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Hyperglycemia linked to diabetes results in endothelial dysfunction. In the present work, we comprehensively characterized effects of short-term hyperglycemia induced by administration of an insulin receptor antagonist, the S961 peptide, on endothelium and perivascular adipose tissue (PVAT) in mice. Endothelial function of the thoracic and abdominal aorta in 12-week-old male C57Bl/6Jrj mice treated for two weeks with S961 infusion via osmotic pumps was assessed in vivo using magnetic resonance imaging and ex vivo by detection of nitric oxide (NO) production using electron paramagnetic resonance spectroscopy. Additional methods were used to analyze PVAT, aortic segments and endothelial-specific plasma biomarkers. Systemic disruption of insulin signaling resulted in severe impairment of NO-dependent endothelial function and a loss of vasoprotective function of PVAT affecting the thoracic as well as abdominal parts of the aorta, however a fall in adiponectin expression and decreased uncoupling protein 1-positive area were more pronounced in the thoracic aorta. Results suggest that dysfunctional PVAT contributes to vascular pathology induced by altered insulin signaling in diabetes, in the absence of fat overload and obesity.

// Marta Smeda 1 , Anna Kieronska 1 , Bartosz Proniewski 1 , Agnieszka Jasztal 1 , Anna Selmi 1 , Krystyna Wandzel 1 , Agnieszka Zakrzewska 1 , Tomasz Wojcik 1 , Kamil Przyborowski 1 , Katarzyna Derszniak 1 , Marta Stojak 1 , Dawid Kaczor 1 , Elzbieta Buczek 1 , Cezary Watala 2 , Joanna Wietrzyk 3 and Stefan Chlopicki 1, 4 1 Jagiellonian Centre for Experimental Therapeutics, Jagiellonian University, Bobrzynskiego 14, Krakow 30-348, Poland 2 Department of Haemostasis and Haemostatic Disorders, Medical University of Lodz, Kosciuszki 4, Lodz 90-419, Poland 3 Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Department of Experimental Oncology, Rudolfa Weigla 4, Wroclaw 53-114, Poland 4 Chair of Pharmacology, Jagiellonian University, Medical College, Grzegorzecka 16, Krakow 31-531, Poland Correspondence to: Stefan Chlopicki, email: stefan.chlopicki@jcet.eu Keywords: mouse breast cancer; vascular mimicry; platelet inhibition; aspirin; clopidogrel Received: November 01, 2017 Accepted: February 25, 2018 Published: April 03, 2018 ABSTRACT Platelet inhibition has been considered an effective strategy for combating cancer metastasis and compromising disease malignancy although recent clinical data provided evidence that long-term platelet inhibition might increase incidence of cancer deaths in initially cancer-free patients. In the present study we demonstrated that dual anti-platelet therapy based on aspirin and clopidogrel (ASA+Cl), a routine regiment in cardiovascular patients, when given to cancer-bearing mice injected orthotopically with 4T1 breast cancer cells, promoted progression of the disease and reduced mice survival in association with induction of vascular mimicry (VM) in primary tumour. In contrast, treatment with ASA+Cl or platelet depletion did reduce pulmonary metastasis in mice, if 4T1 cells were injected intravenously. In conclusion, distinct platelet-dependent mechanisms inhibited by ASA+Cl treatment promoted cancer malignancy and VM in the presence of primary tumour and afforded protection against pulmonary metastasis in the absence of primary tumour. In view of our data, long-term inhibition of platelet function by dual anti-platelet therapy (ASA+Cl) might pose a hazard when applied to a patient with undiagnosed and untreated malignant cancer prone to undergo VM.

Raman spectroscopy is a label free, versatile, simple and fast method that is increasingly used to detect pathological changes in the cells and tissues that could be useful in medical diagnostics. In this work, we tested the hypothesis that Raman spectroscopy may serve to detect endothelial dysfunction in murine models of lifestyle diseases associated with endothelial dysfunction. For that purpose, we analysed spectra from ex vivo vessels taken from mice with diabetes, hypertension and cancer metastasis. We extracted 50–70 random, single spectra, recorded in 0.2 s, from endothelium of mice with diseases and respective control animals and subjected them to hierarchical cluster analysis. Independently on the sample preparation protocol, very good discrimination was obtained for three-tested murine models, i.e. diabetes, hypertension and cancer metastasis. Obtained sensitivity and specificity parameters were between 93% and 96% (with the exception of sensitivity in the diabetes model equalled to 88%). Our results show that single, random spectra of endothelium, recorded in less than a second, contains enough information on biochemical content of the endothelium to detect endothelial dysfunction. Furthermore, we demonstrated that biochemical profile of the endothelial dysfunction in diabetes, hypertension or cancer metastasis differs with a very high specificity and sensitivity. This conclusion can be a good starting point for the development of in vivo fast diagnostic methodology of endothelium in the future. Copyright © 2016 John Wiley & Sons, Ltd.

It was recently reported in the murine model of metastatic breast cancer (4T1) that tumor progression and development of metastasis is associated with systemic endothelial dysfunction characterized by impaired nitric oxide (NO) production. Using Raman 3D confocal imaging with the analysis of the individual layers of the vascular wall combined with AFM endothelial surface imaging, we demonstrated that metastasis-induced systemic endothelial dysfunction resulted in distinct chemical changes in the endothelium of the aorta. These changes, manifested as a significant increase in the protein content (18 %) and a slight decrease in the lipid content (4 %), were limited to the endothelium and did not occur in the deeper layers of the vascular wall. The altered lipid to protein ratio in the endothelium, although more pronounced in the fixed vascular wall, was also observed in the freshly isolated unfixed vascular wall samples in the aqueous environment (12 and 7 % change of protein and lipid content, respectively). Our results support the finding that the metastasis induces systemic endothelial dysfunction that may contribute to cancer progression. Graphical Abstract Schematic illustration of methodology of sample preparation and measurement Electronic supplementary material The online version of this article (doi:10.1007/s00216-016-9436-9) contains supplementary material, which is available to authorized users.

14 p.-6 fig., Aims: A soluble form of endoglin (sEng) was proposed to participate in the induction of endothelial dysfunction in small blood vessels. Here, we tested the hypothesis that high levels of sEng combined with a high-fat diet induce endothelial dysfunction in an atherosclerosis-prone aorta., Methods and results: Six-month-old female and male transgenic mice overexpressing human sEng (Sol-Eng+) with low (Sol-Eng+low) or high (Sol-Eng+high) levels of plasma sEng were fed a high-fat rodent diet containing 1.25% cholesterol and 40% fat for 3 months. The plasma cholesterol and mouse sEng levels did not differ in the Sol-Eng+high and Sol-Eng+low mice. The expression of proinflammatory (P-selectin, ICAM-1, pNFκB and COX-2) and oxidative-stress-related markers (HO-1, NOX-1 and NOX-2) in the aortas of Sol-Eng+high female mice was significantly higher than in Sol-Eng+low female mice. Endothelium-dependent vasodilatation induced by acetylcholine was preserved better in the Sol-Eng+ high female mice than in the Sol-Eng+low female mice., Conclusion: These results suggest that high concentrations of sEng in plasma in combination with a high-fat diet induce the simultaneous activation of proinflammatory, pro-oxidative and vasoprotective mechanisms in mice aorta and the balance of these biological processes determines whether the final endothelial phenotype is adaptive or maladaptive., The work was supported by grants from Czech Science Foundation GACR No. GA15-24015S, the Grant Agency of Charles University in Prague No. 1284214/C, No. 1158413C and SVV/2016/260293, the European Regional Development Fund under the Innovative Economy Program of the European Union (grant coordinated by JCET-UJ, No. POIG.01.01.02-00-069/09), the Ministerio de Economia y Competitividad of Spain (SAF2013-43421-R to C.B. and SAF2013-45784-R to J.M.L.-N.), the Junta de Castilla y Leon (GR100 to J.M.L.-N.), CIBERER (to C.B.) and Red de Investigación Cooperativa en Enfermedades Renales (REDINREN, RD12/0021/0032 to J.M.L.-N.). CIBERER and REDINREN are initiatives of the Instituto de Salud Carlos III of Spain supported by European Regional Development Funds (FEDER). The Cardiovascular Phenotyping Unit of the University of Salamanca received the support of FEDER.

Although anthracycline antibiotics have been successfully used for nearly half a century in the treatment of various malignancies, their use is limited by their cardiac and vascular toxicities, and the mechanisms of these toxicities are still not entirely clear. Herein, we comprehensively characterized cytotoxic effects of two structurally related anthracyclines, doxorubicin and daunorubicin. In nanomolar concentrations, both drugs induced DNA damage and increased nuclear area that were associated with their accumulation in the nucleus (doxorubicin ⩾50 nM and daunorubicin ⩾25 nM) as evidence by Raman microspectroscopy at 3820-4245 cm(-1). At low micromolar concentrations, doxorubicin (⩾5 μM) and daunorubicin (⩾1 μM) increased the generation of reactive oxygen species, decreased intracellular reduced glutathione, induced an alteration in endothelial elasticity and caused a reorganization of the F-actin cytoskeleton. In isolated mouse aortic rings, doxorubicin (⩾50 μM) was less potent than daunorubicin (⩾5 μM) in impairing the endothelium-dependent response. In summary, using a comprehensive endothelial profiling approach, we demonstrated clear-cut differences in the potencies to induce endotheliotoxic responses for two structurally similar chemotherapeutics, at a nuclear, cytosolic and membrane levels. Furthermore, our results suggest that the differences in the endothelial toxicities of doxorubicin and daunorubicin are linked to differences in their nuclear accumulation and the DNA damage-triggered response of the endothelium.

Diabetes increases the risk of pulmonary hypertension and is associated with alterations in pulmonary vascular function. Still, it is not clear whether alterations in the phenotype of pulmonary endothelium induced by diabetes are distinct, as compared to peripheral endothelium. In the present work, we characterized differences between diabetic complications in the lung and aorta in db/db mice with advanced diabetes. Male, 20-week-old db/db mice displayed increased HbA1c and glucose concentration compatible with advanced diabetes. Diabetic lungs had signs of mild fibrosis, and pulmonary endothelium displayed significantly ultrastructural changes. In the isolated, perfused lung from db/db mice, filtration coefficient (Kf,c) and contractile response to TXA2 analogue were enhanced, while endothelial NO-dependent modulation of pulmonary response to hypoxic ventilation and cumulative production of NO2− were impaired, with no changes in immunostaining for eNOS expression. In turn, 6-keto-PGF1α release from the isolated lung from db/db mice was increased, as well as immunostaining of thrombomodulin (CD141). In contrast to the lung, NO-dependent, acetylcholine-induced vasodilation, ionophore-stimulated NO2− generation, and production of 6-keto-PGF1α were all impaired in aortic rings from db/db mice. Although eNOS immunostaining was not changed, that of CD141 was clearly lowered. Interestingly, diabetes-induced nitration of proteins in aorta was higher than that in the lungs. In summary, diabetes induced marked ultrastructural changes in pulmonary endothelium that were associated with the increased permeability of pulmonary microcirculation, impaired NO-dependent vascular function, with compensatory increase in PGI2 production, and increased CD141 expression. In contrast, endothelial dysfunction in the aorta was featured by impaired NO-, PGI2-dependent function and diminished CD141 expression.

Background Patients with cancer develop endothelial dysfunction and subsequently display a higher risk of cardiovascular events. The aim of the present work was to examine changes in nitric oxide (NO)- and prostacyclin (PGI2)-dependent endothelial function in the systemic conduit artery (aorta), in relation to the formation of lung metastases and to local and systemic inflammation in a murine orthotopic model of metastatic breast cancer. Methods BALB/c female mice were orthotopically inoculated with 4T1 breast cancer cells. Development of lung metastases, lung inflammation, changes in blood count, systemic inflammatory response (e.g. SAA, SAP and IL-6), as well as changes in NO- and PGI2-dependent endothelial function in the aorta, were examined 2, 4, 5 and 6 weeks following cancer cell transplantation. Results As early as 2 weeks following transplantation of breast cancer cells, in the early metastatic stage, lungs displayed histopathological signs of inflammation, NO production was impaired and nitrosylhemoglobin concentration in plasma was decreased. After 4 to 6 weeks, along with metastatic development, progressive leukocytosis and systemic inflammation (as seen through increased SAA, SAP, haptoglobin and IL-6 plasma concentrations) were observed. Six weeks following cancer cell inoculation, but not earlier, endothelial dysfunction in aorta was detected; this involved a decrease in basal NO production and a decrease in NO-dependent vasodilatation, that was associated with a compensatory increase in cyclooxygenase-2 (COX-2)- derived PGI2 production. Conclusions In 4 T1 metastatic breast cancer in mice early pulmonary metastasis was correlated with lung inflammation, with an early decrease in pulmonary as well as systemic NO availability. Late metastasis was associated with robust, cancer-related, systemic inflammation and impairment of NO-dependent endothelial function in the aorta that was associated with compensatory upregulation of the COX-2-derived PGI2 pathway.

The role of nitric oxide (•NO) in metastatic cancer progression has not been fully explained. In the present work we characterized the development of •NO deficiency in the lung and examined changes in •NO and prostacyclin (PGI2)-dependent endothelial function in the systemic conduit artery (aorta), in relation to the progression of 4T1 metastatic breast cancer injected orthotopically in Balb/c mice. Furthermore, orthotopic and intravenous models of 4T1 metastatic cancer in mice were used to study the differential effects of L-NAME-induced •NO deficiency on the primary tumor and the metastatic burden. •NO was assessed in isolated aorta and lungs using EPR spin-trapping and chemiluminescence, while NOx in blood were measured using either EPR, chemiluminescence or Griess reaction. Early pulmonary metastasis was correlated with lung inflammation. Pulmonary endothelial function and systemic •NO availability in 4T1 breast cancer-bearing mice were compromised prior to the development of pulmonary metastasis,preceding the onset of its phenotypic switch toward a mesenchymal phenotype (EndMT). Late metastasis was associated with robust, cancer-related, systemic inflammation and impairment of NO-dependent endothelial function in the aorta that was associated with compensatory upregulation of the COX-2-derived PGI2 pathway. L-NAME-induced •NO-deficiency showed that •NO plays a major role in the primary tumor development, but it is not the key mediator responsible for the regulation of cancer cell extravasation to the lungs in our model, despite clear-cut •NO-deficiency in the lung, reflected by a fall in systemic •NO bioavailability, both occurring early in the pre-metastatic phase.

Aim: Increased risk of pulmonary hypertension and not clear response of pulmonary endothelium to diabetes were reasons to compare nitric oxide (NO) and PGI-dependent function in pulmonary and systemic circulation in diabetes type II. Methods: In fasted db mice (male, 20 weeks) we compared the function of pulmonary (isolated perfused lung-IPL) and aortic endothelium (wire myograph). It was supported by determination of nitrite(NO 2 - )/nitrate(NO 3 - ), PGI production, immunostaining (IMS) and western blot. Results: In diabetic IPL NO-dependent modulation of hypoxic pulmonary vasoconstriction was impaired but filtration coefficient increased; response to U46619 was enhanced; cumulative generation of NO 2 - was decreased (NO 3 - , basals not changed) but 6-keto-PGF 1α increased. In diabetic lungs CD141 but not eNOS IMS was increased, fibrosis of parenchyma was weak and ultrastructural endothelial changes pronounced. In diabetic aortic rings impairment of acetylcholine-induced vasodilation, ionophore-stimulated NO 2 - (not basal) and 6-keto-PGF 1α production were observed. CD141 but not eNOS IMS was lower. In diabetes general protein nitration and nitration of PGI synthase (PGIS) were substantially increased in aorta but not in the lungs. Conclusions: Advanced diabetes affects pulmonary circulation resulting in (1) increased permeability of microcirculation and vasoreactivity; (2) impairment of NO-dependent vascular function paralleled with aorta; (3) increased PGI production contrasted with aorta; (4) weak nitration of pulmonary PGIS as oppose to systemic. In the diabetic lungs impairment of NO-dependent function was not alongside production of PGI; it may be due to the relative resistance to non-enzymatic nitration of PGIS.

Angiotensin-converting enzyme inhibitors (ACE-I) display vasoprotective activity and represent the cornerstone in the treatment of cardiovascular diseases. In this study, we tested whether Fourier transform infrared (FTIR)-based analysis of blood plasma is sensitive to detect vasoprotective effects of treatment with perindopril including reversal of endothelial dysfunction in diabetes. For this purpose, plasma samples were collected from untreated db/db mice, db/db mice treated with 2 or 10 mg/kg perindopril and db+ mice. The effect of perindopril on endothelial function was examined in ex vivo aortic rings; 10 mg/kg but not 2 mg/kg of perindopril reversed endothelial dysfunction. In plasma of db/db mice, the balance between conformations of plasma proteins was noted, and treatment with perindopril at a high dose but not at a low dose reversed this effect. This was revealed by amide II/amide I ratio attributed to increased β-sheet formation. Spectral markers at 3010, 1520/1238 cm−1, representative for unsaturation degree of lipids and phosphorylation of tyrosine, respectively, were also affected by perindopril treatment. In conclusion, although metabolic abnormalities associated with type 2 diabetes mellitus such as hypertriglyceridemia and hyperglycemia strongly affected spectral FTIR profile of diabetic plasma, we identified FTIR features that seem to be associated with the vasoprotective activity of ACE-I.

This study assessed the effects of individual conjugated linoleic acid isomers, c9t11-CLA and t10c12-CLA, on nonalcoholic fatty liver disease (NAFLD) and systemic endothelial dysfunction in rats fed for four weeks with control or high-fructose diet. The high-fructose diet hampered body weight gain (without influencing food intake), increased liver weight and glycogen storage in hepatocytes, upregulated expression of fatty acid synthase (FAS) and stearoyl-CoA desaturase-1 (SCD-1), and increased saturated fatty acid (SFA) content in the liver. Both CLA isomers prevented excessive accumulation of glycogen in the liver. Specifically, t10c12-CLA decreased concentration of serum triacylglycerols and LDL + VLDL cholesterol, increased HDL cholesterol, and affected liver lipid content and fatty acid composition by downregulation of liver SCD-1 and FAS expression. In turn, the c9t11-CLA decreased LDL+VLDL cholesterol in the control group and downregulated liver expression of FAS without significant effects on liver weight, lipid content, and fatty acid composition. In summary, feeding rats with a high-fructose diet resulted in increased liver glycogen storage, indicating the induction of gluconeogenesis despite simultaneous upregulation of genes involved inde novolipogenesis. Although both CLA isomers (c9t11 and t10c12) display hepatoprotective activity, the hypolipemic action of the t10c12-CLA isomer proved to be more pronounced than that of c9t11-CLA.

It has been repeatedly shown that regular aerobic exercise exerts beneficial effects on incidence and progression of cancer. However, the data regarding effects of exercise on metastatic dissemination remain conflicting. Therefore, in the present study the possible preventive effects of voluntary wheel running on primary tumor growth and metastases formation in the model of spontaneous pulmonary metastasis were analyzed after orthotopic injection of 4T1 breast cancer cells into mammary fat pads of female Balb/C mice. This study identified that in the mice injected with 4T1 breast cancer cells and running on the wheels (4T1 ex) the volume and size of the primary tumor were not affected, but the number of secondary nodules formed in the lungs was significantly increased compared to their sedentary counterparts (4T1 sed). This effect was associated with decreased NO production in the isolated aorta of exercising mice (4T1 ex), suggesting deterioration of endothelial function that was associated with lower platelet count without their overactivation. This was evidenced by comparable selectin P, active GPIIb/IIIa expression, fibrinogen and vWF binding on the platelet surface. In conclusion, voluntary wheel running appeared to impair, rather than improve endothelial function, and to promote, but not decrease metastasis in the murine orthotopic model of metastatic breast cancer. These results call for revising the notion of the persistent beneficial effects of voluntary exercise on breast cancer progression, though further studies are needed to elucidate mechanisms involved in pro-metastatic effects of voluntary exercise.