scholarly journals Therapeutic hypothermia augments the restorative effects of PKC-β and Nox2 inhibition on an in vitro model of human blood–brain barrier

Author(s):  
Rais Reskiawan A. Kadir ◽  
Mansour Alwjwaj ◽  
Zoe McCarthy ◽  
Ulvi Bayraktutan

AbstractTo investigate whether therapeutic hypothermia augments the restorative impact of protein kinase C-β (PKC-β) and Nox2 inhibition on an in vitro model of human blood–brain barrier (BBB). Cells cultured in normoglycaemic (5.5 mM) or hyperglycaemic (25 mM, 6 to 120 h) conditions were treated with therapeutic hypothermia (35 °C) in the absence or presence of a PKC-β inhibitor (LY333531, 0.05 μM) or a Nox2 inhibitor (gp91ds-tat, 50 μM). BBB was established by co-culture of human brain microvascular endothelial cells (HBMECs) with astrocytes (HAs) and pericytes. BBB integrity and function were assessed via transendothelial electrical resistance (TEER) and paracellular flux of sodium fluorescein (NaF, 376 Da). Nox activity (lucigenin assay), superoxide anion production (cytochrome-C reduction assay), cellular proliferative capacity (wound scratch assay) and actin cytoskeletal formation (rhodamine-phalloidin staining) were assessed both in HBMECs and HAs using the specific methodologies indicated in brackets. Therapeutic hypothermia augmented the protective effects of PKC-β or Nox2 inhibition on BBB integrity and function in experimental setting of hyperglycaemia, as evidenced by increases in TEER and concomitant decreases in paracellular flux of NaF. The combinatory approaches were more effective in repairing physical damage exerted on HBMEC and HA monolayers by wound scratch and in decreasing Nox activity and superoxide anion production compared to sole treatment regimen with either agent. Similarly, the combinatory approaches were more effective in suppressing actin stress fibre formation and maintaining normal cytoskeletal structure. Therapeutic hypothermia augments the cerebral barrier-restorative capacity of agents specifically targeting PKC-β or Nox2 pathways.

1992 ◽  
Vol 262 (1) ◽  
pp. L63-L68 ◽  
Author(s):  
R. S. Oosting ◽  
J. F. Van Iwaarden ◽  
L. Van Bree ◽  
J. Verhoef ◽  
L. M. Van Golde ◽  
...  

This study focused on the question of whether exposure of surfactant protein A (SP-A) to ozone affected properties of this protein that may be involved in regulating alveolar type II cell and alveolar macrophage functions. In vitro exposure of human or canine SP-A to ozone reduced the ability of this protein to inhibit phorbol-ester induced secretion of [3H]phosphatidylcholine by alveolar type II cells in culture. Ozone-exposed human SP-A showed a decreased ability to enhance phagocytosis of herpes simplex virus and to stimulate superoxide anion production by alveolar macrophages. Experiments with elastase showed that ozone-exposed canine SP-A was more susceptible to proteolysis. A conformational change of the protein could underlie this phenomenon. Surfactant isolated from ozone-exposed rats (0.4 ppm ozone for 12 h) was also less able to stimulate superoxide anion production by alveolar macrophages than surfactant from control rats, which suggested that SP-A in vivo was also susceptible to ozone. The results of this study suggest that SP-A-alveolar cell interactions can be inhibited by ozone exposure, which may contribute to the toxicity of ozone in the lungs.


2016 ◽  
Vol 133 ◽  
pp. 100-112 ◽  
Author(s):  
Victor Llombart ◽  
Teresa García-Berrocoso ◽  
Joan Josep Bech-Serra ◽  
Alba Simats ◽  
Alejandro Bustamante ◽  
...  

2020 ◽  
Vol 104 (23) ◽  
pp. 10233-10247
Author(s):  
Charlotte Deschamps ◽  
Elora Fournier ◽  
Ophélie Uriot ◽  
Frédérique Lajoie ◽  
Cécile Verdier ◽  
...  

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
O Horvath ◽  
L Deres ◽  
K Ordog ◽  
K Bruszt ◽  
B Sumegi ◽  
...  

Abstract Introduction The deterioration of mitochondrial quality control greatly contributes to the hypertension induced cardiac remodeling and progression of heart failure. Our previous in vitro results demonstrated the mitochondrial protective effect of antioxidant BGP-15 compound in the presence of cellular stress. Purpose In our recent study we investigated the effect of BGP-15 on cardiac remodeling in spontaneously hypertensive rats (SHR) with manifested heart failure and on mitochondrial dynamics and function in cell culture model. Methods 15-month-old male SHR received 25 mg/kg/day BGP-15 (SHR-B) or placebo (SHR-C) for 18 weeks. Age matched Wistar rats (WKY) were used as normotensive control. The heart function was monitored by echocardiography. Histological preparations were made from cardiac tissue. Neonatal rat cardiomyocytes (NRCMs) were used as in vitro model. 150 μM H2O2 stress and 50 μM BGP-15 treatment was applied. Mitochondrial network was stained with MitoTracker Red. Mitochondrial membrane potential was detected using JC-1 dye, while mitochondrial function was monitored by the Agilent Seahorse XFp, Cell Mito Stress Test. In both model the cellular levels of mitochondrial dynamics proteins were measured in Western blot. To study the ultrastructure we used electron microscopy in our in vivo and in vitro model. Results Left ventricular (LV) mass and LV wall thickness were increased significantly in SHR-C group compared to the initial values (p<0.05). These parameters were decreased considerably in the SHR-B group. Ejection fraction (EF%) decreased in both SHR group although this downturn was minimal because of the treatment. Chronic high blood pressure caused higher collagen deposition in SHR-C rats that was significantly diminished in the SHR-B group. Regarding the mitochondrial function decrease in the levels of fusion proteins OPA1 and MFN2 was observed in the SHR-C group. These differences were significantly reduced by BGP-15 treatment (p<0.05). Mitigation of the level of fission protein DRP1 was however reduced by BGP-15 (p<0.05). In our cellular model, we observed that the H2O2-induced mitochondrial fragmentation was decreased by BGP-15 treatment (p<0.05). BGP-15 treatment prevented mitochondrial membrane potential fall in H2O2 stress (p<0.05). There was no significant difference in basal respiration among groups by monitoring the mitochondrial function. The maximal respiration capacity and ATP production were significantly higher in the BGP-15 treated group in comparison to the stressed group (p<0.05). Conclusion BGP-15 treatment has beneficial effects on mitochondrial dynamics and structure by promoting fusion processes. It also supports the maintenance of mitochondrial function through the preservation of the mitochondrial structure. The mitigation of remodeling processes and the preserved EF in the treated group are results at least partly of the comprehensible effects of BGP-15 on mitochondrial structure and function. Acknowledgement/Funding GINOP-2.3.2-15-2016-00049; GINOP-2.3.2-15-2016-00048; GINOP-2.3.3-15-2016-00025


2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Milene Valéria Lopes ◽  
Vânia Cristina Desoti ◽  
Angelo de Oliveira Caleare ◽  
Tânia Ueda-Nakamura ◽  
Sueli Oliveira Silva ◽  
...  

Here we demonstrate the activity of geranylgeraniol, the major bioactive constituent from seeds ofBixa orellana, againstLeishmania amazonensis. Geranylgeraniol was identified through1H and13C nuclear magnetic resonance imaging and DEPT. The compound inhibited the promastigote and intracellular amastigote forms, with IC50of11±1.0and17.5±0.7 μg/mL, respectively. This compound was also more toxic to parasites than to macrophages and did not cause lysis in human blood cells. Morphological and ultrastructural changes induced by geranylgeraniol were observed in the protozoan by electronic microscopy and included mainly mitochondria alterations and an abnormal chromatin condensation in the nucleus. These alterations were confirmed by Rh 123 and TUNEL assays. Additionally, geranylgeraniol induces an increase in superoxide anion production. Collectively, ourin vitrostudies indicate geranylgeraniol as a selective antileishmanial that appears to be mediated by apoptosis-like cell death.


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