Omega-3E treatment regulates matrix metalloproteinases and prevents vascular reactivity alterations in diabetic rat aortaThis article is one of a selection of papers published in a special issue on Advances in Cardiovascular Research.

2009 ◽  
Vol 87 (12) ◽  
pp. 1063-1073 ◽  
Author(s):  
Esma N. Zeydanli ◽  
Belma Turan

It is known that increased generation of oxidants and (or) reduced endogenous antioxidant defense mechanisms are associated with the etiology of diabetic vascular complications. Although a close correlation exists between increased oxidative stress and the activation of matrix metalloproteinases (MMPs), little is known about the effect of hyperglycemia on the regulation and contribution of MMPs in the vascular system. Therefore, we aimed to examine whether omega-3E (50 mg/kg per day for 4 weeks), a long-chain (n-3) polyunsaturated fatty acid enriched with vitamin E, has a beneficial effect on vascular dysfunction via affecting MMPs in streptozotocin-diabetic rat aorta. Omega-3E treatment improved the diabetes-induced impairment of phenylephrine-induced contraction and isoproterenol-induced relaxation responses of aorta. It also exhibited marked protection against diabetes-induced degenerative changes in smooth muscle cell morphology. Biochemical data showed that this treatment significantly prevented important changes, such as inhibition of MMP-2 and MMP-9 activity, loss of tissue inhibitor of matrix metalloproteinase-4 (TIMP-4) protein, increase in tissue levels of thiol oxidation, endothelin-1, protein kinase C (PKC), and cAMP production, and decrease in tissue level of nitrite. These results indicated that omega-3E significantly improved impaired vascular responses and regulated the activity of MMPs via preventing oxidative injury. Overall, the data suggest that omega-3E ameliorates or prevents vascular reactivity alterations in diabetes. Such an observation provides preliminary evidence for omega-3E’s potential as a therapeutic agent for the prevention of vascular disorders in diabetes.

2018 ◽  
Vol 96 (8) ◽  
pp. 757-764 ◽  
Author(s):  
M. Bilgehan Pektas ◽  
Ozge Turan ◽  
Gozde Ozturk Bingol ◽  
Esra Sumlu ◽  
Gökhan Sadi ◽  
...  

Transient elevations in blood glucose level may lead to changes in vascular function. Herein, we investigated the effects of high-glucose or high-fructose challenge, as well as potential influence of juglone or resveratrol on vascular reactivity, Akt/eNOS, and insulin signaling effectors in rat aorta. Aortic segments of rats were incubated with high glucose (30 mmol/L) or high fructose (2 mmol/L) in the absence and presence of juglone (5 μmol/L) or resveratrol (10 μmol/L). Acute high-glucose incubation markedly decreased acetylcholine-induced relaxation, which is further inhibited by juglone, but ameliorated by resveratrol. Incubation with high glucose caused significant reduction in pAkt/total Akt and peNOS/total eNOS ratios, as well as in the expression of some genes involved in insulin signaling. Juglone produced a further impairment, whereas resveratrol resulted in an improvement on the expression profiles of these proteins and genes. Acute exposure of aortic segments to high glucose causes a reduction in acetylcholine-induced relaxation in association with suppression of Akt/eNOS pathway, as well as several genes in insulin signaling pathway. Juglone and resveratrol have opposite actions on vascular relaxation and the above signaling targets. These findings could be relevant for the treatment of hyperglycemia-induced vascular complications.


2016 ◽  
Vol 2016 ◽  
pp. 1-10
Author(s):  
P. P. Wołkow ◽  
B. Bujak-Giżycka ◽  
J. Jawień ◽  
R. Olszanecki ◽  
J. Madej ◽  
...  

Purpose. Products of angiotensin (ANG) I metabolism may predispose to vascular complications of diabetes mellitus. Methods. Diabetes was induced with streptozotocin (75 mg/kg i.p.). Rat aorta fragments, isolated 4 weeks later, were pretreated with perindoprilat (3 μM), thiorphan (3 μM), or vehicle and incubated for 15 minutes with ANG I (1 μM). Products of ANG I metabolism through classical (ANG II, ANG III, and ANG IV) and alternative (ANG (1–9), ANG (1–7), and ANG (1–5)) pathways were measured in the buffer, using liquid chromatography-mass spectrometry. Results. Incubation with ANG I resulted in higher concentration of ANG II (P = 0.02, vehicle pretreatment) and lower of ANG (1–9) (P=0.048, perindoprilat pretreatment) in diabetes. Preference for the classical pathway is suggested by higher ANG III/ANG (1–7) ratios in vehicle (P=0.03), perindoprilat (P=0.02), and thiorphan pretreated (P=0.02) diabetic rat. Within the classical pathway, ratios of ANG IV/ANG II (P=0.01) and of ANG IV/ANG III (P=0.049), but not of ANG III/ANG II are lower in diabetes. Conclusions. Diabetes in rats led to preference toward deleterious (ANG II, ANG III) over protective (ANG IV, ANG (1–9), and ANG (1–7)) ANG I metabolites.


2011 ◽  
Vol 301 (3) ◽  
pp. H1135-H1142 ◽  
Author(s):  
Vahagn A. Ohanyan ◽  
Giacinta Guarini ◽  
Charles K. Thodeti ◽  
Phani K. Talasila ◽  
Priya Raman ◽  
...  

Transient receptor potential vanilliod 1 (TRPV1) channels have recently been postulated to play a role in the vascular complications/consequences associated with diabetes despite the fact that the mechanisms through which TRPV1 regulates vascular function are not fully known. Accordingly, our goal was to define the mechanisms by which TRPV1 channels modulate vascular function and contribute to vascular dysfunction in diabetes. We subjected mice lacking TRPV1 [TRPV1(−/−)], db/ db, and control C57BLKS/J mice to in vivo infusion of the TRPV1 agonist capsaicin or the α-adrenergic agonist phenylephrine (PE) to examine the integrated circulatory actions of TRPV1. Capsaicin (1, 10, 20, and 100 μg/kg) dose dependently increased MAP in control mice (5.7 ± 1.6, 11.7 ± 2.1, 25.4 ± 3.4, and 51.6 ± 3.9%), which was attenuated in db/db mice (3.4 ± 2.1, 3.9 ± 2.1, 7.0 ± 3.3, and 17.9 ± 6.2%). TRPV1(−/−) mice exhibited no changes in MAP in response to capsaicin, suggesting the actions of this agonist are specific to TRPV1 activation. Immunoblot analysis revealed decreased aortic TRPV1 protein expression in db/db compared with control mice. Capsaicin-induced responses were recorded following inhibition of endothelin A and B receptors (ETA /ETB). Inhibition of ETA receptors abolished the capsaicin-mediated increases in MAP. Combined antagonism of ETA and ETB receptors did not further inhibit the capsaicin response. Cultured endothelial cell exposure to capsaicin increased endothelin production as shown by an endothelin ELISA assay, which was attenuated by inhibition of TRPV1 or endothelin-converting enzyme. TRPV1 channels contribute to the regulation of vascular reactivity and MAP via production of endothelin and subsequent activation of vascular ETA receptors. Impairment of TRPV1 channel function may contribute to vascular dysfunction in diabetes.


Antioxidants ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 761 ◽  
Author(s):  
Yue Ruan ◽  
Subao Jiang ◽  
Aytan Musayeva ◽  
Adrian Gericke

Many retinal diseases, such as diabetic retinopathy, glaucoma, and age-related macular (AMD) degeneration, are associated with elevated reactive oxygen species (ROS) levels. ROS are important intracellular signaling molecules that regulate numerous physiological actions, including vascular reactivity and neuron function. However, excessive ROS formation has been linked to vascular endothelial dysfunction, neuron degeneration, and inflammation in the retina. ROS can directly modify cellular molecules and impair their function. Moreover, ROS can stimulate the production of inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) causing inflammation and cell death. However, there are various compounds with direct or indirect antioxidant activity that have been used to reduce ROS accumulation in animal models and humans. In this review, we report on the physiological and pathophysiological role of ROS in the retina with a special focus on the vascular system. Moreover, we present therapeutic approaches for individual retinal diseases targeting retinal signaling pathways involving ROS.


2004 ◽  
Vol 287 (1) ◽  
pp. H135-H148 ◽  
Author(s):  
Tsuneo Kobayashi ◽  
Takayuki Matsumoto ◽  
Kazuyuki Ooishi ◽  
Katsuo Kamata

The aim of the present study was to compare vascular dysfunction between the early (12 wk old) and later (36 wk old) stages of spontaneous diabetes in Goto-Kakizaki (GK) rats. We also evaluated the aortic expression of the α2D-adrenoceptor and endothelial nitric oxide synthase (eNOS). Vascular reactivity was assessed in thoracic aortas from age-matched control rats and 12- and 36-wk GK rats. Using RT-PCR and immunoblots, we also examined the changes in expression of the α2D-adrenoceptor and eNOS. In aortas from GK rats (vs. those from age-matched control rats): 1) the relaxation response to ACh was enhanced at 12 wk but decreased at 36 wk; 2) the relaxation response to sodium nitroprusside was decreased at both 12 and 36 wk, 3) norepinephrine (NE)-induced contractility was decreased at 12 wk but not at 36 wk, 4) the expressions of α1B- and α1D-adrenoceptors were unaffected, whereas those of α2D-adrenoceptor and eNOS mRNAs were increased at both 12 and 36 wk; and 5) NE- and ACh-stimulated NOx (nitrite and nitrate) levels were increased at 12 wk, although at 36 wk ACh-stimulated NOx was lower, whereas NE-stimulated NOx showed no change. These results clearly demonstrate that enhanced ACh-induced relaxation and impaired NE-induced contraction, due to NO overproduction via eNOS and increased α2D-adrenoceptor expression, occur in early-stage GK rats and that the impaired ACh-induced relaxation in later-stage GK rats is due to reductions in both NO production and NO responsiveness (but not in eNOS expression).


2017 ◽  
Vol 312 (6) ◽  
pp. F971-F981 ◽  
Author(s):  
Fan Fan ◽  
Mallikarjuna R. Pabbidi ◽  
Ying Ge ◽  
Longyang Li ◽  
Shaoxun Wang ◽  
...  

We have reported that the myogenic response of the renal afferent arteriole (Af-art) and middle cerebral artery (MCA) and autoregulation of renal and cerebral blood flow are impaired in Fawn-Hooded Hypertensive (FHH) rats. Transfer of a region of chromosome 1 containing γ-adducin (Add3) from the Brown Norway rat rescued the vascular dysfunction and the development of renal disease. To examine whether Add3 is a viable candidate gene altering renal and cerebral hemodynamics in FHH rats, we knocked down the expression of Add3 in rat Af-arts and MCAs cultured for 36-h using a 27-mer Dicer-substrate short interfering RNA (DsiRNA). Control Af-arts constricted by 10 ± 1% in response to an elevation in pressure from 60 to 120 mmHg but dilated by 4 ± 3% when treated with Add3 DsiRNA. Add3 DsiRNA had no effect on the vasoconstrictor response of the Af-art to norepinephrine (10−7 M). Add3 DsiRNA had a similar effect on the attenuation of the myogenic response in the MCA. Peak potassium currents were threefold higher in smooth muscle cells isolated from Af-arts or MCAs transfected with Add3 DsiRNA than in nontransfected cells isolated from the same vessels. This is the first study demonstrating that Add3 plays a role in the regulation of potassium channel function and vascular reactivity. It supports the hypothesis that sequence variants in Add3, which we previously identified in FHH rats, may play a causal role in the impaired myogenic response and autoregulation in the renal and cerebral circulation.


2007 ◽  
Vol 4 (2) ◽  
pp. 348-363 ◽  
Author(s):  
Christopher Wingard ◽  
David Fulton ◽  
Shahid Husain

Hypertension ◽  
2012 ◽  
Vol 60 (suppl_1) ◽  
Author(s):  
Allan K Alencar ◽  
Sharlene L Pereira ◽  
Arthur E Kummerle ◽  
Sharon S Langraf ◽  
Celso Caruso-Neves ◽  
...  

Pulmonary arterial hypertension (PAH) is characterized by enhanced pulmonary vascular resistance with subsequent remodeling and right ventricular hypertrophy. Vascular reactivity and ventricular function were investigated in rats with monocrotaline-induced PAH and treated with a new N-acylhydrazone derivative named as LASSBio-1359. METHODS: Protocols were approved by Animal Care and Use Committee at Universidade Federal do Rio de Janeiro. Male Wistar rats received a single i.p. injection of monocrotaline (MCT) (60 mg/kg) for PAH induction and were randomly divided in groups which were treated with: saline, vehicle and LASSBio-1359 (50 mg/kg p.o.). After 14 days of treatment, some parameters were evaluated: pulmonary acceleration time (PAT); right ventricular systolic pressure (RVSP); vascular reactivity to acetylcholine; expression of iNOS in pulmonary tissue; wall thickness of pulmonary artery (PAWT). Results: PAT (ms) was increased from 26.2 ± 2.8 to 41.3 ± 3.9 in PAH group treated with vehicle (n=8, p<0.05) and was reduced to 24.2 ± 1.7 when PAH group was treated with LASSBio-1359. RVSP (mmHg) increased from 26.0 ± 2.0 to 55.2 ± 2.3 in PAH group (p<0.05) but was similar to control after treatment with LASSBio-1359 (31.8 ± 2.3 mm Hg). Ratio of right ventricle and body weight (mg/g) was 0.66 ± 0.02, 1.63 ± 0.16 and 0.87 ± 0.10 for control, vehicle- and LASSBio-1359-treated PAH groups, respectively. PAH promoted ventricular dysfunction which was reduced by LASSBio-1359. The pulmonary artery maximum relaxation (%) was 57.3 ± 5.5, 43.6 ± 1.2 and 61.4 ± 8.4 for control, vehicle and LASSBio-1359-treated groups indicating that PAH promoted endothelium injury which was recovered by LASSBio-1359. iNOS expression in pulmonary tissue was increased from 0.48 ± 1.31 to 0.98 ± 3.14 in PAH group and reduced to 0.53 ± 1.83 in rats treated with LASSBio-1359. The PAWT (%) were increased from 74.1 ± 1.3 to 90.2 ± 2.7 in PAH group (p<0.05) but was 74.4 ± 1.3 when treated with LASSBio-1359. This compound showed an in vitro vasodilatory activity mediated by activation of adenosinergic A2A receptor. Conclusion: LASSBio-1359 reduced ventricular and vascular dysfunction in monocrotaline-induced PAH in rats indicating a possible new alternative to treat PAH.


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