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Smeijer JD, Kohan DE, Rossing P, Correa-Rotter R, Liew A, Tang SCW, de Zeeuw D, Gansevoort RT, Ju W, Lambers Heerspink HJ. Insulin resistance, kidney outcomes and effects of the endothelin receptor antagonist atrasentan in patients with type 2 diabetes and chronic kidney disease. Cardiovasc Diabetol 2023; 22:251. [PMID: 37716952 PMCID: PMC10505320 DOI: 10.1186/s12933-023-01964-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 08/14/2023] [Indexed: 09/18/2023] Open
Abstract
BACKGROUND Insulin resistance (IR) is a pathophysiologic hallmark of type 2 diabetes and associated with the presence of chronic kidney disease (CKD). Experimental studies suggest that endothelin-1 increases IR. We assessed the association between IR and cardio-renal outcomes and the effect of the selective endothelin receptor antagonist atrasentan on IR in patients with type 2 diabetes and CKD. METHODS We used data from the RADAR and SONAR trials that recruited participants with type 2 diabetes and CKD [eGFR 25-75 mL/min/1.73 m², urine albumin-to-creatinine ratio of 300-5000 mg/g]. IR was calculated using the homeostatic model assessment (HOMA-IR). The association between HOMA-IR and the pre-specified cardio-renal outcomes was assessed using multivariable Cox proportional hazards regression, and effects of atrasentan on HOMA-IR by a linear mixed effect model. RESULTS In the SONAR trial, each log-unit increase in HOMA-IR was associated with an increased risk of the composite cardio-renal outcome [hazard ratio 1.32 (95%CI 1.09,1.60; p = 0.004)], kidney outcome [hazard ratio 1.30 (95%CI 1.00,1.68; p-value = 0.048)], and the kidney or all-cause mortality outcome [hazard ratio 1.25 (95%CI 1.01,1.55; p-value = 0.037)]. After 12 weeks treatment in the RADAR trial (N = 123), atrasentan 0.75 mg/day and 1.25 mg/day compared to placebo reduced HOMA-IR by 19.1 (95%CI -17.4, 44.3) and 26.7% (95%CI -6.4, 49.5), respectively. In the SONAR trial (N = 1914), atrasentan 0.75 mg/day compared to placebo reduced HOMA-IR by 9.6% (95%CI 0.6, 17.9). CONCLUSIONS More severe IR is associated with increased risk of cardio-renal outcomes. The endothelin receptor antagonist atrasentan reduced IR. TRIAL REGISTRATION RADAR trial (Reducing Residual Albuminuria in Subjects With Diabetes and Nephropathy With AtRasentan): NCT01356849. SONAR trial (The Study Of Diabetic Nephropathy With AtRasentan) NCT01858532.
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Affiliation(s)
- J David Smeijer
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Donald E Kohan
- Division of Nephrology, University of Utah Health, Salt Lake City, UT, USA
| | - Peter Rossing
- Steno Diabetes Center Copenhagen, Herlev, Denmark
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Ricardo Correa-Rotter
- National Medical Science and Nutrition Institute Salvador Zubirán, Mexico City, Mexico
| | - Adrian Liew
- Mount Elizabeth Novena Hospital, Singapore, Singapore
- George Institute for Global Health, Newtown, Australia
| | - Sydney C W Tang
- Division of Nephrology, Department of Medicine, The University of Hong Kong, Hong Kong, Hong Kong
| | - Dick de Zeeuw
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Ron T Gansevoort
- Department of Internal Medicine, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Wenjun Ju
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Hiddo J Lambers Heerspink
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
- George Institute for Global Health, Newtown, Australia.
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2
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Derella CC, Blanks AM, Nguyen A, Looney J, Tucker MA, Jeong J, Rodriguez-Miguelez P, Thomas J, Lyon M, Pollock DM, Harris RA. Dual endothelin receptor antagonism increases resting energy expenditure in people with increased adiposity. Am J Physiol Endocrinol Metab 2022; 322:E508-E516. [PMID: 35373585 PMCID: PMC9126219 DOI: 10.1152/ajpendo.00349.2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 03/22/2022] [Accepted: 03/29/2022] [Indexed: 01/18/2023]
Abstract
Increased adiposity is associated with dysregulation of the endothelin system, both of which increase the risk of cardiovascular disease (CVD). Preclinical data indicate that endothelin dysregulation also reduces resting energy expenditure (REE). The objective was to test the hypothesis that endothelin receptor antagonism will increase REE in people with obesity compared with healthy weight individuals. Using a double blind, placebo-controlled, crossover design, 32 participants [healthy weight (HW): n = 16, BMI: 21.3 ± 2.8 kg/m2, age: 26 ± 7 yr and overweight/obese (OB): n = 16, BMI: 33.5 ± 9.5 kg/m2, age: 31 ± 6 yr] were randomized to receive either 125 mg of bosentan (ETA/B antagonism) or placebo twice per day for 3 days. Breath-by-breath gas exchange data were collected and REE was assessed by indirect calorimetry. Venous blood samples were analyzed for concentrations of endothelin-1 (ET-1). Treatment with bosentan increased plasma ET-1 in both OB and HW groups. Within the OB group, the changes in absolute REE (PLA: -77.6 ± 127.6 vs. BOS: 72.2 ± 146.6 kcal/day; P = 0.046). The change in REE was not different following either treatment in the HW group. Overall, absolute plasma concentrations of ET-1 following treatment with bosentan were significantly associated with kcal/day of fat (r = 0.488, P = 0.005), percentage of fat utilization (r = 0.415, P = 0.020), and inversely associated with the percentage of carbohydrates (r = -0.419, P = 0.019), and respiratory exchange ratio (r = -0.407, P = 0.023). Taken together, these results suggest that modulation of the endothelin system may represent a novel therapeutic approach to increase both resting metabolism and caloric expenditure, and reduce CVD risk in people with increased adiposity.NEW & NOTEWORTHY Findings from our current translational investigation demonstrate that dual endothelin A/B receptor antagonism increases total REE in overweight/obese individuals. These results suggest that modulation of the endothelin system may represent a novel therapeutic target to increase both resting metabolism and caloric expenditure, enhance weight loss, and reduce CVD risk in seemingly healthy individuals with elevated adiposity.
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Affiliation(s)
- Cassandra C Derella
- Department of Medicine, Georgia Prevention Institute, Augusta University, Augusta, Georgia
| | - Anson M Blanks
- Department of Medicine, Georgia Prevention Institute, Augusta University, Augusta, Georgia
| | - Andy Nguyen
- Medical College of Georgia, Augusta University, Augusta, Georgia
| | - Jacob Looney
- Department of Medicine, Georgia Prevention Institute, Augusta University, Augusta, Georgia
| | - Matthew A Tucker
- Department of Medicine, Georgia Prevention Institute, Augusta University, Augusta, Georgia
| | - Jinhee Jeong
- Department of Medicine, Georgia Prevention Institute, Augusta University, Augusta, Georgia
| | - Paula Rodriguez-Miguelez
- Department of Medicine, Georgia Prevention Institute, Augusta University, Augusta, Georgia
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, Virginia
| | - Jeffrey Thomas
- Department of Medicine, Georgia Prevention Institute, Augusta University, Augusta, Georgia
| | - Matthew Lyon
- Medical College of Georgia, Augusta University, Augusta, Georgia
| | - David M Pollock
- Cardio-Renal Physiology and Medicine Section, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | - Ryan A Harris
- Department of Medicine, Georgia Prevention Institute, Augusta University, Augusta, Georgia
- Sport and Exercise Science Research Institute, Ulster University, Jordanstown, United Kingdom
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3
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Young BE, Padilla J, Finsen SH, Fadel PJ, Mortensen SP. Role of Endothelin-1 Receptors in Limiting Leg Blood Flow and Glucose Uptake During Hyperinsulinemia in Type 2 Diabetes. Endocrinology 2022; 163:6515918. [PMID: 35084435 PMCID: PMC8852254 DOI: 10.1210/endocr/bqac008] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Indexed: 01/29/2023]
Abstract
Skeletal muscle insulin resistance is a hallmark of individuals with type 2 diabetes mellitus (T2D). In healthy individuals insulin stimulates vasodilation, which is markedly blunted in T2D; however, the mechanism(s) remain incompletely understood. Investigations in rodents indicate augmented endothelin-1 (ET-1) action as a major contributor. Human studies have been limited to young obese participants and focused exclusively on the ET-1 A (ETA) receptor. Herein, we have hypothesized that ETA receptor antagonism would improve insulin-stimulated vasodilation and glucose uptake in T2D, with further improvements observed during concurrent ETA + ET-1 B (ETB) antagonism. Arterial pressure (arterial line), leg blood flow (LBF; Doppler), and leg glucose uptake (LGU) were measured at rest, during hyperinsulinemia alone, and hyperinsulinemia with (1) femoral artery infusion of BQ-123, the selective ETA receptor antagonist (n = 10 control, n = 9 T2D) and then (2) addition of BQ-788 (selective ETB antagonist) for blockade of ETA and ETB receptors (n = 7 each). The LBF responses to hyperinsulinemia alone tended to be lower in T2D (controls: ∆161 ± 160 mL/minute; T2D: ∆58 ± 43 mL/minute, P = .08). BQ-123 during hyperinsulinemia augmented LBF to a greater extent in T2D (% change: controls: 14 ± 23%; T2D: 38 ± 21%, P = .029). LGU following BQ-123 increased similarly between groups (P = .85). Concurrent ETA + ETB antagonism did not further increase LBF or LGU in either group. Collectively, these findings suggest that during hyperinsulinemia ETA receptor activation restrains vasodilation more in T2D than controls while limiting glucose uptake similarly in both groups, with no further effect of ETB receptors (NCT04907838).
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Affiliation(s)
- Benjamin E Young
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX 76019, USA
- Correspondence: Benjamin E. Young, PhD, Department of Kinesiology, College of Nursing and Health Innovation, University of Texas at Arlington, 411 S. Nedderman Dr., Pickard Hall, room 504, Arlington, TX 76019, USA.
| | - Jaume Padilla
- Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, MO 65211, USA
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO 65211, USA
| | - Stine H Finsen
- Department of Cardiovascular and Renal Research, University of Southern Denmark, Odense, Denmark
| | - Paul J Fadel
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX 76019, USA
| | - Stefan P Mortensen
- Department of Cardiovascular and Renal Research, University of Southern Denmark, Odense, Denmark
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Feng L, Wang S, Chen F, Zhang C, Wang Q, Zhao Y, Zhang Z. Hepatic Knockdown of Endothelin Type A Receptor (ETAR) Ameliorates Hepatic Insulin Resistance and Hyperglycemia Through Suppressing p66Shc-Mediated Mitochondrial Fragmentation in High-Fat Diet-Fed Mice. Diabetes Metab Syndr Obes 2021; 14:963-981. [PMID: 33688230 PMCID: PMC7936928 DOI: 10.2147/dmso.s299570] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 02/23/2021] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Emerging evidence from animal studies and clinical trials indicates that systemic inhibition of endothelin1 (ET1) signaling by endothelin receptor antagonists improves pathological features of diabetes and its complications. It is indicated that endothelin type A receptor (ETAR) plays a major role in ET1-mediated pathophysiological actions including diabetic pathology. However, the effects as well as the mechanistic targets of hepatic ET1/ETAR signaling inhibition on the pathology of metabolic diseases remain unclear. This study aimed to investigate the beneficial effects as well as the underlying mechanisms of hepatic ETAR knockdown on metabolism abnormalities in high-fat diet (HFD)-fed mice. METHODS Mice were fed a HFD to induce insulin resistance and metabolism abnormalities. L02 cells were treated with ET1 to assess the action of ET1/ETAR signaling in vitro. Liver-selective knockdown of ETAR was achieved by tail vein injection of adeno-associated virus 8 (AAV8). Systemic and peripheral metabolism abnormalities were determined in vivo and in vitro. Mitochondrial fragmentation was observed by transmission electron microscope (TEM) and mitoTracker red staining. RESULTS Here we provided in vivo and in vitro evidence to demonstrate that liver-selective knockdown of ETAR effectively ameliorated hepatic insulin resistance and hyperglycemia in HFD-fed mice. Mechanistically, hepatic ETAR knockdown alleviated mitochondrial fragmentation and dysfunction via inactivating 66-kDa Src homology 2 domain-containing protein (p66Shc) to recover mitochondrial dynamics, which was mediated by inhibiting protein kinase Cδ (PKCδ), in the livers of HFD-fed mice. Ultimately, hepatic ETAR knockdown attenuated mitochondria-derived oxidative stress and related liver injuries in HFD-fed mice. These ETAR knockdown-mediated actions were confirmed in ET1-treated L02 cells. CONCLUSION This study defined an ameliorative role of hepatic ETAR knockdown in HFD-induced metabolism abnormalities by alleviating p66Shc-mediated mitochondrial fragmentation and consequent oxidative stress-related disorders and indicated that hepatic ETAR knockdown may be a promising therapeutic strategy for metabolic diseases.
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Affiliation(s)
- Li Feng
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, 221116, People’s Republic of China
| | - Songhua Wang
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, 221116, People’s Republic of China
| | - Feng Chen
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, 221116, People’s Republic of China
| | - Cheng Zhang
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, 221116, People’s Republic of China
| | - Qiao Wang
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, 221116, People’s Republic of China
| | - Yuting Zhao
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, 221116, People’s Republic of China
| | - Zifeng Zhang
- School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, 221116, People’s Republic of China
- Correspondence: Zifeng Zhang 101 Shanghai Road, Xuzhou, Jiangsu Province, 221116, People’s Republic of ChinaTel + 86 516 83403729 Email
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Heerspink HJL, Kohan DE, de Zeeuw D. New insights from SONAR indicate adding sodium glucose co-transporter 2 inhibitors to an endothelin receptor antagonist mitigates fluid retention and enhances albuminuria reduction. Kidney Int 2020; 99:346-349. [PMID: 33144213 DOI: 10.1016/j.kint.2020.09.026] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 08/20/2020] [Accepted: 09/16/2020] [Indexed: 12/22/2022]
Abstract
The diuretic effects achieved with sodium glucose co-transporter 2 inhibitors (SGLT2i) may offset fluid retaining effects of the endothelin receptor antagonist (ERA) atrasentan while effects on albuminuria and kidney protection of both drug classes may be complimentary due to distinct mechanisms of action. Here, post-hoc analysis of the SONAR trial, in patients with type 2 diabetes and chronic kidney disease, show that six-weeks treatment with combined SGLT2i/atrasentan versus atrasentan alone decreased body weight, a surrogate for fluid retention, and further decreased albuminuria. Thus, these promising findings support future clinical studies to characterize the long-term efficacy and safety of combined SGLT2i/ERA treatment.
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Affiliation(s)
- Hiddo J L Heerspink
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
| | - Donald E Kohan
- Division of Nephrology, University of Utah, Salt Lake City, Utah, USA
| | - Dick de Zeeuw
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
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Muniyappa R, Chen H, Montagnani M, Sherman A, Quon MJ. Endothelial dysfunction due to selective insulin resistance in vascular endothelium: insights from mechanistic modeling. Am J Physiol Endocrinol Metab 2020; 319:E629-E646. [PMID: 32776829 PMCID: PMC7642854 DOI: 10.1152/ajpendo.00247.2020] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Previously, we have used mathematical modeling to gain mechanistic insights into insulin-stimulated glucose uptake. Phosphatidylinositol 3-kinase (PI3K)-dependent insulin signaling required for metabolic actions of insulin also regulates endothelium-dependent production of the vasodilator nitric oxide (NO). Vasodilation increases blood flow that augments direct metabolic actions of insulin in skeletal muscle. This is counterbalanced by mitogen-activated protein kinase (MAPK)-dependent insulin signaling in endothelium that promotes secretion of the vasoconstrictor endothelin-1 (ET-1). In the present study, we extended our model of metabolic insulin signaling into a dynamic model of insulin signaling in vascular endothelium that explicitly represents opposing PI3K/NO and MAPK/ET-1 pathways. Novel NO and ET-1 subsystems were developed using published and new experimental data to generate model structures/parameters. The signal-response relationships of our model with respect to insulin-stimulated NO production, ET-1 secretion, and resultant vascular tone, agree with published experimental data, independent of those used for model development. Simulations of pathological stimuli directly impairing only insulin-stimulated PI3K/Akt activity predict altered dynamics of NO and ET-1 consistent with endothelial dysfunction in insulin-resistant states. Indeed, modeling pathway-selective impairment of PI3K/Akt pathways consistent with insulin resistance caused by glucotoxicity, lipotoxicity, or inflammation predict diminished NO production and increased ET-1 secretion characteristic of diabetes and endothelial dysfunction. We conclude that our mathematical model of insulin signaling in vascular endothelium supports the hypothesis that pathway-selective insulin resistance accounts, in part, for relationships between insulin resistance and endothelial dysfunction. This may be relevant for developing novel approaches for the treatment of diabetes and its cardiovascular complications.
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Affiliation(s)
- Ranganath Muniyappa
- Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland
| | - Hui Chen
- Clinical and Integrative Diabetes and Obesity Integrated Review Group, Center for Scientific Review, National Institutes of Health, Bethesda, Maryland
| | - Monica Montagnani
- Department of Biomedical Sciences and Human Oncology, Pharmacology Section, Medical School, University of Bari "Aldo Moro", Bari, Italy
| | - Arthur Sherman
- Laboratory of Biological Modeling, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland
| | - Michael J Quon
- Laboratory of Biological Modeling, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland
- Division of Endocrinology, Diabetes, and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
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Schinzari F, Tesauro M, Cardillo C. Increased endothelin-1-mediated vasoconstrictor tone in human obesity: effects of gut hormones. Physiol Res 2018; 67:S69-S81. [PMID: 29947529 DOI: 10.33549/physiolres.933821] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The heavy impact of obesity on the development and progression of cardiovascular disease has sparked sustained efforts to uncover the mechanisms linking excess adiposity to vascular dysfunction. Impaired vasodilator reactivity has been recognized as an early hemodynamic abnormality in obese patients, but also increased vasoconstrictor tone importantly contributes to their vascular damage. In particular, upregulation of the endothelin (ET)-1 system, consistently reported in these patients, might accelerate atherosclerosis and its complication, given the pro-inflammatory and mitogenic properties of ET-1. In recent years, a number of gut hormones, in addition to their role as modulators of food intake, energy balance, glucose and lipid metabolism, and insulin secretion and action, have demonstrated favorable vascular actions. They increase the bioavailability of vasodilator mediators like nitric oxide, but they have also been shown to inhibit the ET-1 system. These features make gut hormones promising tools for targeting both the metabolic and cardiovascular complications of obesity, a view supported by recent large-scale clinical trials indicating that novel drugs for type 2 diabetes with cardiovascular potential may translate into clinically significant advantages. Therefore, there is real hope that better understanding of the properties of gut-derived substances might provide more effective therapies for the obesity-related cardiometabolic syndrome.
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Affiliation(s)
- F Schinzari
- Policlinico A. Gemelli, Rome, Italy, Istituto di Patologia Speciale Medica e Semeiotica Medica, Universita Cattolica del Sacro Cuore, Rome, Italy.
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Polak J, Punjabi NM, Shimoda LA. Blockade of Endothelin-1 Receptor Type B Ameliorates Glucose Intolerance and Insulin Resistance in a Mouse Model of Obstructive Sleep Apnea. Front Endocrinol (Lausanne) 2018; 9:280. [PMID: 29896159 PMCID: PMC5986958 DOI: 10.3389/fendo.2018.00280] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Accepted: 05/11/2018] [Indexed: 01/17/2023] Open
Abstract
Obstructive sleep apnea (OSA) is associated with insulin resistance (IR) and glucose intolerance. Elevated endothelin-1 (ET-1) levels have been observed in OSA patients and in mice exposed to intermittent hypoxia (IH). We examined whether pharmacological blockade of type A and type B ET-1 receptors (ETA and ETB) would ameliorate glucose intolerance and IR in mice exposed to IH. Subcutaneously implanted pumps delivered BQ-123 (ETA antagonist; 200 nmol/kg/day), BQ-788 (ETB antagonist; 200 nmol/kg/day) or vehicle (saline or propyleneglycol [PG]) for 14 days in C57BL6/J mice (10/group). During treatment, mice were exposed to IH (decreasing the FiO2 from 20.9% to 6%, 60/h) or intermittent air (IA). After IH or IA exposure, insulin (0.5 IU/kg) or glucose (1 mg/kg) was injected intraperitoneally and plasma glucose determined after injection and area under glucose curve (AUC) was calculated. Fourteen-day IH increased fasting glucose levels (122 ± 7 vs. 157 ± 8 mg/dL, PG: 118 ± 6 vs. 139 ± 8; both p < 0.05) and impaired glucose tolerance (AUCglucose: 19,249 ± 1105 vs. 29,124 ± 1444, PG AUCglucose: 18,066 ± 947 vs. 25,135 ± 797; both p < 0.05) in vehicle-treated animals. IH-induced impairments in glucose tolerance were partially ameliorated with BQ-788 treatment (AUCglucose: 21,969 ± 662; p < 0.05). Fourteen-day IH also induced IR (AUCglucose: 7185 ± 401 vs. 8699 ± 401; p < 0.05). Treatment with BQ-788 decreased IR under IA (AUCglucose: 5281 ± 401, p < 0.05) and reduced worsening of IR with IH (AUCglucose: 7302 ± 401, p < 0.05). There was no effect of BQ-123 on IH-induced impairments in glucose tolerance or IR. Our results suggest that ET-1 plays a role in IH-induced impairments in glucose homeostasis.
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Affiliation(s)
- Jan Polak
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, United States
- Department for the Study of Obesity and Diabetes, Third Faculty of Medicine, Charles University, Prague, Czechia
| | - Naresh M. Punjabi
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, United States
| | - Larissa A. Shimoda
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, United States
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Khuu LA, Tayyari F, Sivak JM, Flanagan JG, Singer S, Brent MH, Huang D, Tan O, Hudson C. Aqueous humor endothelin-1 and total retinal blood flow in patients with non-proliferative diabetic retinopathy. Eye (Lond) 2017; 31:1443-1450. [PMID: 28548649 DOI: 10.1038/eye.2017.74] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2015] [Accepted: 03/14/2017] [Indexed: 12/16/2022] Open
Abstract
PurposeThe purpose of this study was to determine the association between aqueous ET-1 levels and total retinal blood flow (TRBF) in patients with non-insulin-dependent type 2 diabetes mellitus (T2DM) and early non-proliferative diabetic retinopathy (NPDR).Patients and methodsA total of 15 age-matched controls and 15 T2DM patients with NPDR were recruited into the study. Aqueous humor (~80-120 μl) was collected before cataract surgery to measure the levels of ET-1 using suspension multiplex array technology. Four weeks post surgery, six images were acquired to assess TRBF using the prototype RTVue Doppler FD-OCT (Optovue, Inc., Fremont, CA, USA) with a double circular scan protocol. At the same visit, forearm blood was collected to determine plasma glycosylated hemoglobin (A1c) levels.ResultsAqueous ET-1 was significantly elevated in the NPDR group compared with the control group (3.5±1.8 vs 2.2±0.8, P=0.02). TRBF was found to be significantly reduced in the NPDR group compared with the control group (34.5±9.1 vs 44.1±4.6 μl/min, P=0.002). TRBF and aqueous ET-1 were not correlated within the NPDR group (r=-0.24, P=0.22). In a multivariate analysis, high A1c was associated with reduced TRBF and aqueous ET-1 levels across control and NPDR groups (P<0.01).ConclusionAqueous ET-1 levels were increased while TRBF was reduced in patients with NPDR compared with the control group. Although not directly associated, the vasoconstrictory effects of ET-1 are consistent with a reduced TRBF observed in early DR. ET-1 dysregulation may contribute to a reduction in retinal blood flow during early DR.
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Affiliation(s)
- L-A Khuu
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada.,Vision Science and Ophthalmology, Toronto Western Hospital, Toronto, ON, Canada
| | - F Tayyari
- School of Optometry and Vision Science, University of Waterloo, Waterloo, ON, Canada
| | - J M Sivak
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - J G Flanagan
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada.,Vision Science and Ophthalmology, Toronto Western Hospital, Toronto, ON, Canada.,School of Optometry and Vision Science, University of Waterloo, Waterloo, ON, Canada
| | - S Singer
- Vision Science and Ophthalmology, Toronto Western Hospital, Toronto, ON, Canada
| | - M H Brent
- Vision Science and Ophthalmology, Toronto Western Hospital, Toronto, ON, Canada
| | - D Huang
- Casey Eye Institute, Oregon Health and Science University, Portland, OR, USA
| | - O Tan
- Casey Eye Institute, Oregon Health and Science University, Portland, OR, USA
| | - C Hudson
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada.,Vision Science and Ophthalmology, Toronto Western Hospital, Toronto, ON, Canada.,School of Optometry and Vision Science, University of Waterloo, Waterloo, ON, Canada
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10
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Park CB, Ahn CM, Oh S, Kwon D, Cho WC, Shin WS, Cui Y, Um YS, Park BG, Lee S. Synthesis of alkylsulfonyl and substituted benzenesulfonyl curcumin mimics as dual antagonist of L-type Ca(2+) channel and endothelin A/B2 receptor. Bioorg Med Chem 2015; 23:6673-82. [PMID: 26386817 DOI: 10.1016/j.bmc.2015.09.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 09/03/2015] [Accepted: 09/04/2015] [Indexed: 12/01/2022]
Abstract
We synthesized a library of curcumin mimics with diverse alkylsulfonyl and substituted benzenesulfonyl modifications through a simple addition reaction of important intermediate, 1-(3-Amino-phenyl)-3-(4-hydroxy-3-methoxy-phenyl)-propenone (10), with various sulfonyl chloride reactants and then tested their vasodilatation effect on depolarization (50 mM K(+))- and endothelin-1 (ET-1)-induced basilar artery contraction. Generally, curcumin mimics with aromatic sulfonyl groups showed stronger vasodilation effect than alkyl sulfonylated curcumin mimics. Among the tested compounds, six curcumin mimics (11g, 11h, 11i, 11j, 11l, and 11s) in a depolarization-induced vasoconstriction and seven compounds (11g, 11h, 11i, 11j, 11l, 11p, and 11s) in an ET-1-induced vasoconstriction showed strong vasodilation effect. Based on their biological properties, synthetic curcumin mimics can act as dual antagonist scaffold of L-type Ca(2+) channel and endothelin A/B2 receptor in vascular smooth muscle cells. In particular, compounds 11g and 11s are promising novel drug candidates to treat hypertension related to the overexpression of L-type Ca(2+) channels and ET peptides/receptors-mediated cardiovascular diseases.
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Affiliation(s)
- Chong-Bin Park
- Department of Thoracic and Cardiovascular Surgery, Gangneung Asan Hospital, Ulsan University College of Medicine, Gangneung 210-711, Republic of Korea
| | - Chan Mug Ahn
- Department of Basic Science, Yonsei University Wonju College of Medicine, Wonju 220-701, Republic of Korea
| | - Sangtae Oh
- Department of Basic Science, Catholic Kwandong University College of Medicine, Gangneung 210-701, Republic of Korea
| | - Daeho Kwon
- Department of Microbiology, Catholic Kwandong University College of Medicine, Gangneung 210-701, Republic of Korea; Institute for Clinical and Translational Research, Catholic Kwandong University College of Medicine, Gangneung 210-701, Republic of Korea
| | - Won-Chul Cho
- Department of Thoracic and Cardiovascular Surgery, Gangneung Asan Hospital, Ulsan University College of Medicine, Gangneung 210-711, Republic of Korea
| | - Woon-Seob Shin
- Department of Microbiology, Catholic Kwandong University College of Medicine, Gangneung 210-701, Republic of Korea; Institute for Clinical and Translational Research, Catholic Kwandong University College of Medicine, Gangneung 210-701, Republic of Korea
| | - Yuan Cui
- Department of Physiology, Catholic Kwandong University College of Medicine, Gangneung 210-701, Republic of Korea
| | - Ye Sol Um
- Department of Physiology, Catholic Kwandong University College of Medicine, Gangneung 210-701, Republic of Korea
| | - Byong-Gon Park
- Institute for Clinical and Translational Research, Catholic Kwandong University College of Medicine, Gangneung 210-701, Republic of Korea; Department of Physiology, Catholic Kwandong University College of Medicine, Gangneung 210-701, Republic of Korea.
| | - Seokjoon Lee
- Institute for Clinical and Translational Research, Catholic Kwandong University College of Medicine, Gangneung 210-701, Republic of Korea; Department of Pharmacology, Catholic Kwandong University College of Medicine, Gangneung 210-701, Republic of Korea.
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11
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Campia U, Tesauro M, Di Daniele N, Cardillo C. The vascular endothelin system in obesity and type 2 diabetes: Pathophysiology and therapeutic implications. Life Sci 2014; 118:149-55. [DOI: 10.1016/j.lfs.2014.02.028] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2013] [Revised: 02/05/2014] [Accepted: 02/20/2014] [Indexed: 12/29/2022]
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Matsumoto T, Lopes RAM, Taguchi K, Kobayashi T, Tostes RC. Linking the beneficial effects of current therapeutic approaches in diabetes to the vascular endothelin system. Life Sci 2014; 118:129-35. [PMID: 24418002 DOI: 10.1016/j.lfs.2013.12.216] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Revised: 12/04/2013] [Accepted: 12/24/2013] [Indexed: 12/19/2022]
Abstract
The rising epidemic of diabetes worldwide is of significant concern. Although the ultimate objective is to prevent the development and find a cure for the disease, prevention and treatment of diabetic complications is very important. Vascular complications in diabetes, or diabetic vasculopathy, include macro- and microvascular dysfunction and represent the principal cause of morbidity and mortality in diabetic patients. Endothelial dysfunction plays a pivotal role in the development and progression of diabetic vasculopathy. Endothelin-1 (ET-1), an endothelial cell-derived peptide, is a potent vasoconstrictor with mitogenic, pro-oxidative and pro-inflammatory properties that are particularly relevant to the pathophysiology of diabetic vasculopathy. Overproduction of ET-1 is reported in patients and animal models of diabetes and the functional effects of ET-1 and its receptors are also greatly altered in diabetic conditions. The current therapeutic approaches in diabetes include glucose lowering, sensitization to insulin, reduction of fatty acids and vasculoprotective therapies. However, whether and how these therapeutic approaches affect the ET-1 system remain poorly understood. Accordingly, in the present review, we will focus on experimental and clinical evidence that indicates a role for ET-1 in diabetic vasculopathy and on the effects of current therapeutic approaches in diabetes on the vascular ET-1 system.
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Affiliation(s)
- Takayuki Matsumoto
- Department of Physiology and Morphology, Institute of Medicinal Chemistry, Hoshi University, Shinagawa-ku, Tokyo 142-8501, Japan.
| | - Rheure A M Lopes
- Department of Pharmacology, Medical School of Ribeirao Preto, University of Sao Paulo, Av Bandeirantes 3900, Ribeirao Preto, SP 14049-900, Brazil
| | - Kumiko Taguchi
- Department of Physiology and Morphology, Institute of Medicinal Chemistry, Hoshi University, Shinagawa-ku, Tokyo 142-8501, Japan
| | - Tsuneo Kobayashi
- Department of Physiology and Morphology, Institute of Medicinal Chemistry, Hoshi University, Shinagawa-ku, Tokyo 142-8501, Japan
| | - Rita C Tostes
- Department of Pharmacology, Medical School of Ribeirao Preto, University of Sao Paulo, Av Bandeirantes 3900, Ribeirao Preto, SP 14049-900, Brazil
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13
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Abstract
Insulin resistance affects the vascular endothelium, and contributes to systemic insulin resistance by directly impairing the actions of insulin to redistribute blood flow as part of its normal actions driving muscle glucose uptake. Impaired vascular function is a component of the insulin resistance syndrome, and is a feature of type 2 diabetes. On this basis, the vascular endothelium has emerged as a therapeutic target where the intent is to improve systemic metabolic state by improving vascular function. We review the available literature presenting studies in humans, evaluating the effects of metabolically targeted and vascular targeted therapies on insulin action and systemic metabolism. Therapies that improve systemic insulin resistance exert strong concurrent effects to improve vascular function and vascular insulin action. RAS-acting agents and statins have widely recognized beneficial effects on vascular function but have not uniformly produced the hoped-for metabolic benefits. These observations support the notion that systemic metabolic benefits can arise from therapies targeted at the endothelium, but improving vascular insulin action does not result from all treatments that improve endothelium-dependent vasodilation. A better understanding of the mechanisms of insulin's actions in the vascular wall will advance our understanding of the specificity of these responses, and allow us to better target the vasculature for metabolic benefits.
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Affiliation(s)
- Kieren J Mather
- Indiana University School of Medicine, Indianapolis, IN 46202, USA.
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14
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Eringa EC, Serne EH, Meijer RI, Schalkwijk CG, Houben AJHM, Stehouwer CDA, Smulders YM, van Hinsbergh VWM. Endothelial dysfunction in (pre)diabetes: characteristics, causative mechanisms and pathogenic role in type 2 diabetes. Rev Endocr Metab Disord 2013; 14:39-48. [PMID: 23417760 DOI: 10.1007/s11154-013-9239-7] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Endothelial dysfunction associated with diabetes and cardiovascular disease is characterized by changes in vasoregulation, enhanced generation of reactive oxygen intermediates, inflammatory activation, and altered barrier function. These endothelial alterations contribute to excess cardiovascular disease in diabetes, but may also play a role in the pathogenesis of diabetes, especially type 2. The mechanisms underlying endothelial dysfunction in diabetes differ between type 1 (T1D) and type 2 diabetes (T2D): hyperglycemia contributes to endothelial dysfunction in all individuals with diabetes, whereas the causative mechanisms in T2D also include impaired insulin signaling in endothelial cells, dyslipidemia and altered secretion of bioactive substances (adipokines) by adipose tissue. The close association of so-called perivascular adipose tissue with arteries and arterioles facilitates the exposure of vascular endothelium to adipokines, particularly if inflammation activates the adipose tissue. Glucose and adipokines activate specific intracellular signaling pathways in endothelium, which in concert result in endothelial dysfunction in diabetes. Here, we review the characteristics of endothelial dysfunction in diabetes, the causative mechanisms involved and the role of endothelial dysfunction(s) in the pathogenesis of T2D. Finally, we will discuss the therapeutic potential of endothelial dysfunction in T2D.
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Affiliation(s)
- Etto C Eringa
- Departments of Physiology, VU University Medical Center, Amsterdam, the Netherlands.
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15
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Abstract
Metabolic syndrome is highly prevalent in vascular patients and has a significant impact on the outcomes of vascular interventions. It comprises of a set of metabolically driven risk factors, including truncal obesity, dyslipidemia, elevated blood pressure and elevated fasting blood glucose. Increased insulin resistance within the context of obesity and hypertension contributes to atherogenic dyslipidemia, hyperglycemia, and prothrombotic and proinflammatory states which lead to the adverse impact of metabolic syndrome on the response to injury and on atherosclerotic disease progression. This review focuses on the complex biology of metabolic syndrome and its relevance to management of vascular patients, including outcomes and implications for the coronary, cerebrovascular and lower-extremity vascular beds.
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Affiliation(s)
- Daynene Vykoukal
- Vascular Biology and Therapeutics Program, The Methodist Hospital Research Institute, Houston, TX 77030, USA
| | - Mark G Davies
- Vascular Biology and Therapeutics Program, The Methodist Hospital Research Institute, Houston, TX 77030, USA
- Department of Cardiovascular Surgery, Methodist DeBakey Heart & Vascular Center, The Methodist Hospital,Houston, TX 77030, USA
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16
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Obesity and airway responsiveness: role of TNFR2. Pulm Pharmacol Ther 2012; 26:444-54. [PMID: 22584291 DOI: 10.1016/j.pupt.2012.05.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 04/30/2012] [Accepted: 05/02/2012] [Indexed: 01/13/2023]
Abstract
Obese mice exhibit innate airway hyperresponsiveness (AHR), a feature of asthma. Tumor necrosis factor alpha (TNFα) is implicated in the disease progression and chronic inflammatory status of both obesity and asthma. TNF acts via two TNF receptors, TNFR1 and TNFR2. To examine the role of TNFR2 in the AHR observed in obese mice, we generated obese Cpe(fat) mice that were either sufficient or deficient in TNFR2 (Cpe(fat) and Cpe(fat)/TNFR2(-/-) mice, respectively) and compared them with their lean controls (WT and TNFR2(-/-) mice). Compared to WT mice, Cpe(fat) mice exhibited AHR to aerosolized methacholine (measured using the forced oscillation technique) which was ablated in Cpe(fat)/TNFR2(-/-) mice. Bioplex or ELISA assay indicated significant increases in serum leptin, G-CSF, IL-7, IL-17A, TNFα, and KC in obese versus lean mice, as well as significant obesity-related increases in bronchoalveolar lavage fluid (BALF) G-CSF and IP-10, regardless of TNFR2 status. Importantly, BALF IL-17A was significantly increased over lean controls in Cpe(fat) but not Cpe(fat)/TNFR2(-/-) mice. Functional annotation clustering of significantly affected genes identified from microarray analysis comparing gene expression in lungs of Cpe(fat) and WT mice, identified blood vessel morphogenesis as the gene ontology category most affected by obesity. This category included several genes associated with AHR, including endothelin and trkB. Obesity increased pulmonary mRNA expression of endothelin and trkB in TNFR2 sufficient but not deficient mice. Our results indicate that TNFR2 signaling is required for the innate AHR that develops in obese mice, and suggest that TNFR2 may act by promoting IL-17A, endothelin, and/or trkB expression.
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17
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De Boer MP, Meijer RI, Wijnstok NJ, Jonk AM, Houben AJ, Stehouwer CD, Smulders YM, Eringa EC, Serné EH. Microvascular dysfunction: a potential mechanism in the pathogenesis of obesity-associated insulin resistance and hypertension. Microcirculation 2012; 19:5-18. [PMID: 21883642 DOI: 10.1111/j.1549-8719.2011.00130.x] [Citation(s) in RCA: 102] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The intertwined epidemics of obesity and related disorders such as hypertension, insulin resistance, type 2 diabetes, and subsequent cardiovascular disease pose a major public health challenge. To meet this challenge, we must understand the interplay between adipose tissue and the vasculature. Microvascular dysfunction is important not only in the development of obesity-related target-organ damage but also in the development of cardiovascular risk factors such as hypertension and insulin resistance. The present review examines the role of microvascular dysfunction as an explanation for the associations among obesity, hypertension, and impaired insulin-mediated glucose disposal. We also discuss communicative pathways from adipose tissue to the microcirculation.
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Affiliation(s)
- Michiel P De Boer
- Department of Internal Medicine, VU University Medical Center, Amsterdam, The Netherlands
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18
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Pernow J, Shemyakin A, Böhm F. New perspectives on endothelin-1 in atherosclerosis and diabetes mellitus. Life Sci 2012; 91:507-16. [PMID: 22483688 DOI: 10.1016/j.lfs.2012.03.029] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Revised: 02/20/2012] [Accepted: 03/12/2012] [Indexed: 11/26/2022]
Abstract
Endothelin-1 (ET-1) is a vasoconstrictor, proinflammatory and proliferative endothelial cell-derived peptide that is of significant importance in the regulation of vascular function. It is involved in the development of endothelial dysfunction including important interactions with nitric oxide. The expression and functional effects of ET-1 and its receptors are markedly altered during development of cardiovascular disease. Increased production of ET-1 and its receptors mediate many pathophysiological events contributing to the development of atherosclerosis and vascular complications in diabetes mellitus. The present review focuses on the pathophysiological role of ET-1 and the potential importance of ET receptors as a therapeutic target for treatment of these conditions.
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Affiliation(s)
- John Pernow
- Karolinska Institutet, Cardiology Unit, Department of Medicine, Karolinska University Hospital, 171 76 Stockholm, Sweden.
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Barton M, Baretella O, Meyer MR. Obesity and risk of vascular disease: importance of endothelium-dependent vasoconstriction. Br J Pharmacol 2012; 165:591-602. [PMID: 21557734 PMCID: PMC3315033 DOI: 10.1111/j.1476-5381.2011.01472.x] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2011] [Revised: 04/04/2011] [Accepted: 04/25/2011] [Indexed: 12/11/2022] Open
Abstract
UNLABELLED Obesity has become a serious global health issue affecting both adults and children. Recent devolopments in world demographics and declining health status of the world's population indicate that the prevalence of obesity will continue to increase in the next decades. As a disease, obesity has deleterious effects on metabolic homeostasis, and affects numerous organ systems including heart, kidney and the vascular system. Thus, obesity is now regarded as an independent risk factor for atherosclerosis-related diseases such as coronary artery disease, myocardial infarction and stroke. In the arterial system, endothelial cells are both the source and target of factors contributing to atherosclerosis. Endothelial vasoactive factors regulate vascular homeostasis under physiological conditions and maintain basal vascular tone. Obesity results in an imbalance between endothelium-derived vasoactive factors favouring vasoconstriction, cell growth and inflammatory activation. Abnormal regulation of these factors due to endothelial cell dysfunction is both a consequence and a cause of vascular disease processes. Finally, because of the similarities of the vascular pathomechanisms activated, obesity can be considered to cause accelerated, 'premature' vascular aging. Here, we will review some of the pathomechanisms involved in obesity-related activation of endothelium-dependent vasoconstriction, the clinical relevance of obesity-associated vascular risk, and therapeutic interventions using 'endothelial therapy' aiming at maintaining or restoring vascular endothelial health. LINKED ARTICLES This article is part of a themed section on Fat and Vascular Responsiveness. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.165.issue-3.
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Affiliation(s)
- Matthias Barton
- Molecular Internal Medicine, University of Zurich, Zurich, Switzerland.
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Vykoukal D, Davies MG. Vascular biology of metabolic syndrome. J Vasc Surg 2011; 54:819-31. [PMID: 21439758 PMCID: PMC3136643 DOI: 10.1016/j.jvs.2011.01.003] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2010] [Revised: 01/02/2011] [Accepted: 01/06/2011] [Indexed: 12/20/2022]
Abstract
The metabolic syndrome is a constellation of clinical risk factors comprising atherogenic dyslipidemia (low high-density lipoprotein and high triglycerides levels), elevated blood pressure, elevated plasma glucose, a prothrombotic state, and a proinflammatory state accompanied by an increased risk for cardiovascular disease and type 2 diabetes mellitus. The adipose tissue of obese humans contains increased numbers of macrophages, and once activated, these macrophages are responsible for the expression of most of the tissue's tumor necrosis factor (TNF)-α and interleukin (IL)-6. Chronic inflammation associated with visceral obesity induces altered lipoprotein metabolism and insulin resistance in the liver. Adipocytes secrete a variety of hormones, cytokines, growth factors, and other bioactive substances, conceptualized as adipocytokines, including plasminogen activator inhibitor 1 (PAI-1), TNF-α, leptin, and adiponectin. The dysregulation of these adipokines contributes to the pathogenesis of obesity. Adipose tissue-resident macrophages and adipocytes in the adipose tissue combined with the consequences of hyperglycemia, altered lipoproteins, and hyperinsulinemia in the vasculature and within organ microcirculation lead to dysfunctional endothelia and a proinflammatory state. Metabolic syndrome thus represents a combination of synergistic vascular pathologies that lead to an accelerated atherogenic state that compromises the ability of the patient to satisfactorily respond to humoral, cellular, and mechanical stresses.
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Affiliation(s)
- Daynene Vykoukal
- Vascular Biology and Therapeutics Program, The Methodist Hospital Research Institute, The Methodist Hospital, Houston, TX77030, USA
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Shemyakin A, Salehzadeh F, Esteves Duque-Guimaraes D, Böhm F, Rullman E, Gustafsson T, Pernow J, Krook A. Endothelin-1 reduces glucose uptake in human skeletal muscle in vivo and in vitro. Diabetes 2011; 60:2061-7. [PMID: 21677282 PMCID: PMC3142065 DOI: 10.2337/db10-1281] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
OBJECTIVE Endothelin (ET)-1 is a vasoconstrictor and proinflammatory peptide that may interfere with glucose uptake. Our objective was to investigate whether exogenous ET-1 affects glucose uptake in the forearm of individuals with insulin resistance and in cultured human skeletal muscle cells. RESEARCH DESIGN AND METHODS Nine male subjects (aged 61 ± 3 years) with insulin resistance (M value <5.5 mg/kg/min or a homeostasis model assessment of insulin resistance index >2.5) participated in a protocol using saline infusion followed by ET-1 infusion (20 pmol/min) for 2 h into the brachial artery. Forearm blood flow (FBF), endothelium-dependent vasodilatation, and endothelium-independent vasodilatation were assessed. Molecular signaling and glucose uptake were determined in cultured skeletal muscle cells. RESULTS ET-1 decreased forearm glucose uptake (FGU) by 39% (P < 0.05) after the 2-h infusion. ET-1 reduced basal FBF by 36% after the 2-h infusion (P < 0.05) and impaired both endothelium-dependent vasodilatation (P < 0.01) and endothelium-independent vasodilatation (P < 0.05). ET(A) and ET(B) receptor expression was detected on cultured skeletal muscle cells. One-hour ET-1 incubation increased glucose uptake in cells from healthy control subjects but not from type 2 diabetic patients. Incubation with ET-1 for 24 h reduced glucose uptake in cells from healthy subjects. ET-1 decreased insulin-stimulated Akt phosphorylation and increased phosphorylation of insulin receptor substrate-1 serine 636. CONCLUSIONS ET-1 not only induces vascular dysfunction but also acutely impairs FGU in individuals with insulin resistance and in skeletal muscle cells from type 2 diabetic subjects. These findings suggest that ET-1 may contribute to the development of insulin resistance in skeletal muscle in humans.
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Affiliation(s)
- Alexey Shemyakin
- Department of Medicine, Division of Cardiology, Karolinska Institute, Stockholm, Sweden.
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Alvarez Reyes F, Luna Gómez C, Brito Suárez M. Effect of the dual endothelin receptor antagonist bosentan on untreatable skin ulcers in a patient with diabetes: a case report. J Med Case Rep 2011; 5:151. [PMID: 21496286 PMCID: PMC3097146 DOI: 10.1186/1752-1947-5-151] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2010] [Accepted: 04/16/2011] [Indexed: 12/26/2022] Open
Abstract
Introduction Refractory skin ulcers are a major burden in patients with diabetes. Their pathogenesis is multifactorial, and data increasingly implicate endothelin as a mediator of diabetic macro- and microvasculopathy. Here we describe the first reported case of an endothelin receptor antagonist being used to successfully treat refractory skin ulcers in a patient with diabetes. Case presentation An 85-year-old Caucasian man with a 30-year history of type 2 diabetes developed multiple skin ulcerations, including a right heel ulcer. Despite appropriate treatment, the ulcer showed little improvement and the risk of amputation was high. The patient was treated with the dual endothelin receptor antagonist bosentan. After three weeks of treatment, major improvements were observed, and after 21 weeks, all ulcers had healed. No abnormalities were observed during monitoring of blood pressure, erythrocyte sedimentation rate or serum aminotransferase levels. Conclusion In patients with refractory ulceration associated with diabetes, bosentan may be of real benefit, especially in terms of amputation prevention. This case supports the proposed role for endothelin in the pathogenesis of skin ulceration in diabetes and is suggestive of a potential benefit of bosentan in this patient type. This case report is of interest to diabetologists and dermatologists.
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Affiliation(s)
- Fátima Alvarez Reyes
- Service of Rheumatology, Hospital Universitario Nuestra Señora de la Candelaria, ES-38010 Santa Cruz de Tenerife, Spain.
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Tesauro M, Canale MP, Rodia G, Di Daniele N, Lauro D, Scuteri A, Cardillo C. Metabolic syndrome, chronic kidney, and cardiovascular diseases: role of adipokines. Cardiol Res Pract 2011; 2011:653182. [PMID: 21403882 PMCID: PMC3051177 DOI: 10.4061/2011/653182] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2010] [Revised: 11/30/2010] [Accepted: 01/07/2011] [Indexed: 01/14/2023] Open
Abstract
Obesity is a chronic disease, whose incidence is alarmingly growing. It is associated with metabolic abnormalities and cardiovascular complications. These complications are clustered in the metabolic syndrome (MetS) leading to high cardiovascular morbidity and mortality. Obesity predisposes to diabetic nephropathy, hypertensive nephrosclerosis, and focal and segmental glomerular sclerosis and represents an independent risk factor for the development and progression of chronic kidney disease (CKD). Albuminuria is a major risk factor for cardiovascular diseases (CVDs). Microalbuminuria has been described as early manifestation of MetS-associated kidney damage and diabetic nephropathy. Obesity and MetS affect renal physiology and metabolism through mechanisms which include altered levels of adipokines such as leptin and adiponectin, oxidative stress, and inflammation. Secretory products of adipose tissue also deeply and negatively influence endothelial function. A better understanding of these interactions will help in designing more effective treatments aimed to protect both renal and cardiovascular systems.
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Affiliation(s)
- Manfredi Tesauro
- Department of Medicina Interna, Università di Tor Vergata, Viale Oxford 81, 00133 Rome, Italy
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Shemyakin A, Salehzadeh F, Böhm F, Al-Khalili L, Gonon A, Wagner H, Efendic S, Krook A, Pernow J. Regulation of glucose uptake by endothelin-1 in human skeletal muscle in vivo and in vitro. J Clin Endocrinol Metab 2010; 95:2359-66. [PMID: 20207830 DOI: 10.1210/jc.2009-1506] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
CONTEXT Expression of the vasoconstrictor and proinflammatory peptide endothelin (ET)-1 is increased in insulin-resistant (IR) subjects. OBJECTIVE The aim of this study was to investigate whether ET-1 regulates skeletal muscle glucose uptake in IR subjects in vivo and in cultured human skeletal muscle cells. DESIGN AND PARTICIPANTS Eleven subjects participated in three protocols using brachial artery infusion of: A) BQ123 (10 nmol/min) and BQ788 (10 nmol/min) (ET(A) and ET(B) receptor antagonist, respectively), followed by coinfusion with insulin (0.05 mU/kg/min); B) insulin alone; and C) insulin followed by coinfusion with ET-1 (20 pmol/min). MAIN OUTCOME MEASURES Forearm blood flow (FBF) and forearm glucose uptake (FGU) were determined. Glucose uptake and molecular signaling were determined in cultured skeletal muscle cells. RESULTS ET(A)/ET(B) receptor blockade increased FGU by 63% (P < 0.05). Coadministration of insulin caused a further 2-fold increase in FGU (P < 0.001). ET(A)/ET(B) receptor blockade combined with insulin resulted in greater FGU than insulin infusion alone (P < 0.005). ET(A)/ET(B) receptor blockade increased FBF by 30% (P < 0.05), with a further 16% increase (P < 0.01) during insulin coinfusion. ET-1 decreased basal FBF by 35% without affecting FGU. ET-1 impaired basal and insulin-stimulated glucose uptake in cultured muscle cells (P < 0.01) via an effect that was prevented by ET(A)/ET(B) receptor blockade. CONCLUSION ET(A)/ET(B) receptor blockade enhances basal and insulin-stimulated glucose uptake in IR subjects. ET-1 directly impairs glucose uptake in skeletal muscle cells via a receptor-dependent mechanism. These data suggest that ET-1 regulates glucose metabolism via receptor-dependent mechanisms in IR subjects.
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Affiliation(s)
- Alexey Shemyakin
- Karolinska University Hospital Solna, Center for Molecular Medicine, L8:03, S-171 76, Stockholm, Sweden.
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Jung C, Shemyakin A, Böhm F, Pernow J. Endothelial microparticles in patients with insulin resistance. DIABETES & METABOLISM 2009; 35:71-3. [DOI: 10.1016/j.diabet.2008.10.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2008] [Accepted: 10/27/2008] [Indexed: 10/21/2022]
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Lteif AA, Fulford AD, Considine RV, Gelfand I, Baron AD, Mather KJ. Hyperinsulinemia fails to augment ET-1 action in the skeletal muscle vascular bed in vivo in humans. Am J Physiol Endocrinol Metab 2008; 295:E1510-7. [PMID: 18957616 PMCID: PMC2603554 DOI: 10.1152/ajpendo.90549.2008] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Endogenous endothelin action is augmented in human obesity and type 2 diabetes and contributes to endothelial dysfunction and impairs insulin-mediated vasodilation in humans. We hypothesized that insulin resistance-associated hyperinsulinemia could preferentially drive endothelin-mediated vasoconstriction. We applied hyperinsulinemic-euglycemic clamps with higher insulin dosing in obese subjects than lean subjects (30 vs. 10 mU.m(-2).min(-1), respectively), with the goal of matching insulin's nitric oxide (NO)-mediated vascular effects. We predicted that, under these circumstances, insulin-stimulated endothelin-1 (ET-1) action (assessed with the type A endothelin receptor antagonist BQ-123) would be augmented in proportion to hyperinsulinemia. NO bioactivity was assessed using the nitric oxide synthase inhibitor N(G)-monomethyl-l-arginine. Insulin-mediated vasodilation and insulin-stimulated NO bioavailability were well matched across groups by this approach. As expected, steady-state insulin levels were approximately threefold higher in obese than lean subjects (109.2 +/- 10.2 pmol/l vs. 518.4 +/- 84.0, P = 0.03). Despite this, the augmentation of insulin-mediated vasodilation by BQ-123 was not different between groups. ET-1 flux across the leg was not augmented by insulin alone but was increased with the addition of BQ-123 to insulin (P = 0.01 BQ-123 effect, P = not significant comparing groups). Endothelin antagonism augmented insulin-stimulated NO bioavailability and NOx flux, but not differently between groups and not proportional to hyperinsulinemia. These findings do not support the hypothesis that insulin resistance-associated hyperinsulinemia preferentially drives endothelin-mediated vasoconstriction.
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Affiliation(s)
- Amale A Lteif
- Indiana Univ. School of Medicine, Indianapolis, IN 46202, USA
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Elgebaly MM, Kelly A, Harris AK, Elewa H, Portik-Dobos V, Ketsawatsomkron P, Marrero M, Ergul A. Impaired insulin-mediated vasorelaxation in a nonobese model of type 2 diabetes: role of endothelin-1. Can J Physiol Pharmacol 2008; 86:358-64. [PMID: 18516099 DOI: 10.1139/y08-034] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Insulin resistance involves decreased phosphorylation of insulin receptor substrate (IRS) proteins and (or) Akt. In the vasculature, modulated Akt phosphorylation may cause impaired vasorelaxation via decreased eNOS activation. Diet-induced insulin resistance enhances endothelin-1(ET-1)-mediated vasoconstriction and prevents vasodilatation to insulin. Presently, we evaluated insulin-mediated vascular relaxation, assessed molecular markers of the insulin signaling pathway, and determined the involvement of ET-1 in response to insulin by using selective ETA- or ETB-receptor blockade in a lean model of type 2 diabetes. Dose-response curves to insulin (0.01-100 ng/mL) were generated with wire myograph using thoracic aorta rings from control Wistar or diabetic Goto-Kakizaki (GK) rats (n=3-11). Maximal relaxation (Rmax) to insulin was significantly impaired and insulin sensitivity was decreased in the GK group. Preincubation with 1 micromol/L BQ-123 or BQ-788 for ETA- and ETB-receptor blockade, respectively, resulted in improved insulin sensitivity. Immunoblotting for native and phosphorylated Akt and IRS-1 revealed a decrease in Akt activation in the GK group. In vivo hyperinsulinemic euglycemic clamp studies showed decreased glucose utilization in GK rats, indicative of insulin resistance. These findings provide evidence that vascular insulin resistance occurs in a nonobese model of diabetes and that both ET receptor subtypes are involved in vascular relaxation to insulin.
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Affiliation(s)
- Mostafa M Elgebaly
- Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, Augusta, GA 30912, USA
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Muniyappa R, Iantorno M, Quon MJ. An integrated view of insulin resistance and endothelial dysfunction. Endocrinol Metab Clin North Am 2008; 37:685-711, ix-x. [PMID: 18775359 PMCID: PMC2613319 DOI: 10.1016/j.ecl.2008.06.001] [Citation(s) in RCA: 130] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Endothelial dysfunction and insulin resistance are frequently comorbid states. Vasodilator actions of insulin are mediated by phosphatidylinositol 3-kinase (PI3K)-dependent signaling pathways that stimulate production of nitric oxide from vascular endothelium. This helps to couple metabolic and hemodynamic homeostasis under healthy conditions. In pathologic states, shared causal factors, including glucotoxicity, lipotoxicity, and inflammation selectively impair PI3K-dependent insulin signaling pathways that contribute to reciprocal relationships between insulin resistance and endothelial dysfunction. This article discusses the implications of pathway-selective insulin resistance in vascular endothelium, interactions between endothelial dysfunction and insulin resistance, and therapeutic interventions that may simultaneously improve both metabolic and cardiovascular physiology in insulin-resistant conditions.
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Affiliation(s)
| | | | - Michael J. Quon
- Corresponding author for proof and reprints: Michael J. Quon, MD, PhD, Chief, Diabetes Unit, NCCAM, NIH, 9 Memorial Drive, Building 9, Room 1N-105 MSC 0920, Bethesda, MD 20892-0920, Tel: (301) 496-6269, Fax: (301) 402-1679,
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Raichlin E, Prasad A, Mathew V, Kent B, Holmes DR, Pumper GM, Nelson RE, Lerman LO, Lerman A. Efficacy and safety of atrasentan in patients with cardiovascular risk and early atherosclerosis. Hypertension 2008; 52:522-8. [PMID: 18695150 DOI: 10.1161/hypertensionaha.108.113068] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Endothelin plays an important role in the pathogenesis of atherosclerosis. The aim of the study was to evaluate the safety and hemodynamic and metabolic responses to 6 months treatment with atrasentan, the selective endothelin-A receptor antagonist. Seventy-two patients with multiple cardiovascular risk factors and nonobstructive coronary artery disease on coronary angiogram were randomly assigned in a double-blind manner to atrasentan or placebo. Mean aortic blood pressure decreased from 92+/-10 to 80+/-10 mm Hg (P<0.001) in the atrasentan group and did not change in the placebo group (93+/-10 and 92+/-11 mm Hg; P=0.84). The difference between the groups was significant (P<0.001). No effect on heart rate was observed. In a subgroup of patients not treated with angiotensin-converting enzyme inhibitor, creatinine level decreased in the atrasentan versus the placebo group (P=0.011). Fasting glucose (P=0.026), glycosylated hemoglobin level (P=0.041), triglyceride l (P=0.013), lipoprotein-A (P=0.046), and uric acid levels (P=0.048) decreased significantly in the atrasentan group compared with the placebo group. No progression of angiographic coronary disease was observed. The most common adverse effects with atrasentan were nasal stuffiness, headache, and edema. In conclusion, 6 months of treatment with atrasentan results in a reduction of blood pressure and improvement in glucose and lipid metabolism. These findings suggest the beneficial role of atrasentan in the treatment of hypertension and metabolic syndrome.
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Affiliation(s)
- Eugenia Raichlin
- Division of Cardiovascular Diseases, Center for Coronary Physiology and Imaging, Mayo Clinic, Rochester, MN 55905, USA
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Yoon N, Lteif AA, Han K, Mather KJ. Endothelin contributes differently to peripheral vascular tone and blood pressure in human obesity and diabetes. ACTA ACUST UNITED AC 2008; 2:182-91. [DOI: 10.1016/j.jash.2007.10.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2007] [Revised: 10/05/2007] [Accepted: 10/10/2007] [Indexed: 01/08/2023]
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van Harmelen V, Eriksson A, Aström G, Wåhlén K, Näslund E, Karpe F, Frayn K, Olsson T, Andersson J, Rydén M, Arner P. Vascular peptide endothelin-1 links fat accumulation with alterations of visceral adipocyte lipolysis. Diabetes 2008; 57:378-86. [PMID: 18025413 DOI: 10.2337/db07-0893] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVE Visceral obesity increases risk of insulin resistance and type 2 diabetes. This may partly be due to a region-specific resistance to insulin's antilipolytic effect in visceral adipocytes. We investigated whether adipose tissue releases the vascular peptide endothelin-1 (ET-1) and whether ET-1 could account for regional differences in lipolysis. RESEARCH DESIGN AND METHODS One group consisted of eleven obese and eleven nonobese subjects in whom ET-1 levels were compared between abdominal subcutaneous and arterialized blood samples. A second group included subjects undergoing anti-obesity surgery. Abdominal subcutaneous and visceral adipose tissues were obtained to study the effect of ET-1 on differentiated adipocytes regarding lipolysis and gene and protein expression. RESULTS Adipose tissue had a marked net release of ET-1 in vivo, which was 2.5-fold increased in obesity. In adipocytes treated with ET-1, the antilipolytic effect of insulin was attenuated in visceral but not in subcutaneous adipocytes, which could not be explained by effects of ET-1 on adipocyte differentiation. ET-1 decreased the expression of insulin receptor, insulin receptor substrate-1 and phosphodiesterase-3B and increased the expression of endothelin receptor-B (ET(B)R) in visceral but not in subcutaneous adipocytes. These effects were mediated via ET(B)R with signals through protein kinase C and calmodulin pathways. The effect of ET-1 could be mimicked by knockdown of IRS-1. CONCLUSIONS ET-1 is released from human adipose tissue and links fat accumulation to insulin resistance. It selectively counteracts insulin inhibition of visceral adipocyte lipolysis via ET(B)R signaling pathways, which affect multiple steps in insulin signaling.
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Affiliation(s)
- Vanessa van Harmelen
- Karolinska Institutet, Department of Medicine, M63, Karolinska University Hospital, Huddinge, SE-141 86 Stockholm, Sweden
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Lekli I, Szabo G, Juhasz B, Das S, Das M, Varga E, Szendrei L, Gesztelyi R, Varadi J, Bak I, Das DK, Tosaki A. Protective mechanisms of resveratrol against ischemia-reperfusion-induced damage in hearts obtained from Zucker obese rats: the role of GLUT-4 and endothelin. Am J Physiol Heart Circ Physiol 2007; 294:H859-66. [PMID: 18065527 DOI: 10.1152/ajpheart.01048.2007] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The resveratrol-induced cardiac protection was studied in Zucker obese rats. Rats were divided into five groups: group 1, lean control; group 2, obese control (OC); group 3, obese rats treated orally with 5 mg kg(-1) day(-1) of resveratrol (OR) for 2 wk; group 4, obese rats received 10% glucose solution ad libitum for 3 wk (OG); and group 5, obese rats received 10% glucose for 3 wk and resveratrol (OGR) during the 2nd and 3rd wk. Body weight, serum glucose, and insulin were measured, and then hearts were isolated and subjected to 30 min of ischemia followed by 120 min of reperfusion. Heart rate, coronary flow, aortic flow, developed pressure, the incidence of reperfusion-induced ventricular fibrillation, and infarct size were measured. Resveratrol reduced body weight and serum glucose in the OR compared with the OC values (414 +/- 10 g and 7.08 +/- 0.41 mmol/l, respectively, to 378 +/- 12 g and 6.11 +/- 0.44 mmol/l), but insulin levels were unchanged. The same results were obtained for the OG vs. OGR group. Resveratrol improved postischemic cardiac function in the presence or absence of glucose intake compared with the resveratrol-free group. The incidence of ventricular fibrillation and infarct size was reduced by 83 and 20% in the OR group, and 67 and 16% in the OGR group, compared with the OC and OG groups, respectively. Resveratrol increased GLUT-4 expression and reduced endothelin expression and cardiac apoptosis in ischemic-reperfused hearts in the presence or absence of glucose intake. Thus the protective effect of resveratrol could be related to its direct effects on the heart.
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Affiliation(s)
- Istvan Lekli
- Department of Pharmacology, Faculty of Pharmacy, Health Science Center, University of Debrecen, Debrecen, Hungary
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Magnifying endoscopic observation of the gastric mucosa, particularly in patients with atrophic gastritis. Endoscopy 1979. [PMID: 738222 DOI: 10.1007/s00380-009-1178-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2024]
Abstract
The gastric mucosal surface was observed using the magnifying fibergastroscope (FGS-ML), and the fine gastric mucosal patterns, which were even smaller than one unit of gastric area, were examined at a magnification of about 30. For simplicification, we classified these patterns by magnifying endoscopy in the following ways; FP, FIP, FSP, SP and MP, modifying Yoshii's classification under the dissecting microscope. The FIP, which was found to have round and long elliptical gastric pits, is a new addition to our endoscopic classification. The relationship between the FIP and the intermediate zone was evaluated by superficial and histological studies of surgical and biopsy specimens. The width of the band of FIP seems to be related to the severity of atrophic gastritis. Also, the transformation of FP to FIP was assessed by comparing specimens taken from the resected and residual parts of the stomach, respectively. Moreover, it appears that severe gastritis occurs in the gastric mucosa which shows a FIP. Therefore, we consider that the FIP indicates the position of the atrophic border.
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