Total Flavanones Research Articles

Effect of Dietary Flavonoids on Circadian Syndrome: A Population-Based Cross-Sectional Study.

Background: Altering the dietary patterns can potentially decrease the likelihood of metabolic syndrome and circadian syndrome (CircS), but it remains unclear which types of flavonoid compounds are responsible for these effects, particularly among nationally representative populations. Thus, we conducted a cross-sectional study to investigate the impact of flavonoid intake on CircS. Methods: The study included 9212 noninstitutionalized adults from two survey cycles (2007-2008 and 2009-2010) of the National Health and Nutrition Examination Survey (NHANES). Data on six dietary flavonoids were collected through a 24-hr dietary recall, including isoflavones, anthocyanidins, flavan-3-ols, flavanones, flavones, and flavonols. All statistical analyses were weighted to account for the complex survey sampling design to generate nationally representative estimates. Multivariable logistic regression and propensity score matching (PSM) were performed to control for potential confounders and assess the association between the six flavonoids and risk of short sleep. Results: After adjusting for all covariates, only individuals with high intake of total flavanones exhibited a 28% [odds ratio (OR) = 0.72, 95% confidence interval (CI) = 0.64-0.83, P < 0.001] decrease in the risk of CircS. The results obtained through PSM were consistent with this finding (OR = 0.70, 95% CI = 0.61-0.80, P < 0.001). Total flavanone intake displayed a linear dose-response relationship with the likelihood of CircS (P for interaction = 0.448). Conclusions: Our findings suggest that high dietary intakes of flavanones have beneficial effects on reducing the risk of CircS.

Efficiency of Microwave and Ultrasound-Assisted Extraction as a Green Tool for Polyphenolic Isolation from Monofloral Honeys

Monofloral honey is obtained from the nectar of single-source plants and has a higher market value due to its polyphenol content associated with its biological properties, especially its antioxidant capacity. In this work, advanced extraction techniques using microwave- (MAE) and ultrasound-assisted (UAE) extraction of phenolic compounds in monofloral honey were optimized and compared. Optimal parameters for MAE were an irradiation time of 15 min, a temperature of 60 °C, and a microwave power of 300 W, and for UAE, a sonication time of 10 min, a temperature of 35 °C, and an ultrasound amplitude of 60%. The extraction solvent used was 70% ethanol. In the extracts of different monofloral honey samples (mint, fennel, raspberry, lavender, sage, buckwheat, maroon, heaven) obtained at optimal MAE and UAE conditions, polyphenolic compounds were determined using UPLC-ESI/MS2 analysis and antioxidant capacity using ORAC, ABTS, and DPPH assays. The results showed that UAE was the more efficient technique for the extraction of total flavanones, flavones, hydroxycinnamic acids, and total phenols, and MAE for total flavonols and hydroxybenzoic acids. The antioxidant ORAC and DPPH capacity was higher for the extracts obtained with MAE, while the ABTS capacity was higher for those obtained with UAE.

Optimization of Extraction Conditions using Response Surface Methodology and HPTLC Fingerprinting Analysis of Indian Propolis

The potential of Indian propolis as a suitable therapeutic agent is still to be explored to the fullest. As variation in the chemical composition across different geographical regions has been a major concern, it is, therefore, worthwhile to systematically investigate, and assess the quality of Indian propolis and set nationalized standards. The propolis collected from three different regions were authenticated for the major plant source, followed by the evaluation of physicochemical properties. Different extraction methods were compared, with their influence on balsam content, polyphenol, and flavonoid content. The sample coded HAR using ultrasonication gave the highest extraction yield of 71.87%. Further, the process variables in the ultrasonication method (i.e. Amplitude, extraction time, the concentration of ethanol) at three levels were optimized using the Box-Behnken response design. The model was found significant with the concentration of ethanol having a maximum influence on the responses. The model was successfully verified by setting the amplitude at 48%, extraction time to 5.6 mins, and ethanol concentration to 87% v/v. The extraction efficiency of 83.86±1.17% was achieved with a substantial diminution of extraction time. The total phenolic, total flavonol, and total flavanone content of the optimized batch were 28.74±0.13 mgGAE/g, 4.66±0.78 mgQE/g, and 3.16±0.14 mgPE/g of propolis respectively. Further HPTLC fingerprint image of the optimized extract revealed the presence of quercetin, p-coumaric acid, kaempferol, chrysin, pinocembrin, and galangin.

Changes in Polyphenolic Compounds of Hutai No. 8 Grapes during Low-Temperature Storage and Their Shelf-Life Prediction by Identifying Biomarkers.

The aim of this experiment was to assess the effect of different storage temperatures on the texture quality, phenolic profile, and antioxidant capacity of a grape. Fresh grapes were stored at 4 and 25 °C for nine days and sampled on alternate days. The hardness, total phenolics, total flavanones, total flavanols, total anthocyanin content, antioxidant activity, differential metabolite screening, and key gene expression were evaluated. In addition, four phenolic compounds were screened out as differential metabolites in response to storage temperature by OPLS-DA analysis. The results showed that the fruit firmness was better maintained in low-temperature storage and the storage life was longer than that at 25 °C. During the whole storage process, the contents of phenolics, flavanones, flavanols, and anthocyanins all showed an increasing trend first and then decreased regardless of what temperature. Since the antioxidant capacity of a grape was positively correlated with the contents of total phenols and total flavonoids, the same trend was also shown. However, the grape's phenolic compound content and antioxidant activity were higher at 25 °C than at 4 °C. Furthermore, through qualitative and quantitative analysis of 16 monomeric phenols, this study selected catechin, 1-O-vanilloyl-β-d-glucose, p-coumaric acid 4-glucoside, and resveratrol-3-O-glucoside as the main differentially expressed metabolites at the two temperatures. In conclusion, for a short shelf life or immediate consumption, keeping grapes at room temperature is more beneficial to obtain high antioxidants. However, if the goal is to prolong the storage period of the fruit, keeping the fruit at 4 °C is recommended.

Illustration of the variation in the content of flavanone rutinosides in various citrus germplasms from genetic and enzymatic perspectives.

In citrus, 1,6-rhamnosytransferase (1,6RhaT) and 1,2-rhamnosytransferase (1,2RhaT) catalyze flavanone-7-O-glucosides to form nonbitter flavanone rutinosides (FRs) and bitter flavanone neohesperidosides (FNs), respectively. As revealed in this study of fruit peels from 36 citrus accessions, FRs varied from undetectable levels in pummelo and kumquat to being the dominant flavonoids in sweet orange and loose-skin mandarins. Furthermore, a previously annotated full-length 1,6RhaT-like gene was identified as another 1,6RhaT-encoding gene by in vitro experiments. In total, 28 alleles of full-length 1,6RhaTs were isolated and classified into A, B and C types with only type A alleles encoding a functional protein. Coincidently, only the accessions that contained FRs harbored type A alleles, as was further verified in two F1 hybrid populations. Moreover, the inferior substrate conversion efficiency of 1,6RhaTs in comparison with that of 1,2RhaT in vitro might partly explain the lower proportions of FRs to total flavanone disaccharides in citrus hybrids harboring both functional rhamnosyltransferases. Our findings provide a better understanding of FR content variations among citrus and are meaningful for a mechanistic illustration of citrus flavonoid metabolism and fruit quality improvement practices.

Diversion of metabolic flux towards 5-deoxy(iso)flavonoid production via enzyme self-assembly in Escherichia coli

5-Deoxy(iso)flavonoids are structural representatives of phenylpropanoid-derived compounds and play critical roles in plant ecophysiology. Recently, 5-deoxy(iso)flavonoids gained significant interest due to their potential applications as pharmaceuticals, nutraceuticals, and food additives. Given the difficulties in their isolation from native plant sources, engineered biosynthesis of 5-deoxy(iso)flavonoids in a microbial host is a highly promising alternative approach. However, the production of 5-deoxy(iso)flavonoids is hindered by metabolic flux imbalances that result in a product profile predominated by non-reduced analogues. In this study, GmCHS7 (chalcone synthase from Glycine max) and GuCHR (chalcone reductase from Glycyrrhizza uralensis) were preliminarily utilized to improve the CHR ratio (CHR product to total CHS product). The use of this enzyme combination improved the final CHR ratio from 39.7% to 50.3%. For further optimization, a protein-protein interaction strategy was employed, basing on the spatial adhesion of GmCHS7:PDZ and GuCHR:PDZlig. This strategy further increased the ratio towards the CHR-derived product (54.7%), suggesting partial success of redirecting metabolic flux towards the reduced branch. To further increase the total carbon metabolic flux, 15 protein scaffolds were programmed with stoichiometric arrangement of the three sequential catalysts GmCHS7, GuCHR and MsCHI (chalcone isomerase from Medicago sativa), resulting in a 1.4-fold increase in total flavanone production, from 69.4 mg/L to 97.0 mg/L in shake flasks. The protein self-assembly strategy also improved the production and direction of the lineage-specific compounds 7,4′-dihydroxyflavone and daidzein in Escherichia coli. This study presents a significant advancement of 5-deoxy(iso)flavonoid production and provides the foundation for production of value-added 5-deoxy(iso)flavonoids in microbial hosts.

Bioactive Compounds from Lemon (Citrus limon) Extract Overcome TNF-α-Induced Insulin Resistance in Cultured Adipocytes.

The consumption of plant-based food is important for health promotion, especially regarding the prevention and management of chronic diseases such as diabetes. We investigated the effects of a lemon extract (LE), containing ≥20.0% total flavanones and ≥1.0% total hydroxycinnamic acids, on insulin signaling in murine 3T3-L1 adipocytes treated with TNF-α, which was used to mimic in vitro the insulin resistance condition that characterizes diabetes mellitus. Our results showed LE increased PPARγ, GLUT4 and DGAT-1 levels, demonstrating the potential of this lemon extract in the management of insulin resistance conditions associated with TNF-α pathway activation. LE treatment further decreased the release of interleukin 6 (IL-6) and restored triglyceride synthesis, which is the main feature of a healthy adipocyte.

Metabolism and antioxidation regulation of total flavanones from Sedum sarmentosum Bunge against high-fat diet-induced fatty liver disease in Nile tilapia (Oreochromis niloticus).

Diet-induced fatty liver is a considerable threaten to fish aquaculture due to the popularity of the high-fat diet (HFD) feeding. Our study aims to investigate the effects of flavanones from Sedum sarmentosum Bunge (FSSB) on the liver function to identify a potential treatment for HFD-induced fatty liver disease. Physiological and pathological indicators were tested in the liver of Nile tilapia (Oreochromis niloticus) and results showed parameters including lipid metabolites, redox parameters, and inflammatory factors could be adequately restored to normal level by addition of 150 mg/kg FSSB to HFD. Proteomics analysis was performed in liver tissues from tilapia with normal diet (ND), HFD, and HFD+FSSB. Totally, 51 upregulated proteins and 77 downregulated proteins were identified in HFD groups and 67 proteins of them were restored after treated with FSSB. Bioinformatics analysis showed that differentially expressed proteins (DEPs) in HFD+FSSB150 group compared with HFD group are mainly enriched in acety-CoA metabolic process, adenosine-triphosphate (ATP) biosynthetic process, lipid metabolic process, and phospholipid metabolic process. The dysregulated proteins were involved in peroxidosome proliferators-activated receptor (PPAR) signaling pathway, fat digestion and absorption, and immune system. The quantitative real-time PCR (qRT-PCR) assay further revealed that the expression of GST, PPARα, PPARγ, and multiple-inflammatory cytokines could be also reversed in HFD group under the treatment of 150 mg/kg FSSB. Our findings demonstrated FSSB is efficient for the treatment of fatty liver disease through regulation of lipid metabolism and antioxidation in Nile tilapia, providing a new treatment of non-alcoholic fatty liver disease (NAFLD) in fish aquaculture.

Evaluation of microbiological safety, physicochemical and aromatic qualities of shiikuwasha (Citrus depressa Hayata) juice after high pressure processing.

This study evaluated high pressure processing (HPP) for achieving greater than 5-log reduction of Escherichia coli O157:H7 in shiikuwasha (Citrus depressa Hayata) juices and compare quality parameters, including microbiological safety, total phenolic content (TPC), total flavanones (TFC), and polymethoxylated flavones, browning, volatile aromatic, and physicochemical properties of HPP-treated juice with those of high-temperature short-time pasteurized juice. A HPP of 600MPa for 150s was identified capable of achieving greater than 5.15-log reductions of E. coli O157:H7 in shiikuwasha juice. The microbiological shelf life of the juices were at least 28days when processed at HPP for 600MPa/150s or HTST for 90°C/60s. The color, aromatic, and antioxidant contents (TPC, TFC, Tangeletin, Nobiletin) were well preserved after HPP, however, HTST resulted in a significant (p < 0.05) loss of antioxidant content (TPC (8.8%), Tangeletin (6.8%)), and negatively impacted the juice color. By the end of storage, the amount of these aroma relevant volatiles appears to still be higher in HPP pasteurized juices compared to their conventional counterparts. This study demonstrated that under optimal conditions of HPP can attain the same level of microbiological safety as thermal pasteurization and preserved the acceptable quality of shiikuwasha juice.

Obtaining antioxidant extracts from tangerine (C. reticulata var. Arrayana) peels by modified supercritical CO2 and their use as protective agent against the lipid oxidation of a mayonnaise

By supercritical fluid extraction (SFE) it was possible to obtain an antioxidant extract from tangerine peels (TPs) which was then tested on a mayonnaise. The TPs were submitted to SFE using CO2-EtOH as solvent. A central composite design was set up to evaluate the effect of temperature, pressure and %EtOH on the yield, the total phenolic content (TPC), the total flavanone content (TFC) and the in vitro antioxidant capacity (AC) by DPPH method. SFE extracts showed high TPC, TFC and AC. These extracts were analyzed by UHPLC-DAD, tentatively identifying eight flavonoids. The most active extract was obtained at 22.0 MPa, 80 °C, 5.0 %EtOH. This extract was tested as a mayonnaise´s antioxidant, monitoring produced TBARS (Thiobarbituric Acid Reactive Substances). It was shown to protect the mayonnaise against lipid oxidation and was as effective as the synthetic antioxidant BHA. These results profile the TPs as an applicable biomass in the food industry.

Anti-fibrotic mechanism of Sedum sarmentosum total flavanones in inhibiting activation of HSC by regulating Smads

This paper was aimed to observe the interventional effect of Sedum sarmentosum total flavanones on hepatic fibrosis and its possible mechanism through the subcutaneous injection of CCl_4 in rats. Sixty male SD rats were randomly divided into normal control group, model group, low-dose, medium-dose, high-dose S. sarmentosum total flavanones groups(100, 200, 400 mg·kg~(-1)) and silymarin group(200 mg·kg~(-1)). The model of liver fibrosis was established by subcutaneous injection of rats with 40% CCl_4. After the modeling, the drug groups were intragastrically administered with corresponding drugs once a day for consecutively five weeks, while the normal group and the model group were given 0.9% sodium chloride solution during the same period. After the experiment, the general conditions of rats and the pathological changes of liver tissues were observed, and the contents of serum ALT, AST, HA and LN were measured. Besides, the expressions of the protein and relevant mRNA of Smad2/3, Smad4 and α-SMA in rats were detected. Compared with model group, S. sarmentosum total flavanones could significantly increase the rats' body weight, inhibit the increase of liver and spleen index in rats of liver fibrosis, reduce the levels of ALT, AST, HA and LN, and alleviate pathological changes. Meanwhile, compared with the model group, the protein expressions of Smad2/3, Smad4 and α-SMA as well as relevant mRNA expressions in S. sarmentosum total flavanones group were obviously decreased, while Smad7 expression was markedly increased. As a result, S. sarmentosum total flavanones could significantly alleviate CCl_4-induced liver fibrosis, and its anti-hepatic fibrosis mechanism may be related to intervention with Smads pathway, so as to inhibit the activation of HSC.

Dietary flavonoids and the prevalence and 15-y incidence of age-related macular degeneration

The majority of research performed to date has examined the effects of commonly known antioxidants such as vitamins C, E, and A and carotenoids on age-related macular degeneration (AMD) risk and progression. To date, there is limited research on promising phytochemicals with antioxidant and anti-inflammatory properties, including flavonoids. In this exploratory study, we aimed to assess the independent associations between dietary intake of total flavonoids and common flavonoid classes with the prevalence and 15-y incidence of AMD. In this population-based cohort study, 2856 adults aged ≥49 y at baseline and 2037 followed up 15 y later were included in prevalence and incidence analyses, respectively. Dietary intake was assessed by using a semiquantitative food-frequency questionnaire (FFQ). Estimates of the flavonoid content of foods in the FFQ were assessed by using the USDA Flavonoid, Isoflavone, and Proanthocyanidin databases. AMD was assessed from retinal photographs. In cross-sectional analysis, each 1-SD increase in total overall flavonoid intake was associated with a reduced likelihood of any AMD (multivariable-adjusted OR: 0.76; 95% CI: 0.58, 0.99). Each 1-SD increase in dietary intake of total flavonols and total flavanones was associated with reduced odds of the prevalence of any AMD [multivariable-adjusted OR (95% CI): 0.75 (0.58, 0.97) and 0.77 (0.60, 0.99), respectively]. A marginally significant trend (P=0.05) was observed between increasing the intake of total flavanone and hesperidin (from the first to the fourth quartile) and reduced likelihood of incident late AMD, after multivariable adjustment. Participants who reported ≥1 serving of oranges/d compared with those who never consumed oranges at baseline had a reduced risk of late AMD 15 y later (multivariable-adjusted OR: 0.39; 95% CI: 0.18, 0.85). Our findings suggest an independent and protective association between dietary intake of flavonoids and the likelihood of having AMD. Additional prospective cohort studies are needed to validate these findings.

Antioxidative and antibacterial properties of organically grown thyme(Thymus sp.) and basil (Ocimumbasilicum L.)

The biomass per plant and total phenolics (TPH) of ethanol extracts of 3 species of thyme, Thymus vulgaris , T. serpyllum , and T. citriodorus, and 3 varieties of basil (Ocimum basilicum ), Genovese, Thai, and Cinnamon, were investigated. All were grown organically. The 2 herbs that showed the greatest biomass were T. citriodorus ( 26.5 g/plant ) and O. basilicum var. Cinnamon (105 g/ plant). For these, total flavonoids (TFL), total flavones and flavonols (TFF), and total flavanones and dihydroflavonols (TFDH) were also determined for their ethanol extracts. Furthermore, the antioxidant potential (AOP) and antibacterial activity were determined against foodborne bacteria: Staphylococcus aureus , Listeria monocytogenes , Campylobacter jejuni , and verotoxin-producing Escherichia coli (VTEC). The highest TPH (36 mg chlorogenic acid equivalents per gram of fresh weight) was seen for T. citriodorus collected in 2010. The thyme ethanol extracts contained more TPH and TFL, and their subgroups of TFF and TFDH, than the ethanol extracts from basil, and had AOP comparable to the ethanol extracts from basil, although all of them were lower than the synthetic antioxidant, t-butylated hydroxytoluene. Drying of these herbs decreased TFF and TFDH, while TPH and TFL remained unchanged (for T. citriodorus ) or even increased (for Cinnamon basil), and AOP was higher than that of the ethanol extracts from the frozen herbs. The antimicrobial activities of these ethanol extracts depended mainly on the bacterial target. They were weak against gram-negative VTEC, while their effects against C. jejuni , S. aureus , and L. monocytogenes correlated with their TPH and chemical compositions.

Chemical and biological diversity of propolis samples from Bulgaria, Libya and Egypt

Introduction: Propolis is an important characteristic because it contains bioactive substances such as total phenolics, total flavones, flavonols, total flavanones and dihydroflavonols. Cancer is a large group of disorders characterized by uncontrolled cellular proliferation. It is one of the most devastating diseases all over the world. Recently, there is an increased interest in the clinical use of natural products as a safe, efficient, and economic therapeutic alternative. Honey bee products therapy, apitherapy, was used to control various diseases including cancer. Objectives: The primary objective of this study was to screen potential cytotoxic effects of propolis sample against different cancer types. Materials and Methods: Samples of propolis were collected from Bulgaria, Libya and Egypt and tested by MTT cell-based assay against liver (HEP-G2), breast (MCF-7) and colorectal (Caco-2) cancer cell lines. Results: The results showed that Libyan propolis proved to be most active among all tested propolis samples HEP-G2 (84.99%), MCF-7 (83.57%) and Caco-2 (79.63%). Conclusion: The results showed that propolis it is interesting agents that have valuable activities against HEP-G2, Caco-2 and MCF-7 with propolis being an effective agent that might be incorporated in cancer remedy regimens after further studies.

Flavonoid and Antioxidant Capacity of Propolis Prediction Using Near Infrared Spectroscopy

The use of propolis as a dietary supplement or as an ingredient in different food products is increasing, due to its antioxidant and bactericidal properties. These nutritional properties directly depend on its phenolic composition. For this reason, this study analysed the total contents of flavones and flavonols, flavanones and dihydroflavonols, and the antioxidant capacity by using the methods of ABTS and linoleic acid/β-carotene in 99 samples of propolis from Spain and Chile. A rapid method was developed for quantifying these parameters in raw propolis using near infrared (NIR) spectroscopy with a remote reflectance fibre-optic probe applied directly to the ground-up sample. The models developed allow for the determination of the total flavones and flavonols (0–183 mg quercetin/g propolis and 0–72 mg rutin/g propolis), of the total flavanones and dihydroflavonols (9–109 mg pinocembrin/g propolis extract), and of its antioxidant capacity by the ABTS method based on the reduction of the 2.2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation(0–3212.6 nmol Trolox/mg of propolis) and of linoleic acid/β-carotene (22–86% inhibition). The NIR spectroscopy models were applied in external validation to different samples of the calibration group, which led to the conclusion that the methods developed provide significantly identical data to the initial chemical data of reference.

Effect of Pasteurization on Flavonoids and Carotenoids in Citrus sinensis (L.) Osbeck cv. ‘Cara Cara’ and ‘Bahia’ Juices

Orange juice is considered an excellent dietary source of several bioactive compounds with beneficial properties for human health. Citrus sinensis Osbeck cv. 'Cara Cara' is a bud mutation originated from 'Washington' navel orange, also known as 'Bahia' navel orange. The ascorbic acid, flavonoid, and carotenoid contents in pasteurized and nonpasteurized Bahia and Cara Cara juices using two LC-MS/MS platforms were investigated. Higher ascorbic acid content was observed in Bahia compared to Cara Cara in both pasteurized and nonpasteurized juices. Total flavanones content as well as hesperidin levels were higher in Cara Cara with respect to Bahia pasteurized juice. Cara Cara was also characterized by a significantly higher and diversified carotenoid content compared to Bahia juice with a mixture of (Z)-isomers of lycopene, all-E-β-carotene, phytoene, and phytofluene isomers accounting for the highest carotenoid proportion. The exceptionally high carotenoid content of Cara Cara may be particularly interesting for nutritional or functional studies of uncommon carotenes in a citrus food matrix.

Effect of thermal processing on the profile of bioactive compounds and antioxidant capacity of fermented orange juice

Previously, we reported that alcoholic fermentation enhanced flavanones and carotenoids content of orange juice. The aim of this work was to evaluate the influence of pasteurization on the qualitative and quantitative profile of bioactive compounds and the antioxidant capacity of fermented orange juice. Ascorbic acid (203 mg/L), total flavanones (647 mg/L), total carotenoids (7.07 mg/L) and provitamin A (90.06 RAEs/L) values of pasteurized orange beverage were lower than those of fermented juice. Total phenolic remained unchanged (585 mg/L) and was similar to that of original juice. The flavanones naringenin-7-O-glucoside, naringenin-7-O-rutinoside, hesperetin-7-O-rutinoside, hesperetin-7-O-glucoside and isosakuranetin-7-O-rutinoside, and the carotenoids karpoxanthin and isomer, neochrome, lutein, ζ-carotene, zeaxanthin, mutatoxanthin epimers, β-cryptoxanthin and auroxanthin epimers were the major compounds. Pasteurization produced a decrease in antioxidant capacity of fermented juice. However, TEAC (5.45 mM) and ORAC (6353 μM) values of orange beverage were similar to those of original orange juice. The novel orange beverage could be a valuable source of bioactive compounds with antioxidant capacity and exert potential beneficial effects.

Study on effect of total flavanones of Sedum sarmentosum on apoptosis of hepatic stellate cells and its mechanism

To study the effect of total flavanones of Sedum sarmentosum (SSTF) on the apoptosis of rat hepatic stellate cells (HSC-T6) and its mechanism. Different concentrations of SSTF and HSC-T6 cells were co-cultured for different period of time. The MTT assay was used to detect the inhibitory effect of SSTF on the proliferation of HSC-T6 cells. The flow cytometry Annexin-V/PI double staining method was adopted to detect SSTF's effect on HSC-T6 cell apoptosis. Western blotting and Real-time PCR methods were applied to observe the effect on the protein and mRNA expressions of apoptosis-related cytokines Bcl-2, Bax and Caspase-3. SSTF significantly inhibited HSC-T6 cell proliferation and induced cell apoptosis in a dose and time dependent manner. According to Western blotting result, SSTF promoted apoptosis by inhibiting Bcl-2, Bax and promoting the protein expression of Caspase-3; according to a further Real-time PCR study, Bcl-2 mRNA levels can inhibit Bcl-2 and promote Bax and Caspase-3 expressions. SSTF has the effect of promoting the apoptosis of HSC-T6 mainly by inhibiting Bcl-2 and promoting protein and mRNA expressions of Bax and caspase-3.

Urinary Excretion of Select Dietary Polyphenol Metabolites Is Associated with a Lower Risk of Type 2 Diabetes in Proximate but Not Remote Follow-Up in a Prospective Investigation in 2 Cohorts of US Women1–3

Background: Polyphenols are phytochemicals that possess antioxidant and anti-inflammatory properties and improve glucose metabolism in animal experiments, although data from prospective epidemiologic studies examining polyphenol intakes in relation to type 2 diabetes (T2D) risk are inconsistent.Objectives: We examined urinary excretion of select flavonoid and phenolic acid metabolites, as biomarkers of intake, in relation to T2D risk.Methods: Eight polyphenol metabolites (naringenin, hesperetin, quercetin, isorhamnetin, catechin, epicatechin, caffeic acid, and ferulic acid) were quantified in spot urine samples by liquid chromatography/mass spectrometry among 1111 T2D case-control pairs selected from the Nurses’ Health Study (NHS) and NHSII.Results: Higher urinary excretion of hesperetin was associated with a lower T2D risk after multivariate adjustment: the OR comparing top vs. bottom quartiles was 0.68 (95% CI: 0.49, 0.96), although a linear trend was lacking (P = 0.30). The other measured polyphenols were not significantly associated with T2D risk after multivariate adjustment. However, during the early follow-up period [≤4.6 y (median) since urine sample collection], markers of flavanone intakes (naringenin and hesperetin) and flavonol intakes (quercetin and isorhamnetin) were significantly associated with a lower T2D risk. The ORs (95% CIs) comparing extreme quartiles were 0.61 (0.39, 0.98; P-trend: 0.03) for total flavanones and 0.55 (0.33, 0.92; P-trend: 0.04) for total flavonols (P-interaction with follow-up length: ≤0.04). An inverse association was also observed for caffeic acid during early follow-up only: the OR was 0.52 (95% CI: 0.32, 0.84; P-trend: 0.03). None of these markers was associated with T2D risk during later follow-up. Metabolites of flavan-3-ols and ferulic acid were not associated with T2D risk in either period.Conclusions:These results suggest that specific flavonoid subclasses, including flavanones and flavonols, as well as caffeic acid, are associated with a lower T2D risk in relatively short-term follow-up but not during longer follow-up. Substantial within-person variability of the metabolites in single spot urine samples may limit the ability to capture associations with long-term disease risk.

Abstract P320: Dietary Flavonoid Intake and Ischemic Stroke

Introduction: Diets rich in plant-based foods have been associated with lower stroke risk. Plant-based foods contain a variety of potentially cardioprotective compounds, including flavonoids. We assessed the hypothesis that total flavonoid and flavonoid subclass intakes are associated with incident ischemic stroke in a population-based cohort oversampled for non-Hispanic blacks and Stroke Belt residents. Methods: Between 2003 and 2007, REGARDS enrolled black and white Americans age ≥ 45 years. Participants were 20,413 men and women who completed a Block 98 food frequency questionnaire (FFQ) and without stroke at baseline. Total flavonoid and flavonoid subclass (anthocyanidin, flavan-3-ol, flavanone, flavonol, flavone, proanthocyanidin and isoflavone) intakes were estimated using the food consumption reported by the FFQ and the flavonoid contents of each food using USDA databases. Incident strokes were captured by participant report and adjudicated by experts. Quintiles of flavonoid intake were examined as predictors of incident stroke using Cox regression models using the first quintile as the referent. Tests for trend used the quintile medians. Results: Adjusting for age and caloric intake, there was a statistically significant inverse association between total flavonoid intake and ischemic stroke (Q5 v Q1: HR=0.68; 95% CI=0.51, 0.90; p-trend=0.04) however, this association weakened after additional adjustment for demographic, socioeconomic and health behavior factors as well as self-reported CHD at baseline (Q5 v Q1: HR=0.77; 95% CI=0.58, 1.03; p-trend=0.31). A similar pattern was seen for flavanones (age, energy adjusted HR=0.74; 95% CI= 0.57, 0.95; p-trend=0.02; fully adjusted HR= 0.82; 95%CI=0.65, 1.05; p-trend=0.06). Effect estimates for total flavonoids, flavanones, proanthocyanidins, and isoflavones, suggested a protective, though nonlinear association with risk reduction emerging at the second quintile, though these did not achieve statistical significance (total flavonoids, fully adjusted HR (95% CI): Q2= 0.80 (0.61, 1.04); Q3= 0.85 (0.65, 1.11); Q4=0.92 (0.70, 1.19); Q5= 0.77 (0.58, 1.03)). Total flavonoid and flavanone intake were significantly associated with IS in fully adjusted models in women (total: Q5 v Q1 HR=0.62; 95% CI= 0.41, 0.94; p-trend=0.15; flavanones HR=0.65; 95% CI=0.44, 0.95; p-trend=0.03) but not in men (total: Q5 v Q1 HR=0.95; 95% CI= 0.63, 1.42; flavanones HR=0.80; 95% CI=0.58, 1.09; p-interaction=0.67). There was no effect modification by race or region of residence. Conclusion: Total dietary flavonoids and flavanones are associated with a reduction in risk of incident ischemic stroke, particularly in women. The emergence of a protective effect at the second quintile for total flavonoids, flavanones, proanthocyanidins and isoflavones is consistent with previous studies of dietary flavonoid intake and CVD mortality.