Quercetin supplementation and its effect on human monocyte gene expression profiles in vivo

Drug repurposing based on the similarity gene expression signatures to explore for potential indications of quercetin: a case study of multiple sclerosis

Quercetin (QR) is a natural flavonol compound widely distributed in the plant kingdom with extensive pharmacological effects. To find the potential clinical indications of QR, 156 differentially expressed genes (DEGs) regulated by QR were obtained from the Gene Expression Omnibus database, and new potential pharmacological effects and clinical indications of QR were repurposed by integrating compounds with similar gene perturbation signatures and associated-disease signatures to QR based on the Connectivity Map and Coexpedia platforms. The results suggested QR has mainly potential therapeutic effects on multiple sclerosis (MS), osteoarthritis, type 2 diabetes mellitus, and acute leukemia. Then, MS was selected for subsequent animal experiments as a representative potential indication, and it found that QR significantly delays the onset time of classical MS model animal mice and ameliorates the inflammatory infiltration and demyelination in the central nervous system. Combined with network pharmacology technology, the therapeutic mechanism of QR on MS was further demonstrated to be related to the inhibition of the expression of inflammatory cytokines (TNF-α, IL-6, IL-1β, IFN-γ, IL-17A, and IL-2) related to TNF-α/TNFR1 signaling pathway. In conclusion, this study expanded the clinical indications of QR and preliminarily confirmed the therapeutic effect and potential mechanism of QR on MS.

Eat4Genes: a bioinformatic rational gene targeting app and prototype model for improving human health

Introduction and aims

Dietary Rational Gene Targeting (DRGT) is a therapeutic dietary strategy that uses healthy dietary agents to modulate the expression of disease-causing genes back toward the normal. Here we use the DRGT approach to (1) identify human studies assessing gene expression after ingestion of healthy dietary agents with an emphasis on whole foods, and (2) use this data to construct an online dietary guide app prototype toward eventually aiding patients, healthcare providers, community and researchers in treating and preventing numerous health conditions.

Methods

We used the keywords "human", "gene expression" and separately, 51 different dietary agents with reported health benefits to search GEO, PubMed, Google Scholar, Clinical trials, Cochrane library, and EMBL-EBI databases for related studies. Studies meeting qualifying criteria were assessed for gene modulations. The R-Shiny platform was utilized to construct an interactive app called "Eat4Genes".

Results

Fifty-one human ingestion studies (37 whole food related) and 96 key risk genes were identified. Human gene expression studies were found for 18 of 41 searched whole foods or extracts. App construction included the option to select either specific conditions/diseases or genes followed by food guide suggestions, key target genes, data sources and links, dietary suggestion rankings, bar chart or bubble chart visualization, optional full report, and nutrient categories. We also present user scenarios from physician and researcher perspectives.

Conclusion

In conclusion, an interactive dietary guide app prototype has been constructed as a first step towards eventually translating our DRGT strategy into an innovative, low-cost, healthy, and readily translatable public resource to improve health.

Mechanistic insights into dietary (poly)phenols and vascular dysfunction-related diseases using multi-omics and integrative approaches: Machine learning as a next challenge in nutrition research

Dietary (poly)phenols have been extensively studied for their vasculoprotective effects and consequently their role in preventing or delaying onsets of cardiovascular and metabolic diseases. Even though early studies have ascribed the vasculoprotective properties of (poly)phenols primarily on their putative free radical scavenging properties, recent data indicate that in biological systems, (poly)phenols act primarily through genomic and epigenomic mechanisms. The molecular mechanisms underlying their health properties are still not well identified, mainly due to the use of physiologically non-relevant conditions (native molecules or extracts at high concentrations, rather than circulating metabolites), but also due to the use of targeted genomic approaches aiming to evaluate the effect only on few specific genes, thus preventing to decipher detailed molecular mechanisms involved. The use of state-of-the-art untargeted analytical methods represents a significant breakthrough in nutrigenomics, as these methods enable detailed insights into the effects at each specific omics level. Moreover, the implementation of multi-omics approaches allows integration of different levels of regulation of cellular functions, to obtain a comprehensive picture of the molecular mechanisms of action of (poly)phenols. In combination with bioinformatics and the methods of machine learning, multi-omics has potential to make a huge contribution to the nutrition science. The aim of this review is to provide an overview of the use of the omics, multi-omics, and integrative approaches in studying the vasculoprotective properties of dietary (poly)phenols and address the potentials for use of the machine learning in nutrigenomics.

The neuroprotective effects of polyphenols, their role in innate immunity and the interplay with the microbiota

Neurodegenerative disorders, particularly in the elderly population, represent one of the most pressing social and health-care problems in the world. Besides the well-established role of both oxidative stress and inflammation, alterations of the immune response have been found to be closely linked to the development of neurodegenerative diseases. Interestingly, various scientific evidence reported that an altered gut microbiota composition may contribute to the development of neuroinflammatory disorders. This leads to the proposal of the concept of the gut-brain-immune axis. In this scenario, polyphenols play a pivotal role due to their ability to exert neuroprotective, immunomodulatory and microbiota-remodeling activities. In the present review, we summarized the available literature to provide a scientific evidence regarding this neuroprotective and immunomodulatory effects and the interaction with gut microbiota of polyphenols and, the main signaling pathways involved that can explain their potential therapeutic application in neurodegenerative diseases.

Potential therapeutic applications of phytoconstituents as immunomodulators: Pre-clinical and clinical evidences

Autoimmune and infectious diseases are the major public health issues and have gained great attention in the last few years for the search of new agents with therapeutic benefits on the host immune functions. In recent years, natural products (NPs) have been studied broadly for their multi-targeted activities under pathological conditions. Interestingly, several attempts have been made to outline the immunomodulatory properties of NPs. Research on in-vitro and in-vivo models have shown the immunomodulatory activity of NPs, is due to their antiinflammatory property, induction of phagocytosis and immune cells stimulation activity. Moreover, studies on humans have suggested that phytomedicines reduce inflammation and could provide appropriate benefits either in single form or complex combinations with other agents preventing disease progression, subsequently enhancing the efficacy of treatment to combat multiple malignancies. However, the exact mechanism of immunomodulation is far from clear, warranting more detailed investigations on their effectiveness. Nevertheless, the reduction of inflammatory cascades is considered as a prime protective mechanism in a number of inflammation regulated autoimmune diseases. Altogether, this review will discuss the biological activities of plant-derived secondary metabolites, such as polyphenols, alkaloids, saponins, polysaccharides and so forth, against various diseases and their potential use as an immunomodulatory agent under pathological conditions.

Therapeutic Potential of Flavonoids in Pain and Inflammation: Mechanisms of Action, Pre-Clinical and Clinical Data, and Pharmaceutical Development

Pathological pain can be initiated after inflammation and/or peripheral nerve injury. It is a consequence of the pathological functioning of the nervous system rather than only a symptom. In fact, pain is a significant social, health, and economic burden worldwide. Flavonoids are plant derivative compounds easily found in several fruits and vegetables and consumed in the daily food intake. Flavonoids vary in terms of classes, and while structurally unique, they share a basic structure formed by three rings, known as the flavan nucleus. Structural differences can be found in the pattern of substitution in one of these rings. The hydroxyl group (-OH) position in one of the rings determines the mechanisms of action of the flavonoids and reveals a complex multifunctional activity. Flavonoids have been widely used for their antioxidant, analgesic, and anti-inflammatory effects along with safe preclinical and clinical profiles. In this review, we discuss the preclinical and clinical evidence on the analgesic and anti-inflammatory proprieties of flavonoids. We also focus on how the development of formulations containing flavonoids, along with the understanding of their structure-activity relationship, can be harnessed to identify novel flavonoid-based therapies to treat pathological pain and inflammation.

Quercetin promotes the survival of granulocytic myeloid-derived suppressor cells via the ESR2/STAT3 signaling pathway

Quercetin is a natural product that has been shown to induce tumor apoptosis and necrosis through multiple mechanisms. Tumor-induced myeloid-derived suppressor cell (MDSC) expansion negatively regulates the immune response by inhibiting T cell function through signal transducer and activator of transcription 3 (STAT3) activation, thereby facilitating tumor escape from host immune surveillance. Thus MDSC is an attractive target for cancer immunotherapy to enhance cytotoxic T cell responses. However, the effects of quercetin on MDSC are poorly understood. Here, we demonstrate that quercetin treatment enhanced mouse- and human- derived granulocytic-myeloid-derived suppressor cells (G-MDSC) survival and promoted the secretion of T cell-suppressive factors in vitro. Bioinformatics analysis further showed that quercetin was highly correlated with the estrogen receptor signaling pathway, which was confirmed by quantitative reverse transcription-polymerase chain reaction and flow cytometric analysis. These findings highlight the potential advantages and feasibility of quercetin in reinforcing the suppressive property of G-MDSC. Thus impact of G-MDSC should be taken into consideration when quercetin is applied to tumor therapy.

Review of the health effects of berries and their phytochemicals on the digestive and immune systems

Berries are generally considered beneficial to health. This health-promoting potential has mainly been ascribed to berries' phytochemical and vitamin content, and little attention has been paid to the potential benefits of berries for the digestive tract, despite this being the first point of contact. In vivo studies that described the health effects of berries on individual parts of the digestive tract (ie, the mouth, esophagus, stomach, small and large intestine, microbiome, and immune system) were reviewed. Immune effects were included because a large part of the immune system is located in the intestine. Beneficial health effects were mainly observed for whole berry extracts, not individual berry components. These effects ranged from support of the immune system and beneficial microbiota to reduction in the number and size of premalignant and malignant lesions. These results demonstrate the potency of berries and suggest berries can serve as a strong adjuvant to established treatments or therapies for a variety of gastrointestinal and immune-related illnesses.

Genome-wide localization of the polyphenol quercetin in human monocytes

BACKGROUND

Quercetin is a polyphenol of great interest given its antioxidant activity and involvement in the immune response. Although quercetin has been well studied at the molecular level as a gene regulator and an activator of specific cellular pathways, not much attention has been given to its mechanism of action at the genome-wide level. The present study aims to characterize quercetin's interaction with cellular DNA and to show its subsequent effect on downstream transcription.

RESULTS

Two massive parallel DNA-sequencing technologies were used: Chem-seq and RNA-seq. We demonstrate that upon binding to DNA or genome-associated proteins, quercetin acts as a cis-regulatory transcription factor for the expression of genes that are involved in the cell cycle, differentiation and development.

CONCLUSIONS

Such findings could provide new and important insights into the mechanisms by which the dietary polyphenol quercetin influences cellular functions.

Review and Meta-Analyses of TAAR1 Expression in the Immune System and Cancers

Since its discovery in 2001, the major focus of TAAR1 research has been on its role in monoaminergic regulation, drug-induced reward and psychiatric conditions. More recently, TAAR1 expression and functionality in immune system regulation and immune cell activation has become a topic of emerging interest. Here, we review the immunologically-relevant TAAR1 literature and incorporate open-source expression and cancer survival data meta-analyses. We provide strong evidence for TAAR1 expression in the immune system and cancers revealed through NCBI GEO datamining and discuss its regulation in a spectrum of immune cell types as well as in numerous cancers. We discuss connections and logical directions for further study of TAAR1 in immunological function, and its potential role as a mediator or modulator of immune dysregulation, immunological effects of psychostimulant drugs of abuse, and cancer progression.

Statistical analysis of human microarray data shows that dietary intervention with n-3 fatty acids, flavonoids and resveratrol enriches for immune response and disease pathways

n-3 Fatty acids, flavonoids and resveratrol are well publicised for their beneficial effects on human health and wellbeing. Identifying common, underlying biological mechanisms targeted by these functional foods would therefore be informative for the public health sector for advising on nutritional health and disease, food and drug product development and consumer interest. The aim of this study was to explore the potential effects of gene expression changes associated with n-3 fatty acids EPA and DHA, flavonoids and resveratrol on modifying biological systems and disease pathways. To test this, publicly available human microarray data for significant gene expression changes associated with dietary intervention with EPA/DHA, flavonoids and resveratrol was subjected to pathway analysis and significance testing for overlap with signals from genome-wide association studies (GWAS) for common non-communicable diseases and biological functions. There was an enrichment of genes implicated in immune responses and disease pathways which was common to all of the treatment conditions tested. Analysis of biological functions and disease pathways indicated anti-tumorigenic properties for EPA/DHA. In line with this, significance testing of the intersection of genes associated with these functional foods and GWAS hits for common biological functions (ageing and cognition) and non-communicable diseases (breast cancer, CVD, diabesity, neurodegeneration and psychiatric disorders) identified significant overlap between the EPA/DHA and breast cancer gene sets. Dietary intervention with EPA/DHA, flavonoids and resveratrol can target important biological and disease pathways suggesting a potentially important role for these bioactive compounds in the prevention and treatment of dietary-related diseases.

An update on the role of nutrigenomic modulations in mediating the cardiovascular protective effect of fruit polyphenols

Polyphenols are plant food microconstituents that are widely distributed in the human diet, with fruits and fruit-derived products as one of the main dietary sources. Epidemiological studies have shown an inverse relationship between the intake of different classes of polyphenols and the risk of myocardial infarction or cardiovascular disease (CVD) mortality. These compounds have been associated with the promotion of cardiovascular health as evidenced by clinical studies reporting beneficial effects of polyphenol-rich fruit consumption on intermediate markers of cardiovascular diseases. Additionally, animal and in vitro studies have indicated positive roles of polyphenols in preventing dysfunctions associated with the development of cardiovascular diseases. However, the mechanisms of action underlying their beneficial effects appear complex and are not fully understood. This review aims to provide an update on the nutrigenomic effects of different groups of polyphenols from fruits and especially focuses on their cardiovascular protective effects in cell and animal studies.

A compendium of monocyte transcriptome datasets to foster biomedical knowledge discovery

Systems-scale profiling approaches have become widely used in translational research settings. The resulting accumulation of large-scale datasets in public repositories represents a critical opportunity to promote insight and foster knowledge discovery. However, resources that can serve as an interface between biomedical researchers and such vast and heterogeneous dataset collections are needed in order to fulfill this potential. Recently, we have developed an interactive data browsing and visualization web application, the Gene Expression Browser (GXB). This tool can be used to overlay deep molecular phenotyping data with rich contextual information about analytes, samples and studies along with ancillary clinical or immunological profiling data. In this note, we describe a curated compendium of 93 public datasets generated in the context of human monocyte immunological studies, representing a total of 4,516 transcriptome profiles. Datasets were uploaded to an instance of GXB along with study description and sample annotations. Study samples were arranged in different groups. Ranked gene lists were generated based on relevant group comparisons. This resource is publicly available online at http://monocyte.gxbsidra.org/dm3/landing.gsp.

A curated compendium of monocyte transcriptome datasets of relevance to human monocyte immunobiology research

Systems-scale profiling approaches have become widely used in translational research settings. The resulting accumulation of large-scale datasets in public repositories represents a critical opportunity to promote insight and foster knowledge discovery. However, resources that can serve as an interface between biomedical researchers and such vast and heterogeneous dataset collections are needed in order to fulfill this potential. Recently, we have developed an interactive data browsing and visualization web application, the Gene Expression Browser (GXB). This tool can be used to overlay deep molecular phenotyping data with rich contextual information about analytes, samples and studies along with ancillary clinical or immunological profiling data. In this note, we describe a curated compendium of 93 public datasets generated in the context of human monocyte immunological studies, representing a total of 4,516 transcriptome profiles. Datasets were uploaded to an instance of GXB along with study description and sample annotations. Study samples were arranged in different groups. Ranked gene lists were generated based on relevant group comparisons. This resource is publicly available online at http://monocyte.gxbsidra.org/dm3/landing.gsp.

Higher plasma quercetin levels following oral administration of an onion skin extract compared with pure quercetin dihydrate in humans

PURPOSE

To investigate the plasma kinetics of quercetin derived from hard capsules filled with onion skin extract powder or quercetin dihydrate in humans.

METHODS

In a randomized, single-blind, diet-controlled crossover study, 12 healthy subjects (six men and six women) aged 21-33 years were administered a single oral supra-nutritional dose of approximately 163 mg quercetin derived from onion skin extract powder (containing 95.3 % of total flavonoids as quercetin aglycone) or quercetin dihydrate (134 mg quercetin aglycone equivalent). Blood samples were collected before and during a 24-h period after quercetin administration. The concentrations of quercetin and its two monomethylated derivatives, isorhamnetin (3'-O-methyl quercetin), and tamarixetin (4'-O-methyl quercetin), were measured using HPLC with fluorescence detection after plasma enzymatic treatment.

RESULTS

The systemic availability, determined by comparing the plasma concentration-time curves of quercetin, was 4.8 times higher, and the maximum plasma concentration (C _max) was 5.4 times higher after ingestion of the onion skin extract than after ingestion of pure quercetin dihydrate. By contrast, t _max did not differ significantly between the two formulations. The C _max values for isorhamnetin and tamarixetin were 3.8 and 4.4 times higher, respectively, after administration of onion skin extract than after pure quercetin dihydrate. The plasma kinetics of quercetin were not significantly different in men and women.

CONCLUSION

Quercetin aglycone derived from onion skin extract powder is significantly more bioavailable than that from quercetin dihydrate powder filled hard capsules.

Whole-Blood Gene Expression Profiles in Large-Scale Epidemiological Studies: What Do They Tell?

In nutrigenomics, gene expression profiling is used to investigate transcriptional mechanisms associated with nutrients and diet. Blood samples collected in the framework of dietary interventions and epidemiological studies allow the use of humans as the model system, as opposed to using cell lines or animal models. Here, we review recent publications in the field of gene expression profiling, based on a systematic literature search focusing on studies from the last 5 years and including studies that investigated either single nutrients, foods, food groups, or dietary patterns. Findings highlight the role of inflammatory processes as key mediators of the association between diet and disease and point to the relevance of using blood as the target tissue in nutrigenomics. However, recurring challenges include study design issues, practical and statistical challenges, and biological interpretation of the results. Many of the published studies have small sample size, and given the nature of gene expression data, their conclusions have limited impact. These challenges should be addressed by future nutrigenomics studies in order to increase their relevance and validity.

HDGF: a novel jack-of-all-trades in cancer

HDGF is an important regulator of a broad range of cancer cell activities and plays important roles in cancer cell transformation, apoptosis, angiogenesis and metastasis. Such a divergent influence of HDGF on cancer cell activities derives from its multiple inter- and sub-cellular localizations where it interacts with a range of different binding partners. Interestingly, high levels of HDGF could be detected in patients' serum of some cancers. This review is focused on the role of HDGF in tumorigenesis and metastasis, and provides insight for application in clinical cancer therapy as well as its clinical implications as a prognostic marker in cancer progression.

Effects of flavonoid quercetin on survival of motor neuron gene expression

Spinal muscular atrophy (SMA) is a progressive neurodegenerative disease that results in muscle weakness and atrophy. To attenuate disease severity, drug development studies have been applied mainly to target the Survival of Motor Neuron 2 (SMN2) gene, which is an important modifier of SMA. Although several compounds have been tested, there is still no cure for SMA. In this study, SMN2-inducing effects of quercetin, an abundant flavonoid polyphenol in human diet, was investigated in the fibroblast cell lines of two SMA type I patients. Gene expression studies showed that quercetin upregulates SMN2 mRNA up to fourfold, but not the SMN protein level.

Isoflavone supplement composition and equol producer status affect gene expression in adipose tissue: a double-blind, randomized, placebo-controlled crossover trial in postmenopausal women

BACKGROUND

Isoflavone supplements, consumed by women experiencing menopausal symptoms, are suggested to have positive effects on menopause-related adiposity and cardiovascular disease risk profile, but discussions about their safety are still ongoing.

OBJECTIVE

The objective was to study the effects of an 8-wk consumption of 2 different isoflavone supplements compared with placebo on whole-genome gene expression in the adipose tissue of postmenopausal women.

DESIGN

This double-blind, randomized, placebo-controlled crossover intervention consisted of 2 substudies, one with a low-genistein (LG) supplement (56% daidzein + daidzin, 16% genistein + genistin, and 28% glycitein + glycitin) and the other with a high-genistein (HG) supplement (49% daidzein + daidzin, 41% genistein + genistin, and 10% glycitein + glycitin). Both supplements provided ∼ 100 mg isoflavones/d (aglycone equivalents). After the 8-wk isoflavone and placebo period, whole-genome arrays were performed in subcutaneous adipose tissue of postmenopausal women (n = 26 after LG, n = 31 after HG). Participants were randomized by equol-producing phenotype, and data analysis was performed per substudy for equol producers and nonproducers separately.

RESULTS

Gene set enrichment analysis showed downregulation of expression of energy metabolism-related genes after LG supplementation (n = 24) in both equol-producing phenotypes and oppositely regulated expression for equol producers (down) and nonproducers (up) after HG supplementation (n = 31). Expression of inflammation-related genes was upregulated in equol producers but downregulated in nonproducers, independent of supplement type. Only 4.4-7.0% of the genes with significantly changed expression were estrogen responsive. Body weight, adipocyte size, and plasma lipid profile were not affected by isoflavone supplementation.

CONCLUSIONS

Effects of isoflavones on adipose tissue gene expression were influenced by supplement composition and equol-producing phenotype, whereas estrogen-responsive effects were lacking. LG isoflavone supplementation resulted in a caloric restriction-like gene expression profile for both producer phenotypes and pointed toward a potential beneficial effect, whereas both supplements induced anti-inflammatory gene expression in equol producers. The study was registered at clinicaltrials.gov as NCT01556737.

Dietary flavanols modulate the transcription of genes associated with cardiovascular pathology without changes in their DNA methylation state

Background

In a recent intervention study, the daily supplementation with 200 mg monomeric and oligomeric flavanols (MOF) from grape seeds for 8 weeks revealed a vascular health benefit in male smokers. The objective of the present study was to determine the impact of MOF consumption on the gene expression profile of leukocytes and to assess changes in DNA methylation.

Methodology/Principal Findings

Gene expression profiles were determined using whole genome microarrays (Agilent) and DNA methylation was assessed using HumanMethylation450 BeadChips (Illumina). MOF significantly modulated the expression of 864 genes. The majority of the affected genes are involved in chemotaxis, cell adhesion, cell infiltration or cytoskeleton organisation, suggesting lower immune cell adhesion to endothelial cells. This was corroborated by in vitro experiments showing that MOF exposure of monocytes attenuates their adhesion to TNF-α-stimulated endothelial cells. Nuclear factor kappa B (NF-κB) reporter gene assays confirmed that MOF decrease the activity of NF-κB. Strong inter-individual variability in the leukocytes' DNA methylation was observed. As a consequence, on group level, changes due to MOF supplementation could not be found.

Conclusion

Our study revealed that an 8 week daily supplementation with 200 mg MOF modulates the expression of genes associated with cardiovascular disease pathways without major changes of their DNA methylation state. However, strong inter-individual variation in leukocyte DNA methylation may obscure the subtle epigenetic response to dietary flavanols. Despite the lack of significant changes in DNA methylation, the modulation of gene expression appears to contribute to the observed vascular health effect of MOF in humans.

Nutri-informatics: a new kid on the block?

From an epistemological point of view, nutritional physiology has been developed, like other factual sciences such as physics, from a purely descriptive to a mechanismic-explanatory scientific discipline. Nowadays, nutritional physiology has entered the molecular stage. Based on this micro-reductionism, molecular targets (e.g., transcription factors) of energy intake, certain nutrients (e.g., zinc) and selected plant bioactives (e.g., flavonoids) have been identified. Although these results are impressive, molecular approaches in nutritional physiology are limited by nature since the molecular targets of nutrients seem to have no ontic priority to understand the nutritional phenotype of an organism. Here we define, to the best of our knowledge, for the first time Nutri-informatics as a new bioinformatics discipline integrating large-scale data sets from nutritional studies into a stringent nutritional systems biology context. We suggest that Nutri-informatics, as an emerging field, may bridge the gap between nutritional biochemistry, nutritional physiology and metabolism to understand the interactions between an organism and its environment.

Nutritional aspects of metabolic inflammation in relation to health--insights from transcriptomic biomarkers in PBMC of fatty acids and polyphenols

Recent research has highlighted potential important interaction between metabolism and inflammation, within the context of metabolic health and nutrition, with a view to preventing diet-related disease. In addition to this, there is a paucity of evidence in relation to accurate biomarkers that are capable of reflecting this important biological interplay or relationship between metabolism and inflammation, particularly in relation to diet and health. Therefore the objective of this review is to highlight the potential role of transcriptomic approaches as a tool to capture the mechanistic basis of metabolic inflammation. Within this context, this review has focused on the potential of peripheral blood mononuclear cells transcriptomic biomarkers, because they are an accessible tissue that may reflect metabolism and subacute chronic inflammation. Also these pathways are often dysregulated in the common diet-related diseases obesity, type 2 diabetes, and cardiovascular disease, thus may be used as markers of systemic health. The review focuses on fatty acids and polyphenols, two classes of nutrients/nonnutrient food components that modulate metabolism/inflammation, which we have used as an example of a proof-of-concept with a view to understanding the extent to which transcriptomic biomarkers are related to nutritional status and/or sensitive to dietary interventions. We show that both nutritional components modulate inflammatory markers at the transcriptomic level with the capability of profiling pro- and anti-inflammatory mechanisms in a bidirectional fashion; to this end transcriptomic biomarkers may have potential within the context of metabolic inflammation. This transcriptomic biomarker approach may be a sensitive indicator of nutritional status and metabolic health.

Hesperidin displays relevant role in the nutrigenomic effect of orange juice on blood leukocytes in human volunteers: a randomized controlled cross-over study

Background

We previously showed, in healthy, middle-aged, moderately overweight men, that orange juice decreases diastolic blood pressure and significantly improves postprandial microvascular endothelial reactivity and that hesperidin could be causally linked to the observed beneficial effect of orange juice. The objective was to determine the effect of chronic consumption of orange juice on the gene expression profile of leukocytes in healthy volunteers and to assess to what extent hesperidin is involved in the effect of orange juice.

Methodology/Principal Findings

Volunteers were included in a randomized, controlled, crossover study. Throughout three 4-week periods, volunteers consumed daily: 500 ml orange juice, 500 ml control drink plus hesperidin or 500 ml control drink and placebo. Blood samplings were performed on 10 overnight-fasted subjects after the 4-week treatment period. Global gene expression profiles were determined using human whole genome cDNA microarrays. Both orange juice and hesperidin consumption significantly affected leukocyte gene expression. Orange juice consumption induced changes in expression of, 3,422 genes, while hesperidin intake modulated the expression of 1,819 genes. Between the orange juice and hesperidin consumption groups, 1,582 regulated genes were in common. Many of these genes are implicated in chemotaxis, adhesion, infiltration and lipid transport, which is suggestive of lower recruitment and infiltration of circulating cells to vascular wall and lower lipid accumulation.

Conclusions

This study shows that regular consumption of orange juice for 4 weeks alters leukocyte gene expression to an anti-inflammatory and anti-atherogenic profile, and hesperidin displays a relevant role in the genomic effect of this beverage.

Trial Registration

ClinicalTrials.gov NCT 00983086

Regulation of the hematopoietic cell kinase (HCK) by PML/RARα and PU.1 in acute promyelocytic leukemia

This study investigates the dynamic regulation of human hematopoietic cell kinase (HCK) in acute promyelocytic leukemia (APL) and the underlying molecular mechanisms. First, the level of HCK in APL blasts was found lower than that in normal granulocytes and monocytes. Second, the HCK promoter was repressed by PML/RARα and this repression required PU.1. PU.1 was capable of transactivating the HCK promoter through a region encompassing three PU.1 motifs. Chromatin immunoprecipitation assays provided evidence that PU.1 and PML/RARα bound to the HCK promoter in vivo. Finally, we found an unequivocal increase of HCK expression upon treatment with all-trans retinoic acid.

Quercetin accumulates in nuclear structures and triggers specific gene expression in epithelial cells

Quercetin is a flavonol modifying a number of cell processes in different cell lines. Here, we present evidence that nonconjugated quercetin enters cells possibly via organic anion transporter polypeptides and quickly accumulates in the nucleus where it concentrates at distinct foci. Furthermore, it induces major transcriptional events with a high number of transcripts being modified over time and about 2200 transcripts being continuously influenced by the agent. The latter transcripts are related to cell cycle and adhesion, xenobiotic metabolism, immune-related factors and transcription. In addition, quercetin up-regulates the expression of estrogen receptors α and β. The overall outcome on cell fate is reflected by an inhibition of cell proliferation, cell cycle arrest in the G1 phase and reduction of the cells' migratory potential due to actin cytoskeleton disorganization. Finally, we report that the flavonol modifies the transcription and/or activity of numerous transcription factors. In conclusion, our data support the idea that quercetin may actively accumulate in discrete cell structures and exert more than just antioxidant actions on epithelial cells by regulating mechanisms related to gene transcription.