Diabetic neuropathic pain induced by streptozotocin alters the expression profile of non-coding RNAs in the spinal cord of mice as determined by sequencing analysis.

Diabetic neuropathic pain (DNP) is one of the most serious complications of diabetes. Patients with DNP always exhibit spontaneous and stimulus-evoked pain. However, the pathogenesis of DNP remains to be fully elucidated. Non-coding RNAs (ncRNAs) serve important roles in several cellular processes and dysregulated expression may result in the development of several diseases, including DNP. Although ncRNAs have been suggested to be involved in the pathogenesis of DNP, their precise roles remain to be determined. In the present study, sequencing analysis was used to investigate the expression patterns of coding genes, microRNAs (miRNAs), long ncRNAs (lncRNAs) and circular RNAs (circRNAs) in the spinal cord of mice with streptozotocin (STZ)-induced DNP. A total of 30 mRNAs, 148 miRNAs, 9 lncRNAs and 135 circRNAs exhibited significantly dysregulated expression 42 days after STZ injection. Functional enrichment analysis indicated that protein digestion and absorption pathways were the most significantly affected pathways of the differentially expressed (DE) mRNAs. The Rap1 signaling pathway, human T-lymphotropic virus-I infection and the MAPK signaling pathway were the three most significant pathways of the DE miRNAs. A total of 2,118 distinct circRNAs were identified and the length of the majority of the circRNAs was <1,000 nucleotides (nt) (1,552 circRNAs were >1,000 nt) with a median length of 620 nt. In the present study, the expression characteristics of coding genes, miRNAs, lncRNAs and circRNAs in DNP mice were determined; it paves the road for further studies on the mechanisms associated with DNP and potentially facilitates the discovery of novel ncRNAs for therapeutic targeting in the management of DNP.

[RhoA/Rho-kinase contributes to chronic pain following thoracotomy by up-regulating glutaminase 1 expression in rat spinal dorsal cord].

OBJECTIVE: To investigate whether RhoA/Rho-kinase contributes to the occurrence of chronic post-thoracotomy pain (CPSP) by up regulation of glutaminase 1 (GLS1) expression in the spinal dorsal cord. METHODS: Twenty five male Sprague Dawley (SD) rats were divided into control group (n=5) and model group (n=20). The rats in the model group were randomized into two sub groups (n=10) for observation on day 10 and day 21 after thoracotomy, and each group was further divided into CPSP and non CPSP groups according to the behavioral test results. All the rats were sacrificed after behavioral test for examination of GLS1 and RhoA expressions in the spinal cord using Western blotting and RT PCR. We also compared the effect of the Rho kinase inhibitor fasudil and saline, both injected intraperitoneally daily at 10 mg/kg for 7 consecutive days following thoracotomy, on CPSP and GLS1 expression in 30 male SD rats on day 21 after thoracotomy. RESULTS: Compared with the control group, the rats with CPSP showed significantly increased expressions of GLS1 and RhoA mRNA in the spinal cord on both day 10 and day 21 following thoracotomy (P<0.01), but the rats without CPSP did not show obvious changes in GLS1 and RhoA expressions. In fasudil treated rats, the mechanical pain threshold was obviously increased and the expressions of GLS1 and RhoA were significantly reduced as compared with those in saline treated rats (P<0.01). CONCLUSION: RhoA plays an important role in the occurence of CPSP by up-regulating the expression of GLS1 in the spinal dorsal cord of rats.

[Establishment of a modified rabbit model of acute lung injury induced by cardiopulmonary bypass].

OBJECTIVE: To establish an modified rabbit model of the acute lung injury induced by cardiopulmonary bypass (CPB) with ascending aorta and right atrium catheterization and detect the changes in serum tumor necrosis factor-α (TNF-α) level after modeling. METHODS: Ten healthy adult male New Zealand rabbits were randomly selected to establish CPB models. The model establishment was deemed successful if the rabbits survived for over 4 h with stable heart beat after termination of CPB. The vital signs of the rabbits were recorded after anesthesia (T1), before CPB (T2), at 15 after blocking the ascending aorta and pulmonary artery (T3), immediately after re-opening of the ascending aorta and pulmonary artery (T4), and at 1 (T5) and 4 (T6) after CPB. Arterial blood gas (ABG) was monitored at T2, T4 and T6 and the serum levels of TNF-α were also detected with ELISA. RESULTS: Nine rabbit models of CPB with acute lung injury were successfully established. During the operation, the MAP was maintained at a level above 55 mmHg, HCT significantly decreased from (30.18∓2.88)% at T2 to (17.73∓1.95)% at T4 (P<0.05), and plasma lactate level increased significantly from 3.65∓1.13 mmol/L at T2 to 9.36∓1.28 mmol/L at T4 (P<0.05). The oxygenation index (PaO2/FiO2) at T6 was significantly lower than that at T2 (281.64∓55.76 vs 468.36∓56.28 mmHg, P<0.05). The serum levels of TNF-α were significantly increased (P<0.05) and obvious lung interstitial edema and inflammatory cell infiltration occurred after CPB establishment. CONCLUSION: The modified rabbit model of CPB with acute lung injury is stable and reliable and can be used for studying acute lung injury induced by CPB.

Dexmedetomidine Protects Mouse Brain from Ischemia-Reperfusion Injury via Inhibiting Neuronal Autophagy through Up-Regulating HIF-1α.

Stroke is the leading cause of death in China and produces a heavy socio-economic burden in the past decades. Previous studies have shown that dexmedetomidine (DEX) is neuroprotective after cerebral ischemia. However, the role of autophagy during DEX-mediated neuroprotection after cerebral ischemia is still unknown. In this study, we found that post-conditioning with DEX and DEX+3-methyladenine (3-MA) (autophagy inhibitor) reduced brain infarct size and improved neurological deficits compared with DEX+RAPA (autophagy inducer) 24 h after transient middle cerebral artery artery occlusion (tMCAO) model in mice. DEX inhibited the neuronal autophagy in the peri-ischemic brain, and increased viability and decreased apoptosis of primary cultured neurons in oxygen-glucose deprivation (OGD) model. DEX induced expression of Bcl-1 and p62, while reduced the expression of microtubule-associated protein 1 light chain 3 (LC3) and Beclin 1 in primary cultured neurons through inhibition of apoptosis and autophagy. Meanwhile, DEX promoted the expression of hypoxia-inducible factor-1α (HIF-1α) both in vivo and in vitro, and 2-Methoxyestradiol (2ME2), an inhibitor of HIF-1α, could reverse DEX-induced autophagic inhibition. In conclusion, our study suggests that post-conditioning with DEX at the beginning of reperfusion protects mouse brain from ischemia-reperfusion injury via inhibition of neuronal autophagy by upregulation of HIF-1α, which provides a potential therapeutic treatment for acute ischemic injury.

Propofol up-regulates expression of ABCA1, ABCG1, and SR-B1 through the PPARγ/LXRα signaling pathway in THP-1 macrophage-derived foam cells.

BACKGROUND: ATP-binding cassette transporter A1 (ABCA1), ATP-binding cassette transporter G1 (ABCG1), and scavenger receptor-B1 (SR-B1) promote cholesterol efflux from cells to lipid-poor apolipoprotein A-I and play an important role in the development of atherosclerosis. Liver X receptor (LXRα) and peroxisome proliferator-activated receptor-gamma (PPARγ) operate as cholesterol sensors, which may protect from cholesterol overload by stimulating cholesterol efflux from cells to high-density lipoprotein through ABCA1, ABCG1, and SR-B1. Propofol administration is associated with cardiovascular protective effects, including anti-inflammatory and antioxidant properties. Here, we examined the effect of propofol on ABCA1, ABCG1, and SR-B1 expression and explored whether PPARγ and LXRα were involved in the regulation of propofol-induced ABCA1, ABCG1, and SR-B1 expression in THP-1 macrophage-derived foam cells. METHODS AND RESULTS: Propofol significantly increased expression levels of ABCA1, ABCG1, and SR-B1 in a time-dependent manner. Cellular cholesterol content was decreased while cholesterol efflux was increased by propofol treatment. Moreover, PPARγ and LXRα were up-regulated by propofol treatment. In addition, the up-regulated expression of ABCA1, ABCG1, and SR-B1 by propofol was significantly abolished by both PPARγ siRNA and LXRα siRNA in THP-1 macrophage-derived foam cells. CONCLUSION: These results provide evidence that propofol up-regulates expression of ABCA1, ABCG1, and SR-B1 through the PPARγ/LXRα pathway in THP-1 macrophage-derived foam cells.

Propofol Attenuates Lipopolysaccharide-Induced Monocyte Chemoattractant Protein-1 Production Through Enhancing apoM and foxa2 Expression in HepG2 Cells.

Monocyte chemoattractant protein-1 (MCP-1) is a cytokine that mediates the influx of cells to sites of inflammation. Our group recently reported that propofol exerted an anti-inflammatory effect and could inhibit lipopolysaccharide (LPS)-induced production of pro-inflammatory cytokines. However, the effect and possible mechanisms of propofol on MCP-1 expression remain unclear. LPS-stimulated HepG2 cells were treated with 50 µM propofol for 0, 6, 12, and 24 h, respectively. The transcript and protein levels were measured by real-time quantitative PCR and Western blot analyses, respectively. We found that propofol markedly decreased both MCP-1 messenger RNA (mRNA) and protein levels in LPS-stimulated HepG2 cells in a time-dependent manner. Expression of apolipoprotein M (apoM) and forkhead box protein A2 (foxa2) was increased by propofol treatment in HepG2 cells. In addition, the inhibitory effect of propofol on MCP-1 expression was significantly abolished by small interfering RNA against apoM and foxa2 in LPS-stimulated HepG2 cells. Propofol attenuates LPS-induced MCP-1 production through enhancing apoM and foxa2 expression in HepG2 cells.

[Effect of mean arterial pressure on arterial to end-tidal CO2partial pressure difference during one-lung ventilation].

OBJECTIVE: To study the effect of different mean arterial pressures (MAP) on arterial to end-tidal CO2partial pressure difference [(Pa-et)CO2] and the intrapulmonary shunt (Qs/Qt) in patients undergoing thoracic surgery during one-lung ventilation (OLV). METHODS: Forty-two patients undergoing right-sided pulmonary lobectomy were allocated into group A with fluctuation of MAP (at 20 min after OLV) within ± 10% of the baseline (n=22) and group B with lowered MAP by 30% of the baseline (n=20). Arterial and venous blood gas analyses were recorded to calculate [(Pa-et)CO2] and Qs/Qt at 20 min after induction with two-lung ventilation (T1), 20 min after OLV (T2), 30 min after recovery of normal blood pressure (T3), and 20 min after recovery of two-lung ventilation (T4). RESULTS: PetCO2and PaCO2were well correlated during two-lung ventilation and OLV in group A (P<0.05). In group B, [(Pa-et)CO2] at T2was significantly higher than that in group A, but PetCO2was still correlated with PaCO2(P<0.05). Qs/Qt increased more obviously in group B than in group A in T2(P<0.05). Bo obvious correlation was found between the [(Pa-et)CO2] and Qs/Qt during OLV. CONCLUSION: PetCO2reflects the dynamic changes of PaCO2under normal blood pressure during OLV. In the hypotension period, when [(Pa-et)CO2] increases and the correlation coefficient between PetCO2and PaCO2lowers, PetCO2may not accurately reflect the changes of PaCO2and blood gas analysis is warranted.

Propofol inhibits lipopolysaccharide-induced tumor necrosis factor-alpha expression and myocardial depression through decreasing the generation of superoxide anion in cardiomyocytes.

TNF-α has been shown to be a major factor responsible for myocardial depression in sepsis. The aim of this study was to investigate the effect of an anesthetic, propofol, on TNF-α expression in cardiomyocytes treated with LPS both in vivo and in vitro. In cultured cardiomyocytes, compared with control group, propofol significantly reduced protein expression of gp91phox and phosphorylation of extracellular regulated protein kinases 1/2 (ERK1/2) and p38 MAPK, which associates with reduced TNF-α production. In in vivo mice studies, propofol significantly improved myocardial depression and increased survival rate of mice after LPS treatment or during endotoxemia, which associates with reduced myocardial TNF-α production, gp91phox, ERK1/2, and p38 MAPK. It is concluded that propofol abrogates LPS-induced TNF-α production and alleviates cardiac depression through gp91phox/ERK1/2 or p38 MAPK signal pathway. These findings have great clinical importance in the application of propofol for patients enduring sepsis.

Effects of ulinastatin administered at different time points on the pathological morphologies of the lung tissues of rats with hyperthermia.

Hyperthermia not only directly induces cell injury of body tissues, but also causes the body to release large amounts of inflammatory mediators and cells with extensive biological activities to induce a systemic inflammatory response and immune dysfunction. Thus, hyperthermia causes systemic inflammatory response syndrome, aggravating injuries to various organs. This study aimed to observe the effects of ulinastatin (UTI) administered at different time points on the cellular morphologies of the lung tissues of rats with systemic hyperthermia. A total of 40 male Sprague Dawley rats were randomly divided into five groups: The normal control group (C group), the hyperthermia group without medication (H group), the hyperthermia and UTI pre-treatment group (HU group), the group treated with UTI at 1 h after hyperthermia (HU1 group), and the group treated with UTI at 2 h after hyperthermia (HU2 group). The systemic hyperthermia rat model was established in a heating chamber with a biological oxygen supply. For the HU, HU1 and HU2 groups, UTI (5×104 U/kg) was administered at different time points. For the C and H groups, an equivalent volume of normal saline was administered. During heating, the respiratory frequency and rectal temperature were measured and recorded once every 30 min. After 2.5 h of heating, the wet/dry weight (W/D) ratio of the lung tissues of the rats was measured. Additionally, the cellular morphologies of the lung tissues were observed under light and electron microscopes. The respiratory frequencies and lung tissue W/D ratios of the rats in the various hyperthermia groups were significantly higher than those of the rats in the C group (all P<0.05). The respiratory frequencies and lung tissue W/D values of the HU and HU1 groups were significantly lower than those of the H group (all P<0.05). Under the light microscope, the bronchial surrounding tissues of the HU and HU1 groups were loose, and the majority of the pulmonary alveolar structures were normal; the H and HU2 groups presented a number of changes, including pulmonary interstitial hyperemia, alveolar epithelial swelling and emphysema. Under the electron microscope, it was observed in the type II epithelial cells of the pulmonary alveoli of the H group that the mitochondria were swollen, the cell ridges were shortened, the microvilli were thin and increased, and the alveolar wall was thickened. Also, an increased number of infiltrating neutrophils were visible. In addition, the type II epithelial cells of the HU2 group also presented these changes to different extents and the changes in the HU and HU1 groups were the mildest. These results indicate that the early application of UTI relieves edema and the extent of cell injury of the lung tissue in rats with systemic hyperthermia.

[Prophylactic effect of acupuncture on nausea and vomiting after laparoscopic operation].

OBJECTIVE: To explore the prophylactic effect of acupuncture Neiguan (PC 6) on nausea and vomiting after laparoscopic operation. METHODS: One hundred patients with laparoscopic gastrointestinal operation were randomly divided into an acupuncture group and a control group, 50 patients in each group. The operation was carried out with the combined infusion and inhalation anesthesia. The patients in the acupuncture group were being punctured at bilateral Neiguan (PC 6) before anesthesia and during the operation. The needles were extracted after operation, and the acupoints were covered with opaque tape. In contrast, the patients in the control group only accepted tape covering without acupuncture. After operation, all patients were given the self-controlled intravenous analgesia, and followed up at 6 h, 12 h, 24 h, 48 h for recording the incidence rate of the nausea, retching and vomiting, then scoring with VAS. RESULTS: At 6 h, 12 h, 24 h, 48 h after operation, in the acupuncture group, the incidence rates of the nausea were 12.0%, 6.0%, 6.0% and 2.0%, and the incidence rates of the retching were 0, 0, 2.0% and 2.0%, respectively; in the control group, the incidence rates of the nausea were 28.0%, 20.0%, 12.0% and 2.0%, and the incidence rates of the retching were 2.0%, 6.0%, 2.0% and 0, respectively. At 6 h, 12 h after operation, the incidence rates of the nausea and retching in the acupuncture group were lower than those of the control group (P < 0.05, P < 0.001). The vomiting was not happened in both groups. There was no difference between the two groups according to the scoring with VAS. CONCLUSION: Acupuncturing at Neiguan (PC 6) can reduce the incidence rates of the patients' nausea and retching after laparoscopic operation, especially in 24 h.

[Changes of approximate entropy in rats during focal cerebral infarction].

OBJECTIVE: To investigate the changes of EEG approximate entropy (ApEn) in rats during focal cerebral infarction. METHODS: Twenty-four Sprague-Dawley (SD) rats were randomly divided into infarction group (n=12) with middle cerebral artery occlusion and sham-operated group (n=12). The EEG data (ApEn) was recorded in the bilateral areas (C3, C4) of the rats with focal cerebral infarction before the infarction and immediately and at 5, 15, 30, and 60 min after the infarction. The same measurement was carried out in the sham-operated group. RESULTS: In the sham-operated group, ApEn in C3 and C4 showed no obvious differences at the time points (P>0.05), but in the infarction group, ApEn in C3 and C4 increased significantly after the infarction. ApEn in the ischemic area (C4) was significantly lower than that in the non-ischemic area (C3) (P<0.05). The bilateral ApEn decreased with the passage of time. ApEn in the ischemic area (C4) was significantly lowered at 30 min after the infarction in comparison with that before infarction (P<0.05). In the sham-operated group, ApEn showed no significant difference between C3 and C4. ApEn was comparable between the two groups before the operation. CONCLUSION: ApEn can help monitor the occurrence of focal cerebral infarction of rats, and may be used to assess the extent of cerebral ischemia after infarction.

[Time window for intubation after rocuronium administration during target-controlled infusion of propofol and sulfentanil].

OBJECTIVE: To define the ideal time window for intubation after rocuronium administration during target-controlled infusion (TCI) ofpropofol and sulfentanil. METHODS: One hundred and twenty elective surgical patients (age range 18-55 years) were randomized into 4 groups (n=30) according to the intubation time after administration of the muscle relaxant. Patients with predicted difficult airway were excluded. General anesthesia was induced by TCI of propofol and sulfentanil. A senior anesthesiologist blinded for the randomization performed the intubations at 1, 2, 3, or 4 min after injection of rocuronium, and the vocal card visibility was evaluated upon full exposure of the vocal cord and the intubation conditions assessed according to Cooper's score. RESULTS: The intubation conditions were excellent or good in all patients, but the vocal cord visibility at 2-4 min differed significantly from that at 1 min after rocuronium administration (P<0.01). Suppression of the neuromuscular function 1 min after rocuronium administration differed significantly from that at other time points (P<0.01). CONCLUSION: The condition of vocal cord can be more suitable for intubation at 2-4 min than at 1 min after rocuronium administration as the ideal time window for intubation during TCI of propofol and sulfentanil.

Clinical efficacy of brachial plexus block with patient-controlled analgesia for postoperative analgesia and recovery in the antebrachium.

OBJECTIVE: To evaluate the analgesic effect of brachial plexus block using patient-controlled analgesia device after micro-surgery in the antebrachium and its impact on postoperative recovery. METHOD: Twenty-four patients (ASA class I or II ) scheduled for micro-surgery in the antebrachium under brachial plexus block were randomly divided into PCBPA group (n=12) with patient-controlled analgesia and control group (n=12) without postoperative analgesia. In PCBPA group, postoperative patient-controlled analgesia was implemented using the mixture of 1% lidocaine and 0.25% bupivacaine and a computer- based system (Graseby 9300) with basal infusion of 2 ml/h, bolus dose of 3 ml and lockout time of 45 min. Visual analogue scale (VAS) was adopted for the evaluation of the pain intensity in both groups within 72 h after surgery, and changes in the mean arterial pressure (MAP) and heart rate (HR) observed during the peri-operation period. RESULTS AND CONCLUSION: VAS, MAP and HR in PCBPA group were significantly lower than those in the control group ( P<0.05) within 24 h after surgery, suggesting the effectiveness of the analgesic modality using patient-controlled analgesia, which also inhibits postoperative stress reaction and promotes recovery following micro-surgery of the antebrachium.