Pathogenesis of Non-alcoholic Steatohepatitis and Liver Regeneration After Bariatric Surgery
Bariatric Surgery CandidateNonalcoholic Steatohepatitis1 moreObesity and obesity related health problems are globally recognized as one of the major threats to public health. Bariatric surgery is the most effective and durable therapy option for obesity and the improvement of obesity related co-morbidities. "Non alcoholic steatohepatitis" (NASH) is an important comorbidity of obesity and improves after surgical intervention. In this study investigators try to enlighten the weight independent mechanism for the effects of bariatric surgery. Patients who are assigned to a bariatric procedure will be observed for at least 24 month. A liver and adipose tissue samples are gained during the operation. Liver function and morphology are observed before and after operation with LiMAx, FibroScan and ultrasound. Systemic inflammation is measured in blood samples before and after surgical intervention. In order to check the microbiome stool samples are collected throughout the entire observation period.
Nonalcoholic Fatty Liver Disease in Morbidly Obese Patients
Nonalcoholic Fatty Liver Disease (NAFLD)Nonalcoholic fatty liver disease (NAFLD) is the most common cause of abnormal liver biochemistry tests in the world. The prevalence rate of NAFLD has been reported to be 30-40% in men and 15-20% in women, up to 70% of people with type 2 diabetes mellitus (Type 2 DM) and even surpassing 74% to 90% of morbidly obese patients with body mass index (BMI) higher than 35 kg/m^2. The primary aims of this prospective cohort study would evaluate the predictive factors of successful weight reduction, NAFLD and nonalcoholic steatohepatitis (NASH) improvement in a large cohort of morbidly obese patients undergoing bariatric surgery. Secondarily, the diagnostic accuracy of noninvasive serum markers, doppler ultrasonography and transient elastography would be validated. Thirdly, we would conduct gene expression analyses to elucidate biological pathways underlying NAFLD phenotypes in this unique cohort.
Measuring Fatty Liver With Ultrasound and MRS in Children With Overweight or Obesity
Non-Alcoholic Fatty Liver DiseaseObesity is associated with a variety of comorbidities, amongst which non-alcoholic fatty liver disease (NAFLD). A recent meta-analysis has shown that the prevalence of NAFLD in obese pediatric populations is around 35%, compared to approximately 8% in general pediatric populations, making it a very important health threat in these populations. The golden standard for diagnosis of NAFLD is liver biopsy. However, since liver biopsy is associated with a certain risk of morbidity and mortality, this method is inappropriate for screening large populations at-risk for developing NAFLD. Magnetic resonance spectroscopy has demonstrated excellent correlation with liver biopsy and the is the most accuratete non-invasive method to measure liver fat content in children. However, MRS is expensive and not available in all centres. A novel ultrasonographic measurement to quantitatively assess liver steatosis is the hepatorenal index (HRI). Previous studies have shown high sensitivity and specificity of the HRI, as compared to MRS and liver biopsy. However, this measurement has never been validated in children. In this study, the HRI will be compared to MRS in children with obesity, to validate the HRI and to determine cut-off points.
Non-invasive Diagnostic Model of Liver Fibrosis Associated With NAFLD and Prediction of Prognosis...
Non-alcoholic Fatty Liver DiseaseIn a retrospective study, 200 patients with non-alcoholic fatty liver disease, fatty liver hepatitis, and fatty liver fibrosis have been identified for pathological diagnosis of liver histology and exclusion of other liver diseases. Before the liver biopsy were performed, these patients should detect liver function, coagulation function, renal function, blood glucose, blood lipids, liver elasticity measurement and imaging indicators and results, and demographic data. To evaluate the diagnostic ability of the current non-invasive diagnostic model of NAFLD fibrosis and the adaptability of model indicators to the diagnosis of enrolled patients, and to correct the indicators, including discarding unsuitable indicators and incorporating new indicators, and adjusting the diagnostic score. Establish a non-invasive diagnostic model for liver fibrosis in Beijing based on NAFLD. In a prospective observational study, 100 patients without other liver diseases and ultrasound-tested fatty liver were enrolled, and histopathological diagnosis of liver were included in the study, and liver function, coagulation function, renal function, blood glucose, and non-invasive model analysis were detected. Blood lipids, liver elasticity measurements, and imaging indicators were examined and demographic data were collected. The non-invasive diagnostic model established by retrospective study was used to diagnose fibrosis and its staging, compared with histopathological diagnosis, and adjusted the index of non-invasive diagnostic model to further revise and improve the diagnostic efficacy of the diagnostic model. Long-term follow-up observations were performed in the prospective observation cohort. The liver function, coagulation function, renal function, blood glucose, blood lipids, liver elasticity and imaging examination were performed during the observation period, and the treatment events and the progress of the patients were recorded. To explore the correlation and predictive ability of noninvasive diagnostic models for long-term outcomes of disease. Finally, a model for predicting the outcome of progression of liver fibrosis in NAFLD was established.
Endoscopic Bariatric Therapy in NASH Cirrhosis
Non-alcoholic Steatohepatitis (NASH)Non-alcoholic steatohepatitis (NASH) is a growing public health problem that affects more than 5% of the population and can lead to cirrhosis and hepatocellular carcinoma. These patients are at greater risk of cardiovascular and hepatic death, and higher rates of neoplasms, both gastrointestinal and extra-intestinal. The standard treatment is weight loss with diet and physical exercise, which has shown a histological and analytical improvement in patients who achieve a 5-10% reduction in body weight. However, less than 25% of subjects achieve this goal. Restrictive surgical treatments and gastric bypass have achieved, in obese patients, an improvement in metabolic syndrome, insulin resistance and liver histology, but in patients with liver cirrhosis the morbidity-mortality of this surgery is high. Currently, endoscopic techniques are being developed, which are less invasive and have fewer complications, and which also achieve gastric restriction with similar characteristics to those obtained by the surgical method. Among them is the tubulization or vertical gastroplasty with the OverStitch system (Apollo Endosurgery, Austin, TX, USA). However, this method has not been evaluated in patients with obesity and/or metabolic syndrome and NASH cirrhosis. For this reason, the main objective of the investigators study is to evaluate the safety and efficacy of endoscopic gastroplasty in improving metabolic factors and liver histology in patients with obesity with or without metabolic syndrome and NASH-compensated cirrhosis.
Urinary Metabonomics of Two Major Patterns of NAFLD
Non-alcoholic Fatty Liver DiseaseNAFLD(non-alcoholic fatty liver disease, NAFLD) is a common liver disease with a high morbidity which seriously influence people's health. In clinical, there are two major Traditional chinese medicine(TCM) patterns which are the pattern of "liver depression and spleen deficiency" and pattern of "damp-heat in the interior", According to TCM patterns, the treatment is effective, but not used worldwide. While the development of metabonomics provides a tool to investigate the correlation of TCM patterns and metabonomics which will promote the further development of TCM. Currently researches on NAFLD patterns based on metabolomics were limited. Our study was undertaken to investigate the correlation of TCM patterns and metabonomics, to evaluate the application of urinary metabonomics in NAFLD: whether it can be used in TCM patterns auxiliary classification of NAFLD. In addition, the investigators also aim to discover novel biomarkers for the noninvasive early diagnosis of nonalcoholic fatty liver disease (NAFLD). In this study, urine samples from humans of three divided groups (healthy controls, the group of "liver depression and spleen deficiency" pattern and group of "damp-heat in the interior pattern) were collected, then 4℃, 15 min 3000 rpm centrifuged and - 80℃ cryopreserved. The metabolic profile changes were analyzed by Gas Chromatograph-Mass Spectrometer(GC/MS) with principal component analysis (PCA), partial least squares-discriminate analysis (PLS-DA) and orthogonal partial least squares-discriminate analysis (OPLS-DA). Furthermore, biochemical examination were also carried out to compare among these three groups. Base on literature survey, the investigators inferred that there should be metabolic differences between the two patterns of NAFLD. If the investigators hypothesis is correct, the investigators can find different metabolites which can be used discriminate between NAFLD and healthy population, different patterns through urinary metabonomics. The results will be attractive which mean a lot: it will prove the importance of the four diagnosis methods of TCM used in differential analysis by metabonomics; it will validate the classification of TCM syndromes is scientific; it will shed light in the study of TCM syndromes; it will find biology markers to help diagnosis, treatment and pattern discrimination.
The Effects of Bariatric Surgeries on Non-Alcoholic Fatty Liver Disease
ObesityMorbid1 moreNon-alcoholic fatty liver disease (NAFLD) is the most common form of chronic liver disease. In the absence of chronic alcohol abuse or other liver diseases, NAFLD incorporates a wide spectrum of liver pathologies and is defined by fatty infiltration of the liver (simple hepatosteatosis). It can progress to non-alcoholic steatohepatitis (NASH) and later fibrosis, cirrhosis, and eventually some patients may develop hepatocellular carcinoma with or without cirrhosis. The exact cause of NAFLD is yet to be cleared and it is, therefore, an active area for research. The diagnosis of NAFLD is achieved through histological examination of liver biopsies (invasive), non-invasive markers using serum biomarkers and imaging techniques are still under development. Pathological diagnosis can be then subcategorized based on several scoring systems. More widely used are the Brunt Score or NAS (NAFLD activity score) and the Kleiner's modified NAS. Obesity is highly associated with NAFLD, as the epidemic of obesity has made NAFLD more prevalent. In addition insulin resistance has been linked to NAFLD and this is explained by the increased influx of free fatty acids (FFAs) into the liver. FFA undergoes either β-oxidation or esterification with glycerol to form triglycerides (TGs), resulting in an additional source of fat in the liver. Due to the strong association of NAFLD with obesity, weight reduction procedures are used for the management of NAFLD. In fact, this has been shown to be effective by several studies. However, other studies have reported liver deterioration after bariatric intervention. This conflict is what makes the effects of bariatric procedures a challenging field for further studies. Consequently in this study we are aimed to examine histologic, metabolic and liver function changes induced by the different therapeutic bariatric procedures.
Meta-analyses of Fructose and Cardiometabolic Risk
DyslipidemiaDiabetes9 moreDiabetes and heart associations continue to discourage high intakes of dietary fructose, a constituent part of the sucrose molecule that is found in fruits and vegetables as a natural sugar and in some processed foods and beverages as an added sweetener. The concern relates to its ability to increase certain blood fats and cholesterol, which increase the risk of cardiovascular disease. The evidence for an adverse effect of fructose on these risk factors, however, is inconclusive. To improve the evidence on which nutrition recommendations for fructose are based, the investigators therefore propose to study the effect of fructose on blood fats, cholesterol, sugars, blood pressure, and body weight, by undertaking a systematic synthesis of the data taken from all available clinical studies in humans. This technique has the strength of allowing all of the available data to be pooled together and differences to be explored in groups of different study participants (healthy humans of different sex, weight, and age and in those with diseases which predispose to disturbances in metabolism, such as diabetes) with dietary fructose in different forms, doses, and with differing durations of exposure. The findings generated by this proposed knowledge synthesis will help improve the health of consumers through informing recommendations for the general public, as well as those at risk of diabetes and cardiovascular disease.
NASH and Type 2 Diabetes: Role of the Receptor Activator of Nuclear Factor-κB (RANK) and Its Ligand...
Diabetes type2NASH - Nonalcoholic Steatohepatitis1 moreNon-alcoholic fatty liver diseases (NAFLD) include several entities ranging from simple steatosis to hepatic fibrosis or cirrhosis. Steatosis, considered benign and the first stage of the disease, is characterized by the accumulation of triglycerides in the liver. It may in some cases progress to nonalcoholic steatohepatitis (NASH), which is characterized by the presence of a marked inflammation with or without fibrosis. NAFLD is the most common liver disease in the world and is particularly associated with type 2 diabetes (T2D) (80% in the diabetic population). While NASH is characterized by a higher prevalence of mortality from a cardiac and hepatic (cirrhosis and cancer) origin, therapeutic resources are almost non-existent. RANK (receptor activator of NF-kB) and its ligand RANKL (a member of the TNFalpha family) have emerged in recent years as new players in bone pathophysiology. By binding to its receptor, RANKL induces a number of signaling pathway and in particular the NF-kB pathway (Nuclear factor-kB), a major player in inflammation. Recent literature shows that the role of RANK / RANKL is not confined to the bone but may be involved in the genesis of inflammation in other tissues. It has been shown recently that a high circulating level of RANKL was a risk factor predictor of T2DM. Furthermore, the invalidation of RANK specifically in hepatocytes protects from insulin resistance and hepatic steatosis induced by a high fat diet in mice. The aim of our project is to provide a proof of concept that the RANKL / RANK system plays an important role in the pathogenesis of NAFLD and in the progression of this disease to NASH. The aim of our project is to provide a proof of concept that the RANKL / RANK system plays an important role in the pathogenesis of NAFLD and in the progression of this disease to NASH. The investigator propose to study the RANKL / RANK expression in serum and liver biopsies of type 2 diabetic patients at different stages of NAFLD.
MRI and Stable Isotope Tracer Studies for Detecting the Progression of Non-Alcoholic Steatohepatitis...
Non-Alcoholic Fatty Liver DiseaseOne-third of the world's population suffers from Non-Alcoholic Fatty Liver Disease (NAFLD), that is a disease with an accumulation of fat in the liver. Some patients with NAFLD will progress in their disease to develop inflammation, scarring of the liver tissue, and cirrhosis that can lead to liver failure. The mechanisms of the disease and its progression are still not fully understood. It is therefore critical to find early markers that can identify the patients that will progress so that they can be treated early. A compound called L-carnitine, synthesised in the body from two amino acids; lysine and methionine, is critical for fat metabolism. Some studies have shown that it is decreased in liver disease patients and that L-carnitine supplementation can protect the liver function. This study aims to increase the understanding of the mechanisms behind NAFLD disease progression through its different stages. This may help diagnostic methods to be developed to predict the patients at risk for developing severe liver disease. Furthermore, fat metabolism and L-carnitine levels will be established in the different disease stages to evaluate whether fat metabolism could be compromised. Magnetic Resonance Imaging (MRI) will be used for imaging of the whole liver and the heart to investigate metabolism and function non-invasively. Whole-body metabolism and how carbohydrates are taken up from diets are converted to fats in the body will be explored using stable isotope labelling. This study will recruit 30 participants with NAFLD; 10 each for low-risk NALFD, biopsy-proven NASH and compensated NASH cirrhosis. Participants will undergo MRI, followed by a stable isotope labelled study, where through blood- and breathe samples, metabolism will be investigated. An additional 10 healthy participants will be assessed using MR techniques to assess whether an injection of L-carnitine can lead to increase of L-carnitine in the liver such that it can be detected by MR. This is to validate a methodology prior to using it in NAFLD participants.