A Low ω-6 to ω-3 PUFA Ratio (n-6:n-3 PUFA) Diet to Treat Fatty Liver Disease in Obese Youth

The Effect of Tff3 Deficiency on the Liver of Mice Exposed to a High-Fat Diet

Background/Objectives: Trefoil factor protein 3 (Tff3) is a small peptide known as an epithelial tissue-protective protein, and it is also identified as a novel participant in complex metabolic processes. In numerous mouse models of obesity, Tff3 has been found to be downregulated in the liver and its overexpression is associated with an improvement in metabolic parameters. These mouse models with metabolic phenotypes have a multigenic background, with numerous genes contributing to their phenotype. To elucidate the role of Tff3 protein in metabolic events, we developed a mouse model with Tff3 deficiency on a C57Bl6N background without other intrinsic mutations affecting metabolism. Methods: We investigated the effects of a high-fat diet (9 weeks) on the liver of Tff3 protein-deficient mice of both sexes and the corresponding wild type. We investigated the general metabolic status of the animals and analysed the expression of markers of relevant pathophysiological pathways in the liver. Results:Tff3-deficient mice had significantly lower body weight. They also had a comparable total liver fat content but it was distributed in small vesicles, indicating the protective effect of Tff3 deficiency. The results of molecular analysis showed no major gene expression changes in inflammation-, ER- and oxidative stress-, and lipid metabolism-related genes. Tff3-/- males had reduced expression of Il1α and Cxcr7 genes in the liver and no global proteome changes; Tff3-deficient females had decreased expression of Irs2 and Atf4 genes and total proteome comparison showed decreased levels of proteins related to ribosome biosynthesis and the inhibition of acetylation. Conclusions: Our results demonstrate that Tff3 deficiency reduces lipid accumulation in the liver and we set the direction for further studies aimed at uncovering the exact molecular mechanisms in other organs. Furthermore, it emphasises the need to include both sexes in future research, as the observed phenotype differs significantly depending on sex.

Metabolic dysfunction-associated steatotic liver disease and omega-6 polyunsaturated fatty acids: Friends or foes

BACKGROUND

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common chronic liver disease worldwide. Its prevalence is closely linked to the dramatic rise in obesity and non-communicable diseases. MASLD exhibits a progressive trajectory that may culminate in development of hepatic cirrhosis, thereby predisposing affected individuals to an elevated likelihood of hepatocarcinogenesis. Diet, especially dietary fatty acids, serves as a key link between nutrient intake and MASLD pathogenesis.

AIM

To explore the impact of various omega-6 fatty acid subtypes on the pathogenesis and therapeutic strategies of MASLD.

METHODS

A systematic literature search was conducted across Web of Science, PubMed, Cochrane Central, Scopus, and Embase databases from inception through June 2024 to identify all original studies linking different subtypes of omega-6 polyunsaturated fatty acids to the pathogenesis and management of MASLD. The search strategy explored the linkage between omega-6 polyunsaturated fatty acids and their subtypes, including linoleic acid (LA), gamma-linolenic acid (GLA), arachidonic acid, conjugated LA, and docosapentaenoic acid, in relation to MASLD and cardiometabolic risk.

RESULTS

By employing the specified search strategy, a total of 83 articles were identified as potentially eligible. During the title, abstract, and full-text screening phases, 27 duplicate records were removed, leaving 56 records for relevance screening. Of these, 43 records were excluded for reasons such as irrelevance and language restrictions (limited to English), resulting in 13 full-text articles being included for detailed assessment (10 human studies,1 animal study, and 2 review articles). Although certain subtypes, as GLA, dihomo-GLA, omega-6-derived oxylipins, and most arachidonic acid-derived eicosanoids, exhibit pro-inflammatory effects, our findings suggest that other subtypes such as LA, cis-9, trans-11 conjugated LA, and docosapentaenoic acid have beneficial effects on fatty liver, cardiometabolic risk factors, and inflammation, even at high intake levels.

CONCLUSION

The varying health effects of omega-6 fatty acids, ranging from anti-inflammatory to pro-inflammatory impacts on the liver, leave the question of their recommendation for MASLD patients unresolved. This underscores the importance of careful selection when considering omega-6 supplementation.

The Potential of Metabolomics as a Tool for Identifying Biomarkers Associated with Obesity and Its Complications: A Scoping Review

Obesity and its related diseases, such as type 2 diabetes (T2DM), cardiovascular disease (CVD), and metabolic fatty liver disease (MAFLD), require new diagnostic markers for earlier detection and intervention. The aim of this study is to demonstrate the potential of metabolomics as a tool for identifying biomarkers associated with obesity and its comorbidities in every age group. The presented systematic review makes an important contribution to the understanding of the potential of metabolomics in identifying biomarkers of obesity and its complications, especially considering the influence of branched-chain amino acids (BCAAs), amino acids (AAs) and adipokines on the development of T2DM, MAFLD, and CVD. The unique element of this study is the combination of research results from the last decade in different age groups and a wide demographic range. The review was based on the PubMed and Science Direct databases, and the inclusion criterion was English-language original studies conducted in humans between 2014 and 2024 and focusing on the influence of BCAAs, AAs or adipokines on the above-mentioned obesity complications. Based on the PRISMA protocol, a total of 21 papers were qualified for the review and then assigned to a specific disease entity. The collected data reveal that elevated levels of BCAAs and some AAs strongly correlate with insulin resistance, leading to T2DM, MAFLD, and CVD and often preceding conventional clinical markers. Valine and tyrosine emerge as potential markers of MAFLD progression, while BCAAs are primarily associated with insulin resistance in various demographic groups. Adipokines, although less studied, offer hope for elucidating the metabolic consequences of obesity. The review showed that in the case of CVDs, there is still a lack of studies in children and adolescents, who are increasingly affected by these diseases. Moreover, despite the knowledge that adipokines play an important role in the pathogenesis of obesity, there are no precise findings regarding the correlation between individual adipokines and T2DM, MAFLD, or CVD. In order to be able to introduce metabolites into the basic diagnostics of obesity-related diseases, it is necessary to develop panels of biochemical tests that will combine them with classical markers of selected diseases.

Obesity and dyslipidemia in early life: Impact on cardiometabolic risk

Childhood obesity with its growing prevalence worldwide presents one of the most important health challenges nowadays. Multiple mechanisms are involved in the development of this condition, as well as in its associations with various cardiometabolic complications, such as insulin resistance, diabetes, metabolic dysfunction-associated steatotic liver disease and cardiovascular diseases. Recent findings suggest that childhood obesity and associated dyslipidemia at least partly originate from epigenetic modifications that take place in the earliest periods of life, namely prenatal and perinatal periods. Hence, alterations of maternal metabolism could be fundamentally responsible for fetal and neonatal metabolic programming and consequently, for metabolic health of offspring in later life. In this paper, we will review recent findings on the associations among intrauterine and early postnatal exposure to undesirable modulators of metabolism, development of childhood obesity and later cardiometabolic complications. Special attention will be given to maternal dyslipidemia as a driven force for undesirable epigenetic modulations in offspring. In addition, newly proposed lipid biomarkers of increased cardiometabolic risk in obese children and adolescents will be analyzed, with respect to their predictive potential and clinical applicability.

Pharmacological SERCA activation limits diet-induced steatohepatitis and restores liver metabolic function in mice

Metabolic dysfunction-associated steatotic liver disease is the most common form of liver disease and poses significant health risks to patients who progress to metabolic dysfunction-associated steatohepatitis. Fatty acid overload alters endoplasmic reticulum (ER) calcium stores and induces mitochondrial oxidative stress in hepatocytes, leading to hepatocellular inflammation and apoptosis. Obese mice have impaired liver sarco/ER Ca2+-ATPase (SERCA) function, which normally maintains intracellular calcium homeostasis by transporting Ca2+ ions from the cytoplasm to the ER. We hypothesized that restoration of SERCA activity would improve diet-induced steatohepatitis in mice by limiting ER stress and mitochondrial dysfunction. WT and melanocortin-4 receptor KO (Mc4r-/-) mice were placed on either chow or Western diet (WD) for 8 weeks. Half of the WD-fed mice were administered CDN1163 to activate SERCA, which reduced liver fibrosis and inflammation. SERCA activation also restored glucose tolerance and insulin sensitivity, improved histological markers of metabolic dysfunction-associated steatohepatitis, increased expression of antioxidant enzymes, and decreased expression of oxidative stress and ER stress genes. CDN1163 decreased hepatic citric acid cycle flux and liver pyruvate cycling, enhanced expression of mitochondrial respiratory genes, and shifted hepatocellular [NADH]/[NAD+] and [NADPH]/[NADP+] ratios to a less oxidized state, which was associated with elevated PUFA content of liver lipids. In sum, the data demonstrate that pharmacological SERCA activation limits metabolic dysfunction-associated steatotic liver disease progression and prevents metabolic dysfunction induced by WD feeding in mice.

Role of dietary nutrients and metabolism in colorectal cancer

Colorectal cancer (CRC) is one of the most common malignancies and the leading causes of cancer related deaths worldwide. The development of CRC is driven by a combination of genetic and environmental factors. There is growing evidence that changes in dietary nutrition may modulate the CRC risk, and protective effects on the risk of developing CRC have been advocated for specific nutrients such as glucose, amino acids, lipid, vitamins, micronutrients and prebiotics. Metabolic crosstalk between tumor cells, tumor microenvironment components and intestinal flora further promote proliferation, invasion and metastasis of CRC cells and leads to treatment resistance. This review summarizes the research progress on CRC prevention, pathogenesis, and treatment by dietary supplementation or deficiency of glucose, amino acids, lipids, vitamins, micronutri-ents, and prebiotics, respectively. The roles played by different nutrients and dietary crosstalk in the tumor microenvironment and metabolism are discussed, and nutritional modulation is inspired to be beneficial in the prevention and treatment of CRC.

Maternal Diet High in Linoleic Acid Alters Offspring Lipids and Hepatic Regulators of Lipid Metabolism in an Adolescent Rat Model

Linoleic acid (LA), an n-6 polyunsaturated fatty acid (PUFA), is essential for fetal growth and development. A maternal high LA (HLA) diet alters cardiovascular development in adolescent rats and hepatic function in adult rats in a sex-specific manner. We investigated the effects of an HLA diet on adolescent offspring hepatic lipids and hepatic lipid metabolism gene expression, and the ability of the postnatal diet to alter these effects. Female Wistar Kyoto rats were fed low LA (LLA; 1.44% energy from LA) or high LA (HLA; 6.21% energy from LA) diets during pregnancy and gestation/lactation. Offspring, weaned at postnatal day (PN) 25, were fed LLA or HLA and euthanised at PN40 (n = 6-8). Maternal HLA increased circulating uric acid, decreased hepatic cholesterol and increased hepatic Pparg in males, whereas only hepatic Srebf1 and Hmgcr increased in females. Postnatal (post-weaning) HLA decreased liver weight (% body weight) and increased hepatic Hmgcr in males, and decreased hepatic triglycerides in females. Maternal and postnatal HLA had an interaction effect on Lpl, Cpt1a and Pparg in females. These findings suggest that an HLA diet both during and after pregnancy should be avoided to improve offspring disease risk.

The Intersection of Genetic Factors, Aberrant Nutrient Metabolism and Oxidative Stress in the Progression of Cardiometabolic Disease

Cardiometabolic disease (CMD), which encompasses metabolic-associated fatty liver disease (MAFLD), chronic kidney disease (CKD) and cardiovascular disease (CVD), has been increasing considerably in the past 50 years. CMD is a complex disease that can be influenced by genetics and environmental factors such as diet. With the increased reliance on processed foods containing saturated fats, fructose and cholesterol, a mechanistic understanding of how these molecules cause metabolic disease is required. A major pathway by which excessive nutrients contribute to CMD is through oxidative stress. In this review, we discuss how oxidative stress can drive CMD and the role of aberrant nutrient metabolism and genetic risk factors and how they potentially interact to promote progression of MAFLD, CVD and CKD. This review will focus on genetic mutations that are known to alter nutrient metabolism. We discuss the major genetic risk factors for MAFLD, which include Patatin-like phospholipase domain-containing protein 3 (PNPLA3), Membrane Bound O-Acyltransferase Domain Containing 7 (MBOAT7) and Transmembrane 6 Superfamily Member 2 (TM6SF2). In addition, mutations that prevent nutrient uptake cause hypercholesterolemia that contributes to CVD. We also discuss the mechanisms by which MAFLD, CKD and CVD are mutually associated with one another. In addition, some of the genetic risk factors which are associated with MAFLD and CVD are also associated with CKD, while some genetic risk factors seem to dissociate one disease from the other. Through a better understanding of the causative effect of genetic mutations in CMD and how aberrant nutrient metabolism intersects with our genetics, novel therapies and precision approaches can be developed for treating CMD.

Nutritional composition, health-promoting effects, bioavailability, and encapsulation of tree peony seed oil: a review

Tree peony is cultivated worldwide in large quantities due to its exceptional ornamental and medicinal value. In recent years, the edible value of tree peony seed oil (TPSO) has garnered significant attention for its high content of alpha-linolenic acid (ALA, >40%) and other beneficial minor components, including phytosterols, tocopherols, squalene, and phenolics. This review provides a systematic summary of the nutritional composition and health-promoting effects of TPSO, with a specific focus on its digestion, absorption, bioavailability, and encapsulation status. Additionally, information on techniques for extracting and identifying adulteration of TPSO, as well as its commercial applications and regulated policies, is included. Thanks to its unique nutrients, TPSO offers a wide range of health benefits, such as hypolipidemic, anti-obesity, cholesterol-lowering, antioxidant and hypoglycemic activities, and regulation of the intestinal microbiota. Consequently, TPSO shows promising potential in the food and cosmetic industries and should be cultivated in more countries. However, the application of TPSO is hindered by its low bioavailability, poor stability, and limited water dispersibility. Therefore, it is crucial to develop effective delivery strategies, such as microencapsulation and emulsion, to overcome these limitations. In conclusion, this review provides a comprehensive understanding of the nutritional value of TPSO and emphasizes the need for further research on its nutrition and product development.

Time course of western diet (WD) induced nonalcoholic steatohepatitis (NASH) in female and male Ldlr-/- mice

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a global health problem. Identification of factors contributing to the onset and progression of NAFLD have the potential to direct novel strategies to combat NAFLD.

METHODS

We examined the time course of western diet (WD)-induced NAFLD and its progression to nonalcoholic steatohepatitis (NASH) in age-matched female and male Ldlr-/- mice, with time-points at 1, 4, 8, 20 and 40 weeks on the WD. Controls included Ldlr-/- mice maintained on a purified low-fat diet (LFD) for 1 and 40 weeks. The approach included quantitation of anthropometric, plasma and liver markers of disease, plus hepatic histology, lipids, oxylipins, gene expression and selected metabolites.

RESULTS

One week of feeding the WD caused a significant reduction in hepatic essential fatty acids (EFAs: 18:2, ω6, 18:3, ω3) which preceded the decline in many C20-22 ω3 and ω6 polyunsaturated fatty acids (PUFA) and PUFA-derived oxylipins after 4 weeks on the WD. In addition, expression of hepatic inflammation markers (CD40, CD44, Mcp1, Nlrp3, TLR2, TLR4, Trem2) increased significantly in both female & male mice after one week on the WD. These markers continued to increase over the 40-week WD feeding study. WD effects on hepatic EFA and inflammation preceded all significant WD-induced changes in body weight, insulin resistance (HOMA-IR), oxidative stress status (GSH/GSSG ratio) and histological and gene expression markers of macrosteatosis, extracellular matrix remodeling and fibrosis.

CONCLUSIONS

Our findings establish that feeding Ldlr-/- mice the WD rapidly lowered hepatic EFAs and induced key inflammatory markers linked to NASH. Since EFAs have an established role in inflammation and hepatic inflammation plays a major role in NASH, we suggest that early clinical assessment of EFA status and correcting EFA deficiencies may be useful in reducing NASH severity.

Early transcriptome changes associated with western diet induced NASH in Ldlr-/- mice points to activation of hepatic macrophages and an acute phase response

Background

Nonalcoholic fatty liver disease (NAFLD) is a global health problem. Identifying early gene indicators contributing to the onset and progression of NAFLD has the potential to develop novel targets for early therapeutic intervention. We report on the early and late transcriptomic signatures of western diet (WD)-induced nonalcoholic steatohepatitis (NASH) in female and male Ldlr-/- mice, with time-points at 1 week and 40 weeks on the WD. Control Ldlr-/- mice were maintained on a low-fat diet (LFD) for 1 and 40 weeks.

Methods

The approach included quantitation of anthropometric and hepatic histology markers of disease as well as the hepatic transcriptome.

Results

Only mice fed the WD for 40 weeks revealed evidence of NASH, i.e., hepatic steatosis and fibrosis. RNASeq transcriptome analysis, however, revealed multiple cell-specific changes in gene expression after 1 week that persisted to 40 weeks on the WD. These early markers of disease include induction of acute phase response (Saa1-2, Orm2), fibrosis (Col1A1, Col1A2, TGFβ) and NASH associated macrophage (NAM, i.e., Trem2 high, Mmp12 low). We also noted the induction of transcripts associated with metabolic syndrome, including Mmp12, Trem2, Gpnmb, Lgals3 and Lpl. Finally, 1 week of WD feeding was sufficient to significantly induce TNFα, a cytokine involved in both hepatic and systemic inflammation.

Conclusion

This study revealed early onset changes in the hepatic transcriptome that develop well before any anthropometric or histological evidence of NALFD or NASH and pointed to cell-specific targeting for the prevention of disease progression.

Plasma Fatty Acid Composition, Oxidative and Inflammatory Status, and Adherence to the Mediterranean Diet of Patients with Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a complex and increasingly prevalent cardiometabolic disorder worldwide. As of today, NAFLD is a pathology without specific pharmacological treatment, with the Mediterranean diet (MedDiet) being the most widely used approach for its management. The objective of this study is to assess the effects of adherence to the Mediterranean diet on fatty acid plasma levels, as well as on the oxidative and inflammatory status of NAFLD patients. A total of 100 adult patients (40-60 years old) diagnosed with NAFLD and from the Balearic Islands, Spain, were classified into three groups according to their adherence to the MedDiet. Consumption was assessed using a validated 143-item semiquantitative Food Frequency Questionnaire. Food items (g/day) were categorised according to their processing using the NOVA system. Anthropometrics, blood pressure, aminotransferases, Dietary Inflammatory Index (DII), inflammatory biomarkers, and fatty acid levels were measured in the plasma of NAFLD patients. High adherence to the MedDiet is associated to a highly plant-based diet, low ultra-processed food (UPF) consumption, low intake of dietary lipids, low intake of animal fats, high intake of monounsaturated fatty acid (MUFA; mainly palmitoleic acid), low intake of saturated fatty acids (SFAs; practically all dietary SFAs), low intake of trans-fatty acids, high intake of omega-3 fatty acids (mainly eicosapentaenoic acid), a higher n-6:n-3 in ratio, low intake of omega-6 fatty acids, and a low level of interleukin-6 (IL-6). High adherence to the MedDiet is related to a better fatty acid profile in the plasma, fewer SFAs and more MUFA and polyunsaturated fatty acids (PUFAs), a plasma biochemical profile, better proinflammatory status, and decreased ultra-processed food consumption of NAFLD patients.

Effect of Nut Consumption on Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-Analysis

Although previous epidemiological studies have been conducted to investigate the relationship between nut consumption and the risk of nonalcoholic fatty liver disease (NAFLD), the evidence remains inconclusive and contentious. The aim of our study was to further conduct a meta-analysis of observational studies to explore the latest evidence of the influence of nut consumption on NAFLD. This meta-analysis included a comprehensive search of all articles published in the PubMed and Web of Science online databases as of April 2023. A total of 11 articles were included, comprising 2 prospective cohort studies, 3 cross-sectional studies, and 7 case-control studies, and a random effects model was used to evaluate the relationship between nuts and NAFLD. Results showed that the odds ratio (OR) of NAFLD was 0.90 (95% CI: 0.81-0.99, p < 0.001) when comparing the highest and lowest total nut intake, indicating a significant negative correlation. Furthermore, subgroup analysis revealed that the protective effect of nuts on NAFLD was more significant in females (OR = 0.88; 95% CI: 0.78-0.98, I² = 76.2%). In summary, our findings provide support for a protective relationship between nut intake and risk of NAFLD. Further exploration of the association between other dietary components and NAFLD is an important avenue for future research.

Effects of Tylophora yunnanensis Schltr on regulating the gut microbiota and its metabolites in non-alcoholic steatohepatitis rats by inhibiting the activation of NOD-like receptor protein 3

ETHNOPHARMACOLOGICAL RELEVANCE

Tylophora yunnanensis Schltr (TYS) is widely distributed in Yunnan, Guizhou, and other places in China. It is commonly used by folks to treat hepatitis and other liver-related diseases; however, its mechanism of action is still unclear.

AIM OF THE STUDY

This study aimed to determine the effects of TYS on regulating gut microbiota and its metabolites in non-alcoholic steatohepatitis (NASH) rats by inhibiting the activation of NOD-like receptor protein3 (NLRP3).

MATERIAL AND METHODS

An HFD-induced rat model was established to investigate if the intragastric administration of TYS could mediate gut microbiota and their metabolites to ultimately improve the symptoms of NASH. The improving effects of TYS on NASH rats were assessed by measuring their body weight, lipid levels, histopathology, and inflammatory factor levels in the rat models. The regulatory effects of TYS on NLRP3 in the NASH rats were analyzed using real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) and enzyme-linked immunosorbent assay (ELISA), which determined the levels of NLRP3-related factors. The changes in the composition of the gut microbiota of NASH rats were analyzed using 16S rRNA gene sequencing technology. Meanwhile, the Ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was used for the non-targeted analysis of metabolites in the cecum contents.

RESULTS

The results showed that TYS could improve NASH by decreasing the body weight and levels of lipid, AST, ALT, LPS, FFA, VLDL, IL-1β, IL-6, TNF-α, TGF-β, NLRP3, ASC, and Caspase-1 in the NASH rats. The analysis of gut microbiota showed that TYS could improve the diversity and abundance of gut microbiota and alter their composition by decreasing the Firmicutes/Bacteroidetes (F/B) ratio and relative abundances of Lachnospiraceae, Christensenellaceae, Blautia, etc. while increasing those of Muribaculaceae, Rumiaococcus, Ruminococcaceae, etc. The analysis of metabolites in the cecum contents suggested that the arachidonic acid metabolism, bile secretion, serotonergic synapse, Fc epsilon RI signaling pathway, etc. were regulated by TYS. The metabolites enriched in these pathways mainly included chenodeoxycholic acid, prostaglandin D2, TXB2, 9-OxoODE, and 13(S)-HOTrE.

CONCLUSIONS

These findings suggested that TYS could alleviate the NASH symptoms by decreasing the body weight, regulating the lipid levels, reducing the inflammatory response, and inhibiting the expression levels of NLRP3, ASC, and Caspase-1 in the NASH rats. The changes in the composition of gut microbiota and their metabolic disorder were closely related to the activation of NLRP3. TYS could significantly inhibit the activation of NLRP3 and regulate the composition of gut microbiota and the disorder of metabolites during NASH modeling.

Omega-3 fatty acids supplements for dry eye - Are they effective or ineffective?

Purpose

To evaluate effectiveness of omega-3 fatty acid supplements in relieving dry eye symptoms and signs in symptomatic visual display terminal users (VDT).

Methods

A randomized controlled study was done; eyes of 470 VDT users were randomized to receive four capsules twice daily for 6 months (O3FAgroup), each containing 180 mg of eicosapentaenoic acid and 120 mg docosahexaenoic acid. The O3FA group was compared with another group (n = 480) who received four capsules of a placebo (olive oil) twice daily. Patients were evaluated at baseline, 1, 3, and 6 months, respectively. The primary outcome was improvement in omega-3 index (a measure of EPA and DHA ratio in RBC membrane). Secondary outcomes were improvement dry eye symptoms, Nelson grade on conjunctival impression cytology, Schirmer test values, tear film breakup time (TBUT), and tear film osmolarity. Means of groups (pre-treatment, 1, 3, and 6-months) were compared with repeated measure analysis of variance.

Results

At baseline, 81% patients had low omega-3 index. In the O3FA group, a significant increase in omega-3 index, improvement in symptoms, reduction in tear film osmolarity, and increase in Schirmer, TBUT, and goblet cell density was observed. These changes were not significant in the placebo group. Improvement in test parameters was significantly (P < 0.001) better in patients with low omega3 index (<4%) subgroup.

Conclusion

Dietary omega-3 fatty acids are effective for dry eye in VDT users; omega-3 index appears to be the predictor to identify potential dry eye patients who are likely to benefit from oral omega-3 dietary intervention.

Recent evaluation about inflammatory mechanisms in nonalcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is common chronic metabolic liver disorder which is associated with fat accumulation in the liver. It causes a wide range of pathological effects such as insulin resistance, obesity, hypertension, diabetes, non-alcoholic steatohepatitis (NASH) and cirrhosis, cardiovascular diseases. The molecular mechanisms that cause the initiation and progression of NAFLD remain fully unclear. Inflammation is regarded as a significant mechanism which could result in cell death and tissue injury. Accumulation of leukocytes and hepatic inflammation are important contributors in NAFLD. Excessive inflammatory response can deteriorate the tissue injury in NAFLD. Thus, inhibition of inflammation improves NAFLD by reducing intrahepatic fat content, increasing β-oxidation of fatty acids, inducing hepato-protective autophagy, overexpressing peroxisome proliferator-activated receptor- γ (PPAR-γ), as well as attenuating hepatocyte apoptosis and increasing insulin sensitivity. Therefore, understanding the molecules and signaling pathways suggests us valuable information about NAFLD progression. This review aimed to evaluate the inflammation in NAFLD and the molecular mechanism on NAFLD.

Partial replacement of high-fat diet with n-3 PUFAs enhanced beef tallow attenuates dyslipidemia and endoplasmic reticulum stress in tunicamycin-injected rats

Introduction

Metabolic syndrome (MetS) is considered as a complex, intertwined multiple risk factors that directly increase the risk of various metabolic diseases, especially cardiovascular atherosclerotic diseases and diabetes mellitus type 2. While lifestyle changes, including dietary intervention are effective in mitigating or preventing MetS, there are no specific therapies against MetS. Typical western diets comprise of high saturated fatty acid, cholesterol, and simple sugar; consequently their consumption may increase the potential pathological developmental risk of MetS. Partial replacement of dietary fatty acids with polyunsaturated fatty acids (PUFAs) is widely recommended measure to manage MetS-related disorders.

Methods

In the present study, we used rat model to investigate the role of n-3 PUFA enriched beef tallows (BT) on MetS and tunicamycin (TM)-induced endoplasmic reticulum (ER) stress, by partially replacing dietary fat (lard) with equal amounts of two different BTs; regular BT or n-3 PUFA-enriched BT. The experimental rats were randomly assigned to three different dietary groups (n = 16 per group): (1) high-fat and high-cholesterol diet (HFCD); (2) HFCD partially replaced with regular BT (HFCD + BT1); (3) HFCD partially replaced with n-3 enhanced BT (w/w) (HFCD + BT2). After 10 weeks of dietary intervention, each experimental rodent was intraperitoneally injected with either phosphate-buffered saline or 1 mg/kg body weight of TM.

Results

HFCD + BT2 showed improved dyslipidemia before TM injection, and increased serum high-density lipoprotein cholesterol (HDL-C) levels after TM injection. BT replacement groups had significantly reduced hepatic triglyceride (TG) levels, and decreased total cholesterol (TC) and TG levels in epididymal adipose tissue (EAT). Furthermore, BT replacement remarkably attenuated TM-induced unfolded protein responses (UPRs) in liver, showing reduced ER stress, with BT2 being more effective in the EAT.

Discussion

Therefore, our findings suggest that partially replacing dietary fats with n-3 PUFA to lower the ratio of n-6/n-3 PUFAs is beneficial in preventing pathological features of MetS by alleviating HFCD- and/or TM-induced dyslipidemia and ER stress.

Unsaturated Fatty Acids and Their Immunomodulatory Properties

Oils are an essential part of the human diet and are primarily derived from plant (or sometimes fish) sources. Several of them exhibit anti-inflammatory properties. Specific diets, such as Mediterranean diet, that are high in ω-3 polyunsaturated fatty acids (PUFAs) and ω-9 monounsaturated fatty acids (MUFAs) have even been shown to exert an overall positive impact on human health. One of the most widely used supplements in the developed world is fish oil, which contains high amounts of PUFAs docosahexaenoic and eicosapentaenoic acid. This review is focused on the natural sources of various polyunsaturated and monounsaturated fatty acids in the human diet, and their role as precursor molecules in immune signaling pathways. Consideration is also given to their role in CNS immunity. Recent findings from clinical trials utilizing various fatty acids or diets high in specific fatty acids are reviewed, along with the mechanisms through which fatty acids exert their anti-inflammatory properties. An overall understanding of diversity of polyunsaturated fatty acids and their role in several molecular signaling pathways is useful in formulating diets that reduce inflammation and increase longevity.

Eating, diet, and nutrition for the treatment of non-alcoholic fatty liver disease

Nutrition and dietary interventions are a central component in the pathophysiology, but also a cornerstone in the management of patients with non-alcoholic fatty liver disease (NAFLD). Summarizing our rapidly advancing understanding of how our diet influences our metabolism and focusing on specific effects on the liver, we provide a comprehensive overview of dietary concepts to counteract the increasing burden of NAFLD. Specifically, we emphasize the importance of dietary calorie restriction independently of the macronutrient composition together with adherence to a Mediterranean diet low in added fructose and processed meat that seems to exert favorable effects beyond calorie restriction. Also, we discuss intermittent fasting as a type of diet specifically tailored to decrease liver fat content and increase ketogenesis, awaiting future study results in NAFLD. Finally, personalized dietary recommendations could be powerful tools to increase the effectiveness of dietary interventions in patients with NAFLD considering the genetic background and the microbiome, among others.

Different ratios of DHA/EPA reverses insulin resistance by improving adipocyte dysfunction and lipid disorders in HFD-induced IR mice

Objective: Insulin resistance (IR) is linked to the development of diabetes, non-alcoholic fatty liver disease (NAFLD), and cardiovascular disease (CVDs). Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) from fish oils (FOs) were used to investigate their potential in high-fat diet (HFD)-induced IR mice under different ratios. Methods: A total of 84 male C57BL/6J (6 weeks old) mice were fed with HFD containing 45% kcal from fat for 16 weeks to establish the IR model. The IR mice were then fed with HFD or HFD + 4% DHA/EPA with different ratios (3 : 1, 1.5 : 1, 1 : 1, 1 : 1.5, 1 : 3, respectively) for another 12 weeks. During the experiment, the CON group (n = 12) was set to feed with a basic diet containing 10% kcal from fat. Results: HFD feeding for 16 weeks reduced insulin sensitivity and accelerated hypertrophy of white adipose tissue (WAT). Different ratios of DHA/EPA except for 1 : 1 decreased the HOMA-IR index, average area of adipocytes, and serum MDA, but increased the protein expression of PI3K. All ratios of DHA/EPA increased the protein expression of IRS-1, GLUT4, and adiponectin. Moreover, dietary DHA/EPA changed serum fatty acid (FA) composition by increasing the serum concentration of n-3 PUFAs. DHA/EPA supplements also improved serum lipid profiles (TG/TC/LDL-c/HDL-c, FFA) and reduced the hepatic steatosis area. Conclusions: The results indicate that an appropriate higher ratio of DHA (1.5 : 1) in DHA/EPA supplementation is recommended for IR prevention.

Nutritional Genomics in Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is a common chronic condition associated with genetic and environmental factors in which fat abnormally accumulates in the liver. NAFLD is epidemiologically associated with obesity, type 2 diabetes, and dyslipidemia. Environmental factors, such as physical inactivity and an unbalanced diet, interact with genetic factors, such as epigenetic mechanisms and polymorphisms for the genesis and development of the condition. Different genetic polymorphisms seem to be involved in this context, including variants in PNPLA3, TM6SF2, PEMT, and CHDH genes, playing a role in the disease's susceptibility, development, and severity. From carbohydrate intake and weight loss to omega-3 supplementation and caloric restriction, different dietary and nutritional factors appear to be involved in controlling the onset and progression of NAFLD conditions influencing metabolism, gene, and protein expression. The polygenic risk score represents a sum of trait-associated alleles carried by an individual and seems to be associated with NAFLD outcomes depending on the dietary context. Understanding the exact extent to which lifestyle interventions and genetic predispositions can play a role in the prevention and management of NAFLD can be crucial for the establishment of a personalized and integrative approach to patients.

Clinical features and metabolic complications for non-alcoholic fatty liver disease (NAFLD) in youth with obesity

Pediatric obesity has become in the last forty years the most common metabolic disease in children and adolescents affecting about 25% of the pediatric population in the western world. As obesity worsens, a whole-body insulin resistance (IR) occurs. This phenomenon is more pronounced during adolescence, when youth experience a high degree of insulin resistance due the production of growth hormone. As IR progresses, the blunted control of insulin on adipose tissue lipolysis causes an increased flux of fatty acids with FFA deposition in ectopic tissues and organs such as the liver, leading to the development of NAFLD. In this brief review, we will discuss the clinical implications of IR and NAFLD in the context of pediatric obesity. We will review the pathogenesis and the link between these two entities, the major pathophysiologic underpinnings, including the role of genetics and metagenomics, how these two entities lead to the development of type 2 diabetes, and which are the therapeutic options for NAFLD in youth.

We are what we eat: The role of lipids in metabolic diseases

Lipids play a fundamental role, both structurally and functionally, for the correct functioning of the organism. In the last two decades, they have evolved from molecules involved only in energy storage to compounds that play an important role as components of cell membranes and signaling molecules that regulate cell homeostasis. For this reason, their interest as compounds involved in human health has been gaining weight. Indeed, lipids derived from dietary sources and endogenous biosynthesis are relevant for the pathophysiology of numerous diseases. There exist pathological conditions that are characterized by alterations in lipid metabolism. This is particularly true for metabolic diseases, such as liver steatosis, type 2 diabetes, cancer and cardiovascular diseases. The main issue to be considered is lipid homeostasis. A precise control of fat homeostasis is required for a correct regulation of metabolic pathways and safe and efficient energy storage in adipocytes. When this fails, a deregulation occurs in the maintenance of systemic metabolism. This happens because an increased concentrations of lipids impair cellular homeostasis and disrupt tissue function, giving rise to lipotoxicity. Fat accumulation results in many alterations in the physiology of the affected organs, mainly in metabolic tissues. These alterations include the activation of oxidative and endoplasmic reticulum stress, mitochondrial dysfunction, increased inflammation, accumulation of bioactive molecules and modification of gene expression. In this chapter, we review the main metabolic diseases in which alterations in lipid homeostasis are involved and discuss their pathogenic mechanisms.

The association between eicosanoids and incident atrial fibrillation in the Framingham Heart Study

Chronic inflammation is a continuous low-grade activation of the systemic immune response. Whereas downstream inflammatory markers are associated with atrial fibrillation (AF), upstream inflammatory effectors including eicosanoids are less studied. To examine the association between eicosanoids and incident AF. We used a liquid chromatography-mass spectrometry for the non-targeted measurement of 161 eicosanoids and eicosanoid-related metabolites in the Framingham Heart Study. The association of each eicosanoid and incident AF was assessed using Cox proportional hazards models and adjusted for AF risk factors, including age, sex, height, weight, systolic/diastolic blood pressure, current smoking, antihypertensive medication, diabetes, history of myocardial infarction and heart failure. False discovery rate (FDR) was used to adjust for multiple testing. Eicosanoids with FDR < 0.05 were considered significant. In total, 2676 AF-free individuals (mean age 66 ± 9 years, 56% females) were followed for mean 10.8 ± 3.4 years; 351 participants developed incident AF. Six eicosanoids were associated with incident AF after adjusting for multiple testing (FDR < 0.05). A joint score was built from the top eicosanoids weighted by their effect sizes, which was associated with incident AF (HR = 2.72, CI = 1.71-4.31, P = 2.1 × 10^-5). In conclusion, six eicosanoids were associated with incident AF after adjusting for clinical risk factors for AF.

Vitamin D and ω-3 Polyunsaturated Fatty Acids towards a Personalized Nutrition of Youth Diabetes: A Narrative Lecture

After the discovery of insulin, nutrition has become central in the management of diabetes in order to limit glycemic rise after meals, optimize metabolic control, and prevent complications. Over the past one hundred years, international scientific societies have consecutively refined nutritional needs and optimized food intake for the treatment of diabetes. In particular, over the past century, nutrition applied with pumps for the administration of insulin and continuous glucose monitoring have allowed substantial advancement in the treatment of type 1 diabetes mellitus. The role of some substances, such as vitamin D and n-3 polyunsaturated fatty acids, have been proposed without univocal conclusions, individually or in combination, or in the diet, to improve the nutrition of type 1 and type 2 diabetes. This second condition, which is highly associated with overweight, should be prevented from childhood onwards. Personalized nutrition could bypass the problem, reaching a scientific conclusion on the individual subject. This article focuses on childhood and adolescent diabetes, aims to provide a narrative summary of nutrition over the past century, and promotes the concept of personalized nutrition to pediatricians and pediatric diabetologists as a possible tool for the treatment of type 1 diabetes and the prevention of type 2 diabetes.

Multi-Omics Nutritional Approaches Targeting Metabolic-Associated Fatty Liver Disease

Currently, metabolic-associated fatty liver disease (MAFLD) is a leading global cause of chronic liver disease, and is expected to become one of the most common indications of liver transplantation. MAFLD is associated with obesity, involving multiple mechanisms such as alterations in lipid metabolism, insulin resistance, hyperinflammation, mitochondrial dysfunction, cell apoptosis, oxidative stress, and extracellular matrix formation. However, the onset and progression of MAFLD is variable among individuals, being influenced by intrinsic (personal) and external environmental factors. In this context, sequence structural variants across the human genome, epigenetic phenomena (i.e., DNA methylation, histone modifications, and long non-coding RNAs) affecting gene expression, gut microbiota dysbiosis, and metabolomics/lipidomic fingerprints may account for differences in MAFLD outcomes through interactions with nutritional features. This knowledge may contribute to gaining a deeper understanding of the molecular and physiological processes underlying MAFLD pathogenesis and phenotype heterogeneity, as well as facilitating the identification of biomarkers of disease progression and therapeutic targets for the implementation of tailored nutritional strategies. This comprehensive literature review highlights the potential of nutrigenetic, nutriepigenetic, nutrimetagenomic, nutritranscriptomics, and nutrimetabolomic approaches for the prevention and management of MAFLD in humans through the lens of precision nutrition.

The effects of rhein on D-GalN/LPS-induced acute liver injury in mice: Results from gut microbiome-metabolomics and host transcriptome analysis

Background

Rhubarb is an important traditional Chinese medicine, and rhein is one of its most important active ingredients. Studies have found that rhein can improve ulcerative colitis by regulating gut microbes, but there are few reports on its effects on liver diseases. Therefore, this study aims to investigate these effects and underlying mechanisms.

Methods

Mice were given rhein (100 mg/kg), with both a normal control group and a model group receiving the same amount of normal saline for one week. Acute liver injury was induced in mice by intraperitoneal injection of D-GalN (800 mg/kg)/LPS (10 ug/kg). Samples (blood, liver, and stool) were then collected and assessed for histological lesions and used for 16S rRNA gene sequencing, high-performance liquid chromatography-mass spectrometry (LC-MS) and RNA-seq analysis.

Results

The levels of ALT and AST in the Model group were abnormal higher compared to the normal control group, and the levels of ALT and AST were significantly relieved in the rhein group. Hepatic HE staining showed that the degree of liver injury in the rhein group was lighter than that in the model group, and microbiological results showed that norank_o:Clostridia_UCG-014, Lachnoclostridium, and Roseburia were more abundant in the model group compared to the normal control group. Notably, the rhein treatment group showed reshaped disturbance of intestinal microbial community by D-GalN/LPS and these mice also had higher levels of Verrucomicrobia, Akkermansiaceae and Bacteroidetes. Additionally, There were multiple metabolites that were significantly different between the normal control group and the model group, such as L-α-amino acid, ofloxacin-N-oxide, 1-hydroxy-1,3-diphenylpropan-2-one,and L-4-hydroxyglutamate semialdehyde, but that returned to normal levels after rhein treatment. The gene expression level in the model group also changed significantly, various genes such as Cxcl2, S100a9, Tnf, Ereg, and IL-10 were up-regulated, while Mfsd2a and Bhlhe41 were down-regulated, which were recovered after rhein treatment.

Conclusion

Overall, our results show that rhein alleviated D-GalN/LPS-induced acute liver injury in mice. It may help modulate gut microbiota in mice, thereby changing metabolism in the intestine. Meanwhile, rhein also may help regulate genes expression level to alleviate D-GalN/LPS-induced acute liver injury.

Esterified Oxylipins: Do They Matter?

Oxylipins are oxygenated metabolites of fatty acids that share several similar biochemical characteristics and functions to fatty acids including transport and trafficking. Oxylipins are most commonly measured in the non-esterified form which can be found in plasma, free or bound to albumin. The non-esterified form, however, reflects only one of the possible pools of oxylipins and is by far the least abundant circulating form of oxylipins. Further, this fraction cannot reliably be extrapolated to the other, more abundant, esterified pool. In cells too, esterified oxylipins are the most abundant form, but are seldom measured and their potential roles in signaling are not well established. In this review, we examine the current literature on experimental oxylipin measurements to describe the lack in reporting the esterified oxylipin pool. We outline the metabolic and experimental importance of esterified oxylipins using well established roles of fatty acid trafficking in non-esterified fatty acids and in esterified form as components of circulating lipoproteins. Finally, we use mathematical modeling to simulate how exchange between cellular esterified and unesterified pools would affect intracellular signaling.. The explicit inclusion of esterified oxylipins along with the non-esterified pool has the potential to convey a more complete assessment of the metabolic consequences of oxylipin trafficking.

Effect of n-6/n-3 PUFA ratio on body fat deposition, tissues fatty acid composition and key genes expression of liver lipid metabolism in silver foxes (Vulpes vulpes fulva) during the winter fur-growth period

Objective

The proportion of n-6/n-3 polyunsaturated fatty acid (PUFA) plays an important role in regulating lipid metabolism. This study aimed to investigate the effects of dietary n-6/n-3 PUFA ratios on body fat deposition, tissues fatty acid composition, and gene expression of liver lipid metabolism of silver foxes during the winter fur growth period.

Methods

Forty-eight age-matched male silver foxes with similar body weights were randomly divided into four dietary groups for 47 days, which were fed n-6/n-3 PUFA ratio with 3, 18, 41, and 136 experimental diets, respectively.

Results

Dietary n-6/n-3 PUFA ratio did not significantly influence fat deposition parameters except for hepatic fat content. The variation trend of the fatty acid composition of liver, intramuscular fat, and subcutaneous fat in silver fox was directly related to dietary fatty acid content (p < 0.05). With the dietary n-6/n-3 PUFA ratio increasing, the expression of liver fatty acid synthase (FAS) mRNA and peroxisome proliferator-activated receptor (PPAR) mRNA exhibited the trend of first decreasing and then increasing (p < 0.05), whereas L-fatty acid binding protein (L-FABP) mRNA expression showed a gradual increasing trend (p < 0.05).

Conclusion

In summary, silver foxes fed an n-6/n-3 PUFA ratio 18:1 diet (supplementing with 9.38% corn oil and 4.62% soybean oil) was more conducive to lipid decomposition, PUFA transport, and utilization of tissues, thereby meeting it for supplying energy and withstanding the cold.

The role of oxidized lipid species in insulin resistance and NASH in children

During the last two decades, nonalcoholic fatty liver disease (NAFLD) has emerged as the most common hepatic disease in pediatrics, mainly owing to the rising prevalence of pediatric obesity. Epidemiological studies have shown that the progressive increase in NAFLD prevalence is associated not only with obesity but also with changes in dietary habits experienced by all age groups, characterized by the increased intake of added sugars and certain fatty acids. In this review article, we focus on the effect of oxidized fatty acids deriving from linoleic acid and arachidonic acid on the pathogenesis and progression of NAFLD in youth.

The function of omega-3 polyunsaturated fatty acids in response to cadmium exposure

Throughout history, pollution has become a part of our daily life with the improvement of life quality and the advancement of industry and heavy industry. In recent years, the adverse effects of heavy metals, such as cadmium (Cd), on human health have been widely discussed, particularly on the immune system. Here, this review summarizes the available evidence on how Cd exposure may affect health. By analyzing the general manifestations of inflammation caused by Cd exposure, we find that the role of omega-3 (n-3) polyunsaturated fatty acids (PUFAs) in vivo can counteract Cd-induced harm. Additionally, we elucidate the effects of n-3 PUFAs on the immune system, and analyze their prophylactic and therapeutic effects on Cd exposure. Overall, this review highlights the role of n-3 PUFAs in the pathological changes induced by Cd exposure. Although n-3 PUFAs remain to be verified whether they can be used as therapeutic agents, as rehabilitation therapy, supplementation with n-3 PUFAs is reliable and effective.

Physiopathology of nonalcoholic fatty liver disease: from diet to nutrigenomics

PURPOSE OF REVIEW

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide and is strongly associated with metabolic disorders, such as obesity, type 2 diabetes mellitus, and metabolic syndrome, to the extent that a new definition of metabolic associated fatty liver disease has been proposed.

RECENT FINDINGS

Insulin resistance, worsened by a high-fat and high-carbohydrate diet, is the key to the physiopathology of hepatic steatosis. This is driven by several mechanisms that are mostly activated at a genetic level, such as de-novo lipogenesis and triglyceride synthesis. Therefore, many diet regimens have been studied, although significant controversies remain regarding their metabolic effects and long-term sustainability.

SUMMARY

In this review, we summarized the role and effects of the main macronutrients on the development of NAFLD and discussed the molecular mechanisms involved. We also discussed the importance of genetic polymorphisms, epigenetic alterations, and dysbiosis to determine if lifestyle modification and a specific dietary regimen could be an essential part of NAFLD treatment.

Current knowledge of the implication of lipid mediators in psoriasis

The skin is an organ involved in several biological processes essential to the proper functioning of the organism. One of these essential biological functions of the skin is its barrier function, mediated notably by the lipids of the stratum corneum, and which prevents both penetration from external aggression, and transepidermal water loss. Bioactive lipid mediators derived from polyunsaturated fatty acids (PUFAs) constitute a complex bioactive lipid network greatly involved in skin homeostasis. Bioactive lipid mediators derived from n-3 and n-6 PUFAs have well-documented anti- and pro-inflammatory properties and are recognized as playing numerous and complex roles in the behavior of diverse skin diseases, including psoriasis. Psoriasis is an inflammatory autoimmune disease with many comorbidities and is associated with enhanced levels of pro-inflammatory lipid mediators. Studies have shown that a high intake of n-3 PUFAs can influence the development and progression of psoriasis, mainly by reducing the severity and frequency of psoriatic plaques. Herein, we provide an overview of the differential effects of n-3 and n-6 PUFA lipid mediators, including prostanoids, hydroxy-fatty acids, leukotrienes, specialized pro-resolving mediators, N-acylethanolamines, monoacylglycerols and endocannabinoids. This review summarizes current findings on lipid mediators playing a role in the skin and their potential as therapeutic targets for psoriatic patients.

A new nutraceutical (Livogen Plus®) improves liver steatosis in adults with non-alcoholic fatty liver disease

Background

Currently, there is no approved medication for non-alcoholic fatty liver disease management. Pre-clinical and clinical studies showed that several bioactive molecules in plants or foods (i.e., curcumin complex, bergamot polyphenol fraction, artichoke leaf extract, black seed oil, concentrate fish oil, picroliv root, glutathione, S-adenosyl-l-methionine and other natural ingredients) have been associated with improved fatty liver disease. Starting from these evidences, our purpose was to evaluate the effects of a novel combination of abovementioned nutraceuticals as a treatment for adults with fatty liver disease.

Methods

A total of 140 participants with liver steatosis were enrolled in a randomized, double-blind, placebo controlled clinical trial. The intervention group received six softgel capsules daily of a nutraceutical (namely Livogen Plus®) containing a combination of natural bioactive components for 12 weeks. The control group received six softgel capsules daily of a placebo containing maltodextrin for 12 weeks. The primary outcome measure was the change in liver fat content (CAP score). CAP score, by transient elastography, serum glucose, lipids, transaminases, and cytokines were measured at baseline and after intervention.

Results

After adjustment for confounding variables (i.e., CAP score and triglyceride at baseline, and changes of serum γGT, and vegetable and animal proteins, cholesterol intake at the follow-up), we found a greater CAP score reduction in the nutraceutical group rather than placebo (− 34 ± 5 dB/m vs. − 20 ± 5 dB/m, respectively; p = 0.045). The CAP score reduction (%) was even greater in those with aged 60 or less, low baseline HDL-C, AST reduction as well as in men.

Conclusion

Our results showed that a new combination of bioactive molecules as nutraceutical was safe and effective in reducing liver fat content over 12 weeks in individuals with hepatic steatosis.

Trial registration ISRCTN, ISRCTN70887063. Registered 03 August 2021—retrospectively registered, https://doi.org/10.1186/ISRCTN70887063

Insights from shotgun metagenomics into bacterial species and metabolic pathways associated with NAFLD in obese youth

Nonalcoholic fatty liver disease (NAFLD) is the most common form of liver disease and is often the precursor for more serious liver conditions such as nonalcoholic steatohepatitis and cirrhosis. Although the gut microbiome has been implicated in the development of NAFLD, the strong association of obesity with NAFLD and its effect on microbiome structure has made interpreting study outcomes difficult. In the present study, we examined the taxonomic and functional differences between the microbiomes of youth with obesity and with and without NAFLD. Shotgun metagenome sequencing was performed to profile the microbiomes of 36 subjects, half of whom were diagnosed with NAFLD using abdominal magnetic resonance imaging. Beta diversity analysis showed community-wide differences between the groups (p = 0.002). Specific taxonomic differences included increased relative abundances of the species Fusicatenibacter saccharivorans (p = 0.042), Romboutsia ilealis (p = 0.046), and Actinomyces sp. ICM47 (p = 0.0009), and a decrease of Bacteroides thetaiotamicron (p = 0.0002), in the NAFLD group as compared with the non-NAFLD group. At the phylum level, Bacteroidetes (p < 0.0001) was decreased in the NAFLD group. Functionally, branched-chain amino acid (p = 0.01343) and aromatic amino acid (p = 0.01343) synthesis pathways had increased relative abundances in the NAFLD group along with numerous energy use pathways, including pyruvate fermentation to acetate (p = 0.01318). Conclusion: Community-wide differences were noted based on NAFLD status, and individual bacterial species along with specific metabolic pathways were identified as potential drivers of these differences. The results of the present study support the idea that the NAFLD phenotype displays a differentiated microbial and functional signature from the obesity phenotype.

Metabolic dysfunction-associated fatty liver disease in obese youth with insulin resistance and type 2 diabetes

PURPOSE OF REVIEW

The aim of this review is to present the new definition of the disease, defining the epidemiology, risk factors with a particular attention to the role of insulin resistance (IR) and to define the main treatments explored.

RECENT FINDINGS

Nonalcoholic fatty liver disease (NAFLD) was previously considered a primary liver disease, but it would be more correct to consider it a component of the metabolic syndrome (MetS) in which IR might play a key role. Based on these findings, it has been recently proposed to modify the classic term of NAFLD to metabolic dysfunction-associated fatty liver disease (MAFLD) that better reflects the pathophysiology of this complex disease.

SUMMARY

Currently, no treatments approved in childhood are available, thus the only recommended approach is the prevention and correction of the known risk factors, and particularly of IR. However, further studies are needed to better clarify the pathogenetic mechanisms of NAFLD in order to establish more tailored therapies.

Dietary Acid Load (DAL), Glycated Hemoglobin A1c (HbA1c), and Metabolic Syndrome (MeS) Mediate the Association of the Adherence to the Dietary Approaches to Stopping Hypertension (DASH) and Mediterranean Diet (MeD) With Nonalcoholic Fatty Liver Disease

The study aimed to investigate the association of adults adhering to Dietary Approaches to Stop Hypertension (DASH) and Mediterranean diet (MeD) with nonalcoholic fatty liver disease (NAFLD) using structural equation modeling (SEM) in Iran. In this population-based cross-sectional study, 3,220 adults (44.65% female) aged ≥18 years were selected from the Amol Cohort Study (AmolCS). The dietary intakes were assessed by a validated 168-item semi-quantitative food-frequency questionnaire (FFQ). Residual method energy adjustment of MeD and DASH scores were calculated. Demographic characteristics and anthropometric and laboratory measurements were collected. NAFLD was diagnosed by an expert radiologist via ultrasound sonography. Based on the primary hypothesis, DASH, MeD, and NAFLD were fitted into models. Metabolic syndrome (MeS) as a potential risk factor directly affected NAFLD risk in all these models. In both genders, the higher adherence to DASH negatively affected NAFLD risk indirectly through the two following paths. (1) Dietary acid load (DAL) and metabolic syndrome (2) DAL and hemoglobin A1c (HbA1c). In addition, the higher DAL positively affected NAFLD risk among male participants indirectly via increasing HbA1c level and MeS (from DAL to HbA1c: β = 0.07, P < 0.001; from HbA1c to MeS: β = 0.10, P < 0.001). Similarly, in both genders, the relationship between MeD and NAFLD was mediated through (1) DAL, HbA1c, and MeS and (2) DAL and MeS. Further, among male participants, the MeD and NAFLD risk were also associated via the mediators of HbA1c and MeS. In female participants, the higher MeD score was directly associated with a reduction of NAFLD risk (β = -0.07, P = 0.008). The present study found three important mediators, including DAL, HbA1c, and MeS, in the association of DASH and MeD scores with NAFLD risk. Preventive and therapeutic interventions should target the mediators, including DAL, HbA1c, MeS, and its components, to reduce NAFLD incidence in the general population.

A low n-6 to n-3 polyunsaturated fatty acid ratio diet improves hyperinsulinaemia by restoring insulin clearance in obese youth

AIM

To examine the determinants and metabolic impact of the reduction in fasting and postload insulin levels after a low n-6 to n-3 polyunsaturated fatty acid (PUFA) ratio diet in obese youth.

MATERIALS AND METHODS

Insulin secretion and clearance were assessed by measuring and modelling plasma insulin and C-peptide in 17 obese youth who underwent a nine-point, 180-minute oral glucose tolerance test (OGTT) before and after a 12-week, eucaloric low n-6:n-3 polyunsaturated fatty acid (PUFA) ratio diet. Hepatic fat content was assessed by repeated abdominal magnetic resonance imaging.

RESULTS

Insulin clearance at fasting and during the OGTT was significantly increased after the diet, while body weight, glucose levels, absolute and glucose-dependent insulin secretion, and model-derived variables of β-cell function were not affected. Dietary-induced changes in insulin clearance positively correlated with changes in whole-body insulin sensitivity and β-cell glucose sensitivity, but not with changes in hepatic fat. Subjects with greater increases in insulin clearance showed a worse metabolic profile at enrolment, characterized by impaired insulin clearance, β-cell glucose sensitivity, and glucose tolerance, and benefitted the most from the diet, achieving greater improvements in glucose-stimulated hyperinsulinaemia, insulin resistance, and β-cell function.

CONCLUSIONS

We showed that a 12-week low n-6:n-3 PUFA ratio diet improves hyperinsulinaemia by increasing fasting and postload insulin clearance in obese youth, independently of weight loss, glucose concentrations, and insulin secretion.

Quality of Oil Pressed from Hemp Seed Varieties: 'Earlina 8FC', 'Secuieni Jubileu' and 'Finola'

In the last decade, the demand for edible niche oils has increased. Therefore, the aim of this study was to characterize the seeds hemp (Cannabis sativa L.) varieties: 'Finola' (FIN-314)', 'Earlina 8FC', and 'Secuieni Jubileu', and cold and hot pressed oils were prepared from each seed. The seeds were examined for moisture content, granulometric distribution, bulk density, and fat content. Seeds were pressed without and with preconditioning (60 °C), and oil yield and pressing time were recorded. The oil was filtered through cellulose membranes. Oil-water content, oil color, fatty acid profile, and sterol content were studied. From the study conducted, there are significant differences in the parameters of oil recovery and its quality compared to 'Finola' seed oil, which is widely reported in the literature. 'Finola' oil yield was the lowest, with an average of 79% compared to 'Earlina' (82%) and 'S. Jubileu' (84%). All oil samples contained a comparable amount of sterols, with campesterol (0.32 mg/g), β-sitosterol (1.3 mg/g) and Δ5-avenasterol (0.15 mg/g) predominating. From the organoleptic evaluation, it was evident that both varieties hemp oils and marc ('Earlina' and 'S. Jubileu') were not bitter like the "Finola" oil and marc. More detailed studies in this direction have to be undertaken.

Evaluation of Mutton Quality Characteristics of Dongxiang Tribute Sheep Based on Membership Function and Gas Chromatography and Ion Mobility Spectrometry

Dongxiang tribute sheep have a history of use in food dishes such as "Dongxiang Handgrip," which dates back hundreds of years and is a favorite halal food in northwestern China. However, little is known about the mutton quality characteristics of Dongxiang tribute sheep. Here, we measured the sensory characteristics, nutritional quality, and flavor substances to comprehensively evaluate the mutton quality characteristics of these sheep. The mutton qualities of Dongxiang tribute, Tibetan, Ujumqin, and Hu sheep were comprehensively evaluated by membership function. Subsequently, the volatile components in mutton samples from 30 Dongxiang tribute sheep were detected via gas chromatography and ion mobility spectrometry (GC-IMS), and their fingerprints were established. The result of meat quality revealed that the shear force, the contents of protein, essential amino acid (EAA), non-essential amino acid (NEAA), and n-6/n-3 ratio of Dongxiang tribute mutton were better than the other three breeds. Membership functions were calculated for 10 physical and chemical indexes of mutton quality, and the comprehensive membership function values of the four breeds in order of highest to lowest mutton quality were Tibetan sheep (0.76) > Dongxiang tribute sheep (0.49) > Hu sheep (0.46) > Ujumqin sheep (0.33). Thirty volatile compounds were identified via GC-IMS: seven alcohols, eight aldehydes, five ketones, two esters, two phenols, one ether, one furan, one acid, two hydrocarbons, and one pyrazine. Ketones, aldehydes, and alcohols were the main volatile compounds forming the flavor of Dongxiang tribute sheep mutton. The reliability of the results was validated by PCA (principal component analysis) and similarity analyses. Our results provide reference value for consumers of mutton in China.

Mediterranean Diet: A Tool to Break the Relationship of Atrial Fibrillation with the Metabolic Syndrome and Non-Alcoholic Fatty Liver Disease

Atrial fibrillation (AF) is the most common supraventricular arrhythmia associated with increased cardiovascular and non-cardiovascular morbidity and mortality. As multiple factors may predispose the onset of AF, the prevention of the occurrence, recurrence and complications of this arrhythmia is still challenging. In particular, a high prevalence of cardio-metabolic comorbidities such as the metabolic syndrome (MetS) and in its hepatic manifestation, the non-alcoholic fatty liver disease (NAFLD), have been described in the AF population. A common pathogenetic mechanism linking AF, MetS and NAFLD is represented by oxidative stress. For this reason, in the past decades, numerous studies have investigated the effect of different foods/nutrients with antioxidant properties for the prevention of, and their therapeutic role is still unclear. In this narrative comprehensive review, we will summarize current evidence on (1) the association between AF, MetS and NAFLD (2) the antioxidant role of Mediterranean Diet and its components for the prevention of AF and (3) the effects of Mediterranean Diet on MetS components and NAFLD.

Is there an 'ideal' diet for patients with NAFLD?

Nonalcoholic fatty liver disease (NAFLD) is a growing epidemic that encompasses three distinct clinical phenotypes: uncomplicated fatty liver, nonalcoholic steatohepatitis (NASH) and NASH-related cirrhosis with its complications, including hepatocellular carcinoma. To date, no pharmacological treatments have been approved and lifestyle modifications including reduced caloric intake targeting a 7%-10% weight loss from baseline assessment represent the standard approach. Mediterranean diet has been recommended as the best dietary pattern since it is easy to follow and, independently of caloric intake its nutritional components have beneficial metabolic effects that not only improve steatosis but also risk factors for cardiovascular events, the leading cause of morbidity/mortality in individuals with NAFLD. Other dietary patterns such as ketogenic diet and Dietary Approach to Stop Hypertension (DASH) diet can be used in patients with NAFLD. Recently, intermittent fasting diets have gained popularity among healthy individuals and have been proposed as a safe and effective treatment for the metabolic syndrome in experimental and in a few human studies. In this narrative review, we aim to summarize the evidence for the available dietary approaches for patients with NAFLD.

Nutritional Impact on Metabolic Homeostasis and Brain Health

Aging in modern societies is often associated with various diseases including metabolic and neurodegenerative disorders. In recent years, researchers have shown that both dysfunctions are related to each other. Although the relationship is not fully understood, recent evidence indicate that metabolic control plays a determinant role in neural defects onset. Indeed, energy balance dysregulation affects neuroenergetics by altering energy supply and thus neuronal activity. Consistently, different diets to help control body weight, blood glucose or insulin sensitivity are also effective in improving neurodegenerative disorders, dampening symptoms, or decreasing the risk of disease onset. Moreover, adapted nutritional recommendations improve learning, memory, and mood in healthy subjects as well. Interestingly, adjusted carbohydrate content of meals is the most efficient for both brain function and metabolic regulation improvement. Notably, documented neurological disorders impacted by specific diets suggest that the processes involved are inflammation, mitochondrial function and redox balance as well as ATP production. Interestingly, processes involving inflammation, mitochondrial function and redox balance as well as ATP production are also described in brain regulation of energy homeostasis. Therefore, it is likely that changes in brain function induced by diets can affect brain control of energy homeostasis and other brain functions such as memory, anxiety, social behavior, or motor skills. Moreover, a defect in energy supply could participate to the development of neurodegenerative disorders. Among the possible processes involved, the role of ketone bodies metabolism, neurogenesis and synaptic plasticity, oxidative stress and inflammation or epigenetic regulations as well as gut-brain axis and SCFA have been proposed in the literature. Therefore, the goal of this review is to provide hints about how nutritional studies could help to better understand the tight relationship between metabolic balance, brain activity and aging. Altogether, diets that help maintaining a metabolic balance could be key to both maintain energy homeostasis and prevent neurological disorders, thus contributing to promote healthy aging.

Serum Levels of Free Fatty Acids in Obese Mice and Their Associations with Routine Lipid Profiles

PURPOSE

To investigate serum levels of free fatty acids (FFAs) and their associations with routine serum lipids in diet-induced obese mice, which have been scantily reported before.

METHODS

Male C57BL/6 J mice were fed high-fat diets for 12 weeks to induce obesity. Levels of serum FFAs were measured by ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry.

RESULTS

Obese mice had higher serum levels of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C), but lower triglycerides (TG) than control mice. A total of 30 FFAs were found, and 3 saturated fatty acids (SFAs), all 8 monounsaturated fatty acids (MUFAs) and 7 polyunsaturated fatty acids (PUFAs) decreased in obese mice, but one SFA (C4:0) increased. Differences in the relative levels of individual FFAs to total FFAs, SFAs, MUFAs or PUFAs between obese and control mice were different from each other and from those evaluated by concrete levels except C4:0, C16:1, C19:1 and C18:4. Only the concrete levels of C4:0, C22:3 and C18:4 were associated with routine serum lipids, including C22:3 negatively with TG in control mice, and C4:0 and C18:4 positively with LDL-C in obese mice, although the relative levels of C4:0 to total MUFAs negatively with TC, and C23:3 to total SFAs or MUFAs negatively with TG in control mice. Different relative levels of the remaining FFAs were differently associated with different routine serum lipids in obese and/or control mice.

CONCLUSION

Obesity may influence serum FFAs profiles. The relationship of individual FFAs and their relative levels to other FFAs with routine serum lipids in obese and control mice suggests that individual FFAs may interact with others and obesity on levels of routine serum lipids. Once confirmed, the interactions may be novel perspectives when fatty acids are used to improve hyperlipidemia in the subjects with obesity.

Nonalcoholic Fatty Liver Disease in Children

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide. It represents a spectrum of disease from simple hepatic steatosis to steatohepatitis that may develop into progressive hepatic fibrosis and even cirrhosis. NAFLD is the most rapidly increasing indication for liver transplantation in adults. In children, the incidence of NAFLD has also increased over the past decade. Although the majority of children with NAFLD are overweight or obese, there is an increasing subset of children with normal body mass index with so-called lean NAFLD. NAFLD in children is associated with several extrahepatic manifestations, including hyperlipidemia, insulin resistance, and obstructive sleep apnea. The pathogenesis of NAFLD in children involves a multifactorial interaction among genetics, in utero exposures, early childhood exposures, and ongoing nutritional exposures. Although there are some similarities between pediatric NAFLD and adult NAFLD, liver biopsies in children show histologic differences between the two. The current standard-of-care treatment of NAFLD in children is lifestyle change to decrease caloric intake and increase physical activity. There are no medications currently approved for the treatment of NAFLD in children. This article aims to summarize the current understanding of pediatric NAFLD and future directions for intervention and therapeutic aims.

Impact of Genetic Polymorphism on Response to Therapy in Non-Alcoholic Fatty Liver Disease

In the last decades, the global prevalence of non-alcoholic fatty liver disease (NAFLD) has reached pandemic proportions with derived major health and socioeconomic consequences; this tendency is expected to be further aggravated in the coming years. Obesity, insulin resistance/type 2 diabetes mellitus, sedentary lifestyle, increased caloric intake and genetic predisposition constitute the main risk factors associated with the development and progression of the disease. Importantly, the interaction between the inherited genetic background and some unhealthy dietary patterns has been postulated to have an essential role in the pathogenesis of NAFLD. Weight loss through lifestyle modifications is considered the cornerstone of the treatment for NAFLD and the inter-individual variability in the response to some dietary approaches may be conditioned by the presence of different single nucleotide polymorphisms. In this review, we summarize the current evidence on the influence of the association between genetic susceptibility and dietary habits in NAFLD pathophysiology, as well as the role of gene polymorphism in the response to lifestyle interventions and the potential interaction between nutritional genomics and other emerging therapies for NAFLD, such as bariatric surgery and several pharmacologic agents.

N-3 Polyunsaturated Fatty Acids and Their Lipid Mediators as A Potential Immune-Nutritional Intervention: A Molecular and Clinical View in Hepatic Disease and Other Non-Communicable Illnesses

In recent years, the beneficial effect of n-3 polyunsaturated fatty acids (n-3 PUFAs) intake on human health has been widely accepted in the field of immunonutrition. Today, we find a diversity of supplements based on n-3 PUFAs and/or minerals, vitamins and other substances. The main objective of this review is to discuss the importance of n-3 PUFAs and their derivatives on immunity and inflammatory status related to liver disease and other non-communicable illnesses. Based on the burden of liver diseases in 2019, more than two million people die from liver pathologies per year worldwide, because it is the organ most exposed to agents such as viruses, toxins and medications. Consequently, research conducted on n-3 PUFAs for liver disease has been gaining prominence with encouraging results, given that these fatty acids have anti-inflammatory and cytoprotective effects. In addition, it has been described that n-3 PUFAs are converted into a novel species of lipid intermediaries, specialized pro-resolving mediators (SPMs). At specific levels, SPMs improve the termination of inflammation as well as the repairing and regeneration of tissues, but they are deregulated in liver disease. Since evidence is still insufficient to carry out pharmacological trials to benefit the resolution of acute inflammation in non-communicable diseases, there remains a call for continuing preclinical and clinical research to better understand SPM actions and outcomes.

Lipid Droplet-Associated Factors, PNPLA3, TM6SF2, and HSD17B Proteins in Hepatopancreatobiliary Cancer

Simple Summary

Aberrant lipid synthesis and reprogrammed lipid metabolism are both associated with the development and progression of pancreatic and liver cancer. Most cells store fatty acids in the form of triacylglycerols in lipid droplets. Lipid droplets are intracellular organelles that not only store neutral lipids, but also play roles as molecular messengers and signaling factors. Some cancer cells accumulate massive amount of lipid droplets. Lipid droplets and lipid droplet-associated factors are further implicated to mediate proliferation, invasion, metastasis, as well as chemotherapy resistance in several types of cancer. This review dissected recent findings on the role of several lipid droplet-associated factors, patatin-like phospholipase domain-containing 3 (PNPLA3), Transmembrane 6 superfamily member 2 (TM6SF2), and 17β-hydroxysteroid dehydrogenase (HSD17B) 11 and 13 as well as their genetic variations in hepatopancreatobiliary diseases, especially cancer.

Abstract

Pancreatic and liver cancer are leading causes of cancer deaths, and by 2030, they are projected to become the second and the third deadliest cancer respectively. Cancer metabolism, especially lipid metabolism, plays an important role in progression and metastasis of many types of cancer, including pancreatic and liver cancer. Lipid droplets are intracellular organelles that store neutral lipids, but also act as molecular messengers, and signaling factors. It is becoming increasingly evident that alterations in the regulation of lipid droplets and their associated factors influence the risk of developing not only metabolic disease but also fibrosis and cancer. In the current review article, we summarized recent findings concerning the roles of lipid droplet-associated factors, patatin-like phospholipase domain-containing 3, Transmembrane 6 superfamily member 2, and 17β-hydroxysteroid dehydrogenase 11 and 13 as well as genetic variants in pancreatic and hepatic diseases. A better understanding of cancer type- and cell type-specific roles of lipid droplet-associated factors is important for establishing new therapeutic options in the future.

Non-Alcoholic Fatty Liver Disease in Children

Background and Objectives: The prevalence of pediatric non-alcoholic fatty liver disease is increasing. A lot of new data are published regularly. Materials and Methods: Original clinical studies, review articles, and guidelines in children were searched for and the most relevant included in this review. Results: A total of 138 retrieved papers were classified into pathogenesis, epidemiology, diagnosis, and treatment. Pathogenesis is currently explained with the "multi hit hypothesis", with complex interactions of genetic and environmental factors which trigger inflammation in steatotic liver. The prevalence is rising. A diagnosis can be made with laboratory tests, imaging, and liver biopsy after the exclusion of other causes of liver steatosis. The mainstay of treatment is lifestyle modification consisting of dietary intervention and increased physical activity. The progression to liver cirrhosis can occur even in children. Conclusions: Non-alcoholic fatty liver disease in children is a part of a metabolic syndrome in the majority of patients. Due to its complex etiology and high prevalence, multidisciplinary teams, together with public health professionals, should be involved in its treatment.

Nonalcoholic fatty liver disease or metabolic dysfunction-associated fatty liver disease diagnoses and cardiovascular diseases: From epidemiology to drug approaches

BACKGROUND

A consensus of experts has proposed to replace the term nonalcoholic fatty liver disease (NAFLD), whose global prevalence is 25%, with metabolic dysfunction-associated fatty liver disease (MAFLD), to describe more appropriately the liver disease related to metabolic derangements. MAFLD is closely intertwined with type 2 diabetes, obesity, dyslipidaemia, all linked to a rise in the risk of cardiovascular disease (CVDs). Since controversy still stands on whether or not NAFLD/MAFLD raises the odds of CVD, the present review aims to evaluate the impact of NAFLD/MAFLD aetiologies on CV health and the potential correction by dietary and drug approaches.

RESULTS

Epidemiological studies indicate that NAFLD raises risk of fatal or non-fatal CVD events. NAFLD patients have a higher prevalence of arterial plaques and stiffness, coronary calcification, and endothelial dysfunction. Although genetic and environmental factors strongly contribute to NAFLD pathogenesis, a Mendelian randomization analysis indicated that the PNPLA3 genetic variant leading to NAFLD may not be causally associated with CVD risk. Among other genetic variants related to NAFLD, TM6SF2 appears to be protective, whereas MBOAT7 may favour venous thromboembolism.

CONCLUSIONS

NAFLD is correlated to a higher CVD risk which may be ameliorated by dietary interventions. This is not surprising, since new criteria defining MAFLD include other metabolic risk abnormalities fuelling development of serious adverse extrahepatic outcomes, for example CVD. The present lack of a targeted pharmacological approach makes the identification of patients with liver disease at higher CVD risk (eg diabetes, hypertension, obesity or high levels of C-reactive protein) of major clinical interest.