TAT-PEP Alleviated Cognitive Impairment by Alleviating Neuronal Mitochondria Damage and Apoptosis After Cerebral Ischemic Reperfusion Injury.

Paired immunoglobulin-like receptor B (PirB) was identified as a myelin-associated inhibitory protein (MAIP) receptor that plays a critical role in axonal regeneration, synaptic plasticity and neuronal survival after stroke. In our previous study, a transactivator of transcription-PirB extracellular peptide (TAT-PEP) was generated that can block the interactions between MAIs and PirB. We found that TAT-PEP treatment improved axonal regeneration, CST projection and long-term neurobehavioural recovery after stroke through its effects on PirB-mediated downstream signalling. However, the effect of TAT-PEP on the recovery of cognitive function and the survival of neurons also needs to be investigated. In this study, we investigated whether pirb RNAi could alleviate neuronal injury by inhibiting the expression of PirB following exposure to oxygen-glucose deprivation (OGD) in vitro. In addition, TAT-PEP treatment attenuated the volume of the brain infarct and promoted the recovery of neurobehavioural function and cognitive function. This study also found that TAT-PEP exerts neuroprotection by reducing neuronal degeneration and apoptosis after ischemia-reperfusion injury. In addition, TAT-PEP improved neuron survival and reduced lactate dehydrogenase (LDH) release in vitro. Results also showed that TAT-PEP reduced malondialdehyde (MDA) levels, increased superoxide dismutase (SOD) activity and reduced reactive oxygen species (ROS) accumulation in OGD-injured neurons. The possible mechanism was that TAT-PEP could contribute to the damage of neuronal mitochondria and affect the expression of cleaved caspase 3, Bax and Bcl-2. Our results suggest that PirB overexpression in neurons after ischaemic-reperfusion injury induces neuronal mitochondrial damage, oxidative stress and apoptosis. This study also suggests that TAT-PEP may be a potent neuroprotectant with therapeutic potential for stroke by reducing neuronal oxidative stress, mitochondrial damage, degeneration and apoptosis in ischemic stroke.

Ulinastatin attenuates lipopolysaccharide-induced cardiac dysfunction by inhibiting inflammation and regulating autophagy.

Ulinastatin exerts protective effects against lipopolysaccharide (LPS)-induced cardiac dysfunction. Autophagy has been demonstrated to serve an important role in sepsis-induced cardiomyopathy; however, whether ulinastatin has an anti-autophagic effect in sepsis requires further investigation. The present study aimed to determine the protective effects of ulinastatin on cardiac dysfunction and its role in autophagy during sepsis. C57BL/6J mice were randomly divided into a control, LPS and LPS + ulinastatin group, the survival status of the mice was observed every 6 h and the survival rate at each time point was calculated for 7 days. Furthermore, JC-1 dye and ELISAs were used to analyze the mitochondrial membrane potential (MMP) and serum cardiac troponin I (cTnI) levels, respectively. Western blotting and ELISAs were used to measure the levels of tumor necrosis factor (TNF)-α and interleukin (IL)-6. In addition, the cardiac ultrastructure and the number of autophagosomes formed were visualized using transmission electron microscopy, and the pathological changes in the myocardial tissues were analyzed using hematoxylin & eosin staining. Finally, the expression levels of autophagy-related proteins were analyzed using western blotting and immunofluorescence staining. The current study indicated that ulinastatin significantly improved the survival rate of septic mice. It was suggested that ulinastatin may protect against LPS-induced myocardium injury through its anti-inflammatory activity, as decreased cTnI levels, increased MMP and decreased expression levels of TNF-α and IL-6 were all observed following ulinastatin treatment. Furthermore, the number of autophagosomes formed, and the expression levels of microtubule-associated protein light chain 3 and Beclin 1 were significantly decreased following ulinastatin treatment. It was further observed that ulinastatin suppressed LPS-induced autophagosome formation, as indicated by the accumulation of sequestosome 1/p62, and the elimination of lysosome-associated membrane glycoprotein 1. In conclusion, the results of the present study suggested that ulinastatin treatment may improve survival and exert a protective effect over LPS-induced cardiac dysfunction. Furthermore, this protective effect may be associated with its anti-inflammatory and anti-autophagic activity.

Clinical Characteristics and Outcomes of Community-Acquired versus Hospital-Acquired Acute Kidney Injury: A Meta-Analysis.

BACKGROUND: The different clinical characteristics of community-acquired acute kidney injury (CA-AKI) versus hospital-acquired AKI (HA-AKI) have remained inconclusive, and thus, a meta-analysis was conducted to summarize and quantify the clinical significance distinguishing the 2 types of AKI. METHODS: We identified observational studies reporting the clinical characteristics and prognosis of HA-AKI and CA-AKI. ORs and mean differences (MDs) were extracted for each outcome and the results aggregated. The primary outcome was defined as the mortality rate; renal recovery, oliguria incidence, dialysis, intensive care unit (ICU) requirement, and length of hospital stay were secondary outcomes. RESULTS: Fifteen eligible studies involving 46,157 patients (22,791 CA-AKI patients and 23,366 HA-AKI patients) were included. Mortality was significantly lower in CA-AKI than in HA-AKI patients, with an OR of 0.43 (95% CI 0.35-0.53). The incidence of oliguria and need for ICU were also lower in CA-AKI patients (OR 0.58, 95% CI 0.38-0.88; OR 0.24, 95% CI 0.14-0.40, respectively). CA-AKI patients had a shorter hospital stay (MD -9.42, 95% CI -13.73 to -5.12). The renal recovery rate and dialysis need between CA- and HA-AKI were similar (OR 1.27, 95% CI 0.53-3.02; OR 1.05, 95% CI 0.82-1.34, respectively). CONCLUSIONS: CA-AKI showed better clinical manifestations with a lower incidence of oliguria, reduced risk of ICU treatment, and shorter hospital stay. Mortality associated with CA-AKI was lower compared with HA-AKI, indicating a better prognosis. The rate of renal recovery and need for dialysis showed no significant difference between the 2 groups.

Preconditioning with hydrogen sulfide ameliorates cerebral ischemia/reperfusion injury in a mouse model of transient middle cerebral artery occlusion.

Ischemic stroke and reperfusion injury are a common and serve medical situation in the elderly population. H2S is a gas neuromodulator which also possesses anti-oxidant and anti-inflammatory properties, and is found to play neuroprotective effect in neurodegenerative diseases. This study investigated the effect of endogenous and exogenous H2S in a mouse model of ischemic stroke. 129P2-Cbstm1Unc/J mice with heterozygous mutants in H2S generating enzyme cystathionine ß-synthase were used to study the effect of endogenous H2S. H2S donor NaHS was used as exogenous H2S. Animals were pretreated with H2S and then subjected to middle cerebral artery occlusion surgery. Behavioral outcome was evaluated by novel object recognition test. Inflammatory cytokines were measured using ELISA. Western blot was used to detect the activation of NF-κB. Aged 129P2-Cbstm1Unc/J mice showed exaggerated inflammation and more severe cognitive impairment after ischemia, while exogenous H2S treatment inhibited inflammation and attenuated behavioral impairment. The anti-inflammatory effect of H2S was mediated by inhibiting NF-κB. Our findings suggest that both endogenous and exogenous H2S are involved in the neuroprotection against ischemia/reperfusion-induced cerebral injury.

MiR-597 Targeting 14-3-3σ Enhances Cellular Invasion and EMT in Nasopharyngeal Carcinoma Cells.

BACKGROUND: Alterations in microRNAs (miRNAs) are related to the occurrence of nasopharyngeal carcinoma (NPC) and play an important role in the molecular mechanism of NPC. Our previous studies show low expression of 14-3-3σ (SFN) is related to the metastasis and differentiation of NPC, but the underlying molecular mechanisms remain unclear. METHODS: Through bioinformatics analysis, we find miR-597 is the preferred target miRNA of 14-3-3σ. The expression level of 14-3-3σ in NPC cell lines was detected by Western blotting. The expression of miR-597 in NPC cell lines was detected by qRT-PCR. We transfected miR-597 mimic, miR-597 inhibitor and 14-3-3σ siRNA into 6-10B cells and then verified the expression of 14-3-3σ and EMT related proteins, including E-cadherin, N-cadherin and Vimentin by western blotting. The changes of migration and invasion ability of NPC cell lines before and after transfected were determined by wound healing assay and Transwell assay. RESULTS: miR-597 expression was upregulated in NPC cell lines and repaired in related NPC cell lines, which exhibit a potent tumor-forming effect. After inhibiting the miR-597 expression, its effect on NPC cell line was obviously decreased. Moreover, 14-3-3σ acts as a tumor suppressor gene and its expression in NPC cell lines is negatively correlated with miR-597. Here 14-3-3σ was identified as a downstream target gene of miR-597, and its downregulation by miR-597 drives epithelial-mesenchymal transition (EMT) and promotes the migration and invasion of NPC. CONCLUSION: Based on these findings, our study will provide theoretical and experimental evidences for molecular targeted therapy of NPC.

Delta opioid receptor agonist attenuates lipopolysaccharide-induced myocardial injury by regulating autophagy.

BACKGROUND: Previous studies have described the protective effects of DADLE on myocardial injury in sepsis. Recently, autophagy has been shown to be an innate defense mechanism in sepsis-related myocardial injury. However, whether DADLE has an pro-autophagic effect is yet to be elucidated. The present study aimed to investigate the effect of DADLE on the regulation of autophagy during sepsis. METHODS: Male mice were subjected to LPS or vehicle intraperitoneal injection. After LPS injection, mice received either DADLE, Naltrindole or vehicle. ELISA and JC-1 were used to evaluate the level cTnI and Mitochondrial membrane potential. Cardiac ultrastructural and autophagosomes were visualized by transmission electron microscopy. The relative protein levels were analyzed by Western blot. RESULTS: The results showed that treatment with DADLE both immediately or 4 h after LPS intraperitoneal injection could improve the survival rate of mice with endotoxemic. DADLE could ease myocardium ultrastructure injury induced by LPS, this cardioprotective effect was also seen in increased MMP levels, and decreased cTnI levels. Through observation of transmission electron microscopy and Western blot we have discovered that the amount of autophagosome and the expression of autophagy related protein LC3II, Beclin1 were significantly increased with DADLE treatment. DADLE promoted LPS-induced autophagosome maturation as indicated by the increased LAMP-1 protein level and decreased SQSTM1/p62 protein level. The selective δ-opioid receptor antagonist Naltrindole play an opposite effects. CONCLUSIONS: DADLE could improve the survival and protect myocardial dysfunction in mice with LPS-induced endotoxemia. This effect was related to the increase of autophagy.

Crocin attenuates lipopolysacchride-induced acute lung injury in mice.

Crocin, a representative of carotenoid compounds, exerts a spectrum of activities including radical scavenger, anti-microbial and anti-inflammatory properties. To investigate the protective effect of crocin on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice. ALI was induced in mice by intratracheal instillation of LPS (1 mg/kg). The mice received intragastric injection of crocin (50 mg/kg) 1 h before LPS administration. Pulmonary histological changes were evaluated by hematoxylineosin stain and lung wet/dry weight ratios were observed. Concentrations of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß and nitric oxide (NO), and myeloperoxidase (MPO) activity were measured by enzymelinked immunosorbent assay. Expression of inducible nitric oxide synthase (iNOS) in lung tissues was determined by Western blot analysis. Crocin pretreatment significantly alleviated the severity of lung injury and inhibited the production of TNF-α and IL-1ß in mice with ALI. After LPS administration, the lung wet/dry weight ratios, as an index of lung edema, and MPO activity were also markedly reduced by crocin pretreatment. Crocin pretreatment also reduced the concentrations of NO in lung tissues. Furthermore, the expression of iNOS was significantly suppressed by crocin pretreatment. Croncin potently protected against LPS-induced ALI and the protective effects of crocin may attribute partly to the suppression of iNOS expression.

Protective role of isoflurane pretreatment in rats with focal cerebral ischemia and the underlying molecular mechanism.

Inflammation and immunity are important in the pathogenesis of cerebral ischemia. Toll-like receptor 4 (TLR4) is involved in the inflammatory responses of injured brain tissues. Emerging studies have focused on the effect of isoflurane (ISO) pretreatment on cerebral ischemia, however, the association between ISO pretreatment and TLR4 during cerebral ischemia remains to be elucidated. In the present study, the protective role of ISO pretreatment in rats with focal cerebral ischemia reperfusion was investigated and the molecular mechanism was discussed. Using a middle cerebral artery occlusion (MCAO) model, triphenyltetrazolium chloride staining was utilized to measure the infarct volume and brain edema and immunofluorescence staining was used to detect the MCAO-induced TLR4 expression and localization. Western blot analyses were conducted to quantify the protein expression levels of TLR4, myeloid differentiation primary response 88 (MyD88) and nuclear factor (NF)-κB in ischemic brain tissue at different time points. The results demonstrated that, following ISO pretreatment, the neurological deficits, brain edema and cerebral infarct size caused by ischemia/reperfusion were attenuated. The astrocyte and microglial activation in the brain tissue was decreased. In addition, the expression levels of TLR4, MyD88 and NF-κB were decreased. The present study indicated that ISO pretreatment may protect the brain from ischemic damage by downregulating the expression levels of TLR4, MyD88 and NF-κB.

Opioid δ(1) and δ(2) receptor agonist attenuate myocardial injury via mPTP in rats with acute hemorrhagic shock.

BACKGROUND: Studies have documented the beneficial roles of δ opioid receptor (OR) agonist for hemorrhagic shock. However, the myocardial protection roles and the mechanisms of hemodynamic stability during resuscitation of δ-OR agonist have not been explored. This study was designed to investigate myocardial protective effects and the mechanisms of high selective δ(1) and δ(2)-OR agonists during resuscitation of acute hemorrhagic shock. MATERIALS AND METHODS: Forty-eight adult male SD rats were adopted 60-min hemorrhagic shock through removing 30% (5 mL) of the total blood volume, and followed by 2-h resuscitation with shed blood and L-lactated Ringer's solution. At the end of shock and prior to resuscitation, NS, δ(1)-OR agonist TAN-67 (10 mg/kg) and antagonist BNTX (3 mg/kg), and BNTX+TAN-67, DMSO, δ(2)-OR agonist Deltorphin II (1 mg/kg) and antagonist NTB (2 mg/kg), and NTB+Deltorphin II in 0.5 mL were administrated. Left ventricular function parameters were measured during the whole experimental period. Myocardial mitochondria were isolated to determine opening of mitochondrial permeability transition pore (mPTP). Morphologic changes in myocardium and mitochondria were observed by electron microscope. RESULTS: The hemodynamic indexes in group TAN-67 and group Deltorphin II were higher than control group at each time point during resuscitation, respectively (P<0.05). TAN-67 and Deltorphin II decrease but their antagonists BNTX and NTB increase the opening of mPTP (P<0.05). Myocardial and mitochondrial damage were attenuated in group TAN-67 and group Deltorphin II. CONCLUSIONS: δ(1)-OR agonist TAN-67 and δ(2)-OR agonist Deltorphin II protect the heart by targeting the mPTP in rats with acute hemorrhagic shock.

Glycyrrhizin treatment is associated with attenuation of lipopolysaccharide-induced acute lung injury by inhibiting cyclooxygenase-2 and inducible nitric oxide synthase expression.

Glycyrrhizin (GL), a major active constituent of licorice root, has been attributed numerous pharmacologic effects, including anti-inflammatory, anti-viral, anti-tumor, and hepatoprotective activities. In this study, we investigated the anti-inflammatory effect of GL on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice. ALI was induced in Balb/c mice by intratracheal instillation of LPS (1 mg/kg). Before 1 h of LPS administration, the mice received intraperitoneal injection of GL at varied doses (10, 25, and 50 mg/kg). The severity of pulmonary injury was evaluated 12 h after LPS administration. GL pretreatment led to significant attenuation of LPS induced evident lung histopathologic changes, alveolar hemorrhage, and neutrophil infiltration with evidence of reduced myeloperoxidase (MPO) activity. The lung wet/dry weight ratios, as an index of lung edema, were markedly reduced by GL pretreatment. The concentrations of pro-inflammatory cytokines interleukin (IL)-1ß and tumor necrosis factor (TNF)-α were elevated in bronchoalveolar lavage fluid (BALF) after LPS administration, which were significantly inhibited by GL pretreatment. GL pretreatment also reduced the concentrations of nitric oxide (NO) in lung tissues. Furthermore, the expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) was suppressed by GL pretreatment. In conclusion, GL potently protected against LPS-induced ALI, and the protective effects of GL may attribute partly to the suppression of COX-2 and iNOS expression.

The effects of intravenous hyperoxygenated solution infusion on systemic oxygenation and intrapulmonary shunt during one-lung ventilation in pigs.

BACKGROUND: Many anesthetic methods have been applied to maintain acceptable oxygenation during one-lung ventilation (OLV). However, the optimal management has not been definitely determined. The aim of this study was to investigate whether intravenous hyperoxygenated solution (HOS) infusion would improve systemic oxygenation and reduce intrapulmonary shunt during OLV. MATERIALS AND METHODS: Sixteen pigs (25-35 kg) were anesthetized, tracheally intubated, and mechanically ventilated. After placement of femoral artery and pulmonary artery catheters, a left-sided double-lumen tube (DLT) was placed via tracheotomy. The animals were allocated randomly to one of the two study groups (n = 8 each); control group (C group) and hyperoxygenated solution group (H group). Animals in H group received intravenous HOS infusion immediately after the beginning of OLV via internal right jugular vein with an infusion pump, and the rate of infusion was 15 mL.kg(-l).h(-l); and in C group, the same amount of lactate Ringer's solution (LRS) was used in place of HOS. Arterial and venous blood gases analysis were recorded in three phases: during two-lung ventilation just before beginning OLV (TLV), 30 min after beginning OLV (OLV + 30), and 60 min after beginning OLV (OLV + 60). We measured arterial oxygen saturation (SaO(2)), mixing venous oxygen saturation (S(V)O(2)), partial pressure of arterial oxygen (PaO(2)), partial pressure of mixing venous oxygen (PvO(2),) oxygen contents in systemic arterial and mixed venous blood (CaO(2), CvO(2)), and venous admixture percentage (Qs/Qt%). Heart rate (HR), mean arterial pressure (MAP), mean pulmonary artery pressure (MPAP), and cardiac output (CO) were also recorded. RESULTS: After 30 and 60 min OLV, there was a significant decrease in PaO(2), SaO(2), PvO(2), SvO(2), CaO(2), and CvO(2), and a significant increase of Qs/Qt% in both groups (P < 0.01). The values of PaO(2), SaO(2), PvO(2), SvO(2), and CvO(2) in H group at both OLV + 30 and OLV + 60 were significantly higher than those in C group (P < 0.05, P < 0.01). Although the values of CaO(2) in H group were higher than those in C group at OLV + 30 and OLV + 60, there were no significant differences. Comparing the values of Qs/Qt% between the two groups at OLV + 30 and OLV + 60, there were also no significant differences. CONCLUSIONS: Intravenous HOS infusion led to minimal changes in intrapulmonary shunt, nevertheless, it could ameliorate arterial oxygenation obviously during OLV. This might be a new strategy to improve systemic oxygenation during OLV.

Pretreatment with fentanyl and propofol attenuates myocardial injury in rabbits with acute hemorrhagic shock.

BACKGROUND: Many studies have shown that preconditioning with anesthetics can be used to simulate the myocardial protective effects of ischemic preconditioning. But it is still not certain whether they can protect the myocardium in hemorrhagic shock. This study was designed to examine the myocardial protective effects of propofol and fentanyl in acute hemorrhagic shock. MATERIALS AND METHODS: Thirty-six white rabbits were randomly divided into a control group (group C), propofol preconditioning group (group P), and fentanyl preconditioning group (group F). The animal model of acute hemorrhagic shock was established according to Wigger's method. The same volumes of saline, propofol (5 mg/kg), or fentanyl (25 microg/kg) were administered 15 min before bleeding. Left ventricular function parameters were monitored continuously during 90 min of hemorrhagic shock. Serum cardiac troponin I (cTn-I) was detected by chemiluminescence before bleeding and 60 and 90 min after bleeding. Myocardial samples were taken for morphological studies. RESULTS: Compared with group C, the hemodynamic indexes in group F and group P were higher at each time point of shock (P < 0.05). The cTn-I values in group P and group F were lower than in group C (P < 0.05). Electron microscopic examination of the myocardium indicated that the alterations of myocardial structure and mitochondria were less pronounced in both group F and group P. CONCLUSIONS: Propofol and fentanyl preconditioning can protect the heart against acute ischemia and promote the recovery of hemodynamics during hemorrhagic shock.