Protective Effects of Dexmedetomidine on Hippocampal Neurons in Rats Anesthetized with Sevoflurane

2022 ◽  
Vol 12 (1) ◽  
pp. 1-9
Author(s):  
Li Chen ◽  
Tao Tang ◽  
Xin Zheng ◽  
Ying Xiong
Keyword(s):  
Signaling Pathways ◽  
Hippocampal Neuron ◽  
Oxygen Flow ◽  
Control Group ◽  
Rt Pcr ◽  
Bdnf Expression ◽  
Functional Changes ◽  
Downstream Signaling ◽  
Induced Apoptosis ◽  
Neuron Apoptosis

To explore effects of dexmedetomidine (Dex) on cognitive function and hippocampal neuronal apoptosis in rats anesthetized with sevoflurane (Sevo), and regulation of brain-derived neurotrophic factor (BDNF) and its downstream signaling. 30 Sprague-Dawley (SD) rats were randomly divided into control group inhaled 29% concentration oxygen), Sevo group (2 L/min oxygen flow +1.5% Sevo), Dex+Sevo group (after injection of 20 μg/kg Dex, treated with 2L/min oxygen flow+1.5% Sevo). Haematoxylin and eosin (HE) staining and Nissl’s staining were adopted to detect morphological and functional changes in hippocampus of rats. Apoptosis was detected by immunofluorescence, BDNF expression was detected by immunohistochemistry. Reverse transcription PCR (RT-PCR) was conducted to detect mRNA expression of key proteins in downstream signaling of BDNF. The results showed that Sevo induced apoptosis of hippocampus neurons, while Dex improved Sevo induced apoptosis. In contrast to the control, the positive expression of BDNF in hippocampus of Sevo group was notably decreased (P < 0.05), and that of Dex+Sevo group was notably higher in contrast to Sevo group (P < 0.05). Signaling pathways of MAPK, PI3K-Akt, and Ras were predicted by String software as the downstream pathways of BDNF. RT-PCR results showed that these 3 signaling pathways were involved in Dex improving Sevo-induced cognitive impairment and hippocampal neuron apoptosis. In conclusion, Dex could improve cognitive dysfunction and hippocampal neuron apoptosis in rats induced by Sevo, and the mechanism was related to upregulation of BDNF expression and activation of pathways of MAPK, PI3K-Akt, and Ras.

scholarly journals Molecular Mechanism of ATF6α/S1P/S2P Signaling Pathway in Hippocampal Neuron Apoptosis in SPS Rats

2021 ◽  
Author(s):  
liang han ◽  
Yan hao Xu ◽  
Yu xiu Shi
Keyword(s):  
Mrna Expression ◽  
Hippocampal Neurons ◽  
Hippocampal Neuron ◽  
Control Group ◽  
Tunel Staining ◽  
Apoptosis Rate ◽  
Memory Disorder ◽  
Caspase 12 ◽  
Induced Apoptosis ◽  
Neuron Apoptosis

Abstract Apoptosis of hippocampal neurons is one of the mechanisms of hippocampal atrophy in posttraumatic stress disorder (PTSD), and it is also one of the important reasons of memory disorder in PTSD patients. The endoplasmic reticulum stress (ERS) mediated by activated transcription factor 6α(ATF6α)/site 1 protease (S1P)/S2P is involved in cell apoptosis, but it is not clear whether it is involved in hippocampal neuron apoptosis caused by PTSD. The PTSD rat model was constructed by the single-prolonged stress (SPS) method. The experiment was divided into two parts: (1) Control group, SPS 1d group, SPS 7d group, SPS 14d group. (2) Control group, SPS 7d group, SPS 7d+AEBSF group, control+AEBSF group. 4-(2-Aminoethyl) benzenesulfonyl fluoride hydrochloride (AEBSF) is an ATF6α pathway inhibitor. The expression of ATF6α, glucose regulated protein (GRP78), S1P, S2, C/EBP homologous protein (CHOP), caspase-12 protein and mRNA in the hippocampus of PTSD rats were detected by immunohistochemistry, Western blotting and qRT-PCR. The apoptosis of hippocampal neurons was detected by TUNEL staining. In experiment 1, the protein and mRNA expression of ATF6α, GRP78 increased gradually in SPS 1d group and SPS 7d group, but decreased in SPS 14d group(P<0.01). In experiment 2, compared with the control group, the protein and mRNA expression of ATF6α, GRP78, S1P, S2P, CHOP, caspase-12 and apoptosis rate were significantly increased in SPS 7d group(P<0.01). However, the protein and mRNA expression of ATF6α, GRP78, S1P, S2P, CHOP, caspase-12 and apoptosis rate were significantly decreased after AEBSF pretreatment(P<0.01). SPS induces apoptosis of hippocampal neurons by activating ERS mediated by ATF6α, suggesting that ERS-induced apoptosis is involved in the occurrence of PTSD.

Monoclonal Antibody Against ROR1 in Chronic Lymphocytic Leukemia Cells Induced Apoptosis Via PI3-Kinase/AKT/CREB Pathway

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 1769-1769
Author(s):  
Amir Hossein Daneshmanesh ◽  
Mohammad Hojjat-Farsangi ◽  
Asa Sandin ◽  
Abdul Salam Khan ◽  
Ali Moshfegh ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Western Blot ◽  
Signaling Pathways ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Pi3 Kinase ◽  
Signaling Proteins ◽  
Downstream Signaling ◽  
Induced Apoptosis ◽  
Creb Pathway

Abstract Abstract 1769 Background: Phosphoinositide 3-kinase (PI3K)/AKT cascade regulates cell survival, proliferation and differentiation in a variety of cells. In CLL cells PI3K pathway is constitutively activated leading to AKT activation and phosphorylation of cAMP response element-binding protein (CREB). CREB is a transcription factor overexpressed and constitutively phosphorylated in a variety of cancers and seems to have a role in tumor pathobiology. There is a great need to develop novel strategies for targeted therapy in CLL. Monoclonal antibodies (mAbs) specifically targeting leukemic cells might be a rewarding approach. ROR1 is a type I transmembrane receptor tyrosine kinase belonging to one of the twenty families of receptor tyrosine kinases (RTKs). ROR1 is overexpressed on CLL cells but not in white blood cells of healthy donors. ROR1 is constitutively phosphorylated in CLL and siRNA transfection induced apoptosis. We have developed a unique anti-ROR1 mAb directed against CRD (cysteine-rich domain) of the extracellular region of ROR1 capable of inducing direct apoptosis of primary CLL cells. Our anti-CRD mAb induced dephosphorylation of the ROR1 molecule. Aims: To study the apoptotic effect of an anti-ROR1 CRD mAb and effects on downstream signaling pathways involved in CLL, specially the PI3-kinase/AKT/CREB pathway using primary CLL cells. Methods: Using a peptide-based mouse mAb generation method we produced several mAbs against the three extracellular domains of ROR1. In the current study we used one of the best anti-ROR1 antibodies, an anti-CRD mAb raised against the CRD region of ROR1 (Daneshmanesh et al., Leukemia. 2012 Jun;26(6):1348-55). Flow cytometry was used for surface staining of ROR1. Primary CLL cells were incubated with the anti-ROR1 CRD mAb and apoptosis was detected by the MTT assay and Annexin V/propidium iodide (flow cytometry) methods in a 24 h assay. Antibody untreated and treated cell lysates were prepared and subjected to Western blot analysis for identification of signaling molecules involved in apoptosis induced by the anti-ROR1 CRD mAb. We analysed total and phosphorylated levels of the following signaling proteins: AKT, p-AKT, PI3K, p-PI3K, CREB, p-CREB, ERK, p-ERK, PKC and p-PKC. Phosphoproteins were measured before incubation with the mAb and after 20 min-2 h. Results: ROR1 surface expression was detected on 80–85% of the CLL cells. The frequency of apoptotic cells induced by the anti-CRD mAb was in the range of 45–50% which is in accordance with our previous reports (see above). Time kinetics experiments using anti-ROR1 CRD mAb incubated with primary CLL cells revealed dephosphorylation of ROR1 downstream signaling molecules. We analysed the following molecules known to be involved in CLL: PKC, PI3-kinase and ERK1/2. After co-culturing CLL cells with the anti-ROR1 CRD mAb, Western blot analysis showed decreased level of phosphorylated AKT in treated compared to untreated samples. No changes in the phosphorylation levels of ERK1/2 and PKC proteins were seen. Furthermore, we analysed the PI3-kinase protein which is upstream of AKT, and noticed that in CLL cells treated with the anti-ROR1 CRD mAb, the phosphorylation intensity of PI3-kinase p85 isoform has decreased but not p55 isoforrn. Moreover, we also studied the CREB phosphorylation in treated and untreated CLL samples and detected dephosphorylation of CREB in treated as compared to untreated samples. Conclusion: Incubation of CLL cells with an anti-ROR1 CRD mAb induced apoptosis of primary CLL cells. Apoptosis was preceded by dephosphorylation within 2 h of PI3-kinase, AKT and CREB proteins indicating deactivation of these signaling proteins by the anti-ROR1 mab. In untreated CLL cells no effect on phosphorylation of these proteins was noted. Furthermore our ROR1 mAb did not dephosphorylate PKC or ERK. Our data may suggest that activation of CREB molecule might occur via the PI3K/AKT pathway and may be a survival signal in CLL cells associated with the aberrant expression of ROR1. The constitutive phosphorylation of PKC and ERK1/2 seen in CLL might not be related to the overexpression of ROR1. Further studies are warranted for a better understanding of signaling pathways associated with ROR1 and the downstream signaling effects of ROR1 targeting drugs. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Warfarin Treatment Alters Gas6 and Protein S Activity and Their Downstream Signaling Pathways in Brain, and Stimulates Microglial Activity (P24-002-19)

2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Guylaine Ferland ◽  
Pierre Allaire ◽  
Bouchra Ouliass
Keyword(s):  
Signaling Pathways ◽  
Tyrosine Kinases ◽  
Protein S ◽  
Convincing Evidence ◽  
Bdnf Expression ◽  
Behavioral Impairment ◽  
Downstream Signaling ◽  
Funding Sources ◽  
Male Wistar Rats

Abstract Objectives There is now convincing evidence that vitamin K (VK) has important actions in the nervous system and cognition. Two VK-dependent proteins are closely linked to the brain namely Gas6 and protein S (PS). Functionally, both proteins are ligands for receptors of tyrosine kinases Tyro3, Axl, and Mer. In vitro, Gas6 and PS have been shown to possess pro-survival activity towards neurons and glia through stimulation of the extracellular signal-regulated (ERK) and serine-threonine (Akt) kinases pathways. In a previous study, targeted depletion of VK in brain induced by warfarin (W) treatment, a VK antagonist, resulted in cognitive and behavioral impairment. In the present study, we aimed to characterize the role of Gas6 and PS and their signaling pathways in W-treated rats fed or not with supplemental menaquinone-4 (MK-4), the principal K vitamer in brain. Methods Male Wistar rats (n = 5–7/gp) were randomly allocated to a AIN-93 based diet containing 750 mcg phylloquinone (K1)/kg/d supplemented with 100 mg MK-4/kg/d (MK-4) or not (N). After one week, rats were administered 14 mg W/kg/d (in drinking water) and subcutaneous K1 (94 mg/kg), 3X/wk, for 9 wks. [Subcutaneous K1 treatment is required to maintain the coagulation function]. A control gp (C) treated with normal water and injected with saline was also included. Gas6, PS, pAkt, pERK as well as brain-derived neurotrophic factor (BDNF) and microglial CD11b/c protein, were assessed in hippocampus (HPP), frontal cortex (FC) and striatum (STR), three regions involved in cognition, by immunoblotting. Group difference were tested by one-way ANOVA. Results Impact of W treatment was particularly marked in HPP, rats from N group showing decreased Gas6, PS and ERK activity as well as decreased BDNF expression, compared to C gp. Further, rats from N group presented increased expression of CD11bc, a marker of inflammation (all P < 0.05). Supplementing the diet with MK-4 normalized PS activity and BDNF and CD11bc expression in HPP, Gas6 and pERK in CF, and pAkt in STR (all P < 0.05). Conclusions Results indicate that W treatment as used in the present study alters Gas6 and PS activity and their downstream signaling pathways, and stimulates microglial activity. Supplementing the diet with large amounts of MK-4 normalized much of the phenotype. Funding Sources Study funded by CIHR.

scholarly journals Fangjing decoction relieves febrile seizures-induced hippocampal neuron apoptosis in rats via regulating the Akt/mTOR pathway

2018 ◽  
Vol 38 (5) ◽  
Author(s):  
Xian-ke Xu ◽  
Sun-yao Wang ◽  
Ying Chen ◽  
Lu Zhan ◽  
Zheng-yang Shao ◽  
...  
Keyword(s):  
Hippocampal Neurons ◽  
Hippocampal Neuron ◽  
Febrile Seizures ◽  
Mtor Pathway ◽  
Mtor Signaling ◽  
Rat Hippocampus ◽  
Control Group ◽  
Protective Effects ◽  
Bax Protein ◽  
Neuron Apoptosis

Background: Fangjing decoction is a Traditional Chinese Medicine that exhibits anticonvulsive effects in treating febrile seizures (FS). Its action mechanism and the regulation on Akt/mammalian target of rapamycin (mTOR) pathway were revealed in the present study. Methods: FS model was established in Sprague–Dawley rats with or without Fangjing decoction treatment. On day 5, following initiation of drug treatment, seizures were monitored. Hippocampal neuron apoptosis was assessed using terminal dUTP nick end-labeling method. The levels of Bax, protein kinase B (Akt), phospho-Akt (p-Akt), mTOR, and p-mTOR proteins were analyzed using Western blotting. The content of hippocampal γ-aminobutyric acid (GABA) was measured by using ELISA assay. Results: Compared with the control group (n=8), Fangjing decoction effectively shortened escape latency and duration of FS and decreased the frequency of FS in rats (n=8). Concomitantly, the apoptosis of hippocampal neurons, as well as Bax protein levels were also decreased in FS rats which were treated with Fangjing decoction. In addition, the Akt/mTOR signaling was found to be activated in rat hippocampus following FS, as evidenced by increased p-Akt and p-mTOR, while Fangjing decoction could inhibit the activation of Akt/mTOR signaling. Furthermore, the low GABA content in rat hippocampus following FS was significantly elevated by Fangjing decoction treatment. More importantly, SC79, a specific activator for Akt, apparently attenuated the protective effects of Fangjing decoction on FS rats. Conclusion: These results suggest that Fangjing decoction protects the hippocampal neurons from apoptosis by inactivating Akt/mTOR pathway, which may contribute to mitigating FS-induced brain injury.

scholarly journals Antrocin Sensitizes Prostate Cancer Cells to Radiotherapy through Inhibiting PI3K/AKT and MAPK Signaling Pathways

Cancers ◽  
2018 ◽  
Vol 11 (1) ◽  
pp. 34 ◽  
Author(s):  
Yu-An Chen ◽  
David T. W. Tzeng ◽  
Yi-Ping Huang ◽  
Chun-Jung Lin ◽  
U-Ging Lo ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Signaling Pathways ◽  
Therapeutic Potential ◽  
Treatment Options ◽  
Mapk Signaling ◽  
Downstream Signaling ◽  
Cancer Types ◽  
Induced Apoptosis ◽  
Mapk Signaling Pathways

Radiotherapy is one of the most common treatment options for local or regional advanced prostate cancer (PCa). Importantly, PCa is prone to radioresistance and often develops into malignancies after long-term radiotherapy. Antrocin, a sesquiterpene lactone isolated from Antrodia cinnamomea, possesses pharmacological efficacy against various cancer types; however, its therapeutic potential requires comprehensive exploration, particularly in radioresistant PCa cells. In this study, we emphasized the effects of antrocin on radioresistant PCa cells and addressed the molecular mechanism underlying the radiosensitization induced by antrocin. Our results showed that a combination treatment with antrocin and ionizing radiation (IR) synergistically inhibited cell proliferation and induced apoptosis in radioresistant PCa cells. We further demonstrated that antrocin downregulated PI3K/AKT and MAPK signaling pathways as well as suppressed type 1 insulin-like growth factor 1 receptor (IGF-1R)-mediated induction of β-catenin to regulate cell cycle and apoptosis. Using xenograft mouse models, we showed that antrocin effectively enhanced radiotherapy in PCa. Our study demonstrates that antrocin sensitizes PCa to radiation through constitutive suppression of IGF-1R downstream signaling, revealing that it can be developed as a potent therapeutic agent to overcome radioresistant PCa.

scholarly journals Btk Is Required for an Efficient Response to Erythropoietin and for SCF-controlled Protection against TRAIL in Erythroid Progenitors

2004 ◽  
Vol 199 (6) ◽  
pp. 785-795 ◽  
Author(s):  
Uwe Schmidt ◽  
Emile van den Akker ◽  
Martine Parren-van Amelsvoort ◽  
Gabi Litos ◽  
Marella de Bruijn ◽  
...  
Keyword(s):  
Stem Cell ◽  
Signaling Pathways ◽  
Peripheral Blood ◽  
Stem Cell Factor ◽  
Trail Receptor ◽  
Erythroid Progenitors ◽  
Cell Numbers ◽  
Downstream Signaling ◽  
Increased Sensitivity ◽  
Induced Apoptosis

Regulation of survival, expansion, and differentiation of erythroid progenitors requires the well-controlled activity of signaling pathways induced by erythropoietin (Epo) and stem cell factor (SCF). In addition to qualitative regulation of signaling pathways, quantitative control may be essential to control appropriate cell numbers in peripheral blood. We demonstrate that Bruton's tyrosine kinase (Btk) is able to associate with the Epo receptor (EpoR) and Jak2, and is a substrate of Jak2. Deficiency of Btk results in reduced and delayed phosphorylation of the EpoR, Jak2, and downstream signaling molecules such as Stat5 and PLCγ1 as well as in decreased responsiveness to Epo. As a result, expansion of erythroid progenitors lacking Btk is impaired at limiting concentrations of Epo and SCF. In addition, we show that SCF induces Btk to interact with TNF-related apoptosis-inducing ligand (TRAIL)–receptor 1 and that lack of Btk results in increased sensitivity to TRAIL-induced apoptosis. Together, our results indicate that Btk is a novel, quantitative regulator of Epo/SCF-dependent expansion and survival in erythropoiesis.

The effects of Cyclosporin-A (CYA) on the Ultrastructure of Gingival Mast Cells (GMC) in Behcet's disease (BD)

1990 ◽  
Vol 48 (3) ◽  
pp. 358-359
Author(s):  
Oktay Arda ◽  
Ulkü Noyan ◽  
Selgçk Yilmaz ◽  
Mustafa Taşyürekli ◽  
İsmail Seçkin ◽  
...  
Keyword(s):  
Unknown Etiology ◽  
Control Group ◽  
Target Cells ◽  
Gingival Hyperplasia ◽  
Cellular Activity ◽  
Direct Relation ◽  
Immune Disease ◽  
Genital Ulceration ◽  
Functional Changes ◽  
The Third

Turkish dermatologist, H. Beheet described the disease as recurrent triad of iritis, oral aphthous lesions and genital ulceration. Auto immune disease is the recent focus on the unknown etiology which is still being discussed. Among the other immunosupressive drugs, CyA included in it's treatment newly. One of the important side effects of this drug is gingival hyperplasia which has a direct relation with the presence of teeth and periodontal tissue. We are interested in the ultrastructure of immunocompetent target cells that were affected by CyA in BD.Three groups arranged in each having 5 patients with BD. Control group was the first and didn’t have CyA treatment. Patients who had CyA, but didn’t show gingival hyperplasia assembled the second group. The ones displaying gingival hyperplasia following CyA therapy formed the third group. GMC of control group and their granules are shown in FIG. 1,2,3. GMC of the second group presented initiation of supplementary cellular activity and possible maturing functional changes with the signs of increased number of mitochondria and accumulation of numerous dense cored granules next to few normal ones, FIG. 4,5,6.

RELATION OF THE MARKERS OF MYOCARDIAL DYSFUNCTION AND SYSTEMIC INFLAMMATION WITH STRUCTURAL AND FUNCTIONAL PARAMETERS OF THE LUNGS IN MYOCARDIAL INFARCTION PATIENTS

2018 ◽  
Vol 17 (2) ◽  
pp. 24-28
Author(s):  
O. M. Polikutina ◽  
Y. S. Slepynina ◽  
E. D. Bazdyrev ◽  
V. N. Karetnikova ◽  
O. L. Barbarach
Keyword(s):  
Myocardial Infarction ◽  
Systemic Inflammation ◽  
Myocardial Dysfunction ◽  
Control Group ◽  
Chronic Obstructive ◽  
Lung Pathology ◽  
Functional Changes ◽  
Functional Parameters ◽  
Lung Capacity ◽  
Copd Patients

Aim. To evaluate the structural and functional changes in the lungs of ST elevation myocardial infarction (STEMI) patients with absence or presence of chronic obstructive lung disease (COPD), and the relation with myocardial dysfunction and systemic inflammation.Material and methods. Totally, 189 STEMI patients included: group 1 — STEMI with COPD of moderate and mild grade, 2 — STEMI with no lung pathology. Groups were comparable by clinical and anamnestic parameters. Assessment of lung function and blood collection were done at 10­12 day of STEMI. For comparison of the parameters representing structural and functional changes in the lungs and comparison of C­reactive protein (CRP), N­terminal pro­brain natriuretic peptide (NT­proBNP) concentration, a control group was formed with no pulmonary pathology, comparable by age and sex with the STEMI patients.Results. In COPD patients, higher values revealed of the parameters representing the part of residual volumes in pulmonary structure. Higher residual volume (RV) was found also in STEMI and no COPD comparing to controls, however the relation RV/TLC (total lung capacity) was not higher than normal range. In both groups there were lower values of diffusion lung capacity (DLCO) comparing to controls. The lowest DLCO found in COPD patients. Concentration of NT­proBNP (H=41,6; p<0,001) and CRP (H=38,6; p<0,001) in COPD was significantly higher in STEMI with no COPD patients than in controls. The negative correlations found for NT­proBNP and CRP with forced expiratory volume 1 sec, FEV/FVC1, DLCO, and positive — with the values of thoracic volume, RV/TLC.Conclusion. In STEMI patients the increase revealed of residual lung volumes. Mostly the level of residual volumes is high in STEMI and COPD patients. There are associations of NT­proBNP and CRP with structural and functional parameters of the lungs regardless of COPD.

THE DYNACTOME: INVESTIGATING DYNAMIC KINASE NETWORKS IN CELLULAR DECISION-MAKING

2008 ◽  
Vol 31 (4) ◽  
pp. 22
Author(s):  
Jonathan So ◽  
Kelly Elder ◽  
Anna Dai ◽  
Claus Jorgensen ◽  
Rune Linding ◽  
...  
Keyword(s):  
Spectrometric Analysis ◽  
Phosphorylation Sites ◽  
Complex Samples ◽  
Downstream Signaling ◽  
Through Flow ◽  
Colorectal Cancer Cells ◽  
Induced Apoptosis ◽  
Cell Phenotypes ◽  
Kinase Phosphorylation ◽  
Kinase Expression

Networks of kinases play a role in the transmission and integration of signals from the membrane to the nucleus. We aim to elucidate kinase phosphorylation and interaction partners in these networks through the immuno-precipitation and mass spectrometric analysis of a representative set of 100 Flag-tagged kinases stably expressed in human colorectal cancer cells. The goal is to generate a comprehensive set of interactions and dynamic phosphorylation sites which correlate with cell phenotypes such as apoptosis and proliferation. The techniques of mass-spectrometry have allowed for the identification of proteins and their phosphorylation sites in complex samples. Various labeling methods such as iTRAQ has enabled the relative quantification of these sites as afunction of time (White et al. PNAS, 2007). However, kinases usually work in the context of particular signaling stimuli. We aim to characterize the role of these over-expressed kinases in the context of Trail-induced apoptosis. This isparticularly relevant to tumorigenesis in that many cancers are resistant to apoptosis and recombinant Trail therapies are currently undergoing clinical trials. We present assays to correlate the proliferative ability and sensitivity to apoptosis of various stable cell lines with kinase expression levels through flow cytometry. We also present efforts to trace downstream signaling through the monitoring of MAP kinase phosphorylation using a high-throughput bead array.

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