Concomitant use of tea catechins affects absorption and serum triglyceride-lowering effects of monoglucosyl hesperidin.

The present study investigated whether combined ingestion of green tea catechins (GTC) and monoglucosyl hesperidin (GHES) influences the pharmacokinetic parameters of polyphenols and serum triglycerides (TG). We conducted 2 randomized, controlled trials. Study 1: 8 healthy male subjects participated in a crossover study in which they ingested a test beverage containing GHES (0, 84, 168, or 336 mg GHES) with GTC, or 336 mg GHES without GTC. After ingestion, the pharmacokinetic changes in plasma hesperetin (HEP) and catechins were measured. Study 2: 36 healthy male and female subjects (mean age, 53 ± 2 years; mean BMI, 25.2 ± 0.5 kg m-2) were recruited for a double-blind, placebo-controlled study in which they ingested a test beverage containing 165 mg GHES with 387 mg GTC or a placebo beverage daily for 4 weeks. Fasting serum TG and other lipids and glucose metabolites were analyzed. Study 1 showed that the pharmacokinetics of HEP did not differ significantly between the 336 mg GHES without GTC treatment and the 168 mg GHES with GTC treatment. Study 2 showed that continuous ingestion of 165 mg GHES and 387 mg GTC for 4 weeks significantly decreased fasting serum TG levels compared with baseline values (change in TG, -30 ± 13 mg dl-1, P = 0.040) in the intention-to-treat analysis. In conclusion, our findings suggest that GTC affects the oral bioavailability of GHES, and combined ingestion of low doses of GHES with GTC effectively improves fasting TG levels.

Effects of Hesperidin Consumption on the Cardiovascular System in Pre- and Stage 1 Hypertensive Subjects: Targeted and Non-Targeted Metabolomic Approaches (CITRUS Study).

SCOPE: The aim of the present work is to determine new biomarkers of the biological effects of hesperidin in orange juice (OJ) applying a non-targeted metabolomics approach validated by targeted metabolomics analyses of compliance biomarkers. METHODS AND RESULTS: Plasma/serum and urine targeted (HPLC-MS/MS) and untargeted (1 H-NMR) metabolomics signatures are explored in a subsample with pre- and stage-1 hypertension subjects of the CITRUS study (N = 159). Volunteers received 500 mL day-1 of control drink, OJ, or hesperidin-enriched OJ (EOJ) for 12-weeks. A 6-h postprandrial study is performed at baseline. Targeted analyses reveals plasma and urine hesperetin 7-O-ß-d-glucuronide as the only metabolite differing between OJ and EOJ groups after 12-weeks consumption, and in urine is correlated with a decreased systolic blood pressure level. The non-targeted approach shows that after single dose and 12-weeks consumption of OJ and EOJ change several metabolites related with an anti-inflammatory and antioxidant actions, lower blood pressure levels and uremic toxins. CONCLUSIONS: Hesperetin 7-O-ß-d-glucuronide can be a candidate marker for distinguishing between the consumption of different hesperidin doses at 12-weeks consumption as well as a potential agent mediating blood pressure reduction. Moreover, changes in different endogenous metabolites can explain the mechanisms of action and the biological effects of hesperidin consumption.

Dissection of the potential pharmacological function of neohesperidin dihydrochalcone - a food additive - by in vivo substances profiling and network pharmacology.

Food additives are widely used in our daily life, and the side-effects caused by them have gained extensive attention around the world. Notably, constituent-oriented metabolites, in some sense, always contribute to pharmacological changes, inducing toxicity, therapeutic effects, etc. Characterization of the metabolites and their potential functions is of great importance to the practical applications. In this work, an integrated strategy by combining metabolite profiling and network pharmacology was applied to characterize the metabolic features and reveal pharmacological changes of neohesperidin dihydrochalcone (NHDC) in vivo to demonstrate its pharmacological mechanism and potential functions. As a result, a total of 19 metabolites (3 in plasma, 19 in urine, 8 in feces, 3 in heart, 5 in liver, 0 in spleen, 1 in lung, 2 in kidneys and 2 in brain) were screened and 18 of them were characterized for the first time. Phase I metabolic reactions of hydrolysis and phase II reactions of glucuronidation, sulfation, glutamylation, N-butyryl glycylation and lactylation were the main metabolic reactions of NHDC in vivo. Moreover, the results analyzed by network pharmacology revealed that, in addition to common pathways (steroid hormone biosynthesis) of NHDC, metabolites' targets were involved in pathways in cancer, ovarian steroidogenesis, proteoglycans in cancer, PI3K-Akt signaling pathway and progesterone-mediated oocyte maturation, indicating that these functional changes might result in potential novel functions or other side-effects, such as a disorder of steroid hormones. Our work provided the metabolic features and functional modifications of NHDC in vivo for the first time, and meaningful information for further pharmacological validations or potential functions is supplied.

Discovery and validation of quality markers of Fructus Aurantii against acetylcholinesterase using metabolomics and bioactivity assays.

Fructus Aurantii is a traditional medicated diet in East Asia. To determine the underlying chemical markers responsible for the quality and efficacy of Fructus Aurantii, a sensitive metabolomic method was applied to distinguish Fructus Aurantii in Jiangxi Province from other two geographical locations (Hunan Province and Chongqing City) in China. In the present study, multivariate analyses were adopted to compare chemical compositions in 21 batches of Fructus Aurantii samples. Among three geographical origins, 23 differential compounds were structurally identified. Serum pharmacochemistry exhibited that 22 components could be detected in rat serum. Six differential and absorbed components were selected as six potential markers. Statistical analysis revealed that the content of six markers varied widely in three origins of Fructus Aurantii. Six differential and absorbed components were evaluated further by biological activity. Neohesperidin, naringin, and meranzin showed inhibitory effect on acetylcholinesterase that regulates gastrointestinal motility in vitro and in silico, suggesting that these three components may be determined as the active biomarkers of Fructus Aurantii. These findings demonstrate the potential of biomarkers for identification and quality control of Fructus Aurantii.

Development and Optimization of a High Sensitivity LC-MS/MS Method for the Determination of Hesperidin and Naringenin in Rat Plasma: Pharmacokinetic Approach.

The purpose of this study was to develop, optimize, and fully validate a high-sensitivity methodology using UHPLC-MS/MS to simultaneously quantify hesperidin and naringenin in microsamples (100 µL) of murine plasma after intragastric administration of single pure flavonoids and a mixture. The optimization process allowed for high sensitivity with detection limits of approximately picogram order using an electrospray ionization (ESI) source in negative mode and an experiment based on multiple reaction monitoring (MRM). The validation parameters showed excellent linearity and detection limits, with a precision of less than 8% and a recovery of over 90%. This methodology was applied to compare the pharmacokinetic parameters for the administration of hesperidin and naringenin in individual form or in the form of a mixture. The results showed an absence of significant effects (p > 0.05) for Tmax and Cmax; however, the AUC presented significant differences (p < 0.05) for both flavonoids when administered as a mixture, showing an improved absorption ratio for both flavonoids.

Absorption and Metabolic Behavior of Hesperidin (Rutinosylated Hesperetin) after Single Oral Administration to Sprague-Dawley Rats.

We investigated the absorption and metabolic behavior of hesperidin (hesperetin-7-O-rutinoside) in the blood system of Sprague-Dawley rats by liquid chromatography- and matrix-assisted laser desorption ionization mass spectrometries (LC-MS and MALDI-MS). After a single oral administration of hesperidin (10 mg/kg), which was expected to be absorbed in its degraded hesperetin form, we detected intact hesperidin in the portal vein blood (tmax, 2 h) for the first time. We successfully detected glucuronized hesperidin in the circulating bloodstream, while intact hesperidin had disappeared. Further MS analyses revealed that homoeriodictyol and eriodictyol conjugates were detected in both portal and circulating blood systems. This indicated that hesperidin and/or hesperetin are susceptible to methylation and demethylation during the intestinal membrane transport process. Sulfated and glucuronized metabolites were also detected in both blood systems. In conclusion, hesperidin can enter into the circulating bloodstream in its conjugated forms, together with the conjugated forms of hesperetin, homoeriodictyol, and/or eriodictyol.

Comparative pharmacokinetic study of four major bioactive components after oral administration of Zhi-Zi-Hou-Po decoction in normal and corticosterone-induced depressive rats.

A highly selective and efficient LC-MS/MS method was developed to determine the plasma concentration of magnolol, hesperidin, neohesperidin and geniposide following oral administration of Zhi-Zi-Hou-Po decoction in normal and depressed rats. Plasma samples were pretreated by protein precipitation with methanol. Chromatographic separation was performed on an XTerra® MS C18 column using a gradient elution with a mobile phase composed of acetonitrile-0.1% aqueous formic acid. The proposed method was validated to be specific, accurate and precise for the analytes determination in plasma samples. The calibration curves displayed good linearity over definite concentration ranges for the analytes. The intra- and inter-day precision of the proposed method at three different levels were all within <11.13% and the relative errors ranged from -8.46 to 8.93%. The recovery of the four compounds ranged from 82.72 to 89.08% and no apparent matrix effect was observed during sample analysis. After full validation, the established method was successfully applied for comparing the pharmacokinetics of four components between normal and depressed rats. The results showed that the AUC and Cmax of four analytes in depressed rats were significantly different from those in normal rats and might provide helpful information to guide the clinical use of Zhi-Zi-Hou-Po to treat depression.

Simultaneous Determination and Quantitation of Diosmetin and Hesperetin in Human Plasma by Liquid Chromatographic Mass Spectrometry With an Application to Pharmacokinetic Studies.

Among the secondary metabolites which are widely distributed in plants and foods in plant origin flavonoids is important one. Flavonoids have antioxidant activities as free radical scavenging action. They also have anti-inflammatory, antiulcer and anti-carcinogenic activities. Diosmin and hesperidin, the metabolites of which are diosmetin and hesperitin respectively are considered in the present study. Diosmetin has anticancer, antioxidant and blood lipid lowering activities. It also enhances venous tone and microcirculation and by reducing systemic oxidative stress it protects capillaries. Hesperitin also has antioxidant, anti-inflammatory, blood lipid and cholesterol lowering, anti-carcinogenic activities. In the present study efforts were given to develop and validate a bioanalytical method for simultaneous estimation of diosmetin and hesperitin in human plasma by liquid chromatography electron spray ionization mass spectrometry with an application to the analysis of plasma samples obtained from the comparative pharmacokinetic studies on healthy human volunteers under the framework of bioequivalence study. The developed method for simultaneous determination and quantification of diosmetin and hesperitin in human plasma was validated as per the US-FDA guidelines. The validation parameters found within the specified regulatory limit, hence acceptable. The present method also has a short run time (6.0 min) and easy extraction process. The developed method was found to be simple, specific, highly selective, sensitive and reproducible. This was applied for the analysis of the volunteer plasma samples. On the basis of comparison of the AUC0-t, the relative bioavailability of the test preparation was found 100.94 and 95.09% for diosmetin and hesperitin respectively of that of the reference preparation.

Pharmacokinetic study of the prokinetic ABCs liquiritigenin, naringenin and hesperitin following the oral administration of Si-Ni-San decoction to functional dyspepsia patients.

1. The pharmacokinetics (PKs) analysis of compounds absorbed after the oral administration of Si-Ni-San (SNS) decoction to functional dyspepsia (FD) patients was designed to detect whether the effects were similar to prokinetics administered to healthy rats, without ethical limitation. 2. First, the absorbed compounds, liquiritigenin (L), naringenin (N) and hesperitin (H) in the plasma were identified by UPLC-MS/MS following the oral administration of SNS decoction to subjects with FD. Next, the natural ratio of LNH in the SNS decoction was determined by UPLC. Third, gastric emptying and intestinal transit after the oral administration of LNH, in combination or alone, was compared with those observed after SNS administration in healthy rats. Additionally, the clinical PKs of LNH was studied. 3. The prokinetic efficacy of LNH administered at their natural ratios (7.5:5:1) increased dose-dependently and was better than the observed efficacy when administered alone in rats. Analysis of the clinical PK parameters, calculated using a one-compartment model, showed that the Cmax parameters of LNH in 3, 4 and 4 h were 639.17, 410.00 and 181.67 µg/L, respectively. 4. The clinical herbal PK analysis of the absorbed LNH preclinical prokinetic compounds, in their natural ratio from SNS, highlights the impact of an herbal translational pharmacology study.

A Critical Evaluation of In Vitro Hesperidin 2S Bioavailability in a Model Combining Luminal (Microbial) Digestion and Caco-2 Cell Absorption in Comparison to a Randomized Controlled Human Trial.

SCOPE: Bioavailability strongly determines polyphenol bioactivity, and is strongly influenced by food matrix, enzymatic and microbial degradation, and gastrointestinal absorption. To avoid human trials for pre-screening of polyphenol bioavailability, studies have focused on in vitro model development. Nevertheless, their predictive value for bioavailability can be questioned. METHOD AND RESULTS: We used the orange flavonoid hesperidin 2S to validate a model combining digestion in the simulator of the human intestinal microbial ecosystem (SHIME) and Caco-2 cell transport, with a human intervention study. In vitro, hesperidin was resistant to degradation in the stomach and small intestine, but was rapidly deconjugated on reaching the proximal colon. Extensive and colon-region-specific degradation to smaller phenolics was observed. Hydrocaffeic and dihydroisoferulic acid accumulated in proximal, and hydroferulic acid in distal colon. Caco-2 transport was the highest for dihydroisoferulic acid. In humans, plasma and urine hesperetin-glucuronide levels increased significantly, whereas the impact on small phenolics was limited. CONCLUSIONS: In the combined in vitro model, smaller phenolics strongly accumulated, whereas in humans, hesperetin conjugates were the main bioavailable compounds. Future in vitro model development should focus on simulating faster polyphenol absorption and elimination of smaller phenolics to improve their predictive value of in vivo polyphenol bioavailability.

Physiologically based kinetic modeling of hesperidin metabolism and its use to predict in vivo effective doses in humans.

SCOPE: To develop a physiologically based kinetic (PBK) model that describes the absorption, distribution, metabolism, and excretion of hesperidin in humans, enabling the translation of in vitro concentration-response curves to in vivo dose-response curves. METHODS AND RESULTS: The PBK model for hesperidin in humans was developed based on in vitro metabolic parameters. Hesperidin was predicted to mainly occur in the systemic circulation as different monoglucuronides. The plasma concentrations of hesperidin aglycone (hesperetin) was predicted to be <0.02 mg/L at an oral dose of 50 mg/kg bw. The developed PBK model allowed conversion of in vitro concentration-response curves for different effects to in vivo dose-response curves. The BMD05 (benchmark dose for 5% response) values for protein kinase A inhibition ranged between 135 and 529 mg/kg bw hesperidin, and for inhibition of endothelial cell migration and prostaglandin E2 and nitric oxide production ranged between 2.19 and 44 mg/kg bw hesperidin. These values are in line with reported human data showing in vivo effects by hesperidin and show that these effects may occur at Western dietary and supplementary intake of hesperidin. CONCLUSIONS: The developed PBK model adequately predicts absorption, distribution, metabolism, and excretion of hesperidin in humans and allows to evaluate the human in vivo situation without the need for human intervention studies.

A HPLC-MS/MS method for the quantitation of free, conjugated, and total HDND-7, a novel hesperetin derivative, in rat plasma and tissues: Application to the pharmacokinetic and tissue distribution study.

A sensitive and reliable HPLC-MS/MS method was developed and validated for the determination of free (unconjugated), glucuronidated, sulfated, and total (free and conjugated) HDND-7 in rat plasma and tissues. Plasma and tissues samples were treated prior to and after the enzyme hydrolysis. Chromatographic separation was achieved on a Phenomenex Luna C18 column (150 × 4.6mm, 3 µm), using isocratic mobile phase consisting of 0.1% formic acid-acetonitrile (50:50, v/v) at a flow rate of 300 µl/min. The detection was performed on a triple quadruple tandem mass spectrometer using positive electrospray ionization (ESI) source with a chromatographic run time of 5.0 min. The detection was operated by multiple reaction monitoring (MRM) of the transitions of m/z 429.3 → 223.9 for HDND-7 and 272.9 → 152.9 for naringenin (IS), respectively. This method was validated in terms of specificity, linearity, precision, accuracy, and stability. The calibration curves for plasma and tissues were linear over a wide concentration range of 0.02-40 µg/ml with a lower limit of quantification (LLOQ) of 0.02 µg/ml. Mean extraction recoveries in plasma and tissues ranged from 87.4 to 97.1% and from 54.2 to 70.5%, respectively. The intra- and inter-day precision values were below 15% and the accuracy was within ± 15%. The samples were stable under all the tested conditions. This method has been successfully applied to the pharmacokinetic study following oral doses of 25, 50 and 100mg/kg and intravenous dose of 25mg/kg, and tissue distribution study following oral dose of 50mg/kg.

Gastrointestinal absorption and metabolism of hesperetin-7-O-rutinoside and hesperetin-7-O-glucoside in healthy humans.

SCOPE: Hesperetin-7-O-rutinoside (hesperidin) reduces blood pressure in healthy volunteers but its intestinal absorption and metabolism are not fully understood. Therefore, we aimed to determine sites of absorption and metabolism of dietary flavanone glycosides in humans. METHODS AND RESULTS: Using a single-blind, randomized crossover design, we perfused equimolar amounts of hesperetin-7-O-rutinoside and hesperetin-7-O-glucoside directly into the proximal jejunum of healthy volunteers. We assessed the appearance of metabolites in the perfusate, blood and urine, to determine the sites of metabolism and excretion, and compared this to oral administration. The glucoside was rapidly hydrolyzed by brush border enzymes without any contribution from pancreatic, stomach, or other secreted enzymes, or from bacterial enzymes. Only ∼3% of the dose was recovered intact in the perfusate, indicating high absorption. A proportion was effluxed directly back into the perfused segment mainly in the form of hesperetin-3'-O-sulfate. In contrast, very little hydrolysis or absorption of hesperetin-7-O-rutinoside was observed with ∼80% recovered in the perfusate, no hesperetin metabolites were detected in blood and only traces were excreted in urine. CONCLUSION: The data elucidate the pathways of metabolism of dietary hesperidin in vivo and will facilitate better design of mechanistic studies both in vivo and in vitro.

Marked antioxidant effect of orange juice intake and its phytomicronutrients in a preliminary randomized cross-over trial on mild hypercholesterolemic men.

BACKGROUND & AIMS: Blond orange juice is the most consumed fruit juice in the world. It is a source of hesperidin, a bioavailable flavonoid reported to exhibit potential vascular protective actions. However, the specific impact on vascular function of Citrus phytomicronutrients, is unknown. For the first time, we investigated the effects of blond orange juice compared with a control beverage mimicking the composition of orange juice (including Vitamin C but no phytomicronutrients), on antioxidant markers, cardiovascular risk factors and endothelial function. METHODS: Twenty five male volunteers with two cardiovascular risk factors (age over 50 years and LDL-cholesterol between 130 and 190 mg/L) were enrolled in a randomized cross-over study. They received 3 times daily 200 mL of either blond orange juice or control beverage for 4 weeks, spaced by a 5-week wash-out. Endothelial function (flow mediated dilatation and plasma markers), oxidative status, lipid profile and inflammatory markers were assessed. RESULTS: Daily intakes of orange juice significantly led to a marked antioxidant effect which was correlated to hesperetin plasma levels and related with a decrease in reactive oxygen species. A tendency towards reduction of endothelial dysfunction and modest increase in plasma apoA-I concentration were also observed. This allows further experiments demonstrating the specific effect of phytomicronutrients from orange juice. CONCLUSIONS: These findings suggest that daily intake of nutritionally relevant dose of blond orange juice may contribute for a significant antioxidant effect through the phytochemicals contained in. Orange juice may be associated to other healthy foods to achieve a significant effect on the vascular function. This study is recorded in ClinicalTrials.com as NCT00539916.

Orange juice-derived flavanone and phenolic metabolites do not acutely affect cardiovascular risk biomarkers: a randomized, placebo-controlled, crossover trial in men at moderate risk of cardiovascular disease.

BACKGROUND: Epidemiologic data suggest inverse associations between citrus flavanone intake and cardiovascular disease (CVD) risk. However, insufficient randomized controlled trial data limit our understanding of the mechanisms by which flavanones and their metabolites potentially reduce cardiovascular risk factors. OBJECTIVE: We examined the effects of orange juice or a dose-matched hesperidin supplement on plasma concentrations of established and novel flavanone metabolites and their effects on cardiovascular risk biomarkers in men at moderate CVD risk. DESIGN: In an acute, randomized, placebo-controlled crossover trial, 16 fasted participants (aged 51-69 y) received orange juice or a hesperidin supplement (both providing 320 mg hesperidin) or control (all matched for sugar and vitamin C content). At baseline and 5 h postintake, endothelial function (primary outcome), blood pressure, arterial stiffness, cardiac autonomic function, platelet activation, and NADPH oxidase gene expression and plasma flavanone metabolites were assessed. Before each intervention, a diet low in flavonoids, nitrate/nitrite, alcohol, and caffeine was followed, and a standardized low-flavonoid evening meal was consumed. RESULTS: Orange juice intake significantly elevated mean ± SEM plasma concentrations of 8 flavanone (1.75 ± 0.35 µmol/L, P < 0.0001) and 15 phenolic (13.27 ± 2.22 µmol/L, P < 0.0001) metabolites compared with control at 5 h postconsumption. Despite increased plasma flavanone and phenolic metabolite concentrations, cardiovascular risk biomarkers were unaltered. After hesperidin supplement intake, flavanone metabolites were not different from the control, suggesting altered absorption/metabolism compared with the orange juice matrix. CONCLUSIONS: After single-dose flavanone intake within orange juice, circulating flavanone and phenolic metabolites collectively reached a concentration of 15.20 ± 2.15 µmol/L, but no effects were observed on cardiovascular risk biomarkers. Longer-duration randomized controlled trials are required to examine previous associations between higher flavanone intakes and improved cardiovascular health and to ascertain the relative importance of food matrix and flavanone-derived phenolic metabolites. This trial was registered at clinicaltrials.gov as NCT01530893.

Application of a liquid chromatography-tandem mass spectrometry method to the pharmacokinetics, bioavailability and tissue distribution of neohesperidin dihydrochalcone in rats.

1. This study was aimed at developing a high sensitive and selective liquid chromatography-tandem mass spectrometry method to quantify neohesperidin dihydrochalcone (NHDC) in rat plasma and tissues for pharmacokinetic, bioavailability and tissue distribution studies. 2. Biological samples were processed with one-step protein precipitation. Rutin was chosen as the internal standard (IS). Chromatographical separation was achieved on an SB-C18 (2.1 mm× 150 mm, 5 µm) column with acetonitrile--0.1% formic acid in water as the mobile phase with gradient elution. Electrospray ionization (ESI) source was applied and operated in negative ion mode; selected ion monitoring mode was used for quantification using target fragment ions m/z 611.4 for NHDC and m/z 609.1 for IS. 3. Calibration plots were linear over the range of 10-3000 ng/mL for NHDC. Lower limit of quantification (LLOQ) for NHDC was 10 ng/mL. Mean recovery of NHDC from plasma and tissues was better than 80.3%. Coefficient of variation of intra-day and inter-day precision were both less than 15%. The bioavailability of NHDC was 21.8%. 4. In conclusion, a sensitive, simple and specific LC-ESI-MS method for the determination of NHDC in rat biological samples was developed. This developed method is successfully used in the pharmacokinetic and tissue distribution study of NHDC in rats.

Simplified miniaturized ultrasound-assisted matrix solid phase dispersion extraction and high performance liquid chromatographic determination of seven flavonoids in citrus fruit juice and human fluid samples: hesperetin and naringenin as biomarkers.

In the present study, for the first time, a simplified miniaturized ultrasound-assisted matrix solid-phase dispersion (SM-USA-MSPD) method with a different application for liquid matrices was developed to extract different flavonoids (hesperidin, diosmin, eriocitrin, narirutin, naringin, hesperetin and naringenin) from citrus fruit juice and human fluid samples prior to their determination using high performance liquid chromatography (HPLC). Different effective parameters were studied and under the optimum conditions (including sample volume: 150µL; solid phase: silica-based C18, 200mg; eluting solvent: methanol, 500µL; pH: 4; and sonication: 6min; at room temperature), limits of detection and limits of quantification were ranged from 23.3 to 46.8ngmL(-1) and 74.8 to 141.5ngmL(-1), respectively. Once optimized, analytical performance of the method was studied in terms of linearity (0.074-198.5µgmL(-1), r(2)>0.991), accuracy (recovery=84.6-101.5%), and precision (repeatability: intra-day precision<5.9%, and inter-day precision<7.2%). At the end, SM-USA-MSPD method was successfully applied to estimate the levels of hesperetin and naringenin in plasma and urinary excretion -after ingestion of orange, grapefruit and lime juices- and the obtained results confirmed that these compounds could be used as good biomarkers of citrus fruit juice intake.

Hesperidin metabolite hesperetin-7-O-glucuronide, but not hesperetin-3'-O-glucuronide, exerts hypotensive, vasodilatory, and anti-inflammatory activities.

Orally ingested hesperidin (HES) is hydrolyzed into hesperetin in the gastrointestinal tract and conjugated during absorption. Hesperetin conjugates are the main circulating metabolites in human and rat plasma. We previously reported that glucosyl hesperidin (GHES), a water-soluble HES derivative, prevents hypertension via improvement of endothelial dysfunction in spontaneously hypertensive rats (SHRs). Although these hesperetin conjugates seem to be responsible for hypotensive and endothelium-dependent vasodilatory activities of dietary GHES, little is known about the mechanisms of action of these conjugated metabolites. Therefore, the aim of the present study was to investigate the effects of hesperetin-7-O-ß-d-glucuronide (HPT7G) and hesperetin-3'-O-ß-d-glucuronide (HPT3'G), which are the predominant HES metabolites in rat plasma, on blood pressure and endothelial function. Intravenous administration of HPT7G (5 mg kg(-1)) decreased blood pressure in anesthetized SHRs. HPT7G enhanced endothelium-dependent vasodilation in response to acetylcholine, but had no effect on endothelium-independent vasodilation in response to sodium nitroprusside (SNP) in aortas isolated from SHRs. HPT7G decreased hydrogen peroxide-induced intracellular adhesion molecule-1 and monocyte chemoattractant protein-1 mRNA expression in rat aortic endothelial cells. In contrast, HPT3'G had little effect on these parameters. In conclusion, HPT7G exerted hypotensive, vasodilatory and anti-inflammatory activities, similar to hesperetin and these effects are associated, in part, with the activity of GHES and HES to improve hypertension and endothelial dysfunction.

Pharmacokinetic and pharmacodynamic studies of four major phytochemical components of Da-Cheng-Qi decoction to treat acute pancreatitis.

The medicinal herb formulation Da-Cheng-Qi decoction (DCQD) has been shown to ameliorate the severity of acute pancreatitis by regulating an apoptosis-necrosis switch in cells. The active components responsible for this effect and their detailed mechanism of action remain unclear. Here we determine the pharmacokinetic characteristics of the four most abundant compounds in DCQD using a rat model of severe acute pancreatitis. Acute pancreatitis-like symptoms were first induced in rats and then they were given DCQD orally. Rhein was found in rat serum at much higher levels than magnolol, hesperidin, or naringin, even though it was the least abundant of the four compounds in the DCQD. We also examined pharmacodynamics in AR42J cells stimulated with 10(-8) M cerulein as a cellular model of acute pancreatitis. After pretreating AR42J cells with individual compounds and then exposing them to cerulein, we determined cell viability, levels of apoptosis and necrosis, and numbers of cells positive for reactive oxygen species (ROS). Pretreatment with any of the four DCQD compounds increased cell viability and the apoptosis index, while also reducing necrosis and ROS generation. The compounds showed maximal effect in AR42J cells around the same time that they showed maximum serum concentration in rats. Although all four components appear to play a role in an apoptosis-necrosis cellular switch in vitro, rhein may be the most bioactive DCQD ingredient.

Effect of formula compatibility on the pharmacokinetics of components from Dachengqi Decoction [See Text] in rats.

OBJECTIVE: To investigate the effect of prescription compatibility on the pharmacokinetics of components from Dachengqi Decoction (DCQD, ) in rats. METHODS: Twenty-four male rats were randomly and equally divided into the DCQD group, Dahuang (Radix et Rhizoma Rhei, Polygonaceae) group, Houpo (Magnolia officinalis Rehd., Magnoliaceae) group, and Zhishi (Fructus Aurantii Immaturus, Rutaceae) group. The blood samples were collected before dosing and subsequently at 10, 15, 20, 30, 45 min, 1, 2, 4, 8, and 12 h following gavage. The levels of aloe-emodin, rhein, emodin, chrysophanol, honokiol, magnolol, hesperidin, and naringin in rat serum were quantified using a liquid chromatography tandem mass spectrometry (LC-MS/MS) method for pharmacokinetic study. RESULTS: The area under the curve (AUC), mean retention time (MRT), the peak concentration (C(max)) of aloe-emodin, rhein, emodin, and chrysophanol in the DCQD group were significantly different compared with the Dahuang group (P <0.05, respectively). The mean plasma concentration, C(max), and the absorption of Dahuang's component in the DCQD group were obviously lower at each time point than those in the Dahuang group, while the elimination process of Dahuang's component was obviously delayed (P <0.05). Half-lives of aloe-emodin, chrysophanol, and rhein were also extended in the DCQD group (P <0.05, respectively). In the DCQD group, the mean plasma concentration, AUC, C(max) and absorption of honokiol, and magnolol were significantly lower (P <0.01, respectively) at each time point than those in the Houpo group, while the drug distribution half-life time (T(1/2α)), the drug eliminated half-life time (T(1/2ß)), MRT, and time of peak concentration (T(max)) were significantly delayed (P <0.05, respectively). Pharmacokinetic parameters of hesperidin and naringin in the Zhishi group were not significantly different as compared with the DCQD group (P >0.05, respectively), while the MRT of naringin was significantly longer. CONCLUSIONS: The compatibility in Chinese medicine could affect the drug's pharmacokinetics in DCQD, which proves that the prescription compatibility principle of Chinese medicine formulations has its own pharmacokinetic basis.