[Exosomes derived from bone marrow mesenchymal stem cells regulate NF-κB pathway and reduce lung ischemia-reperfusion injury in rats by miR-335].

This study aimed to investigate the effect of exosomes derived from bone marrow mesenchymal stem cells (BMSCs-EXO) on lung ischemia-reperfusion injury (IRI) in rats and to explore the role of miR-335. The model of rat lung IRI was established by clipping the hilum of left lung for 60 min and opening for 180 min. Forty Sprague-Dawley rats were randomly divided into sham group, IRI group, IRI+PBS group, IRI+EXO group, and IRI+miR-335 inhibitor EXO (IRI+inhibitor-EXO) group (n = 8). Rats in the sham group underwent thoracotomies without IRI. Rats in the IRI group were used to establish IRI model without any additional treatment. In the IRI+PBS, IRI+EXO, and IRI+inhibitor-EXO groups, the rats were used to establish IRI model and given PBS, EXO from BMSCs without any treatment, and EXO from BMSCs with miR-335 inhibitor treatment before reperfusion, respectively. Blood gases were analyzed during the experiment. Lung tissue wet/dry ratio (W/D), interleukin 1ß (IL-1ß), tumor necrosis factor α (TNF-α), myeloperoxidase (MPO), malondialdehyde (MDA), and superoxide dismutase (SOD) were measured at the end of reperfusion. Mitochondria were observed by electron microscopy and the Flameng scores were counted. Lung histopathology and apoptosis (TUNEL staining) were observed by light microscopy, and the lung injury scores (LIS) and apoptosis index (AI) were detected. The miR-335 expression was detected by RT-qPCR, and the expression of caspase-3, cleaved-caspase-3, caspase-9, cleaved-caspase-9, and NF-κB proteins were detected by Western blot at the end of reperfusion. The results showed that compared with the sham group, the oxygenation index, pH, and base excess (BE) were significantly lower in the IRI group and IRI+PBS group after reperfusion, whereas those indices were significantly higher in the IRI+EXO group than those in the IRI+PBS group (P < 0.05). Compared with the sham group, there were significant increases in W/D, IL-1ß, TNF-α, MPO, MDA, LIS, AI, Flameng score, caspase-3, cleaved-caspase-3, caspase-9, and cleaved-caspase-9, however significant decreases in the SOD, miR-335 and NF-κB in the IRI group (P < 0.05). These indices in the IRI and IRI+PBS groups showed no significant differences. Compared with the IRI+PBS group, there were significant decreases in W/D, IL-1ß, TNF-α, MPO, MDA, LIS, AI, Flameng score, caspase-3, cleaved-caspase-3, caspase-9, and cleaved-caspase-9, however significant increases in the SOD, miR-335 and NF-κB in the IRI+EXO group (P < 0.05). While, the changes of the above mentioned indices were reversed in the IRI+inhibitor-EXO group compared with IRI+EXO group, which were still better than those in the IRI+PBS group (P < 0.05). The results suggest that BMSCs-EXO could attenuate lung IRI in rats, activate NF-κB pathway, and maintain mitochondrial stability by up-regulating miR-335.

Effect of intradiscal local anesthetic injection on intraoperative pain during percutaneous transforaminal endoscopic discectomy: A retrospective study.

OBJECTIVE: Patients undergoing percutaneous transforaminal endoscopic discectomy (PTED) often complain of unbearable intraoperative pain. This study is to observe clinical effectiveness and safety of intradiscal local anesthetic injection for intraoperative pain relief. METHODS: Total 268 patients who underwent PTED were analyzed. Patients were divided into intradiscal saline injection group (group C) and intradiscal local anesthetic injection group (group L). Intradiscal mixture was consisted of saline or local anesthetic + methylene blue, the amount of injected mixture was 3 mL. Demographic data, visual analog scale (VAS) and Quebec Back Pain Disability Scale (QBPDS) scores, mean arterial pressure (MAP) and heart rate (HR), total dosage of fentanyl, satisfaction rate of anesthesia and complications were collected at different timepoints. RESULTS: Compared with group C (3.94 ± 0.57), there was a significant reduction of VAS in group L (2.83 ± 0.28) during fibrous annular operation phase (T2). Group L had a lower total dosage of fentanyl (71 [63, 78] µg) and a higher anesthesia satisfaction rate (95.3%) than group C (82 [70, 132] µg and 73.6%, respectively) (P < 0.001). MAP and HR were lower in group L than in group C at T2 (P < 0.001). Baseline characteristics and QBPDS scores showed no meaningful intergroup differences. Four cases of complications were reported in this study. CONCLUSION: Intradiscal local anesthetic injection significantly alleviated intraoperative back pain and increased the satisfaction rate of anesthesia, without severe complications, indicating that this technique is a feasible method for intraoperative back pain relief for patients undergoing PTED.

Stability analysis of Hadamard and Caputo-Hadamard fractional nonlinear systems without and with delay.

This paper handles with the Hadamard and the Caputo-Hadamard fractional derivative and stability of related systems without and with delay. Firstly, the derivative inequalities are obtained, which is indispensable in applying the theorems derived in this paper. Then, for systems without delay, we get the stability results by using the Lyapunov direct method and for systems with delay, we explore two useful inequalities to verify the stability. Examples are presented with numerical simulations to illustrate the effectiveness of our results.

Hypercapnic acidosis confers antioxidant and anti-apoptosis effects against ventilator-induced lung injury.

Hypercapnic acidosis may attenuate ventilator-induced lung oxidative stress injury and alveolar cell apoptosis, but the underlying mechanisms are poorly understood. We examined the effects of hypercapnic acidosis on the role of apoptosis signal-regulating kinase 1 (ASK1), which activates the c-Jun N-terminal kinase (JNK) and p38 cascade in both apoptosis and oxidative reactions, in high-pressure ventilation stimulated rat lungs. Rats were ventilated with a peak inspiratory pressure (PIP) of 30 cmH2O for 4 h and randomly given FiCO2 to achieve normocapnia (PaCO2 at 35-45 mm Hg) or hypercapnia (PaCO2 at 80-100 mm Hg); normally ventilated rats with PIP of 15 cmH2O were used as controls. Lung injury was quantified by gas exchange, microvascular leaks, histology, levels of inflammatory cytokines, and pulmonary oxidative reactions. Apoptosis through the ASK1-JNK/p38 mitogen-activated protein kinase (MAPK) cascade in type II alveolar epithelial cells (AECIIs) were evaluated by examination of caspase-3 activation. The results showed that injurious ventilation caused significant lung injury, including deteriorative oxygenation, changes of histology, and the release of inflammatory cytokines. In addition, the high-pressure mechanical stretch also induced apoptosis and caspase-3 activation in the AECIIs. Hypercapnia attenuated these responses, suppressing the ASK1 signal pathways with its downstream kinase phosphorylation of p38 MAPK and JNK, and caspase-3 activation. Thus, hypercapnia can attenuate cell apoptosis and oxidative stress damage in rat lungs during injurious ventilation, at least in part, due to the suppression of the ASK1-JNK/p38 MAPK pathways.

[The effect of hydrogen on hemorrhagic shock induced acute lung injury in rats].

OBJECTIVE: To investigate the effect of hydrogen inhalation on acute lung injury after hemorrhagic shock in rats. METHODS: Twenty-four adult male Sprague-Dawley (SD) rats were equally randomized into three groups: sham operation group, model group and hydrogen-treatment group. Pressure-controlled hemorrhagic shock and resuscitation model was reproduced by blood-letting for 1 hour followed by fluid replacement for 2 hours. The rats in model group received a mixture of 50% oxygen-50% nitrogen during the process. The rats in hydrogen-treatment group received inhalation of a mixture of 2% hydrogen-48% nitrogen-50% oxygen 10 minutes before fluid replacement till the end of resuscitation. The arterial blood samples were collected for the measurement of arterial partial pressure of oxygen (PaO2) before exsanguination, 1 hour after shock, 1 hour and 2 hours after fluid replacement. Blood and lung tissues were collected at the end of experiment, and tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) levels in plasma, lung wet/dry weight ratio (W/D), malondialdehyde (MDA) content, superoxide dismutase (SOD) and myeloperoxidase (MPO) activity in the lung tissue were determined. The lung tissue was subjected to pathological examination. RESULTS: At the end of fluid replacement, compared with model group, hydrogen could significantly reduce pulmonary edema (lung W/D ratio: 4.72 ± 0.12 vs. 4.94 ± 0.14, P<0.05), inhibit oxidative stress (MDA: 0.55 ± 0.09 nmol/mg vs. 0.72 ± 0.08 nmol/mg, P<0.05), enhance antioxidant activity (SOD activity: 79.53 ± 14.33 U/mg vs. 59.55 ± 9.07 U/mg, P<0.05), reduce the release of pro-inflammatory cytokines (TNF-α: 55.58 ± 10.06 ng/L vs. 66.58 ± 5.17 ng/L; IL-6: 23.00 ± 2.77 ng/L vs. 27.09 ± 2.46 ng/L, both P<0.05) and inhibit neutrophil infiltration (MPO: 1.05 ± 0.18 U/g vs. 1.40 ± 0.14 U/g, P<0.05). It alleviated the damage to lung tissue, and then improved the lung function (PaO2: 146.3 ± 22.1 mm Hg vs. 123.6 ± 16.0 mm Hg, P<0.05). CONCLUSIONS: Hydrogen treatment can alleviate acute lung injury as a result of hemorrhagic shock and resuscitation.

Carbon monoxide inhalation ameliorates conditions of lung grafts from rat brain death donors.

BACKGROUND: Successful lung transplantation has been limited by the scarcity of donors. Brain death (BD) donors are major source of lung transplantation. Whereas BD process induces acute lung injury and aggravates lung ischemia reperfusion injury. Carbon monoxide (CO) inhalation at 50-500 parts per million (ppm) can ameliorate lung injury in several models. We examined in rats whether CO inhalation in BD donor would show favorable effects on lung grafts. METHODS: Rats were randomly divided into 4 groups. In sham group, donor rats received insertion of a balloon catheter into the cranial cavity, but the balloon was not inflated. In BD-only group, donor rats were ventilated with 40% oxygen after BD confirmation. In BD+CO250 and BD+CO500 groups, donor rats inhaled, after BD confirmation, 250 ppm or 500 ppm CO for 120 minutes prior to lung procurement, and orthotopic lung transplantation was performed. The rats were sacrificed 120 minutes after the lung transplantation by exsanguination, and their blood and lung graft samples were obtained. A total of 8 rats fulfilling the criteria were included in each group. RESULTS: The inhalation decreased the severity of lung injury in grafts from BD donors checked by histological examination. CO pretreatment reversed the aggravation of PaO2/FiO2 in recipients from BD donors. The CO inhalation down-regulated pro-inflammatory cytokines (TNF-alpha, IL-6) along with the increase of anti-inflammatory cytokine (IL-10) in recipient serum, and inhibited the activity of myeloperoxidase in grafts tissue. The inhalation significantly decreased cell apoptosis in lung grafts, inhibiting mRNA and protein expression of intercellular adhesion molecule-1 (ICAM-1) and caspase-3 in lung grafts. Further, the inhalation activated phosphorylation of p38 expression and inhibited phosphorylation of anti-extracellular signal-regulated kinase (ERK) expression in lung grafts. The effects of CO at 500 ppm were greater than those at 250 ppm. CONCLUSIONS: CO exerts potent protective effects on lung grafts from BD donor, exhibiting anti-inflammatory and anti-apoptosis functions by modulating the mitogen-activated protein kinase (MAPK) signal transduction.

Anti-apoptotic effect of morphine-induced delayed preconditioning on pulmonary artery endothelial cells with anoxia/reoxygenation injury.

BACKGROUND: Opioid preconditioning (PC) reduces anoxia/reoxygenation (A/R) injury to various cells. However, it remains unclear whether opioid-induced delayed PC would show anti-apoptotic effects on pulmonary artery endothelial cells (PAECs) suffering from A/R injury. The present study was conducted to elucidate this issue and to investigate the potential mechanism of opioid-induced delayed PC. METHODS: Cultured porcine PAECs underwent 16-hour anoxia followed by 1-hour reoxygenation 24 hours after pretreatment with saline (NaCl; 0.9%) or morphine (1 micromol/L). To determine the underlying mechanism, a non-selective K(ATP) channel inhibitor glibenclamide (Glib; 10 micromol/L), a nitric oxide (NO) synthase blocker NG-nitro-L-arginine methyl ester (L-NAME; 100 micromol/L), and an opioid receptor antagonist naloxone (Nal; 10 micromol/L) were given 30 minutes before the A/R load. The percentage of apoptotic cells was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining. eNOS mRNA level was measured by real-time polymerase chain reaction (PCR). NO content of PAECs supernatants was measured with the Griess reagent. RESULTS: Compared to the A/R PAECs, morphine-induced delayed PC significantly reduced PAECs apoptosis ((18.1 +/- 1.9)% vs (5.5 +/- 0.3)%; P < 0.05), increased NO release ((11.4 +/- 1.3) micromol/L vs (20.5 +/- 2.1) micromol/L, P < 0.05), and up-regulated eNOS gene expression nearly 9 times (P < 0.05). The anti-apoptosis effect of morphine was abolished by pretreatment with Glib, L-NAME and Nal, but the three agent-selves did not aggravate the A/R injury. Furthermore, L-NAME and Nal offset the enhanced release of NO caused by pretreatment with morphine. CONCLUSIONS: Morphine-induced delayed PC prevents A/R injury of PAECs. This effect may be mediated by activation of K(ATP) channel via opioid receptor and NO signaling pathways.