Potential impact of trained innate immunity on the pathophysiology of metabolic dysfunction-associated fatty liver disease.

Metabolic dysfunction-associated fatty liver disease (MAFLD) occurs in a low-grade inflammatory milieu dependent on highly complex networks that span well-beyond the hepatic tissue injury. Dysfunctional systemic metabolism that characterizes the disease, is further induced in response to environmental cues that modify energy and metabolic cellular demands, thereby altering the availability of specific substrates that profoundly regulate, through epigenetic mechanisms, the phenotypic heterogeneity of immune cells and influence hematopoietic stem cell differentiation fate. This immuno-metabolic signaling drives the initiation of downstream effector pathways and results in the decompensation of hepatic homeostasis that precedes pro-fibrotic events. Recent evidence suggests that innate immune cells reside in different tissues in a memory effector state, a phenomenon termed trained immunity, that may be activated by subsequent exogenous (e.g., microbial, dietary) or endogenous (e.g., metabolic, apoptotic) stmuli. This process leads to long-term modifications in the epigenetic landscape that ultimately precondition the cells towards enhanced transcription of inflammatory mediators that accelerates MAFLD development and/or progression. In this mini review we aimed to present current evidence on the potential impact of trained immunity on the pathophysiology of MAFLD, shedding light on the complex immunobiology of the disease and providing novel potential therapeutic strategies to restrain the burden of the disease.

Controlling the Impact of Helicobacter pylori-Related Hyperhomocysteinemia on Neurodegeneration.

Helicobacter pylori infection consists a high global burden affecting more than 50% of the world's population. It is implicated, beyond substantiated local gastric pathologies, i.e., peptic ulcers and gastric cancer, in the pathophysiology of several neurodegenerative disorders, mainly by inducing hyperhomocysteinemia-related brain cortical thinning (BCT). BCT has been advocated as a possible biomarker associated with neurodegenerative central nervous system disorders such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, and/or glaucoma, termed as "ocular Alzheimer's disease". According to the infection hypothesis in relation to neurodegeneration, Helicobacter pylori as non-commensal gut microbiome has been advocated as trigger and/or mediator of neurodegenerative diseases, such as the development of Alzheimer's disease. Among others, Helicobacter pylori-related inflammatory mediators, defensins, autophagy, vitamin D, dietary factors, role of probiotics, and some pathogenetic considerations including relevant involved genes are discussed within this opinion article. In conclusion, by controlling the impact of Helicobacter pylori-related hyperhomocysteinemia on neurodegenerative disorders might offer benefits, and additional research is warranted to clarify this crucial topic currently representing a major worldwide burden.

Vaspin, resistin, retinol-binding protein-4, interleukin-1α and interleukin-6 in patients with nonalcoholic fatty liver disease.

UNLABELLED:  Background and rational. Data on newer adipokines and interleukins in patients with nonalcoholic fatty liver disease (NAFLD) are inconclusive. The primary aim of this study was the evaluation of serum vaspin, resistin, retinol-binding protein (RBP)-4, interleukin (IL)-1α and IL-6 levels in NAFLD patients compared to matched controls, and their association with disease severity. MATERIAL AND METHODS: Twenty-nine consecutively enrolled NAFLD patients with histologically confirmed nonalcoholic simple steatosis (SS; n = 15) or steatohepatitis (NASH; n = 14) and 25 matched controls without NAFLD were recruited. Serum vaspin, resistin, RBP-4, IL-1α and IL-6 and biochemical tests were measured. RESULTS: Serum vaspin levels were lower and IL-6 levels higher in NASH patients than controls, but similar between controls and SS patients, or NASH and SS patients (vaspin, controls: 728.5 ± 39.3; SS: 634.6 ± 63.7; NASH: 531.5 ± 52.0 pg/mL; p for trend 0.028; IL-6, controls: 1.5 ± 0.2; SS: 2.5 ± 0.6; NASH: 3.0 ± 0.6 pg/mL; p for trend 0.032). However, after adjustment for body mass index or waist circumference, both vaspin and IL-6 did not remain significantly different between groups. Resistin, RBP-4 and IL-1α were not statistically different between groups. None of the selected adipokines or interleukins could independently differentiate NAFLD from SS, or patients with more severe from less severe histological lesions. CONCLUSION: Lower circulating vaspin, but higher IL-6 levels were observed in NASH patients than controls, whereas resistin, RBP-4 and IL-1α levels were similar between groups. However, these differences did not remain robust after adjustment for body mass index or waist circumference.

The role of capsule endoscopy in the evaluation and treatment of obscure-overt gastrointestinal bleeding during daily clinical practice: a prospective multicenter study.

OBJECTIVE: Capsule endoscopy (CE) is most commonly performed to evaluate obscure gastrointestinal bleeding (GIB). However, at present the role of CE in patients with obscure-overt GIB especially during daily clinical practice is unknown. The aim of the present study was to investigate the diagnostic yield and the impact of CE on the management of patients with obscure-overt GIB. MATERIAL AND METHODS: Between January 2007 and December 2011 we prospectively included all patients with obscure-overt GIB who underwent CE after negative bidirectional endoscopy. CE findings revealing the cause of bleeding, type of therapeutic intervention and clinical variables associated with positive CE and recurrence of GIB were evaluated. RESULTS: One hundred and eighteen patients with a median age of 66 years (range 8-89 years) were enrolled in the final analysis. The overall diagnostic yield of the CE was 66.9%. The most common findings were angiodysplasias (33.1%), followed by ulcer (23.7%), and tumors (6.8%). Age (p = 0.001) and cardiovascular disease (p = 0.007) were significant clinical variables predicting the higher incidence of angiodysplasias. Specific therapeutic interventions were undertaken in 54 patients with positive CE (68.4%). Recurrence of GIB was observed in one patient with negative CE (2.6%) and 16 patients with positive CE (20.3%). Univariate and multivariate analysis showed high age and no therapeutic intervention as significant factors associated with recurrent bleeding. CONCLUSIONS: CE represents a promising diagnostic method in the investigation of obscure-overt GIB, with significant impact on its clinical management in daily clinical practice.

Fibrin glue and coats compromise the integrity of colonic anastomosis: an experimental trial on rats.

Background: Anastomotic leak remains a dreaded complication in colorectal surgery. Identifying optimal techniques that minimize its incidence is an active area of investigation. The aim of this experimental study was to evaluate the effect of commonly used hemostatic products on the integrity of colonic anastomoses. Methods: Male Wistar rats were randomized into 4 groups. In the control group (A), the anastomosis was performed using the standard hand-sewn technique in the ascending colon. In group B the hand-sewn technique was reinforced with a collagen-fibrinogen patch, in group C with fibrin glue, and in group D with a polyethylene glycol (PEG)-coated oxidized cellulose patch. On the 7th postoperative day, anastomotic bursting pressure measurements were obtained. A specimen surrounding the anastomosis was retrieved for histopathologic evaluation. Results: Of the 19 rats, 17 survived and 15 were included in the analysis (5 in each of groups A, B and C). Testing in group D was discontinued following adverse events in the preliminary experiments. The mean bursting pressure of the anastomosis was significantly higher in the control group (A: 221±19.41 mmHg, B: 151±14.42 mmHg, and C: 112±13.57 mmHg; P=0.001). Anastomotic healing parameters were not different between groups. Conclusions: Although experimental data support the use of sealants in defective anastomoses, in this study the reinforcement of colonic anastomosis with fibrin or oxidized cellulose-PEG sealants did not improve either bursting pressure values or anastomotic healing. More data from robust anastomoses of animals and humans are needed before sealing becomes common clinical practice in colorectal surgery.

A novel noninvasive index for nonalcoholic steatohepatitis: a pilot study.

OBJECTIVE: The potential development of a noninvasive marker predicting nonalcoholic steatohepatitis (NASH). METHODS: Thirty patients with biopsy-proven nonalcoholic fatty liver disease were evaluated by numerous anthropometric, clinical and biochemical parameters. RESULTS: Serum glutamic oxaloacetic transaminase (SGOT; p = 0.027), log (erythrocyte sedimentation rate) (ESR; p = 0.034) and homocysteine (p = 0.041) were associated with NASH independently from gender, age and body mass index. When combined, the regression model provided R(2) = 0.563 (p = 0.001) and area under the ROC curve = 0.873 ± 0.066 (p < 0.001). CONCLUSION: This noninvasive marker, named HSENSI (acronym of homocysteine, SGOT, ESR, Nonalcoholic Steatohepatitis Index), consists of three low cost, easily measurable parameters and may accurately predict NASH.

Increased fracture risk assessed by fracture risk assessment tool in Greek patients with Crohn's disease.

BACKGROUND: The World Health Organization has recently developed the fracture risk assessment tool (FRAX) based on clinical risk factors and bone mineral density (BMD) for evaluation of the 10-year probability of a hip or a major osteoporotic fracture. The aim of this study was to evaluate the use of the FRAX tool in Greek patients with inflammatory bowel disease (IBD). METHODS: FRAX scores were applied to 134 IBD patients [68 Crohn's disease (CD); 66 ulcerative colitis (UC)] who underwent dual-energy X-ray absorptiometry scans at the femoral neck and lumbar spine during the period 2007-2012. Calculation of the FRAX scores, with or without BMD, was made through a web-based probability model used to compute individual fracture probabilities according to specific clinical risk factors. RESULTS: The median 10-year probability of a major osteoporotic fracture for IBD patients based on clinical data was 7.1%, and including the BMD was 6.2%. A significant overestimation with the first method was found (P = 0.01). Both scores with and without BMD were significantly higher in CD patients compared with UC patients (P = 0.02 and P = 0.005, respectively). The median 10-year probability of hip fracture based on clinical data was 0.8%, and including the BMD was 0.9%. The score with use of BMD was significantly higher in CD compared with UC patients (P = 0.04). CONCLUSIONS: CD patients have significantly higher FRAX scores and possibly fracture risk compared with UC patients. The clinical FRAX score alone seems to overestimate the risk of osteoporotic fracture in Greek IBD patients.

Adipocytokines and cytokeratin-18 in patients with nonalcoholic fatty liver disease: Introduction of CHA index.

BACKGROUND AND RATIONALE: Insulin resistance (IR), adipocytokines, oxidative stress and hepatic apoptosis play a pathogenetic role in nonalcoholic fatty liver disease (NAFLD). AIMS: The evaluation of specific adipocytokines and markers of IR, oxidative stress and apoptosis in NAFLD patients; the introduction of a combined non-invasive index for nonalcoholic steatohepatitis (NASH). MATERIAL AND METHODS: Thirty patients with biopsy-proven NAFLD (15 with simple nonalcoholic fatty liver [NAFL], 15 with NASH) and 24 controls were recruited. Blood samples for total and high molecular weight (HMW) adiponectin, visfatin and tumor necrosis factor (TNF)-α, the apoptotic by-product cytokeratin (CK)-18, the reactive oxygen metabolites (ROMs) and standard biochemical tests were measured. Homeostatic model of assessment - insulin resistance (HOMA-IR) and quantitative insulin sensitivity check index (QUICKI) were calculated. MAIN RESULTS: Total and HMW adiponectin were significantly lower and TNF-α higher in either NAFL or NASH group compared to control group; CK-18 was significantly higher in NASH compared to either NAFL or control group. CHAI (an acronym of CK-18, HOMA-IR, AST Index) was calculated as the product of parameters being significantly different between NAFL and NASH groups. CHAI was significantly higher in NASH (24.2 [15.1-214.0]) compared to either NAFL (15.7 [6.8-22.7]) or control (5.1 [2.4-7.6]) group (p < 0.001) and significantly higher as the severity of steatosis, fibrosis, ballooning, lobular and portal inflammation advanced. CONCLUSION: CHAI was escalating from controls to NAFL and NASH and was higher by increasing the severity of all the main histological lesions. However, a validation study is needed before introducing CHAI in clinical practice.

Impact of periampullary diverticula on the outcome and fluoroscopy time in endoscopic retrograde cholangiopancreatography.

BACKGROUND: It is unclear whether the presence of periampullary diverticula (PAD) affects technical success and complication rates during endoscopic retrograde cholangiopancreatography (ERCP). Moreover, the impact of PAD on fluoroscopy duration is still unknown. The present study aimed to investigate the success rate and difficulty of common bile duct (CBD) cannulation, post-procedure complications and fluoroscopy duration in patients with and without PAD. METHODS: Patients from January 2008 to December 2010 with PAD (group A) and without PAD (group B) and similar indications for therapeutic ERCP were prospectively compared. The comparison included patient characteristics, findings of ERCP, and details of procedure and fluoroscopy time. The influence of papilla's location with respect to the diverticulum on procedure was also investigated. RESULTS: A total of 428 consecutive patients who had undergone therapeutic ERCP for similar indications were divided in two groups according to the presence (group A, 107 patients) or absence (group B, 321 patients) of PAD. The mean age and ASA score of the patients with PAD were significantly higher than those patients without PAD. The main indication was choledocholithiasis. Successful final CBD cannulation was achieved in 97.20% of the patients in group A vs 99.69% in group B (P=0.05). CBD diameter, number of stones and the largest stone size were significantly higher in group A than group B (P<0.001). Complete clearance of the CBD after the first attempt was achieved in 85.86% and 94.75% of the patients in groups A and B, respectively (P=0.03). In both groups, the time needed to complete the procedure and fluoroscopy time was significantly longer in patients with PAD (22.87 vs 18.99 minutes, P<0.001; 76.51 vs 47.42 seconds, P<0.001). There was no significant difference between the two groups in the complication rate. The type of papilla's location with respect to the diverticulum did not influence the total cannulation rate and post-procedure complications. CONCLUSION: The presence of a PAD does not affect the success rate and complications of therapeutic ERCP in expert hands; however, the fluoroscopy time is significantly longer in patients with PAD.

Innate immunity and nonalcoholic fatty liver disease.

Nonalcoholic fatty liver disease (NAFLD), recently renamed as metabolic (dysfunction)-associated fatty liver disease (MAFLD), is a complex, multifactorial disease that progresses via nonalcoholic steatohepatitis (NASH) towards severe liver complications. MAFLD/NAFLD affects up to a third of the global population. It is connected with metabolic syndrome parameters and has been increasing in parallel with the rates of metabolic syndrome parameters worldwide. This disease entity exhibits a strong immune-inflammatory dimension. In MAFLD/NAFLD/NASH, a vast network of innate immune cells is mobilized that can provoke liver damage, leading to advanced fibrosis, cirrhosis and its complications, including hepatocellular carcinoma. However, our understanding of the inflammatory signals that drive the onset and progression of MAFLD/NAFLD/NASH is fragmented. Thus, further investigation is required to better understand the role of specific innate immune cell subsets in the disease, and to aid the design of innovative therapeutic agents to target MAFLD/NAFLD/NASH. In this review, we discuss current concepts regarding the role of innate immune system involvement in MAFLD/NAFLD/NASH onset and progression, along with presenting potential stress signals affecting immune tolerance that may trigger aberrant immune responses. A comprehensive understanding of the innate immune mechanisms involved in MAFLD/NAFLD/NASH pathophysiology will help the discovery of early interventions to prevent the disease, and lead to potential innovative therapeutic strategies that may limit its worldwide burden.

Nonalcoholic fatty liver disease: multimodal treatment options for a pathogenetically multiple-hit disease.

Nonalcoholic fatty liver disease (NAFLD) has emerged as a significant public health problem. Besides the liver, NAFLD is also associated with increased cardiovascular and overall morbidity and mortality. NAFLD warrants intensive research, because no treatment has been established as yet. This may be partly attributed to the fact that the majority of the relative clinical trials have a monotherapeutic direction. However, the multifactorial pathogenesis of NAFLD may probably direct clinical trials to a combined therapeutic approach. The aim of this review is to provide a description of the multifactorial pathogenesis of NAFLD and type II diabetes mellitus-NAFLD interplay, and to summarize the therapeutic trials focusing on the combined NAFLD treatment, providing a link between the multiple-hit pathogenesis and the multimodal treatment of NAFLD patients. A diabetes-like therapeutic approach for NAFLD is finally proposed.

Comparison of three types of precut technique to achieve common bile duct cannulation: a retrospective analysis of 274 cases.

BACKGROUND: The aim of this retrospective study was to evaluate the success rate and complications of three precut techniques of sphincterotomy after failure of conventional techniques of cannulation of common bile duct (CBD). PATIENTS AND METHODS: Between January 2003 and October 2011, 2,903 consecutive ERCPs were performed in patients with naïve major papilla. In 283 patients in whom biliary cannulation was not achieved, precut technique was performed and these patients were included in the study. RESULTS: A total of 274 patients were included in the final analysis. Needle-knife papillotomy (NKP) was performed in 129 cases (47.1 %), suprapapillary fistulotomy (SPF) in 78 patients (28.5 %), and transpancreatic sphincterotomy (TPS) in 67 cases (24.5 %). No significant difference was observed in the initial and eventual success rate of biliary cannulation between the three groups. Overall, complications occurred in 54 patients (19.7 %), of which 33 (25.6 %) were with NKP, 6 (7.7 %) with SPF and 15 (22.4 %) with TPS, respectively, a difference statistically significant favoring the SPF group (p = 0.006). Post-procedure acute pancreatitis was developed in 27 cases (20.9 %) with NKP, compared to two cases (2.6 %) with SPF and 15 cases (22.4 %) with TPS, a difference statistically significant favoring the SPF group. No difference was observed between the groups with regard to the occurrence of post-procedure hemorrhage and perforation. CONCLUSIONS: The three types of precut sphincterotomy have no different overall CBD cannulation rates; SPF reduces post-ERCP pancreatitis risk.

Serum homocysteine levels in patients with nonalcoholic fatty liver disease.

Background and rational for the study. Nonalcoholic fatty liver disease (NAFLD) is regarded as the hepatic component of insulin resistance (IR) syndrome, but data on serum homocysteine (HCY) are limited. The aim of the study was the evaluation of serum HCY levels in patients with NAFLD. Material and methods. Thirty-one patients (54 ± 11 years, 8 males) with biopsy-proven NAFLD, 15 with simple nonalcoholic fatty liver (NAFL) and 16 with nonalcoholic steatohepatitis (NASH), and 22 healthy controls (52 ± 9 years, 5 males) matched for gender, age and body mass index (BMI), were recruited. Blood samples for HCY, folate, vitamin B12, insulin and standard biochemical tests were obtained after overnight fasting. Homeostatic model of assessment-insulin resistance (HOMA-IR) was calculated. Results. There was no difference in mean serum HCY levels between controls and NAFLD patients (12.6 ± 4.6 vs. 13.5 ± 2.6 mmol/L, respectively; p = 0.432). Serum folate and vitamin B12 were also similar between the study groups. Mean age, BMI, serum folate and vitamin B12 did not differ between NAFL and NASH patients. However, when compared with NAFL patients, NASH patients had lower mean serum HCY levels (12.3 ± 2.5 vs. 14.7 ± 2.1 mmol/L; p = 0.006). HCY was lower by increasing the grading of fibrosis (p = 0.005), portal inflammation (p = 0.029) and steatosis location (p = 0.021). In logistic regression analysis, HCY independently predicted NASH (p = 0.045) after adjustment for gender, age, BMI, AST, glucose and HOMA-IR. Conclusion. Our data suggest that serum HCY levels are lower in NASH compared with NAFL patients and can independently predict NASH. Serum HCY might represent another non-invasive marker for the assessment of NAFLD.

Histological presence of Helicobacter pylori bacteria in the trabeculum and iris of patients with primary open-angle glaucoma.

PURPOSE: To investigate the role of Helicobacter pylori in primary open-angle glaucoma (POAG) pathophysiology by detecting its presence in eye biopsies of POAG patients during trabeculectomy. PATIENTS AND METHODS: Fifty-one consecutive patients who underwent trabeculectomy for POAG not responsive to antiglaucoma therapy, and 35 consecutive anemic controls were examined for H. pylori presence mainly by gastric mucosa histology. In POAG patients, eye biopsies were also obtained and stained for H. pylori presence in situ. RESULTS: Forty-three of 51 (84.3%) POAG patients and 17 of 35 (48.6%) controls were tested H. pylori positive (p = 0.0004). In 5 H. pylori-positive POAG patients, H. pylori bacteria were identified in the trabeculum and iris specimens. CONCLUSION: For the first time, H. pylori bacteria have been detected histologically in eye biopsies of POAG patients.