Ventilator-induced lung injury (VILI) causes problems during acute lung injury treatment, and propofol is a well-known drug to prevent VILI. Herein, we discussed how propofol protects against VILI-induced inflammation with the interaction of nuclear factor E2-related factor 2 (Nrf2)/NOD-like receptor protein 3 (NLRP3). We established VILI mouse models for collecting lung tissues, and these mice were later treated with propofol and Nrf2/NLRP3 activator or inhibitor to observe their effects on VILI with inflammatory factors, 8-hydroxy-2 deoxyguanosine, malondialchehyche level, mitochondrial reactive oxygen species production rate, lung wet/dry weight ratio, lung permeability index measured. Propofol treatment improved VILI, alleviated pulmonary inflammation induced by mechanical ventilation. Propofol up-regulated Nrf2 and down-regulated NLRP3 in VILI model. Activating Nrf2 or inhibiting NLRP3 downregulated pro-inflammatory factors in lung tissues in VILI mice. Above all, we can conclude that propofol exerts it protective function against VILI and the subsequent inflammatory responses through activating Nrf2 and inhibiting NLRP3 expression. Therefore, Nrf2 activator and NLRP3 inhibitor might be latent targets in the VILI prevention.

Background: Morphine plays an irreplaceable role in relieving severe pain clinically, while long-term medication inevitably leads to drug resistance. MicroRNA (miR) 146a has been reported to be a negative regulator in the process of morphine-tolerance formation. This study aimed to investigate how miR-146a affects the development of morphine analgesic tolerance.Methods: The morphine-tolerance rat model was established by means of one-week continuous morphine administration. Paw withdrawal latency test was performed every day, and spinal cord samples were dissected on the seventh day for Q-PCR and Western blotting to detect the expression level of miR-146a, and IRAK1/TRAF6 participated in TLR4 signaling pathway.Results: The expression of miR-146 was significantly decreased in morphine-tolerant model. Also, overexpression of miR-146a reduced the resistance caused by morphine, followed by the down-regulation of IRAK1/TRAF6 in TLR4 pathway. The inhibition of miR-146a remarkably decreased paw withdrawal latency as well as increased the expression levels of TLR4 signaling pathway-related molecules, IRAK1 and TRAF6.Conclusion: This study suggests that miR-146a attenuates morphine tolerance by inhibiting the expression of IRAK1/TRAF6 in TLR4 pathway, which could provide an essential experimental basis for the settlement of morphine resistance-associated matters.

Background: Bupivacaine (BUP) acts as a local anesthetic, which is extensively used for clinical patients but could generate neurotoxicity in neurons. Tetramethylpyrazine (TET) exhibits strong neuron protective effects against neurotoxicity. Hence, we investigate the effect of TET on BUP-induced neurotoxicity in SH-SY5Y cells. Methods: CCK-8 assay was used to detect cell proliferation in SH-SY5Y cells. In addition, Western blotting was used to examine Bax, Bcl-2, active caspase 3, LC3II, Beclin 1 and p-62 protein levels in cells. Moreover, ELISA assay was used to detect the levels of total glutathione (GS), superoxide dismutase (SOD) and malondialdehyde (MDA) in cells. Results: In this study, we found that TET attenuated the neurotoxicity of BUP on SH-SY5Y cells. Meanwhile, TET alleviated BUP-induced apoptosis in SH-SY5Y cell via decreasing the expressions of active caspase-3 and Bax and increasing the expression of Bcl-2. In addition, monodansylcadaverine staining assay and Western blotting results confirmed that TET induced autophagy in SH-SY5Y cells via increasing the LC3II/I and Beclin 1 levels. Furthermore, TET attenuated BUP-induced oxidative damage in SH-SY5Y cells via upregulation of the levels of total GS and SOD and downregulation of the level of MDA. Interesting, the protective effects of TET against BUP-induced neurotoxicity in SH-SY5Y cells were reversed by autophagy inhibitor 3-methyladenine (3MA). Conclusion: These data indicated that TET may play a neuroprotective role via inhibiting apoptosis and inducing autophagy in SH-SY5Y cells. Therefore, TET may be a potential agent for the treatment of human neurotoxicity induced by BUP.

Background: Dexmedetomidine has been reported to play an efficient role on multi-organ protection. Our study aims to investigate the neuroprotective of dexmedetomidine preconditioning on cerebral ischemic reperfusion (I/R) injury and investigate the underlining signaling mechanisms.Methods: Cerebral I/R models were established with SD rats through middle cerebral artery occlusion (MCAO). After 2 h of ischemia followed by 7 days of reperfusion, the degree of cerebral tissue injury was detected by HE, Nissl and TUNEL staining. Glial fibrillary acidic protein (GFAP) positive and TNF-alpha positive cells were stained by immunohistochemistry and counted under microscope. TLR4, NF-kappa B and TIR-domain containing adapter-inducing interferon-beta (TRIF) expression were detected by real time PCR and western blot.Results: Dexmedetomidine preconditioning markedly prevented the ischemia-induced cellular damage observed from HE and Nissl staining in hippocampus and cortex. Dexmedetomidine observably decreased the number of apoptotic cells in TUNEL staining. Besides, yohimbine could specifically suppress the protective effect of dexmedetomidine. GFAP expression was distinctly inhibited by dexmedetomidine preconditioning (10 mu g/kg, 20 mu g/kg) in cerebral ischemia area. Dexmedetomidine preconditioning inhibited the expression of TLR4 and NF-kappa B and increased that of TRIF.Conclusion: The results of this study suggest that dexmedetomidine preconditioning plays a neuroprotective role against I/R injury. Dexmedetomidine might suppress TLR4/NF-??B pathway and drive TLR4/TRIF signaling pathway to reduce the inflammatory injury. (C) 2017 Elsevier Masson SAS. All rights reserved.