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Kalamkar S, Acharya J, Kolappurath Madathil A, Gajjar V, Divate U, Karandikar-Iyer S, Goel P, Ghaskadbi S. Randomized Clinical Trial of How Long-Term Glutathione Supplementation Offers Protection from Oxidative Damage and Improves HbA1c in Elderly Type 2 Diabetic Patients. Antioxidants (Basel) 2022; 11:antiox11051026. [PMID: 35624890 PMCID: PMC9137531 DOI: 10.3390/antiox11051026] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 05/20/2022] [Indexed: 02/06/2023] Open
Abstract
Complications in type 2 diabetes (T2D) arise from hyperglycemia-induced oxidative stress. Here, we examined the effectiveness of supplementation with the endogenous antioxidant glutathione (GSH) during anti-diabetic treatment. A total of 104 non-diabetic and 250 diabetic individuals on anti-diabetic therapy, of either sex and aged between 30 and 78 years, were recruited. A total of 125 diabetic patients were additionally given 500 mg oral GSH supplementation daily for a period of six months. Fasting and PP glucose, insulin, HbA1c, GSH, oxidized glutathione (GSSG), and 8-hydroxy-2-deoxy guanosine (8-OHdG) were measured upon recruitment and after three and six months of supplementation. Statistical significance and effect size were assessed longitudinally across all arms. Blood GSH increased (Cohen’s d = 1.01) and 8-OHdG decreased (Cohen’s d = −1.07) significantly within three months (p < 0.001) in diabetic individuals. A post hoc sub-group analysis showed that HbA1c (Cohen’s d = −0.41; p < 0.05) and fasting insulin levels (Cohen’s d = 0.56; p < 0.05) changed significantly in diabetic individuals above 55 years. GSH supplementation caused a significant increase in blood GSH and helped maintain the baseline HbA1c overall. These results suggest GSH supplementation is of considerable benefit to patients above 55 years, not only supporting decreased glycated hemoglobin (HbA1c) and 8-OHdG but also increasing fasting insulin. The clinical implication of our study is that the oral administration of GSH potentially complements anti-diabetic therapy in achieving better glycemic targets, especially in the elderly population.
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Affiliation(s)
- Saurabh Kalamkar
- Department of Zoology, Savitribai Phule Pune University, Pune 411007, India; (S.K.); (J.A.)
| | - Jhankar Acharya
- Department of Zoology, Savitribai Phule Pune University, Pune 411007, India; (S.K.); (J.A.)
| | | | - Vijay Gajjar
- Department of Medicine, Jehangir Hospital, Pune 411001, India;
| | - Uma Divate
- Jehangir Clinical Development Centre, Pune 411001, India;
| | | | - Pranay Goel
- Biology Division, Indian Institute of Science Education and Research, Pune 411008, India;
- Correspondence: (P.G.); (S.G.); Tel.: +91-202-569-0617 (S.G.)
| | - Saroj Ghaskadbi
- Department of Zoology, Savitribai Phule Pune University, Pune 411007, India; (S.K.); (J.A.)
- Correspondence: (P.G.); (S.G.); Tel.: +91-202-569-0617 (S.G.)
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Carter CS, Huang SC, Searby CC, Cassaidy B, Miller MJ, Grzesik WJ, Piorczynski TB, Pak TK, Walsh SA, Acevedo M, Zhang Q, Mapuskar KA, Milne GL, Hinton AO, Guo DF, Weiss R, Bradberry K, Taylor EB, Rauckhorst AJ, Dick DW, Akurathi V, Falls-Hubert KC, Wagner BA, Carter WA, Wang K, Norris AW, Rahmouni K, Buettner GR, Hansen JM, Spitz DR, Abel ED, Sheffield VC. Counterpoint: An alternative hypothesis for why exposure to static magnetic and electric fields treats type 2 diabetes. Am J Physiol Endocrinol Metab 2021; 320:E1001-E1002. [PMID: 33843282 PMCID: PMC8238130 DOI: 10.1152/ajpendo.00110.2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 03/24/2021] [Indexed: 12/14/2022]
Affiliation(s)
- Calvin S Carter
- Division of Medical Genetics and Genomics, Department of Pediatrics, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - Sunny C Huang
- Division of Medical Genetics and Genomics, Department of Pediatrics, University of Iowa Hospitals & Clinics, Iowa City, Iowa
- Medical Scientist Training Program, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Charles C Searby
- Division of Medical Genetics and Genomics, Department of Pediatrics, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - Benjamin Cassaidy
- Division of Medical Genetics and Genomics, Department of Pediatrics, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - Michael J Miller
- Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa
| | - Wojciech J Grzesik
- Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Ted B Piorczynski
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, Utah
| | - Thomas K Pak
- Division of Medical Genetics and Genomics, Department of Pediatrics, University of Iowa Hospitals & Clinics, Iowa City, Iowa
- Medical Scientist Training Program, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Susan A Walsh
- Division of Nuclear Medicine, Department of Radiology, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - Michael Acevedo
- Division of Nuclear Medicine, Department of Radiology, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - Qihong Zhang
- Division of Medical Genetics and Genomics, Department of Pediatrics, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - Kranti A Mapuskar
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - Ginger L Milne
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Antentor O Hinton
- Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Deng-Fu Guo
- Department of Neuroscience and Pharmacology, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - Robert Weiss
- Division of Cardiology, Department of Internal Medicine, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - Kyle Bradberry
- Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Eric B Taylor
- Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
- Department of Molecular Physiology and Biophysics, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - Adam J Rauckhorst
- Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
- Department of Molecular Physiology and Biophysics, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - David W Dick
- Division of Nuclear Medicine, Department of Radiology, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - Vamsidhar Akurathi
- Division of Nuclear Medicine, Department of Radiology, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - Kelly C Falls-Hubert
- Medical Scientist Training Program, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - Brett A Wagner
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - Walter A Carter
- Division of Medical Genetics and Genomics, Department of Pediatrics, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - Kai Wang
- Division of Medical Genetics and Genomics, Department of Pediatrics, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - Andrew W Norris
- Division of Medical Genetics and Genomics, Department of Pediatrics, University of Iowa Hospitals & Clinics, Iowa City, Iowa
- Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Kamal Rahmouni
- Department of Neuroscience and Pharmacology, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - Garry R Buettner
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - Jason M Hansen
- Division of Nuclear Medicine, Department of Radiology, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - Douglas R Spitz
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - E Dale Abel
- Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
- Division of Endocrinology and Metabolism, Department of Internal Medicine, University of Iowa Hospitals & Clinics, Iowa City, Iowa
| | - Val C Sheffield
- Division of Medical Genetics and Genomics, Department of Pediatrics, University of Iowa Hospitals & Clinics, Iowa City, Iowa
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Søndergård SD, Cintin I, Kuhlman AB, Morville TH, Bergmann ML, Kjær LK, Poulsen HE, Giustarini D, Rossi R, Dela F, Helge JW, Larsen S. The effects of 3 weeks of oral glutathione supplementation on whole body insulin sensitivity in obese males with and without type 2 diabetes: a randomized trial. Appl Physiol Nutr Metab 2021; 46:1133-1142. [PMID: 33740389 DOI: 10.1139/apnm-2020-1099] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The effect of oral glutathione (GSH) supplementation was studied in obese subjects with and without type 2 diabetes (T2DM) on measures of glucose homeostasis and markers of oxidative stress. Twenty subjects (10 patients with T2DM and 10 obese subjects) were recruited for the study, and randomized in a double-blinded placebo-controlled manner to consume either 1000 mg GSH per day or placebo for 3 weeks. Before and after the 3 weeks insulin sensitivity was measured with the hyperinsulinemic-euglycemic clamp and a muscle biopsy was obtained to measure GSH and skeletal muscle mitochondrial hydrogen peroxide (H2O2) emission rate. Whole body insulin sensitivity increased significantly in the GSH group. Skeletal muscle GSH was numerically increased (∼19%) in the GSH group; no change was seen in GSH to glutathione disulfide ratio. Skeletal muscle mitochondrial H2O2 emission rate did not change in response to the intervention and neither did the urinary excretion of the RNA oxidation product 8-oxo-7,8-dihydroguanosine or the DNA oxidation product 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), although 8-oxodG decreased as a main effect of time. Oral GSH supplementation improves insulin sensitivity in obese subjects with and without T2DM, although it does not alter markers of oxidative stress. The study has been registered in clinicaltrials.gov (NCT02948673). Novelty: Reduced glutathione supplementation increases insulin sensitivity in obese subjects with and without T2DM. H2O2 emission rate from skeletal muscle mitochondria was not affected by GSH supplementation.
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Affiliation(s)
- Stine D Søndergård
- Xlab, Center for Healthy Aging, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ida Cintin
- Xlab, Center for Healthy Aging, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Anja B Kuhlman
- Xlab, Center for Healthy Aging, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Thomas H Morville
- Xlab, Center for Healthy Aging, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark.,Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Marie Louise Bergmann
- Xlab, Center for Healthy Aging, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Laura K Kjær
- Laboratory of Clinical Pharmacology, Department of Clinical Pharmacology, Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark
| | - Henrik E Poulsen
- Laboratory of Clinical Pharmacology, Department of Clinical Pharmacology, Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark
| | - Daniela Giustarini
- Department of Biotechnology Chemistry and Pharmacy, University of Siena, Siena, Italy
| | - Ranieri Rossi
- Department of Biotechnology Chemistry and Pharmacy, University of Siena, Siena, Italy
| | - Flemming Dela
- Xlab, Center for Healthy Aging, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark.,Department of Geriatrics, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Jørn W Helge
- Xlab, Center for Healthy Aging, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Steen Larsen
- Xlab, Center for Healthy Aging, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark.,Clinical Research Centre, Medical University of Bialystok, Bialystok, Poland
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Carter CS, Huang SC, Searby CC, Cassaidy B, Miller MJ, Grzesik WJ, Piorczynski TB, Pak TK, Walsh SA, Acevedo M, Zhang Q, Mapuskar KA, Milne GL, Hinton AO, Guo DF, Weiss R, Bradberry K, Taylor EB, Rauckhorst AJ, Dick DW, Akurathi V, Falls-Hubert KC, Wagner BA, Carter WA, Wang K, Norris AW, Rahmouni K, Buettner GR, Hansen JM, Spitz DR, Abel ED, Sheffield VC. Exposure to Static Magnetic and Electric Fields Treats Type 2 Diabetes. Cell Metab 2020; 32:561-574.e7. [PMID: 33027675 PMCID: PMC7819711 DOI: 10.1016/j.cmet.2020.09.012] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 06/29/2020] [Accepted: 09/11/2020] [Indexed: 12/17/2022]
Abstract
Aberrant redox signaling underlies the pathophysiology of many chronic metabolic diseases, including type 2 diabetes (T2D). Methodologies aimed at rebalancing systemic redox homeostasis have had limited success. A noninvasive, sustained approach would enable the long-term control of redox signaling for the treatment of T2D. We report that static magnetic and electric fields (sBE) noninvasively modulate the systemic GSH-to-GSSG redox couple to promote a healthier systemic redox environment that is reducing. Strikingly, when applied to mouse models of T2D, sBE rapidly ameliorates insulin resistance and glucose intolerance in as few as 3 days with no observed adverse effects. Scavenging paramagnetic byproducts of oxygen metabolism with SOD2 in hepatic mitochondria fully abolishes these insulin sensitizing effects, demonstrating that mitochondrial superoxide mediates induction of these therapeutic changes. Our findings introduce a remarkable redox-modulating phenomenon that exploits endogenous electromagneto-receptive mechanisms for the noninvasive treatment of T2D, and potentially other redox-related diseases.
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Affiliation(s)
- Calvin S Carter
- Department of Pediatrics and Division of Medical Genetics and Genomics, University of Iowa Hospitals & Clinics, Iowa City, IA, USA.
| | - Sunny C Huang
- Department of Pediatrics and Division of Medical Genetics and Genomics, University of Iowa Hospitals & Clinics, Iowa City, IA, USA; Medical Scientist Training Program, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Charles C Searby
- Department of Pediatrics and Division of Medical Genetics and Genomics, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Benjamin Cassaidy
- Department of Pediatrics and Division of Medical Genetics and Genomics, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Michael J Miller
- Department of Physics and Astronomy, University of Iowa, Iowa City, IA, USA
| | - Wojciech J Grzesik
- Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Ted B Piorczynski
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT, USA
| | - Thomas K Pak
- Department of Pediatrics and Division of Medical Genetics and Genomics, University of Iowa Hospitals & Clinics, Iowa City, IA, USA; Medical Scientist Training Program, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Susan A Walsh
- Department of Radiology, Division of Nuclear Medicine, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Michael Acevedo
- Department of Radiology, Division of Nuclear Medicine, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Qihong Zhang
- Department of Pediatrics and Division of Medical Genetics and Genomics, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Kranti A Mapuskar
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Ginger L Milne
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Antentor O Hinton
- Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Deng-Fu Guo
- Department of Neuroscience and Pharmacology, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Robert Weiss
- Department of Internal Medicine, Division of Cardiology, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Kyle Bradberry
- Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Eric B Taylor
- Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, USA; Department of Molecular Physiology and Biophysics, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Adam J Rauckhorst
- Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, USA; Department of Molecular Physiology and Biophysics, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - David W Dick
- Department of Radiology, Division of Nuclear Medicine, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Vamsidhar Akurathi
- Department of Radiology, Division of Nuclear Medicine, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Kelly C Falls-Hubert
- Medical Scientist Training Program, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, USA; Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Brett A Wagner
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Walter A Carter
- Department of Pediatrics and Division of Medical Genetics and Genomics, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Kai Wang
- College of Public Health, Department of Biostatistics, University of Iowa, Iowa City, IA, USA
| | - Andrew W Norris
- Department of Pediatrics and Division of Medical Genetics and Genomics, University of Iowa Hospitals & Clinics, Iowa City, IA, USA; Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Kamal Rahmouni
- Department of Neuroscience and Pharmacology, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Garry R Buettner
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Jason M Hansen
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT, USA
| | - Douglas R Spitz
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - E Dale Abel
- Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, USA; Department of Internal Medicine, Division of Endocrinology and Metabolism, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Val C Sheffield
- Department of Pediatrics and Division of Medical Genetics and Genomics, University of Iowa Hospitals & Clinics, Iowa City, IA, USA.
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A Translational In Vivo and In Vitro Metabolomic Study Reveals Altered Metabolic Pathways in Red Blood Cells of Type 2 Diabetes. J Clin Med 2020; 9:jcm9061619. [PMID: 32471219 PMCID: PMC7355709 DOI: 10.3390/jcm9061619] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 05/19/2020] [Accepted: 05/24/2020] [Indexed: 12/21/2022] Open
Abstract
Clinical parameters used in type 2 diabetes mellitus (T2D) diagnosis and monitoring such as glycosylated haemoglobin (HbA1c) are often unable to capture important information related to diabetic control and chronic complications. In order to search for additional biomarkers, we performed a pilot study comparing T2D patients with healthy controls matched by age, gender, and weight. By using 1H-nuclear magnetic resonance (NMR) based metabolomics profiling of red blood cells (RBCs), we found that the metabolic signature of RBCs in T2D subjects differed significantly from non-diabetic controls. Affected metabolites included glutathione, 2,3-bisphophoglycerate, inosinic acid, lactate, 6-phosphogluconate, creatine and adenosine triphosphate (ATP) and several amino acids such as leucine, glycine, alanine, lysine, aspartate, phenylalanine and tyrosine. These results were validated by an independent cohort of T2D and control patients. An analysis of the pathways in which these metabolites were involved showed that energetic and redox metabolism in RBCs were altered in T2D, as well as metabolites transported by RBCs. Taken together, our results revealed that the metabolic profile of RBCs can discriminate healthy controls from T2D patients. Further research is needed to determine whether metabolic fingerprint in RBC could be useful to complement the information obtained from HbA1c and glycemic variability as well as its potential role in the diabetes management.
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Enzymatic glutaredoxin-dependent method to determine glutathione and protein S-glutathionylation using fluorescent eosin-glutathione. Anal Biochem 2019; 568:24-30. [DOI: 10.1016/j.ab.2018.12.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 10/18/2018] [Accepted: 12/27/2018] [Indexed: 11/18/2022]
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Al-Khaldi A, Sultan S. The expression of sirtuins, superoxide dismutase, and lipid peroxidation status in peripheral blood from patients with diabetes and hypothyroidism. BMC Endocr Disord 2019; 19:19. [PMID: 30736780 PMCID: PMC6368800 DOI: 10.1186/s12902-019-0350-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Accepted: 02/04/2019] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Sirtuin 1 (SIRT1) and sirtuin 3 (SIRT3) proteins have an important role in counteracting oxidative stress. Although diabetes and hypothyroidism (HT) are both characterized by oxidative stress, the mechanisms are not fully understood. This study investigated the effects of type 1 diabetes (T1D), type 2 diabetes (T2D), and HT on the expression levels of SIRT1, SIRT3, and manganese superoxide dismutase (SOD2). METHODS Gene expression of SIRT1, SIRT3, and SOD2 was measured using real-time PCR. The protein expression of SOD2 and lipid peroxidation (thiobarbituric acid reactive substances) was measured by the TBARS Assay kit and enzyme-linked immunosorbent assay (ELISA) respectively. RESULTS The results showed that the SIRT1 and SIRT3 levels were lower in peripheral blood samples from patients with T1D, T2D, or HT than in healthy individuals. Interestingly, the mRNA and protein expression levels of SOD2 were higher in all three patient groups. Lipid peroxidation was higher in the patients with HT than in the healthy individuals. CONCLUSIONS These results indicate alterations in the expression levels of sirtuins and superoxide dismutase in diabetes and HT, which may be related, at least in part, to the oxidative stress. Identifying such alterations in those patients will pave the way towards the development of drugs to enhance SIRT1 and SIRT3 expression and their activity to prevent the damaging effect of oxidative stress.
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Affiliation(s)
- Abdullah Al-Khaldi
- Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Samar Sultan
- Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.
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Lavoie S, Steullet P, Kulak A, Preitner F, Do KQ, Magistretti PJ. Glutamate Cysteine Ligase-Modulatory Subunit Knockout Mouse Shows Normal Insulin Sensitivity but Reduced Liver Glycogen Storage. Front Physiol 2016; 7:142. [PMID: 27148080 PMCID: PMC4838631 DOI: 10.3389/fphys.2016.00142] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 04/04/2016] [Indexed: 01/22/2023] Open
Abstract
Glutathione (GSH) deficits have been observed in several mental or degenerative illness, and so has the metabolic syndrome. The impact of a decreased glucose metabolism on the GSH system is well-known, but the effect of decreased GSH levels on the energy metabolism is unclear. The aim of the present study was to investigate the sensitivity to insulin in the mouse knockout (KO) for the modulatory subunit of the glutamate cysteine ligase (GCLM), the rate-limiting enzyme of GSH synthesis. Compared to wildtype (WT) mice, GCLM-KO mice presented with reduced basal plasma glucose and insulin levels. During an insulin tolerance test, GCLM-KO mice showed a normal fall in glycemia, indicating normal insulin secretion. However, during the recovery phase, plasma glucose levels remained lower for longer in KO mice despite normal plasma glucagon levels. This is consistent with a normal counterregulatory hormonal response but impaired mobilization of glucose from endogenous stores. Following a resident-intruder stress, during which stress hormones mobilize glucose from hepatic glycogen stores, KO mice showed a lower hyperglycemic level despite higher plasma cortisol levels when compared to WT mice. The lower hepatic glycogen levels observed in GCLM-KO mice could explain the impaired glycogen mobilization following induced hypoglycemia. Altogether, our results indicate that reduced liver glycogen availability, as observed in GCLM-KO mice, could be at the origin of their lower basal and challenged glycemia. Further studies will be necessary to understand how a GSH deficit, typically observed in GCLM-KO mice, leads to a deficit in liver glycogen storage.
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Affiliation(s)
- Suzie Lavoie
- Department of Psychiatry, Centre for Psychiatric Neuroscience, Lausanne University Hospital and University of LausanneLausanne-Prilly, Switzerland; Orygen, The National Centre of Excellence in Youth Mental Health, Centre for Youth Mental Health, The University of MelbourneParkville, VIC, Australia
| | - Pascal Steullet
- Department of Psychiatry, Centre for Psychiatric Neuroscience, Lausanne University Hospital and University of Lausanne Lausanne-Prilly, Switzerland
| | - Anita Kulak
- Department of Psychiatry, Centre for Psychiatric Neuroscience, Lausanne University Hospital and University of Lausanne Lausanne-Prilly, Switzerland
| | - Frederic Preitner
- Mouse Metabolic Evaluation Facility, Center for Integrative Genomics, University of Lausanne Lausanne, Switzerland
| | - Kim Q Do
- Department of Psychiatry, Centre for Psychiatric Neuroscience, Lausanne University Hospital and University of Lausanne Lausanne-Prilly, Switzerland
| | - Pierre J Magistretti
- Department of Psychiatry, Centre for Psychiatric Neuroscience, Lausanne University Hospital and University of LausanneLausanne-Prilly, Switzerland; Laboratory of Neuroenergetics and Cellular Dynamics, Brain Mind Institute, Ecole Polytechnique Fédérale de LausanneLausanne, Switzerland; BESE Division, King Abdullah University of Sciences and Technology (KAUST)Thuwal, Saudi Arabia
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9
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Oxidative stress and metabolic pathologies: from an adipocentric point of view. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2014; 2014:908539. [PMID: 25143800 PMCID: PMC4131099 DOI: 10.1155/2014/908539] [Citation(s) in RCA: 154] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Revised: 05/20/2014] [Accepted: 06/26/2014] [Indexed: 02/07/2023]
Abstract
Oxidative stress plays a pathological role in the development of various diseases including diabetes, atherosclerosis, or cancer. Systemic oxidative stress results from an imbalance between oxidants derivatives production and antioxidants defenses. Reactive oxygen species (ROS) are generally considered to be detrimental for health. However, evidences have been provided that they can act as second messengers in adaptative responses to stress. Obesity represents a major risk factor for deleterious associated pathologies such as type 2 diabetes, liver, and coronary heart diseases. Many evidences regarding obesity-induced oxidative stress accumulated over the past few years based on established correlations of biomarkers or end-products of free-radical-mediated oxidative stress with body mass index. The hypothesis that oxidative stress plays a significant role in the development of metabolic disorders, especially insulin-resistance state, is supported by several studies where treatments reducing ROS production reverse metabolic alterations, notably through improvement of insulin sensitivity, hyperlipidemia, or hepatic steatosis. In this review, we will develop the mechanistic links between oxidative stress generated by adipose tissue in the context of obesity and its impact on metabolic complications development. We will also attempt to discuss potential therapeutic approaches targeting obesity-associated oxidative stress in order to prevent associated-metabolic complications.
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Kulkarni R, Acharya J, Ghaskadbi S, Goel P. Thresholds of oxidative stress in newly diagnosed diabetic patients on intensive glucose-control therapy. PLoS One 2014; 9:e100897. [PMID: 24971653 PMCID: PMC4074157 DOI: 10.1371/journal.pone.0100897] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Accepted: 06/02/2014] [Indexed: 12/18/2022] Open
Abstract
Cellular and animal studies suggest that oxidative stress could be the central defect underlying both beta-cell dysfunction and insulin resistance in type 2 diabetes mellitus. A reduction of glycemic stress in diabetic patients on therapy alleviates systemic oxidative stress and improves insulin resistance and beta-cell secretion. Monitoring oxidative stress systematically with glucose can potentially identify an individual's recovery trajectory. To determine a quantitative model of serial changes in oxidative stress, as measured via the antioxidant glutathione, we followed patients newly diagnosed with diabetes over 8 weeks of starting anti-diabetic treatment. We developed a mathematical model which shows recovery is marked with a quantal response. For each individual the model predicts three theoretical quantities: an estimate of maximal glutathione at low stress, a glucose threshold for half-maximal glutathione, and a rate at which recovery progresses. Individual patients are seen to vary considerably in their response to glucose control. Thus, model estimates can potentially be used to determine whether an individual patient's response is better or worse than average in terms of each of these indices; they can therefore be useful in reassessing treatment strategy. We hypothesize that this method can aid the personalization of effective targets of glucose control in anti-diabetic therapy.
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Affiliation(s)
- Rashmi Kulkarni
- Department of Biology, Indian Institute of Science Education and Research, Pune, Maharashtra, India
| | - Jhankar Acharya
- Department of Zoology, University of Pune, Pune, Maharashtra, India
| | - Saroj Ghaskadbi
- Department of Zoology, University of Pune, Pune, Maharashtra, India
| | - Pranay Goel
- Mathematics and Biology, Indian Institute of Science Education and Research, Pune, Maharashtra, India
- * E-mail:
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Saravanan G, Ponmurugan P. S-allylcysteine Improves Streptozotocin-Induced Alterations of Blood Glucose, Liver Cytochrome P450 2E1, Plasma Antioxidant System, and Adipocytes Hormones in Diabetic Rats. Int J Endocrinol Metab 2013; 11:e10927. [PMID: 24719626 PMCID: PMC3968993 DOI: 10.5812/ijem.10927] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2013] [Revised: 03/09/2013] [Accepted: 03/17/2013] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND S-allylcysteine, a garlic derivative, could have a protective effect against pathogenesis of diabetes mellitus. OBJECTIVES Sustained free radical generation and oxidative damage to system leads to the final conclusion phase of diabetes and also it coexists with a constant diminution in the antioxidant status.The present study aims to evaluate the therapeutic effects of S-allylcysteine (SAC) against adipocytes hormones and antioxidant defense systems of plasma and erythrocytes of treptozotocin (STZ) induced diabetes in rats. MATERIALS AND METHODS Diabetic rats were administered SAC (150 mg/kg b.w) orally for 45 days. At 46(th) day, the rats were anesthetized, and blood and liver sample were collected for analyzing glucose, plasma insulin, CYP2E1 activity, Thiobarbituric acid reactive substances (TBARS), hydroperoxide, enzymatic and nonenzymatic antioxidants, reduced glutathione (GSH), ceruloplasmin, plasma leptin, and adiponectin. RESULTS The levels of glucose, CYP2E1 activity, Thiobarbituric acid reactive substances (TBARS), hydroperoxide, and ceruloplasmin were increased significantly; whereas, the levels of plasma insulin, reduced glutathione, enzymatic and nonenzymatic antioxidants, leptin and adiponectin were decreased in experimental diabetic rats. Administration of SAC to diabetic rats led to a decrease in the levels of glucose, CYP2E1 activity, TBARS, and ceruloplasmin. In addition, the levels of plasma insulin, enzymatic and nonenzymatic antioxidants leptin and adiponectin were increased in SAC treated diabetic rats. Gliclazide, a standard drug for diabetes, was used for the comparative purpose. CONCLUSIONS The results of the present investigation suggest that SAC could be used as a food supplement in the treatment of diabetes characterized by provoked antioxidant status, altered blood glucose, and hormones level.
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Affiliation(s)
- Ganapathy Saravanan
- Department of Biochemistry, Centre for Biological science, K.S.Rangasamy College of Arts and Science, Thokkavadi, Tiruchengode,Tamil Nadu, India
- Corresponding author: Ganapathy Saravanan, Research Department of Biochemistry, Centre for Biological Science, K. S. Rangasamy College of Arts and Science, Thokkavadi, Tiruchengode, Tamil Nadu, 637215, India. Tel: +91-9843954422, E-mail:
| | - Ponnusamy Ponmurugan
- Department of Biotechnology, K.S.Rangasamy College of Technology, Thokkavadi, Tiruchengode, Tamil Nadu, India
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Yur F, Dede S, Karaca T, Çiftçi Yegin S, Değer Y, Özdemir H. The Effect of Glutathione Treatment on the Biochemical and Immunohistochemical Profile in Streptozotocin-Induced Diabetic Rats. J Membr Biol 2013; 246:427-33. [DOI: 10.1007/s00232-013-9541-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2012] [Accepted: 03/22/2013] [Indexed: 12/24/2022]
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Fisher G, Alvarez JA, Ellis AC, Granger WM, Ovalle F, Man CD, Cobelli C, Gower BA. Race differences in the association of oxidative stress with insulin sensitivity in African- and European-American women. Obesity (Silver Spring) 2012; 20:972-7. [PMID: 22173574 PMCID: PMC3687548 DOI: 10.1038/oby.2011.355] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Excessive metabolism of glucose and/or fatty acids may impair insulin signaling by increasing oxidative stress. The objective of this study was to examine the association between insulin sensitivity and protein carbonyls, a systemic marker of oxidative stress, in healthy, nondiabetic women, and to determine if the relationship differed with race. Subjects were 25 African-Americans (AA, BMI 28.4 ± 6.2 kg/m(2), range 18.8-42.6 kg/m(2); age 33.1 ± 13.5 years, range 18-58 years) and 28 European-Americans (EA, BMI 26.2 ± 5.9 kg/m(2), range 18.7-48.4 kg/m(2); age 31.6 ± 12.4 years, range 19-58 years). Insulin sensitivity was determined using an intravenous glucose tolerance test incorporating [6,6-(2)H(2)]-glucose, and a two-compartment mathematical model. Multiple linear regression results indicated that insulin sensitivity was inversely associated with protein carbonyls in AA (standardized regression coefficient -0.47, P < 0.05) but not EA (0.01, P = 0.945), after adjusting for %body fat. In contrast, %body fat was significantly and positively associated with insulin sensitivity in EA (-0.54, P < 0.01) but not AA (-0.24, P = 0.196). Protein carbonyls were associated with free fatty acids (FFA) in AA (r = 0.58, P < 0.01) but not EA (r = -0.11, P = 0.59). When subjects were divided based on median levels of fasting glucose and FFA, those with higher glucose/FFA concentrations had a significantly greater concentration of circulating protein carbonyls compared to those with lower glucose/FFA concentrations (P < 0.05). These results suggest that oxidative stress independently contributes to insulin sensitivity among AA women. Further, this association in AA may be mediated by circulating FFA and/or glucose.
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Affiliation(s)
- Gordon Fisher
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, Alabama, USA.
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14
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Fan X, Zhang J, Theves M, Strauch C, Nemet I, Liu X, Qian J, Giblin FJ, Monnier VM. Mechanism of lysine oxidation in human lens crystallins during aging and in diabetes. J Biol Chem 2009; 284:34618-27. [PMID: 19854833 DOI: 10.1074/jbc.m109.032094] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Oxidative mechanisms during nuclear sclerosis of the lens are poorly understood, in particular metal-catalyzed oxidation. The lysyl oxidation product adipic semialdehyde (allysine, ALL) and its oxidized end-product 2-aminoadipic acid (2-AAA) were determined as a function of age and presence of diabetes. Surprisingly, whereas both ALL and 2-AAA increased with age and strongly correlated with cataract grade and protein absorbance at 350 nm, only ALL formation but not 2-AAA was increased by diabetes. To clarify the mechanism of oxidation, rabbit lenses were treated with hyperbaric oxygen (HBO) for 48 h, and proteins were analyzed by gas and liquid chromatography mass spectrometry for ALL, 2-AAA, and multiple glycation products. Upon exposure to HBO, rabbit lenses were swollen, and nuclei were yellow. Protein-bound ALL increased 8-fold in the nuclear protein fractions versus controls. A dramatic increase in methyl-glyoxal hydroimidazolone and carboxyethyl-lysine but no increase of 2-AAA occurred, suggesting more drastic conditions are needed to oxidize ALL into 2-AAA. Indeed the latter formed only upon depletion of glutathione and was catalyzed by H(2)O(2). Neither carboxymethyl-lysine nor glyoxal hydroimidazolone, two markers of glyco-/lipoxidation, nor markers of lenticular glycemia (fructose-lysine, glucospane) were elevated by HBO, excluding significant lipid peroxidation and glucose involvement. The findings strongly implicate dicarbonyl/metal catalyzed oxidation of lysine to allysine, whereby low GSH combined with ascorbate-derived H(2)O(2) likely contributes toward 2-AAA formation, since virtually no 2-AAA formed in the presence of methylglyoxal instead of ascorbate. An important translational conclusion is that chelating agents might help delay nuclear sclerosis.
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Affiliation(s)
- Xingjun Fan
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio 44106 , USA
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Abdul-Ghani MA, Jani R, Chavez A, Molina-Carrion M, Tripathy D, Defronzo RA. Mitochondrial reactive oxygen species generation in obese non-diabetic and type 2 diabetic participants. Diabetologia 2009; 52:574-82. [PMID: 19183935 DOI: 10.1007/s00125-009-1264-4] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2008] [Accepted: 12/17/2008] [Indexed: 12/21/2022]
Abstract
AIMS/HYPOTHESIS The aim of this study was to measure mitochondrial reactive oxygen species (ROS) production directly from skeletal muscle biopsies obtained from obese insulin-resistant non-diabetic and type 2 diabetic participants. METHODS Ten lean healthy, ten obese non-diabetic and ten type 2 diabetic participants received a euglycaemic-hyperinsulinaemic clamp to measure whole body insulin sensitivity. Mitochondria were isolated from skeletal muscle biopsies, and mitochondrial ATP synthesis and hydrogen peroxide production were measured ex vivo under conditions that maximally stimulate ATP synthesis and ROS production using chemiluminescent and fluorescent techniques, respectively. RESULTS Compared with lean controls, both obese non-diabetic and type 2 diabetic participants were resistant to insulin, and had a reduced rate of mitochondrial ATP production. Obese insulin-resistant participants had a decreased rate of mitochondrial ROS production, while ROS production rate in participants with type 2 diabetes was similar to that in lean healthy participants. In non-diabetic participants, the rate of ROS production was strongly correlated with the rate of ATP synthesis and the glucose disposal rate measured with the euglycaemic-hyperinsulinaemic clamp. The ROS/ATP ratio in obese insulin-resistant participants was similar to that in lean insulin-sensitive participants, while the ratio was significantly elevated in type 2 diabetes participants. CONCLUSIONS/INTERPRETATION Since, in absolute terms, the maximal capacity for mitochondrial ROS production was not increased in either obese insulin-resistant participants or in type 2 diabetic participants, these results do not favour a role for increased mitochondrial ROS production in the pathogenesis of insulin resistance in human skeletal muscle. However, care should be taken in extrapolating these ex vivo observations to the in vivo situation.
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Affiliation(s)
- M A Abdul-Ghani
- Diabetes Division, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive MS 7886, San Antonio, TX 78229, USA.
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Guarino MP, Macedo MP. Co-administration of glutathione and nitric oxide enhances insulin sensitivity in Wistar rats. Br J Pharmacol 2007; 147:959-65. [PMID: 16491098 PMCID: PMC1760719 DOI: 10.1038/sj.bjp.0706691] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The liver modulates insulin sensitivity through a prandial-dependent mechanism that requires activation of the hepatic parasympathetic nerves, hepatic nitric oxide (NO) and hepatic glutathione (GSH). We tested the hypothesis that co-administration of GSH and NO to the liver enhances insulin sensitivity in a GSH and NO dose-dependent manner. 24 h fasted Wistar rats were used. Hepatic GSH was supplemented by administration of glutathione monoethylester (GSH-E; 0.1/0.25/0.5/1/2 mmol kg(-1)) and 3-morpholinosidnonimine (SIN-1; 5/10 mg kg(-1)) was used as a NO donor. The drugs were administered either systemically (i.v.) or intraportally (i.p.v.). Insulin sensitivity was assessed using a transient euglycemic clamp. Neither GSH-E nor SIN-1 increased insulin sensitivity when administered alone, both i.v. and i.p.v. Moreover, changes in insulin sensitivity were not observed when GSH-E was administered i.v. followed by either i.v. or i.p.v. SIN-1 at any of the doses tested. However, i.p.v. administration of GSH-E followed by i.p.v. SIN-1 10 mg kg(-1) significantly increased insulin sensitivity in a GSH-E dose-dependent manner: 26.1+/-9.4% after 0.1 mmol kg(-1) GSH-E; 44.6+/-7.9% after 0.25 mmol kg(-1) GSH-E; 59.4+/-15.1% after 0.5 mmol kg(-1) GSH-E; 138.9+/-12.7% after 1 mmol kg(-1) GSH-E and 117.3+/-29.2% after a dose of 2 mmol kg(-1) (n = 23, P<0.005). Our results confirm that insulin sensitivity is enhanced in a dose-dependent manner by co-administration of NO and GSH donors to the liver.
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Affiliation(s)
- Maria P Guarino
- Department of Pathophysiology, Faculty of Medical Sciences, New University of Lisbon, Campo Mártires da Pátria 130, 1169-056 Lisbon, Portugal
- Department of Physiology, Faculty of Medical Sciences, New University of Lisbon, Campo Mártires da Pátria 130, 1169-056 Lisbon, Portugal
| | - M Paula Macedo
- Department of Physiology, Faculty of Medical Sciences, New University of Lisbon, Campo Mártires da Pátria 130, 1169-056 Lisbon, Portugal
- Portuguese Diabetes Association, Rua do Salitre, 118, 1250-203 Lisbon, Portugal
- Author for correspondence:
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Darmaun D, Smith SD, Sweeten S, Sager BK, Welch S, Mauras N. Evidence for accelerated rates of glutathione utilization and glutathione depletion in adolescents with poorly controlled type 1 diabetes. Diabetes 2005; 54:190-6. [PMID: 15616028 DOI: 10.2337/diabetes.54.1.190] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Depletion of glutathione, an important antioxidant present in red cells, has been reported in type 1 diabetes, but the mechanism of this depletion has not been fully characterized. Glutathione depletion can occur through decreased synthesis, increased utilization, or a combination of both. To address this issue, 5-h infusions of l-[3,3-(2)H(2)]cysteine were performed in 16 diabetic adolescents divided into a well-controlled and a poorly controlled group and in eight healthy nondiabetic teenagers as control subjects (HbA(1c) 6.3 +/- 0.2, 10.5 +/- 0.6, and 4.8 +/- 0.1%, respectively). Glutathione fractional synthesis rate was determined from (2)H(2)-cysteine incorporation into blood glutathione. We observed that 1) erythrocyte cysteine concentration was 41% lower in poorly controlled patients compared with well-controlled patients (P = 0.009); 2) erythrocyte glutathione concentration was approximately 29% and approximately 36% lower in well-controlled and poorly controlled patients compared with healthy volunteers; and 3) the fractional synthesis rate of glutathione, although similar in well-controlled and healthy subjects (83 +/- 14 vs. 82 +/- 11% per day), was substantially higher in the poorly controlled group (141 +/- 23% per day, P = 0.038). These findings suggest that in diabetic adolescents, poor control is associated with a significant depletion of blood glutathione and cysteine, due to increased rates of glutathione utilization. This weakened antioxidant defense may play a role in the pathogenesis of diabetes complications.
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Affiliation(s)
- Dominique Darmaun
- Nemours Children's Clinic, Research Department, 5 North, 807 Children's Way, Jacksonville, FL 32207, USA.
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Nyström T, Nygren A, Sjöholm A. Tetrahydrobiopterin increases insulin sensitivity in patients with type 2 diabetes and coronary heart disease. Am J Physiol Endocrinol Metab 2004; 287:E919-25. [PMID: 15265759 DOI: 10.1152/ajpendo.00046.2004] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Tetrahydrobiopterin (BH(4)) is an essential cofactor of nitric oxide synthase that improves endothelial function in diabetics, smokers, and patients with hypercholesterolemia. Insulin resistance has been suggested as a contributing factor in the development of endothelial dysfunction via an abnormal pteridine metabolism. We hypothesized that BH(4) would restore flow-mediated vasodilation (FMD, endothelial-dependent vasodilation), which may affect insulin resistance in type 2 diabetic patients. Thirty-two subjects (12 type 2 diabetic subjects, 10 matched nondiabetic subjects, and 10 healthy unmatched subjects) underwent infusion of BH(4) or saline in a random crossover study. Insulin sensitivity index (S(I)) was measured by hyperinsulinemic isoglycemic clamp. FMD was measured using ultrasonography. BH(4) significantly increased S(I) in the type 2 diabetics [3.6 +/- 0.6 vs. 4.9 +/- 0.7 x 10(-4) dl.kg(-1).min(-1)/(microU/ml), P < 0.05], while having no effects in nondiabetics [8.9 +/- 1.1 vs. 9.0 +/- 0.9 x 10(-4) dl.kg(-1).min(-1)/(microU/ml), P = 0.92] or in healthy subjects [17.5 +/- 1.6 vs. 18 +/- 1.8 x 10(-4) dl.kg(-1).min(-1)/(microU/ml), P = 0.87]. BH(4) did not affect the relative changes in brachial artery diameter from baseline FMD (%) in type 2 diabetic subjects (2.3 +/- 0.8 vs. 1.8 +/- 1.0%, P = 0.42), nondiabetic subjects (5.3 +/- 1.1 vs. 6.6 +/- 0.9%, P = 0.32), or healthy subjects (11.9 +/- 0.6 vs. 11.0 +/- 1.0%, P = 0.48). In conclusion, BH(4) significantly increases insulin sensitivity in type 2 diabetic patients without any discernible improvement in endothelial function.
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Affiliation(s)
- Thomas Nyström
- Dept. of Internal Medicine, Karolinska Institute, Stockholm South Hospital, Södersjukhuset, Stockholm SE-118 83, Sweden.
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Haber CA, Lam TKT, Yu Z, Gupta N, Goh T, Bogdanovic E, Giacca A, Fantus IG. N-acetylcysteine and taurine prevent hyperglycemia-induced insulin resistance in vivo: possible role of oxidative stress. Am J Physiol Endocrinol Metab 2003; 285:E744-53. [PMID: 12799318 DOI: 10.1152/ajpendo.00355.2002] [Citation(s) in RCA: 168] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Exposure to high concentrations of glucose and insulin results in insulin resistance of metabolic target tissues, a characteristic feature of type 2 diabetes. High glucose has also been associated with oxidative stress, and increased levels of reactive oxygen species have been proposed to cause insulin resistance. To determine whether oxidative stress contributes to insulin resistance induced by hyperglycemia in vivo, nondiabetic rats were infused with glucose for 6 h to maintain a circulating glucose concentration of 15 mM with and without coinfusion of the antioxidant N-acetylcysteine (NAC), followed by a 2-h hyperinsulinemic-euglycemic clamp. High glucose (HG) induced a significant decrease in insulin-stimulated glucose uptake [tracer-determined disappearance rate (Rd), control 41.2 +/- 1.7 vs. HG 32.4 +/- 1.9 mg. kg-1. min-1, P < 0.05], which was prevented by NAC (HG + NAC 45.9 +/- 3.5 mg. kg-1. min-1). Similar results were obtained with the antioxidant taurine. Neither NAC nor taurine alone altered Rd. HG caused a significant (5-fold) increase in soleus muscle protein carbonyl content, a marker of oxidative stress that was blocked by NAC, as well as elevated levels of malondialdehyde and 4-hydroxynonenal, markers of lipid peroxidation, which were reduced by taurine. In contrast to findings after long-term hyperglycemia, there was no membrane translocation of novel isoforms of protein kinase C in skeletal muscle after 6 h. These data support the concept that oxidative stress contributes to the pathogenesis of hyperglycemia-induced insulin resistance.
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Affiliation(s)
- C Andrew Haber
- Department of Medicine, Mount Sinai Hospital, 60 Murray Street, Toronto, Ontario, Canada M5G 1X5
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Guarino MP, Afonso RA, Raimundo N, Raposo JF, Macedo MP. Hepatic glutathione and nitric oxide are critical for hepatic insulin-sensitizing substance action. Am J Physiol Gastrointest Liver Physiol 2003; 284:G588-94. [PMID: 12466146 DOI: 10.1152/ajpgi.00423.2002] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We tested the hypothesis that hepatic nitric oxide (NO) and glutathione (GSH) are involved in the synthesis of a putative hormone referred to as hepatic insulin-sensitizing substance HISS. Insulin action was assessed in Wistar rats using the rapid insulin sensitivity test (RIST). Blockade of hepatic NO synthesis with N(G)-nitro-l-arginine methyl ester (l-NAME, 1.0 mg/kg intraportal) decreased insulin sensitivity by 45.1 +/- 2.1% compared with control (from 287.3 +/- 18.1 to 155.3 +/- 10.1 mg glucose/kg, P < 0.05). Insulin sensitivity was restored to 321.7 +/- 44.7 mg glucose/kg after administration of an NO donor, intraportal SIN-1 (5 mg/kg), which promotes GSH nitrosation, but not after intraportal sodium nitroprusside (20 nmol x kg(-1) x min(-1)), which does not nitrosate GSH. We depleted hepatic GSH using the GSH synthesis inhibitor l-buthionine-[S,R]-sulfoximine (BSO, 2 mmol/kg body wt ip for 20 days), which reduced insulin sensitivity by 39.1%. Insulin sensitivity after l-NAME was not significantly different between BSO- and sham-treated animals. SIN-1 did not reverse the insulin resistance induced by l-NAME in the BSO-treated group. These results support our hypothesis that NO and GSH are essential for insulin action.
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Affiliation(s)
- Maria P Guarino
- Department of Physiology, Faculty of Medical Sciences, New University of Lisbon, Campo Mártires da Pátria 130, 1169-056 Lisbon, Portugal
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Evans JL, Goldfine ID, Maddux BA, Grodsky GM. Are oxidative stress-activated signaling pathways mediators of insulin resistance and beta-cell dysfunction? Diabetes 2003; 52:1-8. [PMID: 12502486 DOI: 10.2337/diabetes.52.1.1] [Citation(s) in RCA: 1022] [Impact Index Per Article: 48.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
In both type 1 and type 2 diabetes, diabetic complications in target organs arise from chronic elevations of glucose. The pathogenic effect of high glucose, possibly in concert with fatty acids, is mediated to a significant extent via increased production of reactive oxygen species (ROS) and reactive nitrogen species (RNS) and subsequent oxidative stress. ROS and RNS directly oxidize and damage DNA, proteins, and lipids. In addition to their ability to directly inflict damage on macromolecules, ROS and RNS indirectly induce damage to tissues by activating a number of cellular stress-sensitive pathways. These pathways include nuclear factor-kappaB, p38 mitogen-activated protein kinase, NH(2)-terminal Jun kinases/stress-activated protein kinases, hexosamines, and others. In addition, there is evidence that in type 2 diabetes, the activation of these same pathways by elevations in glucose and free fatty acid (FFA) levels leads to both insulin resistance and impaired insulin secretion. Therefore, we propose here that the hyperglycemia-induced, and possibly FFA-induced, activation of stress pathways plays a key role in the development of not only the late complications in type 1 and type 2 diabetes, but also the insulin resistance and impaired insulin secretion seen in type 2 diabetes.
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Affiliation(s)
- Joseph L Evans
- Medical Research Institute, San Francisco, California. University of California at San Francisco, San Francisco, California 94107, USA.
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Vasdev S, Gill V, Parai S, Longerich L, Gadag V. Dietary vitamin E and C supplementation prevents fructose induced hypertension in rats. Mol Cell Biochem 2002; 241:107-14. [PMID: 12482032 DOI: 10.1023/a:1020835229591] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In fructose-induced hypertension in Wistar-Kyoto (WKY) rats, excess endogenous aldehydes bind sulfhydryl groups of membrane proteins, altering membrane Ca2+ channels and increasing cytosolic free calcium and blood pressure. The thiol compound N-acetyl cysteine prevents fructose-induced hypertension by binding excess endogenous aldehydes and normalizing membrane Ca2+ channels and cytosolic free calcium. The aim of the present study was to investigate whether dietary supplementation of vitamin E and vitamin C which are known to increase tissue glutathione, a storage form of cysteine, prevents this hypertension and its associated biochemical and histopathological changes. Starting at 7 weeks of age, animals were divided into four groups of six animals each and treated as follows: control group, normal diet and normal drinking water; fructose group, normal diet and 4% fructose in drinking water; fructose + vitamin E group, diet supplemented with vitamin E (34 mg/ kg feed) and 4% fructose in drinking water; fructose + vitamin C group, diet supplemented with vitamin C (1,000 mg/kg feed) and 4% fructose in drinking water. At 14 weeks, systolic blood pressure, platelet [Ca2+]i and kidney and aortic aldehyde conjugates were significantly higher in the fructose group. These animals also displayed smooth muscle cell hyperplasia in the small arteries and arterioles of the kidneys. Dietary vitamin E and C supplementation in fructose-treated WKY rats prevented the increase in systolic blood pressure by normalizing cytosolic [Ca2+]i and kidney and aortic aldehyde conjugates and preventing adverse renal vascular changes.
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Affiliation(s)
- S Vasdev
- Department of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland, Canada.
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Effect of inhibition of glutathione synthesis on insulin action: in vivo and in vitro studies using buthionine sulfoximine. Biochem J 2001. [PMID: 10880357 DOI: 10.1042/0264-6021:3490579] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Decreased cellular GSH content is a common finding in experimental and human diabetes, in which increased oxidative stress appears to occur. Oxidative stress has been suggested to play a causative role in the development of impaired insulin action on adipose tissue and skeletal muscle. In this study we undertook to investigate the potential of GSH depletion to induce insulin resistance, by utilizing the GSH synthesis inhibitor, L-buthionine-[S,R]-sulfoximine (BSO). GSH depletion (20-80% in various tissues), was achieved in vivo by treating rats for 20 days with BSO, and in vitro (80%) by treating 3T3-L1 adipocytes with BSO for 18 h. No demonstrable change in the GSH/GSSG ratio was observed following BSO treatment. GSH depletion was progressively associated with abnormal glucose tolerance test, which could not be attributed to impaired insulin secretion. Skeletal muscle insulin responsiveness was unaffected by GSH depletion, based on normal glucose response to exogenous insulin, 2-deoxyglucose uptake measurements in isolated soleus muscle, and on normal skeletal muscle expression of GLUT4 protein. Adipocyte insulin responsiveness in vitro was assessed in 3T3-L1 adipocytes, which displayed decreased insulin-stimulated tyrosine phosphorylation of insulin-receptor-substrate proteins and of the insulin receptor, but exaggerated protein kinase B phosphorylation. However, insulin-stimulated glucose uptake was unaffected by GSH depletion. In accordance, normal adipose tissue insulin sensitivity was observed in BSO-treated rats in vivo, as demonstrated by normal inhibition of circulating non-esterified fatty acid levels by endogenous insulin secretion. In conclusion, GSH depletion by BSO results in impaired glucose tolerance, but preserved adipocyte and skeletal muscle insulin responsiveness. This suggests that alternative oxidation-borne factors mediate the induction of peripheral insulin resistance by oxidative stress.
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Vasdev S, Ford CA, Parai S, Longerich L, Gadag V. Dietary vitamin C supplementation lowers blood pressure in spontaneously hypertensive rats. Mol Cell Biochem 2001; 218:97-103. [PMID: 11330844 DOI: 10.1023/a:1007234027421] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
In spontaneously hypertensive rats (SHRs) excess endogenous aldehydes bind sulfhydryl groups of membrane proteins, altering membrane Ca2+ channels and increasing cytosolic free calcium and blood pressure. The thiol compound, N-acetyl cysteine, normalizes elevated blood pressure in SHRs by binding excess endogenous aldehydes. Vitamin C can increase tissue cysteine and glutathione levels. The aim of the present study was to investigate whether a dietary supplementation of vitamin C can lower tissue aldehydes and blood pressure and normalize associated biochemical and histopathological changes in SHRs. Starting at 12 weeks of age, animals were divided into 3 groups of 6 animals each. Animals in the WKY-control group and SHR-control group were given a normal diet and the SHR-vitamin C group a diet supplemented with vitamin C (1000 mg/kg feed) for the next 9 weeks. After nine weeks, systolic blood pressure, platelet [Ca2+]i, plasma insulin and liver, kidney and aortic aldehyde conjugates were significantly higher in SHR controls as compared to WKY controls and the SHR-vitamin C group. SHR-controls also showed smooth muscle cell hyperplasia in the small arteries and arterioles of the kidneys. Dietary vitamin C supplementation in SHRs lowered the systolic blood pressure, tissue aldehyde conjugates and attenuated adverse renal vascular changes.
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Affiliation(s)
- S Vasdev
- Department of Medicine, Health Sciences Centre, Memorial University of Newfoundland, St. John's, Canada
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Konukoğlu D, Hatemi H, Ozer EM, Gönen S, Akçay T. The erythrocyte glutathione levels during oral glucose tolerance test. J Endocrinol Invest 1997; 20:471-5. [PMID: 9364250 DOI: 10.1007/bf03348003] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Erythrocytes glutathione (GSH) levels were measured in erythrocytes from 33 subjects, at baseline and after 2-hour glucose loading in order to investigate the effect of glucose ingestion on the erythrocyte GSH. According to the World Health Organisation criteria 18 subjects had normal glucose tolerance (NGT)(mean age 48 +/- 10 years, 10 women, 8 men), 15 subjects had impaired glucose tolerance (IGT)(mean age 52 +/- 8 years, 9 women, 6 men). After 12-hour fasting, erythrocyte GSH levels were 40.5 +/- 8.06 and 39.27 +/- 10.26 mg/dl hemolisate in subjects with NGT and IGT, respectively (p = N.S). After 2-hour glucose loading, erythrocyte GSH levels decreased to 36.01 +/- 9.4 (p < 0.05) and 32.36 +/- 5.7 (p < 0.005) in subjects with NGT and IGT, respectively. The decrease in erythrocyte GSH levels in subjects with IGT was greater than in NGT individuals (p < 0.001). There was negative correlation between glucose, insulin, C-peptide, and erythrocyte GSH levels after glucose loading (p < 0.005). Our results suggest that glucose loading induce an oxidative stress in all subjects but this oxidative stress is greater in subjects with IGT than with NGT.
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Affiliation(s)
- D Konukoğlu
- Department of Biochemistry Cerrahpaşa Medical Faculty, Istanbul University, Turkey
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26
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Affiliation(s)
- G Paolisso
- Department of Geriatric Medicine and Metabolic Diseases, Second University of Naples, Italy
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Paolisso G, Gambardella A, Amato L, Tortoriello R, D'Amore A, Varricchio M, D'Onofrio F. Opposite effects of short- and long-term fatty acid infusion on insulin secretion in healthy subjects. Diabetologia 1995; 38:1295-9. [PMID: 8582538 DOI: 10.1007/bf00401761] [Citation(s) in RCA: 152] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Our study investigates short- and long-term effects of infusion of non-esterified fatty acids (NEFA) on insulin secretion in healthy subjects. Twelve healthy individuals underwent a 24-h Intralipid (10% triglyceride emulsion) infusion at a rate of 0.4 ml/min with a simultaneous infusion of heparin (a bolus of 200 U followed by 0.2 U/min per kg body weight). After an overnight fast (baseline), at 6 and at 24 h of Intralipid infusion and 24 h after Intralipid discontinuation (recovery test), all subjects underwent an intravenous glucose tolerance test (iv-GTT) (25 g of glucose/min). Intralipid infusion caused a threefold rise in plasma NEFA concentrations with no difference between the 6- and the 24-h concentrations. Compared to baseline acute insulin response (AIR) (AIR = 63 +/- 8 mU/l), short-term (6-h) Intralipid infusion was associated with a significant increase in AIR (86 +/- 12 mU/l p < 0.01); in contrast, long-term (24-h) Intralipid delivery was associated with inhibition of AIR (31 +/- 5 mU/l) compared to baseline (p < 0.001) and to the 6-h (p < 0.03) triglyceride emulsion infusion. Intralipid infusion was associated with a progressive and significant decline in respiratory quotient (RQ). A positive correlation between changes in fasting plasma NEFA concentrations and AIR at the 6-h infusion (r = 0.89 p < 0.001) was found. In contrast, at the end of the Intralipid infusion period, changes in plasma NEFA concentrations and AIR were negatively correlated (r = -0.87 p < 0.001). The recovery test showed that fasting plasma NEFA concentrations, RQ and AIR had returned to baseline values. In the control study (n = 8) 0.9% NaCl infusion did not mimick the effect of Intralipid. In conclusion, our study demonstrates that short- and long-term exposures of beta cells to high plasma NEFA concentrations have opposite effects on glucose-induced insulin secretion.
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Affiliation(s)
- G Paolisso
- Department of Geriatric Medicine and Metabolic Diseases, II University of Naples, Italy
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Paolisso G, Gambardella A, Saccomanno F, Varricchio G, D'Amore A, Varricchio M. Low-dose Iloprost infusion improves insulin action and non-oxidative glucose metabolism in hypertensive patients. Eur J Clin Pharmacol 1995; 48:333-8. [PMID: 8641319 DOI: 10.1007/bf00194947] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Fourteen hypertensive (174.3/98.3 mmHg) non-diabetic patients were given a euglyceamic glucose clamp along with infusion of 0.9% NaCl and the prostacyclin (PGI2) analogue Iloprost (0.7 ng x kg x min(-1)). Substrate oxidation was also determined by indirect calorimetry. Over the last 60 min of the clamp, Iloprost vs saline improved whole body glucose disposal (WBGD) (35 vs 28.3 micromol x kg(-1) LBM) and non-oxidative glucose metabolism (24.7 vs 18.1 micromol x kg(-1) LBM x min(-1). Iloprost delivery was associated with a significant decrease in membrane microviscosity (0.253 vs 0.205), but did not affect arterial blood pressure and heart rate. In nine patients, skeletal muscle blood flow (SMBF) and insulin-stimulated glucose uptake (GU) were also studied. At the end of the study, despite a similar SMBF (37 vs 38 ml x min(-1) x kg(-1)), GU (0.55 vs 0.46 mmol x l(-1)) was significantly increased by Iloprost infusion. Percentage decrease in membrane microviscosity was correlated with percentage increase in WBGD (r = 0.65) and non-oxidative glucose metabolism (r = 0.68). In conclusion, low-dose Iloprost infusion improves insulin action and non-oxidative glucose metabolism in hypertensive patients.
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Affiliation(s)
- G Paolisso
- Dipartimento di Geriatria e Malattie del Metabolismo, I Policlinico, Naples, Italy
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