The effect of coffee consumption on the non-alcoholic fatty liver disease and liver fibrosis: A meta-analysis of 11 epidemiological studies.

INTRODUCTION AND OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) is a widespread chronic liver disease. It is considered a multifactorial disorder that can progress to liver fibrosis and cause a worldwide public health concern. Coffee consumption may have a protective impact on NAFLD and liver fibrosis. However, the evidence from the previous studies is inconsistent. This meta-analysis summarizes available literature. MATERIALS AND METHODS: This study comprises two meta-analyses. The first meta-analysis summarizes the effect of coffee consumption on NAFLD in those who did or did not drink coffee. The second analysis compares the risk of liver fibrosis development between NAFLD patients who did or did not drink coffee. Pooled risk ratios (RR) and confidence intervals (CI) of observational studies were estimated. RESULTS: Of the total collected 321 articles, 11 met our eligibility criteria to be included in the analysis. The risk of NAFLD among those who drank coffee compared to those who did not was significantly lower with a pooled RR value of 0.77 (95% CI 0.60-0.98). Moreover, we also found a significantly reduced risk of liver fibrosis in those who drink coffee than those who did not drink in the NAFLD patients with the relative risk (RR) of 0.68 (95% CI 0.68-0.79). CONCLUSIONS: Regular coffee consumption is significantly associated with a reduced risk of NAFLD. It is also significantly associated with decreased risk of liver fibrosis development in already diagnosed NAFLD patients. Although coffee consumption may be considered an essential preventive measure for NAFLD, this subject needs further epidemiological studies.

Spirulina supplementation in a mouse model of diet-induced liver fibrosis reduced the pro-inflammatory response of splenocytes.

Treatment of liver fibrosis is very limited as there is currently no effective anti-fibrotic therapy. Spirulina platensis (SP) is a blue-green alga that is widely supplemented in healthy foods. The objective of this study was to determine whether SP supplementation can prevent obesity-induced liver fibrosis in vivo. Male C57BL/6J mice were randomly assigned to a low-fat or a high-fat (HF)/high-sucrose/high-cholesterol diet or an HF diet supplemented with 2·5 % SP (w/w) (HF/SP) for 16 or 20 weeks. There were no significant differences in body weight, activity, energy expenditure, serum lipids or glucose tolerance between mice on HF and HF/SP diets. However, plasma alanine aminotransferase level was significantly reduced by SP at 16 weeks. Expression of fibrotic markers and trichrome stains showed no differences between HF and HF/SP. Splenocytes isolated from HF/SP fed mice had lower inflammatory gene expression and cytokine secretion compared with splenocytes from HF-fed mice. SP supplementation did not attenuate HF-induced liver fibrosis. However, the expression and secretion of inflammatory genes in splenocytes were significantly reduced by SP supplementation, demonstrating the anti-inflammatory effects of SP in vivo. Although SP did not show appreciable effect on the prevention of liver fibrosis in this mouse model, it may be beneficial for other inflammatory conditions.

Dietary determinants of hepatic fat content and insulin resistance in overweight/obese children: a cross-sectional analysis of the Prevention of Diabetes in Kids (PREDIKID) study.

Paediatric non-alcoholic fatty liver disease has increased in parallel with childhood obesity. Dietary habits, particularly products rich in sugars, may influence both hepatic fat and insulin resistance (homeostatic model assessment for insulin resistance (HOMA-IR)). The aim of the study was to examine the association of the consumption of foods and food components, dairy desserts and substitutes (DDS), sugar-sweetened beverages (SSB), as well as total and added sugars, with hepatic fat and HOMA-IR. Dietary intake (two non-consecutive 24 h-recalls), hepatic fat (MRI) and HOMA-IR were assessed in 110 overweight/obese children (10·6 (sd 1·1) years old). Linear regression analyses were used to examine the association of dietary intake with hepatic fat and HOMA-IR adjusted for potential confounders (sex, age, energy intake, maternal educational level, total and abdominal adiposity and sugar intake). The results showed that there was a negative association between cereal intake and hepatic fat (ß=-0·197, P<0·05). In contrast, both SSB consumption (ß=0·217; P=0·028) and sugar in SSB (ß=0·210, P=0·035), but not DDS or sugar in DDS or other dietary components, were positively associated with hepatic fat regardless of potential confounders including total sugar intake. In conclusion, cereal intake might decrease hepatic fat, whereas SSB consumption and its sugar content may increase the likelihood of having hepatic steatosis. Although these observations need to be confirmed using experimental evidence, these results suggest that healthy lifestyle intervention programs are needed to improve dietary habits as well as to increase the awareness of the detrimental effects of SSB consumption early in life.

Interplay between early-life malnutrition, epigenetic modulation of the immune function and liver diseases.

Early-life nutrition plays a critical role in fetal growth and development. Food intake absence and excess are the two main types of energy malnutrition that predispose to the appearance of diseases in adulthood, according to the hypothesis of 'developmental origins of health and disease'. Epidemiological data have shown an association between early-life malnutrition and the metabolic syndrome in later life. Evidence has also demonstrated that nutrition during this period of life can affect the development of the immune system through epigenetic mechanisms. Thus, epigenetics has an essential role in the complex interplay between environmental factors and genetics. Altogether, this leads to the inflammatory response that is commonly seen in non-alcoholic fatty liver disease (NAFLD), the hepatic manifestation of the metabolic syndrome. In conjunction, DNA methylation, covalent modification of histones and the expression of non-coding RNA are the epigenetic phenomena that affect inflammatory processes in the context of NAFLD. Here, we highlight current understanding of the mechanisms underlying developmental programming of NAFLD linked to epigenetic modulation of the immune system and environmental factors, such as malnutrition.

Soya protein ß-conglycinin ameliorates fatty liver and obesity in diet-induced obese mice through the down-regulation of PPARγ.

Diets high in fat can result in obesity and non-alcoholic fatty liver disease (NAFLD). The improvement of obesity and NAFLD is an important issue. ß-Conglycinin, one of the soya proteins, is known to prevent hyperlipidaemia, obesity and NAFLD. Therefore, we aimed to investigate the effects of ß-conglycinin on the improvement of obesity and NAFLD in high-fat (HF) diet-induced obese (DIO) mice and clarify the mechanism underlying these effects in liver and white adipose tissue (WAT). DIO male ddY mice were divided into six groups: HF, medium-fat (MF) and low-fat (LF) groups fed casein, and HF, MF and LF groups in all of which the casein was replaced by ß-conglycinin. A period of 5 weeks later, the ß-conglycinin-supplemented group resulted in lower body weight, relative weight of subcutaneous WAT, and hepatic TAG content (P=0·001). Furthermore, ß-conglycinin suppressed the hepatic expression of Pparγ2 in the HF dietary group, sterol regulatory element-binding protein-1c and the target genes. The expressions of inflammation-related genes were significantly low in the epididymal and subcutaneous WAT from the mice fed ß-conglycinin compared with those fed casein in the HF dietary group. Moreover, the expressions of Pparγ1 and Pparγ2 mRNA were suppressed in subcutaneous WAT in the HF dietary group but not in epididymal WAT. The concentrations of insulin and leptin were low in the serum of the mice fed ß-conglycinin. In conclusion, ß-conglycinin effectively improved obesity and NAFLD in DIO mice, and it appears to be a promising dietary protein for the amelioration of NAFLD and obesity.

Improvements in clinical characteristics of patients with non-alcoholic fatty liver disease, after an intervention based on the Mediterranean lifestyle: a randomised controlled clinical trial.

Lifestyle interventions remain the cornerstone therapy for non-alcoholic fatty liver disease (NAFLD). This randomised controlled single-blind clinical trial investigated the effect of Mediterranean diet (MD) or Mediterranean lifestyle, along with weight loss, in NAFLD patients. In all, sixty-three overweight/obese patients (50 (sd 11) years, BMI=31·8 (sd 4·5) kg/m2, 68 % men) with ultrasonography-proven NAFLD (and elevated alanine aminotransferase (ALT) and/or γ-glutamyl transpeptidase (GGT) levels) were randomised to the following groups: (A) control group (CG), (B) Mediterranean diet group (MDG) or (C) Mediterranean lifestyle group (MLG). Participants of MDG and MLG attended seven 60-min group sessions for 6 months, aiming at weight loss and increasing adherence to MD. In the MLG, additional guidance for increasing physical activity and improving sleep habits were given. Patients in CG received only written information for a healthy lifestyle. At the end of 6 months, 88·8 % of participants completed the study. On the basis of intention-to-treat analysis, both MDG and MLG showed greater weight reduction and higher adherence to MD compared with the CG (all P<0·05) at the end of intervention. In addition, MLG increased vigorous exercise compared with the other two study groups (P<0·001) and mid-day rest/naps compared with CG (P=0·04). MLG showed significant improvements in ALT levels (i.e. ALT<40 U/l (P=0·03) and 50 % reduction of ALT levels (P=0·009)) and liver stiffness (P=0·004) compared with CG after adjusting for % weight loss and baseline values. MDG improved only liver stiffness compared with CG (P<0·001) after adjusting for the aforementioned variables. Small changes towards the Mediterranean lifestyle, along with weight loss, can be a treatment option for patients with NAFLD.

20-Week follow-up of hepatic steatosis installation and liver mitochondrial structure and activity and their interrelation in rats fed a high-fat-high-fructose diet.

The incidence of obesity and its metabolic complications are rapidly increasing and become a major public health issue. This trend is associated with an increase in the prevalence of non-alcoholic fatty liver disease (NAFLD), insulin resistance and diabetes. The sequence of events leading to NAFLD progression and mitochondrial dysfunction and their interrelation remains to be elucidated. This study aimed to explore the installation and progression of NAFLD and its association with the liver mitochondrial structure and activity changes in rats fed an obesogenic diet up to 20 weeks. Male Wistar rats were fed either a standard or high-fat-high-fructose (HFHFR) diet and killed on 4, 8, 12, 16 and 20 weeks of diet intake. Rats fed the HFHFR diet developed mildly overweight, associated with increased adipose tissue weight, hepatic steatosis, hyperglycaemia and hyperinsulinaemia after 8 weeks of HFHFR diet. Hepatic steatosis and many biochemical modifications plateaued at 8-12 weeks of HFHFR diet with slight amelioration afterwards. Interestingly, several biochemical and physiological parameters of mitochondrial function, as well as its phospholipid composition, in particular cardiolipin content, were tightly related to hepatic steatosis installation. These results showed once again the interrelation between hepatic steatosis development and mitochondrial activity alterations without being able to say whether the mitochondrial alterations preceded or followed the installation/progression of hepatic steatosis. Because both hepatic steatosis and mitochondrial alterations occurred as early as 4 weeks of diet, future studies should consider these four 1st weeks to reveal the exact interconnection between these major consequences of obesogenic diet intake.

Suppressive effect of nobiletin and epicatechin gallate on fructose uptake in human intestinal epithelial Caco-2 cells.

Inhibition of excessive fructose intake in the small intestine could alleviate fructose-induced diseases such as hypertension and non-alcoholic fatty liver disease. We examined the effect of phytochemicals on fructose uptake using human intestinal epithelial-like Caco-2 cells which express the fructose transporter, GLUT5. Among 35 phytochemicals tested, five, including nobiletin and epicatechin gallate (ECg), markedly inhibited fructose uptake. Nobiletin and ECg also inhibited the uptake of glucose but not of L-leucine or Gly-Sar, suggesting an inhibitory effect specific to monosaccharide transporters. Kinetic analysis further suggested that this reduction in fructose uptake was associated with a decrease in the apparent number of cell-surface GLUT5 molecules, and not with a change in the affinity of GLUT5 for fructose. Lastly, nobiletin and ECg suppressed the permeation of fructose across Caco-2 cell monolayers. These findings suggest that nobiletin and ECg are good candidates for preventing diseases caused by excessive fructose intake.

Synbiotic supplementation in lean patients with non-alcoholic fatty liver disease: a pilot, randomised, double-blind, placebo-controlled, clinical trial.

Although non-alcoholic fatty liver disease (NAFLD) is the leading aetiology of liver disorders in the world, there is no proven treatment for NAFLD patients with normal or low BMI. The aim of this study was to evaluate the efficacy of synbiotics supplementation in NAFLD patients with normal or low BMI. In this randomised, double-blind, placebo-controlled, clinical trial, fifty patients with NAFLD were assigned to take either a synbiotic supplement or a placebo capsule for 28 weeks. Both groups were advised to follow a healthy lifestyle. At the end of the study, hepatic steatosis and fibrosis reduced in both groups; however, the mean reduction was significantly greater in the synbiotic group rather than in the placebo group (P<0·001). Furthermore, serum levels of fasting blood sugar, TAG and most of the inflammatory mediators reduced in the synbiotic group significantly compared with the placebo group (P<0·05). Our results provide evidence that synbiotic supplementation improves the main features of NAFLD in patients with normal and low BMI, at least partially through reduction in inflammatory indices. Further studies are needed to address the exact mechanism of action of these effects.

Citrulline decreases hepatic endotoxin-induced injury in fructose-induced non-alcoholic liver disease: an ex vivo study in the isolated perfused rat liver.

Steatosis can sensitise the liver to various challenges and favour the development of non-alcoholic fatty liver disease (NAFLD). In this context, fructose feeding promotes endotoxin translocation from the gut, contributing to disease progression via an inflammatory process. Citrulline is protective against fructose-induced NAFLD; we hypothesised that this property might be related to its anti-inflammatory and antioxidative action against endotoxin-induced hepatic injuries. This hypothesis was evaluated in a model of perfused liver isolated from NAFLD rats. Male Sprague-Dawley rats (n 30) were fed either a standard rodent chow or a 60 % fructose diet alone, or supplemented with citrulline (1 g/kg per d) for 4 weeks. After an evaluation of their metabolic status, fasted rats received an intraperitoneal injection of lipopolysaccharide (LPS) (2·5 mg/kg). After 1 h, the livers were isolated and perfused for 1 h to study liver function and metabolism, inflammation and oxidative status. In vivo, citrulline significantly decreased dyslipidaemia induced by a high-fructose diet and insulin resistance. In the isolated perfused rat livers, endotoxaemia resulted in higher cytolysis (alanine aminotransferase release) and higher inflammation (Toll-like receptor 4) in livers of fructose-fed rats, and it was prevented by citrulline supplementation. Oxidative stress and antioxidative defences were similar in all three groups. Amino acid exchanges and metabolism (ammonia and urea release) were only slightly different between the three groups. In this context of mild steatosis, our results suggest that fructose-induced NAFLD leads to an increased hepatic sensitivity to LPS-induced inflammation. Citrulline-induced restriction of the inflammatory process may thus contribute to the prevention of NAFLD.

Current and future strategies for the nutritional management of cardiometabolic complications of androgen deprivation therapy for prostate cancer.

Androgen deprivation therapy (ADT) is used widely as part of a combined modality for the treatment of prostate cancer. However, ADT has also been associated with the development of cardiometabolic complications that can increase mortality from cardiovascular events. There is emerging evidence to suggest that ADT-related cardiometabolic risk can be mitigated by diet and lifestyle modification. While the clinical focus for a nutritional approach for achieving this effect is unclear, it may depend upon the timely assessment and targeting of dietary changes to the specific risk phenotype of the patient. The present review aims to address the metabolic origins of ADT-related cardiometabolic risk, existing evidence for the effects of dietary intervention in modifying this risk, and the priorities for future dietary strategies.

Metabolic consequences of obesity and insulin resistance in polycystic ovary syndrome: diagnostic and methodological challenges.

Women with polycystic ovary syndrome (PCOS) have a considerable risk of metabolic dysfunction. This review aims to present contemporary knowledge on obesity, insulin resistance and PCOS with emphasis on the diagnostic and methodological challenges encountered in research and clinical practice. Variable diagnostic criteria for PCOS and associated phenotypes are frequently published. Targeted searches were conducted to identify all available data concerning the association of obesity and insulin resistance with PCOS up to September 2016. Articles were considered if they were peer reviewed, in English and included women with PCOS. Obesity is more prevalent in women with PCOS, but studies rarely reported accurate assessments of adiposity, nor split the study population by PCOS phenotypes. Many women with PCOS have insulin resistance, though there is considerable variation reported in part due to not distinguishing subgroups known to have an impact on insulin resistance as well as limited methodology to measure insulin resistance. Inflammatory markers are positively correlated with androgen levels, but detailed interactions need to be identified. Weight management is the primary therapy; specific advice to reduce the glycaemic load of the diet and reduce the intake of pro-inflammatory SFA and advanced glycation endproducts have provided promising results. It is important that women with PCOS are educated about their increased risk of metabolic complications in order to make timely and appropriate lifestyle modifications. Furthermore, well-designed robust studies are needed to evaluate the mechanisms behind the improvements observed with dietary interventions.

Similarities and interactions between the ageing process and high chronic intake of added sugars.

In our societies, the proportions of elderly people and of obese individuals are increasing. Both factors are associated with high health-related costs. During obesity, many authors suggest that it is a high chronic intake of added sugars (HCIAS) that triggers the shift towards pathology. However, the majority of studies were performed in young subjects and only a few were interested in the interaction with the ageing process. Our purpose was to discuss the metabolic effects of HCIAS, compare with the effects of ageing, and evaluate how deleterious the combined action of HCIAS and ageing could be. This effect of HCIAS seems mediated by fructose, targeting the liver first, which may lead to all subsequent metabolic alterations. The first basic alterations induced by fructose are increased oxidative stress, protein glycation, inflammation, dyslipidaemia and insulin resistance. These alterations are also present during the ageing process, and are closely related to each other, one leading to the other. These basic alterations are also involved in more complex syndromes, which are also favoured by HCIAS, and present during ageing. These include non-alcoholic fatty liver disease, hypertension, neurodegenerative diseases, sarcopenia and osteoporosis. Cumulative effects of ageing and HCIAS have been seldom tested and may not always be strictly additive. Data also suggest that some of the metabolic alterations that are more prevalent during ageing could be related more with nutritional habits than to intrinsic ageing. In conclusion, it is clear that HCIAS interacts with the ageing process, accelerates the accumulation of metabolic alterations, and that it should be avoided.

Meta-Analysis of Randomized Controlled Trials of Pharmacologic Agents in Non-alcoholic Steatohepatitis.

BACKGROUND: Currently, there is no standardized treatment regimen for non-alcoholic steatohepatitis. AIM: We performed a metaanalysis of high quality randomized controlled trials that evaluated treatment response to metformin, thiazolidinediones (TZDs), and vitamin E in adult patients with non-alcoholic steatohepatitis. Outcome measures were improvement in liver histology, biochemical, and anthropometric measures. MATERIAL AND METHODS: Nine trials met inclusion criteria (3 with TZD, 3 with Metformin, 2 with Vitamin E and 1 with both TZD and Vitamin E.). RESULTS: With metformin, weighted liver histologic scores for steatosis, ballooning, and fibrosis did not demonstrate significant improvement and lobular inflammation worsened significantly (weighted mean increase 0.21, 95% CI 0.11 to 0.31, P < 0.0001). The liver histology score including steatosis (OR 3.51, 95% CI 2.14 to 5.78) and lobular inflammation (OR 2.65, 95% CI 1.69 to 4.15) improved with TZDs. Hepatic fibrosis (OR 1.58, 95% CI 0.98 to 2.54) and ballooning scores (OR 1.84, 95% CI 0.94 to 3.58) did not demonstrate significant improvement. With Vitamin E, weighted liver histologic scores for steatosis (weighted mean decrease -0.60, 95% CI -0.85 to -0.35, P < 0.0001), lobular inflammation (weighted mean decrease - 0.40, 95% CI -0.61 to -0.20, P = 0.0001) and ballooning (weighted mean decrease -0.30, 95% CI -0.54 to -0.07, P = 0.01) demonstrated significant improvement compared to placebo. Fibrosis did not significantly change. CONCLUSION: In patients with NASH, TZDs and Vitamin E improve liver histologic scores but metformin does not. Insulin resistance also improves with both TZDs and metformin. Fibrosis does not improve with any of the agents.

Healthy dietary pattern is inversely associated with non-alcoholic fatty liver disease in elderly.

The prevalence of non-alcoholic fatty liver disease (NAFLD) is rising, an increase that may be associated with changes in lifestyle such as unhealthy dietary patterns. Although advanced age is a risk factor for NAFLD, no studies reporting this association in the elderly population were found. In the present study, the association between dietary patterns and NAFLD in the elderly was assessed. A study including 229 older adults was conducted. NAFLD diagnosis was defined as individuals whose ultrasound examination disclosed hepatic steatosis at any stage, in the absence of excess intake of alcoholic beverages. Dietary patterns were obtained by principal components analysis. Mean scores and standard errors of each dietary pattern were calculated for the groups with and without NAFLD, and mean scores of the two groups were compared using the Mann-Whitney U test. The prevalence ratios and 95 % CI were estimated for each tertile of the dietary pattern adherence scores using Poisson multiple regression models with robust variance. A total of 103 (45 %) elderly with NAFLD and four dietary patterns were identified: traditional, regional snacks, energy dense and healthy. Mean scores for adherence to the healthy pattern in the groups with and without NAFLD differed. NAFLD was inversely associated with greater adherence to the healthy pattern and directly associated with the regional snacks, after adjustment for confounders. In conclusion, healthy dietary pattern is inversely associated with NAFLD in elderly.

High serum carotenoids are associated with lower risk for developing elevated serum alanine aminotransferase among Japanese subjects: the Mikkabi cohort study.

Many recent studies have shown that antioxidant vitamins and/or carotenoids may reduce liver disease, but this association has not been well established with thorough longitudinal cohort studies. The objective of this study was to longitudinally investigate whether serum carotenoids at baseline are associated with the risk of developing elevated serum alanine aminotransferase (ALT) among Japanese subjects. We conducted a follow-up study of 1073 males and females aged between 30 and 79 years at baseline from the Mikkabi prospective cohort study. Those who participated in the baseline study and completed follow-up surveys were examined longitudinally. Exclusions included excessive alcohol consumption (≥60 g alcohol/d), hepatitis B and C and having a history of medication use for liver disease. A cohort of 213 males and 574 females free of elevated serum ALT (>30 IU/ml) at baseline was studied. Over a mean follow-up period of 7·4 (sd 3·1) years, thirty-one males and forty-nine females developed new elevated serum ALT. After adjustments for confounders, the hazard ratios for elevated serum ALT in the highest tertiles of basal serum ß-carotene, ß-cryptoxanthin and total provitamin A carotenoids against the lowest tertiles were 0·43 (95 % CI 0·22, 0·81), 0·51 (CI 0·27, 0·94) and 0·52 (CI 0·28, 0·97), respectively. For α-carotene and lycopene, borderline reduced risks were also observed; however, these were not significant. Our results further support the hypothesis that antioxidant carotenoids, especially provitamin A carotenoids, might help prevent earlier pathogenesis of non-alcoholic liver disease in Japanese subjects.

Dietary sodium and potassium intake in relation to non-alcoholic fatty liver disease.

A few epidemiological data are available assessing the associations of intakes of sodium (Na) and potassium (K) with non-alcoholic fatty liver disease (NAFLD). We aimed to examine the associations of dietary intake of Na and K with the prevalence of ultrasound-diagnosed NAFLD. We performed a cross-sectional study of 100 177 participants (46 596 men and 53 581 women) who underwent a health screening examination and completed a FFQ at the Kangbuk Samsung Hospital Total Healthcare Centers, South Korea, between 2011 and 2013. NAFLD was defined by ultrasonographic detection of fatty liver in the absence of excessive alcohol intake or other known causes of liver disease. The proportion of NAFLD was 35·6 % for men and 9·8 % for women. Increasing prevalence of NAFLD was observed with increasing Na intake. The multivariable-adjusted prevalence ratios (PR) of NAFLD comparing the highest with the lowest quintile of energy-adjusted Na intake were 1·25 (95 % CI 1·18, 1·32; P trend<0·001) in men and 1·32 (95 % CI 1·18, 1·47; P trend <0·001) in women. However, when we additionally adjusted for body fat percentage, the association became attenuated; the corresponding PR of NAFLD were 1·15 (95 % CI 1·09, 1·21) in men and 1·06 (95 % CI 0·95, 1·17) in women. No inverse association was observed for energy-adjusted K intake. Our findings suggest that higher Na intake is associated with a greater prevalence of NAFLD in young and middle-aged asymptomatic adults, which might be partly mediated by adiposity.

Differences in metabolic biomarkers in the blood and gene expression profiles of peripheral blood mononuclear cells among normal weight, mildly obese and moderately obese subjects.

We compared metabolic biomarkers in the blood and peripheral blood mononuclear cell (PBMC) gene expression profiles among normal weight (BMI, 18·5-23 kg/m2), mildly obese (BMI, 25-27·5 kg/m2) and moderately obese Korean adult men (BMI, 27·5-30 kg/m2). High leptin, lipids (except LDL- and HDL-cholesterol) and apoB levels and low adiponectin and HDL-cholesterol levels were present in the plasma of both mildly and moderately obese subjects. Circulating levels of inflammatory cytokines and markers of insulin resistance, oxidative stress and liver damage were altered in moderately obese subjects but not in mildly obese subjects. PBMC transcriptome data showed enrichment of pathways involved in energy metabolism, insulin resistance, bone metabolism, cancer, inflammation and fibrosis in both mildly and moderately obese subjects. Signalling pathways involved in oxidative phosphorylation, TAG synthesis, carbohydrate metabolism and insulin production; mammalian target of rapamycin, forkhead box O, ras-proximate-1, RAS and transforming growth factor-ß signalling; as well as extracellular matrix-receptor interaction were enriched only in moderately obese subjects, indicating that changes in PBMC gene expression profiles, according to metabolic disturbances, were associated with the development and/or aggravation of obesity. In particular, fourteen and fifteen genes differentially expressed only in mildly obese subjects and in both mildly and moderately obese subjects, respectively, could be used as early or stable biomarkers for diagnosing and treating obesity-associated metabolic disturbance. We characterised BMI-associated metabolic and molecular biomarkers in the blood and provided clues about potential blood-based targets for preventing or treating obesity-related complications.

Low vitamin D levels and non-alcoholic fatty liver disease, evidence for their independent association in men in East China: a cross-sectional study (Survey on Prevalence in East China for Metabolic Diseases and Risk Factors (SPECT-China)).

Recent studies have suggested an association between vitamin D and non-alcoholic fatty liver disease (NAFLD); however, some results are subject to debate. This study was carried out to evaluate the correlation between NAFLD and vitamin D in men and women in East China. The data were obtained from a cross-sectional study that focused on the health and metabolic status of adults in sixteen areas of East China. According to ultrasonic assessments, the patients were divided into normal and NAFLD groups. Demographic characteristics and biochemical measurements were obtained. Binary logistic regression analysis was used to explore the association. In total, 5066 subjects were enrolled, and 2193 (43·3 %) were diagnosed with NAFLD; 84·56 % of the subjects showed vitamin D deficiency. Subjects with high vitamin D levels had a lower prevalence of NAFLD, particularly male subjects. Within the highest quartile of vitamin D levels, the prevalence of NAFLD was 40·8 %, whereas the lowest quartile of vitamin D levels showed a prevalence of 62·2 %, which was unchanged in women across the vitamin D levels. Binary logistic analysis showed that decreased vitamin D levels were associated with an increased risk of NAFLD (OR 1·54; 95 % CI 1·26, 1·88). This study suggests that vitamin D levels are significantly associated with NAFLD and that vitamin D acts as an independent factor for NAFLD prevalence, particularly in males in East China. Vitamin D interventional treatment might be a new target for controlling NAFLD; elucidating the mechanism requires further research.

Preventive effects of citrulline on Western diet-induced non-alcoholic fatty liver disease in rats.

A Western diet induces insulin resistance, liver steatosis (non-alcoholic fatty liver disease (NAFLD)) and intestinal dysbiosis, leading to increased gut permeability and bacterial translocation, thus contributing to the progression of NAFLD to non-alcoholic steatohepatitis. In the present study, we sought, in a model of Western diet-induced NAFLD, to determine whether citrulline (Cit), an amino acid that regulates protein and energy metabolism, could decrease Western diet-induced liver injuries, as well as the mechanisms involved. Sprague-Dawley rats were fed a high-fat diet (45 %) and fructose (30 %) in drinking water or a control diet associated with water (group C) for 8 weeks. The high-fat, high-fructose diet (Western diet) was fed either alone (group WD) or with Cit (1 g/kg per d) (group WDC) or an isonitrogenous amount of non-essential amino acids (group WDA). We evaluated nutritional and metabolic status, liver function, intestinal barrier function, gut microbiota and splanchnic inflammatory status. Cit led to a lower level of hepatic TAG restricted to microvesicular lipid droplets and to a lower mRNA expression of CCAAT-enhancer-binding protein homologous protein, a marker of endoplasmic reticulum stress, of pro-inflammatory cytokines Il6 (P<0·05) and Tnfα, and of toll-like receptor 4 (Tlr4) (P<0·05). Cit also improved plasma TAG and insulin levels. In the colon, it decreased inflammation (Tnfα and Tlr4 expressions) and increased claudin-1 protein expression. This was associated with higher levels of Bacteroides/Prevotella compared with rats fed the Western diet alone. Cit improves Western diet-induced liver injuries via decreased lipid deposition, increased insulin sensitivity, lower inflammatory process and preserved antioxidant status. This may be related in part to its protective effects at the gut level.