Vascular Endothelial Response Research Articles

혈관내피세포와 흰쥐 대동맥 미세혈관 발아 모델을 이용한 황금 열수추출물의 세포의 이동, 침투 및 관형성 억제 연구

혈관신생의 억제는 암과 같은 신생혈관형성 질환의 치료를 위해 유용한 접근법이다. 신생혈관형성의 핵심인자인 혈관내피세포성장인자는 신생혈관형성 질환의 치료를 위한 주요한 표적이다. 그러므로, 본 연구에서는 in vitro 분석과 ex vivo 동물 실험을 통해 황금 열수추출물의 신생혈관형성 억제효과를 연구했다. 본 연구결과에서 황금 열수추출물이 혈관내피세포성장인자에 의해 자극된 혈관내피세포에 있어 세포독성 없이 세포의 이동, 침투, 관형성을 농도 의존적으로 억제하였다. 더 나아가 황금 열수추출물은 혈관내피세포성장인자에 의해 유도된 흰쥐 대동맥 주변 미세혈관 발아를 예방하였다. 본 연구결과들은 황금 열수추출물이 신생혈관형성 억제작용이 있고, 이는 혈관내피세포성장인자에 의해 유도된 혈관신생을 억제 하는 잠재적 소재가 될 수 있음을 제안한다. Angiogenesis is essential for the pathophysiological processes of embryogenesis, tissue growth, diabetic retinopathy, psoriasis, wound healing, rheumatoid arthritis, cardiovascular diseases, and tumor growth. Inhibition of angiogenesis represents an attractive therapeutic approach for the treatment of angiogenic diseases such as cancer. However, uncontrolled angiogenesis is also necessary for tumor development and metastasis. Inhibition of vascular endothelial growth factor (VEGF) signaling, a critical factor in the induction of angiogenesis, cause robust and rapid changes in blood vessels of tumors and therefore VEGF constitutes a target for such anti-angiogenic therapy. Recently, since natural compounds pose significantly less risk of deleterious side effects than synthetic compounds, a great many natural resources have been assessed for useful substance for anti-angiogenic treatment. Here we evaluated the anti-angiogenic effects of a hot water extract of Scutellaria baicalensis (SBHWE) using in vitro assays and ex vivo animal experiments. Our results show that SBHWE dose-dependently abrogated vascular endothelial responses by inhibiting VEGF-stimulated migration and invasion as well as tube formation in a human umbilical vein endothelial cell (HUVEC) model, without cytotoxicity, as determined by a cell viability assay. Further study revealed that SBHWE prevented VEGF-induced neo-vascularization in a rat aortic ring sprouting model. Taken together, our findings reveal an anti-angiogenic activity of Scutellaria baicalensis and suggest that SBHWE is a novel candidate inhibitor of VEGF-induced angiogenesis.

Vascular Dysfunction in Pneumocystis-Associated Pulmonary Hypertension Is Related to Endothelin Response and Adrenomedullin Concentration

Pulmonary hypertension subsequent to an infectious disease can be due to vascular structural remodeling or to functional alterations within various vascular cell types. In our previous mouse model of Pneumocystis-associated pulmonary hypertension, we found that vascular remodeling was not responsible for observed increases in right ventricular pressures. Here, we report that the vascular dysfunction we observed could be explained by an enhanced response to endothelin-1 (20% greater reduction in lumen diameter, P≤0.05), corresponding to an up-regulation of similar magnitude (P≤0.05) of the endothelin A receptor in the lung tissue. This effect was potentially augmented by a decrease in production of the pulmonary vasodilator adrenomedullin of almost 70% (P≤0.05). These changes did not occur in interferon-γ knockout mice similarly treated, which do not develop pulmonary hypertension under these circumstances. Surprisingly, we did not observe any relevant changes in the vascular endothelial nitric oxide synthase vasodilatory response, which is a common potential site of inflammatory alterations to pulmonary vascular function. Our results indicate the diverse mechanisms by which inflammatory responses to prior infections can cause functionally relevant changes in vascular responses in the lung, promoting the development of pulmonary hypertension.

Severe Endothelial Damage in Chronic Kidney Disease Patients Prior to Haemodialysis Vascular Access Surgery.

Hemodialysis as an efficient therapy for advanced CKD is the most used treatment modality all over the world. Even though primary AVF is widely accepted as a best permanent vascular access in hemodialysis patients, up to 60% of all fistulas fail to mature. The pathogenesis of early fistula failure is not very well understood. Many general and local factors are involved: patient's age, sex, primary renal disease, small vessel's diameter, presence of accessory veins, prior venipunctures, surgical skill, genetics, etc. Histological investigations have confirmed the neointimal venous hyperplasia as a major pathological finding in stenotic lesions of AVF failure, due to local inflammation, oxidative stress and migration and proliferation of myofibroblasts, fibroblasts and endothelial cells. A total of 89 patients with stadium 4-5 of CKD are involved in the study. A typical radio-cephalic AVF is created in all patients. Part of the fistula vein was taken for histological, immunohistochemical (Vimentin, TGF β and KI67) and morphometric analysis. Appriopriate statistical method was applied. Up to 80% of the patients showed some degree of endothelial changes at the time of creation of AVF, among them 19 pts with substantial intimal hyperplasia, 51 with medial hypertrophy and 19 pts with normal histology. Almost two thirds of the patients did not have expression of TGFβ. More than 95% had some expression of Vimentin. None of the patients had expression of the marker KI 67. Medial hypertrophy is predominant preexisting pathohistological lesion prior the AVF creation, despite the presence of neointimal hyperplasia. The absence of TGFβ expression in majority of our patients could suggest that inflammation and oxidative stress are developing later, after vascular access surgery. The dominant cells within the stenosis in the veins are myofibroblasts. Their increased presence maybe a reason why some patients are prone to developing venous endothelial changes as a results of exaggerated vascular endothelial response to the effect of uremia, hypertension and other insults.

Abstract A22: Identification of novel tumor derived factors that inhibit angiogenesis

Abstract Background: Cell-cell communication in the tumor micro-environment drive tumor growth and facilitate neovessel recruitment from the adjacent vasculature. The present study was designed to identify novel cancer derived factors that modulate the vascular endothelial response in a paracrine manner. Methods: An array of cancer cell lines from multiple tissue types (Panc1; HepG2; LnCap; Skmel; Hep3B; PL45; SCC25; CaCo2; PaCa2; SKBR3) were grown under normoxic or hypoxic (1% oxygen) conditions for a total of 20 different conditions. After 48 hours, conditioned media was collected and filtered prior to testing on endothelial cells. The effects of the conditioned media on endothelial apoptosis, proliferation and tube formation were investigated. In tandem with these endothelial cell fate assays, the proteomic profile of these 20 conditions was profiled and assessed using the Berg Interrogative Biology™ platform. Results & Discussion: Our results reveal that conditioned media from all cancer cells tested can alter endothelial cell apoptosis, proliferation rate and tube formation in 3D matrigel assays i.e. critical cell fate decisions that enable formation of nascent vessel formation. As predicted, the predominant effect of tumor-derived conditioned media on endothelial apoptosis was a protective anti-apoptotic effect, with the discernable exception of normoxic Panc1 derived media. An unexpected finding was the general anti-proliferative effects of tumor-derived conditioned media on endothelial cell growth, with the exception of Hep2G, LnCap and PaCa2 cell derived media. Using a media fractionation strategy and Interrogative Biology™, we identified several endothelial anti-apoptotic candidates from Panc1 cells within a unique molecular weight range. Upon application of ASO gene knockdown in Panc1 cells, these targets were verified for apoptotic and proliferation effects on vascular endothelial cells. Conclusion: Specific factors that determine paracrine cell-cell interaction in the tumor microenvironment have been identified and validated employing Berg Interrogative Biology™. The technology presented herein represents a viable platform for identifying clinically relevant biomarkers and factors that alter cancer angiogenesis. Citation Format: Tony E. Walshe, Justin Bourdelais, Arleide Lee, Rakibou Ouro-Djobo, Vivek Vishnudas, Rangaprasad Sarangarajan, Niven Narain. Identification of novel tumor derived factors that inhibit angiogenesis. [abstract]. In: Proceedings of the AACR Special Conference: Tumor Angiogenesis and Vascular Normalization: Bench to Bedside to Biomarkers; Mar 5-8, 2015; Orlando, FL. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl):Abstract nr A22.

Advanced glycation end-products induced VEGF production and inflammatory responses in human synoviocytes via RAGE-NF-κB pathway activation.

Aging and diabetes are known to be the major cause to affect the progression of osteoarthritis (OA). Advanced glycation end products (AGEs) have been observed to accumulate in various organs especially in joint tissue and do damage to the joint tissue during aging and diabetes. Synovial angiogenesis and inflammation are observed across the full range of OA severity. The signaling pathway of AGEs on vascular endothelial growth factor (VEGF) production and inflammatory responses in synoviocytes are still unclear. Here, we investigated the role of receptor for AGEs (RAGE) and the signaling pathway involved in AGEs-induced VEGF production and inflammatory responses in human synoviocytes. Human synoviocytes were cultured and treated with AGEs (25-100 µg/ml). AGEs significantly induced the protein expressions of cyclooxygenase-2 (COX-2) and VEGF and the productions of prostaglandin-E2 (PGE2), VEGF, interleukin-6 (IL-6), and metalloproteinase-13 (MMP-13) in human synoviocytes in a dose-dependent manner. Moreover, AGEs markedly activated the phosphorylations of IκB kinase (IKK)α/β, IκBα, and nuclear factor (NF)-κB-p65 proteins in human synoviocytes in a time-dependent manner. Treatment with neutralizing antibody for RAGE statistically significantly decreased the AGEs-induced increase in COX-2, VEGF, PGE2, IL-6, and MMP13 and AGEs-activated NF-κB pathway activation. Taken together, these findings indicate that AGEs are capable of inducing VEGF production and inflammatory responses via RAGE-NF-κB pathway activation in human synoviocytes. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:791-800, 2016.

Human Papillomavirus-Negative Pharyngeal Cancer.

Human papillomavirus-negative head and neck squamous cell carcinoma (HNSCC) carries a poor prognosis, and despite optimal treatment with chemoradiotherapy to the limit of tolerance, many patients will relapse. A number of methods for intensifying treatment of HNSCC have been investigated, leading to the current standards of care. Novel agents targeting tumor cell and stromal signaling, DNA damage response, and immune system are now reaching clinical trials in combination with chemoradiotherapy. In this review, we discuss the evidence for the current treatment of locally advanced human papillomavirus-negative HNSCC, as well as investigational therapies, such as hypoxia modification, molecular targeting of epidermal growth factor receptor family, vascular endothelial growth factor receptor or DNA damage response proteins in combination with radiation therapy.

Calycosin-7-O-β-D-glucoside promotes oxidative stress-induced cytoskeleton reorganization through integrin-linked kinase signaling pathway in vascular endothelial cells.

BackgroundDysfunction of vascular endothelium is implicated in many pathological situations. Cytoskeleton plays an importance role in vascular endothelial permeability barrier and inflammatory response. Many Chinese herbs have the endothelial protective effect, of which, “Astragalus membranaceus” is a highly valued herb for treatment of cardiovascular and renal diseases in traditional Chinese medicine, In this study, we tested whether calycosin-7-O-β-D-glucoside (Calycosin), a main effective monomer component of “Astragalus membranaceus”, could protect endothelial cells from bacterial endotoxin (LPS)-induced cell injury.MethodsEndothelial cell injury was induced by exposing human umbilical vein endothelial cells (HUVECs) to LPS. The effects of calycosin on LPS-induced changes in cell viability, apoptosis rate, cell migration, nitric oxide synthase (NOS), generationof intracellular reactive oxygen species (ROS) and cytoskeleton organization were determined. Microarray assay was employed to screen the possible gene expression change. Based on the results of microarray assay, the expression profile of genes involved in Rho/ROCK pathway and AKT pathway were further evaluated with quantitative real-time RT-PCR or western blot methods.ResultsCalycosin improved cell viability, suppressed apoptosis and protected the cells from LPS-induced reduction in cell migration and generation of ROS, protein level of NOS at a comparable magnitude to that of Y27632 and valsartan. Similar to Y27632 and valsartan, Calycosin, also neutralized LPS-induced actomyosin contraction and vinculin protein aggregation. Microarray assay, real-time PCR and western blot results revealed that LPS induced expression of FN, ITG A5, RhoA, PI3K (or PIP2 in western blotting), FAK, VEGF and VEGF R2, and inhibited expression of MLCP. We believed multiple pathways involved in the regulation of calycosin on HUVECs. Calycosin are considered to be able to activate MLCP through promoting the generation of NO, decreasing PMLC, suppressing the cytoskeleton remodeling caused by activation of Rho/ROCK pathway and inhibiting AKT pathway by decreasing VEGF, VEGF R2 and PI3K level.ConclusionCalycosin protected HUVEC from LPS-induced endothelial injury, possibly through suppression of Rho/ROCK pathway and regulation of AKT pathway.

Citreoviridin Enhances Atherogenesis in Hypercholesterolemic ApoE-Deficient Mice via Upregulating Inflammation and Endothelial Dysfunction.

Vascular endothelial dysfunction and inflammatory response are early events during initiation and progression of atherosclerosis. In vitro studies have described that CIT markedly upregulates expressions of ICAM-1 and VCAM-1 of endothelial cells, which result from NF-κB activation induced by CIT. In order to determine whether it plays a role in atherogenesis in vivo, we conducted the study to investigate the effects of CIT on atherosclerotic plaque development and inflammatory response in apolipoprotein E deficient (apoE-/-) mice. Five-week-old apoE-/- mice were fed high-fat diets and treated with CIT for 15 weeks, followed by assay of atherosclerotic lesions. Nitric oxide (NO), vascular endothelial growth factor (VEGF) and endothelin-1 (ET-1) were detected in serum. Levels of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), VEGF, and ET-1 in plaque areas of artery walls were examined. NF-κB p65 expression and NF-κB activation in aorta also were assessed. CIT treatment significantly augmented atherosclerotic plaques and increased expressions of ICAM-1, VCAM-1, VEGF and ET-1 in aorta. Mechanistic studies showed that activation of NF-κB was significantly elevated by CIT treatment, indicating the effect of CIT on atherosclerosis may be regulated by activation of NF-κB.

CpG signalling, H2A.Z/H3 acetylation and microRNA-mediated deferred self-attenuation orchestrate foetal NOS3 expression.

BackgroundAn adverse intrauterine environment leads to permanent physiological changes including vascular tone regulation, potentially influencing the risk for adult vascular diseases. We therefore aimed to monitor responsive NOS3 expression in human umbilical artery endothelial cells (HUAEC) and to study the underlying epigenetic signatures involved in its regulation.ResultsNOS3 and STAT3 mRNA levels were elevated in HUAEC of patients who suffered from placental insufficiency. 5-hydroxymethylcytosine, H3K9ac and Histone 2A (H2A).Zac at the NOS3 transcription start site directly correlated with NOS3 mRNA levels. Concomitantly, we observed entangled histone acetylation patterns and NOS3 response upon hypoxic conditions in vitro. Knock-down of either NOS3 or STAT3 by RNAi provided evidence for a functional NOS3/STAT3 relationship. Moreover, we recognized massive turnover of Stat3 at a discrete binding site in the NOS3 promoter. Interestingly, induced hyperacetylation resulted in short-termed increase of NOS3 mRNA followed by deferred decrease indicating that NOS3 expression could become self-attenuated by co-expressed intronic 27 nt-ncRNA. Reporter assay results and phylogenetic analyses enabled us to propose a novel model for STAT3-3′-UTR targeting by this 27-nt-ncRNA.ConclusionsAn adverse intrauterine environment leads to adaptive changes of NOS3 expression. Apparently, a rapid NOS3 self-limiting response upon ectopic triggers co-exists with longer termed expression changes in response to placental insufficiency involving differential epigenetic signatures. Their persistence might contribute to impaired vascular endothelial response and consequently increase the risk of cardiovascular disease later in life.Electronic supplementary materialThe online version of this article (doi:10.1186/s13148-014-0042-4) contains supplementary material, which is available to authorized users.

Three phase bone scan interpretation based upon vascular endothelial response.

Objectives:A new method of interpretation of Three Phase Bone Scan (TPBS) scan based upon the normal physiological vascular endothelial related response.Materials and Methods:Fifty cases of TPBS were evaluated. Thirteen were normal. In remaining 37 positive studies, 20 showed localized hyperemic response. All localized hyperemic responses except one with vascular endothelial dysfunction were without infection (95.0%). Infection could be ruled out in absence of generalized massive flow and pool response. All 17 cases with generalized massive hyperemic response had infection, consistent with infection or CRPS/RSD. Micro-bacterial or histological confirmation of infection was obtained in 11 cases. All 11 cases with confirmed infection showed generalized massive hyperemic response (100.0%). Two were CRPS/RSD and 2 cases were of cellulitis (100.0%). Among remaining 2, one refused surgery and other was lost to follow-up. Additionally, 20 published cases in the literature of osteomyelitis were also analyzed. Nineteen cases of bone and joint infection, (osteomyelitis/arthritis/cellulitis) except one with endothelial dysfunction showed generalized massive increased flow and pool response (95.0%). All published cases of osteomyelitis in the literature showed generalized massive hyperemic response (100.0%).Results:The data clearly indicated that 100% of the cases of bone infection (osteomyelitis/arthritis/cellulitis) and cases of CRPS/RSD showed generalized massive flow and pool pattern. Infection could be ruled out in absence of generalized massive flow and pool response. All 100% published cases of osteomyelitis in the literature showed positive vascular endothelial response.Conclusion:By incorporating the concept of vascular endothelial related response causing massive vasodilatation in infection, the interpretation of the TPBS can be more précised as it is based upon the normal physiology. Larger studies are recommended.

Predictive and Prognostic Significance of Vascular Endothelial Growth Factor (VEGF) and Response to VAD Protocol of Chemotherapy In Multiple Myeloma Patients

Predictive and Prognostic Significance of Vascular Endothelial Growth Factor (VEGF) and Response to VAD Protocol of Chemotherapy In Multiple Myeloma Patients

Individualized early goal-directed therapy in systemic inflammation: is full utilization of preload reserve the optimal strategy?

In severe acute pancreatitis, the administration of fluids in the presence of positive fluid responsiveness is associated with better outcome when compared to guiding therapy on central venous pressure. We compared the effects of such consequent maximization of stroke volume index with a regime using individual values of stroke volume index assessed prior to severe acute pancreatitis induction as therapeutic hemodynamic goals. Prospective, randomized animal study. University animal research laboratory. Thirty domestic pigs. After randomization, fluid resuscitation was started 2 hours after severe acute pancreatitis induction and continued for 6 hours according to the respective treatment algorithms. In the control group, fluid therapy was directed by maximizing stroke volume index, and in the study group, stroke volume index assessed prior to severe acute pancreatitis served as primary hemodynamic goal. Within the first 6 hours of severe acute pancreatitis, the study group received a total of 1,935.8 ± 540.7 mL of fluids compared with 3,462.8 ± 828.2 mL in the control group (p < 0.001). Pancreatic tissue oxygenation did not differ significantly between both groups. Vascular endothelial function, measured by flow-mediated vasodilation before and 6 hours after severe acute pancreatitis induction, revealed less impairment in the study group after treatment interval (-90.76% [study group] vs -130.89% [control group]; p = 0.046). Further, lower levels of heparan sulfate (3.41 ± 5.6 pg/mL [study group] vs 43.67 ± 46.61 pg/mL [control group]; p = 0.032) and interleukin 6 (32.18 ± 8.81 pg/mL [study group] vs 77.76 ± 56.86 pg/mL [control group]; p = 0.021) were found in the study group compared with control group. Histopathological examination of the pancreatic head and corpus at day 7 revealed less edema for the study group compared with the control group (1.82 ± 0.87 [study group] vs 2.89 ± 0.33 [control group, pancreatic head]; p = 0.03; 2.2 ± 0.92 [study group] vs 2.91 ± 0.3 [control group, pancreatic corpus]; p = 0.025). Individualized optimization of intravascular fluid status during the early course of severe acute pancreatitis, compared with a treatment strategy of maximizing stroke volume by fluid loading, leads to less vascular endothelial damage, pancreatic edema, and inflammatory response.

Abstract 174: Remote Ischemic Preconditioning Improves Digital Vascular Endothelial Function and Enhances Circulating Nitric Oxide Formation in Healthy Volunteers

Background: Remote ischemic preconditioning (RIPC) induced by brief episodes of ischemia of the limb protects against organ damage by ischemia-reperfusion. It has been reported that RIPC improves endothelial function of the forearm in normal subjects and patients with coronary artery disease. However, the digital vascular endothelial response to RIPC has not been determined in healthy volunteers. Methods: This study was performed to examine effect of RIPC on fingertip digital vascular endothelial function by using endothelial pulse amplitude tonometry (EndoPAT) device and alteration in circulating nitric oxide(NO) level in peripheral blood. Ten healthy adult subjects (5 men, 5 women, mean age 25.2 years) had 3 cycles of 5 min ischemia alternating with 5 min reperfusion of the forearm. Another 10 healthy volunteers (6 men, 4 women, mean age 26.2 years) were used as the control group of sham and the cuff was inflated for 3 times at 10 mmHg for 5 minutes with 5-minute intervals. Fingertip digital vascular endothelial function of the ipsilateral arm was measured prior to first ischemia, 3h and 6h after the last episode of ischemia. Blood samples were taken from the contralateral arm prior to first ischemia, 3h and 6h after the last episode of ischemia. Results: Fingertip digital vascular endothelial function was significantly increase in 3h and 6h after the last RIPC intervention compared with the baseline condition(p&lt;0.05). In parallel the RIPC stimulus increased circulating NO formation(p&lt;0.05). There is a close association between finger vascular endothelial function and NO formation(p&lt;0.05). Conclusion: The present findings demonstrate for the first time that transient RIPC contributes to improvement of digital vascular endothelial function and increase in circulating NO production in healthy volunteers. Our data provide a novel evidence to support that RIPC might gain even wider application not only in disease but also in health.

Abstract 3463: Identification and characterization of novel cancer cell derived factors that dictate vascular endothelial cell biology

Abstract Cell-cell communication in the tumor microenvironment drives tumor growth and facilitates neovessel recruitment from the adjacent vasculature. The aim of these experiments were to identify novel cancer derived factors that modulate the vascular endothelial response in a paracrine manner. An array of cancer cell lines from multiple tissue types (Panc1; Hep2G; LnCap; Skmel; Hep3B; PL45; SCC25; CaCo2; PaCa2; SKBR3) were grown under normoxic or hypoxic (1% oxygen) conditions for a total of 20 conditions. After 48 hours, conditioned media was collected and filtered prior to testing on endothelial cells. The effects of these media on endothelial apoptosis, proliferation and tube formation were investigated. In tandem with these endothelial cell fate assays, the proteomic and lipidomic profile of these 20 conditions were profiled and assessed using the Berg Interrogative Biology™ platform. Our results reveal that conditioned media from all cancer cells tested can alter endothelial cell apoptosis, proliferation rate and tube formation in 3D matrigel assays i.e. critical cell fate decisions that enable formation of nascent vessel formation. Interestingly, the predominant effect of tumor-derived conditioned media on endothelial apoptosis was a protective anti-apoptotic effect, with the discernable exception of normoxic Panc1 derived media. An unexpected finding was the general anti-proliferative effects of tumor-derived conditioned media on endothelial cell growth, with the exception of Hep2G, LnCap and PaCa2 cell derived media. Using a media fractionation strategy and the Berg Interrogative Biology™ platform, we identified several endothelial anti-apoptotic candidates from Panc1 cells within a unique molecular weight range. Upon application of ASO gene knockdown in Panc1 cells, these targets were verified for apoptotic and proliferation effects on vascular endothelial cells.Specific factors that determine paracrine cell-cell interaction in the tumor microenvironment have been identified and validated using the Berg Interrogative Biology™ platform. Citation Format: Tony Walshe, Justin J. Bourdelais, Arleide Lee, Rakib Ouro-Djobo, Vivek Vishnudas, Michael Kiebish, Rangaprasad Sarangarajan, Niven R. Narain. Identification and characterization of novel cancer cell derived factors that dictate vascular endothelial cell biology. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3463. doi:10.1158/1538-7445.AM2014-3463

Erythropoietin action in stress response, tissue maintenance and metabolism.

Erythropoietin (EPO) regulation of red blood cell production and its induction at reduced oxygen tension provides for the important erythropoietic response to ischemic stress. The cloning and production of recombinant human EPO has led to its clinical use in patients with anemia for two and half decades and has facilitated studies of EPO action. Reports of animal and cell models of ischemic stress in vitro and injury suggest potential EPO benefit beyond red blood cell production including vascular endothelial response to increase nitric oxide production, which facilitates oxygen delivery to brain, heart and other non-hematopoietic tissues. This review discusses these and other reports of EPO action beyond red blood cell production, including EPO response affecting metabolism and obesity in animal models. Observations of EPO activity in cell and animal model systems, including mice with tissue specific deletion of EPO receptor (EpoR), suggest the potential for EPO response in metabolism and disease.

Size-dependent biological effects on vascular endothelial cells induced by different particulate matters.

The contribution of particles to cardiovascular mortality and morbidity has been enlightened by epidemiologic and experimental studies. However, adverse biological effects of the particles with different sizes on cardiovascular cells have not been well recognized. In this study, sub-cultured human umbilical vein endothelial cells (HUVECs) were exposed to increasing concentrations of pure quartz particles (DQ) of three sizes (DQPM1, <1 μm; DQPM3-5, 3-5 μm; DQPM5, 5 μm) and carbon black particles of two sizes (CB0.1, <0.1 μm; CB1, <1 μm) for 24 h. Cytotoxicity was estimated by measuring the activity of lactate dehydrogenase (LDH) and cell viability. Nitric oxide (NO) generation and cytokines (TNF-α and IL-1β) releases were analyzed by using NO assay and enzyme-linked immunoabsorbent assay (ELISA), respectively. It was found that both particles induced adverse biological effects on HUVECs in a dose-dependent manner. The size of particle directly influenced the biological activity. For quartz, the smaller particles induced stronger cytotoxicity and higher levels of cytokine responses than those particles of big size. For carbon black particles, CB0.1 was more capable of inducing adverse responses on HUVECs than CB1 only at lower particle concentrations, in contrast to those at higher concentrations. Meanwhile, our data also revealed that quartz particles performed stronger cell damage and produced higher levels of TNF-α than carbon black particles, even if particles size was similar. In conclusion, particle size as well as particle composition should be both considered in assessing vascular endothelial cells injury and inflammation responses induced by particles.

Proteasomal degradation of O-GlcNAc transferase elevates hypoxia-induced vascular endothelial inflammatory response†.

Hypoxia induces vascular inflammation by a mechanism not fully understood. Emerging evidence implicates O-GlcNAc transferase (OGT) in inflammation. This study explored the role of OGT in hypoxia-induced vascular endothelial inflammatory response. Hypoxia was either induced (1% O2 chamber) or mimicked by exposure to hypoxia-mimetic agents in cultured endothelial cells. Hypoxia increased hypoxia-inducible factor (HIF-1α) and inflammatory response (gene and protein expression of interleukin (IL)-6, IL-8, monocyte chemoattractant protein-1, and E-selectin) but, surprisingly, reduced OGT protein (not mRNA) levels. Hypoxia-mimetic CoCl2 failed to reduce OGT when proteasome inhibitors were present, suggesting proteasome involvement. Indeed, CoCl2 enhanced 26S proteasome functionality evidenced by diminished reporter (Ub(G76V)-GFP) proteins in proteasome reporter cells, likely due to increased chymotrypsin-like activities. Mechanistically, β-TrCP1 mediated OGT degradation, since siRNA ablation of this E3 ubiquitin ligase stabilized OGT. Administration of the oxidative stress inhibitors reversed both proteasome activation and OGT degradation. Furthermore, up-regulation of OGT by stabilization, overexpression, or activation mitigated CoCl2-elicited inflammatory response. These observations were recapitulated in a mouse (C57BL/6J) model mimicking hypoxia, in which lung tissues presented higher levels of HIF-1α, proteasome activity, and inflammatory response, but lower levels of OGT (n = 5/group, hypoxia vs. normoxia, P < 0.05). However, administration of an activator of OGT (glucosamine: 1 mg/g/day, vehicle: saline, ip, 5 days) abolished the up-regulation of proteasome activity and inflammatory response (n = 5/group, the treated vs. untreated hypoxia groups, P < 0.05). 26S proteasome-mediated OGT reduction contributed to hypoxia-induced vascular endothelial inflammatory response. Modulation of OGT may represent a new approach to treat diseases characterized by hypoxic inflammation.

Effect on the expression of VEGF and HIF‐1 alpha in atherosclerosis rat myocardial with oral HSP60 (618.8)

Objective to study the effect on the expression of vascular endothelial growth factor (VEGF) and hypoxia inducing factor ‐ 1 alpha (HIF ‐ 1 alpha) in atherosclerosis(AS) rat myocardial with oral heat shock protein 60 (HSP60) .Methods 40 four weeks male SD rats, weight 100 + 10 g, were randomly divided into 4 groups: the healthy control group (group C), atherosclerosis group (AS group), oral HSP60 group before building AS model (H1 group), oral HSP60 group after building AS model (H2 group), 10 rats in each group. AS model was made by high fat feed. At 180 days age, the rats were executed after obtaining the rats blood and myocardial. The gene and protein expression of rats myocardial VEGF and HIF ‐ 1 alpha were detected by reverse transcription ‐ polymerase chain reaction (RT‐PCR) and immunohistochemical.Results The VEGF gene expression in rats myocardial of group C, AS group, H1group and H2 group respectively are 0.374±0.039, 0.869±0.049, 0.443±0.031 and 0.583±0.041; the gene expression of HIF ‐ 1 alpha respectively are 0.455±0.056, 0.936±0.034, 0.553±0.048 and 0.625±0.063; the protein expression of VEGF respectively are 4.46±0.47, 9.17±0.58, 5.28±0.37 and 8.14±0.49; the protein expression of HIF ‐ 1 alpha respectively are 5.77±0.71,13.87±0.43,7.01±0.61and 0.45±0.80.Conclusion The gene and protein expression of VEGF and HIF ‐ 1 alpha in atherosclerotic rats myocardial enhanced compared with normal control group. Oral HSP60 can reduce the gene and protein expression of VEGF and HIF ‐ 1 alpha in myocardial, and reduce the degree of myocardial ischemia anoxic injury and vascular endothelial inflammatory response. Moreover, the earlier oral, the better results.Grant Funding Source: Supported by the Science and technology development projects in Shanxi Province (No. 2011004)

Simvastatin combined with antioxidant attenuates the cerebral vascular endothelial inflammatory response in a rat traumatic brain injury.

Traumatic brain injury (TBI) leads to important and deleterious neuroinflammation, as evidenced by indicators such as edema, cytokine production, induction of nitric oxide synthase, and leukocyte infiltration. After TBI, cerebral vascular endothelial cells play a crucial role in the pathogenesis of inflammation. In our previous study, we proved that simvastatin could attenuate cerebral vascular endothelial inflammatory response in a rat traumatic brain injury. This purpose of this study was to determine whether simvastatin combined with an antioxidant could produce the same effect or greater and to examine affected surrogate biomarkers for the neuroinflammation after traumatic brain injury in rat. In our study, cortical contusions were induced, and the effect of acute and continuous treatment of simvastatin and vitamin C on behavior and inflammation in adult rats following experimental TBI was evaluated. The results demonstrated that simvastatin combined with an antioxidant could provide neuroprotection and it may be attributed to a dampening of cerebral vascular endothelial inflammatory response.

Oscillatory shear stress-induced arginase activity may explain reduced exhaled nitric oxide levels after vest chest physiotherapy in cystic fibrosis.

The well-executed study by Sisson et al. [1] demonstrates the potential of vest chest physiotherapy (VCPT) in improving airway clearance in cystic fibrosis (CF) patients. The authors point out that they observed a nonsignificant tendency towards higher exhaled nitric oxide (NOx) levels in CF compared to healthy control subjects which is at odds with previous findings of lower NOx in CF [2, 3]. Contrary to Sisson et al.'s hypothesis, VCPT in CF patients reduced rather than increased NOx. The authors discuss this unexpected finding with regard to increased cellular NO utilisation and distal airway mucous barriers to NO diffusion. An alternative explanation involves NO synthetase (NOS) and arginase activity in airway epithelial cells. Both enzymes compete for L-arginine as substrate and imbalances in activity levels are believed to be important in the pathogenesis of airway inflammation and hyperreactivity [4]. Arginase converts L-arginine into L-ornithine and urea, effectively modulating NOS activity, proinflammatory oxidant species generation, and airway remodelling [5]. Impaired lung function in CF is likely associated with reduced NO-mediated bronchodilation arising from low levels of L-arginine, impaired NOS expression, and increased arginase activity [6, 7]. Elevated systemic arginase and concomitantly reduced L-arginine levels were observed in acutely hospitalised CF patients and normalised after successful treatment [8]. Increased arginase activity, in addition to limiting NO production, also contributes to CF lung pathology through downstream products [9], is associated with Pseudomonas infection, and inversely related to lung function [10]. Arginase is moreover thought to play a role in the pathogenesis of other lung diseases like asthma and chronic obstructive pulmonary diseases [11, 12]. Recently, inhaled L-arginine was demonstrated to be a safe and potentially beneficial treatment approach in CF [13]. A possible mechanism to explain Sisson et al.'s [1] surprising finding of lower NOx after VCPT may be an increase in arginase activity through oscillatory mechanical stimulation of lung epithelial cells. Several studies in animal and cell models have demonstrated that specific patterns of mechanical stimulation can induce vascular endothelial arginase expression and activity. For instance, oscillatory shear stress induced stronger arginase activation than application of unidirectional shear force in porcine [14] and ApoE-deficient murine carotid artery segments [15]. An in vitro study showed that cyclic stretching of vascular smooth muscle cells upregulated arginase mRNA expression and enzyme activity whilst inhibiting NOS [16]. The VCPT device used in Sisson et al.'s [1] study produced oscillatory inflation/deflation cycles at a rate of 10–15 Hz throughout 20-minute treatment sessions. Thus, a possible explanation for reduced exhaled NO could be oscillatory shear stress-induced upregulation of arginase activity and associated inhibition of NOS. Whilst the observed vascular endothelial response in arginase activity to shear forces remains to be demonstrated for airway epithelial cells, the suggested link provides a plausible theory to account for Sisson et al.'s intriguing findings.