Regulation of HepG2 cell apolipoprotein B metabolism by the citrus flavanones hesperetin and naringenin

Orange juice intake and lipid profile: a systematic review and meta-analysis of randomised controlled trials

Dyslipidaemia is a metabolic anomaly which has been related to numerous morbidities. Orange juice (OJ) is a popular flavonoid-rich drink consumed worldwide. Due to the existing controversies regarding its impact on blood lipids, we decided to investigate the impact of OJ supplementation on lipid profile parameters. Major scientific databases (Cochrane library, Scopus, PubMed and Embase) were searched. Pooled effects sizes were reported as weighted mean difference (WMD) and 95 % confidence intervals (CIs). Out of 6334 articles retrieved by the initial search, 9 articles met our inclusion criteria. Overall, supplementation with OJ did not exert any significant effects on blood levels of TG (WMD −1·53 mg/dl, 95 % CI −6·39, 3·32, P = 0·536), TC (WMD −5·91 mg/dl, 95 % CI −13·26, 1·43, P = 0·114) or HDL-C (WMD 0·61 mg/ dl, 95 % CI −0·61, 1·82, P = 0·333). OJ consumption did reduce LDL-C levels significantly (WMD −8·35 mg/dl, 95 % CI −15·43, −1·26, P = 0·021). Overall, we showed that the consumption of OJ may not be beneficial in improving serum levels of TG, TC or HDL-C. Contrarily, we showed that daily intake of OJ, especially more than 500 ml/d, might be effective in reducing LDL-C levels. In the light of the existing inconsistencies, we propose that further high-quality interventions be conducted in order to make a solid conclusion.

Hesperetin-Between the Ability to Diminish Mono- and Polymicrobial Biofilms and Toxicity

Hesperetin is the aglycone of citrus flavonoid hesperidin. Due to the limited information regarding hesperetin antimicrobial potential and emerging need for novel antimicrobials, we have studied its antimicrobial activity (microdilution assay), antibiofilm activity with different assays in two models (mono- and polymicrobial biofilm), and toxicity (MTT and brine shrimp lethality assays). Hesperetin inhibited growth of all Candida isolates (minimal inhibitory concentration, MIC, 0.165 mg/mL), while it’s inhibitory potential towards Staphylococcus aureus was lower (MIC 4 mg/mL). Hesperetin (0.165 mg/mL) reduced ability of Candida to form biofilms and moderately reduced exopolysaccharide levels in biofilm matrix. Effect on the eradication of 24 h old C. albicans biofilms was promising at 1.320 mg/mL. Inhibition of staphylococcal biofilm formation required higher concentrations of hesperetin (<50% inhibition with MIC 4 mg/mL). Establishment of polymicrobial C. albicans-S. aureus biofilm was significantly inhibited with the lowest examined hesperetin concentration (1 mg/mL) in crystal violet and CFU assays. Hesperetin toxicity was examined towards MRC-5 fibroblasts (IC50 0.340 mg/mL) and in brine shrimp lethality assay (LC50 > 1 mg/mL). Hesperetin is efficient in combating growth and biofilm formation of Candida species. However, its antibacterial application should be further examined due to the cytotoxic effects provoked in the antibacterial concentrations.

New Benzil and Isoflavone Derivatives with Cytotoxic and NO Production Inhibitory Activities from Placolobium vietnamense

The phytochemical investigation of Placolobium vietnamense stems led to the isolation of a new isoflavone derivative (1) and three new benzil derivatives (2–4), together with four known pyranoisoflavones (5–8). The structures of all isolated compounds were determined on the basis of extensive spectroscopic analyses, including NMR and HRMS spectral data, as well as comparison of their spectroscopic data with those reported in the literature. The cytotoxicity of all isolated compounds was assessed against the human liver hepatocellular carcinoma (Hep G2) cell line, and compound 1 displayed the most significant cytotoxicity with an IC₅₀ value of 8.0 μM. Furthermore, all isolated compounds were also tested for their inhibitory activity against NO production in RAW 264.7 macrophages. Of these, compound 1 exhibited the strongest inhibitory efficacy against the LPS-induced NO production with the IC₅₀ value of 13.7 μM.

A Pilot Study Comparing the Effects of Consuming 100% Orange Juice or Sucrose-Sweetened Beverage on Risk Factors for Cardiometabolic Disease in Women

Overconsumption of sugar-sweetened beverages increases risk factors associated with cardiometabolic disease, in part due to hepatic fructose overload. However, it is not clear whether consumption of beverages containing fructose as naturally occurring sugar produces equivalent metabolic dysregulation as beverages containing added sugars. We compared the effects of consuming naturally-sweetened orange juice (OJ) or sucrose-sweetened beverages (sucrose-SB) for two weeks on risk factors for cardiometabolic disease. Healthy, overweight women (n = 20) were assigned to consume either 3 servings of 100% orange juice or sucrose-SB/day. We conducted 16-hour serial blood collections and 3-h oral glucose tolerance tests during a 30-h inpatient visit at baseline and after the 2-week diet intervention. The 16-h area under the curve (AUC) for uric acid increased in subjects consuming sucrose-SB compared with subjects consuming OJ. Unlike sucrose-SB, OJ did not significantly increase fasting or postprandial lipoproteins. Consumption of both beverages resulted in reductions in the Matsuda insulin sensitivity index (OJ: -0.40 ± 0.18, p = 0.04 within group; sucrose-SB: -1.0 ± 0.38, p = 0.006 within group; p = 0.53 between groups). Findings from this pilot study suggest that consumption of OJ at levels above the current dietary guidelines for sugar intake does not increase plasma uric acid concentrations compared with sucrose-SB, but appears to lead to comparable decreases of insulin sensitivity.

Impact of orange juice consumption on cardiovascular disease risk factors: a systematic review and meta-analysis of randomized-controlled trials

Cardiovascular disease (CVD) is the greatest cause of premature death and disability globally. Numerous therapeutic strategies have been developed to improve and prevent the adverse cardiovascular events, including nutritional approaches. This systematic review and meta-analysis summarized the evidence on orange juice consumption on CVD risk factors. Four databases were searched up to September 2020. Ten randomized controlled trials were included in the final analysis. Pooled results demonstrated a significant effect of orange juice on glucose (WMD: -2.92 mg/dl, 95% CI: -5.327, -0.530, p = 0.017), insulin (WMD: -1.229 μU/ml, 95% CI: -2.083, -0.374, p = 0.005), HOMA-IR (WMD: -0.464, 95% CI: -0.747, -0.181, p = 0.001), total cholesterol (WMD: -9.84 mg/dl, 95% CI: -15.43, -4.24, p = 0.001), LDL-C (WMD: -9.14 mg/dl, 95% CI: -15.79, -2.49, p = 0.007), and CRP (WMD: -0.467 mg/l, 95% CI: -0.815, -0.120, p = 0.008) compared to control group. However, the effect of orange juice on body composition factors and other CVD risk factors was not significant compared to control group. These lowering effects of glucose, HOMA-IR, total cholesterol, and LDL-C were robust in subgroups with orange juice consumption ≥500 ml/day. This meta-analysis suggests that orange juice may be beneficial in improving several CVD risk factors.

Flavonoids in adipose tissue inflammation and atherosclerosis: one arrow, two targets

Flavonoids are polyphenolic compounds naturally occurring in fruits and vegetables, in addition to beverages such as tea and coffee. Flavonoids are emerging as potent therapeutic agents for cardiovascular as well as metabolic diseases. Several studies corroborated an inverse relationship between flavonoid consumption and cardiovascular disease (CVD) or adipose tissue inflammation (ATI). Flavonoids exert their anti-atherogenic effects by increasing nitric oxide (NO), reducing reactive oxygen species (ROS), and decreasing pro-inflammatory cytokines. In addition, flavonoids alleviate ATI by decreasing triglyceride and cholesterol levels, as well as by attenuating inflammatory mediators. Furthermore, flavonoids inhibit synthesis of fatty acids and promote their oxidation. In this review, we discuss the effect of the main classes of flavonoids, namely flavones, flavonols, flavanols, flavanones, anthocyanins, and isoflavones, on atherosclerosis and ATI. In addition, we dissect the underlying molecular and cellular mechanisms of action for these flavonoids. We conclude by supporting the potential benefit for flavonoids in the management or treatment of CVD; yet, we call for more robust clinical studies for safety and pharmacokinetic values.

Effects of dietary flavonoids on performance, blood constituents, carcass composition and small intestinal morphology of broilers: a meta-analysis

OBJECTIVE

This study aims to evaluate the influence of dietary flavonoids on the growth performance, blood and intestinal profiles, and carcass characteristics of broilers by employing a meta-analysis method.

METHODS

A database was built from published studies which have reported on the addition of various levels of flavonoids from herbs into broiler diets and then monitored growth performance, blood constituents, carcass proportion and small intestinal morphology. A total of 42 articles were integrated into the database. Several forms of flavonoids in herbs were applied in the form of unextracted and crude extracts. The database compiled was statistically analyzed using mixed model methodology. Different studies were considered as random effects, and the doses of flavonoids were treated as fixed effects. The model statistics used were the p-values and the Akaike information criterion. The significance of an effect was stated when its p-value was <0.05.

RESULTS

Dietary flavonoids increased (quadratic pattern; p<0.05) the average daily gain of broilers in the finisher phase. There was a reduction (p<0.01) in the feed conversion ratio of the broilers both in the starter (linear pattern) and finisher phases (quadratic pattern). The mortality rate tended to decrease linearly (p<0.1) with the addition of flavonoids, while the carcass parameter was generally not influenced. A reduction (p<0.001) in cholesterol and malondialdehyde concentrations (both linearly) was observed, while super oxide dismutase activity increased linearly (p<0.001). Increasing the dose of flavonoids increased (p<0.01) the villus height (VH) and villus height and crypt depth (VH:CD) ratio (p<0.05) in the duodenum. Similarly, the VH:CD ratio was elevated (p<0.001) in the jejunum following flavonoid supplementation.

CONCLUSION

Increasing levels of flavonoids in broilers diet leads to an improvement in growth performance, blood constituents, carcass composition and small intestinal morphology.

An insight into the health-promoting effects of taxifolin (dihydroquercetin)

Taxifolin (3,5,7,3,4-pentahydroxy flavanone or dihydroquercetin) is a flavonoid commonly found in onion, milk thistle, French maritime pine bark and Douglas fir bark. It is also used in various commercial preparations like Legalon™, Pycnogenol^®, and Venoruton^®. This review focuses on taxifolin's biological activities and related molecular mechanisms. Published literatures were gathered from the scientific databases like PubMed, SciFinder, ScienceDirect, Wiley Online Library, Google Scholar, and Web of Science up to January 2019. Taxifolin showed promising pharmacological activities in the management of inflammation, tumors, microbial infections, oxidative stress, cardiovascular, and liver disorders. The anti-cancer activity was more prominent than other activities evaluated using different in vitro and in vivo models. Further research on the pharmacokinetics, in-depth molecular mechanisms, and safety profile using well-designed randomized clinical studies are suggested to develop a drug for human use.

Nutrients, Bioactive Compounds and Bioactivity: The Health Benefits of Sweet Cherries (Prunus avium L.)

Background:

Sweet cherries are one of the most appreciated fruits worldwide as well as one of the great sources of several active substances, as phytochemical compounds (carotenoids, serotonin, melatonin and phenolic compounds) as well as in nutritive compounds (sugars and organic acids). Accumulating research demonstrate that their supplementation in our daily diet can contradict oxidative stress, mitigating or even attenuating chronic diseases, as cancerous processes, antiinflammatory- related disorders, diabetes, and neurological and cardiovascular pathologies. Therefore, the aims of this review are to present an overview on the effects of sweet cherries as health promotors, giving emphasis to the health benefits of their bioactive compounds, particularly their antimicrobial, antioxidant, antidiabetic, anticancer, anti-neurodegeneration, anti-inflammatory and cardiovascular effects.

Methods:

Research and online content about sweet cherry fruits is reviewed. The information available has been read several times to avoid inconsistencies. In addition, according what we read, original figures were done and added to facilitate understanding and to enrich the paper.

Results:

In this review, a total of 202 original reports were used. In respect to health benefits, it is possible to confirm by several studies that, in fact, the consumption of sweet cherries has positive impacts in human health, owing to their wealthy and vast constitution, particularly in phenolic compounds, vitamins and carotenoids whose health properties were already documented.

Conclusion:

The findings of this review support the evidence that sweet cherries can be applied in pharmaceutical and food formulations, since they are able to diminish free radical species and proinflammatory markers, preventing and/ or ameliorating oxidative-stress disorders.

Beneficial Effects of Citrus Flavonoids on Cardiovascular and Metabolic Health

The prevalence of cardiovascular disease (CVD) is increasing over time. CVD is a comorbidity in diabetes and contributes to premature death. Citrus flavonoids possess several biological activities and have emerged as efficient therapeutics for the treatment of CVD. Citrus flavonoids scavenge free radicals, improve glucose tolerance and insulin sensitivity, modulate lipid metabolism and adipocyte differentiation, suppress inflammation and apoptosis, and improve endothelial dysfunction. The intake of citrus flavonoids has been associated with improved cardiovascular outcomes. Although citrus flavonoids exerted multiple beneficial effects, their mechanisms of action are not completely established. In this review, we summarized recent findings and advances in understanding the mechanisms underlying the protective effects of citrus flavonoids against oxidative stress, inflammation, diabetes, dyslipidemia, endothelial dysfunction, and atherosclerosis. Further studies and clinical trials to assess the efficacy and to explore the underlying mechanism(s) of action of citrus flavonoids are recommended.

Hesperidin, a major flavonoid in orange juice, might not affect lipid profile and blood pressure: A systematic review and meta-analysis of randomized controlled clinical trials

Previous studies have led to conflicting results regarding the effect of hesperidin supplementation on cardiometabolic markers. This study aimed to evaluate the efficacy of hesperidin supplementation on lipid profile and blood pressure through a systematic review and meta-analysis of randomized controlled trials (RCTs). PubMed, Web of Science, Scopus, and Google Scholar, as well as the reference lists of the identified relevant RCTs, were searched up to May 2018. Effect sizes were pooled by using the random effects model. Ten RCTs (577 participants) were eligible to be included in the systematic review. The meta-analysis revealed that hesperidin supplementation had no effect on serum total cholesterol (weighted mean difference [WMD] = -1.04 mg/dl; 95% confidence interval [CI]: -5.65, 3.57), low-density lipoprotein cholesterol (WMD = -1.96 mg/dl; 95% CI [-7.56, 3.64]), high-density lipoprotein cholesterol (WMD = 0.16 mg/dl; 95% CI [-1.94, 2.28]), and triglyceride (WMD = 0.69 mg/dl; 95% CI [-5.91, 7.30]), with no significant between-study heterogeneity. Hesperidin supplement also had no effect on systolic (WMD = -0.85 mmHg; 95% CI [-3.07, 1.36]) and diastolic blood pressure (WMD = -0.48 mmHg; 95% CI [-2.39, 1.42]). Hesperidin supplementation might not improve lipid profile and blood pressure. Future well-designed trials are still needed to confirm these results.

Sorghum Phytochemicals and Their Potential Impact on Human Health

Sorghum contains a wide array of phytochemicals and their levels are affected by the genotype. Phytochemicals identified in sorghum include phenolic acids, flavonoids, condensed tannins, polycosanols, phytosterols, stilbenes, and phenolamides. Most of these phytochemicals are concentrated in the bran fraction and have been shown to have several potential health benefits, which include antidiabetic, cholesterol-lowering, anti-inflammatory, and anticancer properties. This chapter gives an overview of sorghum genetics relevant to phytochemicals, phytochemicals identified in sorghum grain, and their potential health benefits.

Natural products as modulators of the nuclear receptors and metabolic sensors LXR, FXR and RXR

Nuclear receptors (NRs) represent attractive targets for the treatment of metabolic syndrome-related diseases. In addition, natural products are an interesting pool of potential ligands since they have been refined under evolutionary pressure to interact with proteins or other biological targets. This review aims to briefly summarize current basic knowledge regarding the liver X (LXR) and farnesoid X receptors (FXR) that form permissive heterodimers with retinoid X receptors (RXR). Natural product-based ligands for these receptors are summarized and the potential of LXR, FXR and RXR as targets in precision medicine is discussed.

Effects of alfalfa flavonoids on broiler performance, meat quality, and gene expression

Two hundred and forty 1-d-old Arbor Acre female broilers were used to study the effects of alfalfa flavonoids (AF) on broiler performance, meat quality, and gene expression. Chicken were fed with basal diet supplemented with AF at 0, 5, 10, or 15 mg kg−1 diet for a period of 42 d. Growth performance, meat quality, antioxidant effect and lipoprotein lipase (LPL), adipose triglyceride lipase (ATGL), peroxisome proliferator-activated receptor γ (PPARγ), and fatty acid synthase (FAS) gene expressions were investigated. Results showed that AF inclusion in the diet enhanced the body weight (BW) at 42 d of age and the average daily gain from 0 to 42 d, decreased the total cholesterol (TC) and low-density lipoprotein cholesterol (LDL) levels and increased HDL level in the serum, enhanced the superoxide dismutase (SOD), catalase (CAT), total antioxidant capacity (T-AOC), and glutathione peroxidase (GSH-Px), and decreased the malondialdehyde (MDA) concentrations in the serum. Also, AF supplementation decreased the abdomen fat rate, marble, and the drip loss and storage loss after the storage for 96 h. Gene expressions’ results showed that AF inclusion decreased the FAS expression and increased the LPL, PPARγ, and ATGL expressions in the liver and adipose tissues, especially when the AF inclusion level was 15 mg kg−1 diet. These results indicate that AF were found to be effective for average daily gain and breast percentage promoting, meat quality and antioxidant activity improvement via upregulating the LPL, ATGL, PPARγ, and downregulating the FAS expression in adipose and liver tissues.

Effects of alfalfa flavonoids on broiler performance, meat quality, and gene expression

Two hundred and forty 1-d-old Arbor Acre female broilers were used to study the effects of alfalfa flavonoids (AF) on broiler performance, meat quality, and gene expression. Chicken were fed with basal diet supplemented with AF at 0, 5, 10, or 15 mg kg−1 diet for a period of 42 d. Growth performance, meat quality, antioxidant effect and lipoprotein lipase (LPL), adipose triglyceride lipase (ATGL), peroxisome proliferator-activated receptor γ (PPARγ), and fatty acid synthase (FAS) gene expressions were investigated. Results showed that AF inclusion in the diet enhanced the body weight (BW) at 42 d of age and the average daily gain from 0 to 42 d, decreased the total cholesterol (TC) and low-density lipoprotein cholesterol (LDL) levels and increased HDL level in the serum, enhanced the superoxide dismutase (SOD), catalase (CAT), total antioxidant capacity (T-AOC), and glutathione peroxidase (GSH-Px), and decreased the malondialdehyde (MDA) concentrations in the serum. Also, AF supplementation decreased the abdomen fat rate, marble, and the drip loss and storage loss after the storage for 96 h. Gene expressions’ results showed that AF inclusion decreased the FAS expression and increased the LPL, PPARγ, and ATGL expressions in the liver and adipose tissues, especially when the AF inclusion level was 15 mg kg−1 diet. These results indicate that AF were found to be effective for average daily gain and breast percentage promoting, meat quality and antioxidant activity improvement via upregulating the LPL, ATGL, PPARγ, and downregulating the FAS expression in adipose and liver tissues.

Role of hesperetin in LDL-receptor expression in hepatoma HepG2 cells

BACKGROUND

High plasma concentration of low-density lipoprotein cholesterol (LDL-c) plays a significant role in the incidence of atherosclerosis and coronary heart diseases. The aim of this study was to investigate the mechanism by which the citrus flavonoid, hesperetin, regulates the LDL receptor (LDLr) gene in the human liver using the human hepatoma cell line, HepG2.

METHODS

Luciferase reporter gene assays were performed (in the absence of lipoprotein) to measure the activity of the LDLr promoter and the promoters of the sterol regulatory element binding protein (SREBP) transcription factors that control the LDLr promoter.

RESULTS

Only SREBP-1 promoter activity was significantly increased 4 h after exposure to 200 μM hesperetin. However, after 24 h incubation with 200 μM hesperetin, the activities of all the promoter-constructs, SREBP-1a, -1c, -2 and LDLr, were significantly increased. The effects of 200 μM hesperetin on elevating LDLr mRNA levels were possibly due to regulation of LDLr gene transcription by SREBP-la and SREBP-2.

CONCLUSIONS

We conclude that 200 μM hesperetin was likely to have stimulated LDLr gene expression in human hepatoma HepG2 cells via increased phosphorylation of PI3K andERK1/2, which increased SREBP-1a and SREBP-2 mRNA levels and enhanced the maturation of the encoded proteins. This may lead to lower plasma LDL cholesterol; therefore, diets supplemented with hesperidin might provide cardio-protective effects and reduce mortality and morbidity from coronary heart diseases.

Citrus flavanones prevent systemic inflammation and ameliorate oxidative stress in C57BL/6J mice fed high-fat diet

The flavanones hesperidin, eriocitrin and eriodictyol were investigated for their prevention of the oxidative stress and systemic inflammation caused by high-fat diet in C57BL/6J mice. The mice received a standard diet (9.5% kcal from fat), high-fat diet (45% kcal from fat) or high-fat diet supplemented with hesperidin, eriocitrin or eriodictyol for a period of four weeks. Hesperidin, eriocitrin and eriodictyol increased the serum total antioxidant capacity, and restrained the elevation of interleukin-6 (IL-6), macrophage chemoattractant protein-1 (MCP-1), and C-reactive protein (hs-CRP). In addition, the liver TBARS levels and spleen mass (g per kg body weight) were lower for the flavanone-treated mice than in the unsupplemented mice. Eriocitrin and eriodictyol reduced TBARS levels in the blood serum, and hesperidin and eriodictyol also reduced fat accumulation and liver damage. The results showed that hesperidin, eriocitrin and eriodictyol had protective effects against inflammation and oxidative stress caused by high-fat diet in mice, and may therefore prevent metabolic alterations associated with the development of cardiovascular diseases in other animals.

Flavonoids as Potent Scavengers of Hydroxyl Radicals

Oxidative stress is a fundamental principle in the pathophysiology of many diseases. It occurs when the production of reactive oxygen species exceeds the capacity of the cell defense system. The hydroxyl radical is a reactive oxygen species that is commonly formed in vivo and can cause serious damage to biomolecules, such as lipids, proteins, and nucleic acids. It plays a role in inflammation-related diseases, like chronic inflammation, neurodegeneration, and cancer. To overcome excessive oxidative stress and thus to prevent or stop the progression of diseases connected to it, scientists try to combat oxidative stress and to find antioxidant molecules, including those that scavenge hydroxyl radical or diminish its production in inflamed tissues. This article reviews various methods of hydroxyl radical production and scavenging. Further, flavonoids, as natural plant antioxidants and essential component of the human diet, are reviewed as compounds interacting with the production of hydroxyl radicals. The relationship between hydroxyl radical scavenging and the structure of the flavonoids is discussed. The structural elements of the flavonoid molecule most important for hydroxyl radical scavenging are hydroxylation of ring B and a C2-C3 double bond connected with a C-3 hydroxyl group and a C-4 carbonyl group. Hydroxylation of ring A also enhances the activity, as does the presence of gallate and galactouronate moieties as substituents on the flavonoid skeleton.

Orange juice consumption and its effect on blood lipid profile and indices of the metabolic syndrome; a randomised, controlled trial in an at-risk population

Despite media concern, daily orange juice consumption did not result in adverse metabolic effects, despite providing additional dietary sugars.

Physical properties and biological activities of hesperetin and naringenin in complex with methylated β-cyclodextrin

The aim of this work is to improve physical properties and biological activities of the two flavanones hesperetin and naringenin by complexation with β-cyclodextrin (β-CD) and its methylated derivatives (2,6-di-O-methyl-β-cyclodextrin, DM-β-CD and randomly methylated-β-CD, RAMEB). The free energies of inclusion complexes between hesperetin with cyclodextrins (β-CD and DM-β-CD) were theoretically investigated by molecular dynamics simulation. The free energy values obtained suggested a more stable inclusion complex with DM-β-CD. The vdW force is the main guest–host interaction when hesperetin binds with CDs. The phase solubility diagram showed the formation of a soluble complex of A_L type, with higher increase in solubility and stability when hesperetin and naringenin were complexed with RAMEB. Solid complexes were prepared by freeze-drying, and the data from differential scanning calorimetry (DSC) confirmed the formation of inclusion complexes. The data obtained by the dissolution method showed that complexation with RAMEB resulted in a better release of both flavanones to aqueous solution. The flavanones-β-CD/DM-β-CD complexes demonstrated a similar or a slight increase in anti-inflammatory activity and cytotoxicity towards three different cancer cell lines. The overall results suggested that solubilities and bioactivities of both flavanones were increased by complexation with methylated β-CDs.

Scavenging of Toxic Acrolein by Resveratrol and Hesperetin and Identification of Adducts

The objective of this study was to investigate the ability of resveratrol and hesperetin to scavenge acrolein at pH 7.4 and 37 °C. About 6.4 or 5.2% of acrolein remained after reaction with resveratrol or hesperetin for 12 h at equimolar concentrations. An acrolein-resveratrol adduct and two acrolein-hesperetin adducts were isolated. Their structures were elucidated using mass and NMR spectroscopy. Acrolein reacted with resveratrol at the C-2 and C-3 positions through nucleophilic addition and formed an additional heterocyclic ring. Two similar monoacrolein-conjugated adducts were identified for hesperetin. Spectroscopic data suggested each acrolein-hesperetin adduct was a mixture of four stereoisomers due to the existence of two chiral carbon atoms. Yield of adducts was low at pH 5.4 but increased at pH 7.4 and 8.4. Higher pH also promoted the formation of diacrolein adducts. Results suggest that resveratrol and hesperetin exert health benefits in part through neutralizing toxic acrolein in vivo.

Effects of flavones of sea buckthorn fruits on growth performance, carcass quality, fat deposition and lipometabolism for broilers

The objective of this study was to evaluate the effects of different levels of flavones of sea buckthorn fruits (FSBF) on growth performance, carcass quality, fat deposition, and lipometabolism for broilers. 240 one-day-old Arbor Acres male broilers were randomly allotted to 4 dietary treatments (0, 0.05%, 0.10%, and 0.15% FSBF) with 6 replicates of 10 birds. Broilers were reared for 42 d. Results showed FSBF quadratically improved average daily feed intake (ADFI), average daily gain (ADG), and final body weight (BW) (P = 0.002, P = 0.019 and P = 0.018, respectively). The abdominal fat percentage in 0.05%, 0.10%, and 0.15% FSBF supplementation groups was decreased by 21.08%, 19.12%, and 19.61% with respect to the control group, respectively (P < 0.05). The intramuscular fat (IMF) content in the breast muscle of the broilers was increased by 7.21%, 23.42% and 6.30% in 0.05%, 0.10% and 0.15% FSBF groups, and that in the thigh meat was raised by 4.43%, 24.63% and 12.32%, compared with the control group, respectively (P < 0.05). FSBF had a quadratic effect on the abdominal fat percentage and IMF in the breast muscle (P < 0.05). Dietary FSBF also modified fatty acids of muscular tissues, resulting in a higher ratio of unsaturated to saturated fatty acids (P < 0.05). Supplementing FSBF in the diet greatly decreased the levels of triglyceride, cholesterol, and low-density lipoprotein cholesterol (P < 0.05). Moreover, the quadratic responses were also observed in the levels of insulin and adiponectin in serum (P = 0.020 and P = 0.037, respectively). Abdominal fat percentage was correlated negatively with insulin and positively with adiponectin (P < 0.05). IMF content in the breast and thigh muscles were correlated positively with insulin, and negatively with adiponectin (P < 0.05). A positive correlation existed between breast muscle, IMF, and leptin (P < 0.05). In conclusion, adding FSBF into the diets affected growth performance and fat deposition of broilers by regulating lipometabolism. Fat deposition and distribution of broilers were closely associated with concentrations of insulin and adiponectin. The optimal level of FSBF supplemented in diet was 0.05 to 0.10% in this study.

Naringenin prevents obesity, hepatic steatosis, and glucose intolerance in male mice independent of fibroblast growth factor 21

The molecular mechanisms and metabolic pathways whereby the citrus flavonoid, naringenin, reduces dyslipidemia and improves glucose tolerance were investigated in C57BL6/J wild-type mice and fibroblast growth factor 21 (FGF21) null (Fgf21(-/-)) mice. FGF21 regulates energy homeostasis and the metabolic adaptation to fasting. One avenue of this regulation is through induction of peroxisome proliferator-activated receptor-γ coactivator-1α (Pgc1a), a regulator of hepatic fatty acid oxidation and ketogenesis. Because naringenin is a potent activator of hepatic FA oxidation, we hypothesized that induction of FGF21 might be an integral part of naringenin's mechanism of action. Furthermore, we predicted that FGF21 deficiency would potentiate high-fat diet (HFD)-induced metabolic dysregulation and compromise metabolic protection by naringenin. The absence of FGF21 exacerbated the response to a HFD. Interestingly, naringenin supplementation to the HFD robustly prevented obesity in both genotypes. Gene expression analysis suggested that naringenin was not primarily targeting fatty acid metabolism in white adipose tissue. Naringenin corrected hepatic triglyceride concentrations and normalized hepatic expression of Pgc1a, Cpt1a, and Srebf1c in both wild-type and Fgf21(-/-) mice. HFD-fed Fgf21(-/-) mice displayed greater muscle triglyceride deposition, hyperinsulinemia, and impaired glucose tolerance as compared with wild-type mice, confirming the role of FGF21 in insulin sensitivity; however, naringenin supplementation improved these metabolic parameters in both genotypes. We conclude that FGF21 deficiency exacerbates HFD-induced obesity, hepatic steatosis, and insulin resistance. Furthermore, FGF21 is not required for naringenin to protect mice from HFD-induced metabolic dysregulation. Collectively these studies support the concept that naringenin has potent lipid-lowering effects and may act as an insulin sensitizer in vivo.

Consumption of orange fermented beverage reduces cardiovascular risk factors in healthy mice

The consumption of fruits prevents the risk of cardiovascular diseases. Alcoholic fermentation has been carried out in fruits resulting in products which provide high concentration of bioactive compounds and variable alcohol content. The aim of this study was to assess the potential beneficial effect of an orange beverage obtained by alcoholic fermentation and pasteurization of orange juice on cardiovascular risk biomarkers. For this purpose, four mice groups (n = 8) ingested orange beverage (equivalent volume to 250 mL/day in human), orange juice, alcoholic solution (at the proportional amount of orange beverage) or water during 12 weeks. The equivalent amount to double serving of orange beverage (500 mL/day) was administered to mice in a subsequent intervention, and a control group was also evaluated. Orange beverage consumption increased levels of glutathione and uric acid, improved lipid profile, decreased oxidized LDL and maintained levels of IL-6 and C-reactive protein. Synergistic effects between the bioactive compounds and the alcohol content of orange beverage may occur. The intake of double serving also increased antioxidant enzyme activities, bilirubin content and plasma antioxidant capacity. These results suggest that orange beverage may produce greater protection against cardiovascular risk factors than orange juice in healthy mice.

Molecular mechanisms behind the biological effects of hesperidin and hesperetin for the prevention of cancer and cardiovascular diseases

Hesperidin (Hsd) and its aglycone, hesperetin (Hst), are two flavonoids from citrus species that have various biological properties, particularly those for the prevention of cancer and cardiovascular diseases. Studies have shown both anti-cancer and cancer chemopreventive effects for Hsd and Hst. Cancer chemopreventive properties of Hsd and Hst are mainly associated with their antioxidant, radical scavenging and anti-inflammatory activities. In addition, Hsd and Hst interfere at different stages of cancer. Unlike conventional anti-cancer drugs, Hsd and Hst inhibit tumor growth by targeting multiple cellular protein targets at the same time, including caspases, Bcl-2 (B-cell lymphoma 2) and Bax (Bcl-2 associated X protein) for the induction of apoptosis, and COX-2 (cyclooxygenase-2), MMP-2 (matrix metalloproteinase-2) and MMP-9 for the inhibition of angiogenesis and metastasis. The results of the recent basic and clinical studies revealed the beneficial effects for Hst, Hsd and their derivatives in the treatment of heart failure and cardiac remodeling, myocardial ischemia and infarction, and hypertension. In addition, the valuable effects of Hst and Hsd in the treatment of diabetes and dyslipidemia with their anti-platelet and anticoagulant effects make them good candidates in the treatment of various cardiovascular diseases. In this review, new findings regarding the molecular targets of Hsd and Hst, animal studies and clinical trials are discussed.

Comparison of flavonoid compounds in the flavedo and juice of two pummelo cultivars (Citrus grandis L. Osbeck) from different cultivation regions in China

The objective of this study was to investigate the effect of different cultivation regions on the pattern and content of flavonoids in two pummelo cultivars (C. grandis L. Osbeck) in China. Results showed that similar patterns of flavonoids were observed in the flavedo or juice of each pummelo cultivar from these cultivation regions, whereas the individual flavonoid content showed unique characteristics. Naringin, the predominant flavanone glycoside, showed the highest content in both flavedo and juice of C. grandis "Guanximiyu" from the Pinghe of Fujian (FJ) cultivation region compared with the Dapu of Guangdong (GD) and Nanbu of Sichuan (SC) regions. However, its content in the flavedo of C. grandis "Shatianyu" from the Pingle of Guangxi (GX) was significantly lower than in the GD and SC regions. Vicenin-2 appeared to be the dominant flavone C-glycoside in the flavedo of both cultivars, and the lowest content was observed in the flavedo of C. grandis "Guanximiyu" from the SC region. However, C. grandis "Shatianyu" contained the highest content of vicenin-2 in the flavedo from SC region. Similarly, the predominant flavone O-glucoside, rhoifolin, showed the highest content in C. grandis "Guanximiyu" from the GD and FJ regions, whereas C. grandis "Shatianyu" in SC region showed the highest content of rhoifolin. Cluster analysis suggested that genotype played a primary role in determining the flavonoid profiles of pummelo cultivars, whereas regional differences significantly affected the flavonoid distribution of pummelo cultivars potentially via affecting the direction of flavonoid accumulation in pummelo.

Antiartherosclerotic effects of plant flavonoids

Atherosclerosis is the process of hardening and narrowing the arteries. Atherosclerosis is generally associated with cardiovascular diseases such as strokes, heart attacks, and peripheral vascular diseases. Since the usage of the synthetic drug, statins, leads to various side effects, the plants flavonoids with antiartherosclerotic activity gained much attention and were proven to reduce the risk of atherosclerosis in vitro and in vivo based on different animal models. The flavonoids compounds also exhibit lipid lowering effects and anti-inflammatory and antiatherogenic properties. The future development of flavonoids-based drugs is believed to provide significant effects on atherosclerosis and its related diseases. This paper discusses the antiatherosclerotic effects of selected plant flavonoids such as quercetin, kaempferol, myricetin, rutin, naringenin, catechin, fisetin, and gossypetin.

Molecular mechanism underlying hesperetin-induced apoptosis by in silico analysis and in prostate cancer PC-3 cells

AIM

To investigate the molecular mechanisms underlying triggering of apoptosis by hesperetin using in silico and in vitro methods.

METHODS

The mechanism of binding of hesperetin with NF-?B and other apoptotic proteins like BAX, BAD, BCL2 and BCLXL was analysed in silico using Schrodinger suite 2009. In vitro studies were also carried out to evaluate the potency of hesperetin in inducing apoptosis using the human prostate cancer PC-3 cell line.

RESULTS

Hesperetin was found to exhibit high-affinity binding resulting from greater intermolecular forces between the ligand and its receptor NF-?B (-7.48 Glide score). In vitro analysis using MTT assay confirmed that hesperetin reduced cell proliferation (IC50 values of 90 and 40μM at 24 and 48h respectively) in PC-3 cells. Hesperetin also downregulated expression of the anti-apoptotic gene BCLXL at both mRNA and protein levels and increased the expression of pro-apoptotic genes like BAD at mRNA level and BAX at mRNA as well as protein levels.

CONCLUSION

The results suggest that hesperetin can induce apoptosis by inhibiting NF-?B.

Mechanisms for food polyphenols to ameliorate insulin resistance and endothelial dysfunction: therapeutic implications for diabetes and its cardiovascular complications

The rising epidemic of diabetes is a pressing issue in clinical medicine worldwide from both healthcare and economic perspectives. This is fueled by overwhelming increases in the incidence and prevalence of obesity. Obesity and diabetes are characterized by both insulin resistance and endothelial dysfunction that lead to substantial increases in cardiovascular morbidity and mortality. Reciprocal relationships between insulin resistance and endothelial dysfunction tightly link metabolic diseases including obesity and diabetes with their cardiovascular complications. Therefore, therapeutic approaches that target either insulin resistance or endothelial dysfunction alone are likely to simultaneously improve both metabolic and cardiovascular pathophysiology and disease outcomes. Moreover, combination therapies with agents targeting distinct mechanisms are likely to have additive or synergistic benefits. Conventional therapies for diabetes and its cardiovascular complications that are both safe and effective are insufficient to meet rising demand. Large, robust, epidemiologic studies demonstrate beneficial metabolic and cardiovascular health effects for many functional foods containing various polyphenols. However, precise molecular mechanisms of action for food polyphenols are largely unknown. Moreover, translation of these insights into effective clinical therapies has not been fully realized. Nevertheless, some functional foods are likely sources for safe and effective therapies and preventative strategies for metabolic diseases and their cardiovascular complications. In this review, we emphasize recent progress in elucidating molecular, cellular, and physiological actions of polyphenols from green tea (EGCG), cocoa (ECG), and citrus fruits (hesperedin) that are related to improving metabolic and cardiovascular pathophysiology. We also discuss a rigorous comprehensive approach to studying functional foods that is essential for developing novel, effective, and safe medications derived from functional foods that will complement existing conventional drugs.

Bergamot polyphenolic fraction enhances rosuvastatin-induced effect on LDL-cholesterol, LOX-1 expression and protein kinase B phosphorylation in patients with hyperlipidemia

BACKGROUND

Statins are the most commonly prescribed drugs to reduce cardiometabolic risk. Besides the well-known efficacy of such compounds in both preventing and treating cardiometabolic disorders, some patients experience statin-induced side effects. We hypothesize that the use of natural bergamot-derived polyphenols may allow patients undergoing statin treatment to reduce effective doses while achieving target lipid values. The aim of the present study is to investigate the occurrence of an enhanced effect of bergamot-derived polyphenolic fraction (BPF) on rosuvastatin-induced hypolipidemic and vasoprotective response in patients with mixed hyperlipidemia.

METHODS

A prospective, open-label, parallel group, placebo-controlled study on 77 patients with elevated serum LDL-C and triglycerides was designed. Patients were randomly assigned to a control group receiving placebo (n=15), two groups receiving orally administered rosuvastatin (10 and 20mg/daily for 30 days; n=16 for each group), a group receiving BPF alone orally (1000 mg/daily for 30 days; n=15) and a group receiving BPF (1000 mg/daily given orally) plus rosuvastatin (10mg/daily for 30 days; n=15).

RESULTS

Both doses of rosuvastatin and BPF reduced total cholesterol, LDL-C, the LDL-C/HDL-C ratio and urinary mevalonate in hyperlipidemic patients, compared to control group. The cholesterol lowering effect was accompanied by reductions of malondialdehyde, oxyLDL receptor LOX-1 and phosphoPKB, which are all biomarkers of oxidative vascular damage, in peripheral polymorphonuclear cells.

CONCLUSIONS

Addition of BPF to rosuvastatin significantly enhanced rosuvastatin-induced effect on serum lipemic profile compared to rosuvastatin alone. This lipid-lowering effect was associated with significant reductions of biomarkers used for detecting oxidative vascular damage, suggesting a multi-action enhanced potential for BPF in patients on statin therapy.

Hesperetin Stimulates Cholecystokinin Secretion in Enteroendocrine STC-1 Cells

Hesperetin (3',5,7-trihydroxy 4'-methoxyflavanone) and its glycoside hesperidin (hesperetin 7-rhamnoglucoside) in oranges have been reported to possess pharmacological effects related to anti-obesity. However, hesperetin and hesperidin have not been studied on suppressive effects on appetite. This study examined that hesperetin and hesperidin can stimulate the release of cholecystokinin (CCK), one of appetite-regulating hormones, from the enteroendocrine STC-1 cells, and then examined the mechanisms involved in the CCK release. Hesperetin significantly and dose-dependently stimulated CCK secretion with an EC₅₀ of 0.050 mM and increased the intracellular Ca²⁺ concentrations ([Ca²⁺]_i) compared to the untreated control. The stimulatory effect by hesperetin was mediated via the entry of extracellular Ca²⁺ and the activation of TRP channels including TRPA1. These results suggest that hesperetin can be a candidate biomolecule for the suppression of appetite and eventually for the therapeutics of obesity.

Long-term orange juice consumption is associated with low LDL-cholesterol and apolipoprotein B in normal and moderately hypercholesterolemic subjects

BACKGROUND

This study investigated the hypothesis that long-term orange juice consumption (≥ 12 months) was associated with low risk factors for cardiovascular disease in adult men and women with normal and moderately high cholesterol blood levels.

METHODS

The sample consisted of 103 men (18-66 y) and 26 women (18-65 y); all were employees of an orange juice factory with daily access to free orange juice. The results showed that 41% of the individuals consumed 2 cups (480 mL) of orange juice per day for at least twelve months, while 59% of the volunteers are non-consumers of orange juice.

RESULTS

Orange juice consumers with normal serum lipid levels had significantly lower total cholesterol (-11%, p <0.001), LDL-cholesterol (-18%, p < 0.001), apolipoprotein B (apo B) (-12%, p < 0.01) and LDL/HDL ratio (-12%, p < 0.04) in comparison to non-consumers, as did the consumers with moderate hypercholesterolemia: lower total cholesterol (-5%, p <0.02), LDL-cholesterol (-12%, p <0.03), apolipoprotein B (-12%, p <0.01) and LDL/HDL ratio (-16%, p <0.05) in comparison the non-consumers counterparts. Serum levels of homocysteine, HDL- cholesterol and apolipoprotein A-1, body composition and the dietary intake of food energy and macronutrients did not differ among orange juice consumers and non-consumers, but vitamin C and folate intake was higher in orange juice consumers.

CONCLUSION

Long-term orange juice consumers had lower levels of total cholesterol, LDL-cholesterol, apo B and LDL/HDL ratio and an improvement of folate and vitamin C in their diet.

Effect of increasing levels of bioflavonoids in broiler feed on plasma anti-oxidative potential, lipid metabolites, and fatty acid composition of meat

This study was conducted to investigate the supplemental effects of purified bioflavonoids (genistein and hesperidin), as potential alternatives to plant/herbs or synthetic antioxidants, individually and in combination for fatty acid profile, lipid metabolites, and antioxidant status of broilers. Three hundred sixty 1-d-old broilers were divided into 6 treatment groups: control (basal diet), G5 (5 mg of genistein per kg of feed), and H20 (20 mg hesperidin per kg of feed), whereas the other 3 groups were supplemented with a mixture of genistein and hesperidin (20% genistein + 80% hesperidin) having a dosage of 5 mg•kg(-1) (GH5), 10 mg•kg(-1) (GH10), and 20 mg•kg(-1) (GH20), respectively. Broilers were slaughtered at 42 d, and breast muscle, liver, and blood samples were collected. A dose-dependent increase (P < 0.05) was observed for plasma antioxidant parameters, including total antioxidant capacity, malondialdehyde production, and total superoxide dismutase activity. Cholesterol and triglyceride contents were found to decrease (P < 0.05) in serum and breast muscle. The proportion of total polyunsaturated fatty acids and the ratio of n-6 to n-3 fatty acids and polyunsaturated fatty acids to saturated fatty acids in breast muscles was significantly improved (P < 0.05) by increasing levels of dietary bioflavonoids. The current results implied that dietary bioflavonoids genistein and hesperidin could positively improve the fatty acid and lipid metabolite profile of broiler breast meat in a dose-dependent fashion. Thus, bioflavonoids could be a feasible alternative of antioxidant plants/herbs and synthetic feed additives for the production of healthier chicken meat.

100% orange juice consumption is associated with better diet quality, improved nutrient adequacy, decreased risk for obesity, and improved biomarkers of health in adults: National Health and Nutrition Examination Survey, 2003-2006

BACKGROUND

Consumption of 100% orange juice (OJ) has been positively associated with nutrient adequacy and diet quality, with no increased risk of overweight/obesity in children; however, no one has examined these factors in adults. The purpose of this study was to examine the association of 100% OJ consumption with nutrient adequacy, diet quality, and risk factors for metabolic syndrome (MetS) in a nationally representative sample of adults.

METHODS

Data from adults 19+ years of age (n = 8,861) participating in the National Health and Nutrition Examination Survey 2003-2006 were used. The National Cancer Institute method was used to estimate the usual intake (UI) of 100% OJ consumption, selected nutrients, and food groups. Percentages of the population below the Estimated Average Requirement (EAR) or above the Adequate Intake (AI) were determined. Diet quality was measured by the Healthy Eating Index-2005 (HEI-2005). Covariate adjusted logistic regression was used to determine if consumers had a lower odds ratio of being overweight or obese or having risk factors of MetS or MetS.

RESULTS

Usual per capita intake of 100% OJ was 50.3 ml/d. Among consumers (n = 2,310; 23.8%), UI was 210.0 ml/d. Compared to non-consumers, consumers had a higher (p < 0.05) percentage (% ± SE) of the population meeting the EAR for vitamin A (39.7 ± 2.5 vs 54.0 ± 1.2), vitamin C (0.0 ± 0.0 vs 59.0 ± 1.4), folate (5.8 ± 0.7 vs 15.1 ± 0.9), and magnesium (51.6 ± 1.6 vs 63.7 ± 1.2). Consumers were also more likely to be above the AI for potassium (4.1 ± 0.8 vs 1.8 ± 0.2). HEI-2005 was significantly (p < 0.05) higher in consumers (55.0 ± 0.4 vs 49.7 ± 0.3). Consumers also had higher intakes of total fruit, fruit juice, whole fruit, and whole grain. Consumers had a lower (p < 0.05) mean body mass index (27.6 ± 0.2 vs 28.5 ± 0.1), total cholesterol levels (197.6 ± 1.2 vs 200.8 ± 0.75 mg/dL), and low density lipoprotein-cholesterol levels (112.5 ± 1.4 vs 116.7 ± 0.93 mg/dL). Finally, compared to non-consumers of 100% OJ, consumers were 21% less likely to be obese and male consumers were 36% less likely to have MetS.

CONCLUSION

The results suggest that moderate consumption of 100% OJ should be encouraged to help individuals meet the USDA daily recommendation for fruit intake and as a component of a healthy diet.

Citrus flavanones: what is their role in cardiovascular protection?

Flavanones, including hesperidin and naringin, are polyphenolic compounds highly and almost exclusively present in citrus. Epidemiological studies reported an inverse relationship between their intake and the risk of cardiovascular diseases. Clinical and experimental data further showed their antihypertensive, lipid-lowering, insulin-sensitizing, antioxidative, and anti-inflammatory properties, which could explain their antiatherogenic action in animal models. Although flavanones may be promising compounds that are particularly active in cardiovascular disease prevention, clinical data are still scarce and most in vitro data have been obtained under nonphysiologically relevant conditions. Moreover, the mechanisms responsible for flavanone action are not fully elucidated. Therefore, further research is needed to better evaluate and understand the protective effects of flavanones in cardiovascular diseases.