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Identification of patients at risk of a complicated course after liver resection is crucial for adapting post-operative care. In the present study, we investigated the diagnostic value of the plasma levels of various cytokines obtained immediately after surgery. IL-6, IL-10, IL-8, monokine induced by interferon-γ (MIG), monocyte chemotactic protein-1 (MCP-1) and interferon-inducible protein-10 (IP-10) concentrations were measured in 26 patients after liver resection using a cytometric bead assay and were correlated with liver function, resectate weight, surgery duration, ischemia/reperfusion, hospitalization time and occurrence of complications. Patients with post-surgical complications showed distinctive patterns of IL-6 and IL-8 as early as minutes to hours after surgery. In addition, although pre-operative bilirubin in most patients remained within the normal range, a cut-off of 1 mg/dl separated the patients into groups with different profiles of IL-6, IL-8, and MCP-1 secretion and different likelihoods of experiencing post-operative complications (bilirubin levels ≥1.0 vs. <1.0 mg/dl; IL-6 (4 h): 701 vs. 265; IL-8 (6 h): 262 vs. 97 pg/ml; p<0.05 for both). Extended hospitalization, related to delayed recovery, was correlated with increased IL-8 and MCP-1 immediately after surgery. In conclusion, on the basis of these observations, we suggest that early measurement of post-operative levels of MCP-1, IL-6, and IL-8 can be used to identify individuals at risk of post-operative complications immediately after liver surgery.

Valproate (VPA) is a well-characterized histone deacetylase inhibitor with anti-neoplastic properties. We analyzed the growth blocking effects and the molecular mode of action of this compound in colorectal cancer cells in vitro and in vivo. Caco-2, SW-480, CX-1 or WIDR cell lines were exposed to VPA (0.25-2 mM) for various time periods. Cell growth, cell cycle progression and apoptosis were analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide dye reduction assay and flow cytometry. Cell cycle- and apoptosis-regulating proteins and histone acetylation were assessed by Western blotting. In vivo tumor growth and regulating protein expression under VPA were investigated in a subcutaneous xenograft tumor model. VPA inhibited the growth of all cell lines with cell cycle arrest paralleled by the up-regulation of H3 and H4 acetylation. In vivo tumor growth was substantially depressed by VPA (200 mg/kg bw). Cell cycle proteins (cdk1, cdk2, cdk4, cyclin D, cyclin E, p19, p21 and p27) were differentially altered by VPA. Predominantly cdk1 was decreased and p27 was up-regulated in all models. Apoptosis-related proteins were altered in vivo with up-regulation of bax and down-regulation of bcl-2. VPA exerts anti-neoplastic activity in colorectal tumor cell lines in vitro and in vivo by altering cell cycle regulation.

Protective hepatocellular responses to a hypoxic challenge are crucial to preserve liver function. The knowledge of affected metabolic functions could help assess and enhance hepatic ischemic tolerance. Here we studied adaptive mechanisms in human hepatocytes after hypoxia and reoxygenation using a proteomic approach. Proteins from primary hepatocytes were extracted after 6 h of hypoxia and 24 h of reoxygenation. The proteome was analyzed by 2D-electrophoresis. Densitometry and mass spectrometry (MALDI-TOF-MS) were used for protein identification. Two hundred and sixty-two spots were differentially analyzed and 33 spots displayed significant differences between hypoxic and normoxic cells. Seventeen proteins were identified by mass spectrometry. After hypoxia and reoxygenation the UTP-glucose-1-phosphate uridyltransferase, phosphoglycerate kinase1, fructose-1,6-bisphosphate aldolase, glyceraldehyde-3-phosphate dehydrogenase, fructose-1,6-bisphosphatase, thiosulfat-sulfurtransferase, thioredoxin peroxidase, peroxiredoxin III, and annexin A2 proteins were down-regulated. An increased expression was found for carbamoyl phosphate synthetase I, heat shock 70 kDa protein5, phosphoenolpyruvate carboxy-kinase, catalase isoform2, peroxiredoxin II, glutathione S-transferase, hydroxyacid oxidase1, and F1-ATP synthase, alpha subunit1. Hepatocellular adaptation to hypoxia and reoxygenation involve glucose metabolism, peroxisomal functions, and oxidative stress protection. The identified proteins can serve as possible diagnostic targets to monitor hepatic hypoxic tolerance e.g. in the context of liver surgery and transplantation.

Complement effectors are known to contribute to host cell injury in several inflammatory diseases. Contrary to this paradigm, in this study utilizing surgical liver resection (partial hepatectomy) in various complement-deficient mice as a model, we have demonstrated that complement anaphylatoxins C3a and C5a are required for the survival of liver cells during regeneration. The mechanisms of these cytoprotective functions of complement were related to the regulation of IL-6 and TNF production or release after liver resection. Disturbances in the cytokine milieu, induced by a loss of complement activity, were found to alter prosurvival signaling, including the IL-6/STAT3 and PI3K/Akt/mammalian target of rapamycin pathways. In conclusion, this study documents functions of complement proteins as prosurvival factors that, through their interactions with cytokines, inhibit apoptotic signaling in proliferating cells of epithelial origin.

Acceleration of liver regeneration could be of great clinical benefit in various liver-associated diseases. However, at present little is known about therapeutic interventions to enhance this regenerative process. Our limited understanding and the complexity of the mechanisms involved have prevented the identification of new targets for treatment. Here we propose a broad-range proteomic approach to this problem that makes possible the simultaneous study of different signaling and metabolic pathways on the liver proteome. Changes in protein expression in mouse livers (n = 5 per group) at 6 h and 12 h after partial hepatectomy and sham operation, as compared to untreated controls, were analyzed using two-dimensional gel electrophoresis, mass spectrometry (MS), and mass fingerprinting. Twelve proteins, identified by MS, were up-regulated by at least 2-fold after partial hepatectomy. These included adipose differentiation-related protein, gamma-actin, enoyl coenzyme A hydratase 1, serum amyloid A and eukaryotic translation initiation factor 3. These results indicate that liver regeneration following partial hepatectomy affects various signaling and metabolic pathways.

Although the complement system has been implicated in liver regeneration after toxic injury and partial hepatectomy, the mechanism or mechanisms through which it participates in these processes remains ill-defined. In this study, we demonstrate that complement activation products (C3a, C3b/iC3b) are generated in the serum of experimental mice after CCl(4) injection and that complement activation is required for normal liver regeneration. Decomplementation by cobra venom factor resulted in impaired entry of hepatocytes into S phase of the cell cycle. In addition, livers from C3-deficient (C3(-/-)) mice showed similarly impaired proliferation of hepatocytes, along with delayed kinetics of both hepatocyte hyperplasia and removal of injured liver parenchyma. Restoration of hepatocyte proliferative capabilities of C3(-/-) mice through C3a reconstitution, as well as the impaired regeneration of C3a receptor-deficient mice, demonstrated that C3a promotes liver cell proliferation via the C3a receptor. These findings, together with data showing two waves of complement activation, indicate that C3 activation is a pivotal mechanism for liver regeneration after CCl(4) injury, which fulfills multiple roles; C3a generated early after toxin injection is relevant during the priming of hepatocytes, whereas C3 activation at later times after CCl(4) treatment contributes to the clearance of injured tissue.

Background: Aspirin treatment has an undoubted beneficial impact on the progression of cardiovascular diseases. We hypothesized that aspirin also protects allograft function and survival in the context of chronic renal allograft dysfunction, which displays decisive pathophysiologic features that are similar to those involved in atherogenesis., Methods: A retrospective, multivariate analysis was performed to assess the effect of low-dose aspirin treatment (100 mg/day) on allograft function and survival of 830 renal transplant recipients. Allograft function was evaluated by serum creatinine levels, urine protein levels, and the presence of hematuria., Results: Median allograft survival time was significantly longer in patients receiving low-dose aspirin therapy compared with patients receiving no aspirin treatment (n=205, 13.8 +/- 2.6 vs. 7.8 +/- 0.3 years, n=625; adjusted relative risk=0.443, 95% confidence interval [0.323-0.608], P<0.0001). Statin treatment and a recent time point of transplantation, reflecting the qualitative advances of the applied immunosuppressive therapy, were further positive determinants of renal allograft survival. The number of antihypertensive agents, representing the extent of hypertension, was a negative determinant of allograft survival. Transplant function was better preserved in aspirin-treated patients, who displayed a slower increase of serum creatinine and less proteinuria and hematuria during the observation period. The duration of aspirin treatment was positively associated with better allograft function., Conclusions: Low-dose aspirin therapy substantially improves renal allograft function and allograft survival. These findings suggest that aspirin should be considered to complement long-term posttransplant medical treatment regimens.

Complement has been implicated in liver repair after toxic injury. Here, we demonstrate that complement components are essential for liver regeneration, and mediate their effect by interacting with key signaling networks that promote hepatocyte proliferation. C3- or C5-deficient mice exhibited high mortality, parenchymal damage, and impaired liver regeneration after partial hepatectomy. Mice with dual C3 and C5 deficiency had a more exacerbated phenotype that was reversed by combined C3a and C5a reconstitution. Interception of C5a receptor signaling resulted in suppression of IL-6/TNFalpha induction and lack of C3 and C5a receptor stimulation attenuated nuclear factor-kappaB/STAT-3 activation after hepatectomy. These data indicate that C3a and C5a, two potent inflammatory mediators of the innate immune response, contribute essentially to the early priming stages of hepatocyte regeneration.