Changes in the immune system – the key to diagnostics and therapy of patients with non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is the number one chronic liver disease worldwide and is estimated to affect nearly 40% of obese youth and up to 10% of the general pediatric population without any obvious signs or symptoms. Although the early stages of NAFLD are reversible with diet and lifestyle modifications, detecting such stages is hindered by a lack of non-invasive methods of risk assessment and diagnosis. This absence of non-invasive means of diagnosis is directly related to the scarcity of long-term prospective studies of pediatric NAFLD in children and adolescents. In the majority of pediatric NAFLD cases, the mechanisms driving the origin and rapid progression of NAFLD remain unknown. The progression from NAFLD to non-alcoholic steatohepatitis (NASH) in youth is associated with unique histological features and possible immune processes and metabolic pathways that may reflect different mechanisms compared with adults. Recent data suggest that circulating microRNAs (miRNAs) are important new biomarkers underlying pathways of liver injury. Several factors may contribute to pediatric NAFLD development, including high-sugar diets, in utero exposures via epigenetic alterations, changes in the neonatal microbiome, and altered immune system development and mitochondrial function. This review focuses on the unique aspects of pediatric NAFLD and how nutritional exposures impact the immune system, mitochondria, and liver/gastrointestinal metabolic health. These factors highlight the need for answers to how NAFLD develops in children and for early stage-specific interventions.

Download Full-text

Complement Component C3: A Novel Biomarker Participating in the Pathogenesis of Non-alcoholic Fatty Liver Disease

Frontiers in Medicine ◽

10.3389/fmed.2021.653293 ◽

2021 ◽

Vol 8 ◽

Author(s):

Juqiang Han ◽

Xiang Zhang

Keyword(s):

Immune System ◽

Liver Disease ◽

Fatty Liver ◽

Complement System ◽

Innate Immune System ◽

Fatty Liver Disease ◽

Complement Component ◽

Innate Immune ◽

Alcoholic Fatty Liver ◽

Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is currently the most common cause of chronic liver disorder worldwide. The pathological spectrum of NAFLD ranges from simple steatosis to non-alcoholic steatohepatitis (NASH) that induces progressive liver cirrhosis and eventually hepatocellular carcinoma (HCC). However, the molecular mechanisms driving the transformation of NASH are obscure. There is a compelling need for understanding the pathogenic mechanisms of NASH, and thereby providing new insight into mechanism-based therapy. Currently, several studies reported that complement system, an innate immune system, played an important role in the pathogenesis of NAFLD, which was also proved by our recent study. Complement component 3 (C3), a protein of the innate immune system, plays a hub role in the complement system. Herein, we present a review on the role and molecular mechanism of C3 in NASH as well as its implication in NASH diagnosis and treatment.

Download Full-text

Inflammation and Fibrogenesis in MAFLD: Role of the Hepatic Immune System

Frontiers in Medicine ◽

10.3389/fmed.2021.781567 ◽

2021 ◽

Vol 8 ◽

Author(s):

Pietro Torre ◽

Benedetta Maria Motta ◽

Roberta Sciorio ◽

Mario Masarone ◽

Marcello Persico

Keyword(s):

Immune System ◽

Liver Disease ◽

Fatty Liver ◽

Fatty Liver Disease ◽

Liver Diseases ◽

Metabolic Dysfunction ◽

Therapeutic Approaches ◽

Alcoholic Fatty Liver ◽

Alcoholic Fatty Liver Disease

Metabolic (dysfunction)-associated fatty liver disease (MAFLD) is the definition recently proposed to better circumscribe the spectrum of conditions long known as non-alcoholic fatty liver disease (NAFLD) that range from simple steatosis without inflammation to more advanced liver diseases. The progression of MAFLD, as well as other chronic liver diseases, toward cirrhosis, is driven by hepatic inflammation and fibrogenesis. The latter, result of a “chronic wound healing reaction,” is a dynamic process, and the understanding of its underlying pathophysiological events has increased in recent years. Fibrosis progresses in a microenvironment where it takes part an interplay between fibrogenic cells and many other elements, including some cells of the immune system with an underexplored or still unclear role in liver diseases. Some therapeutic approaches, also acting on the immune system, have been probed over time to evaluate their ability to improve inflammation and fibrosis in NAFLD, but to date no drug has been approved to treat this condition. In this review, we will focus on the contribution of the liver immune system in the progression of NAFLD, and on therapies under study that aim to counter the immune substrate of the disease.

Download Full-text

Vitamin D levels are not associated with non-alcoholic fatty liver disease severity in a Brazilian population

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000667 ◽

2020 ◽

pp. 1-8

Author(s):

Jeniffer Danielle M. Dutra ◽

Quelson Coelho Lisboa ◽

Silvia Marinho Ferolla ◽

Carolina Martinelli M. L. Carvalho ◽

Camila Costa M. Mendes ◽

...

Keyword(s):

Vitamin D ◽

Liver Disease ◽

Fatty Liver ◽

Disease Severity ◽

Fatty Liver Disease ◽

Hypovitaminosis D ◽

Alcoholic Fatty Liver ◽

Vitamin D Levels ◽

The Mean ◽

Alcoholic Fatty Liver Disease

Abstract. Some epidemiological evidence suggests an inverse correlation between non-alcoholic fatty liver disease (NAFLD) frequency and vitamin D levels. Likewise, a beneficial effect of vitamin D on diabetes mellitus (DM) and insulin resistance has been observed, but this is an unsolved issue. Thus, we aimed to investigate the prevalence of hypovitaminosis D in a NAFLD Brazilian population and its association with disease severity and presence of comorbidities. In a cross-sectional study, the clinical, biochemical and histological parameters of 139 NAFLD patients were evaluated according to two different cut-off points of serum 25-hydroxyvitamin D levels (20 ng/mL and 30 ng/mL). The mean age of the population was 56 ± 16 years, most patients were female (83%), 72% had hypertension, 88% dyslipidemia, 46% DM, 98% central obesity, and 82% metabolic syndrome. Serum vitamin D levels were < 30 ng/mL in 78% of the patients, and < 20 ng/mL in 35%. The mean vitamin D level was 24.3 ± 6.8 ng/mL. The comparison between the clinical, biochemical and histological characteristics of the patients according to the levels of vitamin D showed no significant difference. Most patients with NAFLD had hypovitaminosis D, but low vitamin D levels were not related to disease severity and the presence of comorbidities.

Download Full-text

Non-Alcoholic Fatty Liver Disease in Overweight Children and its Relationship with Retinol Serum Levels

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831.78.1.27 ◽

2008 ◽

Vol 78 (1) ◽

pp. 27-32 ◽

Cited By ~ 15

Author(s):

Suano de Souza ◽

Silverio Amancio ◽

Saccardo Sarni ◽

Sacchi Pitta ◽

Fernandes ◽

...

Keyword(s):

Insulin Resistance ◽

Liver Disease ◽

Fatty Liver ◽

Lipid Profile ◽

Fatty Liver Disease ◽

Thiobarbituric Acid ◽

Serum Levels ◽

Control Group ◽

Alcoholic Fatty Liver ◽

Alcoholic Fatty Liver Disease

Objectives: To evaluate the frequency of non-alcoholic fatty liver disease, the retinol serum levels, lipid profile, and insulin resistance in overweight/obese children. To relate these biochemical variables with the risk of this disease in the population studied. Methods: The study was cross-sectional and prospective, with 46 overweight/obese school children (28 female, 18 male; mean age 8.6 years). The control group consisted of 45 children, paired by age and gender. Hepatic steatosis, evaluated by ultrasound, was classified as normal, mild, moderate, or severe. Also evaluated were serum retinol levels; thiobarbituric acid reactive substances; lipid profile; and fasting glucose and serum insulin levels, used for the calculation of the Homeostasis Model Assessment. Results: Hepatic ultrasound alterations were found in 56.5% and 48,9% of the overweight/obese and control group children, respectively. Presence of obesity was associated with high levels of triglycerides (OR = 4.6; P = 0.002). In the studied children, the risk of steatosis was related to a trend to a higher percentage of retinol inadequacy (OR = 2.8; p = 0.051); there was no association with thiobarbituric acid reactive substances, lipid profile, or insulin resistance. Conclusions: The high frequency of non-alcoholic fatty liver disease in both groups, evaluated by hepatic ultrasound, in low-socioeconomic level children, independent of nutritional condition and without significant association with insulin resistance, emphasizes that especially in developing countries, other risk factors such as micronutrient deficiencies (e.g. vitamin A) are involved.

Download Full-text