Regional variation in arterial stiffening and dysfunction in Western diet-induced obesity

Increased central vascular stiffening, assessed in vivo by determination of pulse wave velocity (PWV), is an independent predictor of cardiovascular event risk. Recent evidence demonstrates that accelerated aortic stiffening occurs in obesity; however, little is known regarding stiffening of other disease-relevant arteries or whether regional variation in arterial stiffening occurs in this setting. We addressed this gap in knowledge by assessing femoral PWV in vivo in conjunction with ex vivo analyses of femoral and coronary structure and function in a mouse model of Western diet (WD; high-fat/high-sugar)-induced obesity and insulin resistance. WD feeding resulted in increased femoral PWV in vivo. Ex vivo analysis of femoral arteries revealed a leftward shift in the strain-stress relationship, increased modulus of elasticity, and decreased compliance indicative of increased stiffness following WD feeding. Confocal and multiphoton fluorescence microscopy revealed increased femoral stiffness involving decreased elastin/collagen ratio in conjunction with increased femoral transforming growth factor-β (TGF-β) content in WD-fed mice. Further analysis of the femoral internal elastic lamina (IEL) revealed a significant reduction in the number and size of fenestrae with WD feeding. Coronary artery stiffness and structure was unchanged by WD feeding. Functionally, femoral, but not coronary, arteries exhibited endothelial dysfunction, whereas coronary arteries exhibited increased vasoconstrictor responsiveness not present in femoral arteries. Taken together, our data highlight important regional variations in the development of arterial stiffness and dysfunction associated with WD feeding. Furthermore, our results suggest TGF-β signaling and IEL fenestrae remodeling as potential contributors to femoral artery stiffening in obesity.

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Tracking a TGF-β activator in vivo: sensitive PET imaging of αvβ8-integrin with the Ga-68-labeled cyclic RGD octapeptide trimer Ga-68-Triveoctin

EJNMMI Research ◽

10.1186/s13550-020-00706-1 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Neil Gerard Quigley ◽

Katja Steiger ◽

Frauke Richter ◽

Wilko Weichert ◽

Sebastian Hoberück ◽

...

Keyword(s):

Human Subject ◽

Transforming Growth Factor ◽

Epithelial Mesenchymal Transition ◽

Ex Vivo ◽

Transforming Growth Factor Β ◽

Integrin Expression ◽

Target Tissue ◽

Mesenchymal Transition ◽

Positron Emission

Abstract Purpose As a major activator of transforming growth factor β (TGF-β), the RGD receptor αvβ8-integrin is involved in pathogenic processes related to TGF-β dysregulation, such as tumor growth, invasion, and radiochemoresistance, metastasis and tumor cell stemness, as well as epithelial-mesenchymal transition. The novel positron emission tomography (PET) radiopharmaceutical Ga-68-Triveoctin for in vivo mapping of αvβ8-integrin expression might enhance the prognosis of certain tumor entities, as well as support and augment TGF-β-targeted therapeutic approaches. Methods Monomeric and trimeric conjugates of cyclo(GLRGDLp(NMe)K(pent-4-ynoic amide)) were synthesized by click chemistry (CuAAC), labeled with Ga-68, and evaluated in MeWo (human melanoma) xenografted SCID mice by means of PET and ex-vivo biodistribution. αvβ8-integrin expression in murine tissues was determined by β8-IHC. A human subject received a single injection of 173 MBq of Ga-68-Triveoctin and underwent 3 subsequent PET/CT scans at 25, 45, and 90 min p.i.. Results The trimer Ga-68-Triveoctin exhibits a 6.7-fold higher αvβ8-integrin affinity than the monomer (IC50 of 5.7 vs. 38 nM, respectively). Accordingly, biodistribution showed a higher tumor uptake (1.9 vs. 1.0%IA/g, respectively) but a similar baseline upon blockade (0.25%IA/g for both). IHC showed an intermediate β8-expression in the tumor while most organs and tissues were found β8-negative. Low non-target tissue uptakes (< 0.4%IA/g) confirmed a low degree of unspecific binding. Due to its hydrophilicity (log D = − 3.1), Ga-68-Triveoctin is excreted renally and shows favorable tumor/tissue ratios in mice (t/blood: 6.7; t/liver: 6.8; t/muscle: 29). A high kidney uptake in mice (kidney-to-blood and -to-muscle ratios of 126 and 505, respectively) is not reflected by human PET (corresponding values are 15 and 30, respectively), which furthermore showed notable uptakes in coeliac and choroid plexus (SUVmean 6.1 and 9.7, respectively, 90 min p.i.). Conclusion Ga-68-Triveoctin enables sensitive in-vivo imaging αvβ8-integrin expression in murine tumor xenografts. PET in a human subject confirmed a favorable biodistribution, underscoring the potential of Ga-68-Triveoctin for mapping of αvβ8-integrin expression in a clinical setting.

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Arterial Stiffening in Western Diet-Fed Mice Is Associated with Increased Vascular Elastin, Transforming Growth Factor-β, and Plasma Neuraminidase

Frontiers in Physiology ◽

10.3389/fphys.2016.00285 ◽

2016 ◽

Vol 7 ◽

Cited By ~ 17

Author(s):

Christopher A. Foote ◽

Jorge A. Castorena-Gonzalez ◽

Francisco I. Ramirez-Perez ◽

Guanghong Jia ◽

Michael A. Hill ◽

...

Keyword(s):

Growth Factor ◽

Transforming Growth Factor ◽

Transforming Growth Factor Β ◽

Western Diet ◽

Arterial Stiffening ◽

Vascular Elastin

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OR17-06 Transglutaminase 2 Inhibition Reduces Aortic Stiffness in Western Diet-Fed Female Mice

Journal of the Endocrine Society ◽

10.1210/jendso/bvaa046.416 ◽

2020 ◽

Vol 4 (Supplement_1) ◽

Author(s):

Bhavana Chinnakotla ◽

Camila Margarita Manrique Acevedo ◽

Padilla Jaume ◽

Makenzie L Woodford ◽

Annayya R Aroor ◽

...

Keyword(s):

Aortic Stiffness ◽

Weight Control ◽

Ex Vivo ◽

Transglutaminase 2 ◽

Competitive Inhibitor ◽

Tolerance Test ◽

Western Diet ◽

Arterial Stiffening ◽

Female Mice

Abstract Widespread consumption of diets high in fat, sugars and salt (Western diet, WD) is associated arterial stiffening, which is a major independent risk factor for cardiovascular disease (CVD). Notably, while WD feeding increases the risk of CVD in both males and females, the latter are more prone to develop arterial stiffening. However, the mechanisms underlying WD-induced arterial stiffening are poorly understood, particularly in females, and there are currently no specific treatments targeted at vascular stiffening.Tissue transglutaminase 2 (TG2) is an enzyme that mediates the cross-linking and stabilization of extracellular matrix proteins such as collagen, and promotes the polymerization of actin stress fibers of the cytoskeleton. It is ubiquitously expressed and abundantly present in the vasculature. Mounting evidence implicates TG2 activation in the pathogenesis of arterial stiffening and vascular fibrosis. Herein we propose that TG2 activation is central to WD-induced arterial stiffening and sought to determine the efficacy of cystamine (a non-specific competitive inhibitor of TG2) for reducing arterial stiffening in the setting of WD consumption. Accordingly, we fed 20 female mice (4 weeks old) a WD (4.65 kcal/g of food, fat 46% kcals, high-fructose corn syrup 17.5%, sucrose 17.5%, protein 17.6%, salt 1.6%) for 43 weeks. Ten of these mice received cystamine (40 mg/Kg/d in the drinking water) during their last 8 weeks on the WD. Another group of female mice (n=10) fed regular chow was used as reference controls. Aortic stiffness was measured in vivo via ultrasound-based pulse wave velocity and ex vivo by aortic explant atomic force microscopy. Vasomotor responses were assessed in isolated aortic rings via wire myography.Cystamine did not influence glucose homeostasis (intraperitoneal glucose tolerance test) or blood pressure (tail-cuff) (control 77.208±2.229 mm Hg versus WD 77.208±6.077 versus WD+Cystamine 76.297±7.894), but it was associated with increased body weight (control 26.860±2.215 grams versus WD 25.320±2.889 versus WD+Cystamine 33.220±4.848, p<0.05). Notably, cystamine reduced aortic stiffness in WD-fed mice both in vivo and ex vivo such that differences between chow-fed and WD-fed mice were normalized (control 5.294±1.713 versus WD 11.735±5.962 p≤0.05, control 5.294±1.713 versus WD+Cystamine 3.940±0.378 KPa, p<0.05). In addition, WD-induced impairments in endothelium-independent vasorelaxation (i.e. responses to sodium nitroprusside) were restored with cystamine. Collectively, our data show that cystamine reduces aortic stiffness and improves endothelium-independent vasorelaxation in female mice chronically exposed to WD, and that these effects occur despite an increase in weight gain. These findings implicate TG2 as a promising therapeutic target for reducing arterial stiffening in the context of chronic over-nutrition in females.

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Granulosal and thecal expression of bone morphogenetic protein- and activin-binding protein mRNA transcripts during bovine follicle development and factors modulating their expression in vitro

Reproduction ◽

10.1530/rep-11-0150 ◽

2011 ◽

Vol 142 (4) ◽

pp. 581-591 ◽

Cited By ~ 18

Author(s):

Claire Glister ◽

Leanne Satchell ◽

Phil G Knight

Keyword(s):

Bone Morphogenetic Proteins ◽

Transforming Growth Factor ◽

Ex Vivo ◽

Mrna Level ◽

Transcript Abundance ◽

Transforming Growth Factor Β ◽

Follicle Development ◽

Mrna Levels ◽

Theca Interna

Evidence supports local roles for transforming growth factor β superfamily members including activins and bone morphogenetic proteins (BMP) in follicle development. Access of these ligands to signalling receptors is likely modulated by extracellular binding proteins (BP). In this study, we comparedex vivoexpression of four BPs (chordin, gremlin, noggin and follistatin) in granulosal (GC) and theca interna (TC) compartments of developing bovine antral follicles (1–18 mm). Effects of FSH and IGF on BMP and BP expression by cultured GC, and effects of LH and BMPs on BP expression by cultured TC were also examined. Follicular expression of all four BP transcripts was higher in GC than TC compartments (P<0.001) a finding confirmed by immunohistochemistry. Follicle category affected (P<0.01) gremlin and follistatin mRNA abundance, with a significant cell-type×follicle category interaction for chordin, follistatin and noggin. Noggin transcript abundance was lower (P<0.05) in GC of large ‘E-active’ than ‘E-inactive’ follicles while follistatin mRNA level was higher (P<0.01). FSH enhanced CYP19, FSHR, INHBA and follistatin by GC without affecting BMP or BMP–BP expression. IGF increased CYP19 and follistatin, reduced BMP4, noggin and gremlin but did not affect chordin orFSHRmRNA levels. LH increased TC androgen secretion but had no effect on BMP or BP expression. BMPs uniformly suppressed TC androgen production whilst increasing chordin, noggin and gremlin mRNA levels up to 20-fold (P<0.01). These findings support the hypothesis that extracellular BP, mostly from GC, contribute to the regulation of intrafollicular BMP/activin signalling. Enhancement of thecal BP expression by BMP implies an autoregulatory feedback role to prevent excessive signalling.

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Intravenous Injection of Clinical Grade Human MSCs after Experimental Stroke: Functional Benefit and Microvascular Effect

Cell Transplantation ◽

10.3727/096368916x691132 ◽

2016 ◽

Vol 25 (12) ◽

pp. 2157-2171 ◽

Cited By ~ 12

Author(s):

Anaïck Moisan ◽

Isabelle Favre ◽

Claire Rome ◽

Florence De Fraipont ◽

Emmanuelle Grillon ◽

...

Keyword(s):

Transforming Growth Factor ◽

Ex Vivo ◽

Quantitative Polymerase Chain Reaction ◽

Transforming Growth Factor Β1 ◽

Angiogenic Factors ◽

Experimental Stroke ◽

Vascular Density ◽

Human Mscs ◽

Functional Benefit

Stroke is the leading cause of disability in adults. Many current clinical trials use intravenous (IV) administration of human bone marrow-derived mesenchymal stem cells (BM-MSCs). This autologous graft requires a delay for ex vivo expansion of cells. We followed microvascular effects and mechanisms of action involved after an IV injection of human BM-MSCs (hBM-MSCs) at a subacute phase of stroke. Rats underwent a transient middle cerebral artery occlusion (MCAo) or a surgery without occlusion (sham) at day 0 (D0). At D8, rats received an IV injection of 3 million hBM-MSCs or PBS-glutamine. In a longitudinal behavioral follow-up, we showed delayed somatosensory and cognitive benefits 4 to 7 weeks after hBM-MSC injection. In a separate longitudinal in vivo magnetic resonance imaging (MRI) study, we observed an enhanced vascular density in the ischemic area 2 and 3 weeks after hBM-MSC injection. Histology and quantitative polymerase chain reaction (qPCR) revealed an overexpression of angiogenic factors such as Ang1 and transforming growth factor-β1 (TGF-β1) at D16 in hBM-MSC-treated MCAo rats compared to PBS-treated MCAo rats. Altogether, delayed IV injection of hBM-MSCs provides functional benefits and increases cerebral angiogenesis in the stroke lesion via a release of endogenous angiogenic factors enhancing the stabilization of newborn vessels. Enhanced angiogenesis could therefore be a means of improving functional recovery after stroke.

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The Anti-Cancer Effects of a Zotarolimus and 5-Fluorouracil Combination Treatment on A549 Cell-Derived Tumors in BALB/c Nude Mice

International Journal of Molecular Sciences ◽

10.3390/ijms22094562 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4562

Author(s):

Ching-Feng Wu ◽

Ching-Yang Wu ◽

Robin Y.-Y. Chiou ◽

Wei-Cheng Yang ◽

Chuen-Fu Lin ◽

...

Keyword(s):

Growth Factor ◽

Tumor Growth ◽

Lung Adenocarcinoma ◽

Nude Mice ◽

Transforming Growth Factor ◽

Human Lung ◽

Transforming Growth Factor Β ◽

Related Factors ◽

Human Lung Adenocarcinoma

Zotarolimus is a semi-synthetic derivative of rapamycin and a novel immunosuppressive agent used to prevent graft rejection. The pharmacological pathway of zotarolimus restricts the kinase activity of the mammalian target of rapamycin (mTOR), which potentially leads to reductions in cell division, cell growth, cell proliferation, and inflammation. These pathways have a critical influence on tumorigenesis. This study aims to examine the anti-tumor effect of zotarolimus or zotarolimus combined with 5-fluorouracil (5-FU) on A549 human lung adenocarcinoma cell line implanted in BALB/c nude mice by estimating tumor growth, apoptosis expression, inflammation, and metastasis. We established A549 xenografts in nude mice, following which we randomly divided the mice into four groups: control, 5-FU (100 mg/kg/week), zotarolimus (2 mg/kg/day), and zotarolimus combined with 5-FU. Compared the results with those for control mice, we found that mice treated with zotarolimus or zotarolimus combined with 5-FU retarded tumor growth; increased tumor apoptosis through the enhanced expression of cleaved caspase 3 and extracellular signal-regulated kinase (ERK) phosphorylation; decreased inflammation cytokines levels (e.g., IL-1β, TNF-α, and IL-6); reduced inflammation-related factors such as cyclooxygenase-2 (COX-2) protein and nuclear factor-κB (NF-κB) mRNA; enhanced anti-inflammation-related factors including IL-10 and inhibitor of NF-κB kinase α (IκBα) mRNA; and inhibited metastasis-related factors such as transforming growth factor β (TGF-β), CD44, epidermal growth factor receptor (EGFR), and vascular endothelial growth factor (VEGF). Notably, mice treated with zotarolimus combined with 5-FU had significantly retarded tumor growth, reduced tumor size, and increased tumor inhibition compared with the groups of mice treated with 5-FU or zotarolimus alone. The in vivo study confirmed that zotarolimus or zotarolimus combined with 5-FU could retard lung adenocarcinoma growth and inhibit tumorigenesis. Zotarolimus and 5-FU were found to have an obvious synergistic tumor-inhibiting effect on lung adenocarcinoma. Therefore, both zotarolimus alone and zotarolimus combined with 5-FU may be potential anti-tumor agents for treatment of human lung adenocarcinoma.

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Temporal transcriptomic profiling reveals dynamic changes in gene expression of Xenopus animal cap upon activin treatment

Scientific Reports ◽

10.1038/s41598-021-93524-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yumeko Satou-Kobayashi ◽

Jun-Dal Kim ◽

Akiyoshi Fukamizu ◽

Makoto Asashima

Keyword(s):

Time Course ◽

Transforming Growth Factor ◽

Transcriptome Profiling ◽

Transforming Growth Factor Β ◽

Activin A ◽

Cytokine Signaling ◽

Molecular Characteristics ◽

Transcriptional Dynamics

AbstractActivin, a member of the transforming growth factor-β (TGF-β) superfamily of proteins, induces various tissues from the amphibian presumptive ectoderm, called animal cap explants (ACs) in vitro. However, it remains unclear how and to what extent the resulting cells recapitulate in vivo development. To comprehensively understand whether the molecular dynamics during activin-induced ACs differentiation reflect the normal development, we performed time-course transcriptome profiling of Xenopus ACs treated with 50 ng/mL of activin A, which predominantly induced dorsal mesoderm. The number of differentially expressed genes (DEGs) in response to activin A increased over time, and totally 9857 upregulated and 6663 downregulated DEGs were detected. 1861 common upregulated DEGs among all Post_activin samples included several Spemann’s organizer genes. In addition, the temporal transcriptomes were clearly classified into four distinct groups in correspondence with specific features, reflecting stepwise differentiation into mesoderm derivatives, and a decline in the regulation of nuclear envelop and golgi. From the set of early responsive genes, we also identified the suppressor of cytokine signaling 3 (socs3) as a novel activin A-inducible gene. Our transcriptome data provide a framework to elucidate the transcriptional dynamics of activin-driven AC differentiation, reflecting the molecular characteristics of early normal embryogenesis.

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Targeting TAZ and YAP as a New Therapeutic Approach to Diabetic Nephropathy

Inquiry@Queen's Undergraduate Research Conference Proceedings ◽

10.24908/iqurcp.10044 ◽

2018 ◽

Author(s):

Lauren Chan

Keyword(s):

Transforming Growth Factor ◽

Primary Source ◽

Transforming Growth Factor Β ◽

Mechanical Stimuli ◽

Nuclear Retention ◽

Retention Factors ◽

Smad Signaling Pathway ◽

Nuclear Location ◽

Smad 3

Introduction Fibrosis is a major contributor to chronic kidney disease (CKD), for which no effective clinical treatment exists. The primary source of fibrosis is the activation of fibroblasts to the myofibroblast state. Fibroblast-myofibroblast transition requires transforming growth factor-β (TGF-β) and its canonical Smad signaling pathway. Purpose Recent findings suggest that mechanical stimuli affect fibroblast behavior. Nuclear localization of YAP/TAZ, closely associated mechanosensitive transcriptional co-factors, are regulated by substrate stiffness. As YAP/TAZ are Smad nuclear retention factors promoting TGF- β signaling, we hypothesized that YAP/TAZ inhibition could attenuate stiffness-mediated, TGF- β induced pro-fibrotic responses. Methods Immunostaining and immunoblotting were used to analyze localization and activity of YAP/TAZ and Smad levels, respectively. Results YAP/TAZ are in an active nuclear location in fibroblasts grown on stiff, fibrotic-like substrates (100kPa). In fibroblasts grown on soft substrates (2kPa), YAP/TAZ are primarily in an inactive cytosolic position. Cells grown on soft surfaces demonstrated strongly attenuated nuclear Smad 2/3 translocation and Smad-3 dependent transcription upon TGF-β stimulation, indicating impaired pro-fibrotic signaling. Verteporfin, a clinically approved drug with YAP inhibitory properties, was used to test the role of YAP/TAZ in reduced TGF-β signaling. Verteporfin reduced TGF-β-induced nuclear Smad2/3 accumulation and Smad3-mediated transcription in fibroblasts grown on stiff surfaces. In vivo, Verteporfin significantly reduces markers of renal fibrosis. Conclusions Soft, healthy kidney-like substrates inhibit, while stiff fibrotic-like substrates promote, pro-fibrotic TGF-β Smad signalling. Verteporfin inactivates the YAP/TAZ fibroblast mechanosensor, reduces stiffness-augmented fibroblast responses to TGF-β through blockade of Smad signalling, and may be a novel anti-fibrotic agent for CKD.

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Active immunization against the proregions of GDF9 or BMP15 alters ovulation rate and litter size in mice

Reproduction ◽

10.1530/rep-11-0336 ◽

2012 ◽

Vol 143 (2) ◽

pp. 195-201 ◽

Cited By ~ 20

Author(s):

C Joy McIntosh ◽

Steve Lawrence ◽

Peter Smith ◽

Jennifer L Juengel ◽

Kenneth P McNatty

Keyword(s):

Litter Size ◽

Transforming Growth Factor ◽

Transforming Growth Factor Β ◽

Cross Reactivity ◽

Full Length ◽

Ovulation Rate ◽

Corpora Lutea ◽

Immunization Group

The transforming growth factor β (TGFB) superfamily proteins bone morphogenetic protein 15 (BMP15) and growth differentiation factor 9 (GDF9), are essential for mammalian fertility. Recent in vitro evidence suggests that the proregions of mouse BMP15 and GDF9 interact with their mature proteins after secretion. In this study, we have actively immunized mice against these proregions to test the potential in vivo roles on fertility. Mice were immunized with either N- or C-terminus proregion peptides of BMP15 or GDF9, or a full-length GDF9 proregion protein, each conjugated to keyhole limpet hemocyanin (KLH). For each immunization group, ovaries were collected from ten mice for histology after immunization, while a further 20 mice were allowed to breed and litter sizes were counted. To link the ovulation and fertility data of these two experimental end points, mice were joined during the time period identified by histology as being the ovulatory period resulting in to the corpora lutea (CL) counted. Antibody titers in sera increased throughout the study period, with no cross-reactivity observed between BMP15 and GDF9 sera and antigens. Compared with KLH controls, mice immunized with the N-terminus BMP15 proregion peptide had ovaries with fewer CL (P<0.05) and produced smaller litters (P<0.05). In contrast, mice immunized with the full-length GDF9 proregion not only had more CL (P<0.01) but also had significantly smaller litter sizes (P<0.01). None of the treatments affected the number of antral follicles per ovary. These findings are consistent with the hypothesis that the proregions of BMP15 and GDF9, after secretion by the oocyte, have physiologically important roles in regulating ovulation rate and litter size in mice.

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