Sevoflurane-mediated activation of p38-mitogen-activated stresskinase is independent of apoptosis in Jurkat T-cells

Sevoflurane Inhibits Metastasis in Hepatocellular Carcinoma by Inhibiting MiR-665-Induced Activation of the ERK/MMP Pathway

Recent evidence has indicated that inhalational anesthetics may affect the growth and malignant potential of tumor cells and ultimately influence tumor recurrence after surgery. Sevoflurane, a volatile anesthetic, is used extensively in hepatectomy. However, the effect of sevoflurane on the growth of hepatocellular carcinoma (HCC) cells remains unknown. The aim of this study was to explore the effects of sevoflurane on HCC metastasis and its potential mechanisms in the human HCC cell lines, HepG2 and SMMC7721. HepG2 and SMMC7721 cells were treated with 1.7%, 3.4%, and 5.1 % sevoflurane for 6 h. Cell migration was analyzed using invasion, migration, and scratch assays. Based on previous literature, several microRNAs (miRNAs) were screened to determine regulatory miRNA targets of sevoflurane in HepG2 and SMMC7721 cells; miR-665 was detected as a potential target and overexpressed or inhibited in HepG2 and SMMC7721 cells by a lentiviral system. The p-ERK/MMP pathway was also measured by western blotting. Sevoflurane inhibited the migration and invasion of HCC cells in a dose-dependent manner. It also inhibited miR-665 expression in HCC cells. We further observed that sevoflurane inhibited HCC metastasis via miR-665. Sevoflurane-induced downregulation of miRNA-665 led to phosphorylation of ERK and matrix metalloproteinase (MMP-9) via suppression of SPRED1. These results demonstrated that sevoflurane may inhibit invasion and migration via the p-ERK/MMP-9 signaling pathway in HCC cells.

Anti-Proliferative Effect of Allium senescens L. Extract in Human T-Cell Acute Lymphocytic Leukemia Cells

Allium species are well known plants distributed throughout the world, and they contain various bioactive components with different biological activities including anti-cancer effects. In this study, we investigated the inhibitory effect of Allium senescens L. (A.S.) extract on cell survival and IL-2-mediated inflammation in human T cell acute lymphocytic leukemia (T-ALL) Jurkat cells. Our results showed that A.S. extract induced caspase-dependent apoptosis of Jurkat cells with no significant cytotoxicity in the normal peripheral blood mononuclear cells. A.S. extract induced ROS generation through the activation of MAPK p38 phosphorylation. It also inhibited IL-2 mRNA expression and NF-κB signaling mediated by phorbol 12-myristate 13-acetate, and phytohemagglutinin. Combined treatment with A.S. extract and axitinib/dovitinib exerted enhanced inhibitory effects on T-ALL cell growth and IL-2 production. These results provide novel information on the potential use of A.S. extract as a therapeutic herbal agent for the treatment and prevention of T-ALL.

Sevoflurane inhibits the proliferation and invasion of hepatocellular carcinoma cells through regulating the PTEN/Akt/GSK‑3β/β‑catenin signaling pathway by downregulating miR‑25‑3p

Sevoflurane (Sevo) is one of the most frequently used volatile anesthetic agents in surgical oncology and has various effects on tumors, including inhibiting tumor growth, recurrence, and metastases; however, the molecular mechanisms are unknown. This study tried to investigate the influence of Sevo on hepatocellular carcinoma (HCC) cells and its possible mechanisms of action. The present study found that Sevo suppressed both the proliferative and invasive capabilities of both HCCLM3 and Huh7 cells in a dose-dependent manner. Moreover, 53 differentially expressed microRNAs (miRNAs/miRs) in HCC cells that resulted from Sevo were screened out using miRNA microarray assay. In particular, miR-25-3p displayed a significant decrease in response to Sevo treatment. Further studies showed that Sevo's inhibitory actions on HCC cells were attenuated by overexpression of miR-25-3p but enhanced by its inhibitor. Phosphatidylinositol 3,4,5-trisphosphate 3-phosphatase and dual-specificity protein phosphatase PTEN (PTEN), a tumor suppressor gene, was directly targeted by miR-25-3p and its expression was upregulated by Sevo. In addition, Sevo suppressed the expression of phosphorylated-protein kinase B (p-Akt) (S473), glycogen synthase kinase (GSK) 3β (p-GSK3β) (S9), β-catenin, c-Myc and matrix metalloproteinase 9; whereas these inhibitory effects were reversed by miR-25-3p overexpression. More importantly, Sevo's tumor-suppressive effects were enhanced by LY294002 (a PI3-kinase inhibitor) but weakened by insulin growth factor-1 (an agonist of the Akt signaling pathway). These data suggest that Sevo's antitumor effects on HCC could be explained, in part, by Sevo inhibiting the miR-25-3p/PTEN/Akt/GSK-3β/β-catenin signaling pathway.

Sevoflurane inhibited inflammatory response induced by TNF-α in human trophoblastic cells through p38MAPK signaling pathway

Purpose: Excessive inflammatory response is one of the possible pathogenic mechanisms of preeclampsia (PE). It remains unclear whether sevoflurane has an anti-inflammatory effect in human trophoblastic cells, which are corresponding to the dysfunction of placentas in PE. This study probed into the regulatory function of sevoflurane toward HTR8/SVneo cells so as to find PE pathology and PE treatment.Materials and methods: HTR8/SVneo cells were treated with sevoflurane, TNF-α with different concentrations, sevoflurane plus 10 ng/mL TNF-α and SB203580 plus 10 ng/mL TNF-α. Cell counting kit-8 (CCK-8) assays were performed to detect cell viability, while enzyme linked immunoSorbent assay (ELISA) was used to measure IL-6, IL-8, GM-CSF and MCP-1 levels in HTR8/SVneo cells. Besides, relative mRNA expression levels of IL-6 and IL-8 were tested via quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR), and p38 phosphorylation-related protein expressions were assessed through western blot.Results: Cell viability remained stable when HTR8/SVneo cells were treated with or without sevoflurane and SB203580 in inflammatory microenvironment created by TNF-α. MCP-1 and GM-CSF levels, as well as gene expressions of IL-6 and IL-8 in HTR8/SVneo cells were greatly increased by TNF-α (5, 10 and 20 ng/mL), but reversed by sevoflurane and SB203580. Simultaneously, TNF-α-induced phosphorylation of p38MAPK signaling pathway was inhibited by sevoflurane and SB203580.Conclusions: Sevoflurane inhibited inflammatory response induced by TNF-α in human trophoblastic cells HTR8/SVneo through suppressing the phosphorylation of p38MAPK signaling pathway.

Clinically relevant concentration of sevoflurane suppresses cervical cancer growth and migration through targeting multiple oncogenic pathways

The biological effects of sevoflurane, a volatile anesthetics, on cancer cells seem to be contradictory and are not fully understood. While some studies demonstrate that sevoflurane promotes tumor growth, other studies report that sevoflurane displays anti-cancer activities. In this work, we systematically investigated the effects of sevoflurane at clinically relevant dose on the multiple biological aspects of cervical cancer cells and analyzed the underlying mechanism. Using a panel of cell lines, we found that sevoflurane significantly inhibited proliferation and migration of cervical cancer cells regardless of cellular origin and genetic background. In contrast, sevoflurane did not affect cervical cancer survival. Additionally, sevoflurane significantly enhanced chemosensitivity of cervical cancer cells. Mechanistically, we show that sevoflurane inhibits Ras and RhoA GTPase activities, leading to the blockade of their downstream signaling pathways, such as Ras/Erk/Akt and Rho/MYPT1/MLC. The rescue studies using Rho activator calpeptin or constitutively active Ras further confirm that Ras and RhoA are the targets of sevoflurane in cervical cancer. Interestingly, we found that the anti-proliferative effect of sevoflurane was via targeting Ras whereas the anti-migratory effect of sevoflurane was mediated via targeting RhoA. Our data clearly demonstrates the anti-cancer effects of sevoflurane. These findings provide preclinical evidence into the potential mechanisms by which sevoflurane may negatively affect cervical cancer growth and metastasis.

Volatile anesthetics sevoflurane targets leukemia stem/progenitor cells via Wnt/β-catenin inhibition

Most of the studies regarding the direct effect of anesthetics on tumour cells are focused on opioids and voltage-gated sodium channels. Little is known on the effect of volatile anesthetics on tumour progression. In this study, we show that sevoflurane, a volatile anesthetic, negatively affects chronic myeloid leukemia (CML) CD34 stem/progenitor cells' biological properties. Sevoflurane significantly inhibits the growth of a panel of CML cell lines in a dose-dependent manner without affecting their survival. It also inhibits proliferation, differentiation and self-renewal capacities but not survival of CML CD34 cells. In addition, sevoflurane significantly augments dasatinib's efficacy in CML cell lines and stem/progenitors. Mechanistically, sevoflurane dose-dependently decreases levels of β-catenin and c-Myc but not phospho-P38 MAPK in K562 and CML CD34 cells. The decreased Wnt/ β-catenin activity and the reduced levels of Wnt/β-catenin-targeted transcriptions are observed in CML cells exposed to sevoflurane. The complete rescue of the inhibitory effects of sevoflurane in K562 and CML CD34 cells by β-catenin stabilization using both genetic and pharmacological approaches further demonstrates that sevoflurane acts on CML cells via a β-catenin-dependent manner. Our results clearly show the direct and negative effects of sevoflurane on the leukemia cell lines as well as leukemia stem/progenitors. Our findings also reveal Wnt/β-catenin as the target of volatile anesthetics.

Collapsin Response Mediator Protein-2 Ameliorates Sevoflurane-Mediated Neurocyte Injury by Targeting PI3K-mTOR-S6K Pathway

Background

Collapsin response mediator protein-2 (CRMP-2) is the first member of the CRMP family that has been identified in primary neuronal cells; it was originally found and identified in the regulation of microtubule dimerization into microtubules.

Material/Methods

In the present study, we aimed to investigate the roles and mechanisms of CRMP-2 in sevoflurane-induced neurocyte injury. Cell viability, proliferation, and apoptosis were measured by Cell Counting Kit-8 (CCK-8) assay and flow cytometry. Colorimetry was performed to measure the activity of caspase-3. Western blot and quantitative real-time reverse transcription assays were used to evaluate the related mRNAs and proteins expression.

Results

We found that CRMP-2 reversed the inhibitory effect of sevoflurane on the viability of nerve cells. Moreover, CRMP-2 accelerated the proliferation and suppressed the apoptosis of sevoflurane-induced nerve cells. CRMP-2 modulated the expression levels of apoptosis-associated protein in sevoflurane-induced nerve cells. Furthermore, it was demonstrated that CRMP-2 impacted the PI3K-mTOR-S6K pathway.

Conclusions

CRMP2 ameliorated sevoflurane-mediated neurocyte injury by targeting the PI3K-mTOR-S6K pathway. Thus, CRMP2 might be an effective target for sevoflurane-induced neurocyte injury therapies.

Prolonged duration of isoflurane anesthesia impairs spatial recognition memory through the activation of JNK1/2 in the hippocampus of mice

Postoperative cognitive dysfunction is a frequent complication with surgery and anesthesia, and the underlying mechanism is unclear. Our aim was to investigate the effect of different durations of isoflurane anesthesia on spatial recognition memory and activation of JNK1/2 in the hippocampus of mice. In the present study, adult male mice were anesthetized with isoflurane for different durations (1.5% isoflurane for 1, 2, and 4 h). Spatial recognition memory was determined using spontaneous alternation and two-trial recognition memory in Y-maze at 24 h after anesthesia. The activation of JNK1/2 in the hippocampus was tested using western blot. Mice treated with isoflurane for 4 h showed significantly decreased spontaneous alternations and decreased exploration parameters compared with the no anesthesia group, but this was not observed in mice treated with isoflurane for 1 or 2 h. The protein levels of p-JNK1/2 in the hippocampus were significantly increased at 10 min after isoflurane anesthesia for 1, 2, and 4 h compared with no anesthesia. However, only isoflurane anesthesia for 4 h still increased JNK1/2 and p-JNK1/2 levels at 24 h after anesthesia. We concluded that prolonged duration of isoflurane anesthesia maintained the activation of JNK1/2, which led to memory impairment at 24 h after anesthesia.

Sevoflurane inhibits the malignant potential of head and neck squamous cell carcinoma via activating the hypoxia‑inducible factor-1α signaling pathway in vitro

Sevoflurane, an inhalational anesthetic, is extensively used during oral cancer surgery. However, the effect of sevoflurane on head and neck squamous cell carcinoma (HNSCC) remains unclear. The objective of the present study was to investigate the effects of sevoflurane on the proliferation, apoptosis and invasion in HNSCC cell lines and the underlying molecular mechanism. The Cell Counting Kit-8 assay was used to evaluate cell proliferation. Apoptosis was analyzed by flow cytometry. Cell invasion was evaluated using the Transwell invasion assay. The expression levels of Akt, p-Akt (Ser473), hypoxia‑inducible factor-1α (HIF-1α), Fas and Bcl-2 were measured by western blotting. Significant inhibition of cell proliferation and induction of apoptosis were observed in FaDu and CAL-27 cells following sevoflurane treatment. The expression of Akt, p-Akt (Ser473) and Bcl-2 was supressed, while that of Fas was significantly increased, which was partly associated with the activation of the HIF-1α pathway. In addition, the results revealed a statistically significant inhibition of cell invasion in the FaDu cell line following exposure to 2 and 4% sevoflurane for 2, 4, 6 and 8 h. Therefore, the present study demonstrated that sevoflurane decreased the malignant behavior of HNSCC cell lines in vitro, which was associated with activation of the HIF-1α pathway.

Sevoflurane decreases self-renewal capacity and causes c-Jun N-terminal kinase-mediated damage of rat fetal neural stem cells

Increasing studies have demonstrated that sevoflurane can induce neurotoxicity in the developing brains. JNK normally promotes apoptosis. It was hypothesized that sevoflurane affected the proliferation and differentiation of FNSCs and induced cell apoptosis, which caused the learning and memory deficits via JNK pathway. Sevoflurane at a concentration of 1.2% did not induce damage on the FNSCS. However, concentrations of 2.4% and 4.8% decreased the cell viability, as shown by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and increased apoptosis, as shown by flow cytometry. The 5-ethynyl-2'-deoxyuridine (EdU) incorporation assay demonstrated that 4.8% sevoflurane reduced the proliferation of FNSCs. Compared with the control group, the 4.8% sevoflurane group showed a decrease in the proportion of undifferentiated FNSCs at 6-h exposure; 4.8% sevoflurane could increase the p-JNK/JNK ratio. JNK inhibition by the specific inhibitor SP600125 enhanced partially the cell viability. Cumulatively, 4.8% sevoflurane induced significant damage on FNSCs; it decreased cell proliferation and proportion of undifferentiated cells as well. JNK pathway might play a key role in the decrease in survival of FNSCs induced by an inhaled anesthetic. The present findings might raise the possibility that JNK inhibition has therapeutic potential in protecting FNSCs from the adverse effects of the inhaled anesthetic.

Sevoflurane inhibits the migration and invasion of glioma cells by upregulating microRNA-637

Cancer cell migration and invasion are essential features of the metastatic process. Volatile anesthetic sevoflurane inhibits the migration and invasion of multiple cancer cell lines; however, its effects on glioma cells are unclear. Emerging evidence suggests that microRNA (miRNA)-637 regulates glioma cell migration and invasion through the Akt1 pathway. Sevoflurane has been shown to modulate a number of miRNAs. In the present study, we examined whether sevoflurane inhibits glioma cell migration and invasion and, if so, whether these beneficial effects are mediated by miRNA-637. U251 glioma cells were treated without (control) or with sevoflurane at low, moderate or high concentrations for 6 h. To explore the molecular mechanisms, an additional group of U251 cells was treated with a miRNA‑637 inhibitor prior to treatment with a high concentration of sevoflurane. Compared with the control group, sevoflurane inhibited the migration and invasion of U251 cells in a dose-dependent manner. Molecular analyses revealed that sevoflurane increased the expression of miRNA‑637 and decreased the expression of Akt1 and phosphorylated Akt1 in a dose-dependent manner. Moreover, the inhibitory effects of sevoflurane on U251 cell migration and invasion were completely abolished by pre-treatment with miRNA‑637 inhibitor, which reversed the sevoflurane-induced reduction in the expression of Akt1 and phosphorylated Akt1 in the U251 cells. These results demonstrate that sevoflurane inhibits glioma cell migration and invasion and that these beneficial effects are mediated by the upregulation of miRNA‑637, which suppresses Akt1 expression and activity. These findings may have significant clinical implications for anesthesiologists regarding the choice of volatile anesthetic agents for the surgical resection of gliomas to prevent metastases and improve patient outcomes.

Dobutamine mediates cytoprotection by induction of heat shock protein 70 in vitro

AIMS

Dobutamine is cytoprotective when applied before a subsequent stress. However, the underlying molecular mechanism is unknown. Dobutamine also inhibits nuclear factor (NF)-κB in human T lymphocytes. Other inhibitors of NF-κB induce a so-called heat shock response. We hypothesized that dobutamine mediates protection from apoptotic cell death by the induction of a heat shock response.

MAIN METHODS

Jurkat T lymphoma cells were preincubated with dobutamine (0.1, 0.5 mM) before the induction of apoptosis (staurosporine, 2 μM). DNA-binding of heat shock factor (HSF)-1 was analyzed by electrophoretic mobility shift assay, mRNA-expression of heat shock protein (hsp)70 and hsp90 by Northern Blot, activity of caspase-3 by fluorogenic caspase activity assay and cleavage of pro-caspase-3 by Western Blot. Apoptosis was assessed by flow cytometry after annexin V-fluorescein isothiocyanate staining. Hsp70 and hsp90 were inhibited using N-formyl-3,4-methylenedioxy-benzylidene-gamma-butyrolaetam and 17-allylamino-17-demethoxygeldana-mycin, respectively. All data are given as median and 25/75% percentile.

KEY FINDINGS

Pre-incubation with dobutamine inhibited staurosporine-induced annexin V-fluorescence (28 [20-32] % vs. 12 [9-15] % for dobutamine 0.1 mM and 7 [5-12] % for dobutamine 0.5 mM, p<0.001), cleavage of pro-caspase-3 as well as caspase-3-like activity (0.46 [0.40-0.48] vs. 0.32 [0.27-0.39] for Dobutamine 0.1 mM and 0.20 [0.19-0.23] for Dobutamine 0.5 mM, p<0.01). Dobutamine induced DNA-binding of HSF-1 and mRNA-expression of hsp70 and hsp90. While inhibition of Hsp90 had no effect, inhibition of Hsp70 increased the number of annexin V-positive cells (33 [32-36] % vs. 18 [16-24] %) and caspase-3-like activity (0.21 [0.19-0.23] vs. 0.16 [0.13-0.17], p<0.05).

SIGNIFICANCE

Dobutamine protects from apoptotic cell death via the induction of Hsp70.

The common anesthetic, sevoflurane, induces apoptosis in A549 lung alveolar epithelial cells

Lung alveolar epithelial cells are the first barrier exposed to volatile anesthetics, such as sevoflurane, prior to reaching the targeted neuronal cells. Previously, the effects of volatile anesthetics on lung surfactant were studied primarily with physicochemical models and there has been little experimental data from cell cultures. Therefore it was investigated whether sevoflurane induces apoptosis of A549 lung epithelial cells. A549 cells were exposed to sevoflurane via a calibrated vaporizer with a 2 l/min flow in a gas‑tight chamber at 37˚C. The concentration of sevoflurane in Dulbecco's modified Eagle's medium was detected with gas chromatography. Untreated cells and cells treated with 2 µM daunorubicin hydrochloride (DRB) were used as negative and positive controls, respectively. Apoptosis factors, including the level of ATP, apoptotic‑bodies by terminal deoxynucleotidyl transferase‑mediated dUTP nick end labeling (TUNEL) assay, DNA damage and the level of caspase 3/7 were analyzed. Cells treated with sevoflurane showed a significant reduction in ATP compared with untreated cells. Effects in the DRB group were greater than in the sevoflurane group. The difference of TUNEL staining between the sevoflurane and untreated groups was statistically significant. DNA degradation was observed in the sevoflurane and DRB groups, however this was not observed in the untreated group. The sevoflurane and DRB groups induced increased caspase 3/7 activation compared with untreated cells. These results suggest that sevoflurane induces apoptosis in A549 cells. In conclusion, 5% sevoflurane induced apoptosis of A549 lung alveolar epithelial cells, which resulted in decreased cell viability, increased apoptotic bodies, impaired DNA integrality and increased levels of caspase 3/7.

Sevoflurane combined with ATP activates caspase-1 and triggers caspase-1-dependent pyroptosis in murine J774 macrophages

Sevoflurane is one of the most commonly used volatile anesthetics. Recent studies have shown that sevoflurane plays an important role in modulation of inflammation and immunity. However, little is known about the related molecular mechanisms. This study was designed to investigate the effects and mechanisms of sevoflurane on inflammatory cell death pyroptosis in the murine macrophage cell line J774 cells. Sevoflurane combined with ATP could increase the level of activated caspase-1, pyroptosis, and reactive oxygen species (ROS). Furthermore, treatment of cells with the caspase-1 inhibitor Ac-YVAD-CMK dramatically decreased the percentage of pyroptosis. In addition, inhibition of ROS with N-acetyl-L-cysteine or diphenyleneiodonium significantly reduced the activated levels of caspase-1. These results demonstrated that sevoflurane combined with ATP could activate caspase-1 and trigger caspase-1-dependent pyroptosis through the modulation of ROS production.

Sevoflurane reduces clinical disease in a mouse model of multiple sclerosis

Background

Inhalational anesthetics have been shown to influence T cell functions both in vitro and in vivo, in many cases inducing T cell death, suggesting that exposure to these drugs could modify the course of an autoimmune disease. We tested the hypothesis that in mice immunized to develop experimental autoimmune encephalomyelitis (EAE), a well established model of multiple sclerosis (MS), treatment with the commonly used inhalational anesthetic sevoflurane would attenuate disease symptoms.

Methods

C57Bl6 female mice were immunized with myelin oligodendrocyte glycoprotein (MOG) peptide residues 35 to 55 to induce a chronic demyelinating disease. At day 10 after immunization, the mice were subjected to 2 h of 2.5% sevoflurane in 100% oxygen, or 100% oxygen, alone. Following treatment, clinical scores were monitored up to 4 weeks, after which brain histology was performed to measure the effects on astrocyte activation and lymphocyte infiltration. Effects of sevoflurane on T cell activation were studied using splenic T cells isolated from MOG peptide-immunized mice, restimulated ex vivo with MOG peptide or with antibodies to CD3 and CD28, and in the presence of different concentrations of sevoflurane. T cell responses were assessed 1 day later by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay for proliferation, lactate dehydrogenase (LDH) release for cell death, and inflammatory activation by production of interleukin (IL)-17 and interferon (IFN)γ.

Results

Clinical scores in the oxygen-treated group increased until day 28 at which time they showed moderate to severe disease (average clinical score of 2.9). In contrast, disease progression in the sevoflurane-treated group increased to 2.1 at day 25, after which it remained unchanged until the end of the study. Immunohistochemical analysis revealed reduced numbers of infiltrating leukocytes and CD4⁺ cells in the CNS of the sevoflurane-treated mice, as well as reduced glial cell activation. In splenic T cells, low doses of sevoflurane reduced IFNγ production, cell proliferation, and increased LDH release.

Conclusions

These results are the first to show attenuation of EAE disease by an inhaled anesthetic and are consistent with previous reports that inhaled anesthetics, including sevoflurane, can suppress T cell activation that, in the context of autoimmune diseases such as MS, could lead to reduced clinical progression.

Attenuating sevoflurane-induced cellular injury of human peripheral lymphocytes by propofol in a concentration-dependent manner

Sevoflurane, one of the most commonly used inhalation anesthetics, induces apoptosis and oxidative stress in lymphocytes. Propofol, an intravenous anesthetic, exhibits antiapoptotic and antioxidative activities. Therefore, the present study aimed to investigate whether propofol attenuates sevoflurane-induced cellular injury in human peripheral lymphocytes. Lymphocytes harvested from healthy volunteers were assigned to treatments with different concentrations of propofol, or 8% sevoflurane, or their combination. Propofol at concentrations of 5, 10 or 25 μg/mL had little effect, but 50 μg/mL propofol or 8% sevoflurane significantly reduced cell viability and mitochondrial membrane potential (ΔΦm), and increased cell apoptosis, activation of caspase-3 and the production of intracellular reactive oxygen species, compared with untreated cells. Five and ten μg/mL propofol attenuated the impact of sevoflurane on cell viability, apoptosis and ΔΦm, and 5, 10 and 25 μg/mL propofol inhibited the production of intracellular reactive oxygen species stimulated by sevoflurane. However, a combination of 50 μg/mL propofol and 8% sevoflurane led to more severe cellular injury than sevoflurane alone. The results suggest that propofol can attenuate sevoflurane-induced cellular injury of human peripheral lymphocytes in a concentration-dependent manner, providing a rational for the clinical use of sevoflurane combined with appropriate doses of propofol.

The common inhalational anesthetic sevoflurane induces apoptosis and increases beta-amyloid protein levels

OBJECTIVE

To assess the effects of sevoflurane, the most commonly used inhalation anesthetic, on apoptosis and beta-amyloid protein (Abeta) levels in vitro and in vivo. Subjects Naive mice, H4 human neuroglioma cells, and H4 human neuroglioma cells stably transfected to express full-length amyloid precursor protein.

INTERVENTIONS

Human H4 neuroglioma cells stably transfected to express full-length amyloid precursor protein were exposed to 4.1% sevoflurane for 6 hours. Mice received 2.5% sevoflurane for 2 hours. Caspase-3 activation, apoptosis, and Abeta levels were assessed.

RESULTS

Sevoflurane induced apoptosis and elevated levels of beta-site amyloid precursor protein-cleaving enzyme and Abeta in vitro and in vivo. The caspase inhibitor Z-VAD decreased the effects of sevoflurane on apoptosis and Abeta. Sevoflurane-induced caspase-3 activation was attenuated by the gamma-secretase inhibitor L-685,458 and was potentiated by Abeta. These results suggest that sevoflurane induces caspase activation which, in turn, enhances beta-site amyloid precursor protein-cleaving enzyme and Abeta levels. Increased Abeta levels then induce further rounds of apoptosis.

CONCLUSIONS

These results suggest that inhalational anesthetic sevoflurane may promote Alzheimer disease neuropathogenesis. If confirmed in human subjects, it may be prudent to caution against the use of sevoflurane as an anesthetic, especially in those suspected of possessing excessive levels of cerebral Abeta.