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Flavonoids such as quercetin and its glucosides, especially isoquercitrin are well known as anti-inflammatory, anti-allergic, and anti-carcinogenic, etc. The safety of isoquercitrin formulations needs to be established prior to their use in functional food applications. The mutagenicity and genotoxicity of the IQC-γCD inclusion complex were assessed with three standard assays of the bacterial reverse mutation assay (Ames test) and using a combined in-vivo micronucleus and comet assay under the Organisation for Economic Co-operation and Development (OECD) guidelines. In combined rat bone marrow micronucleus and rat liver comet assay performed in male Sprague Dawley (SD) rats, the various doses of IQC-γCD inclusion complex (max. 2000 mg/kg bw) and positive controls ethyl methanesulfonate (EMS) and mitomycin C (MMC), respectively, and negative control (vehicle) were administrated. The results of the Salmonella typhimurium mutagenicity assay (strains TA100, TA1535, WP2uvrA, TA98, and TA1537) after exposure to the IQC-γCD inclusion complex with the absence and presence of the metabolic activation system (S9 fraction from rat liver) revealed a weakly positive response but with no biologically relevant mutagenicity at the conditions examined according to recommended regulatory guidelines. The combined micronucleus and comet assay results reveal that the IQC-γCD inclusion complex did not induce in-vivo genotoxic potential or indication of any oxidative DNA damage in rat liver tissues. Altogether, considering the results of the study, it is unlikely that the consumption of IQC-γCD inclusion complex as food or supplement would present any concern for humans regarding the mutagenicity and genotoxicity.

The protein kinase mechanistic target of rapamycin (mTOR) performs diverse cellular functions through 2 distinct multiprotein complexes, mTOR complex (mTORC)1 and 2. Numerous studies using rapamycin, an mTORC1 inhibitor, have implicated a role for mTORC1 in several types of heart disease. People with diabetes are more susceptible to heart failure. mTORC1 activity is increased in the diabetic heart, but its functional significance remains controversial. To investigate the role of mTORC1 in the diabetic heart, we crossed OVE26 type 1 diabetic mice with transgenic mice expressing a constitutively active mTOR (mTORca) or kinase-dead mTOR (mTORkd) in the heart. The expression of mTORca or mTORkd affected only mTORC1 but not mTORC2 activities, with corresponding changes in the activities of autophagy, a cellular degradation pathway negatively regulated by mTORC1. Diabetic cardiac damage in OVE26 mice was dramatically reduced by mTORca but exacerbated by mTORkd expression as assessed by changes in cardiac function, oxidative stress, and myocyte apoptosis. These findings demonstrated that the enhanced mTORC1 signaling in the OVE26 diabetic heart was an adaptive response that limited cardiac dysfunction, suggesting that manipulations that enhance mTORC1 activity may reduce diabetic cardiac injury, in sharp contrast to the results previously obtained with rapamycin.-Xu, X., Kobayashi, S., Timm, D., Huang, Y., Zhao, F., Shou, W., Liang, Q. Enhanced mTOR complex 1 signaling attenuates diabetic cardiac injury in OVE26 mice.

Flavonoids such as quercetin and its glycoside Isoquercitrin and are abundantly present in the diet and have various pharmacological effects. However, limited data about its potential toxicity is available. In this study, we aim to evaluate the subchronic toxicity of the isoquercitrin-γ-cyclodextrin (IQC-γCD) molecular inclusion complex (SunActive® QCD/EN) in Sprague-Dawley (SD) rats. The IQC-γCD was administrated orally to 40 male and 40 female SD rats at dietary doses up to 5.0 % for 13 consecutive weeks. During the experiment periods, the general clinical signs, mortality, hematological, urinalysis values, biochemical, and histopathological parameters were examined. All animals survived until the scheduled necropsy, and no statistically significant or clinical sign of toxicologically relevant differences including pathology parameters, and histopathological endpoints were observed in any of the IQC-γCD treatment groups, compared with the control group. However, certain observations were noted in the male rats treated with the highest concentration (5.0 %), but these were not seen in female rats. A slight inhibition of weight gain was observed, probably linked to a fall in red blood cells, and hematocrit index in female rats. Statistically significant changes were noted in some clinical measures, such as plasma bilirubin level, alkaline phosphatase total bile acid without evidence of systemic clinical toxicity. The results support no observed adverse effect level (NOAEL) of IQC-γCD of 5.0 % in the diet for males (3338.55 mg/kg/day), and 3.0 % in the diet for females (2177.33 mg/kg/day) SD rats. Therefore, in this 13 weeks repeated-dose SD rat study there were no treatment-related adverse clinical or pathological findings for IQC-γCD of 5.0 % in the diet for males, and 3.0 % in the diet for females SD rats. The results of the present study support the safe use of IQC-γCD as a functional food, food additive, and natural ingredient.

Isoquercitrin has a higher bioavailability than quercetin and has various pharmacological effects. In the present study, we aim to elucidate the structure of the novel isoquercitrin-γ-cyclodextrin (IQC-γCD) inclusion complex derived through controlled enzymatic hydrolysis of rutin into isoquercitrin in-situ included in γ-cyclodextrin. Several vibrational, electronic and analytical spectral measurement techniques (FTIR, 1H-NMR, 13C-NMR, UV-Vis, DSC, PXRD, Raman spectroscopy, and SEM) were employed. The detailed structural comparison of the IQC-γCD inclusion complex with isolated isoquercitrin revealed the shielding of isoquercitrin –OH groups inside the γ-CD cavity, and thus, confirmed the successful formation of the inclusion complex that exhibit distinct spectroscopic features from both guest and host molecules. The phase-solubility studies showed that isoquercitrin formed a 1:1 stoichiometric inclusion complex with γ-CD. The aqueous solubility of isoquercitrin was significantly enhanced by complexation with γ-CD complex possibly due to increased isoquercitrin dissolution rate compared to the isolated isoquercitrin. The IQC-γCD inclusion could have enhanced pharmacokinetics that will be useful for future applications in functional foods and health benefits.

Catechins are a part of the chemical family of flavonoids, a naturally occurring antioxidant, and a secondary metabolite in certain plants. Green tea catechins are well recognized for their essential anti-inflammatory, photo-protective, antioxidant, and chemo-preventive functions. Ultraviolet radiation is a principal cause of damage to the skin. Studies observed that regular intake of green tea catechins increased the minimal dose of radiation required to induce erythema. The objectives of this systematic review and meta-analysis are to determine the effectiveness of green tea catechins in cutaneous erythema and elucidate whether green tea catechin consumption protects against erythema (sunburn) inflammation. A comprehensive literature search was conducted to identify the relevant studies. Two researchers carried out independent screening, data extraction, and quality assessment according to the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). The pooled effect of green tea catechins on protection against erythema was assessed using approaches fixed-effects or random-effects model to quantify the effectiveness of green tea catechins in the erythema dose–response. Studies not be included in meta-analyses were summarized narratively. Six randomized controlled studies of enrolled studies regularly administrated green tea catechins orally for 6 to 12 weeks involving healthy volunteers comprising a total of 100 participants were included in the analysis. The results revealed green tea catechins have favorable protection against erythema inflammation even at increased minimal erythema dose (MED) of ultraviolet radiation. Meta-analysis results confirm oral supplementation of green tea catechins is highly effective at low-intensity ultraviolet radiation-induced erythema response (MED range; 1.25–1.30) compared to placebo, showing a significant pooling difference (p = 0.002) in erythema index (SMD: −0.35; 95% CI, −0.57 to −0.13; I2 = 4%, p = 0.40) in the random-effects model. The pro-inflammatory signaling pathways through oral supplementation with green tea catechins are an attractive strategy for photo-protection in healthy human subjects and could represent a complementary approach to topical sunscreens. Therefore, studies that involved green tea catechin in topical applications to human subjects were also evaluated separately, and their meta-analysis is presented as a reference. The evidence indicates that regular green tea catechin supplementation is associated with protection against UV-induced damage due to erythema inflammation.

OBJECTIVES: The widespread impact of the gut microbiota in human health has emerged in recent years. Changes in diet and exercise can alter the gut microbiomes of active athletes. We performed a randomized, controlled study to evaluate the relationship between the partially hydrolyzed guar gum (PHGG) prebiotic dietary fiber and the relative abundance of the gut microbiomes in the context of changes in lifestyle-related factors, and their significant correlation with fecal defecation characteristics in healthy athletes. METHODS: Subjects followed a daily 6 grams dietary intake of either PHGG or placebo for four weeks, following a three weeks washout period, subjects followed another four weeks of crossover alternative administration. Fecal defecation characteristics were assessed using a questionnaire along with the quality of life (QOL) questions and gut microbiome abundance was determined by 16S rRNA gene sequencing and real-time PCR analysis. RESULTS: The alteration in gastrointestinal microbiomes relative abundance was correlated to representative changes in fecal defecation characteristics, especially in ameliorating diarrhea (P = 0.035) and fecal excretory feeling (P = 0.038). The PHGG intake led to a significant increase in phylum Actinobacterium (P = 0.04), along with a significant decrease in Bacteroidetes (P = 0.036). A trending decrease in Firmicutes (P = 0.09) Awas noticed. Also, a significant alteration in the relative abundance of Bifidobacterium (P = 0.047) and Clostridium subcluster XI (P = 0.044) were observed with PHGG intake compared with placebo. Principal component analysis and hierarchical clustering analysis represented a clear overview of the distribution of quality of life covariates evaluated in the study. CONCLUSIONS: Improved diarrhea was associated with the relative abundance of phylum Firmicutes/Bacteroidetes ratio and genera Bacteroides/Prevotella ratio for the PHGG intervention compared to placebo. The finding reveals that even at relatively low dosage, intake of prebiotic PHGG fiber modulates gut microbiomes, and thus improves gastrointestinal health. Overall, the quality of lifestyle factors was significantly improved with PHGG consumption. FUNDING SOURCES: Taiyo Kagaku, University of Tsukuba, and Otsuma Women's University equally contributed to the study.

This study compared satiety after high protein pasta (16 g protein, 6 g fiber), high fiber pasta (11 g protein, 8 g fiber) or control pasta (11 g protein, 6 g fiber) in a randomized, placebo-controlled, double-blind crossover trial. Participants were 36 healthy and men and women from the University of Minnesota campus. Fasted men and women ate calorie controlled, but macronutrient different pastas at 12:00 pm along with 500 mL of water. The primary outcome was satiety assessed by Visual Analogue Scales at 0, 15, 30, 45, 60, 90, 120, and 180 min daily after consuming the pastas. Secondary outcomes were calories consumed at an ad libitum snack at 3:00 pm, calories from food intake, gastrointestinal tolerance, and palatability. No differences were found among the pasta treatments for satiety, snacking, or gastrointestinal tolerance. Men ate significantly more calories for the rest of the (P = 0.007) after the high protein pasta versus the high fiber pasta (1701 ± 154 compared with 1083 ± 154) with control pasta being intermediate to the other treatments. No significant differences were found for gastrointestinal tolerance, but the palatability ratings showed the high protein pasta was less tasty (P = 0.03) and less pleasant (P = 0.01) than the other 2 pastas. Satisfaction was positively associated with pleasantness and negatively associated with aftertaste. Our results do not support the idea that high protein or high fiber pasta produces a greater satiety response compared to pasta with lower amounts of either nutrient. It is likely that since pasta is already a very satiating food, the subjects were unable to differentiate between the 3 conditions.

Cardiac autophagy is inhibited in type 1 diabetes. However, it remains unknown if the reduced autophagy contributes to the pathogenesis of diabetic cardiomyopathy. We addressed this question using mouse models with gain- and loss-of-autophagy. Autophagic flux was inhibited in diabetic hearts when measured at multiple time points after diabetes induction by streptozotocin as assessed by protein levels of microtubule-associated protein light chain 3 form 2 (LC3-II) or GFP-LC3 puncta in the absence and presence of the lysosome inhibitor bafilomycin A1. Autophagy in diabetic hearts was further reduced in beclin 1- or Atg16-deficient mice but was restored partially or completely by overexpression of beclin 1 to different levels. Surprisingly, diabetes-induced cardiac damage was substantially attenuated in beclin 1- and Atg16-deficient mice as shown by improved cardiac function as well as reduced levels of oxidative stress, interstitial fibrosis, and myocyte apoptosis. In contrast, diabetic cardiac damage was dose-dependently exacerbated by beclin 1 overexpression. The cardioprotective effects of autophagy deficiency were reproduced in OVE26 diabetic mice. These effects were associated with partially restored mitophagy and increased expression and mitochondrial localization of Rab9, an essential regulator of a non-canonical alternative autophagic pathway. Together, these findings demonstrate that the diminished autophagy is an adaptive response that limits cardiac dysfunction in type 1 diabetes, presumably through up-regulation of alternative autophagy and mitophagy.

Doxorubicin (DOX) is a potent, commonly used anthracycline antibiotic for a wide range of cancers, but its dose is limited by its strong cardiotoxic effects. The glucose analog 2-deoxy-D-glucose (2-DG) has been shown to enhance the antitumor efficacy of DOX in tumor cell lines and in animals. However, the cardiac effects of 2-DG in these experiments were not determined. In the current study, we examined whether 2-DG could protect from DOX cardiotoxicity in a BALB/c mouse breast cancer model. A total of 32 mice were injected with 10 5 4T1 mouse mammary epithelial tumor cells in the right hind leg. The tumor was allowed to progress for 1 week before dividing the mice into four groups: saline, 2-DG, DOX, and 2-DG with DOX treatment. 2-DG was given 150 mg/kg i.p. Monday through Friday; DOX was given 5 mg/kg i.p. Wednesday. The study was conducted for 3 weeks and echocardiography was performed the day before sacrifice. Two of the eight mice in the DOX group died before echocardiography, while none died in the 2-DG with DOX group. Echocardiography indicated similar cardiac function between saline and 2-DG groups as measured by fractional shortening (36.3±1.31% vs 37.7±0.942%, p>0.05). DOX markedly reduced cardiac function, which was almost completely recovered by 2-DG (25.1±1.06% vs 36.7±1.76%, p0.05). Nonetheless, 2-DG largely eliminated DOX-induced apoptosis in the heart as shown by a DNA laddering assay. 2-DG or DOX alone increased cardiac autophagic flux as measured by the difference in LC3-II protein levels in the absence and presence of the lysosomal inhibitor, bafilomycin A1. Paradoxically, autophagic flux was not notably elevated when mice were treated with 2-DG and DOX simultaneously. These results demonstrate the ability of 2-DG to reduce DOX cardiotoxicity without affecting its antitumor activity, suggesting that 2-DG can improve the therapeutic window for DOX, allowing greater flexibility in designing different regimens for treating cancers.

Caloric restriction (CR) is a robust dietary intervention known to delay age-related heart disease. CR is able to antagonize cardiac remodeling in animal and human under various pathological conditions. However, the direct effect of CR on the heart at basal physiological state is not well characterized. In this study, we examined the impact of CR on cardiac homeostasis and explored the signaling mechanisms that mediate the cardiac effect of CR. Male C57BL/6J mice underwent 20% CR, i.e. 20% less food than ad libitum (AL), for 2 weeks and 40% CR for another 2 weeks. This CR regimen caused a roughly 20% decrease in heart weight and myocyte cross-sectional area. CR diminished the activity of the mammalian target of rapamycin ( mTOR) and accelerated autophagic flux. To determine the functional role of mTOR inhibition in CR-induced heart size reduction, we used transgenic mice that express a constitutively active mTOR (mTORca) in the heart. CR did not inhibit cardiac mTOR signaling in mTORca mice as it did in wild type (WT) mice. As a result, the ability of CR to reduce heart size in WT mice was severely impaired in mTORca mice. Specifically, CR reduced the heart weight by 23.1% in WT mice (p0.05 vs AL). Strikingly, when animals were treated with the mTOR inhibitor rapamycin, CR decreased heart weight in both WT and mTORca mice to the same extent, strongly suggesting that mTOR inhibition is required for CR to exert its cardiac effect. Autophagy is a cellular degradation pathway that may contribute to CR-induced heart size reduction. Surprisingly, CR can still decrease heart weight in 2 different autophagy-deficient mouse models, namely, beclin 1 heterozygous knockout mice and ATG16L1 hypomorphic mice. Nonetheless, cardiac function in these mice was markedly deteriorated during CR as indicated by decreased fractional shortening (Beclin 1+−: AL 37.9±2.8 vs CR 29.6±2.1, p

Caloric restriction (CR) is a dietary intervention known to enhance cardiovascular health. The glucose analog 2-deoxy-d-glucose (2-DG) mimics CR effects in several animal models. However, whether 2-DG is beneficial to the heart remains obscure. Here, we tested the ability of 2-DG to reduce cardiomyocyte death triggered by doxorubicin (DOX, 1 μm), an antitumor drug that can cause heart failure. Treatment of neonatal rat cardiomyocytes with 0.5 mm 2-DG dramatically suppressed DOX cytotoxicity as indicated by a decreased number of cells that stained positive for propidium iodide and reduced apoptotic markers. 2-DG decreased intracellular ATP levels by 17.9%, but it prevented DOX-induced severe depletion of ATP, which may contribute to 2-DG-mediated cytoprotection. Also, 2-DG increased the activity of AMP-activated protein kinase (AMPK). Blocking AMPK signaling with compound C or small interfering RNA-mediated knockdown of the catalytic subunit markedly attenuated the protective effects of 2-DG. Conversely, AMPK activation by pharmacological or genetic approach reduced DOX cardiotoxicity but did not produce additive effects when used together with 2-DG. In addition, 2-DG induced autophagy, a cellular degradation pathway whose activation could be either protective or detrimental depending on the context. Paradoxically, despite its ability to activate autophagy, 2-DG prevented DOX-induced detrimental autophagy. Together, these results suggest that the CR mimetic 2-DG can antagonize DOX-induced cardiomyocyte death, which is mediated through multiple mechanisms, including the preservation of ATP content, the activation of AMPK, and the inhibition of autophagy.

Doxorubicin (DOX) is a potent anti-tumor drug known to cause heart failure. The transcription factor GATA4 antagonizes DOX-induced cardiotoxicity. However, the protective mechanism remains obscure. Autophagy is the primary cellular pathway for lysosomal degradation of long-lived proteins and organelles, and its activation could be either protective or detrimental depending on specific pathophysiological conditions. Here we investigated the ability of GATA4 to inhibit autophagy as a potential mechanism underlying its protection against DOX toxicity in cultured neonatal rat cardiomyocytes. DOX markedly increased autophagic flux in cardiomyocytes as indicated by the difference in protein levels of LC3-II (microtubule-associated protein light chain 3 form 2) or numbers of autophagic vacuoles in the absence and presence of the lysosomal inhibitor bafilomycin A1. DOX-induced cardiomyocyte death determined by multiple assays was aggravated by a drug or genetic approach that activates autophagy, but it was attenuated by manipulations that inhibit autophagy, suggesting that autophagy contributes to DOX cardiotoxicity. DOX treatment depleted GATA4 protein levels, which predisposed cardiomyocytes to DOX toxicity. Indeed, GATA4 gene silencing triggered autophagy that rendered DOX more toxic, whereas GATA4 overexpression inhibited DOX-induced autophagy, reducing cardiomyocyte death. Mechanistically, GATA4 up-regulated gene expression of the survival factor Bcl2 and suppressed DOX-induced activation of autophagy-related genes, which may likely be responsible for the anti-apoptotic and anti-autophagic effects of GATA4. Together, these findings suggest that activation of autophagy mediates DOX cardiotoxicity, and preservation of GATA4 attenuates DOX cardiotoxicity by inhibiting autophagy through modulation of the expression of Bcl2 and autophagy-related genes.

Objective: Fiber supplements may increase fiber intake for those unable to reach recommended amounts through the diet. Colonic microbiota ferment fibers, producing metabolites such as short chain fatty acids (SCFAs) and gases. SCFAs and low colonic pH provide potential health benefits; however excess gas has decreased tolerance In Vivo. Fiber source influences fermentation rates and physiological effects. This study compared fermentation and microbiota profiles of three dietary fibers after digestion with salivary amylase and pepsin to mimic physiologic fermentation and to predict physiological benefits and tolerance In Vivo. Methods: Wheat dextrin (WD), inulin, and partially hydrolyzed guar gum (PHGG) underwent In Vitro digestion and fermentation. Each fiber (0.5 g) was fermented in triplicate including a control group with no fiber for 0, 4, 8, 12, and 24 h and was used for analysis of pH, gas volume, hydrogen and methane gases, and SCFA concentrations. Quantitative PCR was used to measure bifidobacteria and lactobacilli CFUs at 24 h. Data analysis was completed using an ANOVA procedure by SAS. Statistical significance was achieved when P-value < 0.05. No statistical analysis was done on microbiota results due to small sample size. Summary of Results: WD produced the least volume of gas during fermentation at 8, 12, and 24 h (P < 0.0001), while inulin produced the most at 8 h (P < 0.0001). Inulin reached its lowest pH value at 8 h (5.94 ± 0.05), PHGG at 12 h (5.98 ± 0.02), and WD at 24 h (6.17 ± 0.05). SCFA concentrations were not different, however differences in the proportion of SCFAs produced were observed at 24 h. Inulin andWD had a larger proportion of acetate (30% and 29% respectively), compared to PHGG (23%) (P < 0.0001). Propionate proportion from PHGG (53%) was larger than WD (48%) and inulin (33%) (P < 0.0001). Butyrate proportion from inulin (37%) was higher than PHGG (24%) and WD (23%) (P < 0.0001). A preliminary microbial analysis (CFU log 10/uL) showed WD with the largest CFU for bifidobacteria (6.12) and lactobacilli (7.15) compared with the control (4.92 and 6.35 respectively). Conclusions: Fermentation of WD produced less gas than inulin or PHGG, which may lead to better tolerance In Vivo. The fibers produced different proportions of acetate, propionate and butyrate and fecal pH values. Through the 24 h, pH values for WD consistently declined. Decreases in colonic pH may promote growth of beneficial bacteria. Butyrate is known to be a beneficial fuel source for colonocytes. The increased levels of bifidobacteria and lactobacilli suggest possible prebiotic effects that warrant further investigation. More research is required to determine the physiological benefits and tolerance of these fibers In Vivo. This study was supported by a research grant from Novartis Consumer Health Inc. Parsippany, New Jersey, USA.

G A A b st ra ct s tension recordings of KCland bethanechol-induced contractions in circular orientated myenteric strips. Intracellular calcium was determined by fluorescencemicroscopy in isolated smooth muscle cells loaded with fura-2-AM (ExWL 340/380nm, EmWL 510nm) and calcium changes were expressed as the ratio between elicited fluorescence at 340nm and 380nm (F340/380). Mitochondrial membrane potential was measured in isolated colonic smooth muscle cells using the cell-permeant green fluorescent dye rhodamine 123 Results: Aging caused an increase in caffeine-induced Ca2+ release (140 % respect to adult cells) and a decrease in mitochondrial membrane potential, as indicated by the reduction of the heterogeneity of the rhodamine123 fluorescence signal in isolated cells. When mitochondria function was impaired using rotenone (1 μM) plus oligomycin (5 μM) the amplitude of Ca2+ release was significantly reduced (by 45%) and the [Ca2+]i decay showed a slower rate in senescent cells. Melatonin treatment protected from the deleterious effects of these agents. These changes in Ca2+ homeostasis did not translate into alterations in contractility, since pretreatment of both proximal and distal circular myenteric strips with rotenone, oligomicin of both for 30 min did not modify significantly the contractile response to neither KCl (60 mM) nor bethanechol (100 μM). Conclusion: Mitochondria play a more important role in Ca2+ homeostasis in aged than adult cells, however these changes are not enough to modify contractility, which suggest that in colonic smooth muscle mitochondrial respiratory chain is not essencial for contraction and that more sources of ATP than ATP synthase coexist in these cells. Supported by BFU2007-60563 and JEX