HSV-1 reactivation results in post-herpetic neuralgia by upregulating Prmt6 and inhibiting cGAS-STING.

Chronic varicella zoster virus (VZV) infection induced neuroinflammatory condition is the critical pathology of post-herpetic neuralgia (PHN). The immune escape mechanism of VZV remains elusive. As to mice have no VZV infection receptor, herpes simplex virus type 1 (HSV-1) infection is a well established PHN mice model. Transcriptional expression analysis identified that the protein arginine methyltransferases 6 (Prmt6) was upregulated upon HSV-1 infection, which was further confirmed by immunofluorescence staining in spinal dorsal horn. Prmt6 deficiency decreased HSV-1-induced neuroinflammation and PHN by enhancing antiviral innate immunity and decreasing HSV-1 load in vivo and in vitro. Overexpression of Prmt6 in microglia dampened antiviral innate immunity and increased HSV-1 load. Mechanistically, Prmt6 methylated and inactivated STING, resulting in reduced phosphorylation of TANK binding kinase-1 (TBK1) and interferon regulatory factor 3 (IRF3), diminished production of type I interferon (IFN-I) and antiviral innate immunity. Furthermore, intrathecal or intraperitoneal administration of the Prmt6 inhibitor EPZ020411 decreased HSV-1-induced neuroinflammation and PHN by enhancing antiviral innate immunity and decreasing HSV-1 load. Our findings revealed that HSV-1 escapes antiviral innate immunity and results in PHN by upregulating Prmt6 expression and inhibiting the cGAS-STING pathway, providing novel insights and a potential therapeutic target for PHN.

PRMT6 deficiency or inhibition alleviates neuropathic pain by decreasing glycolysis and inflammation in microglia.

Microglia induced chronic inflammation is the critical pathology of Neuropathic pain (NP). Metabolic reprogramming of macrophage has been intensively reported in various chronic inflammation diseases. However, the metabolic reprogramming of microglia in chronic pain remains to be elusive. Here, we reported that immuno-metabolic markers (HIF-1α, PKM2, GLUT1 and lactate) were related with increased expression of PRMT6 in the ipsilateral spinal cord dorsal horn of the chronic construction injury (CCI) mice. PRMT6 deficiency or prophylactic and therapeutic intrathecal administration of PRMT6 inhibitor (EPZ020411) ameliorated CCI-induced NP, inflammation and glycolysis in the ipsilateral spinal cord dorsal horn. PRMT6 knockout or knockdown inhibited LPS-induced inflammation, proliferation and glycolysis in microglia cells. While PRMT6 overexpression exacerbated LPS-induced inflammation, proliferation and glycolysis in BV2 cells. Recent research revealed that PRMT6 could interact with and methylate HIF-1α, which increased HIF-1α protein stability. In sum, increased expression of PRMT6 exacerbates NP progress by increasing glycolysis and neuroinflammation through interacting with and stabilizing HIF-1α in a methyltransferase manner, which outlines novel pathological mechanism and drug target for NP.

Inhibition of Sirt3 activates the cGAS-STING pathway to aggravate hepatocyte damage in hepatic ischemia-reperfusion injury mice.

Hepatic ischemia-reperfusion injury (IRI) typically manifests during subtotal hepatectomy and inflicts substantial damage to liver function in the perioperative period. Although the central role of cGAS-STING-mediated immune inflammation in hepatocyte damage during hepatic IRI is acknowledged, the precise regulatory mechanisms remain elusive. The current study aims to elucidate how Sirt3 inhibition activates the cGAS-STING pathway and exacerbates hepatocyte damage in hepatic IRI. We established both in vivo and in vitro models by creating hepatic IRI mice model and subjecting AML-12 hepatocyte cell lines to oxygen-glucose deprivation/reperfusion (OGD/R). Hepatic IRI compromised liver and mitochondrial function while elevating cytosolic mitochondrial DNA (mtDNA) levels in hepatocytes. Additionally, both in vivo hepatic IRI and in vitro OGD/R induced increased phosphorylation and activation of cGAS, STING, and IRF3, accompanied by heightened levels of pro-inflammatory factors, including TNF-α, IL-1ß, and type I interferon (IFN-ß). Importantly, knockdown of cGAS or STING through siRNA effectively attenuated hepatic IRI-induced inflammation and ameliorated liver function in both experimental settings, underscoring the dynamic involvement of the cGAS-STING pathway in hepatic IRI-induced inflammation. Furthermore, we observed a significant reduction in Sirt3 expression following hepatic IRI, both in vivo and in vitro. Then we generated Sirt3-deficient mice and applied Sirt3 knockdown in AML-12 hepatocytes. Notably, Sirt3 deficiency led to increased phosphorylation and activation of cGAS, STING, and IRF3, coupled with elevated TNF-α, IL-1ß, and IFN-ß levels in both in vivo and in vitro conditions. Moreover, upon silencing various downstream targets of Sirt3, such as transcription factors Sp1, Pu1, and p65, we observed that specifically knocking down p65 in AML-12 hepatocytes reduced cGAS mRNA levels. Co-immunoprecipitation assays confirmed a direct interaction between Sirt3 and p65. The absence of Sirt3 significantly increased nuclear translocation of p65 in mice, whereas Sirt3 knockdown in AML-12 hepatocytes heightened nuclear translocation of p65. ChIP-PCR assays demonstrated that Sirt3 deficiency notably enhanced the binding of p65 to two cGAS promoters, ultimately promoting cGAS transcription. Collectively, our results underscored that inhibition of Sirt3 activates the cGAS-STING pathway to aggravate hepatocyte damage by increasing cytosolic mtDNA and promoting nuclear translocation of p65 to promote cGAS transcription in hepatic IRI. These findings hold promise for potential therapeutic interventions in hepatic IRI by targeting the Sirt3-cGAS-STING axis, offering new avenues for the development of clinical strategies to mitigate liver damage during the perioperative period.

Microglial exosome miR-124-3p in hippocampus alleviates cognitive impairment induced by postoperative pain in elderly mice.

Cognitive impairment induced by postoperative pain severely deteriorates the rehabilitation outcomes in elderly patients. The present study focused on the relationship between microglial exosome miR-124-3p in hippocampus and cognitive impairment induced by postoperative pain. Cognitive impairment model induced by postoperative pain was constructed by intramedullary nail fixation after tibial fracture. Morphine intraperitoneally was carried out for postoperative analgesia. Morris water maze tests were carried out to evaluate the cognitive impairment, while mRNA levels of neurotrophic factors (BDNF, NG) and neurodegenerative biomarker (VILIP-1) in hippocampus were tested by q-PCR. Transmission electron microscope was used to observe the axon degeneration in hippocampus. The levels of pro-inflammatory factors (TNF-α, IL-1ß, IL-6), the levels of anti-inflammatory factors (Ym, Arg-1, IL-10) and microglia proliferation marker cyclin D1 in hippocampus were measured to evaluate microglia polarization. Bioinformatics analysis was conducted to identify key exosomes while BV-2 microglia overexpressing exosome miR-124-3p was constructed to observe microglia polarization in vitro experiments. Exogenous miR-124-3p-loaded exosomes were injected into hippocampus in vivo. Postoperative pain induced by intramedullary fixation after tibial fracture was confirmed by decreased mechanical and thermal pain thresholds. Postoperative pain induced cognitive impairment, promoted axon demyelination, decreased BDNF, NG and increased VILIP-1 expressions in hippocampus. Postoperative pain also increased pro-inflammatory factors, cyclin D1 and decreased anti-inflammatory factors in hippocampus. However, these changes were all reversed by morphine analgesia. Bioinformatics analysis identified the critical role of exosome miR-124-3p in cognitive impairment, which was confirmed to be down-regulated in hippocampus of postoperative pain mice. BV-2 microglia overexpressing exosome miR-124-3p showed decreased pro-inflammatory factors, cyclin D1 and increased anti-inflammatory factors. In vivo, stereotactic injection of exogenous miR-124-3p into hippocampus decreased pro-inflammatory factors, cyclin D1 and increased anti-inflammatory factors. The cognitive impairment, axon demyelination, decreased BDNF, NG and increased VILIP-1 expressions in hippocampus were all alleviated by exogenous exosome miR-124-3p. Microglial exosome miR-124-3p in hippocampus alleviates cognitive impairment induced by postoperative pain through microglia polarization in elderly mice.

Ischemic preconditioning attenuates endoplasmic reticulum stress-dependent apoptosis of hepatocytes by regulating autophagy in hepatic ischemia-reperfusion injury.

Hepatic ischemia-reperfusion injury (HIRI) usually occurs during subtotal hepatectomy and severely damages liver function during the perioperative period. Endoplasmic reticulum stress (ERS) dependent apoptosis has been suggested to play a crucial role in HIRI progression. The present study focused on the regulatory effect of autophagy activation induced by ischemic preconditioning (IPC) on ERS-dependent apoptosis of hepatocytes in HIRI. A HIRI mouse model and oxygen-glucose deprivation/reperfusion (OGD/R) AML-12 hepatocyte cell lines were constructed to evaluate the protective effect of IPC in vivo and in vitro. The protein levels of p-eIF2α, CHOP, and cleaved caspase-12 were used to evaluate the ERS-dependent apoptosis, whereas LC3-II and p62 were considered as the autophagy activation markers. The beneficial molecular chaperones GRP78, HSP60, and HSP70 were also tested to evaluate autophagy. HIRI significantly increased ERS-dependent apoptosis markers and the number of apoptotic cells and damaged liver function. The ERS inhibitor salubrinal significantly alleviated liver injury in HIRI and OGD/R hepatocytes. Furthermore, both remote IPC and direct IPC significantly alleviated liver injury and inflammatory cell infiltration. IPC also upregulated LC3-II, downregulated p62 expression, and increased the mRNA levels of GRP78, HSP60, and HSP70 in HIRI mice and OGD/R hepatocytes, indicating the activation of autophagy by IPC. The autophagy inhibitor 3-methyladenine significantly attenuated the protective effects of IPC on ERS-dependent apoptosis and liver function, whereas the autophagy activator rapamycin mimicked the protective effects of IPC on ERS-dependent apoptosis in vivo and in vitro, suggesting a regulatory role of autophagy in ERS-dependent apoptosis. These results demonstrated that IPC could induce moderate autophagy and upregulate a few molecular chaperones to strengthen endogenous defense mechanisms, which is beneficial for alleviating ERS-dependent apoptosis and protecting hepatocytes from HIRI.

Lyn-mediated glycolysis enhancement of microglia contributes to neuropathic pain through facilitating IRF5 nuclear translocation in spinal dorsal horn.

The pro-inflammatory phenotype of microglia usually induces neuroinflammatory reactions in neuropathic pain. Glycometabolism shift to glycolysis can promote the pro-inflammatory phenotype transition of microglia. The omics data analysis suggest a critical role for Lyn dysregulation in neuropathic pain. The present study aimed at exploring the mechanism of Lyn-mediated glycolysis enhancement of microglia in neuropathic pain. Neuropathic pain model was established by chronic constriction injury (CCI), then pain thresholds and Lyn expression were measured. Lyn inhibitor Bafetinib and siRNA-lyn knockdown were administrated intrathecally to evaluate the effects of Lyn on pain thresholds, glycolysis and interferon regulatory factor 5 (IRF5) nuclear translocation of microglia in vivo and in vitro. ChIP was carried out to observe the binding of transcription factors SP1, PU.1 to glycolytic gene promoters by IRF5 knockdown. Finally, the relationship between glycolysis and pro-inflammatory phenotype transition of microglia was evaluated. CCI led to the upregulation of Lyn expression and glycolysis enhancement in microglia of spinal dorsal horn. Bafetinib or siRNA-lyn knockdown intrathecally alleviated pain hyperalgesia, suppressed glycolysis enhancement and inhibited nuclear translocation of IRF5 in CCI mice. Also, IRF5 promoted the binding of transcription factors SP1, PU.1 to glycolytic gene promoters, and then the enhanced glycolysis facilitated the proliferation and pro-inflammatory phenotype transition of microglia and contributed to neuropathic pain. Lyn-mediated glycolysis enhancement of microglia contributes to neuropathic pain through facilitating IRF5 nuclear translocation in spinal dorsal horn.

Protective Efficiency Comparison of Direct and Remote Ischemic Preconditioning on Ischemia Reperfusion Injury of the Liver in Patients Undergoing Partial Hepatectomy.

Objective: Ischemia reperfusion injury greatly damages liver function and deteriorates the prognosis of patients undergoing partial hepatectomy. This study is to compare the protective efficiency of direct and remote ischemic preconditioning (DIPC and RIPC) on ischemia reperfusion injury of the liver in patients undergoing partial hepatectomy. Methods: 90 patients scheduled for partial hepatectomy were enrolled and randomly divided into control (n = 30), DIPC (n = 30), and RIPC (n = 30) groups. Baseline and surgery characteristics were collected, and ischemic preconditioning methods were carried out. Intraoperative hemodynamics, liver function and liver reserve capacity, oxidative stress, and inflammatory responses were measured, and the incidence of postoperative adverse reactions was calculated finally. Results: 10 patients were excluded from the study, and finally, the eligible patients in three groups were 27, 28, and 25, separately. No significant differences were observed in baseline and surgery characteristics among the three groups. SBP and DBP were significantly higher after hepatic portal vein occlusion while they were significantly lower after surgery in the DIPC and RIPC groups compared with that in the control group, SBP and DBP were of great fluctuation at different time points in the control group while they showed much more stabilization in the DIPC and RIPC groups. ALT, AST, and TBIL were significantly decreased on days 1, 3, and 5 after surgery, and ICG R15 was significantly decreased while ICG K value and EHBF were significantly increased on day 1 after surgery in the DIPC and RIPC groups compared with that in the control group. Moreover, antioxidant enzyme SOD was increased, and inflammatory factors TNF-α and IL-1ß were decreased 24 hours after surgery in the DIPC and RIPC groups compared with that in the control group. DIPC and RIPC also decreased hospital stays and the incidence of nausea, vomiting, and hypertension. Conclusion: DIPC and RIPC both alleviated ischemia reperfusion injury of the liver and reduced perioperative complications with similar protective efficiency in patients undergoing partial hepatectomy.

Huc-MSCs-derived exosomes attenuate inflammatory pain by regulating microglia pyroptosis and autophagy via the miR-146a-5p/TRAF6 axis.

BACKGROUND: Chronic inflammatory pain significantly reduces the quality of life and lacks effective interventions. In recent years, human umbilical cord mesenchymal stem cells (huc-MSCs)-derived exosomes have been used to relieve neuropathic pain and other inflammatory diseases as a promising cell-free therapeutic strategy. However, the therapeutic value of huc-MSCs-derived exosomes in complete Freund's adjuvant (CFA)-induced inflammatory pain remains to be confirmed. In this study, we investigated the therapeutic effect and related mechanisms of huc-MSCs-derived exosomes in a chronic inflammatory pain model. METHODS: C57BL/6J male mice were used to establish a CFA-induced inflammatory pain model, and huc-MSCs-derived exosomes were intrathecally injected for 4 consecutive days. BV2 microglia cells were stimulated with lipopolysaccharide (LPS) plus adenosine triphosphate (ATP) to investigate the effect of huc-MSCs-derived exosomes on pyroptosis and autophagy. Bioinformatic analysis and rescue experiments were used to demonstrate the role of miR-146a-5p/ TRAF6 in regulating pyroptosis and autophagy. Western blotting, RT-qPCR, small interfering RNA and Yo-Pro-1 dye staining were performed to investigate the related mechanisms. RESULTS: Huc-MSCs-derived exosomes alleviated mechanical allodynia and thermal hyperalgesia in CFA-induced inflammatory pain. Furthermore, huc-MSCs-derived exosomes attenuated neuroinflammation by increasing the expression of autophagy-related proteins (LC3-II and beclin1) and inhibiting the activation of NLRP3 inflammasomes in the spinal cord dorsal horn. In vitro, NLRP3 inflammasome components (NLRP3, caspase1-p20, ASC) and gasdermin D (GSDMD-F, GSDMD-N) were inhibited in BV2 cells pretreated with huc-MSCs-derived exosomes. Western blot and Yo-Pro-1 dye staining demonstrated that 3-MA, an autophagy inhibitor, weakened the protective effect of huc-MSCs-derived exosomes on BV2 cell pyroptosis. Importantly, huc-MSCs-derived exosomes transfected with miR-146a-5p mimic promoted autophagy and inhibited BV2 cell pyroptosis. TRAF6, as a target gene of miR-146a-5p, was knocked down via small-interfering RNA, which increased pyroptosis and inhibited autophagy. CONCLUSION: Huc-MSCs-derived exosomes attenuated inflammatory pain via miR-146a-5p/TRAF6, which increased the level of autophagy and inhibited pyroptosis.

Glycometabolism Reprogramming of Glial Cells in Central Nervous System: Novel Target for Neuropathic Pain.

Neuropathic pain is characterized by hyperalgesia and allodynia. Inflammatory response is conducive to tissue recovery upon nerve injury, but persistent and exaggerated inflammation is detrimental and participates in neuropathic pain. Synaptic transmission in the nociceptive pathway, and particularly the balance between facilitation and inhibition, could be affected by inflammation, which in turn is regulated by glial cells. Importantly, glycometabolism exerts a vital role in the inflammatory process. Glycometabolism reprogramming of inflammatory cells in neuropathic pain is characterized by impaired oxidative phosphorylation in mitochondria and enhanced glycolysis. These changes induce phenotypic transition of inflammatory cells to promote neural inflammation and oxidative stress in peripheral and central nervous system. Accumulation of lactate in synaptic microenvironment also contributes to synaptic remodeling and central sensitization. Previous studies mainly focused on the glycometabolism reprogramming in peripheral inflammatory cells such as macrophage or lymphocyte, little attention was paid to the regulation effects of glycometabolism reprogramming on the inflammatory responses in glial cells. This review summarizes the evidences for glycometabolism reprogramming in peripheral inflammatory cells, and presents a small quantity of present studies on glycometabolism in glial cells, expecting to promote the exploration in glycometabolism in glial cells of neuropathic pain.

Efficacy Assessment of Phentolamine Accompanied by Lidocaine Subcutaneously under Ultrasound Guidance on Radial Artery Catheterization in Pediatric Patients.

Objective: Pediatric patients are facing greater difficulties in radial catheterization for anatomic variation and smaller diameter. This study is to investigate the efficacy of phentolamine accompanied by lidocaine subcutaneously under ultrasound guidance on radial catheterization in pediatric patients. Methods: 66 pediatric patients were enrolled and randomly divided into saline group, phentolamine group, and phentolamine+lidocaine group. Baseline characteristics and surgical types were collected. Relevant solutions were subcutaneously injected, and catheterization was subsequently conducted under ultrasound guidance. Radial artery diameter and depth were measured, the success rate of catheterization and procedure time were calculated, and the complications were evaluated with ultrasonography. Results: No significant differences were observed in age, sex, weight, American Society of Anesthesiologists' classification, systolic blood pressure, diastolic blood pressure, heart rate, hemoglobin, and surgical types among three groups. Subcutaneously, the diameter in phentolamine and phentolamine+lidocaine groups increased significantly compared with the saline group. Moreover, the diameter also increased significantly after injection compared with that before injection both in the phentolamine and phentolamine+lidocaine groups. The first-attempt success rates were significantly higher while the procedure times of cannulation were shorter in the phentolamine and phentolamine+lidocaine groups than that in the saline group. Kaplan-Meier analysis showed that the overall procedure time was shorter in the phentolamine and phentolamine+lidocaine groups than the saline group. Overall complications and vasospasm incidence were lower in the phentolamine and phentolamine+lidocaine groups than the saline group. Conclusion: Phentolamine accompanied by lidocaine subcutaneous injection under ultrasound guidance improved the first-attempt success rate and reduced the complication of radial artery catheterization in pediatric patients.

BRD4 Inhibition Attenuates Inflammatory Pain by Ameliorating NLRP3 Inflammasome-Induced Pyroptosis.

Chronic pain, such as persistent inflammatory pain, remains a public health problem that has no effective treatment at present. Bromodomain-containing protein 4 (BRD4) inhibition, induced by JQ1 injection or BRD4 knockdown, has been used to attenuate inflammatory pain; However, it remains elusive whether BRD4 aggravates inflammatory pain by regulating inflammasome. Western blot and immunofluorescence staining showed that BRD4 expression increased after administration of complete Freund's adjuvant (CFA) and reached its peak on day 3. Immunofluorescence staining showed that BRD4 was mainly colocalized with NeuN-positive neurons in the spinal cord, which was accompanied by upregulation of inflammasome component proteins, such as NLRP3, gasdermin D, and caspase-1. JQ1 was intrathecally injected into mice 1 h before CFA administration, and the mechanical and thermal hyperalgesia levels were measured on days 1, 3, and 7 after CFA administration. CFA-induced inflammatory pain, paw inflammation, and swelling were attenuated by pre-treatment with JQ1. To our knowledge, this study was the first to prove that NLRP3 inflammasome-induced neuronal pyroptosis participates in inflammatory pain. BRD4 inhibition decreased the expression of pyroptosis-related proteins by inhibiting the activation of NF-κB signaling pathway, both in vivo and in vitro. Taken together, BRD4 inhibition exerted analgesic and anti-inflammatory effects against inflammatory pain by inhibiting NF-κB and inflammasome activation, which protected neural cells from pyroptosis.

Bilirubin Induces Pain Desensitization in Cholestasis by Activating 5-Hydroxytryptamine 3A Receptor in Spinal Cord.

BACKGROUND: Cholestasis patients often suffer from pain desensitization, resulting in serious complications in perioperative period. This study was aim to investigate the mechanism of bilirubin in cholestasis mediating pain desensitization through 5-hydroxytryptamine 3A (5-HT3A ) receptor activation in spinal dorsal horn (SDH). METHODS: A cholestasis model was established by bile duct ligation (BDL) in rats. Pain thresholds of rats were measured after BDL or intrathecally injecting bilirubin in the presence or absence of agonist (mCPBG) and antagonists (ondansetron, bicuculline, or CGP55845). Expression of 5-HT3 receptors, and the affinity and binding mode of bilirubin to 5-HT3A receptor were determined. Effects of bilirubin on γ-aminobutyric acid (GABA) pathway and the interactions with 5-HT3A receptor were tested. RESULTS: Bilirubin was elevated significantly in both serum and CSF in BDL rats, accompanied with the up-regulation of pain thresholds. Both of 5-HT3A receptor and GABA A receptor antagonists could reverse the increased pain threshold in BDL rats. Further, 5-HT3A and GABA A receptor expressions were increased in BDL rats or intervention with bilirubin. Molecular docking suggested that bilirubin entered the hydrophobic pocket pre-formed in 5-HT3A receptor with potential hydrogen bonding. Bilirubin also increased GABA concentrations in CSF and GABAergic spontaneous inhibitory postsynaptic current in spinal cord, and directly induced inward currents in HEK293 cells which were overexpressed 5-HT3A receptor by lentivirus. CONCLUSION: In conclusion, bilirubin induced pain desensitization in cholestasis by activating 5-HT3A receptor in spinal cord. The activation of 5-HT3A receptor might regulate pain threshold by acting on the GABA pathway.

Folic acid alleviates jaundice of phenylhydrazine (PHA)-induced neonatal rats by reducing Lys-homocysteinylation of albumin.

Neonatal jaundice is a common symptom that occurs in neonates during the first month of their life and is generally divided into physiological and pathological subtypes. In serious cases, pathological neonatal jaundice frequently shows complications including seizures, cerebral palsy, and kernicterus. However, due to the unclear pathogenesis of pathological neonatal jaundice, effective drugs for this disease remain unsatisfied. In the present study, we first estimated the protective effects of folic acid (FA) on phenylhydrazine (PHA) or homocysteine (Hcy)-injected neonatal rats (2-3 days aged). Intriguingly, we found that FA significantly decreased the elevated total bilirubin (TBIL) and direct bilirubin (DBIL) concentration, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) activity in PHA- or Hcy-injected rats, indicating that FA improves liver functions. Meanwhile, our results also showed that the plasma Hcy level and N-homocysteinylation (N-Hcy) modification of albumin were significantly elevated in the jaundice rats, which were obviously reversed after FA administration. Furthermore, we identified a novel N-Hcy modification site K545 of human serum albumin (HSA) using LC-MS/MS, and the mutagenesis assay in HEK293 further validated these observations. Besides, we demonstrated that the N-Hcy modification of albumin functionally inhibits the bilirubin-binding ability of albumin without altering its protein level both in vitro and in vivo. Altogether, we highlight a mechanism that FA reduces the plasma Hcy level and thereby enhance the bilirubin-binding ability of albumin, which may provide a novel therapeutic strategy for the treatment of pathological neonatal jaundice.

Effect of remote ischemic preconditioning on hepatic ischemia-reperfusion injury in patients undergoing liver resection: a randomized controlled trial.

BACKGROUND: Studies in animal models have shown that remote ischemic preconditioning (RIPC) could protect the liver from hepatic ischemia-reperfusion injury (HIRI). The aim of this study was to examine whether RIPC could reduce HIRI in patients undergoing liver resection. METHODS: A total of 120 patients were randomly assigned to three groups: a control group receiving no conditioning, an ischemic preconditioning (IPC) group, and an RIPC group. In the IPC group, the hepatoduodenal ligament was blocked for 10 min followed by 10 min of reperfusion prior to hepatic resection. Patients in the RIPC group received three cycles of 5-min ischemia followed by 5-min reperfusion to the right arm. Alanine transaminase (ALT), aspartate transaminase (AST), and tumor necrosis factor-like weak inducer of apoptosis (TWEAK) were examined before and after surgery. RESULTS: A total of 105 patients completed the trial: 39 in the control group, 32 in the IPC group, and 34 in the RIPC group. In comparison to the control, serum ALT and AST levels significantly decreased in the IPC (ALT: 507.0±401.3 vs. 1040.7±649.5 IU/L, P<0.001; AST: 495.8±369.4 vs. 935.9±640.7 IU/L, P=0.001) and RIPC (ALT: 680.8±291.5 vs. 1040.7±649.5 IU/L, P=0.002; AST: 661.7±290.6 vs. 935.9±640.7 IU/L, P=0.014) groups on the first postoperative day. In comparison to the control, TWEAK significantly decreased in the IPC group (IPC 57.99±17.8 vs. control 76.13±12.4 ng/L, P=0.025) after surgery. TWEAK did not differ between the RIPC and IPC groups (RIPC 64.84±14.2 vs. IPC 57.99±17.8 ng/L, P=0.385). CONCLUSIONS: RIPC could reduce hepatic ischemia-reperfusion injury after liver resection.

Involvement of the p38 MAPK-pHsp27 pathway in vascular hyporeactivity induced by obstructive jaundice in rats.

Patients with obstructive jaundice are prone to develop cardiovascular complications during surgery. However, the underlying mechanisms remain largely unknown. The present study was aimed to investigate the role of p38 MAPK-pHsp27 pathway in vascular hyporesponsiveness induced by obstructive jaundice. Firstly, an experimental rat obstructive jaundice model was established by bile duct ligation (BDL). We found that the thoracic aorta rings isolated from BDL rats showed decreased response to norepinephrine and acetylcholine, while continuous intraperitoneal injection with SB203580, a selective P38 MAPK inhibitor, could significantly prevented BDL-induced hyporeactivity. Also, the immunohistochemistry and Western blot assays revealed that the up-regulation of pHsp27 and F-actin in thoracic aorta rings from BDL rats and bilirubin-treated vascular smooth muscle cells (VSMCs) were also inhibited by SB203580. Moreover, we identified that bilirubin could induced decreased cell proliferation of VSMCs by using CCK8 assay and which was also prevented by SB203580. All these data demonstrated that p38 MAPK-pHsp27 mediates vascular hyporesponsiveness in rats with obstructive jaundice by modulating the expression level of pHsp27 and F-actin, and that inhibition of p38 MAPK signaling could remodel the vascular activity.

Transgenic increase in the ß-endorphin concentration in cerebrospinal fluid alleviates morphine-primed relapse behavior through the µ opioid receptor in rats.

BACKGROUND: Opioid-primed relapse is a global burden. Although current strategies have improved, optimal therapy is urgently needed. METHODS: A recombinant adenovirus (Ad-NEP) expressing ß-endorphin (ß-EP) was designed and injected intracerebroventricularly (icv) into the right lateral ventricle in rats. Spatial and temporal ß-EP expression in the lateral ventricle wall, subventricular zone and adjacent choroid plexus and the ß-EP concentration in the cerebrospinal fluid (CSF) were observed during a 21-day period. A morphine priming-induced conditioned place preference (CPP) rat model was established. The ß-EP-ir neuron counts, CSF ß-EP concentration, and CPP score, which were used to evaluate morphine-primed reinstatement following extinction, were recorded 7 days after the icv injection. Additionally, the rats were pretreated with the irreversible µ opioid receptor antagonist ß-funaltrexamine (ß-FNA) and the selective κ opioid receptor antagonist nor-binaltorphimine (nor-BNI) to identify the receptor-dependent mechanism. RESULTS: Both peak ß-EP expression in target neurons and the peak CSF ß-EP concentration occurred 7 to 8 days after Ad-NEP icv injection. The sustainable increase in the CSF ß-EP concentration was correlated with a decrease in the CPP score 7 days after the Ad-NEP icv injection. Furthermore, reinstatement was almost reversed by ß-FNA pretreatment 24 hours before the behavioral test, but nor-BNI had little effect. CONCLUSION: The increasing cerebrospinal fluid ß-endorphin concentrations showed that the therapeutic effect on opioid relapse occurred predominantly through a µ opioid receptor-dependent mechanism. The Ad-NEP adenovirus can be considered an alternative therapy for opioid relapse.

Spironolactone rescues renal dysfunction in obstructive jaundice rats by upregulating ACE2 expression.

Postoperative acute renal failure in patients with obstructive jaundice is still a serious clinically complication, yet the mechanisms remain unclear. Renin-angiotensin-aldosterone system (RAAS) plays a central role in renal disease progression. Several lines of evidence shows that angiotensin-converting-enzyme-2 (ACE2), a main effector of RAAS acts as a local regulator for renal protection. This study aims to investigate the role of ACE2 and the effect of spironolactone treatment in obstructive jaundice(OJ) rats with renal injury. The rats with obstructive jaundice were established by bile duct ligation. Total bilirubin (TBil), serum creatinine (Scr) and the expression of ACE2 in kidney tissue of obstructive jaundice rats were detected. Comparatively, the expression of ACE2, renin, angiotensin II (AngII), angiotensin-(1-7)[Ang-(1-7)], aldosterone and intercellular adhesion molecule 1 (ICAM-1) in kidney tissues after spironolactone administration were measured by ELISA. Renal necrosis, inflammation and fibrosis induced by OJ were also measured by HE staining and Masson staining. The correlation between the expression of ACE2 and TBil, also the Scr level were investigated. With the time of common bile duct ligation prolonged, the TBil and Scr concentration increased while the expression of ACE2 in OJ rats' kidney tissues decreased. However, after spironolactone intervention, the expressions of ACE2, renin, AngII, Ang-(1-7), aldosterone and ICAM-1 in kidney tissue were changed, moreover, necrotic, inflammatory and fibrotic condition was also decreased. The relationship between the mRNA expression of ACE2 and TBil/Scr was observed to be moderately negatively correlated (r = -0.516, R2 = 0.292, P < 0.01), (r = -0.576, R2 = 0.332, P < 0.01), respectively. RAAS exerted an important effect in the renal damage caused by OJ. Spironolactone intervention not only improved the degree of renal fibrosis induced by OJ, but also upregulated the ACE2 expression in the kidney of OJ rats and rescued the renal function.

Lentiviral­mediated inducible silencing of TLR4 attenuates neuropathic pain in a rat model of chronic constriction injury.

An increasing body of evidence has indicated that spinal microglial Toll­like receptor 4 (TLR4) may serve a significant role in the development and maintenance of neuropathic pain (NP). In the present study, experiments were conducted to evaluate the contribution of a tetracycline inducible lentiviral­mediated delivery system for the expression of TLR4 small interfering (si)RNA to NP in rats with chronic constriction injury (CCI). Behavioral tests, including paw withdrawal latency and paw withdrawal threshold, and biochemical analysis of the spinal cord, including western blotting, reverse transcription­quantitative polymerase chain reaction and ELISA, were conducted following CCI to the sciatic nerve. Intrathecal administration of LvOn­si­TLR4 with doxycycline (Dox) attenuated allodynia and hyperalgesia. Biochemical analysis revealed that the mRNA and proteins levels of TLR4 were unregulated following CCI to the sciatic nerve, which was then blocked by intrathecal administration of LvOn­siTLR4 with Dox. The LvOn­siTLR4 was also demonstrated to have no effect on TLR4 or the pain response without Dox, which indicated that the expression of siRNA was Dox­inducible in the lentivirus delivery system. In conclusion, TLR4 may serve a significant role in neuropathy and the results of the present study provide an inducible lentivirus­mediated siRNA against TLR4 that may serve as a potential novel strategy to be applied in gene therapy for NP in the future.