scholarly journals Unacylated Ghrelin Improves Vascular Dysfunction and Attenuates Atherosclerosis during High-Fat Diet Consumption in Rodents

2019 ◽  
Vol 20 (3) ◽  
pp. 499 ◽  
Author(s):  
Michela Zanetti ◽  
Gianluca Gortan Cappellari ◽  
Andrea Graziani ◽  
Rocco Barazzoni

Unacylated ghrelin (UnGhr) exerts several beneficial actions on vascular function. The aim of this study was to assess the effects of UnGhr on high-fat induced endothelial dysfunction and its underlying mechanisms. Thoracic aortas from transgenic mice, which were overexpressing UnGhr and being control fed either a standard control diet (CD) or a high-fat diet (HFD) for 16 weeks, were harvested and used for the assessment of vascular reactivity, endothelial nitric oxide synthase (eNOS) expression and activity, thiobarbituric acid reactive substances (TBARS) and glutathione levels, and aortic lipid accumulation by Oil Red O staining. Relaxations due to acetylcholine and to DEA-NONOate were reduced (p < 0.05) in the HFD control aortas compared to vessels from the CD animals. Overexpression of UnGhr prevented HFD-induced vascular dysfunction, while eNOS expression and activity were similar in all vessels. HFD-induced vascular oxidative stress was demonstrated by increased (p < 0.05) aortic TBARS and glutathione in wild type (Wt) mice; however, this was not seen in UnGhr mice. Moreover, increased (p < 0.05) HFD-induced lipid accumulation in vessels from Wt mice was prevented by UnGhr overexpression. In conclusion, chronic UnGhr overexpression results in improved vascular function and reduced plaque formation through decreased vascular oxidative stress, without affecting the eNOS pathway. This research may provide new insight into the mechanisms underlying the beneficial effects of UnGhr on the vascular dysfunction associated with obesity and the metabolic syndrome.

2009 ◽  
Vol 118 (4) ◽  
pp. 291-301 ◽  
Author(s):  
Ahmed A. Elmarakby ◽  
John D. Imig

Obesity and hypertension are the two major risk factors that contribute to the progression of end-stage renal disease. To examine whether hypertension further exacerbates oxidative stress and vascular dysfunction and inflammation in obese rats, four groups of male Sprague–Dawley rats were fed either a normal (7% fat) or high-fat (36% fat) diet for 6 weeks and osmotic pumps were implanted to deliver ANG (angiotensin II) or vehicle for an additional 4 weeks. Treatment with the high-fat diet did not alter ANG-induced hypertension compared with the normal diet (174±6 compared with 170±5 mmHg respectively). Treatment with the high-fat diet increased body weight gain and plasma leptin levels and induced insulin resistance in normotensive and ANG-induced hypertensive rats. Plasma TBARS (thiobarbituric acid-reacting substances), a measure of oxidative stress, were elevated in high-fat diet-fed rats compared with controls (11.2±1 compared with 8.4±1 nmol/ml respectively) and was increased further in ANG-induced hypertensive rats fed a high-fat diet (18.8±2.2 nmol/ml). Urinary nitrite excretion was also decreased in rats fed a high-fat diet without or with ANG infusion compared with controls. Afferent arteriolar relaxation to acetylcholine was impaired in rats fed the high-fat diet without or with ANG infusion. Renal cortical TNF-α (tumour necrosis factor-α), COX-2 (cyclo-oxygenase-2) and phospho-IKK (inhibitor of nuclear factor κB kinase) expression increased in high-fat diet-fed rats compared with normal diet-fed rats. The increases in phospho-IKK and COX-2 expression were elevated further in ANG-induced hypertensive rats fed the high-fat diet. These results suggest that ANG-induced hypertension exacerbates oxidative stress and renal inflammation without further impairment in vascular dysfunction in high-fat diet-induced obesity.


2012 ◽  
Vol 40 (06) ◽  
pp. 1217-1228 ◽  
Author(s):  
Woojung Lee ◽  
Dae-Woon Eom ◽  
Yujung Jung ◽  
Noriko Yamabe ◽  
Seungyong Lee ◽  
...  

Obesity is an important and preventable risk factor for renal disease. The administration of an antioxidant with a lipid-lowering effect is an important therapeutic approach for kidney disease in obese patients. The present study was conducted to examine whether methanolic extract of Dendrobium moniliforme (DM), one of the most famous traditional medicines used in many parts of the world, has an antioxidant effect in vitro and an ameliorative effect on high-fat diet (HFD)-induced alterations such as renal dysfunction and lipid accumulation in vivo. The 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity of DM extract (IC50 = 29.6 μg/mL) was increased in a dose-dependent manner. The LLC-PK1 kidney cell damage induced by oxidative stress was significantly inhibited by the treatments with DM extract. In the animal study, DM extract (200 mg/kg) was orally administered every day for nine weeks to HFD-fed mice, and its effect was compared with that of metformin. The administration of DM extract decreased the elevated serum glucose, total cholesterol concentration and renal lipid accumulation in HFD-fed mice. It also ameliorated renal dysfunction biomarkers including serum creatinine and renal collagen IV deposition. Taken together, these results provide important evidence that DM extract exhibits a pleiotropic effect on obesity induced parameters and exerted a renoprotective effect in HFD-fed mice.


Hypertension ◽  
2012 ◽  
Vol 60 (suppl_1) ◽  
Author(s):  
Jian Cao ◽  
Stephen J Peterson ◽  
Michal L Schwartzman ◽  
Komal Sodhi ◽  
Rita Rezzani ◽  
...  

The principal goal of the present study is to examine the contributions of adipocyte specific over expression of the cytoprotective gene heme oxygenase-1 (HO-1) in modulating vascular function in an animal model of diet induced obesity. A lentiviral construct of the human HO-1 was synthesized under the control of an aP2-activated promoter so as to ensure HO-1 targeting to murine adipocytes. Lentiviruses (50 μl, 2x109 TU/ml in saline) were injected into the C57BL/6 mice by a single intracardiac injection. Mice (6-7 wks old) were divided into 4 groups: Control, high fat diet (HF) mice receiving the control Lenti-aP2-GFP (HF-GFP) and high fat diet mice receiving the lenti-aP2-HO-1 (HF-HO-1) with and without treatment with SnMP. Transduction of lenti-aP2-HO-1 increased human HO-1 expression in adipose tissues without affecting endogenous mice HO-1 (p<0.01). In mice fed a HF diet, lenti-aP2-HO-1 transduction attenuated the increases in body weight (from 52.0±1.0 g to 35.6±2.1g; p<0.01), blood glucose (from 255±3.5 g to 140±2.9mg/dl), blood pressure (from 135±2.8mmHg to 101±2.2mmHg; p<0.01) and inflammatory cytokines as well as the content of both visceral (from 5.5±0.15g to 2.9±0.22g; p<0.05) and subcutaneous fat (p<0.05). Transduction of lenti-aP2-HO-1 increased the numbers of adipocytes of small cell size (p<0.05), insulin sensitivity (p<0.05), adiponectin levels (from 32.4±1.9μg/ml to 19.9±2.1μg/ml; p<0.05) as well as vascular relaxation to acetylcholine ( p<0.05) compared to HF mice administered the lenti-aP2- GFP. Adipocytes of mice fed a HF diet expressed high levels of PPARγ, aP2, C/EBP and Wnt5b proteins and displayed marked increases in Peg1/Mest (p<0.03). Lenti-aP2-HO-1 transduction lowered the elevated levels of these proteins and increased Shh, Wnt10b and β-catenin (p<0.05). Inhibition of HO activity by administration of tin mesoporphyrin (SnMP) to HF-fed mice transduced with the lenti-aP2-HO-1 reversed the decrease in Peg 1/Mest, TNFα and MCP-1 levels. This novel study demonstrate that adipocyte-specific overexpression of HO-1 attenuates HF-mediated adiposity and vascular dysfunction, increases insulin sensitivity and improves adipocyte function by increasing adiponectin, Shh and WNT10b and decreasing inflammatory cytokines.


Nutrients ◽  
2015 ◽  
Vol 7 (10) ◽  
pp. 8491-8502 ◽  
Author(s):  
Jiqu Xu ◽  
Xiaoli Liu ◽  
Hui Gao ◽  
Chang Chen ◽  
Qianchun Deng ◽  
...  

Author(s):  
Kristen Nowak ◽  
Heather Farmer-Bailey ◽  
Wei Wang ◽  
Zhiying You ◽  
Cortney Steele ◽  
...  

Background and Objectives: Clinical manifestations of autosomal dominant polycystic kidney disease (ADPKD), including evidence of vascular dysfunction, can begin in childhood. Curcumin is a polyphenol found in turmeric that reduces vascular dysfunction in rodent models and humans without ADPKD. It also slows kidney cystic progression in a murine model of ADPKD. We hypothesized that oral curcumin therapy would reduce vascular endothelial dysfunction and arterial stiffness in children/young adults with ADPKD. Design, Setting, Participants, and Measurements: In a randomized, placebo-controlled, double-blind trial, 68 children/ young adults 6-25 years of age with ADPKD and an estimated glomerular filtration rate >80 mL/min/1.73 m2 were randomized to either curcumin supplementation (25 mg/kg body weight/day) or placebo, administered in powder form for 12 months. The co-primary outcomes were brachial artery flow-mediated dilation [FMDBA] and aortic pulse-wave velocity [aPWV]. We also assessed change in circulating/urine biomarkers of oxidative stress/inflammation and kidney growth (height-adjusted total kidney volume]) by magnetic resonance imaging. In a sub-group of participants ≥18 years, vascular oxidative stress was measured as the change in FMDBA following an acute infusion of ascorbic acid. Results: Enrolled participants were 18±5 [mean±s.d.] years; 54% female; baseline FMDBA was 9.3±4.1 % change, and baseline aPWV was 512±94 cm/sec. Fifty-seven participants completed the trial. Neither co-primary endpoint changed with curcumin (estimated change [95% confidence interval] for FMDBA (% change): curcumin: 1.14 [-0.84, 3.13]; placebo: 0.33 [-1.34, 2.00]; estimated difference for change: 0.81 [-1.21, 2.84], p=0.48; aPWV (cm/sec: curcumin: 0.6 [-25.7, 26.9]; placebo: 6.5 [-20.4, 33.5]; estimated difference for change: -5.9 [-35.8, 24.0], p=0.67) (intent to treat). There was no curcumin-specific reduction in vascular oxidative stress, nor changes in mechanistic biomarkers. Height-adjusted total kidney volume also did not change as compared to placebo. Conclusions: Curcumin supplementation does not improve vascular function or slow kidney growth in children/young adults with ADPKD.


2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
Weixia Sun ◽  
Zhiguo Zhang ◽  
Qiang Chen ◽  
Xia Yin ◽  
Yaowen Fu ◽  
...  

Magnoliaas an herbal material obtained fromMagnolia officinalishas been found to play an important role in anti-inflammation, antioxidative stress, and antiapoptosis. This study was designed to investigate the effect ofMagnoliaextract (BL153) on obesity-associated lipid accumulation, inflammation, oxidative stress, and apoptosis in the heart. C57BL/6 mice were fed a low- (10 kcal% fat) or high-fat (60 kcal% fat) diet for 24 weeks to induce obesity. These mice fed with high-fat diet (HFD) were given a gavage of vehicle, 2.5, 5, or 10 mg/kg body weight BL153 daily. The three doses of BL153 treatment slightly ameliorated insulin resistance without decrease of body weight gain induced by HFD feeding. BL153 at 10 mg/kg slightly attenuated a mild cardiac hypertrophy and dysfunction induced by HFD feeding. Both 5 mg/kg and 10 mg/kg of BL153 treatment significantly inhibited cardiac lipid accumulation measured by Oil Red O staining and improved cardiac inflammation and oxidative stress by downregulating ICAM-1, TNF-α, PAI-1, 3-NT, and 4-HNE. TUNEL staining showed that BL153 treatment also ameliorated apoptosis induced by mitochondrial caspase-3 independent cell death pathway. This study demonstrates that BL153 attenuates HFD-associated cardiac damage through prevention of HFD-induced cardiac lipid accumulation, inflammation, oxidative stress, and apoptosis.


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