Quercetin induces hepatic lipid omega-oxidation and lowers serum lipid levels in mice

Quercetin ameliorates lipid deposition in primary hepatocytes of the chicken embryo

1. The accumulation of excessive fat plays a role in the development of non-alcoholic fatty liver disease (NAFLD) and phytogenic feed additives have the potential to ameliorate this. This study involved the isolation and culture of primary hepatocytes from chicken embryos to establish a model of hepatic steatosis induced by oleic acid/dexamethasone (OA/DEX). Lipid accumulation and cell viability were assessed using Nile Red staining, Oil Red O staining and cell count Kit -8 (CCK8) following treatment with varying concentrations of quercetin (Que). The potential mechanism by which Que exerts its effects was preliminarily investigated.2. The results indicated that OA effectively treated lipid accumulation in hepatocytes. There was no notable variance in cell proliferation between the normal and OA/DEX groups when subjected to Que treatment at concentrations of 1000 ng/ml and 10 000 ng/ml. Triglycerides and cholesterol (low and high density) decreased with Que treatment, with the most substantial reduction observed at 10 000 ng/ml.3. Gene expression levels decreased to levels similar to those in the control groups. Western blot data demonstrated that sterol regulatory element-binding protein 1 (SREBP-1) protein expression correlated with its mRNA expression level. Que mitigated lipid accumulation through the alpha serine/threonine protein kinase (AKT) and extracellular signal-regulated kinase (ERK) pathways. Expression levels of lipid-related genes (APOB, PPARα, CYP3A5 and SREBP-1) decreased to levels similar to the control groups. Western blot data demonstrated that the SREBP-1 protein expression correlated with its mRNA expression level.4. Supplementation with Que ameliorated lipid accumulation through AKT and ERK signalling pathway in OA/DEX-induced high-fat hepatocytes.

Dietary Flavonoids Consumption and Health: An Umbrella Review

SCOPE

The current evidence between dietary flavonoids consumption and multiple health outcomes is inadequate and inconclusive. To summarize and evaluate the evidence for dietary flavonoids consumption and multiple health outcomes, an umbrella review of meta-analyses and systematic reviews is conducted.

METHODS AND RESULTS

PubMed, Ovid-EMBASE, and the Cochrane Database of Systematic Reviews are searched up to January 2024. The study includes a total of 32 articles containing 24 unique health outcomes in this umbrella review. Meta-analyses are recalculated by using a random effects model. Separate analyses are performed based on the kind of different flavonoid subclasses. The study finds some unique associations such as flavonol and gastric cancer, isoflavone and uterine fibroids and endometrial cancer, total flavonoids consumption and lung cancer, ovarian cancer, and prostate cancer. Overall, the study confirms the negative associations between dietary flavonoids consumption and type 2 diabetes mellitus, cardiovascular diseases, breast cancer, colorectal cancer, lung cancer, and mortality, while positive associations are observed for prostate cancer and uterine fibroids.

CONCLUSION

Although dietary flavonoids are significantly associated with many outcomes, firm generalizable conclusions about their beneficial or harmful effects cannot be drawn because of the low certainty of evidence for most of outcomes. More well-designed primary studies are needed.

Exploration of the mechanism of Qi-Xian decoction in asthmatic mice using metabolomics combined with network pharmacology

Introduction: Qi-Xian Decoction (QXD), a traditional Chinese medicine (TCM) formula consisting of eight herbs, has been clinically used to treat asthma. However, the underlying mechanisms have not been completely elucidated. This study aimed to combine metabolomics and network pharmacology to reveal the mechanism of action of QXD in asthma treatment. Methods: An ovalbumin (OVA)-induced asthma mouse model was constructed to evaluate the therapeutic effects of QXD. Serum metabolomics and network pharmacology were combined to study the mechanism of anti-asthma action as well as the potential target, and related biological functions were validated. Results: The QXD treatment has demonstrated significant protective effects in OVA-induced asthmatic mice, as evidenced by its ability to inhibit inflammation, IgE, mucus overproduction, and airway hyperreactivity (AHR). Metabolomic analysis has revealed a total of 140 differential metabolites associated with QXD treatment. In addition, network pharmacology has identified 126 genes that are linked to the effects of QXD, including TNF, IL-6, IL1β, STAT3, MMP9, EGFR, JUN, CCL2, TLR4, MAPK3 and MAPK8. Through comprehensive gene-metabolite interaction network analysis, seven key metabolites have been identified and associated with the potential anti-asthmatic effect of QXD, with palmitic acid (PA) being the most notable among them. In vitro validation studies have confirmed the gene-metabolite interaction involving PA, IL-6, and MAPK8. Furthermore, our research has demonstrated that QXD treatment can effectively inhibit PA-promoted IL-6 expression in MH-S cells and reduce PA concentration in OVA-induced asthmatic mice. Conclusion: The regulation of metabolic pathways by QXD was found to be associated with its anti-asthmatic action, which provides insight into the mechanism of QXD in treating asthma.

Coptidis rhizoma and evodiae fructus against lipid droplet deposition in nonalcoholic fatty liver disease-related liver cancer by AKT

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease in the world. NAFLD has become one of the major factors contributing to hepatocellular carcinoma (HCC) development. However, there are no clear targets and therapeutic drugs for NAFLD-related liver cancer. This study explored the active compounds, target and mechanism of coptidis rhizoma and evodiae fructus in the treatment of NAFLD-related liver cancer based on the network pharmacology and experimental verification. There were 455 intersection targets of NAFLD-related liver cancer, and 65 drug-disease common targets. AKT1 has the highest degree, indicating that it may be a key target of coptidis rhizoma and evodiae fructus in the treatment of NAFLD-related liver cancer. The expression level of AKT1 was high in high-risk group, and the overall survival rate was lower than that in low-risk group. After oleic acid induction, p-AKT expression and lipid droplet deposition were promoted in HepG2 cells. Quercetin and resveratrol reduced lipid droplet deposition in vivo. Moreover, quercetin inhibited p-AKT expression, resveratrol both reduced the expression of p-AKT and AKT. The overall findings suggested that quercetin inhibited AKT in the treatment of NAFLD-related liver cancer.

Cardioprotective effect of the quercetin on cardiovascular remodeling and atherosclerosis in rodents fed a high-fat diet: A systematic review

Cardiovascular diseases (CVD) are the leading cause of death globally, estimated at 17.9 million premature deaths. Several risk factors contribute to the development of CVD, including unhealthy diet rich in saturated fat. Quercetin (Q) is a important natural flavonoid with cardioprotective effect. However, it is crucial to understand and clarify which dosages and intervention times quercetin promotes better cardioprotective effects when exposed to a High-Fat Diet (HFD). We aim was to carry out a review to identify and compare experimental studies that investigated the quercetin effect on cardiac parameters in rodents fed a HFD. This literature search was performed through the specialized databases PubMed, Embase, Web of Science and Lilacs in May 2022. The following information was collected and assessed: Species of animals, dietary fat content, intervention protocol (quercetin), and main results of alterations associated with cardiac change. A total of 116 articles were selected from the database and 30 articles were included in this study. The administration form of quercetin was used in the diet supplemented in 73.4% (n = 22) of the studies. The dosage ranged between 10 and 100 mg/kg, 0.01%-0.36%, and 4-8 g/kg diet. The treatment time ranged between 14 and 63 days in 48.4% studies and most of the selected studies observed changes in the: Serum concentrations of lipids (60%, n = 18) mainly decrease in TC and TG, left ventricle (LV) (16.13%, n = 5) includes attenuation of the cardiac hypertrophy; inhibition of atherosclerotic progression (32%, n = 10) with decrease in lesions and plaque formation; improvement in the expression of gene and protein associated with cardiac functionality and oxidative stress (51.6%; n = 16). Quercetin supplementation at different concentrations/doses promotes important cardioprotective effects in experimental models exposed to a HFD. The supplemented diet was shown to be the better administration option. The methodological variation presented in the articles selected in this review proves that the most appropriate intervention protocol, as well as the most effective route of administration, promotes these effects.

Managing ferroptosis-related diseases with indirect dietary modulators of ferroptosis

Ferroptosis is an iron-dependent form of programmed cell death driven by excessive oxidation of polyunsaturated phospholipids on cellular membranes. Accumulating evidence suggests that ferroptosis has been implicated in the pathological process of various diseases, such as cardiovascular diseases, neurological diseases, liver diseases, kidney injury, lung injury, diabetes, and cancer. Targeting ferroptosis is therefore considered to be a reasonable strategy to fight against ferroptosis-associated diseases. Many dietary bioactive agents have been identified to be able to either suppress or promote ferroptosis, indicating that ferroptosis-based intervention by dietary approach may be an effective strategy for preventing and treating diseases associated with ferroptosis dysregulation. In this review, we summarize the present understanding of the functional role of ferroptosis in the pathogenesis of aforementioned diseases with an emphasis on the evidence of managing ferroptosis-related diseases with indirect dietary modulators of ferroptosis and propose issues that need to be addressed to promote practical application of dietary approach targeting ferroptosis.

Multi-omics reveals hypertrophy of adipose tissue and lipid metabolism disorder via mitochondria in young mice under real-ambient exposure to air pollution

Air pollution has become one of the most serious health risks as a result of industrialization, especially in developing countries. More attention has been drawn to the relationship between obesity/overweight and fine particulate matter (PM2.5). Especially for susceptible populations, the impact of air pollution on children and adolescents has attracted more public attentions. However, the detailed underlying mechanism influencing obesity or overweight under PM2.5 exposure is still unknown. Therefore, young mice were exposed to PM2.5 using the real-ambient exposure system that we previously established in Shijiazhuang city. Compared with the traditionally concentrated air particle (CAP) system, our real-ambient exposure system provides similar PM2.5 concentrations and characteristics as outdoor ambient air and minimizes the influence of external interfering factors. After 8 weeks of exposure to PM2.5, the weight of gonadal white adipose tissue (gWAT) and subcutaneous white adipose tissue (sWAT) was considerably increased, accompanied by a significantly enlarged size of adipocytes in sWAT. Importantly, multiomics analysis indicated altered metabolites involved in the lipid metabolism pathway, and transcriptomic analysis revealed notably changed signaling pathways related to fatty acid metabolism. Moreover, the mtDNA copy number, mitochondrial activity and fatty acid oxidation (FAO) were increased in the liver under PM2.5 exposure. Taken together, our research investigated the hypotrophy of adipose tissue in young mice, supported an imbalance in lipid metabolism based on multiomics analysis, and revealed disordered mitochondrial function under PM2.5 exposure. Our study provided new insight into the hazardous effects of air pollution, and extended our understanding on the underlying mechanism.

Effects of Nelumbo nucifera Leaf Extract on Obesity

The two main components from a Nelumbo nucifera leaf extract (NnEx) were investigated for their ability to prevent triglyceride accumulation and promoting lipolysis. Sun-dried Nelumbo nucifera leaves were immersed in hot water to extract the soluble components, and the resulting solution was analyzed by LC-MS and nuclear magnetic resonance. The results showed that quercetin-3-O-ß-glucuronide (Q3GA) and quercetin were the key components of the NnEx. In vitro experiments confirmed that quercetin and Q3GA functioned in lipid metabolism by promoting triglyceride degradation through inhibition of the cAMP pathway. In vivo experiments showed that NnEx ingestion inhibited the accumulation of neutral fats in ICR mice and transitioned the hepatocytes of type II diabetic KK-Ay mice out of glycogenosis. These results highlight the ability of NnEx to control metabolism by modulating fat and sugar absorption and may provide an interesting novel treatment for obesity and related lifestyle diseases such as type II diabetes.

Protocatechuic acid and quercetin glucosides in onions attenuate changes induced by high fat diet in rats

Yellow onion waste from industrial peeling was used to obtain three pure preparations: protocatechuic acid (PA), quercetin diglycosides (QD) and quercetin monoglycosides (QM). PA contained 61% protocatechuic acid, QD contained 35% quercetin diglucosides, mainly quercetin-3,4'-diglucoside, and QM contained 41% monoglucosides, mainly quercetin-4'-glucoside. The highest antioxidant activity was shown by PA. The effects of preparations on the digestive functions of the gastrointestinal tract of rats as well as the biochemical parameters and antioxidant capacity of the blood in model research on Wistar rats sustained by a high-fat diet were assessed (5 groups per 8 animals). The results of the present experiment showed that different onion phenolic preparations differently modulated the enzymatic activity of faecal (P < 0.001) and caecal (P < 0.001) microbiota. For instance, the QD preparation but not QM efficiently reduced the faecal and caecal bacterial β-glucuronidase activity. Both protocatechuic acid and quercetin monoglycosides showed a beneficial effect by regulating blood lipids (reduction of TC (P < 0.001) and TG (P < 0.001), non-HDL increase in HDL (P < 0.001)), thereby lowering the risk factors for atherosclerotic lesions AI (P = 0.038) and AII (P = 0.013). In addition, onion phenols showed a strong antioxidant effect, however, with a different mechanism: protocatechuic acid via serum ACL (P = 0.033) increase and hepatic GSSG (P = 0.070) decrease, QM via ACW (P < 0.001) increase and hepatic TBARS (P = 0.002) decrease, and QD via serum ACW increase and hepatic GSSG decrease. It can be concluded that onion polyphenols with a lower molar weight, i.e. QM more preferably affect the blood lipid profile than QD. However QD more efficiently reduced the faecal and caecal bacterial β-glucuronidase activity.

Malus hupehensis leaves extract attenuates obesity, inflammation, and dyslipidemia by modulating lipid metabolism and oxidative stress in high-fat diet-induced obese mice

Malus hupehensis leaves (MHL) are used to make traditional Chinese tea. In this study, MHL extract was shown to improve metabolic disorders and inflammatory response in high-fat diet-induced obese mice. MHL extract could reduce body weight, and significantly alleviate liver damage and fat accumulation. MHL extract caused a decrease in the levels of ALT, AST, AKP, TC, TG, LDL-C, and an increase in the level of HDL-C. It also caused a decrease in inflammatory cytokines, including TNF-α, IFN-γ, IL-1β, IL-6, and an increase in the anti-inflammatory cytokine IL-10 and IL-4. MHL extract could upregulate mRNA expression of PPAR-α, LPL, CPT1, CYP7A1, SOD1, SOD2, CAT, GSH1, and GSH-Px and downregulate that of PPAR-γ and C/EBP-α in the liver of obese mice. In conclusion, our work represents the first study demonstrating that MHL extract possesses an anti-obesity effect and alleviates obesity-related symptoms, including dyslipidemia, chronic low-grade inflammatory, and liver damage. PRACTICAL APPLICATIONS: The research may contribute to the development and application of MHL as functional foods or dietary supplement to fight against obesity.

Propagule Powder of Japanese Yam (Dioscorea Japonica) Reduces High-Fat Diet-Induced Metabolic Stress in Mice through the Regulation of Hepatic Gene Expression

SCOPE

Japanese yam propagules are supposed to have high potential as a functional food. However, there are almost no studies examining their physiological function. This study aims to elucidate the physiological function of Japanese yam propagules that are heated, freeze-dried, and powdered.

METHODS AND RESULTS

A high-fat diet with Japanese yam propagules is administered to mice for 4 weeks. High-fat loading induces a decline in respiratory quotient, and a high-fat diet with propagules reduces it more. This result suggests that propagules increase fat oxidation, indicating fat utilization. The hepatic transcriptome is analyzed using a DNA microarray. Some of the genes affected by high-fat loading are reversed by simultaneous ingestion of propagules. Such genes are mainly involved in the immune system and fat metabolism. High-fat loading induces hepatic inflammation, which is repressed by simultaneous ingestion of propagules. For lipid metabolism, propagules repress an increase in cholesterol biosynthesis and catabolism by high-fat loading. Regarding carbohydrate metabolism, propagules decrease glycolysis and glycogen synthesis and increase gluconeogenesis. Moreover, amino acids are converted into pyruvate and then used for gluconeogenesis.

CONCLUSION

Propagules act to delay the occurrence of hepatic disease by suppressing carbohydrate and fat metabolism disorders in high-fat loaded mice.

Omega-3 Phospholipids from Krill Oil Enhance Intestinal Fatty Acid Oxidation More Effectively than Omega-3 Triacylglycerols in High-Fat Diet-Fed Obese Mice

Antisteatotic effects of omega-3 fatty acids (Omega-3) in obese rodents seem to vary depending on the lipid form of their administration. Whether these effects could reflect changes in intestinal metabolism is unknown. Here, we compare Omega-3-containing phospholipids (krill oil; ω3PL-H) and triacylglycerols (ω3TG) in terms of their effects on morphology, gene expression and fatty acid (FA) oxidation in the small intestine. Male C57BL/6N mice were fed for 8 weeks with a high-fat diet (HFD) alone or supplemented with 30 mg/g diet of ω3TG or ω3PL-H. Omega-3 index, reflecting the bioavailability of Omega-3, reached 12.5% and 7.5% in the ω3PL-H and ω3TG groups, respectively. Compared to HFD mice, ω3PL-H but not ω3TG animals had lower body weight gain (−40%), mesenteric adipose tissue (−43%), and hepatic lipid content (−64%). The highest number and expression level of regulated intestinal genes was observed in ω3PL-H mice. The expression of FA ω-oxidation genes was enhanced in both Omega-3-supplemented groups, but gene expression within the FA β-oxidation pathway and functional palmitate oxidation in the proximal ileum was significantly increased only in ω3PL-H mice. In conclusion, enhanced intestinal FA oxidation could contribute to the strong antisteatotic effects of Omega-3 when administered as phospholipids to dietary obese mice.

Protective effects of quercetin against oxidative stress induced by bisphenol-A in rat cardiac mitochondria

Research has shown a relationship between the exposures to a chemical agent called bisphenol-A (BPA), which is extensively used in the production of polycarbonate plastics and the incidence of cardiovascular diseases. This association is most likely caused by the BPA's ability to disrupt multiple cardiac mechanisms, including mitochondrial functions. Therefore, this study aimed to explore the ability of quercetin (QUER) to limit the cardiotoxic effect of BPA in the rat's cardiac mitochondria. The experiment was carried out on 32 male Wistar rats, which were randomly assigned to four groups. The negative control group received olive oil; the positive control group received olive oil plus BPA (250 mg/kg); the third group received olive oil, BPA, and QUER (75 mg/kg); and the fourth group received olive oil and QUER, all orally for 14 days. The rats were slaughtered 24 h after the last treatment. The measured parameters included creatine kinase-MB (CK-MB) and lactate dehydrogenase (LDH) as the biomarkers of cardiotoxicity, triglyceride (TG), total cholesterol (TC), and low-density and high-density lipoprotein cholesterol (LDL-C and HDL-C) as the measures of dyslipidemia, glutathione (GSH) content, catalase activity (CAT), reactive oxygen species (ROS), lipid peroxidation (LPO), and the level of damage to the mitochondrial membranes as the indicators of the impact of QUER on the BPA cardiotoxic effect. Finally, the rats treated with QUER showed better results in terms of serum CK-MB, serum LDH, serum lipid profile, GSH level, CAT activity, mitochondrial membrane potential (ΔΨm), LPO, and ROS. According to the results, QUER could be used as a protective agent against BPA-induced mitochondrial toxicity.

In ovaries with high or low variation in follicle size, granulosa cells of antral follicles exhibit distinct size-related processes

Antral follicle size might be a valuable additive predictive marker for IVF outcome. To better understand consequences of antral follicle size as a marker for reproductive outcome, we aimed to obtain insight in follicle size-related granulosa cell processes, as granulosa cells play an essential role in follicular development via the production of growth factors, steroids and metabolic intermediates. Using the pig as a model, we compared gene expression in granulosa cells of smaller and larger follicles in the healthy antral follicle pool of sows, which had a high variation versus low variation in follicle size. Selected gene expression was confirmed at the protein level. Granulosa cells of smaller antral follicles showed increased cell proliferation, which was accompanied by a metabolic shift towards aerobic glycolysis (i.e. the Warburg effect), similar to other highly proliferating cells. High granulosa cell proliferation rates in smaller follicles might be regulated via increased granulosa cell expression of the androgen receptor and the epidermal growth factor receptor, which are activated in response to locally produced mitogens. While granulosa cells of smaller follicles in the pool are more proliferative, granulosa cells of larger follicles express more maturation markers such as insulin-like growth factor-1 (IGF1) and angiopoietin 1 (ANGPT1) and are therefore more differentiated. As both higher IGF1 and ANGPT1 have been associated with better IVF outcomes, the results of our study imply that including smaller follicles for oocyte aspiration might have negative consequences for IVF outcome.

White Adipose Tissue Response of Obese Mice to Ambient Oxygen Restriction at Thermoneutrality: Response Markers Identified, but no WAT Inflammation

Obesity is associated with white adipose tissue (WAT) hypoxia and inflammation. We aimed to test whether mild environmental oxygen restriction (OxR, 13% O₂), imposing tissue hypoxia, triggers WAT inflammation in obese mice. Thirteen weeks diet-induced obese male adult C57BL/6JOlaHsd mice housed at thermoneutrality were exposed for five days to OxR versus normoxia. WAT and blood were isolated and used for analysis of metabolites and adipokines, WAT histology and macrophage staining, and WAT transcriptomics. OxR increased circulating levels of haemoglobin and haematocrit as well as hypoxia responsive transcripts in WAT and decreased blood glucose, indicating systemic and tissue hypoxia. WAT aconitase activity was inhibited. Macrophage infiltration as marker for WAT inflammation tended to be decreased, which was supported by down regulation of inflammatory genes S100a8, Ccl8, Clec9a, Saa3, Mgst2, and Saa1. Other down regulated processes include cytoskeleton remodelling and metabolism, while response to hypoxia appeared most prominently up regulated. The adipokines coiled-coil domain containing 3 (CCDC3) and adiponectin, as well as the putative WAT hormone cholecystokinin (CCK), were reduced by OxR on transcript (Cck, Ccdc3) and/or serum protein level (adiponectin, CCDC3). Conclusively, our data demonstrate that also in obese mice OxR does not trigger WAT inflammation. However, OxR does evoke a metabolic response in WAT, with CCDC3 and adiponectin as potential markers for systemic or WAT hypoxia.

Flavonoids Fraction of Mespilus Germanica Alleviates Insulin Resistance in Metabolic Syndrome Model of Ovariectomized Rats via Reduction in Tumor Necrosis Factor-α

Objectives

The rate of metabolic syndrome (MetS) in women diagnosed as they age is one of the main concerns of health cares. Recently new strategies used to prevent progressions of MetS toward the diagnosis of diabetes have focused on plant flavonoids. This study was aimed to investigate the beneficial effects of flavonoids fraction of Mespilus germanica leaves (MGL) on MetS in ovariectomized (OVX) rats.

Methods

Twenty-four adult female Wistar rats, weighing 200 to 250 g, were divided into 3 groups: Sham surgery, OVX + Salin, or OVX + Flavonoid. Three weeks after ovariectomy, animals displayed MetS criteria received flavonoid injection (10 mg/kg, intraperitoneally) for 21 days. Then the body weight, body mass index, waist circumference, visceral fat, fasting blood glucose, serum insulin, lipid profiles and tumor necrosis factor-α (TNF-α) were measured.

Results

Treatment with flavonoids fraction of MGL significantly decreased serum level of insulin (P = 0.011), glucose (P = 0.024), TNF-α (P = 0.010), also MetS Z score (P = 0.020) and homeostasis model assessment of insulin resistance (P = 0.007). Lipid profiles and visceral fat showed insignificant reduction.

Conclusions

Flavonoids of MGL attenuates some of the MetS components possibly via reduction in TNF-α inflammatory cytokine.

Isoquercetin Improves Hepatic Lipid Accumulation by Activating AMPK Pathway and Suppressing TGF-β Signaling on an HFD-Induced Nonalcoholic Fatty Liver Disease Rat Model

Isoquercetin (IQ), a glucoside derivative of quercetin, has been reported to have beneficial effects in nonalcoholic fatty liver disease (NAFLD). In this study, we investigated the potential improvement of IQ in liver lipid accumulation, inflammation, oxidative condition, and activation in Kupffer cells (KCs) on a high-fat diet (HFD) induced NAFLD models. Male Sprague-Dawley (SD) rats were induced by HFD, lipopolysaccharides/free fatty acids (LPS/FFA) induced co-culture cells model between primary hepatocytes and Kupffer cells was used to test the effects and the underlying mechanism of IQ. Molecular docking was performed to predict the potential target of IQ. Significant effects of IQ were found on reduced lipid accumulation, inflammation, and oxidative stress. In addition, AMP-activated protein kinase (AMPK) pathway was activated by IQ, and is plays an important role in lipid regulation. Meanwhile, IQ reversed the increase of activated KCs which caused by lipid overload, and also suppression of Transforming growth factor beta (TGF-β) signaling by TGF-β Recptor-1 and SMAD2/3 signaling. Finally, TGF-βR1 and TGF-βR2 were both found may involve in the mechanism of IQ. IQ can improve hepatic lipid accumulation and decrease inflammation and oxidative stress by its activating AMPK pathway and suppressing TGF-β signaling to alleviate NAFLD.

Rutin and Its Combination With Inulin Attenuate Gut Dysbiosis, the Inflammatory Status and Endoplasmic Reticulum Stress in Paneth Cells of Obese Mice Induced by High-Fat Diet

Gut dysbiosis induced by high fat diet (HF) or obesity is a predisposing factor to develop diverse inflammatory diseases. Polyphenols and fibers, often eaten together, have been reported to have prebiotic actions, but their health promoting benefits still need to be further characterized and defined. This study attempted to understand how polyphenol rutin and polysaccharide inulin influence intestinal health in mouse model fed a HF (60 kcal%) diet. A total of 48 C57BL/6J mice were divided into four groups fed with a low fat (10% kcal%) control diet (LC), a high fat control diet (HC), a high-fat diet supplemented with rutin (HR), or a high-fat diet supplemented rutin and inulin (HRI) for 20 weeks. Rutin supplementation reduced the HF diet-induced increase of Firmicutes/Bacteroidetes (F/B) ratio, Deferribacteraceae population and plasma lipopolysaccharide (LPS) (p < 0.05); ameliorated inflammation as indicated by the decreased circulating inflammatory cytokines (p < 0.05) and the reduced expressions of intestinal inflammatory mediators (p < 0.05); and attenuated the endoplasmic reticulum (ER) stress in Paneth cells as indicated by the decreased expressions of the ER markers (p < 0.05). Compared to the rutin supplementation alone, the co-administration of rutin with inulin improved the utilization of rutin as indicated by its decreased excretion, suppressed a number of harmful bacteria including Deferribacteraceae and Desulfovibrionaceae (p < 0.05), and further reduced the expression of the key inflammatory cytokine TNF-α and increased the production of butyrate, despite the supplementation of inulin reversed the decrease of body weight induced by rutin supplementation due to an increased food intake. Taken together, our data demonstrated that rutin supplementation ameliorated the inflammatory status and ER stress in Paneth cells under a HF-induced obese state, and its co-administration with inulin further mitigated the inflammatory status, indicating the potential to combine polyphenol rutin and the polysaccharide inulin as a dietary strategy to ameliorate gut dysbiosis, to improve inflammatory status and thereby to reduce medical disorders associated with HF-induced obesity.

Flavonoids as putative modulators of Δ4-, Δ5-, and Δ6-desaturases: Studies in cultured hepatocytes, myocytes, and adipocytes

This study was conducted to screen flavonoids for affecting expression of desaturases involved in omega-3 fatty acid synthesis and ceramide (CER) metabolism. To this end, cultured HepG2 hepatocytes, C2C12 myocytes, and 3T3-L1 adipocytes were treated with nontoxic concentrations of 12 selected flavonoids and expression of Δ4-, Δ5-, and Δ6-desaturases (DEGS1, FADS1, and FADS2, respectively) was determined. The flavonoids tested were more cytotoxic to HepG2 and 3T3-L1 than to C2C12 cells. In HepG2 cells, FADS1 was induced by quercetin and FADS2 expression was increased by daidzein, genistein, and pratensein treatment. DEGS1 was increased by apigenin, luteolin, orobol, and quercetin administration. In differentiated C2C12 cells, substances had no inducing effect or even lowered target gene expression. Pratensein induced both FADS1 and FADS2 in differentiated 3T3-L1 cells and DEGS1 was increased by treatment with apigenin, genistein, luteolin, orobol, and quercetin. In conclusion, pratensein may be an interesting test compound for further studies in vitro and in vivo on omega-3 synthesis since it induces its rate-limiting enzyme FADS2. Apigenin, luteolin, orobol, and quercetin induced DEGS1 and thereby possibly synthesis of proapoptotic CER in malignant HepG2 cells and 3T3-L1. In contrast, in benign C2C12 cells, they did not elevate mRNA steady state levels of DEGS1. That may partly explain the higher resistance of C2C12 cells against flavonoids compared to the other cell lines. By affecting tumor cells and nontumor cells differently, these flavonoids may be promising substances for further research regarding anticancer properties. © 2018 BioFactors, 44(5):485-495, 2018.

Quercetin Lowers Plasma Triglycerides Accompanied by White Adipose Tissue Browning in Diet-Induced Obese Mice

Obesity and dyslipidemia are major risk factors for the development of cardiovascular diseases (CVD). Quercetin, a natural flavonoid, lowers plasma triglycerides (TG) in human intervention studies, and its intake is associated with lower CVD risk. The aim of this study was to elucidate the mechanism by which quercetin lowers plasma TG levels in diet-induced obesity. C57Bl/6J mice received a high-fat diet (45% of calories derived from fat) with or without quercetin (0.1% w/w) for 12 weeks. Quercetin decreased plasma TG levels from nine weeks onwards (−19%, p < 0.05), without affecting food intake, body composition, or energy expenditure. Mechanistically, quercetin did not reduce intestinal fatty acid (FA) absorption. Rather, quercetin induced a slight reduction in liver Apob expression (−13%, p < 0.05), which suggests decreased very-low density lipoprotein-TG production. Interestingly, quercetin also markedly increased the uptake of [³H]oleate, which was derived from glycerol tri[³H]oleate-labeled lipoprotein-like particles by subcutaneous white adipose tissue (sWAT, +60%, p < 0.05). Furthermore, quercetin also markedly increased mRNA expression of Ucp1 (+229%, p < 0.05) and Elovl3 (+138%, p < 0.05), specifically in sWAT. Accordingly, only quercetin-treated animals showed uncoupling protein-1 protein-positive cells in sWAT, which is fully compatible with increased browning. Taken together, the TG-lowering effect of quercetin may, at least in part, be due to increased TG-derived FA uptake by sWAT as a consequence of browning.

Host: Microbiome co-metabolic processing of dietary polyphenols - An acute, single blinded, cross-over study with different doses of apple polyphenols in healthy subjects

Apples are one of the most commonly consumed fruits and their high polyphenol content is considered one of the most important determinants of their health-promoting activities. Here we studied the nutrikinetics of apple polyphenols by UHPLC-HRMS metabolite fingerprinting, comparing bioavailability when consumed in a natural or a polyphenol-enriched cloudy apple juice. Twelve men and women participated in an acute single blind controlled crossover study in which they consumed 250 mL of cloudy apple juice (CAJ), Crispy Pink apple variety, or 250 mL of the same juice enriched with 750 mg of an apple polyphenol extract (PAJ). Plasma and whole blood were collected at time 0, 1, 2, 3 and 5 h. Urine was collected at time 0 and 0-2, 2-5, 5-8, and 8-24 h after juice consumption. Faecal samples were collected from each individual during the study for 16S rRNA gene profiling. As many as 110 metabolites were significantly elevated following intake of polyphenol enriched cloudy apple juice, with large inter-individual variations. The comparison of the average area under the curve of circulating metabolites in plasma and in urine of volunteers consuming either the CAJ or the PAJ demonstrated a stable metabotype, suggesting that an increase in polyphenol concentration in fruit does not limit their bioavailability upon ingestion. Faecal bacteria were correlated with specific microbial catabolites derived from apple polyphenols. Human metabolism of apple polyphenols is a co-metabolic process between human encoded activities and those of our resident microbiota. Here we have identified specific blood and urine metabolic biomarkers of apple polyphenol intake and identified putative associations with specific genera of faecal bacteria, associations which now need confirmation in specifically designed mechanistic studies.

Cold exposure down-regulates immune response pathways in ferret aortic perivascular adipose tissue

Perivascular adipose tissue (PVAT) surrounds blood vessels and releases paracrine factors, such as cytokines, which regulate local inflammation. The inflammatory state of PVAT has an important role in vascular disease; a pro-inflammatory state has been related with atherosclerosis development, whereas an anti-inflammatory one is protective. Cold exposure beneficially affects immune responses and, could thus impact the pathogenesis of cardiovascular diseases. In this study, we investigated the effects of one-week of cold exposure at 4°C of ferrets on aortic PVAT (aPVAT) versus subcutaneous adipose tissue. Ferrets were used because of the similarity of their adipose tissues to those of humans. A ferret-specific Agilent microarray was designed to cover the complete ferret genome and global gene expression analysis was performed. The data showed that cold exposure altered gene expression mainly in aPVAT. Most of the regulated genes were associated with cell cycle, immune response and gene expression regulation, and were mainly down-regulated. Regarding the effects on immune response, cold acclimation decreased the expression of genes involved in antigen recognition and presentation, cytokine signalling and immune system maturation and activation. This immunosuppressive gene expression pattern was depot-specific, as it was not observed in the inguinal subcutaneous depot. Interestingly, this depression in immune response related genes was also evident in peripheral blood mononuclear cells (PBMC). In conclusion, these results reveal that cold acclimation produces an inhibition of immune response-related pathways in aPVAT, reflected in PBMC, indicative of an anti-inflammatory response, which can potentially be exploited for the enhancement or maintenance of cardiovascular health.

Supplementary Material to this article is available online at www.thrombosis-online.com.

Bidens pilosa Ethylene acetate extract can protect against L-NAME-induced hypertension on rats

BACKGROUND

Essential hypertension is mainly caused by endothelial dysfunction which results from nitric oxide (NO) deficiency. The present study was design to evaluate the protective effect of Bidens pilosa ethylene acetate extract (Bp) on L-NAME induced hypertension and oxidative stress in rats.

METHODS

Male Wistar rats were used to induce hypertension by the administration of L-NAME (a non-pecific nitric oxide inhibitor) (50 mg/kg/day). The others groups were receiving concomitantly L-NAME plus Bp extract (75 and 150 mg/kg/day) or losartan (25 mg/kg/day). All the treatments were given orally for 4 weeks. At the end of the treatment, the hemodynamic parameters were recorded using the direct cannulation method. The effects of the extract on lipid profile, kidney and liver functions as well as oxidative stress markers were evaluated by colorimetric method. Results were expressed as the mean ± SEM. The difference between the groups was compared using one-way analysis of variance (ANOVA) followed by the Duncan's post hoc test.

RESULTS

Animals receiving L-NAME presented high blood pressure, normal heart rate and lipid profile as well as NO depletion, liver and kidney injuries and oxidative stress. The concomitant treatment with L-NAME and Bp or losartan succeeded to prevent the raised of blood pressure and all the other injuries without affecting the heart rate.

CONCLUSION

These results confirm the antihypertensive effects of Bidens pilosa and highlight its protective properties in L-NAME model of hypertension in rat, probably due to the presence of Quercetin 3,3 '-dimethyl ether 7-0-β-D-glucopyranoside.

Transcriptional analysis of abdominal fat in chickens divergently selected on bodyweight at two ages reveals novel mechanisms controlling adiposity: validating visceral adipose tissue as a dynamic endocrine and metabolic organ

Background

Decades of intensive genetic selection in the domestic chicken (Gallus gallus domesticus) have enabled the remarkable rapid growth of today’s broiler (meat-type) chickens. However, this enhanced growth rate was accompanied by several unfavorable traits (i.e., increased visceral fatness, leg weakness, and disorders of metabolism and reproduction). The present descriptive analysis of the abdominal fat transcriptome aimed to identify functional genes and biological pathways that likely contribute to an extreme difference in visceral fatness of divergently selected broiler chickens.

Methods

We used the Del-Mar 14 K Chicken Integrated Systems microarray to take time-course snapshots of global gene transcription in abdominal fat of juvenile [1-11 weeks of age (wk)] chickens divergently selected on bodyweight at two ages (8 and 36 wk). Further, a RNA sequencing analysis was completed on the same abdominal fat samples taken from high-growth (HG) and low-growth (LG) cockerels at 7 wk, the age with the greatest divergence in body weight (3.2-fold) and visceral fatness (19.6-fold).

Results

Time-course microarray analysis revealed 312 differentially expressed genes (FDR ≤ 0.05) as the main effect of genotype (HG versus LG), 718 genes in the interaction of age and genotype, and 2918 genes as the main effect of age. The RNA sequencing analysis identified 2410 differentially expressed genes in abdominal fat of HG versus LG chickens at 7 wk. The HG chickens are fatter and over-express numerous genes that support higher rates of visceral adipogenesis and lipogenesis. In abdominal fat of LG chickens, we found higher expression of many genes involved in hemostasis, energy catabolism and endocrine signaling, which likely contribute to their leaner phenotype and slower growth. Many transcription factors and their direct target genes identified in HG and LG chickens could be involved in their divergence in adiposity and growth rate.

Conclusions

The present analyses of the visceral fat transcriptome in chickens divergently selected for a large difference in growth rate and abdominal fatness clearly demonstrate that abdominal fat is a very dynamic metabolic and endocrine organ in the chicken. The HG chickens overexpress many transcription factors and their direct target genes, which should enhance in situ lipogenesis and ultimately adiposity. Our observation of enhanced expression of hemostasis and endocrine-signaling genes in diminished abdominal fat of LG cockerels provides insight into genetic mechanisms involved in divergence of abdominal fatness and somatic growth in avian and perhaps mammalian species, including humans.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-017-4035-5) contains supplementary material, which is available to authorized users.

Effects of a wide range of dietary nicotinamide riboside (NR) concentrations on metabolic flexibility and white adipose tissue (WAT) of mice fed a mildly obesogenic diet

SCOPE

Metabolic flexibility is the ability to switch metabolism between carbohydrate oxidation (CHO) and fatty acid oxidation (FAO) and is a biomarker for metabolic health. The effect on metabolic health of nicotinamide riboside (NR) as an exclusive source of vitamin B3 is unknown and is examined here for a wide range of NR.

DESIGN AND METHODS

Nine-week-old male C57BL/6JRcc mice received a semi-purified mildly obesogenic (40 en% fat) diet containing 0.14% L-tryptophan and either 5, 15, 30, 180, or 900 mg NR per kg diet for 15 weeks. Body composition and metabolic parameters were analyzed. Metabolic flexibility was measured using indirect calorimetry. Gene expression in epididymal white adipose tissue (eWAT) was measured using qRT-PCR .

RESULTS

The maximum delta respiratory exchange ratio when switching from CHO to FAO (maxΔRERCHO1→FAO ) and when switching from FAO to CHO (maxΔRERFAO→CHO2 ) were largest in 30 mg NR per kg diet (30NR). In eWAT, the gene expression of Pparγ, a master regulator of adipogenesis, and of Sod2 and Prdx3, two antioxidant genes, were significantly upregulated in 30NR compared to 5NR.

CONCLUSION

30NR is most beneficial for metabolic health, in terms of metabolic flexibility and eWAT gene expression, of mice on an obesogenic diet.

Effects of a six-week intraduodenal supplementation with quercetin on liver lipid metabolism and oxidative stress in peripartal dairy cows

The purpose of this study was to evaluate possible effects of quercetin (Q) on liver lipid metabolism and antioxidative status in periparturient dairy cows. The periparturient period is associated with enormous metabolic changes for dairy cows. Energy needs for incipient lactation are too high to be balanced by feed intake, leading to negative energy balance and body fat mobilization. It has been estimated that this leads to the development of fatty liver in about 50% of cows, which are at high risk for disease. Furthermore, the antioxidative status of these cows may be impaired. Quercetin is a plant flavonoid having hepatoprotective and antioxidative potential and the ability to reduce liver lipid accumulation in monogastric animals. Little information is available in regard to these effects in ruminants. To prevent microbial Q degradation in the rumen, Q was administered via a duodenal fistula to improve systemic availability. Five cows of the Q-treated group received, daily, 100 mg of quercetin dehydrate/kg BW in a 0.9% sodium chloride solution from d -20 until d 20 relative to calving, whereas 5 control (CTR) cows received only a sodium chloride solution. Blood samples were taken weekly and liver biopsies were performed in wk -4, -2, and 3 relative to calving. Cows treated with Q showed a tendency ( = 0.082) for lower liver fat content compared with CTR cows. Liver glycogen, glutathione concentrations, and relative mRNA abundance of genes related to hepatic lipid metabolism and antioxidative status as well as parameters of antioxidative status in plasma were not affected ( > 0.1) by Q supplementation. In conclusion, liver fat content in dairy cows tended to be reduced by Q supplementation, but potential underlying mechanisms remain unclear because analyzed parameters related to hepatic lipid metabolism and antioxidative defense were not altered by Q supplementation.

Metabolic Response of Visceral White Adipose Tissue of Obese Mice Exposed for 5 Days to Human Room Temperature Compared to Mouse Thermoneutrality

Housing of laboratory mice at room temperature (22°C) might be considered a constant cold stress, which induces a thermogenic program in brown adipose tissue (BAT). However, the early adaptive response of white adipose tissue (WAT), the fat storage organ of the body, to a change from thermoneutrality to room temperature is not known. This was investigated here for various WAT depots, focusing on epididymal WAT (eWAT), widely used as reference depot. Male adult diet-induced obese (DIO) C57BL/6JOlaHsd mice housed at thermoneutrality (29°C), were for 5 days either switched to room temperature (22°C) or remained at thermoneutrality. Energy metabolism was continuously measured using indirect calorimetry. At the end of the study, serum metabolomics and WAT transcriptomics were performed. We confirmed activation of the thermogenic program in 22°C housed mice. Body weight and total fat mass were reduced. Whole body energy expenditure (EE) was increased, with a higher fatty acid to carbohydrate oxidation ratio and increased serum acylcarnitine levels, while energy intake was not significantly different between the two groups. Transcriptome analysis of eWAT identified tissue remodeling and inflammation as the most affected processes. Expression of pro-inflammatory M1 macrophage-related genes, and M1 over M2 macrophage ratio were decreased, which might be linked to an increased insulin sensitivity. Markers of thermogenesis were not altered in eWAT. Decreased expression of tryptophan hydroxylase 2 (Tph2) and cholecystokinin (Cck) might represent altered neuroendocrine signaling. eWAT itself does not show increased fatty acid oxidation. The three measured WATs, epididymal, mesenteric, and retroperitoneal, showed mainly similar responses; reduced inflammation (s100a8), decreased carbohydrate oxidation, and no or small differences in fatty acid oxidation. However, Ucp1 was only expressed and increased in rWAT in 22°C housed mice. Cck expression was decreased in the three WATs, significantly in eWAT and rWAT, in contrast to Tph2, which was decreased in eWAT while not expressed in mWAT and rWAT. Our data show that tissue remodeling, inflammation and neuroendocrine signaling are early responses in WAT to a moderate decrease in environmental temperature.

A Low Dose of Dietary Quercetin Fails to Protect against the Development of an Obese Phenotype in Mice

The purpose of this study was to examine the effect of a 40% high-fat diet (HFD) supplemented with a dietary attainable level of quercetin (0.02%) on body composition, adipose tissue (AT) inflammation, Non-Alcoholic Fatty-Liver Disease (NAFLD), and metabolic outcomes. Diets were administered for 16 weeks to C57BL/6J mice (n = 10/group) beginning at 4 weeks of age. Body composition and fasting blood glucose, insulin, and total cholesterol concentrations were examined intermittently. AT and liver mRNA expression (RT-PCR) of inflammatory mediators (F4/80, CD206 (AT only), CD11c (AT only) TLR-2 (AT only), TLR-4 (AT only), MCP-1, TNF-α, IL-6 (AT only), and IL-10 (AT only)) were measured along with activation of NFκB-p65, and JNK (western blot). Hepatic lipid accumulation, gene expression (RT-PCR) of hepatic metabolic markers (ACAC1, SREBP-1, PPAR-γ), protein content of Endoplasmic Reticulum (ER) Stress markers (BiP, phosphorylated and total EIF2α, phosphorylated and total IRE1α, CHOP), and hepatic oxidative capacity were assessed (western blot). Quercetin administration had no effect at mitigating increases in visceral AT, AT inflammation, hepatic steatosis, ER Stress, decrements in hepatic oxidative capacity, or the development of insulin resistance and hypercholesterolemia. In conclusion, 0.02% quercetin supplementation is not an effective therapy for attenuating HFD-induced obesity development. It is likely that a higher dose of quercetin supplementation is needed to elicit favorable outcomes in obesity.

Serum Metabolomics Analysis of Quercetin against Acrylamide-Induced Toxicity in Rats

The current study aimed to investigate whether quercetin plays a protective role in acrylamide (AA)-induced toxicity using a metabolomics approach. Rats were randomly divided into groups as follows: control, treated with AA [5 mg/kg body weight (bw)], treated with different dosages of quercetin (10 and 50 mg/kg bw, respectively), and treated with two dosages of quercetin plus AA. After a 16 week treatment, rat serum was collected for metabolomics analysis. Biochemical tests and examination of liver histopathology were further conducted to verify metabolic alterations. Twelve metabolites were identified for which intensities were significantly changed (increased or reduced) as a result of the treatment. These metabolites included isorhamnetin, citric acid, pantothenic acid, isobutyryl-l-carnitine, eicosapentaenoic acid, docosahexaenoic acid, sphingosine 1-phosphate, lysoPC(20:4), lysoPC(22:6), lysoPE(20:3), undecanedioic acid, and dodecanedioic acid. The results indicate that quercetin (50 mg/kg bw) exerts partial protective effects on AA-induced toxicity by reducing oxidative stress, protecting the mitochondria, and regulating lipid metabolism.

Obese Mice Fed a Diet Supplemented with Enzyme-Treated Wheat Bran Display Marked Shifts in the Liver Metabolome Concurrent with Altered Gut Bacteria

BACKGROUND

Enzyme-treated wheat bran (ETWB) contains a fermentable dietary fiber previously shown to decrease liver triglycerides (TGs) and modify the gut microbiome in mice. It is not clear which mechanisms explain how ETWB feeding affects hepatic metabolism, but factors (i.e., xenometabolites) associated with specific microbes may be involved.

OBJECTIVE

The objective of this study was to characterize ETWB-driven shifts in the cecal microbiome and to identify correlates between microbial changes and diet-related differences in liver metabolism in diet-induced obese mice that typically display steatosis.

METHODS

Five-week-old male C57BL/6J mice fed a 45%-lard-based fat diet supplemented with ETWB (20% wt:wt) or rapidly digestible starch (control) (n = 15/group) for 10 wk were characterized by using a multi-omics approach. Multivariate statistical analysis was used to identify variables that were strong discriminators between the ETWB and control groups.

RESULTS

Body weight and liver TGs were decreased by ETWB feeding (by 10% and 25%, respectively; P < 0.001), and an index of liver reactive oxygen species was increased (by 29%; P < 0.01). The cecal microbiome showed an increase in Bacteroidetes (by 42%; P < 0.05) and a decrease in Firmicutes (by 16%; P < 0.05). Metabolites that were strong discriminators between the ETWB and control groups included decreased liver antioxidants (glutathione and α-tocopherol); decreased liver carbohydrate metabolites, including glucose; lower hepatic arachidonic acid; and increased liver and plasma β-hydroxybutyrate. Liver transcriptomics revealed key metabolic pathways affected by ETWB, especially those related to lipid metabolism and some fed- or fasting-regulated genes.

CONCLUSIONS

Together, these changes indicate that dietary fibers such as ETWB regulate hepatic metabolism concurrently with specific gut bacteria community shifts in C57BL/6J mice. It is proposed that these changes may elicit gut-derived signals that reach the liver via enterohepatic circulation, ultimately affecting host liver metabolism in a manner that mimics, in part, the fasting state.

Breast milk nutrient content and infancy growth

Aim

Benefits of human breast milk (HM) in avoiding rapid infancy weight gain and later obesity could relate to its nutrient content. We tested the hypothesis that differential HM total calorie content (TCC) or macronutrient contents may be associated with infancy growth.

Methods

HM hindmilk samples were collected at ages 4–8 weeks from 614 mothers participating in a representative birth cohort, with repeated infancy anthropometry. HM triglyceride (fat), lipid analytes and lactose (carbohydrate) were measured by ¹H‐NMR, and protein content by the Dumas method. TCC and %macronutrients were determined.

Results

In 614 HM samples, fat content was as follows: [median(IQR)]: 2.6 (1.7–3.6) g/100 mL, carbohydrate: 8.6 (8.2–8.8) g/100 mL, protein: 1.2 (1.1–1.2) g/100 mL; TCC: 61.8 (53.7–71.3) kcal/100 mL. HM of mothers exclusively breast feeding vs. mixed feeding was more calorific with higher %fat, lower %carbohydrate and lower %protein. Higher HM TCC was associated with lower 12‐months body mass index (BMI)/adiposity, and lower 3–12 months gains in weight/BMI. HM %fat was inversely related to 3–12 months gains in weight, BMI and adiposity, whereas %carbohydrate was positively related to these measures. HM %protein was positively related to 12‐months BMI.

Conclusion

HM analysis showed wide variation in %macronutrients. Although data on milk intakes were unavailable, our findings suggest functional relevance of HM milk composition to infant growth.

Metabonomic analysis of the protective effect of quercetin on the toxicity induced by mixture of organophosphate pesticides in rat urine

The present study aims to investigate the protective effect of quercetin against the joint toxic action induced by the mixture of four organophosphate pesticides (mixture-OPs) (dimethoate, acephate, dichlorvos, and phorate) at their corresponding no observed adverse effect level (NOAEL) using metabonomics. Rats were randomly divided into control, quercetin-treated, mixture-OPs-treated, and quercetin plus mixture-OPs-treated groups. Mixture-OPs and quercetin were given to the rats daily through drinking water and intragastric administration, respectively, for 90 days. The metabonomic profiles of rat urine were analyzed using ultra-performance liquid chromatography–mass spectrometry (UPLC/MS). The 14 metabolites significantly changed in the treatment groups compared with the control group, including the biomarkers of OPs exposure (dimethylphosphate, dimethyldithiophosphate, diethylphosphate) and the metabolites of quercetin (quercetin and isorhamnetina). The intensities of gentisic acid, creatinine, suberic acid, hippuric acid, uric acid, and citric acid significantly decreased, whereas the intensities of 7-methylguanine, estrone sulfate, and cholic acid significantly increased, in the mixture-OPs-treated group compared with the control group ( p < 0.01). The variation tendency of the aforementioned metabolites was significantly ameliorated in the high-dose quercetin (50 mg/(kg bw day)) plus mixture-OPs-treated group compared with the mixture-OPs-treated group ( p < 0.05). However, the intensities of these metabolites in the high-dose quercetin plus mixture-OPs-treated group were still significantly different from those of the control group ( p < 0.05). Results indicated that high dose of quercetin elicits a partial protective effect on the toxicity induced by mixture-OPs, including fatty acid and energy metabolism, antioxidant defense system, DNA damage, and liver and kidney function.

Non-alcoholic steatohepatitis: emerging molecular targets and therapeutic strategies

Non-alcoholic fatty liver disease - the most common chronic liver disease - encompasses a histological spectrum ranging from simple steatosis to non-alcoholic steatohepatitis (NASH). Over the next decade, NASH is projected to be the most common indication for liver transplantation. The absence of an effective pharmacological therapy for NASH is a major incentive for research into novel therapeutic approaches for this condition. The current focus areas for research include the modulation of nuclear transcription factors; agents that target lipotoxicity and oxidative stress; and the modulation of cellular energy homeostasis, metabolism and the inflammatory response. Strategies to enhance resolution of inflammation and fibrosis also show promise to reverse the advanced stages of liver disease.

Effects of rutin and buckwheat seeds on energy metabolism and methane production in dairy cows

Flavonoids are secondary plant metabolites with several health promoting effects. As dairy cows often suffer from metabolic imbalance and health problems, interest is growing in health improvements by plant substances such as flavonoids. Our group has recently shown that the flavonoids quercetin and rutin (a glucorhamnoside of quercetin) are bioavailable in cows when given via a duodenal fistula or orally, respectively, affect glucose metabolism, and have beneficial effects on liver health. Furthermore, flavonoids may reduce rumen methane production in vitro through their antibacterial properties. To test the hypothesis that rutin has effects on energy metabolism, methane production, and production performance in dairy cows, we fed rutin trihydrate at a dose of 100mg/kg of body weight to a group of 7 lactating dairy cows for 2 wk in a crossover design. In a second experiment, 2 cows were fed the same ration but were supplemented with buckwheat seeds (Fagopyrum tartaricum), providing rutin at a dose comparable to the first experiment. Two other cows receiving barley supplements were used as controls in a change-over mode. Blood samples were taken weekly and respiration measurements were performed at the end of each treatment. Supplementation of pure rutin, but not of rutin contained in buckwheat seeds, increased the plasma quercetin content. Methane production and milk yield and composition were not affected by rutin treatment in either form. Plasma glucose, β-hydroxybutyrate, and albumin were increased by pure rutin treatment, indicating a possible metabolic effect of rutin on energy metabolism of dairy cows. In addition, we did not show that in vivo ruminal methane production was reduced by rutin. In conclusion, we could not confirm earlier reports on in vitro methane reduction by rutin supplementation in dairy cows in established lactation.

Natural antioxidants for non-alcoholic fatty liver disease: molecular targets and clinical perspectives

Non-alcoholic steatohepatitis (NASH), the progressive form of non-alcoholic fatty liver disease (NAFLD), is emerging as a main health problem in industrialized countries. Lifestyle modifications are effective in the treatment of NAFLD; however, the long-term compliance is low. Therefore, several pharmacological treatments have been proposed but none has shown significant efficacy or long-term safety. Natural polyphenols are a heterogeneous class of polyphenolic compounds contained in vegetables, which are being proposed for the treatment of different metabolic disorders. Although the beneficial effect of these compounds has traditionally related to their antioxidant properties, they also exert several beneficial effects on hepatic and extra-hepatic glucose and lipid homeostasis. Furthermore, natural polyphenols exert antifibrogenic and antitumoural effects in animal models, which appear relevant from a clinical point of view because of the association of NASH with cirrhosis and hepatocellular carcinoma. Several polyphenols, such anthocyanins, curcumin and resveratrol and those present in coffee, tea, soy are available in the diet and their consumption can be proposed as part of a healthy diet for the treatment of NAFLD. Other phenolic compounds, such as silymarin, are commonly consumed worldwide as nutraceuticals or food supplements. Natural antioxidants are reported to have beneficial effects in preclinical models of NAFLD and in pilot clinical trials, and thus need clinical evaluation. In this review, we summarize the existing evidence regarding the potential role of natural antioxidants in the treatment of NAFLD and examine possible future clinical applications.

Metabonomic analysis of quercetin against the toxicity of chronic exposure to a mixture of four organophosphate pesticides in rat plasma

1. A metabonomics approach was performed to investigate the effect of quercetin on the toxicity of chronic exposure to a mixture of four organophosphate pesticides (OPs) at their corresponding no-observed-adverse-effect level (NOAEL). The rats were divided into six groups (n = 10/group): control, two different doses of quercetin, OPs mixture and different doses of quercetin plus OPs mixture-treated groups. 2. Nine metabolites, including two quercetin metabolites and seven endogenous metabolites were identified in plasma. The intensities of metabolites significantly changed in the OP mixture-treated group compared with the control group (p < 0.01), such as lysoPE (16:0/0:0), lysoPC (17:0/0:0), lysoPC (15:0/0:0) and 4-pyridoxic acid, significantly increased; by contrast, the intensities of arachidonic acid and citric acid significantly decreased. Anomalous intensity changes in aforementioned metabolites were alleviated in the OP mixture plus 50 mg/kgċbw/d quercetin-treated group compared with the OP mixture-treated group (p < 0.05). 3. The results indicated that quercetin elicited partial protective effects against the toxicity induced by a mixture of OPs, which include regulation of lipid metabolism, improvement of tricarboxylic acid (TCA) cycle disorders, enhancement of antioxidant defence system to protect the liver.

Salicornia herbacea prevents weight gain and hepatic lipid accumulation in obese ICR mice fed a high-fat diet

BACKGROUND

Foods that are rich in fat and or sodium chloride promote obesity and associated diseases, whereas intake of dietary fiber averts obesity development. Salicornia herbacea (SH) is a rich source of dietary fiber and high in sodium chloride; therefore, we investigated whether replacing common salt with SH in a high-fat diet could prevent obesity development.

RESULTS

Mice were divided into five groups: group ND was fed a normal diet, group HD was fed a high-fat diet, group HD-NaCl was fed a high fat diet with sodium chloride 10 g kg(-1) , group HD-CL was fed a high-fat diet with cellulose 30 g kg(-1) and group HD-SH was fed a high-fat diet with SH powder 50 g kg(-1) . The amount of sodium chloride and cellulose added in the respective diet was equivalent to their amount in SH. Data from our study showed that, SH supplementation significantly decreased body weight gain, liver weight, hepatic triglyceride, serum leptin and insulin, along with the mRNA level of key lipid anabolic genes such as SREBP-1c, PPARγ and FAS compared to the HD group.

CONCLUSION

The results of this study demonstrated that SH is a potential natural anti-obesity agent that can be used in place of sodium chloride.

The direction of cross affects [corrected] obesity after puberty in male but not female offspring

BACKGROUND

We investigated parent-of-origin and allele-specific expression effects on obesity and hepatic gene expression in reciprocal crosses between the Berlin Fat Mouse Inbred line (BFMI) and C57Bl/6NCrl (B6N).

RESULTS

We found that F1-males with a BFMI mother developed 1.8 times more fat mass on a high fat diet at 10 weeks than F1-males of a BFMI father. The phenotype was detectable from six weeks on and was preserved after cross-fostering. RNA-seq data of liver provided evidence for higher biosynthesis and elongation of fatty acids (p = 0.00635) in obese male offspring of a BFMI mother versus lean offspring of a BFMI father. Furthermore, fatty acid degradation (p = 0.00198) and the peroxisome pathway were impaired (p = 0.00094). The circadian rhythm was affected as well (p = 0.00087). Among the highest up-regulated protein coding genes in obese males were Acot4 (1.82 fold, p = 0.022), Cyp4a10 (1.35 fold, p = 0.026) and Cyp4a14 (1.32 fold, p = 0.012), which hydroxylize fatty acids and which are known to be increased in liver steatosis. Obese males showed lower expression of the genetically imprinted and paternally expressed 3 (Peg3) gene (0.31 fold, p = 0.046) and higher expression of the androgen receptor (Ar) gene (2.38 fold, p = 0.068). Allelic imbalance was found for expression of ATP-binding cassette transporter gene Abca8b. Several of the differentially expressed genes contain estrogen response elements.

CONCLUSIONS

Parent-of-origin effects during gametogenesis and/or fetal development in an obese mother epigenetically modify the transcription of genes that lead to enhanced fatty acid synthesis and impair β-oxidation in the liver of male, but not female F1 offspring. Down-regulation of Peg3 could contribute to trigger this metabolic setting. At puberty, higher amounts of the androgen receptor and altered access to estrogen response elements in affected genes are likely responsible for male specific expression of genes that were epigenetically triggered. A suggestive lack of estrogen binding motifs was found for highly down-regulated genes in adult hepatocytes of obese F1 males (p = 0.074).

Direct comparison of metabolic health effects of the flavonoids quercetin, hesperetin, epicatechin, apigenin and anthocyanins in high-fat-diet-fed mice

Dietary flavonoid intake is associated with reduced risk of cardiovascular diseases, possibly by affecting metabolic health. The relative potency of different flavonoids in causing beneficial effects on energy and lipid metabolism has not been investigated. Effects of quercetin, hesperetin, epicatechin, apigenin and anthocyanins in mice fed a high-fat diet (HF) for 12 weeks were compared, relative to normal-fat diet. HF-induced body weight gain was significantly lowered by all flavonoids (17-29 %), but most by quercetin. Quercetin significantly lowered HF-induced hepatic lipid accumulation (71 %). Mesenteric adipose tissue weight and serum leptin levels were significantly lowered by quercetin, hesperetin and anthocyanins. Adipocyte cell size and adipose tissue inflammation were not affected. The effect on body weight and composition could not be explained by individual significant effects on energy intake, energy expenditure or activity. Lipid metabolism was not changed as measured by indirect calorimetry or expression of known lipid metabolic genes in liver and white adipose tissue. Hepatic expression of Cyp2b9 was strongly downregulated by all flavonoids. In conclusion, all flavonoids lowered parameters of HF-induced adiposity, with quercetin being most effective.

A Difference in Fatty Acid Composition of Isocaloric High-Fat Diets Alters Metabolic Flexibility in Male C57BL/6JOlaHsd Mice

Poly-unsaturated fatty acids (PUFAs) are considered to be healthier than saturated fatty acids (SFAs), but others postulate that especially the ratio of omega-6 to omega-3 PUFAs (n6/n3 ratio) determines health. Health can be determined with biomarkers, but functional health status is likely better reflected by challenge tests that assess metabolic flexibility. The aim of this study was to determine the effect of high-fat diets with different fatty acid compositions, but similar n6/n3 ratio, on metabolic flexibility. Therefore, adult male mice received isocaloric high-fat diets with either predominantly PUFAs (HFpu diet) or predominantly SFAs (HFs diet) but similar n6/n3 ratio for six months, during and after which several biomarkers for health were measured. Metabolic flexibility was assessed by the response to an oral glucose tolerance test, a fasting and re-feeding test and an oxygen restriction test (OxR; normobaric hypoxia). The latter two are non-invasive, indirect calorimetry-based tests that measure the adaptive capacity of the body as a whole. We found that the HFs diet, compared to the HFpu diet, increased mean adipocyte size, liver damage, and ectopic lipid storage in liver and muscle; although, we did not find differences in body weight, total adiposity, adipose tissue health, serum adipokines, whole body energy balance, or circadian rhythm between HFs and HFpu mice. HFs mice were, furthermore, less flexible in their response to both fasting- re-feeding and OxR, while glucose tolerance was indistinguishable. To conclude, the HFs versus the HFpu diet increased ectopic fat storage, liver damage, and mean adipocyte size and reduced metabolic flexibility in male mice. This study underscores the physiological relevance of indirect calorimetry-based challenge tests.

Effect of Natural Polyphenols on CYP Metabolism: Implications for Diseases

Cytochromes P450 (CYPs) are a large group of hemeproteins located on mitochondrial membranes or the endoplasmic reticulum. They play a crucial role in the metabolism of endogenous and exogenous molecules. The activity of CYP is associated with a number of factors including redox potential, protein conformation, the accessibility of the active site by substrates, and others. This activity may be potentially modulated by a variety of small molecules. Extensive experimental data collected over the past decade point at the active role of natural polyphenols in modulating the catalytic activity of CYP. Polyphenols are widespread micronutrients present in human diets of plant origin and in medicinal herbs. These compounds may alter the activity of CYP either via direct interactions with the enzymes or by affecting CYP gene expression. The polyphenol-CYP interactions may significantly alter the pharmacokinetics of drugs and thus influence the effectiveness of chemical therapies used in the treatment of different types of cancers, diabetes, obesity, and cardiovascular diseases (CVD). CYPs are involved in the oxidation and activation of external carcinogenic agents, in which case the inhibition of the CYP activity is beneficial for health. CYPs also support detoxification processes. In this case, it is the upregulation of CYP genes that would be favorable for the organism. A CYP enzyme aromatase catalyzes the formation of estrone and estradiol from their precursors. CYPs also catalyze multiple reactions leading to the oxidation of estrogen. Estrogen signaling and oxidative metabolism of estrogen are associated with the development of cancer. Thus, polyphenol-mediated modulation of the CYP's activity also plays a vital role in estrogen carcinogenesis. The aim of the present review is to summarize the data collected over the last five to six years on the following topics: (1) the mechanisms of the interactions of CYP with food constituents that occur via the direct binding of polyphenols to the enzymes and (2) the mechanisms of the regulation of CYP gene expression mediated by polyphenols. The structure-activity relationship relevant to the ability of polyphenols to affect the activity of CYP is analyzed. The application of polyphenol-CYP interactions to diseases is discussed.

Effects of a 6-wk intraduodenal supplementation with quercetin on energy metabolism and indicators of liver damage in periparturient dairy cows

Periparturient dairy cows experience metabolic challenges that result in a negative energy balance (EB) and a range of postpartum health problems. To compensate for the negative EB, cows mobilize fatty acids from adipose tissues, which can lead to fatty liver disease, a periparturient metabolic disorder. Flavonoids, such as quercetin (Q), are polyphenolic substances found in all higher plants and have hepatoprotective potential and the ability to prevent or reduce lipid accumulation in the liver. In ruminants, few studies on the metabolic effects of Q are available, and thus this study was conducted to determine whether Q has beneficial effects on EB, lipid metabolism, and hepatoprotective effects in periparturient dairy cows. Quercetin was supplemented intraduodenally to circumvent Q degradation in the rumen. Cows (n=10) with duodenal fistulas were monitored for 7wk. Beginning 3wk before expected calving, 5 cows were treated with 100mg of quercetin dihydrate per kilogram of body weight daily in a 0.9% sodium chloride solution for a total period of 6wk, whereas the control cows received only the sodium chloride solution. The plasma flavonoid levels were higher in the Q-treated cows than in the control cows. A tendency for higher postpartum (pp) than antepartum (ap) plasma flavonoid levels was observed in the Q-treated cows than in the controls, which was potentially caused by a reduced capacity to metabolize Q. However, the metabolic status of the Q-treated cows did not differ from that of the control cows. The pp increases in plasma aspartate aminotransferase and glutamate dehydrogenase activities were less in the Q-treated cows than in the control cows. The Q had no effect on energy expenditures, but from ap to pp the cows had a slight decline in respiratory quotients. Irrespective of the treatment group, the oxidation of fat peaked after calving, suggesting that the increase occurred because of an increased supply of fatty acids from lipomobilization. In conclusion, supplementation with Q resulted in lower pp plasma aminotransferase and glutamate dehydrogenase, which indicated reduced liver damage. However, the direct effects of Q on the liver and the implications for animal performance remain to be investigated.

Reduced oxidative stress contributes to the lipid lowering effects of isoquercitrin in free fatty acids induced hepatocytes

Oxidative stress interferes with hepatic lipid metabolism at various levels ranging from benign lipid storage to so-called second hit of inflammation activation. Isoquercitrin (IQ) is widely present flavonoid but its effects on hepatic lipid metabolism remain unknown. We used free fatty acids (FFA) induced lipid overload and oxidative stress model in two types of liver cells and measured cell viability, intracellular lipids, and reactive oxygen species (ROS) within hepatocytes. In addition, Intracellular triglycerides (TG), superoxide dismutase (SOD), and malondialdehyde (MDA) were examined. A novel in vitro model was used to evaluate correlation between lipid lowering and antioxidative activities. Furthermore, 34 major cytokines and corresponding ROS levels were analyzed in FFA/LPS induced coculture model between hepatocytes and Kupffer cells. At molecular level AMPK pathway was elucidated. We showed that IQ attenuated FFA induced lipid overload and ROS within hepatocytes. Further, IQ reversed FFA induced increase in intracellular TG SOD and MDA. It was shown that antioxidative activity of IQ correlates with its lipid lowering potentials. IQ reversed major proinflammatory cytokines and oxidative stress in FFA/LPS induced coculture model. Finally, AMPK pathway was found responsible for metabolic benefits at molecular level. IQ strikingly manifests antioxidative and related lipid lowering activities in hepatocytes.