Gellan gum prevents non-alcoholic fatty liver disease by modulating the gut microbiota and metabolites.

Gellan gum (GG) is an anionic polysaccharide used as an additive in the food industry. However, the effect of GG on gut microbiota regulation and nonalcoholic fatty liver disease (NAFLD) has not yet been investigated. In vitro fermentation experiments have demonstrated that GG promoted the growth of probiotic strains such as Lactiplantibacillus rhamnosus and Bifidobacterium bifidum, producing metabolites beneficial to gut health. In mice, GG reduced hepatic triglyceride content, serum biomarkers, and body fat mass and weight gain induced by a high fat diet. Additionally, GG regulated the gut microbiota including Desulfovibrionales, Deferribacterales, Bacteroidales, and Lactobacillales at the order level and also promoted short-chain fatty acid production. Moreover, GG improved the expression of proteins related to hepatic inflammation and lipid metabolism. Taken together, GG ameliorated NAFLD, possibly by acting on the gut-liver axis via improving the gut health, indicating its potential as a food supplement and/or prebiotic against NAFLD.

Morinda citrifolia Extract Prevents Alcoholic Fatty Liver Disease by Improving Gut Health.

Alcoholic liver disease (ALD) is a major chronic liver disease. Chronic alcohol consumption induces dysbiosis, disruption of gut barrier function, oxidative stress, inflammation, and changes in lipid metabolism, thereby leading to ALD. In this study, we investigated whether the commercial Morinda citrifolia extract Nonitri can ameliorate ALD symptoms through the gut-liver axis. We used mice chronically administered EtOH and found a marked increase in serum endotoxin levels and biomarkers of liver pathology. Moreover, the EtOH-treated group showed significantly altered gut microbial composition particularly that of Alistipes, Bacteroides, and Muribaculum and disrupted gut barrier function. However, Nonitri improved serum parameters, restored the microbial proportions, and regulated levels of zonula occludens1, occludin, and claudin1. Furthermore, Nonitri suppressed inflammation by inhibiting endotoxin-triggered toll-like receptor 4-signaling pathway and fat deposition by reducing lipogenesis through activating AMP-activated protein kinase in the liver. Furthermore, Pearson's correlation analysis showed that gut microbiota and ALD-related markers were correlated, and Nonitri regulated these bacteria. Taken together, our results indicate that the hepatoprotective effect of Nonitri reduces endotoxin levels by improving gut health, and inhibits fat deposition by regulating lipid metabolism.

Lactococcus lactis KF140 Reduces Dietary Absorption of Nε - (Carboxymethyl)lysine in Rats and Humans via ß-Galactosidase Activity.

Background and Aims: Excessive intake of advanced glycation end products (AGEs), which are formed in foods cooked at high temperatures for long periods of time, has negative health effects, such as inflammatory responses and oxidative stress. Nε-(Carboxymethyl)lysine (CML) is one of the major dietary AGEs. Given their generally recognized as safe status and probiotic functionalities, lactic acid bacteria may be ideal supplements for blocking intestinal absorption of food toxicants. However, the protective effects of lactic acid bacteria against dietary AGEs have not been fully elucidated. Materials and Methods: We investigated the effect of treatment with Lactococcus lactis KF140 (LL-KF140), which was isolated from kimchi, on the levels and toxicokinetics of CML. The CML reduction efficacies of the Lactococcus lactis KF140 (LL-KF140), which was isolated from kimchi, were conducted by in vitro test for reducing CML concentration of the casein-lactose reaction product (CLRP) and in vivo test for reducing serum CML level of LL-KF140 administered rats at 2.0 × 108 CFU/kg for14 days. In addition, 12 volunteers consuming LL-KF140 at 2.0 × 109 CFU/1.5 g for 26 days were determined blood CML concentration and compared with that before intake a Parmesan cheese. Results: Administration of LL-KF140 reduced serum CML levels and hepatic CML absorption in rats that were fed a CML-enriched product. In a human trial, the intake of LL-KF140 prevented increases in the serum levels of CML and alanine aminotransferase after consumption of a CML-rich cheese. LL-KF140 was determined to presence in feces through metagenome analysis. Furthermore, ß-galactosidase, one of the L. lactis-produced enzymes, inhibited the absorption of CML and reduced the levels of this AGE, which suggests an indirect inhibitory effect of LL-KF140. This study is the first to demonstrate that an L. lactis strain and its related enzyme contribute to the reduction of dietary absorption of CML.

A water soluble extract of radish greens ameliorates high fat diet-induced obesity in mice and inhibits adipogenesis in preadipocytes.

Radish (Raphanus sativus L.) is a rich source of nutrients and its greens have reported functionalities. This study aimed to investigate the effects of a water-soluble extract from radish greens (WERG) on adipogenesis in 3T3-L1 adipocytes and high-fat diet-induced obesity in model mice. We also quantified the phytochemical composition of WERG such as glucoraphenin and ferulic acid. These findings show that treatment with 100 µg mL-1 WERG reduced lipid accumulation in 3T3-L1 adipocytes, whereas in mice, the administration of 100 mg kg-1 WERG reduced weight gain and hepatic lipid accumulation and improved the levels of serum lipid biomarkers. Furthermore, WERG treatment improved intestinal permeability and suppressed the activities of harmful intestinal enzymes in feces, thus improving gut health. It also inhibited metabolic endotoxemia and inflammatory marker levels in serum. Moreover, WERG reduced the expression of lipid-metabolism-related proteins in the liver and white adipose tissue. Collectively, these results indicate that WERG may potentiate the anti-obesity effect by improving gut health and regulating lipid metabolism.

Inhibitory effect of sea buckthorn extracts on advanced glycation endproduct formation.

This study shows the inhibitory effect of sea buckthorn (Hippophae rhamnoides L.) extracts, sea buckthorn leaf (HRL) and berry (HRB), on the formation of advanced glycation endproducts (AGEs), closely linked to diverse disease. In vitro assay revealed the superior inhibitory effect of HRL on the AGEs formation and AGEs-induced collagen crosslinking compared with that of HRB. Ultra-performance liquid chromatography-mass spectrometry results revealed that HRL displays a higher inhibition efficiency on the AGEs formation at 30 AGEs binding sites in bovine serum albumin than HRB. The high concentration of 3-sophoroside-7-rhamnoside in HRL compared with that in HRB may result in the strong inhibitory effect of HRL compared with that of HRB. HRL also exhibited significantly higher ABTS and DPPH radical scavenging activities than HRB. Overall, this study demonstrated that HRL has excellent potential as a dietary agent for controlling various diseases mediated by AGEs and oxidative stress.

Antioxidant Effects of Turmeric Leaf Extract against Hydrogen Peroxide-Induced Oxidative Stress In Vitro in Vero Cells and In Vivo in Zebrafish.

Oxidative stress, caused by the excessive production of reactive oxygen species (ROS), results in cellular damage. Therefore, functional materials with antioxidant properties are necessary to maintain redox balance. Turmeric leaves (Curcuma longa L. leaves; TL) are known to have antioxidant properties, including 2,2-Diphenyl-1-picrylhydrazyl (DPPH), 2,2'-Azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS), and Hydrogen peroxide (H2O2) radical scavenging activity in several studies. The antioxidant effects of TL come from distinct bioactive compounds, such as curcumin, total phenolic compounds, and flavonoids. Therefore, in this study, the antioxidant effects of a water extract of TL (TLE) against H2O2 treatment were assessed in vitro Vero cells and in vivo zebrafish models. The intracellular ROS generation and the proportion of sub-G1 phase cells were evaluated in H2O2- or/and TLE-treated Vero cells to measure the antioxidant activity of TLE. TLE showed outstanding intracellular ROS scavenging activity and significantly decreased the proportion of cells in the sub-G1 phase in a dose-dependent manner. Furthermore, cell death, ROS generation, and lipid peroxidation in the H2O2-treated zebrafish model were attenuated as a consequence of TLE treatment. Collectively, the results from this study suggested that TLE may be an alternative material to relieve ROS generation through its antioxidant properties or a suitable material for the application in a functional food industry.

Chiral differentiation of d- and l-isoleucine using permethylated ß-cyclodextrin: infrared multiple photon dissociation spectroscopy, ion-mobility mass spectrometry, and DFT calculations.

Chiral differentiation of protonated isoleucine (Ile) using permethylated ß-cyclodextrin (perCD) in the gas-phase was studied using infrared multiple photon dissociation (IRMPD) spectroscopy, ion-mobility, and density functional theory (DFT) calculations. The gaseous protonated non-covalent complexes of perCD and d-Ile or l-Ile produced by electrospray ionization were interrogated by laser pulses in the wavenumber region of 2650 to 3800 cm-1. The IRMPD spectra showed remarkably different IR spectral features for the d-Ile or l-Ile and perCD non-covalent complexes. However, drift-tube ion-mobility experiments provided only a small difference in their collision cross-sections, and thus a limited separation of the d- and l-Ile complexes. DFT calculations revealed that the chiral distinction of the d- and l-complexes by IRMPD spectroscopy resulted from local interactions of the protonated Ile with perCD. Furthermore, the theoretical results showed that the IR absorption spectra of higher energy conformers (by ∼13.7 kcal mol-1) matched best with the experimentally observed IRMPD spectra. These conformers are speculated to be formed from kinetic-trapping of the solution-phase conformers. This study demonstrated that IRMPD spectroscopy provides an excellent platform for differentiating the subtle chiral difference of a small amino acid in a cyclodextrin-complexation environment; however, drift-tube ion-mobility did not have sufficient resolution to distinguish the chiral difference.

Accurate Quantification of N-Glycolylneuraminic Acid in Therapeutic Proteins Using Supramolecular Mass Spectrometry.

Practical applications of innovative host-guest systems are challenging because of unexpected guest competitors and/or subtle environmental differences. Herein, a supramolecular mass spectrometry (MS)-based method using a synthetic host, cucurbit[7]uril (CB[7]), was developed for identifying and quantifying N-glycolylneuraminic acid (Neu5Gc) in therapeutic glycoproteins, which critically reduces drug efficacy. The development of a reliable derivatization-free analytical method for Neu5Gc is highly challenging because of the interference by the abundant N-acetylneuraminic acid (Neu5Ac). CB[7] recognized the subtle structural differences between Neu5Gc and Neu5Ac. Distinct host-guest interactions between CB[7] and the two sialic acids produced a highly linear relationship between the complexation and concentration proportions of the two sialic acids in MS. Furthermore, the developed method had sub-picomolar quantification limits and a wide range of applicability for diverse glycoproteins, demonstrating the potential utility of this method as a reliable assay of Neu5Gc in therapeutic glycoproteins.

Structural characterization of small molecular ions by ion mobility mass spectrometry in nitrogen drift gas: improving the accuracy of trajectory method calculations.

The investigation of ion structures based on a combination of ion mobility mass spectrometry (IM-MS) experiments and theoretical collision cross section (CCS) calculations has become important to many fields of research. However, the accuracy of current CCS calculations for ions in nitrogen drift gas limits the information content of many experiments. In particular, few studies have evaluated and attempted to improve the theoretical tools for CCS calculation in nitrogen drift gas. In this study, based on high-quality experimental measurements and theoretical modeling, a comprehensive evaluation of various aspects of CCS calculations in nitrogen drift gas is performed. It is shown that the modification of the ion-nitrogen van der Waals (vdW) interaction potential enables accurate CCS predictions of 29 small ions with ca. 3% maximum relative error. The present method exhibits no apparent systematic bias with respect to ion CCS (size) and dipole moment, suggesting that the method adequately describes the long-range interactions between the ions and the buffer gas. However, the method shows limitations in reproducing experimental CCS at low temperatures (<150 K) and for macromolecular ions, and calculations for these cases should be complemented by CCS calculation methods in helium drift gas. This study presents an accurate and well-characterized CCS calculation method for ions in nitrogen drift gas that is expected to become an important tool for ion structural characterization and molecular identification. The experimental values reported here also provide a foundation for future studies aiming at developing more efficient computational tools.

Manifesting Subtle Differences of Neutral Hydrophilic Guest Isomers in a Molecular Container by Phase Transfer.

Achieving strong host-guest interactions between synthetic hosts and hydrophilic guests in solution is challenging because solvation effects overwhelm other effects. To resolve this issue, we transferred complexes of cucurbit[7]uril (CB[7]) and monosaccharides to the gas phase and report here their intrinsic host-guest chemistry in the absence of solvation effects. It was observed that effective host-guest interactions in the gas phase mediated by ammonium cations allow the differentiation of the monosaccharide isomers in complex with CB[7] upon vibrational excitation. The potential of the unique observation was extended to a quantitative supramolecular analytical method for the monosaccharide guests. The combination of host-guest chemistry and phase transfer presented in this study is an effective approach to overcome current limitations in supramolecular chemistry.

Deciphering the specific high-affinity binding of cucurbit[7]uril to amino acids in water.

This work presents a systematic study on the host-guest interactions between the macrocyclic host molecule cucurbit[7]uril (CB[7]) and amino acids (AAs) including three basic AAs (Lys, Arg, and His) and three aromatic AAs (Phe, Tyr, and Trp) to elucidate the origin of the high selectivity of CB[7] toward AA residues in proteins. Complex formation between CB[7] and each AA was examined in solution (by isothermal titration calorimetry and NMR) as well as in the gas phase (by ion mobility mass spectrometry and collision-induced dissociation), and the results were further combined with computational investigations. Generally, the aromatic AAs show higher binding affinities than the basic AAs in buffer solutions with various pH values. On the contrary, the gas-phase stabilities of the basic AA complex ions are higher than those of the aromatic AA complex ions, suggesting that the direct ion-dipole interactions between the charged side chains of the basic AAs and the polar carbonyl groups of CB[7] predominate in the absence of water. The ion-dipole interactions are less significant in water, since the original interactions of the guests with water are lost upon complex formation. In contrast, the transfer of the hydrophobic groups from the bulk into the hydrophobic CB[7] cavity suffers less from the desolvation penalty, resulting in higher binding affinities in water. Therefore, initial guest solvation is another key factor which should be considered when designing high-affinity host-guest systems, in addition to the contribution from the release of high-energy water molecules from the CB[7] cavity (J. Am. Chem. Soc. 2012, 134, 15318-15323).