Sevoflurane inhibits phorbol-myristate-acetate-induced activator protein-1 activation in human T lymphocytes in vitro: potential role of the p38-stress kinase pathway

A comparison of opioid-containing anesthesia versus opioid-free anesthesia using the Cortínez-Sepúlveda model on differential cytokine responses in obese patients undergoing gastric bypass surgery: a randomized controlled trial

Background

Opioid anesthetic agents can modulate the impaired immune response in obese patients through mechanisms that involve the expression and release of cytokines. For this reason, anesthetic care for obese patients remains controversial. Therefore, the aim of the study was to compare the effect of opioid-containing anesthesia (OCA) vs opioid-free anesthesia (OFA) using the Cortínez-Sepúlveda model on IL-6, IL-1β and TNF-α serum levels before and after surgery in obese patients undergoing bypass surgery.

Methods

This randomized cross-sectional study conducted among 40 unrelated obese adults was performed in the Civil Hospital of Guadalajara “Dr. Juan I. Menchaca”. Before undergoing laparoscopic Roux-en-Y gastric bypass, patients were randomly assigned to two anesthesia groups: OCA (n = 20) or OFA (n = 20). Fentanyl was the opioid used in the OCA group. The Cortínez-Sepúlveda pharmacokinetic model was used to characterize the disposition of intravenous propofol for the target-controlled infusion technique in obese patients. Body mass was determined to the nearest 0.05 kg using a balance scale (Seca 703; Seca, Hamburg, Germany). Blood samples were taken before and immediately after surgery and cytokine concentrations were determined by ELISA. Pain was assessed using a numerical pain rating scale. Adverse effects were collected within the first 24 h after surgery.

Results

A total of 6 men and 34 women were included (37.9 ± 10.6 years). Pre-surgery IL-6 and TNF-α serum levels were not detected in study subjects. However, IL-1β levels significantly decreased after surgery (49.58 pg/mL (18.50–112.20)-before surgery vs 13 pg/mL (5.43–22)-after surgery, p = 0.019). IL-6 concentrations were significantly higher in subjects who received OCA (with fentanyl) compared to subjects with OFA (224.5 pg/mL (186.3–262.8) vs 99.5 pg/mL (60.8–138.2), respectively, p < 0.001; adjusted by age, gender, and BMI). In addition, the use of opioids confers an increased risk for higher IL-6 levels in obese patients (OR = 2.95, 95% CI: 1.2–7.2, p = 0.010). A linear regression model showed that the operative time (in hours) of bypass surgery and anesthetic technique were positively correlated with IL-6 levels.

Conclusion

Anesthesia with opioids correlated positively with IL-6 serum levels in obese patients undergoing bypass surgery. This finding could have clinical relevance when an appropriate anesthetic management plan is selected for bariatric surgical patients.

Trial registration

The study was retrospectively registered at ClinicalTrials.gov Identification Number: NCT04854252, date 22/04/2021.

Perioperative Inflammatory Response and Cancer Recurrence in Lung Cancer Surgery: A Narrative Review

While surgical resection is the gold standard treatment for solid tumors, cancer recurrence after surgery is common. Immunosurveillance of remnant tumor cells is an important protective mechanism. Therefore, maintenance of anti-tumor cell activity and proper levels of inflammatory mediators is crucial. An increasing body of evidence suggests that surgery itself and perioperative interventions could affect these pathophysiological responses. Various factors, such as the extent of tissue injury, perioperative medications such as anesthetics and analgesics, and perioperative management including transfusions and methods of mechanical ventilation, modulate the inflammatory response in lung cancer surgery. This narrative review summarizes the pathophysiological mechanisms involved in cancer recurrence after surgery and perioperative management related to cancer recurrence after lung cancer surgery.

The Effects of Anesthetics and Perioperative Medications on Immune Function: A Narrative Review

Preclinical and clinical studies have sought to better understand the effect of anesthetic agents, both volatile and intravenous, and perioperative adjuvant medications on immune function. The immune system has evolved to incorporate both innate and adaptive components, which are delicately interwoven and essential for host defense from pathogens and malignancy. This review summarizes the complex and nuanced relationship that exists between each anesthetic agent or perioperative adjuvant medication studied and innate and adaptive immune function with resultant clinical implications. The most commonly used anesthetic agents were chosen for review including volatile agents (sevoflurane, isoflurane, desflurane, and halothane), intravenous agents (propofol, ketamine, etomidate, and dexmedetomidine), and perioperative adjuvant medications (benzodiazepines, opioids, nonsteroidal anti-inflammatory drugs [NSAIDs], and local anesthetic agents). Patients who undergo surgery experience varying combinations of the aforementioned anesthetic agents and adjuncts, depending on the type of surgery and their comorbidities. Each has unique effects on immunity, which may be more or less ideal depending on the clinical situation. Further study is needed to better understand the clinical effects of these relationships so that patient-specific strategies can be developed to improve surgical outcomes.

Sevoflurane represses the migration and invasion of gastric cancer cells by regulating forkhead box protein 3

Objective

Previous studies suggested that sevoflurane exerts anti-proliferative, anti-migratory, and anti-invasive effects on cancer cells. To determine the role of sevoflurane on gastric cancer (GC) progression, we evaluated its effects on the proliferation, migration, and invasion of SGC7901, AGS, and MGC803 GC cells.

Methods

GC cells were exposed to different concentrations of sevoflurane (1.7, 3.4, or 5.1% v/v). Cell viability, migration, and invasion were evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Transwell assays. Immunohistochemical staining and immunoblotting were performed to analyze forkhead box protein 3 (FOXP3) protein expression in tissue specimens and cell lines, respectively.

Results

FOXP3 was downregulated in human GC specimens and cell lines. Functionally, FOXP3 overexpression significantly inhibited the proliferation, migration, and invasion of GC cells and accelerated their apoptosis. Moreover, sevoflurane significantly blocked GC cell migration and invasion compared with the findings in the control group. However, FOXP3 silencing neutralized sevoflurane-induced apoptosis and the inhibition of GC cell migration and invasion. Sevoflurane-induced apoptosis and the suppression of migration and invasion might be associated with FOXP3 overactivation in GC cells.

Conclusions

Sevoflurane activated FOXP3 and prevented GC progression via inhibiting cell migration and invasion in vitro.

Survival after primary breast cancer surgery following propofol or sevoflurane general anesthesia-A retrospective, multicenter, database analysis of 6305 Swedish patients

BACKGROUND

Retrospective studies indicate that the choice of anesthetic can affect long-term cancer survival. Propofol seems to have an advantage over sevoflurane. However, this is questioned for breast cancer. We gathered a large cohort of breast cancer surgery patients from seven Swedish hospitals and hypothesized that general anesthesia with propofol would be superior to sevoflurane anesthesia regarding long-term breast cancer survival.

METHODS

We identified all patients who were anaesthetized for breast cancer surgery between 2006 and 2012. The patients were matched to the Swedish Breast Cancer Quality Register, to retrieve tumor characteristics, prognostic factors, and adjuvant treatment as well as date of death. Overall survival between patients undergoing sevoflurane and propofol anesthesia was analyzed with different statistical approaches: (a) multiple Cox regression models adjusted for demographic, oncological, and multiple control variables, (b) propensity score matching on the same variables, but also including the participating centers as a cofactor in a separate analysis.

RESULTS

The database analysis identified 6305 patients. The 5-year survival rates were 91.0% and 81.8% for the propofol and sevoflurane group, respectively, in the final model (P = .126). Depending on the statistical adjustment method used, different results were obtained, from a non-significant to a "proposed" and even a "determined" difference in survival that favored propofol, with a maximum of 9.2 percentage points higher survival rate at 5 years (hazard ratio 1.46, 95% CI 1.10-1.95).

CONCLUSIONS

It seems that propofol may have a survival advantage compared with sevoflurane among breast cancer patients, but the inherent weaknesses of retrospective analyses were made apparent.

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.

Multiple sevoflurane exposures don't disturb the T-cell receptor repertoire in infant rhesus monkeys' thymus

AIMS

Multiple surgical procedures and anesthesia increase the risk of the development in children. However, the influence of such exposures on the developing childhood immunity organs is rarely reported.

MATERIALS AND METHODS

High-throughput sequencing of T-cell receptor (TCR) repertoires (TCRseq) from rhesus monkeys' thymus was performed to investigate whether anesthetics could induce de novo antigen recognition via TCR or TCR development impairments.

KEY FINDINGS

No significant difference between sevoflurane and control groups regarding VJ gene combinations and diversity of V and J gene was seen, nor was there an obvious change in similar average number of Complementarity Determining Region 3 (CDR3) aa clonotypes. Our analysis of Rank abundance, Gini coefficient, Simpson index, Normalized Shannon Diversity Entropy (NSDE), Morisita-Horn Similarity Index (MHSI) and Bhattacharyya Distance (BD) indicated there is no difference in TCR diversity and similarity.

SIGNIFICANCE

These results suggest early events in thymic T cell development and repertoire generation are not abnormality after multiple sevoflurane exposure during childhood. The stabilization of the immune repertoires suggested the safety of sevoflurane in host immune response in children.

Intraoperative immunomodulatory effects of sevoflurane versus total intravenous anesthesia with propofol in bariatric surgery (the OBESITA trial): study protocol for a randomized controlled pilot trial

Background

Obesity is associated with a chronic systemic inflammatory process. Volatile or intravenous anesthetic agents may modulate immune function, and may do so differentially in obesity. However, no study has evaluated whether these potential immunomodulatory effects differ according to type of anesthesia in obese patients undergoing laparoscopic bariatric surgery.

Methods/design

The OBESITA trial is a prospective, nonblinded, single-center, randomized, controlled clinical pilot trial. The trial will include 48 patients with a body mass index ≥ 35 kg/m², scheduled for laparoscopic bariatric surgery using sleeve or a Roux-en-Y gastric bypass technique, who will be allocated 1:1 to undergo general inhalational anesthesia with sevoflurane or total intravenous anesthesia (TIVA) with propofol. The primary endpoint is the difference in plasma interleukin (IL)-6 levels when comparing the two anesthetic agents. Blood samples will be collected prior to anesthesia induction (baseline), immediately after anesthetic induction, and before endotracheal extubation. Levels of other proinflammatory and anti-inflammatory cytokines, neutrophil chemotaxis, macrophage differentiation, phagocytosis, and occurrence of intraoperative and postoperative complications will also be evaluated.

Discussion

To our knowledge, this is the first randomized clinical trial designed to compare the effects of two different anesthetics on immunomodulation in obese patients undergoing laparoscopic bariatric surgery. Our hypothesis is that anesthesia with sevoflurane will result in a weaker proinflammatory response compared to anesthesia with propofol, with lower circulating levels of IL-6 and other proinflammatory mediators, and increased macrophage differentiation into the M2 phenotype in adipose tissue.

Trial registration

Registro Brasileiro de Ensaios Clínicos, RBR-77kfj5. Registered on 25 July 2018.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3399-z) contains supplementary material, which is available to authorized users.

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.

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.

Immune Modulation by Volatile Anesthetics

Volatile general anesthetics continue to be an important part of clinical anesthesia worldwide. The impact of volatile anesthetics on the immune system has been investigated at both mechanistic and clinical levels, but previous studies have returned conflicting findings due to varied protocols, experimental environments, and subject species. While many of these studies have focused on the immunosuppressive effects of volatile anesthetics, compelling evidence also exists for immunoactivation. Depending on the clinical conditions, immunosuppression and activation due to volatile anesthetics can be either detrimental or beneficial. This review provides a balanced perspective on the anesthetic modulation of innate and adaptive immune responses as well as indirect effectors of immunity. Potential mechanisms of immunomodulation by volatile anesthetics are also discussed. A clearer understanding of these issues will pave the way for clinical guidelines that better account for the impact of volatile anesthetics on the immune system, with the ultimate goal of improving perioperative management.

Sevoflurane and thiopental preconditioning attenuates the migration and activity of MMP-2 in U87MG glioma cells

BACKGROUND

Tumor cell migration and diffuse infiltration into brain parenchyma are known causes of recurrence after treatment in glioblastoma (GBM), mediated in part by the interaction of glioma cells with the extracellular matrix, followed by degradation of matrix by tumor cell derived proteases, particularly the matrix metalloproteinases (MMP). Sevoflurane and thiopental are anesthetics commonly used in cancer surgery. However, their effect on the progression of glioma cells remains unclear. The aim of this study was to explore the role of these anesthetics on the migration and activity of MMP-2 in glioma cells.

METHODOLOGY

Cultured U87MG cells were pretreated with sevoflurane or thiopental and in vitro wound healing scratch assay was carried out to analyze their effect on migration of these cells. Gelatin zymography was carried out to examine the effect of these anesthetics on tumor cell MMP-2 activity using the conditioned media 24 h after pretreatment. Cell viability was analyzed using 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay.

RESULTS

U87MG cells exposed to 2.5% sevoflurane or different concentrations of thiopental significantly decreased migration and activity of MMP-2 compared to control. No effect was seen on the viability of these cells after pretreatment with sevoflurane or thiopental.

CONCLUSION/SIGNIFICANCE

These results suggest that both sevoflurane and thiopental have inhibitory effect on the migration and MMP-2 activity in glioma cells. Thus, it is important that the choice of anesthetics to be used during glioma surgery takes into account their inhibitory properties against the tumor cells.

Ultrasound-Assisted Thoracic Paravertebral Block Reduces Intraoperative Opioid Requirement and Improves Analgesia after Breast Cancer Surgery: A Randomized, Controlled, Single-Center Trial

OBJECTIVES

The contribution of ultrasound-assisted thoracic paravertebral block to postoperative analgesia remains unclear. We compared the effect of a combination of ultrasound assisted-thoracic paravertebral block and propofol general anesthesia with opioid and sevoflurane general anesthesia on volatile anesthetic, propofol and opioid consumption, and postoperative pain in patients having breast cancer surgery.

METHODS

Patients undergoing breast cancer surgery were randomly assigned to ultrasound-assisted paravertebral block with propofol general anesthesia (PPA group, n = 121) or fentanyl with sevoflurane general anesthesia (GA group, n = 126). Volatile anesthetic, propofol and opioid consumption, and postoperative pain intensity were compared between the groups using noninferiority and superiority tests.

RESULTS

Patients in the PPA group required less sevoflurane than those in the GA group (median [interquartile range] of 0 [0, 0] vs. 0.4 [0.3, 0.6] minimum alveolar concentration [MAC]-hours), less intraoperative fentanyl requirements (100 [50, 100] vs. 250 [200, 300]μg,), less intense postoperative pain (median visual analog scale score 2 [1, 3.5] vs. 3 [2, 4.5]), but more propofol (median 529 [424, 672] vs. 100 [100, 130] mg). Noninferiority was detected for all four outcomes; one-tailed superiority tests for each outcome were highly significant at P<0.001 in the expected directions.

CONCLUSIONS

The combination of propofol anesthesia with ultrasound-assisted paravertebral block reduces intraoperative volatile anesthetic and opioid requirements, and results in less post operative pain in patients undergoing breast cancer surgery.

TRIAL REGISTRATION

ClinicalTrial.gov NCT00418457.

Insight into the beneficial immunomodulatory mechanism of the sevoflurane metabolite hexafluoro-2-propanol in a rat model of endotoxaemia

Volatile anaesthetics such as sevoflurane attenuate inflammatory processes, thereby impacting patient outcome significantly. Their inhalative administration is, however, strictly limited to controlled environments such as operating theatres, and thus an intravenously injectable immunomodulatory drug would offer distinct advantages. As protective effects of volatile anaesthetics have been associated with the presence of trifluorinated carbon groups in their basic structure, in this study we investigated the water-soluble sevoflurane metabolite hexafluoro-2-propanol (HFIP) as a potential immunomodulatory drug in a rat model of endotoxic shock. Male Wistar rats were subjected to intravenous lipopolysaccharide (LPS) and thereafter were treated with HFIP. Plasma and tissue inflammatory mediators, neutrophil invasion, tissue damage and haemodynamic stability were the dedicated end-points. In an endotoxin-induced endothelial cell injury model, underlying mechanisms were elucidated using gene expression and gene reporter analyses. HFIP reduced the systemic inflammatory response significantly and decreased endotoxin-induced tissue damage. Additionally, the LPS-provoked drop in blood pressure of animals was resolved by HFIP treatment. Pathway analysis revealed that the observed attenuation of the inflammatory process was associated with reduced nuclear factor kappa B (NF-κΒ) activation and suppression of its dependent transcripts. Taken together, intravenous administration of HFIP exerts promising immunomodulatory effects in endotoxaemic rats. The possibility of intravenous administration would overcome limitations of volatile anaesthetics, and thus HFIP might therefore represent an interesting future drug candidate for states of severe inflammation.

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 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.

Anesthesia in patients with cancer disorders

PURPOSE OF REVIEW

Along with the increasing population of elderly people in developed countries, anesthesiologists have increasing opportunities to anesthetize cancer patients in their routine work. However, no guideline of anesthesia procedures for cancer patients is available even though guidelines of operative procedures have been formulated for different types of cancer. This review provides recent findings related to the optimal choice of anesthetics and adequate anesthesia management for cancer patients.

RECENT FINDINGS

The intrinsic weapon fighting cancer cells is competent immune cells, particularly CD4+ T helper 1-type cells, CD8+ cytotoxic T cells, and natural killer cells. However, surgical inflammation, some anesthetics, and inadvertent anesthesia management suppress these effector cells and induce suppressive immune cells, which render cancer patients susceptible to tumor recurrence and metastasis after surgery.

SUMMARY

Accumulated basic and clinical data suggest that total intravenous anesthesia with propofol, cyclooxygenase antagonists, and regional anesthesia can decrease negative consequences associated with perioperative immunosuppression. Volatile anesthesia, systemic morphine administration, unnecessary blood transfusions, intraoperative hypoxia, hypotension, hypothermia, and hyperglycemia should be avoided.

Isoflurane enhances malignancy of head and neck squamous cell carcinoma cell lines: a preliminary study in vitro

The objective of this study was to explore the influence of isoflurane on the cell proliferation, apoptosis, and invasion of Tca8113 and HSC2 cell lines in vitro. MTT test was used to detect the cell proliferation. It was performed 72h after exposure to isoflurane to make sure that a time for normal cell cycle progression was allowed. The cell apoptosis of Tca8113 and HSC2 cell lines were detected by flow cytometry. We used transwell chamber to detect the cell invasion of Tca8113 and HSC2 cell lines. There was a statistically significant increase of cell proliferation in Tca8113 and HSC2 cell lines after exposure to 2% isoflurane for 3 and 6h. The difference between 3 and 6h group is statistically significant in Tca8113 and HSC2 cell lines. Flow cytometry showed that there was a decrease of cell apoptosis in Tca8113 and HSC2 cell lines after exposure to 2% isoflurane for 3 and 6h. Transwell test showed there was a statistically significant increase of cell invasion in Tca8113 and HSC2 cell lines after exposure to 2% isoflurane for 3 and 6h, and it showed a significant difference between 3h group and 6h group of Tca8113 cell line. Our results demonstrated that isoflurane increased malignancy of head and neck squamous cell carcinoma cell lines in vitro. Isoflurane might enhance tumor development and promote metastasis of tumor cells in HNSCC patients. It is suggested that it might be more suitable to choose total intravenous anesthesia for HNSCC patients.

Anaesthetic technique may affect prognosis for ovarian serous adenocarcinoma: a retrospective analysis

BACKGROUND

Animal studies have shown that regional anaesthesia and analgesia may prevent or attenuate the surgical stress response by preserving immune function and result in better long-term outcome. We have tested the hypothesis that patients with ovarian serous adenocarcinoma who had surgery with epidural anaesthesia and analgesia would have better long-term outcome than those who were given general anaesthesia (GA) and i.v. opioid analgesia.

METHODS

A retrospective review of medical records identified 143 patients with ovarian serous adenocarcinoma who underwent surgery between January 1994 and October 2006 at the Sun Yat-sen University Cancer Center. Data in the analysis included age, anaesthesia-analgesia technique, ASA status, blood loss, transfusion, duration of surgery, status of preoperative cancer antigen 125, tumour size, International Federation of Gynecology and Obstetrics stage, histological grade, lymph node status, residual macroscopic tumour, and chemotherapy. Survival analysis was made with the main outcome measure of death.

RESULTS

The 3- and 5-yr overall survival rates were 78% and 61% in the patient group who received epidural anaesthesia and analgesia (Group E, n=106), and 58% and 49% in the patient group who received GA and i.v. opioid analgesia (Group G, n=37), respectively. After adjusting for the other variables, Group G had a hazard ratio of 1.214 (P=0.043) in a multivariable Cox regression model compared with Group E.

CONCLUSIONS

This retrospective analysis suggests that epidural anaesthesia and analgesia for ovarian serous adenocarcinoma surgery may reduce mortality during the initial years of follow-up.

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.

Anesthetics, immune cells, and immune responses

General anesthesia accompanied by surgical stress is considered to suppress immunity, presumably by directly affecting the immune system or activating the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system. Along with stress such as surgery, blood transfusion, hypothermia, hyperglycemia, and postoperative pain, anesthetics per se are associated with suppressed immunity during perioperative periods because every anesthetic has direct suppressive effects on cellular and neurohumoral immunity through influencing the functions of immunocompetent cells and inflammatory mediator gene expression and secretion. Particularly in cancer patients, immunosuppression attributable to anesthetics, such as the dysfunction of natural killer cells and lymphocytes, may accelerate the growth and metastases of residual malignant cells, thereby worsening prognoses. Alternatively, the anti-inflammatory effects of anesthetics may be beneficial in distinct situations involving ischemia and reperfusion injury or the systemic inflammatory response syndrome (SIRS). Clinical anesthesiologists should select anesthetics and choose anesthetic methods with careful consideration of the clinical situation and the immune status of critically ill patients, in regard to long-term mortality, morbidity, and the optimal prognosis.

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

BACKGROUND

Modulation of the inflammatory stress response by anesthesia may be responsible for an increased susceptibility to infectious complications, such as wound infection or pneumonia. Sevoflurane, a specific inhibitor of activator protein-1, an immediate early transcription factor, induces apoptosis in T-cells. Because p38 can be involved either in pro- or antiapoptotic processes, we examined whether the sevoflurane-induced apoptosis is mediated by p38 activation in Jurkat T-cells.

METHODS

Jurkat T-cells were exposed to different concentrations of sevoflurane, isoflurane, or desflurane in vitro. Phosphorylation of mitogen-activated protein (MAP) kinases, upstream kinases, downstream activating transcription factor 2 ATF-2, and caspase-3 processing were evaluated by Western blot. p38 kinase activity was evaluated after immunoprecipitation and phosphorylation of the substrate ATF-2 using Western blot. Apoptosis was assessed using flow cytometry after staining with green fluorescent protein-annexin V.

RESULTS

While desflurane had no effect, sevoflurane and isoflurane induced p38 phosphorylation with sevoflurane inducing p38 kinase activity. Sevoflurane did not affect the MAP kinases ERK and JNK. Sevoflurane exposure also induced phosphorylation of apoptosis signal-regulating kinase-1 (ASK1), MAP kinase kinases 3 and 6 (MKK3/MKK6), and ATF-2. Pretreatment of cells with the general caspase inhibitor Z-VAD.fmk did not prevent the sevoflurane-induced phosphorylation of p38. Isoflurane- and sevoflurane-mediated caspase-3 processing and apoptosis could not be abolished by pretreatment with the specific p38 inhibitors SB202190 and SB203580.

CONCLUSIONS

Sevoflurane is a specific activator of the apoptosis signal-regulating kinase-1-, MKK3/MKK6-p38 MAP kinase cascade in Jurkat T-cells. Our data suggest that sevoflurane-induced p38 activation is not affected by caspase activation. Furthermore, sevoflurane-induced apoptosis is not dependent on p38 MAP kinase activation.

Anaesthesia for renal transplant surgery

Renal transplantation is the preferred therapeutic option for patients with end-stage renal disease. Survival rates are much higher in patients who receive a transplant. Patients with renal failure have significant concomitant medical conditions, such as cardiovascular disease. This article provides an overview of the important issues to be considered in patients undergoing renal transplant, and discusses the anaesthetic management of these patients.

Gene expression of pulmonary cytokines after sevoflurane or thiopentone anaesthesia in pigs

BACKGROUND

Volatile anaesthetics have diverse inflammatory effects on the lungs. They increase gene expression of some pro-inflammatory cytokines in alveolar macrophages whereas in alveolar type II cells they seem to decrease secretion and gene expression of pro-inflammatory cytokines. We have previously detected increased leukotriene C4, nitrate and nitrite concentrations in bronchoalveolar lavage fluid after sevoflurane anaesthesia. In the current study, we measured gene expression of inflammatory cytokines in the lung tissue and plasma concentrations of cytokines in pigs after thiopentone or sevoflurane anaesthesia.

METHODS

Sixteen pigs were randomly selected to receive either a continuous thiopentone infusion (control group, n = 8) or sevoflurane (n = 8) at 4.0% inspiratory concentration (1.5 MAC) in air for 6 h. Tissue samples were collected at the end of the study for measurement of gene expression of inflammatory cytokines. Blood samples were collected during anaesthesia for measurement of plasma cytokine concentrations.

RESULTS

Compared with thiopentone anaesthesia, lower gene expression of tumour necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) in lung tissue was observed after sevoflurane anaesthesia. Of measured cytokines IL-1beta, TNF-alpha, IL-6, IL-8 and IL-10 only plasma concentrations of IL-6 could be measured during the study without a difference between the groups.

CONCLUSION

Lower gene expression of TNF-alpha and IL-1beta was found in the intact porcine lung tissue after sevoflurane anaesthesia compared with thiopentone anaesthesia. Clinical significance of this finding is unknown.

Effects of different anaesthetic agents on immune cell function in vitro

BACKGROUND AND OBJECTIVE

Anaesthesia may affect the regulatory balance of postoperative immune response. The aim of this study was to investigate the effects of different volatile and non-volatile anaesthetic agents and particularly of clinically used agent combinations on the proliferation capacity and cytokine production of immune cells.

METHODS

Peripheral blood mononuclear cells from healthy donors were PHA-activated in the presence or absence of various concentrations of thiopental, propofol, fentanyl, sufentanil, sevoflurane, nitrous oxide and combinations of these anaesthetics. Cell proliferation was assessed by tritiated thymidine uptake. Interleukin-2 production and release of the soluble IL-2 receptor were determined by enzyme immunoassays and used as measures of lymphocyte activation.

RESULTS

Thiopental inhibited cell proliferation in a dose dependent manner (P < 0.001) and reduced sIL-2R release (2090-970 microg mL(-1); P < 0.05). Propofol reduced sIL-2R release at the high concentration of 10 microg mL(-1) (2220 pg mL(-1) 1780 microg mL(-1); p < 0.05). Fentanyl and sufentanil did not compensate for or enhance the inhibitory effects of thiopental. Nitrous oxide, but not sevoflurane, reduced the proliferation of human peripheral blood mononuclear cells (P < 0.05). In combinations with thiopental or nitrous oxide, sevoflurane compensated the inhibitory effects of these two agents. Fentanyl, sufentanil, sevoflurane and nitrous oxide did not affect PHA-induced IL-2 and sIL-2 receptor release by human peripheral blood mononuclear cells.

CONCLUSION

Thiopental and nitrous oxide have immunosuppressive activity. In contrast, sevoflurane may have a beneficial effect by alleviating the immunosuppressive effects of both substances.