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Postoperative pulmonary complications including acute lung injury (ALI) and acute respiratory distress syndrome have contributed to mortality and morbidity of orthotopic liver transplantation (OLT) with unclear mechanisms. Mast cells (MCs) and polymorphonuclear neutrophils (PMNs) are the main inflammatory cells and participants in the process of ALI. The present study was designed to investigate the role of MCs and PMNs and their potential relation to ALI following OLT. Rat orthotopic autologous liver transplantation (OALT) model was designed to determine lung injury at different time points after liver reperfusion. We also evaluated the function of MCs and the effect of tumor necrosis factor-α (TNF-α) and tryptase on ALI and PMN apoptosis in rats subjected to OALT. Histological scores and inflammatory factor levels as well as PMN apoptosis were measured. Rats suffered from ALI after OALT, which was demonstrated by a collapse of the pulmonary architecture, pulmonary edema, and infiltration of inflammatory cells in alveolar and interstitial spaces, as well as increased levels of proinflammatory cytokines. ALI maximized at 8 h after OALT. However, PMN apoptosis lagged behind the pulmonary injury and maximized at 16 h after OALT, when the acute inflammation resolution initiated. MC stabilization, and tryptase and TNF-α inhibitors could significantly decrease the lung pathophysiologic scores accompanied by an increase in PMN apoptosis. ALI after OALT was associated with MC activation and PMN apoptosis. ALI progression might be affected by delayed PMN apoptosis, which was related to MC activation. Induction of PMN apoptosis might alleviate ALI after OALT.

Macrophages play important roles in diabetes and sepsis-related intestinal injury. Accumulating evidence suggests that microRNAs (miRNAs) act as the fundamental link between macrophage polarization and tissue injury. However, the underlying mechanisms of miRNAs in regulating macrophage polarization-related intestinal injury under diabetes and sepsis conditions remain unclear.The cecal ligation and puncture (CLP)-induced sepsis models were established in male wild-type (WT) and diabetic mice. Clodronate liposome was used to deplete macrophage. HE staining, inflammatory cytokines [tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and IL-6], and intestinal mucosal barrier function markers [occludin, ZO-1, lipopolysaccharide (LPS), and intestinal fatty acid binding protein (iFABP)] were used to assess elevated intestinal damage. miRNA array, RNA-seq, and bioinformatic analysis were performed to detect the miRNA and messenger RNA (mRNA) expression and the potential regulation mechanism.Compared with WT CLP mice, the diabetic CLP mice showed severe intestinal damage characterized by significant increases in Chui's scores, expression of inflammatory cytokines (TNF-α, IL-1β, and IL-6), serum LPS and iFABP concentration, and significant reductions in tight junction protein occludin and ZO-1 levels. Macrophage depletion reversed the intestinal damage caused by CLP. The bioinformatic analysis revealed that miR-3061/Snail1 might be a potential regulation axis of macrophage polarization. Furthermore, high glucose and LPS stimulation increased M1 macrophage and reduced the levels of miR-3061, which was negatively associated with Snail1 in RAW264.7 cells. Mechanistic studies demonstrated that miR-3061 regulated macrophage polarization by targeting the Snail1 mRNA 3'-untranslated region. Moreover, miR-3061 overexpression suppressed Snail1 expression and inhibited M1 macrophage and inflammatory cytokines.This study elucidated that diabetes exacerbated sepsis-induced intestinal injury by promoting M1 macrophage polarization and further demonstrated that the miR-3061/Sani1 axis may be the potential target of macrophage polarization.

BACKGROUND Effects of liver dysfunction on target-controlled infusion (TCI) with Marsh parameters of propofol remain poorly documented. The purpose of this study was to evaluate the performance of propofol TCI in a cohort of Chinese patients with severe hepatic insufficiency. MATERIAL AND METHODS We assigned 32 patients who underwent liver transplantation to 3 groups according to Child-Turcotte-Pugh (CTP) score. Anesthesia, preceding liver transplantation, was induced and maintained with TCI of 3 µg/mL propofol. Plasma propofol concentration was assessed. Propofol TCI system performance was analyzed in terms of error size, bias, and divergence. Data on plasma propofol concentrations were analyzed, and population pharmacokinetic parameters of propofol were fitted by NONMEM software. RESULTS In the CTP C group, measured concentrations of propofol were much higher than those of predictive concentrations, with significantly higher overshoots compared to CTP A patients. Overall, TCI system performance was significantly lower in CTP C patients. Linear regression equations of Cm vs. Cp and a regression model of pharmacokinetics were obtained. CONCLUSIONS Propofol TCI device performance with Marsh parameters was clinically acceptable in CTP A patients but may not be suitable for patients with severe hepatic impairment.

Patients with orthotopic liver transplantation (OLT) frequently develop acute gut injury (AGI), and dexmedetomidine (Dex) has been reported to exert a protective effect against AGI. We investigated whether Dex protects against AGI through antioxidative stress effects by the Nrf2/HO-1 antioxidative signaling pathway. Rats were randomly allocated into a sham group and six orthotopic autologous liver transplantation (OALT) groups receiving different doses of Dex together with/without α2-adrenergic receptor (AR) blockers. Intestinal tissues were collected to visualize the barrier damage and to measure the indexes of oxidative stress. For in vitro studies, rat intestinal recess epithelial cells (IEC-6) underwent hypoxia/reoxygenation (H/R), and the protective role of Dex was evaluated after α2A-AR siRNA silencing. OALT resulted in increased oxidative stress, significant intestinal injury, and barrier dysfunction. Dex attenuated OALT-induced oxidative stress and intestinal injury, which was abolished by the pretreatment with the nonspecific α2A-AR siRNA blocker atipamezole and the specific α2A-AR siRNA blocker BRL-44408, but not by the specific 2B/C-AR siRNA blocker ARC239. Silencing of α2A-AR siRNA also attenuated the protective role of Dex on alleviating oxidative stress in IEC-6 cells subjected to H/R. Dex exerted its protective effects by activating Nrf2/HO-1 antioxidative signaling. Collectively, Dex attenuates OALT-induced AGI via α2A-AR-dependent suppression of oxidative stress, which might be a novel potential therapeutic target for OALT-induced AGI.

Background Nuclear factor-E2–related factor 2 (Nrf2)–mediated antioxidant response is the main protective system of graft-liver against ischemia–reperfusion injury after liver transplantation. Propofol is considered to confer protective effects on different organs; thus, we explored the possibility that whether propofol could attenuate graft-liver injury in a rat autologous orthotopic liver transplantation (AOLT) model and mechanisms were associated with activation of Nrf2 pathway. Methods Sprague–Dawley rats were randomly divided into four groups: sham-operated group, saline-treated AOLT group, low-dose propofol intervention group, and high-dose propofol intervention group. Liver injury was determined, and concentration of hydroxyl free radical (•OH), superoxide anion (O 2 •− ), and malondialdehyde in the liver tissue were detected. The expression of Keap1, Nrf2, HO-1, and NQO1 were explored by Western blotting, and also the change of Nrf2 and keap1 was assessed by immunofluorescence. Results Compared with sham group, pathologic damage of graft-livers was in a time-dependent manner, accompanied with the increased level of oxidative stress in the AOLT group, and nuclear Nrf2 expression and its downstream antioxidant enzyme, HO-1 and NQO1, were also increased in this group. However, in propofol pretreatment groups especially in the high-dose group, the pathologic score was significantly decreased, accompanied with a lower level of •OH, O 2 •− , and malondialdehyde than that of the AOLT group. The change of oxidative stress might be related to the Nrf2 pathway, evidenced as the elevation of protein expression level of NQO1, HO-1, and nuclear Nrf2. Conclusions Protective effects of propofol against liver transplantation–induced graft-liver injury may be related with Keap1-Nrf2 signal pathway activation.

The purpose of this study was to determine the effect of sulforaphane (SFN) on hepatic ischemia reperfusion injury (HIRI) and to explore the underlying mechanisms.The rat model of HIRI was established. Thirty-two rats were randomly divided into sham (A), SFN (B), HIRI (C), and SFN + HIRI (D) groups. Animals in the HIRI and Sham groups were treated with equal volumes of the vehicle of SPF. Liver functions were evaluated by serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Liver samples were collected for histological examination and determination of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), and glutathione peroxidase (GSH-Px) levels. Mitochondrial Na(+)-K(+)-ATPase and Ca(2+)-ATPase were measured by colorimetry. Expression levels of NQO1, Nrf2, and HO-1 in liver tissue were detected by western blot analysis. Additionally, oncosis and apoptosis were detected by Annexin V-FITC/PI immunofluorescent flow cytometry analysis.The HIRI group showed a significant increase in serum levels of liver enzymes (ALT, AST) associated with histopathological damage in the liver. Pre-treatment with SFN could reduce the levels of MDA and MPO in liver tissue and improve the activities of SOD, GSH, GSH-Px, and mitochondrial Na(+)-K(+)-ATPase and Ca(2+)-ATPase in liver tissue. Moreover, SFN could still increase the expression of NQO1, Nrf2, and HO-1 in liver tissue and decrease the oncosis and apoptosis of liver cells.Pre-treatment with SFN could attenuate HIRI via the activation of Nrf2/ARE signaling pathways, ameliorate oxidative stress, and maintain the normal activities of Na(+)-K(+)-ATPase and Ca(2+)-ATPase, thus reducing the occurrence of cell oncosis and apoptosis. Therefore, SFN can be considered a potential candidate as an anti-ischemic medication to minimize HIRI.

Background: Postliver transplantation acute kidney injury (AKI) severely affects patient survival, whereas the mechanism is unclear and effective therapy is lacking. The authors postulated that reperfusion induced enhancement of connexin32 (Cx32) gap junction plays a critical role in mediating postliver transplantation AKI and that pretreatment/precondition with the anesthetic propofol, known to inhibit gap junction, can confer effective protection. Methods: Male Sprague–Dawley rats underwent autologous orthotopic liver transplantation (AOLT) in the absence or presence of treatments with the selective Cx32 inhibitor, 2-aminoethoxydiphenyl borate or propofol (50 mg/kg) (n = 8 per group). Also, kidney tubular epithelial (NRK-52E) cells were subjected to hypoxia–reoxygenation and the function of Cx32 was manipulated by three distinct mechanisms: cell culture in different density; pretreatment with Cx32 inhibitors or enhancer; Cx32 gene knock-down (n = 4 to 5). Results: AOLT resulted in significant increases of renal Cx32 protein expression and gap junction, which were coincident with increases in oxidative stress and impairment in renal function and tissue injury as compared to sham group. Similarly, hypoxia–reoxygenation resulted in significant cellular injury manifested as reduced cell growth and increased lactate dehydrogenase release, which was significantly attenuated by Cx32 gene knock-down but exacerbated by Cx32 enhancement. Propofol inhibited Cx32 function and attenuated post-AOLT AKI. In NRK-52E cells, propofol reduced posthypoxic reactive oxygen species production and attenuated cellular injury, and the cellular protective effects of propofol were reinforced by Cx32 inhibition but cancelled by Cx32 enhancement. Conclusion: Cx32 plays a critical role in AOLT-induced AKI and that inhibition of Cx32 function may represent a new and major mechanism whereby propofol reduces oxidative stress and subsequently attenuates post-AOLT AKI.

Acute lung injury (ALI) is a severe complication of orthotopic liver transplantation (OLT) with unclear underline mechanism. Toll-like receptor 4 (TLR4) has been identified as a key receptor mediating inflammation. We hypothesized that TLR4-mediated pulmonary inflammation may contribute to development of ALI during OLT. Patients with or without ALI were observed for serum cytokines and expression of TLR4 on peripheral blood polymorphonuclear leukocytes (PMNs). Next, rats which underwent orthotopic autologous liver transplantation (OALT) were divided into sham and model groups. Pulmonary function and the level of TLR4 expression and cytokines were analyzed. Furthermore, the role of TLR4 in OALT-mediated ALI was assessed in rats treated with TLR4-siRNA before OALT. The PMNs TLR4 expression and the serum TNF-αand IL-βlevel were higher in patients with ALI than those with non-ALI. Interestingly, lung TLR4 expression was significantly increased after 8 hours of OALT with increased levels of TNF-αand IL-β, which lead to lung pathological damage and an increase of lung myeloperoxidase content. Moreover, knockdown of TLR4 reduced lung cytokines release and reversed the above pathologic changes after OALT and finally improved rats’ survival rate. In conclusion, TLR4 overexpression, potentially by stimulating proinflammatory cytokine overproduction, contributes to the development of ALI after OLT.

Aims. This study was aimed at investigating whether elevation of heme oxygenase-1 (HO-1) expression could lead to restoring intestinal tight junction (TJ) function in a rat liver transplantation model.Methods. Intestinal mucosa injury was induced by orthotopic autologous liver transplantation (OALT) on male Sprague-Dawley rats. Hemin (a potent HO-1 activator) and zinc-protoporphyrin (ZnPP, a HO-1 competitive inhibitor), were separately administered in selected groups before OALT. The serum and intestinal mucosa samples were collected at 8 hours after the operation for analysis.Results. Hemin pretreatment significantly reduced the inflammation and oxidative stress in the mucosal tissue after OALT by elevating HO-1 protein expression, while ZnPP pretreatment aggravated the OALT mucosa injury. Meanwhile, the restriction on the expression of tight junction proteins zonula occludens-1 and occludin was removed after hemin pretreatment. These molecular events led to significant improvement on intestinal barrier function, which was proved to be through increasing nuclear translocation of nuclear factor-E2-related factor 2 (Nrf2) and reducing nuclear translocation of nuclear factor kappa-B (NF-κB) in intestinal injured mucosa.Summary. Our study demonstrated that elevation of HO-1 expression reduced the OALT-induced intestinal mucosa injury and TJ dysfunction. The HO-1 protective function was likely mediated through its effects of anti-inflammation and antioxidative stress.

Toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κB) signaling plays a dominant role in the pathogenesis of liver ischemia-reperfusion (IR) injury. Dexmedetomidine (Dex) protects the liver against IR injury via α2-adrenoceptor activation, but the contribution of TLR4 signaling remains unknown. The authors aimed to examine whether pretreatment with Dex produces hepatic protection and investigate the influence of Dex on TLR4/NF-κB signaling. Dex was given via intraperitoneal injection 30 min prior to orthotopic autologous liver transplantation (OALT) in rats, and three α2-adrenoceptor antagonists including atipamezole (a nonselective α2 receptor blocker), ARC-239 (a specific α2B/C blocker) and BRL-44408 (a specific α2A blocker) were injected intraperitoneally 10 min before Dex administration. Histopathologic evaluation of the liver and the measurement of serum alanine aminotransferase activity, TLR4/NF-κB expression in the liver, and pro-inflammatory factors (serum tumor necrosis factor-α, interleukin-1β and hepatic myeloperoxidase) concentrations were performed 8 h after OALT. Dex ameliorated liver injury after OALT probably by suppressing the TLR4/NF-κB pathway and decreasing inflammatory mediator levels. The protective effects of Dex were reversed by atipamezole and BRL-44408, but not by ARC-239, suggesting that these effects were mediated in part by the α2A subtype. In conclusion, Dex attenuates liver injury partly via the α2A-adrenoceptor subtype, and the mechanism is due to the suppression of the TLR4/NF-κB pathway.

Background Post-liver transplantation acute lung injury (ALI) severely affects patients’ survival, whereas the mechanism is unclear and effective therapy is lacking. The authors postulated that reperfusion-induced increased oxidative stress plays a critical role in mediating post-liver transplantation ALI and that induction of heme oxgenase-1 (HO-1), an enzyme with anti-oxidative stress properties, can confer effective protection of lung against ALI. Methods Male Sprague–Dawley rats underwent autologous orthotopic liver transplantation (OALT) in the absence or presence of treatments with the selective HO-1 inducer (Hemin) or HO-1 inhibitor (ZnPP). Lung tissues were collected at 8 h after OALT, pathological scores and lung water content were evaluated; survival rate of rats was analyzed; protein expression of HO-1 was determined by western blotting, and nuclear translocation of Nuclear factor erythroid 2-related factor 2 (Nrf2) and nuclear factor(NF)-κB p65 were detected by Immunofluorescence staining. The inflammatory cytokines and oxidative indexes of lung tissue were determined. Results In lungs harvested at the early stage i.e. 8 h after OALT, Hemin treatment significantly increased superoxide dismutase activities, and reduced malondialdehyde, hydrogen peroxide, interleukin-6, myeloperoxidase, and tumor necrosis factor-α production,which were associated with increased HO-1 protein expression and lower pathological scores and increased survival rate of rats. The underline mechanisms might associate with activation of Nrf2 and inhibition of NF-κB p65 nuclear translocation. However, these changes were aggravated by ZnPP. Conclusions Hemin pretreatment, by enhancing HO-1 induction, increased lung antioxidant capacity and reduced inflammatory stress,protected the lung from OALT-induced ALI at early stage of reperfusion.

This paper aims to explore whether pretreatment with dexmedetomidine (Dex) has antioxidative and renal protective effects during orthotopic autologous liver transplantation (OALT) and its impact on nuclear factor erythroid 2-related factor 2 (Nrf2) activation. Sprague-Dawley rats were randomized into groups that include sham-operated (group S), model (group M), low dose Dex (group D1), high dose Dex (group D2), atipamezole (a nonspecificα2receptor blocker) + high dose Dex (group B1), ARC239 (a specificα2B/creceptor blocker) + high dose Dex (group B2), and BRL-44408 (a specificα2Areceptor blocker) + high dose Dex (group B3). Then histopathologic examination of the kidneys and measurement of renal function, the renal Nrf2 protein expression, and oxidants and antioxidants were performed 8 hours after OALT. We found that pretreatment with Dex activated Nrf2 in glomerular cells and upregulated antioxidants but reduced oxidants (allP<0.01, group D2 versus group M). Atipamezole and BRL-44408, but not ARC239, reversed these protective effects. In conclusion, pretreatment with Dex activates Nrf2 throughα2Areceptor, increases the antioxidant levels, and attenuates renal injury during OALT.

Patients who undergo orthotopic liver transplantation often sustain acute kidney injury(AKI). The toll-like receptor 4(TLR4)/Nuclear factor-кB(NF-кB) pathway plays a role in AKI. Dexmedetomidine(Dex) has been shown to attenuate AKI. The current study aimed to determine whether liver transplantation-induced AKI is associated with inflammatory response and to assess the effects of dexmedetomidine pretreatment on kidneys in rats following orthotopic autologous liver transplantation(OALT). Seventy-seven adult male rats were randomized into 11 groups. Kidney tissue histopathology and levels of blood urea nitrogen(BUN) and serum creatinine(SCr) were evaluated. Levels of TLR4, NF-κB, tumor necrosis factor-α and interleukin-1β levels were measured in kidney tissues. OALT resulted in significant kidney functional impairment and tissue injury. Pre-treatment with dexmedetomidine decreased BUN and SCr levels and reduced kidney pathological injury, TLR4 expression, translocation of NF-κB and cytokine production. The effects of dexmedetomidine were reversed by pre-treatment with atipamezole and BRL44408, but not ARC239. These results were confirmed by using α2A-adrenergic receptor siRNA which reversed the protective effect of dexmedetomidine on attenuating NRK-52E cells injury induced by hypoxia reoxygenation. In conclusion, Dexmedetomidine-pretreatment attenuates OALT-induced AKI in rats which may be contributable to its inhibition of TLR4/MyD88/NF-κB pathway activation. The renoprotective effects are related to α2A-adrenergic receptor subtypes.

Background To investigate whether pretreatment with dexmedetomidine (Dex) has a protective effect against acute lung injury (ALI) in an orthotopic autologous liver transplantation (OALT) rat model and to explore the mechanisms responsible for the protective effect of Dex against lung injury. Methods Forty-eight rats underwent OALT and were randomly divided into six groups (n = 8 in each group) that received 10 µg/kg Dex, 50 µg/kg Dex, 50 µg/kg Dex + nonspecific α2-adrenergic receptor (AR) antagonist atipamezole, 50 µg/kg Dex + specific α2B/C-AR antagonist ARC-239, 50 µg/kg Dex + specific α2A-AR antagonist BRL-44408, or the same amount of normal saline. The sham rats (n = 8) underwent anesthesia induction, laparotomy, and separation of the portal vein without liver ischemia and reperfusion. Lung tissue sections were stained with hematoxylin and eosin (HE) to visualize the damage. The expression of Toll-like receptor 4 (TLR4) and the phospho-nuclear factor (NF)-κB p65 subunit as well as inflammatory cytokines was measured. Results Rats exhibited increased histological lung injury scores and pulmonary edema following OALT. Pretreatment with 50 μg/kg Dex attenuated OALT-induced lung injury in rats, probably by inhibiting the activation of the TLR4–NF-κB signaling pathway. The protective effect of Dex could be blocked by atipamezole or BRL-44408, but not by ARC-239, suggesting these effects of Dex were mediated, at least in part, by the α2A-AR. Conclusions Dex exerts protective effects against ALI following OALT, and this protection is associated with the suppression of TLR4–NF-κB signaling. Thus, pretreatment with Dex may be a useful method for reducing lung damage caused by liver transplantation.

Nuclear factor erythroid 2‑related factor 2 (Nrf2) is a critical regulator of the cellular‑defense response in protection against oxidative injury. Several studies have demonstrated that propofol ameliorates ischemia/reperfusion injury in a number of organs. However, whether propofol exerts renal protection against liver transplantation via Nrf2 activation remains to be elucidated. The aim of the present study was to investigate the effects of orthotopic liver autotransplantation (OLAT) on renal Nrf2 expression and to determine whether propofol protects against kidney injury induced by OLAT via Nrf2 activation. A total of 24 male Sprague Dawley rats were randomly divided into four groups: sham surgery + normal saline (sham group); OLAT + normal saline (OLAT group); OLAT + propofol 50 mg/kg (L‑Prop group) and OLAT + propofol 100 mg/kg (H‑Prop group). Normal saline and propofol were administered for 3 consecutive days through an intraperitoneal injection prior to surgery. Kidney pathology, blood urea nitrogen (BUN), creatinine (Cr), superoxide anion (O2•‑), hydroxyl radical (·OH), maleic dialdehyde (MDA) and expression levels of Nrf2, Kelch‑like ECH‑associated protein 1 (Keap1), heme oxygenase‑1 (HO‑1) and NADP quinine oxidoreductase 1 (NQO1) were assessed 8 h after OLAT. It was demonstrated that OLAT induced remote kidney damage. Pretreatment with propofol significantly ameliorated renal pathology and abrogated the increase of the Cr and BUN concentrations, O2•‑ and ·OH activities, and MDA levels induced by OLAT. In the H‑Prop group, Keap1 expression in the cytoplasm was decreased and Nrf2 expression in the nucleus was upregulated, accompanied by an increase of HO‑1 and NQO1 expression. The present results suggest that propofol pretreatment exerted renal protection against OLAT, with the upregulation of nuclear Nrf2 expression as a potential mechanism.

OBJECTIVE: This study aimed to investigate whether propofol pretreatment can protect against liver transplantation-induced acute lung injury (ALI) and to explore whether Nrf2 pathway is involved in the protections provided by propofol pretreatment. METHOD: Adult male Sprague-Dawley rats were divided into five groups based on the random number table. Lung pathology was observed by optical microscopy. Lung water content was assessed by wet/dry ratio, and PaO2 was detected by blood gas analysis. The contents of H2O2, MDA, and SOD activity were determined by ELISA method, and the expression of HO-1, NQO1, Keap1, and nuclear Nrf2 was assayed by western blotting. RESULTS: Compared with saline-treated model group, both propofol and N-acetylcysteine pretreatment can reduce the acute lung injury caused by orthotopic autologous liver transplantation (OALT), decrease the lung injury scores, lung water content, and H2O2 and MDA levels, and improve the arterial PaO2 and SOD activity. Furthermore, propofol (but not N-acetylcysteine) pretreatment especially in high dose inhibited the expression of Keap1 and induced translocation of Nrf2 into the nucleus to further upregulate the expression of HO-1 and NQO1 downstream. CONCLUSION: Pretreatment with propofol is associated with attenuation of OALT-induced ALI, and the Nrf2 pathway is involved in the antioxidative processes., published_or_final_version

Acute lung injury (ALI) induced by liver transplantation is detrimental to patient survival, and therapeutic strategies remain limited. Thus, the protective effects of propofol, a commonly used anesthetic with antioxidative and anti‑inflammatory properties, were investigated in the present study on ALI induced by orthotopic autologous liver transplantation (OALT). The protective mechanism of propofol was determined to be associated with the inhibition of NADPH oxidase, by comparing its effects with the positive controls apocynin (AP; an NADPH oxidase inhibitor) and N‑acegysteine (NAC; a scavenger of reactive oxygen species). The results demonstrated that two proteins (p47phox and gp91phox) of the NADPH oxidase system presented increased expression in rats with ALI induced by OALT, thus leading to increased activation of the oxidative stress and inflammatory reactions. Preconditioning with NAC or AP eliminated this increase, suggesting that antioxidative treatment, particularly with inhibitors of NADPH oxidase, is a promising protective strategy against ALI induced by OALT. Propofol preconditioning at a high (100 mg/kg) or low (50 mg/kg) dose promoted similar protective effects, with the high‑dose propofol producing a more marked effect than the low dose. The results suggested that propofol may protect against ALI induced by OALT, the mechanism of which may involve a reduced oxidative stress and inflammatory reaction mediated by NADPH oxidase inhibition.

BACKGROUND: Acute lung injury (ALI) is one of the most severe complications after orthotopic liver transplantation. Amplified inflammatory response after transplantation contributes to the process of ALI, but the mechanism underlying inflammation activation is not completely understood. We have demonstrated that mast cell stabilization attenuated inflammation and ALI in a rodent intestine ischemia/reperfusion model. We hypothesized that upregulation of inflammation triggered by mast cell activation may be involve in ALI after liver transplantation. METHODS: Adult male Sprague-Dawley rats received orthotopic autologous liver transplantation (OALT) and were executed 4, 8, 16, and 24 h after OALT. The rats were pretreated with the mast cell stabilizers cromolyn sodium or ketotifen 15 min before OALT and executed 8 h after OALT. Lung tissues and arterial blood were collected to evaluate lung injury. β-hexosaminidase and mast cell tryptase levels were assessed to determine the activation of mast cells. Tumor necrosis factor α (TNF-α), interleukin (IL)-1β and IL-6 in serum and lung tissue were analyzed by enzyme-linked immunosorbent assay. Nuclear factor-kappa B (NF-κB) p65 translocation was assessed by Western blot. RESULTS: The rats that underwent OALT exhibited severe pulmonary damage with a high wet-to-dry ratio, low partial pressure of oxygen, and low precursor surfactant protein C levels, which corresponded to the significant elevation of pro-inflammatory cytokines, β-hexosaminidase, and tryptase levels in serum and lung tissues. The severity of ALI progressed and maximized 8 h after OALT. Mast cell stabilization significantly inhibited the activation of mast cells, downregulated pro-inflammatory cytokine levels and translocation of NF-κB, and attenuated OALT-induced ALI. CONCLUSIONS: Mast cell activation amplified inflammation and played an important role in the process of post-OALT related ALI.

Background Acute lung injury (ALI) is a serious complication that commonly occurs during orthotopic liver transplantation (OLT). Toll-like receptor 2/4 (TLR2/4) are the main membrane receptors that respond to inflammatory stimuli and mediate NF-kappa B (NF-κB) signal pathway. We previously showed that TLR2/4 expression on monocytes and serum cytokine levels were increased in patients with ALI induced by OLT. Myeloid differentiation protein-2 (MD-2) expresses the functional domains that combines TLRs and play a key regulatory role in TLRs activation. Therefore, we hypothesized that blocking MD-2 would inhibit the TLR2/4-mediated inflammatory response and lessen ALI induced by liver transplantation. Method Thirty-two Sprague Dawley (SD) rats were randomly divided into four groups. One group received a sham operation (Group S), and the other three groups underwent orthotopic autologous liver transplantation (OALT) 48 h after intratracheal administration of saline (Model group; Group M), non-targeting siRNA (negative siRNA control group; Group NC) or siRNA against MD-2 (intervention group; Group RNAi). Lung pathology, lung water content, PaO2, and expression levels of MD-2, TLR2/4, NF-κB, TNF-α, IL-1β and IL-6 were assessed 8 h after OALT. Results In Groups M and NC, OALT produced marked lung pathology with decreased PaO2 levels and increased MD-2, TLR2/4 gene and protein expression levels. Furthermore, the nuclear translocation of the NF-κB P65 subunit, was increased, as were lung concentrations of TNF-α, IL-1β and IL-6. The pathology of ALI and the severity of the above biochemical changes induced by OALT were significantly reduced in the group treated with MD-2 siRNA. Conclusion MD-2 gene knock-down attenuated the increase in TLR2/4 activation and reduced ALI after OALT.

The aim of this study was to investigate the effects of small volume resuscitation with 7.5% hypertonic sodium chloride (HSS), hydroxyethyl starch 130/0.4 solution (HES), and hypertonic sodium chloride hydroxyethyl starch 40 injection (HSH) on endotoxin shock rat lung.Thirty Sprague-Dawley (SD) rats were divided randomly into 5 groups ，Group C (negative control group), Group E (lipopolysaccharide, LPS +4 ml/kg saline), Group HSS (LPS +4 ml/kg HSS), Group HES (LPS +4 ml/kg HES) and Group HSH (LPS +4 ml/kg HSH). Endotoxin shock model of rat was produced by injection with LPS. Then small volume resuscitation with different fluids was implemented in each group, respectively.Compared to Group C(negative control group）, lung injury in the other four groups was increased. Compared to Group E(LPS +4 ml/kg normal saline), lung injury of Group HSS(LPS +4 ml/kg HSS), HES(LPS +4 ml/kg HES), and HSH (LPS +4 ml/kg HSH)was lessened. Compared to Group C, oxygenation index in Groups E, HSS, HES, and HSH were decreased (P 0.01). Compared to Group E, oxygenation indexes in Groups HSS, HES, and HSH were significantly increased (P 0.01). Data of tumor necrosis factor (TNF)-α of lung tissue had similar results. However, protein concentration of bronchoalveolar lavage fluid and hydrogen sulfide (H(2)S) concentration indicated contrary results.Small volume resuscitation with 7.5% hypertonic sodium chloride, hydroxyethyl starch 130/0.4 solution, and hypertonic sodium chloride hydroxyethyl starch 40 injection could lessen lung injury caused by lipopolysaccharide. And this effect had relation to change of TNF-α and H(2)S.

Background. To explore the relationship between Toll-like rpheral blood mononuclear cells (PBMC) and systemic inflammatory response syndrome (SIRS) in postoperative patients of liver transplantation (LT).Methods. Blood samples of 27 patients receiving LT were collected at T1 (after induction of anaesthesia), T2 (25 minutes after the beginning of anhepatic phase), T3 (3 hours after graft reperfusion), and T4 (24 hours after graft reperfusion). The expression of TLR2/4 on PBMC and serum concentration of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-8 were measured. The patients were divided into SIRS group (n=12) and non-SIRS group (n=15) for analysis.Results. Blood loss and transfusion were higher in the SIRS group than in the non-SIRS group. Both the preanhepatic and anhepatic phase were significantly longer in the SIRS group. The TLR2/4 expression on PBMC as well as serum TNF-α, IL-1β, and IL-8 were significantly higher at T3 and T4 than that at T1 and T2 in the SIRS patients. The expression of TLR4 on PBMC is positively correlated to serum TNF-α, IL-8. Expression of TLR2/4 on PBMC and serum concentrations of TNF-α, IL-1β, did not differ among the 4-time points in non-SIRS patients.Conclusions. Upregulation of TLR2/4 expression on PBMC may contribute to the development of postoperative SIRS during perioperative period of LT.

Background Postoperative acute lung injury (ALI) is a severe complication after liver transplantation, which influences patient survival rate obviously. However, its mechanisms are unclear and effective therapies are still lacking. The current study focused on effects of propofol on liver transplantation-induced ALI and whether its underlying mechanism was relative with connexin43 (Cx43) alternation. The authors postulated that endotoxin induced enhancement of Cx43 gap junction (GJ) plays a critical role in mediating post liver transplantation ALI and that pretreatment with the anesthetic propofol, known to inhibit gap junction, can confer effective protection. Methods Male Sprague–Dawley rats underwent autologous orthotopic liver transplantation (AOLT) in the absence or presence of treatments with the selective Cx43 inhibitor, enanthol (0.1 mg/kg) and propofol (50 mg/kg), a commonly used anesthetic in clinical anesthesia. In vitro study, BEAS-2B cells, a kind of lung epithelial cell line expressing Cx43, exposed to lipopolysaccharide (LPS), which mainly contributed to ALI. Function of Cx43 GJ was regulated by Cx43 specific inhibitors, gap26 (300 μM) or enhancer, retinoic acid (10 μM) and two specific siRNAs. Results Compared with the sham group, AOLT results in ALI obviously with plasma endotoxin increase. Cx43 inhibition decreased ALI through inflammatory reaction reduction. In vitro studies, LPS-induced BEAS-2B cells damage was attenuated by Cx43 function inhibition, but amplified by enhancement. Another important finding was propofol reduced Cx43 function and protected against LPS-mediated BEAS-2B cells damage or AOLT-induced ALI, mechanisms of which were also associated with inflammatory reaction decrease. Conclusion Cx43 plays a vital role in liver transplantation-induced ALI. Propofol decreased Cx43 function and protected against ALI in vivo and in vitro. This finding provide a new basis for targeted intervention of organ protection in liver transplantation, even in other kinds of operations.