The Role of P53 in Myocardial Ischemia-Reperfusion Injury.

PURPOSE: P53 is one of the key tumor suppressors. In normal cells, p53 is maintained at low levels by the ubiquitination of the ubiquitinated ligase MDM2. In contrast, under stress conditions such as DNA damage and ischemia, the interaction between p53 and MDM2 is blocked and activated by phosphorylation and acetylation, thereby mediating the trans-activation of p53 through its target genes to regulate a variety of cellular responses. Previous studies have shown that the expression of p53 is negligible in normal myocardium, tends to increase in myocardial ischemia and is maximally induced in ischemia-reperfused myocardium, demonstrating a possible key role of p53 in the development of MIRI. In this review, we detail and summarize recent studies on the mechanism of action of p53 in MIRI and describe the therapeutic agents targeting the relevant targets to provide new strategies for the prevention and treatment of MIRI. METHODS: We collected 161 relevant papers mainly from Pubmed and Web of Science (search terms "p53" and "myocardial ischemia-reperfusion injury"). After that, we selected pathway studies related to p53 and classified them according to their contents. We eventually analyzed and summarized them. RESULTS AND CONCLUSION: In this review, we detail and summarize recent studies on the mechanism of action of p53 in MIRI and validate its status as an important intermediate affecting MIRI. On the one hand, p53 is regulated and modified by multiple factors, especially non-coding RNAs; on the other hand, p53 regulates apoptosis, programmed necrosis, autophagy, iron death and oxidative stress in MIRI through multiple pathways. More importantly, several studies have reported medications targeting p53-related therapeutic targets. These medications are expected to be effective options for the alleviation of MIRI, but further safety and clinical studies are needed to convert them into clinical applications.

Intravenous Administration of Hypertonic Glucose Solution to Prevent Dizziness in Patients Undergoing Gastrointestinal Endoscopy Under General Anesthesia: A Randomized Clinical Trial.

BACKGROUND AND OBJECTIVE: Dizziness is a common complication of gastrointestinal endoscopy under general anesthesia. Dizziness is primarily caused by a lack of energy and blood volume following fasting and water deprivation. Hypertonic glucose solution (HGS) is an intravenous energy replenishment, that increases blood volume due to its hyperosmotic characteristics and can be directly absorbed from blood circulation. This study aimed to HGS can prevent dizziness after gastrointestinal endoscopy. METHODS: This was a double-blind, randomized, controlled study. Eligible patients were randomly allocated into two groups based on the intravenous agent administered before gastrointestinal endoscopy: Group A, saline (0.9%; 20 mL); and group B, HGS (50%; 20 mL). Overall, 840 patients were included in the statistical analysis. The scores and incidence of dizziness were assessed. RESULTS: The dizziness score were higher in group A than in group B (1.92 ± 0.08 vs. 0.92 ± 0.06; p < 0.01). The incidence of mild dizziness and moderate-to-severe dizziness was significantly lower in group B than in group A (40.10% vs. 51.78% and 3.10% vs. 19.72%, respectively; p < 0.01). The incidence and score of dizziness were significantly lower in males than in females (30.81% vs. 51.82% and 0.64 ± 0.08 vs. 1.12 ± 0.08, respectively; p < 0.01) after pretreatment with HGS. CONCLUSION: Pretreatment with HGS effectively prevents dizziness after gastrointestinal endoscopy under general anesthesia. The mechanism of action is unclear but might be related to body energy replacement and an increase in blood volume following HGS administration.

TRAF3IP3 promotes glioma progression through the ERK signaling pathway.

TRAF3IP3 was reportedly associated with poor prognosis in patients with melanoma; however, its role in glioma is unknown. We aimed to demonstrate the relationship between TRAF3IP3 and glioma and to investigate the potential role of TRAF3IP3 in glioma. Datasets were collected from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. We used the Wilcoxon rank-sum test to compared TRAF3IP3 expression in normal and glioma tissues. Kaplan-Meier analysis was performed to evaluate the correlation between TRAF3IP3 and patient survival rate. Gene set enrichment analysis (GSEA) was used to annotate the biological function of TRAF3IP3 in glioma. We also examined the effects of TRAF3IP3 on glioma progression, including characteristics such as cell proliferation, migration, and invasion, using cell proliferation, wound healing, and Transwell assays, respectively, paired with in vitro glioma cell lines and in vivo mouse xenograft models to determine the molecular mechanisms underlying these effects. High TRAF3IP3 expression in glioma tissues was associated with patients with neoplasm cancer tissue source site, and poorer overall survival (OS) (p = 0.03), which was validated using TCGA. GSEA revealed the enrichment of neuroactive ligand-receptor interactions, the olfactory pathway, proteasome pathway, cytokine-cytokine receptor interactions, and calcium signaling pathway in the TRAF3IP3 high-expression phenotype. TRAF3IP3 knockdown markedly suppressed the proliferation, migration, and invasion abilities of U251 glioma cells, whereas TRAF3IP3 overexpression notably promoted the progression of U118 cell tumors. Mechanistic studies revealed that TRAF3IP3 upregulated p-ERK expression in glioma cells. Notably, the ERK signaling pathway inhibitor U0126 drastically attenuated the effects of TRAF3IP3 on p-ERK and markedly blocked its tumor-promoting activity. TRAF3IP3 overexpression also promoted in vivo tumor growth in a nude mouse xenograft model. Collectively, TRAF3IP3 stimulates glioma cell proliferation, migration, and invasion, at least partly by activating the ERK signaling pathway. We hypothesize that TRAF3IP3 may participate in glioma development via the ERK signaling pathway and that elevated TRAF3IP3 expression may serve as a potential biomarker for glioma prognosis.

Comparison of the clinical characteristics and mortalities of severe COVID-19 patients between pre- and post-menopause women and age-matched men.

The mortality rate of young female COVID-19 patients is reported to be lower than that of young males but no significant difference in mortality was found between female and male COVID-19 patients aged over 65 years, and the underlying mechanism is unknown. We retrospectively analyzed clinical characteristics and outcomes of severely ill pre- and post-menopausal COVID-19 patients and compared with age-matched males. Of the 459 patients included, 141 aged ≤55, among whom 19 died (16 males vs. 3 females, p<0.005). While for patients >55 years (n=318), 115 died (47 females vs. 68 males, p=0.149). In patients ≤55 years old, the levels of NLR, median LDH, median c-reactive protein and procalcitonin were significantly higher while the median lymphocyte count and LCR were lower in male than in female (all p<0.0001). In patients over 55, these biochemical parameters were far away from related normal/reference values in the vast majority of these patients in both genders which were in contrast to that seen in the young group. It is concluded that the mortality of severely ill pre-menopausal but not post-menopausal COVID-19 female patients is lower than age-matched male. Our findings support the notion that estrogen plays a beneficial role in combating COVID-19.

Neuroprotective Effects of Dexmedetomidine Preconditioning on Oxygen-glucose Deprivation-reoxygenation Injury in PC12 Cells via Regulation of Ca2+-STIM1/Orai1 Signaling.

Dexmedetomidine (DEX), a potent and highly selective agonist for α2-adrenergic receptors (α2AR), exerts neuroprotective effects by reducing apoptosis through decreased neuronal Ca2+ influx. However, the exact action mechanism of DEX and its effects on oxygen-glucose deprivation-reoxygenation (OGD/R) injury in vitro are unknown. We demonstrate that DEX pretreatment reduced OGD/R injury in PC12 cells, as evidenced by decreased oxidative stress, autophagy, and neuronal apoptosis. Specifically, DEX pretreatment decreased the expression levels of stromal interaction molecule 1 (STIM1) and calcium release-activated calcium channel protein 1 (Orai1), and reduced the concentration of intracellular calcium pools. In addition, variations in cytosolic calcium concentration altered apoptosis rate of PC12 cells after exposure to hypoxic conditions, which were modulated through STIM1/Orai1 signaling. Moreover, DEX pretreatment decreased the expression levels of Beclin-1 and microtubule-associated protein 1A/1B-light chain 3 (LC3), hallmark markers of autophagy, and the formation of autophagosomes. In conclusion, these results suggested that DEX exerts neuroprotective effects against oxidative stress, autophagy, and neuronal apoptosis after OGD/R injury via modulation of Ca2+-STIM1/Orai1 signaling. Our results offer insights into the molecular mechanisms of DEX in protecting against neuronal ischemia-reperfusion injury.

Ischemic postconditioning attenuates acute kidney injury following intestinal ischemia-reperfusion through Nrf2-regulated autophagy, anti-oxidation, and anti-inflammation in mice.

Intestinal ischemia-reperfusion (IIR) often occurs during and following major cardiovascular or gut surgery and causes significant organ including kidney injuries. This study was to investigate the protective effect of intestinal ischemic postconditioning (IPo) on IIR-induced acute kidney injury (AKI) and the underling cellular signaling mechanisms with focus on the Nrf2/HO-1. Adult C57BL/6J mice were subjected to IIR with or without IPo. IIR was established by clamping the superior mesenteric artery (SMA) for 45 minutes followed by 120 minutes reperfusion. Outcome measures were: (i) Intestinal and renal histopathology; (ii) Renal function; (iii) Cellular signaling changes; (iv) Oxidative stress and inflammatory responses. IPo significantly attenuated IIR-induced kidney injury. Furthermore, IPo significantly increased both nuclear Nrf2 and HO-1 expression in the kidney, upregulated autophagic flux, inhibited IIR-induced inflammation and reduced oxidative stress. The protective effect of IPo was abolished by the administration of Nrf2 inhibitor (Brusatol) or Nrf2 siRNA. Conversely, a Nrf2 activator t-BHQ has a similar protective effect to that of IPo. Our data indicate that IPo protects the kidney injury induced by IIR, which was likely mediated through the Nrf2/HO-1 cellular signaling activation.

Aggravated intestinal ischemia­reperfusion injury is associated with activated mitochondrial autophagy in a mouse model of diabetes.

Numerous studies have reported that diabetes is associated with an increased susceptibility to cardiac ischemia­ reperfusion injury; however, the mechanism underlying the role of diabetes during intestinal ischemia­reperfusion (IIR) has yet to be elucidated. The present study evaluated the intestinal pathological alterations and possible underlying mechanisms in a mouse model of type 1 diabetes mellitus with IIR. The effects of diabetes were investigated by assessing the histopathology, oxidative stress, inflammatory cytokine levels in intestine tissues and blood plasma, and protein expression levels of phosphatase and tensin homolog­induced putative kinase (PINK1), Parkin and the ratio of light chain 3B (LC3B) II/I. The results demonstrated that diabetes increased the Chiu's intestinal injury score, concentration of interleukin (IL)­1ß, IL­6 and tumor necrosis factor (TNF)­α, and levels of oxidative stress. Furthermore, the alterations were more pronounced in the diabetes with IIR group. The expression levels of PINK1 and Parkin, as well as the ratio of LC3BII/I, were significantly upregulated in the IIR group compared with the Sham group. Diabetes activated PINK1 and Parkin, and increased the expression of LC3BII. Furthermore, transmission electron microscopy revealed that mitochondrial destruction and the number of autophagosomes was increased in the diabetic groups compared with the non­diabetic groups. Collectively, the results of the present study suggest that diabetes increased intestinal vulnerability to IIR by enhancing inflammation and oxidative stress. Furthermore, IIR was associated with overactivation of mitochondrial autophagy; therefore, the increased vulnerability to IIR­induced intestine damage due to diabetes may be associated with PINK1/Parkin­regulated mitochondrial autophagy.

Parasternal Intercostal Block Complementation Contributes to Postoperative Pain Relief in Modified Radical Mastectomy Employing Pectoral Nerve Block I and Serratus-Intercostal Block: A Randomized Trial.

PURPOSE: Pectoral nerve block I (PECS I) and serratus-intercostal plane block (SIPB) can anesthetize the majority mammary region, while parasternal intercostal block (PSI) targets the internal area during breast resection surgery. The aim of this study was to determine whether including PSI with PECS I and SIPB is more effective compared to PECS I and SIPB alone. PATIENTS AND METHODS: Sixty-two adult females undergoing unilateral modified radical mastectomy (MRM) were randomly assigned to receive either PECS I and SIPB (PS group, n=31) or a combination of PECS I, SIPB, and PSI (PSP group, n=31). The outcomes were measured with a numerical rating scale (NRS) score, and in terms of opioid consumption and anesthesia-related complications within 48 h after surgery. RESULTS: Although there were no differences in the NRS scores between the two groups during the inactive periods, the combination of three nerve blocks significantly reduced the NRS scores during movement. In addition, morphine equivalent consumption was lower in the PSP group compared to the PS group. Postoperative adverse events were similar in both groups in terms of regional anesthesia-related complications. CONCLUSION: The combination of PECS I block, SIPB, and PSI block provides superior pain relief and postoperative recovery for patients undergoing MRM.

Avoiding health worker infection and containing the coronavirus disease 2019 pandemic: Perspectives from the frontline in Wuhan.

Coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused great public concern worldwide due to its high rates of infectivity and pathogenicity. The Chinese government responded in a timely manner, alleviated the dilemma, achieved a huge victory and lockdown has now been lifted in Wuhan. However, the outbreak has occurred in more than 200 other countries. Globally, as of 9:56 am CEST on 19 May 2020, there have been 4,696,849 confirmed cases of COVID-19, including 315,131 deaths, reported to Word Health Organization (WHO). The spread of COVID-19 overwhelmed the healthcare systems of many countries and even crashed the fragile healthcare systems of some. Although the situation in each country is different, health workers play a critical role in the fight against COVID-19. In this review, we highlight the status of health worker infections in China and other countries, especially the causes of infection in China and the standardised protocol to protect health workers from the perspective of an anaesthesiologist, in the hope of providing references to reduce medical infections and contain the COVID-19 epidemic.

Clinical characteristics and outcomes of patients undergoing surgeries during the incubation period of COVID-19 infection.

BACKGROUND: The outbreak of 2019 novel coronavirus disease (COVID-19) in Wuhan, China, has spread rapidly worldwide. In the early stage, we encountered a small but meaningful number of patients who were unintentionally scheduled for elective surgeries during the incubation period of COVID-19. We intended to describe their clinical characteristics and outcomes. METHODS: We retrospectively analyzed the clinical data of 34 patients underwent elective surgeries during the incubation period of COVID-19 at Renmin Hospital, Zhongnan Hospital, Tongji Hospital and Central Hospital in Wuhan, from January 1 to February 5, 2020. FINDINGS: Of the 34 operative patients, the median age was 55 years (IQR, 43-63), and 20 (58·8%) patients were women. All patients developed COVID-19 pneumonia shortly after surgery with abnormal findings on chest computed tomographic scans. Common symptoms included fever (31 [91·2%]), fatigue (25 [73·5%]) and dry cough (18 [52·9%]). 15 (44·1%) patients required admission to intensive care unit (ICU) during disease progression, and 7 patients (20·5%) died after admission to ICU. Compared with non-ICU patients, ICU patients were older, were more likely to have underlying comorbidities, underwent more difficult surgeries, as well as more severe laboratory abnormalities (eg, hyperleukocytemia, lymphopenia). The most common complications in non-survivors included ARDS, shock, arrhythmia and acute cardiac injury. INTERPRETATION: In this retrospective cohort study of 34 operative patients with confirmed COVID-19, 15 (44·1%) patients needed ICU care, and the mortality rate was 20·5%. FUNDING: National Natural Science Foundation of China.

Ischemic Postconditioning Alleviates Intestinal Ischemia-Reperfusion Injury by Enhancing Autophagy and Suppressing Oxidative Stress through the Akt/GSK-3ß/Nrf2 Pathway in Mice.

AIMS: Ischemic postconditioning (IPO) has a strong protective effect against intestinal ischemia-reperfusion (IIR) injury that is partly related to autophagy. However, the precise mechanisms involved are unknown. METHODS: C57BL/6J mice were subjected to unilateral IIR with or without IPO. After 45 min ischemia and 120 min reperfusion, intestinal tissues and blood were collected for examination. HE staining and Chiu's score were used to evaluate pathologic injury. We test markers of intestinal barrier function and oxidative stress. Finally, we used WB to detect the expression of key proteins of autophagy and the Akt/GSK-3ß/Nrf2 pathway. RESULTS: IPO significantly attenuated IIR injury. Expression levels of LC3 II/I, Beclin-1, and p62 were altered during IIR, indicating that IPO enhanced autophagy. IPO also activated Akt, inhibited GSK-3ß/Nrf2 pathway. CONCLUSION: Our study indicates that IPO can ameliorate IIR injury by evoking autophagy, activating Akt, inactivating GSK-3ß, and activating Nrf2. These findings may provide novel insights for the alleviation of IIR injury.ß/Nrf2 pathway.

Safety and efficacy of different anesthetic regimens for parturients with COVID-19 undergoing Cesarean delivery: a case series of 17 patients.

PURPOSE: To assess the management and safety of epidural or general anesthesia for Cesarean delivery in parturients with coronavirus disease (COVID-19) and their newborns, and to evaluate the standardized procedures for protecting medical staff. METHODS: We retrospectively reviewed the cases of parturients diagnosed with severe acute respiratory syndrome coronavirus (SARS-CoV-2) infection disease (COVID-19). Their epidemiologic history, chest computed tomography scans, laboratory measurements, and SARS-CoV-2 nucleic acid positivity were evaluated. We also recorded the patients' demographic and clinical characteristics, anesthesia and surgery-related data, maternal and neonatal complications, as well as the health status of the involved medical staff. RESULTS: The clinical characteristics of 17 pregnant women infected with SARS-CoV-2 were similar to those previously reported in non-pregnant adult patients. All of the 17 patients underwent Cesarean delivery with anesthesia performed according to standardized anesthesia/surgery procedures. Fourteen of the patients underwent continuous epidural anesthesia with 12 experiencing significant intraoperative hypotension. Three patients received general anesthesia with tracheal intubation because emergency surgery was needed. Three of the parturients are still recovering from their Cesarean delivery and are receiving in-hospital treatment for COVID-19. Three neonates were born prematurely. There were no deaths or serious neonatal asphyxia events. All neonatal SARS-CoV-2 nucleic acid tests were negative. No medical staff were infected throughout the patient care period. CONCLUSIONS: Both epidural and general anesthesia were safely used for Cesarean delivery in the parturients with COVID-19. Nevertheless, the incidence of hypotension during epidural anesthesia appeared excessive. Proper patient transfer, medical staff access procedures, and effective biosafety precautions are important to protect medical staff from COVID-19.

RéSUMé: OBJECTIF: Évaluer la gestion et la sécurité de l'anesthésie péridurale ou de l'anesthésie générale pour un accouchement par césarienne chez des parturientes infectées par la maladie à coronavirus 2019 (COVID-19) et pour leurs nouveau-nés, et évaluer les procédures standardisées visant la protection du personnel médical. MéTHODES: Nous avons revu de manière rétrospective les cas de parturientes ayant un diagnostic de syndrome respiratoire aigu sévère lié à l'infection (SARS-CoV-2) par le coronavirus (COVID-19). L'enquête épidémiologique, leurs examens de tomodensitométrie thoracique, les analyses de laboratoire et leur positivité pour l'acide nucléique du SARS-CoV-2 ont été évalués. Nous avons également consigné les caractéristiques démographiques et cliniques des patientes, les données liées à l'anesthésie et à la chirurgie, les complications maternelles et néonatales, ainsi que l'état de santé du personnel médical concerné. RéSULTATS: Les caractéristiques cliniques des 17 femmes enceintes infectées par le SARS-CoV-2 étaient semblables à celles précédemment rapportées chez des patientes adultes non enceintes. Les 17 patientes ont subi un accouchement par césarienne sous anesthésie effectué selon les procédures standardisées d'anesthésie et de chirurgie. Parmi les quatorze patientes ayant eu une anesthésie péridurale continue, 12 patientes ont présenté une hypotension peropératoire significative. Trois patientes ont accouché sous anesthésie générale avec intubation trachéale, car nécessitant une chirurgie d'urgence. Trois parturientes sont encore en convalescence après leur accouchement par césarienne et reçoivent un traitement à l'hôpital pour la COVID-19. Trois nouveau-nés sont nés prématurément. Il n'y a pas eu de décès ou d'événement asphyxique néonatal grave. Toutes les recherches d'acide nucléique du SARS-CoV-2 chez les nouveau-nés ont été négatives. Aucun membre du personnel médical n'a été infecté pendant la durée des soins aux patientes. CONCLUSIONS: L'anesthésie par péridurale et l'anesthésie générale ont été utilisées sans danger pour l'accouchement par césarienne de parturientes atteintes de COVID-19. Cependant, l'incidence de l'hypotension au cours de l'anesthésie péridurale a paru excessive. Un transfert approprié des patientes, les procédures d'accès du personnel médical et des précautions efficaces de biosécurité sont importants pour protéger le personnel médical contre la COVID-19.

Exendin-4 attenuates pain-induced cognitive impairment by alleviating hippocampal neuroinflammation in a rat model of spinal nerve ligation.

Glucagon-like peptide-1 receptor has anti-apoptotic, anti-inflammatory, and neuroprotective effects. It is now recognized that the occurrence and development of chronic pain are strongly associated with anti-inflammatory responses; however, it is not clear whether glucagon-like peptide-1 receptor regulates chronic pain via anti-inflammatory mechanisms. We explored the effects of glucagon-like peptide-1 receptor on nociception, cognition, and neuroinflammation in chronic pain. A rat model of chronic pain was established using left L5 spinal nerve ligation. The glucagon-like peptide-1 receptor agonist exendin-4 was intrathecally injected into rats from 10 to 21 days after spinal nerve ligation. Electrophysiological examinations showed that, after treatment with exendin-4, paw withdrawal frequency of the left limb was significantly reduced, and pain was relieved. In addition, in the Morris water maze test, escape latency increased and the time to reach the platform decreased following exendin-4 treatment. Immunohistochemical staining and western blot assays revealed an increase in the numbers of activated microglia and astrocytes in the dentate gyrus of rat hippocampus, as well as an increase in the expression of tumor necrosis factor alpha, interleukin 1 beta, and interleukin 6. All of these effects could be reversed by exendin-4 treatment. These findings suggest that exendin-4 can alleviate pain-induced neuroinflammatory responses and promote the recovery of cognitive function via the glucagon-like peptide-1 receptor pathway. All experimental procedures and protocols were approved by the Experimental Animal Ethics Committee of Renmin Hospital of Wuhan University of China (approval No. WDRM 20171214) on September 22, 2017.

Hyperglycemia-Induced Oxidative Stress Abrogates Remifentanil Preconditioning-Mediated Cardioprotection in Diabetic Rats by Impairing Caveolin-3-Modulated PI3K/Akt and JAK2/STAT3 Signaling.

Diabetic hearts are more vulnerable to ischemia/reperfusion (I/R) injury and less responsive to remifentanil preconditioning (RPC), but the underlying mechanisms are incompletely understood. Caveolin-3 (Cav-3), the dominant isoform of cardiomyocyte caveolae, is reduced in diabetic hearts in which oxidative stress is increased. This study determined whether the compromised RPC in diabetes was an independent manifestation of hyperglycemia-induced oxidative stress or linked to impaired Cav-3 expression with associated signaling abnormality. RPC significantly attenuated postischemic infarction, cardiac dysfunction, myocardial apoptosis, and 15-F2t-isoprostane production (a specific marker of oxidative stress), accompanied with increased Cav-3 expression and enhanced Akt and STAT3 activation in control but not in diabetic rats. Pretreatment with the antioxidant N-acetylcysteine (NAC) attenuated hyperglycemia-induced reduction of Cav-3 expression and Akt and STAT3 activation and restored RPC-mediated cardioprotection in diabetes, which was abolished by cardiac-specific knockdown of Cav-3 by AAV9-shRNA-Cav-3, PI3K/Akt inhibitor wortmannin, or JAK2/STAT3 inhibitor AG490, respectively. Similarly, NAC could restore RPC protection from high glucose and hypoxia/reoxygenation-induced injury evidenced by decreased levels of LDH release, 15-F2t-isoprostane, O2 -, and JC-1 monomeric cells, which were reversed by caveolae disrupter methyl-ß-cyclodextrin, wortmannin, or AG490 in isolated primary cardiomyocytes or siRNAs of Cav-3, Akt, or STAT3 in H9C2 cells. Either methyl-ß-cyclodextrin or Cav-3 knockdown reduced Akt and STAT3 activation. Further, the inhibition of Akt activation by a selective inhibitor or siRNA reduced STAT3 activation and vice versa, but they had no effects on Cav-3 expression. Thus, hyperglycemia-induced oxidative stress abrogates RPC cardioprotection by impairing Cav-3-modulated PI3K/Akt and JAK2/STAT3 signaling. Antioxidant treatment with NAC could restore RPC-induced cardioprotection in diabetes by improving Cav-3-dependent Akt and STAT3 activation and by facilitating the cross talk between PI3K/Akt and JAK2/STAT3 signaling pathways.

Propofol alleviates oxidative stress via upregulating lncRNA-TUG1/Brg1 pathway in hypoxia/reoxygenation hepatic cells.

Reducing oxidative stress is an effective method to prevent hepatic ischaemia/reperfusion injury (HIRI). This study focuses on the role of propofol on the oxidative stress of hepatic cells and the involved lncRNA-TUG1/Brahma-related gene 1 (Brg1) pathway in HIRI mice. The mouse HIRI model was established and was intraperitoneally injected with propofol postconditioning. Hepatic injury indexes were used to evaluate HIRI. The oxidative stress was indicated by increasing 8-isoprostane concentration. Mouse hepatic cell line AML12 was treated with hypoxia and subsequent reoxygenation (H/R). The targeted regulation of lncRNA-TUG1 on Brg1 was proved by RNA pull-down, RIP (RNA-binding protein immunoprecipitation) and the expression level of Brg1 responds to silencing or overexpression of lncRNA-TUG1. Propofol alleviates HIRI and induces the upregulation of lncRNA-TUG1 in the mouse HIRI model. Propofol increases cell viability and lncRNA-TUG1 expression level in H/R-treated hepatic cells. In H/R plus propofol-treated hepatic cells, lncRNA-TUG1 silencing reduces cell viability and increased oxidative stress. LncRNA-TUG1 interacts with Brg1 protein and keeps its level via inhibiting its degradation. Brg1 overexpression reverses lncRNA-TUG1 induced the reduction of cell viability and the increase in oxidative stress. LncRNA-TUG1 silencing abrogates the protective role of propofol against HIRI in the mouse HIRI model. LncRNA-TUG1 has a targeted regulation of Brg1, and thereby affects the oxidative stress induced by HIRI. This pathway mediates the protective effect of propofol against HIRI of hepatic cell.

The Pathway of Let-7a-1/2-3p and HMGB1 Mediated Dexmedetomidine Inhibiting Microglia Activation in Spinal Cord Ischemia-Reperfusion Injury Mice.

Microglial cell activation after spinal cord ischemia-reperfusion injury (SCIRI) commonly causes the secondary nerve motion function injury. This study aims to study the mechanism by which the drug dexmedetomidine (DEX) inhibits microglial cell activation and improves motion function of SCIRI mice. Mice SCIRI model was established, and microglia from spinal cord were isolated and cultured for subsequent molecule analysis of let-7a-1-3p, let-7a-2-3p, HMGB1, TNF-α, and IL-6. DEX was given by intraperitoneal injection. Mice motion function was evaluated by Basso mouse score. In vitro microglial cells were subjected to oxygen and glucose deprivation/reoxygenation (OGD/R) to imitate ischemia-reperfusion injury stimulation. DEX injection improves the mouse motion function in SCIRI model and upregulates let-7a-1/2-3p expression in the isolated activated microglia from SCIRI mice. In OGD/R-stimulated microglia, DEX treatment also caused the inactivation of cells, the upregulation of let-7a-1/2-3p expression, and the downregulation of HMGB1 expression. While the co-silencing of let-7a-1/2-3p in microglia in addition to DEX treatment restored the activation of microglia. HMGB1 is a targeted gene for let-7a-1/2-3p and negatively regulated by them. HMGB1 knockdown abrogates the pro-activation impact on microglial cell by let-7a-1/2-3p silencing. DEX inhibits the activation of microglial cell in the spinal cord of SCIRI mice, mediated by the let-7a-1/2-3p/HMGB1 pathway.

Dexmedetomidine preconditioning protects against lung injury in hemorrhagic shock rats / Pré-condicionamento com dexmedetomidina protege contra lesão pulmonar em ratos com choque hemorrágico

Abstract Background and objectives: Dexmedetomidine has demonstrated protective effects against lung injury in vitro. Here, we investigated whether dexmedetomidine preconditioning protected against lung injury in hemorrhagic shock rats. Methods: Male Sprague-Dawley rats were randomly divided into four groups (n = 8): control group, hemorrhagic shock group, 5 ug.kg-1 dexmedetomidine (DEX1) group, and 10 ug.kg-1 dexmedetomidine (DEX2) group. Saline or dexmedetomidine were administered over 20 min. 30 min after injection, hemorrhage was initiated in the hemorrhagic shock, DEX1 and DEX2 group. Four hours after resuscitation, protein and cellular content in bronchoalveolar lavage fluid, and the lung histopathology were measured. The malondialdehyde, superoxide dismutase, Bcl-2, Bax and caspase-3 were also tested in the lung tissue. Results: Compare with hemorrhagic shock group, 5 ug.kg-1 dexmedetomidine pretreatment reduced the apoptosis (2.25 ± 0.24 vs. 4.12 ± 0.42%, p < 0.05), histological score (1.06 ± 0.12 vs. 1.68 ± 0.15, p < 0.05) and protein (1.92 ± 0.38 vs. 3.95 ± 0.42 mg.mL-1, p < 0.05) and WBC (0.42 ± 0.11 vs. 0.92 ± 0.13 × 109/L, p < 0.05) in bronchoalveolar lavage fluid. Which is correlated with increased superoxide dismutase activity (8.35 ± 0.68 vs. 4.73 ± 0.44 U.mg-1 protein, p < 0.05) and decreased malondialdehyde (2.18 ± 0.19 vs. 3.28 ± 0.27 nmoL.mg-1 protein, p < 0.05). Dexmedetomidine preconditioning also increased the Bcl-2 level (0.55 ± 0.04 vs. 0.34 ± 0.05, p < 0.05) and decreased the level of Bax (0.46 ± 0.03 vs. 0.68 ± 0.04, p < 0.05), caspase-3 (0.49 ± 0.03 vs. 0.69 ± 0.04, p < 0.05). However, we did not observe any difference between the DEX1 and DEX2 groups for these (p > 0.05). Conclusion: Dexmedetomidine preconditioning has a protective effect against lung injury caused by hemorrhagic shock in rats. The potential mechanisms involved are the inhibition of cell death and improvement of antioxidation. But did not show a dose-dependent effect.

Resumo Justificativa e objetivos: Dexmedetomidina demonstrou efeitos protetores contra a lesão pulmonar in vitro. Neste estudo, investigamos se o pré-condicionamento com dexmedetomidina protege contra a lesão pulmonar em ratos com choque hemorrágico. Métodos: Ratos machos, Sprague-Dawley, foram aleatoriamente divididos em quatro grupos (n = 8): grupo controle, grupo com choque hemorrágico, grupo com 5 µg.kg-1 de dexmedetomidina (DEX1) e grupo com 10 µg.kg-1 de dexmedetomidina (DEX2). Solução salina ou dexmedetomidina foi administrada durante 20 minutos. Trinta minutos após a injeção, a hemorragia foi iniciada nos grupos choque hemorrágico, DEX1 e DEX2. Quatro horas após a ressuscitação, a proteína e o conteúdo celular no lavado broncoalveolar e a histopatologia pulmonar foram medidos. Malondialdeído, superóxido dismutase, Bcl-2, Bax e caspase-3 também foram testados no tecido pulmonar. Resultados: Na comparação com o grupo choque hemorrágico, o pré-tratamento com 5 ug.kg-1 de dexmedetomidina reduziu a apoptose (2,25 ± 0,24 vs. 4,12 ± 0,42%, p < 0,05), escore histológico (1,06 ± 0,12 vs. 1,68 ± 0,15, p < 0,05) e proteína (1,92 ± 0,38 vs. 3,95 ± 0,42 mg.mL-1, p < 0,05) e leucócitos (0,42 ± 0,11 vs. 0,92 ± 0,13 × 109/L, p < 0,05) no lavado broncoalveolar; o que está correlacionado com o aumento da atividade da superóxido dismutase (8,35 ± 0,68 vs. 4,73 ± 0,44 U.mg-1 de proteína, p < 0,05) e diminuição do malondialdeído (2,18 ± 0,19 vs. 3,28 ± 0,27 nmoL.mg-1 de proteína, p < 0,05). O pré-condicionamento com dexmedetomidina também aumentou o nível de Bcl-2 (0,55 ± 0,04 vs. 0,34 ± 0,05, p < 0,05) e diminuiu o nível de Bax (0,46 ± 0,03 vs. 0,68 ± 0,04, p < 0,05), caspase-3 (0,49 ± 0,03 vs. 0,69 ± 0,04, p < 0,05). No entanto, não houve diferença entre os grupos DEX1 e DEX2 para essas proteínas (p > 0,05). Conclusão: O pré-condicionamento com dexmedetomidina tem um efeito protetor contra a lesão pulmonar causada por choque hemorrágico em ratos. Os potenciais mecanismos envolvidos são a inibição da morte celular e a melhora da antioxidação. Porém, não mostrou um efeito dose-dependente.

Honokiol-Mediated Mitophagy Ameliorates Postoperative Cognitive Impairment Induced by Surgery/Sevoflurane via Inhibiting the Activation of NLRP3 Inflammasome in the Hippocampus.

BACKGROUND: The potential mechanism of postoperative cognitive impairment is still largely unclear. The activation of NLRP3 inflammasome had been reported to be involved in neurodegenerative diseases, including postoperative cognitive change, and is closely related to mitochondrial ROS and mitophagy. Honokiol (HNK) owns multiple organic protective effects. This study is aimed at observing the neuroprotective effect of HNK in postoperative cognitive change and examining the role of HNK in the regulation of mitophagy and the relationship between these effects and NLRP3 inflammasome activation in mice induced by surgery/anesthesia. METHODS: In this study, mice were divided into several groups: control group, surgery group, surgery+HNK group, and surgery+HNK+3-methyladenine (3-MA) group. Hippocampal tissue samples were harvested and used for proinflammatory cytokines, mitochondrial ROS, and malondialdehyde (MDA) assay. The process of mitophagy and the activation of NLRP3 inflammasome were observed by Western blot, immunohistochemistry, and transmission electron microscopy. RESULTS: The results showed that HNK treatment obviously recovered the postoperative decline and enhanced the expressions of LC3-II, Beclin-1, Parkin, and PINK1 at protein levels after surgery/sevoflurane treatment, which are both an autophagy marker and a mitophagy marker. In addition, HNK attenuated mitochondrial structure damage and reduced mtROS and MDA generation, which are closely associated with NLRP3 inflammasome activation. Honokiol-mediated mitophagy inhibited the activation of NLRP3 inflammasome and neuroinflammation in the hippocampus. Using 3-MA, an autophagy inhibitor, the neuroprotective effects of HNK on mitophagy and NLRP3 inflammasome activation were eliminated. CONCLUSION: These results indicated that HNK-mediated mitophagy ameliorates postoperative cognitive impairment induced by surgery/sevoflurane. This neuroprotective effect may be involved in inhibiting the activation of NLRP3 inflammasome and suppressing inflammatory responses in the hippocampus.

Inhibition of HDAC3 Ameliorates Cerebral Ischemia Reperfusion Injury in Diabetic Mice In Vivo and In Vitro.

BACKGROUND: A substantial increase in histone deacetylase 3 (HDAC3) expression is implicated in the pathological process of diabetes and stroke. However, it is unclear whether HDAC3 plays an important role in diabetes complicated with stroke. We aimed to explore the role and the potential mechanisms of HDAC3 in cerebral ischemia/reperfusion (I/R) injury in diabetic state. METHODS: Diabetic mice were subjected to 1 h ischemia, followed by 24 h reperfusion. PC12 cells were exposed to high glucose for 24 h, followed by 3 h of hypoxia and 6 h of reoxygenation (H/R). Diabetic mice received RGFP966 (the specific HDAC3 inhibitor) or vehicle 30 minutes before the middle cerebral artery occlusion (MCAO), and high glucose-incubated PC12 cells were pretreated with RGFP966 or vehicle 6 h before H/R. RESULTS: HDAC3 inhibition reduced the cerebral infarct volume, ameliorated pathological changes, improved the cell viability and cytotoxicity, alleviated apoptosis, attenuated oxidative stress, and enhanced autophagy in cerebral I/R injury model in diabetic state in vivo and in vitro. Furthermore, we found that the expression of HDAC3 was remarkably amplified, and the Bmal1 expression was notably decreased in diabetic mice with cerebral I/R, whereas this phenomenon was obviously reversed by RGFP966 pretreatment. CONCLUSIONS: These results suggested that the HDAC3 was involved in the pathological process of the complex disease of diabetic stroke. Suppression of HDAC3 exerted protective effects against cerebral I/R injury in diabetic state in vivo and in vitro via the modulation of oxidative stress, apoptosis, and autophagy, which might be mediated by the upregulation of Bmal1.

[Dexmedetomidine preconditioning protects against lung injury in hemorrhagic shock rats]. / Pré­condicionamento com dexmedetomidina protege contra lesão pulmonar em ratos com choque hemorrágico.

BACKGROUND AND OBJECTIVES: Dexmedetomidine has demonstrated protective effects against lung injury in vitro. Here, we investigated whether dexmedetomidine preconditioning protected against lung injury in hemorrhagic shock rats. METHODS: Male Sprague-Dawley rats were randomly divided into four groups (n=8): control group, hemorrhagic shock group, 5ug.kg-1 dexmedetomidine (DEX1) group, and 10ug.kg-1 dexmedetomidine (DEX2) group. Saline or dexmedetomidine were administered over 20min. 30min after injection, hemorrhage was initiated in the hemorrhagic shock, DEX1 and DEX2 group. Four hours after resuscitation, protein and cellular content in bronchoalveolar lavage fluid, and the lung histopathology were measured. The malondialdehyde, superoxide dismutase, Bcl-2, Bax and caspase-3 were also tested in the lung tissue. RESULTS: Compare with hemorrhagic shock group, 5ug.kg-1 dexmedetomidine pretreatment reduced the apoptosis (2.25±0.24 vs. 4.12±0.42%, p<0.05), histological score (1.06±0.12 vs. 1.68±0.15, p<0.05) and protein (1.92±0.38 vs. 3.95±0.42mg.mL-1, p<0.05) and WBC (0.42±0.11 vs. 0.92±0.13×109/L, p<0.05) in bronchoalveolar lavage fluid. Which is correlated with increased superoxide dismutase activity (8.35±0.68 vs. 4.73±0.44U.mg-1 protein, p<0.05) and decreased malondialdehyde (2.18±0.19 vs. 3.28±0.27nmoL.mg-1 protein, p<0.05). Dexmedetomidine preconditioning also increased the Bcl-2 level (0.55±0.04 vs. 0.34±0.05, p<0.05) and decreased the level of Bax (0.46±0.03 vs. 0.68±0.04, p<0.05), caspase-3 (0.49±0.03 vs. 0.69±0.04, p<0.05). However, we did not observe any difference between the DEX1 and DEX2 groups for these (p>0.05). CONCLUSION: Dexmedetomidine preconditioning has a protective effect against lung injury caused by hemorrhagic shock in rats. The potential mechanisms involved are the inhibition of cell death and improvement of antioxidation. But did not show a dose-dependent effect.