Early diet-induced non-alcoholic steatohepatitis in APOE2 knock-in mice and its prevention by fibrates

The ubiquitin-like modifier FAT10 is induced in MASLD and impairs the lipid-regulatory activity of PPARα

BACKGROUND AND AIMS

Peroxisome Proliferator-Activated Receptor α (PPARα) is a key regulator of hepatic lipid metabolism and therefore a promising therapeutic target against Metabolic-dysfunction Associated Steatotic Liver Diseases (MASLD). However, its expression and activity decrease during disease progression and several of its agonists did not achieve sufficient efficiency in clinical trials with, surprisingly, a lack of steatosis improvement. Here, we identified the Human leukocyte antigen-F Adjacent Transcript 10 (FAT10) as an inhibitor of PPARα lipid metabolic activity during MASLD progression.

APPROACH AND RESULTS

In vivo, the expression of FAT10 is upregulated in human and murine MASLD livers upon disease progression and correlates negatively with PPARα expression. The increase of FAT10 occurs in hepatocytes in which both proteins interact. FAT10 silencing in vitro in hepatocytes increases PPARα target gene expression, promotes fatty acid oxidation and decreases intra-cellular lipid droplet content. In line, FAT10 overexpression in hepatocytes in vivo inhibits the lipid regulatory activity of PPARα in response to fasting and agonist treatment in conditions of physiological and pathological hepatic lipid overload.

CONCLUSIONS

FAT10 is induced during MASLD development and interacts with PPARα resulting in a decreased lipid metabolic response of PPARα to fasting or agonist treatment. Inhibition of the FAT10-PPARα interaction may provide a means to design potential therapeutic strategies against MASLD.

Treating NASH by targeting peroxisome proliferator-activated receptors

The pathophysiology of non-alcoholic steatohepatitis (NASH) encompasses a complex set of intra- and extrahepatic driving mechanisms, involving numerous metabolic, inflammatory, vascular and fibrogenic pathways. The peroxisome proliferator-activated receptors (PPARs) α, β/δ and γ belong to the nuclear receptor family of ligand-activated transcription factors. Activated PPARs modulate target tissue transcriptomic profiles, enabling the body's adaptation to changing nutritional, metabolic and inflammatory environments. PPARs hence regulate several pathways involved in NASH pathogenesis. Whereas single PPAR agonists exert robust anti-NASH activity in several preclinical models, their clinical effects on histological endpoints of NASH resolution and fibrosis regression appear more modest. Simultaneous activation of several PPAR isotypes across different organs and within-organ cell types, resulting in pleiotropic actions, enhances the therapeutic potential of PPAR agonists as pharmacological agents for NASH and NASH-related hepatic and extrahepatic morbidity, with some compounds having already shown clinical efficacy on histological endpoints.

Current Therapeutical Approaches Targeting Lipid Metabolism in NAFLD

Nonalcoholic fatty liver disease (NAFLD, including nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH)) is a high-prevalence disorder, affecting about 1 billion people, which can evolve to more severe conditions like cirrhosis or hepatocellular carcinoma. NAFLD is often concomitant with conditions of the metabolic syndrome, such as central obesity and insulin-resistance, but a specific drug able to revert NAFL and prevent its evolution towards NASH is still lacking. With the liver being a key organ in metabolic processes, the potential therapeutic strategies are many, and range from directly targeting the lipid metabolism to the prevention of tissue inflammation. However, side effects have been reported for the drugs tested up to now. In this review, different approaches to the treatment of NAFLD are presented, including newer therapies and ongoing clinical trials. Particular focus is placed on the reverse cholesterol transport system and on the agonists for nuclear factors like PPAR and FXR, but also drugs initially developed for other conditions such as incretins and thyromimetics along with validated natural compounds that have anti-inflammatory potential. This work provides an overview of the different therapeutic strategies currently being tested for NAFLD, other than, or along with, the recommendation of weight loss.

PPARα activation partially drives NAFLD development in liver-specific Hnf4a-null mice

HNF4α regulates various genes to maintain liver function. There have been reports linking HNF4α expression to the development of non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis. In this study, liver-specific Hnf4a-deficient mice (Hnf4aΔHep mice) developed hepatosteatosis and liver fibrosis, and they were found to have difficulty utilizing glucose. In Hnf4aΔHep mice, the expression of fatty acid oxidation-related genes, which are PPARα target genes, was increased in contrast to the decreased expression of PPARα, suggesting that Hnf4aΔHep mice take up more lipids in the liver instead of glucose. Furthermore, Hnf4aΔHep/Ppara-/- mice, which are simultaneously deficient in HNF4α and PPARα, showed improved hepatosteatosis and fibrosis. Increased C18:1 and C18:1/C18:0 ratio was observed in the livers of Hnf4aΔHep mice, and the transactivation of PPARα target gene was induced by C18:1. When the C18:1/C18:0 ratio was close to that of Hnf4aΔHep mouse liver, a significant increase in transactivation was observed. In addition, the expression of Pgc1a, a coactivator of PPARs, was increased, suggesting that elevated C18:1 and Pgc1a expression could contribute to PPARα activation in Hnf4aΔHep mice. These insights may contribute to the development of new diagnostic and therapeutic approaches for NAFLD by focusing on the HNF4α and PPARα signaling cascade.

Investigating microRNAs to Explain the Link between Cholesterol Metabolism and NAFLD in Humans: A Systematic Review

Non-Alcoholic Fatty Liver Disease (NAFLD) is characterized by hepatic free cholesterol accumulation. In addition, microRNAs (miRNAs) might be involved in NAFLD development. Therefore, we systematically reviewed the literature to examine the link between miRNAs and cholesterol metabolism in NAFLD. Nineteen studies were retrieved by a systematic search in September 2022. From these papers, we evaluated associations between 13 miRNAs with NAFLD and cholesterol metabolism. Additionally, their diagnostic potential was examined. Four miRNAs (miR122, 34a, 132 and 21) were associated with cholesterol metabolism and markers for NAFLD. MiR122 was upregulated in serum of NAFLD patients, increased with disease severity and correlated with HDL-C, TAG, VLDL-C, AST, ALT, ALP, lobular inflammation, hepatocellular ballooning and NAFLD score. Serum and hepatic levels also correlated. Serum and hepatic miR34a levels were increased in NAFLD, and correlated with VLDL-C and TAG. Serum miR379 was also higher in NAFLD, especially in early stages, while miR21 gave ambiguous results. The diagnostic properties of these miRNAs were comparable to those of existing biomarkers. However, serum miR122 levels appeared to be elevated before increases in ALT and AST were evident. In conclusion, miR122, miR34a, miR21 and miR132 may play a role in the development of NAFLD via effects on cholesterol metabolism. Furthermore, it needs to be explored if miRNAs 122, 34a and 379 could be used as part of a panel in addition to established biomarkers in early detection of NAFLD.

Molecular mechanisms of metabolic associated fatty liver disease (MAFLD): functional analysis of lipid metabolism pathways

The metabolic-associated fatty liver disease (MAFLD) is a condition of fat accumulation in the liver in combination with metabolic dysfunction in the form of overweight or obesity and insulin resistance. It is also associated with an increased cardiovascular disease risk, including hypertension and atherosclerosis. Hepatic lipid metabolism is regulated by a combination of the uptake and export of fatty acids, de novo lipogenesis, and fat utilization by β-oxidation. When the balance between these pathways is altered, hepatic lipid accumulation commences, and long-term activation of inflammatory and fibrotic pathways can progress to worsen the liver disease. This review discusses the details of the molecular mechanisms regulating hepatic lipids and the emerging therapies targeting these pathways as potential future treatments for MAFLD.

Peroxisome Proliferator-Activated Receptors and the Hallmarks of Cancer

Peroxisome proliferator-activated receptors (PPARs) function as nuclear transcription factors upon the binding of physiological or pharmacological ligands and heterodimerization with retinoic X receptors. Physiological ligands include fatty acids and fatty-acid-derived compounds with low specificity for the different PPAR subtypes (alpha, beta/delta, and gamma). For each of the PPAR subtypes, specific pharmacological agonists and antagonists, as well as pan-agonists, are available. In agreement with their natural ligands, PPARs are mainly focused on as targets for the treatment of metabolic syndrome and its associated complications. Nevertheless, many publications are available that implicate PPARs in malignancies. In several instances, they are controversial for very similar models. Thus, to better predict the potential use of PPAR modulators for personalized medicine in therapies against malignancies, it seems necessary and timely to review the three PPARs in relation to the didactic concept of cancer hallmark capabilities. We previously described the functions of PPAR beta/delta with respect to the cancer hallmarks and reviewed the implications of all PPARs in angiogenesis. Thus, the current review updates our knowledge on PPAR beta and the hallmarks of cancer and extends the concept to PPAR alpha and PPAR gamma.

Liver Protective Effect of Fenofibrate in NASH/NAFLD Animal Models

Nonalcoholic fatty liver disease (NAFLD) is initiated by excessive fat buildup in the liver, affecting around 35% of the world population. Various circumstances contribute to the initiation and progression of NAFLD, and it encompasses a wide range of disorders, from simple steatosis to nonalcoholic steatohepatitis (NASH), cirrhosis, and liver cancer. Although several treatments have been proposed, there is no definitive cure for NAFLD. In recent decades, several medications related to other metabolic disorders have been evaluated in preclinical studies and in clinical trials due to the correlation of NAFLD with other metabolic diseases. Fenofibrate is a fibrate drug approved for dyslipidemia that could be used for modulation of hepatic fat accumulation, targeting peroxisome proliferator-activator receptors, and de novo lipogenesis. This drug offers potential therapeutic efficacy for NAFLD due to its capacity to decrease the accumulation of hepatic lipids, as well as its antioxidant, anti-inflammatory, and antifibrotic properties. To better elucidate the pathophysiological processes underlying NAFLD, as well as to test therapeutic agents/interventions, experimental animal models have been extensively used. In this article, we first reviewed experimental animal models that have been used to evaluate the protective effects of fenofibrate on NAFLD/NASH. Next, we investigated the impact of fenofibrate on the hepatic microcirculation in NAFLD and then summarized the beneficial effects of fenofibrate, as compared to other drugs, for the treatment of NAFLD. Lastly, we discuss possible adverse side effects of fenofibrate on the liver.

Impact of fenofibrate on NAFLD/NASH: A genetic perspective

Nonalcoholic fatty liver disease (NAFLD), caused by an accumulation of fat deposits in hepatocytes, prevalently affects at least one-third of the world's population. The progression of this disorder can potentially include a spectrum of consecutive stages, specifically: steatosis, steatohepatitis and cirrhosis. Fenofibrate exhibits potential therapeutic efficacy for NAFLD owing to several properties, which include antioxidant, apoptotic, anti-inflammatory and antifibrotic activity. In the present review, we discuss the direct or indirect impact of fenofibrate on genes involved at various stages in the progression of NAFLD. Moreover, we have reviewed studies that compare fenofibrate with other drugs in treating NAFLD, as well as recent clinical trials, in an attempt to identify reliable scientific and clinical evidence concerning the therapeutic effects and benefits of fenofibrate on NAFLD. Teaser.

Investigation of the Effect of Curcumin on Protein Targets in NAFLD Using Bioinformatic Analysis

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a prevalent metabolic disorder. Defects in function/expression of genes/proteins are critical in initiation/progression of NAFLD. Natural products may modulate these genes/proteins. Curcumin improves steatosis, inflammation, and fibrosis progression. Here, bioinformatic tools, gene−drug and gene-disease databases were utilized to explore targets, interactions, and pathways through which curcumin could impact NAFLD. METHODS: Significant curcumin−protein interaction was identified (high-confidence:0.7) in the STITCH database. Identified proteins were investigated to determine association with NAFLD. gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were analyzed for significantly involved targets (p < 0.01). Specificity of obtained targets with NAFLD was estimated and investigated in Tissue/Cells−gene associations (PanglaoDB Augmented 2021, Mouse Gene Atlas) and Disease−gene association-based EnrichR algorithms (Jensen DISEASES, DisGeNET). RESULTS: Two collections were constructed: 227 protein−curcumin interactions and 95 NAFLD-associated genes. By Venn diagram, 14 significant targets were identified, and their biological pathways evaluated. Based on gene ontology, most targets involved stress and lipid metabolism. KEGG revealed chemical carcinogenesis, the AGE-RAGE signaling pathway in diabetic complications and NAFLD as the most common significant pathways. Specificity to diseases database (EnrichR algorithm) revealed specificity for steatosis/steatohepatitis. CONCLUSION: Curcumin may improve, or inhibit, progression of NAFLD through activation/inhibition of NAFLD-related genes.

Cell-Type Resolved Insights into the Cis-Regulatory Genome of NAFLD

The prevalence of non-alcoholic fatty liver disease (NAFLD) is increasing rapidly, and unmet treatment can result in the development of hepatitis, fibrosis, and liver failure. There are difficulties involved in diagnosing NAFLD early and for this reason there are challenges involved in its treatment. Furthermore, no drugs are currently approved to alleviate complications, a fact which highlights the need for further insight into disease mechanisms. NAFLD pathogenesis is associated with complex cellular changes, including hepatocyte steatosis, immune cell infiltration, endothelial dysfunction, hepatic stellate cell activation, and epithelial ductular reaction. Many of these cellular changes are controlled by dramatic changes in gene expression orchestrated by the cis-regulatory genome and associated transcription factors. Thus, to understand disease mechanisms, we need extensive insights into the gene regulatory mechanisms associated with tissue remodeling. Mapping cis-regulatory regions genome-wide is a step towards this objective and several current and emerging technologies allow detection of accessible chromatin and specific histone modifications in enriched cell populations of the liver, as well as in single cells. Here, we discuss recent insights into the cis-regulatory genome in NAFLD both at the organ-level and in specific cell populations of the liver. Moreover, we highlight emerging technologies that enable single-cell resolved analysis of the cis-regulatory genome of the liver.

Is there a role of lipid-lowering therapies in the management of fatty liver disease?

Atherogenic dyslipidemia is characterized by increased triglyceride-rich lipoproteins and low high-density lipoprotein cholesterol concentrations. It is highly prevalent in non-alcoholic fatty liver disease (NAFLD) and contributes to the increased cardiovascular risk associated with this condition. Alongside insulin resistance it plays an important pathogenetic role in NAFLD/non-alcoholic steatohepatitis (NASH) development and progression. It has been shown that cholesterol-lowering reduces cardiovascular risk more in NAFLD vs non-NAFLD high-risk individuals. This evidence highlights the importance of effective lipid modulation in NAFLD. In this narrative review the effects of the most commonly used lipid-lowering therapies on liver outcomes alongside their therapeutic implications in NAFLD/NASH are critically discussed. Preclinical and clinical evidence suggests that statins reduce hepatic steatosis, inflammation and fibrosis in patients with NAFLD/NASH. Most data are derived from observational and small prospective clinical studies using changes in liver enzyme activities, steatosis/fibrosis scores, and imaging evidence of steatosis as surrogates. Also, relevant histologic benefits were noted in small biopsy studies. Atorvastatin and rosuvastatin showed greater benefits, whereas data for other statins are scarce and sometimes conflicting. Similar studies to those of statins showed efficacy of ezetimibe against hepatic steatosis. However, no significant anti-inflammatory and anti-fibrotic actions of ezetimibe have been shown. Preclinical studies showed that fibrates through peroxisome proliferator-activated receptor (PPAR)α activation may have a role in NAFLD prevention and management. Nevertheless, no relevant benefits have been noted in human studies. Species-related differences in PPARα expression and its activation responsiveness may help explain this discrepancy. Omega-3 fatty acids reduced hepatic steatosis in numerous heterogeneous studies, but their benefits on hepatic inflammation and fibrosis have not been established. Promising preliminary data for the highly purified eicosapentaenoic acid require further confirmation. Observational studies suggest that proprotein convertase subtilisin/kexin9 inhibitors may also have a role in the management of NAFLD, though this needs to be established by future prospective studies.

Lipid-Lowering Responses to Dyslipidemia Determine the Efficacy on Liver Enzymes in Metabolic Dysfunction-Associated Fatty Liver Disease with Hepatic Injuries: A Prospective Cohort Study

PURPOSE

Effective treatment of dyslipidemia with lipid-lowering agents is pivotal in the management of metabolic-associated fatty liver disease (MAFLD) for preventing cardiovascular complications. We explored the associations between improvements in liver injuries indicated by changes in transaminases and a reduction in lipid levels in MAFLD patients with dyslipidemia and elevated transaminases during lipid-lowering therapies.

METHODS

This prospective, cohort study enrolled consecutive MAFLD patients with hyperlipidemia and elevated transaminases. Patients were divided into a group receiving lipid-lowering agents and an age-, sex- and baseline lipid level-matched control group without receiving lipid-lowering agents. Clinical visits were performed at the 1st month and then every 3 months for 1 year.

RESULTS

This study included 541 MAFLD patients (lipid-lowering group: 325 patients; control group: 216 patients). Compared with controls, there was a substantially greater reduction in alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma glutamyl transpeptidase (GGT), triglyceride (TG), total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-c) in the lipid-lowering group after 12 months (all P < 0.05). The decrease in ALT was positively correlated with the decrease in TC (r = 0.332), TG (r = 0.180), LDL-c (r = 0.253) and apolipoprotein E (ApoE) (r = 0.119), while the decrease in AST was positively correlated with the decrease in TC (r = 0.228) and LDL-c (r = 0.192) (all P<0.05). The greater range of reduction in blood lipids (TC/TG/LDL-c), the higher the transaminase and GGT normalization rate (all P<0.05). Multivariate analysis confirmed that a TG decrease of over 50% remained an independent predictor of transaminase and GGT normalization (OR 2.07, 95% CI 1.12-3.84, P=0.020).

CONCLUSION

Lipid-lowering to target levels might be beneficial to liver injury improvements in MAFLD patients with dyslipidemia when receiving lipid-lowering agents.

IL-19 Contributes to the Development of Nonalcoholic Steatohepatitis by Altering Lipid Metabolism

Interleukin (IL)-19, a member of the IL-10 family, is an anti-inflammatory cytokine produced primarily by macrophages. Nonalcoholic steatohepatitis (NASH) is a disease that has progressed from nonalcoholic fatty liver disease (NAFLD) and is characterized by inflammation and fibrosis. We evaluated the functions of IL-19 in a NAFLD/NASH mouse model using a 60% high fat diet with 0.1% methionine, without choline, and with 2% cholesterol (CDAHFD). Wild-type (WT) and IL-19 gene-deficient (KO) mice were fed a CDAHFD or standard diet for 9 weeks. Liver injury, inflammation, and fibrosis induced by CDAHFD were significantly worse in IL-19 KO mice than in WT mice. IL-6, TNF-α, and TGF-β were significantly higher in IL-19 KO mice than in WT mice. As a mechanism using an in vitro experiment, palmitate-induced triglyceride and cholesterol contents were decreased by the addition of IL-19 in HepG2 cells. Furthermore, addition of IL-19 decreased the expression of fatty acid synthesis-related enzymes and increased ATP content in HepG2 cells. The action of IL-19 in vitro suppressed lipid metabolism. In conclusion, IL-19 may play an important role in the development of steatosis and fibrosis by directly regulating liver metabolism and may be a potential target for the treatment of liver diseases.

The transcription factors CREBH, PPARa, and FOXO1 as critical hepatic mediators of diet-induced metabolic dysregulation

The liver is a critical mediator of lipid and/or glucose homeostasis and is a primary organ involved in dynamic changes during feeding and fasting. Additionally, hepatic-centric pathways are prone to dysregulation during pathophysiological states including metabolic syndrome (MetS) and non-alcoholic fatty liver disease. Omics platforms and GWAS have elucidated genes related to increased risk of developing MetS and related disorders, but mutations in these metabolism-related genes are rare and cannot fully explain the increasing prevalence of MetS-related pathologies worldwide. Complex interactions between diet, lifestyle, environmental factors, and genetic predisposition jointly determine inter-individual variability of disease risk. Given the complexity of these interactions, researchers have focused on master regulators of metabolic responses incorporating and mediating the impact of multiple environmental cues. Transcription factors are DNA binding, terminal executors of signaling pathways that modulate the cellular responses to complex metabolic stimuli and are related to the control of hepatic lipid and glucose homeostasis. Among numerous hepatic transcription factors involved in regulating metabolism, three emerge as key players in transducing nutrient sensing, which are dysregulated in MetS-related perturbations in both clinical and preclinical studies: cAMP Responsive Element Binding Protein 3 Like 3 (CREB3L3), Peroxisome Proliferator Activated Receptor Alpha (PPAR), and Forkhead Box O1 (FOXO1). Additionally, these three transcription factors appear to be amenable to dietary and/or nutrient-based therapies, being potential targets of nutritional therapy. In this review we aim to describe the activation, regulation, and impact of these transcription factors in the context of metabolic homeostasis. We also summarize their perspectives in MetS and nutritional therapies.

PPARs as Metabolic Sensors and Therapeutic Targets in Liver Diseases

Carbohydrates and lipids are two components of the diet that provide the necessary energy to carry out various physiological processes to help maintain homeostasis in the body. However, when the metabolism of both biomolecules is altered, development of various liver diseases takes place; such as metabolic-associated fatty liver diseases (MAFLD), hepatitis B and C virus infections, alcoholic liver disease (ALD), and in more severe cases, hepatocelular carcinoma (HCC). On the other hand, PPARs are a family of ligand-dependent transcription factors with an important role in the regulation of metabolic processes to hepatic level as well as in other organs. After interaction with specific ligands, PPARs are translocated to the nucleus, undergoing structural changes to regulate gene transcription involved in lipid metabolism, adipogenesis, inflammation and metabolic homeostasis. This review aims to provide updated data about PPARs’ critical role in liver metabolic regulation, and their involvement triggering the genesis of several liver diseases. Information is provided about their molecular characteristics, cell signal pathways, and the main pharmacological therapies that modulate their function, currently engaged in the clinic scenario, or in pharmacological development.

Administration of isoliquiritigenin prevents nonalcoholic fatty liver disease through a novel IQGAP2-CREB-SIRT1 axis

Isoliquiritigenin (ISO) is a flavonoid extracted from the root of licorice, which serves various biological and pharmacological functions including antiinflammatory, antioxidation, liver protection, and heart protection. However, the mechanism of its action remains elusive and the direct target proteins of ISO have not been identified so far. Through cell-based screening, we identified ISO as a potent lipid-lowering compound. ISO treatment successfully ameliorated fatty acid-induced cellular lipid accumulation and improved nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) by increasing PPARα-dependent lipid oxidation and decreasing SREBPs-dependent lipid synthesis. Both these signaling required the activation of SIRT1. Knockdown of SIRT1 resulted in the reversal of ISO beneficiary effects suggesting that the lipid-lowering activity of ISO was regulated by SIRT1 expression. To identify the direct target of ISO, limited proteolysis combined with mass spectrometry (LiP-SMap) strategy was applied and IQGAP2 was identified as the direct target for ISO in regulating lipid homeostasis. In the presence of ISO, both mRNA and protein levels of SIRT1 were increased; however, this effect was abolished by blocking IQGAP2 expression using siRNA. To explore how IQGAP2 regulated the expression level of SIRT1, proteome profiler human phospho-kinase array kit was used to reveal possible phosphorylated kinases and signaling nodes that ISO affected. We found that through phosphorylation of CREB, ISO transduced signals from IQGAP2 to upregulate SIRT1 expression. Thus, we not only demonstrated the molecular basis of ISO in regulating lipid metabolism but also exhibited for the first time a novel IQGAP2-CREB-SIRT1 axis in treating NAFLD/NASH.

Transcriptional Regulation of Metabolic Pathways via Lipid-Sensing Nuclear Receptors PPARs, FXR, and LXR in NASH

Nonalcoholic fatty liver disease comprises a wide spectrum of liver injuries from simple steatosis to steatohepatitis and cirrhosis. Nonalcoholic steatohepatitis (NASH) is defined when liver steatosis is associated with inflammation, hepatocyte damage, and fibrosis. A genetic predisposition and environmental insults (ie, dietary habits, obesity) are putatively responsible for NASH progression. Here, we present the impact of the lipid-sensing nuclear receptors in the pathogenesis and treatment of NASH. In detail, we discuss the pros and cons of the putative transcriptional action of the fatty acid sensors (peroxisome proliferator-activated receptors), the bile acid sensor (farnesoid X receptor), and the oxysterol sensor (liver X receptors) in the pathogenesis and bona fide treatment of NASH.

Crosstalk between PPARs and gut microbiota in NAFLD

Nonalcoholic fatty liver disease (NAFLD) has become the most common liver disorder in both China and worldwide. It ranges from simple steatosis and progresses over time to nonalcoholic steatohepatitis (NASH), advanced liver fibrosis, cirrhosis, or hepatocellular carcinoma(HCC). Furthermore, NAFLD and its complications impose a huge health burden to society. The microbiota is widely connected and plays an active role in human physiology and pathology, and it is a hidden 'organ' in determining the state of the host, in terms of homeostasis, or disease. Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear receptorsuperfamily and can regulate multiple pathways involved in metabolism, and serve as effective targets forthe treatment of many types of metabolic syndromes, including NAFLD. The purpose of this review is to integrate related articles on gut microbiota, PPARs and NAFLD, and present a balanced overview on how the microbiota can possibly influence the development of NAFLD through PPARs.

The role of peroxisome proliferator-activated receptors (PPAR) in immune responses

Peroxisome proliferator-activated receptors (PPARs) are fatty acid-activated transcription factors of nuclear hormone receptor superfamily that regulate energy metabolism. Currently, three PPAR subtypes have been identified: PPARα, PPARγ, and PPARβ/δ. PPARα and PPARδ are highly expressed in oxidative tissues and regulate genes involved in substrate delivery and oxidative phosphorylation (OXPHOS) and regulation of energy homeostasis. In contrast, PPARγ is more important in lipogenesis and lipid synthesis, with highest expression levels in white adipose tissue (WAT). In addition to tissues regulating whole body energy homeostasis, PPARs are expressed in immune cells and have an emerging critical role in immune cell differentiation and fate commitment. In this review, we discuss the actions of PPARs in the function of the innate and the adaptive immune system and their implications in immune-mediated inflammatory conditions.

Non-Alcoholic Steatohepatitis: A Review of Its Mechanism, Models and Medical Treatments

Non-alcoholic steatohepatitis (NASH) develops from non-alcoholic fatty liver disease (NAFLD). Currently, around 25% of the population is estimated to have NAFLD, and 25% of NAFLD patients are estimated to have NASH. NASH is typically characterized by liver steatosis inflammation, and fibrosis driven by metabolic disruptions such as obesity, diabetes, and dyslipidemia. NASH patients with significant fibrosis have increased risk of developing cirrhosis and liver failure. Currently, NASH is the second leading cause for liver transplant in the United States. More importantly, the risk of developing hepatocellular carcinoma from NASH has also been highlighted in recent studies. Patients may have NAFLD for years before progressing into NASH. Although the pathogenesis of NASH is not completely understood, the current “multiple-hits” hypothesis suggests that in addition to fat accumulation, elevated oxidative and ER stress may also drive liver inflammation and fibrosis. The development of clinically relevant animal models and pharmacological treatments for NASH have been hampered by the limited understanding of the disease mechanism and a lack of sensitive, non-invasive diagnostic tools. Currently, most pre-clinical animal models are divided into three main groups which includes: genetic models, diet-induced, and toxin + diet-induced animal models. Although dietary models mimic the natural course of NASH in humans, the models often only induce mild liver injury. Many genetic and toxin + diet-induced models rapidly induce the development of metabolic disruption and serious liver injury, but not without their own shortcomings. This review provides an overview of the “multiple-hits” hypothesis and an evaluation of the currently existing animal models of NASH. This review also provides an update on the available interventions for managing NASH as well as pharmacological agents that are currently undergoing clinical trials for the treatment of NASH.

Roles of Hepatic Innate and Innate-Like Lymphocytes in Nonalcoholic Steatohepatitis

Nonalcoholic steatohepatitis (NASH), a progressive form of nonalcoholic fatty liver disease (NAFLD), is accompanied by steatosis, hepatocyte injury and liver inflammation, which has been a health problem in the world as one of the major high risk factors of cirrhosis and hepatocellular carcinoma (HCC). Complex immune responses involving T cells, B cells, Kupffer cells, monocytes, neutrophils, DCs and other innate lymphocytes account for the pathogenesis of NASH; however, the underlying mechanisms have not been clearly elucidated in detail. In the liver, innate and innate-like lymphocytes account for more than two-thirds of total lymphocytes and play an important role in maintaining the immune homeostasis. Therefore, their roles in the progression of NASH deserves investigation. In this review, we summarized murine NASH models for immunological studies, including the diet-induced NASH, chemical-induced NASH and genetic-induced NASH. The role of innate and innate-like lymphocytes including NK cells, ILCs, NKT, γδT and MAIT cells in the progression of NASH were elucidated. Further, the metabolic regulation of the innate immune response was addressed in consideration to explain the molecular mechanisms. Based on the findings of the reviewed studies, strategies of immune intervention are proposed to control the progression of NASH.

Transcriptional Regulation in Non-Alcoholic Fatty Liver Disease

Obesity is the primary risk factor for the pathogenesis of non-alcoholic fatty liver disease (NAFLD), the worldwide prevalence of which continues to increase dramatically. The liver plays a pivotal role in the maintenance of whole-body lipid and glucose homeostasis. This is mainly mediated by the transcriptional activation of hepatic pathways that promote glucose and lipid production or utilization in response to the nutritional state of the body. However, in the setting of chronic excessive nutrition, the dysregulation of hepatic transcriptional machinery promotes lipid accumulation, inflammation, metabolic stress, and fibrosis, which culminate in NAFLD. In this review, we provide our current understanding of the transcription factors that have been linked to the pathogenesis and progression of NAFLD. Using publicly available transcriptomic data, we outline the altered activity of transcription factors among humans with NAFLD. By expanding this analysis to common experimental mouse models of NAFLD, we outline the relevance of mouse models to the human pathophysiology at the transcriptional level.

The polarity protein Scrib limits atherosclerosis development in mice

AIMS

The protein Scrib (Scribble 1) is known to control apico-basal polarity in epithelial cells. The role of polarity proteins in the vascular system remains poorly characterized; however, we previously reported that Scrib maintains the endothelial phenotype and directed migration. On this basis, we hypothesized that Scrib has anti-atherosclerotic functions.

METHODS AND RESULTS

Tamoxifen-induced Scrib-knockout mice were crossed with ApoE-/- knockout mice and spontaneous atherosclerosis under high-fat diet (HFD), as well as accelerated atherosclerosis in response to partial carotid artery ligation and HFD, was induced. Deletion of Scrib resulted in increased atherosclerosis development in both models. Mechanistically, flow- as well as acetylcholine-induced endothelium-dependent relaxation and AKT phosphorylation was reduced by deletion of Scrib, whereas vascular permeability and leucocyte extravasation were increased after Scrib knockout. Scrib immune pull down in primary carotid endothelial cells and mass spectrometry identified Arhgef7 (Rho Guanine Nucleotide Exchange Factor 7, βPix) as interaction partner. Scrib or Arhgef7 down-regulation by siRNA reduced the endothelial barrier function in human umbilical vein endothelial cells. Gene expression analysis from murine samples and from human biobank material of carotid endarterectomies indicated that loss of Scrib resulted in endothelial dedifferentiation with a decreased expression of endothelial signature genes.

CONCLUSIONS

By maintaining a quiescent endothelial phenotype, the polarity protein Scrib elicits anti-atherosclerotic functions.

Hepatoprotective effects of ZLY16, a dual peroxisome proliferator-activated receptor α/δ agonist, in rodent model of nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD), a chronic progressive liver disease, covers a series of liver damage encompassing steatosis, nonalcoholic steatohepatitis (NASH), fibrosis and cirrhosis. However, there are no approved therapies for NAFLD. Herein, we characterize the pharmacological profile of ZLY16 ((E)-2-(4-(3-(2,3-dihydrobenzo[b]thiophen -5-yl)-3-oxoprop-1-en-1-yl)-2,6-dimethylphenoxy)-2-methylpropanoic acid), a novel highly potent PPARα/δ agonist with relative higher potency on PPARγ. The chronic effects of ZLY16 on NASH development were evaluated in MCD-induced db/db mice. ZLY16 revealed decreased liver injury biomarkers, hepatic steatosis, inflammation, ballooning, and oxidative stress. Further mechanism researches suggested that ZLY16 inhibited liver inflammation and fibrosis by regulating gene expression including COLIA1, TIMP, TGFβ, TNFα, and IL6. Moreover, ZLY16 offers more favorable effects in decreasing liver TC and TG accumulation, blocking liver fibrosis and inflammation than GFT505, the most advanced candidate of PPARα/δ agonist for the treatment of NASH. These results indicate that ZLY16 is a highly potent PPARα/δ agonist that provides great protection against NASH development, and may be useful for the treatment of NAFLD/NASH.

Emerging targets and potential therapeutic agents in non-alcoholic fatty liver disease treatment

Nonalcoholic Fatty Liver Disease (NAFLD) is the most common chronic liver disease in the world, which is characterized by liver fat accumulation unrelated to excessive drinking. Indeed, it attracts growing attention and becomes a global health problem. Due to the complexity of the NAFLD pathogenic mechanism, no related drugs were approved by Food and Drug Administration (FDA) till now. However, it is encouraging that a series of candidate drugs have entered the clinical trial stage with expectation to treat NAFLD. In this review, we summarized the main pathways and pathogenic mechanisms of NAFLD, as well as introduced the main potential therapeutic targets and the corresponding compounds involved in metabolism, inflammation and fibrosis. Furthermore, we also discuss the progress of these compounds, such as drug design and optimization, the choice of pharmacological properties and druglikeness, and the analysis of structure-activity relationship. This review offers a medium on future drug design and development, to be beneficial to relevant studies.

Pemafibrate, a New Selective PPARα Modulator: Drug Concept and Its Clinical Applications for Dyslipidemia and Metabolic Diseases

PURPOSE OF REVIEW

Reduction of serum low-density lipoprotein cholesterol (LDL-C) levels by statins, ezetimibe and proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors has been shown to significantly reduce cardiovascular events risk. However, fasting and postprandial hypertriglyceridemia as well as reduced high-density lipoprotein cholesterol (HDL-C) remain as residual risk factors of atherosclerotic cardiovascular diseases (ASCVD). To treat patients with hypertriglyceridemia and/or low HDL-C, drugs such as fibrates, nicotinic acids, and n-3 polyunsaturated fatty acids have been used. However, fibrates were demonstrated to cause side effects such as liver dysfunction and increase in creatinine levels, and thus large-scale clinical trials of fibrates have shown negative results for prevention of ASCVD. The failure could be attributed to their low selectivity and potency for binding to peroxisome proliferator-activated receptor (PPAR) α. To resolve these issues, the concept of selective PPARα modulator (SPPARMα) with a superior balance of efficacy and safety has been proposed and pemafibrate (K-877) has been developed.

RECENT FINDINGS

Pemafibrate, one of SPPARMsα, was synthesized by Kowa Company, Ltd. for better efficiency and safety. Clinical trials in Japan have established the superiority of pemafibrate on effects on serum triglycerides (TG) reduction and HDL-C elevation as well safety. Although available fibrates showed worsening of liver and kidney function test values, pemafibrate indicated improved liver function test values and was less likely to increase serum creatinine or decrease estimated glomerular filtration rate (eGFR). Very few drug-drug interactions were observed even when used concomitantly with statins. Furthermore, pemafibrate is metabolized in the liver and excreted into the bile, while many of available fibrates are mainly excreted from the kidney. Therefore, pemafibrate can be used safely even in patients with impaired renal function since there is no significant increase in its blood concentration. A large-scale trial of pemafibrate, PROMINENT, for dyslipidemic patients with type 2 diabetes is ongoing. Pemafibrate is one of novel SPPARMsα and has superior benefit-risk balance compared to conventional fibrates and can be applicable for patients for whom the usage of existing fibrates is difficult such as those who are taking statins or patients with renal dysfunction. In the current review, all the recent data on pemafibrate will be summarized.

Is there a link between progranulin, obesity, and parameters of the metabolic syndrome in children? Findings from a longitudinal intervention study

BACKGROUND

The inflammatory cytokine progranulin has been proposed to play a role in obesity and its associated comorbidities such as insulin resistance.

OBJECTIVE

In a longitudinal study, we analyzed the links between progranulin, parameters of fat mass, insulin resistance, and metabolic syndrome (MetS) in obese children.

METHODS

We measured the following parameters in 88 obese children at baseline, at the end of a 1-year lifestyle intervention and 1-year later (=2 years after baseline): progranulin, bioactive leptin, body mass index-SD score (BMI-SDS), waist circumference, body fat based on skinfold measurements and bioimpedance analyses, lipids, transaminases, insulin resistance index homeostasis model assessment (HOMA), and blood pressure. As a control, we determined progranulin in 23 normal-weight children.

RESULTS

The progranulin concentrations did not differ significantly (P = .795) between obese and normal-weight children. Progranulin concentrations decreased significantly during and after the lifestyle intervention in children with and without decrease of BMI-SDS. There was no relationship between progranulin concentrations and pubertal stage or gender. Progranulin was not significantly associated with insulin resistance HOMA, parameters of the MetS or transaminases both in cross-sectional and longitudinal multiple linear regression analyses adjusted to multiple confounders. Progranulin was significantly, negatively related to age (b-coefficient -1.24 ± .97, P = .012, r² = .07).

CONCLUSIONS

Our data do not support the hypothesis that progranulin is an important link between obesity, insulin resistance, and MetS in childhood.

Fatty Acid Desaturase Involvement in Non-Alcoholic Fatty Liver Disease Rat Models: Oxidative Stress Versus Metalloproteinases

We investigated changes in fatty acid desaturases, D5D, D6D, D9-16D and D9-18D, and their relationship with oxidative stress, matrix metalloproteinases (MMPs) and serum TNF-alpha in two rat models of non-alcoholic fatty liver disease NAFLD. Eight-week-old male Wistar rats fed for 3 weeks with methionine-choline–deficient (MCD) diet and eleven-week-old Obese male Zucker rats were used. Serum levels of hepatic enzymes and TNF-alpha were quantified. Hepatic oxidative stress (ROS, TBARS and GSH content) and MMP-2 and MMP-9 (protein expression and activity) were evaluated. Liver fatty acid profiling, performed by GC-MS, was used for the quantification of desaturase activities. Higher D5D and D9-16D were found in Obese Zucker rats as well as an increase in D9-18D in MCD rats. D6D was found only in MCD rats. A negative correlation between D5D and D9-16D versus TBARS, ROS and TNF-alpha and a positive correlation with GSH were shown in fatty livers besides a positive correlation between D9-18D versus TBARS, ROS and TNF-alpha and a negative correlation with GSH. A positive correlation between D5D or D9-16D or D9-18D versus protein expression and the activity of MMP-2 were found. NAFLD animal models showed comparable serum enzymes. These results reinforce and extend findings on the identification of therapeutic targets able to counteract NAFLD disorder.

Clinical Applications of a Novel Selective PPARα Modulator, Pemafibrate, in Dyslipidemia and Metabolic Diseases

Fasting and postprandial hypertriglyceridemia is a risk factor for atherosclerotic cardiovascular diseases (ASCVD). Fibrates have been used to treat dyslipidemia, particularly hypertriglyceridemia, and low HDL-cholesterol (HDL-C). However, conventional fibrates have low selectivity for peroxisome proliferator-activated receptor (PPAR)α. Fibrates' clinical use causes side effects such as worsening liver function and elevating the creatinine level. Large-scale clinical trials of fibrates have shown negative results for prevention of ASCVD. To overcome these issues, the concept of the selective PPARα modulator (SPPARMα), with a superior balance of efficacy and safety, has been proposed. A SPPARMα, pemafibrate (K-877), was synthesized by Kowa Company, Ltd. for better efficacy and safety. Clinical trials conducted in Japan confirmed the superior effects of pemafibrate on triglyceride reduction and HDL-C elevation.

Conventional fibrates showed elevated liver function test values and worsened kidney function test values, while pemafibrate demonstrated improved liver function test values and was less likely to increase serum creatinine or decrease the estimated glomerular filtration rate. There were extremely few drug interactions even when it was used concomitantly with various statins. Furthermore, unlike many of the conventional fibrates that are renal excretory-type drugs, pemafibrate is excreted into the bile, so it can be safely used even in patients with impaired renal function and there is no increase in its blood concentration.

This novel SPPARMα, pemafibrate, has superior benefit-risk balance compared to conventional fibrates and can be used for patients for whom it was difficult to use existing fibrates, including those who are taking statins and those with renal dysfunction. A large-scale trial PROMINENT using pemafibrate for patients with type 2 diabetes is in progress. In the current review, the latest data on pemafibrate will be summarized.

Changes in peroxisome proliferator-activated receptor alpha target gene expression in peripheral blood mononuclear cells associated with non-alcoholic fatty liver disease

Objective

To identify differences in the expression of peroxisome proliferator-activated receptor alpha (PPARα) target genes in human peripheral blood mononuclear cells (PBMCs) associated with non-alcoholic fatty liver disease (NAFLD) among Chinese individuals.

Methods

Thirty healthy subjects were selected as the control group (CN), and 43 patients newly diagnosed with NAFLD were subdivided into two groups, non-obese group (NF, n = 21) and obese group (OF, n = 22). Expression of PPARα and its target genes was determined in PBMCs. The levels of liver cell damage markers, total cholesterol (TC), triglyceride (TG), free fatty acids (FFA), glucose, and insulin were determined in serum.

Results

Compared to the CN group, the blood pressure and homeostasis model assessment for insulin resistance (HOMA-IR) were increased in the other groups (P < 0.05), while the systolic blood pressure (SBP) and liver cell damage markers were significantly increased in the OF group (P < 0.05). In the OF group, PPARα target gene expression was 2.03–3.31 times higher than that in the CN group, and a negative correlation was found between PPARα target gene expression and abdominal circumference (AC), body mass index (BMI), diastolic blood pressure (DBP). Additionally, solute carrier family 25 (carnitine/acylcarnitine translocase) member 20 (SLC25A20) and acyl-coenzyme A dehydrogenase 2 long chain (ACADVL) were negatively correlated with HOMA-IR; PPARα, acetyl-coenzyme A dehydrogenase 2 (ACAA2), and carnitine palmitoyltransferase 1A (CPT1A) were positively correlated with HOMA-IR.

Conclusion

There is an up-expression of PPARα target genes in the PBMCs of NAFLD patients, possibly leading to changes in β-oxidation and insulin resistance.

Comparative Evaluation of the Fracture Resistance of Two Different Fiber-reinforced Composite Restorations with Particulate Filler Composite Restorations

Uncomplicated crown fractures are the most common form of traumatic dental injuries (TDIs) in children affecting their personal and social well-being.

Clinical, Radiological, and Histological Assessment of Magnetic Nanoparticles as Pulpotomy Medicament in Primary Molars

Aim and objectives

Aim of the study was to evaluate the success of magnetic nanoparticles (MNPs) as pulpotomy medicament by clinical, radiologic, and histological assessment in primary molars.

Materials and methods

The sample included 30 primary molars from 25 children aged between 3 and 9 years requiring pulpotomy treatment. Pulpotomy was carried out with MNPs. The teeth were evaluated after a period of 3, 6, and 12 months clinically and with the aid of radiographs. After 1 year, 10 teeth were extracted for histological evaluation under field emission scanning electron microscope (FE-SEM; ZEISS, Model No. Supra 55vp).

Results

Of the samples, 98% showed clinical success rate with absence of pain, swelling, mobility, and abscess formation. After 3 months, 98% radiological success with absence of periodontal ligament widening, root resorption, and inter-radicular radiolucency was noted. Histological examination carried out under FE-SEM revealed a zone of odontoblastic proliferation at the interface between MNPs and odontoblastic layer of pulp and viable pulpal cells from the canal orifice till apical foramen.

Conclusion

Magnetic nanoparticles can be recommended as an effective pulpotomy medicament with hard tissue barrier formation and preservation of vitality of remaining radicular pulp.

How to cite this article: Konyala HR, Mareddy AR, Puppala N, Reddy NV, Mallela MK, Susheela KP. Clinical, Radiological, and Histological Assessment of Magnetic Nanoparticles as Pulpotomy Medicament in Primary Molars. Int J Clin Pediatr Dent 2018;11(4):283-287.

Evaluation of Surgical Options for Supernumerary Teeth in the Anterior Maxilla

Aim

The purpose of this study was to evaluate the surgical options for supernumerary teeth (SNT) in the premaxillary region of children.

Materials and methods

A total of 69 patients with 82 partially or completely formed SNT in the anterior maxillary region were identified over a 3-year period. All selected patients were assessed for the number, location, and family history of SNT, damage to adjacent roots, and associated symptoms. The surgical approaches used for removal were recorded. Postoperative clinical sequelae (loss of vitality, periodontal problems, pain, bleeding, and enanthema) were evaluated.

Results

A total of 43, 30, and 9 SNT were extracted with palatal, buccal, and bicortical approaches respectively. Peri-odontal and vitality assessments revealed no problems in adjacent teeth at 6 months after surgery. Postoperative pain was within acceptable levels in all patients and subsided within 3 to 7 days. Mild postoperative bleeding occurred in eight patients. Enanthema subsided within 10 days in all patients.

Conclusion

Our results suggest that early diagnosis and appropriate surgical treatment of SNT are important to decrease the risk of clinical complications.

How to cite this article: Maddalone M, Rota E, Amosso E, Porcaro G, Mirabelli L. Evaluation of Surgical Options for Supernumerary Teeth in the Anterior Maxilla. Int J Clin Pediatr Dent 2018;11(4):294-298.

RAGE deficiency does not affect non-alcoholic steatohepatitis and atherosclerosis in Western type diet-fed Ldlr-/- mice

Non-alcoholic fatty liver disease is a spectrum of liver diseases ranging from steatosis only to non-alcoholic steatohepatitis (NASH). The latter is characterized by hepatic inflammation, which increases the risk of cardiovascular disease. It is poorly understood which factors contribute to the onset of hepatic inflammation characterizing the progression from steatosis to NASH. Previously, we demonstrated increased advanced glycation endproducts (AGEs) in the livers of NASH patients. We hypothesise that AGEs play a key role in NASH development by activating their proinflammatory receptor, RAGE. RAGE-deficient mice and wildtype littermates, both on Ldlr^−/− background, were fed a Western type diet (WTD) for 3 or 12 weeks. Flow cytometry, histology, gene expression and AGE measurements were performed to evaluate the effects of RAGE deficiency. RAGE-deficient mice displayed reduced weight gain and visceral fat expansion compared to control mice. No difference in adipose tissue inflammation was observed between groups. RAGE deficiency did not affect WTD-induced monocytosis, circulating lipids or hepatic steatosis. WTD-induced hepatic neutrophil and macrophage accumulation and atherosclerotic plaque development was comparable between control and RAGE-deficient mice. No difference in AGE levels was observed. RAGE does not seem to play a major role in the development of NASH or atherosclerosis in a hyperlipidemic mouse model.

P465L-PPARγ mutation confers partial resistance to the hypolipidaemic action of fibrates

AIMS

Familial partial lipodystrophic syndrome 3 (FPLD3) is associated with mutations in the transcription factor PPARγ. One of these mutations, the P467L, confers a dominant negative effect. We and others have previously investigated the pathophysiology associated with this mutation using a humanized mouse model that recapitulates most of the clinical symptoms observed in patients who have been phenotyped under different experimental conditions. One of the key clinical manifestations observed, both in humans and mouse models, is the ectopic accumulation of fat in the liver. With this study we aim to dissect the molecular mechanisms that contribute to the excessive accumulation of lipids in the liver and characterize the negative effect of this PPARγ mutation on the activity of PPARα in vivo when activated by fibrates.

MATERIAL AND METHODS

P465L-PPAR mutant and wild-type mice were divided into 8 experimental groups, 4 different conditions per genotype. Briefly, mice were fed a chow diet or a high-fat diet (HFD 45% Kcal from fat) for a period of 28 days and treated with WY14643 or vehicle for five days before culling. At the end of the experiment, tissues and plasma were collected. We performed extensive gene expression, fatty acid composition and histological analysis in the livers. The serum collected was used to measure several metabolites and to perform basic lipoprotein profile.

RESULTS

P465L mice showed increased levels of insulin and free fatty acids (FFA) as well as increased liver steatosis. They also exhibit decreased levels of very low density lipoproteins (VLDL) when fed an HFD. We also provide evidence of impaired expression of a number of well-established PPARα target genes in the P465L mutant livers.

CONCLUSION

Our data demonstrate that P465L confers partial resistance to the hypolipidemic action of fibrates. These results show that the fatty liver phenotype observed in P465L mutant mice is not only the consequence of dysfunctional adipose tissue, but also involves defective liver metabolism. All in all, the deleterious effects of P465L-PPARγ mutation may be magnified by their collateral negative effect on PPARα function.

Effect of a Papain-based Chemomechanical Agent on Structure of Dentin and Bond Strength: An in vitro Study

Aim

To evaluate the microtensile bond strength of teeth restored with packable composite after removing caries with three chemomechanical caries removal agents (Carisolv, Papacarie and Carie-care) and also to analyze its effect on chemical composition of dentin using energy-dispersive X-ray (EDX) analysis.

Design

A total of 40 carious molars with 1 to 1.5 mm of remaining dentin were selected and divided into four groups of 20 each. Group I (control)—bur, group II—Carisolv, group III—Papacarie, group IV—Carie-care. A total of 15 samples from each group were restored with composite; 1 mm thick sections were made and were debonded under tensile load. Remaining five samples from each group were subjected to EDX for elemental analysis of dentin surface.

Results

No statistically significant difference in the bond strength values and Ca/P ratio was observed between control group and three chemomechanical agents tested in the study.

Conclusion

None of the chemomechanical agents tested in the study adversely affected the bond strength of composite resin to caries-affected dentin. Therefore, newer papain-based chemomechanical agent Carie-care can be considered as an equally effective economical alternative to commonly used agents Carisolv and Papacarie.

How to cite this article: Nair S, Nadig RR, Pai VS, Gowda Y. Effect of a Papain-based Chemomechanical Agent on Structure of Dentin and Bond Strength: An in vitro Study. Int J Clin Pediatr Dent 2018;11(3):161-166.

Prevalence of Deleterious Oral Habits among 3- to 5-year-old Preschool Children in Bhubaneswar, Odisha, India

Aim

Oral habits during and beyond preschool age are one of the important etiological factors in developing malocclusion and other ill effects on orofacial structures. The objective of the present study was to know the prevalence of deleterious oral habits among 3- to 5-year-old preschool children in Bhubaneswar, Odisha, India.

Materials and methods

This cross-sectional study was conducted among preschool children, in the age group of 3 to 5 years in the city of Bhubaneswar, Odisha, India. To carry out this study, six private schools, two from each of the three electoral constituency, were selected using cluster sampling technique. A total of 500 students, studying in LKG and UKG and their respective mothers/caregivers were selected for the study as per the inclusion/exclusion criteria. Prevalence of different oral habits in children was calculated from the data obtained. Using Statistical Package for the Social Sciences (SPSS), version 17.0 software, Chi-square test was applied to compare the differences present between boys and girls and their significant values (p < 0.05).

Results

The result of this study showed a high prevalence of oral habits (36%) among preschool children in Bhubaneswar, Odisha, India. Lip biting was found to be the most prevalent habit (13.4%), followed closely by thumb sucking (12.8%), bruxism (12.8%), and mouth breathing (11%).

Conclusion

The study revealed a great dearth of a well-established dental education program for preschool children as well as their parents, caretakers, teachers, and pediatricians in order to provide an effective and timely care to the children.

How to cite this article: Dhull KS, Verma T, Dutta B. Prevalence of Deleterious Oral Habits among 3- to 5-year-old Preschool Children in Bhubaneswar, Odisha, India. Int J Clin Pediatr Dent 2018;11(3):210-213.

Foreign Body causing Displacement of Immature Fractured Apical Root Fragment: An Unusual Case Report

Trauma is a common cause of fractured teeth with exposed canals in growing children. These children use foreign bodies like stapler pin, lead pencil, nail, etc., to explore the canal of fractured tooth. Sometimes, these foreign objects may get stuck in the canal, which the children do not reveal to their parents because of fear. These foreign objects may act as a potential source of infection. We herewith present a case of a 12-year-old boy who presented with a stick lodged in the root canal of maxillary right lateral incisor along with the displaced fractured tooth segment at the apex and the associated management. How to cite this article: Moda A, Singla R, Agrawal PM. Foreign Body causing Displacement of Immature Fractured Apical Root Fragment: An Unusual Case Report. Int J Clin Pediatr Dent 2018;11(3):247-249.

A Comparative Evaluation of Time-dependent Changes on the Surface Hardness of Bulk Cure Composites: An in vitro Study

Objectives

The objective of this in vitro study was to assess the surface hardness through Vickers hardness (VH) test of one conventional hybrid resin composites (Filtek Z350), compared with that of two bulk cure resin composites (SDR™, Tetric N Ceram®).

Materials and methods

Twenty specimens of each material were prepared in cylindrical aluminum molds with an internal diameter of 5 mm and depth of 4 mm, 10 (incremental curing) and 10 (bulk curing).

The surface of each specimen was covered with a transparent plastic matrix strip before light curing with conventional visible light for 40 seconds. The specimens thus obtained were stored in deionized water and transferred to an incubator at 37°C for 24 hours to simulate clinical conditions. After 24 hours, the microhardness of each specimen was measured using a Vickers indenter, with a load of 100 gm and dwell time of 15 seconds (HV 0.2/40).

The specimens were further subjected to VH test in an interval of 7, 30, and 90 days. The data were subjected to statistical analysis—Student’s t test, analysis of variance, and post hoc Tukey’s test.

Results

The present study showed that SDR™ in bulk curing showed consistently greater value of hardness and was comparable to traditional incremental cured Filtek Z350, highlighting the advantages of the new SDR technology.

How to cite this article: Sarma A, Nagar P. A Comparative Evaluation of Time-dependent Changes on the Surface Hardness of Bulk Cure Composites: An in vitro Study. Int J Clin Pediatr Dent 2018;11(3):183-187.

A Comparative Study to evaluate Parent's Ability to assess Dental Fear in their 6- to 10-year-old Children using Children's Fear Survey Schedule-Dental Subscale

Aim

Parental presence often provides unique challenge in dental operatory and is directly related to the quality dental treatment. The present study was done to investigate parent's ability to assess dental anxiety of their 6- to 10-year-old child and to determine how parent's and children's fear assessments correlate with each other.

Materials and methods

Prior to dental treatment, 94 child-parent combinations were included to complete Children's Fear Survey Schedule-Dental Subscale (CFSS-DS) questionnaire, and Frankl score was assigned to children during treatment by operator.

Results

Mean dental anxiety score reported by the children was 27.74, whereas by their parents was 39.64. There was a poor consistency of parents to predict their child dental fear (p < 0.05). Parents reported higher dental fear for their children.

Conclusion

Parents assessment of their child's fear may vary in accordance to factors, including their own dental fear. Such input may prevent dentists from establishing an accurate association with the child's patient.How to cite this article: Malhotra R, Gandhi K, Kumar D, Ahuja S, Kapoor R, Sahni A. A Comparative Study to evaluate Parent's Ability to assess Dental Fear in their 6- to 10-year-old Children using Children's Fear Survey Schedule-Dental Subscale. Int J Clin Pediatr Dent 2018;11(3):205-209.

Effects of free omega-3 carboxylic acids and fenofibrate on liver fat content in patients with hypertriglyceridemia and non-alcoholic fatty liver disease: A double-blind, randomized, placebo-controlled study

BACKGROUND

Treatment with omega-3 fatty acids and fenofibrates reduces serum triglyceride levels, but few studies have compared the effect of these agents on liver fat.

OBJECTIVE

The aim of the EFFECT I trial (NCT02354976) was to determine the effects of free omega-3 carboxylic acids (OM-3CA) and fenofibrate on liver fat in overweight or obese individuals with non-alcoholic fatty liver disease and hypertriglyceridemia.

METHODS

Seventy-eight patients were randomized to receive oral doses of 4 g OM-3CA (n = 25), 200 mg fenofibrate (n = 27), or placebo (n = 26) for 12 weeks in a double-blind, parallel-group study. Liver proton density fat fraction (PDFF) and volume, pancreas volume, and adipose tissue volumes were assessed by magnetic resonance imaging.

RESULTS

Changes in liver PDFF at 12 weeks were not significantly different across treatment groups (relative changes from baseline: placebo, +4%; OM-3CA, -2%; and fenofibrate, +17%). The common PNPLA3 genetic polymorphism (I148M) did not significantly influence the effects of OM-3CA or fenofibrate on liver PDFF. Fenofibrate treatment significantly increased liver and pancreas volumes vs placebo treatment, and the changes in liver and pancreas volumes were positively correlated (rho 0.45, P = .02). Total liver fat volume increased significantly in patients using fenofibrate vs OM-3CA (+23% vs -3%, P = .04). Compared with OM-3CA, fenofibrate increased total liver fat and liver volume. Serum triglycerides decreased with OM-3CA (-26%, P = .02) and fenofibrate (-38%, P < .001) vs placebo. In contrast to OM-3CA, fenofibrate reduced plasma docosahexaenoic acid levels and increased plasma acetylcarnitine and butyrylcarnitine levels, estimated delta-9 desaturase activity and the concentration of urine F2-isoprostanes.

CONCLUSIONS

OM-3CA and fenofibrate reduced serum triglycerides but did not reduce liver fat. Fenofibrate increased total liver volume and total liver fat volume vs OM-3CA, indicating a complex effect of fenofibrate on human hepatic lipid metabolism.

Adipocytokine Regulation and Antiangiogenic Activity Underlie the Molecular Mechanisms of Therapeutic Effects of Phyllanthus niruri against Non-Alcoholic Fatty Liver Disease

The growth of adipose tissues is considered angiogenesis-dependent during non-alcoholic fatty liver disease (NAFLD). We have recently reported that our standardized 50% methanolic extract (ME) of Phyllanthus niruri (50% ME of P. niruri) has alleviated NAFLD in Sprague⁻Dawley rats. This study aimed to assess the molecular mechanisms of action, and to further evaluate the antiangiogenic effect of this extract. NAFLD was induced by eight weeks of high-fat diet, and treatment was applied for four weeks. Antiangiogenic activity was assessed by aortic ring assay and by in vitro tests. Our findings demonstrated that the therapeutic effects of 50% ME among NAFLD rats, were associated with a significant increase in serum adiponectin, reduction in the serum levels of RBP4, vaspin, progranulin, TNF-α, IL-6, and significant downregulation of the hepatic gene expression of PPARγ, SLC10A2, and Collα1. Concomitantly, 50% ME of P. niruri has exhibited a potent antiangiogenic activity on ring assay, cell migration, vascular endothelial growth factor (VEGF), and tube formation, without any cytotoxic effect. Together, our findings revealed that the protective effects of P. niruri against NAFLD might be attributed to its antiangiogenic effect, as well as to the regulation of adipocytokines and reducing the expression of adipogenic genes.

Role of peroxisome proliferator-activated receptors in non-alcoholic fatty liver disease inflammation

Overweight and obesity have been identified as the most important risk factors for many diseases, including cardiovascular disease, type 2 diabetes and lipid disorders, such as non-alcoholic fatty liver disease (NAFLD). The metabolic changes associated with obesity are grouped to define metabolic syndrome, which is one of the main causes of morbidity and mortality in industrialized countries. NAFLD is considered to be the hepatic manifestation of metabolic syndrome and is one of the most prevalent liver diseases worldwide. Inflammation plays an important role in the development of numerous liver diseases, contributing to the progression to more severe stages, such as non-alcoholic steatohepatitis and hepatocellular carcinoma. Peroxisome proliferator-activated receptors (PPARs) are binder-activated nuclear receptors that are involved in the transcriptional regulation of lipid metabolism, energy balance, inflammation and atherosclerosis. Three isotypes are known: PPAR-α, PPARδ/β and PPAR-γ. These isotypes play different roles in diverse tissues and cells, including the inflammatory process. In this review, we discuss current knowledge on the role PPARs in the hepatic inflammatory process involved in NAFLD as well as new pharmacological strategies that target PPARs.

Validity and Reliability of the Hindi Version of the Modified Child Perceptions Questionnaire 11 to 14

Introduction

The study was conceived to formulate a tool to evaluate child perceptions related to oral health in 11- to 14-year-olds tailor-made for Indian children in Hindi. The original child perceptions questionnaire (CPQ_11-14) was translated into Hindi and it was tested for validity and reliability.

Materials and methods

The original CPQ_11-14 was translated into Hindi and some questions were rephrased to suit the sociocultural situation in India. The domains of self-esteem and psychological well-being were added to the questionnaire to broaden the scope of parameters to thoroughly assess the impact on child perceptions toward oral health. The English and Hindi versions of the CPQ_11-14 were administered during the first visit to test for validity and the children were recalled after 1 week and administered the Hindi questionnaire again after 1 week to check for reliability.

Results

The results showed significant positive correlation between oral symptoms, decayed, missing and filled teeth (DMFT) functional limitation and malocclusion. The mean functional limitation score was found to be higher in subjects with malocclusion in both the English and Hindi questionnaires. The test-retest samples were evaluated using the paired t-test and showed no significant difference between the first and second administration which suggested good reliability.

Conclusion

The translated and modified Hindi CPQ_11-14 was found to be valid and highly reliable for use in India. The adaptation of the original questionnaire by modifying certain questions to suit the Indian condition was found to be culturally relevant.

How to cite this article: Kumar P, Mandanna DCM, Londhe SM, Sharma M. Validity and Reliability of the Hindi Version of the Modified Child Perceptions Questionnaire 11 to 14. Int J Clin Pediatr Dent 2018;11(4):271-276.

Comparative Evaluation of Effects of Triphala, Garlic Extracts, and Chlorhexidine Mouthwashes on Salivary Streptococcus mutans Counts and Oral Hygiene Status

Aims and objectives

To determine and compare the effect of triphala, chlorhexidine gluconate, and garlic extract mouthwash on salivary Streptococcus mutans count and the oral hygiene status.

Materials and methods

Sixty children aged 9 to 12 years were randomly allocated into the study groups of triphala mouthwash, chlorhexidine mouthwash, garlic extracts mouth-wash, and distilled water mouthwash. Examination included decayed, missing, and filled teeth (dmft)/decayed, missing, filled surface (dmfs) and DMFT/DMFS, plaque index, and S. mutans count on days 1, 15, and 30.

Results

The results were statistically analyzed using Friedman test, Wilcoxon signed rank, repeated-measures analysis of variance (ANOVA), paired t-test, one-way ANOVA, post hoc Tukey’s honestly significant different (HSD), Kruskal–Wallis test, and Mann-Whitney test; all calculations were done by MEDCALC software 14.0.0 version.

Discussion

Streptococcus mutans count had significant reductions using different mouthwashes at 15 days, but the chlorhexidine group showed significant difference from the remaining three groups. Intergroup comparison for plaque index scores of triphala, chlorhexidine, and garlic groups was similar in preventing plaque build-up during the 15 days of mouthwash use.

Conclusion

All the three mouthwashes containing triphala, chlorhexidine gluconate, and garlic were comparably efficient in reducing the salivary S. mutans count as well as in limiting plaque score; however, chlorhexidine was the most effective in this aspect. In comparison of the two natural ingredients, Triphala is more effective in its antimicrobial effect.

How to cite this article: Padiyar B, Marwah N, Gupta S, Padiyar N. Comparative Evaluation of Effects of Triphala, Garlic Extracts, and Chlorhexidine Mouthwashes on Salivary Streptococcus mutans Counts and Oral Hygiene Status. Int J Clin Pediatr Dent 2018;11(4):299-306.

Comparative Evaluation of Mucosal Vibrator with Topical Anesthetic Gel to reduce Pain during Administration of Local Anesthesia in Pediatric Patients: An in vivo Study

Introduction

Usually discomfort and pain are associated with dental work, especially for young patients. Pain control can be achieved by using anesthesia. Sight of injection can terrify any patient and if the patient is a child it is really difficult to convince them for injections. Alternatives to injections have been explored. Pediatric dentists are using anesthesia in the form of jelly and patch. Recently, the concept of mucosal vibration has been put forward to enhance the effectiveness of local anesthesia.

Aim

The aim of the present study was to compare and evaluate the effectiveness of lignocaine jelly and mucosal vibration in reducing pain during administration of local anesthesia in pediatric dental patients.

Materials and methods

Thirty children in the age group 6 to 11 years who required bilateral anesthesia for dental treatment in mandible were selected for this study. Pain was compared using Wilcoxon signed-rank test at the time of injection using Sound, Eye, Motor (SEM) scale as objective criteria and facial pain rating (FPR) scale as subjective criteria after administration of injection by a trained assistant who was blinded to the procedure.

Results

Local anesthetic injection along with mucosal vibration resulted in significantly less pain (p = 0.001) in comparison with the injections without the use of mucosal vibration.

Conclusion

The result shows that mucosal vibration can be used as an effective means to reduce the intensity of pain during local anesthetic injection in dentistry.

How to cite this article: Tandon S, Kalia G, Sharma M, Mathur R, Rathore K, Gandhi M. Comparative Evaluation of Mucosal Vibrator with Topical Anesthetic Gel to reduce Pain during Administration of Local Anesthesia in Pediatric Patients: An in vivo Study. Int J Clin Pediatr Dent 2018;11(4):261-265.

Accelerating Treatment of Skeletal Class II Malocclusion using Fixed Twin Block Appliances

Background

Patients with class II malocclusion generally seek orthodontic treatment for esthetic concern. Various myo-functionl appliances can be used for the treatment of skeletal as well as the dental malocclusion in a growing patient. Among various functional appliances, twin block appliance is most commonly used due to better patient compliances. It redirects the mandibular growth to correct the maxillomandibular relationship, enhancing facial esthet ics. This article presents a modified design of the twin block appliance which is less bulky, more esthetic, can be used concurrently with fixed orthodontic appliance, and is easily accepted by uncooperative patients.

Case summary

An 11-year-old-boy, who presented himself with a skeletal class II malocclusion, was treated with simultaneous use of fixed twin block along with fixed orthodontic appliance to correct both the skeletal and dental malocclusion. The twin block design was modified to have a better compatibility with the fixed orthodontic appliance.

How to cite this article: Pattanaik S, Puvvula N, Mohammad N. Accelerating Treatment of Skeletal Class II Malocclusion using Fixed Twin Block Appliances. Int J Clin Pediatr Dent 2018;11(2):146-150.