Hydroxytyrosol Ameliorates Endothelial Function under Inflammatory Conditions by Preventing Mitochondrial Dysfunction

Mitochondria are fundamental organelles producing energy and reactive oxygen species (ROS); their impaired functions play a key role in endothelial dysfunction. Hydroxytyrosol (HT), a well-known olive oil antioxidant, exerts health benefits against vascular diseases by improving endothelial function. However, the HT role in mitochondrial oxidative stress in endothelial dysfunction is not clear yet. To investigate the HT effects on mitochondrial ROS production in the inflamed endothelium, we used an in vitro model of endothelial dysfunction represented by cultured endothelial cells, challenged with phorbol myristate acetate (PMA), an inflammatory, prooxidant, and proangiogenic agent. We found that the pretreatment of endothelial cells with HT (1–30 μmol/L) suppressed inflammatory angiogenesis, a crucial aspect of endothelial dysfunction. The HT inhibitory effect is related to reduced mitochondrial superoxide production and lipid peroxidation and to increased superoxide dismutase activity. HT, in a concentration-dependent manner, improved endothelial mitochondrial function by reverting the PMA-induced reduction of mitochondrial membrane potential, ATP synthesis, and ATP5β expression. In PMA-challenged endothelial cells, HT also promoted mitochondrial biogenesis through increased mitochondrial DNA content and expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha, nuclear respiratory factor-1, and mitochondrial transcription factor A. These results highlight that HT blunts endothelial dysfunction and pathological angiogenesis by ameliorating mitochondrial function, thus suggesting HT as a potential mitochondria-targeting antioxidant in the inflamed endothelium.

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PPAR-αAgonist Fenofibrate Upregulates Tetrahydrobiopterin Level through Increasing the Expression of Guanosine 5′-Triphosphate Cyclohydrolase-I in Human Umbilical Vein Endothelial Cells

PPAR Research ◽

10.1155/2011/523520 ◽

2011 ◽

Vol 2011 ◽

pp. 1-8 ◽

Cited By ~ 12

Author(s):

Jinbo Liu ◽

Changlin Lu ◽

Fuwang Li ◽

Haining Wang ◽

Liyun He ◽

...

Keyword(s):

Endothelial Cells ◽

Umbilical Vein ◽

Control Group ◽

Peroxisome Proliferator ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Peroxisome Proliferator Activated Receptor ◽

Human Umbilical Vein ◽

Umbilical Vein Endothelial Cells

Tetrahydrobiopterin (BH4) is an essential cofactor for endothelial nitric oxide (NO) synthase. Guanosine 5′-triphosphate cyclohydrolase-I (GTPCH-I) is a key limiting enzyme for BH4 synthesis. In the present in vitro study, we investigated whether peroxisome proliferator-activated receptorα(PPAR-α) agonist fenofibrate could recouple eNOS by reversing low-expression of intracellular BH4 in endothelial cells and discussed the potential mechanisms. After human umbilical vein endothelial cells (HUVECs) were treated with lipopolysaccharide (LPS) for 24 hours, the levels of cellular eNOS, BH4 and cell supernatant NO were significantly reduced compared to control group. And the fluorescence intensity of intracellular ROS was significantly increased. But pretreated with fenofibrate (10 umol/L) for 2 hours before cells were induced by LPS, the levels of eNOS, NO, and BH4 were significantly raised compared to LPS treatment alone. ROS production was markedly reduced in fenofibrate group than LPS group. In addition, our results showed that the level of intracellular GTPCH-I detected by western blot was increased in a concentration-dependent manner after being treated with fenofibrate. These results suggested that fenofibrate might help protect endothelial function and against atherosclerosis by increasing level of BH4 and decreasing production of ROS through upregulating the level of intracellular GTPCH-I.

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The Peroxisome Proliferator-Activated Receptor γ Agonist Pioglitazone Protects Vascular Endothelial Function in Hypercholesterolemic Rats by Inhibiting Myeloperoxidase

Cardiology Research and Practice ◽

10.1155/2020/1845969 ◽

2020 ◽

Vol 2020 ◽

pp. 1-9

Author(s):

Dapeng Zhang ◽

Yehong Wang ◽

Ming Yi ◽

Suli Zhang ◽

Ye Wu

Keyword(s):

Endothelial Dysfunction ◽

Endothelial Function ◽

Negative Correlation ◽

Intervention Group ◽

Cgmp Level ◽

Peroxisome Proliferator ◽

Vascular Endothelial ◽

Vascular Endothelial Function ◽

Peroxisome Proliferator Activated Receptor

Objective. Hypercholesterolemia- (HC-) induced endothelial dysfunction is the first step of atherogenesis, and the peroxisome proliferator-activated receptor γ (PPARγ) has been reported to attenuate atherosclerosis formation; however, the underlying mechanisms are not fully understood. The present study was designed to determine whether myeloperoxidase (MPO) mediates HC-induced endothelial dysfunction and the role of the PPARγ agonist pioglitazone (PIO) in attenuating endothelial dysfunction. Methods. Male Wistar rats were fed with normal or high cholesterol diets for 8 weeks. HC rats were randomized to receive dapsone (DDS, the MPO inhibitor) during the last 6 days or PIO for the remaining 4 weeks. Vascular endothelial function was determined by comparing vasorelaxation to ACh, an endothelium-dependent vasodilator, and SNP, an endothelium-independent vasodilator in vascular rings in vitro. The vascular MPO activity, NOx content, and cGMP level were measured by the MPO activity assay kit, NO assay kit, and cGMP RIA kit. Results. Compared with rats fed with normal diet, endothelium-dependent vasodilation, NOx content, and cGMP level were decreased, and MPO activity was increased in thoracic aortas of rats fed with HC diet. There was a negative correlation between vascular endothelial function, NOx content or cGMP level, and MPO activity. PIO obviously reduced the MPO activity, increased NOx content and cGMP level, and improved endothelium-dependent vasodilation function in HC rats, which was essentially the same as that seen with DDS. And, there was a negative correlation between vascular endothelial function, NOx content or cGMP level, and MPO activity in the HC group and the PIO intervention group. Conclusion. MPO might provoke vascular endothelial dysfunction in hypercholesterolemic rats by reducing the NO biological activity and impairing the NO/cGMP/cGK signaling pathway. PIO might inhibit vascular MPO activity and increase NO bioavailability with the net result of reversing endothelial dysfunction.

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Endothelial Dysfunction in Fabry Disease Is Related to Glycocalyx Degradation

Frontiers in Immunology ◽

10.3389/fimmu.2021.789142 ◽

2021 ◽

Vol 12 ◽

Author(s):

Solvey Pollmann ◽

David Scharnetzki ◽

Dominique Manikowski ◽

Malte Lenders ◽

Eva Brand

Keyword(s):

Endothelial Cells ◽

Endothelial Dysfunction ◽

Endothelial Function ◽

Fabry Disease ◽

Specific Inhibitor ◽

Small Vessel ◽

Endothelial Glycocalyx ◽

Enzyme Replacement ◽

Anti Inflammatory

Fabry disease (FD) is an X-linked multisystemic lysosomal storage disease due to a deficiency of α-galactosidase A (GLA/AGAL). Progressive cellular accumulation of the AGAL substrate globotriaosylceramide (Gb3) leads to endothelial dysfunction. Here, we analyzed endothelial function in vivo and in vitro in an AGAL-deficient genetic background to identify the processes underlying this small vessel disease. Arterial stiffness and endothelial function was prospectively measured in five males carrying GLA variants (control) and 22 FD patients under therapy. AGAL-deficient endothelial cells (EA.hy926) and monocytes (THP1) were used to analyze endothelial glycocalyx structure, function, and underlying inflammatory signals. Glycocalyx thickness and small vessel function improved significantly over time (p<0.05) in patients treated with enzyme replacement therapy (ERT, n=16) and chaperones (n=6). AGAL-deficient endothelial cells showed reduced glycocalyx and increased monocyte adhesion (p<0.05). In addition, increased expression of angiopoietin-2, heparanase and NF-κB was detected (all p<0.05). Incubation of wild-type endothelial cells with pathological globotriaosylsphingosine concentrations resulted in comparable findings. Treatment of AGAL-deficient cells with recombinant AGAL (p<0.01), heparin (p<0.01), anti-inflammatory (p<0.001) and antioxidant drugs (p<0.05), and a specific inhibitor (razuprotafib) of angiopoietin-1 receptor (Tie2) (p<0.05) improved glycocalyx structure and endothelial function in vitro. We conclude that chronic inflammation, including the release of heparanases, appears to be responsible for the degradation of the endothelial glycocalyx and may explain the endothelial dysfunction in FD. This process is partially reversible by FD-specific and anti-inflammatory treatment, such as targeted protective Tie2 treatment.

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Methanol Extract of Mongolian Iris bungei Maxim. Stimulates 3T3-L1 Adipocyte Differentiation

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2021.19160 ◽

2021 ◽

Vol 21 (7) ◽

pp. 3943-3949

Author(s):

Jaegoo Yeon ◽

Sung-Suk Suh ◽

Ui-Joung Youn ◽

Badamtsetseg Bazarragchaa ◽

Ganbold Enebish ◽

...

Keyword(s):

Bacterial Infections ◽

Fatty Acid Synthase ◽

Molecular Mechanisms ◽

Adipocyte Differentiation ◽

Methanol Extract ◽

Regulatory Element ◽

Peroxisome Proliferator ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Peroxisome Proliferator Activated Receptor

Iris bungei Maxim. (IB), which is native to China and Mongolia, is used as a traditional medicine for conditions such as inflammation, cancer, and bacterial infections. However, the effects of Iris bungei Maxim. on adipocyte differentiation have not been studied. In the present study, we first demonstrated the molecular mechanisms underlying the adipogenic activity of the methanol extract of Mongolian I. bungei Maxim. (IB). IB significantly enhanced intracellular lipid accumulation and adipocyte differentiation in 3T3-L1 preadipocytes in a concentration-dependent manner. Moreover, IB markedly stimulated the expression of genes related to adipogenesis such as peroxisome proliferator-activated receptor γ, adiponectin, and aP2. In addition, we also observed that IB induces lipogenic genes such as fatty acid synthase, sterol regulatory element binding protein 1c, stearoyl-CoA desaturase, and acetyl-CoA carboxylase. Interestingly IB regulated adipocyte differentiation in both the early and middle stages. Taken together, these adipogenic and lipogenic effects of IB suggest its efficacy for the prevention and/or treatment of type 2 diabetes.

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Peroxisome Proliferator-Activated Receptor-γ Antagonizes LOX-1-Mediated Endothelial Injury by Transcriptional Activation of miR-590-5p

PPAR Research ◽

10.1155/2019/2715176 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9

Author(s):

Lei Xu ◽

Gang Zhao ◽

Hong Zhu ◽

Shijun Wang ◽

Aijun Sun ◽

...

Keyword(s):

Endothelial Cells ◽

Transcriptional Activation ◽

Promoter Region ◽

Nuclear Translocation ◽

Therapeutic Potential ◽

Umbilical Vein ◽

Density Lipoprotein ◽

Peroxisome Proliferator ◽

Peroxisome Proliferator Activated Receptor

Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is one of the major receptors expressed on the endothelium of arterial wall with a key role in endothelial dysfunction and the development of atherosclerosis. Recent evidence suggested that LOX-1 is upregulated under the condition of insulin resistance and could be suppressed by the antidiabetic drugs. We previously also confirmed that Thiazolidinedione (TZD) has the inhibitory effect on LOX-1 in ox-LDL-induced endothelial cells. However, the underlying mechanism is unclear. Here we showed that Rosiglitazone treatment significantly attenuated the expressions of LOX-1, ICAM-1, VCAM-1, p47phox, and the atherosclerotic lesions in ApoE-/- mice with high-fat diet. In vitro, we revealed that Rosiglitazone inhibited LOX-1 by regulating miR-590-5p. Ox-LDL-mediated ICAM-1, VCAM-1, and p47phox were significantly reduced by Rosiglitazone, but all reversed after pretreating the cells with antagomiR-590-5p. Induction with Rosiglitazone activated PPAR-γ and promoted its nuclear translocation in cultured human umbilical vein endothelial cells (HUVECs). The nuclear PPAR-γ upregulated the miR-590-5p level through binding to its transcriptional promoter region. Retaining PPAR-γ in cytoplasm by transfecting with PPAR-γ⊿NLS plasmid in HUVECs failed to activate miR-590-5p. Mutation of the promoter region of PPAR-γ also reduced the miR-590-5p promoter luciferase activity. Collectively, these data indicated that PPAR-γ may have the therapeutic potential in atherosclerosis via the transcriptional regulation of miR-590-5p in endothelial cells.

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Differential regulation of metabolism by nitric oxide andS-nitrosothiols in endothelial cells

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00210.2011 ◽

2011 ◽

Vol 301 (3) ◽

pp. H803-H812 ◽

Cited By ~ 21

Author(s):

Anne R. Diers ◽

Katarzyna A. Broniowska ◽

Victor M. Darley-Usmar ◽

Neil Hogg

Keyword(s):

Nitric Oxide ◽

Endothelial Cells ◽

Oxidative Phosphorylation ◽

Metabolic Pathways ◽

Nitrosative Stress ◽

Surrogate Marker ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

No Donor

S-nitrosation of thiols in key proteins in cell signaling pathways is thought to be an important contributor to nitric oxide (NO)-dependent control of vascular (patho)physiology. Multiple metabolic enzymes are targets of both NO and S-nitrosation, including those involved in glycolysis and oxidative phosphorylation. Thus it is important to understand how these metabolic pathways are integrated by NO-dependent mechanisms. Here, we compared the effects of NO and S-nitrosation on both glycolysis and oxidative phosphorylation in bovine aortic endothelial cells using extracellular flux technology to determine common and unique points of regulation. The compound S-nitroso-l-cysteine (l-CysNO) was used to initiate intracellular S-nitrosation since it is transported into cells and results in stable S-nitrosation in vitro. Its effects were compared with the NO donor DetaNONOate (DetaNO). DetaNO treatment caused only a decrease in the reserve respiratory capacity; however, l-CysNO impaired both this parameter and basal respiration in a concentration-dependent manner. In addition, DetaNO stimulated extracellular acidification rate (ECAR), a surrogate marker of glycolysis, whereas l-CysNO stimulated ECAR at low concentrations and inhibited it at higher concentrations. Moreover, a temporal relationship between NO- and S-nitrosation-mediated effects on metabolism was identified, whereby NO caused a rapid impairment in mitochondrial function, which was eventually overwhelmed by S-nitrosation-dependent processes. Taken together, these results suggest that severe pharmacological nitrosative stress may differentially regulate metabolic pathways through both intracellular S-nitrosation and NO-dependent mechanisms. Moreover, these data provide insight into the role of NO and related compounds in vascular (patho)physiology.

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The mechanism of low molecular weight heparin (LMWH) inhibition of tumor growth

Journal of Clinical Oncology ◽

10.1200/jco.2006.24.18_suppl.13093 ◽

2006 ◽

Vol 24 (18_suppl) ◽

pp. 13093-13093 ◽

Cited By ~ 4

Author(s):

S. L. Smiley ◽

D. O. Henry ◽

M. K. Wong

Keyword(s):

Endothelial Cells ◽

Tumor Growth ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Receptor System ◽

Fgf Receptor ◽

Tumor Inhibition ◽

Inhibition Of Tumor Growth

13093 Background: Clinical studies show that LMWHs improve survival in cancer patients. There is compelling and mounting evidence that non-anticoagulation factors are at play, and that these may be contributing in a major way to improved patient outcome. Methods and Results: Dalteparin, enoxaparin, and tinzaparin were tested for their in vivo ability to inhibit tumor lines engineered for aggressive angiogenesis-driven growth. Therapeutic daily doses of drug administered the day following tumor inoculation resulted in significant angiogenesis and tumor inhibition. We previously showed that LMWHs inhibit fibroblast growth factor (FGF) -induced mitogenesis of Tumor Derived Endothelial Cells (TDECs) in a time and concentration dependent manner in vitro. We now show that this endothelial inhibition occurs through LMWHs-mediated reduction of phosphorylation and down stream signaling through ERK. The potency of LMWH was significantly reduced when TDECs were pretreated with heparinase- suggesting that the molecular target for LMWH may be the cell surface, low affinity FGF receptor system. Both our in vivo and in vitro studies demonstrate that angiogenesis and tumor inhibition are greatest for dalteparin > tinzaparin > enoxaparin. Clues to the heparin-TDECs interaction comes from tracking the real-time movement of FGF using a highly fluorescent nanocrystal bead decorated on its surface with FGF. High resolution video-microscopy shows FGF binding onto TDEC surfaces, but once heparin enters the environment, FGF detaches from the TDECs and migrates to the heparin. This ultimately results in significant TDEC growth inhibition as compared to controls. Conclusion: LMWH treatment at pharmacologic doses significantly blunts tumor growth and angiogenesis. This inhibition resides in part via heparin’s ability to sequester FGF from the low affinity receptor system on tumor endothelial cells. No significant financial relationships to disclose.

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PRIC295, a Nuclear Receptor Coactivator, Identified from PPAR-Interacting Cofactor Complex

PPAR Research ◽

10.1155/2010/173907 ◽

2010 ◽

Vol 2010 ◽

pp. 1-16 ◽

Cited By ~ 9

Author(s):

Sean R. Pyper ◽

Navin Viswakarma ◽

Yuzhi Jia ◽

Yi-Jun Zhu ◽

Joseph D. Fondell ◽

...

Keyword(s):

Nuclear Receptor ◽

Target Genes ◽

Peroxisome Proliferator ◽

Dependent Manner ◽

Peroxisome Proliferator Activated Receptor ◽

Nuclear Receptor Coactivator ◽

Evolutionarily Conserved

The peroxisome proliferator-activated receptor- (PPAR) plays a key role in lipid metabolism and energy combustion. Chronic activation of PPAR in rodents leads to the development of hepatocellular carcinomas. The ability of PPAR to induce expression of its target genes depends on Mediator, an evolutionarily conserved complex of cofactors and, in particular, the subunit 1 (Med1) of this complex. Here, we report the identification and characterization of PPAR-interacting cofactor (PRIC)-295 (PRIC295), a novel coactivator protein, and show that it interacts with the Med1 and Med24 subunits of the Mediator complex. PRIC295 contains 10 LXXLL signature motifs that facilitate nuclear receptor binding and interacts with PPAR and five other members of the nuclear receptor superfamily in a ligand-dependent manner. PRIC295 enhances the transactivation function of PPAR, PPAR, and ER. These data demonstrate that PRIC295 interacts with nuclear receptors such as PPAR and functions as a transcription coactivator underin vitroconditions and may play an important role in mediating the effectsin vivoas a member of the PRIC complex with Med1 and Med24.

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PPARs and angiogenesis

Biochemical Society Transactions ◽

10.1042/bst20110643 ◽

2011 ◽

Vol 39 (6) ◽

pp. 1601-1605 ◽

Cited By ~ 51

Author(s):

David Bishop-Bailey

Keyword(s):

Endothelial Cells ◽

Critical Role ◽

Molecular Target ◽

Experimental Models ◽

Peroxisome Proliferator ◽

Peroxisome Proliferator Activated Receptor ◽

Angiogenic Switch ◽

Receptor Family

The PPAR (peroxisome-proliferator-activated receptor) family consists of three ligand-activated nuclear receptors: PPARα, PPARβ/δ and PPARγ. These PPARs have important roles in the regulation of glucose and fatty acid metabolism, cell differentiation and immune function, but were also found to be expressed in endothelial cells in the late 1990s. The early endothelial focus of PPARs was PPARγ, the molecular target for the insulin-sensitizing thiazolidinedione/glitazone class of drugs. Activation of PPARγ was shown to inhibit angiogenesis in vitro and in models of retinopathy and cancer, whereas more recent data point to a critical role in the development of the vasculature in the placenta. Similarly, PPARα, the molecular target for the fibrate class of drugs, also has anti-angiogenic properties in experimental models. In contrast, unlike PPARα or PPARγ, activation of PPARβ/δ induces angiogenesis, in vitro and in vivo, and has been suggested to be a critical component of the angiogenic switch in pancreatic cancer. Moreover, PPARβ/δ is an exercise mimetic and appears to contribute to the angiogenic remodelling of cardiac and skeletal muscle induced by exercise. This evidence and the emerging mechanisms by which PPARs act in endothelial cells are discussed in more detail.

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The endocrine disruptor mono-(2-ethylhexyl)phthalate promotes adipocyte differentiation and induces obesity in mice

Bioscience Reports ◽

10.1042/bsr20120042 ◽

2012 ◽

Vol 32 (6) ◽

pp. 619-629 ◽

Cited By ~ 106

Author(s):

Chanjuan Hao ◽

Xuejia Cheng ◽

Hongfei Xia ◽

Xu Ma

Keyword(s):

Target Genes ◽

Adipocyte Differentiation ◽

Cell Model ◽

Peroxisome Proliferator ◽

Dependent Manner ◽

Peroxisome Proliferator Activated Receptor ◽

Glucose Levels ◽

Ethylhexyl Phthalate

The environmental obesogen hypothesis proposes that exposure to endocrine disruptors during developmental ‘window’ contributes to adipogenesis and the development of obesity. MEHP [mono-(2-ethylhexyl) phthalate], a metabolite of the widespread plasticizer DEHP [di-(2-ethylhexyl) phthalate], has been found in exposed organisms and identified as a selective PPARγ (peroxisome-proliferator-activated receptor γ) modulator. However, implication of MEHP on adipose tissue development has been poorly investigated. In the present study, we show the dose-dependent effects of MEHP on adipocyte differentiation and GPDH (glycerol-3-phosphate dehydrogenase) activity in the murine 3T3-L1 cell model. MEHP induced the expression of PPARγ as well as its target genes required for adipogenesis in vitro. Moreover, MEHP perturbed key regulators of adipogenesis and lipogenic pathway in vivo. In utero exposure to a low dose of MEHP significantly increased b.w. (body weight) and fat pad weight in male offspring at PND (postnatal day) 60. In addition, serum cholesterol, TAG (triacylglycerol) and glucose levels were also significantly elevated. These results suggest that perinatal exposure to MEHP may be expected to increase the incidence of obesity in a sex-dependent manner and can act as a potential chemical stressor for obesity and obesity-related disorders.

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