Sevoflurane preconditioning improving cerebral focal ischemia-reperfusion damage in a rat model via PI3K/Akt signaling pathway

Potential of natural products in osteosarcoma treatment: Focus on molecular mechanisms

Osteosarcoma is the most frequent type of bone cancer found in children and adolescents, and commonly arises in the metaphyseal region of tubular long bones. Standard therapeutic approaches, such as surgery, chemotherapy, and radiation therapy, are used in the management of osteosarcoma. In recent years, the mortality rate of osteosarcoma has decreased due to advances in treatment methods. Today, the scientific community is investigating the use of different naturally derived active principles against various types of cancer. Natural bioactive compounds can function against cancer cells in two ways. Firstly they can act as classical cytotoxic compounds by non-specifically affecting macromolecules, such as DNA, enzymes, and microtubules, which are also expressed in normal proliferating cells, but to a greater extent by cancer cells. Secondly, they can act against oncogenic signal transduction pathways, many of which are activated in cancer cells. Some bioactive plant-derived agents are gaining increasing attention because of their anti-cancer properties. Moreover, some naturally-derived compounds can significantly promote the effectiveness of standard chemotherapy drugs, and in certain cases are able to ameliorate drug-induced adverse effects caused by chemotherapy. In the present review we summarize the effects of various naturally-occurring bioactive compounds against osteosarcoma.

Phosphoinositide-3-Kinase/Akt-Endothelial Nitric Oxide Synthase Signaling Pathway Mediates the Neuroprotective Effect of Sevoflurane Postconditioning in a Rat Model of Hemorrhagic Shock and Resuscitation

BACKGROUND

Although extensive reports have demonstrated the neuroprotection of sevoflurane postconditioning in cases of focal and global cerebral ischemia/reperfusion, the underlying mechanisms are not completely elucidated. This study investigated whether this effect is related to endothelial nitric oxide synthase (eNOS) and mediated by the phosphoinositide-3-kinase pathway in a rat model of hemorrhagic shock and resuscitation.

METHODS

Adult male Sprague Dawley rats were subjected to hemorrhagic shock for 60 minutes and then resuscitation for 30 minutes in experimental groups. Sevoflurane postconditioning was performed at the beginning of resuscitation to completion. At 24 hours after resuscitation, the brain infarct volume was evaluated by 2,3,5-triphenyltetrazolium chloride staining. The neuronal morphological changes and apoptosis were determined by hematoxylin and eosin staining and immunohistochemistry analysis, respectively. The activity of phosphorylated Akt and eNOS was evaluated by Western blot analysis.

RESULTS

Brain injuries such as the cerebral infarct volume and pathological neuronal changes as well as cell apoptosis were observed in the hippocampus after hemorrhagic shock and resuscitation. Postconditioning with 2.4% sevoflurane significantly attenuated brain injuries. Wortmannin prevented the improvements of neuronal characteristics elicited by sevoflurane postconditioning as well as the hyperactivity of eNOS and phosphorylated Akt.

CONCLUSIONS

Sevoflurane postconditioning could attenuate brain injury induced by hemorrhagic shock and resuscitation, and this neuroprotective effect may be partly by upregulation of eNOS through the phosphoinositide-3-kinase/Akt signaling pathway.

Down-regulation of NAA10 mediates the neuroprotection induced by sevoflurane preconditioning via regulating ERK1/2 phosphorylation

OBJECTIVE

In the present study, the regulation mechanism of NAA10 (N-Alpha-Acetyltransferase 10) in sevoflurane preconditioning induced neuroprotective effect was explored.

METHODS

Firstly, si-NAA10 or negative control (NC) were constructed for cell transfection and injected into intracerebroventricular of rats. Oxygen-glucose deprivation/reperfusion (OGD/R) model in vitro and middle cerebral artery occlusion (MCAO) model in vivo were established to simulate cerebral I/R injury. QRT-PCR analysis and western blotting assay were performed to assess the expression of NAA10. TTC staining, neurological evaluation and cell counting kit-8 (CCK-8) were performed to evaluate the effect of NAA10 on sevoflurane induced neuroprotection. TUNEL assay and flow cytometry were used to detect the apoptosis in vivo and in vitro.

RESULTS

It showed that sevoflurane preconditioning increased the expression of NAA10 in MCAO rats. TTC staining, TUNEL assay and neurological evaluation results suggested that si-NAA10 attenuated the neuroprotective effect of sevoflurane preconditioning against MCAO. CCK-8 assay, flow cytometry, qRT-PCR and western blot results showed that NAA10 mediated sevoflurane preconditioning-induced neuroprotection in vitro. Furthermore, western blot results showed that down-regulation of NAA10 could reverse the attenuation of ERK1/2 phosphorylation induced by sevoflurane preconditioning in vivo or in vitro.

CONCLUSION

Down-regulation of NAA10 regulated ERK1/2 phosphorylation mediating sevoflurane preconditioning induced neuroprotective effects. The results revealed the regulatory mechanism of NAA10 in the neuroprotective effect of sevoflurane preconditioning.

THAP11 down-regulation may contribute to cardio-protective effects of sevoflurane anesthesia: Evidence from clinical and molecular evidence

This study aimed to explore the potential target of the cardio-protective effect induced by sevoflurane anesthesia based on evidence from clinical samples and in vitro model. Forty patients undergoing mitral valve replacement were randomly allocated to receive sevoflurane or propofol-based anesthesia. Atrial muscle specimens were collected from all patients, of which 5 were used to perform transcriptomics analysis. The cTn-I concentration was tested before, at the end of, and 24 h after surgery. In in vitro study, the expression level of the identified target gene, i.e., THAP11, was studied in H9C2 cells treated with sevoflurane or propofol. Then, we studied cell viability using CCK-8 staining, apoptosis by using flow cytometry, and cell death by lactic acid dehydrogenase (LDH) detection in H9C2 cells exposed to oxygen glucose deprivation/reoxygenation (OGD/R) injury. THAP11 was the most significantly down-regulated gene in the transcriptomics analysis (P < 0.001), as confirmed in validation samples (P = 0.006). THAP11 mRNA levels in atrial muscle specimens were positively associated with cTn-I levels at 24-h postoperatively (determination coefficient = 0.564; P < 0.001). Sevoflurane treatment down-regulated THAP11 in H9C2 cell models, which promoted cell viability, inhibited cell apoptosis, and death in the OGD/R injury cell model. Up-regulation of THAP11 reduced the protective effect of sevoflurane treatment against OGD/R injury. Sevoflurane anesthesia down-regulates the expression of THAP11, which contributes to a cardio-protective effect. THAP11 down-regulation promotes cell viability, and inhibits cell apoptosis and death, thereby protecting again myocardial injury; it may therefore be a novel target for perioperative cardio-protection.

Involvement of Nrf-2/HO-1 pathway in sevoflurane-induced cognitive improvement in rats with traumatic brain injury

Traumatic brain injury (TBI) is an increasingly common emergency disease that usually leads to prolonged physical and cognitive impairments. In this study, we investigated if sevoflurane could induce cognitive improvement in TBI rats. Rats were subjected to head trauma induced by a fluid percussion device. A two-hour exposure to 3% sevoflurane was performed in a chamber immediately after TBI. Sevoflurane inhalation reduced the neurological and cognitive deficits induced by TBI with ameliorated synaptic injuries in the hippocampus. Moreover, after sevoflurane treatment, the expression of nuclear factor erythroid-2-related factor-2 (Nrf-2) and hemeoxygenase-1 (HO-1) in the hippocampus was enhanced 1 d after TBI and maintained at high levels 14 days later, and oxidative stress induced by TBI was inhibited. However, the HO-1 inhibitor, Zinc protoporphyrin (ZnPP), used to demonstrate the involvement of HO-1, suppressed the protective effect of sevoflurane. These results indicate that sevoflurane administered immediately after TBI may protect against TBI-induced synaptic and cognitive impairments by promoting the antioxidant Nrf-2/HO-1 pathway. Sevoflurane may be a promising anesthetic for patients with TBI.

Berberine alleviates rotenone-induced cytotoxicity by antioxidation and activation of PI3K/Akt signaling pathway in SH-SY5Y cells

Berberine, an isoquinoline alkaloid isolated from traditional Chinese medicine, has been widely studied for its efficacy in the treatment of neurodegenerative diseases. However, berberine-mediated neuroprotection in the pathogenesis of Parkinson's disease is still uncertain. In this study, the effects of berberine on rotenone-induced neurotoxicity in SH-SY5Y cells were investigated. The results showed that berberine treatment significantly alleviated rotenone-induced decrease in the cell viability in SH-SY5Y cells. Further studies demonstrated that berberine suppressed the production of intracellular reactive oxygen species, restored the mitochondrial transmembrane potential, increased Bcl-2/Bax ratio, and decreased caspase-3 activation that induced by rotenone. Furthermore, berberine also restored the phosphorylation of Akt, which was downregulated by rotenone in SH-SY5Y cells. These results suggest that berberine protects rotenone-treated SH-SY5Y cells by antioxidation and activation of PI3K/Akt signaling pathway.

Sedating Mechanically Ventilated COVID-19 Patients with Volatile Anesthetics: Insights on the Last-Minute Potential Weapons

Coronavirus Disease 2019 (COVID-19) has spread globally with the number of cases exceeding seventy million. Although trials on potential treatments of COVID-19 Acute Respiratory Distress Syndrome (ARDS) are promising, the introduction of an effective therapeutic intervention seems elusive. In this review, we explored the potential therapeutic role of volatile anesthetics during mechanical ventilation in the late stages of the disease. COVID-19 is thought to hit the human body via five major mechanisms: direct viral damage, immune overactivation, capillary thrombosis, loss of alveolar capillary membrane integrity, and decreased tissue oxygenation. The overproduction of pro-inflammatory cytokines will eventually lead to the accumulation of inflammatory cells in the lungs, which will lead to ARDS requiring mechanical ventilation. Respiratory failure resulting from ARDS is thought to be the most common cause of death in COVID-19. The literature suggests that these effects could be directly countered by using volatile anesthetics for sedation. These agents possess multiple properties that affect viral replication, immunity, and coagulation. They also have proven benefits at the molecular, cellular, and tissue levels. Based on the comprehensive understanding of the literature, short-term sedation with volatile anesthetics may be beneficial in severe stages of COVID-19 ARDS and trials to study their effects should be encouraged.

Protective effects of sevoflurane in cerebral ischemia reperfusion injury: a narrative review

Ischemia/reperfusion (I/R) injury is a phenomenon that the reperfusion of ischemic organs or tissues aggravates their damage, which poses a serious health threat and economic burden to the world. I/R gives rise to a series of physiological and pathological world, including inflammatory response, oxidative stress, brain edema, blood-brain barrier destruction, and neuronal death. Therefore, finding effective treatment measures is extremely important to the recovery of I/R patients and the improvement of long-term quality of life. Sevoflurane is an important volatile anesthetic which has been reported to reduce myocardial I/R damage and infarct size. Sevoflurane also has anti-inflammatory and neuroprotective effects. As reported sevoflurane treatment could reduce nerve function injury, cerebral infarction volume and the level of inflammatory factors. At the same time, there is evidence that sevoflurane can reduce neuron apoptosis and antioxidant stress. The protective effect of sevoflurane in brain injury has been proved to be existed in several aspects, so that a comprehensive understanding of its neuroprotective effect is helpful to exploit new treatment paths for I/R, provide clinicians with new clinical treatment decisions, contribute to the effective treatment of I/R patients and the improvement of quality of life after I/R healing.

Neuroprotective effects of a protein tyrosine phosphatase inhibitor against hippocampal excitotoxic injury

Neuronal excitotoxicity is the neuronal cell death arising from prolonged exposure to glutamate and the associated excessive influx of ions into the cell. Sodium orthovanadate (Na₃VO₄,) competitively inhibits the protein tyrosine phosphatases that affect intracellular protein phosphorylation. No study has examined the role of protein tyrosine phosphatases in kainic acid (KA)-induced excitotoxic injury using sodium orthovanadate. Thus, the present study was conducted to determine the neuroprotective effects of sodium orthovanadate on KA-induced neuronal death in organotypic hippocampal slice culture. We also performed an in vivo electrophysiology study in Sprague-Dawley rats to observe the function of surviving cells after sodium orthovanadate treatment in KA-induced excitotoxicity. Rats were anaesthetized with sodium pentobarbital and KA was injected unilaterally in CA3 of the hippocampus by microinjection-cannula. Neuronal cell death, as assessed by propidium iodide uptake, was reduced by 10 and 25 μM sodium orthovanadate treatment (24 and 48 h) compared with the KA-only group. Sodium orthovanadate enhanced survival signals by increasing levels of phospho-Akt and superoxide dismutase. In addition, sodium orthovanadate treatment reduced calcineurin level for neuronal protection, which regulates activation of cellular calcium caused by KA-induced injury. In vivo results showed that sodium orthovanadate treatment elicited resistance to KA-induced behavior seizures and significantly reduced the duration of epileptiform discharges. In addition, sodium orthovanadate treatment (25 mM) significantly prevented the increase in power spectra induced by KA injection. These results suggest that sodium orthovanadate decreases the acute effects of KA, thereby inducing neuroprotective effects with reduced reactive oxygen species and cellular Ca²⁺. Thus, sodium orthovanadate may protect hippocampal neurons against excitotoxicity, and surviving neurons may function to reduce seizures.

Sevoflurane Preconditioning plus Postconditioning Decreases Inflammatory Response with Hemodynamic Recovery in Experimental Liver Ischemia Reperfusion

Objective

The inhalation anesthetic sevoflurane has presented numerous biological activities, including anti-inflammatory properties and protective effects against tissue ischemic injury. This study investigated the metabolic, hemodynamic, and inflammatory effects of sevoflurane pre- and postconditioning for short periods in the rescue of liver ischemia-reperfusion (IR) injury using a rat model.

Materials and Methods

Twenty Wistar rats were divided into four groups: sham group, control ischemia group (partial warm liver ischemia for 45 min followed by 4 h of reperfusion), SPC group (administration of sevoflurane 2.5% for 15 min with 5 min of washout before liver IR), and SPPoC group (administration of sevoflurane 2.5% for 15 min before ischemia and 20 min during reperfusion).

Results

All animals showed a decrease in the mean arterial pressure (MAP) and portal vein blood flow during ischemia. After 4 h of reperfusion, only the SPPoC group had MAP recovery. In both the SPC and SPPoC groups, there was a decrease in the ALT level and an increase in the bicarbonate and potassium serum levels. Only the SPPoC group showed an increase in the arterial blood ionized calcium level and a decrease in the IL-6 level after liver reperfusion. Therefore, this study demonstrated that sevoflurane preconditioning reduces hepatocellular injury and acid-base imbalance in liver ischemia. Furthermore, sevoflurane postconditioning promoted systemic hemodynamic recovery with a decrease in inflammatory response.

Effect of sevoflurane preconditioning on astrocytic dynamics and neural network formation after cerebral ischemia and reperfusion in rats

Astrocytes, the major component of blood-brain barriers, have presented paradoxical profiles after cerebral ischemia and reperfusion in vivo and in vitro. Our previous study showed that sevoflurane preconditioning improved the integrity of blood-brain barriers after ischemia and reperfusion injury in rats. This led us to investigate the effects of sevoflurane preconditioning on the astrocytic dynamics in ischemia and reperfusion rats, in order to explore astrocytic cell-based mechanisms of sevoflurane preconditioning. In the present study, 2,3,5-triphenyltetrazolium chloride staining and Garcia behavioral scores were utilized to evaluate cerebral infarction and neurological outcome from day 1 to day 3 after transient middle cerebral artery occlusion surgery. Using immunofluorescent staining, we found that sevoflurane preconditioning substantially promoted the astrocytic activation and migration from the penumbra to the infarct with microglial activation from day 3 after middle cerebral artery occlusion. The formation of astrocytic scaffolds facilitated neuroblasts migrating from the subventricular zone to the lesion sites on day 14 after injury. Neural networks increased in the infarct of sevoflurane preconditioned rats, consistent with decreased infarct volume and improved neurological scores after ischemia and reperfusion injury. These findings demonstrate that sevoflurane preconditioning confers neuroprotection, not only by accelerating astrocytic spatial and temporal dynamics, but also providing astrocytic scaffolds for neuroblasts migration to ischemic regions, which facilitates neural reconstruction after brain ischemia.

Neuroprotective effects of protein tyrosine phosphatase 1B inhibitor on cerebral ischemia/reperfusion in mice

Akt (Protein kinase B, PKB), a serine/threonine kinase, plays a critical role in cell development, growth, and survival. Akt phosphorylation mediates a neuroprotective effect against ischemic injury. Recently, a protein-tyrosine phosphatase-1B (PTP1B) inhibitor (KY-226) was developed to elicit anti-diabetic and anti-obesity effects via enhancement of insulin signaling. Previously, we reported that the nonselective PTP1B inhibitor, sodium orthovanadate, rescued neurons from delayed neuronal death during brain ischemia. In this study, we confirmed the ameliorative effects of KY-226 on ischemia/reperfusion (I/R) injury using a murine model of middle cerebral artery occlusion (MCAO). ICR mice were subjected to MCAO for 2 h followed by reperfusion. Although KY-226 permeability was poor through the blood-brain barrier (BBB) of normal mice, it could penetrate through the BBB of mice after I/R insult. Intraperitoneal KY-226 administration elicited dose-dependent reductions in infarcted brain areas and improved neurological deficits. The neuroprotective effects of KY-266 were obtained when administered within 0.5 h after reperfusion. KY-226 (10 mg/kg) also restored reduced Akt phosphorylation and eNOS phosphorylation (Ser-1177) levels following I/R insult. Moreover, 10 mg/kg of KY-226 improved I/R-induced decreased extracellular signal-regulated kinase (ERK) phosphorylation. Furthermore, KY-226 attenuated the generation of reactive oxygen species (ROS) in mouse cortex. These results suggest that KY-226 may act as a novel therapeutic candidate for ischemic stroke. Activation of Akt and ERK possibly underlie the neuroprotective mechanism of KY-226.

Erzhi Pill® Protected Experimental Liver Injury Against Apoptosis via the PI3K/Akt/Raptor/Rictor Pathway

Erzhi Pill (EZP) is one of the basic prescriptions for treating liver diseases in traditional Chinese medicine. However, its mechanism of action is still undefined. The PI3K/AKT/Raptor/Rictor signaling pathway is closely related to apoptosis and plays a significant role in the pathogenesis of liver disease. To define the mechanism of the hepatoprotective effect of EZP in the treatment of liver disease, hepatic injury induced by 2-acetylaminofluorene/partial hepatectomy was treated by EZP for 14 days. The therapeutic effect of EZP was confirmed by the decreased production of aspartate aminotransferase and alanine aminotransferase, recovery of pathological liver injury, followed by inhibition of pro-inflammatory cytokines and transforming growth factor-β1. Bromodeoxyuridine assay and TUNEL staining indicated that apoptosis was suppressed and the numbers of cells in S phase and G0/G1phase were decreased. The crucial proteins in the PI3K/AKT/Raptor/Rictor signaling pathway were deactivated in rats with experimental liver injury treated by EZP. These results indicated that the hepatoprotective effect of EZP via inhibition of hepatocyte apoptosis was closely related to repression of the PI3K/Akt/Raptor/Rictor signaling pathway.

Comparison of volatile anesthetic-induced preconditioning in cardiac and cerebral system: molecular mechanisms and clinical aspects

Volatile anesthetic-induced preconditioning (APC) has shown to have cardiac and cerebral protective properties in both pre-clinical models and clinical trials. Interestingly, accumulating evidences demonstrate that, except from some specific characters, the underlying molecular mechanisms of APC-induced protective effects in myocytes and neurons are very similar; they share several major intracellular signaling pathways, including mediating mitochondrial function, release of inflammatory cytokines and cell apoptosis. Among all the experimental results, cortical spreading depolarization is a relative newly discovered cellular mechanism of APC, which, however, just exists in central nervous system. Applying volatile anesthetic preconditioning to clinical practice seems to be a promising cardio-and neuroprotective strategy. In this review, we also summarized and discussed the results of recent clinical research of APC. Despite all the positive experimental evidences, large-scale, long-term, more precisely controlled clinical trials focusing on the perioperative use of volatile anesthetics for organ protection are still needed.

The effect of sevoflurane on retinal angiogenesis in a mouse model of oxygen-induced retinopathy

BACKGROUND

Sevoflurane is commonly used in general anesthesia for premature neonates. The main mechanism of retinopathy of prematurity (ROP) is increased levels of vascular endothelial growth factor (VEGF). For the investigation of sevoflurane's effect on angiogenesis, the angiogenesis and VEGF expression in the retina were measured after administering sevoflurane in an oxygen-induced retinopathy mice model.

MATERIALS AND METHODS

The mice were divided into the normoxic group (Nc and Ns group; n = 6) and the ROP group (C, Rc, and Rs group; n = 6). Rc group were exposed to 75% oxygen for 5 days beginning on postnatal day (P) 7, and then returned to room air. Age-matched mice in the C group were exposed to room air. To observe angiogenesis of the retina, the mice were sacrificed on P16. The Rs group was exposed to 2 vol% sevoflurane for 2 h on P12, P13, and P14 with 40% oxygen.

RESULTS

The angiogenic area and the spreading distance of vessels on P4 were statistically decreased in the Ns group, compared to the Nc group. The avascular area on P16 was significantly increased and the expression of VEGF was suppressed in the Rs group compared to the Rc group.

CONCLUSIONS

Sevoflurane can inhibit retinal angiogenesis via suppressing VEGF expression in an OIR mice model with exposure to relative hypoxia. Nevertheless, it is still difficult to apply the results of this study immediately to humans because of the heterogeneity of responses to sevoflurane.

Effects of sevoflurane preconditioning on microglia/macrophage dynamics and phagocytosis profile against cerebral ischemia in rats

AIM

The effects of sevoflurane on microglia/macrophages, promoting or suppressing their activation, remains controversy. We aimed to determine whether sevoflurane preconditioning can protect brain via changing microglia/macrophage dynamics and phagocytosis profile after ischemia.

METHODS

The impact of sevoflurane preconditioning was evaluated on microglia/macrophage migration, phagocytosis and proliferation altogether from day 1 to day 7 after transient middle cerebral arterial occlusion (tMCAO) in rats.

RESULTS

Sevoflurane preconditioning was identified to accelerate microglia/macrophage migrating to and invasion in the ischemic core from day 1 to day 5 after damage. Significant accumulation of amoeboid and phagocytic microglia/macrophages was observed in sevoflurane group from day 3 to day 5 after ischemia injury. In addition, sevoflurane pretreatment also promoted the proliferation of microglia/macrophage (Iba1⁺ /Ki67⁺ ) dramatically in ischemic core on day 3 postinsult.

CONCLUSIONS

Our current study has identified the impact of sevoflurane preconditioning on microglia/macrophage dynamics, including its migration, phagocytosis, and proliferation at early stage after brain ischemia and reperfusion. Sevoflurane might enhance microglia/macrophage activation and promote brain repair. These results could help to approach more relevant microglia/macrophage cell-based strategy for human stroke therapy.

Paclitaxel alleviated liver injury of septic mice by alleviating inflammatory response via microRNA-27a/TAB3/NF-κB signaling pathway

Excessive inflammatory response and apoptosis play an important role in the sepsis-induced liver injury. Paclitaxel, a diterpene alkaloid of Taxus brevifolia, is widely used as an anti-tumor drug and shows protective effects on acute lung and kidney injury. However, whether it has a protective effect against sepsis-induced liver injury has not been reported. The objective of this study was to investigate the protective effects of paclitaxel in septic liver injury in mice and associated molecular mechanisms. Our results showed that paclitaxel treatment improved LPS-induced liver injury, as evidenced by the reduced aminotransferase activity, histological scores and apoptosis in the liver tissues. This was accompanied by the alleviating of inflammation and oxidative stress, such as decreased levels of tumor necrosis factor alpha (TNF-α), interleukin-1 (IL-6) interleukin-1β (IL-1β) and malondialdehyde (MDA) and increased levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-px) in serum and liver tissues. Subsequent microarray and qRT-PCR analysis further showed that miR-27a was significantly decreased in mice with sepsis, which was recovered by paclitaxel pretreatment. Antagomir-miR-27a suppressed the therapeutic effects of paclitaxel in mice liver injury model via promoting inflammatory response. Of note, TAB3, which participated in the activation of the NF-κB signaling pathway, was identified as a direct target of miR-27 by luciferase reporter gene assays. Then, we revealed a reverse relationship between miR-27a expression levels and TAB3 mRNA levels in liver tissues from septic mice. Furthermore, paclitaxel treatment significantly decreased the expression of NF-κB p65, but increased inhibitor of nuclear factor-κB-α (IκBα) protein levels in septic mice, suggesting the inactivation of NF-κB signaling pathway. Notably, the inhibitory effects of paclitaxel on NF-κB signaling pathway were reversed by antagomir-miR-27a. Our data indicated that paclitaxel significantly attenuated septic induced liver injury through reducing inflammatory response via miR-27a/TAB3/NF-κB signaling 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.

Terlipressin protects intestinal epithelial cells against oxygen-glucose deprivation/re-oxygenation injury via the phosphatidylinositol 3-kinase pathway

Intestinal ischemia/reperfusion (I/R) injury is associated with a high morbidity and mortality. Vasopressin is administered to critically ill patients with potential intestinal I/R. However, the impacts of vasopressin on intestinal epithelia under ischemic/anoxic conditions remain unclear. The aim of the present study was to evaluate the effects of terlipressin, a highly selective vasopressin V1 receptor agonist, on oxygen and glucose deprivation/re-oxygenation (OGD/R)-induced damage in intestinal epithelial cells (IEC-6). IEC-6 cells were subjected to OGD for 4 h, followed by 4 h re-oxygenation. Terlipressin was incubated with cells for 4 h following OGD. Following OGD/R, IEC-6 cell viability, proliferation and apoptosis, as well as cell cycle dynamics, were assessed and the levels of tumor necrosis factor (TNF)-α and 15-F2t-isoprostane in the culture medium were measured. In addition, wortmannin, a specific phosphatidylinositol 3-kinase (PI3K) inhibitor, was administrated to investigate the mechanism of terlipressin action. The results demonstrated that IEC-6 cell viability and proliferation decreased, and cell apoptosis increased, following OGD/R. However, IEC-6 cell cycle dynamics did not significantly change 4 h after OGD. Incubation with 25 nM terlipressin significantly improved cell viability, proliferation and apoptosis. Furthermore, terlipressin inhibited the secretion of TNF-α and 15-F2t-isoprostane from IEC-6 cells following OGD/R. The aforementioned effects of terlipressin were completely abolished following the application of 2 µM wortmannin. Therefore, the current study demonstrated that terlipressin administration following OGD attenuates OGD/R-induced cell damage via the PI3K signaling pathway. These results may help physicians to better understand and more effectively use terlipressin in a clinical setting.

Sevoflurane protects against hepatic ischemia/reperfusion injury by modulating microRNA-200c regulation in mice

This present study was aimed to investigate the molecular mechanisms involved in sevoflurane protection of hepatic ischemia-reperfusion (I/R) injury. Firstly, we investigated the protective effects of sevoflurane against hepatic I/R injury. Biochemical analysis results showed that sevoflurane preconditioning significantly protected against hepatic I/R injury by reducing liver enzymes and improving antioxidant defense markers. We also found that sevoflurane attenuates I/R-induced hepatic cell death, by TUNEL staining, DNA fragmentation ELISA and PARP activity determination. Next, In order to find the molecular mechanism of sevoflurane preconditioning in hepatic I/R injury, we poured our attention to microRNAs regulation. We focused on miR-200c, one of microRNAs which screened from the gene expression omnibus (GEO). Furthermore, a hydrogen peroxide (H₂O₂)-induced oxidative stress apoptosis model was also established to mimic hepatic I/R injury, the effects of MiR-200c was investigated. We observed that MiR-200c inhibition decreased the H₂O₂-induced apoptosis of hepatic AML-12 cells. And also, ZEB1 is found as a target gene of miR-200c and is involved in H₂O₂-induced apoptosis. On the other hand, the in vivo model was established to examine whether sevoflurane protect against hepatic IR injury by downregulating MiR-200c. Together with the biochemical tests and apoptosis detection, results showed that over-expression of miR-200c significantly inhibited the protect effect of sevoflurane in Hepatic IR injury. Summarizing, sevoflurane preconditioning seems to ameliorate hepatic I/R injury in mice, mediated by mechanisms that include microRNA 200c down regulation. However, further more studies need to be carried out to verify this point.

Quercetin attenuates cardiomyocyte apoptosis via inhibition of JNK and p38 mitogen-activated protein kinase signaling pathways

Quercetin (Que), a plant-derived flavonoid, possesses various biological functions. Moreover, Que exerts multiple beneficial actions in treatment of cardiovascular diseases and there are an inverse association between Que intakes and occurrence and development of various cardiovascular diseases. Some researchers have inferred that the mechanisms of Que to protect cardiomyocytes from ischemia/reperfusion (I/R) injury may be involved in modulation of intracellular signal pathways and regulation of proteins expression in vivo. The current study investigated whether Que has any protective effects on cardiomyocytes from hypoxia/reoxygenation (H/R) in vitro and its potential cardioprotective mechanisms. The cell viability of Que on H9c2 cardiomyoblast cells was assessed by MTT. Apoptosis was evaluated by both Hoechst33342 staining and Flow cytometric analysis (FACS). Furthermore, the effect of Que, SP600125 (JNK inhibitor) and SB203580 (p38 inhibitor) on mitogen-activated protein kinases (MAPKs) and the expression of apoptosis related proteins (Bcl-2, Bax and caspase-3) was determined by Western blotting. MTT assays showed that pretreatment with Que could increase the viability of H9c2 cardiomyocytes that suffered H/R. Both Hoechst33342 staining and FACS confirmed that Que could remarkably suppress the H/R-induced apoptotic cardiomyocytes. In addition, Que significantly alleviated H/R-induced the phosphorylation of JNK and p38, which further increased Bcl-2 expression and inhibited the activation of Bax and caspase-3 directly or indirectly. In summary, our results imply that Que can induce cardioprotection by inhibition of JNK and p38 mitogen-activated protein kinase signaling pathways and modulate the expression of Bcl-2 and Bax proteins that provides a new experimental foundation for myocardial ischemia disease therapy.