Soat2 ties cholesterol metabolism to β-oxidation and glucose tolerance in male mice

Bisphenol S Exposure and MASLD: A Mechanistic Study in Mice

BACKGROUND

Bisphenol S (BPS) is a substitute for bisphenol A in various commercial products and is increasingly used globally due to restrictions on bisphenol A usage. Consequently, there are increasing public health concerns that substantial effects mediated by synthetic chemicals may impact human health. Recently, epidemiology studies reported associations between bisphenol exposure and nonalcoholic fatty liver disease [metabolic dysfunction-associated steatotic liver disease (MASLD)]. However, the causal relationship and the molecular mechanisms affecting hepatocellular functions are still unknown.

OBJECTIVES

Our study aimed to understand the molecular mechanism by which BPS exposure caused hepatic lipid deposition.

METHODS

C57BL/6J mice were exposed to BPS for 3 months, and its effects were assessed by histology. RNA sequencing (RNA-seq), assay for transposase-accessible chromatin with high-throughout sequencing (ATAC-seq), and cleavage under targets and tagmentation (CUT&Tag) were used to investigate mechanistic details. ATF3 liver-specific knockout mice and cells were used to validate its functions in BPS-induced hepatotoxicity.

RESULTS

Here, mice that were chronically exposed to BPS showed significant lipid deposition in the liver and dyslipidemia and were predisposed to MASLD, accompanied with a reprogrammed liver transcriptional network and chromatin accessibility that was enriched for the Atf3 binding motif. Comparing to the control group, we identified numerous differential Atf3 binding sites associated with signaling pathways integral to lipid catabolism and synthesis in the BPS exposure group, resulting in a drastic surge in lipid accumulation. Moreover, knocking out Atf3 in vitro and in vivo significantly attenuates BPS-induced hepatic lipid accumulation via the regulation of chromatin accessibility and gene expression. Besides, inhibiting JunB also eliminates BPS-induced Atf3 upregulation and lipid accumulation.

CONCLUSION

Our study reveals a novel mechanism, through which BPS upregulates JunB and Atf3 to impair hepatic lipid metabolism, and provides new insights into the hepatotoxicity of BPS. https://doi.org/10.1289/EHP17057.

Novel molecular mechanisms of immune evasion in hepatocellular carcinoma: NSUN2-mediated increase of SOAT2 RNA methylation

BACKGROUND

Hepatocellular carcinoma (HCC) is a deadly malignancy known for its ability to evade immune surveillance. NOP2/Sun RNA methyltransferase family member 2 (NSUN2), an RNA methyltransferase involved in carcinogenesis, has been associated with immune evasion and energy metabolism reprogramming. This study aimed to examine the molecular mechanisms underlying the involvement of NSUN2 in immune evasion and metabolic reprogramming of HCC.

METHODS

Single-cell transcriptomic sequencing was applied to examine cellular composition changes, particularly immune cell dynamics, in HCC and adjacent normal tissues. Bulk RNA-seq and proteomics identified key genes and proteins. Methylation sequencing and methylated RNA immunoprecipitation (MeRIP) were carried out to characterize the role of NSUN2 in 5-methylcytosine (m5C) modification of sterol O-acyltransferase 2 (SOAT2). Clinical samples from 30 HCC patients were analyzed using reverse transcription-quantitative polymerase chain reaction and Western blotting. Gene expression was manipulated using CRISPR/Cas9 and lentiviral vectors. In vitro co-culture models and metabolomics were used to study HCC cell-T cell interactions, energy metabolism, and immune evasion. Tumor growth in an orthotopic mouse model was monitored by bioluminescence imaging, with subsequent measurements of tumor weight, volume, and immunohistochemical staining.

RESULTS

Single-cell transcriptomic analysis identified a marked increase in malignant cells in HCC tissues. Cell communication analysis indicated that tumor cells might promote cancer progression by evading immune clearance. Multi-omics analyses identified NSUN2 as a key regulator in HCC development. MeRIP confirmed that NSUN2 facilitated the m5C modification of SOAT2. Analysis of human HCC tissue samples demonstrated pronounced upregulation of NSUN2 and SOAT2, along with elevated m5C levels in HCC tissues. In vitro experiments uncovered that NSUN2 augmented the reprogramming of energy metabolism and repressed the activity and cytotoxicity of CD8+ T cells, contributing to immune evasion. In vivo studies further substantiated the role of NSUN2 in fostering immune evasion and tumor formation of HCC by modulating the m5C modification of SOAT2.

CONCLUSIONS

The findings highlight the critical role of NSUN2 in driving HCC progression through the regulation of m5C modification on SOAT2. These findings present potential molecular markers for HCC diagnosis and therapeutic targets for its treatment.

Benfuracarb impairs zebrafish swim bladder development via the JNK2 pathway mediated inhibition of autophagy

Benfuracarb is widely utilized for crop protection due to its effective pest control properties; however, little information is available regarding its adverse effects and possible molecular mechanisms in fish development. In the present study, benfuracarb exposure caused defects in the development and inflation of the swim bladder, as well as in the lipid metabolism of zebrafish larvae. Compared with the control, key genes involved in swim bladder development, lipid metabolism, surfactant proteins and autophagy were altered in response to benfuracarb exposure. Furthermore, potential targets of benfuracarb were identified using network toxicology and molecular docking, with c-Jun N-terminal kinase 2 (JNK2 encoded by mapk9) predicted as a critical target. Moreover, the JNK family activator anisomycin was observed to mitigate the inhibitory effects of benfuracarb on zebrafish swim bladder inflation, as well as on the expression of autophagy-related genes, suggesting that benfuracarb may inhibit swim bladder development and inflation by downregulating the JNK2 signaling pathway. Overall, this study suggests that the swim bladder might serve as a potential target organ for benfuracarb toxicity in zebrafish, providing valuable insights for assessing the environmental risks of benfuracarb.

USP14-Dependent IGF1R Aggravates High Glucose-Induced Diabetic Retinopathy by Upregulating BAP1

Diabetic retinopathy (DR) is a microvascular complication of diabetes. Insulin-like growth factor 1 receptor (IGF1R) has been implicated in the pathogenesis of DR; however, the underlying mechanism remains unclear. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to assess IGF1R mRNA expression. Western blotting assays were performed to analyze the protein expression of IGF1R, ubiquitin-specific peptidase 14 (USP14), and BRCA1-associated protein 1 (BAP1). Cell viability, apoptosis, interleukin-1 beta (IL-1β), and tumor necrosis factor-alpha (TNF-α) levels were analyzed using cell counting kit-8 assay, flow cytometry, and enzyme-linked immunosorbent assays, respectively. Fluorescent microscopy and flow cytometry were performed for reactive oxygen species (ROS) level assessment, and colorimetric assays for iron (Fe2+) and glutathione (GSH) levels. Co-immunoprecipitation assays and/or colocalization techniques were employed to validate the association of IGF1R with USP14 and BAP1. Treatment with high glucose (HG) increased the protein expression of IGF1R, USP14, and BAP1 in ARPE-19 cells. Silencing of IGF1R mitigated HG-induced apoptosis, inflammatory response, and ferroptosis in ARPE-19 cells. USP14 was found to stabilize IGF1R protein expression through deubiquitination. Overexpression of USP14 exacerbated HG-induced cellular injury, whereas silencing of USP14 protected ARPE-19 cells by reducing IGF1R expression. Interaction between IGF1R and BAP1 was confirmed in ARPE-19 cells and IGF1R silencing protected cells from HG-induced injury by regulating BAP1 expression. Thus, USP14-dependent regulation of IGF1R expression and its interaction with BAP1 play a crucial role in the pathogenesis of high glucose-induced diabetic retinopathy.

Elucidating the mechanism of phthalates induced osteoporosis through network toxicology and molecular docking

OBJECTIVE

This study investigated the effects of plasticizers (phthalates) on the pathogenesis of osteoporosis (OP) and the associated molecular mechanisms, especially the interaction of plasticizers with key pathways.

METHODS

We performed differential expression analysis of different datasets by machine learning to identify target genes associated with OP. And, we also investigated the binding of plasticizers to target proteins using network toxicology and molecular docking techniques.

RESULTS

A total of 29 genes are potential targets associated with plasticizer-induced OP. Subsequently, machine learning analysis identified six core target genes as key genes for plasticizer-induced OP. Among them, the up-regulated genes were CKM and SOAT2, and the down-regulated genes were TACR3, SGK1, ERAP2, and MMP12 (P＜0.05). Molecular docking revealed the specific binding effect between plasticizers and target proteins.

CONCLUSION

This study demonstrates that plasticizers may influence the pathogenesis of OP by targeting specific genes and pathways. And the molecular docking simulations indicate a distinct binding specificity between plasticizers and target proteins. These results provide a foundation for further investigation into the mechanisms by which plasticizers affect bone health. Future research should focus on the dose-response relationship between plasticizer exposure and the risk of OP, and explore potential intervention measures to mitigate the adverse effects of plasticizers on bone health.

ELAVL1-dependent SOAT2 exacerbated the pancreatitis-like cellular injury of AR42J cells induced by hyperstimulation with caerulein

Pancreatitis is a severe inflammatory condition characterized by damage to the pancreas. Sterol o-acyltransferase 2 (SOAT2) has been reported to aggravate acute pancreatitis, however, the underlying mechanism remains to be elucidated. Rat pancreatic exocrine cells (AR42J) were treated with caerulein to induce pancreatitis-like cellular injury. Cell viability was determined using a cell counting kit-8 (CCK-8) assay, while cell proliferation was analyzed through a 5-Ethynyl-2'-deoxyuridine assay. Cell apoptosis was measured using flow cytometry, and enzyme-linked immunosorbent assays were performed to detect levels of pro-inflammatory cytokines IL-6 and TNF-α. Additionally, Fe2+ levels were analyzed using a colorimetric assay kit, reactive oxygen species (ROS) levels were assessed with a Cellular ROS Assay kit, and lipid peroxidation was measured using a malondialdehyde assay kit. Glutathione levels were analyzed with a detection assay. Protein and mRNA expression were evaluated through western blotting and quantitative real-time polymerase chain reaction, respectively. Furthermore, an RNA immunoprecipitation assay was conducted to investigate the association between ELAV-like RNA binding protein 1 (ELAVL1) and SOAT2. Actinomycin D assay was performed to explore the effect of ELAVL1 depletion on the transcript stability of SOAT2 mRNA. SOAT2 and ELAVL1 expression were upregulated in caerulein-exposed AR42J cells. Caerulein treatment induced pancreatitis-like cellular apoptosis, inflammatory response, ferroptosis, and cell proliferation inhibition. Silencing of SOAT2 protected against caerulein-induced AR42J cell injury. Moreover, ELAVL1 stabilized SOAT2 mRNA expression in AR42J cells. SOAT2 overexpression attenuated the effects induced by ELAVL1 silencing in caerulein-exposed AR42J cells. Additionally, ELAVL1 knockdown activated the NRF2/HO-1 pathway by downregulating SOAT2 expression in caerulein-exposed AR42J cells. SOAT2 silencing protected AR42J cells from caerulein-induced injury by inactivating the NRF2 pathway. In conclusion, ELAVL1-dependent SOAT2 exacerbated pancreatic exocrine cell injury by inactivating the NRF2/HO-1 pathway in pancreatitis. These findings provide new insights into the molecular mechanisms underlying pancreatitis and offer potential therapeutic targets for the treatment of this condition.

siRNA/CS-PLGA Nanoparticle System Targeting Knockdown Intestinal SOAT2 Reduced Intestinal Lipid Uptake and Alleviated Obesity

Effective inhibition of intestinal lipid uptake is an efficient strategy for the treatment of disorders related to lipid metabolism. Sterol O-acyltransferase 2 (SOAT2) is responsible for the esterification of free cholesterol and fatty acids into cholesteryl esters. We found that intestine-specific SOAT2 knockout (Soat2I-KO) mice was capable to prevent the development of dietary induced obesity due to reduced intestinal lipid absorption. Soat2 siRNA/CS-PLGA nanoparticle system was constructed to enable intestinal delivery and inhibition of Soat2. This nanoparticle system was composed of PLGA-block-PEG and chitosan specifically delivering Soat2 siRNAs into small intestines in mice, effectively inhibit intestinal lipid uptake and resolving obesity. In revealing the underlying mechanism by which intestinal SOAT2 regulating fatty acid uptake, enhanced CD36 ubiquitination degradation was found in enterocytes upon SOAT2 inhibition. Insufficient free cholesterol esterification promoted endoplasmic reticulum stress and recruitment of E3 ligase RNF5 to activate CD36 ubiquitination in SOAT2 knockdown enterocytes. This work demonstrates a potential modulatory function of intestinal SOAT2 on lipid uptake highlighting the therapeutic effect on obesity by targeting intestinal SOAT2, exhibiting promising translational relevance in the siRNA therapeutic-based treatment for obesity.

Integrative metagenomic and lipidomic analyses reveal alterations in children with obesity and after lifestyle intervention

Background

Despite emerging evidence linking alterations in gut microbiota to childhood obesity, the metabolic mechanisms linking gut microbiota to the lipid profile during childhood obesity and weight loss remain poorly understood.

Methodology

In this study, children with obesity were treated with lifestyle weight loss therapy. Metagenomics association studies and serum untargeted lipidomics analyses were performed in children with obesity and healthy controls before and after weight loss.

Main findings

We identified alterations in gut microbiota associated with childhood obesity, as well as variations in circulating metabolite concentrations. Children with obesity showed significant decreases in the levels of s-Rothia_kristinae and s-Enterobacter_roggenkampii, alongsige elevated levels of s-Clostridiales_bacterium_Marseille-P5551. Following weight loss, the levels of s-Streptococcus_infantarius and s-Leuconostoc_citreum increased by factors of 3.354 and 1.505, respectively, in comparison to their pre-weight loss levels. Correlation analyses indicated a significant positive relationship between ChE(2:0) levels and both with s-Lachnospiraceae_bacterium_TF09-5 and fasting glucose levels. CoQ8 levels were significantly negatively correlated with s-Rothia_kristinae and HOMA-IR.

Conclusion

We linked altered gut microbiota and serum lipid levels in children with obesity to clinical indicators, indicating a potential impact on glucose metabolism via lipids. This study contributes to understanding the mechanistic relationship between altered gut microbiota and childhood obesity and weight loss, suggesting gut microbiome as a promising target for intervention.

Clinical trial registration

https://www.chictr.org.cn/showproj.html?proj=178971, ChiCTR2300072179.

Lentinan Ameliorates β-Hydroxybutyrate-Induced Lipid Metabolism Disorder in Bovine Hepatocytes by Upregulating the Expression of Acetyl-coenzyme A Acetyltransferase 2

Ketosis in dairy cows is often accompanied by the dysregulation of lipid homeostasis in the liver. Acetyl-coenzyme A acetyltransferase 2 (ACAT2) is specifically expressed in the liver and is important for regulating lipid homeostasis in ketotic cows. Lentinan (LNT) has a wide range of pharmacological activities, and this study investigates the protective effects of LNT on β-hydroxybutyrate (BHBA)-induced lipid metabolism disorder in bovine hepatocytes (BHECs) and elucidates the underlying mechanisms. BHECs were first pretreated with LNT to investigate the effect of LNT on BHBA-induced lipid metabolism disorder in BHECs. ACAT2 was then silenced or overexpressed to investigate whether this mediated the protective action of LNT against BHBA-induced lipid metabolism disorder in BHECs. Finally, BHECs were treated with LNT after silencing ACAT2 to investigate the interaction between LNT and ACAT2. LNT pretreatment effectively enhanced the synthesis and absorption of cholesterol, inhibited the synthesis of triglycerides, increased the expression of ACAT2, and elevated the contents of very low-density lipoprotein and low-density lipoprotein cholesterol, thereby ameliorating BHBA-induced lipid metabolism disorder in BHECs. The overexpression of ACAT2 achieved a comparable effect to LNT pretreatment, whereas the silencing of ACAT2 aggravated the effect of BHBA on inducing disorder in lipid metabolism in BHECs. Moreover, the protective effect of LNT against lipid metabolism disorder in BHBA-induced BHECs was abrogated upon silencing of ACAT2. Thus, LNT, as a natural protective agent, can enhance the regulatory capacity of BHECs in maintaining lipid homeostasis by upregulating ACAT2 expression, thereby ameliorating the BHBA-induced lipid metabolism disorder.

Soat2 inhibitor avasimibe alleviates acute pancreatitis by suppressing acinar cell ferroptosis

Ferroptosis, characterized by lipid peroxidation, plays a significant role in the pathogenesis of acute pancreatitis (AP). While sterol O-acyltransferase 2 (Soat2) is known for its crucial regulatory role in cholesterol homeostasis, its involvement in the development of AP remains unreported. We conducted this study to identify the pivotal role of Soat2 in AP using transcriptomic databases. Subsequently, we confirmed its alterations through both in vitro and in vivo experimental models. Furthermore, we performed intervention with the Soat2 inhibitor avasimibe to evaluate pancreatic tissue pathology and serum enzymatic levels and observe inflammatory cell infiltration through immunohistochemistry. Additionally, changes in indicators related to ferroptosis were also observed. The results showed that in the AP mouse model, the protein and mRNA levels of Soat2 were significantly increased. Following avasimibe administration, there was a decrease in serum amylase levels, reduction in pancreatic tissue pathological damage, and attenuation of inflammatory cell infiltration. Furthermore, avasimibe administration resulted in downregulation of ferroptosis-related indicators. In conclusion, our findings suggest that the Soat2 inhibitor avasimibe protects against AP in mice through inhibition of the ferroptosis.

Characterizing defective lipid metabolism in the lateral septum of mice treated with olanzapine: implications for its side effects

Schizophrenia significantly impacts cognitive and behavioral functions and is primarily treated with second-generation antipsychotics (SGAs) such as olanzapine. Despite their efficacy, these drugs are linked to serious metabolic side effects which can diminish patient compliance, worsen psychiatric symptoms and increase cardiovascular disease risk. This study explores the hypothesis that SGAs affect the molecular determinants of synaptic plasticity and brain activity, particularly focusing on the lateral septum (LS) and its interactions within hypothalamic circuits that regulate feeding and energy expenditure. Utilizing functional ultrasound imaging, RNA sequencing, and weighted gene co-expression network analysis, we identified significant alterations in the functional connection between the hypothalamus and LS, along with changes in gene expression in the LS of mice following prolonged olanzapine exposure. Our analysis revealed a module closely linked to increases in body weight and adiposity, featuring genes primarily involved in lipid metabolism pathways, notably Apoa1, Apoc3, and Apoh. These findings suggest that olanzapine may influence body weight and adiposity through its impact on lipid metabolism-related genes in the LS. Therefore, the neural circuits connecting the LS and LH, along with the accompanying alterations in lipid metabolism, are likely crucial factors contributing to the weight gain and metabolic side effects associated with olanzapine treatment.

Subclinical ketosis leads to lipid metabolism disorder by downregulating the expression of acetyl-coenzyme A acetyltransferase 2 in dairy cows

Ketosis is a metabolic disease that often occurs in dairy cows postpartum and is a result of disordered lipid metabolism. Acetyl-coenzyme A (CoA) acetyltransferase 2 (ACAT2) is important for balancing cholesterol and triglyceride (TG) metabolism; however, its role in subclinical ketotic dairy cows is unclear. This study aimed to explore the potential correlation between ACAT2 and lipid metabolism disorders in subclinical ketotic cows through in vitro and in vivo experiments. In the in vivo experiment, liver tissue and blood samples were collected from healthy cows (CON, n = 6, β-hydroxybutyric acid [BHBA] concentration <1.0 mM) and subclinical ketotic cows (subclinical ketosis [SCK], n = 6, BHBA concentration = 1.2-3.0 mM) to explore the effect of ACAT2 on lipid metabolism disorders in SCK cows. For the in vitro experiment, bovine hepatocytes (BHEC) were used as the model. The effects of BHBA on ACAT2 and lipid metabolism were investigated via BHBA concentration gradient experiments. Subsequently, the relation between ACAT2 and lipid metabolism disorder was explored by transfection with siRNA of ACAT2. Transcriptomics showed an upregulation of differentially expression genes during lipid metabolism and significantly lower ACAT2 mRNA levels in the SCK group. Compared with the CON group in vivo, the SCK group showed significantly higher expression levels of peroxisome proliferator-activated receptor γ (PPARγ) and sterol regulator element binding protein 1c (SREBP1c) and significantly lower expression levels of peroxisome proliferator-activated receptor α (PPARα), carnitine palmitoyl-transferase 1A (CPT1A), sterol regulatory element binding transcription factor 2 (SREBP2), and 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR). Moreover, the SCK group had a significantly higher liver TG content and significantly lower plasma total cholesterol (TC) and free cholesterol content. These results were indicative of TG and cholesterol metabolism disorders in the liver of dairy cows with SCK. Additionally, the SCK group showed an increased expression of perilipin-2 (PLIN2), decreased expression of apolipoprotein B, and decreased plasma concentration of very low-density lipoproteins (VLDL) and low-density lipoproteins cholesterol (LDL-C) by downregulating ACAT2, which indicated an accumulation of TG in liver. In vitro experiments showed that BHBA induced an increase in the TG content of BHEC, decreased content TC, increased expression of PPARγ and SREBP1c, and decreased expression of PPARα, CPT1A, SREBP2, and HMGCR. Additionally, BHBA increased the expression of PLIN2 in BHEC, decreased the expression and fluorescence intensity of ACAT2, and decreased the VLDL and LDL-C contents. Furthermore, silencing ACAT2 expression increased the TG content; decreased the TC, VLDL, and LDL-C contents; decreased the expression of HMGCR and SREBP2; and increased the expression of SREBP1c; but had no effect on the expression of PLIN2. These results suggest that ACAT2 downregulation in BHEC promotes TG accumulation and inhibits cholesterol synthesis, leading to TG and cholesterol metabolic disorders. In conclusion, ACAT2 downregulation in the SCK group inhibited cholesterol synthesis, increased TG synthesis, and reduced the contents of VLDL and LDL-C, eventually leading to disordered TG and cholesterol metabolism.

DNA Methylation of Genes Participating in Hepatic Metabolisms and Function in Fetal Calf Liver Is Altered by Maternal Undernutrition during Gestation

This study aimed to elucidate the effects of maternal undernutrition (MUN) on epigenetic modification of hepatic genes in Japanese Black fetal calves during gestation. Using a previously established experimental design feeding the dams with 60% (LN) or 120% (HN) of their global nutritional requirements during the 8.5-month gestational period, DNA methylation in the fetal liver was analyzed with reduced representation bisulfite sequencing (RRBS). The promoters and gene bodies in the LN fetuses were hypomethylated compared to HN fetuses. Pathway analysis showed that the genes with DMR in the exon/intron in the LN group were associated with pathways involved in Cushing syndrome, gastric acid secretion, and aldosterone synthesis and secretion. Promoter hypomethylation in the LN group was frequently observed in genes participating in various signaling pathways (thyroid hormone, Ras/Rap1, PIK3-Akt, cAMP), fatty acid metabolism, and cholesterol metabolism. The promoter hypomethylated genes ALPL and GNAS were upregulated in the LN group, whereas the promoter hypermethylated genes GRB10 and POR were downregulated. The intron/exon hypomethylated genes IGF2, IGF2R, ACAD8, TAT, RARB, PINK1, and SOAT2 were downregulated, whereas the hypermethylated genes IGF2BP2, NOS3, and NR2F1 were upregulated. Collectively, MUN alters the promoter and gene body methylation of genes associated with hepatic metabolisms (energy, cholesterol, mitochondria) and function, suggesting an impact of altered gene methylation on the dysregulation of gene expression in the fetal liver.

Combining Dietary Intervention with Metformin Treatment Enhances Non-Alcoholic Steatohepatitis Remission in Mice Fed a High-Fat High-Sucrose Diet

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are serious health concerns for which lifestyle interventions are the only effective first-line treatment. Dietary interventions are effective in body weight reduction, but not in improving insulin sensitivity and hepatic lipid mobilization. Conversely, metformin increases insulin sensitivity and promotes the inhibition of de novo hepatic lipogenesis. In this study, we evaluated the metformin effectiveness in NASH prevention and treatment, when combined with dietary intervention in male mice fed a high-fat high-sucrose diet (HFHSD). Eighty 5-week-old C57BL/6J male mice were fed a chow or HFHSD diet and sacrificed at 20 or 40 weeks. The HFHSD-fed mice developed NASH after 20 weeks. Lipoprotein and lipidomic analyses showed that the changes associated with diet were not prevented by metformin administration. HFHSD-fed mice subject to dietary intervention combined with metformin showed a 19.6% body weight reduction compared to 9.8% in those mice subjected to dietary intervention alone. Lower hepatic steatosis scores were induced. We conclude that metformin should not be considered a preventive option for NAFLD, but it is effective in the treatment of this disorder when combined with dietary intervention.