scholarly journals Inhibitory Effect of Chinese Propolis on Phosphatidylcholine-Specific Phospholipase C Activity in Vascular Endothelial Cells

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Hongzhuan Xuan ◽  
Ruiliang Zhu ◽  
Yajing Li ◽  
Fuliang Hu

To understand the mechanisms underlying the anti-inflammatory action of Chinese propolis, we investigated its effect on the activity of phosphatidylcholine-specific phospholipase C (PC-PLC) that plays critical roles in control of vascular endothelial cell (VEC) function and inflammatory responses. Furthermore, p53 and reactive oxygen species (ROS) levels and mitochondrial membrane potential (Δψm) were investigated. Our data indicated that treatment of Chinese propolis 6.25 and 12.5 μg/ml for 12 hours increased VEC viability obviously. Exposure to Chinese propolis 6.25, 12.5, and 25 μg/ml for 6 and 12 hours significantly decreased PC-PLC activity and p53 level, and ROS levels were depressed by Chinese propolis 12.5 μg/ml and 25 μg/ml dramatically. TheΔψm of VECs was not affected by Chinese propolis at low concentration but disrupted by the propolis at 25 μg/ml significantly, which indicated that Chinese propolis depressed PC-PLC activity and the levels of p53 and ROS in VECs but disruptedΔψm at a high concentration.

1995 ◽  
Vol 74 (04) ◽  
pp. 1045-1049 ◽  
Author(s):  
P Butthep ◽  
A Bunyaratvej ◽  
Y Funahara ◽  
H Kitaguchi ◽  
S Fucharoen ◽  
...  

SummaryAn increased level of plasma thrombomodulin (TM) in α- and β- thalassaemia was demonstrated using an enzyme-linked immunosorbent assay (ELISA). Nonsplenectomized patients with β-thalassaemia/ haemoglobin E (BE) had higher levels of TM than splenectomized cases (BE-S). Patients with leg ulcers (BE-LU) were found to have the highest increase in TM level. Appearance of larger platelets in all types of thalassaemic blood was observed indicating an increase in the number of younger platelets. These data indicate that injury of vascular endothelial cells is present in thalassaemic patients.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jizhi Wu ◽  
Guangqi Zhang ◽  
Hui Xiong ◽  
Yuguang Zhang ◽  
Gang Ding ◽  
...  

AbstractOxygen therapy has been widely used in clinical practice, especially in anesthesia and emergency medicine. However, the risks of hyperoxemia caused by excessive O2 supply have not been sufficiently appreciated. Because nasal inhalation is mostly used for oxygen therapy, the pulmonary capillaries are often the first to be damaged by hyperoxia, causing many serious consequences. Nevertheless, the molecular mechanism by which hyperoxia injures pulmonary capillary endothelial cells (LMECs) has not been fully elucidated. Therefore, we systematically investigated these issues using next-generation sequencing and functional research techniques by focusing on non-coding RNAs. Our results showed that hyperoxia significantly induced apoptosis and profoundly affected the transcriptome profiles of LMECs. Hyperoxia significantly up-regulated miR-181c-5p expression, while down-regulated the expressions of NCAPG and lncRNA-DLEU2 in LMECs. Moreover, LncRNA-DLEU2 could bind complementarily to miR-181c-5p and acted as a miRNA sponge to block the inhibitory effect of miR-181c-5p on its target gene NCAPG. The down-regulation of lncRNA-DLEU2 induced by hyperoxia abrogated its inhibition of miR-181c-5p function, which together with the hyperoxia-induced upregulation of miR-181c-5p, all these significantly decreased the expression of NCAPG, resulting in apoptosis of LMECs. Our results demonstrated a ceRNA network consisting of lncRNA-DLEU2, miR-181c-5p and NCAPG, which played an important role in hyperoxia-induced apoptosis of vascular endothelial injury. Our findings will contribute to the full understanding of the harmful effects of hyperoxia and to find ways for effectively mitigating its deleterious effects.


2006 ◽  
Vol 290 (5) ◽  
pp. C1399-C1410 ◽  
Author(s):  
Helena Parfenova ◽  
Shyamali Basuroy ◽  
Sujoy Bhattacharya ◽  
Dilyara Tcheranova ◽  
Yan Qu ◽  
...  

In cerebral circulation, epileptic seizures associated with excessive release of the excitatory neurotransmitter glutamate cause endothelial injury. Heme oxygenase (HO), which metabolizes heme to a vasodilator, carbon monoxide (CO), and antioxidants, biliverdin/bilirubin, is highly expressed in cerebral microvessels as a constitutive isoform, HO-2, whereas the inducible form, HO-1, is not detectable. Using cerebral vascular endothelial cells from newborn pigs and HO-2-knockout mice, we addressed the hypotheses that 1) glutamate induces oxidative stress-related endothelial death by apoptosis, and 2) HO-1 and HO-2 are protective against glutamate cytotoxicity. In cerebral endothelial cells, glutamate (0.1–2.0 mM) increased formation of reactive oxygen species, including superoxide radicals, and induced major keystone events of apoptosis, such as NF-κB nuclear translocation, caspase-3 activation, DNA fragmentation, and cell detachment. Glutamate-induced apoptosis was greatly exacerbated in HO-2 gene-deleted murine cerebrovascular endothelial cells and in porcine cells with pharmacologically inhibited HO-2 activity. Glutamate toxicity was prevented by superoxide dismutase, suggesting apoptotic changes are oxidative stress related. When HO-1 was pharmacologically upregulated by cobalt protoporphyrin, apoptotic effects of glutamate in cerebral endothelial cells were completely prevented. Glutamate-induced reactive oxygen species production and apoptosis were blocked by a CO-releasing compound, CORM-A1 (50 μM), and by bilirubin (1 μM), consistent with the antioxidant and cytoprotective roles of the end products of HO activity. We conclude that both HO-1 and HO-2 have anti-apoptotic effects against oxidative stress-related glutamate toxicity in cerebral vascular endothelium. Although HO-1, when induced, provides powerful protection, HO-2 is an essential endogenous anti-apoptotic factor against glutamate toxicity in the cerebral vascular endothelium.


2021 ◽  
Author(s):  
Jinhai Zhai ◽  
Cuiping Yang ◽  
Tao Zhang ◽  
Dengyu Chen

Abstract BackgroundSalmonella typhimurium is a pathogenic gram-negative bacterium, which is found primarily in the intestinal lumen. It often causes diarrhea in infants and young children and leads to food poisoning, as well as septicemia and septic shock. In this study, we investigated the phenomenon and mechanism of vascular endothelial cells apoptosis induced by Salmonella typhimurium L forms, in order to recognize and control Salmonella typhimurium L-form infection.Methods The apoptosis of vascular endothelial cells at 8 hours after infection with Salmonella typhimurium L forms was determined by flow cytometric assay and fluoroscopy of Annexin V-FITC/PI staining. Caspase-9 was detected by spectrophotometer. Results Salmonella typhimurium L forms can induce apoptosis of vascular endothelial cells, with significant difference in the apoptosis rate compared with the control. Caspase-9 expression is higher than that of the control. Conclusion The ability to induce cell apoptosis of vascular endothelial cells by Salmonella typhimurium L forms may be related to mitochondria apoptosis pathway depending on Caspase-9.


2020 ◽  
Vol 40 (1) ◽  
Author(s):  
Jung-Joon Cha ◽  
Hoyeon Lee ◽  
Miyoung Kim ◽  
Juyoung Kang ◽  
Hanlim Song ◽  
...  

Abstract Vascular endothelial cells are essential to vascular function and maintenance. Dysfunction of these cells can lead to the development of cardiovascular disease or contribute to tumorigenesis. As such, the therapeutic modulation and monitoring of vascular endothelial cells are of significant clinical interest, and several endothelial-specific ligands have been developed for drug delivery and the monitoring of endothelial function. However, the application of these ligands has been limited by their high cost and tendency to induce immune responses, highlighting a need for alternate methods of targeting vascular endothelial cells. In the present study, we explore the therapeutic potential of DNA aptamers. Using cell-SELEX technology, we identified two aptamers with specific binding affinity for vascular endothelial cells and propose that these molecules show potential for use as new ligands for drug and biomarker research concerning vascular endothelial cells.


Oncotarget ◽  
2017 ◽  
Vol 8 (44) ◽  
pp. 76165-76173 ◽  
Author(s):  
Hongping Xu ◽  
Liwei Zhang ◽  
Wei Chen ◽  
Jiazhou Xu ◽  
Ruting Zhang ◽  
...  

2012 ◽  
Vol 32 (suppl_1) ◽  
Author(s):  
Taiki Kida ◽  
Yoshiki Tsubosaka ◽  
Masatoshi Hori ◽  
Hiroshi Ozaki ◽  
Takahisa Murata

Objective TGR5, a membrane-bound, G-protein-coupled receptor for bile acids, is known to be involved in regulation of energy homeostasis and inflammation. However, little is known about the function of TGR5 in vascular endothelial cells. In the present study, we examined whether TGR5 agonism represents anti-inflammatory effects in vascular endothelial cells focusing on nitric oxide (NO) production. Methods and Results In human umbilical vein endothelial cells (HUVECs), treatment with taurolithocholic acid (TLCA), which has the highest affinity to TGR5 among various bile acids, significantly reduced tumor necrosis factor (TNF)-α-induced vascular cell adhesion molecule (VCAM)-1 protein expression and adhesion of human monocytes, U937. These effects were abrogated by a NO synthase (NOS) inhibitor, N G -Monomethyl-L-arginine (L-NMMA). In bovine aortic endothelial cells (BAECs), treatment with TLCA as well as lithocholic acid, which also has high affinity to TGR5, significantly increased the NO production. In contrast, deoxycholic acid and chenodeoxycholic acid, which possess low affinity to TGR5, did not affect the NO production. Gene depletion of TGR5 by siRNA transfection abolished TLCA-induced NO production in BAECs. TLCA-induced NO production was also observed in HUVECs measured as intracellular cGMP accumulation. We next investigated the signal pathways responsible for the TLCA-induced NO production in endothelial cells. Treatment with TLCA increased endothelial NOS (eNOS) ser1177 phosphorylation in HUVECs. This response was accompanied by increased Akt ser473 phosphorylation and intracellular Ca 2+ ([Ca 2+ ] i ). Treatment with phosphoinositide 3-kinase (PI3K) inhibitor, LY294002, or blockade of calcium channel with La 3+ , significantly decreased TLCA-induced eNOS ser1177 phosphorylation and subsequent NO production. Conclusion These results indicate that TGR5 agonism can mediate anti-inflammatory responses by suppressing VCAM-1 expression and monocytes adhesion to endothelial cells. This function is dependent on NO production via Akt activation and [Ca 2+ ] i increase.


1998 ◽  
Vol 275 (3) ◽  
pp. H1011-H1015 ◽  
Author(s):  
F. Delarue ◽  
S. Daunes ◽  
R. Elhage ◽  
A. Garcia ◽  
F. Bayard ◽  
...  

The atheroprotective properties of estrogens are supported by clinical data from postmenopausal women who use estrogen replacement therapy. However, the mechanisms mediating activity remain unknown, and it has been suggested that estrogens may help to modulate endothelial permeability to atherogenic lipoproteins. In these studies we used bovine vascular endothelial cells as an in vitro model to show that estrogens were able to regulate low-density lipoprotein transport and permeability of the endothelial monolayer. Macromolecular transport was observed to be a second-order polynomial function of estrogen concentration. Moreover, this regulation was correlated with expression of heat shock protein (HSP) 25, which is known to influence fluid phase pinocytosis and cytoskeleton remodeling, thus suggesting a role for HSP 25 in the estrogenic control of transcellular permeability of the endothelium monolayer.


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