Yiqi-Huoxue granule promotes angiogenesis of ischemic myocardium through miR-126/PI3K/Akt axis in endothelial cells

Phytomedicine ◽  
2021 ◽  
pp. 153713
Author(s):  
Haixia Gao ◽  
Chaojie Peng ◽  
Linke Wu ◽  
Shuibo Gao ◽  
Zhentao Wang ◽  
...  
2014 ◽  
Vol 115 (suppl_1) ◽  
Author(s):  
Susmita Sahoo ◽  
David Kim ◽  
Sol Misener ◽  
Christine E Kamide ◽  
Douglas E Vaughan ◽  
...  

Introduction: Earlier, in a first study of its kind, we have demonstrated a novel mechanism that therapeutically significant human CD34+ stem cells secrete membrane bound nano-vesicles called exosomes (CD34Exo). CD34Exo are angiogenic and constitute a critical component of the pro-angiogenic paracrine activity of the cells. Further, when transplanted locally, cell-free CD34Exo induce ischemic tissue repair in a murine hindlimb ischemia model. Here, we hypothesize that exosomes released via paracrine secretion from human CD34+ cells mediate myocardial repair by direct transfer of microRNAs to target cells in the heart. Methods and Results: When injected into mouse ischemic myocardium, cell-free CD34Exo replicated the therapeutic activity of human CD34+ cells by significantly improving ischemia (ejection fraction, 42±4 v 22±6%; capillary density, 113±7 v 66±6/HPF; fibrosis, 27±2 v 48±7%; p<0.05, n=7-12) compared with PBS control. Interestingly, confocal imaging and flow cytometry analyses of the exosomes-injected ischemic myocardial tissue revealed that CD34Exo was selectively internalized into endothelial cells and cardiomyocytes. CD34Exo, which is enriched with miR126, induced the expression of miR126 and several pro-angiogenic mRNAs in the exosomes-treated ischemic myocardium, but did not affect the endogenous synthesis of miR126. CD34Exo lacking miR126 had decreased angiogenic activity in vitro and decreased proangiogenic gene expression in vivo indicating that miR126 is important for CD34Exo function. Imaging using fluorescent miR126 confirms that CD34Exo directly transferred miR126 and possibly other yet to be identified moieties from its cargo, selectively to endothelial cells and cardiomyocytes in the ischemic heart. Conclusion: Our results reveal a novel molecular and trafficking mechanism of CD34Exo that may be responsible for intercellular transfer of genetic information such as miRNAs from human CD34+ stem cells, selectively to endothelial cells and cardiomyocytes inducing changes in gene expression, angiogenesis and myocardial recovery. Exosomes-shuttled miRNAs may signify amplification of stem cell function and may explain the therapeutic benefits associated with human CD34+ cell therapy.


2010 ◽  
Vol 70 (5) ◽  
pp. 313-321 ◽  
Author(s):  
Qiang Tan ◽  
Lugui Qiu ◽  
Guangping Li ◽  
Changhong Li ◽  
Chenghuan Zheng ◽  
...  

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Prabhu Mathiyalagan ◽  
Yaxuan Liang ◽  
David Kim ◽  
Douglas W Losordo ◽  
Roger J Hajjar ◽  
...  

Introduction: Clinical application of human CD34+ stem cells is associated with improved exercise tolerance and therapeutic angiogenesis in patients with myocardial ischemia. We reported the first description of independent therapeutic potential of CD34+ stem cell-derived exosomes (CD34Exo) to that of parent cell by mechanisms that still remain poorly understood. Hypothesis: Herein, we tested the hypothesis that CD34Exo may selectively carry non-coding RNA (ncRNA) cargo targeted for pro-angiogenic signaling and ischemic tissue repair. Methods and Results: Murine models of myocardial ischemia employed throughout the study. Cell-free CD34Exo replicated the therapeutic activity of their parent cells by significantly improving myocardial ischemia (ejection fraction, 42±4 v 22±6%; capillary density, 113±7 v 66±6/HPF; fibrosis, 27±2 v 48±7%; p<0.05, n=7-12) compared with a PBS control. Confocal imaging and flow cytometry analyses revealed that CD34Exo was selectively internalized into endothelial cells and cardiomyocytes in the CD34Exo-injected ischemic hearts. MicroRNA (miR) profiling identified several pro-angiogenic miRs including miR-126 that are selectively enriched in CD34Exo. Mice injected with CD34Exo show elevated miR-126 and several pro-angiogenic mRNAs in ischemic myocardium, however did not affect endogenous miR-126 synthesis suggestive of direct CD34Exo-mediated miR-126 transfer. Depletion of miR-126 reduced the therapeutic efficacy of CD34Exo both in vitro and in vivo indicating a critical role for miR-126. Using fluorescent-tagged miR-126, we monitored in real-time the uptake and transfer of miR-126 by endothelial cells both in vitro and in vivo. We finally provide novel insights underlying CD34Exo function in regulating endothelial proliferation through identification of novel pathways regulated by miR-126 in endothelial cells. Conclusion: Our results reveal specific CD34Exo-shuttled microRNAs and pathways regulated in the ischemic myocardium. Our work presents a molecular framework for CD34Exo mechanism and function in therapeutic angiogenesis. Precise understanding of CD34Exo mechanisms could significantly amplify the therapeutic benefits of CD34Exo in ischemic tissue regeneration and repair.


Author(s):  
D. E. Philpott ◽  
A. Takahashi

Two month, eight month and two year old rats were treated with 10 or 20 mg/kg of E. Coli endotoxin I. P. The eight month old rats proved most resistant to the endotoxin. During fixation the aorta, carotid artery, basil arartery of the brain, coronary vessels of the heart, inner surfaces of the heart chambers, heart and skeletal muscle, lung, liver, kidney, spleen, brain, retina, trachae, intestine, salivary gland, adrenal gland and gingiva were treated with ruthenium red or alcian blue to preserve the mucopolysaccharide (MPS) coating. Five, 8 and 24 hrs of endotoxin treatment produced increasingly marked capillary damage, disappearance of the MPS coating, edema, destruction of endothelial cells and damage to the basement membrane in the liver, kidney and lung.


Author(s):  
C. N. Sun ◽  
J. J. Ghidoni

Endothelial cells in longitudinal and cross sections of aortas from 3 randomly selected “normal” mongrel dogs were studied by electron microscopy. Segments of aorta were distended with cold cacodylate buffered 5% glutaraldehyde for 10 minutes prior to being cut into small, well oriented tissue blocks. After an additional 1-1/2 hour period in glutaraldehyde, the tissue blocks were well rinsed in buffer and post-fixed in OsO4. After dehydration they were embedded in a mixture of Maraglas, D.E.R. 732, and DDSA.Aldehyde fixation preserves the filamentous and tubular structures (300 Å and less) for adequate demonstration and study. The functional significance of filaments and microtubules has been recently discussed by Buckley and Porter; the precise roles of these cytoplasmic components remains problematic. Endothelial cells in canine aortas contained an abundance of both types of structures.


Author(s):  
Waykin Nopanitaya ◽  
Raeford E. Brown ◽  
Joe W. Grisham ◽  
Johnny L. Carson

Mammalian endothelial cells lining hepatic sinusoids have been found to be widely fenestrated. Previous SEM studies (1,2) have noted two general size catagories of fenestrations; large fenestrae were distributed randomly while the small type occurred in groups. These investigations also reported that large fenestrae were more numerous and larger in the endothelial cells at the afferent ends of sinusoids or around the portal areas, whereas small fenestrae were more numerous around the centrilobular portion of the hepatic lobule. It has been further suggested that under some physiologic conditions small fenestrae could fuse and subsequently become the large type, but this is, as yet, unproven.We have used a reproducible experimental model of hypoxia to study the ultrastructural alterations in sinusoidal endothelial fenestrations in order to investigate the origin of occurrence of large fenestrae.


Author(s):  
D.J.P. Ferguson ◽  
M. Virji ◽  
H. Kayhty ◽  
E.R. Moxon

Haemophilus influenzae is a human pathogen which causes meningitis in children. Systemic H. influenzae infection is largely confined to encapsulated serotype b organisms and is a major cause of meningitis in the U.K. and elsewhere. However, the pathogenesis of the disease is still poorly understood. Studies in the infant rat model, in which intranasal challenge results in bacteraemia, have shown that H. influenzae enters submucosal tissues and disseminates to the blood stream within minutes. The rapidity of these events suggests that H. influenzae penetrates both respiratory epithelial and endothelial barriers with great efficiency. It is not known whether the bacteria penetrate via the intercellular junctions, are translocated within the cells or carried across the cellular barrier in 'trojan horse' fashion within phagocytes. In the present studies, we have challenged cultured human umbilical cord_vein endothelial cells (HUVECs) with both capsulated (b+) and capsule-deficient (b-) isogenic variants of one strain of H. influenzae in order to investigate the interaction between the bacteria and HUVEC and the effect of the capsule.


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