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Mulkey DK, Olsen ML, Ou M, Cleary CM, Du G. Putative Roles of Astrocytes in General Anesthesia. Curr Neuropharmacol 2022; 20:5-15. [PMID: 33588730 PMCID: PMC9199541 DOI: 10.2174/1570159x19666210215120755] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 01/29/2021] [Accepted: 02/06/2021] [Indexed: 02/08/2023] Open
Abstract
General anesthetics are a mainstay of modern medicine, and although much progress has been made towards identifying molecular targets of anesthetics and neural networks contributing to endpoints of general anesthesia, our understanding of how anesthetics work remains unclear. Reducing this knowledge gap is of fundamental importance to prevent unwanted and life-threatening side-effects associated with general anesthesia. General anesthetics are chemically diverse, yet they all have similar behavioral endpoints, and so for decades, research has sought to identify a single underlying mechanism to explain how anesthetics work. However, this effort has given way to the 'multiple target hypothesis' as it has become clear that anesthetics target many cellular proteins, including GABAA receptors, glutamate receptors, voltage-independent K+ channels, and voltagedependent K+, Ca2+ and Na+ channels, to name a few. Yet, despite evidence that astrocytes are capable of modulating multiple aspects of neural function and express many anesthetic target proteins, they have been largely ignored as potential targets of anesthesia. The purpose of this brief review is to highlight the effects of anesthetic on astrocyte processes and identify potential roles of astrocytes in behavioral endpoints of anesthesia (hypnosis, amnesia, analgesia, and immobilization).
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Affiliation(s)
- Daniel K. Mulkey
- Department of Physiology and Neurobiology, University of Connecticut, StorrsCT, USA;,Address correspondence to this author at the Department of Physiology and Neurobiology, University of Connecticut, Storrs CT, USA; E-mail:
| | | | | | - Colin M. Cleary
- Department of Physiology and Neurobiology, University of Connecticut, StorrsCT, USA
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Han XC, Zhang YJ, Dong X, Xing QZ, Li KH, Zhang L. Sevoflurane modulates the cancer stem cell-like properties and mitochondrial membrane potential of glioma via Ca 2+-dependent CaMKII/JNK cascade. Life Sci 2020; 253:117675. [PMID: 32360621 DOI: 10.1016/j.lfs.2020.117675] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 04/01/2020] [Accepted: 04/11/2020] [Indexed: 12/24/2022]
Abstract
AIMS Gliomas are responsible for the majority of deaths from primary brain tumours. Sevoflurane showed inhibition effects on the tumor progression in vitro. However, whether sevoflurane could affect the stemness of glioma stem cells (GSCs) and the potential molecular mechanism have not been well elucidated. MAIN METHODS Effects of sevoflurane on cell viability, proliferation and invasion ability of glioma cells as well as tumor growth in vivo were assessed. Sphere formation assay was performed to evaluate the effect of sevoflurane on the stemness of GSCs. Effects of sevoflurane on mitochondrial function was evaluated by intracellular/mitochondrial reactive oxygen species (ROS) level and mitochondrial membrane potential. Expression levels of proliferation-related proteins, stemness markers and proteins in CaMKII/JNK cascade were measured by Western blot. KEY FINDINGS Sevoflurane inhibited the viability, proliferation and invasion ability of glioma cells (U87MG and U373MG). Western blot showed that sevoflurane decreased the expression levels of proliferation and invasion-related proteins. Sphere formation ability of GSCs, expression levels of stemness markers and mitochondrial function were significantly suppressed by sevoflurane. Moreover, sevoflurane treatment significantly increased the Ca2+ concentration and stimulated phosphorylation of CaMKII, JNK and IRS1. Ca2+ chelator BAPTA-AM combined with sevoflurane synergistically inhibited colony forming ability and the expression levels of proliferation-related proteins and stemness markers. In addition, the in vivo study further confirmed that sevoflurane inhibited tumor growth via Ca2+-dependent CaMKII/JNK cascade. SIGNIFICANCE The present study demonstrated that sevoflurane inhibited glioma tumorigenesis and modulated the cancer stem cell-like properties and mitochondrial membrane potential via activation of Ca2+-dependent CaMKII/JNK cascade.
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Affiliation(s)
- Xue-Chang Han
- The First Affiliated Hospital, and College of Clinical Medicine of Henan University of Science and Technology, No. 24 JingHua Road, Jianxi District, Luoyang 471003, Henan Province, China.
| | - Ya-Jie Zhang
- The First Affiliated Hospital, and College of Clinical Medicine of Henan University of Science and Technology, No. 24 JingHua Road, Jianxi District, Luoyang 471003, Henan Province, China
| | - Xu Dong
- The First Affiliated Hospital, and College of Clinical Medicine of Henan University of Science and Technology, No. 24 JingHua Road, Jianxi District, Luoyang 471003, Henan Province, China
| | - Qun-Zhi Xing
- The First Affiliated Hospital, and College of Clinical Medicine of Henan University of Science and Technology, No. 24 JingHua Road, Jianxi District, Luoyang 471003, Henan Province, China
| | - Ke-Han Li
- The First Affiliated Hospital, and College of Clinical Medicine of Henan University of Science and Technology, No. 24 JingHua Road, Jianxi District, Luoyang 471003, Henan Province, China
| | - Lu Zhang
- The First Affiliated Hospital, and College of Clinical Medicine of Henan University of Science and Technology, No. 24 JingHua Road, Jianxi District, Luoyang 471003, Henan Province, China
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Abstract
BACKGROUND Early postnatal exposure to general anesthetic agents causes a lasting impairment in learning and memory in animal models. One hypothesis to explain this finding is that exposure to anesthetic agents during critical points in neural development disrupts the formation of brain circuitry. Here, we explore the effects of sevoflurane on the neuronal growth cone, a specialization at the growing end of axons and dendrites that is responsible for the targeted growth that underlies connectivity between neurons. METHODS Dissociated neuronal cultures were prepared from embryonic mouse neocortex. Time-lapse images of live growth cones exposed to anesthetics were taken using differential interference contrast microscopy, and the rate of change of the area of the lamellipodia and the speed of the filopodial tip were quantified as measures of motility. The involvement of the p75 neurotropin receptor (p75NTR) was tested using inhibitors applied to the media and by a coimmunoprecipitation assay. RESULTS The rate of lamellipodial area change and filopodial tip velocity in both axonal and dendritic growth cones was significantly reduced with sevoflurane exposure between 2% and 6%. Motility could be substantially restored by treatment with Y27632 and TAT-peptide 5, which are inhibitors of Rho Kinase and p75NTR, respectively. Sevoflurane results in reduced coimmunoprecipitation of Rho-Guanosine-5'-diphosphate dissociation inhibitor after pulldown with p75NTR. CONCLUSIONS Sevoflurane interferes with growth cone motility, which is a critical process in brain circuitry formation. Our data suggest that this may occur through an action on the p75NTR, which promotes growth inhibitory signaling by the Rho pathway.
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Zou W, Ma X, Hua W, Chen B, Huang Y, Wang D, Cai G. BRIP1 inhibits the tumorigenic properties of cervical cancer by regulating RhoA GTPase activity. Oncol Lett 2015; 11:551-558. [PMID: 26870246 PMCID: PMC4727061 DOI: 10.3892/ol.2015.3963] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 10/28/2015] [Indexed: 02/06/2023] Open
Abstract
Breast cancer 1, early onset (BRCA1)-interacting protein 1 (BRIP1), a DNA-dependent adenosine triphosphatase and DNA helicase, is required for BRCA-associated DNA damage repair functions, and may be associated with the tumorigenesis and aggressiveness of various cancers. The present study investigated the expression of BRIP1 in normal cervix tissues and cervical carcinoma via reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry assays. BRIP1 expression was observed to be reduced in squamous cancer tissue and adenocarcinoma compared with normal cervix tissue, and there were significant correlations between the reduction in BRIP1 expression and unfavorable variables, including the International Federation of Gynecologists and Obstetricians stage and presence of lymph node metastases. In order to elucidate the role of BRIP1 in cervical cancer, a BRIP1 recombinant plasmid was constructed and overexpressed in a cervical cancer cell line (HeLa). The ectopic expression of BRIP1 markedly inhibited the tumorigenic properties of HeLa cells in vitro, as demonstrated by decreased cell growth, invasion and adhesion, and increased cell apoptosis. In addition, it was identified that the inhibitory tumorigenic properties of BRIP1 may be partly attributed to the attenuation of RhoA GTPase activity. The present study provides a novel insight into the essential role of BRIP1 in cervical cancer, and suggests that BRIP1 may be a useful therapeutic target for the treatment of this common malignancy.
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Affiliation(s)
- Wei Zou
- Department of Obstetrics and Gynecology, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Xiangdong Ma
- Department of Obstetrics and Gynecology, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Wei Hua
- Department of Obstetrics and Gynecology, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Biliang Chen
- Department of Obstetrics and Gynecology, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Yanhong Huang
- Department of Obstetrics and Gynecology, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Detang Wang
- Department of Obstetrics and Gynecology, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Guoqing Cai
- Department of Obstetrics and Gynecology, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
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Park JH, Shin YJ, Riew TR, Lee MY. The indolinone MAZ51 induces cell rounding and G2/M cell cycle arrest in glioma cells without the inhibition of VEGFR-3 phosphorylation: involvement of the RhoA and Akt/GSK3β signaling pathways. PLoS One 2014; 9:e109055. [PMID: 25268128 PMCID: PMC4182637 DOI: 10.1371/journal.pone.0109055] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2014] [Accepted: 09/02/2014] [Indexed: 12/20/2022] Open
Abstract
MAZ51 is an indolinone-based molecule originally synthesized as a selective inhibitor of vascular endothelial growth factor receptor (VEGFR)-3 tyrosine kinase. This study shows that exposure of two glioma cell lines, rat C6 and human U251MG, to MAZ51 caused dramatic shape changes, including the retraction of cellular protrusions and cell rounding. These changes were caused by the clustering and aggregation of actin filaments and microtubules. MAZ51 also induced G2/M phase cell cycle arrest. This led to an inhibition of cellular proliferation, without triggering significant cell death. These alterations induced by MAZ51 occurred with similar dose- and time-dependent patterns. Treatment of glioma cells with MAZ51 resulted in increased levels of phosphorylated GSK3β through the activation of Akt, as well as increased levels of active RhoA. Interestingly, MAZ51 did not affect the morphology and cell cycle patterns of rat primary cortical astrocytes, suggesting it selectively targeted transformed cells. Immunoprecipitation–western blot analyses indicated that MAZ51 did not decrease, but rather increased, tyrosine phosphorylation of VEGFR-3. To confirm this unanticipated result, several additional experiments were conducted. Enhancing VEGFR-3 phosphorylation by treatment of glioma cells with VEGF-C affected neither cytoskeleton arrangements nor cell cycle patterns. In addition, the knockdown of VEGFR-3 in glioma cells did not cause morphological or cytoskeletal alterations. Furthermore, treatment of VEGFR-3-silenced cells with MAZ51 caused the same alterations of cell shape and cytoskeletal arrangements as that observed in control cells. These data indicate that MAZ51 causes cytoskeletal alterations and G2/M cell cycle arrest in glioma cells. These effects are mediated through phosphorylation of Akt/GSK3β and activation of RhoA. The anti-proliferative activity of MAZ51 does not require the inhibition of VEGFR-3 phosphorylation, suggesting that it is a potential candidate for further clinical investigation for treatment of gliomas, although the precise mechanism(s) underlying its effects remain to be determined.
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Affiliation(s)
- Joo-Hee Park
- Department of Anatomy, Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Yoo-Jin Shin
- Department of Anatomy, Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Tae-Ryong Riew
- Department of Anatomy, Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Mun-Yong Lee
- Department of Anatomy, Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, Seoul, Korea
- * E-mail:
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Kim M, Ham A, Kim KYM, Brown KM, Lee HT. The volatile anesthetic isoflurane increases endothelial adenosine generation via microparticle ecto-5'-nucleotidase (CD73) release. PLoS One 2014; 9:e99950. [PMID: 24945528 PMCID: PMC4063779 DOI: 10.1371/journal.pone.0099950] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Accepted: 02/18/2014] [Indexed: 11/26/2022] Open
Abstract
Endothelial dysfunction is common in acute and chronic organ injury. Isoflurane is a widely used halogenated volatile anesthetic during the perioperative period and protects against endothelial cell death and inflammation. In this study, we tested whether isoflurane induces endothelial ecto-5′-nucleotidase (CD73) and cytoprotective adenosine generation to protect against endothelial cell injury. Clinically relevant concentrations of isoflurane induced CD73 activity and increased adenosine generation in cultured human umbilical vein or mouse glomerular endothelial cells. Surprisingly, isoflurane-mediated induction of endothelial CD73 activity occurred within 1 hr and without synthesizing new CD73. We determined that isoflurane rapidly increased CD73 containing endothelial microparticles into the cell culture media. Indeed, microparticles isolated from isoflurane-treated endothelial cells had significantly higher CD73 activity as well as increased CD73 protein. In vivo, plasma from mice anesthetized with isoflurane had significantly higher endothelial cell-derived CD144+ CD73+ microparticles and had increased microparticle CD73 activity compared to plasma from pentobarbital-anesthetized mice. Supporting a critical role of CD73 in isoflurane-mediated endothelial protection, a selective CD73 inhibitor (APCP) prevented isoflurane-induced protection against human endothelial cell inflammation and apoptosis. In addition, isoflurane activated endothelial cells Rho kinase evidenced by myosin phosphatase target subunit-1 and myosin light chain phosphorylation. Furthermore, isoflurane-induced release of CD73 containing microparticles was significantly attenuated by a selective Rho kinase inhibitor (Y27632). Taken together, we conclude that the volatile anesthetic isoflurane causes Rho kinase-mediated release of endothelial microparticles containing preformed CD73 and increase adenosine generation to protect against endothelial apoptosis and inflammation.
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Affiliation(s)
- Mihwa Kim
- Department of Anesthesiology, College of Physicians and Surgeons of Columbia University, New York, New York, United States of America
| | - Ahrom Ham
- Department of Anesthesiology, College of Physicians and Surgeons of Columbia University, New York, New York, United States of America
| | - Katelyn Yu-Mi Kim
- Department of Anesthesiology, College of Physicians and Surgeons of Columbia University, New York, New York, United States of America
| | - Kevin M. Brown
- Department of Anesthesiology, College of Physicians and Surgeons of Columbia University, New York, New York, United States of America
| | - H. Thomas Lee
- Department of Anesthesiology, College of Physicians and Surgeons of Columbia University, New York, New York, United States of America
- * E-mail:
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Culley DJ, Cotran EK, Karlsson E, Palanisamy A, Boyd JD, Xie Z, Crosby G. Isoflurane affects the cytoskeleton but not survival, proliferation, or synaptogenic properties of rat astrocytes in vitro. Br J Anaesth 2013; 110 Suppl 1:i19-28. [PMID: 23722058 DOI: 10.1093/bja/aet169] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND More than half of the cells in the brain are glia and yet the impact of general anaesthetics on these cells is largely unexamined. We hypothesized that astroglia, which are strongly implicated in neuronal well-being and synapse formation and function, are vulnerable to adverse effects of isoflurane. METHODS Cultured rat astrocytes were treated with 1.4% isoflurane in air or air alone for 4 h. Viability, proliferation, and cytoskeleton were assessed by colorimetric assay, immunocytochemistry, or a migration assay at the end of treatment or 2 days later. Also, primary rat cortical neurones were treated for 4 days with conditioned medium from control [astrocyte-conditioned media (ACM)], or isoflurane-exposed astrocytes (Iso-ACM) and synaptic puncta were assessed by synapsin 1 and PSD-95 immunostaining. RESULTS By several measures, isoflurane did not kill astrocytes. Nor, based on incorporation of a thymidine analogue, did it inhibit proliferation. Isoflurane had no effect on F-actin but reduced expression of α-tubulin and glial fibrillary acidic protein both during exposure (P<0.05 and P<0.001, respectively) and 2 days later (P<0.01), but did not impair astrocyte motility. ACM increased formation of PSD-95 but not synapsin 1 positive puncta in neuronal cultures, and Iso-ACM was equally effective. CONCLUSIONS Isoflurane decreased expression of microtubule and intermediate filament proteins in astrocytes in vitro, but did not affect their viability, proliferation, motility, and ability to support synapses.
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Affiliation(s)
- D J Culley
- Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
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Anesthetics interfere with axon guidance in developing mouse neocortical neurons in vitro via a γ-aminobutyric acid type A receptor mechanism. Anesthesiology 2013; 118:825-33. [PMID: 23364597 DOI: 10.1097/aln.0b013e318287b850] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND The finding that exposure to general anesthetics (GAs) in childhood may increase rates of learning disabilities has raised a concern that anesthetics may interfere with brain development. The generation of neuronal circuits, a complex process in which axons follow guidance cues to dendritic targets, is an unexplored potential target for this type of toxicity. METHODS GA exposures were conducted in developing neocortical neurons in culture and in early postnatal neocortical slices overlaid with fluorescently labeled neurons. Axon targeting, growth cone collapse, and axon branching were measured using quantitative fluorescence microscopy. RESULTS Isoflurane exposure causes errors in Semaphorin-3A-dependent axon targeting (n = 77 axons) and a disruption of the response of axonal growth cones to Semaphorin-3A (n = 2,358 growth cones). This effect occurs at clinically relevant anesthetic doses of numerous GAs with allosteric activity at γ-aminobutyric acid type A receptors, and it was reproduced with a selective agonist. Isoflurane also inhibits growth cone collapse induced by Netrin-1, but does not interfere branch induction by Netrin-1. Insensitivity to guidance cues caused by isoflurane is seen acutely in growth cones in dissociated culture, and errors in axon targeting in brain slice culture occur at the earliest point at which correct targeting is observed in controls. CONCLUSIONS These results demonstrate a generalized inhibitory effect of GAs on repulsive growth cone guidance in the developing neocortex that may occur via a γ-aminobutyric acid type A receptor mechanism. The finding that GAs interfere with axon guidance, and thus potentially with circuit formation, represents a novel form of anesthesia neurotoxicity in brain development.
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Abstract
Numerous studies from the clinical and preclinical literature indicate that general anesthetic agents have toxic effects on the developing brain, but the mechanism of this toxicity is still unknown. Previous studies have focused on the effects of anesthetics on cell survival, dendrite elaboration, and synapse formation, but little attention has been paid to possible effects of anesthetics on the developing axon. Using dissociated mouse cortical neurons in culture, we found that isoflurane delays the acquisition of neuronal polarity by interfering with axon specification. The magnitude of this effect is dependent on isoflurane concentration and exposure time over clinically relevant ranges, and it is neither a precursor to nor the result of neuronal cell death. Propofol also seems to interfere with the acquisition of neuronal polarity, but the mechanism does not require activity at GABAA receptors. Rather, the delay in axon specification likely results from a slowing of the extension of prepolarized neurites. The effect is not unique to isoflurane as propofol also seems to interfere with the acquisition of neuronal polarity. These findings demonstrate that anesthetics may interfere with brain development through effects on axon growth and specification, thus introducing a new potential target in the search for mechanisms of pediatric anesthetic neurotoxicity.
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WIKLUND A, GUSTAVSSON D, EBBERYD A, SUNDMAN E, SCHULTE G, JONSSON FAGERLUND M, ERIKSSON LI. Prolonged attenuation of acetylcholine-induced phosphorylation of extracellular signal-regulated kinase 1/2 following sevoflurane exposure. Acta Anaesthesiol Scand 2012; 56:608-15. [PMID: 22288781 DOI: 10.1111/j.1399-6576.2011.02632.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/30/2011] [Indexed: 01/04/2023]
Abstract
BACKGROUND Volatile anaesthetics are known to affect cholinergic receptors. Perturbation of cholinergic signalling can cause cognitive deficits. In this study, we wanted to evaluate acetylcholine-induced intracellular signalling following sevoflurane exposure. METHODS Pheochromocytoma12 PC12 cells were exposed to 4.6% sevoflurane for 2 h. Subsequently, Western blotting was used to measure acetylcholine-induced phosphorylation of extracellular signal-regulated kinase 1/2 (ERK) 1/2 and basal Protein kinase B (AKT) phosphorylation. RESULTS After exposure, acetylcholine-induced ERK 1/2 phosphorylation was reduced to 58 ± 8% [95% confidence interval (CI): 38-77%, P = 0.003] compared with non-exposed controls. At 30 min after the end of sevoflurane administration [at 0.7% sevoflurane (0.102 mM)], ERK 1/2 phosphorylation remained reduced to 57 ± 7% (95% CI: 39-74%, P = 0.001) and was at 120 min [0.02% (0.003 mM] still reduced to 63 ± 10% (95% CI: 37-88%, P = 0.01), compared with control. At 360 min after exposure, acetylcholine-induced ERK 1/2 phosphorylation had recovered to 98 ± 16% (95% CI: 45-152%, P = 0.98) compared with control. In contrast, immediately after sevoflurane exposure, basal AKT phosphorylation was increased by 228 ± 37% (95% CI: 133-324%, P = 0.02) but had returned to control levels at 30 min after exposure, 172 ± 67% (95% CI: 0-356%, P = 0.34). CONCLUSION Sevoflurane exposure has differential effects on different intracellular signalling pathways. On one hand, we observed a prolonged attenuation of acetylcholine-induced ERK 1/2 phosphorylation that persisted even when sevoflurane concentrations close to detection level. On the other hand, basal AKT phosphorylation was increased twofold during sevoflurane exposure, with a rapid return to baseline levels after exposure. We speculate that the effects on acetylcholine-induced intracellular signalling observed in our in vitro model could be of relevance also for cholinergic signalling in vivo following sevoflurane exposure.
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Affiliation(s)
| | - D. GUSTAVSSON
- Department of Physiology and Pharmacology; Section for Anesthesiology and Intensive Care Medicine; Karolinska Institutet; Stockholm; Sweden
| | - A. EBBERYD
- Department of Physiology and Pharmacology; Section for Anesthesiology and Intensive Care Medicine; Karolinska Institutet; Stockholm; Sweden
| | | | - G. SCHULTE
- Department of Physiology and Pharmacology; Section for Receptor Biology and Signaling; Karolinska Institutet; Stockholm; Sweden
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Ulrich TA, de Juan Pardo EM, Kumar S. The mechanical rigidity of the extracellular matrix regulates the structure, motility, and proliferation of glioma cells. Cancer Res 2009; 69:4167-74. [PMID: 19435897 DOI: 10.1158/0008-5472.can-08-4859] [Citation(s) in RCA: 655] [Impact Index Per Article: 43.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Glioblastoma multiforme (GBM) is a malignant astrocytoma of the central nervous system associated with a median survival time of 15 months, even with aggressive therapy. This rapid progression is due in part to diffuse infiltration of single tumor cells into the brain parenchyma, which is thought to involve aberrant interactions between tumor cells and the extracellular matrix (ECM). Here, we test the hypothesis that mechanical cues from the ECM contribute to key tumor cell properties relevant to invasion. We cultured a series of glioma cell lines (U373-MG, U87-MG, U251-MG, SNB19, C6) on fibronectin-coated polymeric ECM substrates of defined mechanical rigidity and investigated the role of ECM rigidity in regulating tumor cell structure, migration, and proliferation. On highly rigid ECMs, tumor cells spread extensively, form prominent stress fibers and mature focal adhesions, and migrate rapidly. As ECM rigidity is lowered to values comparable with normal brain tissue, tumor cells appear rounded and fail to productively migrate. Remarkably, cell proliferation is also strongly regulated by ECM rigidity, with cells dividing much more rapidly on rigid than on compliant ECMs. Pharmacologic inhibition of nonmuscle myosin II-based contractility blunts this rigidity-sensitivity and rescues cell motility on highly compliant substrates. Collectively, our results provide support for a novel model in which ECM rigidity provides a transformative, microenvironmental cue that acts through actomyosin contractility to regulate the invasive properties of GBM tumor cells.
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Affiliation(s)
- Theresa A Ulrich
- Department of Bioengineering, University of California Berkeley and University of California San Francisco/University of California Berkeley Joint Graduate Group in Bioengineering, Berkeley, CA 94720-1762, USA
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Effects, in an in-vivo model system, of 1,2,3,4-tetrahydroisoquinoline on glioma. Anticancer Drugs 2008; 19:859-70. [DOI: 10.1097/cad.0b013e32830d5887] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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