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Glycogen-Endoplasmic Reticulum Connection in the Liver. Int J Mol Sci 2023; 24:ijms24021074. [PMID: 36674588 PMCID: PMC9862463 DOI: 10.3390/ijms24021074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 12/04/2022] [Accepted: 12/27/2022] [Indexed: 01/08/2023] Open
Abstract
Glycogen, the branched polymer of glucose is found mainly in the liver and muscle in mammals. Along with several other proteins, glycogen forms separate cellular organelles, and particles in cells. Glycogen particles in the liver have a special metabolic and also regulatory connection to the intracellular endomembrane system, particularly the endoplasmic reticulum. This connection is part of the organelle homeostasis in hepatocytes and forms a "glycogenoreticular system". The actual size of hepatic glycogen stores and the rate of glycogenolysis determines several essential liver-specific metabolic processes, such as glucose secretion for the maintenance of blood glucose levels or the glucuronidation of certain vital endo-, and xenobiotics, and are also related to liver antioxidant defense. In starvation, and in certain physiological and pathological states, where glycogen stores are depleted, functions of the glycogenoreticular system are altered. The starvation-induced depletion of hepatic glycogen content changes the biotransformation of various endo- and xenobiotics. This can be observed especially in acute DILI (drug-induced liver injury) due to paracetamol overdose, which is the most common cause of acute liver failure in the West.
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Zargar S, Wani TA. Protective Role of Quercetin in Carbon Tetrachloride Induced Toxicity in Rat Brain: Biochemical, Spectrophotometric Assays and Computational Approach. Molecules 2021; 26:molecules26247526. [PMID: 34946608 PMCID: PMC8709345 DOI: 10.3390/molecules26247526] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 12/04/2021] [Accepted: 12/09/2021] [Indexed: 01/14/2023] Open
Abstract
Carbon tetrachloride (CCL4) induces oxidative stress by free radical toxicities, inflammation, and neurotoxicity. Quercetin (Q), on the other hand, has a role as anti-inflammatory, antioxidant, antibacterial, and free radical-scavenging. This study explored protection given by quercetin against CCL4 induced neurotoxicity in rats at given concentrations. Male Wistar rats were divided into four groups Group C: control group; Group CCL4: given a single oral dose of 1 mL/kg bw CCL4; Group Q: given a single i.p injection of 100 mg/kg bw quercetin; and Group Q + CCL4: given a single i.p injection of 100 mg/kg bw quercetin before two hours of a single oral dose of 1 mL/kg bw CCL4. The results from brain-to-body weight ratio, morphology, lipid peroxidation, brain urea, ascorbic acid, reduced glutathione, sodium, and enzyme alterations (aspartate aminotransferase (AST), alanine aminotransferase (ALT), catalase, and superoxide dismutase) suggested alterations by CCL4 and a significant reversal of these parameters by quercetin. In silico analysis of quercetin with various proteins was conducted to understand the molecular mechanism of its protection. The results identified by BzScore4 D showed moderate binding between quercetin and the following receptors: glucocorticoids, estrogen beta, and androgens and weak binding between quercetin and the following proteins: estrogen alpha, Peroxisome proliferator-activated receptors (PPARγ), Herg k+ channel, Liver x, mineralocorticoid, progesterone, Thyroid α, and Thyroid β. Three-dimensional/four-dimensional visualization of binding modes of quercetin with glucocorticoids, estrogen beta, and androgen receptors was performed. Based on the results, a possible mechanism is hypothesized for quercetin protection against CCL4 toxicity in the rat brain.
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Affiliation(s)
- Seema Zargar
- Department of Biochemistry, College of Science, King Saud University, Riyadh 11495, Saudi Arabia
- Correspondence:
| | - Tanveer A. Wani
- Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia;
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Fujii J. Ascorbate is a multifunctional micronutrient whose synthesis is lacking in primates. J Clin Biochem Nutr 2021; 69:1-15. [PMID: 34376908 PMCID: PMC8325764 DOI: 10.3164/jcbn.20-181] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Accepted: 12/07/2020] [Indexed: 02/06/2023] Open
Abstract
Ascorbate (vitamin C) is an essential micronutrient in primates, and exhibits multiple physiological functions. In addition to antioxidative action, ascorbate provides reducing power to α-ketoglutarate-dependent non-heme iron dioxygenases, such as prolyl hydroxylases. Demethylation of histones and DNA with the aid of ascorbate results in the reactivation of epigenetically silenced genes. Ascorbate and its oxidized form, dehydroascorbate, have attracted interest in terms of their roles in cancer therapy. The last step in the biosynthesis of ascorbate is catalyzed by l-gulono-γ-lactone oxidase whose gene Gulo is commonly mutated in all animals that do not synthesize ascorbate. One common explanation for this deficiency is based on the increased availability of ascorbate from foods. In fact, pathways for ascorbate synthesis and the detoxification of xenobiotics by glucuronate conjugation share the metabolic processes up to UDP-glucuronate, which prompts another hypothesis, namely, that ascorbate-incompetent animals might have developed stronger detoxification systems in return for their lack of ability to produce ascorbate, which would allow them to cope with their situation. Here, we overview recent advances in ascorbate research and propose that an enhanced glucuronate conjugation reaction may have applied positive selection pressure on ascorbate-incompetent animals, thus allowing them to dominate the animal kingdom.
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Affiliation(s)
- Junichi Fujii
- Department of Biochemistry and Molecular Biology, Graduate School of Medical Science, Yamagata University, Yamagata 990-9585, Japan
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Mandl J, Bánhegyi G. The ER - Glycogen Particle - Phagophore Triangle: A Hub Connecting Glycogenolysis and Glycophagy? Pathol Oncol Res 2018; 24:821-826. [PMID: 29981013 DOI: 10.1007/s12253-018-0446-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 06/28/2018] [Indexed: 12/27/2022]
Abstract
Glycogen particle is an intracellular organelle, which serves as a carbohydrate reserve in various cells. The function of glycogen is not entirely known in several cell types. Glycogen can be mobilized for different purposes, which can be related to cellular metabolic needs, intracellular redox state, metabolic state of the whole organism depending on regulatory aspects and also on cell functions. Essentially there are two different ways of glycogen degradation localized in different cellular organelles: glycogenolysis or lysosomal breakdown by acid alpha-glucosidase. While glycogenolysis occurs in glycogen particles connected to endoplasmic reticulum membrane, glycogen particles can be also combined with phagophores forming autophagosomes. A subdomain of the endoplasmic reticulum membrane - omegasomes - are the sites for phagophore formation. Thus, three organelles, the endoplasmic reticulum, the phagophore and the glycogen particle forms a triangle in which glycogen degradation occurs. The physiological significance, molecular logic and regulation of the two different catabolic paths are summarized and discussed with special aspect on the role of glycogen particles in intracellular organelle homeostasis and on molecular pathology of the cell. Pathological aspects and some diseases connected to the two different degradation pathways of glycogen particles are also detailed.
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Affiliation(s)
- József Mandl
- Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Budapest, Hungary.
| | - Gábor Bánhegyi
- Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Budapest, Hungary
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Ohta Y, Yashiro K, Ohashi K, Horikoshi Y, Kusumoto C, Matsura T. Compound 48/80, a mast cell degranulator, causes oxidative damage by enhancing vitamin C synthesis via reduced glutathione depletion and lipid peroxidation through neutrophil infiltration in rat livers. J Clin Biochem Nutr 2017; 60:187-198. [PMID: 28584400 PMCID: PMC5453024 DOI: 10.3164/jcbn.16-89] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 12/19/2016] [Indexed: 01/14/2023] Open
Abstract
In this study, we examined whether compound 48/80 (C48/80), a mast cell degranulator, causes hepatic oxidative damage in rats. Serum and liver biochemical parameters were determined 0.5, 3 or 6 h after a single treatment with C48/80 (0.75 mg/kg). Serum histamine and serotonin levels increased 0.5 h after C48/80 treatment but diminished thereafter. Increases in serum vitamin C (VC) and transaminases and hepatic hydrogen peroxide, lipid peroxide, and myeloperoxidase levels and a decrease in hepatic reduced glutathione level occurred 0.5 h after C48/80 treatment and further proceeded at 3 h, but these changes diminished at 6 h. Serum lipid peroxide and hepatic VC levels increased 3 h after C48/80 treatment. Hepatic glycogen level decreased 0.5 h after C48/80 treatment and further decreased at 3 h. Pre-administered ketotifen diminished all these changes found at 3 h after treatment, while pre-administered NPC 14686 diminished these changes except changes in serum histamine and serotonin levels. Hepatocellular apoptosis observed at 3 h after C48/80 treatment was attenuated by pre-administered ketotifen and NPC 14686. These results indicate that C48/80 causes oxidative damage by enhancing VC synthesis via reduced glutathione depletion-dependent glycogenolysis and lipid peroxidation through neutrophil infiltration following mast cell degranulation in rat livers.
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Affiliation(s)
- Yosihiji Ohta
- Department of Chemistry, Fujita Health University School of Medicine, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi 470-1192, Japan
| | - Koji Yashiro
- Department of Chemistry, Fujita Health University School of Medicine, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi 470-1192, Japan
| | - Koji Ohashi
- Department of Clinical Biochemistry, Faculty of Medical Chemistry, Fujita Health University School of Health Sciences, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi 470-1192, Japan
| | - Yosuke Horikoshi
- Division of Medical Biochemistry, Department of Pathophysiological and Therapeutic Science, Totorri University Faculty of Medicine, 86 Nishimachi, Yonago, Tottori 683-8503, Japan
| | - Chiaki Kusumoto
- Department of Gastroenterology, Nippon Kokan Fukuyama Hospital, 1844 Tsunoshita, Daimon, Fukuyama, Hiroshima 721-0927, Japan
| | - Tatsuya Matsura
- Division of Medical Biochemistry, Department of Pathophysiological and Therapeutic Science, Totorri University Faculty of Medicine, 86 Nishimachi, Yonago, Tottori 683-8503, Japan
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Nault R, Fader KA, Ammendolia DA, Dornbos P, Potter D, Sharratt B, Kumagai K, Harkema JR, Lunt SY, Matthews J, Zacharewski T. Dose-Dependent Metabolic Reprogramming and Differential Gene Expression in TCDD-Elicited Hepatic Fibrosis. Toxicol Sci 2016; 154:253-266. [PMID: 27562557 DOI: 10.1093/toxsci/kfw163] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
We have previously shown that in response to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-elicited NAFLD progression, central carbon, glutaminolysis, and serine/folate metabolism are reprogrammed to support NADPH production and ROS defenses. To further investigate underlying dose-dependent responses associated with TCDD-induced fibrosis, female C57BL/6 mice were gavaged with TCDD every 4 days (d) for 28 d or 92 d. RNA-Seq, ChIP-Seq (2 h), and 28 d metabolomic (urine, serum, and hepatic extract) analyses were conducted with complementary serum marker assessments at 92 d. Additional vehicle and 30 µg/kg treatment groups were allowed to recover for 36 d following the 92-d treatment regimen to examine recovery from TCDD-elicited fibrosis. Histopathology revealed dose-dependent increases in hepatic fat accumulation, inflammation, and periportal collagen deposition at 92 days, with increased fibrotic severity in the recovery group. Serum proinflammatory and profibrotic interleukins-1β, -2, -4, -6, and -10, as well as TNF-α and IFN-γ, exhibited dose-dependent induction. An increase in glucose tolerance was observed with a concomitant 3.0-fold decrease in hepatic glycogen linked to increased ascorbic acid biosynthesis and proline metabolism, consistent with increased fibrosis. RNA-Seq identified differential expression of numerous matrisome genes including an 8.8-fold increase in Tgfb2 indicating myofibroblast activation. Further analysis suggests reprogramming of glycogen, ascorbic acid, and amino acid metabolism in support of collagen deposition and the use of proline as a substrate for ATP production via the proline cycle. In summary, we demonstrate that glycogen, ascorbic acid, and amino acid metabolism are also reorganized to support remodeling of the extracellular matrix, progressing to hepatic fibrosis in response to chronic injury from TCDD.
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Affiliation(s)
- Rance Nault
- Biochemistry & Molecular Biology.,Institute for Integrative Toxicology
| | - Kelly A Fader
- Biochemistry & Molecular Biology.,Institute for Integrative Toxicology
| | | | - Peter Dornbos
- Biochemistry & Molecular Biology.,Institute for Integrative Toxicology
| | - Dave Potter
- Wellington Laboratories, Inc., Guelph, Ontario, Canada
| | | | - Kazuyoshi Kumagai
- Pathology & Diagnostic Investigation, Michigan State University, East Lansing, Michigan
| | - Jack R Harkema
- Institute for Integrative Toxicology.,Pathology & Diagnostic Investigation, Michigan State University, East Lansing, Michigan
| | | | - Jason Matthews
- Department of Nutrition, University of Oslo, Oslo 0316, Norway
| | - Tim Zacharewski
- Biochemistry & Molecular Biology; .,Institute for Integrative Toxicology
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7
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Landry GM, Dunning CL, Abreo F, Latimer B, Orchard E, McMartin KE. Diethylene glycol-induced toxicities show marked threshold dose response in rats. Toxicol Appl Pharmacol 2014; 282:244-51. [PMID: 25545985 DOI: 10.1016/j.taap.2014.12.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 12/15/2014] [Accepted: 12/18/2014] [Indexed: 11/16/2022]
Abstract
Diethylene glycol (DEG) exposure poses risks to human health because of widespread industrial use and accidental exposures from contaminated products. To enhance the understanding of the mechanistic role of metabolites in DEG toxicity, this study used a dose response paradigm to determine a rat model that would best mimic DEG exposure in humans. Wistar and Fischer-344 (F-344) rats were treated by oral gavage with 0, 2, 5, or 10g/kg DEG and blood, kidney and liver tissues were collected at 48h. Both rat strains treated with 10g/kg DEG had equivalent degrees of metabolic acidosis, renal toxicity (increased BUN and creatinine and cortical necrosis) and liver toxicity (increased serum enzyme levels, centrilobular necrosis and severe glycogen depletion). There was no liver or kidney toxicity at the lower DEG doses (2 and 5g/kg) regardless of strain, demonstrating a steep threshold dose response. Kidney diglycolic acid (DGA), the presumed nephrotoxic metabolite of DEG, was markedly elevated in both rat strains administered 10g/kg DEG, but no DGA was present at 2 or 5g/kg, asserting its necessary role in DEG-induced toxicity. These results indicate that mechanistically in order to produce toxicity, metabolism to and significant target organ accumulation of DGA are required and that both strains would be useful for DEG risk assessments.
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Affiliation(s)
- Greg M Landry
- Department of Pharmacology, Toxicology, & Neuroscience, Louisiana State University Health Sciences Center, Shreveport, LA, United States.
| | - Cody L Dunning
- Department of Pharmacology, Toxicology, & Neuroscience, Louisiana State University Health Sciences Center, Shreveport, LA, United States.
| | - Fleurette Abreo
- Department of Pathology, Louisiana State University Health Sciences Center, Shreveport, LA, United States.
| | - Brian Latimer
- Department of Pharmacology, Toxicology, & Neuroscience, Louisiana State University Health Sciences Center, Shreveport, LA, United States.
| | - Elysse Orchard
- Department of Pharmacology, Toxicology, & Neuroscience, Louisiana State University Health Sciences Center, Shreveport, LA, United States; Division of Animal Resources, Louisiana State University Health Sciences Center, Shreveport, LA, United States.
| | - Kenneth E McMartin
- Department of Pharmacology, Toxicology, & Neuroscience, Louisiana State University Health Sciences Center, Shreveport, LA, United States.
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Pogge DJ, Lonergan SM, Hansen SL. Influence of supplementing vitamin C to yearling steers fed a high sulfur diet during the finishing period on meat color, tenderness and protein degradation, and fatty acid profile of the longissimus muscle. Meat Sci 2014; 97:419-27. [PMID: 24769141 DOI: 10.1016/j.meatsci.2014.02.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Revised: 01/22/2014] [Accepted: 02/28/2014] [Indexed: 10/25/2022]
Abstract
The objective was to determine the influence of vitamin C (VC) supplemented for approximately 102 d during the finishing period on color, tenderness, and fatty acid profile of longissimus thoracis (LT; n=136) from steers fed a 0.55% sulfur diet. Treatments included 4 supplemental VC concentrations: 1) 0 (CON), 2) 5 (5VC), 3) 10 (10VC), or 4) 20 (20VC) gVC·h(-1)∙d(-1) in a common diet. Increasing supplemental VC decreased (P<0.01) L*, but increased (P<0.01) vitamin E and tended to increase (P≤0.07) calcium and iron content of steaks. No VC (P≥0.25) effect was noted for WBSF, calpain-1 autolysis, troponin T degradation, or most fatty acid profiles. A quadratic effect (P≤0.03) was observed for cholesterol and CLA content of LT. Under the conditions of our study, supplementing VC to steers fed a 0.55% sulfur diet late in the finishing period did not influence color or tenderness, but increased the vitamin E content.
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Affiliation(s)
- Danielle J Pogge
- Department of Animal Science and Interdepartmental Graduate Program in Nutritional Sciences, Iowa State University, Ames, IA 50011, United States
| | - Steven M Lonergan
- Department of Animal Science and Interdepartmental Graduate Program in Nutritional Sciences, Iowa State University, Ames, IA 50011, United States
| | - Stephanie L Hansen
- Department of Animal Science and Interdepartmental Graduate Program in Nutritional Sciences, Iowa State University, Ames, IA 50011, United States.
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Michels AJ, Frei B. Myths, artifacts, and fatal flaws: identifying limitations and opportunities in vitamin C research. Nutrients 2013; 5:5161-92. [PMID: 24352093 PMCID: PMC3875932 DOI: 10.3390/nu5125161] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Revised: 11/23/2013] [Accepted: 11/27/2013] [Indexed: 01/01/2023] Open
Abstract
Research progress to understand the role of vitamin C (ascorbic acid) in human health has been slow in coming. This is predominantly the result of several flawed approaches to study design, often lacking a full appreciation of the redox chemistry and biology of ascorbic acid. In this review, we summarize our knowledge surrounding the limitations of common approaches used in vitamin C research. In human cell culture, the primary issues are the high oxygen environment, presence of redox-active transition metal ions in culture media, and the use of immortalized cell lines grown in the absence of supplemental ascorbic acid. Studies in animal models are also limited due to the presence of endogenous ascorbic acid synthesis. Despite the use of genetically altered rodent strains lacking synthesis capacity, there are additional concerns that these models do not adequately recapitulate the effects of vitamin C deprivation and supplementation observed in humans. Lastly, several flaws in study design endemic to randomized controlled trials and other human studies greatly limit their conclusions and impact. There also is anecdotal evidence of positive and negative health effects of vitamin C that are widely accepted but have not been substantiated. Only with careful attention to study design and experimental detail can we further our understanding of the possible roles of vitamin C in promoting human health and preventing or treating disease.
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Affiliation(s)
- Alexander J Michels
- Linus Pauling Institute, 307 Linus Pauling Science Center, Oregon State University, Corvallis, OR 97331, USA.
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10
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Gautam R, Chandrasekar B, Deobagkar-Lele M, Rakshit S, Kumar B. N. V, Umapathy S, Nandi D. Identification of early biomarkers during acetaminophen-induced hepatotoxicity by fourier transform infrared microspectroscopy. PLoS One 2012; 7:e45521. [PMID: 23029070 PMCID: PMC3446881 DOI: 10.1371/journal.pone.0045521] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Accepted: 08/20/2012] [Indexed: 01/15/2023] Open
Abstract
Acetaminophen is a widely prescribed drug used to relieve pain and fever; however, it is a leading cause of drug-induced liver injury and a burden on public healthcare. In this study, hepatotoxicity in mice post oral dosing of acetaminophen was investigated using liver and sera samples with Fourier Transform Infrared microspectroscopy. The infrared spectra of acetaminophen treated livers in BALB/c mice show decrease in glycogen, increase in amounts of cholesteryl esters and DNA respectively. Rescue experiments using L-methionine demonstrate that depletion in glycogen and increase in DNA are abrogated with pre-treatment, but not post-treatment, with L-methionine. This indicates that changes in glycogen and DNA are more sensitive to the rapid depletion of glutathione. Importantly, analysis of sera identified lowering of glycogen and increase in DNA and chlolesteryl esters earlier than increase in alanine aminotransferase, which is routinely used to diagnose liver damage. In addition, these changes are also observed in C57BL/6 and Nos2−/− mice. There is no difference in the kinetics of expression of these three molecules in both strains of mice, the extent of damage is similar and corroborated with ALT and histological analysis. Quantification of cytokines in sera showed increase upon APAP treatment. Although the levels of Tnfα and Ifnγ in sera are not significantly affected, Nos2−/− mice display lower Il6 but higher Il10 levels during this acute model of hepatotoxicity. Overall, this study reinforces the growing potential of Fourier Transform Infrared microspectroscopy as a fast, highly sensitive and label-free technique for non-invasive diagnosis of liver damage. The combination of Fourier Transform Infrared microspectroscopy and cytokine analysis is a powerful tool to identify multiple biomarkers, understand differential host responses and evaluate therapeutic regimens during liver damage and, possibly, other diseases.
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Affiliation(s)
- Rekha Gautam
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, India
| | | | | | - Srabanti Rakshit
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Vinay Kumar B. N.
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, India
| | - Siva Umapathy
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, India
- * E-mail: (DN); (SU)
| | - Dipankar Nandi
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
- * E-mail: (DN); (SU)
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De Bona KS, Bellé LP, Bittencourt PER, Bonfanti G, Cargnelluti LO, Pimentel VC, Ruviaro AR, Schetinger MRC, Emanuelli T, Moretto MB. Erythrocytic enzymes and antioxidant status in people with type 2 diabetes: beneficial effect of Syzygium cumini leaf extract in vitro. Diabetes Res Clin Pract 2011; 94:84-90. [PMID: 21737173 DOI: 10.1016/j.diabres.2011.06.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Revised: 05/25/2011] [Accepted: 06/06/2011] [Indexed: 11/19/2022]
Abstract
The aim of the present study was to investigate the effects of Syzygium cumini leaf extract (ASc), on Adenosine deaminase (ADA) and Acetylcholinesterase (AChE) activities, and also on oxidative stress parameters in erythrocytes hemolysates (RBCs) and erythrocytes membranes (ghosts) from type 2 diabetics patients (Type 2 DM) under in vitro conditions. Non protein thiol groups (NP-SH), AChE, Catalase (CAT) and Superoxide Dismutase (SOD) activities were measure in RBCs. Further, ADA activity, Thiobarbituric Acid-Reactive Substances (TBARS) levels and protein thiol groups (P-SH) were estimated in ghosts. Also, P-SH and Vitamin C (VIT C) were measure in plasma sample. The results demonstrated that ADA and AChE activities, besides TBARS levels were higher in erythrocytes of Type 2 DM, while SOD activity and NP-SH levels were decreased when compared to control group. ASc, in vitro, reduced ADA and AChE activities and some parameters of oxidative stress. Furthermore, we observed correlations between VIT C and P-SH levels, ADA activity and P-SH levels, as well as NP-SH and TBARS levels in diabetics. The results suggest that ASc in vitro is able to promote the reduction of inflammation and oxidative stress parameters, and act against biochemical changes occurring in Diabetes mellitus (DM).
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Affiliation(s)
- Karine Santos De Bona
- Postgraduate Program in Pharmaceutical Sciences, Health Science Centre, Federal University of Santa Maria (UFSM), Santa Maria, RS, Brazil
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Bando K, Kunimatsu T, Sakai J, Kimura J, Funabashi H, Seki T, Bamba T, Fukusaki E. GC-MS-based metabolomics reveals mechanism of action for hydrazine induced hepatotoxicity in rats. J Appl Toxicol 2010; 31:524-35. [DOI: 10.1002/jat.1591] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Revised: 08/16/2010] [Accepted: 08/16/2010] [Indexed: 11/11/2022]
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Abstract
Although ascorbic acid is an important water-soluble antioxidant and enzyme cofactor in plants and animals, humans and some other species do not synthesize ascorbate due to the lack of the enzyme catalyzing the final step of the biosynthetic pathway, and for them it has become a vitamin. This review focuses on the role of ascorbate in various hydroxylation reactions and in the redox homeostasis of subcellular compartments including mitochondria and endoplasmic reticulum. Recently discovered functions of ascorbate in nucleic acid and histone dealkylation and proteoglycan deglycanation are also summarized. These new findings might delineate a role for ascorbate in the modulation of both pro- and anti-carcinogenic mechanisms. Recent advances and perspectives in therapeutic applications are also reviewed. On the basis of new and earlier observations, the advantages of the lost ability to synthesize ascorbate are pondered. The increasing knowledge of the functions of ascorbate and of its molecular sites of action can mechanistically substantiate a place for ascorbate in the treatment of various diseases.
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Affiliation(s)
- J Mandl
- Department of Medical Chemistry, Molecular Biology and Patobiochemistry, Semmelweis University Budapest, Budapest, Hungary.
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14
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Abstract
Vitamin C, a reducing agent and antioxidant, is a cofactor in reactions catalyzed by Cu(+)-dependent monooxygenases and Fe(2+)-dependent dioxygenases. It is synthesized, in vertebrates having this capacity, from d-glucuronate. The latter is formed through direct hydrolysis of uridine diphosphate (UDP)-glucuronate by enzyme(s) bound to the endoplasmic reticulum membrane, sharing many properties with, and most likely identical to, UDP-glucuronosyltransferases. Non-glucuronidable xenobiotics (aminopyrine, metyrapone, chloretone and others) stimulate the enzymatic hydrolysis of UDP-glucuronate, accounting for their effect to increase vitamin C formation in vivo. Glucuronate is converted to l-gulonate by aldehyde reductase, an enzyme of the aldo-keto reductase superfamily. l-Gulonate is converted to l-gulonolactone by a lactonase identified as SMP30 or regucalcin, whose absence in mice leads to vitamin C deficiency. The last step in the pathway of vitamin C synthesis is the oxidation of l-gulonolactone to l-ascorbic acid by l-gulonolactone oxidase, an enzyme associated with the endoplasmic reticulum membrane and deficient in man, guinea pig and other species due to mutations in its gene. Another fate of glucuronate is its conversion to d-xylulose in a five-step pathway, the pentose pathway, involving identified oxidoreductases and an unknown decarboxylase. Semidehydroascorbate, a major oxidation product of vitamin C, is reconverted to ascorbate in the cytosol by cytochrome b(5) reductase and thioredoxin reductase in reactions involving NADH and NADPH, respectively. Transmembrane electron transfer systems using ascorbate or NADH as electron donors serve to reduce semidehydroascorbate present in neuroendocrine secretory vesicles and in the extracellular medium. Dehydroascorbate, the fully oxidized form of vitamin C, is reduced spontaneously by glutathione, as well as enzymatically in reactions using glutathione or NADPH. The degradation of vitamin C in mammals is initiated by the hydrolysis of dehydroascorbate to 2,3-diketo-l-gulonate, which is spontaneously degraded to oxalate, CO(2) and l-erythrulose. This is at variance with bacteria such as Escherichia coli, which have enzymatic degradation pathways for ascorbate and probably also dehydroascorbate.
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Affiliation(s)
- Carole L Linster
- Université Catholique de Louvain, Christian de Duve Institute of Cellular Pathology, Brussels, Belgium
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15
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Yang CS, Chang SC, Tsai PJ, Chen WY, Kuo JS. Simultaneous Measurement of Ascorbic Acid and Glutathione: Application of Microdialysis and On-Line HPLC With Au/Hg Electrode in Anesthetized Rat Liver. J LIQ CHROMATOGR R T 2006. [DOI: 10.1080/10826079808001263] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- C.-S. Yang
- a Department of Education and Research , Taichung Veterans General Hospital Taichung , Taiwan 407, R. O. C
| | - S.-C. Chang
- b Department of Chemistry , National Tsinghua University , Hsinchu, Taiwan 300, R. O. C
| | - P.-J. Tsai
- a Department of Education and Research , Taichung Veterans General Hospital Taichung , Taiwan 407, R. O. C
| | - W.-Y. Chen
- a Department of Education and Research , Taichung Veterans General Hospital Taichung , Taiwan 407, R. O. C
| | - J.-S. Kuo
- a Department of Education and Research , Taichung Veterans General Hospital Taichung , Taiwan 407, R. O. C
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16
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Bulduk E, Gönül B, Ozer C. Effects of vitamin C on muscle glycogen and oxidative events in experimental diabetes. Mol Cell Biochem 2006; 292:131-7. [PMID: 16758299 DOI: 10.1007/s11010-006-9226-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2005] [Accepted: 05/01/2006] [Indexed: 11/22/2022]
Abstract
UNLABELLED Streptozotocin (STZ) is an agent used in creating experimental diabetes. Varying findings have been reported about the striated muscle glycogen levels in diabetes. In this study, it was planned to observe interaction of vitamin C (AA), of which deficiency has been shown in diabetics, with soleus muscle glycogen levels and oxidative events on STZ-diabetic subjects. MATERIAL AND METHOD In the study, 38 male adult Wistar Albino rats with weights 200 +/- 20 g were used by separating them into four groups: Control, Vitamin C, Diabetes, Diabetes + Vitamin C. Body weights and fasting blood glucose were measured at the beginning and end of the experiment. AA, TBARS, GSH, NOx and glycogen levels of soleus muscles, and AA level of blood were measured. The results were compared using Anova variance and Mann-Whitney U tests. Results showed that AA levels in blood increased with vitamin C administration; AA, GSH and NOx levels in the muscle were low and MDA and glycogen levels were high in diabetics; and that vitamin C in the given dosage partially corrected these values. These results indicate that higher dosage than daily 20 mg/kg Vitamin C is required for being effective on metabolic and oxidizing events in diabetic rats.
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Affiliation(s)
- E Bulduk
- Gazi University Medicine School Physiology Department, Ankara, 06500, Turkey
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17
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Chan TS, Wilson JX, O'Brien PJ. Glycogenolysis is directed towards ascorbate synthesis by glutathione conjugation. Biochem Biophys Res Commun 2004; 317:149-56. [PMID: 15047160 DOI: 10.1016/j.bbrc.2004.03.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2004] [Indexed: 11/29/2022]
Abstract
Using isolated rat hepatocytes we have shown that glutathione (GSH) depletion by glutathione-S-transferase (GST)-catalyzed conjugation with 1-bromoheptane or phorone was accompanied by a significant elevation in ascorbate synthesis. Glycogenolysis was also stimulated without a significant rise in glucose synthesis. Furthermore, when glycogenolysis was stimulated in control hepatocytes by increasing intracellular cAMP levels (with glucagon or dibutyryl cAMP), cellular glucose levels, but not ascorbate levels, increased. These data suggest that GSH depletion can stimulate ascorbate synthesis independently of glucose synthesis and that hepatocytes can direct glycogenolysis towards ascorbate synthesis during GSH conjugation.
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Affiliation(s)
- Tom S Chan
- Faculty of Pharmacy, University of Toronto, 19 Russell St Rm 522, Toronto, Ont, Canada M5S 2S2
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18
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Linster CL, Van Schaftingen E. Rapid stimulation of free glucuronate formation by non-glucuronidable xenobiotics in isolated rat hepatocytes. J Biol Chem 2003; 278:36328-33. [PMID: 12865420 DOI: 10.1074/jbc.m306593200] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Vitamin C synthesis in rat liver is enhanced by several xenobiotics, including aminopyrine and chloretone. The effect of these agents has been linked to induction of enzymes potentially involved in the formation of glucuronate, a precursor of vitamin C. Using isolated rat hepatocytes as a model, we show that a series of agents (aminopyrine, antipyrine, chloretone, clotrimazole, metyrapone, proadifen, and barbital) induced in a few minutes an up to 15-fold increase in the formation of glucuronate, which was best observed in the presence of sorbinil, an inhibitor of glucuronate reductase. They also caused an approximately 2-fold decrease in the concentration of UDP-glucuronate but little if any change in the concentration of UDP-glucose. Depletion of UDP-glucuronate with resorcinol or d-galactosamine markedly decreased the formation of glucuronate both in the presence and in the absence of aminopyrine, confirming the precursor-product relationship between UDP-glucuronate and free glucuronate. Most of the agents did not induce the formation of detectable amounts of glucuronides, indicating that the formation of glucuronate is not due to a glucuronidation-deglucuronidation cycle. With the exception of barbital (which inhibits glucuronate reductase), all of the above mentioned agents also caused an increase in the concentration of ascorbic acid. They had little effect on glutathione concentration, and their effect on glucuronate and vitamin C formation was not mimicked by glutathione-depleting agents such as diamide and buthionine sulfoximine. It is concluded that the stimulation of vitamin C synthesis exerted by some xenobiotics is mediated through a rapid increase in the conversion of UDP-glucuronate to glucuronate, which does not apparently involve a glucuronidation-deglucuronidation cycle.
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Affiliation(s)
- Carole L Linster
- Laboratory of Physiological Chemistry, Université de Louvain and the Christian de Duve Institute of Cellular Pathology, B-1200 Brussels, Belgium
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19
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Affiliation(s)
- Jôzsef Mandl
- Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Budapest, Hungary
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20
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Abstract
One of the major liver functions is the ability of hepatocytes to store glucose in the form of glycogen for various purposes. Beside glucose production and secretion, the synthesis of glucuronides and ascorbate has been reported to be dependent on the extent of the glycogen stores and on the rate of glycogenolysis in the liver. It is common that the final steps of these pathways are catalysed by intraluminally orientated enzymes of the endoplasmic reticulum, which are supported by transporters for the permeation of substrates and products. On the basis of the close morphological and functional proximity of glycogen, glycogen-dependent pathways and the (smooth) endoplasmic reticulum we propose to use the term glycogenoreticular system for the description of this export-orientated hepatocyte-specific metabolic unit.
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Affiliation(s)
- G Bánhegyi
- Semmelweis University, Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Budapest, H1444, Hungary
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21
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El-Ridi MR, Rahmy TR. ACTION OF VITAMIN C AGAINST ACETAMINOPHEN-INDUCED HEPATORENAL TOXICITY IN RATS. ACTA ACUST UNITED AC 2000. [DOI: 10.1081/txr-100102324] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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22
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Csala M, Bánhegyi G, Braun L, Szirmai R, Burchell A, Burchell B, Benedetti A, Mandl J. Beta-glucuronidase latency in isolated murine hepatocytes. Biochem Pharmacol 2000; 59:801-5. [PMID: 10718338 DOI: 10.1016/s0006-2952(99)00392-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The physiological function of microsomal beta-glucuronidase is unclear. Substrates may be either glucuronides produced in the lumen of endoplasmic reticulum (ER) or those taken up by hepatocytes. In the latter case, efficient inward transport of glucuronides at the plasma membrane and the ER membrane would be required. Therefore, the potential role of beta-glucuronidase in ER was investigated. Isolated mouse hepatocytes and mouse and rat liver microsomal vesicles were used in the experiments. Selective permeabilization of the plasma membrane of isolated hepatocytes with saponin or digitonin resulted in an almost 4-fold elevation in the rate of beta-nitrophenol glucuronide hydrolysis, while the permeabilization of plasma membrane plus ER membrane by Triton X-100 caused a further 2-fold elevation. In microsomal vesicles, the p-nitrophenol glucuronide or phenolphthalein glucuronide beta-glucuronidase activity showed about 50% latency as revealed by alamethicin or Triton X-100 treatment. A light-scattering study indicated that the microsomes are relatively impermeable to both glucuronides and to glucuronate. On the basis of our results, the role of liver microsomal beta-glucuronidase in the deconjugation of glucuronides taken up by the liver seems unlikely. Hydrolysis of the glucuronides produced in the ER lumen may play a role in substrate supply for ascorbate synthesis or in "proofreading" of glucuronidation.
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Affiliation(s)
- M Csala
- Department of Medical Chemistry, Semmelweis University of Medicine, Budapest, Hungary
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23
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Neyrinck A, Eeckhoudt SL, Meunier CJ, Pampfer S, Taper HS, Verbeeck RK, Delzenne N. Modulation of paracetamol metabolism by Kupffer cells: a study on rat liver slices. Life Sci 2000; 65:2851-9. [PMID: 10622274 DOI: 10.1016/s0024-3205(99)00554-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Recent studies support the hypothesis that non parenchymal cells (mainly macrophages) may play a role in the metabolism and cellular effects of paracetamol. In order to investigate this hypothesis, male Wistar rats were intravenously injected with either 7.5 mg/kg gadolinium chloride (Gd+) or NaCl 0.9% (Gd-). The treatment with GdCl3 decreased the number and the function of Kupffer cells in liver tissue, as assessed by the histological examination of the liver after colloidal carbon injection in the portal vein. Precision-cut liver slices (PCLS) were prepared from both groups of rats and cultured for 8h in Waymouth's medium in the presence and absence of 5 mM paracetamol. Interestingly, PCLS obtained from Gd+ rats exhibited a lower release of tumor necrosis factor (TNF-alpha) and a better viability than PCLS from control (Gd-) rats. Incubation with paracetamol led to a decreased glycogen level in liver slices from Gd+ or Gd-, without modifying neither liver morphology nor ATP level nor LDH release. A higher proportion of paracetamol glucuronide, was secreted from the slices obtained from Gd+ rats. These data suggest that Kupffer cells could affect the viability of PCLS in culture and are involved in the regulation of phase II metabolism in the adjacent hepatocytes. We propose that PCLS in culture is a suitable model to elucidate the biochemical mechanism underlying the modulation of metabolism occurring through hepatocytes-Kupffer cells interactions.
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Affiliation(s)
- A Neyrinck
- Université Catholique de Louvain, Unité de Pharmacocinétique, Métabolisme, Nutrition et Toxicologie, UCL-PMNT 7369, Brussels, Belgium
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Lykkesfeldt J, Hagen TM, Vinarsky V, Ames BN. Age-associated decline in ascorbic acid concentration, recycling, and biosynthesis in rat hepatocytes--reversal with (R)-alpha-lipoic acid supplementation. FASEB J 1998; 12:1183-9. [PMID: 9737721 DOI: 10.1096/fasebj.12.12.1183] [Citation(s) in RCA: 111] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Ascorbic acid recycling from dehydroascorbic acid and biosynthesis from gulono-1,4-lactone were used as measures of cellular response capacity to increased oxidative stress induced by tert-butylhydroperoxide. The hepatic ascorbic acid concentration was 54% lower in cells from old rats when compared to cells isolated from young rats (P<0.0005). Freshly isolated hepatocytes from old rats exhibited a significantly decreased ascorbic acid recycling capacity in response to oxidative stress (P<0.005) compared to cells from young rats. Ascorbic acid synthesis in these cells from old animals was unaffected by various concentrations of tert-butylhydroperoxide, but amounted to only approximately half of the biosynthetic rate when compared to cells from young animals (P<0.001). Cells from young animals were not significantly affected by the tert-butylhydroperoxide treatments. The results demonstrate a declining ability with age to respond to increased oxidative stress. (R)-alpha-Lipoic acid, a mitochondrial coenzyme, is a powerful antioxidant. A two-week dietary supplementation of old animals with 0.5% (R)-alpha-lipoic acid prior to cell isolation almost completely reversed the age-associated effects on ascorbic acid concentration (P<0.0001), recycling (P<0.05) and biosynthesis after oxidative stress. These results provide further evidence for the potential of alpha-lipoic acid in treatment of diseases related to oxidative stress. Furthermore, the study extends the value of ascorbic acid as a biomarker of oxidative stress.
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Affiliation(s)
- J Lykkesfeldt
- Department of Molecular and Cell Biology, University of California at Berkeley, 94720, USA.
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25
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BANHEGYI GABOR, BRAUN LASZLO, CSALA MIKLOS, PUSKAS FERENC, SOMOGYI ANIKO, KARDON TAMAS, MANDL JOZSEF. Ascorbate and Environmental Stressa. Ann N Y Acad Sci 1998. [DOI: 10.1111/j.1749-6632.1998.tb09004.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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26
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Braun L, Kardon T, Puskás F, Csala M, Bánhegyi G, Mandl J. Regulation of glucuronidation by glutathione redox state through the alteration of UDP-glucose supply originating from glycogen metabolism. Arch Biochem Biophys 1997; 348:169-73. [PMID: 9390188 DOI: 10.1006/abbi.1997.0379] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The effect of altered redox state of glutathione was investigated on p-nitrophenol glucuronidation in isolated mouse hepatocytes. Decrease of GSH/GSSG ratio provoked by various agents caused increased glucuronidation which was accompanied by stimulated glycogenolysis and elevated UDP-glucose content. The stimulation of glycogenolysis and glucuronidation by glutathione consumption could be prevented by the reduction of oxidized glutathione with dithiothreitol and by the glycogenolysis inhibitor fructose. In permeabilized hepatocytes glycogen metabolism, bypassed by the addition of UDP-glucose, stimulated glucuronidation which was insensitive to glutathione depletion. In liver microsomes either UDP-glucuronosyltransferase activity or UDP-glucuronic acid transport was not influenced by GSH/GSSG ratio. These results suggest that alteration of the GSH/GSSG ratio regulates glucuronidation by affecting enzymes of the glycogen metabolism via the modification of UDP-glucuronate supply.
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Affiliation(s)
- L Braun
- Department of Medical Chemistry, Semmelweis University of Medicine, Budapest, Hungary
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27
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Abstract
This article provides a comprehensive review on ascorbate metabolism in animal cells, especially in hepatocytes. The authors deal with the synthesis and the breakdown of ascorbate as a part of the antioxidant and carbohydrate metabolism. Hepatocellular and interorgan cycles with the participation of ascorbate are proposed, based on experiments with murine and human cells; reactions of hexuronic acid pathway, non-oxidative branch of the pentose phosphate cycle, glycolysis and gluconeogenesis are involved. Besides the well-known redox coupling between the two major water-soluble antioxidants (glutathione and ascorbate), their metabolic links have been also outlined. Glycogenolysis as a major source of UDP-glucuronic acid determines the rate of hexuronic acid pathway leading to ascorbate synthesis. Glycogenolysis is regulated by oxidized and reduced glutathione; therefore, glycogen, ascorbate and glutathione metabolism are related to each other. Hydrogen peroxide formation, due to the activity of gulonolactone oxidase catalyzing the last step of ascorbate synthesis, also affects the antioxidant status in hepatocytes. Based on new observations a complex metabolic regulation is supposed. Its element might be present also in humans who lost gulonolactone oxidase but they need and metabolize ascorbate. Finally, the obvious disadvantages and the possible advantages of the lost ascorbate synthesizing ability in humans are considered.
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Affiliation(s)
- G Bánhegyi
- Department of Medical Chemistry, Semmelweis University of Medicine, Budapest, Hungary.
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