Abstract 17579: Quantification of Femoral Adipose Tissue Provides Novel Mechanistic Insights Into the "Obesity Paradox": a Translational Approach

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Alexios S Antonopoulos ◽  
Marios Margaritis ◽  
Laura Herdman ◽  
Patricia Coutinho ◽  
Constantinos Psarros ◽  
...  

Introduction: Obesity has been paradoxically associated with a better outcome of CAD patients, while anthropometic measures of obesity provide limited information on adipose tissue (AT) biology. We hypothesised that quantification of femoral AT (FemAT) deposition using U/S can provide mechanistic insights into the obesity paradox. Methods: FemAT biopsies from 185 pts undergoing coronary bypass surgery (CABG) were cultured ex vivo for secretome and gene expression studies. FemAT thickness was measured by U/S at both the anterior and exterior surface of the thigh, at the mid point of the distance between the iliac crest and the knee, and the average of both thighs was calculated. Malondialdehyde (MDA), a marker of oxidative stress, was measured in plasma and FemAT culture supernatants. Brachial artery (BA) flow mediated dilatation (FMD) and distensibility were assessed by U/S. Results: FemAT thickness was only weakly correlated with BMI (r=0.235, p<0.001) and waist-to-hip ratio (WHR, r=-0.179, p<0.05), suggesting that it provides different information to classic anthropometrics in obesity. Patients with increased FemAT thickness had lower plasma MDA (A), better FMD (B) and greater BA distensibility (C), despite of being more obese. On the contrary BMI did not predict systemic oxidative stress or vascular function, while WHR was weakly correlated only with FMD (rho=-0.156, p<0.05). Increased FemAT thickness was associated with lower MDA release from FemAT culture supernatants (D), and lower IL6-receptor (E) / CD68 (F) expression in FemAT samples, suggesting lower endogenous oxidative stress, and less macrophages’ infiltration. Conclusions: Femoral fat accumulation is associated with lower local AT inflammation and favourable systemic effects on vascular function in CAD. Combining imaging with AT biology could help to better understand the role of obesity-related vascular disease and provide an explanation to the “obesity paradox”.

2020 ◽  
Vol 98 (2) ◽  
pp. 85-92 ◽  
Author(s):  
Mihaela Ionica ◽  
Oana M. Aburel ◽  
Adrian Vaduva ◽  
Alexandra Petrus ◽  
Sonia Rațiu ◽  
...  

Obesity is an age-independent, lifestyle-triggered, pandemic disease associated with both endothelial and visceral adipose tissue (VAT) dysfunction leading to cardiometabolic complications mediated via increased oxidative stress and persistent chronic inflammation. The purpose of the present study was to assess the oxidative stress in VAT and vascular samples and the effect of in vitro administration of vitamin D. VAT and mesenteric artery branches were harvested during abdominal surgery performed on patients referred for general surgery (n = 30) that were randomized into two subgroups: nonobese and obese. Serum levels of C-reactive protein (CRP) and vitamin D were measured. Tissue samples were treated or not with the active form of vitamin D: 1,25(OH)2D3 (100 nmol/L, 12 h). The main findings are that in obese patients, (i) a low vitamin D status was associated with increased inflammatory markers and reactive oxygen species generation in VAT and vascular samples and (ii) in vitro incubation with vitamin D alleviated oxidative stress in VAT and vascular preparations and also improved the vascular function. We report here that the serum level of vitamin D is inversely correlated with the magnitude of oxidative stress in the adipose tissue. Ex vivo treatment with active vitamin D mitigated obesity-related oxidative stress.


Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4210
Author(s):  
Yan Zhou ◽  
Chunxiu Zhou ◽  
Xutao Zhang ◽  
Chi Teng Vong ◽  
Yitao Wang ◽  
...  

Coptisine is the major bioactive protoberberine alkaloid found in Rhizoma Coptidis. Coptisine reduces inflammatory responses and improves glucose tolerance; nevertheless, whether coptisine has vasoprotective effect in diabetes is not fully characterized. Conduit arteries including aortas and carotid arteries were obtained from male C57BL/6J mice for ex vivo treatment with risk factors (high glucose or tunicamycin) and coptisine. Some arterial rings were obtained from diabetic mice, which were induced by high-fat diet (45% kcal% fat) feeding for 6 weeks combined with a low-dose intraperitoneal injection of streptozotocin (120 mg/kg). Functional studies showed that coptisine protected endothelium-dependent relaxation in aortas against risk factors and from diabetic mice. Coptisine increased phosphorylations of AMPK and eNOS and downregulated the endoplasmic reticulum (ER) stress markers as determined by Western blotting. Coptisine elevates NO bioavailability and decreases reactive oxygen species level. The results indicate that coptisine improves vascular function in diabetes through suppression of ER stress and oxidative stress, implying the therapeutic potential of coptisine to treat diabetic vasculopathy.


Antioxidants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 503
Author(s):  
Fuka Tabata ◽  
Yasuaki Wada ◽  
Satomi Kawakami ◽  
Kazuhiro Miyaji

Serum albumin is the most abundant circulating protein in mammals including humans. It has three isoforms according to the redox state of the free cysteine residue at position 34, named as mercaptalbumin (reduced albumin), non-mercaptalbumin-1 and -2 (oxidized albumin), respectively. The serum albumin redox state has long been viewed as a biomarker of systemic oxidative stress, as the redox state shifts to a more oxidized state in response to the severity of the pathological condition in various diseases such as liver diseases and renal failures. However, recent ex vivo studies revealed oxidized albumin per se could aggravate the pathological conditions. Furthermore, the possibility of the serum albumin redox state as a sensitive protein nutrition biomarker has also been demonstrated in a series of animal studies. A paradigm shift is thus ongoing in the research field of the serum albumin. This article provides an updated overview of analytical techniques for serum albumin redox state and its association with human health, focusing on recent findings.


Antioxidants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 622
Author(s):  
Pamela A. Nono Nankam ◽  
Télesphore B. Nguelefack ◽  
Julia H. Goedecke ◽  
Matthias Blüher

Adipose tissue (AT) storage capacity is central in the maintenance of whole-body homeostasis, especially in obesity states. However, sustained nutrients overflow may dysregulate this function resulting in adipocytes hypertrophy, AT hypoxia, inflammation and oxidative stress. Systemic inflammation may also contribute to the disruption of AT redox equilibrium. AT and systemic oxidative stress have been involved in the development of obesity-associated insulin resistance (IR) and type 2 diabetes (T2D) through several mechanisms. Interestingly, fat accumulation, body fat distribution and the degree of how adiposity translates into cardio-metabolic diseases differ between ethnicities. Populations of African ancestry have a higher prevalence of obesity and higher T2D risk than populations of European ancestry, mainly driven by higher rates among African women. Considering the reported ethnic-specific differences in AT distribution and function and higher levels of systemic oxidative stress markers, oxidative stress is a potential contributor to the higher susceptibility for metabolic diseases in African women. This review summarizes existing evidence supporting this hypothesis while acknowledging a lack of data on AT oxidative stress in relation to IR in Africans, and the potential influence of other ethnicity-related modulators (e.g., genetic-environment interplay, socioeconomic factors) for consideration in future studies with different ethnicities.


2019 ◽  
Vol 317 (6) ◽  
pp. H1292-H1300 ◽  
Author(s):  
Young-Rae Kim ◽  
Julia S. Jacobs ◽  
Qiuxia Li ◽  
Ravinder Reddy Gaddam ◽  
Ajit Vikram ◽  
...  

SUMOylation is a posttranslational modification of lysine residues. Modification of proteins by small ubiquitin-like modifiers (SUMO)1, -2, and -3 can achieve varied, and often unique, physiological and pathological effects. We looked for SUMO2-specific effects on vascular endothelial function. SUMO2 expression was upregulated in the aortic endothelium of hypercholesterolemic low-density lipoprotein receptor-deficient mice and was responsible for impairment of endothelium-dependent vasorelaxation in these mice. Moreover, overexpression of SUMO2 in aortas ex vivo, in cultured endothelial cells, and transgenically in the endothelium of mice increased vascular oxidative stress and impaired endothelium-dependent vasorelaxation. Conversely, inhibition of SUMO2 impaired physiological endothelium-dependent vasorelaxation in normocholesterolemic mice. These findings indicate that while endogenous SUMO2 is important in maintenance of normal endothelium-dependent vascular function, its upregulation impairs vascular homeostasis and contributes to hypercholesterolemia-induced endothelial dysfunction. NEW & NOTEWORTHY Sumoylation is known to impair vascular function; however, the role of specific SUMOs in the regulation of vascular function is not known. Using multiple complementary approaches, we show that hyper-SUMO2ylation impairs vascular endothelial function and increases vascular oxidative stress, whereas endogenous SUMO2 is essential for maintenance of normal physiological function of the vascular endothelium.


2007 ◽  
Vol 293 (1) ◽  
pp. F371-F381 ◽  
Author(s):  
Elena Daghini ◽  
Xiang-Yang Zhu ◽  
Daniele Versari ◽  
Michael D. Bentley ◽  
Claudio Napoli ◽  
...  

The effects of chronic supplementation with antioxidant vitamins on angiogenesis are controversial. The aim of the present study was to evaluate in kidneys of normal pigs the effect of chronic supplementation with vitamins E and C, at doses that are effective in reducing oxidative stress and attenuating angiogenesis under pathological conditions. Domestic pigs were randomized to receive a 12-wk normal diet without ( n = 6) or with antioxidant vitamins supplementation (1g/day vitamin C, 100 IU·kg−1·day−1 vitamin E; n = 6). Electron beam computed tomography (CT) was used to evaluate renal cortical vascular function in vivo, and micro-CT was to assess the spatial density and average diameter of cortical microvessels (diameter <500 μm) ex vivo. Oxidative stress and expressions of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor (HIF)-1α were evaluated in renal tissue. The effects of increasing concentrations of the same vitamins on redox status and angiogenesis were also evaluated in human umbilical vascular endothelial cells (HUVEC). Compared with normal pigs, the density of cortical transmural microvessels was significantly greater in vitamin-supplemented pigs (149.0 ± 11.7 vs. 333.8 ± 48.1 vessel/cm2, P < 0.05), whereas the cortical perfusion response to ACh was impaired. This was accompanied by a significant increase in tissue oxidative stress and levels of VEGF and HIF-1α. A low dose of antioxidant decreased, whereas a high dose increased, HUVEC oxidative stress and angiogenesis, which was partly mediated by hydrogen peroxide. Antioxidant vitamin supplementation can increase tissue oxidative redox and microvascular proliferation in the normal kidney, probably due to a biphasic effect that depends on basal redox balance.


2008 ◽  
Vol 22 (9) ◽  
pp. 2176-2189 ◽  
Author(s):  
Yun Sok Lee ◽  
A Young Kim ◽  
Jin Woo Choi ◽  
Min Kim ◽  
Shintaro Yasue ◽  
...  

Abstract Glutathione peroxidase 3 (GPx3) accounts for the major antioxidant activity in the plasma. Here, we demonstrate that down-regulation of GPx3 in the plasma of obese subjects is associated with adipose GPx3 dysregulation, resulting from the increase of inflammatory signals and oxidative stress. Although GPx3 was abundantly expressed in kidney, lung, and adipose tissue, we observed that GPx3 expression was reduced selectively in the adipose tissue of several obese animal models as decreasing plasma GPx3 level. Adipose GPx3 expression was greatly suppressed by prooxidative conditions such as high levels of TNFα and hypoxia. In contrast, the antioxidant N-acetyl cysteine and the antidiabetic drug rosiglitazone increased adipose GPx3 expression in obese and diabetic db/db mice. Moreover, GPx3 overexpression in adipocytes improved high glucose-induced insulin resistance and attenuated inflammatory gene expression whereas GPx3 neutralization in adipocytes promoted expression of proinflammatory genes. Taken together, these data suggest that suppression of GPx3 expression in the adipose tissue of obese subjects might constitute a vicious cycle to expand local reactive oxygen species accumulation in adipose tissue potentially into systemic oxidative stress and obesity-related metabolic complications.


Author(s):  
Jamaira Aparecida Victorio ◽  
Ana Paula Davel

Most of the systemic blood vessels are surrounded by the perivascular adipose tissue (PVAT). Healthy PVAT is anticontractile and anti-inflammatory, but a dysfunctional PVAT has been suggested to link cardiometabolic risk factors to vascular dysfunction. Vascular oxidative stress is an important pathophysiological event in cardiometabolic complications of obesity, type 2 diabetes, and hypertension. PVAT-derived adipocytes generate reactive oxygen species (ROS) including superoxide anion and hydrogen peroxide that might signal to vascular wall. Therefore, an abnormal generation of ROS by PVAT emerges as a potential pathophysiological mechanism underlying vascular injury. This review summarizes new findings describing ROS production in PVAT of several vascular beds, major sources of ROS in this tissue including mitochondria, NADPH oxidase and eNOS uncoupled, and finally, changes in ROS production affecting vascular function in the presence of cardiometabolic risk factors and diseases.


Author(s):  
E. Martínez-Martínez ◽  
R. Jurado-López ◽  
P. Cervantes-Escalera ◽  
V. Cachofeiro ◽  
M. Miana

AbstractObesity and excess of adipose tissue are associated with the development of cardiovascular risk factors such as diabetes, hypertension, and hyperlipidemia. At the cardiac level, various morphological adaptations in cardiac structure and function occur in obese individuals. Different mechanisms linking obesity to these modifications have been postulated. Adipose tissue and epicardial fat releases a large number of cytokines and bioactive mediators such as leptin. Leptin circulates in proportion to body fat mass, thus serving as a satiety signal and informing central metabolic control centers as to the status of peripheral energy stores. It participates in numerous other functions both peripherally and centrally, as indicated by the wide distribution of leptin and the different isoforms of its receptor in different tissues including the heart. This hormone has distinct effects on the reproductive, cardiovascular, and immune systems; however, its role in the heart could mediate wide physiological effects observed in obese individuals. Oxidative stress is associated with obesity and may be considered to be a unifying mechanism in the development of obesity-related comorbidities. It has been reported that obesity may induce systemic oxidative stress; in turn, oxidative stress is associated with an irregular production of adipokines. We herein review the current knowledge of cardiac effects of leptin and the possible mechanisms that are involved, including oxidative stress that plays a major role in the development of cardiovascular damage.


2018 ◽  
Vol 96 (10) ◽  
pp. 1012-1016 ◽  
Author(s):  
Andreea I. Privistirescu ◽  
Alexandra Sima ◽  
Oana M. Duicu ◽  
Romulus Timar ◽  
Mariana G. Roșca ◽  
...  

Endothelial dysfunction and the related increase in reactive oxygen species (ROS) production are important events in the pathophysiology of diabetes mellitus (DM). Methylene blue (MB) has been systematically investigated for its protective effects against refractory hypotension and mitochondrial dysfunction. We have previously demonstrated that MB improved mitochondrial respiration and partially decreased oxidative stress in diabetic rat hearts. The present study was aimed to investigate whether MB modulates vascular function and ROS production in thoracic aortic rings isolated from rats with streptozotocin-induced DM (after 4 weeks of hyperglycemia). The effects of MB (0.1 μM, 30 min ex vivo incubation) on vascular reactivity in organ chamber (phenylephrine-induced contraction, acetylcholine-induced relaxation) and H2O2production (assessed by ferrous iron xylenol orange oxidation assay) were investigated in vascular preparations with intact endothelium and after denudation. DM elicited a significant alteration of vascular function: increased contractility to phenylephrine, attenuation of acetylcholine-dependent relaxation, and augmented H2O2generation. Ex vivo incubation with MB partially reversed all these changes (by approximately 70%) in vascular segments with intact endothelial layer (but not in denuded vessels). In conclusion, MB might be useful in alleviating endothelial dysfunction and mitigating endothelial oxidative stress, observations that clearly require further investigation in the setting of cardiometabolic disease.


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