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1.
Br J Nutr ; 121(12): 1345-1356, 2019 06.
Article in English | MEDLINE | ID: mdl-30940241

ABSTRACT

Perinatal maternal high-fat diet (HFD) increases susceptibility to obesity and fatty liver diseases in adult offspring, which can be attenuated by the potent hypolipidaemic action of fish oil (FO), an n-3 PUFA source, during adult life. Previously, we described that adolescent HFD offspring showed resistance to FO hypolipidaemic effects, although FO promoted hepatic molecular changes suggestive of reduced lipid accumulation. Here, we investigated whether this FO intervention only during the adolescence period could affect offspring metabolism in adulthood. Then, female Wistar rats received isoenergetic, standard (STD: 9 % fat) or high-fat (HFD: 28·6 % fat) diet before mating, and throughout pregnancy and lactation. After weaning, male offspring received the standard diet; and from 25 to 45 d old they received oral administration of soyabean oil or FO. At 150 d old, serum and hepatic metabolic parameters were evaluated. Maternal HFD adult offspring showed increased body weight, visceral adiposity, hyperleptinaemia and decreased hepatic pSTAT3/STAT3 ratio, suggestive of hepatic leptin resistance. FO intake only during the adolescence period reduced visceral adiposity and serum leptin, regardless of maternal diet. Maternal HFD promoted dyslipidaemia and hepatic TAG accumulation, which was correlated with reduced hepatic carnitine palmitoyl transferase-1a content, suggesting lipid oxidation impairment. FO intake did not change serum lipids; however, it restored hepatic TAG content and hepatic markers of lipid oxidation to STD offspring levels. Therefore, we concluded that FO intake exclusively during adolescence programmed STD offspring and reprogrammed HFD offspring male rats to a healthier metabolic phenotype in adult life, reducing visceral adiposity, serum leptin and hepatic TAG content in offspring adulthood.


Subject(s)
Diet, High-Fat/adverse effects , Dietary Supplements , Dyslipidemias/prevention & control , Fish Oils/administration & dosage , Prenatal Exposure Delayed Effects/prevention & control , Animals , Dyslipidemias/etiology , Fatty Acids, Omega-3/metabolism , Female , Intra-Abdominal Fat/metabolism , Leptin/blood , Liver/metabolism , Male , Maternal Nutritional Physiological Phenomena , Pregnancy , Prenatal Exposure Delayed Effects/etiology , Rats , Rats, Wistar , Triglycerides/metabolism
2.
Br J Nutr ; 121(10): 1097-1107, 2019 05.
Article in English | MEDLINE | ID: mdl-30834845

ABSTRACT

Recently there has been a considerable rise in the frequency of metabolic diseases, such as obesity, due to changes in lifestyle and resultant imbalances between energy intake and expenditure. Whey proteins are considered as potentially important components of a dietary solution to the obesity problem. However, the roles of individual whey proteins in energy balance remain poorly understood. This study investigated the effects of a high-fat diet (HFD) containing α-lactalbumin (LAB), a specific whey protein, or the non-whey protein casein (CAS), on energy balance, nutrient transporters expression and enteric microbial populations. C57BL/6J mice (n 8) were given an HFD containing either 20 % CAS or LAB as protein sources or a low-fat diet containing CAS for 10 weeks. HFD-LAB-fed mice showed a significant increase in cumulative energy intake (P=0·043), without differences in body weight, energy expenditure, locomotor activity, RER or subcutaneous and epididymal white adipose tissue weight. HFD-LAB intake led to a decrease in the expression of glut2 in the ileum (P=0·05) and in the fatty acid transporter cd36 (P<0·001) in both ileum and jejunum. This suggests a reduction in absorption efficiency within the small intestine in the HFD-LAB group. DNA from faecal samples was used for 16S rRNA-based assessment of intestinal microbiota populations; the genera Lactobacillus, Parabacteroides and Bifidobacterium were present in significantly higher proportions in the HFD-LAB group. These data indicate a possible functional relationship between gut microbiota, intestinal nutrient transporters and energy balance, with no impact on weight gain.


Subject(s)
Diet, High-Fat/adverse effects , Energy Metabolism/drug effects , Gastrointestinal Microbiome/drug effects , Lactalbumin/adverse effects , Membrane Transport Proteins/metabolism , Adiposity/drug effects , Animals , CD36 Antigens/metabolism , Caseins/adverse effects , Diet, Fat-Restricted/adverse effects , Energy Intake/drug effects , Feces/microbiology , Glucose Transporter Type 2/metabolism , Ileum/metabolism , Jejunum/metabolism , Mice , Mice, Inbred C57BL , RNA, Ribosomal, 16S/analysis , Weight Gain/drug effects
3.
Appl Microbiol Biotechnol ; 103(13): 5269-5283, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31020379

ABSTRACT

Gut microbiota play a key role in the regulation of obesity and associated metabolic disorders. To study the relationship between them, antibiotics have been widely used to generate pseudo-germ-free rodents as control models. However, it is not clear whether antibiotics impact an animal's metabolic phenotype. Therefore, the effect of antibiotics-induced gut microbial perturbations on metabolic phenotypes in high-fat diet (HFD) fed mice was investigated. The results showed that antibiotics perturbed gut microbial composition and structure. Community diversity and richness were reduced, and the phyla Firmicutes/Bacteroidetes (F/B) ratio was decreased by antibiotics. Visualization of Unifrac distance data using principal component analysis (PCA) and unweighted pair-group method with arithmetic mean (UPGAM) demonstrated that fecal samples of HFD-fed mice separated from those of chow diet (CD) fed mice. Fecal samples from antibiotics-treated and non-treated mice were clustered into two different microbial populations. Moreover, antibiotics suppressed HFD-induced metabolic features, including body weight gain (BWG), liver weight (LW), epididymal fat weight (EFW), and serum levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), alanine aminotransferase (ALT), fasting blood glucose (FBG), and insulin (INS) significantly (P < 0.05). Lachnospiraceae, Ruminiclostridium and Helicobacter, biomarkers of mouse gut microbiota before treatment by antibiotics, were positively correlated with obesity phenotypes significantly (P < 0.05) and were decreased by (92.95 ± 5.09) %, (97.73 ± 2.09) % and (99.48 ± 0.21) % respectively after 30 days of treatment by antibiotics. However, Bacteroidia were enriched in HFD-fed antibiotics-treated mice and were negatively correlated with obesity phenotypes significantly (P < 0.05). We suggested that the antibiotics-induced depletion of Lachnospiraceae, Ruminiclostridium, and Helicobacter, and the decrease in F/B ratio in gut microbiota played a role in the prevention of HFD-induced obesity in mice.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Bacteroidetes/classification , Firmicutes/classification , Gastrointestinal Microbiome/drug effects , Obesity/microbiology , Animals , Bacteroidetes/drug effects , Diet, High-Fat , Disease Models, Animal , Feces/microbiology , Firmicutes/drug effects , Male , Mice , Mice, Inbred C57BL , Phenotype
4.
Nutr Res Rev ; 32(1): 128-145, 2019 06.
Article in English | MEDLINE | ID: mdl-30707092

ABSTRACT

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.


Subject(s)
Epigenesis, Genetic , Immune System/physiology , Liver/pathology , Malnutrition/complications , Maternal Nutritional Physiological Phenomena , Non-alcoholic Fatty Liver Disease/etiology , Nutritional Status , Carcinoma, Hepatocellular/etiology , DNA Methylation , Female , Histones , Humans , Inflammation/etiology , Metabolic Syndrome/etiology , MicroRNAs , Pregnancy , Prenatal Exposure Delayed Effects
5.
Br J Nutr ; 120(7): 751-762, 2018 10.
Article in English | MEDLINE | ID: mdl-30105962

ABSTRACT

7-Hydroxymatairesinol (7-HMR) is a plant lignan abundant in various concentrations in plant foods. The objective of this study was to test HMRLignan™, a purified form of 7-HMR, and the corresponding Picea abies extract (total extract P. abies; TEP) as dietary supplements on a background of a high-fat diet (HFD)-induced metabolic syndrome in mice and in the 3T3-L1 adipogenesis model. Mice, 3 weeks old, were fed a HFD for 60 d. Subgroups were treated with 3 mg/kg body weight 7-HMR (HMRLignan™) or 10 mg/kg body weight TEP by oral administration. 7-HMR and TEP limited the increase in body weight (-11 and -13 %) and fat mass (-11 and -18 %) in the HFD-fed mice. Epididymal adipocytes were 19 and -12 % smaller and the liver was less steatotic (-62 and -65 %). Serum lipids decreased in TEP-treated mice (-11 % cholesterol, -23 % LDL and -15 % TAG) and sugar metabolism was ameliorated by both lignan preparations, as shown by a more than 70 % decrease in insulin secretion and insulin resistance. The expression of several metabolic genes was modulated by the HFD with an effect that was reversed by lignan. In 3T3-L1 cells, the 7-HMR metabolites enterolactone (ENL) and enterodiol (END) showed a 40 % inhibition of cell differentiation accompanied by the inhibited expression of the adipogenic genes PPARγ, C/EBPα and aP2. Furthermore, END and ENL caused a 10 % reduction in TAG uptake in HEPA 1-6 hepatoma cells. In conclusion, 7-HMR and TEP reduce metabolic imbalances typical of the metabolic syndrome and obesity in male mice, whereas their metabolites inhibit adipogenesis and lipid uptake in vitro.


Subject(s)
Blood Glucose/metabolism , Body Weight/drug effects , Diet, High-Fat , Lignans/pharmacology , Lipid Metabolism/drug effects , Metabolic Syndrome/drug therapy , Picea/chemistry , 3T3-L1 Cells , 4-Butyrolactone/analogs & derivatives , 4-Butyrolactone/pharmacology , 4-Butyrolactone/therapeutic use , Adipogenesis/drug effects , Adipogenesis/genetics , Adipose Tissue/cytology , Adipose Tissue/drug effects , Adipose Tissue/metabolism , Animals , Anti-Obesity Agents/pharmacology , Anti-Obesity Agents/therapeutic use , Dietary Supplements , Fatty Liver/drug therapy , Fatty Liver/metabolism , Gene Expression , Insulin Resistance , Lignans/therapeutic use , Lipids/blood , Male , Metabolic Syndrome/blood , Metabolic Syndrome/etiology , Metabolic Syndrome/metabolism , Mice , Mice, Inbred C57BL , Obesity/blood , Obesity/etiology , Obesity/metabolism , Obesity/prevention & control , Plant Extracts/pharmacology , Plant Extracts/therapeutic use
6.
Br J Nutr ; 119(12): 1393-1399, 2018 06.
Article in English | MEDLINE | ID: mdl-29845904

ABSTRACT

Blueberry, rich in antioxidant and anti-inflammatory phytochemicals, has been demonstrated to lower inflammatory status in adipose induced by high-fat diet (HFD) and obesity. The effect of blueberry on systemic immune functions has not been examined. C57BL/6 mice were randomised to one of three diets - low-fat diet (LFD), HFD and HFD plus 4 % (w/w) blueberry (HFD+B) - for 8 or 12 weeks. Ex vivo T-cell mitogens (concanavalin A (Con A); phytohaemagglutinin), T-cell antibody (anti-CD3; anti-CD3/CD28)-stimulated T-cell proliferation and cytokine production were assessed. After 8 weeks, both HFD groups weighed more (>4 g) than the LFD group; after 12 weeks, HFD+B-fed mice weighed more (>6 g) and had 41 % more adipose tissue than HFD-fed mice (P<0·05). After 12 weeks, T-cell proliferation was less in both HFD groups, compared with the LFD group. HFD-associated decrements in T-cell proliferation were partially (10-50 %) prevented by blueberry supplementation. At 12 weeks, splenocytes from HFD mice, but not from HFD+B mice, produced 51 % less IL-4 (CD3/CD28) and 57 % less interferon-γ (Con A) compared with splenocytes from LFD mice (P<0·05). In response to lipopolysaccharide challenge, splenocytes from both HFD groups produced 24-30 % less IL-6 and 27-33 % less TNF-α compared with splenocytes from LFD mice (P<0·05), indicating impaired acute innate immune response. By demonstrating deleterious impacts of HFD feeding on T-cell proliferation and splenocyte immune responses, our results provide insights into how HFD/obesity can disrupt systemic immune function. The protective effects of blueberry suggest that dietary blueberry can buttress T-cell and systemic immune function against HFD-obesity-associated insults.


Subject(s)
Blueberry Plants , Dietary Supplements , Obesity/diet therapy , Obesity/immunology , T-Lymphocytes/immunology , Adiposity , Animals , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Cell Proliferation , Cytokines/biosynthesis , Diet, Fat-Restricted , Diet, High-Fat/adverse effects , Immunity, Cellular , Immunosuppressive Agents/administration & dosage , Male , Mice , Mice, Inbred C57BL , Obesity/etiology , T-Lymphocytes/pathology , Weight Gain
7.
Br J Nutr ; 120(4): 385-392, 2018 08.
Article in English | MEDLINE | ID: mdl-29925443

ABSTRACT

Specific adipokines, such as adiponectin and resistin, are secreted from adipose tissue and are associated with the development of obesity. Supplementation of dietary SCFA can prevent and reverse high-fat-diet (HFD)-induced obesity. However, it is not clear whether SCFA ameliorate abnormal expression of adiponectin and resistin in the obese state. The aim of this study was to investigate the effects of SCFA on adiponectin and resistin's expressions in diet-induced obese mice, as well as the potential mechanisms associated with DNA methylation. C57BL/6J male mice were fed for 16 weeks with five types of HFD (34·9 % fat by wt., 60 % kJ) - a control HFD and four HFD with acetate (HFD-A), propionate (HFD-P), butyrate (HFD-B) and their admixture (HFD-SCFA). Meanwhile, a low-fat diet (4·3 % fat by wt., 10 % kJ) was used as the control group. The reduced mRNA levels of adiponectin and resistin in the adipose tissue of the HFD-fed mice were significantly reversed by dietary supplementation of acetate, propionate, butyrate or their admixture to the HFD. Moreover, the expressional changes of adiponectin and resistin induced by SCFA were associated with alterations in DNA methylation at their promoters, which was mediated by reducing the expressions of enzyme-catalysed DNA methyltransferase (DNMT1, 3a, 3b) and the methyl-CpG-binding domain protein 2 (MBD2) and suppressing the binding of these enzymes to the promoters of adiponectin and resistin. Our results indicate that SCFA may correct aberrant expressions of adiponectin and resistin in obesity by epigenetic regulation.


Subject(s)
Adiponectin/metabolism , DNA Methylation , Fatty Acids, Volatile/metabolism , Resistin/metabolism , Adipokines/metabolism , Adipose Tissue , Animals , Binding Sites , Body Weight , CpG Islands , DNA (Cytosine-5-)-Methyltransferase 1/genetics , DNA (Cytosine-5-)-Methyltransferase 1/metabolism , DNA-Binding Proteins/genetics , Diet, High-Fat , Dietary Fats , Epigenesis, Genetic , Male , Mice , Mice, Inbred C57BL , Mice, Obese , Obesity/complications , Obesity/metabolism , RNA, Messenger/metabolism
8.
Br J Nutr ; 120(12): 1422-1431, 2018 12.
Article in English | MEDLINE | ID: mdl-30370882

ABSTRACT

The aim of this article was to investigate the mechanism of appetite suppression induced by high-fat diets (HFD) in blunt snout bream (Megalobrama amblycephala). Fish (average initial weight 40·0 (sem 0·35) g) were fed diets with two fat levels (6 and 11 %) with four replicates. HFD feeding for 30 d could significantly increase the weight gain rate, but feeding for 60 d cannot. Food intake of M. amblycephala began to decline significantly in fish fed the HFD for 48 d. HFD feeding for 60 d significantly reduced the expression of neuropeptide Y and elevated the expression of cocaine- and amphetamine-regulated transcript (CART), actions both in favour of suppression of appetite. The activation of fatty acid sensing was partly responsible for the weakened appetite. In addition, inflammatory factors induced by the HFD may be involved in the regulation of appetite by increasing the secretion of leptin and then activating the mammalian target of rapamycin (mTOR). Lipopolysaccharide (LPS, 2·0 mg/kg of fish weight) was administered to induce inflammation, and sampling was performed after 3, 6, 9, 12, 18, 24 and 48 h of LPS injection. Within 6-24 h of LPS injection, the food intake and appetite of M. amblycephala decreased significantly, whereas the mRNA expression of leptin and mTOR increased significantly. Our results indicate that inflammatory cytokines may be the cause of appetite suppression in M. amblycephala fed a HFD.


Subject(s)
Animal Feed , Appetite , Diet, High-Fat , Leptin/metabolism , TOR Serine-Threonine Kinases/metabolism , Animals , Cyprinidae , Eating , Fatty Acids/metabolism , Fishes , Gene Expression Regulation , Inflammation , Lipid Metabolism/genetics , Lipopolysaccharides , Liver/metabolism , Nerve Tissue Proteins/metabolism , RNA, Messenger/metabolism
9.
Br J Nutr ; 119(3): 250-258, 2018 02.
Article in English | MEDLINE | ID: mdl-29307310

ABSTRACT

This study was conducted to elucidate the effects of decaffeinated green coffee bean extract (GCE) on anthropometric indices, glycaemic control, blood pressure, lipid profile, insulin resistance and appetite in patients with the metabolic syndrome (Mets). Subjects were randomly allocated to consume 400 mg GCE or placebo capsules twice per d for 8 weeks. Both groups were advised to follow an energy balanced diet. After GCE supplementation, systolic blood pressure (SBP) significantly reduced compared with the placebo group (-13·76 (sd 8·48) v. -6·56 (sd 9·58) mmHg, P=0·01). Also, GCE treatment significantly reduced fasting blood glucose (FBS) (-5·15 (sd 60·22) v. 29·42 (sd 40·01) mg/dl (-0·28 (SD 3·34) v. 1·63 (SD 2·22) mmol/l); P=0·03) and homoeostatic model of assessment of insulin resistance in comparison to placebo (-1·41 (sd 3·33) v. 1·23 (sd 3·84), P=0·02). In addition, waist circumference (-2·40 (sd 2·54) v. -0·66 (sd 1·17) cm, P=0·009) and appetite score (-1·44 (sd 1·72) v. -0·2 (sd 1·32), P=0·01) of the individuals supplemented with GCE indicated a significant decline. Besides, weight and BMI reduction in the intervention group was almost twice as much as the placebo group; however, this discrepancy was marginally significant (weight: -2·08 (sd 2·11) v. -0·92 (sd 1·30) kg, P=0·05). No difference was observed in terms of glycated Hb (HbA1c) percentage and lipid profile parameters between the two groups. To sum up, GCE administration had an ameliorating effect on some of the Mets components such as high SBP, high FBS and Mets main aetiological factors including insulin resistance and abdominal obesity. Furthermore, GCE supplementation could reduce appetite level.


Subject(s)
Blood Glucose/analysis , Blood Pressure/drug effects , Coffea/chemistry , Insulin Resistance , Metabolic Syndrome/drug therapy , Plant Extracts/administration & dosage , Adult , Aged , Appetite/drug effects , Body Mass Index , Body Weight/drug effects , Caffeine/analysis , Dietary Supplements , Double-Blind Method , Female , Glycated Hemoglobin/analysis , Humans , Lipids/blood , Male , Metabolic Syndrome/physiopathology , Middle Aged , Placebos , Seeds/chemistry , Waist Circumference
10.
Br J Nutr ; 119(10): 1102-1110, 2018 05.
Article in English | MEDLINE | ID: mdl-29759109

ABSTRACT

Whole-grain highland hull-less barley (WHLB) contains high amounts of bioactive compounds that potentially exhibit cholesterol-lowering effects. This study investigated the hypocholesterolaemic effect of WHLB. A total of seventy-two male Sprague-Dawley rats were divided into four groups and were fed with the normal control diet, high-fat diet (HFD) and HFD containing low or high dose (10 or 48·95 %) of WHLB. High dose of WHLB significantly decreased the organ indexes of liver and abdominal fat and lipid levels of plasma and liver in HFD rats. The lipid regulation effect of WHLB, which was reconfirmed through hepatocyte morphologic observation, was accompanied by a large excretion of bile acids in the small intestinal contents and the faeces. Real-time PCR analyses, which were further reconfirmed through Western blot analyses, revealed that a high dose of WHLB significantly enhanced the hepatic expressions of AMP-activated protein kinase α, cholesterol 7α-hydroxylase, LDL receptor, liver X receptor, and PPARα and decreased the expression of 3-hydroxy-3-methylglutaryl coenzyme A reductase. It also enhanced the ileal expression of farnesoid X receptor and resulted in the decrease of expression of apical sodium-dependent bile acid transporter. WHLB exhibited hypocholesterolaemic effects mainly by inhibiting cholesterol synthesis, cholesterol accumulation in peripheral tissue, and bile acid reabsorption and by stimulating bile acid synthesis.


Subject(s)
Anticholesteremic Agents/administration & dosage , Diet, High-Fat/adverse effects , Hordeum , Whole Grains , Abdominal Fat , Animals , Bile Acids and Salts/analysis , Bile Acids and Salts/biosynthesis , Bile Acids and Salts/metabolism , Biomarkers/analysis , Cholesterol/biosynthesis , Cholesterol/genetics , Cholesterol/metabolism , Diet , Dietary Fiber/administration & dosage , Feces/chemistry , Gene Expression , Intestine, Small/chemistry , Lipid Metabolism/genetics , Lipids/analysis , Lipids/blood , Liver/chemistry , Liver/metabolism , Male , RNA, Messenger/analysis , Rats , Rats, Sprague-Dawley
11.
Nutr Res Rev ; 31(2): 239-247, 2018 12.
Article in English | MEDLINE | ID: mdl-29871706

ABSTRACT

Obesity represents one of major health problems strongly linked to other co-morbidities, such as type 2 diabetes, CVD, gastrointestinal disorders and cognitive impairment. In this context, nutritional stress, such as an excess of fat intake, promotes a systemic oxidative stress, characterised by hyperproduction of reactive oxygen species, leading to cellular alterations that include impaired energy metabolism, altered cell signalling and cell cycle control, impaired cell transport mechanisms and overall dysfunctional biological activity. Flavonoids, dietary components of plant foods, are endowed with a wide spectrum of biological activities, including antioxidant activity, and have been proposed to reduce the risk of major chronic diseases. The present review intends to highlight and critically discuss the current scientific evidence on the possible effects of flavonoids in counteracting obesity and related co-morbidities (i.e. type 2 diabetes mellitus, CVD, gastrointestinal disorders and cognitive impairment) through a decrease in oxidative stress and related inflammatory conditions.


Subject(s)
Cardiovascular Diseases/metabolism , Cognitive Dysfunction/metabolism , Diabetes Mellitus, Type 2/metabolism , Flavonoids/therapeutic use , Gastrointestinal Diseases/metabolism , Obesity/metabolism , Oxidative Stress/drug effects , Animals , Antioxidants/pharmacology , Antioxidants/therapeutic use , Cardiovascular Diseases/diet therapy , Cognitive Dysfunction/diet therapy , Comorbidity , Diabetes Mellitus, Type 2/diet therapy , Diet , Energy Metabolism/drug effects , Flavonoids/pharmacology , Gastrointestinal Diseases/diet therapy , Humans , Obesity/diet therapy , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Plants, Edible/chemistry , Polyphenols/pharmacology , Polyphenols/therapeutic use
12.
Nutr Res Rev ; 31(2): 153-163, 2018 12.
Article in English | MEDLINE | ID: mdl-29362018

ABSTRACT

It has been established that ingestion of a high-fat diet increases the blood levels of lipopolysaccharides (LPS) from Gram-negative bacteria in the gut. Obesity is characterised by low-grade systemic and adipose tissue inflammation. This is suggested to be implicated in the metabolic syndrome and obesity. In the present review, we hypothesise that LPS directly and indirectly participates in the inflammatory reaction in adipose tissue during obesity. The experimental evidence shows that LPS is involved in the transition of macrophages from the M2 to the M1 phenotype. In addition, LPS inside adipocytes may activate caspase-4/5/11. This may induce a highly inflammatory type of programmed cell death (i.e. pyroptosis), which also occurs after infection with intracellular pathogens. Lipoproteins with or without LPS are taken up by adipocytes. Large adipocytes are more metabolically active and potentially more exposed to LPS than small adipocytes are. Thus, LPS might be involved in defining the adipocyte death size and the formation of crown-like structures. The adipocyte death size is reached when the intracellular concentration of LPS initiates pyroptosis. The mechanistic details remain to be elucidated, but the observations indicate that adipocytes are stimulated to cell death by processes that involve LPS from the gut microbiota. There is a complex interplay between the composition of the diet and microbiota. This influences the amount of LPS that is translocated from the gut. In particular, the lipid content of a meal may correlate with the amount of LPS built in to chylomicrons.


Subject(s)
Adipose Tissue/cytology , Diet, High-Fat/adverse effects , Gastrointestinal Microbiome , Inflammation , Lipopolysaccharides/metabolism , Obesity , Pyroptosis , Adipocytes , Adipose Tissue/metabolism , Animals , Caspases/metabolism , Gram-Negative Bacteria/metabolism , Humans , Inflammation/etiology , Inflammation/metabolism , Inflammation/microbiology , Lipopolysaccharides/blood , Lipoproteins/metabolism , Macrophages , Obesity/complications , Obesity/metabolism , Obesity/microbiology
13.
Br J Nutr ; 117(2): 177-186, 2017 01.
Article in English | MEDLINE | ID: mdl-28132656

ABSTRACT

Hyperlipidaemia is a major cause of atherosclerosis and related CVD and can be prevented with natural substances. Previously, we reported that a novel Bacillus-fermented green tea (FGT) exerts anti-obesity and hypolipidaemic effects. This study further investigated the hypotriglyceridaemic and anti-obesogenic effects of FGT and its underlying mechanisms. FGT effectively inhibited pancreatic lipase activity in vitro (IC50, 0·48 mg/ml) and ameliorated postprandial lipaemia in rats (26 % reduction with 500 mg/kg FGT). In hypertriglyceridaemic hamsters, FGT administration significantly reduced plasma TAG levels. In mice, FGT administration (500 mg/kg) for 2 weeks augmented energy expenditure by 22 % through the induction of plasma serotonin, a neurotransmitter that modulates energy expenditure and mRNA expressions of lipid metabolism genes in peripheral tissues. Analysis of the gut microbiota showed that FGT reduced the proportion of the phylum Firmicutes in hamsters, which could further contribute to its anti-obesity effects. Collectively, these data demonstrate that FGT decreases plasma TAG levels via multiple mechanisms including inhibition of pancreatic lipase, augmentation of energy expenditure, induction of serotonin secretion and alteration of gut microbiota. These results suggest that FGT may be a useful natural agent for preventing hypertriglyceridaemia and obesity.


Subject(s)
Camellia sinensis , Energy Metabolism/drug effects , Fermentation , Hyperlipidemias/blood , Hypolipidemic Agents/pharmacology , Lipase/antagonists & inhibitors , Plant Extracts/pharmacology , Animals , Anti-Obesity Agents/pharmacology , Anti-Obesity Agents/therapeutic use , Bacillus , Firmicutes , Gastrointestinal Microbiome/drug effects , Hyperlipidemias/drug therapy , Hypertriglyceridemia/blood , Hypertriglyceridemia/drug therapy , Hypolipidemic Agents/therapeutic use , Lipid Metabolism/drug effects , Lipid Metabolism/genetics , Mesocricetus , Mice , Mice, Inbred C57BL , Pancreas/enzymology , Phytotherapy , Plant Extracts/metabolism , Plant Extracts/therapeutic use , RNA, Messenger/metabolism , Serotonin/blood , Tea , Triglycerides/blood
14.
Br J Nutr ; 117(5): 645-661, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28367764

ABSTRACT

Balance between adipocyte and osteoblast differentiation is the key link of disease progression in obesity and osteoporosis. We have previously reported that formononetin (FNT), an isoflavone extracted from Butea monosperma, stimulates osteoblast formation and protects against postmenopausal bone loss. The inverse relationship between osteoblasts and adipocytes prompted us to analyse the effect of FNT on adipogenesis and in vivo bone loss, triggered by high-fat diet (HFD)-induced obesity. The anti-obesity effect and mechanism of action of FNT was determined in 3T3-L1 cells and HFD-induced obese male mice. Our findings show that FNT suppresses the adipogenic differentiation of 3T3-L1 fibroblasts, through down-regulation of key adipogenic markers such as PPARγ, CCAAT/enhancer-binding protein alpha (C/EBPα) and sterol regulatory element-binding protein (SREBP) and inhibits intracellular TAG accumulation. Increased intracellular reactive oxygen species levels and AMP-activated protein kinase (AMPK) activation accompanied by stabilisation of ß-catenin were attributed to the anti-adipogenic action of FNT. In vivo, 12 weeks of FNT treatment inhibited the development of obesity in mice by attenuating HFD-induced body weight gain and visceral fat accumulation. The anti-obesity effect of FNT results from increased energy expenditure. FNT also protects against HFD-induced dyslipidaemia and rescues deterioration of trabecular bone volume by increasing bone formation and decreasing bone resorbtion caused by HFD. FNT's rescuing action against obesity-induced osteoporosis commenced at the level of progenitors, as bone marrow progenitor cells, obtained from the HFD mice group supplemented with FNT, showed increased osteogenic and decreased adipogenic potentials. Our findings suggest that FNT inhibits adipogenesis through AMPK/ß-catenin signal transduction pathways and protects against HFD-induced obesity and bone loss.


Subject(s)
AMP-Activated Protein Kinases/metabolism , Adipogenesis/drug effects , Isoflavones/pharmacology , Obesity/prevention & control , Osteoporosis/prevention & control , beta Catenin/metabolism , 3T3-L1 Cells , Adipocytes/drug effects , Adipocytes/metabolism , Animals , Bone Marrow Cells/cytology , Bone Marrow Cells/metabolism , Bone Resorption/drug therapy , Cell Differentiation/drug effects , Diet, High-Fat/adverse effects , Disease Models, Animal , Energy Metabolism/drug effects , Male , Mice , Mice, Inbred C57BL , Obesity/etiology , Osteoporosis/etiology , Reactive Oxygen Species/metabolism , Signal Transduction/drug effects , Uncoupling Protein 1/genetics , Up-Regulation/drug effects
15.
Br J Nutr ; 116(3): 434-42, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27221157

ABSTRACT

The human circadian system anticipates and adapts to daily environmental changes to optimise behaviour according to time of day and temporally partitions incompatible physiological processes. At the helm of this system is a master clock in the suprachiasmatic nuclei (SCN) of the anterior hypothalamus. The SCN are primarily synchronised to the 24-h day by the light/dark cycle; however, feeding/fasting cycles are the primary time cues for clocks in peripheral tissues. Aligning feeding/fasting cycles with clock-regulated metabolic changes optimises metabolism, and studies of other animals suggest that feeding at inappropriate times disrupts circadian system organisation, and thereby contributes to adverse metabolic consequences and chronic disease development. 'High-fat diets' (HFD) produce particularly deleterious effects on circadian system organisation in rodents by blunting feeding/fasting cycles. Time-of-day-restricted feeding, where food availability is restricted to a period of several hours, offsets many adverse consequences of HFD in these animals; however, further evidence is required to assess whether the same is true in humans. Several nutritional compounds have robust effects on the circadian system. Caffeine, for example, can speed synchronisation to new time zones after jetlag. An appreciation of the circadian system has many implications for nutritional science and may ultimately help reduce the burden of chronic diseases.


Subject(s)
Circadian Clocks/physiology , Circadian Rhythm/physiology , Feeding Behavior , Nutritional Physiological Phenomena , Nutritional Status/physiology , Obesity/etiology , Animals , Diet, High-Fat/adverse effects , Humans , Obesity/physiopathology
16.
Br J Nutr ; 115(7): 1155-66, 2016 Apr 14.
Article in English | MEDLINE | ID: mdl-26856891

ABSTRACT

The prevalence of the metabolic syndrome components including abdominal obesity, dyslipidaemia and insulin resistance is increasing in both developed and developing countries. It is generally accepted that the development of these features is preceded by, or accompanied with, impaired mitochondrial function. The present study was designed to analyse the effects of a mitochondrial-targeted lipophilic ubiquinone (MitoQ) on muscle lipid profile modulation and mitochondrial function in obesogenic diet-fed rats. For this purpose, twenty-four young male Sprague-Dawley rats were divided into three groups and fed one of the following diets: (1) control, (2) high fat (HF) and (3) HF+MitoQ. After 8 weeks, mitochondrial function markers and lipid metabolism/profile modifications in skeletal muscle were measured. The HF diet was effective at inducing the major features of the metabolic syndrome--namely, obesity, hepatic enlargement and glucose intolerance. MitoQ intake prevented the increase in rat body weight, attenuated the increase in adipose tissue and liver weights and partially reversed glucose intolerance. At the muscle level, the HF diet induced moderate TAG accumulation associated with important modifications in the muscle phospholipid classes and in the fatty acid composition of total muscle lipid. These lipid modifications were accompanied with decrease in mitochondrial respiration. MitoQ intake corrected the lipid alterations and restored mitochondrial respiration. These results indicate that MitoQ protected obesogenic diet-fed rats from some features of the metabolic syndrome through its effects on muscle lipid metabolism and mitochondrial activity. These findings suggest that MitoQ is a promising candidate for future human trials in the metabolic syndrome prevention.


Subject(s)
Diet, High-Fat , Adipose Tissue/pathology , Animals , Fatty Acids/analysis , Glucose Intolerance/prevention & control , Lipid Metabolism/drug effects , Lipids/analysis , Liver/pathology , Male , Metabolic Syndrome/prevention & control , Mitochondria/drug effects , Mitochondria/physiology , Muscle, Skeletal/chemistry , Muscle, Skeletal/drug effects , Muscle, Skeletal/metabolism , Obesity/etiology , Obesity/metabolism , Organ Size/drug effects , Phospholipids/analysis , Rats , Rats, Sprague-Dawley , Triglycerides/metabolism , Ubiquinone/analogs & derivatives , Ubiquinone/pharmacology , Weight Gain/drug effects
17.
Br J Nutr ; 116(8): 1346-1355, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27680963

ABSTRACT

Epidemiological data show that osteoarthritis (OA) is significantly associated with lower birth weight, and that OA may be a type of fetal-originated adult disease. The present study aimed to investigate the prenatal food-restriction (PFR) effect on the quality of articular cartilage in female offspring to explore the underlying mechanisms of fetal-originated OA. Maternal rats were fed a restricted diet from gestational day (GD) 11 to 20 to induce intra-uterine growth retardation. Female fetuses and female adult offspring fed a post-weaning high-fat diet were killed at GD20 and postnatal week 24, respectively. Serum and knee cartilage samples from fetuses and adult female offspring were collected and examined for cholesterol metabolism and histology. Fetal serum corticosterone and insulin-like growth factor-1 (IGF-1) in the PFR group were lower than those of the control, but the serum cholesterol level was not changed. The lower expression of IGF-1 in the PFR group lasted into adulthood. The expression of extracellular matrix (ECM) genes, including type II collagen, aggrecan and cholesterol efflux genes including liver X receptor, were significantly induced, but the ATP-binding-cassette transporter A1 was unchanged. PFR could induce a reduction in ECM synthesis and impaired cholesterol efflux in female offspring, and eventually led to poor quality of articular cartilage and OA.


Subject(s)
Cartilage Diseases/etiology , Cartilage, Articular/pathology , Disease Models, Animal , Extracellular Matrix Proteins/metabolism , Fetal Development , Fetal Growth Retardation/physiopathology , Osteoarthritis, Knee/etiology , Animals , Caloric Restriction/adverse effects , Cartilage Diseases/embryology , Cartilage Diseases/metabolism , Cartilage Diseases/pathology , Cartilage, Articular/embryology , Cartilage, Articular/metabolism , Cholesterol/blood , Cholesterol/metabolism , Diet, High-Fat/adverse effects , Dyslipidemias/etiology , Dyslipidemias/physiopathology , Extracellular Matrix Proteins/genetics , Female , Fetal Growth Retardation/etiology , Gene Expression Profiling , Gene Expression Regulation, Developmental , Insulin-Like Growth Factor I/analysis , Maternal Nutritional Physiological Phenomena , Osteoarthritis, Knee/embryology , Osteoarthritis, Knee/metabolism , Osteoarthritis, Knee/pathology , Pregnancy , Random Allocation , Rats, Wistar , Specific Pathogen-Free Organisms , Weaning
18.
Br J Nutr ; 115(1): 6-13, 2016 Jan 14.
Article in English | MEDLINE | ID: mdl-26507559

ABSTRACT

Type 2 diabetes (T2D) is a major risk factor of CVD. The effects of purified sardine proteins (SP) were examined on glycaemia, insulin sensitivity and reverse cholesterol transport in T2D rats. Rats fed a high-fat diet (HFD) for 5 weeks, and injected with a low dose of streptozotocin, were used. The diabetic rats were divided into four groups, and they were fed casein (CAS) or SP combined with 30 or 5% lipids, for 4 weeks. HFD-induced hyperglycaemia, insulin resistance and hyperlipidaemia in rats fed HFD, regardless of the consumed protein. In contrast, these parameters lowered in rats fed SP combined with 5 or 30% lipids, and serum insulin values reduced in SP v. CAS. HFD significantly increased total cholesterol and TAG concentrations in the liver and serum, whereas these parameters decreased with SP, regardless of lipid intake. Faecal cholesterol excretion was higher with SP v. CAS, combined with 30 or 5% lipids. Lecithin:cholesterol acyltransferase (LCAT) activity and HDL3-phospholipids (PL) were higher in CAS-HF than in CAS, whereas HDL2-cholesteryl esters (CE) were lower. Otherwise, LCAT activity and HDL2-CE were higher in the SP group than in the CAS group, whereas HDL3-PL and HDL3-unesterified cholesterol were lower. Moreover, LCAT activity lowered in the SP-HF group than in the CAS-HF group, when HDL2-CE was higher. In conclusion, these results indicate the potential effects of SP to improve glycaemia, insulin sensitivity and reverse cholesterol transport, in T2D rats.


Subject(s)
Cholesterol/blood , Diabetes Mellitus, Type 2/diet therapy , Fish Proteins/therapeutic use , Fishes , Hyperglycemia/drug therapy , Hyperlipidemias/drug therapy , Sterol O-Acyltransferase/metabolism , Animals , Blood Glucose/metabolism , Cholesterol Esters/blood , Diabetes Mellitus, Experimental/diet therapy , Diabetes Mellitus, Experimental/etiology , Diabetes Mellitus, Type 2/etiology , Diet, High-Fat , Fish Proteins/pharmacology , Hyperlipidemias/blood , Insulin Resistance , Lecithins/metabolism , Lipids/blood , Male , Phospholipids/metabolism , Rats, Wistar
19.
Br J Nutr ; 114(8): 1180-7, 2015 Oct 28.
Article in English | MEDLINE | ID: mdl-26299683

ABSTRACT

Administration of Lactobacillus gasseri SBT2055 (LG2055) has been shown to prevent body weight gain and it also down-regulates the expression of the Ccl2 gene in adipose tissue in diet-induced obese mice. The CC chemokine ligand 2 has a crucial role in macrophage infiltration into adipose tissue, which is known to exacerbate inflammation. However, it is not yet known how LG2055 affects the invasion of macrophages into adipose tissue. C57BL/6J male mice were fed a normal-fat diet (10 % energy fat), high-fat diet (HFD; 45 % energy fat), or HFD containing LG2055 for 12 weeks. After the feeding period, gene expression and macrophage population in adipose tissue were analysed by real-time PCR and flow cytometry, respectively. Body weight and abdominal fat weight were not altered by feeding LG2055. Flow cytometry analysis revealed that the population of macrophages in adipose tissue was significantly reduced by feeding LG2055 compared with HFD only. Furthermore, the ratio of classically activated inflammatory macrophages (M1 macrophages) to total macrophages was significantly decreased in the LG2055-fed group. The expressions of Ccl2, Ccr2 and Lep were down-regulated and that of Il6, Tnf and Nos2 tended to be down-regulated in adipose tissue by feeding LG2055. In addition, fasting glucose levels were significantly decreased in the LG2055-fed group. These data suggest that administration of LG2055 might attenuate inflammation, which is caused by the intake of an HFD, through the inhibition of macrophage invasion into adipose tissue.


Subject(s)
Adipose Tissue/metabolism , Diet, High-Fat/adverse effects , Lactobacillus , Macrophages/metabolism , Abdominal Fat/metabolism , Animals , Blood Glucose/metabolism , Body Weight , Chemokine CCL2/genetics , Chemokine CCL2/metabolism , Down-Regulation , Energy Intake , Inflammation/therapy , Insulin/blood , Interleukin-6/metabolism , Male , Mice , Mice, Inbred C57BL , Mice, Obese , Nitric Oxide Synthase Type II/genetics , Nitric Oxide Synthase Type II/metabolism , Obesity/therapy , Receptors, CCR2/genetics , Receptors, CCR2/metabolism , Weight Gain
20.
Br J Nutr ; 114(8): 1123-31, 2015 Oct 28.
Article in English | MEDLINE | ID: mdl-26314315

ABSTRACT

Dietary anthocyanins have been shown to reduce inflammation in animal models and may ameliorate obesity-related complications. Black elderberry is one of the richest sources of anthocyanins. We investigated the metabolic effects of anthocyanin-rich black elderberry extract (BEE) in a diet-induced obese C57BL/6J mouse model. Mice were fed either a low-fat diet (n 8), high-fat lard-based diet (HFD; n 16), HFD+0·25 % (w/w) BEE (0·25 %-BEE; n 16) or HFD+1·25 % BEE (1·25 %-BEE; n 16) for 16 weeks. The 0·25 % BEE (0·034 % anthocyanin, w/w) and 1·25 % BEE (0·17 % anthocyanin, w/w) diets corresponded to estimated anthocyanin doses of 20-40 mg and 100-200 mg per kg of body weight, respectively. After 16 weeks, both BEE groups had significantly lower liver weights, serum TAG, homoeostasis model assessment and serum monocyte chemoattractant protein-1 compared with HFD. The 0·25 %-BEE also had lower serum insulin and TNFα compared with HFD. Hepatic fatty acid synthase mRNA was lower in both BEE groups, whereas PPARγ2 mRNA and liver cholesterol were lower in 1·25 %-BEE, suggesting decreased hepatic lipid synthesis. Higher adipose PPARγ mRNA, transforming growth factor ß mRNA and adipose tissue histology suggested a pro-fibrogenic phenotype that was less inflammatory in 1·25 %-BEE. Skeletal muscle mRNA expression of the myokine IL-6 was higher in 0·25 %-BEE relative to HFD. These results suggest that BEE may have improved some metabolic disturbances present in this mouse model of obesity by lowering serum TAG, inflammatory markers and insulin resistance.


Subject(s)
Diet, High-Fat/adverse effects , Inflammation/drug therapy , Obesity/drug therapy , Plant Extracts/pharmacology , Sambucus nigra/chemistry , Adipose Tissue/drug effects , Adipose Tissue/metabolism , Animals , Body Weight , Chemokine CCL2/blood , Diet, Fat-Restricted , Dietary Fats/administration & dosage , Dietary Fats/adverse effects , Disease Models, Animal , Dose-Response Relationship, Drug , Insulin/blood , Insulin Resistance , Interleukin-6/metabolism , Liver/drug effects , Liver/metabolism , Male , Mice , Mice, Inbred C57BL , Mice, Obese , Muscle, Skeletal/drug effects , Muscle, Skeletal/metabolism , PPAR gamma/genetics , PPAR gamma/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Tumor Necrosis Factor-alpha/blood
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