOI: 10.1016/j.saa.2011.07.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Revised: 06/29/2011] [Accepted: 07/01/2011] [Indexed: 05/31/2023]
Abstract
A novel method for simple and sensitive determination of glucose based on the peroxyoxalate chemiluminescence (PO-CL) detection of enzymatically generated H(2)O(2) was investigated. Influence of various experimental parameters on glucose sensing, including the action time of the enzyme, solution pH, interferents and the concentration of CL reagents was investigated. Under the optimum condition, the linear response range of glucose was found to be 2.50×10(-6) to 1.75×10(-4) mol/L, and the detection limit (defined as the concentration that could be detected at the signal-to-noise ratio of 3) was 1.10×10(-6) mol/L. The present method has been used to determine the glucose concentrations in real serum and urine samples with satisfactory results.
Collapse
Affiliation(s)
- Kiomars Zargoosh
- Department of Chemistry, Isfahan University of Technology, Isfahan, Iran.
| | | | | | | | | |
Collapse
|
22
|
Degu A, Hatew B, Nunes-Nesi A, Shlizerman L, Zur N, Katz E, Fernie AR, Blumwald E, Sadka A. Inhibition of aconitase in citrus fruit callus results in a metabolic shift towards amino acid biosynthesis. Planta 2011; 234:501-13. [PMID: 21528417 DOI: 10.1007/s00425-011-1411-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2011] [Accepted: 03/28/2011] [Indexed: 05/08/2023]
Abstract
Citrate, a major determinant of citrus fruit quality, accumulates early in fruit development and declines towards maturation. The isomerization of citrate to isocitrate, catalyzed by aconitase is a key step in acid metabolism. Inhibition of mitochondrial aconitase activity early in fruit development contributes to acid accumulation, whereas increased cytosolic activity of aconitase causes citrate decline. It was previously hypothesized that the block in mitochondrial aconitase activity, inducing acid accumulation, is caused by citramalate. Here, we investigated the effect of citramalate and of another aconitase inhibitor, oxalomalate, on aconitase activity and regulation in callus originated from juice sacs. These compounds significantly increased citrate content and reduced the enzyme's activity, while slightly inducing its protein level. Citramalate inhibited the mitochondrial, but not cytosolic form of the enzyme. Its external application to mandarin fruits resulted in inhibition of aconitase activity, with a transient increase in fruit acidity detected a few weeks later. The endogenous level of citramalate was analyzed in five citrus varieties: its pattern of accumulation challenged the notion of its action as an endogenous inhibitor of mitochondrial aconitase. Metabolite profiling of oxalomalate-treated cells showed significant increases in a few amino acids and organic acids. The activities of alanine transaminase, aspartate transaminase and aspartate kinase, as well as these of two γ-aminobutyrate (GABA)-shunt enzymes, succinic semialdehyde reductase (SSAR) and succinic semialdehyde dehydrogenase (SSAD) were significantly induced in oxalomalate-treated cells. It is suggested that the increase in citrate, caused by aconitase inhibition, induces amino acid synthesis and the GABA shunt, in accordance with the suggested fate of citrate during the acid decline stage in citrus fruit.
Collapse
Affiliation(s)
- Asfaw Degu
- Department of Fruit Tree Sciences, ARO, The Volcani Center, P.O. Box 6, Bet Dagan 50250, Israel
| | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Williams B, Kabbage M, Kim HJ, Britt R, Dickman MB. Tipping the balance: Sclerotinia sclerotiorum secreted oxalic acid suppresses host defenses by manipulating the host redox environment. PLoS Pathog 2011; 7:e1002107. [PMID: 21738471 PMCID: PMC3128121 DOI: 10.1371/journal.ppat.1002107] [Citation(s) in RCA: 279] [Impact Index Per Article: 21.5] [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: 01/24/2011] [Accepted: 04/22/2011] [Indexed: 12/21/2022] Open
Abstract
Sclerotinia sclerotiorum is a necrotrophic ascomycete fungus with an extremely broad host range. This pathogen produces the non-specific phytotoxin and key pathogenicity factor, oxalic acid (OA). Our recent work indicated that this fungus and more specifically OA, can induce apoptotic-like programmed cell death (PCD) in plant hosts, this induction of PCD and disease requires generation of reactive oxygen species (ROS) in the host, a process triggered by fungal secreted OA. Conversely, during the initial stages of infection, OA also dampens the plant oxidative burst, an early host response generally associated with plant defense. This scenario presents a challenge regarding the mechanistic details of OA function; as OA both suppresses and induces host ROS during the compatible interaction. In the present study we generated transgenic plants expressing a redox-regulated GFP reporter. Results show that initially, Sclerotinia (via OA) generates a reducing environment in host cells that suppress host defense responses including the oxidative burst and callose deposition, akin to compatible biotrophic pathogens. Once infection is established however, this necrotroph induces the generation of plant ROS leading to PCD of host tissue, the result of which is of direct benefit to the pathogen. In contrast, a non-pathogenic OA-deficient mutant failed to alter host redox status. The mutant produced hypersensitive response-like features following host inoculation, including ROS induction, callose formation, restricted growth and cell death. These results indicate active recognition of the mutant and further point to suppression of defenses by the wild type necrotrophic fungus. Chemical reduction of host cells with dithiothreitol (DTT) or potassium oxalate (KOA) restored the ability of this mutant to cause disease. Thus, Sclerotinia uses a novel strategy involving regulation of host redox status to establish infection. These results address a long-standing issue involving the ability of OA to both inhibit and promote ROS to achieve pathogenic success. Necrotrophic fungal pathogens need to kill plant cells to establish disease and obtain nutrition. While such pathogens are economically important, they are relatively understudied and mechanistic details important for pathogenic success are limited. Sclerotinia sclerotiorum is a necrotrophic ascomycete fungus that infects virtually all dicotyledonous (>400 species) plants. Our data indicate that oxalic acid production and modulation of reactive oxygen species (ROS) are key components for the successful interaction of this fungus with the host plant. Here, we use a GFP regulated reporter system to analyze the host redox status during infections with wild type and a non-pathogenic oxalic acid (OA) deficient Sclerotinia mutant. Additionally, we show that secreted OA enables Sclerotinia to hijack the host cell redox machinery, initially creating reducing conditions followed by an oxidizing environment that is necessary for pathogenesis. We also provide evidence that the OA-deficient mutants are actively recognized by the plant resulting in the elicitation of a hypersensitive-like response and resistance. Our study provides insight into how Sclerotinia, and quite possibly other necrotrophic pathogens, co-opt host redox and cell death pathways for successful colonization of the host.
Collapse
Affiliation(s)
- Brett Williams
- Institute for Plant Genomics and Biotechnology, Department of Plant Pathology and Microbiology, Texas A&M University, College Station, Texas, United States of America
| | - Mehdi Kabbage
- Institute for Plant Genomics and Biotechnology, Department of Plant Pathology and Microbiology, Texas A&M University, College Station, Texas, United States of America
| | - Hyo-Jin Kim
- Institute for Plant Genomics and Biotechnology, Department of Plant Pathology and Microbiology, Texas A&M University, College Station, Texas, United States of America
| | - Robert Britt
- Institute for Plant Genomics and Biotechnology, Department of Plant Pathology and Microbiology, Texas A&M University, College Station, Texas, United States of America
| | - Martin B. Dickman
- Institute for Plant Genomics and Biotechnology, Department of Plant Pathology and Microbiology, Texas A&M University, College Station, Texas, United States of America
- * E-mail:
| |
Collapse
|
24
|
Gu H, Ling J, LeGeros JP, LeGeros RZ. Calcium phosphate-based solutions promote dentin tubule occlusions less susceptible to acid dissolution. Am J Dent 2011; 24:169-175. [PMID: 21874938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
PURPOSE To determine the efficacy supersaturated calcium phosphate (CaP) solutions containing fluoride (F) and zinc (Zn) ions in occluding dentin tubules with precipitates less susceptible to acid dissolution and to compare the performance of these solutions with the oxalate solutions containing calcium (Ca) or phosphate (P) ions. METHODS Dentin sections from human molars divided into groups: Group A - control (treated with double distilled H2O), Groups A1, A2 and A3 were treated with experimental solutions supersaturated with respect to F and Zn-substituted calcium phosphates. Solutions A1 and A2 were similar in composition but differed in pH values (A1, pH 7; A2, pH 5.5). Solutions A2 and A3 were similar in pH (pH 5.5) but the A3 solution had twice the concentrations of F and Zn2+ ions compared to A2. Another group of dentin sections were treated with A3 solution, oxalate solution containing Ca (OX/Ca) and OX solution containing P (OX/P). The control and treated dentin sections were characterized using scanning electron microscopy. RESULTS All treated dentin sections showed occluded dentin tubules; with the group A3 showing the highest percent of occluded dentin tubules. The precipitates in the dentin tubules treated with A3 remained while those treated with OX/Ca or OX/P dissolved after exposure to an acidic buffer.
Collapse
Affiliation(s)
- Haijing Gu
- Department of Pediatric Dentistry, Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, China
| | | | | | | |
Collapse
|
25
|
Xu W, Yang H, Liu Y, Yang Y, Wang P, Kim SH, Ito S, Yang C, Wang P, Xiao MT, Liu LX, Jiang WQ, Liu J, Zhang JY, Wang B, Frye S, Zhang Y, Xu YH, Lei QY, Guan KL, Zhao SM, Xiong Y. Oncometabolite 2-hydroxyglutarate is a competitive inhibitor of α-ketoglutarate-dependent dioxygenases. Cancer Cell 2011; 19:17-30. [PMID: 21251613 PMCID: PMC3229304 DOI: 10.1016/j.ccr.2010.12.014] [Citation(s) in RCA: 2067] [Impact Index Per Article: 159.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Revised: 11/19/2010] [Accepted: 12/16/2010] [Indexed: 12/14/2022]
Abstract
IDH1 and IDH2 mutations occur frequently in gliomas and acute myeloid leukemia, leading to simultaneous loss and gain of activities in the production of α-ketoglutarate (α-KG) and 2-hydroxyglutarate (2-HG), respectively. Here we demonstrate that 2-HG is a competitive inhibitor of multiple α-KG-dependent dioxygenases, including histone demethylases and the TET family of 5-methlycytosine (5mC) hydroxylases. 2-HG occupies the same space as α-KG does in the active site of histone demethylases. Ectopic expression of tumor-derived IDH1 and IDH2 mutants inhibits histone demethylation and 5mC hydroxylation. In glioma, IDH1 mutations are associated with increased histone methylation and decreased 5-hydroxylmethylcytosine (5hmC). Hence, tumor-derived IDH1 and IDH2 mutations reduce α-KG and accumulate an α-KG antagonist, 2-HG, leading to genome-wide histone and DNA methylation alterations.
Collapse
Affiliation(s)
- Wei Xu
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
- Molecular and Cell Biology Lab, Institutes of Biomedical Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
| | - Hui Yang
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
- Molecular and Cell Biology Lab, Institutes of Biomedical Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
| | - Ying Liu
- Department of Pathology, Shanghai Medical School, Fudan University, Shanghai 20032, China
| | - Ying Yang
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
| | - Ping Wang
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
| | - Se-Hee Kim
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, NC 27599, USA
| | - Shinsuke Ito
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, NC 27599, USA
- Howard Hughes Medical Institute, University of North Carolina at Chapel Hill, NC 27599, USA
| | - Chen Yang
- Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Pu Wang
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
- Molecular and Cell Biology Lab, Institutes of Biomedical Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
| | - Meng-Tao Xiao
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
- Molecular and Cell Biology Lab, Institutes of Biomedical Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
| | - Li-xia Liu
- Department of Biochemistry, Shanghai Medical School, Fudan University, Shanghai 20032, China
| | - Wen-qing Jiang
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
- Molecular and Cell Biology Lab, Institutes of Biomedical Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
| | - Jing Liu
- Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Jin-ye Zhang
- Molecular and Cell Biology Lab, Institutes of Biomedical Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
| | - Bin Wang
- Department of Biological Chemistry, Shanghai Medical School, Fudan University, Shanghai 20032, China
| | - Stephen Frye
- Center for Integrative Chemical Biology and Drug Discovery, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC 27599, USA
| | - Yi Zhang
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, NC 27599, USA
- Howard Hughes Medical Institute, University of North Carolina at Chapel Hill, NC 27599, USA
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, NC 27599, USA
| | - Yan-hui Xu
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
| | - Qun-ying Lei
- Molecular and Cell Biology Lab, Institutes of Biomedical Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
- Department of Biochemistry, Shanghai Medical School, Fudan University, Shanghai 20032, China
| | - Kun-Liang Guan
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
- Molecular and Cell Biology Lab, Institutes of Biomedical Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
- Department of Biochemistry, Shanghai Medical School, Fudan University, Shanghai 20032, China
- Department of Pharmacology and Moores Cancer Center, University of California San Diego, La Jolla, CA 92093, USA
- Correspondence: (K.-L.G.), (S.-m.Z.), (Y.X.)
| | - Shi-min Zhao
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
- Molecular and Cell Biology Lab, Institutes of Biomedical Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
- Correspondence: (K.-L.G.), (S.-m.Z.), (Y.X.)
| | - Yue Xiong
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
- Molecular and Cell Biology Lab, Institutes of Biomedical Sciences, Shanghai Medical School, Fudan University, Shanghai 20032, China
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, NC 27599, USA
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, NC 27599, USA
- Correspondence: (K.-L.G.), (S.-m.Z.), (Y.X.)
| |
Collapse
|
26
|
Kawashiri T, Egashira N, Watanabe H, Ikegami Y, Hirakawa S, Mihara Y, Yano T, Ikesue H, Oishi R. Prevention of oxaliplatin-induced mechanical allodynia and neurodegeneration by neurotropin in the rat model. Eur J Pain 2010; 15:344-50. [PMID: 20829082 DOI: 10.1016/j.ejpain.2010.08.006] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2010] [Revised: 07/13/2010] [Accepted: 08/13/2010] [Indexed: 12/27/2022]
Abstract
Oxaliplatin is a key drug for colorectal cancer, but it causes acute peripheral neuropathy (triggered by cold) and chronic neuropathy (sensory and motor neuropathy) in patients. Neurotropin, a non-protein extract from the inflamed rabbit skin inoculated with vaccinia virus, has been used to treat various chronic pains. In the present study, we investigated the effect of neurotropin on the oxaliplatin-induced neuropathy in rats. Repeated administration of oxaliplatin caused cold hyperalgesia from Day 5 to Day 29 and mechanical allodynia from Day 15 to Day 47. Repeated administration of neurotropin relieved the oxaliplatin-induced mechanical allodynia but not cold hyperalgesia, and inhibited the oxaliplatin-induced axonal degeneration in rat sciatic nerve. Neurotropin also inhibited the oxaliplatin-induced neurite degeneration in cultured pheochromocytoma 12 (PC12) and rat dorsal root ganglion (DRG) cells. On the other hand, neurotropin did not affect the oxaliplatin-induced cell injury in rat DRG cells. These results suggest that repeated administration of neurotropin relieves the oxaliplatin-induced mechanical allodynia by inhibiting the axonal degeneration and it is useful for the treatment of oxaliplatin-induced neuropathy clinically.
Collapse
Affiliation(s)
- Takehiro Kawashiri
- Department of Pharmacy, Kyushu University Hospital, Fukuoka 812-8582, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Nandakumar K, Bansal SK, Singh R, Bodhankar SL, Jindal DP, Coumar MS, Balaraman R, Bhardwaj SH. Selective β1-adrenoreceptor blocking activity of newly synthesized acyl amino-substituted aryloxypropanolamine derivatives, DPJ 955 and DPJ 890, in rats. J Pharm Pharmacol 2010; 57:515-9. [PMID: 15831214 DOI: 10.1211/0022357055768] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [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: 12/26/2022]
Abstract
Abstract
The in-vivo β-adrenoreceptor antagonistic activity of test compounds DPJ 955 and DPJ 890 was assessed against β-adrenoreceptor agonist (isoprenaline) induced tachycardia in anaesthetized rats. The selectivity to block isoprenaline responses on different β-adrenoreceptor subtypes (β1, β2 and β3) of the test compounds was carried out on isolated rat right atria, isolated rat uterus and isolated rat colon preparations, respectively. Intravenous injection of isoprenaline alone in anaesthetized rats caused hypotension and tachycardia. DPJ 955 or DPJ 890 alone produced a fall in mean arterial pressure and bradycardia in a dose-dependent manner. Administration of isoprenaline to anaesthetized rats pre-treated with test compounds significantly blocked both the tachycardial and hypotensive responses induced by isoprenaline. The test compounds shifted the concentration response curves of isoprenaline towards the right for isolated rat right atrial preparations, rat uterus and rat colon, indicating β1, β2 and β3 adrenoreceptor blockade, respectively. The selectivity ratio for β1/β-adrenoreceptors to DPJ 955 and DPJ 890 was 64.6 and 83.2, respectively. DPJ 890 was more potent in blocking β1-adrenoreceptors and was more selective towards β1 receptors than to other β-adrenoreceptor subtypes. In conclusion, DPJ 955 and DPJ890 have β-adrenoreceptor blocking activity with high selectivity for the β1-adrenoreceptor subtype.
Collapse
Affiliation(s)
- K Nandakumar
- Department of Pharmacology, Poona College of Pharmacy, Bharati Vidyapeeth Deemed University, Erandwane, Pune 411 038, India
| | | | | | | | | | | | | | | |
Collapse
|
28
|
Shamsipur M, Zargoosh K, Hosseini SM, Caltagirone C, Lippolis V. Quenching effect of some heavy metal ions on the fast peroxyoxalate-chemiluminescence of 1-(dansylamidopropyl)-1-aza-4,7,10-trithiacyclododecane as a novel fluorophore. Spectrochim Acta A Mol Biomol Spectrosc 2009; 74:205-209. [PMID: 19570707 DOI: 10.1016/j.saa.2009.06.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2008] [Revised: 05/17/2009] [Accepted: 06/07/2009] [Indexed: 05/28/2023]
Abstract
The fast chemiluminescence (CL) arising from the reaction of bis(2,4,6-trichlorophenyl)oxalate (TCPO) with hydrogen peroxide in the presence of 1-(dansylamidopropyl)-1-aza-4,7,10-trithiacyclododecane (L) as a novel fluorophore, and imidazole as catalyst, has been studied in ethyl acetate solution. The relationships between the chemiluminescence intensity and concentrations of TCPO, imidazole, hydrogen peroxide and L are reported. In the presence of imidazole as catalyst, the entire CL signal was completed in less than 3s. The quenching effect of Cu(2+), Pb(2+), Cd(2+), Hg(2+) and Ag(+) ions on the chemiluminescent system was investigated, the resulting Stern-Volmer plots were obtained and the K(Q) values were calculated. It was found that the quenching effect of metal ions on the chemiluminescence of L decreases in the order Cu(2+)>Pb(2+)>Cd(2+)>Hg(2+)>Ag(+).
Collapse
|
29
|
Oberg C, Pochapski MT, Farago PV, Granado CJF, Pilatti GL, Santos FA. Evaluation of desensitizing agents on dentin permeability and dentinal tubule occlusion: an in vitro study. Gen Dent 2009; 57:496-536. [PMID: 19903641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
One hundred twelve specimens from bovine incisors were divided into eight groups: Group 1 (treated with 10% strontium chloride gel), Group 2 (treated with 2% sodium fluoride gel), Group 3 (treated with 2% stannous fluoride gel), Group 4 (treated with 5% potassium nitrate gel), Group 5 (treated with 10% potassium nitrate gel), Group 6 (treated with 3% potassium oxalate gel), Group 7 (treated with hydroxyethylcellulose gel), and Group 8 (which received no treatment). Dentinal tubules were exposed after 0.5 mm of deep abrasion using a carbide bur and EDTA gel application. After each treatment, dentin permeability, tubule occlusion, and chemical elements on dentin were analyzed. There was a significant difference among groups in dentin permeability (p < 0.05 ANOVA). Groups 4, 5, and 6 showed the lowest values, while Groups 1, 7, and 8 exhibited the highest. Groups 1, 2, 3, 7, and 8 showed open dentinal tubules, Groups 4 and 5 had partial tubule occlusion, and most of the tubules in Group 6 were obliterated. Energy-dispersive x-rays revealed similar chemical characteristics among the experimental agents used, with traces of strontium, fluoride, sodium, and potassium. Within the limits of the study, 3% potassium oxalate gel showed the best results in terms of dentin permeability and dentinal tubule occlusion.
Collapse
Affiliation(s)
- Carolina Oberg
- Department of Dentistry, State University of Ponta Grossa, Parana, Brazil
| | | | | | | | | | | |
Collapse
|
30
|
Sauro S, Watson TF, Mannocci F, Tay FR, Pashley DH. Prevention of water contamination of ethanol-saturated dentin and hydrophobic hybrid layers. J Adhes Dent 2009; 11:271-278. [PMID: 19701507 PMCID: PMC3819625] [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] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
PURPOSE This in vitro study evaluated the amount and distribution of outward fluid flow that occurred when an experimental etch-and-rinse hydrophobic adhesive was applied to ethanol-saturated dentin before and after oxalate pretreatment. MATERIALS AND METHODS Measurements of dentin permeability were performed under a constant pulpal pressure of 20 cm H2O in deep and middle dentin. A lucifer yellow solution was placed in the pulp chamber to determine the distribution of the water contamination of the hybrid layers. RESULTS The distribution of fluorescence in dentin specimens that were not pretreated with oxalate revealed that the dye permeated around the resin tags and filled the hybrid layer. Dentin specimens pretreated with oxalate prior to resin bonding, showed 80% to 83% less (p < 0.05) water contamination compared to controls. The dentin permeability results obtained before and after oxalate pretreatment showed that oxalate decreased dentin permeability by 98% (p < 0.05) compared to acid-etched controls. This prevented outward fluid movement during bonding, resulting in better resin sealing of dentin due to the formation of a double seal of resin tags over calcium oxalate crystals in the tubules. CONCLUSION Outward dentinal fluid flow may contaminate hybrid layers during adhesive bonding procedures. Pretreatment of acid-etched dentin with 3% oxalic acid prior to bonding procedures can prevent outward fluid flow during bonding and water contamination of the hydrophobic hybrid layers.
Collapse
Affiliation(s)
- Salvatore Sauro
- Dental Biomaterials Science, Biomimetics & Biophotonics, King’s College London Dental Institute, Guy’s, King’s College and St Thomas’ Hospitals, Floor 17 Guy’s Tower, London, UK
| | - Timothy F Watson
- Biomaterials, Biomimetics & Biophotonics Research Group (B), King’s College London Dental Institute, Guy’s, King’s College and St Thomas’ Hospitals, Floor 17 Guy’s Tower, London, UK
| | - Francesco Mannocci
- Department of Conservative Dentistry King’s College London Dental Institute, Guy’s, King’s College and St Thomas’ Hospitals, Floor 17 Guy’s Tower, London, UK
| | - Franklin R Tay
- Department of Endodontics, Dental Research Center School of Dentistry, Medical College of Georgia, 1120 15th Street, CL2112, Augusta, GA, USA
| | - David H Pashley
- Bioengineering Research, Dental Research Center School of Dentistry, Medical College of Georgia, 1120 15th Street, CL2112, Augusta, GA, USA
| |
Collapse
|
31
|
|
32
|
Ishihata H, Kanehira M, Nagai T, Finger WJ, Shimauchi H, Komatsu M. Effect of desensitizing agents on dentin permeability. Am J Dent 2009; 22:143-146. [PMID: 19650593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
PURPOSE To investigate the in vitro efficacy of two dentin desensitizing products at reducing liquid permeability through human dentin discs. The tested hypothesis was that the products, in spite of different chemical mechanisms were not different at reducing or eliminating flow through dentin discs. METHODS Dentin slices (1 mm thick) were prepared from 16 extracted human third molars and their permeability was indirectly recorded in a split chamber model, using a chemiluminescence technique, after EDTA treatment (control), after soaking with albumin, and after desensitizer application. Two products were studied: MS Coat, a self-curing resin-containing oxalate product, and Gluma Desensitizer, a glutaraldehyde/HEMA-based agent without initiator. The dentin slices were mounted between an upper chamber, filled with an aqueous solution of 1% potassium ferricyanide and 0.3% hydrogen peroxide, and a lower chamber filled with 1% sodium hydroxide solution and 0.02% luminol. The upper solution was pressurized, and upon contact with the luminol solution a photochemical signal was generated and recorded as a measure of permeability throughout two consecutive pressurizing cycles at 2.5 and 13 kPa (26 and 133 cm H2O), respectively. RESULTS The permeability of the control and albumin-soaked samples was similarly high. After application of the desensitizing agents, dentin permeability was reduced to virtually zero at both pressure levels (P < 0.001).
Collapse
Affiliation(s)
- Hiroshi Ishihata
- Department of Restorative Dentistry, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | | | | | | | | | | |
Collapse
|
33
|
|
34
|
|
35
|
EASTHAM RD, DENSON KW, EVANS DA. The Effects of Sodium Citrate and Potassium Ammonium Oxalate on the Erythrocyte Sedimentation Rate. ACTA ACUST UNITED AC 2009; 161:277-88. [PMID: 13544878 DOI: 10.1111/j.0954-6820.1958.tb15545.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
36
|
Norberg B, Söderström N. The effect of demecolcine on the oxalate-induced formation of radial-segmented nuclei (Rieder cells). Scand J Haematol 2009; 4:161-8. [PMID: 6048638 DOI: 10.1111/j.1600-0609.1967.tb01615.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
37
|
|
38
|
Norberg B, Söderström N. "Radial segmentation" of the nuclei in lymphocytes and other blood cells induced by some anticoagulants. Scand J Haematol 2009; 4:68-76. [PMID: 4961990 DOI: 10.1111/j.1600-0609.1967.tb01600.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
|
39
|
Bandmann U, Norberg B, Rydgren L. Polymorphonuclear leucocyte chemotaxis in Boyden chambers. Effect of low concentrations of vinblastine. Scand J Haematol 2009; 13:305-12. [PMID: 4445828 DOI: 10.1111/j.1600-0609.1974.tb00274.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
40
|
Jajoo A, Sahay A, Singh P, Mathur S, Zharmukhamedov SK, Klimov VV, Allakhverdiev SI, Bharti S. Elucidating the site of action of oxalate in photosynthetic electron transport chain in spinach thylakoid membranes. Photosynth Res 2008; 97:177-184. [PMID: 18563623 DOI: 10.1007/s11120-008-9314-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2008] [Accepted: 05/19/2008] [Indexed: 05/26/2023]
Abstract
The effects of oxalate on PS II and PS I photochemistry were studied. The results suggested that in chloride-deficient thylakoid membranes, oxalate inhibited activity of PS II as well as PS I. To our knowledge, this is the only anion so far known which inhibits both the photosystems. Measurements of fluorescence induction kinetics, YZ* decay, and S2 state multiline EPR signal suggested that oxalate inhibited PS II at the donor side most likely on the oxygen evolving complex. Measurements of re-reduction of P700+ signal in isolated PS I particles in oxalate-treated samples suggested a binding site of oxalate on the donor, as well as the acceptor side of PS I.
Collapse
Affiliation(s)
- Anjana Jajoo
- School of Life Sciences, Devi Ahilya University, Vigyan Bhavan, Khandwa Road, Indore 452017, M.P., India.
| | | | | | | | | | | | | | | |
Collapse
|
41
|
de Andrade e Silva SM, Marquezini L, Manso AP, Garcia FP, Carrilho MRDO, Pashley DH, Tay FR, Carvalho RM. Effects of a combined application of potassium oxalate gel/adhesive agent on dentin permeability in vitro. J Adhes Dent 2007; 9:505-512. [PMID: 18265707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
PURPOSE To test the effects of sequential application of potassium oxalate gel/adhesive agent on in vitro dentin permeability. MATERIALS AND METHODS Full crown preparations were made in extracted human molars to expose deep coronal dentin. The roots and pulp were removed and the resulting crown segments were connected to a special device (Flodec) to permit the measurement of the permeability of the specimens before and after treatments. Minimum and maximum permeability were recorded after smear layer and phosphoric acid treatment. A new smear layer was created and the permeability measured after the crowns were bonded with Single Bond (3M ESPE), One-Up Bond F (Tokuyama), and AdheSE (Ivoclar Vivadent), either according to manufacturer's instructions or after treating the acid-etched dentin with a 3 wt% potassium oxalate gel. The results were expressed as a percentage of maximum permeability values. Impressions and epoxy resin replicas from the crown segments were produced for SEM examination. RESULTS None of the adhesives were able to eliminate the fluid flow through dentin. Two-way ANOVA revealed that the application of potassium oxalate prior to the bonding procedures was the most effective technique in reducingthe dentin permeability (p < 0.05), regardless of the adhesive used. SEM micrographs showed that transudation of dentinal fluid could be identified on the surfaces of all replicas. CONCLUSION The use of potassium oxalate gel was effective in reducing the permeability of bonded dentin.
Collapse
|
42
|
Waring WS, Evans LE, Kirkpatrick CT. Glycolysis inhibitors negatively bias blood glucose measurements: potential impact on the reported prevalence of diabetes mellitus. J Clin Pathol 2007; 60:820-3. [PMID: 17596547 PMCID: PMC1995804 DOI: 10.1136/jcp.2006.039925] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [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: 11/04/2022]
Abstract
BACKGROUND Blood glucose concentrations are essential in defining diabetes mellitus. Recent guidelines advocate either of two discrete methods for sample collection and processing. One of these involves addition of glycolysis inhibitors, such as sodium fluoride-potassium oxalate (NaF-KOx) to sample collection tubes, whereas the other requires immediate refrigeration and sample separation. AIMS To examine whether the choice of the preanalytical process has any impact on subsequent glucose determinations. METHODS 62 healthy men participated in the study during screening for diabetes. Paired venous blood samples were collected in a serum-gel tube and a tube containing NaF-KOx (both Sarstedt, Leicester, UK). Serum was promptly separated from gel tube samples and refrigerated, whereas NaF-KOx samples were not separated until immediately before analysis. Glucose concentrations were determined using an Olympus AU 2700 analyser incorporating an automated hexokinase method. RESULTS Mean (95% CI) glucose concentration in serum-gel tube samples was 5.2 mmol/l (5.0 to 5.4 mmol/l), whereas the concentration in tubes containing NaF-KOx was 4.9 mmol/l (4.8 to 5.1 mmol/l). A negative bias of 0.23 mmol/l (0.16 to 0.30 mmol/l) and relative negative bias of 4.7 % (3.2% to 6.3%) were observed for samples collected in NaF-KOx tubes, consistent with the combined effects of glycolysis and dilution. CONCLUSIONS Bias associated with the use of NaF-KOx tubes may have a significant impact on the prevalence of fasting hyperglycaemia, according to current diagnostic criteria. The small but significant difference between preanalytical processes should be considered when screening for the presence of diabetes mellitus.
Collapse
Affiliation(s)
- W S Waring
- Clinical Pharmacology Unit, Roche Products, Welwyn Garden City, UK.
| | | | | |
Collapse
|
43
|
Thomas E, von Unruh GE, Hesse A. Influence of a low- and a high-oxalate vegetarian diet on intestinal oxalate absorption and urinary excretion. Eur J Clin Nutr 2007; 62:1090-7. [PMID: 17609696 DOI: 10.1038/sj.ejcn.1602832] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [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: 11/08/2022]
Abstract
OBJECTIVE To compare quantitatively the effect of a low- and a high-oxalate vegetarian diet on intestinal oxalate absorption and urinary excretion. SUBJECTS AND METHODS Eight healthy volunteers (three men and five women, mean age 28.6+/-6.3) were studied. Each volunteer performed the [(13)C(2)]oxalate absorption test thrice on a low-oxalate mixed diet, thrice on a low-oxalate vegetarian diet and thrice on a high-oxalate vegetarian diet. For each test, the volunteers had to adhere to an identical diet and collect their 24-h urines. In the morning of the second day, a capsule containing [(13)C(2)]oxalate was ingested. RESULTS On the low-oxalate vegetarian diet, mean intestinal oxalate absorption and urinary oxalate excretion increased significantly to 15.8+/-2.9% (P=0.012) and 0.414+/-0.126 mmol/day (P=0.012), compared to the mixed diet. On the high-oxalate vegetarian diet, oxalate absorption (12.5+/-4.6%, P=0.161) and urinary excretion (0.340+/-0.077 mmol/day, P=0.093) did not change significantly, compared to the mixed diet. CONCLUSIONS A vegetarian diet can only be recommended for calcium oxalate stone patients, if the diet (1) contains the recommended amounts of divalent cations such as calcium and its timing of ingestion to a meal rich in oxalate is considered and (2) excludes foodstuffs with a high content of nutritional factors, such as phytic acid, which are able to chelate calcium.
Collapse
Affiliation(s)
- E Thomas
- Department of Urology, University of Bonn, Bonn, Germany.
| | | | | |
Collapse
|
44
|
Schillinger W, Teucher N, Sossalla S, Kettlewell S, Werner C, Raddatz D, Elgner A, Tenderich G, Pieske B, Ramadori G, Schöndube FA, Kögler H, Kockskämper J, Maier LS, Schwörer H, Smith GL, Hasenfuss G. Negative inotropy of the gastric proton pump inhibitor pantoprazole in myocardium from humans and rabbits: evaluation of mechanisms. Circulation 2007; 116:57-66. [PMID: 17576869 DOI: 10.1161/circulationaha.106.666008] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Proton pump inhibitors are used extensively for acid-related gastrointestinal diseases. Their effect on cardiac contractility has not been assessed directly. METHODS AND RESULTS Under physiological conditions (37 degrees C, pH 7.35, 1.25 mmol/L Ca2+), there was a dose-dependent decrease in contractile force in ventricular trabeculae isolated from end-stage failing human hearts superfused with pantoprazole. The concentration leading to 50% maximal response was 17.3+/-1.3 microg/mL. Similar observations were made in trabeculae from human atria, normal rabbit ventricles, and isolated rabbit ventricular myocytes. Real-time polymerase chain reaction demonstrated the expression of gastric H+/K+-adenosine triphosphatase in human and rabbit myocardium. However, measurements with BCECF-loaded rabbit trabeculae did not reveal any significant pantoprazole-dependent changes of pH(i). Ca2+ transients recorded from field-stimulated fluo 3-loaded myocytes (F/F0) were significantly depressed by 10.4+/-2.1% at 40 microg/mL. Intracellular Ca2+ fluxes were assessed in fura 2-loaded, voltage-clamped rabbit ventricular myocytes. Pantoprazole (40 microg/mL) caused an increase in diastolic [Ca2+]i by 33+/-12%, but peak systolic [Ca2+]i was unchanged, resulting in a decreased Ca2+ transient amplitude by 25+/-8%. The amplitude of the L-type Ca2+ current (I(Ca,L)) was reduced by 35+/-5%, and sarcoplasmic reticulum Ca2+ content was reduced by 18+/-6%. Measurements of oxalate-supported sarcoplasmic reticulum Ca2+ uptake in permeabilized cardiomyocytes indicated that pantoprazole decreased Ca2+ sensitivity (Kd) of sarcoplasmic reticulum Ca2+ adenosine triphosphatase: control, Kd=358+/-15 nmol/L; 40 microg/mL pantoprazole, Kd=395+/-12 nmol/L (P<0.05). Pantoprazole also acted on cardiac myofilaments to reduced Ca2+-activated force. CONCLUSIONS Pantoprazole depresses cardiac contractility in vitro by depression of Ca2+ signaling and myofilament activity. In view of the extensive use of this agent, the effects should be evaluated in vivo.
Collapse
Affiliation(s)
- Wolfgang Schillinger
- Herzzentrum, Kardiologie und Pneumologie, Georg-August Universitaet Goettingen, Robert-Koch Strasse 40, 37099 Goettingen, Germany.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
45
|
Abstract
This paper reports a comparative study of the antioxidative effects of black and green tea extracts in sodium oxalate-challenged rats. A dose of 10 mg/kg of body weight of sodium oxalate was used to induce lipid peroxidation in vivo. Rats treated with sodium oxalate had 42.06 +/- 3.10 nM/hour, 45.39 +/- 9.75 mg/100 mL, 10.95 +/- 1.52%, 15.95 +/- 3.19 mg/dL, 112.25 +/- 5.15 mg/dL, 59.21 +/- 2.95 IU, 39.55 +/- 2.51 IU, and 150.62 +/- 9.62 KA/unit for serum levels of malondialdehyde, reduced ascorbic acid, catalase, cholesterol, phospholipid, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP), respectively. These values are significantly (P < .05) different from values obtained from normal rats. Rats pretreated with 100 mg/kg of body weight of green tea had 27.59 +/- 3.56 nM/hour, 79.11 +/- 5.13 mg/100 mL, 4.23 +/- 0.36%, 50.09 +/- 5.24 mg/dL, 97.58 +/- 4.73 mg/dL, 23.10 +/- 1.59 IU, 31.14 +/- 1.26 IU, and 96.48 +/- 2.36 KA/unit for serum levels of malondialdehyde, reduced ascorbic acid, catalase, cholesterol, phospholipid, AST, ALT, and ALP, respectively, compared with 37.28 +/- 2.07 nM/hour, 72.62 +/- 2.10 mg/100 mL, 6.23 +/- 1.52%, 37.25 +/- 2.84 mg/dL, 78.05 +/- 2.36 mg/dL, 36.08 +/- 1.80 IU, 29.00 +/- 3.02 IU, and 109.23 +/- 6.32 KA/unit recorded for the same parameters in rats treated with black tea. The cholesterol to phospholipid ratio was increased from 0.14 +/- 0.04 in control rats to 0.47 +/- 0.02 and 0.51 +/- 0.01 by black and green tea extracts, respectively. These results suggest that tea extracts have antioxidant properties and that green tea extract is more potent.
Collapse
Affiliation(s)
- O O Ojo
- Chevron Biotechnology Centre, Federal University of Technology, Yola, Nigeria.
| | | | | |
Collapse
|
46
|
Santiago SL, Pereira JC, Martineli ACBF. Effect of commercially available and experimental potassium oxalate-based dentin desensitizing agents in dentin permeability: influence of time and filtration system. Braz Dent J 2007; 17:300-5. [PMID: 17262143 DOI: 10.1590/s0103-64402006000400007] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2005] [Accepted: 04/11/2005] [Indexed: 11/22/2022] Open
Abstract
This study evaluated the influence of time after application of oxalate solutions in reducing dentin hydraulic conductance. Fifty dentin discs were obtained from extracted human third molars and assigned to 5 groups (n=10), according to the desensitizing agent used: Group I: OxaGel; Group II: experimental agent DD-1: Group III: experimental agent DD-2. In Groups IV and V, a placebo gel and deionized water were used as control, respectively. The agents were applied for 3 min, washed out and the hydraulic conductance was measured immediately and at 5-, 15- and 30-min intervals, and after acid etching. Data were analyzed statistically by two-way ANOVA and Duncan's test at 5% significance level. Groups I, II and III did not differ significantly from each other in any of the time intervals (p>0.05). Likewise, Groups IV and V were statistically similar to each other (p>0.05). The active agents reduced significantly dentin permeability in comparison to control groups (p<0.05). Dentin permeability measured in vitro decreased significantly with time regardless of the agent applied (either active or control agents). The results of Group V, in which no dentin desensitizing agent was employed, indicates that the assessment of dentin permeability by this method must be interpreted with caution.
Collapse
Affiliation(s)
- Sérgio Lima Santiago
- Department of Restorative Dentistry, School of Pharmacy, Dentistry and Nursing, Federal University of Ceara, Rua Bento Albuquerque 685/702, 61080-090 Fortaleza, CE, Brazil.
| | | | | |
Collapse
|
47
|
Abstract
Ionizing radiation induces the production of reactive oxygen species, which play an important causative role in apoptotic cell death. Recently, we demonstrated that the control of mitochondrial redox balance and the cellular defense against oxidative damage are primary functions of mitochondrial NADP(+)-dependent isocitrate dehydrogenase (IDPm) by supplying NADPH for antioxidant systems. In this paper, we demonstrate that modulation of IDPm activity in the kidneys of mice regulates ionizing radiation-induced apoptosis. When oxalomalate, a competitive inhibitor of IDPm, was administered to mice, inhibition of IDPm and enhanced susceptibility of apoptosis reflected by DNA fragmentation, the changes in mitochondria function, and the modulation of apoptotic marker proteins were observed upon exposure to 2 Gy of gamma-irradiation. We also observed a significant difference in the mitochondrial redox status between the kidneys of the control and the oxalomalate-administered mice. This study indicates that IDPm may play an important role in regulating the apoptosis induced by ionizing radiation, presumably, through acting as an antioxidant enzyme.
Collapse
Affiliation(s)
- Jin Hyup Lee
- School of Life Sciences and Biotechnology, College of Natural Sciences, Kyungpook National University, Taegu 702-701, Korea
| | | |
Collapse
|
48
|
Abstract
AbstractClin Chem Lab Med 2007;45:1299–304.
Collapse
Affiliation(s)
- A Wayne Jones
- Department of Forensic Genetics and Forensic Chemistry, National Board of Forensic Medicine, Linköping, Sweden.
| |
Collapse
|
49
|
Irace C, Esposito G, Maffettone C, Rossi A, Festa M, Iuvone T, Santamaria R, Sautebin L, Carnuccio R, Colonna A. Oxalomalate affects the inducible nitric oxide synthase expression and activity. Life Sci 2006; 80:1282-91. [PMID: 17257628 DOI: 10.1016/j.lfs.2006.12.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [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: 03/06/2006] [Revised: 12/07/2006] [Accepted: 12/15/2006] [Indexed: 11/30/2022]
Abstract
Inducible nitric oxide synthase (iNOS) is an homodimeric enzyme which produces large amounts of nitric oxide (NO) in response to inflammatory stimuli. Several factors affect the synthesis and catalytic activity of iNOS. Particularly, dimerization of NOS monomers is promoted by heme, whereas an intracellular depletion of heme and/or L-arginine considerably decreases NOS resistance to proteolysis. In this study, we found that oxalomalate (OMA, oxalomalic acid, alpha-hydroxy-beta-oxalosuccinic acid), an inhibitor of both aconitase and NADP-dependent isocitrate dehydrogenase, inhibited nitrite production and iNOS protein expression in lipopolysaccharide (LPS)-activated J774 macrophages, without affecting iNOS mRNA content. Furthermore, injection of OMA precursors to LPS-stimulated rats also decreased nitrite production and iNOS expression in isolated peritoneal macrophages. Interestingly, alpha-ketoglutarate or succinyl-CoA administration reversed OMA effect on NO production, thus correlating NO biosynthesis with the anabolic capacity of Krebs cycle. When protein synthesis was blocked by cycloheximide in LPS-activated J774 cells treated with OMA, iNOS protein levels, evaluated by Western blot analysis and (35)S-metabolic labelling, were decreased, suggesting that OMA reduces iNOS biosynthesis and induces an increase in the degradation rate of iNOS protein. Moreover, we showed that OMA inhibits the activity of the iNOS from lung of LPS-treated rats by enzymatic assay. Our results, demonstrating that OMA acts regulating synthesis, catalytic activity and degradation of iNOS, suggest that this compound might have a potential role in reducing the NO overproduction occurring in some pathological conditions.
Collapse
Affiliation(s)
- Carlo Irace
- Dipartimento di Farmacologia Sperimentale, Università di Napoli Federico II, via D. Montesano 49, 80131-Napoli, Italy
| | | | | | | | | | | | | | | | | | | |
Collapse
|
50
|
Puntel RL, Roos DH, Paixão MW, Braga AL, Zeni G, Nogueira CW, Rocha JBT. Oxalate modulates thiobarbituric acid reactive species (TBARS) production in supernatants of homogenates from rat brain, liver and kidney: effect of diphenyl diselenide and diphenyl ditelluride. Chem Biol Interact 2006; 165:87-98. [PMID: 17188671 DOI: 10.1016/j.cbi.2006.11.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2006] [Revised: 11/03/2006] [Accepted: 11/09/2006] [Indexed: 10/23/2022]
Abstract
The aim of this paper was to investigate the mechanism(s) involved in the sodium oxalate pro-oxidative activity in vitro and the potential protection by diphenyl diselenide ((PhSe)(2)) and diphenyl ditelluride ((PhTe)(2)) using supernatants of homogenates from brain, liver and kidney. Oxalate causes a significant increase in the TBARS (thiobarbituric acid reactive species) production up to 4mmol/l and it had antioxidant activity from 8 to 16mmol/l in the brain and liver. Oxalate had no effect in kidney homogenates. The difference among tissues may be related to the formation of insoluble crystal of oxalate in kidney, but not in liver and brain homogenates. (PhSe)(2) and (PhTe)(2) reduced both basal and oxalate-induced TBARS in rat brain homogenates, whereas in liver homogenates they were antioxidant only on oxalate-induced TBARS production. (PhSe)(2) showed a modest effect on renal TBARS production, whereas (PhTe)(2) did not modulate TBARS in kidney preparations. Oxalate at 2mmol/l did not change deoxyribose degradation induced by Fe(2+) plus H(2)O(2), whereas at 20mmol/l it significantly prevents its degradation. Oxalate (up to 4mmol/l) did not alter iron (10micromol/l)-induced TBARS production in the brain preparations, whereas at 8mmol/l onwards it prevents iron effect. In liver preparations, oxalate amplifies iron pro-oxidant activity up to 4mmol/l, preventing iron-induced TBARS production at 16mmol/l onwards. These results support the antioxidant effect of organochalcogens against oxalate-induced TBARS production. In addition, our results suggest that oxalate pro- and antioxidant activity in vitro could be related to its interactions with iron ions.
Collapse
Affiliation(s)
- Robson Luiz Puntel
- Departamento de Química, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Campus UFSM, Santa Maria, RS 97105-900, Brazil
| | | | | | | | | | | | | |
Collapse
|