A quasi-experimental study of fresh oxygen flow on patients' oxygen reserve during mask-assisted ventilation under general anesthesia induction.

Background: To compare the effect of different amounts of fresh oxygen flow on oxygen reserve in patients undergoing general anesthesia. Methods: Seventy-two patients were enrolled in this quasi-experimental study. Patients were randomly divided into experimental groups with a fresh oxygen flow of 1 L/min, 2 L/min, 4 L/min, and 8 L/min (denoted as G1, G2, G3, and G4, respectively) for 2 min of mask-assisted ventilation. Safe apnea time (SAT) was the primary endpoint; SAT was defined as the time from the cessation of ventilation to the time the patient's pulse oxygen saturation (SpO2) decreased to 90%. Ventilation indicators such as end-tidal oxygen concentration (EtO2), end-tidal carbon dioxide partial pressure (EtCO2), SpO2, and carbon dioxide (CO2) elimination amount, during mask-assisted ventilation, were the secondary endpoints. Results: The SAT of G1, G2, G3, and G4 were 305.1 ± 97.0 s, 315 ± 112.5 s, 381.3 ± 118.6 s, and 359 ± 104.4 s, respectively (p > 0.05). The EtO2 after 2 min of mask-assisted ventilation in groups G1, G2, G3, and G4 were 69.7 ± 8.8%, 75.2 ± 5.0%, 82.5 ± 3.3%, and 86.8 ± 1.5%, respectively (p < 0.05). Also, there was a moderate positive correlation between the fresh oxygen flow and EtO2 (correlation coefficient r = 0.52, 95% CI 0.31-0.67, p < 0.0001). The CO2 elimination in the G1 and G2 groups was greater than that in the G4 group (p < 0.05). There was no significant difference in other indicators among the groups (all p > 0.05). Conclusion: The amount of fresh oxygen flow during mask-assisted ventilation was positively correlated with EtO2. Also, even though there was no significant difference, the patients' oxygen reserves increased with the increase in fresh oxygen flow.

Trastuzumab-induced human cardiomyocyte damage through the Notch2/JAK2/STAT3 pathway.

OBJECTIVE: Trastuzumab is the preferred drug for the treatment of breast cancer. However, research on the cellular mechanisms of trastuzumab's potential cardiotoxicity is insufficient. The purpose of this study was to explore the toxic effects and potential mechanism of action of trastuzumab on cardiomyocytes. METHOD: Human Cardiomyocyte (HCM) viability was assessed using the MTT method. HCM apoptosis was detected using the Hoechst33342/PI Fluorescent staining. The LDH and CK activities of the cell were measured using commercially available LDH and CK assay kits. The expression levels of Notch2, JAK2, STAT3, cleaved caspase 3, bax, and bcl 2 in HCMs were detected using western blotting. RESULTS: The results showed that 250 mg/L trastuzumab induced cardiomyocyte injury and apoptosis, inhibited viability, activated the Notch2 receptor, and inhibited JAK2/STAT3 expression in HCM. Inhibition of Notch2 expression in HCM by targeted siNotch2 transfection reversed the trastuzumab-induced injury and apoptosis, and the expression of JAK2/STAT3 returned to normal levels. CONCLUSIONS: Trastuzumab induces Notch2 expression by inhibiting the JAK2/STAT3 pathway of HCMs, promotes cell apoptosis, and causes cardiomyocyteinjury. Notch2 may be a potential target of trastuzumab-inducedmyocardial injury. This experiment reveals the mechanism of trastuzumab-induced cardiotoxicity, providing a theoretical basis for the application of trastuzumab.

Incidence rate of hypokalemic and its associated factors for patients undergoing noncardiac surgery: a retrospective analysis.

Background: Hypokalemia is common in hospitalized patients. In fact, untreated hypokalemia is associated with the incidence and mortality of adverse cardiac events. Timely recognition and treatment of these diseases are essential. Indeed, a little research has been conducted on the level of K+ in perioperative patients. In this study, by comparing the changes of K+ from when patients were admitted to hospital and to after they had entered the operating room, we analyzed the related factors of K+ disorder after operating-room entry and identified factors related to the occurrence of perioperative K+ disorder. Methods: This single-center retrospective study included non-cardiac surgery patients who underwent admission blood gas analysis and blood gas analysis upon entering the operating room in the China-Japan Union Hospital of Jilin University between June 2019 and September 2020. Results: Among the 258 patients who underwent non-cardiac surgery with anesthesia, 19 cases (7.4%) were hypokalemic on admission, and 102 cases (39.5%) were hypokalemic after admission to the operating room. The K+ levels after operating-room entry were positively correlated with the K+ concentration at admission (r=0.363; P<0.05). Female sex [odds ratio (OR) =0.451; 95% CI: 0.263-0.775; P=0.004], hypertension (OR =0.499; 95% CI: 0.281-0.885; P=0.017), and preoperative bowel preparation (OR =0.471; 95% CI: 0.258-0.860; P=0.014) were risk factors for hypokalemia for patients after operating-room entry. Conclusions: Hypokalemia was found to be common in patients after operating-room entry. Even patients with normal K+ at admission could have hypokalemia due to undergoing an operation, with female sex, hypertension, and bowel preparation being the risk factors for this condition.

Trastuzumab-induced human cardiomyocyte damage through the Notch2/JAK2/STAT3 pathway

Abstract Objective Trastuzumab is the preferred drug for the treatment of breast cancer. However, research on the cellular mechanisms of trastuzumab's potential cardiotoxicity is insufficient. The purpose of this study was to explore the toxic effects and potential mechanism of action of trastuzumab on cardiomyocytes. Method Human Cardiomyocyte (HCM) viability was assessed using the MTT method. HCM apoptosis was detected using the Hoechst33342/PI Fluorescent staining. The LDH and CK activities of the cell were measured using commercially available LDH and CK assay kits. The expression levels of Notch2, JAK2, STAT3, cleaved caspase 3, bax, and bcl 2 in HCMs were detected using western blotting. Results The results showed that 250 mg/L trastuzumab induced cardiomyocyte injury and apoptosis, inhibited viability, activated the Notch2 receptor, and inhibited JAK2/STAT3 expression in HCM. Inhibition of Notch2 expression in HCM by targeted siNotch2 transfection reversed the trastuzumab-induced injury and apoptosis, and the expression of JAK2/STAT3 returned to normal levels. Conclusions Trastuzumab induces Notch2 expression by inhibiting the JAK2/STAT3 pathway of HCMs, promotes cell apoptosis, and causes cardiomyocyteinjury. Notch2 may be a potential target of trastuzumab-inducedmyocardial injury. This experiment reveals the mechanism of trastuzumab-induced cardiotoxicity, providing a theoretical basis for the application of trastuzumab.

Comparison of the effectiveness of high-flow nasal oxygen vs. standard facemask oxygenation for pre- and apneic oxygenation during anesthesia induction: a systematic review and meta-analysis.

BACKGROUND: In recent years, high flow nasal oxygen (HFNO) has been widely used in clinic, especially in perioperative period. Many studies have discussed the role of HFNO in pre- and apneic oxygenation, but their results are controversial. Our study aimed to examine the effectiveness of HFNO in pre- and apneic oxygenation by a meta-analysis of RCTs. METHODS: EMBASE, PUBMED, and COCHRANE LIBRARY databases were searched from inception to July 2021 for relevant randomized controlled trails (RCTs) on the effectiveness of HFNO versus standard facemask ventilation (FMV) in pre- and apenic oxygenation. Studies involving one of the following six indicators: (1) Arterial oxygen partial pressure (PaO2), (2) End expiratory oxygen concentration (EtO2), (3) Safe apnoea time, (4) Minimum pulse oxygen saturation (SpO2min), (5) Oxygenation (O2) desaturation, (6) End expiratory carbon dioxide (EtCO2) or Arterial carbon dioxide partial pressure(PaCO2) were included. Due to the source of clinical heterogeneity in the observed indicators in this study, we adopt random-effects model for analysis, and express it as the mean difference (MD) or risk ratio (RR) with a confidence interval of 95% (95%CI). We conducted a risk assessment of bias for eligible studies and assessed the overall quality of evidence for each outcome. RESULTS: Fourteen RCTs and 1012 participants were finally included. We found the PaO2 was higher in HFNO group than FMV group with a MD (95% CI) of 57.38 mmHg (25.65 to 89.10; p = 0.0004) after preoxygenation and the safe apnoea time was significantly longer with a MD (95% CI) of 86.93 s (44.35 to 129.51; p < 0.0001) during anesthesia induction. There were no significant statistical difference in the minimum SpO2, CO2 accumulation, EtO2 and O2 desaturation rate during anesthesia induction between the two groups. CONCLUSIONS: This systematic review and meta-analysis suggests that HFNO should be considered as an oxygenation tool for patients during anesthesia induction. Compared with FMV, continuous use of HFNO during anesthesia induction can significantly improve oxygenation and prolong safe apnoea time in surgical patients.

Impact of 30° Reserve Trendelenburg Position on Lung Function in Morbidly Obese Patients Undergoing Laparoscopic Sleeve Gastrectomy.

Background: This study aimed to evaluate the impact of patients' positioning before and after intubation with mechanical ventilation, and after extubation on the lung function and blood oxygenation of patients with morbid obesity, who had a laparoscopic sleeve gastrectomy. Methods: Patients with morbid obesity (BMI ≥ 30 kg/m2, ASA I - II grade) who underwent laparoscopic sleeve gastrectomy at our hospital from June 2018 to January 2019 were enrolled in this prospective study. Before intubation, after intubation with mechanical ventilation, and after extubation, arterial blood was collected for blood oxygenation and gas analysis after posturing the patients at supine position or 30° reverse Trendelenburg position (30°-RTP). Results: A total of 15 patients with morbid obesity were enrolled in this self-compared study. Pulmonary shunt (Qs/Qt) after extubation was significantly lower at 30°-RTP (18.82 ± 3.60%) compared to that at supine position (17.13 ± 3.10%, p < 0.01). Patients' static lung compliance (Cstat), during mechanical ventilation, was significantly improved at 30°-RTP (36.8 ± 6.7) compared to that of those in a supine position (33.8 ± 7.3, p < 0.05). The PaO2 and oxygen index (OI) before and after intubation with mechanical ventilation were significantly higher at 30°-RTP compared to that at supine position, and in contrast, the PA-aO2 before and after intubation with mechanical ventilation was significantly reduced at 30°-RTP compared to that at supine position. Conclusion: During and after laparoscopic sleeve gastrectomy, patients with morbid obesity had improved lung function, reduced pulmonary shunt, reduced PA-aO2 difference, and increased PaO2 and oxygen index at 30°-RTP compared to that supine position.

Serious bronchospasm induced by cisatracurium besylate: A case report.

RATIONALE: Cis-atracurium as an intermediate-acting non-depolarizing neuromuscular blocker is widely used clinically with less causing cyclic fluctuations and less histamine release. As the use rate increases, allergic reactions and anaphylactoid reactions caused by cis-atracurium increase. PATIENT CONCERNS: A 23-year-old woman underwent laparoscopic bariatric surgery. Airway spasm occurred after anesthesia induction and the operation was suspended. After adjustment, the anesthesia was performed with the same anesthetic scheme again. After induction, skin flushing and airway resistance increased, then the symptoms were relieved. When the cis-atracurium was given again, the symptoms of airway spasm reappeared immediately, and after communicating with the family, the operation was successfully completed with rocuronium. DIAGNOSES: Serious bronchospasm induced by cisatracurium besylate. INTERVENTIONS: The patient was undergone assisted ventilation with continuous positive airway pressure (CPAP) and aminophylline 250 mg, methylprednisolone 80 mg were given intravenously. OUTCOMES: There was no any obvious discomfort in the patient's self-report during the next day's visit. The patient was discharged 7 days later. No abnormalities were observed during following 4 weeks. LESSONS: Although the anaphylactoid reactions caused by cis-atracurium are rare, the bronchospasm and anaphylactic shock caused by it greatly increase the risk of anesthesia, which should be taken seriously by clinicians. Increased vigilance in diagnosis, and treatment are essential to prevent aggravation and further complication.

Stabilization of the histone acetyltransferase Tip60 by deubiquitinating enzyme USP7 stimulates the release of pro-inflammatory mediators in acute lung injury.

Acute lung injury (ALI) is often associated with inflammation. Increasing evidence has identified the role for ubiquitin-specific protease 7 (USP7) in activating the expression of inflammatory factors in macrophages. The present study evaluated whether USP7 also mediates histone acetyltransferase Tat-interactive protein 60 (Tip60) in the development of ALI inflammation. An ALI mouse model was induced by intratracheal lipopolysaccharide (LPS) administration. Next, lung myeloperoxidase (MPO) activity and the ratio of dry weight/wet weight of lung were examined to evaluate tissue damage. In addition, RAW 264.7 cells were treated with LPS to induce an in vitro LPS-induced inflammatory cell model. ELISA was performed to measure expression of IL-1ß, TNF-α, IL-6, and IL-8 in cells and tissues. TUNEL was used to detect LPS-induced cell apoptosis. Furthermore, the interaction between USP7 and Tip60 was identified by IP, Western blot analysis, and cycloheximide (CHX) treatment. The enrichment of Tip60 and H3K27ac in the promoter region of IL-6 and IL-8 was assessed by ChIP. USP7 was highly expressed in LPS-endotoxin-induced ALI mouse models and silencing of USP7 delayed the progression of ALI in mice. Silencing of USP7 protected RAW 264.7 cells against LPS-induced inflammation and apoptosis by downregulating IL-1ß, TNF-α, IL-6, and IL-8. USP7 enhanced Tip60 protein stability, and Tip60 increased the enrichment of H3K27ac on IL-6 and IL-8 promoter region and activated NF-κB p65 to increase IL-6 and IL-8 expression. These findings reveal a new post-transcriptional role for USP7 in inflammation by stabilizing Tip60 and increasing the release of the pro-inflammatory cytokines, and implicate USP7 inhibitors as potential therapeutic agents for ALI. KEY MESSAGES: USP7 expresses highly in an acute lung injury (ALI) mouse models. Silencing of USP7 inhibits inflammation and cell apoptosis in ALI mouse. USP7 stabilizes Tip60 to boost the release of IL-6 and IL-8. Tip60 increases IL-6 and IL-8 expression by acetylating NF-κB p65. Silencing of USP7 alleviates ALI by repressing NF-κB p65 and Tip60.

Catastrophic thoracolumbar spinal massive hematoma triggered by intraspinal anesthesia puncture: A CARE-compliant case report.

RATIONALE: Intraspinal anesthesia, the most common anesthesia type of orthopedic operation, is regarded as safe and simple. Despite of the rare incidence, puncture related complication of intraspinal anesthesia is catastrophic for spinal cord. Here we present an intradural hematoma case triggered by improper anesthesia puncture. The principal reason of this tragedy was rooted in the neglect of spine deformities diagnosis before anesthesia. To the best of our knowledge, there is no specific case report focusing on the intradural hematoma triggered by improper anesthesia puncture. PATIENT CONCERNS: Hereby a case of thoracolumbar spinal massive hematoma triggered by intraspinal anesthesia puncture was reported. The presenting complaint of the patient was little neurologic function improvement after surgery at 6-month follow-up. DIAGNOSES: Emergency MRI demonstrated that massive spindle-like intradural T2-weighted image hypointense signal masses from T12 to S2 badly compressed the dural sac ventrally, and his conus medullaris was at L3/4 intervertebral level with absence of L5 vertebral lamina. Hereby, the diagnoses were congenital spinal bifida, tethered cord syndrome, spine intradural hematoma, and paraplegia. INTERVENTIONS: Urgent surgical interventions including laminectomy, spinal canal exploration hematoma removal, and pedicle fixation were performed. The patient received both medication (mannitol, mecobalamin, and steroids) and rehabilitation (neuromuscular electric stimulation, hyperbaric oxygen). OUTCOMES: Postoperation, he had regained only hip and knee flexion at II grade strength. His neurologic function was unchanged until 3 weeks postoperation. Six-month follow-up showed just little neurologic function improvement, and the American Spinal Injury Association grade was C. LESSONS: By presenting an intradural hematoma case triggered by improper anesthesia puncture, we shared the treatment experience and discussed the potential mechanism of neurologic compromise. The principal reason for this tragedy is preanesthesia examination deficiency. Necessary radiology examinations must be performed to prevent misdiagnosis for spinal malformation.

Propofol Target-controlled Infusion in Anesthesia Induction during Painless Gastroscopy.

OBJECTIVE: To investigate the feasibility of using the eyelash reflex as an indicator to calculate the individualised optimal target concentration in anesthesia induction during painless gastroscopy. STUDY DESIGN: Experimental study. PLACE AND DURATION OF STUDY: China-Japan Union Hospital of Jilin University, China, from January to December in 2016. METHODOLOGY: A total of 180 patients, who were scheduled to receive painless fibergastroscopic examination or treatment in the last three months, were enrolled in this study. All patients were randomly divided into three groups, according to the doctor visiting order (n=60, each). During the induction of anesthesia using propofol target-controlled infusion, the effectsite concentration upon the disappearance of the eyelash reflex (C0) was recorded first. Then, one ug/kg of fentanyl was injected. At the same time, the target effect-site concentration induced by propofol was determined: the effect-site concentration in group A was 1.5 times of C0, the effect-site concentration in group B was two times of C0, and the effectsite concentration in group C was 2.5 times of C0. RESULTS: During anesthesia induction, the incidence of motor responses was higher in group A than in groups B and C (p<0.05), and the incidence of hypoxemia was significantly higher in group C than in groups A and B (p<0.01). CONCLUSION: In the anesthesia option of fentanyl combined with propofol target-controlled infusion, the effect-site concentration of propofol can be set to two times of that at the time the eyelash reflex disappears. This study provides a new pre-assessment method for the induction dose of propofol in painless gastroscopy.

Negative pressure pulmonary edema after general anesthesia: A case report and literature review.

RATIONALE: Negative pressure pulmonary edema (NPPE) is a dangerous clinical complication and potentially life-threatening emergency without prompt diagnosis and intervention during recovery period after anesthetic extubation. PATIENT CONCERNS: A 25-year-old woman has undergone endoscopic thyroidectomy. After extubation, the patient developed acute respiratory distress with high airway resistance accompanied with wheezing, oxyhemoglobin saturation (SpO2) decreased to 70%. With positive pressure mask ventilation, her condition was stable, SpO2 99%. However, the patient developed pink frothy sputum with diffuse bilateral rales 30 min later after transported to surgical intensive care unit (SICU). DIAGNOSES: Negative pressure pulmonary edema. INTERVENTIONS: The patient was undergone assisted ventilation with continuous positive airway pressure (CPAP) and furosemide 20 mg was given intravenously. OUTCOMES: Postoperative day (POD) 2 her condition became stable, computed tomography (CT) scan indicated the pulmonary edema disappeared. The patient was discharged 6 days later. No abnormalities were observed during following 4 weeks. LESSONS: Although usually the onset of NPPE is rapid, with individual differences NPPE is still challenging. Increased vigilance in monitoring, diagnosis, and treatment are essential to prevent aggravation and further complication.

Prophylactic treatment with MSC-derived exosomes attenuates traumatic acute lung injury in rats.

The mesenchymal stem cell (MSC) is a potential strategy in the pretreatment of traumatic acute lung injury (ALI), a disease that causes inflammation and oxidative stress. This study aimed to investigate whether MSC-exosomal microRNA-124-3p (miR-124-3p) affects traumatic ALI. Initially, a traumatic ALI rat model was established using the weight-drop method. Then, exosomes were obtained from MSCs of Sprague-Dawley rats, which were injected into the traumatic ALI rats. We found that miR-124-3p was abundantly-expressed in MSCs-derived exosomes and could directly target purinergic receptor P2X ligand-gated ion channel 7 (P2X7), which was overexpressed in traumatic ALI rats. After that, a loss- and gain-of-function study was performed in MSCs and traumatic ALI rats to investigate the role of miR-124-3p and P2X7 in traumatic ALI. MSC-derived exosomal miR-124-3p or silenced P2X7 was observed to increase the survival rate of traumatic ALI rats and enhance the glutathione/superoxide dismutase activity in their lung tissues. However, the wet/dry weight of lung tissues, activity of methylenedioxyamphetamine and H2O2, and levels of inflammatory factors (TNF-a, IL-6, and IL-8) were reduced. Similarly, the numbers of total cells, macrophages, neutrophils, and lymphocytes in bronchoalveolar lavage fluid were also reduced when treated with exosomal miR-124-3p or silenced P2X7. In conclusion, the results provide evidence that miR-124-3p transferred by MSC-derived exosomes inhibited P2X7 expression, thus improving oxidative stress injury and suppressing inflammatory response in traumatic ALI, highlighting a potential pretreatment for traumatic ALI.

Neuroinflammation and central PI3K/Akt/mTOR signal pathway contribute to bone cancer pain.

BACKGROUND: Pain is one of the most common and distressing symptoms suffered by patients with progression of cancer; however, the mechanisms responsible for hyperalgesia are not well understood. Since the midbrain periaqueductal gray is an important component of the descending inhibitory pathway controlling on central pain transmission, in this study, we examined the role for pro-inflammatory cytokines of the periaqueductal gray in regulating mechanical and thermal hyperalgesia evoked by bone cancer via phosphatidylinositide 3-kinase (PI3K)-mammalian target of rapamycin (mTOR) signals. METHODS: Breast sarcocarcinoma Walker 256 cells were implanted into the tibia bone cavity of rats to induce mechanical and thermal hyperalgesia. Western blot analysis and ELISA were used to examine PI3K/protein kinase B (Akt)/mTOR and pro-inflammatory cytokine receptors and the levels of interleukin (IL)-1ß, IL-6, and tumor necrosis factor-alpha (TNF-α). RESULTS: Protein expression levels of p-PI3K/p-Akt/p-mTOR were amplified in the periaqueductal gray of bone cancer rats, and blocking PI3K-mTOR pathways in the periaqueductal gray attenuated hyperalgesia responses. In addition, IL-1ß, IL-6, and TNF-α were elevated in the periaqueductal gray of bone cancer rats, and expression of their respective receptors (namely, IL-1R, IL-6R, and tumor necrosis factor receptor (TNFR) subtype TNFR1) was upregulated. Inhibition of IL-1R, IL-6R, and TNFR1 alleviated mechanical and thermal hyperalgesia in bone cancer rats, accompanied with downregulated PI3K-mTOR. CONCLUSIONS: Our data suggest that upregulation of pro-inflammatory cytokine signal in the periaqueductal gray of cancer rats amplifies PI3K-mTOR signal in this brain region and alters the descending pathways in regulating pain transmission, and this thereby contributes to the development of bone cancer-induced pain.

Endotracheal catheter equipped with functional cuff produces clinically relevant positive end expiratory pressure: a bench study.

Recently, we developed a novel endotracheal catheter with functional cuff (ECFC). Using such an ECFC and a regular ICU ventilator, we were able to generate clinically relevant tidal volume in a lung model and adult human sized animal. This ECFC allows co-axial ventilation without using a jet ventilator. The aim of this study was to determine if ECFC also could generate clinically relevant positive end expiratory pressure (PEEP). The experiment was conducted on a model lung and artificial trachea. Lung model respiratory mechanics were set to simulate those of an adult human being. The tip of the distal end of ECFC 14 or 19 Fr catheter was positioned in the artificial trachea 3 cm above the carina. The proximal end of ECFC was connected to an ordinary ICU ventilator. With 14 Fr catheter at respiratory rate 10 bpm, PEEP 0, 2.9, 8.2, 12.9 cmH2O was generated at preset PEEP 0, 5, 10, 15 cmH2O respectively and tidal volume was up to 393.4 ml. With 19 Fr catheter, PEEP was 0, 2.8, 7.6, 12.3 cmH2O, at preset PEEP 0, 5, 10, 15 cmH2O respectively and the tidal volume was up to 667.3 ml. With 14 Fr catheter at respiratory rate 20 bpm, PEEP was 0, 3.9, 9.6, 14.6 cmH2O at preset PEEP 0, 5, 10, 15 cmH2O respectively and tidal volume was up to 188.8 ml. With 19 Fr catheter, PEEP was 0, 3.6, 8.9, 13 cmH2O, at preset PEEP 0, 5, 10, 15 cmH2O respectively and tidal volume was up to 345.3 ml. ECFC enables clinicians to generate not only adequate tidal volume but also clinically relevant PEEP via co-axial ventilation using an ordinary ICU ventilator.

MicroRNA-485 Modulates the TGF-ß/ Smads Signaling Pathway in Chronic Asthmatic Mice by Targeting Smurf2.

BACKGROUND/AIMS: Chronic respiratory conditions continue to plague millions of people worldwide. We aimed to elucidate the detailed mechanisms of microRNA-485 (miR-485) in airway smooth muscle cell (ASMC) proliferation and apoptosis in chronic asthmatic mice. METHODS: A mouse model of chronic asthma was established. Ovalbumin was used to induce chronic asthma in the mice. The levels of transforming growth factor ß (TGF-ß), interleukin (IL)-4, IL-5, IL-13 and IL-17 in bronchoalveolar lavage fluid in mice were measured by enzyme-linked immunoassays (ELISAs). ASMCs were transfected with miR-485 mimic, miR-485 inhibitor and siRNA-Smurf2. The reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blot analyses were applied to detect the mRNA and protein levels of Smurf2, α-SMA, TGF-ß1 and decapentaplegic homolog (Smads). The MTT assay was utilized for cell proliferation, while flow cytometry was conducted to assess cell cycle distribution and apoptosis. RESULTS: Lower expression of miR-485 and higher expression levels of TGF-ß1, IL-4, IL-5, IL-13 and IL-17 were detected in mice with chronic asthma. Smurf2 was identified as the target gene of miR-485. Upregulation of miR-485 mimic and downregulation of Smurf2 decreased expression levels of Smurf2, α-SMA, TGF-ß1 and Smad3, inhibited cell proliferation and increased apoptosis, while contrary results were observed in ASMCs transfected with miR-485 inhibitor. CONCLUSION: Overexpressed miR-485 inhibits cell proliferation and promotes apoptosis of ASMCs through the Smurf2-mediated TGF-ß/Smads signaling pathway in mice with chronic asthma.

Long noncoding RNA SNHG16 reduced ketamine-induced neurotoxicity in human embryonic stem cell-derived neurons.

BACKGROUND: Clinical evidence demonstrates that prolonged exposure to ketamine may cause irreversible injury to immature human brains. In this study, we utilized an in vitro model to examine the function of long noncoding RNA (lncRNA) SNHG16 in ketamine-induced neurotoxicity in human embryonic stem cell (hESC)-derived neurons. METHODS: HESCs were induced toward neuronsin vitro, and treated with ketamine, at various concentrations, for 48 h. Viability, apoptosis, caspase-3 activity and ROS activity were then examined among hESC-derived neurons. Ketamine-induced gene expression change of SNHG16 was assessed by qRT-PCR. SNHG16 was overexpressed in hESC-derived neurons, which were then treated with ketamine, followed by biochemical assays to assess the effects of SNHG16 upregulation on ketamine-induced neurotoxicity. Correlation between SNHG16 and NeuroD1 gene was assess by qRT-PCR. In SNHG16-upregulated hESC-derived neurons, they were double transfected with siRNA to knock down NeuroD1. The functions of NeuroD1 inhibition on SNHG16-associated neural protection on ketamine-induced neurotoxicity were further assessed. RESULTS: 48-h in vitro treatment of ketamine induced significant neurotoxicity, and downregulated SNHG16 among hESC-derived neurons. Conversely, SNHG16 upregulation reduced ketamine-induced neurotoxicity. NeuroD1 expression was downregulated by ketamine in hESC-derived neurons, and concomitantly upregulated by SNHG16 overexpression. SiRNA-mediated NeuroD1 inhibition reversed the protection of SNHG16 upregulation on ketamine-induced neurotoxicity. CONCLUSIONS: SNHG16 is an important epigenetic factor which may functionally modulate ketamine-induced neurotoxicity through NeuroD1.

Blocking Mammalian Target of Rapamycin (mTOR) Alleviates Neuropathic Pain Induced by Chemotherapeutic Bortezomib.

BACKGROUND/AIMS: Bortezomib (BTZ) is largely used as a chemotherapeutic agent for the treatment of cancer. However, one of the significant limiting complications of BTZ is painful peripheral neuropathy during BTZ therapy. Drugs preventing and/or treating the painful symptoms induced by BTZ are lacking since the underlying mechanisms leading to neuropathic pain remain largely unclear. The purposes of this study were to examine 1) the effects of blocking mammalian target of rapamycin (mTOR) on mechanical pain and cold hypersensitivity evoked by BTZ and 2) the underlying mechanisms responsible for the role of mTOR in regulating BTZ-induced neuropathic pain. METHODS: Behavioral test was performed to determine mechanical pain and cold sensitivity in a rat model. Western blot analysis and ELISA were used to examine expression of mTOR and phosphatidylinositide 3-kinase (p-PI3K) signals, and the levels of substance P and calcitonin gene-related peptide (CGRP). RESULTS: Systemic injection of BTZ significantly increased mechanical pain and cold sensitivity as compared with control animals (P< 0.05 vs. control rats). The expression of p-mTOR, mTOR-mediated phosphorylation of p70 ribosomal S6 protein kinase 1 (p-S6K1), 4E-binding protein 4 (p-4E-BP1) as well as p-PI3K was amplified in the dorsal horn of spinal cord of BTZ rats as compared with control rats. Blocking mTOR by intrathecal infusion of rapamycin attenuated mechanical pain and cold hypersensitivity. Blocking PI3K signal also attenuated activities of mTOR, which was accompanied with decreasing neuropathic pain. Inhibition of either mTOR or PI3K blunted enhancement of the spinal substance P and CGRP in BTZ rats. CONCLUSIONS: The data for the first time revealed specific signaling pathways leading to BTZ-induced peripheral neuropathic pain, including the activation of mTOR and PI3K. Inhibition of these signal pathways alleviates pain. Targeting one or more of these signaling molecules may present new opportunities for treatment and management of peripheral painful neuropathy observed during chemotherapeutic application of BTZ.

MicroRNA-142 Inhibits Proliferation and Promotes Apoptosis in Airway Smooth Muscle Cells During Airway Remodeling in Asthmatic Rats via the Inhibition of TGF-ß -Dependent EGFR Signaling Pathway.

BACKGROUND/AIMS: Asthma is a heterogeneous disease characterized by chronic airway inflammation resulting from airway hyper-responsiveness to diverse stimuli. In this study, we investigated whether microRNA-142 (miR-142) expression affects proliferation and apoptosis in airway smooth muscle cells (ASMCs) during airway remodeling in asthmatic rats. METHODS: Thirty six Wistar rats were randomly classified into a control group and an model group. miR-142 mimics and inhibitors were constructed, and ASMCs were transfected using liposomes according to the following groups: blank, negative control (NC), miR-142 mimics, miR-142 inhibitors, si-TGF-ß and miR-142 inhibitors + si-TGF-ß. We verified that miR-142 targets TGF-ß using a dual-luciferase reporter assay. The expression levels of miR-142, TGF-ß, EGFR and apoptosis signaling pathway-related genes were determined using RT-qPCR and western blotting. Changes in cell proliferation, cell cycle progression and apoptosis were analyzed using MTT assays and flow cytometry. RESULTS: Rats with asthma had higher expression levels of EGFR and Akt and lower miR-142 levels. miR-142 was negatively correlated with TGF-ß expression. In ASMCs, the expression of TGF-ß, EGFR, Akt, phosphorylated-Akt (p-Akt), Bcl-2 and Bcl-xl and the rate of early apoptosis were decreased while expression of Bax and p21 and the proliferation rate were elevated with the upregulation of miR-142. The opposite results were observed with the downregulation of miR-142. Finally, the proliferative rate was decreased while the apoptosis rate was increased and expression levels of EGFR, Akt, p-Akt, Bcl-2 and Bcl-xl were reduced while Bax and p21 were elevated in the ASMCs transfected with miR-142 inhibitors and si-TGF-ß. CONCLUSION: The results of our study suggest that miR-142 inhibits proliferation and promotes apoptosis in ASMCs during airway remodeling in asthmatic rats by inhibiting TGF-ß expression via a mechanism involving the EGFR signaling pathway.

Propofol elicits autophagy via endoplasmic reticulum stress and calcium exchange in C2C12 myoblast cell line.

In this study, we investigated the relationship between propofol and autophagy and examined whether this relationship depends on ER stress, production of ROS (reactive oxygen species), and disruption of calcium (Ca2+) homeostasis. To this end, we measured C2C12 cell apoptosis in vitro, along with Ca2+ levels; ROS production; and expression of proteins and genes associated with autophagy, Ca2+ homeostasis, and ER stress, including LC3 (microtubule-associate protein 1 light chain 3), p62, AMPK (adenosine 5'-monophosphate (AMP)-activated protein kinase), phosphorylated AMPK, mTOR (the mammalian target of rapamycin), phosphorylated mTOR, CHOP (C/BEP homologous protein), and Grp78/Bip (78 kDa glucose-regulated protein). We found that propofol treatment induced autophagy, ER stress, and Ca2+ release. The ratio of phosphorylated AMPK to AMPK increased, whereas the ratio of phosphorylated mTOR to mTOR decreased. Collectively, the data suggested that propofol induced autophagy in vitro through ER stress, resulting in elevated ROS and Ca2+. Additionally, co-administration of an ER stress inhibitor blunted the effect of propofol.