1
|
Pan H, Xiong Y, Huang Y, Zhao J, Wan H. Association between stress hyperglycemia ratio with short-term and long-term mortality in critically ill patients with ischemic stroke. Acta Diabetol 2024; 61:859-868. [PMID: 38499778 DOI: 10.1007/s00592-024-02259-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Accepted: 02/11/2024] [Indexed: 03/20/2024]
Abstract
AIMS Hyperglycemia on admission is associated with poor prognosis in ischemic stroke (IS) patients. We aimed to investigate the relationship between stress hyperglycemia ratio (SHR) and short-term or long-term mortality in IS patients in the ICU and to explore whether this relationship is influenced by diabetes status. MATERIALS AND METHODS We collected patients with severe IS requiring ICU admission in the Medical Information Mart for Intensive Care (MIMIC-IV) database and calculated SHR. Outcomes included 30-day, 90-day, and 1-year mortality. The association between SHR and mortality in patients with critical IS was elucidated using Multivariate Cox regression and subgroup analysis for diabetes. RESULTS A total of 1376 patients were recruited. After adjusting for potential confounders, patients in the third and fourth quartiles had a significantly increased risk of death at 30 days, 90 days, and 1 year compared to the first quartile of SHR (Q3 vs. Q1: HR 1.56-1.80, all p < 0.02; Q4 vs. Q1: HR 1.75-2.15, all p < 0.001; all p for trend < 0.001). In addition, the highest quartile of SHR was significantly associated with short-term or long-term mortality compared with the first quartile, regardless of diabetes status. CONCLUSIONS Our results suggest that stress hyperglycemia, defined by the glucose/HbA1c ratio, is associated with increased short-term and long-term mortality in patients with ischemic stroke, independent of the patient's diabetes status.
Collapse
Affiliation(s)
- Haowei Pan
- Second School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Yiqun Xiong
- Second School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Yanming Huang
- Second School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
- Department of Anesthesiology, Hangzhou Red Cross Hospital, 208 East Huancheng Road, Hangzhou, 310003, China
| | - Jie Zhao
- Department of Anesthesiology, Hangzhou Red Cross Hospital, 208 East Huancheng Road, Hangzhou, 310003, China
| | - Haifang Wan
- Department of Anesthesiology, Hangzhou Red Cross Hospital, 208 East Huancheng Road, Hangzhou, 310003, China.
| |
Collapse
|
2
|
Ushakov A, Ivanchenko V, Gagarina A. Heart Failure And Type 2 Diabetes Mellitus: Neurohumoral, Histological And Molecular Interconnections. Curr Cardiol Rev 2023; 19:e170622206132. [PMID: 35718961 PMCID: PMC10201898 DOI: 10.2174/1573403x18666220617121144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 04/27/2022] [Accepted: 05/04/2022] [Indexed: 11/22/2022] Open
Abstract
Heart failure (HF) is a global healthcare burden and a leading cause of morbidity and mortality worldwide. Type 2 diabetes mellitus (T2DM) appears to be one of the major risk factors that significantly worsen HF prognosis and increase the risk of fatal cardiovascular outcomes. Despite a great knowledge of pathophysiological mechanisms involved in HF development and progression, hospitalization rates in patients with HF and concomitant T2DM remain elevated. In this review, we discuss the complex interplay between systemic neurohumoral regulation and local cardiac mechanisms participating in myocardial remodeling and HF development in T2DM with special attention to cardiomyocyte energy metabolism, mitochondrial function and calcium metabolism, cardiomyocyte hypertrophy and death, extracellular matrix remodeling.
Collapse
Affiliation(s)
- A. Ushakov
- Department of Internal Medicine 1, Medical Academy named after S.I. Georgievsky of V.I. Vernadsky Crimean Federal University, Simferopol, Russian Federation
| | - V. Ivanchenko
- Department of Internal Medicine 1, Medical Academy named after S.I. Georgievsky of V.I. Vernadsky Crimean Federal University, Simferopol, Russian Federation
| | - A. Gagarina
- Department of Internal Medicine 1, Medical Academy named after S.I. Georgievsky of V.I. Vernadsky Crimean Federal University, Simferopol, Russian Federation
| |
Collapse
|
3
|
Yao M, Hao Y, Wang T, Xie M, Li H, Feng J, Feng L, Ma D. A review of stress-induced hyperglycaemia in the context of acute ischaemic stroke: Definition, underlying mechanisms, and the status of insulin therapy. Front Neurol 2023; 14:1149671. [PMID: 37025208 PMCID: PMC10070880 DOI: 10.3389/fneur.2023.1149671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2023] [Accepted: 02/21/2023] [Indexed: 04/08/2023] Open
Abstract
The transient elevation of blood glucose produced following acute ischaemic stroke (AIS) has been described as stress-induced hyperglycaemia (SIH). SIH is common even in patients with AIS who have no previous diagnosis of diabetes mellitus. Elevated blood glucose levels during admission and hospitalization are strongly associated with enlarged infarct size and adverse prognosis in AIS patients. However, insulin-intensive glucose control therapy defined by admission blood glucose for SIH has not achieved the desired results, and new treatment ideas are urgently required. First, we explore the various definitions of SIH in the context of AIS and their predictive value in adverse outcomes. Then, we briefly discuss the mechanisms by which SIH arises, describing the dual effects of elevated glucose levels on the central nervous system. Finally, although preclinical studies support lowering blood glucose levels using insulin, the clinical outcomes of intensive glucose control are not promising. We discuss the reasons for this phenomenon.
Collapse
Affiliation(s)
- Mengyue Yao
- Department of Neurology and Neuroscience Centre, The First Hospital of Jilin University, Changchun, Jilin, China
| | - Yulei Hao
- Department of Neurology and Neuroscience Centre, The First Hospital of Jilin University, Changchun, Jilin, China
| | - Tian Wang
- Department of Neurology and Neuroscience Centre, The First Hospital of Jilin University, Changchun, Jilin, China
| | - Meizhen Xie
- Department of Neurology and Neuroscience Centre, The First Hospital of Jilin University, Changchun, Jilin, China
| | - Hui Li
- Department of Neurology and Neuroscience Centre, The First Hospital of Jilin University, Changchun, Jilin, China
| | - Jiachun Feng
- Department of Neurology and Neuroscience Centre, The First Hospital of Jilin University, Changchun, Jilin, China
| | - Liangshu Feng
- Stroke Centre, Department of Neurology, The First Hospital of Jilin University, Changchun, Jilin, China
- Liangshu Feng
| | - Di Ma
- Department of Neurology and Neuroscience Centre, The First Hospital of Jilin University, Changchun, Jilin, China
- *Correspondence: Di Ma
| |
Collapse
|
4
|
Wang X, Song T, Sun Y, Men L, Gu Y, Zhang S, Chen X. Proteomic Analysis Reveals the Effect of Trichostatin A and Bone Marrow-Derived Dendritic Cells on the Fatty Acid Metabolism of NIH3T3 Cells under Oxygen-Glucose Deprivation Conditions. J Proteome Res 2020; 20:960-971. [PMID: 33226813 DOI: 10.1021/acs.jproteome.0c00713] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Fibroblasts mediate acute wound healing and long-term tissue remodeling with scarring after tissue injury. Following myocardial infarction (MI), necrotized cardiomyocytes become replaced by secreted extracellular matrix proteins produced by fibroblasts. Dendritic cells (DCs) can migrate from the bone marrow to the infarct areas and infarct border areas to mediate collagen accumulation after MI. Trichostatin A (TSA) is known to regulate apoptosis and proliferation in fibroblasts and affect the functions of DCs under oxygen-glucose deprivation (OGD) conditions. In this study, we used label-free quantitative proteomics to investigate the effects of TSA and bone marrow-derived dendritic cells (BMDCs) on NIH3T3 fibroblasts under OGD conditions. The results showed that the fatty acid degradation pathway was significantly upregulated in NIH3T3 cells under OGD conditions and that the fatty acid synthesis pathway was significantly downregulated in NIH3T3 cells treated with conditioned media (CM) from BMDCs treated with TSA under OGD conditions [BMDCs-CM(TSA)]. In addition, BMDCs-CM(TSA) significantly decreased the levels of triglycerides and free fatty acids and mediated fatty acid metabolism-related proteins in NIH3T3 cells under OGD conditions. In summary, this proteomics analysis showed that TSA and BMDCs affect fatty acid metabolism in NIH3T3 cells under OGD conditions.
Collapse
Affiliation(s)
- Xuan Wang
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun 130000, China
| | - Tongtong Song
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun 130000, China
| | - Yunpeng Sun
- Cardiac Surgery Department, The First Hospital of Jilin University, Changchun 130000, China
| | - Lihui Men
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun 130000, China
| | - Yiwen Gu
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun 130000, China
| | - Siwei Zhang
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun 130000, China
| | - Xia Chen
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun 130000, China
| |
Collapse
|
5
|
Commentary: Hyperglycemia during myocardial infarction: Can sound waves improve outcomes? J Thorac Cardiovasc Surg 2019; 161:e307-e308. [PMID: 31757457 DOI: 10.1016/j.jtcvs.2019.10.094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 10/18/2019] [Accepted: 10/18/2019] [Indexed: 11/22/2022]
|
6
|
Hafez P, Chowdhury SR, Jose S, Law JX, Ruszymah BHI, Mohd Ramzisham AR, Ng MH. Development of an In Vitro Cardiac Ischemic Model Using Primary Human Cardiomyocytes. Cardiovasc Eng Technol 2018; 9:529-538. [PMID: 29948837 DOI: 10.1007/s13239-018-0368-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Accepted: 05/26/2018] [Indexed: 12/17/2022]
Abstract
Developing experimental models to study ischemic heart disease is necessary for understanding of biological mechanisms to improve the therapeutic approaches for restoring cardiomyocytes function following injury. The aim of this study was to develop an in vitro hypoxic/re-oxygenation model of ischemia using primary human cardiomyocytes (HCM) and define subsequent cytotoxic effects. HCM were cultured in serum and glucose free medium in hypoxic condition with 1% O2 ranging from 30 min to 12 h. The optimal hypoxic exposure time was determined using Hypoxia Inducible Factor 1α (HIF-1α) as the hypoxic marker. Subsequently, the cells were moved to normoxic condition for 3, 6 and 9 h to replicate the re-oxygenation phase. Optimal period of hypoxic/re-oxygenation was determined based on 50% mitochondrial injury via 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide assay and cytotoxicity via lactate dehydrogenase (LDH) assay. It was found that the number of cells expressing HIF-1α increased with hypoxic time and 3 h was sufficient to stimulate the expression of this marker in all the cells. Upon re-oxygenation, mitochondrial activity reduced significantly whereas the cytotoxicity increased significantly with time. Six hours of re-oxygenation was optimal to induce reversible cell injury. The injury became irreversible after 9 h as indicated by > 60% LDH leakage compared to the control group cultured in normal condition. Under optimized hypoxic reoxygenation experimental conditions, mesenchymal stem cells formed nanotube with ischemic HCM and facilitated transfer of mitochondria suggesting the feasibility of using this as a model system to study molecular mechanisms of myocardial injury and rescue.
Collapse
Affiliation(s)
- Pezhman Hafez
- Tissue Engineering Centre, Universiti Kebangsaan Malaysia Medical Centre, Jalan Yaacob Latif, Bandar Tun Razak, 56000, Kuala Lumpur, Malaysia
| | - Shiplu R Chowdhury
- Tissue Engineering Centre, Universiti Kebangsaan Malaysia Medical Centre, Jalan Yaacob Latif, Bandar Tun Razak, 56000, Kuala Lumpur, Malaysia
| | - Shinsmon Jose
- Division of Infectious Diseases, Department of Internal Medicine, University of Cincinnati, Cincinnati, OH, 45267, USA
| | - Jia Xian Law
- Tissue Engineering Centre, Universiti Kebangsaan Malaysia Medical Centre, Jalan Yaacob Latif, Bandar Tun Razak, 56000, Kuala Lumpur, Malaysia
| | - B H I Ruszymah
- Department of Physiology, Faculty of Medicine, Universiti Kebangsaan Malaysia, 56000, Kuala Lumpur, Malaysia
| | - Abdul Rahman Mohd Ramzisham
- Division of Cardiothoracic Surgery, Department of Surgery, Universiti Kebangsaan Malaysia Medical Centre, 56000, Kuala Lumpur, Malaysia
| | - Min Hwei Ng
- Tissue Engineering Centre, Universiti Kebangsaan Malaysia Medical Centre, Jalan Yaacob Latif, Bandar Tun Razak, 56000, Kuala Lumpur, Malaysia.
| |
Collapse
|
7
|
Russell J, Du Toit EF, Peart JN, Patel HH, Headrick JP. Myocyte membrane and microdomain modifications in diabetes: determinants of ischemic tolerance and cardioprotection. Cardiovasc Diabetol 2017; 16:155. [PMID: 29202762 PMCID: PMC5716308 DOI: 10.1186/s12933-017-0638-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 11/22/2017] [Indexed: 02/06/2023] Open
Abstract
Cardiovascular disease, predominantly ischemic heart disease (IHD), is the leading cause of death in diabetes mellitus (DM). In addition to eliciting cardiomyopathy, DM induces a ‘wicked triumvirate’: (i) increasing the risk and incidence of IHD and myocardial ischemia; (ii) decreasing myocardial tolerance to ischemia–reperfusion (I–R) injury; and (iii) inhibiting or eliminating responses to cardioprotective stimuli. Changes in ischemic tolerance and cardioprotective signaling may contribute to substantially higher mortality and morbidity following ischemic insult in DM patients. Among the diverse mechanisms implicated in diabetic impairment of ischemic tolerance and cardioprotection, changes in sarcolemmal makeup may play an overarching role and are considered in detail in the current review. Observations predominantly in animal models reveal DM-dependent changes in membrane lipid composition (cholesterol and triglyceride accumulation, fatty acid saturation vs. reduced desaturation, phospholipid remodeling) that contribute to modulation of caveolar domains, gap junctions and T-tubules. These modifications influence sarcolemmal biophysical properties, receptor and phospholipid signaling, ion channel and transporter functions, contributing to contractile and electrophysiological dysfunction, cardiomyopathy, ischemic intolerance and suppression of protective signaling. A better understanding of these sarcolemmal abnormalities in types I and II DM (T1DM, T2DM) can inform approaches to limiting cardiomyopathy, associated IHD and their consequences. Key knowledge gaps include details of sarcolemmal changes in models of T2DM, temporal patterns of lipid, microdomain and T-tubule changes during disease development, and the precise impacts of these diverse sarcolemmal modifications. Importantly, exercise, dietary, pharmacological and gene approaches have potential for improving sarcolemmal makeup, and thus myocyte function and stress-resistance in this ubiquitous metabolic disorder.
Collapse
Affiliation(s)
- Jake Russell
- Menzies Health Institute Queensland, Griffith University, Southport, QLD, Australia
| | - Eugene F Du Toit
- Menzies Health Institute Queensland, Griffith University, Southport, QLD, Australia
| | - Jason N Peart
- Menzies Health Institute Queensland, Griffith University, Southport, QLD, Australia
| | - Hemal H Patel
- VA San Diego Healthcare System and Department of Anesthesiology, University of California San Diego, San Diego, USA
| | - John P Headrick
- Menzies Health Institute Queensland, Griffith University, Southport, QLD, Australia. .,School of Medical Science, Griffith University, Southport, QLD, 4217, Australia.
| |
Collapse
|
8
|
胡 静, 谷 小, 孟 炎, 王 娅, 高 琴, 李 正, 李 晓, 程 向. [Effect of dexmedetomidine postconditioning on myocardial ischemia-reperfusion injury and inflammatory response in diabetic rats]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2017; 37:1506-1511. [PMID: 29180332 PMCID: PMC6779648 DOI: 10.3969/j.issn.1673-4254.2017.11.13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Indexed: 06/07/2023]
Abstract
OBJECTIVE To investigate the effect of dexmedetomidine postconditioning in alleviating myocardial ischemia-reperfusion (IR) injury and inflammation in diabetic mellitus rats. METHODS Thirty normal male Sprauge Dawley (SD) rats were randomly allocated into 3 groups (n=10), namely the sham-operated group, IR group, and dexmedetomidine postconditioning (DP) group. Similarly, another thirty diabetic SD rats were also randomly allocated into diabetic sham (DM-S) group, diabetic IR (DM-IR) group and diabetic dexmedetomidine postconditioning (DM-DP) group. The mean arterial pressure (MAP), heart rate (HR) and the rate pressure product (RPP) were recorded at baseline, after 30 min of ischemia, and at 30 and 120 min during reperfusion. Myocardial infarct size was analyzed by TTC double staining method, and plasma levels of CTnI, TNF-a, IL-6, IL-10 and IL-1β were measured at 120 min of reperfusion. RESULTS Compared with those in the sham-operated group, normal and diabetic rats in IR and DP groups showed significantly lowered MAP, HR, and RPP and increased levels of plasma CTnI, TNF-a, IL-6, IL-10 and IL-1β levels after 30 min of ischemia and at 30 min and 120 min of reperfusion (P<0.05). Compared with those in the IR group, the normal rats in DP group showed decreased MAP, HR, and RPP at 30 min of ischemia and at 30 min of reperfusion, which increased at 120 min of reperfusion (P<0.05); the infarct size and plasma CTnI, TNF-a, IL-6 and IL-1β levels were decreased while IL-10 was increased in DP group (P<0.05). Compared with those in DP group, the rats in DM-DP group showed similar MAP, HR and RPP (P>0.05) but significantly increased infarct size and plasma CTnI, TNF-a, IL-6 and IL-1β levels (P<0.05). CONCLUSION Dexmedetomidine postconditioning may produce a cardioprotective effect against myocardial IR injury in normal rats by alleviating inflammation, but can not reduce the release of inflammatory mediators in diabetic rats to improve myocardial infarction.
Collapse
Affiliation(s)
- 静 胡
- 蚌埠医学院第一附属医院麻醉科,安徽 蚌埠 233004Deparment of Anesthesiology, First Affiliated Hospital of Bengbu Medical College, Bengbu 233004, China
- 蚌埠医学院生理教研室,安徽 蚌埠 233030Department of Physiology, Bengbu Medical College, Bengbu 233030, China
| | - 小雨 谷
- 蚌埠医学院第一附属医院麻醉科,安徽 蚌埠 233004Deparment of Anesthesiology, First Affiliated Hospital of Bengbu Medical College, Bengbu 233004, China
- 蚌埠医学院生理教研室,安徽 蚌埠 233030Department of Physiology, Bengbu Medical College, Bengbu 233030, China
| | - 炎 孟
- 蚌埠医学院第一附属医院麻醉科,安徽 蚌埠 233004Deparment of Anesthesiology, First Affiliated Hospital of Bengbu Medical College, Bengbu 233004, China
| | - 娅 王
- 蚌埠医学院生理教研室,安徽 蚌埠 233030Department of Physiology, Bengbu Medical College, Bengbu 233030, China
| | - 琴 高
- 蚌埠医学院生理教研室,安徽 蚌埠 233030Department of Physiology, Bengbu Medical College, Bengbu 233030, China
| | - 正红 李
- 蚌埠医学院生理教研室,安徽 蚌埠 233030Department of Physiology, Bengbu Medical College, Bengbu 233030, China
| | - 晓红 李
- 蚌埠医学院第一附属医院麻醉科,安徽 蚌埠 233004Deparment of Anesthesiology, First Affiliated Hospital of Bengbu Medical College, Bengbu 233004, China
| | - 向阳 程
- 蚌埠医学院第一附属医院麻醉科,安徽 蚌埠 233004Deparment of Anesthesiology, First Affiliated Hospital of Bengbu Medical College, Bengbu 233004, China
| |
Collapse
|
9
|
Mitochondria as a target of cardioprotection in models of preconditioning. J Bioenerg Biomembr 2017; 49:357-368. [PMID: 28730272 DOI: 10.1007/s10863-017-9720-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 06/14/2017] [Indexed: 12/24/2022]
Abstract
Over the recent years the view on mitochondria in the heart as a cellular powerhouse providing ATP supply needed to sustain contractile function, basal metabolic processes, and ionic homeostasis has changed radically. At present it is known that dysfunctions of these organelles are essential in the development of a large number of diseases, including cardiovascular diseases. Moreover, mitochondria are considered to be a very promising target of endogenous strategies that are essential in the protection of the myocardium from acute ischemia/reperfusion injury. These strategies including ischemic preconditioning, remote ischemic preconditioning as well as the acute phase of streptozotocin-induced diabetes mellitus, provide a similar effect of protection. Alterations observed in the functional and structural properties of heart mitochondria caused by short-term pathological impulses are associated with endogenous cardioprotective processes. It seems that the extent of mitochondrial membrane fluidization could be an active response mechanism to injury with a subtle effect on membrane-associated processes which further affect the environment of the whole organelle, thus inducing metabolic changes in the heart. In this review article, we provide an overview of endogenous protective mechanisms induced by hypoxic, pseudohypoxic and ischemic conditions with special consideration of the role of heart mitochondria in these processes.
Collapse
|
10
|
Arrhythmia Vulnerability in Diabetic Cardiac Tissue is Species-Dependent: Effects of I KATP, Uncoupling, and Connexin Lateralization. Cardiovasc Eng Technol 2017; 8:527-538. [PMID: 28656565 DOI: 10.1007/s13239-017-0315-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 06/22/2017] [Indexed: 10/19/2022]
Abstract
Amongst the complications of diabetes is arrhythmia, the risk of which depends on multiple factors. This study was designed to investigate several factors, including the effects of ATP-sensitive potassium current, lateralized connexins, and gap junction uncoupling. ATP-sensitive potassium channel (I KATP) opening is caused by ischemia, which can occur in diabetic or non-diabetic hearts. I KATP opening was simulated in this work to determine if the risk of ischemia-induced arrhythmias is affected by diabetes. Simulations were performed using healthy and diabetic models of rat and rabbit ventricle. Results showed that the diabetic rat model is less vulnerable to reentrant arrhythmia than the healthy rat model. The diabetic rabbit model was more vulnerable to reentrant arrhythmia than the healthy rabbit model. In both rabbit models, the vulnerability increased as the gap junctional coupling decreased. Opening of I KATP resulted in larger window of vulnerability. Conduction reserve was simulated based on 1D simulations for both rat and rabbit models. There was no difference between rat and rabbit conduction reserve. Our results showed that the simulation results are model-dependent, i.e., results from the rabbit model are similar to human clinical data, while the results from the rat model contradict human clinical observations, suggesting a significant species-dependence in arrhythmia vulnerability in the diabetic heart.
Collapse
|
11
|
Malfitano C, de Souza Junior AL, Carbonaro M, Bolsoni-Lopes A, Figueroa D, de Souza LE, Silva KAS, Consolim-Colombo F, Curi R, Irigoyen MC. Glucose and fatty acid metabolism in infarcted heart from streptozotocin-induced diabetic rats after 2 weeks of tissue remodeling. Cardiovasc Diabetol 2015; 14:149. [PMID: 26553117 PMCID: PMC4640361 DOI: 10.1186/s12933-015-0308-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 10/23/2015] [Indexed: 01/24/2023] Open
Abstract
Background The effects of streptozotocin (STZ)-induced diabetes on heart metabolism and function after myocardial infarction (MI) remodelling were investigated in rats. Methods Fifteen days after STZ (50 mg/kg b.w. i.v.) injection, MI was induced by surgical occlusion of the left coronary artery. Two weeks after MI induction, contents of glycogen, ATP, free fatty acids and triacylglycerols (TG) and enzyme activities of glycolysis and Krebs cycle (hexokinase, glucose-6-phosphate dehydrogenase, phosphofructokinase, citrate synthase) and expression of carnitine palmitoyl-CoA transferase I (a key enzyme of mitochondrial fatty acid oxidation) were measured in the left ventricle (LV). Plasma glucose, free fatty acids and triacylglycerol levels were determined. Ejection fraction (EF) and shortening fraction (SF) were also measured by echocardiography. Results Glycogen and TG contents were increased (p < 0.05) whereas ATP content was decreased in the LV of the non-infarcted diabetic group when compared to the control group (p < 0.05). When compared to infarcted control rats (MI), the diabetic infarcted rats (DI) showed (p < 0.05): increased plasma glucose and TG levels, elevated free fatty acid levels and increased activity of, citrate synthase and decreased ATP levels in the LV. Infarct size was smaller in the DI group when compared to MI rats (p < 0.05), and this was associated with higher EF and SF (p < 0.05). Conclusions Systolic function was preserved or recovered more efficiently in the heart from diabetic rats two weeks after MI, possibly due to the high provision of glucose and free fatty acids from both plasma and heart glycogen and triacylglycerol stores.
Collapse
Affiliation(s)
- Christiane Malfitano
- Hypertension Unit, Heart Institute (InCor), Medical School of University of São Paulo, Av. Eneas de Carvalho Aguiar, 44, 05403-000, Sao Paulo, SP, Brazil. .,Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil.
| | - Alcione Lescano de Souza Junior
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil. .,Nursing Department, State University of Mato Grosso, Alta Floresta, Brazil.
| | - Mariana Carbonaro
- Hypertension Unit, Heart Institute (InCor), Medical School of University of São Paulo, Av. Eneas de Carvalho Aguiar, 44, 05403-000, Sao Paulo, SP, Brazil.
| | - Andressa Bolsoni-Lopes
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil.
| | - Diego Figueroa
- Hypertension Unit, Heart Institute (InCor), Medical School of University of São Paulo, Av. Eneas de Carvalho Aguiar, 44, 05403-000, Sao Paulo, SP, Brazil.
| | - Leandro Ezequiel de Souza
- Hypertension Unit, Heart Institute (InCor), Medical School of University of São Paulo, Av. Eneas de Carvalho Aguiar, 44, 05403-000, Sao Paulo, SP, Brazil.
| | | | - Fernanda Consolim-Colombo
- Hypertension Unit, Heart Institute (InCor), Medical School of University of São Paulo, Av. Eneas de Carvalho Aguiar, 44, 05403-000, Sao Paulo, SP, Brazil. .,Laboratory of Translational Physiology, Universidade Nove de Julho, (UNINOVE), Sao Paulo, Brazil.
| | - Rui Curi
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil.
| | - Maria Claudia Irigoyen
- Hypertension Unit, Heart Institute (InCor), Medical School of University of São Paulo, Av. Eneas de Carvalho Aguiar, 44, 05403-000, Sao Paulo, SP, Brazil. .,Laboratory of Translational Physiology, Universidade Nove de Julho, (UNINOVE), Sao Paulo, Brazil.
| |
Collapse
|
12
|
Malfitano C, Barboza CA, Mostarda C, da Palma RK, dos Santos CP, Rodrigues B, Freitas SCF, Belló-Klein A, Llesuy S, Irigoyen MC, De Angelis K. Diabetic hyperglycemia attenuates sympathetic dysfunction and oxidative stress after myocardial infarction in rats. Cardiovasc Diabetol 2014; 13:131. [PMID: 25301475 PMCID: PMC4198704 DOI: 10.1186/s12933-014-0131-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Accepted: 08/29/2014] [Indexed: 12/29/2022] Open
Abstract
Background Previous research has demonstrated that hyperglycemia may protect the heart against ischemic injury. The aim of the present study was to investigate the association between hyperglycemia and myocardial infarction on cardiovascular autonomic modulation and cardiac oxidative stress profile in rats. Male Wistar rats were divided into: control (C), diabetic (D), myocardial infarcted (MI) and diabetic infarcted rats (DMI). Methods Diabetes was induced by streptozotocin (STZ, 50 mg/Kg) at the beginning of the protocol and MI was induced by left coronary occlusion 15 days after STZ. Thirty days after streptozocin-induced diabetes, cardiovascular autonomic modulation was evaluated by spectral analysis, and oxidative stress profile was determined by antioxidant enzyme activities and superoxide anion, together with protein carbonylation and redox balance of glutathione (GSH/GSSG). Results The diabetic and infarcted groups showed decreased heart rate variability and vagal modulation (p < 0.05); however, sympathetic modulation decreased only in diabetic groups (p < 0.05). Sympatho/vagal balance and vascular sympathetic modulation were increased only in the MI group (p < 0.05). Diabetes promoted an increase in catalase concentration (p < 0.05). Glutathione peroxidase activity was increased only in DMI when compared to the other groups (p < 0.05). Superoxide anion and protein carbonylation were increased only in MI group (p < 0.05). Cardiac redox balance, as evaluated by GSH/GSSG, was lower in the MI group (p < 0.05). Conclusions These data suggest that hyperglycemia promotes compensatory mechanisms that may offer protection against ischemia, as demonstrated by increased antioxidants, decreased pro-oxidants and protein damage, possibly related to the improvements in both redox balance and sympathetic modulation to the heart.
Collapse
|
13
|
Malfitano C, de Souza Junior AL, Irigoyen MC. Impact of conditioning hyperglycemic on myocardial infarction rats: Cardiac cell survival factors. World J Cardiol 2014; 6:449-454. [PMID: 24976917 PMCID: PMC4072835 DOI: 10.4330/wjc.v6.i6.449] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2013] [Revised: 03/14/2014] [Accepted: 04/19/2014] [Indexed: 02/06/2023] Open
Abstract
While clinical data have suggested that the diabetic heart is more susceptible to ischemic heart disease (IHD), animal data have so far pointed to a lower probability of IHD. Thus, the aim of this present review is to look at these conflicting results and discuss the protective mechanisms that conditioned hyperglycemia may confer to the heart against ischemic injury. Several mechanisms have been proposed to explain the cardioprotective action of high glucose exposure, namely, up-regulation of anti-apoptotic factor Bcl-2, inactivation of pro-apoptotic factor bad, and activation of pro-survival factors such as protein kinase B (Akt), vascular endothelial growth factor (VEGF), hypoxia inducible factor-1α and protein kinase C-ε. Indeed, cytosolic increase in Ca2+ concentration, the mitochondrial permeability transition pore, plays a key role in the genesis of ischemic injury. Previous studies have shown that the diabetic heart decreased Na+/Ca2+ and Na+/H+ exchanger activity and as such it accumulates less Ca2+ in cardiomyocyte, thus preventing cardiac injury and the associated heart dysfunctions. In addition, the expression of VEGF in diabetic animals leads to increased capillary density before myocardial infarction. Despite poor prognostic in the long-term, all these results suggest that diabetes mellitus and consequently hyperglycemia may indeed play a cardioprotective role against myocardial infarction in the short term.
Collapse
|
14
|
Luo G, Liu H, Luo S, Li F, Su M, Lu H. Fasting hyperglycemia increases in-hospital mortality risk in nondiabetic female patients with acute myocardial infarction: a retrospective study. Int J Endocrinol 2014; 2014:745093. [PMID: 25132854 PMCID: PMC4123565 DOI: 10.1155/2014/745093] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Revised: 06/14/2014] [Accepted: 06/19/2014] [Indexed: 02/06/2023] Open
Abstract
Previous studies had shown that elevated admission plasma glucose (APG) could increase mortality rate and serious complications of acute myocardial infarction (AMI), but whether fasting plasma glucose (FPG) had the same role remains controversial. In this retrospective study, 253 cases of AMI patients were divided into diabetic (n = 87) and nondiabetic group (n = 166). Our results showed that: compared with the nondiabetic patients, diabetic patients had higher APG, FPG, higher plasma triglyceride, higher rates of painless AMI (P < 0.01), non-ST-segment elevation myocardial infarction (NSTEMI), and reinfraction (P < 0.05). They also had lower high density lipoprotein cholesterol and rate of malignant arrhythmia, but in-hospital mortality rate did not differ significantly (P > 0.05). While nondiabetic patients were subgrouped in terms of APG and FPG (cut points were 11.1 mmol/L and 7.0 mmol/L, resp.), the mortality rate had significant difference (P < 0.01), whereas glucose level lost significance in diabetic group. Multivariate logistic regression analysis showed that FPG (OR: 2.014; 95% confidence interval: 1.296-3.131; p < 0.01) but not APG was independent predictor of in-hospital mortality for nondiabetic patients. These results indicate that FPG can be an independent predictor for mortality in nondiabetic female patients with AMI.
Collapse
Affiliation(s)
- Guojing Luo
- Department of Endocrinology and Metabolism, the Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, Guangdong 519000, China
| | - Hong Liu
- Department of Endocrinology and Metabolism, the Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, Guangdong 519000, China
| | - Shunkui Luo
- Department of Endocrinology and Metabolism, the Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, Guangdong 519000, China
| | - Fang Li
- Department of Endocrinology and Metabolism, the Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, Guangdong 519000, China
| | - Minhong Su
- Department of Endocrinology and Metabolism, the Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, Guangdong 519000, China
| | - Hongyun Lu
- Department of Endocrinology and Metabolism, the Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, Guangdong 519000, China
- *Hongyun Lu:
| |
Collapse
|
15
|
Sabe AA, Elmadhun NY, Robich MP, Dalal RS, Sellke FW. Does resveratrol improve insulin signaling in chronically ischemic myocardium? J Surg Res 2013; 183:531-6. [PMID: 23622724 PMCID: PMC3740092 DOI: 10.1016/j.jss.2013.03.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Revised: 02/20/2013] [Accepted: 03/01/2013] [Indexed: 12/31/2022]
Abstract
BACKGROUND Resveratrol is a naturally occurring polyphenol believed to be cardioprotective. We previously demonstrated that resveratrol improves insulin signaling and glucose metabolism in liver and skeletal muscle of swine with metabolic syndrome. Although resveratrol has metabolic benefits in peripheral tissues, its effect on insulin signaling in ischemic myocardium (IM) is unclear. Therefore, we developed a clinically relevant swine model of metabolic syndrome and chronic myocardial ischemia to investigate the effects of resveratrol on insulin signaling in cardiac tissue. MATERIALS AND METHODS Thirteen male Yorkshire swine were fed a high-cholesterol diet for 4 wk then underwent surgical placement of an ameroid constrictor to their circumflex artery to induce chronic myocardial ischemia. The high-cholesterol control group was given no drug (n = 7). The experimental group was provided the same diet and received supplemental resveratrol (100 mg/kg/d) (n = 6). Tissue was harvested 7 wk after ameroid placement for western blot and histological analyses. RESULTS In IM, there was no significant difference between the two groups in the insulin signaling markers studied. In nonischemic myocardium, there was a significant decrease in phosphorylated AMP-activated protein kinase α (P = 0.021) in the group treated with resveratrol; otherwise, there were no significant differences between the groups. Immunostaining for glucose transporter 4 and Periodic acid-Schiff staining for myocardial glycogen stores was similar between the groups. CONCLUSIONS Resveratrol has complex effects on glucose metabolism. Although prior studies demonstrated that resveratrol supplementation improves insulin sensitivity in peripheral tissues, in chronically IM, there are no significant alterations.
Collapse
Affiliation(s)
- Ashraf A. Sabe
- Division of Cardiothoracic Surgery, Cardiovascular Research Center, Warren Alpert School of Medicine, Brown University, Providence, Rhode Island
| | - Nassrene Y. Elmadhun
- Division of Cardiothoracic Surgery, Cardiovascular Research Center, Warren Alpert School of Medicine, Brown University, Providence, Rhode Island
| | - Michael P. Robich
- Division of Cardiothoracic Surgery, Cardiovascular Research Center, Warren Alpert School of Medicine, Brown University, Providence, Rhode Island
| | - Rahul S. Dalal
- Division of Cardiothoracic Surgery, Cardiovascular Research Center, Warren Alpert School of Medicine, Brown University, Providence, Rhode Island
| | - Frank W. Sellke
- Division of Cardiothoracic Surgery, Cardiovascular Research Center, Warren Alpert School of Medicine, Brown University, Providence, Rhode Island
| |
Collapse
|
16
|
Elmadhun NY, Sabe AA, Robich MP, Chu LM, Lassaletta AD, Sellke FW. The pig as a valuable model for testing the effect of resveratrol to prevent cardiovascular disease. Ann N Y Acad Sci 2013; 1290:130-5. [DOI: 10.1111/nyas.12216] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Nassrene Y. Elmadhun
- Division of Cardiothoracic Surgery; Cardiovascular Research Center; Warren Alpert School of Medicine, Brown University; Providence Rhode Island
| | - Ashraf A. Sabe
- Division of Cardiothoracic Surgery; Cardiovascular Research Center; Warren Alpert School of Medicine, Brown University; Providence Rhode Island
| | - Michael P. Robich
- Division of Cardiothoracic Surgery; Cardiovascular Research Center; Warren Alpert School of Medicine, Brown University; Providence Rhode Island
| | - Louis M. Chu
- Division of Cardiothoracic Surgery; Cardiovascular Research Center; Warren Alpert School of Medicine, Brown University; Providence Rhode Island
| | - Antonio D. Lassaletta
- Division of Cardiothoracic Surgery; Cardiovascular Research Center; Warren Alpert School of Medicine, Brown University; Providence Rhode Island
| | - Frank W. Sellke
- Division of Cardiothoracic Surgery; Cardiovascular Research Center; Warren Alpert School of Medicine, Brown University; Providence Rhode Island
| |
Collapse
|
17
|
Li H, Bian Y, Zhang N, Guo J, Wang C, Lau WB, Xiao C. Intermedin protects against myocardial ischemia-reperfusion injury in diabetic rats. Cardiovasc Diabetol 2013; 12:91. [PMID: 23777472 PMCID: PMC3703263 DOI: 10.1186/1475-2840-12-91] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 06/14/2013] [Indexed: 12/20/2022] Open
Abstract
Background Diabetic patients, through incompletely understood mechanisms, endure exacerbated ischemic heart injury compared to non-diabetic patients. Intermedin (IMD) is a novel calcitonin gene-related peptide (CGRP) superfamily member with established cardiovascular protective effects. However, whether IMD protects against diabetic myocardial ischemia/reperfusion (MI/R) injury is unknown. Methods Diabetes was induced by streptozotocin in Sprague–Dawley rats. Animals were subjected to MI via left circumflex artery ligation for 30 minutes followed by 2 hours R. IMD was administered formally 10 minutes before R. Outcome measures included left ventricular function, oxidative stress, cellular death, infarct size, and inflammation. Results IMD levels were significantly decreased in diabetic rats compared to control animals. After MI/R, diabetic rats manifested elevated intermedin levels, both in plasma (64.95 ± 4.84 pmol/L, p < 0.05) and myocardial tissue (9.8 ± 0.60 pmol/L, p < 0.01) compared to pre-MI control values (43.62 ± 3.47 pmol/L and 4.4 ± 0.41). IMD administration to diabetic rats subjected to MI/R decreased oxidative stress product generation, apoptosis, infarct size, and inflammatory cytokine release (p < 0.05 or p < 0.01). Conclusions By reducing oxidative stress, inflammation, and apoptosis, IMD may represent a promising novel therapeutic target mitigating diabetic ischemic heart injury.
Collapse
|
18
|
Whittington HJ, Babu GG, Mocanu MM, Yellon DM, Hausenloy DJ. The diabetic heart: too sweet for its own good? Cardiol Res Pract 2012; 2012:845698. [PMID: 22462028 PMCID: PMC3296224 DOI: 10.1155/2012/845698] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Accepted: 11/14/2011] [Indexed: 01/23/2023] Open
Abstract
Diabetes mellitus is a major risk factor for ischemic heart disease (IHD). Patients with diabetes and IHD experience worse clinical outcomes, suggesting that the diabetic heart may be more susceptible to ischemia-reperfusion injury (IRI). In contrast, the animal data suggests that the diabetic heart may be either more, equally, or even less susceptible to IRI. The conflicting animal data may be due to the choice of diabetic and/or IRI animal model. Ischemic conditioning, a phenomenon in which the heart is protected against IRI by one or more brief nonlethal periods of ischemia and reperfusion, may provide a novel cardioprotective strategy for the diabetic heart. Whether the diabetic heart is amenable to ischemic conditioning remains to be determined using relevant animal models of IRI and/or diabetes. In this paper, we review the limitations of the current experimental models used to investigate IRI and cardioprotection in the diabetic heart.
Collapse
Affiliation(s)
- Hannah J. Whittington
- The Hatter Cardiovascular Institute, University College London, 67 Chenies Mews, London, WC1E 6HX, UK
| | - Girish G. Babu
- The Hatter Cardiovascular Institute, University College London, 67 Chenies Mews, London, WC1E 6HX, UK
| | - Mihaela M. Mocanu
- The Hatter Cardiovascular Institute, University College London, 67 Chenies Mews, London, WC1E 6HX, UK
| | - Derek M. Yellon
- The Hatter Cardiovascular Institute, University College London, 67 Chenies Mews, London, WC1E 6HX, UK
| | - Derek J. Hausenloy
- The Hatter Cardiovascular Institute, University College London, 67 Chenies Mews, London, WC1E 6HX, UK
| |
Collapse
|
19
|
Zhong MF, Shen WL, Wang J, Yang J, Yuan WJ, He J, Wu PP, Wang Y, Zhang L, Higashino H, Chen H. Paradoxical effects of streptozotocin-induced diabetes on endothelial dysfunction in stroke-prone spontaneously hypertensive rats. J Physiol 2011; 589:5153-65. [PMID: 21930604 PMCID: PMC3225671 DOI: 10.1113/jphysiol.2011.213686] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Non-technical summary Elevated blood glucose is generally regarded as one of the risk factors that lead to coronary heart disease in patients with type 2 diabetes. However, our studies show that after inducing short-term damage, high blood glucose subsequently provides paradoxical protection for vessel function of animals with high blood pressure. Vessels can adapt to sustained high blood glucose and produce different stress proteins to counteract, to some extent, the damage brought about by hypertension. The results help us understand part of the basis for vessel adaptation in diabetes. The implication for treatment of diabetes is that if the patients have long-standing diabetes and established cardiovascular disease, the target of blood glucose lowering should be less stringent and reached gradually to avoid abrupt cancellation of the pre-existing adaptations. Abstract Although both diabetes and hypertension are risk factors for cardiovascular disease, the role of hyperglycaemia per se in endothelial dysfunction is controversial. This study was designed to examine whether hyperglycaemia, or streptozotocin-induced diabetes, could aggravate endothelial dysfunction in stroke-prone spontaneously hypertensive rats (SHRSP). Hyperglycaemia was induced by streptozotocin in 2-month-old SHRSP and age-matched normotensive Wistar–Kyoto (WKY) rats. The aorta was isolated 8 weeks after induction of hyperglycaemia to record its function and to examine its morphology with transmission electron microscopy. Endothelial/inducible nitric oxide synthase (eNOS/iNOS) and inducible/constitutive haem oxygenase (HO-1/HO-2) levels were determined with Western blotting. Aortic endothelial function and production of reactive oxygen species and nitric oxide were assayed after incubation in vitro in hyperglycaemic, hyperosmolar solution. Streptozotocin-induced diabetes of 8 weeks duration did not result in endothelial dysfunction in normotensive WKY rats. In contrast, hyperglycaemic WKY rats showed significantly enhanced endothelium-dependent vasodilatation, which was abrogated by simultaneous blocking of NOS and HO. The enhanced vasodilatation was associated with elevation of vascular eNOS and HO-1. Significant endothelial dysfunction and massive macrophage–monocyte infiltration were found in SHRSP aorta (the ratio of the number of macrophages to endothelial cells in the intima, expressed as a percentage, was 20.9 ± 2.8% in SHRSP versus 1.9 ± 0.5% in WKY rats, P < 0.01), which was attenuated significantly in hyperglycaemic SHRSP (11.3 ± 1.6%, P < 0.01 versus SHRSP). Acute hyperglycaemia (10 min) aggravated endothelial dysfunction in SHRSP, with a marked increase in intracellular reactive oxygen species and NO production. Sustained in vitro incubation in hyperglycaemic/hyperosmolar conditions (addition of an extra 50 mmol L−1 of glucose or mannitol to the usual buffer, to produce a final osmolarity of 350 mosmol L−1) for 5 h enhanced endothelium-dependent vasodilatation, with elevated vessel NO production and upregulation of eNOS/HO-1 proteins. Sustained hyperglycaemia does not aggravate endothelial dysfunction and macrophage infiltration in SHRSP. Hyperglycaemia/hyperosmolarity-induced upregulation of eNOS and HO-1 may play a role in this paradoxical adaptation of endothelial function.
Collapse
Affiliation(s)
- Mei-Fang Zhong
- Department of Pharmacology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Rodrigues B, Rosa KT, Medeiros A, Schaan BD, Brum PC, De Angelis K, Irigoyen MC. Hyperglycemia can delay left ventricular dysfunction but not autonomic damage after myocardial infarction in rodents. Cardiovasc Diabetol 2011; 10:26. [PMID: 21470409 PMCID: PMC3084163 DOI: 10.1186/1475-2840-10-26] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Accepted: 04/06/2011] [Indexed: 01/11/2023] Open
Abstract
Background Although clinical diabetes mellitus is obviously a high risk factor for myocardial infarction (MI), in experimental studies disagreement exists about the sensitivity to ischemic injury of an infarcted myocardium. Recently, our group demonstrated that diabetic animals presented better cardiac function recovery and cellular resistance to ischemic injury than nondiabetics. In the present study, we evaluated the chronic effects of MI on left ventricular (LV) and autonomic functions in streptozotocin (STZ) diabetic rats. Methods Male Wistar rats were divided into 4 groups: control (C, n = 15), diabetes (D, n = 16), MI (I, n = 21), and diabetes + MI (DI, n = 30). MI was induced 15 days after diabetes (STZ) induction. Ninety days after MI, LV and autonomic functions were evaluated (8 animals each group). Left ventricular homogenates were analyzed by Western blotting to evaluate the expression of calcium handling proteins. Results MI area was similar in infarcted groups (~43%). Ejection fraction and +dP/dt were reduced in I compared with DI. End-diastolic pressure was additionally increased in I compared with DI. Compared with DI, I had increased Na+-Ca2+ exchange and phospholamban expression (164%) and decreased phosphorylated phospholamban at serine16 (65%) and threonine17 (70%) expression. Nevertheless, diabetic groups had greater autonomic dysfunction, observed by baroreflex sensitivity and pulse interval variability reductions. Consequently, the mortality rate was increased in DI compared with I, D, and C groups. Conclusions LV dysfunction in diabetic animals was attenuated after 90 days of myocardial infarction and was associated with a better profile of calcium handling proteins. However, this positive adaptation was not able to reduce the mortality rate of DI animals, suggesting that autonomic dysfunction is associated with increased mortality in this group. Therefore, it is possible that the better cardiac function has been transitory, and the autonomic dysfunction, more prominent in diabetic group, may lead, in the future, to the cardiovascular damage.
Collapse
Affiliation(s)
- Bruno Rodrigues
- Human Movement Laboratory, São Judas Tadeu University, São Paulo, Brazil.
| | | | | | | | | | | | | |
Collapse
|
21
|
Rodrigues B, Figueroa DMT, Fang J, Rosa KT, Llesuy S, De Angelis K, Irigoyen MC. Short-term diabetes attenuates left ventricular dysfunction and mortality rates after myocardial infarction in rodents. Clinics (Sao Paulo) 2011; 66:1437-42. [PMID: 21915497 PMCID: PMC3161225 DOI: 10.1590/s1807-59322011000800022] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2011] [Accepted: 05/02/2011] [Indexed: 01/24/2023] Open
Abstract
OBJECTIVES To investigate the effects of hyperglycemia on left ventricular dysfunction, morphometry, myocardial infarction area, hemodynamic parameters, oxidative stress profile, and mortality rate in rats that had undergone seven days of myocardial infarction. INTRODUCTION Previous research has demonstrated that hyperglycemia may protect the heart against ischemic injury. METHODS Male Wistar rats were divided into four groups: control-sham, diabetes-sham, myocardial infarction, and diabetes + myocardial infarction. Myocardial infarction was induced 14 days after diabetes induction. Ventricular function and morphometry, as well as oxidative stress and hemodynamic parameters, were evaluated after seven days of myocardial infarction. RESULTS The myocardial infarction area, which was similar in the infarcted groups at the initial evaluation, was reduced in the diabetes + myocardial infarction animals (23 ± 3%) when compared with the myocardial infarction (42 ± 7%, p < 0.001) animals at the final evaluation. The ejection fraction (22%, p = 0.003), velocity of circumferential fiber shortening (30%, p = 0.001), and left ventricular isovolumetric relaxation time (26%, p = 0.002) were increased in the diabetes + myocardial infarction group compared with the myocardial infarction group. The diabetes-sham and diabetes + myocardial infarction groups displayed increased catalase concentrations compared to the control-sham and myocardial infarction groups (diabetes-sham: 32 ± 3; diabetes + myocardial infarction: 35 ± 0.7; control-sham: 12 ± 2; myocardial infarction: 16 ± 0.1 pmol min⁻¹ mg⁻¹ protein). The levels of thiobarbituric acid-reactive substances were reduced in the diabetes-sham rats compared to the control-sham rats. These positive adaptations were reflected in a reduced mortality rate in the diabetes + myocardial infarction animals (18.5%) compared with the myocardial infarction animals (40.7%, p = 0.001). CONCLUSIONS These data suggest that short-term hyperglycemia initiates compensatory mechanisms, as demonstrated by increased catalase levels, which culminate in improvements in the ventricular response, infarcted area, and mortality rate in diabetic rats exposed to ischemic injury.
Collapse
Affiliation(s)
- Bruno Rodrigues
- Human Movement Laboratory, São Judas Tadeu University, São Paulo, SP, Brazil.
| | | | | | | | | | | | | |
Collapse
|
22
|
Chu LM, Osipov RM, Robich MP, Feng J, Sheller MR, Sellke FW. Effect of thrombin fragment (TP508) on myocardial ischemia reperfusion injury in a model of type 1 diabetes mellitus. Circulation 2010; 122:S162-9. [PMID: 20837908 DOI: 10.1161/circulationaha.109.928374] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND We investigated the efficacy of novel thrombin fragment TP508 on ischemia-reperfusion injury using a porcine model of type 1 diabetes mellitus. METHODS AND RESULTS Alloxan-induced diabetic male Yucatan swine underwent 60 minutes of mid-left anterior descending coronary artery occlusion, followed by 120 minutes of reperfusion. Fifty minutes into ischemia, animals received either placebo (DM; n=8) or TP508 as a bolus of 1 mg/kg followed by infusion at 2.5 mg/kg per hour (DMT; n=8). Hemodynamic parameters and myocardial function were monitored. Monastryl blue/triphenyl tetrazolium chloride staining was used to assess sizes of the areas at risk and infarction. Coronary microvascular reactivity was measured and expression of cell survival and proapoptotic proteins quantified. Preoperative serum glucose values were similar between groups (309±57 mg/dL in DM versus 318±67 mg/dL in DMT; P=0.92). Infarct size was smaller in the TP508-treated group (5.3±1.9% in DMT versus 19.4±5.6% in DM; P=0.03). There was no statistically significant difference in global or regional left ventricular function between groups. Endothelium-dependent microvessel relaxation was moderately improved in the DMT group (P=0.09), whereas endothelium-independent relaxation was similar between groups. The expression of cell survival proteins Akt, phospho-p38, and mammalian target of rapamycin was higher in the areas at risk of DMT animals compared with DM animals (P<0.05), and expressions of proapoptotic glycogen synthase kinase 3β and caspase 3 were lower in the DMT group (P<0.05). CONCLUSIONS This study demonstrates that, in type 1 diabetic swine, TP508 reduces infarct size after ischemia-reperfusion. Thus, TP508 may offer a novel approach in cardioprotection from ischemia-reperfusion injury in diabetic patients.
Collapse
Affiliation(s)
- Louis M Chu
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | | | | | | | | | | |
Collapse
|