Hyperbaric Lidocaine Aggravates Diabetic Neuropathic Pain by Targeting p38 MAPK/ERK and PINK1/Parkin-Mediated Mitophagy Signaling Pathway.

BACKGROUND: Diabetic neuropathic pain (DNP) is a complication of diabetes mellitus (DM). Hyperbaric lidocaine (HL), a local anesthetics drug, has neurotoxicity. The present study aims to study the effect and molecular mechanisms of HL on spinal nerve injury in DNP. METHODS: The DNP rat model was established through a high-fat-glucose diet in combination with Streptozotocin (STZ) administration. SB203580 and PD98059 were utilized to inhibit p38 mitogen-activated protein kinase (p38 MAPK) and extracellular signal-regulated kinase (ERK). The mechanical paw withdrawal threshold (PWT) and the thermal paw withdrawal latency (PWL) were tested to evaluate rats' mechanical allodynia and thermal hyperalgesia. Hematoxylin-eosin (H&E) and terminal deoxynucleotidyltransferase-mediated dUTP nick-end Labeling (TUNEL) staining were performed to evaluate the pathological changes and neuron apoptosis in spinal cord tissues of L4-5. Western blotting analysis and reverse transcription-polymerase chain reaction (RT-qPCR) assay were used to measure the levels of proteins and mRNAs, respectively. RESULTS: PWT and PWL were decreased in DNP rats with serious spinal nerve injury. HL administration downregulated the PWT and PWL and aggravated spinal nerve injury in DNP rats, but isobaric lidocaine had no effects on these changes. Meanwhile, p38 MAPK/ERK signaling and PTEN-induced kinase 1 (PINK1)-mediated mitophagy were activated in DNP, which was enhanced by HL but not isobaric lidocaine. Blocking p38 MAPK/ERK signaling could effectively attenuate HL-induced spinal nerve injury and inhibit mitophagy. CONCLUSION: In summary, HL can aggravate spinal cord tissue damage in DNP rats by inducing PINK1-mediated mitophagy via activating p38 MAPK/ERK signaling. Our data provide a novel insight that supports the potential role of p38 MAPK/ERK signaling in acting as a therapeutic target for HL-induced neurotoxicity.

miR-182-5p Delivered by Plasma Exosomes Promotes Sevoflurane-Induced Neuroinflammation and Cognitive Dysfunction in Aged Rats with Postoperative Cognitive Dysfunction by Targeting Brain-Derived Neurotrophic Factor and Activating NF-κB Pathway.

The objective of this study was to discuss the possible mechanism and effect of miR-182-5p delivered by plasma exosomes on sevoflurane-induced neuroinflammation and cognitive disorder in aged rats with postoperative cognitive dysfunction (POCD). Firstly, aged POCD rat models were constructed by sevoflurane anesthesia and superior mesenteric artery occlusion. Subsequently, exosomes and miR-182-5p were inhibited by injection of GW4869 and miR-182-5p-sponge, respectively. Then, exosomes were extracted from the plasma of rats in each group, followed by the determination of the morphology and diameters of exosomes as well as the expression of exosome markers CD63 and CD81 by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and Western blot. Besides, the Morris water maze (MWM) and fear conditioning test were used to evaluate the learning and memory ability of rats; Western blot to detect the expression levels of neurotrophic factors (brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF)) as well as NF-κB pathway-related proteins (p65 and p-p65) in rat hippocampal tissues or PC-12 cells; qRT-PCR to assess the expression levels of miR-182-5p and BDNF in rat plasma, plasma exosomes, hippocampal tissues, and PC-12 cells; ELISA to evaluate the levels of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1ß in rat hippocampal tissues; and dual-luciferase reporter assay to verify the targeting relationship between miR-182-5p and BDNF. After examination, the results were obtained as follows. miR-182-5p expression was up-regulated in POCD rats and could be delivered by plasma exosomes. Inhibition of plasma exosomes or miR-182-5p could significantly ameliorate learning and memory disorders; decrease the levels of pro-inflammatory cytokines TNF-α, IL-6, and IL-1ß; increase the expression of BDNF and NGF; and inhibit the activity of NF-κB signaling pathway in POCD rat hippocampus. In addition, miR-182-5p could also target and inhibit BDNF. All in all, miR-182-5p delivered by plasma exosomes promotes sevoflurane-induced neuroinflammation and cognitive dysfunction in aged POCD rats by targeting BDNF and activating the NF-κB pathway.

Effects of prolonged cold-ischemia on autophagy in the graft lung in a rat orthotopic lung transplantation model.

INTRODUCTION: Ischemia-reperfusion (I/R) injury causes present challenges in the field of graft transplantation which is also a major contributor to early graft dysfunction or failure after organ transplantation. The study focuses on the effects of prolonged cold-ischemia (CI) on the autophagic activity in the graft lung in a rat orthotopic lung transplantation model. MATERIAL AND METHODS: Donor lungs were preserved under CI conditions for different periods. An orthotopic lung transplantation model was developed, and the lung tissues from donor lungs subjected to CI preservation and reperfusion were harvested. We evaluated the effects of different CI periods on autophagy, reactive oxygen species (ROS) and glucose consumption. Additionally, the mechanism by which prolonged CI affected autophagy was investigated through determination of the molecules related to the mTOR pathway after treatment with 3-Methyladenine (3-MA), rapamycin and an adenosine triphosphate (ATP) synthase inhibitor oligomycin (OM). RESULTS: Prolonged CI led to increased activities of key glycolytic enzymes, glucose consumption and lactic acid production. Autophagy, ROS and glucose consumption were induced in the graft lung after I/R, which reached peak levels after 6 h and was gradually decreased. Most importantly, the perfusion treatment of 3-MA or OM decreased ROS level and autophagy, but increased the extent of mTOR phosphorylation, while the perfusion treatment of rapamycin induced ROS and autophagy. CONCLUSION: Taken together, autophagy mediated by a prolonged CI preservation affects the glucose consumption and ROS production in the graft lung via the mTOR signaling pathway.

Polygonatum sibiricum polysaccharides prevent LPS-induced acute lung injury by inhibiting inflammation via the TLR4/Myd88/NF-κB pathway.

Inflammation plays an important role in cases of acute lung injury (ALI), and the Toll-like receptor 4/nuclear factor-κB (TLR4/NF-κB) pathway, which can be regulated by Polygonatum sibiricum polysaccharides (PSPs), is closely related to the dynamics of lipopolysaccharide (LPS)-induced inflammation. Thus, we sought to evaluate whether or not PSPs prevent LPS-induced ALI by way of inhibiting inflammation via the TLR4/NF-κB pathway in rats. We established an ALI rat model by tracheal instillation of LPS, and by pre-injection of PSPs into rats to examine PSPs in the ALI rat model. We found that PSPs attenuated LPS-induced lung pathological changes in ALI rats, decreased LPS-induced myeloperoxidase (MOP) activity, and elevated malondialdehyde (MDA) levels in lung tissue. However, PSPs also decreased the LPS-induced increase in the neutrophil ratio, and decreased inflammatory factor levels in bronchoalveolar lavage fluid (BALF). Moreover, PSPs decreased LPS-induced increases in inflammatory factors measured by mRNA expression, and altered the levels of expression of TLR4, medullary differentiation protein 88 (Myd88), p-IKB-α/IKB-α and p-p65/p65 proteins in lung tissue. In vitro, PSPs also reduced apoptosis induced by LPS in BEAS-2B cells by suppressing inflammation through its effect of inhibiting the TLR4/NF-κB pathway. In conclusion, our results suggest that PSPs may be a potential drug for effective treatment of LPS-induced ALI, due to the ability to inhibit inflammation through effects exerted on the TLR4/Myd88/NF-κB pathway.

[Effect of auricular magnetic bead pressing on maternal body temperature, inflammatory response and placental pathological results in labor analgesia].

OBJECTIVE: To observe the effects of auricular magnetic bead pressing on maternal body temperature, inflammatory response and placental pathological results in epidural labor analgesia. METHODS: 180 parturient who volunteered for labor analgesia were randomly divided into epidural group (n=90, epidural labor analgesia) and auricular pressing group (n=90, epidural labor analgesia combined auricular pressing). The tympanic temperature before labor analgesia (T1), 2 h (T2), 4 h (T3) and 4 h after labor analgesia (T4) were recorded. The total duration of labor, duration of labor analgesia, PCEA compression times, labor analgesia dose, cesarean section rate was counted, and the changes in serum IL-6 level and placental pathologyresults of the two groups were analyzed. RESULTS: There was no significant difference in age, BMI, gestational age, duration of labor, duration of analgesia and rate of cesarean section between groups(P>0.05). Times of PCEA compressions and labor analgesic dose in auricular group were lower than that in epidural group (P<0.05). There was no difference in tympanic temperature between two groups at T1 (P>0.05), and the tympanic temperature at T3 and T4 was higher than that at T1 (P<0.05). The tympanic temperature in T3 and T4, and incidence of intrapartum fever in the auricular group was lower than that in the epidural group (P<0.05).There was no difference in the prenatal serum IL-6 level between groups (P>0.05), and the postpartum serum IL-6 level was higher than that before labor in either group (P<0.05).The postpartum serum IL-6 level and the incidence of HCA in the auricular point group were lower than those in epidural group (P<0.05). CONCLUSION: Magnetic beads auricular pressing therapy has advantages in reducing intrapartum fever by modulating maternal inflammation and reducing the dosage of local anesthetics effectively during epidural labor analgesia.

[Effect of magnetic beads auricular point sticking therapy on intrapartum fever in primipara with epidural labor analgesia].

OBJECTIVE: To observe effect of magnetic beads auricular point sticking therapy on intrapartum fever in primipara with epidural labor analgesia and explore its possible mechanism. METHODS: A total of 160 primipara were randomly divided into an observation group (80 cases, 12 cases dropped off ) and a control group (80 cases, 15 cases dropped off ). The primipara in the control group received epidural labor analgesia. In the observation group, 15 min after epidural labor analgesia was performed, magnetic beads auricular point sticking therapy was given at shenmen (TF4), neishengzhiqi (TF2), neifenmi (CO18) and jiaogan (AH6a), pressing and kneading once every 15 min, 1 min each time, until the end of first stage of labor. The tympanic temperature on Ta (before labor analgesia), Tb (2 h after labor analgesia), Tc (4 h after labor analgesia) and Td (1 h after labor) was recorded, and the intrapartum fever incidence and level of serum cortisol and IL-6 between two groups were compared. The visual analogue scale (VAS) score before and after labor analgesia, the pressing times of patient controlled epidural analgesia (PCEA), and the dosage of sufentanil were observed. The active labor period, the second stage of labor, and the time of analgesia, the use of oxytocin, the number of vaginal examination and the rate of cesarean section were recorded in the two groups. RESULTS: There was no significant difference in tympanic temperature in the observation group at each time point (P>0.05), the tympanic temperature at Tc and Td in the control group was higher than that at Ta (P<0.05); the tympanic temperature at Tc and Td in the observation group was lower than that in the control group (P<0.05). The levels of serum cortisol and IL-6 at Td in the two groups were higher than those at Ta (P<0.05), and those in the observation group were lower than the control group (P<0.05). The second stage of labor in the observation group was shorter than that in the control group (P<0.05), and the pressing times of PCEA, the dosage of sufentanil, intrapartum fever incidence, usage rate and total amount of oxytocin and the number of vaginal examinations were all lower than those in the control group (P<0.05). CONCLUSION: Magnetic beads auricular point sticking therapy can reduce the amount of anesthetics, decrease the effect of epidural analgesia on primipara's body temperature regulation and labor progress, and lower the incidence of fever during labor analgesia by regulating the level of inflammatory response in the primipara.

Inhibition of mitochondrial autophagy protects donor lungs for lung transplantation against ischaemia-reperfusion injury in rats via the mTOR pathway.

Impaired mitochondrial function is a key factor attributing to lung ischaemia-reperfusion (IR) injury, which contributes to major post-transplant complications. Thus, the current study was performed to investigate the role of mitochondrial autophagy in lung I/R injury and the involvement of the mTOR pathway. We established rat models of orthotopic left lung transplantation to investigate the role of mitochondrial autophagy in I/R injury following lung transplantation. Next, we treated the donor lungs with 3-MA and Rapamycin to evaluate mitochondrial autophagy, lung function and cell apoptosis with different time intervals of cold ischaemia preservation and reperfusion. In addition, mitochondrial autophagy, and cell proliferation and apoptosis of pulmonary microvascular endothelial cells (PMVECs) exposed to hypoxia-reoxygenation (H/R) were monitored after 3-MA administration or Rapamycin treatment. The cell apoptosis could be inhibited by mitochondrial autophagy at the beginning of lung ischaemia, but was rendered out of control when mitochondrial autophagy reached normal levels. After I/R of donor lung, the mitochondrial autophagy was increased until 6 hours after reperfusion and then gradually decreased. The elevation of mitochondrial autophagy was accompanied by promoted apoptosis, aggravated lung injury and deteriorated lung function. Moreover, the suppression of mitochondrial autophagy by 3-MA inhibited cell apoptosis of donor lung to alleviate I/R-induced lung injury as well as inhibited H/R-induced PMVEC apoptosis, and enhanced its proliferation. Finally, mTOR pathway participated in I/R- and H/R-mediated mitochondrial autophagy in regulation of cell apoptosis. Inhibition of I/R-induced mitochondrial autophagy alleviated lung injury via the mTOR pathway, suggesting a potential therapeutic strategy for lung I/R injury.

Comprehensive preoperative regime of selective gut decontamination in combination with probiotics, and smectite for reducing endotoxemia and cytokine activation during cardiopulmonary bypass: A pilot randomized, controlled trial.

BACKGROUND: Both selective digestive decontamination (SDD) and probiotics have been reported to reduce endotoxemia. However, the available results are conflicting and few studies have investigated the combined effect of SDD and probiotics. This study aimed to examine the effectiveness of a comprehensive preoperative regimen of SDD in combination with probiotics and smectite on perioperative endotoxemia and cytokine activation in patients who underwent elective cardiac surgery with cardiopulmonary bypass (CPB) in a pilot, prospective, randomized, controlled trial. METHODS: Patients who underwent elective Aortic Valve Replacement or Mitral Valve Replacement surgery from July 2010 to March 2015 were included. In total, 30 eligible patients were randomly assigned to receive either the comprehensive preoperative regimen (n = 15) (a combination of preoperative SDD, probiotics, and smectite) or the control group (n = 15) who did not receive this treatment. The levels of endotoxin, IL-6, and procalcitonin were measured at the time before anesthesia induction, immediately after cardiopulmonary bypass (CPB), 24 hours after CPB, and 48 hours after CPB. The primary outcomes were changes in endotoxin, IL-6, and procalcitonin concentrations after CPB. RESULTS: The mean levels of change in endotoxin levels after CPB in patients receiving the comprehensive preoperative regimen was marginally significantly lower than those in control group (F = 4.0, P = .0552) but was not significantly different for procalcitonin (F = .14, P = .7134). An interaction between group and time for IL-6 was identified (F = 4.35, P = .0231). The increase in IL-6 concentration immediately after CPB in the comprehensive preoperative group was significantly lower than that in the control group (P = .0112). The changes in IL-6 concentration at 24 hours and 48 hours after CPB were not significant between the comprehensive preoperative group and control group. CONCLUSION: The present pilot, prospective, randomized, controlled study in patients undergoing cardiac surgery with CPB demonstrated that 3 days of a comprehensive preoperative regime of SDD in combination with probiotics and smectite may reduce the endotoxin and IL-6 levels after CPB compared with the control group.

Effect of dexmedetomidine priming on convulsion reaction induced by lidocaine.

To study the effect of dexmedetomidine priming on convulsion reaction induced by lidocaine.The New Zealand white rabbits were applied for the mechanism study of dexmedetomidine priming for preventing convulsion reaction induced by lidocaine. The influence of dexmedetomidine priming with different doses on the time for convulsion occurrence and the duration time of convulsion induced by lidocaine, as well as contents of excitatory amino acids (aspartate [Asp], glutamate [Glu]) and inhibitory amino acids (glycine [Gly], γ-aminobutyric acid [GABA]) in the brain tissue were investigated.With 3 and 5 µg/kg dexmedetomidine priming, the occurrence times of convulsion were prolonged from 196 seconds to 349 and 414 seconds, respectively. With dexmedetomidine priming, the contents of excitatory amino acids (Asp, Glu) were much reduced at occurrence time of convulsion comparing with that without dexmedetomidine priming, while content of inhibitory amino acids Gly was much enhanced.The application of dexmedetomidine before local anesthetics can improve intoxication dose threshold of the lidocaine, delay occurrence of the convulsion, and helped for the recovery of convulsion induced by lidocaine. The positive effect of dexmedetomidine on preventing convulsion would owe to not only the inhibition of excitatory amino acids (Asp, Glu), but also the promotion of inhibitory amino acids Gly secretion.

Sarcandra glabra combined with lycopene protect rats from lipopolysaccharide induced acute lung injury via reducing inflammatory response.

Sarcandra glabra (Chinese name, Zhongjiefeng) is an important herb widely used in traditional Chinese medicine. Lycopene has been shown to be a powerful antioxidant. This study aims to test the hypothesis that Sarcandra glabra combined with lycopene protect rats from lipopolysaccharide (LPS) induced acute lung injury (ALI). Metabolomics approach combined with pathological inspection, serum biochemistry examination, enzyme-linked immunosorbent assay and western blotting were used to explore the protective effects of Sarcandra glabra and lycopene on LPS-induced ALI, and to elucidate the underlying mechanisms. Results showed that Sarcandra glabra and lycopene could significantly ameliorate LPS-induced histopathological injuries, improve the anti-oxidative activities of rats, decrease the levels of TNF-α and IL-6, suppress the activations of MAPK and transcription factor NF-κB and reverse the disturbed metabolism towards the normal status. Taken together, this integrated study revealed that Sarcandra glabra combined with lycopene had great potential in protecting rats from LPS-induced ALI, which would be helpful to guide the clinical medication.

Effects of morphine and sufentanil preconditioning against myocardial ischemic-reperfusion injury in rabbits.

OBJECTIVE: This study aims to explore the treatment method of myocardial ischemia-reperfusion injury. METHODS: Myocardial Ischemia-reperfusion rabbit model was established in this study. They were divided into four groups: sham operation (S) group, IRI control (I/R) group and IRI with morphine (MF) group and sufentanil (SF). Myocardial infarct size was compared with HE staining method. TUNEL assay was used to detect cell apoptosis. RESULTS: Myocardial infarct size of control group and morphine and sufetanil group was 36.0±3.6, 23.0±1.2 and 27.1±2.3, respectively. There were significant differences between them (P < 0.01). Apoptotic index of I/R, MF and SF groups was 26.9±2.2, 12.5±2.3, 15.8±2.0, with statistical significance (P < 0.05). The concentration of CK-MB in serum: there were no significant differences of CK-MB between each group at baseline. The concentration of CK-MB after reperfusion were higher than that of baseline, except for group S (P < 0.05); Compared with group S, after reperfusion, the CK-MB of other three groups were higher (P < 0.05); The concentration of CK-MB in group MF and SF were lower than group I/R (P < 0.05); In contrast to group MF, the concentration of CK-MB after reperfusion was higher in group SF (P < 0.05). CONCLUSION: Morphine and sufentanil can specifically protect the myocardial function.