Abstract 24: Hydrogen Sulfide Potentiates Bone Marrow-derived Angiogenic Progenitor Cell-mediated Ischemic Limb Angiogenesis in Diabetic Animals

2016 ◽  
Vol 119 (suppl_1) ◽  
Author(s):  
Zhongjian Cheng ◽  
Venkata NS Garikipati ◽  
Emily Nickoloff ◽  
Chunlin Wang ◽  
David Polhemus ◽  
...  

Rationale: Critical hindlimb ischemia (CLI) represents an outcome of peripheral artery disease with a high incidence in diabetic patients. Recently, insufficient hydrogen sulfide (H 2 S) production has been implicated in cardiovascular disease. Objective: Explore the role of H 2 S in diabetes-induced bone marrow-derived angiogenic progenitor cells (BMAPC) dysfunction and its therapeutic effects on ischemic hindlimb injury of diabetes. Methods and Results: Diabetic BMAPCs from db/db mice showed decreased intracellular H 2 S production and blunted cystathionine γ-lyase (CSE) expression-an enzyme required for H 2 S generation. High glucose (HG) inhibited H 2 S production, migration and increased apoptosis of BMPAC that was rescued by H 2 S donor diallyl trisulfide (DATS) or overexpression of CSE. Administration DATS or local injection of diabetic BMAPCs overexpressing CSE significantly potentiated BMAPC-mediated blood flow recovery, capillary and arteriole formation, skeletal muscle architecture preservation, cell survival and decrease of perivascular infiltration of monocytes (CD68 + ) cells in ischemic skeletal muscle. Moreover, overexpression of CSE increased diabetic BMAPCs homing and engraftment in ischemic hindlimb. HG-impaired human cardiac microvascular endothelial cells (HCMVECs) tube formation and migration were rescued by DATS or overexpression of CSE. Mechanistically, HG increased threonine-495 phosphorylation of eNOS (eNOS-pT495) and inhibited nitric oxide (NO) production in HCMVECs which were rescued by DATS or overexpression of CSE. Silencing CSE by siRNA impaired tube formation and increased eNOS-pT495 expression in HCMVECs. Finally, HG-treated BMAPCs impaired mouse microvascular endothelial cell tube formation that was rescued by DATS. Conclusions: Our data suggests that CSE downregulation-induced H 2 S insufficient plays a critical role in diabetes-mediated BMAPC dysfunction. Administration of DATS or overexpression of CSE improves diabetic BMAPC-mediated angiogenesis/neovascularization via, at least partially, eNOS inactivation/NO reduction pathways. Our data indicate that H 2 S and overexpression of CSE in diabetic BMAPCs may open novel avenues for cell-based therapeutics of CLI in diabetic patients.

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Yingmei Feng ◽  
Miranda van Eck ◽  
Eline Van Craeyveld ◽  
Frank Jacobs ◽  
Sophie Van Linthout ◽  
...  

Background: Accelerated endothelial regeneration mediated by enhanced endothelial progenitor cell (EPC) incorporation may attenuate the development of allograft vasculopathy. Hypothesis: We investigated the hypothesis that modulation of EPC biology and attenuation of allograft vasculopathy by increased HDL cholesterol following human apo A-I (AdA-I) transfer requires scavenger receptor (SR)-BI expression in bone marrow-derived EPCs. Methods: Bone marrow transplantations with SR-BI+/+ or SR-BI−/− bone marrow were performed 4 weeks before gene transfer or saline injection. E1E3E4-deleted vectors containing a hepatocyte-specific human apo A-I expression cassette or containing no expression cassette were injected via the tail vein. Two weeks later, a common carotid artery of a female Balb/c donor mouse was transplanted paratopically into male recipient C57BL/6 mice. To analyse EPC incorporation, sex mismatch bone marrow transplantations were performed in female C57BL/6 mice and incorporated EPCs were quantified by in situ hybridization for the murine Y-chromosome. Results: Following AdA-I transfer, the number of circulating EPCs increased 2.0-fold (p<0.0001) at different time-points in C57BL/6 mice transplanted with SR-BI+/+ bone marrow but was unaltered in mice with SR-BI−/− bone marrow. The effect of HDL on EPC migration in vitro requires signaling via SR-BI and extracellular signal-regulated kinases (ERK) and is dependent on increased NO production in EPCs. Human apo A-I transfer 2 weeks before paratopic artery transplantation reduced intimal area at day 21 3.7-fold (p<0.001) in mice with SR-BI+/+ bone marrow but had no effect in mice with SR-BI−/− bone marrow. The number of CD31 positive endothelial cells lining the lumen and the number of incorporated EPCs was increased 3.0-fold (p<0.001) and 9.7-fold (p<0.001), respectively, in AdA-I treated chimeric SR-BI+/+ mice compared to control mice with SR-BI+/+ bone marrow. Endothelial regeneration and EPC incorporation was not increased after AdA-I transfer in chimeric SR-BI−/−mice. Conclusion: Human apo A-I transfer-mediated endothelial regeneration to prevent allograft vasculopathy is strictly dependent on SR-BI expressing bone marrow-derived EPCs.


2020 ◽  
Vol 48 (7) ◽  
pp. 030006052092685
Author(s):  
Yuan An ◽  
Ziquan Liu ◽  
Hui Ding ◽  
Qi Lv ◽  
Haojun Fan ◽  
...  

Objective Pulmonary microvascular endothelial cells (PMECs) exhibit specific responses in adaptation to hypoxia. However, the mechanisms regulating PMEC activities during hypoxia remain unclear. This study investigated the potential involvement of a microRNA, miR-375-3p, in the regulation of PMEC activities. Methods Primary PMECs were isolated from rats. The expression levels of miR-375-3p and Notch1 in the PMECs were detected by quantitative PCR and western blotting. Luciferase reporter assays were performed to explore the transcriptional regulation of Notch1 by miR-375-3p. The proliferation and chemotaxis of the PMECs were measured with the Cell Counting Kit-8 and Transwell invasion assays, respectively. Additionally, the capacity of hypoxia-treated PMECs for angiogenesis and inflammatory response was determined with tube formation assays and ELISA, respectively. Results The expression of miR-375-3p and Notch1 in the PMECs was significantly down-regulated and up-regulated during hypoxia, respectively. The results demonstrated that miR-375-3p directly targets Notch1 in PMECs, thereby suppressing the transcriptional expression of Notch1. It was further revealed that miR-375-3p regulates the proliferation, chemotaxis, angiogenesis, and inflammatory response of PMECs. Conclusions Our findings revealed the important role of miR-375-3p in the regulation of PMEC function and suggest the potential involvement of miR-375-3p in the development of lung diseases.


2000 ◽  
Vol 278 (4) ◽  
pp. H1163-H1167 ◽  
Author(s):  
Diane H. Munzenmaier ◽  
David R. Harder

Cerebral microvascular endothelial cells (CMVEC) form tubes when cocultured with astrocytes (AS). Therefore, it appears that AS may be important in mediating angiogenesis in the brain. We hypothesized that AS modulate CMVEC tube formation by releasing a soluble factor. Thymidine incorporation in cultured CMVEC increased 305% when incubated with 50% conditioned AS medium for 24 h [control: 52,755 ± 4,838 counts per minute (cpm) per well, conditioned 161,082 ± 12,099 cpm/well, n = 8]. Because our laboratory has previously shown that AS can produce epoxyeicosatrienoic acids (EETs), which are known mitogens, we investigated whether release of EETs by AS is responsible for tube formation in the CMVEC-AS coculture. AS were seeded on Lab-Tek slides, CMVEC were seeded on the AS the next day, and cultures were allowed to progress for another 5 days with and without cytochrome P-450 epoxygenase blockade by 17-octadecynoic acid (17-ODYA). Tube formation in cocultures receiving 17-ODYA was significantly inhibited compared with control (93.8%). These data suggest that tube formation requires the release of EETs by AS.


2008 ◽  
Vol 295 (2) ◽  
pp. H794-H800 ◽  
Author(s):  
Wei Zheng ◽  
Lance P. Christensen ◽  
Robert J. Tomanek

Mechanical stretch, an important growth stimulus, results not only from pulsatile blood flow and diastolic stretch of the ventricles [cyclic stretch (CS)] but also from tissue expansion during growth [constant static stretch (SS)]. We compared growth factor receptor expression and vasculogenic/angiogenic responses of rat coronary microvascular endothelial cells (ECs) by exposing cells to CS (10% elongation at 30 cycles/min) and SS (constant 10% elongation). Both CS and SS increased VEGF receptor (VEGF-R)2 protein levels and the extent of tube formation and branching. Moreover, both CS and SS enhanced VEGF-induced cell proliferation and tube formation, indicating that both types of stretch increase the sensitivity of ECs to VEGF. Blockade of VEGF-R2 prevented the increases in EC proliferation and aggregate tube length. However, CS but not SS enhanced EC Tie-2 protein and migration. CS affected a greater increase in tube length and branch formation than did SS. A unique finding was that SS but not CS increased VEGFR-1 in ECs. Our study is the first to distinguish between the effects of CS and SS on growth factor receptor expression and rat coronary microvascular EC proliferation, migration, and tube formation. In conclusion, EC angiogenic responses to these two types of stretch display both differences and similarities, but both CS and SS are dependent on VEGF-R2 signaling for their vasculogenic/angiogenic effects.


1996 ◽  
Vol 52 (3) ◽  
pp. 221-234 ◽  
Author(s):  
Francisco J. Candal ◽  
Shahin Rafii ◽  
Jeffery T. Parker ◽  
Edwin W. Ades ◽  
Barbara Ferris ◽  
...  

2020 ◽  
Author(s):  
Jing Mao ◽  
Jiexiong Liu ◽  
Mei Zhou ◽  
Guiqiang Wang ◽  
Xia Xiong ◽  
...  

Abstract Background: Endothelial mesenchymal transition (EndMT) is a key pathological event for vasculopathy, and is one of the early features and hallmarks of systemic scleroderma (SSc). It has been well-established that hypoxia contributes to EndMT. However, little is known about the effects of EndMT induced by hypoxia on the skin microvascular remodeling of SSc, as well as the underlying mechanism. Methods: Skin biopsy was performed for SSc patients and healthy controls, and skin tissues were collected for isobaric tags for the relative and absolute quantification (iTRAQ)-based proteomics and immunohistochemical test. Human microvascular endothelial cell line-1 (HMEC-1) cultured in hypoxic or normal conditions was treated by tamoxifen or bevacizumab. The expression of hypoxia inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF)-a, CD31, α-smooth muscle actin (α-SMA), VE-cadherin, and fibronectin were detected at both the protein and mRNA level.Results: The iTRAQ-based proteomics indicated the significantly upregulated HIF-1 signal in the skin tissues of SSc patients. The immunohistochemical results demonstrated the significant downregulation of endothelial cell (EC) marker CD31 and the distinct positive staining of interstitial cell (IC) marker α-SMA at sites that lined the vessel lumens in skin tissues of SSc. Meanwhile, the positive staining of HIF-1α, which is a key transcription factor in response to chronic hypoxia, and VEGF-a were found to be diffusely distributed in SSc skin tissues. Consistent with these observations, HMEC-1 cells cultured under hypoxic conditions exhibited a significant decrease in CD31 and VE-cadherin expression, alongside the marked increase in the expression of α-SMA and fibronectin, as well as the distinct upregulation of HIF-1α and VEGF-a, when compared with those under normal conditions. It is noteworthy that the inhibition of HIF-1α by tamoxifen effectively downregulated the hypoxic induction of VEGF-a and α-SMA, while rescuing the hypoxic suppression of CD31. In addition, the VEGF-a inhibitor bevacizumab treatment had the same effect on the hypoxic expression of α-SMA and CD31, as a tamoxifen intervention, but did not reduce HIF-1α. Conclusion: These results suggest that the HIF-1α/VEGF signaling pathway has a critical role in mediating the effect of hypoxia-induced EndMT on the skin microvascular remodeling of SSc.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 218-218 ◽  
Author(s):  
Qiu-Sha Huang ◽  
Jing Xue ◽  
Chen-Cong Wang ◽  
Ya-Zhen Qin ◽  
Lan-Ping Xu ◽  
...  

Introduction Sphingosine-1-phosphate (S1P) is now emerging as a vital lipid mediator. Activation of sphingosine kinase (SphK) produces intracellular S1P, which in turn can be secreted out of the cell and act extracellularly by binding to S1P receptors (S1PR). Recent studies suggest that the "inside-out" signaling by S1P in megakaryocytes (MKs) plays a critical role in proplatelet formation (PPF) (Blood, 2013; J EXP MED, 2012). PPF requires a profound reorganization of the MK actin and tubulin cytoskeleton. Rho GTPases which can be activated by S1P, including Rac1 and Cdc42, have been shown to be master regulators of cytoskeletal rearrangements. The pathogenesis mechanisms of immune thrombocytopenia (ITP) are not entirely understood. Our previous data indicated that impaired PPF contributed to the development of thrombocytopenia in ITP. To further explore the underlying mechanism of impaired PPF in ITP, we found that S1P-mediated microtubule reorganization is defective in PPF of ITP. All-trans retinoic acid (ATRA), which has demonstrated to be a promising option for ITP patients in our previous study (Lancet Haematology, 2017), could correct the altered microtubule reorganization and promote PPF. Methods Thirty consecutive patients with primary ITP and 20 healthy donors were enrolled in our study. MKs were isolated from bone marrow samples, and they were collected again after ITP patients received ATRA therapy. MK mRNA sequencing by microarray was used to assess the difference of gene expression between ITP and controls. Microtubule regrowth assay was performed to observe microtubule dynamic behavior. In this assay nocodazole was first used to induce complete depolymerization of microtubule network, followed by drug washout to allow microtubule regrowth over time. ATRA was added to the culture medium of MKs to determine the mechanism of ATRA in correcting impaired PPF. Additionally, ITP mice model was established to observe the therapeutic effects of ATRA in PPF. Pf4-Cre/loxP system was used to specifically knock down gene of MKs. Results S1P concentration in bone marrow from ITP patients was lower compared to healthy donors. MKs mRNA sequencing demonstrated that S1P synthetase SphK2 and S1P receptor S1PR1 gene were downregulated while S1P lyase (SPL) gene was upregulated in ITP patients, which caused abnormal S1P signaling. Furthermore, we observed that PPF capacity of MKs in patients with ITP was reduced. Pharmacological disruption of S1PR1 blocked PPF, exogenous S1P corrected impaired PPF. Collectively, deregulation of S1P signaling was associated with impaired PPF in ITP. To verify the downstream role of S1P in regulating PPF, the Rho GTPases detection of MKs revealed a decrease in Cdc42 and Rac1 levels from ITP patients. Immunofluorescence of the differentiated MKs showed that the expression and distribution of β1 tubulin were abnormal from ITP patients. Early PPs from MKs of healthy donors displayed a well-organized tubulin bundles resembling bunches of grapes. In contrast, in MKs from ITP patients, tubulin was disorganized in thick bundles. In addition, TEM analysis of the MKs showed an irregular distribution of granules, tortuous membranes and impaired proplatelet structure. In microtubule regrowth assay, MKs from ITP patients had significantly lower microtubule regrowth at 10 min post-nocodazole washout compared with controls. Together, microtubule alteration resulted in impaired PPF in ITP. We tested whether S1P pathway were required for microtubule reorganization, both SphK2-/- and S1PR1-/- mice displayed significantly reduced S1P, Cdc42 and Rac1, altered microtubule architecture and defective PPF. Taken together, abnormal S1P pathway accounted for impaired microtubule reorganization in ITP. Next, we explored the effect of ATRA on microtubules reorganization in ITP patients, our data showed that in vitro treatment with ATRA restored microtubules structure by upregulating S1P and activating Rho GTPases. In vivo studies showed that ARTA could rescue the impaired PPF in both patients and mice model with ITP. Conclusions The MKs of ITP patients displayed defective cytoskeletal reorganization regulated by S1P pathway. ATRA restored cytoskeletal structure and corrected impaired PPF by upregulating S1P and activating Rho GTPases. It sheds light on a novel mechanism of ITP pathogenesis and provides a basis for the therapeutic potential of ARTA in ITP patients. Disclosures No relevant conflicts of interest to declare.


2020 ◽  
Vol 6 (9) ◽  
pp. eaay5413 ◽  
Author(s):  
Mi-Lan Kang ◽  
Hye-Seon Kim ◽  
Jin You ◽  
Young Sik Choi ◽  
Byeong-Ju Kwon ◽  
...  

Angiogenesis is stimulated by nitric oxide (NO) production in endothelial cells (ECs). Although proangiogenic actions of human mesenchymal stem cells (hMSCs) have been extensively studied, the mechanistic role of NO in this action remains obscure. Here, we used a gelatin hydrogel that releases NO upon crosslinking by a transglutaminase reaction (“NO gel”). Then, the source-specific behaviors of bone marrow versus adipose tissue-derived hMSCs (BMSCs versus ADSCs) were monitored in the NO gels. NO inhibition resulted in significant decreases in their angiogenic activities. The NO gel induced pericyte-like characteristics in BMSCs in contrast to EC differentiation in ADSCs, as evidenced by tube stabilization versus tube formation, 3D colocalization versus 2D coformation with EC tube networks, pericyte-like wound healing versus EC-like vasculogenesis in gel plugs, and pericyte versus EC marker production. These results provide previously unidentified insights into the effects of NO in regulating hMSC source-specific angiogenic mechanisms and their therapeutic applications.


2003 ◽  
Vol 90 (11) ◽  
pp. 921-929 ◽  
Author(s):  
Yvette Hensbergen ◽  
Erna Peters ◽  
Sareena Rana ◽  
Yvonne Elderkamp ◽  
Victor van Hinsbergh ◽  
...  

SummaryThe aminopeptidase inhibitor bestatin has been shown to have anti-angiogenic effects in a number of model systems. These effects are thought to result from inhibition of CD13 activity. Because tumor angiogenesis can evolve in a fibrin-rich stroma matrix we have studied for the first time the effects of bestatin on microvascular endothelial capillary-like tube formation in a fibrin matrix. Bestatin enhanced the formation of capillary-like tubes dose-dependently. Its effects were apparent at 8 µM; the increase was 3.7-fold at 125 µM; while high concentrations (>250 µM), that were shown to have anti-angiogenic effects in other systems, caused extensive matrix degradation. Specific CD13-blocking antibodies WM15 and MY-7, and the aminopeptidase inhibitors amastatin and actinonin also enhanced capillary-like tube formation (maximally 1.5-fold), but these effects did not reach statistical significance. The effect of bestatin was not due to a change in uPAR availability because the relative involvement of the u-PA/u-PAR activity was not altered by bestatin. In view of the present findings we hypothesize that aminopeptidases other than CD13 predominantly contribute to the observed pro-angiogenic effect of bestatin in a fibrin matrix. The identification of this novel effect of bestatin is important in the light of the proposed use of bestatin as anti-angiogenic and/or anti-tumor agent.


2021 ◽  
Vol 129 (Suppl_1) ◽  
Author(s):  
Bipradas Roy ◽  
Guodong Pan ◽  
Suresh Palaniyandi

Coronary microvascular endothelial cell (CMECs) damage is implicated in diabetes-mediated heart failure with preserved ejection fraction (HFpEF). 4-hydroxy-2-nonenal (4HNE), a reactive aldehyde that is increased in diabetic heart, decreases angiogenesis in cultured mouse CMECs by decreasing the mRNA and protein levels of vascular endothelial growth factor receptor (VEGFR)2. Nuclear factor-kappa B (NF-kB), a transcription factor, was shown to transcribe VEGFR2. Thus, we presume 4HNE modulates NF-kB-mediated VEGFR2 transcription and regulates angiogenesis in CMECs. Aldehyde dehydrogenase (ALDH) 2, a mitochondrial enzyme that detoxifies 4HNE and confers cryoprotection. However, ALDH2 activity was reduced in the diabetic hearts which results in the augmentation of 4HNE-induced cardiotoxicity. Thus, we hypothesize that ALDH2 in CMECs reduces 4HNE-mediated cell signaling aberrations, and thereby, preserves coronary angiogenesis. We treated the cultured mouse CMECs with disulfiram (DSF) (2.5 μM), an ALDH2 inhibitor, alda1 (10 μM), an ALDH2 activator and prostratin (1 μM), an NF-κB activator prior to challenging the CMECs with 4HNE (75 μM). Our tube-formation angiogenesis assay revealed that pretreatment with DSF exacerbated a 4HNE-induced decrease in CMECs angiogenesis (P<0.0005 vs con and P<0.05 vs both 4HNE & DSF alone) while pretreatments with alda1 and prostratin attenuated a 4HNE-induced decrease in CMEC angiogenesis (P<0.05 vs 4HNE alone). DSF pretreatment exacerbated 4HNE mediated decrease in ALDH2 (P<0.005 vs con), phospho-IKBα (P<0.0005 vs con and P<0.05 vs both 4HNE and DSF alone), NF-κB levels, and nuclear translocation (P<0.0005 vs con and P<0.05 vs both 4HNE & DSF alone) and VEGFR2 (P<0.0005 vs con and P<0.05 vs both 4HNE and DSF alone) levels in cultured CMECs. Pretreatment with both prostratin and alda1 increased ALDH2 (P<0.0005 vs con), VEGFR2 (P<0.05 vs con) and NF-κB (P<0.005 vs con) levels in CMECs. The cardiac tissue samples of db/db mice when they manifest HFpEF showed increased 4HNE adducts, decreased NF-kB and VEGFR2 levels in CD31+ CMECs besides exhibiting low CMEC density. In conclusion, ALDH2 attenuates 4HNE-mediated decrease in coronary angiogenesis by decreasing VEGFR2 levels via low NF-κB mediated transcription.


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