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Wu CY, Lin YH, Hsieh HH, Chung YH, Hsu ST, Peng SL. The effect of estrogen therapy on cerebral metabolism in diabetic female rats. Comput Struct Biotechnol J 2023; 21:4769-4776. [PMID: 37841332 PMCID: PMC10570627 DOI: 10.1016/j.csbj.2023.09.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Revised: 09/20/2023] [Accepted: 09/24/2023] [Indexed: 10/17/2023] Open
Abstract
The impact of estrogen on brain function, especially in individuals with diabetes, remains uncertain. This study aims to compare cerebral glucose metabolism levels in intact rats, ovariectomized (OVX) rats, and 17β-estradiol (E2)-treated OVX diabetic female rats. Sixteen rats were administered a single intraperitoneal injection of 70 mg/kg streptozotocin (STZ) to induce diabetes (intact, n = 6; OVX, n = 6; OVX+E2-treated, n = 4). Additionally, 18 rats received an equivalent solvent dose via intraperitoneal injection (intact, n = 6; OVX, n = 6; OVX+E2-treated, n = 6). After 4 weeks of STZ or solvent administration, positron emission tomography scans with 18F-fluorodeoxyglucose (18F-FDG) injection were employed to assess cerebral glucose metabolism. The diabetic rats exhibited substantial reductions in 18F-FDG uptake across all brain regions (all P < 0.01), in contrast to the control rats. Moreover, intact and OVX + E2-treated diabetic female rats displayed more pronounced decreases in cerebral glucose metabolism in the amygdala and hippocampus compared to OVX diabetic female rats (P < 0.05). These findings suggest that diabetes creates an environment wherein estrogen exacerbates neuropathology and intensifies neuronal activity.
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Affiliation(s)
- Chun-Yi Wu
- Department of Biomedical Imaging and Radiological Sciences, National Yang Ming Chiao Tung University, Taipei Branch, Taipei, Taiwan
| | - Yu-Hsin Lin
- Department of Pharmacy, National Yang Ming Chiao Tung University, Taipei Branch, Taipei, Taiwan
- Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan
| | - Hsin-Hua Hsieh
- Department of Biomedical Imaging and Radiological Sciences, National Yang Ming Chiao Tung University, Taipei Branch, Taipei, Taiwan
| | - Yi-Hsiu Chung
- Center for Advanced Molecular Imaging and Translation, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Shih-Ting Hsu
- Center for Advanced Molecular Imaging and Translation, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Shin-Lei Peng
- Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan
- Neuroscience and Brain Disease Center, China Medical University, Taiwan
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Sartoretto SM, Santos FF, Costa BP, Ceravolo GS, Santos-Eichler R, Carvalho MHC, Fortes ZB, Akamine EH. Involvement of inducible nitric oxide synthase and estrogen receptor ESR2 (ERβ) in the vascular dysfunction in female type 1 diabetic rats. Life Sci 2018; 216:279-286. [PMID: 30447304 DOI: 10.1016/j.lfs.2018.11.030] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 10/31/2018] [Accepted: 11/13/2018] [Indexed: 11/25/2022]
Abstract
AIMS Inflammation is involved in diabetes-related vascular dysfunction. Estrogen receptor ESR2/ERβ induces the expression of inducible nitric oxide (NO) synthase (iNOS) and inflammation. The present study investigated the effect of alloxan-induced type 1 diabetes on the iNOS and ESR2 expression and the effect of the chronic iNOS inhibition on the vascular smooth muscle dysfunction in diabetic female rats. In addition, we evaluated the involvement of ESR2 in iNOS expression. MAIN METHODS Alloxan-induced diabetic female rats were treated or not with iNOS inhibitor (L-NIL). iNOS and ESR2 immunostaining, S-nitrosylated proteins and IL-1β protein expression in aorta and plasmatic NO levels were analyzed. Contractile response to noradrenaline was analyzed in endothelium-denuded aorta. iNOS mRNA expression was analyzed in isolated aortic smooth muscle cells (ASMCs) of female rats, incubated with 22 mM glucose and an ESR2 antagonist. KEY FINDINGS Aortic iNOS and ESR2 immunostaining, S-nitrosylated proteins, IL-1β protein expression and plasmatic NO levels were all increased, whereas noradrenaline-induced contraction was reduced in aorta of diabetic female rats. With the exception of iNOS and ESR2 immunostaining, all these parameters were corrected by L-NIL treatment. High glucose increased iNOS mRNA expression in ASMCs, which was reduced by an ESR2 antagonist. SIGNIFICANCE We demonstrated that increased iNOS-NO contributed to the impairment of the contractile response of aortic smooth muscle cells in female type 1 diabetic rats and that increased expression of iNOS may involve the participation of ESR2/ERβ.
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Affiliation(s)
- Simone Marcieli Sartoretto
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Fernanda Fernandes Santos
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Beatriz Pereira Costa
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Graziela Scalianti Ceravolo
- Department of Physiological Sciences, Biological Sciences Center, State University of Londrina, Paraná, Brazil
| | - Rosângela Santos-Eichler
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | | | - Zuleica Bruno Fortes
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Eliana Hiromi Akamine
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
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3
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Yehuda I, Madar Z, Leikin-Frenkel A, Tamir S. Glabridin, an isoflavan from licorice root, downregulates iNOS expression and activity under high-glucose stress and inflammation. Mol Nutr Food Res 2015; 59:1041-52. [PMID: 25737160 DOI: 10.1002/mnfr.201400876] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Revised: 02/14/2015] [Accepted: 02/16/2015] [Indexed: 12/13/2022]
Abstract
SCOPE In females, hyperglycemia abolishes estrogen-vascular protection, leading to inflammation and oxidative stress that are related to diabetes-associated cardiovascular complications. Such knowledge led us to examine the potential of glabridin, as a replacement of estrogen anti-inflammatory activity under high-glucose conditions. METHODS AND RESULTS In macrophage-like cells, chronic glucose stress (28 and 44 mM) upregulated inducible nitric oxide synthase (iNOS) mRNA expression by 42 and 189%, respectively. Pretreatment with glabridin, under chronic glucose stress, downregulated the LPS-induced nitric oxide secretion and nitrotyrosine formation, by 39 and 21%, respectively. Pretreatment with estradiol did not prevent the LPS-induced nitrotyrosine formation. Furthermore, glabridin, brought about a decrease in the LPS-induced iNOS mRNA expression by 48%, as compared to cells pretreated with estradiol. Glabridin decreased protein levels of liver iNOS by 69% in adult mouse offspring which developed hyperglycemia after early fetal exposure to a saturated fatty acid-enriched maternal diet. Glabridin also decreased liver nitrotyrosine levels in offspring of regular diet-fed mothers after further receiving high-fat diet. CONCLUSION Such results indicate that glabridin retains anti-inflammatory abilities to regulate the synthesis and activity of iNOS under high-glucose levels, implying that a glabridin supplement may serve as an anti-inflammatory agent in diabetes-related vascular dysfunction.
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Affiliation(s)
- Itamar Yehuda
- Laboratory of Human Health and Nutrition Sciences, MIGAL-Galilee Research Institute, Kiryat-Shmona, Israel.,The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Jerusalem, Israel
| | - Zecharia Madar
- The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Jerusalem, Israel
| | - Alicia Leikin-Frenkel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.,Sheba Medical Center, Bert W. Strassburger Lipid Center, Tel-Hashomer, Israel
| | - Snait Tamir
- Laboratory of Human Health and Nutrition Sciences, MIGAL-Galilee Research Institute, Kiryat-Shmona, Israel.,Faculty of Sciences and Technology, Tel-Hai Academic College, Upper Galilee, Israel
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4
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Efficacy of female rat models in translational cardiovascular aging research. J Aging Res 2014; 2014:153127. [PMID: 25610649 PMCID: PMC4294461 DOI: 10.1155/2014/153127] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 12/05/2014] [Accepted: 12/05/2014] [Indexed: 01/11/2023] Open
Abstract
Cardiovascular disease is the leading cause of death in women in the United States. Aging is a primary risk factor for the development of cardiovascular disease as well as cardiovascular-related morbidity and mortality. Aging is a universal process that all humans undergo; however, research in aging is limited by cost and time constraints. Therefore, most research in aging has been done in primates and rodents; however it is unknown how well the effects of aging in rat models translate into humans. To compound the complication of aging gender has also been indicated as a risk factor for various cardiovascular diseases. This review addresses the systemic pathophysiology of the cardiovascular system associated with aging and gender for aging research with regard to the applicability of rat derived data for translational application to human aging.
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Kautzky-Willer A, Stich K, Hintersteiner J, Kautzky A, Kamyar MR, Saukel J, Johnson J, Lemmens-Gruber R. Sex-specific-differences in cardiometabolic risk in type 1 diabetes: a cross-sectional study. Cardiovasc Diabetol 2013; 12:78. [PMID: 23705959 PMCID: PMC3666903 DOI: 10.1186/1475-2840-12-78] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Accepted: 05/19/2013] [Indexed: 12/25/2022] Open
Abstract
Background Little is known about the impact of sex-specific differences in the management of type 1 diabetes (T1DM). Thus, we evaluated the influence of gender on risk factors, complications, clinical care and adherence in patients with T1DM. Methods In a cross-sectional study, sex-specific disparities in glycaemic control, cardiovascular risk factors, diabetic complications, concomitant medication use and adherence to treatment recommendations were evaluated in 225 consecutive patients (45.3% women) who were comparable with respect to age, diabetes duration, and body mass index. Results Although women with T1DM had a higher total cholesterol than men, triglycerides were higher in obese men and males with HbA1c>7% than in their female counterparts. No sex differences were observed in glycaemic control and in micro- or macrovascular complications. However, the subgroup analysis showed that nephropathy was more common in obese men, hyperlipidaemic women and all hypertensive patients, whereas peripheral neuropathy was more common in hyperlipidaemic women. Retinopathy was found more frequently in women with HbA1c>7%, obese men and in both sexes with a long duration of diabetes. The multivariate analysis revealed that microvascular complications were associated with the duration of disease and BMI in both sexes and with hyperlipidaemia in males. The overall adherence to interventions according to the guidelines was higher in men than in women. This adherence was concerned particularly with co-medication in patients diagnosed with hypertension, aspirin prescription in elderly patients and the achievement of target lipid levels following the prescription of statins. Conclusions Our data showed sex differences in lipids and overweight in patients with T1DM. Although glycaemic control and the frequency of diabetic complications were comparable between the sexes, the overall adherence to guidelines, particularly with respect to the prescription of statins and aspirin, was lower in women than in men.
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Affiliation(s)
- Alexandra Kautzky-Willer
- Gender Medicine Unit, Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
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6
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Krishnan S, Fields DA, Copeland KC, Blackett PR, Anderson MP, Gardner AW. Sex differences in cardiovascular disease risk in adolescents with type 1 diabetes. ACTA ACUST UNITED AC 2012; 9:251-8. [PMID: 22795492 DOI: 10.1016/j.genm.2012.05.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Revised: 05/11/2012] [Accepted: 05/26/2012] [Indexed: 10/28/2022]
Abstract
BACKGROUND Cardiovascular disease is seen at a younger age and at a higher prevalence in patients with type 1 diabetes than in the general population. It is well described that women with type 1 diabetes have a higher relative risk of cardiovascular disease than men with type 1 diabetes, unlike that seen in the general population. The pathophysiology behind this is unknown. OBJECTIVE We performed a cross-sectional study to examine sex differences in cardiovascular disease risk factors in adolescents with type 1 diabetes between ages 13 and 20 years, compared with children of a similar age without type 1 diabetes. METHODS All patients underwent a dual energy x-ray absorptiometry scan to measure body composition and a pulse wave test measure of arterial elasticity. Fasting serum lipid levels, apolipoprotein B, and apolipoprotein C-III levels were measured in each patient. Twenty-nine children with type 1 diabetes (10 girls, 19 boys) and 37 healthy children (18 girls, 19 boys) participated. RESULTS Although no sex differences for body mass index (P = 0.91) and glycosylated hemoglobin (P = 0.69) were seen, girls with type 1 diabetes had a significantly higher percent trunk fat compared with boys (P = 0.004). No sex differences were found (P > 0.05) for percent trunk fat in adolescents without diabetes. There was no sex difference among any other cardiovascular risk factors in either children with or without diabetes. CONCLUSIONS Female adolescents with type 1 diabetes have more centrally distributed fat, which may contribute to their relatively higher cardiovascular disease risk. Attenuation of the central distribution of fat through exercise and dietary modifications may help ameliorate their subsequent cardiovascular disease burden.
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Affiliation(s)
- Sowmya Krishnan
- Children's Medical Research Institute Diabetes and Metabolic Research Program, Section of Diabetes and Endocrinology, Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
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7
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Akar F, Pektas MB, Tufan C, Soylemez S, Sepici A, Ulus AT, Gokalp B, Ozturk K, Surucu HS. Resveratrol shows vasoprotective effect reducing oxidative stress without affecting metabolic disturbances in insulin-dependent diabetes of rabbits. Cardiovasc Drugs Ther 2012; 25:119-31. [PMID: 20676927 DOI: 10.1007/s10557-010-6255-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
PURPOSE Resveratrol has been shown to have vasoprotective effects by upregulating oxidative defense mechanisms in a variety of pathophysiological conditions. However, the effect of resveratrol on diabetic oxidative stress and vascular and metabolic abnormalities is not completely understood. Therefore, this study was designed to evaluate whether long-term resveratrol supplementation has a protective effect on vascular function and integrity in association with metabolic parameters and oxidative stress in insulin-dependent diabetes. METHODS Diabetes was induced in rabbits with alloxan and maintained for 8 weeks. We used a resveratrol dose of 5 mg/L (10 weeks, starting 14 days before alloxan injection) and 50 mg/L (8 or 10 weeks, starting concomitantly or 14 days before alloxan injection) in the drinking water of rabbits. RESULTS Relaxation to acetylcholine was impaired (control 75.6 ± 3.59%, versus diabetic 42.23 ± 2.53%) and contractions to phenylephrine increased (control 136.89 ± 2.27%, versus diabetic 159.37 ± 6.27%) in aortas from diabetic animals. These changes were associated with increased basal or NAD(P)H-induced superoxide production, as well as lipid peroxide and superoxide dismutase (SOD) levels in the aortic samples. The maximal relaxation to acetylcholine improved by 75.74 ± 9.04% in diabetic rabbits treated with resveratrol. The increased contractions to phenylephrine were not restored to control values after resveratrol treatments, but sensitivity to the contractions tended to decrease. Resveratrol increased nitrite/nitrate levels and suppressed basal or NAD(P)H-induced superoxide production and lipid peroxide levels in the aortas. Importantly, resveratrol increased serum insulin levels without affecting blood glucose and the lipid profile in diabetic rabbits. Using electron microscopic examinations, resveratrol was found to markedly protect the endothelial integrity from diabetes. CONCLUSION Overall, there was no noticeable difference between resveratrol treatment groups on the recovery from diabetes. Our results indicate that resveratrol alleviates type 1 diabetes-induced vasculopathy by decreasing vascular oxidative stress and thereby increasing the bioavailability of nitric oxide without changing metabolic abnormalities.
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Affiliation(s)
- Fatma Akar
- Department of Pharmacology, Faculty of Pharmacy, Gazi University, Etiler, Ankara, Turkey.
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8
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Mechanisms underlining gender differences in Phenylephrine contraction of normoglycaemic and short-term Streptozotocin-induced diabetic WKY rat aorta. Vascul Pharmacol 2011; 57:81-90. [PMID: 22172524 DOI: 10.1016/j.vph.2011.11.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Revised: 09/28/2011] [Accepted: 11/29/2011] [Indexed: 01/30/2023]
Abstract
The female gender reduces the risk, but succumbs more to cardiovascular disease. The hypothesis that short-term (8weeks) Streptozotocin-induced diabetes could produce greater female than male vascular tissue reactivity and the mechanistic basis were explored. Aortic ring responses to Phenylephrine were examined in age- and sex-matched normoglycaemic/diabetic rats. The normoglycaemic male tissue contracted significantly more than the normoglycaemic female and the male/female diabetic tissues. Endothelial-denudation, l-NAME or MB reversed these differences suggesting an EDNO-cGMP dependence. 17β-oestradiol exerted relaxant effect on all endothelium-denuded (and normoglycaemic endothelium-intact male) tissues, but not endothelium-intact normoglycaemic female. The greater male tissue contraction is attributable to absent 17β-oestradiol-modulated relaxation. Indomethacin blockade of COX attenuated male normoglycaemic and female diabetic tissue contraction (both reversed by l-NAME), but augmented diabetic male tissue contraction. These data are consistent with the raised contractile TXA(2) and PGE(2) in normoglycaemic male and diabetic female tissues, and the relaxant PGI(2) in diabetic male (and female). The higher levels of PGI(2) in the normoglycaemic and diabetic female perhaps explain their greater relaxant response to Acetylcholine compared to the respective male. In conclusion, there is an endothelium-dependent gender difference in the effect of short term diabetes on vascular tissue reactivity which is COX mediated.
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Takenouchi Y, Kobayashi T, Taguchi K, Matsumoto T, Kamata K. Gender differences in vascular reactivity of aortas from streptozotocin-induced diabetic mice. Biol Pharm Bull 2011; 33:1692-7. [PMID: 20930377 DOI: 10.1248/bpb.33.1692] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The aim of the present study was to assess gender differences in diabetes-related vascular reactivity in murine aortas. Diabetes is a risk factor for ischemic heart disease, cerebral ischemia, and atherosclerosis, conditions in which endothelial dysfunction plays a pathogenetic role. We examined vascular responses in aortas isolated from streptozotocin (STZ)-induced type 1 diabetic mice and age-matched control mice, and looked for gender differences in the diabetes-induced changes in these responses. For each gender, the plasma adiponectin levels were lower in diabetic mice than in the controls, and they were significantly higher in females than in males. The acetylcholine (ACh)-induced endothelium-dependent relaxation of aortic rings was impaired (vs. that in the age-matched controls) in diabetic male mice, but not in diabetic female mice. The sodium nitroprusside-induced endothelium-independent aortic relaxation was not altered by diabetes in either male or female mice. The norepinephrine-induced aortic contraction was enhanced (vs. that in the control group) in diabetic female mice, but not in diabetic male mice, whereas in the presence of N(G)-nitro-L-arginine neither gender exhibited a significant diabetes-induced change in this contraction. The clonidine-induced and insulin-induced endothelium-dependent aortic relaxations were impaired only in the diabetic female group (vs. the age-matched controls). These results suggest that: a) in male diabetic mice, which exhibited low adiponectin levels, these were impairments of both the aortic relaxation and nitric oxide (NO) production induced by ACh, whereas b) in female diabetic mice, there were impairments of the aortic relaxations induced by both insulin and clonidine.
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Affiliation(s)
- Yasuhiro Takenouchi
- Department of Physiology and Morphology, Institute of Medicinal Chemistry, Hoshi University, Tokyo 142–8501, Japan
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10
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Wong NL, Achike FI. Gender discrimination in the influence of hyperglycemia and hyperosmolarity on rat aortic tissue responses to insulin. ACTA ACUST UNITED AC 2010; 163:113-9. [PMID: 20434492 DOI: 10.1016/j.regpep.2010.04.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2010] [Revised: 03/11/2010] [Accepted: 04/17/2010] [Indexed: 01/14/2023]
Abstract
Hyperglycaemia initiates endothelial dysfunction causing diabetic macro- and micro-vasculopathy, the main causes of morbidity and mortality in diabetes mellitus. The vasculopathy exhibits gender peculiarities. We therefore explored gender differences in comparing the effects of hyperglycaemia (50 mM) per se with its hyperosmolar (50 mM) effects on vascular tissue responses to insulin. Endothelium-intact or denuded thoracic aortic rings from age-matched male and female Sprague-Dawley rats were incubated for 10 min or 6 h (acute versus chronic exposure) in normal, hyperglycaemic or hyperosmolar Krebs solution. Relaxant responses to insulin (6.9x10(-7)-6.9x10(-5) M) of the phenylephrine-contracted tissues were recorded. Endothelium denudation in both genders inhibited relaxation to insulin in all conditions, more significantly in female than in male tissues, suggesting the female response to insulin is more endothelium-dependent than the male. Acutely and chronically exposed normoglycemic endothelium-intact or -denuded tissues responded similarly to insulin. Chronic hyperglycemic or hyperosmolar exposure did not alter the endothelium-denuded tissue responses to insulin, whereas the responses of the endothelium-intact male and female hyperosmolar, and male hyperglycemic tissues were enhanced. The results show that insulin exerts an endothelium-dependent and independent relaxation with the female tissue responses more endothelium-dependent than the male. The data also suggest that hyperosmolarity per se enhances aortic tissue relaxant responses to insulin whereas hyperglycemia per se inhibits the same and more so in female than male tissues. These effects are endothelium-dependent.
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Affiliation(s)
- Nikki L Wong
- International Medical University, Bukit Jalil, 57000 Kuala Lumpur, Malaysia
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Takenouchi Y, Kobayashi T, Taguchi K, Matsumoto T, Kamata K. Gender differences in endothelial function in aortas from type 2 diabetic model mice. J Pharmacol Sci 2009; 111:91-9. [PMID: 19721331 DOI: 10.1254/jphs.09133fp] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Type 2 diabetes mellitus is associated with high mortality and morbidity, mainly due to coronary artery disease and atherosclerosis, although female gender is a protective factor in the development of, for example, atherosclerosis and hypertension. Our main aim was to investigate gender differences in endothelial function in aortas from type 2 diabetic model mice. The nonfasting plasma glucose level was significantly elevated in diabetic mice (both males and females). The plasma insulin level was not different between controls and diabetics (either gender). The plasma adiponectin level was decreased by diabetes, and was lower in males. In control aortas (from males or females), the clonidine-induced relaxation was abolished by Akt-inhibitor treatment. In diabetic males (versus both control males and diabetic females): a) the clonidine- and insulin-induced endothelium-dependent aortic relaxations were impaired, but the acetylcholine (ACh)-induced and sodium nitroprusside (SNP)-induced aortic relaxations were not, b) the norepinephrine (NE)-induced aortic contractile response was enhanced, c) systemic blood pressure was elevated, and d) the clonidine-stimulated Ser-473 phosphorylation of Akt in the aorta was decreased. These results suggest that endothelial functions dependent on the Akt pathway are abrogated by type 2 diabetes only in male mice.
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Affiliation(s)
- Yasuhiro Takenouchi
- Department of Physiology and Morphology, Institute of Medicinal Chemistry, Hoshi University, Japan
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Matsumoto T, Kakami M, Kobayashi T, Kamata K. Gender differences in vascular reactivity to endothelin-1 (1-31) in mesenteric arteries from diabetic mice. Peptides 2008; 29:1338-46. [PMID: 18486991 DOI: 10.1016/j.peptides.2008.04.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2008] [Revised: 04/01/2008] [Accepted: 04/03/2008] [Indexed: 01/22/2023]
Abstract
Endothelin-1 (1-31) [ET-1 (1-31)], a novel member of the ET family, comprises 31 amino acids and is derived from the selective hydrolysis of big ET-1 by chymase. Although ET-1 (1-31) reportedly exerts biological effects by direct or indirect [via its conversion to ET-1 (1-21)] mechanisms, it is unclear whether in diabetes the vascular effects of ET-1 (1-31) display gender differences. We investigated this question by exposing mesenteric artery rings to ET-1 (1-31), using arteries from mice in the early or chronic phase of diabetes. In the early stage of diabetes, the ET-1 (1-31)-induced contraction was similar between age- and sex-matched control and streptozotocin (STZ)-induced diabetic mice. In the chronic stage of diabetes, the ET-1 (1-31)-induced contraction was enhanced in diabetic female mice, but not in diabetic male mice (vs. both age-matched control and early-stage diabetic mice). This enhancement was largely prevented by Y27632 (Rho kinase inhibitor), PD98059 [inhibitor of extracellular signal related kinases 1 and 2 (ERK1/2)], or SP600125 [C-jun terminal kinase (JNK) inhibitor]. These data indicate that the ET-1 (1-31)-induced vasoconstriction in the mesenteric artery may be specifically enhanced in established diabetic female mice, and that this enhancement may be due to alterations in the activities of Rho/Rho kinase or mitogen-activated protein kinase.
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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
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Pinna C, Cignarella A, Sanvito P, Pelosi V, Bolego C. Prolonged Ovarian Hormone Deprivation Impairs the Protective Vascular Actions of Estrogen Receptor αAgonists. Hypertension 2008; 51:1210-7. [DOI: 10.1161/hypertensionaha.107.106807] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The vascular consequences of estrogen treatment may be driven by its initiation timing. We tested the hypothesis that the duration of ovarian hormone deprivation before estrogen reintroduction affects the role of estrogen as mediator of endothelial function and vascular relaxation in nondiseased vessels. Rats were ovariectomized and implanted with 17β-estradiol (E
2
) or oil capsules 1, 4, and 8 months after surgery. After the longest hypoestrogenicity period, acetylcholine-mediated aortic relaxation was attenuated and insensitive to E
2
administration despite endothelial integrity. Whereas no rapid vasorelaxant responses were elicited by an estrogen receptor (ER) β–selective agonist, responses to E
2
and an ERα selective agonist waned postovariectomy at any given time and were restored by E
2
treatment after 1 and 4 months but not 8 months postovariectomy. Accordingly, endothelial ERα mRNA and protein expression declined ≈6-fold after prolonged hypoestrogenicity and was restored by estrogen replacement starting 1 month but not 8 months postovariectomy. Furthermore, the amount of active phosphorylated endothelial NO synthase rose significantly after E
2
replacement after 1 and 4 months but not 8 months postovariectomy. The present findings document that the functional impairment of the ERα/endothelial NO synthase signaling network after an extended period of hypoestrogenicity was not restored by E
2
administration, providing experimental support to early initiation of estrogen replacement with preferential ERα targeting to improve cardiovascular outcomes.
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Affiliation(s)
- Christian Pinna
- From the Department of Pharmacological Sciences (C.P., A.C., P.S., V.P., C.B.), University of Milan, Milan, Italy; and the Department of Pharmacology and Anaesthesiology (A.C., P.S., V.P., C.B.), University of Padova, Padova, Italy
| | - Andrea Cignarella
- From the Department of Pharmacological Sciences (C.P., A.C., P.S., V.P., C.B.), University of Milan, Milan, Italy; and the Department of Pharmacology and Anaesthesiology (A.C., P.S., V.P., C.B.), University of Padova, Padova, Italy
| | - Paola Sanvito
- From the Department of Pharmacological Sciences (C.P., A.C., P.S., V.P., C.B.), University of Milan, Milan, Italy; and the Department of Pharmacology and Anaesthesiology (A.C., P.S., V.P., C.B.), University of Padova, Padova, Italy
| | - Valeria Pelosi
- From the Department of Pharmacological Sciences (C.P., A.C., P.S., V.P., C.B.), University of Milan, Milan, Italy; and the Department of Pharmacology and Anaesthesiology (A.C., P.S., V.P., C.B.), University of Padova, Padova, Italy
| | - Chiara Bolego
- From the Department of Pharmacological Sciences (C.P., A.C., P.S., V.P., C.B.), University of Milan, Milan, Italy; and the Department of Pharmacology and Anaesthesiology (A.C., P.S., V.P., C.B.), University of Padova, Padova, Italy
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14
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Rogers JL, Mitchell AR, Maric C, Sandberg K, Myers A, Mulroney SE. Effect of sex hormones on renal estrogen and angiotensin type 1 receptors in female and male rats. Am J Physiol Regul Integr Comp Physiol 2007; 292:R794-9. [PMID: 16990489 DOI: 10.1152/ajpregu.00424.2006] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Although the mechanisms are not understood, evidence suggests that 17β-estradiol (E2) confers protection from cardiovascular and renal complications in many diseases. We have reported that E2 decreases angiotensin type 1 receptors (AT1Rs) in different tissues and hypothesize that E2 exerts tonic inhibition on AT1Rs, reducing effects of ANG II. This study determined the effects of E2 and dihydrotestosterone (DHT) on cortical estrogen receptors (ERs) and glomerular AT1R binding in rats. Animals underwent sham operation, ovariectomy (Ovx) or orchidectomy (Cas) and were treated (Ovx ± E2; Cas ± DHT) for 3 wk. Cortical ERα protein was 2.5 times greater, and ERβ was 80% less in females vs. males ( P < 0.01). Glomerular AT1R binding was lower in females than males [4,657 ± 838 vs. 7,457 ± 467 counts per minute (cpm), P < 0.01]. Ovx reduced ERα protein by 50%, whereas E2 increased ERα expression after Ovx. The decrease in cortical ERα in Ovx rats was associated with a significant increase in AT1R binding (6,908 ± 609 cpm), and E2 prevented this increase. There was no change in ERα or AT1R binding following Cas ± DHT (25 mg) treatment, although Cas did elevate cortical ERβ (P < 0.01). Interestingly, the high dose DHT (200 mg) elevated ERα 150% above intact levels and profoundly decreased AT1R binding (1,824 ± 705 cpm, P < 0.001 vs. intact male). This indicates that under normal conditions, glomerular AT1R binding is significantly greater in male than female animals, which may be important in development of cardiovascular and renal disease in males. Furthermore, E2 regulates ERα and is inversely associated with glomerular AT1R binding, supporting our hypothesis that E2 tonically suppresses AT1Rs and suggesting a potential mechanism for the protective effects of estrogen.
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Affiliation(s)
- Jennifer L Rogers
- Department of Physiology and Biophysics, Georgetown University, Medical Center, Washington, DC 20057, USA
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15
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Pinna C, Bolego C, Sanvito P, Pelosi V, Baetta R, Corsini A, Gaion RM, Cignarella A. Raloxifene elicits combined rapid vasorelaxation and long-term anti-inflammatory actions in rat aorta. J Pharmacol Exp Ther 2006; 319:1444-51. [PMID: 16943257 DOI: 10.1124/jpet.106.106062] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Previous studies reported the ability of raloxifene to acutely relax arterial and venous vessels, but the underlying mechanisms are controversial. Anti-inflammatory effects of the drug have been reported in nonvascular tissues. Therefore, the aim of this study was to investigate the nature of short- and long-term effects of raloxifene on selected aspects of vascular function in rat aorta. Isometric tension changes in response to raloxifene were recorded in aortic rings from ovariectomized female rats that underwent estrogen replacement, whereas long-term experiments were performed in isolated aortic smooth muscle cells (SMCs). Raloxifene (0.1 pM-0.1 microM) induced acute vasorelaxation through endothelium- and nitric oxide (NO)-dependent, prostanoid-independent mechanisms. The relaxant response to raloxifene was significantly weaker than that to 17beta-estradiol and was sensitive to neither the nonselective estrogen receptor antagonist ICI 182,780 [7,17-[9[(4,4,5,5,5-pentafluoropentyl)sulfinyl]nonyl]estra-1,3,5(10)-triene-3,17-diol] nor a selective estrogen receptor (ER) alpha antagonist. This rapid vasorelaxant effect was retained in aortic rings from rats treated with 0.1 mg/kg, but not 1 mg/kg, lipopolysaccharide, 4 h before sacrifice. In cultured aortic SMCs, raloxifene treatment (1 nM-1 microM) for 24 h reduced inducible NO synthase activation in response to cytokines. This effect was prevented by the selective ERalpha antagonist and was associated with up-regulation of ERalpha protein levels, which dropped markedly upon cytokine stimulation. These findings illustrate the relevance of classic ER-dependent pathways to the vascular anti-inflammatory effects rather than to the nongenomic vasorelaxation induced by raloxifene and may assist in the design of novel ER isoform-selective estrogen-receptor modulators targeted to the vascular system.
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Affiliation(s)
- Christian Pinna
- Department of Pharmacological Sciences, University of Milan, Via Balzaretti 9, 20133 Milan, Italy
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16
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Schweitzer NB, Alessio HM, Berry SD, Roeske K, Hagerman AE. Exercise-induced changes in cardiac gene expression and its relation to spatial maze performance. Neurochem Int 2005; 48:9-16. [PMID: 16202479 DOI: 10.1016/j.neuint.2005.08.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2005] [Accepted: 08/23/2005] [Indexed: 10/25/2022]
Abstract
Cognitive performance is sensitive to both neural and non-neural changes induced by physical activity and inactivity. This study investigated whether access to physical activity outside a standard laboratory animal cage affected cognitive performance as measured by navigation of a spatial maze. It also examined gene expression in heart tissue for genes associated with cardiovascular function given recent reports of cognitive impairment associated with hyperlipidemia. Furthermore, we measured expression of neural-regulatory genes typically expressed in brain, but also found in cardiac tissue. Male Sprague-Dawley rats (n = 72) were separated into three groups having different access to physical activity: none outside a standard cage, twice-weekly physical activity, and every other day exercise on a running wheel. Compared with a sedentary group, spatial maze performance was enhanced in animals that had access to physical activity, either twice-weekly in a large box or every other day on a running wheel. Both the cardiovascular and neural-related genes expressed in the heart were distinguished by access to physical activity. Several genes that are associated with heart rate, cholesterol biosynthesis, blood pressure, and cell adhesion regulation, including GJA1, FDFT1, EDN1, and CD36, differed in animals based on access to physical activity. Neural-related genes expressed in cardiac tissue associated with neurite outgrowth, neuroplasticity, and neurogenesis including RTN4, HOMER2, ACTB, NCDN, KIF5B, and HMGB2, were expressed differently among the three groups. Significant shifts in ten cardiovascular and neural-related gene expressions in cardiac tissue were associated with physical activity and may have influenced learning and performance on a spatial maze.
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17
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Mukhopadhyay S, Mukherjee TK. Bridging advanced glycation end product, receptor for advanced glycation end product and nitric oxide with hormonal replacement/estrogen therapy in healthy versus diabetic postmenopausal women: A perspective. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2005; 1745:145-55. [PMID: 15890418 DOI: 10.1016/j.bbamcr.2005.03.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2005] [Revised: 03/20/2005] [Accepted: 03/22/2005] [Indexed: 12/13/2022]
Abstract
Cardiovascular diseases (CVD) are the most significant cause of death in postmenopausal women. The loss of estrogen biosynthesis with advanced age is suggested as one of the major causes of higher CVD in postmenopausal women. While some studies show beneficial effects of estrogen therapy (ET)/hormonal replacement therapy (HRT) in the cardiovascular system of healthy postmenopausal women, similar studies in diabetic counterparts contradict these findings. In particular, ET/HRT in diabetic postmenopausal women results in a seemingly detrimental effect on the cardiovascular system. In this review, the comparative role of estrogens is discussed in the context of CVD in both healthy and diabetic postmenopausal women in regard to the synthesis or expression of proinflammatory molecules like advanced glycation end products (AGEs), receptor for advanced glycation end products (RAGEs), inducible nitric oxide synthases (iNOS) and the anti-inflammatory endothelial nitric oxide synthases (eNOS). The interaction of AGE-RAGE signaling with molecular nitric oxide (NO) may determine the level of reactive oxygen species (ROS) and influence the overall redox status of the vascular microenvironment that may further determine the ultimate outcome of the effects of estrogens on the CVD in healthy versus diabetic women.
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Affiliation(s)
- Srirupa Mukhopadhyay
- Pulmonary Division, Department of Internal Medicine, University of Utah Health Science Center, Rm 725 Wintrobe Building, 26 North 1900 East, Salt Lake City, UT 84132-4701, USA
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18
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Schweitzer NB, Alessio HM, Hagerman AE, Roy S, Sen CK, Nagy S, Byrnes RN, Philip BN, Woodward JL, Wiley RL. Access to exercise and its relation to cardiovascular health and gene expression in laboratory animals. Life Sci 2005; 77:2246-61. [PMID: 16002099 DOI: 10.1016/j.lfs.2005.01.036] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2004] [Accepted: 01/28/2005] [Indexed: 11/15/2022]
Abstract
The interaction between genes and environment can influence cardiovascular disease (CVD). This 16 month study investigated if genes associated with cardiovascular (CV) regulation were expressed differently in animals having: 1) no access to physical activity or exercise (SED), 2) access to hour-long, twice weekly activity (PA), and 3) access every-other-day to a running wheel (EX). Out of 31,000 genes, a CV subset comprising 44 genes was investigated. Ten genes from this subset were expressed differently in EX compared with SED, and 34 genes were expressed differently in PA compared with SED (p<0.05). Total cholesterol (70+/-8 vs. 101+/-9 mg dl(-1)), triglycerides (104+/-8 vs. 127+/-4 mg dl(-1)), resting systolic blood pressure (130+/-3 vs. 141+/-3 mmHg), mean arterial pressure (110+/-2 vs. 120+/-2 mmHg) and heart rate (380+/-6 vs. 405+/-9 beats min(-1)) were lower in EX compared with SED (p<0.05), but intracellular adhesion molecule levels did not differ among groups. Mean gene expressions for Gja1, Fdft1, Edn1, Cd36, and Hmgb2 differed in animals according to access to physical activity. These genes play roles in heart rate, cholesterol biosynthesis, blood pressure, cell adhesion, and transcription and neurogenesis regulation, respectively. In conclusion, a total of 44 CV genes were expressed differently in SED compared to PA and EX; and SED showed more physiological evidence of CVD.
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19
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Soedamah-Muthu SS, Stehouwer CDA. Cardiovascular disease morbidity and mortality in patients with type 1 diabetes mellitus : management strategies. ACTA ACUST UNITED AC 2005; 4:75-86. [PMID: 15783245 DOI: 10.2165/00024677-200504020-00002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
There is an increased risk of cardiovascular disease (CVD) mortality and morbidity in patients with type 1 diabetes mellitus compared with the general population as shown by epidemiologic studies measuring cardiovascular endpoints, as well as by autopsy, angiographic, and coronary calcification studies. Most of the excess CVD risk associated with type 1 diabetes is concentrated in the subset of approximately 35% of patients who develop diabetic nephropathy (after 20 years of diabetes duration), who also typically have dyslipidemias, elevated blood pressure, and hyperglycemia, factors contributing to CVD. For reasons that remain speculative, the relative risks from CVD are higher in women than in men with type 1 diabetes compared with the general population, which effectively eliminates the gender differences in CVD. As in the general population and in patients with type 2 diabetes, education and lifestyle changes, interventions to reduce hyperglycemia, blood pressure, micro-albuminuria, lipid control, and the use of aspirin are important management areas in order to reduce the increased risk of CVD. Whether management with aspirin and statins should be started in type 1 diabetic patients at a younger age or at a lower risk score than in the general population is still under investigation. There is a need for a better understanding of the pathophysiology of vascular complications in type 1 diabetes, more specific risk engines in type 1 diabetes, and accurate estimations of the absolute and relative risk for CVD in order to improve management of CVD in these high-risk patients.
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Affiliation(s)
- Sabita S Soedamah-Muthu
- University Medical Center Utrecht, Julius Center for Health Sciences and Primary Care, Utrecht, The Netherlands
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20
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Bolego C, Cignarella A, Sanvito P, Pelosi V, Pellegatta F, Puglisi L, Pinna C. The Acute Estrogenic Dilation of Rat Aorta Is Mediated Solely by Selective Estrogen Receptor-α Agonists and Is Abolished by Estrogen Deprivation. J Pharmacol Exp Ther 2005; 313:1203-8. [PMID: 15722404 DOI: 10.1124/jpet.104.082867] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Estrogen is known to induce rapid vasodilatory response in isolated arteries. Because estrogen is a nonselective receptor agonist, the involvement of estrogen receptor (ER) subtypes in acute estrogenic responses has remained elusive. Acute administration of the selective ERalpha agonist 4,4',4''-(4-propyl-[(1)H]pyrazole-1,3,5-triyl) tris-phenol (PPT) to precontracted aortic rings from intact female rats dose-dependently induced an ER-dependent vascular relaxation fully overlapping to that induced by 17beta-estradiol. By contrast, the selective ERbeta agonist 2,3-bis(4-hydroxyphenyl)-propionitrile (DPN) had no acute effect on vasomotion. This short-term vasorelaxant action of PPT was abolished by the NO synthase inhibitor N(omega)-nitro-l-arginine methyl ester and by endothelium removal. In aortic tissues from ovariectomized (OVX) rats, however, neither 17beta-estradiol nor PPT induced acute vascular relaxation. The effect of PPT was restored in preparations from estrogen-replaced OVX rats, whereas DPN remained ineffective even after estrogen replacement. PPT acted through an ER-dependent mechanism, as shown by impaired response in the presence of the anti-estrogen ICI 182,780 (7alpha,17beta-[9[(4,4,5,5,5-pentafluoropentyl)sulfinyl]nonyl]estra-1,3,5(10)-triene-3,17-diol). Accordingly, isolated rat aortic endothelial cells expressed both ERalpha and ERbeta. These data show that selective ERalpha but not ERbeta agonists reproduced the acute vasodilation of estrogen via a receptor-mediated pathway in the aorta from intact as well as 17beta-estradiol-replaced OVX rats. This beneficial effect was undetectable in tissues from OVX rats. Selective pharmacological targeting of ER subtypes may thus represent a novel and promising approach in the treatment of vascular disease.
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Affiliation(s)
- Chiara Bolego
- Department of Pharmacological Sciences, University of Milan, Italy
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21
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Honisett SY, Stojanovska L, Sudhir K, Kingwell BA, Dawood T, Komesaroff PA. Hormone therapy impairs endothelial function in postmenopausal women with type 2 diabetes mellitus treated with rosiglitazone. J Clin Endocrinol Metab 2004; 89:4615-9. [PMID: 15356071 DOI: 10.1210/jc.2003-031414] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Diabetes and ovarian senescence are associated with impaired endothelial function and altered arterial mechanical properties. Alterations in normal vascular structure and functioning are the primary cause of mortality and morbidity with type 2 diabetes. Similarly, after menopause, women experience an increase in the rate of cardiovascular disease. Thiazolidinediones have exhibited a number of antiatherogenic actions in populations with type 2 diabetes. The effect of thiazolidinediones in combination with hormone therapy (HT) in postmenopausal women is, however, unknown. To assess whether HT (transdermal estradiol 50 microg and micronized progesterone (100 mg/d) affects vascular function, 21 women receiving rosiglitazone were randomly assigned to receive HT or placebo for 12 wk in a double-blind crossover design. Measures of glycemic control, lipids, blood pressure, flow-mediated dilation, and distensibility index were undertaken at baseline and after each treatment. As a result, flow-mediated dilation was significantly reduced (15.3 +/- 3.8 to 6.6 +/- 1.6%, P = 0.02) with HT, whereas lipids, blood pressure, and distensibility index were unchanged. Placebo had no significant affect on any variables. Thus, the addition of HT to rosiglitazone treatment attenuates endothelial function without altering other cardiovascular risk factors. Caution should, therefore, be exercised when considering combined treatment with thiazolidinedione and HT.
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Affiliation(s)
- Suzy Y Honisett
- Department of Medicine, Monash University, The Alfred Hospital, Commercial Road, Prahran, Victoria, Australia 3181
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22
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Maggi A, Cignarella A, Brusadelli A, Bolego C, Pinna C, Puglisi L. Diabetes undermines estrogen control of inducible nitric oxide synthase function in rat aortic smooth muscle cells through overexpression of estrogen receptor-beta. Circulation 2003; 108:211-7. [PMID: 12821541 DOI: 10.1161/01.cir.0000079311.39939.94] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Previous reports from our group have shown that 17beta-estradiol reduces the synthesis and activity of inducible nitric oxide synthase (iNOS) in rat aortic smooth muscle cells (SMC) in response to inflammatory mediators. In this study, we investigated the effect of 17beta-estradiol on iNOS function in aortic SMC from streptozotocin-diabetic rats. METHODS AND RESULTS Comparative analysis of NO release and of iNOS mRNA and protein content after 24-hour stimulation with a cytokine mixture revealed milder iNOS activation in diabetic than in control SMC. Furthermore, 17beta-estradiol dose-dependently blocked iNOS synthesis and activity in control but not in diabetic SMC. The defective estrogen response in diabetic SMC at 24 hours could not be attributed to reduced expression of estrogen receptors (ER). In fact, mRNA and protein levels of ERalpha and, to a greater extent, of ERbeta, were increased in diabetic compared with nondiabetic SMC. Cytokines decreased ERalpha and ERbeta expression in both groups. However, 17beta-estradiol dose-dependently restored the expression of ERalpha but further downregulated that of ERbeta, indicating a differential regulation of ER isoforms. CONCLUSIONS Estrogenic control of iNOS was impaired in diabetic SMC. This was associated with a larger increase of ERbeta than of ERalpha protein, whereas 17beta-estradiol regulated the two isoforms in an opposite fashion. Thus, modifications in the estrogen modulation of iNOS and in the expression pattern of ER may be involved in diabetic vascular dysfunction.
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MESH Headings
- Animals
- Aorta/enzymology
- Aorta/metabolism
- Cells, Cultured
- Cytokines/pharmacology
- Diabetes Mellitus, Experimental/chemically induced
- Diabetes Mellitus, Experimental/physiopathology
- Disease Models, Animal
- Dose-Response Relationship, Drug
- Down-Regulation/drug effects
- Drug Resistance
- Enzyme Induction/drug effects
- Estradiol/pharmacology
- Estrogen Receptor alpha
- Estrogen Receptor beta
- Male
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Nitric Oxide/metabolism
- Nitric Oxide Synthase/drug effects
- Nitric Oxide Synthase/genetics
- Nitric Oxide Synthase/metabolism
- Nitric Oxide Synthase Type II
- Nitrites/metabolism
- RNA, Messenger/metabolism
- Rats
- Rats, Sprague-Dawley
- Receptors, Estrogen/genetics
- Receptors, Estrogen/metabolism
- Streptozocin
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Affiliation(s)
- Adriana Maggi
- Department of Pharmacological Sciences and Center of Excellence on Neurodegenerative Disease, University of Milan, Italy.
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23
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Affiliation(s)
- Chara Bolego
- Department of Pharmacological Sciences, University of Milan, Via Balzaretti, 9, 20133 Milan, Italy
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24
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Hupfeld CJ, Wong GA. Molecular mechanisms of diabetic cardiovascular disease. PREVENTIVE CARDIOLOGY 2002; 5:183-7. [PMID: 12417827 DOI: 10.1111/j.1520.037x.2002.00946.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Cardiovascular disease is a major cause of morbidity and mortality in persons with diabetes mellitus. This population represents an important target for preventive therapies aimed at reducing atherosclerosis. Recent molecular research has uncovered many of the cellular mechanisms that lead to atherosclerosis in the diabetic patient. This review, part 1 of a 2-part series, is geared toward clinicians and discusses these mechanisms as they pertain to prevention of cardiovascular disease in patients with diabetes.
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Affiliation(s)
- Christopher J Hupfeld
- University of California (Davis) School of Medicine, Division of Endocrinology and Vascular Biology, Sacramento, CA 95817, USA
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25
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Martina V, Bruno GA, Origlia C, Gaia D, Trucco F, Pescarmona G. Transdermal oestradiol replacement therapy enhances platelet constitutive nitric oxide synthase activity in postmenopausal women with type 2 diabetes mellitus. Clin Endocrinol (Oxf) 2002; 57:371-5. [PMID: 12201830 DOI: 10.1046/j.1365-2265.2002.01609.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine whether treatment with transdermal oestrogen replacement therapy (TERT) in postmenopausal women with type 2 diabetes mellitus was able to increase the activity of constitutive nitric oxide synthase (cNOS) in platelets. RESEARCH DESIGN AND METHODS Eighteen postmenopausal women with type 2 diabetes mellitus (group A) were studied in basal conditions (A1) and on the 10th day of the third month of a sequential opposed TERT (A2) evaluating platelet cNOS activity measured by the conversion of radiolabelled l-arginine to l-citrulline. As a control group (B) 25 normal postmenopausal women underwent the same treatment (B1 and B2 before and during treatment, respectively). RESULTS Basal values of platelet cNOS activity were superimposable (0.6 +/- 0.1 vs. 0.7 +/- 0.1 fmol/min/109 plts, NS). During TERT, platelet cNOS activity rose in A and B (0.6 +/- 0.1 vs. 1.8 +/- 0.1 fmol/min/109 plts, P < 0.05 and 0.7 +/- 0.1 vs. 2.4 +/- 0.2, P < 0.001, A1 vs. A2 and B1 vs. B2, respectively). However, platelet cNOS activity of A2 did not reach the values of B2 (1.8 +/- 0.1 vs. 2.4 +/- 0.2 fmol/min/109 plts, P < 0.05; A2 vs. B2, respectively). CONCLUSIONS Sequential opposed transdermal oestrogen replacement therapy was able to increase platelet cNOS activity in postmenopausal women with type 2 diabetes mellitus, suggesting that its use might be positive in preventing cardiovascular pathologies.
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26
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Mayhan WG, Sun H, Irvine SD. Influence of gender on dilatation of the basilar artery during diabetes mellitus. Brain Res 2002; 930:182-90. [PMID: 11879808 DOI: 10.1016/s0006-8993(02)02245-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The first goal of the present study was to examine the influence of gender on reactivity of the basilar artery. The second goal of this study was to examine the effect of diabetes mellitus on reactivity of the basilar artery in male and female rats. We examined in vivo responses of the basilar artery in male and female nondiabetic and diabetic rats in response to a nitric oxide synthase (NOS)-dependent (acetylcholine) and -independent (nitroglycerin) agonist. In nondiabetic male and female rats, acetylcholine and nitroglycerin produced dose-related dilatation of the basilar artery. However, the magnitude of vasodilatation in response to acetylcholine and a high concentration of nitroglycerin was significantly greater in female than in male rats. Acetylcholine (1.0 microM) dilated the basilar artery by 11 +/- 2% in nondiabetic males versus 25 +/- 4% in nondiabetic females (P<0.05). Nitroglycerin (1.0 microM) dilated the basilar artery by 37 +/- 8% in nondiabetic males versus 62 +/- 5% in nondiabetic females (P<0.05). Thus, there is a significant effect of gender on reactivity of the basilar artery during physiologic conditions. Dilatation of the basilar artery in response to acetylcholine, but not nitroglycerin, was impaired in diabetic male and female rats compared to their nondiabetic counterparts. Acetylcholine (1.0 microM) dilated the basilar artery by only 5 +/- 1% in diabetic males and by only 4 +/- 1% in diabetic females. In summary, dilatation of the basilar artery in response to NOS-dependent agonist was significantly greater in nondiabetic female than in nondiabetic male rats. In addition, diabetes mellitus impaired NOS-dependent dilatation of the basilar artery not only in male rats, but also in female rats. We suggest that the results of these studies provide insight into the pathogenesis of cerebrovascular abnormalities observed in postmenopausal women.
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Affiliation(s)
- William G Mayhan
- Department of Physiology and Biophysics, University of Nebraska Medical Center, 984575 Nebraska Medical Center, Omaha, NE 68198-4575, USA.
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27
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Pinna C, Cignarella A, Zanardo R, Bolego C, Puglisi L. Gender differences and antioxidant treatment affect aortic reactivity in short-term diabetic rats. Eur J Pharmacol 2001; 431:71-9. [PMID: 11716845 DOI: 10.1016/s0014-2999(01)01416-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Diabetes is associated with gender-specific macrovascular complications arising from increased oxidant stress in the vascular wall. In this study, male and female rats were treated with two structurally unrelated drugs sharing antioxidant properties, lercanidipine and Leucoselect (both 3 mg/kg/day), for 1 week starting 1 day after streptozotocin-diabetes induction. Concentration-response curves to L-nitroarginine methylester (L-NAME), superoxide dismutase and acetylcholine in aortic rings showed significantly greater nitric oxide-mediated relaxation in female compared with male non-diabetic rats. Diabetes increased contractility to noradrenaline and L-NAME in both genders, whereas relaxation to acetylcholine and iloprost were significantly attenuated in females only. Treatment with lercanidipine and Leucoselect restored, at least in part, responses to noradrenaline, acetylcholine and iloprost without affecting those to L-NAME and sodium nitroprusside. Unexpectedly, both drugs impaired superoxide dismutase response in female tissues. In conclusion, female rat aorta is markedly exposed to short-term diabetic vascular injury, which may be prevented by antioxidant treatment.
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Affiliation(s)
- C Pinna
- Department of Pharmacological Sciences, University of Milan, Via Balzaretti 9, 20133, Milan, Italy.
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28
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Koh KK, Kang MH, Jin DK, Lee SK, Ahn JY, Hwang HY, Yang SH, Kim DS, Ahn TH, Shin EK. Vascular effects of estrogen in type II diabetic postmenopausal women. J Am Coll Cardiol 2001; 38:1409-15. [PMID: 11691516 DOI: 10.1016/s0735-1097(01)01566-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVES We assessed the effects of estrogen on vascular dilatory and other homeostatic functions potentially affected by nitric oxide (NO)-potentiating properties in type II diabetic postmenopausal women. BACKGROUND There is a higher cardiovascular risk in diabetic women than in nondiabetic women. This would suggest that women with diabetes do not have the cardioprotection associated with estrogen. METHODS We administered placebo or conjugated equine estrogen, 0.625 mg/day for 8 weeks, to 20 type II diabetic postmenopausal women in a randomized, double-blinded, placebo-controlled, cross-over design. RESULTS Compared with placebo, estrogen tended to lower low-density lipoprotein (LDL) cholesterol levels by 15 +/- 23% (p = 0.007) and increase high-density lipoprotein (HDL) cholesterol levels by 8 +/- 16% (p = 0.034). Thus, the ratio of LDL to HDL cholesterol levels significantly decreased with estrogen, by 20 +/- 24%, as compared with placebo (p = 0.001). Compared with placebo, estrogen tended to increase triglyceride levels by 16 +/- 48% and lower glycosylated hemoglobin levels by 3 +/- 13% (p = 0.295 and p = 0.199, respectively). However, estrogen did not significantly improve the percent flow-mediated dilatory response to hyperemia (17 +/- 75% vs. placebo; p = 0.501). The statistical power to accept our observation was 81.5%. Compared with placebo, estrogen did not significantly change E-selectin, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, monocyte chemoattractant protein-1 or matrix metalloproteinase-9 levels. Compared with placebo, estrogen tended to decrease tissue factor antigen and increase tissue factor activity levels by 7 +/- 46% and 5 +/- 34%, respectively (p = 0.321 and p = 0.117, respectively) and lower plasminogen activator inhibitor-1 levels by 16 +/- 31% (p = 0.043). CONCLUSIONS The effects of estrogen on endothelial, vascular dilatory and other homeostatic functions were less apparent in type II diabetic postmenopausal women, despite the beneficial effects of estrogen on lipoprotein levels.
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Affiliation(s)
- K K Koh
- Department of Cardiology, Inchon, South Korea.
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Sanz E, Monge L, Fernández N, Martínez MA, Diéguez G, García-Villalón AL. Diabetes abolishes the gender difference in vasopressin-mediated potentiation of sympathetic vasoconstriction. Eur J Pharmacol 2001; 427:243-50. [PMID: 11567655 DOI: 10.1016/s0014-2999(01)01261-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Electrical field stimulation (4 Hz, 0.2 ms pulse duration, at a supramaximal voltage of 70 V, for 1 s) of isolated rat tail artery segments produced contraction which was lower in female than in male rats, and was reduced by streptozotocin-induced diabetes in both genders. This contraction was potentiated by vasopressin (10(-12)-10(-10) M) more in normoglycemic male than in normoglycemic female rats, and this effect of vasopressin was increased by the cyclooxigenase inhibitor meclofenamate (10(-5) M) in female control rats, but not in diabetic female, or control and diabetic male rats, and it was not modified by the nitric oxide synthase inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME, 10(-4) M). Endothelin-1 (10(-10)-3 x 10(-9) M) also potentiated the contraction to electrical stimulation. This potentiation was similar in all experimental groups, and it was not modified by meclofenamate or L-NAME. These results suggest that the potentiating effect of vasopressin, but not that of endothelin-1, on the sympathetic vasoconstriction, is lower in females than in males, probably by an increased release of vasodilating prostanoids, and this release may be reduced by diabetes in females.
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Affiliation(s)
- E Sanz
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma, Arzobispo Morcillo 2, 28029 Madrid, Spain
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30
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Pinna C, Zanardo R, Cignarella A, Bolego C, Eberini I, Nardi F, Zancan V, Puglisi L. Diabetes influences the effect of 17beta-estradiol on mechanical responses of rat urethra and detrusor strips. Life Sci 2000; 66:617-27. [PMID: 10794517 DOI: 10.1016/s0024-3205(99)00634-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Estrogen deficiency is one of the factors involved in the stress incontinence in postmenopausal women, and estrogens have been used clinically in the treatment of urinary disorders during menopause. Sex hormones seem to be also involved in the diabetic changes of urinary bladder and urethra, because ovariectomy causes an increase in the micturition of streptozotocin-diabetic rats. In the present study diabetic and healthy female rats were used to investigate the effect of 17beta-estradiol on mechanical contractions to norepinephrine and to KCI and relaxations to ATP on isolated proximal urethral preparations as well as on contractions to ACh, ATP and KCl on detrusor smooth muscle strips. The data were compared with those obtained in OVX animals, with or without estradiol replacement. The present study showed that ovariectomy decreased the responses to ATP, NE and KCl in urethral preparations, and responses to ATP, ACh and KCl in bladder strips from both healthy and diabetic rats. Diabetes appeared to potentiate the effect of ovariectomy in both tissues. Estrogen replacement was able to recover functional responses in urethras of healthy rats. In diabetic rats, this treatment partially restored ATP-induced responses in both tissues, almost completely restored those to NE in urethra and those to ACh in bladder. This study clearly indicated that abnormalities of urethra and bladder function caused by ovariectomy can be restored by estrogen treatment also in diabetic animals, at least at an early stage of disease.
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Affiliation(s)
- C Pinna
- Institute of Pharmacological Sciences, University of Milan, Italy
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