HSP90 Inhibition Attenuated Isoflurane-Induced Neurotoxicity in Mice and Human Neuroglioma Cells.

Isoflurane, a widely used inhalation anesthetic in clinical practice, is associated with an increased risk of neuronal injury. Heat shock protein 90 (HSP90) plays a crucial role in maintaining neuronal homeostasis under stress conditions; however, its role during isoflurane exposure remains poorly understood. In this study, we aimed to investigate the protective effects of HSP90 inhibition and explore the regulatory mechanisms underlying these effects during isoflurane exposure. We found that the HSP90 inhibitor 17-N-allylamino-17-demethoxygeldanamycin (17 AAG) has great protective effects in mitigating isoflurane-induced ferroptosis of mouse hippocampus and cultured neuronal cells. We focused on the activity of the crucial protein GPX4 in ferroptosis and found that 17 AAG exerted protective effects, preserving the physiological GPX4 activity under isoflurane exposure; further, 17 AAG restored the protein level of GPX4. Further, we observed that the chaperone-mediated autophagy (CMA) pathway was activated; 17 AAG also mediated GPX4 degradation under isoflurane exposure. Additionally, it interfered with the formation of complexes between HSP90 and Lamp-2a, inhibiting CMA activity, followed by the blockade of GPX4 degradation, further affecting the isoflurane-induced ferroptosis. Based on these findings, we proposed HSP90 inhibition as a protective mechanism against isoflurane-induced ferroptosis in neurons.

Comparison of primary keloid fibroblast cultivation methods and the characteristics of fibroblasts cultured from keloids, keloid-surrounding tissues, and normal skin tissues / Comparación de los métodos de cultivo de fibroblastos queloides primarios y las características de los fibroblastos cultivados a partir de queloides, tejidos circundantes queloides y tejidos cutáneos normales

SUMMARY: The establishment of primary keloid fibroblast culture has always been a fundamental measure for studying mechanisms of keloid disease. The quality of the primary cell culture can directly affect the results of further experiments. This study was performed to investigate the optimal growth conditions, including the optimal storage time and collagenase treatment time, for in vitro cell culture models and the suitable methods for epidermis-dermis separation in different tissues. Keloid tissues, keloid-surrounding tissues, and normal skin tissues were collected from patients, for primary fibroblast culture. Two methods, tissue explant and collagenase digestion, were deployed and compared. Expression levels of the keloid-related genes α -SMA, Col1, and Col3 were assessed in cells cultured using both methods, to verify the qualities of the primary cells. A comparative analysis was conducted between the two methods and among the three different tissues used. Bacterial and lipid contamination was immediately minimized after the samples were processed. Different methods of epidermis removal and different durations of collagenase digestion were required in different tissues to generate optimal results. Real-time PCR results showed that the mRNA expression levels of keloid-related genes in cultured fibroblasts correlated to their in vivo expression profile, as previously reported in other studies. The results of this study have revealed several key points in the culture of primary keloid fibroblasts and demonstrated the correlation in gene expression between in vivo keloid fibroblasts and in vitro primary keloid fibroblasts.

RESUMEN: La identificación de un cultivo de fibroblastos queloides primarios, siempre ha sido una medida fundamental para estudiar los mecanismos de la enfermedad queloide. La calidad del cultivo de células primarias puede afectar directamente los resultados de otros experimentos. Este estudio se realizó para investigar las condiciones óptimas de crecimiento, incluido el tiempo óptimo de almacenamiento y el tiempo de tratamiento con colagenasa, para modelos de cultivo celular in vitro y los métodos adecuados para la separación epidermis-dermis en diferentes tejidos. Se recogieron de los pacientes tejidos queloides, tejidos circundantes queloides y tejidos cutáneos normales, para cultivo primario de fibroblastos. Se implementaron y compararon dos métodos, explante de tejido y digestión con colagenasa. Los niveles de expresión de los genes relacionados con queloides α -SMA, Col1 y Col3 se evaluaron en células cultivadas usando ambos métodos, para verificar las cualidades de las células primarias. Se realizó un análisis comparativo entre los dos métodos y entre los tres tejidos diferentes utilizados. La contaminación de bacterias y lípidos se minimizó inmediatamente después de que se procesaron las muestras. Se requirieron varios métodos de eliminación de la epidermis y diferentes tiempos de digestión con colagenasa en los tejidos para generar resultados óptimos. Los resultados de la PCR en tiempo real mostraron que los niveles de expresión de ARNm de genes relacionados con queloides en fibroblastos cultivados se correlacionaban con su perfil de expresión in vivo, como se informó en estudios anteriores. Los resultados de este studio indicaron varios puntos clave en el cultivo de fibroblastos queloides primarios y han demostrado la correlación en la expresión génica entre fibroblastos queloides in vivo y fibroblastos queloides primarios in vitro.

Transversus abdominis plane block with general anesthesia blunts the perioperative stress response in patients undergoing radical gastrectomy.

BACKGROUND: Surgical stress induces the release of neuroendocrine mediators and cytokines during perioperative period, which may have adverse effects on cancer patients. While the surgical stress responsse can be affected by anesthetic technique. Therefore, we designed this study to assess whether subcostal transversus abdominis plane (TAP) block can affect perioperative neuroendocrine stress response, postoperative analgesia and postoperative recovery in patients undergoing radical gastrectomy under general anesthesia. METHODS: Sixty-five patients were recruited. Patients randomly received general anesthesia (control group), or general anesthesia combined with TAP block (40 mL of 0.375% ropivacaine) (TAP group). The primary outcome was neuroendocrine levels including norepinephrine (NE), epinephrine (E), cortisol (Cor), glucose (Glu), interleukin (IL)-6 and IL-10 during 48 h after surgery. Secondary outcomes included pain score, hemodynamic variables and recovery characteristics. RESULTS: Data from 61 of 65 patients were analyzed. The levels of NE, E, Cor, and Glu were blunt by TAP block during perioperative period. The levels of IL-6 and IL-10 were significantly lower in TAP group than in control group. TAP block efficiently relieved postoperative acute pain up to 12 h postoperatively with more stable perioperative hemodynamics compared with control group. CONCLUSIONS: Subcostal TAP block blunts perioperative stress response and provides efficient analgesia, with good hemodynamic stability and minimal adverse effects.

Beclin1-mediated ferroptosis activation is associated with isoflurane-induced toxicity in SH-SY5Y neuroblastoma cells.

The widely used inhalation anesthetic, isoflurane, potentially induces neuronal injury in clinical practice. Previous studies showed multiple forms of cell death that resulted from isoflurane-induced cytotoxicity, but the precise underlying mechanism remains poorly understood. Ferroptosis has recently been identified as a non-apoptotic form of regulated cell death. Here, we found that ferroptosis inhibitors, ferrostatin-1 and deferoxamine mesylate (DFOM), showed great efficiency in maintaining cell viability in SH-SY5Y neuroblastoma cells exposed to a high concentration of isoflurane for 24 h. We also observed that cellular chelatable iron and lipid peroxidation were increased in a concentration-dependent manner in response to isoflurane. In addition, isoflurane upregulated Beclin1 phosphorylation, followed by the formation of a Beclin1-solute carrier family 7 member 11 (SLC7A11) complex, which affected the activity of cystine/glutamate antipoter and further regulated ferroptotic cell death. Accordingly, Beclin1 overexpression aggravated isoflurane-induced cell damage by upregulating ferroptosis. This phenomenon was significantly attenuated by silencing of Beclin1 in SH-SY5Y cells. These findings indicate that Beclin1 may regulate ferroptosis in a manner involving inhibition of glutamate exchange activity of system xc(-), which is implicated in isoflurane-induced toxicity. In particular, when isoflurane is administrated at high concentrations and for an extended duration, ferroptosis is more likely to play a crucial role in isoflurane-induced toxicity.

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.

Efficacy of different analgesic or sedative drug therapies in pediatric patients with congenital heart disease undergoing surgery: a network meta-analysis.

BACKGROUND: Surgery is an effective therapy for congenital heart disease (CHD) and the management after surgery poses challenges for the clinical workers. We performed this network meta-analysis to enhance the corresponding evidence with respect to the relative efficacy of different drug treatments applied after the CHD surgery. METHODS: Embase and PubMed were systematically retrieved to identify all published controlled trials investigating the effectiveness of drugs for patients up to 25 August, 2018. Mean differences (MD), odds ratios and their 95% credible intervals (CrIs) were used to evaluate multi-aspect comparisons. Surface under cumulative ranking curve (SUCRA) was used to analyze the relative ranking of different treatments in each endpoint. RESULTS: Compared to saline, all the drugs achieved better preference under the efficacy endpoints except fentanyl in JET. As for ventilator time, all drugs were more effective than saline while only the difference of dexmedetomidine was statistically obvious (MD = 6.92, 95% CrIs 1.77-12.54). Under the endpoint of ICU time, dexmedetomidine was superior to saline as well (MD = 1.26, 95% CrIs 0.11-2.45). When all the endpoints were taken into consideration and with the help of ranking probabilities and SUCRA values, fentanyl combined with dexmedetomidine was one of the recommended drugs due to its shorter time on ventilator and stay in hospital as well as lower mortality. CONCLUSIONS: Overall, based on the comprehensive consideration of all the endpoints, fentanyl combined with dexmedetomidine was considered to be the best-recommended clinical interventions among all the methods.

Cytosolic HMGB1 Mediates Autophagy Activation in an Emulsified Isoflurane Anesthesia Cell Model.

Inhalation anesthetic isoflurane may cause an increased risk of cognitive impairment. Previous studies have indicated that this cognitive decline is associated with neuroinflammation mediated by high mobility group box 1 (HMGB1). HMGB1 is released from cells and acts as a damage-associated molecule in neurodegenerative diseases. However, the effect of intracellular HMGB1 during emulsified isoflurane (EI) exposure is poorly understood. The purpose of this study was to investigate the effect of autophagy on neuroprotection, evaluate variation of HMGB1, and determine its role in autophagic flux after EI exposure in vitro. We observed that EI decreased cell viability in a concentration-dependent manner, accompanied by an increase in autophagic flux. EI exposure also elevates the HMGB1 level in cytoplasm. Further, cytosolic HMGB1 was necessary for autophagy by perturbing the beclin1-Bcl-2 interaction. Most importantly, autophagy induction by rapamycin alleviated EI-provoked cell injury, and HMGB1 knockdown induced autophagy inhibition, which exacerbated cell damage. Based on these findings, we propose that autophagic flux is sustained and upregulated in response to EI exposure by increased cytosolic HMGB1, and that autophagy activation serves as a protective mechanism against EI-induced cytotoxicity. Thus, the complex roles of HMGB1 make it pivotal in reducing EI-induced neuronal damage.

Dysregulation and diagnostic potential of microRNA in Alzheimer's disease.

Alzheimer's disease (AD) is one of the most common neurodegenerative diseases and is considered to be the main cause of cognitive impairment in elderly people. The major symptom of AD is progressive dementia that eventually results in dysfunction of daily life. Due to the fact that AD has a long period of incubation before clinical symptoms emerge, the available therapeutic treatments can only improve the symptoms but not delay the progression of AD. Therefore, there is an urgent need to explore effective diagnostic approaches to catch and better treat the disease before clinical symptoms appear. Recent research revealed that abnormal expression of certain miRNA could have a crucial role in the pathological process of neurodegenerative disease including AD. Furthermore, given that AD patients show increased level of miRNAs in the blood and cerebrospinal fluid, miRNAs are considered promising non-invasive candidates for AD diagnosis and prognosis. Here, we reviewed the current research related to implications of miRNAs during the development of AD, summarized of actively used approaches to identifying potential miRNA biomarkers in body fluids, and discussed the diagnostic potential of microRNAs as biomarkers for AD.