Developmental origins of nonalcoholic fatty liver disease

Transcriptome analysis reveals hepatic disordered lipid metabolism, lipotoxic injury, and abnormal development in IUGR sheep fetuses due to maternal undernutrition during late pregnancy

Although lipid metabolism in fetal livers under intrauterine growth restriction (IUGR) conditions has been widely studied, the implications of maternal undernutrition on fetal hepatic lipid metabolism, lipotoxic injury, and abnormal development remain largely unknown. Therefore, this study investigated the effects of maternal undernutrition on disordered hepatic lipid metabolism, lipotoxic injury, and abnormal development in IUGR sheep fetuses using transcriptome analysis. Seventeen singleton ewes were randomly divided into three groups on day 90 of pregnancy: a control group (CG; 0.63 MJ metabolic energy/body weight (ME/BW)0.75/day, n = 5), maternal undernutrition group 1 (MU1; 0.33 MJ ME/BW0.75/day, n = 6), and maternal undernutrition group 2 (MU2; 0.20 MJ ME/BW0.75/day, n = 6). The fetuses were euthanized and recovered on day 130 of pregnancy. The levels of free fatty acids (FFA) in maternal blood (P < 0.01), fetal blood (P < 0.01), and fetal livers (P < 0.05) were increased in the MU1 and MU2 groups, but fetal hepatic triglyceride (TG) levels in the MU2 group (P < 0.01) and β-hydroxybutyrate levels in the MU1 and MU2 groups (P < 0.01) were decreased compared to the CG. Severe inflammatory cell infiltration and increased non-alcoholic fatty liver disease activity scores were observed in MU1 and MU2 fetuses (P < 0.01). Progressive deposition of fetal hepatic reticular fibers and collagen fibers in the fetal livers of the MU1 and MU2 groups and significant hepatic fibrosis were observed in the MU2 fetuses (P < 0.05). Gene set enrichment analysis showed that genes involved in lipid accumulation and FFA beta oxidation were downregulated in both MU groups compared to those in the controls. The fetal liver mRNA expression of the β-oxidation regulator, acetyl-CoA acetyltransferase 1, and the TCA regulator, isocitrate dehydrogenase were reduced in MU1 (P < 0.05) and MU2 (P < 0.01) fetuses, and downregulated mRNA expression of long chain fatty acid CoA ligase 1 (P < 0.05) and glycerol-3-phosphate acyltransferase (P < 0.01) was observed in MU2 fetuses. Differentially expressed genes (DEGs) in MU1 versus CG (360 DEGs) and MU2 versus CG (746 DEGs) were identified using RNA sequencing. Bioinformatics analyses of the 231 intersecting DEGs between MU1 versus CG and MU2 versus CG indicated that neutrophil extracellular traps (NETs) were induced and played a central role in fetal hepatic injury in IUGR sheep. Increased maternal blood myeloperoxidase (MPO) levels (P < 0.01), NE (Elane)-positive areas in fetal liver sections (P < 0.05), and fetal liver MPO protein expression (P < 0.01) were found in the MU1 and MU2 groups; however, MPO levels were reduced in the fetal membrane (P < 0.01) and fetal blood (P < 0.05) in the MU1 group, and in the maternal-fetal placenta and fetal blood in the MU2 group (P < 0.01). Analysis of gene expression trends in the intersecting DEGs between MU1 versus CG (129 DEGs) and MU2 versus CG (515 DEGs) further revealed that 30 hub genes were essential regulators of the G2/M cell cycle, all of which were associated with hepatocellular carcinoma. G0/G1 phase cells of the fetal liver were reduced in the MU1 (P < 0.05) and MU2 (P < 0.01) groups, whereas G2/M phase cells were elevated in the MU1 and MU2 groups (P < 0.01). The representatives of upregulated hub genes and fetal liver protein expression of maternal embryonic leucine zipper kinase and protein regulator of cytokinesis 1 were progressively enhanced in the MU1 and MU2 groups (P < 0.01), and topoisomerase II alpha protein expression in the MU2 group (P < 0.05), as expected. These results indicate that FFA overload, severe lipotoxic injury, and NETs were induced, and disease-promoting regulators of the G2/M cell cycle were upregulated in the fetal liver of IUGR sheep. These findings provide new insights into the pathogenesis of impaired hepatic lipid metabolism and abnormal development and the molecular origin of post-natal liver disease in IUGR due to maternal undernutrition. This information can support the development of new therapeutic strategies.

The effects of exposure to and timing of a choline-deficient diet during pregnancy and early postnatal life on the skeletal muscle transcriptome of the offspring

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD) is related to muscle loss, but the precise mechanism underlying this association remains unclear. The aim of the present study was thus to determine the influence of maternal fatty liver and dietary choline deficiency during pregnancy and/or lactation periods on the skeletal muscle gene expression profile among 24-day-old male rat offspring.

METHODS

Histological examination of skeletal muscle tissue specimens obtained from offspring of dams suffering from fatty liver, provided with proper choline intake during pregnancy and lactation (NN), fed a choline-deficient diet during both periods (DD), deprived of choline only during pregnancy (DN), or only during lactation (ND), was performed. The global transcriptome pattern was assessed using a microarray approach (Affymetrix® Rat Gene 2.1 ST Array Strip). The relative expression of selected genes was validated by real-time PCR (qPCR).

RESULTS

Morphological differences in fat accumulation in skeletal muscle related to choline supply were observed. The global gene expression profile was consistent with abnormal morphological changes. Mettl21c gene was overexpressed in all choline-deficient groups compared to the NN group, while two genes, Cdkn1a and S100a4, were downregulated. Processes of protein biosynthesis were upregulated, and processes related to cell proliferation and lipid metabolism were inhibited in DD, DN, and ND groups compared to the NN group.

CONCLUSIONS

Prenatal and early postnatal exposure to fatty liver and dietary choline deficiency leads to changes in the transcriptome profile in skeletal muscle of 24-day old male rat offspring and is associated with muscle damage, but the mechanism of it seems to be different at different developmental stages of life. Adequate choline intake during pregnancy and lactation can prevent severe muscle disturbance in the progeny of females suffering from fatty liver.

Developmental Programming of the Fetal Immune System by Maternal Western-Style Diet: Mechanisms and Implications for Disease Pathways in the Offspring

Maternal obesity and over/undernutrition can have a long-lasting impact on offspring health during critical periods in the first 1000 days of life. Children born to mothers with obesity have reduced immune responses to stimuli which increase susceptibility to infections. Recently, maternal western-style diets (WSDs), high in fat and simple sugars, have been associated with skewing neonatal immune cell development, and recent evidence suggests that dysregulation of innate immunity in early life has long-term consequences on metabolic diseases and behavioral disorders in later life. Several factors contribute to abnormal innate immune tolerance or trained immunity, including changes in gut microbiota, metabolites, and epigenetic modifications. Critical knowledge gaps remain regarding the mechanisms whereby these factors impact fetal and postnatal immune cell development, especially in precursor stem cells in bone marrow and fetal liver. Components of the maternal microbiota that are transferred from mothers consuming a WSD to their offspring are understudied and identifying cause and effect on neonatal innate and adaptive immune development needs to be refined. Tools including single-cell RNA-sequencing, epigenetic analysis, and spatial location of specific immune cells in liver and bone marrow are critical for understanding immune system programming. Considering the vital role immune function plays in offspring health, it will be important to understand how maternal diets can control developmental programming of innate and adaptive immunity.

Mitochondrial dysfunction and epigenetics underlying the link between early-life nutrition and non-alcoholic fatty liver disease

Early-life malnutrition plays a critical role in foetal development and predisposes to metabolic diseases later in life, according to the concept of 'developmental programming'. Different types of early nutritional imbalance, including undernutrition, overnutrition and micronutrient deficiency, have been related to long-term metabolic disorders. Accumulating evidence has demonstrated that disturbances in nutrition during the period of preconception, pregnancy and primary infancy can affect mitochondrial function and epigenetic mechanisms. Moreover, even though multiple mechanisms underlying non-alcoholic fatty liver disease (NAFLD) have been described, in the past years, special attention has been given to mitochondrial dysfunction and epigenetic alterations. Mitochondria play a key role in cellular metabolic functions. Dysfunctional mitochondria contribute to oxidative stress, insulin resistance and inflammation. Epigenetic mechanisms have been related to alterations in genes involved in lipid metabolism, fibrogenesis, inflammation and tumorigenesis. In accordance, studies have reported that mitochondrial dysfunction and epigenetics linked to early-life nutrition can be important contributing factors in the pathogenesis of NAFLD. In this review, we summarise the current understanding of the interplay between mitochondrial dysfunction, epigenetics and nutrition during early life, which is relevant to developmental programming of NAFLD.

Prevalence of incidental sonographic findings of hepatic steatosis in children under 4 years of age

BACKGROUND

The age of onset of nonalcoholic fatty liver disease (NAFLD) and its prevalence in young children is incompletely understood.

OBJECTIVE

We sought to evaluate the prevalence of ultrasound findings of hepatic steatosis in a cohort of children less than 4 years of age.

MATERIALS AND METHODS

This is an institutional review board-approved retrospective review of ultrasounds performed on children less than 4 years of age from January 2022 to August 2022 at a single quaternary care center. Two independent blinded reviewers evaluated for qualitative and semi-quantitative findings of hepatic steatosis. Per prior literature, hepatorenal index (HRI)>1.75 was used as a threshold suggestive of hepatic steatosis. Chi-square, Mann-Whitney U test, and logistic regression analyses were performed for univariable and multivariable statistical analyses. Kappa statistics were used to assess agreement between reviewers.

RESULTS

Eighty-five males and 102 females, median age of 1.1 years (interquartile range 2.1 years), were included. Qualitative findings of hepatic steatosis were seen in 26/187 (14%; 95% CI 10-20%). An HRI>1.75 was present in 15/187 (8%; 95% CI: 5-13%) of examinations, including 11 females and 4 males, and 7/123 (6%) participants <2 years old. Among participants with overweight or obesity, 8/43 (19%) had HRI>1.75 vs. 7/144 (5%) participants without overweight or obesity (P=0.004). Each percentile increase in anthropometrics percentile (weight-to-length or BMI, depending on age) was associated with 22 increased odds of HRI>1.75 (P=0.02).

CONCLUSION

Prevalence of sonographic findings of hepatic steatosis in an unselected sample of preschool-age children is 8-14%, and are more common in participants with overweight/obesity.

NREP contributes to development of NAFLD by regulating one-carbon metabolism in primary human hepatocytes

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease. We recently discovered that neuronal regeneration-related protein (NREP/P311), an epigenetically regulated gene reprogrammed by parental metabolic syndrome, is downregulated in human NAFLD. To investigate the impact of NREP insufficiency, we used RNA-sequencing, lipidomics, and antibody microarrays on primary human hepatocytes. NREP knockdown induced transcriptomic remodeling that overlapped with key pathways impacted in human steatosis and steatohepatitis. Additionally, we observed enrichment of pathways involving phosphatidylinositol signaling and one-carbon metabolism. Lipidomics analyses also revealed an increase in cholesterol esters and triglycerides and decreased phosphatidylcholine levels in NREP-deficient hepatocytes. Signalomics identified calcium signaling as a potential mediator of NREP insufficiency's effects. Our results, together with the encouraging observation that several single nucleotide polymorphisms (SNPs) spanning the NREP locus are associated with metabolic traits, provide a strong rationale for targeting hepatic NREP to improve NAFLD pathophysiology.

High-fat diet reveals the impact of Sar1b defects on lipid and lipoprotein profile and cholesterol metabolism

Biallelic pathogenic variants of the Sar1b gene cause chylomicron retention disease (CRD) whose central phenotype is the inability to secrete chylomicrons. Patients with CRD experience numerous clinical symptoms such as gastrointestinal, hepatic, neuromuscular, ophthalmic, and cardiological abnormalities. Recently, the production of mice expressing either a targeted deletion or mutation of Sar1b recapitulated biochemical and gastrointestinal defects associated with CRD. The present study was conducted to better understand little-known aspects of Sar1b mutations, including mouse embryonic development, lipid profile, and lipoprotein composition in response to high-fat diet, gut and liver cholesterol metabolism, sex-specific effects, and genotype-phenotype differences. Sar1b deletion and mutation produce a lethal phenotype in homozygous mice, which display intestinal lipid accumulation without any gross morphological abnormalities. On high-fat diet, mutant mice exhibit more marked abnormalities in body composition, adipose tissue and liver weight, plasma cholesterol, non-HDL cholesterol and polyunsaturated fatty acids than those on the regular Chow diet. Divergences were also noted in lipoprotein lipid composition, lipid ratios (serving as indices of particle size) and lipoprotein-apolipoprotein distribution. Sar1b defects significantly reduce gut cholesterol accumulation while altering key players in cholesterol metabolism. Noteworthy, variations were observed between males and females, and between Sar1b deletion and mutation phenotypes. Overall, mutant animal findings reveal the importance of Sar1b in several biochemical, metabolic and developmental processes.

Prenatal High-Fat Diet Combined with Microplastic Exposure Induces Liver Injury via Oxidative Stress in Male Pups

Prenatal high-fat diet (HFD) or exposure to microplastics can affect the accumulation of liver fat in offspring. We sought to determine the effects of maternal HFD intake and microplastic exposure on fatty liver injury through oxidative stress in pups. Pregnant female Sprague-Dawley rats were randomly divided into maternal HFD (experimental group) or normal control diet (NCD; control group) groups with or without microplastic exposure. As a result, the following groups were established: HFD-L (HFD + microplastics, 5 µm, 100 μg/L), HFD-H (HFD + microplastics, 5 µm, 1000 μg/L), NCD-L (NCD + microplastics, 5 µm, 100 μg/L), and NCD-H (NCD + microplastics, 5 µm, 1000 μg/L). The pups were sacrificed on postnatal day 7 (PD7). Liver histology revealed increased hepatic lipid accumulation in pups in the HFD-L and HFD-H groups compared to those in the HFD, NCD-L, NCD-H, and NCD groups on PD7. Similarly, liver TUNEL staining and cellular apoptosis were found to increase in pups in the HFD-L and HFD-H groups compared to those in the HFD, NCD-L, NCD-H, and NCD groups. The expression levels of malondialdehyde, a lipid peroxidation marker, were high in the HFD, HFD-L, and HFD-H groups; however, the highest expression was observed in the HFD-H group (p < 0.05). The levels of glutathione peroxidase, an antioxidant enzyme, decreased in the HFD, HFD-L, and HFD-H groups (p < 0.05). Overall, oxidative stress with cellular apoptosis plays a vital role in liver injury in offspring after maternal intake of HFD and exposure to microplastic; such findings may shed light on future therapeutic strategies.

Maternal Obesity Programs the Premature Aging of Rat Offspring Liver Mitochondrial Electron Transport Chain Genes in a Sex-Dependent Manner

We investigated whether maternal obesity affects the hepatic mitochondrial electron transport chain (ETC), sirtuins, and antioxidant enzymes in young (110 postnatal days (PND)) and old (650PND) male and female offspring in a sex- and age-related manner. Female Wistar rats ate a control (C) or high-fat (MO) diet from weaning, through pregnancy and lactation. After weaning, the offspring ate the C diet and were euthanized at 110 and 650PND. The livers were collected for RNA-seq and immunohistochemistry. Male offspring livers had more differentially expressed genes (DEGs) down-regulated by both MO and natural aging than females. C-650PND vs. C-110PND and MO-110PND vs. C-110PND comparisons revealed 1477 DEGs in common for males (premature aging by MO) and 35 DEGs for females. Analysis to identify KEGG pathways enriched from genes in common showed changes in 511 and 3 KEGG pathways in the male and female livers, respectively. Mitochondrial function pathways showed ETC-related gene down-regulation. All ETC complexes, sirtuin2, sirtuin3, sod-1, and catalase, exhibited gene down-regulation and decreased protein expression at young and old ages in MO males vs. C males; meanwhile, MO females down-regulated only at 650PND. Conclusions: MO accelerates the age-associated down-regulation of ETC pathway gene expression in male offspring livers, thereby causing sex-dependent oxidative stress, premature aging, and metabolic dysfunction.

Maternal diet alters long-term innate immune cell memory in fetal and juvenile hematopoietic stem and progenitor cells in nonhuman primate offspring

Maternal overnutrition increases inflammatory and metabolic disease risk in postnatal offspring. This constitutes a major public health concern due to increasing prevalence of these diseases, yet mechanisms remain unclear. Here, using nonhuman primate models, we show that maternal Western-style diet (mWSD) exposure is associated with persistent pro-inflammatory phenotypes at the transcriptional, metabolic, and functional levels in bone marrow-derived macrophages (BMDMs) from 3-year-old juvenile offspring and in hematopoietic stem and progenitor cells (HSPCs) from fetal and juvenile bone marrow and fetal liver. mWSD exposure is also associated with increased oleic acid in fetal and juvenile bone marrow and fetal liver. Assay for transposase-accessible chromatin with sequencing (ATAC-seq) profiling of HSPCs and BMDMs from mWSD-exposed juveniles supports a model in which HSPCs transmit pro-inflammatory memory to myeloid cells beginning in utero. These findings show that maternal diet alters long-term immune cell developmental programming in HSPCs with proposed consequences for chronic diseases featuring altered immune/inflammatory activation across the lifespan.

TASL Practice Guidance on the Clinical Assessment and Management of Patients with Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is a multisystem disease and is significantly associated with obesity, insulin resistance, type 2 diabetes mellitus, metabolic syndrome, and cardiovascular disease. NAFLD has become the most prevalent chronic liver disease in Western countries, and the proportion of NAFLD-related cirrhosis among patients on liver transplantation waiting lists has increased. In light of the accumulated data about NAFLD, and to provide a common approach with multi-disciplines dealing with the subject, it has become necessary to create new guidance for diagnosing and treating NAFLD. This guidance was prepared following an interdisciplinary study under the leadership of the Turkish Association for the Study of the Liver (TASL), Fatty Liver Special Interest Group. This new TASL Guidance is a practical application guide on NAFLD and was prepared to standardize the clinical approach to diagnosing and treating NAFLD patients. This guidance reflects many advances in the field of NAFLD. The proposals in this guidance are meant to aid decision-making in clinical practice. The guidance is primarily intended for gastroenterology, endocrinology, metabolism diseases, cardiology, internal medicine, pediatric specialists, and family medicine specialists.

Diabetes during Pregnancy: A Transgenerational Challenge

For many years, gestational diabetes mellitus (GDM) has been defined as “a glucose intolerance of variable magnitude that begins or is first diagnosed in pregnancy” and that, in most cases, resolves after delivery [...]

Transcriptional pathways linked to fetal and maternal hepatic dysfunction caused by gestational exposure to perfluorooctanoic acid (PFOA) or hexafluoropropylene oxide-dimer acid (HFPO-DA or GenX) in CD-1 mice

Per- and polyfluoroalkyl substances (PFAS) comprise a diverse class of chemicals used in industrial processes, consumer products, and fire-fighting foams which have become environmental pollutants of concern due to their persistence, ubiquity, and associations with adverse human health outcomes, including in pregnant persons and their offspring. Multiple PFAS are associated with adverse liver outcomes in adult humans and toxicological models, but effects on the developing liver are not fully described. Here we performed transcriptomic analyses in the mouse to investigate the molecular mechanisms of hepatic toxicity in the dam and its fetus after exposure to two different PFAS, perfluorooctanoic acid (PFOA) and its replacement, hexafluoropropylene oxide-dimer acid (HFPO-DA, known as GenX). Pregnant CD-1 mice were exposed via oral gavage from embryonic day (E) 1.5-17.5 to PFOA (0, 1, or 5 mg/kg-d) or GenX (0, 2, or 10 mg/kg-d). Maternal and fetal liver RNA was isolated (N = 5 per dose/group) and the transcriptome analyzed by Affymetrix Array. Differentially expressed genes (DEG) and differentially enriched pathways (DEP) were obtained. DEG patterns were similar in maternal liver for 5 mg/kg PFOA, 2 mg/kg GenX, and 10 mg/kg GenX (R2: 0.46-0.66). DEG patterns were similar across all 4 dose groups in fetal liver (R2: 0.59-0.81). There were more DEGs in fetal liver compared to maternal liver at the low doses for both PFOA (fetal = 69, maternal = 8) and GenX (fetal = 154, maternal = 93). Upregulated DEPs identified across all groups included Fatty Acid Metabolism, Peroxisome, Oxidative Phosphorylation, Adipogenesis, and Bile Acid Metabolism. Transcriptome-phenotype correlation analyses demonstrated > 1000 maternal liver DEGs were significantly correlated with maternal relative liver weight (R2 >0.92). These findings show shared biological pathways of liver toxicity for PFOA and GenX in maternal and fetal livers in CD-1 mice. The limited overlap in specific DEGs between the dam and fetus suggests the developing liver responds differently than the adult liver to these chemical stressors. This work helps define mechanisms of hepatic toxicity of two structurally unique PFAS and may help predict latent consequences of developmental exposure.

Zac1 and the Imprinted Gene Network program juvenile NAFLD in response to maternal metabolic syndrome

BACKGROUND AND AIMS

Within the next decade, NAFLD is predicted to become the most prevalent cause of childhood liver failure in developed countries. Predisposition to juvenile NAFLD can be programmed during early life in response to maternal metabolic syndrome (MetS), but the underlying mechanisms are poorly understood. We hypothesized that imprinted genes, defined by expression from a single parental allele, play a key role in maternal MetS-induced NAFLD, due to their susceptibility to environmental stressors and their functions in liver homeostasis. We aimed to test this hypothesis and determine the critical periods of susceptibility to maternal MetS.

APPROACH AND RESULTS

We established a mouse model to compare the effects of MetS during prenatal and postnatal development on NAFLD. Postnatal but not prenatal MetS exposure is associated with histological, biochemical, and molecular signatures of hepatic steatosis and fibrosis in juvenile mice. Using RNA sequencing, we show that the Imprinted Gene Network (IGN), including its regulator Zac1, is up-regulated and overrepresented among differentially expressed genes, consistent with a role in maternal MetS-induced NAFLD. In support of this, activation of the IGN in cultured hepatoma cells by overexpressing Zac1 is sufficient to induce signatures of profibrogenic transformation. Using chromatin immunoprecipitation, we demonstrate that Zac1 binds the TGF-β1 and COL6A2 promoters, forming a direct pathway between imprinted genes and well-characterized pathophysiological mechanisms of NAFLD. Finally, we show that hepatocyte-specific overexpression of Zac1 is sufficient to drive fibrosis in vivo.

CONCLUSIONS

Our findings identify a pathway linking maternal MetS exposure during postnatal development to the programming of juvenile NAFLD, and provide support for the hypothesis that imprinted genes play a central role in metabolic disease programming.

Insulin increases placental triglyceride as a potential mechanism for fetal adiposity in maternal obesity

OBJECTIVE

Maternal obesity increases the incidence of excess adiposity in newborns, resulting in lifelong diabetes risk. Elevated intrauterine fetal adiposity has been attributed to maternal hyperglycemia; however, this hypothesis does not account for the increased adiposity seen in newborns of mothers with obesity who have euglycemia. We aimed to explore the placental response to maternal hyperinsulinemia and the effect of insulin-like growth factor 2 (IGF-2) in promoting fetal adiposity by increasing storage and availability of nutrients to the fetus.

METHODS

We used placental villous explants and isolated trophoblasts from normal weight and obese women to assess the effect of insulin and IGF-2 on triglyceride content and insulin receptor signaling. Stable isotope tracer methods were used ex vivo to determine effect of hormone treatment on de novo lipogenesis (DNL), fatty acid uptake, fatty acid oxidation, and esterification in the placenta.

RESULTS

Here we show that placentae from euglycemic women with normal weight and obesity both have abundant insulin receptor. Placental depth and triglyceride were greater in women with obesity compared with normal weight women. In syncytialized placental trophoblasts and villous explants, insulin and IGF-2 activate insulin receptor, induce expression of lipogenic transcription factor SREBP-1 (sterol regulatory element-binding protein 1), and stimulate triglyceride accumulation. We demonstrate elevated triglyceride is attributable to increased esterification of fatty acids, without contribution from DNL and without an acceleration of fatty acid uptake.

CONCLUSIONS

Our work reveals that obesity-driven aberrations in maternal metabolism, such as hyperinsulinemia, alter placental metabolism in euglycemic conditions, and may explain the higher prevalence of excess adiposity in the newborns of obese women.

Effects of Maternal Gut Microbiota-Targeted Therapy on the Programming of Nonalcoholic Fatty Liver Disease in Dams and Fetuses, Related to a Prenatal High-Fat Diet

Metabolic disorders can start in utero. Maternal transmission of metabolic phenotypes may increase the risks of adverse metabolic outcomes, such as nonalcoholic fatty liver disease (NAFLD); effective intervention is essential to prevent this. The gut microbiome plays a crucial role in fat storage, energy metabolism, and NAFLD. We investigated the therapeutic use of probiotic Lactobacillus reuteri and postbiotic butyrate gestation in the prevention of perinatal high-fat diet-induced programmed hepatic steatosis in the offspring of pregnant Sprague–Dawley rats who received regular chow or a high-fat (HF) diet 8 weeks before mating. L. reuteri or sodium butyrate was administered via oral gavage to the gestated rats until their sacrifice on day 21 of gestation. Both treatments improved liver steatosis in pregnant dams; L. reuteri had a superior effect. L. reuteri ameliorated obesity and altered the metabolic profiles of obese gravid dams. Maternal L. reuteri therapy prevented maternal HF diet-induced fetal liver steatosis, and reformed placental remodeling and oxidative injury. Probiotic therapy can restore lipid dysmetabolism in the fetal liver, modulate nutrient-sensing molecules in the placenta, and mediate the short-chain fatty acid signaling cascade. The therapeutic effects of maternal L. reuteri on maternal NAFLD and NAFLD reprogramming in offspring should be validated for further clinical translation.

Butyrate ameliorates maternal high-fat diet-induced fetal liver cellular apoptosis

A maternal high-fat diet (HFD) can impact the offspring’s development of liver steatosis, with fetal development in utero being a crucial period. Therefore, this study investigated the mechanism and whether butyrate can rescue liver injury caused by maternal HFD in the fetus. Pregnant female Sprague Dawley rats were randomly divided into two groups, prenatal HFD (58% fat) exposure or normal control diet (4.5% fat). The HFD group was fed an HFD 7 weeks before mating and during gestation until sacrifice at gestation 21 days. After confirmation of mating, the other HFD group was supplemented with sodium butyrate (HFSB). The results showed that maternal liver histology showed lipid accumulation with steatosis and shortened ileum villi in HFD, which was ameliorated in the HFSB group (P<0.05). There was increased fetal liver and ileum TUNEL staining and IL-6 expression with increased fetal liver TNF-α and malondialdehyde expression in the HFD group (P<0.05), which decreased in the HFSB group (P<0.05). The fetal liver expression of phospho-AKT/AKT and GPX1 decreased in the HFD group but increased in the HFSB group (P<0.05). In conclusion that oxidative stress with inflammation and apoptosis plays a vital role after maternal HFD in the fetus liver that can be ameliorated with butyrate supplementation.

Altered Lipid Metabolism in Obese Women With Gestational Diabetes and Associations With Offspring Adiposity

CONTEXT

Gestational diabetes (GDM) affects 20 million women/year worldwide and is associated with childhood obesity. Infants of affected mothers have increased adiposity from birth, which leads to obesity in later life. However, it remains unknown whether the effect of GDM upon neonatal body composition is due to hyperglycemia alone or is mediated by other pathways.

OBJECTIVE

To investigate plasma lipid profiles in obese women according to GDM diagnosis, infant birthweight percentiles, and adiposity.

DESIGN

Prospective cohort from UPBEAT trial (ISRCTN 89971375).

SETTING

Hospital and community.

PATIENTS

867 obese pregnant women recruited in early pregnancy, assessed at 28 weeks for GDM. Offspring anthropometry was assessed at birth.

OUTCOME (PRESPECIFIED)

Neonatal birth percentile and abdominal circumference.

METHODS

Lipidomic profiling in the fasting plasma oral glucose tolerance test sample using direct infusion mass spectrometry. Analysis included logistic/linear regression, unadjusted and adjusted for maternal age, body mass index, parity, ethnicity, UPBEAT trial arm, and fetal sex. The limit of significance was P = 0.05 for offspring anthropometry and P = 0.002 for lipidomic data.

RESULTS

GDM in obese women was associated with elevated plasma concentrations of specific diglycerides [DG(32:0)] and triglycerides [TG(48:0), (50:1), (50:2)] containing fatty acids (16:0), (16:1), (18:0), and (18:1), consistent with increased de novo lipogenesis. In the whole cohort, these species were associated with birthweight percentile and neonatal abdominal circumference. Effects upon infant abdominal circumference remained significant after adjustment for maternal glycemia.

CONCLUSIONS

Increased de novo lipogenesis-related species in pregnant women with obesity and GDM are associated with measures of offspring adiposity and may be a target for improving lifelong health.

Maternal Pyrroloquinoline Quinone Supplementation Improves Offspring Liver Bioactive Lipid Profiles throughout the Lifespan and Protects against the Development of Adult NAFLD

Maternal obesity and consumption of a high-fat diet significantly elevate risk for pediatric nonalcoholic fatty liver disease (NAFLD), affecting 10% of children in the US. Almost half of these children are diagnosed with nonalcoholic steatohepatitis (NASH), a leading etiology for liver transplant. Animal models show that signs of liver injury and perturbed lipid metabolism associated with NAFLD begin in utero; however, safe dietary therapeutics to blunt developmental programming of NAFLD are unavailable. Using a mouse model of maternal Western-style diet (WD), we previously showed that pyrroloquinoline quinone (PQQ), a potent dietary antioxidant, protected offspring of WD-fed dams from development of NAFLD and NASH. Here, we used untargeted mass spectrometry-based lipidomics to delineate lipotoxic effects of WD on offspring liver and identify lipid targets of PQQ. PQQ exposure during pregnancy altered hepatic lipid profiles of WD-exposed offspring, upregulating peroxisome proliferator-activated receptor (PPAR) α signaling and mitochondrial fatty acid oxidation to markedly attenuate triglyceride accumulation beginning in utero. Surprisingly, the abundance of very long-chain ceramides, important in promoting gut barrier and hepatic function, was significantly elevated in PQQ-treated offspring. PQQ exposure reduced the hepatic phosphatidylcholine/phosphatidylethanolamine (PC/PE) ratio in WD-fed offspring and improved glucose tolerance. Notably, levels of protective n - 3 polyunsaturated fatty acids (PUFAs) were elevated in offspring exposed to PQQ, beginning in utero, and the increase in n - 3 PUFAs persisted into adulthood. Our findings suggest that PQQ supplementation during gestation and lactation augments pathways involved in the biosynthesis of long-chain fatty acids and plays a unique role in modifying specific bioactive lipid species critical for protection against NAFLD risk in later life.

Liver Steatosis: A Marker of Metabolic Risk in Children

Obesity is one of the greatest health challenges affecting children of all ages and ethnicities. Almost 19% of children and adolescents worldwide are overweight or obese, with an upward trend in the last decades. These reports imply an increased risk of fat accumulation in hepatic cells leading to a series of histological hepatic damages gathered under the acronym NAFLD (Non-Alcoholic Fatty Liver Disease). Due to the complex dynamics underlying this condition, it has been recently renamed as 'Metabolic Dysfunction Associated Fatty Liver Disease (MAFLD)', supporting the hypothesis that hepatic steatosis is a key component of the large group of clinical and laboratory abnormalities of Metabolic Syndrome (MetS). This review aims to share the latest scientific knowledge on MAFLD in children in an attempt to offer novel insights into the complex dynamics underlying this condition, focusing on the novel molecular aspects. Although there is still no treatment with a proven efficacy for this condition, starting from the molecular basis of the disease, MAFLD's therapeutic landscape is rapidly expanding, and different medications seem to act as modifiers of liver steatosis, inflammation, and fibrosis.

The Origins of NAFLD: The Potential Implication of Intrauterine Life and Early Postnatal Period

Fetal life and the first few months after birth represent a plastic age, defined as a “window of opportunity”, as the organism is particularly susceptible to environmental pressures and has to adapt to environmental conditions. Several perturbations in pregnancy, such as excessive weight gain, obesity, gestational diabetes mellitus and an inadequate or high-fat diet, have been associated with long-term metabolic consequences in offspring, even without affecting birth weight. Moreover, great interest has also been focused on the relationship between the gut microbiome of early infants and health status in later life. Consistently, in various epidemiological studies, a condition of dysbiosis has been associated with an increased inflammatory response and metabolic alterations in the host, with important consequences on the intestinal and systemic health of the unborn child. This review aims to summarize the current knowledge on the origins of NAFLD, with particular attention to the potential implications of intrauterine life and the early postnatal period. Due to the well-known association between gut microbiota and the risk of NAFLD, a specific focus will be devoted to factors affecting early microbiota formation/composition.

Gestational exposure to high fat diets and bisphenol A alters metabolic outcomes in dams and offspring, but produces hepatic steatosis only in dams

The prevalence of non-alcoholic fatty liver disease (NAFLD) is increasing worldwide. Perinatal development is a critical window for altered, lifelong health trajectory, and evidence supports the role of perinatal programming in chronic metabolic diseases. To examine the impact of diet and bisphenol A (BPA) on the developmental trajectory of NAFLD in offspring, we exposed dams from pre-gestation through lactation to a human-relevant dose of oral BPA coupled with intake of high fat Western or Mediterranean-style diets. We assessed hepatic steatosis by quantifying hepatic triglycerides (TGs) and metabolic health by measuring body weight, relative organ weights, and serum hormone levels in dams and offspring at postnatal day 10 (PND10) and 10-months of age. In dams, consumption of the Western or Mediterranean diet increased hepatic TGs 1.7-2.4-fold, independent of BPA intake. Among offspring, both perinatal diet and BPA exposure had a greater impact on metabolic outcomes than on hepatic steatosis. At PND10, serum leptin levels were elevated 2.6-4.8-fold in pups exposed to the Mediterranean diet, with a trend for sex-specific effects on body and organ weights. At 10-months, sex-specific increases in organ weight and hormone levels were observed in mice perinatally exposed to Western + BPA or Mediterranean + BPA. These findings suggest lifestage-specific interaction of perinatal exposures to experimental diets and BPA on offspring metabolic health without effects on NAFLD later in life. Importantly, alterations in dam phenotype by diet and BPA exposure appear to impact offspring health trajectory, emphasizing the need to define dam diet in assessing effects of environmental exposures on offspring health.

Factors That Predict the Progression of Non-alcoholic Fatty Liver Disease (NAFLD)

Non-alcoholic fatty liver disease (NAFLD) refers to a spectrum of diseases involving the deposition of fat in the hepatocytes of people with little to no alcohol consumption. NAFLD is associated with hypertension, diabetes, obesity, etc. As their prevalence increases, the propensity and severity of NAFLD might increase. As per the recently developed multi-hit hypothesis, factors like oxidative stress, genetic predisposition, lipotoxicity, and insulin resistance have been found to play a key role in the development of NAFLD and its associated complications. This article focuses on NAFLD, its pathophysiology, risk factors, and the various genetic and epigenetic factors involved in its development along with possible treatment modalities.

We conducted an all-language literature search on Medline, Cochrane, Embase, and Google Scholar until October 2021. The following search strings and Medical Subject Heading (MeSH) terms were used: “NAFLD,” “NASH,” “Fibrosis,” and “Insulin Resistance.” We explored the literature on NAFLD for its epidemiology, pathophysiology, the role of various genes, and how they influence the disease and associated complications about the disease and its hepatic and extrahepatic complications. With its rapidly increasing prevalence rates across the world and serious complications like NASH and hepatocellular carcinoma, NAFLD is becoming a major public health issue and more research is needed to formulate better screening tools and treatment protocols.

Longitudinal associations of total and trunk fat in childhood and adolescence and risk of hepatic steatosis at 24 years

BACKGROUND

The importance of body fat distribution in the development of nonalcoholic fatty liver disease (NAFLD) is unclear.

OBJECTIVE

To examine whether total and truncal fat deposition patterns in childhood/adolescence are associated with NAFLD risk at 24 years.

METHODS

Data were from 1657 participants in the Avon Longitudinal Study of Parents and Children. Transient elastography was used to assess hepatic steatosis (low/moderate/severe) at 24 years and dual-energy X-ray absorptiometry was used to assess total body fat percent (TBF%) and trunk fat percent (TrF%) at 9, 13, 15, 17, and/or 24 years. Linear mixed models were constructed with quadratic age to examine trajectories of TBF% and TrF% by steatosis at 24 years, adjusting for confounders.

RESULTS

In both sexes, TBF% trajectories from 9 to 24 years followed a similar pattern based on steatosis group (P = .83 for boys and P = .14 for girls for age² *steatosis fixed effect). However, at all ages TBF% was higher for moderate/severe vs low steatosis at 24 years (P < .05). In contrast, TrF% trajectories diverged based on steatosis group (P = .001 for boys and P = .0002 for girls for age² *steatosis fixed effect), such that, in both sexes, participants with moderate/severe steatosis at 24 yrs exhibited less decline in TrF% from adolescence to adulthood compared to participants with low steatosis at 24 yrs. Similar to TBF%, TrF% was higher at nearly all ages for moderate/severe vs low steatosis. Results were similar after adjusting for BMI category at each age, except in boys some differences for TrF% were attenuated.

CONCLUSIONS

These findings suggest that sex-specific body fat distribution patterns in childhood/adolescence may help to identify those at risk of developing NAFLD in adulthood.

Second-trimester maternal lipid profiles rather than glucose levels predict the occurrence of neonatal macrosomia regardless of glucose tolerance status: A matched cohort study in Beijing

AIMS

The mechanism underlying fetal overgrowth during pregnancy remains elusive. We aimed to establish a predictive model to identify the high-risk individuals with macrosomia in the second trimester of pregnancy.

DESIGN

A total of 2577 pregnant women with a routine 75-g oral glucose tolerance test during 24-28 gestational weeks were screened in a prospective cohort. Gestational diabetes mellitus (GDM) cases were 1:1 matching with age (±2 years) in normal glucose tolerance (NGT) ones from the same region. Multivariate logistic regression analysis and receiver operating characteristic (ROC) curve were performed to determine the index and its inflection point for predicting macrosomia occurrence.

RESULTS

The data of perinatal outcomes of 565 GDM and 549 NGT who had given birth to single live babies at term were analyzed. Notably, we found serum apolipoprotein B (ApoB) level higher than 4.04 g/L combined with triglycerides (TG)/high-density lipoprotein cholesterol (HDLC) ratio above 1.36 formed the predictive model in both groups. The area under the ROC curve of this predictive model included ApoB and TG/HDL-C reached 0.807 (95% CI: 0.771-0.873) with a sensitivity of 71.9% and a specificity of 78.6%. Mediation analysis revealed that ApoB and TG/HDL-C ratio mediated the harmful effect of FBG on the risk of macrosomia.

CONCLUSION

Maternal ApoB levels and TG/HDL-C ratio could predict macrosomia occurrence in pregnancy, which might be a new target for early intervention to prevent excess fetal growth.

The Carbohydrate Threshold in Pregnancy and Gestational Diabetes: How Low Can We Go?

The original nutrition approach for the treatment of gestational diabetes mellitus (GDM) was to reduce total carbohydrate intake to 33-40% of total energy (EI) to decrease fetal overgrowth. Conversely, accumulating evidence suggests that higher carbohydrate intakes (60-70% EI, higher quality carbohydrates with low glycemic index/low added sugars) can control maternal glycemia. The Institute of Medicine (IOM) recommends ≥175 g/d of carbohydrate intake during pregnancy; however, many women are consuming lower carbohydrate (LC) diets (<175 g/d of carbohydrate or <40% of EI) within pregnancy and the periconceptual period aiming to improve glycemic control and pregnancy outcomes. This report systematically evaluates recent data (2018-2020) to identify the LC threshold in pregnancy in relation to safety considerations. Evidence from 11 reports suggests an optimal carbohydrate range of 47-70% EI supports normal fetal growth; higher than the conventionally recognized LC threshold. However, inadequate total maternal EI, which independently slows fetal growth was a frequent confounder across studies. Effects of a carbohydrate intake <175 g/d on maternal ketonemia and plasma triglyceride/free fatty acid concentrations remain unclear. A recent randomized controlled trial (RCT) suggests a higher risk for micronutrient deficiency with carbohydrate intake ≤165 g/d in GDM. Well-controlled prospective RCTs comparing LC (<165 g/d) and higher carbohydrate energy-balanced diets in pregnant women are clearly overdue.

Maternal high-fat diet disrupted one-carbon metabolism in offspring, contributing to nonalcoholic fatty liver disease

BACKGROUND & AIMS

Pregnant women may transmit their metabolic phenotypes to their offspring, enhancing the risk for nonalcoholic fatty liver disease (NAFLD); however, the molecular mechanisms remain unclear.

METHODS

Prior to pregnancy female mice were fed either a maternal normal-fat diet (NF-group, "no effectors"), or a maternal high-fat diet (HF-group, "persistent effectors"), or were transitioned from a HF to a NF diet before pregnancy (H9N-group, "effectors removal"), followed by pregnancy and lactation, and then offspring were fed high-fat diets after weaning. Offspring livers were analysed by functional studies, as well as next-generation sequencing for gene expression profiles and DNA methylation changes.

RESULTS

The HF, but not the H9N offspring, displayed glucose intolerance and hepatic steatosis. The HF offspring also displayed a disruption of lipid homeostasis associated with an altered methionine cycle and abnormal one-carbon metabolism that caused DNA hypermethylation and L-carnitine depletion associated with deactivated AMPK signalling and decreased expression of PPAR-α and genes for fatty acid oxidation. These changes were not present in H9N offspring. In addition, we identified maternal HF diet-induced genes involved in one-carbon metabolism that were associated with DNA methylation modifications in HF offspring. Importantly, the DNA methylation modifications and their associated gene expression changes were reversed in H9N offspring livers.

CONCLUSIONS

Our results demonstrate for the first time that maternal HF diet disrupted the methionine cycle and one-carbon metabolism in offspring livers which further altered lipid homeostasis. CpG islands of specific genes involved in one-carbon metabolism modified by different maternal diets were identified.

Liver Proteome Profile of Growth Restricted and Appropriately Grown Newborn Wistar Rats Associated With Maternal Undernutrition

Background

Fetal growth restriction (FGR) has been associated with adverse perinatal outcomes and epigenetic modifications that impact gene expression leading to permanent changes of fetal metabolic pathways and thereby influence development of disease in childhood and adult life. In this study, we investigated the result of maternal food restriction on liver protein expression in Wistar male newborn pups.

Materials & Methods

Ten (n = 10) timed pregnant Wistar rats on their 14th day of gestation were randomly assigned to either control (n = 4) or food restricted group (n = 6). The control group had ad libitum access to food. In the food restricted group, maternal diet was limited in a moderate fashion (50%) from day 15 of pregnancy until delivery. All rats delivered spontaneously on day 21 and newborn pups were immediately weighed. Pups born to normally nourished mothers were considered as controls, while pups born to food restricted mothers were subdivided into two groups, based on their birth weight: growth restricted (FGR) and appropriately grown (non-FGR). Rats were euthanized immediately after birth and liver tissues of 11 randomly selected male offspring (FGR n = 4, non-FGR n = 4, control n = 3) were collected and analyzed using quantitative proteomics.

Results

In total 6,665 proteins were profiled. Of these, 451 and 751 were differentially expressed in FGR and non-FGR vs. control, respectively, whereas 229 proteins were commonly expressed. Bioinformatics analysis of the differentially expressed proteins (DEPs) in FGR vs. control revealed induction of the super-pathway of cholesterol biosynthesis and inhibition of thyroid hormone metabolism, fatty acid beta oxidation and apelin liver signaling pathway. Analysis of DEPs in non-FGR vs. control groups showed inhibition of thyroid hormone metabolism, fatty acid beta oxidation, and apelin liver signaling pathway.

Conclusion

This study demonstrates the impact of prenatal food restriction on the proteomic liver profile of FGR and non-FGR offspring underlying the importance of both prenatal adversities and birth weight on liver-dependent postnatal disease.

Açaí (Euterpe oleracea Martius) supplementation improves oxidative stress biomarkers in liver tissue of dams fed a high-fat diet and increases antioxidant enzymes' gene expression in offspring

Lipids excess from an uterine environment can increase free radicals production of and thus induce oxidative status imbalance, a key factor for progression of non-alcoholic fatty liver disease (NAFLD) in offspring. Food antioxidant components in maternal diet may play an important role in preventing offspring metabolic disorders. The objective of the study was to evaluate the effects of açaí pulp supplementation on maternal high-fat diet, by assessing activity and expression of antioxidant enzymes and biomarkers of oxidative stress in the liver. Female Fisher rats were divided into four groups and fed a control diet (C), a high-fat diet (HF), a control diet supplemented with açaí (CA) and a high-fat diet supplemented with açaí (HFA) before mating, during gestation and lactation. The effects of açaí supplementation on oxidative stress biomarkers and antioxidant enzymes expression were evaluated in dams and male offspring after weaning. HFA diet increased body weight in dams, however reduced absolute and relative liver weight. There was a reduction in liver biomarkers of oxidative stress, malondialdehyde and carbonyl protein, as well as in catalase, glutathione peroxidase and superoxide dismutase activity. In offspring, HFA diet reduced liver weight and increased Gpx1, Gpx4 and Sod1 mRNA expression. These results suggest that açaí is able to restore redox status, preventing oxidative damage in dams by a direct mechanism and to promote beneficial effects on expression of antioxidant defences related genes in offspring.

Gestational Diabetes Mellitus and Infant Adiposity at Birth: A Systematic Review and Meta-Analysis of Therapeutic Interventions

Exposure to untreated gestational diabetes mellitus (GDM) in utero increases the risk of obesity and type 2 diabetes in adulthood, and increased adiposity in GDM-exposed infants is suggested as a plausible mediator of this increased risk of later-life metabolic disorders. Evidence is equivocal regarding the impact of good glycaemic control in GDM mothers on infant adiposity at birth. We systematically reviewed studies reporting fat mass (FM), percent fat mass (%FM) and skinfold thicknesses (SFT) at birth in infants of mothers with GDM controlled with therapeutic interventions (IGDMtr). While treating GDM lowered FM in newborns compared to no treatment, there was no difference in FM and SFT according to the type of treatment (insulin, metformin, glyburide). IGDMtr had higher overall adiposity (mean difference, 95% confidence interval) measured with FM (68.46 g, 29.91 to 107.01) and %FM (1.98%, 0.54 to 3.42) but similar subcutaneous adiposity measured with SFT, compared to infants exposed to normal glucose tolerance (INGT). This suggests that IGDMtr may be characterised by excess fat accrual in internal adipose tissue. Given that intra-abdominal adiposity is a major risk factor for metabolic disorders, future studies should distinguish adipose tissue distribution of IGDMtr and INGT.

Murine neonatal ketogenesis preserves mitochondrial energetics by preventing protein hyperacetylation

Ketone bodies are generated in the liver and allow for the maintenance of systemic caloric and energy homeostasis during fasting and caloric restriction. It has previously been demonstrated that neonatal ketogenesis is activated independently of starvation. However, the role of ketogenesis during the perinatal period remains unclear. Here, we show that neonatal ketogenesis plays a protective role in mitochondrial function. We generated a mouse model of insufficient ketogenesis by disrupting the rate-limiting hydroxymethylglutaryl-CoA synthase 2 enzyme gene (Hmgcs2). Hmgcs2 knockout (KO) neonates develop microvesicular steatosis within a few days of birth. Electron microscopic analysis and metabolite profiling indicate a restricted energy production capacity and accumulation of acetyl-CoA in Hmgcs2 KO mice. Furthermore, acetylome analysis of Hmgcs2 KO cells revealed enhanced acetylation of mitochondrial proteins. These findings suggest that neonatal ketogenesis protects the energy-producing capacity of mitochondria by preventing the hyperacetylation of mitochondrial proteins.

Developmental effects of in utero metformin exposure

According to the Developmental Origins of Health and Disease (DOHaD) hypothesis, the intrauterine environment influences fetal programming and development, affecting offspring disease susceptibility in adulthood. In recent years, therapeutic use of the Type 2 diabetes drug metformin has expanded to the treatment of pre-diabetes, polycystic ovarian syndrome, and gestational diabetes. Because metformin both undergoes renal excretion and binds to receptors on the placenta, the fetus receives equivalent maternal dosing. Although no teratogenic nor short-term harmful fetal impact of metformin is known to occur, the effects of metformin exposure on longer-range offspring development have not yet been fully elucidated. This review encapsulates the (albeit limited) existing knowledge regarding the potential longer-term impact of intrauterine metformin exposure on the development of key organs including the liver, central nervous system, heart, gut, and endocrine pancreas in animal models and humans. We discuss molecular and cellular mechanisms that would be altered in response to treatment and describe the potential consequences of these developmental changes on postnatal health. Further studies regarding the influence of metformin exposure on fetal programming and adult metabolic health will provide necessary insight to its long-term risks, benefits, and limitations in order to guide decisions for use of metformin during pregnancy.

Possible Hepatoprotective Effect of Tocotrienol-Rich Fraction Vitamin E in Non-alcoholic Fatty Liver Disease in Obese Children and Adolescents

Obesity has become a worldwide health concern among the pediatric population. The prevalence of non-alcoholic fatty liver disease (NAFLD) is growing rapidly, alongside the high prevalence of obesity. NAFLD refers to a multifactorial disorder that includes simple steatosis to non-alcoholic steatohepatitis (NASH) with or devoid of fibrosis. NAFLD is regarded as a systemic disorder that influences glucose, lipid, and energy metabolism with hepatic manifestations. A sedentary lifestyle and poor choice of food remain the major contributors to the disease. Prompt and timely diagnosis of NAFLD among overweight children is crucial to prevent the progression of the condition. Yet, there has been no approved pharmacological treatment for NAFLD in adults or children. As indicated by clinical evidence, lifestyle modification plays a vital role as a primary form of therapy for managing and treating NAFLD. Emphasis is on the significance of caloric restriction, particularly macronutrients (fats, carbohydrates, and proteins) in altering the disease consequences. A growing number of studies are now focusing on establishing a link between vitamins and NAFLD. Different types of vitamin supplements have been shown to be effective in treating NAFLD. In this review, we elaborate on the potential role of vitamin E with a high content of tocotrienol as a therapeutic alternative in treating NAFLD in obese children.

Effect of Probiotic Supplementation on Newborn Birth Weight for Mother with Gestational Diabetes Mellitus or Overweight/Obesity: A Systematic Review and Meta-Analysis

High birth weight indicates the future risk of obesity and increased fat mass in childhood. Maternal gestational diabetes mellitus (GDM) or overweight are powerful predictors of high birth weight. Studies on probiotic supplementation during pregnancy have reported its benefits in modulating gut microbiota composition and improving glucose and lipid metabolism in pregnant women. Therefore, probiotic intervention during pregnancy was proposed to interrupt the transmission of obesity from mothers to newborns. Thus, we performed a meta-analysis to investigate the effect of probiotic intervention in pregnant women with GDM or overweight on newborn birth weight. We searched PubMed, EMBASE, Cochrane Library, and Web of Science databases up to 18 December 2019. Randomized controlled trials (RCTs) comparing pregnant women with GDM or overweight who received probiotic intervention during pregnancy with those receiving placebo were eligible for the analysis. Newborn birth weights were pooled to calculate the mean difference with a 95% confidence interval (CI). Two reviewers assessed the trial quality and extracted data independently. Seven RCTs involving 1093 participants were included in the analysis. Compared with the placebo, probiotics had little effect on newborn birth weight of pregnant women with GDM or overweight (mean difference = -10.27, 95% CI = -90.17 to 69.63, p = 0.801). The subgroup analysis revealed that probiotic intake by women with GDM decreased newborn birth weight, whereas probiotic intake by obese pregnant women increased newborn birth weight. Thus, no evidence indicates that probiotic intake by pregnant women with GDM or overweight can control newborn birth weight.

Auranofin Attenuates Non-Alcoholic Fatty Liver Disease by Suppressing Lipid Accumulation and NLRP3 Inflammasome-Mediated Hepatic Inflammation In Vivo and In Vitro

Non-alcoholic fatty liver disease (NAFLD) causes liver dysfunction and is associated with obesity and type 2 diabetes. Chronic inflammation is associated not only with the development of NAFLD, but also with hepatic diseases, including steatohepatitis, cirrhosis, and hepatocellular carcinoma. Auranofin is a treatment for rheumatoid arthritis and has recently been reported to have potential effects against a variety of diseases, including inflammation, cancer, and viral infection. In this study, auranofin may be considered as a new treatment for the management of metabolic syndrome, as well as in the treatment of NAFLD through immunomodulation. To determine the effect of auranofin on NAFLD, C57BL/6 mice were randomly grouped, fed a regular diet or a high fat diet (HFD), and injected with normal saline or auranofin for 8 weeks. Auranofin significantly decreased the body weight, epididymal fat weight, serum aspartate aminotransferase (AST), and glucose, as well as the serum triglyceride, cholesterol, and low-density lipoprotein cholesterol levels as compared to the HFD group. We also observed that hepatic steatosis was increased in the HFD group and was suppressed by auranofin treatment. In addition, auranofin suppressed the expressions of interleukin (IL)-1β, IL-18, caspase-1, and the NOD-like receptor family pyrin domain containing 3 (NLRP3) in the liver tissue. Furthermore, the expression of NADPH oxidase 4 and peroxisome proliferator-activated receptor γ (PPARγ), which are a major source of oxidative stress and a regulator of adipogenesis, respectively, were also decreased by auranofin. In addition, primary mouse hepatocytes were incubated with lipopolysaccharide (LPS) and palmitic acid (PA) to induce lipid accumulation and hepatic inflammation for an in vitro model. Auranofin could significantly inhibit LPS- and PA-induced inflammatory activity including nitric oxide and NLRP3 inflammasome-mediated cytokines. The results of this study demonstrate that auranofin treatment inhibits the characteristics of NAFLD through the inhibition of NLRP3 inflammasome. Therefore, auranofin may have potential as a candidate for improving NAFLD symptoms.

Perspectives on youth-onset nonalcoholic fatty liver disease

BACKGROUND

The prevalence and incidence of youth-onset nonalcoholic fatty liver disease (NAFLD) far exceeds other paediatric chronic liver diseases and represents a considerable public health issue globally.

METHODS

Here, we performed a narrative review of current knowledge regarding the epidemiology of paediatric NAFLD, selected concepts in pathogenesis, comorbidities, diagnosis, and management, and issues related to the transition to adulthood.

RESULTS

Paediatric NAFLD has become increasingly more prevalent, especially in certain subgroups, such as children with obesity and certain races/ethnicities. The pathophysiology of paediatric NAFLD is complex and multifactorial, driven by an interaction of environmental and genetic factors. Once developed, NAFLD in childhood is associated with type 2 diabetes, hypertension, increased cardiovascular disease risk, and end-stage liver disease. This predicts an increased burden of morbidity and mortality in adolescents and young adults. Early screening and diagnosis are therefore crucial, and the development of noninvasive biomarkers remains an active area of investigation. Currently, treatment strategies are focused on lifestyle changes, but there is also research interest in pharmacological and surgical options. In the transition from paediatric to adult care, there are several potential challenges/barriers to treatment and research is needed to understand how best to support patients during this time.

CONCLUSIONS

Our understanding of the epidemiology and pathophysiology of paediatric NAFLD has increased considerably over recent decades, but several critical knowledge gaps remain and must be addressed in order to better mitigate the short-term and long-term risks of youth-onset NAFLD.

Differential Analysis of Serum Principal Components Treated with Compound Sophora Decoction and Related Compounds Based on High-Resolution Mass Spectrometry (HRMS)

OBJECTIVE

To compare the differences in the serum principal components in ulcerative colitis- (UC-) induced rats, treated with compound Sophora decoction, matrine, oxymatrine monomer mixture, and indirubin monomer, and to provide a modern scientific basis for elucidating the clinical efficacy of compound Sophora decoction for the treatment of UC.

METHODS

The serum samples of rats from each group were obtained after drug administration, and the serum principal components of each group were analyzed by high-resolution mass spectrometry. Agilent Eclipse XDB C18 chromatographic column (100 mm × 2.1 mm, 3.5 m) was used for separation. The mobile phase was water (A) and methanol (B) (0.1% formic acid) gradient elution, 0-3 min (B: 20%-40%), 3-10 min (B: 40%-54%), 10-25 min (B: 54%), 25-35 min (B: 54%-70%), 35-45 min (B: 70%-80%), 45-50 min (B: 80%), 50-60 min (B: 80%-100%), 70-72 min (B: 100%-20%), and 72-77 min (B: 20%); flow rate, 300 μL/min; column temperature, 40°C; and injection volume, 10 μL. ESI source was selected and scanned in the positive and negative ion modes. The scanning range was 70-1500 m/z; ion-source gas 1 (GS1): 55 psi; ion-source gas 2 (GS2): 60 psi; CUR: 30 psi; ion-source temperature (TEM): 550°C; ion-source voltage (ISVF) : 5500 V/-4500 V; decluster voltage (DP): 100 V; collision energy (CE): 35 V/-35 V; collision energy gain (CES) : 15 V/-15 V; and data acquisition mode: IDA. After the data from each group were imported into MarkView 1.3, the molecular weights and retention times of different substances were obtained and qualitatively analyzed by ChemSpider and PeakView 2.0.

RESULTS

In the negative ion mode, 26 differential compounds were identified in the compound Sophora decoction group (FFKST) compared to the model group (M), and 18 differential compounds were identified in the matrine and oxymatrine group (KST) compared to the model group (M). In the positive ion mode, 11 and 7 differential compounds were identified in the compound Sophora decoction group (FFKST) and the matrine and oxymatrine group (KST) compared to the model group (M), respectively. The responses of all compounds in each group were compared with each other. As the different principal component substances in the indirubin group (DYH) displayed little correlation with other groups, the different components in this group were not researched thoroughly.

CONCLUSION

By comparing the differences in the serum principal components from each administration group, we found that the FFKST group exhibited enhanced synthesis of the serum principal components; however, the compound doses of matrine and oxymatrine monomers did not exhibit the same changes in the serum principal components of UC-induced rats. Finally, the traditional Chinese medicine compound is more advantageous than monomers.

Lean maternal hyperglycemia alters offspring lipid metabolism and susceptibility to diet-induced obesity in mice†

We previously developed a model of gestational diabetes mellitus (GDM) in which dams exhibit glucose intolerance, insulin resistance, and reduced insulin response to glucose challenge only during pregnancy, without accompanying obesity. Here, we aimed to determine how lean gestational glucose intolerance affects offspring risk of metabolic dysfunction. One cohort of offspring was sacrificed at 19 weeks, and one at 31 weeks, with half of the second cohort placed on a high-fat, high-sucrose diet (HFHS) at 23 weeks. Exposure to maternal glucose intolerance increased weights of HFHS-fed offspring. Chow-fed offspring of GDM dams exhibited higher body fat percentages at 4, 12, and 20 weeks of age. At 28 weeks, offspring of GDM dams fed the HFHS but not the chow diet (CD) also had higher body fat percentages than offspring of controls (CON). Exposure to GDM increased the respiratory quotient (Vol CO2/Vol O2) in offspring. Maternal GDM increased adipose mRNA levels of peroxisome proliferator-activated receptor gamma (Pparg) and adiponectin (Adipoq) in 31-week-old CD-fed male offspring, and increased mRNA levels of insulin receptor (Insr) and lipoprotein lipase (Lpl) in 31-week-old male offspring on both diets. In liver at 31 weeks, mRNA levels of peroxisome proliferator-activated receptor alpha (Ppara) were elevated in CD-fed male offspring of GDM dams, and male offspring of GDM dams exhibited higher mRNA levels of Insr on both diets. Neither fasting insulin nor glucose tolerance was affected by exposure to GDM. Our findings show that GDM comprising glucose intolerance only during pregnancy programs increased adiposity in offspring, and suggests increased insulin sensitivity of subcutaneous adipose tissue.

The offspring from rats fed a fatty diet display impairments in the activation of liver peroxisome proliferator activated receptor alpha and features of fatty liver disease

Maternal obesity programs liver derangements similar to those of NAFLD. Our main goal was to evaluate whether these liver anomalies were related to aberrant PPARα function. Obesity was induced in female Albino-Wistar rats by a fatty diet (FD rats). Several parameters related to NAFLD were evaluated in both plasma and livers from fetuses of 21 days of gestation and 140-day-old offspring. FD fetuses and offspring developed increased levels of AST and ALT, signs of inflammation and oxidative and nitrative stress-related damage. FD offspring showed dysregulation of Plin2, CD36, Cyp4A, Aco, Cpt-1, Hadha and Acaa2 mRNA levels, genes involved in lipid metabolism and no catabolic effect of the PPARα agonist clofibrate. These results suggest that the FD offspring is prone to develop fatty liver, a susceptibility that can be linked to PPARα dysfunction, and that this could in turn be related to the liver impairments programmed by maternal obesity.

Liquid Biopsy for the Diagnosis of Viral Hepatitis, Fatty Liver Steatosis, and Alcoholic Liver Diseases

During the progression from hepatitis to fibrosis, cirrhosis, and liver failure, the accumulation of stressed/damaged hepatocyte elements associated with liver inflammation is critical. The causes of hepatocyte injuries include viral hepatitis infections, alcoholic hepatitis, and non-alcoholic fatty liver disease. Hepatocyte-derived extracellular vesicles (Hep-EVs) released from stressed/damaged hepatocytes are partly responsible for liver disease progression and liver damage because they activate non-parenchymal cells and infiltrate inflammatory cells within the liver, which are in turn are an important source of EVs. This cell-to-cell signaling is prevalent during inflammation in many liver diseases. Accordingly, special emphasis should be placed on liquid biopsy methods for the long-term monitoring of chronic liver diseases. In the present review, we have highlighted various aspects of current liquid biopsy research into chronic liver diseases. We have also reviewed recent progress on liquid biopsies that focus on cell-free DNA (cfDNA), long non-coding RNA (lncRNA), and the proteins in EVs as potential diagnostic tools and novel therapeutic targets in patients with viral hepatitis, fatty liver steatosis, and alcoholic liver diseases.

Nonalcoholic Fatty Liver Disease in Children: Unique Considerations and Challenges

Nonalcoholic fatty liver disease (NAFLD) is increasing in prevalence in concert with the global epidemic of obesity and is being diagnosed at increasingly younger ages. The unique histologic features and early presentation of disease in pediatrics suggest that children and adults may differ with regard to etiopathogenesis, with children displaying a greater vulnerability to genetic and environmental factors. Of significant relevance to pediatrics, in utero and perinatal stressors may alter the lifelong health trajectory of a child, increasing the risk of NAFLD and other cardiometabolic diseases. The development and progression of disease in childhood is likely to carry increased risk of long-term morbidity. Novel biomarkers and therapeutic agents are needed to avoid the otherwise inevitable health and societal consequences of this rapidly expanding pediatric population.

Parental metabolic syndrome epigenetically reprograms offspring hepatic lipid metabolism in mice

The prevalence of nonalcoholic fatty liver disease (NAFLD) is increasing worldwide. Although gene-environment interactions have been implicated in the etiology of several disorders, the impact of paternal and/or maternal metabolic syndrome on the clinical phenotypes of offspring and the underlying genetic and epigenetic contributors of NAFLD have not been fully explored. To this end, we used the liver-specific insulin receptor knockout (LIRKO) mouse, a unique nondietary model manifesting 3 hallmarks that confer high risk for the development of NAFLD: hyperglycemia, insulin resistance, and dyslipidemia. We report that parental metabolic syndrome epigenetically reprograms members of the TGF-β family, including neuronal regeneration-related protein (NREP) and growth differentiation factor 15 (GDF15). NREP and GDF15 modulate the expression of several genes involved in the regulation of hepatic lipid metabolism. In particular, NREP downregulation increases the protein abundance of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) and ATP-citrate lyase (ACLY) in a TGF-β receptor/PI3K/protein kinase B-dependent manner, to regulate hepatic acetyl-CoA and cholesterol synthesis. Reduced hepatic expression of NREP in patients with NAFLD and substantial correlations between low serum NREP levels and the presence of steatosis and nonalcoholic steatohepatitis highlight the clinical translational relevance of our findings in the context of recent preclinical trials implicating ACLY in NAFLD progression.

Overweight and obesity status from the prenatal period to adolescence and its association with non-alcoholic fatty liver disease in young adults: cohort study

OBJECTIVE

To examine the associations of maternal and child overweight status across multiple time-points with liver fat content in the offspring during young adulthood.

DESIGN

Cohort study.

SETTING

ELEMENT Cohort in Mexico City.

POPULATION

Pregnant women with singleton births (n = 97).

METHODS

We quantified hepatic triglyceride content (liver fat content) by proton magnetic resonance spectroscopy (1H MRS) and conventional T2-weighted MRIs (3T scanner) in 97 young adults from the ELEMENT birth cohort in Mexico City. Historical records of the cohort were used as a source of pregnancy, and childhood and adolescence anthropometric information, overweight and obesity (OWOB) were defined. Adjusted structural equation models were run to identify the association between OWOB in different life stages with liver fat content (log-transformed) in young adulthood.

MAIN OUTCOME

Maternal OWOB at the time of delivery was directly and indirectly associated with the liver fat content in the offspring at young adulthood.

RESULTS

Seventeen percent of the participants were classified as having NAFLD. We found a strong association of OWOB between all periods assessed. Maternal OWOB at time of delivery (β = 1.97, 95% CI 1.28-3.05), and OWOB status in the offspring at young adulthood (β = 3.17, 95% CI 2.10-4.77) were directly associated with the liver fat content in the offspring. Also, maternal OWOB was indirectly associated with liver fat content through offspring OWOB status.

CONCLUSION

We found that maternal OWOB status is related to fatty liver content in the offspring as young adults, even after taking into account OWOB status and lifestyle factors in the offspring.

TWEETABLE ABSTRACT

There was an association between pre-pregnancy overweight and the development of NAFLD in adult offspring.

Maternal diet intervention before pregnancy primes offspring lipid metabolism in liver

Nonalcoholic fatty liver disease (NAFLD) has a developmental origin and is influenced in utero. We aimed to evaluate if maternal diet intervention before pregnancy would be beneficial to reduce the risk of offspring NAFLD. In our study, female mice were either on a normal-fat diet (NF group), or a high-fat diet for 12 weeks and continued on this diet throughout pregnancy and lactation (HF group), or switched from HF-to-NF diet 1 week (H1N group), or 9 weeks (H9N group) before pregnancy. Compared with the NF offspring, the H1N and HF, but not the H9N offspring, displayed more severe hepatic steatosis and glucose intolerance. More specifically, an abnormal blood lipid panel was seen in the H1N offspring and abnormal hepatic free fatty acid composition was present in both the HF and H1N offspring, while the H9N offspring displayed both at normal levels. These physiological changes were associated with desensitized hepatic insulin/AKT signaling, increased expression of genes and proteins for de novo lipogenesis and cholesterol synthesis, decreased expression of genes and proteins for fatty acid oxidation, increased Pcsk9 expression, and hypoactivation of 5' AMP-activated protein kinase (AMPK) signaling in the HF and H1N offspring. However, these effects were completely or partially rescued in the H9N offspring. In summary, we found that early maternal diet intervention is effective in reducing the risk of offspring NAFLD caused by maternal HF diet. These findings provide significant support to develop effective diet intervention strategies and policies for prevention of obesity and NAFLD to promote optimal health outcomes for mothers and children.

Differentiated Hepatic Response to Fructose Intake during Adolescence Reveals the Increased Susceptibility to Non-Alcoholic Fatty Liver Disease of Maternal High-Fat Diet Male Rat Offspring

SCOPE

Non-alcoholic fatty liver disease (NAFLD) among adolescents has been related to fructose intake. Additionally, maternal high-fat diet (mHFD) increases the offspring susceptibility to NAFLD at adulthood. Here, it is hypothesized that mHFD may exacerbate the fructose impact in adolescent male rat offspring, by changing the response of contributing mechanisms to liver injury.

METHODS AND RESULTS

Female Wistar rats receive standard (mSTD: 9% fat) or high-fat diet (mHFD: 29% fat) prior mating throughout pregnancy and lactation. After weaning, offspring receive standard chow and, from the 25th to 45th day, receive water or fructose-drinking water (15%). At 46 days old, fructose groups show increased adiposity, increased serum and hepatic triglycerides, regardless of maternal diet. Fructose aggravates the hepatic imbalance of redox state already exhibited by mHFD offspring. The hepatic activation of cellular repair pathways by fructose, such as unfolded protein response and macroautophagy, is disrupted only in mHFD offspring. Fructose does not change the liver morphology of mSTD offspring. However, it intensifies the liver injury already present in mHFD offspring.

CONCLUSION

Fructose intake during adolescence accelerates the emergence of NAFLD observed previously at the adult life of mHFD offspring, and reveals a differentiated hepatic response to metabolic insult, depending on the maternal diet.

Maternal Diet Alters Trained Immunity in the Pathogenesis of Pediatric NAFLD

Pediatric nonalcoholic fatty liver disease (NAFLD) affects 1 in 10 children in the US, increases risk of cirrhosis and transplantation in early adulthood, and shortens lifespan, even after transplantation. Exposure to maternal obesity and/or a diet high in fat, sugar and cholesterol is strongly associated with development of NAFLD in offspring. However, mechanisms by which "priming" of the immune system in early life increases susceptibility to NAFLD are poorly understood. Recent studies have focused on the role "non-reparative" macrophages play in accelerating inflammatory signals promoting fibrogenesis. In this Commentary, we review evidence that the pioneering gut bacteria colonizing the infant intestinal tract remodel the naïve immune system in the offspring. Epigenetic changes in hematopoietic stem and progenitor cells, induced by exposure to an obesogenic diet in utero, may skew lineage commitment of myeloid cells during gestation. Further, microbial dysbiosis in neonatal life contributes to training innate immune cell responsiveness in the gut, bone marrow, and liver, leading to developmental programming of pediatric NAFLD. Comprehensive understanding of how different gut bacteria and their byproducts shape development of the early innate immune system and microbiome will uncover early interventions to prevent NAFLD pathophysiology.