Marcus Hollenbach

Curcumin inhibits glyoxalase 1: a possible link to its anti-inflammatory and anti-tumor activity.

Background Glyoxalases (Glo1 and Glo2) are involved in the glycolytic pathway by detoxifying the reactive methylglyoxal (MGO) into D-lactate in a two-step reaction using glutathione (GSH) as cofactor. Inhibitors of glyoxalases are considered as anti-inflammatory and anti-carcinogenic agents. The recent finding that various polyphenols modulate Glo1 activity has prompted us to assess curcumins potency as an Glo1 inhibitor. Methodology/Principal Findings Cultures of whole blood cells and tumor cell lines (PC-3, JIM-1, MDA-MD 231 and 1321N1) were set up to investigate the effect of selected polyphenols, including curcumin, on the LPS-induced cytokine production (cytometric bead-based array), cell proliferation (WST-1 assay), cytosolic Glo1 and Glo2 enzymatic activity, apoptosis/necrosis (annexin V-FITC/propidium iodide staining; flow cytometric analysis) as well as GSH and ATP content. Results of enzyme kinetics revealed that curcumin, compared to the polyphenols quercetin, myricetin, kaempferol, luteolin and rutin, elicited a stronger competitive inhibitory effect on Glo1 (Kiu200a=u200a5.1±1.4 µM). Applying a whole blood assay, IC50 values of pro-inflammatory cytokine release (TNF-α, IL-6, IL-8, IL-1β) were found to be positively correlated with the Ki-values of the aforementioned polyphenols. Moreover, whereas curcumin was found to hamper the growth of breast cancer (JIMT-1, MDA-MB-231), prostate cancer PC-3 and brain astrocytoma 1321N1 cells, no effect on growth or vitality of human primary hepatocytes was elucidated. Curcumin decreased D-lactate release by tumor cells, another clue for inhibition of intracellular Glo1. Conclusions/Significance The results described herein provide new insights into curcumins biological activities as they indicate that inhibition of Glo1 by curcumin may result in non-tolerable levels of MGO and GSH, which, in turn, modulate various metabolic cellular pathways including depletion of cellular ATP and GSH content. This may account for curcumins potency as an anti-inflammatory and anti-tumor agent. The findings support the use of curcumin as a potential therapeutic agent.

Ethyl pyruvate and ethyl lactate down-regulate the production of pro-inflammatory cytokines and modulate expression of immune receptors

Esters of alpha-oxo-carbonic acids such as ethyl pyruvate (EP) have been demonstrated to exert inhibitory effects on the production of anti-inflammatory cytokines. So far, there is no information about effects, if any, of ethyl lactate (EL), an obviously inactive analogue of EP, on inflammatory immune responses. In the present study, we provide evidence that the anti-inflammatory action of alpha-oxo-carbonic acid esters is mediated by inhibition of glyoxalases (Glo), cytosolic enzymes that catalyse the conversion of alpha-oxo-aldehydes such as methylglyoxal (MGO) into the corresponding alpha-hydroxy acids using glutathione as a cofactor. In vitro enzyme activity measurements revealed the inhibition of human Glo1 by alpha-oxo-carbonic acid esters, whilst alpha-hydroxy-carbonic acid esters such as EL were not inhibitory. In contrast, both EP and EL were shown to suppress the Lipopolysaccharide (LPS)-induced production of pro-inflammatory cytokines such as tumor necrosis factor-alpha, interleukin (IL)-1beta, IL-6 and IL-8 from human immunocompetent cells, and modulated the expression of the immune receptors HLA-DR, CD14 and CD91 on human monocytes. Here, we show a crossing link between glyoxalases and the immune system. The results described herein introduce glyoxalases as a possible target for therapeutic approaches of immune suppression.

Stepwise diagnosis in covert hepatic encephalopathy: critical flicker frequency and MELD-score as a first-step approach.

The diagnosis of covert hepatic encephalopathy (CHE) by means of portosystemic encephalopathy syndrome (PSE) test is costly and therefore infrequently performed.

Genome-wide association study identifies inversion in the CTRB1-CTRB2 locus to modify risk for alcoholic and non-alcoholic chronic pancreatitis

Objective Alcohol-related pancreatitis is associated with a disproportionately large number of hospitalisations among GI disorders. Despite its clinical importance, genetic susceptibility to alcoholic chronic pancreatitis (CP) is poorly characterised. To identify risk genes for alcoholic CP and to evaluate their relevance in non-alcoholic CP, we performed a genome-wide association study and functional characterisation of a new pancreatitis locus. Design 1959 European alcoholic CP patients and population-based controls from the KORA, LIFE and INCIPE studies (n=4708) as well as chronic alcoholics from the GESGA consortium (n=1332) were screened with Illumina technology. For replication, three European cohorts comprising 1650 patients with non-alcoholic CP and 6695 controls originating from the same countries were used. Results We replicated previously reported risk loci CLDN2-MORC4, CTRC, PRSS1-PRSS2 and SPINK1 in alcoholic CP patients. We identified CTRB1-CTRB2 (chymotrypsin B1 and B2) as a new risk locus with lead single-nucleotide polymorphism (SNP) rs8055167 (OR 1.35, 95% CI 1.23 to 1.6). We found that a 16.6u2009kb inversion in the CTRB1-CTRB2 locus was in linkage disequilibrium with the CP-associated SNPs and was best tagged by rs8048956. The association was replicated in three independent European non-alcoholic CP cohorts of 1650 patients and 6695 controls (OR 1.62, 95%u2009CI 1.42 to 1.86). The inversion changes the expression ratio of the CTRB1 and CTRB2 isoforms and thereby affects protective trypsinogen degradation and ultimately pancreatitis risk. Conclusion An inversion in the CTRB1-CTRB2 locus modifies risk for alcoholic and non-alcoholic CP indicating that common pathomechanisms are involved in these inflammatory disorders.

Serum Ferritin in Patients With Cirrhosis is Associated With Markers of Liver Insufficiency and Circulatory Dysfunction, but Not of Portal Hypertension.

Background/Aims: Iron overload is an increasingly recognized phenomenon in nonhemochromatosis cirrhosis. To evaluate the relationship between iron overload and liver insufficiency and portal hypertension. Patients and Methods: Cirrhotics with hepatic hemodynamic and ferritin measurement (within 30 d) were included. Exclusion criteria were malignancy (except hepatocellular carcinoma Milan-in), severe chronic obstructive pulmonary disease, acute events in the previous 2 weeks, immunosuppression, transjugular intrahepatic portosystemic shunt or portal vein thrombosis, and end-stage renal disease. Patients were followed-up until death or liver transplant. Univariate and multivariate analysis were used. Results: Fifty-one patients were included (male 61%; median age 57 y; interquartile range, 47 to 66 y); Child-Pugh A 11/B 25/C 15). A positive correlation was observed between ferritin and markers of inflammation (C-reactive protein: r=0.273, P=0.06 and aspartate aminotransferase: r=0.302, P=0.035). No correlation between ferritin and hepatic venous pressure gradient was seen. Negative correlations were observed between ferritin and circulatory dysfunction (mean arterial pressure: r=−0.360, P=0.014 and serum sodium: r=−0.419, P=0.002). In contrast, associations to markers of liver failure such as international normalized ratio (r=0.333, P=0.005), bilirubin (r=0.378, P=0.007), albumin (r=−0.265, P=0.082), model for end-stage liver disease (r=0.293, P=0.041), and Child-Pugh score (r=0.392, P=0.009) were observed. No differences in survival according to ferritin was detected. Conclusions: In patients with cirrhosis, serum ferritin levels are associated with markers of liver insufficiency, inflammation, and circulatory dysfunction but not portal hypertension.

Common variants in the CLDN2-MORC4 and PRSS1-PRSS2 loci confer susceptibility to acute pancreatitis

BACKGROUND/OBJECTIVESnAcute pancreatitis (AP) is one of the most common gastrointestinal disorders often requiring hospitalization. Frequent aetiologies are gallstones and alcohol abuse. In contrast to chronic pancreatitis (CP) few robust genetic associations have been described. Here we analysed whether common variants in the CLDN2-MORC4 and the PRSS1-PRSS2 locus that increase recurrent AP and CP risk associate with AP.nnnMETHODSnWe screened 1462 AP patients and 3999 controls with melting curve analysis for SNPs rs10273639 (PRSS1-PRSS2), rs7057398 (RIPPLY), and rs12688220 (MORC4). Calculations were performed for the overall group, aetiology, and gender sub-groups. To examine genotype-phenotype relationships we performed several meta-analyses.nnnRESULTSnMeta-analyses of all AP patients depicted significant (p-valueu202f<u202f0.05) associations for rs10273639 (odds ratio (OR) 0.88, 95% confidence interval (CI) 0.81-0.97, p-value 0.01), rs7057398 (OR 1.27, 95% CI 1.07-1.5, p-value 0.005), and rs12688220 (OR 1.32, 95% CI 1.12-1.56, p-value 0.001). For the different aetiology groups a significant association was shown for rs10273639 (OR 0.76, 95% CI 0.63-0.92, p-value 0.005), rs7057398 (OR 1.43, 95% CI 1.07-1.92, p-value 0.02), and rs12688220 (OR 1.44, 95% CI 1.07-1.93, p-value 0.02) in the alcoholic sub-group only.nnnCONCLUSIONSnThe association of CP risk variants with different AP aetiologies, which is strongest in the alcoholic AP group, might implicate common pathomechanisms most likely between alcoholic AP and CP.

The Role of Glyoxalase-I in Oxidant Stress of Liver Damage

Abstract Glyoxalase-I (Glo-I) is the main detoxifying enzyme for methylglyoxal (MGO) leading to the formation of advanced glycation endproducts (AGEs) and oxidative stress. AGEs bind to their receptor RAGE and activate intracellular transcription factors and inflammation. While data of Glo-I and MGO in liver disease are preliminary, AGEs and RAGE are involved in liver fibrosis and inflammation. AGEs increase α-SMA, collagen deposit, and oxidative stress in inflammatory liver disease.

Plasma mSEPT9: A Novel Circulating Cell-free DNA-Based Epigenetic Biomarker to Diagnose Hepatocellular Carcinoma

Summary Background Patients with cirrhosis are at high risk of hepatocellular carcinoma (HCC). The SEPT9 gene is a key regulator of cell division and tumor suppressor whose hypermethylation is associated with liver carcinogenesis. The primary aim of this study was to evaluate the diagnostic accuracy of a PCR-based assay for the analysis of SEPT9 promoter methylation in circulating cell-free DNA (mSEPT9) for diagnosing HCC among cirrhotic patients. Methods We report two phase II biomarker studies that included cirrhotic patients with or without HCC from France (initial study) and Germany (replication study). All patients received clinical and biological evaluations, and liver imaging according to current recommendations. The primary outcome was defined as the presence of HCC according to guidelines from the American Association for the Study of Liver Diseases. The diagnosis of HCC was confirmed by abdominal contrast-enhanced computed tomography scan and systematically discussed in a multidisciplinary consultation meeting. HCC-free cirrhotic patients were recruited if the screening abdominal ultrasound showed no evidence of HCC at the time of blood sampling for the mSEPT9 test and on the next visit six months later. The adjudicating physicians were blinded to patient results associated with the mSEPT9 test. Findings We included 289 patients with cirrhosis (initial: 186; replication: 103), among whom 98 had HCC (initial: 51; replication: 47). The mSEPT9 test exhibited high diagnostic accuracy for HCC diagnosis, with an area under the receiver operating characteristic curve (AUROC) of 0.944 (0.900–0.970, p < 0.0001) in the initial study (replication: 0.930 [0.862–0.971, p < 0.0001]; meta-analysis: AUROC = 0.940 [0.910–0.970, p < 0.0001], no heterogeneity: I2 = 0%, p = 0.67; and no publication bias). In multivariate logistic regression analysis, the number of positive mSEPT9 triplicates was the only independent variable significantly associated with HCC diagnosis (initial: OR = 6.30, for each mSEPT9 positive triplicate [2.92–13.61, p < 0.0001]; replication: OR = 6.07 [3.25–11.35, p < 0.0001]; meta-analysis: OR = 6.15 [2.93–9.38, p < 0.0001], no heterogeneity: I2 = 0%, p = 0.95; no publication bias). AUROC associated with the discrimination of the logistic regression models in initial and validation studies were 0.969 (0.930–0.989) and 0.942 (0.878–0.978), respectively, with a pooled AUROC of 0.962 ([0.937–0.987, p < 0.0001], no heterogeneity: I2 = 0%, p = 0.36; and no publication bias). Interpretation Among patients with cirrhosis, the mSEPT9 test constitutes a promising circulating epigenetic biomarker for HCC diagnosis at the individual patient level. Future prospective studies should assess the mSEPT9 test in the screening algorithm for cirrhotic patients to improve risk prediction and personalized therapeutic management of HCC.

Analysis of Wire-Guided Hemostasis Introducer for Percutaneous Therapy of Bile Duct Stones

Background: Bile duct stones (BDS) are usually removed via endoscopic retrograde cholangiopancreatography (ERCP) or, if ERCP remains unsuccessful, percutaneous transhepatic cholangiodrainage (PTCD). However, PTCD provides limited access to large BDSs. We analyzed a modified approach of PTCD for percutaneous therapy of BDS. Methods: We used a modified approach of PTCD with a 13-french (Fr) hemostasis introducer for transhepatic access to BDS. Short-wired balloon or basket catheter were applied for safe removal of BDS. Patient characteristics, effectiveness, and complications were analyzed. Results: We identified 11 patients who underwent PTCD with hemostasis introducer. BDSs were either pushed forward to the duodenum (36%) or both partly pushed and extracted via hemostasis introducer (64%). In some cases, mechanical lithotripsy was necessary (45%). Complete removal of BDS was initially achieved in 36% of patients, 45% received additional PTCD, and in 19% stent implantation was performed. Finally, all BDSs could be removed. Laboratory analysis revealed significant reduction of alkaline phosphatase (p = 0.03) and C reactive protein (p = 0.03). Complications occurred only in 1 patient with post-interventional cholangitis. Conclusion: Our study showed feasibility and safety of a modified PTCD with hemostasis introducer. In addition, protection of liver tissue from sharp-edged catheters and stones was achieved. Therefore, our modification revealed an innovational approach for transhepatic removal of BDS.

Design of the Weight-loss Endoscopy Trial (WET): a multi-center, randomized, controlled trial comparing weight loss in endoscopically implanted duodenal-jejunal bypass liners vs. intragastric balloons vs. a sham procedure

BackgroundObesity is a global problem leading to reduced life expectancy, cardiovascular diseases, diabetes and many types of cancer. Even people willing to accept treatment only achieve a mean weight loss of about 5xa0kg using commercial weight loss programs. Surgical interventions, e.g. sleeve gastrectomy or gastric bypass are effective but accompanied by risk of serious complications and side effects. Less invasive endoscopic procedures mainly comprise the intragastric balloon (IB) and the duodenal-jejunal bypass liner (DJBL). To date, a randomized comparison between these devices has not been undertaken or shown to be superior to a sham procedure.MethodsWe designed a multi-center, randomized, patient and assessor-blinded, controlled trial comparing weight loss in endoscopically implanted IB vs. DJBL vs. a sham procedure. A total of 150 patients with a BMIu2009>u200935xa0kg/m2 oru2009>u200930 with obesity-related comorbidities and indication for proton pump inhibitors are randomized to receive either IB, DJBL or a sham gastroscopy (2:2:1 ratio). All participants undergo regular dietary consultation. The IB will be removed after 6xa0months, whereas the DJBL will be explanted after 12xa0months. All patients will receive gastroscopies at implantation and explantation of the devices or sedation without gastroscopy to maintain blinding. Main exclusion criteria are malignant diseases, peptic ulcer or previous bariatric intervention. Weight loss 12xa0months after explantation of the devices, changes in comorbidities, quality of life, complication rates and safety will be evaluated.DiscussionThis trial could help to identify the most effective and safest endoscopic device, thus determining the new standard procedure for endoscopic bariatric treatment.Trial registration16th January 2017. DRKS00011036. Funded by the German Research Foundation (DFG).