Anesthetic Propofol Attenuates Apoptosis, Aβ Accumulation, and Inflammation Induced by Sevoflurane Through NF-κB Pathway in Human Neuroglioma Cells

Propofol total intravenous anesthesia vs. sevoflurane inhalation anesthesia: Effects on post‑operative cognitive dysfunction and inflammation in geriatric patients undergoing laparoscopic surgery

Propofol total intravenous anesthesia (TIVA) or sevoflurane inhalation anesthesia (IA) affects post-operative cognitive dysfunction in geriatric patients undergoing laparoscopic surgery; however, relevant real-world clinical evidence on the matter is limited. The present study aimed to compare the effects of propofol TIVA and sevoflurane IA on post-operative cognitive dysfunction in the aforementioned type of patients. The present prospective study enrolled 197 geriatric patients undergoing laparoscopic surgery. Patients were assigned to the propofol TIVA group (n=97) and sevoflurane IA group (n=100) according to the actual anesthesia regimens. The mini-mental state examination (MMSE) score was assessed before surgery and on day (D)1, D3 and D7 following surgery in both groups. The MMSE score on D1 was higher in the TIVA group compared with the IA group (P=0.006). The change in the MMSE scores from before surgery to D1 (P<0.001), D3 (P=0.011) and D7 (P=0.003) was smaller in the TIVA group vs. the IA group. Multivariate linear regression analyses suggested that the anesthesia method of TIVA (vs. IA) was independently related to the increased MMSE score on D1 (b=0.803; P=0.001) and D7 (b=0.472; P=0.025). The levels of interleukin (IL)-17A, IL-6 and tumor necrosis factor-α on D1, D3 and D7 exhibited a slightly decreasing trend in the TIVA group vs. the IA group, although the difference was not statistically significant (all P>0.05). Notably, the levels of IL-17A before surgery (P=0.015), on D3 (P=0.016) and D7 (P=0.002), as well as those of IL-6 on D1 (P=0.027), were negatively associated with the MMSE score at the corresponding time points. Overall, the present study demonstrates that propofol TIVA ameliorates post-operative cognitive dysfunction on D1 compared with sevoflurane IA and exerts a potentially suppressive effect on inflammation in geriatric patients undergoing laparoscopic surgery.

Association Between Anesthetics and Postoperative Delirium in Elderly Patients Undergoing Spine Surgery: Propofol Versus Sevoflurane

STUDY DESIGNS

Retrospective Observational StudyObjectives: To compare the incidence of POD after propofol- and sevoflurane-based anesthesia in elderly patients undergoing spine surgery.

METHODS

In this study, the medical records of elderly patients ≥ 65 years of age who underwent spine surgery under total intravenous anesthesia with propofol or inhalational anesthesia with sevoflurane were reviewed. The primary outcome was the incidence of POD after propofol- and sevoflurane-based anesthesia. Secondary outcomes included postoperative 30-day complications, length of postoperative hospital stay, associations of patient characteristics, and surgery- and anesthesia-related data with the development of POD, and associations of anesthetics with clinical outcomes such as postoperative 30-day complications, and length of postoperative hospital stay.

RESULTS

Of the 281 patients, POD occurred in 29 patients (10.3%). POD occurred more frequently in the sevoflurane group than in the propofol group (15.7% vs. 5.0%, respectively; P=.003). The multivariable logistic regression analysis showed that sevoflurane-based anesthesia was associated with an increased risk of POD compared with propofol-based anesthesia (odds ratio [OR], 4.120; 95% confidence interval [CI], 1.549-10.954; P = .005), whereas anesthetics were not associated with postoperative 30-day complications and the length of postoperative hospital stay. Older age (OR, 1.242 CI, 1.130-1.366; P < .001) and higher mean pain score at postoperative day 1 (OR, 1.338 CI, 1.056-1.696; P = .016) were also associated with an increased risk of POD.

CONCLUSIONS

Propofol-based anesthesia was associated with a lower incidence of POD than sevoflurane-based anesthesia in elderly patients after spine surgery.

Delirium in older patients given propofol or sevoflurane anaesthesia for major cancer surgery: a multicentre randomised trial

BACKGROUND

Delirium is a common and disturbing postoperative complication that might be ameliorated by propofol-based anaesthesia. We therefore tested the primary hypothesis that there is less delirium after propofol-based than after sevoflurane-based anaesthesia within 7 days of major cancer surgery.

METHODS

This multicentre randomised trial was conducted in 14 tertiary care hospitals in China. Patients aged 65-90 yr undergoing major cancer surgery were randomised to either propofol-based anaesthesia or to sevoflurane-based anaesthesia. The primary endpoint was the incidence of delirium within 7 postoperative days.

RESULTS

A total of 1228 subjects were enrolled and randomised, with 1195 subjects included in the modified intention-to-treat analysis (mean age 71 yr; 422 [35%] women); one subject died before delirium assessment. Delirium occurred in 8.4% (50/597) of subjects given propofol-based anaesthesia vs 12.4% (74/597) of subjects given sevoflurane-based anaesthesia (relative risk 0.68 [95% confidence interval {CI}: 0.48-0.95]; P=0.023; adjusted relative risk 0.59 [95% CI: 0.39-0.90]; P=0.014). Delirium reduction mainly occurred on the first day after surgery, with a prevalence of 5.4% (32/597) with propofol anaesthesia vs 10.7% (64/597) with sevoflurane anaesthesia (relative risk 0.50 [95% CI: 0.33-0.75]; P=0.001). Secondary endpoints, including ICU admission, postoperative duration of hospitalisation, major complications within 30 days, cognitive function at 30 days and 3 yr, and safety outcomes, did not differ significantly between groups.

CONCLUSIONS

Delirium was a third less common after propofol than sevoflurane anaesthesia in older patients having major cancer surgery. Clinicians might therefore reasonably select propofol-based anaesthesia in patients at high risk of postoperative delirium.

CLINICAL TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR-IPR-15006209) and ClinicalTrials.gov (NCT02662257).

Propofol Suppresses Glioma Tumorigenesis by Regulating circ_0047688/miR-516b-5p/IFI30 Axis

Propofol has recently attracted increasing attention for its anti-tumor property in cancers, including glioma. Circular RNAs (circRNAs) can act as key regulators in various cancers. However, the relationship between propofol and circ_0047688 in glioma is still unclear. Cell proliferation was evaluated by Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), and colony formation assays. Cell migration and invasion were determined using transwell assay. Cell apoptosis was detected by flow cytometry. Protein levels and RNA levels were detected by western blot assay and real-time quantitative polymerase chain reaction (RT‑qPCR), respectively. The intermolecular interaction was predicted by bioinformatics analysis and verified by dual-luciferase reporter assay. A mouse xenograft model was established for in vivo experiments. Propofol inhibited cell proliferation, migration, and invasion and accelerated apoptosis in glioma cells. Circ_0047688 was upregulated in glioma tissues and cells, and propofol downregulated circ_0047688 in a dose-dependent manner. Circ_0047688 knockdown inhibited glioma cell progression and its overexpression abated the anti-tumor role of propofol in glioma cells. Moreover, miR-516b-5p was a direct target of circ_0047688, and circ_0047688 promoted glioma cell progression by sponging miR-516b-5p. In addition, IFI30 was a direct target of miR-516b-5p, and miR-516b-5p inhibited glioma cell malignant behaviors by targeting IFI30 in propofol-treated cells. Furthermore, circ_0047688 overexpression could weaken the anti-tumor role of propofol in vivo. Propofol inhibited glioma progression via modulating circ_0047688/miR-516b-5p/IFI30 axis, providing a potential therapeutic strategy for treatment of glioma.

Propofol inhibits cell apoptosis and inflammatory response in ox-LDL-induced human umbilical vein endothelial cells through the modulation of the circ_0003645/miR-149-3p/TRAF7 axis

BACKGROUND: Propofol is an anesthetic agent and can impede the progression of human diseases. Circular RNA (circRNA) circ_0003645 has been identified to promote the development of atherosclerosis (AS). This study aimed at the functional mechanism of propofol and circ_0003645 in AS. METHODS: AS cell model was established by treatment of oxidized low-density lipoprotein (ox-LDL) in human umbilical vein endothelial cells (HUVECs). Cell viability or apoptosis detection was performed by Cell Counting Kit-8 (CCK-8) assay and flow cytometry. Circ_0003645, microRNA-149-3p (miR-149-3p) and tumor necrosis factor receptor-associated factor 7 (TRAF7) levels were determined by the quantitative real-time polymerase chain reaction (qRT-PCR). Inflammatory cytokines were examined using enzyme-linked immunosorbent assay (ELISA). Protein analysis was conducted by western blot. The interaction of miR-149-3p and circ_0003645 or TRAF7 was analyzed using dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. RESULTS: Treatment of ox-LDL inhibited cell viability and enhanced apoptosis in HUVECs to establish the AS cell model. Propofol protected against cell viability inhibition and apoptosis promotion in AS cell model. Circ_0003645 expression was downregulated by propofol in AS cell model. Propofol alleviated cell apoptosis and inflammation by decreasing the circ_0003645 level. Circ_0003645 targeted miR-149-3p, and circ_0003645/miR-149-3p axis was involved in the functional regulation of propofol. TRAF7 was the target of miR-149-3p. Inhibition of miR-149-3p affected the function of propofol by upregulating the TRAF7 expression. Circ_0003645 sponged miR-149-3p to induce the upregulation of TRAF7 following propofol treatment. CONCLUSION: It has been suggested that propofol acted as an inhibitor against the ox-LDL-induced cell injury by the circ_0003645/miR-149-3p/TRAF7 axis.

Clinical Observation of Patients Undergoing Glioma Surgery under Propofol and Sevoflurane Anesthesia: A Retrospective Study

Objective

To observe the effects of propofol and sevoflurane anesthesia on patients undergoing glioma surgery.

Methods

192 patients with gliomas treated in our hospital from January 2016 to January 2021 were selected. All patients were randomly divided into observation group and control group. The observation group was given sevoflurane and the control group was given propofol. The clinical effects of the two groups were observed.

Results

Comparison of clinical indexes related to intraoperative conditions between the two groups revealed that the time of anesthesia and extubation after operation in the observation group were shorter than those in the control group, and the difference was statistically significant (P < 0.05). The amount of intraoperative bleeding in the observation group was less than that in the control group, and the difference was statistically significant (P < 0.05). There was no significant difference in intracranial operation time, operation time, fluid volume, and urine volume between the two groups (P < 05). Comparing the recovery time of anesthesia between the two groups, the recovery time of orientation and the time of eye-opening in the observation group were significantly shorter than those in the control group (P < 0.05). Comparing the consciousness and cognitive function of the two groups, the OAAS score of the observation group after extubation, before leaving the operating room and 1 hour after extubation, was significantly higher than that of the control group (P < 0.05), and the MMSE score l h after extubation was significantly higher than that of the control group (P < 0.05). Comparing the incidence of postoperative complications between the two groups, the number of cases of restlessness, urinary infection, deep vein thrombosis, and hypertension in the observation group was lower than that in the control group, with statistical significance (P < 0.05).

Conclusion

The anesthesia time and extubation time of the sevoflurane anesthesia group were shorter than that of the propofol anesthesia group, and the orientation recovery time and eye-opening time were shortened. The OAAS score of the sevoflurane anesthesia group was higher than that of the propofol anesthesia group after extubation, before extubation, and 1 hour after extubation. The probability of postoperative complications in the sevoflurane anesthesia group was lower than that in the propofol anesthesia group. Sevoflurane anesthesia may be more suitable for surgical induction of glioma patients than propofol anesthesia.

Ketamine promotes the amyloidogenic pathway by regulating endosomal pH

Ketamine is an anesthetic and addictive drug that can cause cognitive dysfunction and neuroinflammation. Studies have shown that carboxy-terminal fragment derived from β-secretase (CTF-β) and amyloid beta (Aβ), the amyloidogenic products of amyloid precursor protein (APP), can also induce neuroinflammation and impair cognitive function. However, it remains unclear whether ketamine regulates the amyloidogenic pathway. In the endosome, APP is cleaved by beta-site amyloid precursor protein cleaving enzyme 1 (BACE1), whose activity is influenced by pH. Endosomal acidification is mainly regulated by sodium hydrogen exchanger 6 (NHE6), which leaks protons out of endosomes, and vacuolar proton translocating ATPases (V-ATPase), which pump protons into endosomes. Therefore, we hypothesized that ketamine lowers the endosomal pH by reducing the endosomal NHE6 protein level, and this hyperacidification promotes the amyloidogenic pathway. We set up C57BL/6 J mouse models using 10, 20, 40, 80, and 100 mg/kg ketamine administration and SH-SY5Y cell models using 1, 10, 100, and 1000 μM ketamine administration to investigate its effects on the amyloidogenic pathway at different doses. Western blotting results showed that 100 mg/kg ketamine treatment in vivo and 1000 μM ketamine treatment in vitro increased endosomal BACE1 and CTF-β protein levels and reduced endosomal NHE6 and APP protein levels. The endosomal accumulation of BACE1 caused by ketamine administration was also observed using confocal imaging. Moreover, flow cytometry indicated that ketamine treatment lowered the endosomal pH value of SH-SY5Y cells. Later, cells were pretreated with monensin to restore the endosomal pH. Monensin did not affect amyloidogenic-related proteins or NHE6 directly; therefore, ketamine-promoted endosomal amyloidogenic processing and BACE1 accumulation were depleted by restoring endosomal acidity through monensin pretreatment. Finally, knockdown of NHE6 promoted the amyloidogenic pathway similarly and prevented further enhancement by ketamine. These results indicated that the effects of ketamine on the amyloidogenic pathway were dependent on the reduction of NHE6 and endosomal pH.

Propofol Suppresses Gastric Cancer Progression by Regulating circPDSS1/miR-1324/SOX4 Axis

Background

Propofol is a common intravenous anesthetic that exerts an antitumor role in human cancers. Circular RNAs (circRNAs) play crucial roles in the progression of various cancers. However, the relationship between propofol and circRNA decaprenyl diphosphate synthase subunit 1 (circPDSS1) in gastric cancer (GC) remains unclear.

Methods

Cell proliferation was evaluated by Cell Counting Kit-8 (CCK-8), colony formation, and 5-ethynyl-2ʹ-deoxyuridine (EdU) assays. Cell migration and invasion were assessed by transwell assay. Cell apoptosis was determined by flow cytometry. All protein levels were detected by Western blot assay. The expression levels of circPDSS1, microRNA-1324 (miR-1324), and SRY-box transcription factor 4 (SOX4) mRNA were determined by quantitative real-time PCR (qRT-PCR). The interaction between miR-1324 and circPDSS1 or SOX4 was confirmed by dual-luciferase reporter and RNA pull-down assays. The mice xenograft model was established to investigate the role of propofol and circPDSS1 in vivo.

Results

Propofol inhibited cell proliferation, migration and invasion and induced apoptosis in GC cells, which could be reversed by upregulating circPDSS1. MiR-1324 was a target of circPDSS1, and circPDSS1 promoted cell proliferation, migration and invasion and reduced apoptosis in propofol-treated cells by sponging miR-1324. Moreover, SOX4 was a direct target of miR-1324, and miR-1324 exerted anticancer role by targeting SOX4 in propofol-treated cells. CircPDSS1 acted as a sponge of miR-1324 to regulate SOX4 expression. Additionally, circPDSS1 overexpression weakened the anticancer role of propofol in vivo.

Conclusion

Propofol exerted anticancer role in GC through regulating circPDSS1/miR-1324/SOX4 axis, indicating that propofol might be an effective therapeutic medicine for GC treatment.

The Molecular Mechanisms Associated with the Effects of Propofol in a Rat Model of Pain Due to Inflammation Following Injection with Complete Freund's Adjuvant

Background

This study aimed to investigate the molecular mechanisms associated with the effects of propofol in a rat model of pain due to inflammation following subcutaneous injection with complete Freund’s adjuvant (CFA).

Material/Methods

Sprague-Dawley rats were injected subcutaneously in the paw with CFA. Propofol or saline was administered by tail vein injection. After CFA treatment for 0 hours, 4 hours, 1 day, 4 days, 7 days, and 14 days, the behavior of the rats was assessed. An enzyme-linked immunosorbent assay (ELISA) measured serum levels of proinflammatory cytokines, including tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6. Western blot and the quantitative reverse-transcription polymerase chain reaction (qRT-PCR) were used to detect levels of p38MAPK and NF-κB related mRNA and proteins, including p-p38, p38, p65, p-p65, NOD-like receptor family protein 3 (NLRP3), apoptosis-associated speck-like protein (ASC) and caspase-1 in rat spinal cord tissues.

Results

Injection of CFA significantly reduced the mechanical withdrawal threshold (MWT), thermal withdrawal latency (TWL), and frequency responses to cold stimulation. Propofol treatment significantly reduced serum levels of TNF-α, IL-1β, and IL-6. Protein expression levels of p-p38 and p-p65 were upregulated in the rat model, which were inhibited by propofol treatment. CFA injection increased the expression levels of NLRP3, ASC, and caspase-1 in the spinal cord tissues of rats, which were reduced by propofol treatment.

Conclusions

In a rat model of pain following subcutanous injection with CFA, propofol reduced CFA-induced pain and inhibited the inflammatory response through the p38MAPK-nuclear factor-κB (NF-κB) pathway and the NLRP3 inflammasome.

Theaflavins alleviate sevoflurane-induced neurocytotoxicity via Nrf2 signaling pathway

Aim: Sevoflurane could induce apoptosis of rat hippocampal neurons, while theaflavins (TFs) have antioxidant and anti-inflammatory properties. This study aims to explore whether TFs could alleviate sevoflurane-induced neuronal cell injury.Materials and methods: Cells were treated by concentration gradient of sevoflurane and TFs. Cell viability, level of reactive oxygen species (ROS) and apoptosis rate were determined by cell counting kit-8 (CCK-8) and flow cytometry, respectively. Quantitative PCR (qPCR) and western blot were performed to determine mRNA and protein expressions.Results: TFs promoted viability of cells under the treatment of sevoflurane, while it suppressed apoptosis and down-regulated ROS level in a concentration-dependent manner. TFs could also down-regulate expression levels of caspase-3 and caspase-9 and cytosol and intranuclear nuclear factor E2-related factor 2 (Nrf2) in rat hippocampal nerve cells, while it up-regulated those of heme oxygenase 1 (HO-1), NADPH quinine oxidoreductase 1 (NQO1), glutamate cysteine ligase (GCL) and peroxiredoxin 1 (Prx1).Conclusions: Our study suggests that TFs exert protective effects on sevoflurane-induced neurocytotoxicity and therefore could be used as a potential drug for treatment of neuronal injury.

Propofol attenuated TNF-α-modulated occludin expression by inhibiting Hif-1α/ VEGF/ VEGFR-2/ ERK signaling pathway in hCMEC/D3 cells

Background

The levels of tight junction proteins (TJs), especially occludin, correlate with blood-brain barrier (BBB) disruption caused by inflammation in central nervous system (CNS). It has been reported that propofol, the most commonly used anesthetic, could inhibit inflammation response in CNS. In this study, we investigated the effects of tumor necrosis factor-α (TNF-α) and propofol on occludin expression in human cerebral microvascular endothelial cell line, D3 clone (hCMEC/D3 cells), and explored the underlying mechanisms.

Methods

The hCMEC/D3 cells were treated with propofol, followed by TNF-α. The expression and phosphorylation of Hif-1α, VEGF, VEGFR-2, ERK, p38MAPK and occludin were measured by Western blot analysis. The cell viability of hCMEC/D3 cells was measured by cell counting kit-8.

Results

TNF-α (10 ng/ml, 4 h) significantly decreased the expression of occludin, which was attenuated by propofol (25 μM). TNF-α induced Hif-1α/VEGF/VEGFR-2/ERK signaling pathway, while propofol could inhibit it. TNF-α induced the phosphorylation of p38MAPK, while propofol had no effect on it. In addition, the inhibitors of Hif-1α, VEGFR-2, and ERK could reduce the effect of TNF-α on occludin expression.

Conclusion

TNF-α could decrease the expression of occludin via activating Hif-1α/ VEGF/ VEGFR-2/ ERK signaling pathway, which was attenuated by propofol.

Electronic supplementary material

The online version of this article (10.1186/s12871-019-0788-5) contains supplementary material, which is available to authorized users.

Effect of Alpinia oxyphylla-Schisandra chinensis herb pair on inflammation and apoptosis in Alzheimer's disease mice model

ETHNOPHARMACOLOGICAL RELEVANCE

Alpinia oxyphylla-Schisandra chinensis herb pair (ASHP), composed of Alpinia oxyphylla Miq. Fructus (Yizhi, in Chinese) and Schisandra chinensis (Turcz.) Baill Fructus (Wuweizi, in Chinese) has been used in many traditional Chinese prescriptions such as Yizhi Wuwei pill and Jiannao pill.

AIMS OF THE STUDY

This study was primarily dealt with studying the effects of Alpinia oxyphylla-Schisandra chinensis herb pair (ASHP) on learning and cognitive impairment in the Aβ_1-42 induced mouse model.

MATERIALS AND METHODS

The chemical composition quantitative analysis was by UPLC. Then the Y maze and Morris water maze test were used to determine the capability of ASHP extracts on improving memory. Histological changes and apoptotic features were detected by HE staining and TUNEL staining, respectively. qPCR was used to detect the changes in the mRNA of caspase3, caspase8 and caspase9 and western-blot was used to detect the changes in the levels of cleaved-caspase3, cleaved-caspase8 and cleaved-caspase9. The levels of some inflammatory factors such as IKK, IκB and NF-κB; anti-apoptotic factors such as bcl-2, bcl-xl, pro-apoptotic factors including bad, bax, p53 were assessed via immunohistochemistry (IHC) and western-blot.

RESULTS

Administration of ASHP extracts had higher spontaneous alternation ratio in the Y maze, more quadrant dwell time and shorter escape latency compared with model group in the Morris water maze. ASHP treated groups significantly inhibited NF-κB pathway and apoptosis-related pathway in the hippocampus.

CONCLUSIONS

This study demonstrated that ASHP had the ability to ameliorate abnormal changes in cognitive behavior, biochemical and histopathology induced by Aβ_1-42 in the mouse model. The powerful role of ASHP is to inhibit the NF-κB inflammatory signaling pathway and cut down the damage of apoptosis. This study revealed ASHP might be a potential therapy for cognitive and behavioral deficits.

Optimal pathways involved in the treatment of sevoflurane or propofol for patients undergoing coronary artery bypass graft surgery

The cardio-protection mechanisms of sevoflurane and propofol still remain unclear in patients undergoing coronary artery bypass grafting (CABG). We designed the present study to identify the optimal pathways through integrating differential co-expressed network (DCN)-based guilt by association (GBA) principle based on the expression data of E-GEOD-4386 downloaded from EMBL-EBI. Differentially expressed genes (DEGs) were firstly identified and then DCN and sub-DCN were established. The seed pathways were predicted through GBA principle using the area under the curve (AUC) for pathway categories, and the pathway terms with AUC >0.9 were defined as the seed pathways. KEGG pathway analysis was applied to the DEGs based on DAVIA to detect significant pathways. The final optimal pathways were identified based on the traditional pathway analysis and network-based pathway inference approach. There were 83 common, 99 sevoflurane-specific and 4 propofol-specific DEGs in the expression profile of artial samples. Finally, 8 and 4 pathway terms having the AUC >0.9 were identified and determined as the seed pathways in the propofol and sevoflurane group, respectively. TNF signaling pathway, NF-κB signaling pathway, as well as NOD-like receptor signaling pathway were the common optimal ones in these two groups. Only the pathway of cytokine-cytokine receptor interaction was unique to sevoflurane, and no pathway was specific to propofol. Our results suggested that sevoflurane and propofol might synergistically possess some cardio-protective properties in patients undergoing CABG.

Propofol suppresses growth, migration and invasion of A549 cells by down-regulation of miR-372

BACKGROUND

Propofol, a commonly used intravenous anesthetic during cancer resection surgery, has been found to exhibit tumor inhibitory effects in vitro and in vivo. The role of propofol in lung cancer has been previously reported, whereas its action mechanism remains unclear. This study further investigated the effects of propofol on lung cancer A549 cell growth, migration and invasion, as well as the underlying mechanisms.

METHODS

Cell viability, proliferation, migration, invasion and apoptosis were assessed by CCK-8 assay, BrdU assay, two chamber transwell assay and flow cytometry, respectively. The regulatory effect of propofol on microRNA-372 (miR-372) expression in A549 cells was analyzed by qRT-PCR. Cell transfection was used to change the expression of miR-372. The protein expression of key factors involving in cell proliferation, apoptosis, migration and invasion, as well as Wnt/β-catenin and mTOR pathways were analyzed by western blotting.

RESULTS

Propofol inhibited lung cancer A549 cell viability, proliferation, migration, and invasion, but promoted cell apoptosis. Moreover, miR-372 was down-regulated in propofol-treated A549 cells. Overexpression of miR-372 abrogated the effects of propofol on proliferation, migration, invasion and apoptosis of A549 cells. Knockdown of miR-372 had opposite effects. Furthermore, propofol suppressed Wnt/β-catenin and mTOR signaling pathways by down-regulating miR-372.

CONCLUSION

Propofol inhibits growth, migration and invasion of lung cancer A549 cells at least in part by down-regulating miR-372 and then inactivating Wnt/β-catenin and mTOR pathways.

Evaluation of cytotoxicity of propofol and its related mechanism in glioblastoma cells and astrocytes

Propofol (2,6-diisopropylphenol), one of the extensively and commonly used anesthetic agents, has been shown to affect the biological behavior of various models. Previous researches have shown that propofol-induced cytotoxicity might cause anticancer effect in different cells. However, the mechanisms underlying the effect of propofol on cytotoxicity is still elusive in human glioblastoma cells. The aims of this study were to evaluate effects of propofol on cytotoxicity, cell cycle distribution and ROS production, and establish the relationship between oxidative stress and cytotoxicity in GBM 8401 human glioblastoma cells and DI TNC1 rat astrocytes. Propofol (20-30 μM) concentration-dependently induced cytotoxicity, cell cycle arrest, and increased ROS production in GBM 8401 cells but not in DI TNC1 cells. In GBM 8401 cells, propofol induced G2/M phase cell arrest, which affected the CDK1, cyclin B1, p53, and p21 protein expression levels. Furthermore, propofol induced oxygen stresses by increasing O2- and H₂ O₂ levels but treatment with the antioxidant N-acetylcysteine (NAC) partially reversed propofol-regulated antioxidative enzyme levels (superoxide dismutase, catalase, and glutathione peroxidase). Most significantly, propofol induced apoptotic effects by decreasing Bcl-2 but increasing Bax, cleaved caspase-9/caspase-3 levels, which were partially reversed by NAC. Moreover, the pancaspase inhibitor Z-VAD-FMK also partially prevented propofol-induced apoptosis. Together, in GBM 8401 cells but not in DI TNC1 cells, propofol activated ROS-associated apoptosis that involved cell cycle arrest and caspase activation. These findings indicate that propofol not only can be an anesthetic agent which reduces pain but also has the potential to be used for the treatment of human glioblastoma.

Impact of propofol on renal ischemia/reperfusion endoplasmic reticulum stress

Purpose:

To investigate the protective mechanisms of propofol (Pro) on renal ischemia/reperfusion (I/R) injury by studying its impact on renal I/R endoplasmic reticulum stress.

Methods:

Eighteen male Sprague-Dawley rats (SD rats) were randomly divided into three groups: the I/R group, the Pro pretreatment group, and the control group, and corresponding treatments were performed. The levels of serum creatinine (Cr) and blood urea nitrogen (BUN) of each group were detected. The expression levels of CCAAT-enhancer-binding protein (C/EBP) homology protein (CHOP) and caspase-12 protein within renal tissue samples were detected by western blot.

Results:

The periodic acid-Schiff (PAS) staining was performed to observe the morphological changes within the renal tissues, and the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assay was performed to detect the presence of renal apoptosis. The Pro pretreatment significantly reduced the serum Cr and BUN levels, as well as the expressions levels of CHOP and caspase-12 protein inside the kidney of I/R rats, improving renal pathological injury and reducing the I/R-induced renal apoptosis.

Conclusion:

Propofol could downregulate the expression of stress-apoptotic proteins CHOP and caspase-12 in the endoplasmic reticulum, thus reducing renal I/R injury.

Lasting impact of general anaesthesia on the brain: mechanisms and relevance

General anaesthesia is usually considered to safely induce a reversible brain state allowing the performance of surgery under optimal conditions. An increasing number of clinical and experimental observations, however, suggest that anaesthetic drugs, especially when they are administered at the extremes of age, can trigger long-term morphological and functional alterations in the brain. Here, we review available mechanistic data linking general-anaesthesia exposure to impaired cognitive performance in both young and mature nervous systems. We also provide a critical appraisal of the translational value of animal models and highlight the important challenges that need to be addressed to strengthen the link between laboratory work and clinical investigations in the field of anaesthesia-neurotoxicity research.

Cognitive decline in the elderly after surgery and anaesthesia: results from the Oxford Project to Investigate Memory and Ageing (OPTIMA) cohort

Concerns have been raised about the effects on cognition of anaesthesia for surgery, especially in elderly people. We recorded cognitive decline in a cohort of 394 people (198 women) with median (IQR) age at recruitment of 72.6 (66.6–77.8) years, of whom 109 had moderate or major surgery during a median (IQR) follow‐up of 4.1 (2.0–7.6) years. Cognitive decline was more rapid in people who on recruitment were: older, p = 0.0003; male, p = 0.027; had worse cognition, p < 0.0001; or carried the ε4 allele of apoliprotein E (APOEε4), p = 0.008; and after an operation if cognitive impairment was already diagnosed, p = 0.0001. Cognitive decline appears to accelerate after surgery in elderly patients diagnosed with cognitive impairment, but not other elderly patients.

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Autophagy activation prevents sevoflurane-induced neurotoxicity in H4 human neuroglioma cells

AIM

The inhaled anesthetic sevoflurane may induce cognitive impairment in both animals and humans. Previous study has shown that sevoflurane triggers ER stress and may lead to apoptosis in rat hippocampal neurons. In this study, we examined whether sevoflurane caused autophagy and its contributions to sevoflurane induced neuronal cell injury.

METHODS

H4 human neuroglioma cells were exposed to 4.1% sevoflurane for 6 h. Cell viability and apoptosis ratio were assessed using a CCK8 kit and flow cytometry, respectively. Autophagosomes in the cells were detected using GFP-LC3 plasmid transfection or transmission electronic microscopy. The expression of LC3B, p62/SQSTM, C/EBP homologous protein (CHOP) and glucose-related protein 78 (GRP78) was assessed with Western blotting.

RESULTS

Sevoflurane treatment induced apoptosis and markedly increased the LC3-II level and GFP-LC3 puncta number, decreased p62 expression in H4 cells. Activation of autophagy by rapamycin (1 μmol/L) significantly reduced sevoflurane-induced apoptosis and increased cell viability, whereas inhibition of autophagy with 3-MA (5 mmol/L) caused the opposite effects. Furthermore, sevoflurane treatment markedly increased the expression of CHOP and GRP78, two hallmark proteins of ER stress. Inhibition of ER stress by 4-phenylbutyrate (500 μmol/L) abrogated sevoflurane-induced autophagy and apoptosis, and improved the viability. Moreover, sevoflurane-stimulated expression of CHOP and GRP78 was inhibited by rapamycin, but further enhanced by 3-MA.

CONCLUSION

Sevoflurane treatment induces ER stress and activates autophagy, which antagonizes sevoflurane-induced apoptosis in H4 human neuroglioma cells. The results suggest that autophagy may be a potential therapeutic target in preventing sevoflurane-induced neurotoxicity.

Effect of Continuous Propofol Infusion in Rat on Tau Phosphorylation with or without Temperature Control

Several studies suggest a relationship between anesthesia-induced tau hyperphosphorylation and the development of postoperative cognitive dysfunction. This study further characterized the effects of continuous propofol infusion on tau protein phosphorylation in rats, with or without temperature control. Propofol was administered intravenously to 8-10-week-old male Sprague-Dawley rats and infused to the loss of the righting reflex for 2 h continuously. Proteins from cortex and hippocampus were examined by western blot and immunohistochemistry. Rectal temperature was significantly decreased during propofol infusion. Propofol with hypothermia significantly increased phosphorylation of tau at AT8, AT180, Thr205, and Ser199 in cortex and hippocampus except Ser396. With temperature maintenance, propofol still induced significant elevation of AT8, Thr205, and Ser199 in cortex and hippocampus; however, increase of AT180 and Ser396 was only found in hippocampus and cortex, respectively. Differential effects of propofol with or without hypothermia on multiple tau related kinases, such as Akt/GSK3β, MAPK pathways, or phosphatase (PP2A), were demonstrated in region-specific manner. These findings indicated that propofol increased tau phosphorylation under both normothermic and hypothermic conditions, and temperature control could partially attenuate the hyperphosphorylation of tau. Further studies are warranted to determine the long-term impact of propofol on the tau pathology and cognitive functions.

Induction of TNF-α signaling cascade in neonatal rat brain during propofol anesthesia

Propofol anesthesia can trigger pro- and anti-apoptotic signaling pathways in the rat brain. In our previous work, we demonstrated that propofol causes widespread apoptotic neurodegeneration in 7-postnatal-day-old (PND7) but not in PND14 rat neurons. The mechanism responsible for these opposing outcomes is unknown, apparently linked to the specific stage of brain development. The present study aims to elucidate the anti-apoptotic process that is activated in the cortex and thalamus of PND14 Wistar rats during the first 48 h after the onset of propofol anesthesia. We showed that the expression of tumor necrosis factor-α (TNF-α) and several components of its pathway, TNFR1 and caspase-8, was significantly increased in the cortex and thalamus. Nuclear factor kappa B (NF-κB) p65 was downregulated in the cortex and upregulated in the thalamus. The expression of c-Fos was upregulated only in the cortex, showing opposed profile compared to NF-κB p65. Double immunofluorescence staining revealed the colocalization of NF-κB p65 with neuronal marker (NeuN), but with predominantly cytoplasmic localization. Finally, X-linked inhibitor of apoptosis protein (XIAP) was upregulated in both examined structures. Immunohistochemical staining with Iba-1 revealed that the treatment did not induce changes in microglial morphology. Our results (i) reveal that the simultaneous activation of pro- and anti-apoptotic signaling occurs after propofol anesthesia, and (ii) pinpoint the potential neuroprotective role of XIAP in anesthesia-induced neurotoxicity.