Isoform- and Cell Type-Specific Roles of Glycogen Synthase Kinase 3 N-Terminal Serine Phosphorylation in Liver Ischemia Reperfusion Injury.

Glycogen synthase kinase 3 (Gsk3) α and ß are both constitutively active and inhibited upon stimulation by N-terminal serine phosphorylation. Although roles of active Gsk3 in liver ischemia reperfusion injury (IRI) have been well appreciated, whether Gsk3 N-terminal serine phosphorylation has any functional significance in the disease process remains unclear. In a murine liver partial warm ischemia model, we studied Gsk3 N-terminal serine mutant knock-in (KI) mice and showed that liver IRI was decreased in Gsk3αS21A but increased in Gsk3ßS9A mutant KI mice. Bone marrow chimeric experiments revealed that the Gsk3α, but not ß, mutation in liver parenchyma protected from IRI, and both mutations in bone marrow-derived cells exacerbated liver injuries. Mechanistically, mutant Gsk3α protected hepatocytes from inflammatory (TNF-α) cell death by the activation of HIV-1 TAT-interactive protein 60 (TIP60)-mediated autophagy pathway. The pharmacological inhibition of TIP60 or autophagy diminished the protection of the Gsk3α mutant hepatocytes from inflammatory cell death in vitro and the Gsk3α mutant KI mice from liver IRI in vivo. Thus, Gsk3 N-terminal serine phosphorylation inhibits liver innate immune activation but suppresses hepatocyte autophagy in response to inflammation. Gsk3 αS21, but not ßS9, mutation is sufficient to sustain Gsk4 activities in hepatocytes and protect livers from IRI via TIP60 activation.

Activation of YAP attenuates hepatic damage and fibrosis in liver ischemia-reperfusion injury.

BACKGROUND & AIMS: Hepatic ischemia-reperfusion injury (IRI) is a major complication of hemorrhagic shock, liver resection and transplantation. YAP, a key downstream effector of the Hippo pathway, is essential for determining cell fate and maintaining homeostasis in the liver. We aimed to elucidate its role in IRI. METHODS: The role of YAP/Hippo signaling was systematically studied in biopsy specimens from 60 patients after orthotopic liver transplantation (OLT), and in a mouse model of liver warm IRI. Human biopsy specimens were collected after 2-10 h of cold storage and 3 h post-reperfusion, before being screened by western blot. In the mouse model, the role of YAP was probed by activating or inhibiting YAP prior to ischemia-reperfusion. RESULTS: In human biopsies, high post-OLT YAP expression was correlated with well-preserved histology and improved hepatocellular function at postoperative day 1-7. In mice, the ischemia insult (90 min) triggered intrinsic hepatic YAP expression, which peaked at 1-6 h of reperfusion. Activation of YAP protected the liver against IR-stress, by promoting regenerative and anti-oxidative gene induction, while diminishing oxidative stress, necrosis/apoptosis and the innate inflammatory response. Inhibition of YAP aggravated hepatic IRI and suppressed repair/anti-oxidative genes. In mouse hepatocyte cultures, activating YAP prevented hypoxia-reoxygenation induced stress. Interestingly, YAP activation suppressed extracellular matrix synthesis and diminished hepatic stellate cell (HSC) activation, whereas YAP inhibition significantly delayed hepatic repair, potentiated HSC activation, and enhanced liver fibrosis at 7 days post-IRI. Notably, YAP activation failed to protect Nrf2-deficient livers against IR-mediated damage, leading to extensive fibrosis. CONCLUSION: Our novel findings document the crucial role of YAP in IR-mediated hepatocellular damage and liver fibrogenesis, providing evidence of a potential therapeutic target for the management of sterile liver inflammation in transplant recipients. LAY SUMMARY: In the clinical arm, graft YAP expression negatively correlated with liver function and tissue damage after human liver transplantation. YAP activation attenuated hepatocellular oxidative stress and diminished the innate immune response in mouse livers following ischemia-reperfusion injury. In the mouse model, YAP inhibited hepatic stellate cell activation, and abolished injury-mediated fibrogenesis up to 7 days after the ischemic insult.

Hypoxia-inducible factor-2α promotes hepatocyte apoptosis during cholestasis.

AIM: Hypoxia-inducible factor-2α (HIF-2α) has been reported to play an important role in a host of pathophysiological processes, including cellular survival. This study explores the role of HIF-2α in cholestasis-mediated hepatocyte apoptosis. METHODS: Hypoxia-inducible factor-2α expression was measured by immunohistochemistry and confocal microscopy. Hepatic apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP-digoxigenin nick-end labeling. The cholestatic mouse model was treated with bile duct ligation. The c-myc, p53, and Bax protein levels were measured with Western blot analysis. RESULTS: In pediatric and murine cholestatic liver tissues, HIF-2α protein was widely expressed in the nucleus of parenchymal cells as well as in stromal cells. Hepatocyte HIF-2α expression was significantly elevated at the early stage of pediatric cholestasis and decreased at the late stage. In both in vivo and in vitro murine studies, HIF-2α deletion could alleviate cholestasis-mediated hepatocyte apoptosis and regulate the expression of c-myc, p53, and Bax proteins. CONCLUSION: These findings implied the contribution of HIF-2α to cholestasis-mediated hepatocyte apoptosis.

Expression of fibroblast growth factor 21 in patients with biliary atresia.

Fibroblast growth factor 21 is a critical circulating adipokine involving in metabolic disorders and various liver diseases. This study was performed to investigate whether FGF21 is also associated with the pathophysiology of biliary atresia. Serum FGF21 levels were measured in 57 BA patients and 20 age matched healthy controls. We also examined hepatic FGF21 mRNA expression and FGF21 protein levels in liver tissues obtained from 15 BA patients undergoing liver transplantation and 5 cases of pediatric donation after cardiac death donor without liver diseases by RT-PCR and Western blotting. Patients with BA showed significantly higher serum FGF21 levels than those without BA (554.7pg/mL [83-2300] vs. 124.5pg/mL [66-270], P<0.05). Patients with BA also had significantly higher FGF21 mRNA and protein levels in hepatic tissues than control subjects. Serum FGF21 expression increased corresponding to the severity of liver fibrosis. Furthermore, serum FGF21 levels dropped significantly in BA patients within 6months after liver transplantation and approached baseline in healthy controls (P>0.05). In vivo, FXR knockout could significantly abrogate cholestasis induced FGF21 expression. FGF21 levels in serum and liver tissue increased significantly in BA patients. In vivo, cholestasis could induce FGF21 expression in FXR dependent manner.

Increased mortality and aggravation of heart failure in liver X receptor-α knockout mice after myocardial infarction.

Liver X receptors, LXRα (NR1H3) and LXRß (NR1H2), are best known as nuclear oxysterol receptors and physiological master regulators of lipid and cholesterol metabolism. LXRα play a protective role in acute myocardial ischemia/reperfusion (MI/R) injury, but its role in myocardial infarction (MI) is unknown. The present study was undertaken to determine the effect of LXRα knockout on survival and development of chronic heart failure after MI. Wild-type (WT) and LXRα(-/-) mice were subjected to MI followed by serial echocardiographic and histological assessments. Greater myocyte apoptosis and inflammation within the infarcted zones were found in LXRα(-/-) group at 3 days after MI. At 4 weeks post-MI, LXRα(-/-) MI murine hearts demonstrated significantly increased infarct size, reduced ejection fraction (LXRα(-/-) 29.4 % versus WT 34.4 %), aggravated left ventricular (LV) chamber dilation, enhanced fibrosis and reduced angiogenesis. In addition, LXRα(-/-) mice had increased mortality compared with WT mice. LXRα deficiency increases mortality, aggravates pathological injury and LV remodeling induced by MI. Drugs specifically targeting LXRα may be promising in the treatment of MI.

Metformin decreases IL-22 secretion to suppress tumor growth in an orthotopic mouse model of hepatocellular carcinoma.

Epidemiological, preclinical and cellular studies in the last 5 years have shown that metformin exerts anti-tumoral properties, but its mode of action in cancer remains unclear. Here, we investigated the effects of metformin on a mouse hepatocellular carcinoma (HCC) model and tumor-associated T cell immune responses. Oral metformin administration led to a significant reduction of tumor growth, which was accompanied by decreased interleukin-22 (IL-22). Meanwhile, IL-22-induced STAT3 phosphorylation and upregulation of downstream genes Bcl-2 and cyclin D1 were inhibited by metformin. At the cellular level, metformin attenuated Th1- and Th17-derived IL-22 production. Furthermore, metformin inhibited de novo generation of Th1 and Th17 cells from naive CD4(+) cells. These observations were further supported by the fact that metformin treatment inhibited CD3/CD28-induced IFN-γ and IL-17A expression along with the transcription factors that drive their expression (T-bet [Th1] and ROR-γt [Th17], respectively). The effects of metformin on T cell differentiation were mediated by downregulated STAT3 and STAT4 phosphorylation via the AMP-activated kinase-mammalian target of rapamycin complex 1 pathway. Notably, metformin led to a reduction in glucose transporter Glut1 expression, resulting in less glucose uptake, which is critical to regulate CD4(+) T cell fate. Taken together, these findings provide evidence for the growth-inhibitory and immune-modulatory effects of metformin in HCC and thus, broaden our understanding about the action of metformin in liver cancer treatment.

Gut Microbiota-Derived Glutamine Attenuates Liver Ischemia/Reperfusion Injury via Macrophage Metabolic Reprogramming.

BACKGROUND & AIMS: Many studies have revealed crucial roles of the gut microbiota and its metabolites in liver disease progression. However, the mechanism underlying their effects on liver ischemia/reperfusion (I/R) injury remain largely unknown. Here, we investigate the function of gut microbiota and its metabolites in liver I/R injury. METHODS: C57BL/6 mice was pretreated with an antibiotic cocktail. Then, we used multi-omics detection methods including 16s rRNA sequencing, ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) to explore the changes of gut microbiota and metabolites in both feces and portal blood to reveal the mechanism of their protective effect in liver I/R injury. RESULTS: We found that antibiotic pretreatment (ABX) could significantly reduce the severity of I/R-induced hepatic injury, and this effect could be transferred to germ-free mice by fecal microbiota transplantation (FMT), suggesting a protective role of the gut microbiota depletion. During I/R, the rates of serum α-ketoglutarate (αKG) production and glutamate reduction, downstream products of gut microbiota-derived glutamine, were more significant in the ABX mice. Then, we showed that αKG could promote alternative (M2) macrophage activation through oxidative phosphorylation, and oligomycin A could inhibit M2 macrophage polarization and reversed this protective effect. CONCLUSIONS: These findings show that the gut microbiota and its metabolites play critical roles in hepatic I/R injury by modulating macrophage metabolic reprogramming. Potential therapies that target macrophage metabolism, including antibiotic therapies and novel immunometabolism modulators, can be exploited for the treatment of liver I/R injury.

HTLV-1 infection of donor-derived T cells might promote acute graft-versus-host disease following liver transplantation.

Acute graft versus host disease (aGVHD) is a rare, but severe complication of liver transplantation (LT). It is caused by the activation of donor immune cells in the graft against the host shortly after transplantation, but the contributing pathogenic factors remain unclear. Here we show that human T cell lymphotropic virus type I (HTLV-1) infection of donor T cells is highly associated with aGVHD following LT. The presence of HTLV-1 in peripheral blood and tissue samples from a discovery cohort of 7 aGVHD patients and 17 control patients is assessed with hybridization probes (TargetSeq), mass cytometry (CyTOF), and multiplex immunohistology (IMC). All 7 of our aGVHD patients display detectable HTLV-1 Tax signals by IMC. We identify donor-derived cells based on a Y chromosome-specific genetic marker, EIF1AY. Thus, we confirm the presence of CD4+Tax+EIF1AY+ T cells and Tax+CD68+EIF1AY+ antigen-presenting cells, indicating HTLV-1 infection of donor immune cells. In an independent cohort of 400 patients, we verify that HTLV-1 prevalence correlates with aGVHD incidence, while none of the control viruses shows significant associations. Our findings thus provide new insights into the aetio-pathology of liver-transplantation-associated aGVHD and raise the possibility of preventing aGVHD prior to transplantation.

A Clinical-Radiomic Model for Predicting Indocyanine Green Retention Rate at 15 Min in Patients With Hepatocellular Carcinoma.

Purpose: The indocyanine green retention rate at 15 min (ICG-R15) is of great importance in the accurate assessment of hepatic functional reserve for safe hepatic resection. To assist clinicians to evaluate hepatic functional reserve in medical institutions that lack expensive equipment, we aimed to explore a novel approach to predict ICG-R15 based on CT images and clinical data in patients with hepatocellular carcinoma (HCC). Methods: In this retrospective study, 350 eligible patients were enrolled and randomly assigned to the training cohort (245 patients) and test cohort (105 patients). Radiomics features and clinical factors were analyzed to pick out the key variables, and based on which, we developed the random forest regression, extreme gradient boosting regression (XGBR), and artificial neural network models for predicting ICG-R15, respectively. Pearson's correlation coefficient (R) was adopted to evaluate the performance of the models. Results: We extracted 660 CT image features in total from each patient. Fourteen variables significantly associated with ICG-R15 were picked out for model development. Compared to the other two models, the XGBR achieved the best performance in predicting ICG-R15, with a mean difference of 1.59% (median, 1.53%) and an R-value of 0.90. Delong test result showed no significant difference in the area under the receiver operating characteristic (AUROCs) for predicting post hepatectomy liver failure between actual and estimated ICG-R15. Conclusion: The proposed approach that incorporates the optimal radiomics features and clinical factors can allow for individualized prediction of ICG-R15 value of patients with HCC, regardless of the specific equipment and detection reagent (NO. ChiCTR2100053042; URL, http://www.chictr.org.cn).

Betaine/GABA transporter-1 (BGT-1) deficiency in mouse prevents acute liver failure in vivo and hepatocytes apoptosis in vitro.

Betaine/γ-aminobutyric acid (GABA) transporter 1 (BGT-1 or Slc6a12) is a transporter for the neurotransmitter GABA and osmolyte betaine. To date, most studies on BGT-1 have focused on its functions in the nervous system and renal osmotic homeostasis. Despite its dominant distribution in the liver, the function of BGT-1 in hepatic physiology or disease remains unknown. Here, we report that BGT-1 was significantly downregulated in patients with liver failure as well as in mice with experimental acute liver failure (ALF). Furthermore, mice deficient in BGT-1 showed significant resistance to ALF compared with wild type (WT) mice, manifesting as improved survival rate, reduced alanine transaminase/aspartate aminotransferase levels, better histopathological symptoms and fewer apoptotic cells in the liver. Similarly, in primary hepatocytes, BGT-1 deficiency or treatment with a BGT-1 inhibitor, NNC 05-2090, attenuated TNF-α mediated apoptosis. In addition, BGT-1 deficiency or dosing with NNC 05-2090 stimulated the expression of the anti-apoptotic gene, c-Met in the liver, suggesting the involvement of c-Met in the function on hepatocytes of BGT-1 apoptosis. Our findings suggest BGT-1 is a promising candidate drug target to prevent and treat hepatocyte apoptosis related diseases, such as ALF.

Farnesoid X Receptor Activation Protects Liver From Ischemia/Reperfusion Injury by Up-Regulating Small Heterodimer Partner in Kupffer Cells.

Farnesoid X receptor (FXR) is the nuclear receptor of bile acids and is involved in innate immune regulation. FXR agonists have been shown to protect multiple organs from inflammatory tissue injuries. Because liver expresses high levels of FXR, we explored the potential therapeutic benefits and underlying mechanisms of pharmacologic FXR activation in a murine model of partial liver warm ischemia. Pretreatment of mice with FXR agonist 3-(2,6-dichlorophenyl)-4-(3'-carboxy-2-chlorostilben-4-yl)oxymethyl-5-isopropylisoxazole (GW4064) attenuated liver ischemia/reperfusion injuries (IRIs) in wild-type but not FXR knockout mice. Posttreatment with GW4064 facilitated liver recovery from IRI. Mechanistically, Kupffer cells (KCs) expressed much higher levels of FXR than bone marrow-derived macrophages (BMMs). Pretreatment of KCs but not BMMs with GW4064 resulted in lower tumor necrosis factor α but higher interleukin-10 expressions following toll-like receptor stimulation. FXR-targeted gene small heterodimer partner (SHP) was critical for the regulation of KC response by GW4064. In vivo, the depletion of KCs but not cluster of differentiation (CD) 11b+ cells or knockdown of SHP diminished the immune regulatory effect of GW4064 in liver IRI. Thus, FXR activation protects liver from IRI by up-regulating SHP in KCs to inhibit the liver proinflammatory response.

Pituitary Adenylate Cyclase-activating Polypeptides Prevent Hepatocyte Damage by Promoting Yes-associated Protein in Liver Ischemia-Reperfusion Injury.

BACKGROUND: Hepatic ischemia-reperfusion injury (IRI) is a severe complication in liver transplantation, hepatectomy, and hemorrhagic shock. As neuropeptides transmit the regulatory signal between nervous and immune systems communication, our previous study documented that pituitary adenylate cyclase-activating polypeptides (PACAP) depressed hepatic Toll-like receptor 4 immune response in liver IRI. METHODS: Here, we focused on how PACAP suppressed hepatocellular damage and enhanced hepatocyte regeneration in a murine model of partial liver warm IRI. RESULTS: Yes-associated protein (YAP), a cellular modulator of tissue regeneration, was readily induced in wild type (WT) mouse IR-livers. As its induction was failed in PACAP-deficient livers, PACAP supplement enhanced YAP expression in WT mouse and promoted its nuclear translocation and downstream antioxidative/regenerative genes expression both in vivo and in vitro. Further, verteporfin, a YAP transcriptional inhibitor, abolished PACAP-mediated hepatoprotection significantly. Meanwhile, blockade of protein kinase A (PKA)-CRE-binding protein (CREB) signaling recreated liver damage in PACAP-protected liver as well as impeded stimulation on YAP and its downstream gene expressions. Consistently, inhibition of PKA-CREB decreased PACAP-promoted YAP expression in primary hepatocytes culture, and made them vulnerable to H2O2 stress in vitro. In addition, lysophosphatidic acid, another Hippo pathway inhibitor, failed to affect PACAP-mediated hepatoprotection or hepatocellular YAP induction. This implies that PACAP regulated YAP through PKA-CREB pathway at the transcriptional level rather than canonical hippo pathway. CONCLUSIONS: Our study discovered the neural modulation of PACAP-YAP axis in hepatic cytoprotection and homeostasis in liver IRI. These reveal a novel insight of neuropeptide PACAP in combating liver IRI in clinical patients.

Extended hepatectomy with segments I and VII as resection remnant: a simple model for small-for-size injuries in pigs.

BACKGROUND: Small-for-size (SFS) syndrome is an important clinical problem after living donor liver transplantation, split liver transplantation or extended hepatectomy. The uncertainty of the mechanisms and treatments of SFS syndrome urges surgeons to establish effective models for SFS syndrome. METHODS: A new porcine model for SFS syndrome based on extended hepatectomy was established. Portal pressure gradient was observed before and after the surgery, and venous sampling for estimation of alanine aminotransferase, total bilirubin, and international normalized ratio was continued on a daily basis. RESULTS: Although the external morphology of the porcine liver differs from that of human being, segmental anatomy is remarkably similar in term of its vascularity and biliary tree. Extended hepatectomy with segments I and VII as resection remnant (about 20% of total liver volume) resulted in similar survival rates, blood liver function tests, and elevated portal pressure gradient as clinical SFS syndrome. CONCLUSIONS: The extended hepatectomy based new model can easily be reproduced, with few costs and surgical complications. Clinical SFS syndrome can easily be simulated by this new model, which is a useful tool for studying SFS syndrome-related liver injuries, especially portal overperfusion and hypertension.

Partial Hepatectomy-Induced Upregulation of miR-1907 Accelerates Liver Regeneration by Activation Autophagy.

Liver regeneration after partial hepatectomy (PH) is a highly orchestrated biological process in which synchronized hepatocyte proliferation is induced after massive liver mass loss. Hepatocyte proliferation could be regulated by multiple signals, such as miRNAs and autophagy, but underlying mechanism remains unclear. Here a functional miRNA during liver regeneration was identified and its underlying mechanism was delineated in vitro and in vivo. We found that miR-1907 was highly upregulated during liver regeneration after 2/3 PH at various timepoints. The level of miR-1907 was also increased in normal liver cell line treated with HGF at different concentrations. Functionally, miR-1907 enhanced hepatocyte proliferation in vitro and in vivo, and the liver/body weight ratio in miR-1907-overexpressed mice was significantly higher in comparison to the control mice after 2/3 PH. Forced expression of miR-1907 promoted autophagy activation of hepatocyte. Importantly, autophagy inhibition significantly attenuated miR-1907-induced hepatocyte proliferation and the liver/body weight ratio. Finally, GSK3ß, a suppressor of autophagy signaling, was identified as the direct target gene of miR-1907. Taken together, miR-1907 accelerates hepatocyte proliferation during liver regeneration by activating autophagy; thus pharmacological intervention regulating miR-1907/autophagy axis may be therapeutically beneficial in liver transplantation and liver failure by inducing liver regeneration.

Dual Effect of Hepatic Macrophages on Liver Ischemia and Reperfusion Injury during Liver Transplantation.

Ischemia-reperfusion injury (IRI) is a major complication in liver transplantation (LT) and it is closely related to the recovery of grafts' function. Researches has verified that both innate and adaptive immune system are involved in the development of IRI and Kupffer cell (KC), the resident macrophages in the liver, play a pivotal role both in triggering and sustaining the sterile inflammation. Damage-associated molecular patterns (DAMPs), released by the initial dead cell because of the ischemia insult, firstly activate the KC through pattern recognition receptors (PRRs) such as toll-like receptors. Activated KCs is the dominant players in the IRI as it can secret various pro-inflammatory cytokines to exacerbate the injury and recruit other types of immune cells from the circulation. On the other hand, KCs can also serve in a contrary way to ameliorate IRI by upregulating the anti-inflammatory factors. Moreover, new standpoint has been put forward that KCs and macrophages from the circulation may function in different way to influence the inflammation. Managements towards KCs are expected to be the effective way to improve the IRI.

[Corrigendum] Farnesoid X receptor deletion improves cardiac function, structure and remodeling following myocardial infarction in mice.

Following the publication of this article, an interested reader drew to our attention that we had incorrectly reported (in the Materials and methods section, 'Western blot analysis', on p. 674) that the anti-farnesoid X receptor (FXR) antibody of Cell Signalling Technology, Inc., cat. no. #12295, had been used in this study to probe for FXR. In fact, the antibodies used in the above-mentioned study were a gift from the group of Dr Xin-Liang Ma at Thomas Jefferson University (Philadelphia, PA, USA), as referenced in the following article: [Pul J, Yuan A, Shan P, Gao E, Wang X, Wang Y, Lau WB, Koch W, Xin-Ma XL and He B: Cardiomyocyte-expressed farnesoid-X-receptor is a novel apoptosis mediator and contributes to myocardial ischaemia/reperfusion injury. Eur Heart J 34: 1834-1845, 2013]. The antibody that was used for the western blotting analysis was raised against the C-terminus of FXR (C-20; cat. no. sc-1204, Santa Cruz Biotechnology, San Diego, CA, USA). We sincerely apologize for this mistake, and thank the reader of our article who drew this matter to our attention. The error made in our incorrect referencing of the antibody did not affect the conclusions reported in this study. Furthermore, we regret the inconvenience that this mistake caused. [the original article was published in the Molecular Medicine Reports 16: 673-679, 2017; DOI: 10.3892/mmr.2017.6643].

Farnesoid X receptor deletion improves cardiac function, structure and remodeling following myocardial infarction in mice.

The farnesoid X receptor (FXR) is implicated in cholesterol and bile acid homeostasis; however, its role following myocardial infarction (MI) has yet to be elucidated. The aim of the present study was to investigate the effects of FXR knockout on left ventricular (LV) remodeling following MI. Coronary arteries of wild type (WT) and FXR­/­ mice were permanently occluded to cause MI, and serial echocardiographic and histological tests were conducted. At 4 weeks post­MI, FXR­/­ mice exhibited significantly smaller infarct sizes (34.20±2.58 vs. 44.20±3.19%), improved ejection fraction (47.31±1.08 vs. 37.64±0.75%) and reduced LV chamber dilation compared with WT mice. LV remodeling was significant as early as 7 days post­MI in FXR­/­ compared with WT mice. Histological features associated with enhanced long­term remodeling and improved functionality, such as increased angiogenesis via detection of CD31 and reduced fibrosis, were observed in the FXR­/­ group. Myocyte apoptosis within the infarcted zones appeared significantly reduced by day 7 in FXR­/­ mice. In conclusion, the results of the present study suggested that FXR knockout may participate in the preservation of post­MI cardiac functionality, via reducing fibrosis and chronic apoptosis, and ameliorating ventricular function.

Clinical prognostic significance of regional and extended lymphadenectomy for biliary cancer with para-aortic lymph node metastasis: A systematic review and meta-analysis.

BACKGROUND: The aim of our study was to evaluate clinical prognostic significance of regional and extended lymphadenectomy for biliary cancer with para-aortic lymph node metastasis. METHODS: A thorough literature search was performed in PubMed/Medline, Cochrane Central Register, Embase, ISI Web of Science and Google Scholar between January 1965 and May 2014 with restricted articles for the English language. Data were processed for a meta-analysis by RevMan 5 software. RESULTS: Altogether 10 retrospective studies were finally enrolled in our study. For positive para-aortic lymph node group irrespective of regional lymph node metastasis, the overall 1-, 3-, 5-yr pooled RR estimates of survival rates were 2.30, 1.70, and 1.42. There were significant differences between positive para-aortic lymph node group and negative group. For positive para-aortic lymph node group in the setting of regional lymph node metastasis, the overall 1-, 3-, 5-yr pooled RR estimates of survival rates were 1.57, 1.29, and 1.11, respectively. The long-term outcomes referred to 5-yr survival rate were similar between para-aortic lymph node metastasis and regional lymph node metastasis only. DISCUSSION: Radical resection with extended lymphadenectomy should be caution in terms of the results of an intraoperative sampling biopsy of para-aortic lymph node, which requires a well-designed, prospective controlled study in the future.

Inactivation of Sirt1 in mouse livers protects against endotoxemic liver injury by acetylating and activating NF-κB.

Sirtuin 1 (Sirt1) is a deacetylase that regulates many cellular processes in the liver, and so far its role in endotoxemic liver injury is elusive. So we conditionally inactivate Sirt1 in murine hepatocytes to determine its role in d-galactosamine (GalN)/lipopolysaccharide (LPS)-induced liver damage, which is a well-established experimental model mimicking septic liver injury and fulminant hepatitis. Ablation of Sirt1 shows remarkable protection against GalN/LPS-induced liver injury, which is a result of enhanced NF-κB response because knockdown of RelA/p65 negates the protective effect of Sirt1 knockout. Mechanistically, NF-κB p65 is maintained in a hyperacetylated, DNA-binding competent state in tumor necrosis factor-α (TNF-α)-challenged albumin-Cre+ (AlbCre+) hepatocytes. Transfection of hepatocytes with a recombinant acetylated p65 expression construct replicates the protection afforded by Sirt1 knockout. Transfection of AlbCre+ hepatocytes with a recombinant wild-type Sirt1 construct, rather than a deacetylase-defective one, compromises NF-κB activation and resensitizes hepatocytes to TNF-α-induced apoptosis. Taken together, our results demonstrate that Sirt1 deacetylates p65 and compromises NF-κB activity in hepatocytes when confronted with LPS/TNF-α stimulation, leading to increased susceptibility to endotoxemic injury. These findings identify a possible protein effector to maneuver the hepatic NF-κB signaling pathway under inflammatory circumstances and a feasible way to increase hepatocellular resistance to endotoxin/TNF-α toxicity.