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

Evaluation of the Antioxidant Potential of Citrus medica from Different Geographical Regions and Characterization of Phenolic Constituents by LC-MS

The varying antioxidant potential of Citrus medica associated with different geographical regions makes the evaluation of C. medica for natural antioxidants essential. This work aimed to compare the antioxidant potential of the phenolic constituents from different geographical regions. The chemical compositions were characterized by ultra-high-performance liquid chromatography (UPLC) coupled with mass spectrometry (MS). A total of 67 compounds including 29 coumarin derivatives and 38 flavonoids were tentatively identified by UPLC-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). To evaluate the quality of C. medica from seven different geographical regions, water and 80% methanol fractions were subjected to quantitative analysis. Antioxidant potentials were determined by 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), iron chelation, and reduction methods. The samples collected from Sichuan province showed the highest content of total phenolic compounds. Combined with antioxidant results, the sample from Sichuan province presented good antioxidant activity. This study also showed that total phenolic compounds significantly contributed to the antioxidant activities (2,2-azinobis(3-ethyl-benzothiazoline-6-sulphonic acid) and radical scavenging activity) of C. medica samples (p < 0.01). These results provided chemical information and potential antioxidant value for further research, providing ideal evidence for the quality evaluation and exploitation of the source.

Hesperidin via maintenance of mitochondrial function and antioxidant activity protects lithium toxicity in rat heart isolated mitochondria

Lithium is commonly used in the treatment of bipolar disorders (BD) and consumer electronics. It has been reported that lithium exposure is associated with mitochondrial dysfunction and oxidative stress in isolated cardiac mitochondria. Mitochondrial protection has a key role in myocardial tissue homeostasis, cardiomyocyte survival and inhibition of cardiotoxicity. Hesperidin as a flavanone and cardioprotective agent has shown high potential in antioxidant activity and restoration of mitochondrial dysfunction in different models. Therefore, we aimed to evaluate the ameliorative effects of hesperidin against lithium-induced mitochondrial toxicity in rat cardiac mitochondria. Isolated mitochondria were classified into six groups; control, lithium carbonate (125 µM), three groups of lithium + hesperidin-treated received lithium (125 µM) and hesperidin with various concentrations (10, 50, and 100 µM) and hesperidin (100 µM). Succinate dehydrogenases (SDH) activity, mitochondrial swelling, mitochondrial membrane potential (MMP), reactive oxygen species (ROS), mitochondrial glutathione (GSH) and lipid peroxidation (LPO) were measured. The mitochondria received lithium showed a significant reduction of SDH activity, MMP collapse, mitochondrial swelling, induction of ROS formation and lipid peroxidation. However, we observed that the administration of hesperidin (50 and 100 µM) resulted in the increase of SDH activity, improved MMP collapse, mitochondrial swelling, and reduced ROS formation and lipid peroxidation. Also, there were no obvious changes in cardiac mitochondria received of hesperidin. These findings suggest that hesperidin could reduce lithium-induced mitochondrial dysfunction through antioxidant activities in cardiac mitochondria, may be beneficial for prevention and treatment of lithium toxicities, either as a drug to treat BD or as an environmental pollutant.

Cardioprotective Effects of Grapefruit IntegroPectin Extracted via Hydrodynamic Cavitation from By-Products of Citrus Fruits Industry: Role of Mitochondrial Potassium Channels

Citrus flavonoids are well-known for their beneficial effects at the cardiovascular and cardio-metabolic level, but often the encouraging in vitro results are not confirmed by in vivo approaches; in addition, the clinical trials are also inconsistent. Their limited bioavailability can be, at least in part, the reason for these discrepancies. Therefore, many efforts have been made towards the improvement of their bioavailability. Hydrodynamic cavitation methods were successfully applied to the extraction of byproducts of the Citrus fruits industry, showing high process yields and affording stable phytocomplexes, known as IntegroPectin, endowed with great amounts of bioactive compounds and high water solubility. The cardioprotective effects of grapefruit IntegroPectin were evaluated by an ex vivo ischemia/reperfusion protocol. Further pharmacological characterization was carried out to assess the involvement of mitochondrial potassium channels. Grapefruit IntegroPectin, where naringin represented 98% of the flavonoids, showed anti-ischemic cardioprotective activity, which was better than pure naringenin (the bioactive aglycone of naringin). On cardiac-isolated mitochondria, this extract confirmed that naringenin/naringin were involved in the activation of mitochondrial potassium channels. The hydrodynamic cavitation-based extraction confirmed a valuable opportunity for the exploitation of Citrus fruits waste, with the end product presenting high levels of Citrus flavonoids and improved bioaccessibility that enhances its nutraceutical and economic value.

Feeding Fiber-Bound Polyphenol Ingredients at Different Levels Modulates Colonic Postbiotics to Improve Gut Health in Cats

Simple Summary

Food eaten by humans or companion animals is broken down by enzymes produced by the host and also by bacteria present in the large intestine of the host. Many of the compounds produced can have beneficial effects on the host’s health. Previous studies in dogs evaluated changes after they ate food containing a fiber bundle made of pecan shells, flax seed, and powders from cranberry, citrus, and beet. These studies showed that bacteria in the large intestine switched from digesting mainly protein to digesting mainly carbohydrates resulting in production of compounds with beneficial properties. The study presented here tested this fiber bundle in cats to see which compounds and/or bacteria in the feces changed. After cats consumed food containing the fiber bundle, several compounds associated with beneficial health effects increased, and some compounds that indicate the breakdown of protein decreased. In contrast, little change in fecal bacteria was observed following consumption of food with the fiber bundle. Overall, these findings indicate that, similar to the dog studies, bacteria in the large intestine of cats were able to digest the fiber bundle to make compounds that may contribute to host health and also shifted to digestion of carbohydrates instead of protein.

Abstract

Consumption of fiber in its different forms can result in positive health effects. Prior studies in dogs found that addition of a fiber bundle (composed of pecan shells, flax seed, and powders of cranberry, citrus, and beet) to food resulted in a shift in fecal bacterial metabolism from proteolysis to saccharolysis. The present study evaluated the changes in fecal metabolites and microbiota in healthy cats following the consumption of this fiber bundle. Following a 28-day pre-feed period, 56 healthy adult cats received food with none or one of three concentrations (0%, 1%, 2%, and 4%) of the fiber bundle for a 31-day period. In cats that consumed the 4% fiber bundle, levels of ammonium and fecal branched-chain fatty acids (BCFAs) decreased from baseline and compared with the other groups. Addition of any level of the fiber bundle resulted in increases in beneficial metabolites: polyphenols hesperidin, hesperetin, ponciretin, secoisolariciresinol diglucoside, secoisolariciresinol, and enterodiol. Little change in fecal microbiota was observed. Since higher levels of ammonia and BCFAs indicate putrefactive metabolism, the decreases in these with the 4% fiber bundle indicate a shift toward saccharolytic metabolism despite little change in the microbiota composition.

MS-IDF: A Software Tool for Nontargeted Identification of Endogenous Metabolites after Chemical Isotope Labeling Based on a Narrow Mass Defect Filter

Chemical isotope labeling liquid chromatography mass spectrometry (LC-MS) is an emerging metabolomic strategy for the quantification and characterization of small molecular compounds in biological samples. However, its subsequent data analysis is not straightforward due to a large amount of data produced and interference of biological matrices. In order to improve the efficiency of searching and identification of target endogenous metabolites, a new software tool for nontargeted metabolomics data processing called MS-IDF was developed based on the principle of a narrow mass defect filter. The developed tool provided two function modules, including IsoFinder and MDFinder. The IsoFinder function module applied a conventional peak extraction method by using a fixed mass differences between the heavy and light labels and by the alignment of chromatographic retention time (RT). On the other hand, MDFinder was designed to incorporate the accurate mass defect differences between or among stable isotopes in the peak extraction process. By setting an appropriate filter interval, the target metabolites can be efficiently screened out while eliminating interference. Notably, the present results showed that the efficiency in compound identification using the new MDFinder module was nearly doubled as compared to the conventional IsoFinder method (an increase from 259 to 423 compounds). The Matlab codes of the developed MS-IDF software are available from github at https://github.com/jydong2018/MS_IDF. Based on the MS-IDF software tool, a novel and effective approach from nontargeted to targeted metabolomics research was developed and applied to the exploration of potential primary amine biomarkers in patients with schizophrenia. With this approach, potential biomarkers, including N,N-dimethylglycine, S-adenosine-l-methionine, dl-homocysteine, and spermidine, were discovered.

Blood pressure and body fat % reduction is mainly related to flavanone phase II conjugates and minor extension by phenolic acid after long-term intake of orange juice

Hesperidin and narirutin are the major flavanones present in orange juice, and they are associated with a reduction in risk of cardiometabolic disease. However, there is heterogeneity in their biological responses, which is partly due to the large interindividual variation in these flavonoids' bioavailability. We investigated the relation between interindividual variability in the excretion of phase II conjugates and gut-derived phenolic acids, and cardiometabolic biomarkers response. Seventy-four subjects, both men and women, were included in a single-arm study. Over the 60 days, volunteers consumed 500 mL of orange juice daily. All measurements and blood collections were performed before and after the intervention period. Moreover, 24 h urine collection was performed after first consumption. Individuals were stratified according to the excretion of phase II conjugates and, for the first time, according to phenolic acids in high, medium, and low excretors. Furthermore, for the first time, the ratio between phenolic acids and flavanones-phase II conjugates has shown groups with different metabolization patterns. Groups with a low or intermediate ratio, corresponding to a higher amount of phase II conjugates excreted, showed a significant reduction in body fat % and blood pressure. This finding suggests that these improvements could be associated in a major way to flavanones-phase II conjugates, as well as to phenolic acids and stratification of volunteers according to metabolite excretions could be a good strategy to better understand the effects of orange juice on metabolism and health.