Comparative genomics of the medicinal plants Lonicera macranthoides and L. japonica provides insight into genus genome evolution and hederagenin-based saponin biosynthesis.

Lonicera macranthoides (LM) and L. japonica (LJ) are medicinal plants widely used in treating viral diseases, such as COVID-19. Although the two species are morphologically similar, their secondary metabolite profiles are significantly different. Here, metabolomics analysis showed that LM contained ~86.01 mg/g hederagenin-based saponins, 2000-fold higher than LJ. To gain molecular insights into its secondary metabolite production, a chromosome-level genome of LM was constructed, comprising 9 pseudo-chromosomes with 40 097 protein-encoding genes. Genome evolution analysis showed that LM and LJ were diverged 1.30-2.27 million years ago (MYA). The two plant species experienced a common whole-genome duplication event that occurred ∼53.9-55.2 MYA before speciation. Genes involved in hederagenin-based saponin biosynthesis were arranged in clusters on the chromosomes of LM and they were more highly expressed in LM than in LJ. Among them, oleanolic acid synthase (OAS) and UDP-glycosyltransferase 73 (UGT73) families were much more highly expressed in LM than in LJ. Specifically, LmOAS1 was identified to effectively catalyse the C-28 oxidation of ß-Amyrin to form oleanolic acid, the precursor of hederagenin-based saponin. LmUGT73P1 was identified to catalyse cauloside A to produce α-hederin. We further identified the key amino acid residues of LmOAS1 and LmUGT73P1 for their enzymatic activities. Additionally, comparing with collinear genes in LJ, LmOAS1 and LmUGT73P1 had an interesting phenomenon of 'neighbourhood replication' in LM genome. Collectively, the genomic resource and candidate genes reported here set the foundation to fully reveal the genome evolution of the Lonicera genus and hederagenin-based saponin biosynthetic pathway.

Ginsenoside Rb1 inhibits astrocyte activation and promotes transfer of astrocytic mitochondria to neurons against ischemic stroke.

Astrocytes activation in response to stroke results in altered mitochondrial exchange with neurons. Ginsenoside Rb1is a major ginsenoside of Panax ginseng particularly known for its neuroprotective potential. This work aimed to investigate if Rb1 could rescue neurons from ischemic insult via astrocyte inactivation and mitochondrial transfer. We prepared conditioned astrocytes-derived medium for co-culture with neurons and examined the role of Rb1 in mitochondrial transfer from astrocytes to neurons. The neuroprotective potential of Rb1 was further confirmed in vivo using a mouse model of brain ischemia. In response to oxygen-glucose deprivation and reperfusion (OGD/R), astrocytes were reactivated and produced reactive oxygen species (ROS), an action that was blocked by Rb1. Mechanistically, Rb1 inhibited NADH dehydrogenase in mitochondrial complex I to block reverse electron transport-derived ROS production from complex I, and thus inactivated astrocytes to protect the mitochondria. Mitochondrial signal, mitochondrial membrane potential and ATP production detected in conditioned astrocyte-derived medium indicated that Rb1 protected functional mitochondria and facilitated their transfer. When neurons were injured by OGD/R insult, co-culturing with conditioned medium increased mitochondrial membrane potential and oxygen consumption rate within the neurons, indicating the protection conferred on them by Rb1 via mitochondrial transfer from astrocytes. Using the ischemic mouse brain model, CD38 knockdown in the cerebral ventricles diminished the neuroprotective effects of Rb1, providing evidence in support of the role of astrocyte mitochondrial transfer. Transient inhibition of mitochondrial complex I by Rb1 reduced mitochondrial ROS production and consequently avoided astrocyte activation. Astrocyte mitochondrial transfer therefore seemed a means by which Rb1 could promote neuronal survival and function. Different from the neurocentric view, these findings suggest the astrocytes may be a promising target for pharmacological interventions in ischemic brain injury.

Integrated metagenomics identifies a crucial role for trimethylamine-producing Lachnoclostridium in promoting atherosclerosis.

Microbial trimethylamine (TMA)-lyase activity promotes the development of atherosclerosis by generating of TMA, the precursor of TMA N-oxide (TMAO). TMAO is well documented, but same can not be said of TMA-producing bacteria. This work aimed to identify TMA-producing genera in human intestinal microbiota. We retrieved the genomes of human-associated microorganisms from the Human Microbiome Project database comprising 1751 genomes, Unified Human Gastrointestinal Genome collection consisting 4644 gut prokaryotes, recapitulated 4930 species-level genome bins and public gut metagenomic data of 2134 individuals from 11 populations. By sequence searching, 216 TMA-lyase-containing species from 102 genera were found to contain the homologous sequences of cntA/B, yeaW/X, and/or cutC/D. We identified 13 strains from 5 genera with cntA sequences, and 30 strains from 14 genera with cutC showing detectable relative abundance in healthy individuals. Lachnoclostridium (p = 2.9e-05) and Clostridium (p = 5.8e-04), the two most abundant cutC-containing genera, were found to be much higher in atherosclerotic patients compared with healthy persons. Upon incubation with choline (substrate), L. saccharolyticum effectively transformed it to TMA at a rate higher than 98.7% while that for C. sporogenes was 63.8-67.5% as detected by liquid chromatography-triple quadrupole mass spectrometry. In vivo studies further showed that treatment of L. saccharolyticum and choline promoted a significant increase in TMAO level in the serum of ApoE-/- mice with obvious accumulation of aortic plaque in same. This study discloses the significance and efficiency of the gut bacterium L. saccharolyticum in transforming choline to TMA and consequently promoting the development of atherosclerosis.

Cordyceps Improves Obesity and its Related Inflammation via Modulation of Enterococcus cecorum Abundance and Bile Acid Metabolism.

Dysbiotic gut microbiota has been identified as a primary mediator of inherent inflammation that underlies the pathogenesis of obesity. Cordyceps comprises the larval body and the stroma of Cordyceps sinensis (BerK.) Sacc. parasiting on Hepialidae larvae of moths (H. pialusoberthur) with potent metabolic regulation functions. The underlying anti-obesity mechanisms, however, remain largely unknown. Here, we demonstrate that the water extract of Cordyceps attenuates glucose and lipid metabolism disorders and its associated inflammation in high-fat diet (HFD)-fed mice. 16S rRNA gene sequencing and microbiomic analysis showed that Cordyceps reduced the amounts of Enterococcus cecorum, a bile-salt hydrolase-producing microbe to regulate the metabolism of bile acids in the gut. Importantly, E. cecorum transplantation or liver-specific knockdown of farnesoid X receptor (FXR), a bile acid receptor, diminished the protective effect of Cordyceps against HFD-induced obesity. Together, our results shed light on the mechanisms that underlie the glucose- and lipid-lowering effects of Cordyceps and suggest that targeting intestinalE. cecorum or hepatic FXR are potential anti-obesity and anti-inflammation therapeutic avenues.

Paired Derivatization Approach with H/D-Labeled Hydroxylamine Reagents for Sensitive and Accurate Analysis of Monosaccharides by Liquid Chromatography Tandem Mass Spectrometry.

Monosaccharides play important roles in biological processes. Sensitive and accurate analyses of monosaccharides remain challenging because of their high hydrophilicities and poor ionization efficiencies. Here, we developed a paired derivatization approach with H/D-labeled hydroxylamines for simultaneous quantification of 12 monosaccharides by liquid chromatography tandem mass spectrometry (LC-MS/MS). O-(4-Methoxybenzyl)hydroxylamine hydrochloride (4-MOBHA·HCl) showed higher derivatization efficiency for monosaccharides compared to six other hydroxylamine analogues. The derivatization of monosaccharides was readily achieved in an aqueous solution. Furthermore, the deuterium-labeled isotope reagent, d3-4-MOBHA·HCl, was newly synthesized to stably label monosaccharides to improve its accuracy and precision in complex matrix analysis. As a result, 12 monosaccharides were rapidly detected by LC-MS/MS within 16 min with significant improvements in chromatographic separation and retention time. The detection sensitivity increased by 83 to 1600-fold with limits of quantitation ranging from 0.25 to 3.00 fmol. With the paired derivatization strategy, the monosaccharides could be accurately quantified with good linearity (R2 > 0.99) and satisfactory accuracy (recoveries: 85-110%). Using this method, we achieved sensitive and accurate quantification of the monosaccharide composition of herbal polysaccharides and the change in monosaccharide levels in human cell lines under physiopathological conditions. More importantly, the developed method was able to differentiate between the levels of the monosaccharides in fecal samples of human ulcerative colitis (UC) patients and UC mice compared to their respective controls. The differential monosaccharides determined in human feces provided a good diagnostic performance in distinguishing the UC patients from healthy individuals, showing potential for clinical application.

The mitochondrial ß-oxidation enzyme HADHA restrains hepatic glucagon response by promoting ß-hydroxybutyrate production.

Disordered hepatic glucagon response contributes to hyperglycemia in diabetes. The regulators involved in glucagon response are less understood. This work aims to investigate the roles of mitochondrial ß-oxidation enzyme HADHA and its downstream ketone bodies in hepatic glucagon response. Here we show that glucagon challenge impairs expression of HADHA. Liver-specific HADHA overexpression reversed hepatic gluconeogenesis in mice, while HADHA knockdown augmented glucagon response. Stable isotope tracing shows that HADHA promotes ketone body production via ß-oxidation. The ketone body ß-hydroxybutyrate (BHB) but not acetoacetate suppresses gluconeogenesis by selectively inhibiting HDAC7 activity via interaction with Glu543 site to facilitate FOXO1 nuclear exclusion. In HFD-fed mice, HADHA overexpression improved metabolic disorders, and these effects are abrogated by knockdown of BHB-producing enzyme. In conclusion, BHB is responsible for the inhibitory effect of HADHA on hepatic glucagon response, suggesting that HADHA activation or BHB elevation by pharmacological intervention hold promise in treating diabetes.

Omics and Transgenic Analyses Reveal that Salvianolic Acid B Exhibits its Anti-Inflammatory Effects through Inhibiting the Mincle-Syk-Related Pathway in Macrophages.

Salvianolic acid B (Sal B), the main water-soluble compound in Salvia miltiorrhiza, is known to exhibit anti-inflammatory activity, however, the underlying mechanism(s) is not completely uncovered. In this study, Sal B inhibited lipopolysaccharide (LPS)-induced M1 activation and promoted the transformation of macrophages from M1- to M2-type polarization. The altered lipid profiles of LPS-induced RAW 264.7 macrophages were partly restored by Sal B treatment. At the proteomic level, a total of 5612 proteins were identified and 432 were significantly changed in macrophages under LPS treatment. The differential proteins were classified into four clusters according to their expression level in blank, LPS, and Sal B groups. LPS-induced proteins in Cluster IV including Kif14, Mincle, and Sec62 were significantly recovered to almost normal levels by Sal B treatment. Use of knockdown Mincle or picetannol (inhibitor of Syk) led to significant reductions in the gene expressions of IL-1ß, iNOS, and IL-12 and the release of NO. The converse was, however, observed for overexpressed Mincle. In addition, LPS- or trehalose-6,6-dibehenate-induced phosphorylation of Syk and PKCδ was decreased by Sal B treatment. These results suggest that Sal B inhibition of LPS-induced inflammation might be through inhibition of the Mincle-Syk-PKCδ signaling pathway.

Serum-Urine Matched Metabolomics for Predicting Progression of Henoch-Schonlein Purpura Nephritis.

Henoch-Schonlein purpura nephritis (HSPN) is a common glomerulonephritis secondary to Henoch-Schonlein purpura (HSP) that affects systemic metabolism. Currently, there is a rarity of biomarkers to predict the progression of HSPN. This work sought to screen metabolic markers to predict the progression of HSPN via serum-urine matched metabolomics. A total of 90 HSPN patients were enrolled, including 46 HSPN (+) patients with severe kidney damage (persistent proteinuria >0.3 g/day) and 44 HSPN (-) patients without obvious symptoms (proteinuria < 0.3 g/day). Untargeted metabolomics was determined by liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-Q/TOF-MS). A total of 38 and 50 differential metabolites were, respectively, identified in serum and urine from the comparison between HSPN (+) and HSPN (-) patients. Altered metabolic pathways in HSPN (+) mainly included glycerophospholipid metabolism, pyruvate metabolism, and citrate cycle. A panel of choline and cis-vaccenic acid gave areas under the curve of 92.69% in serum and 72.43% in urine for differential diagnosis between HSPN (+) and HSPN (-). In addition, the two metabolites showed a significant association with clinical indices of HSPN. These results suggest that serum-urine matched metabolomics comprehensively characterized the metabolic differences between HSPN (+) and HSPN (-), and choline and cis-vaccenic acid could serve as biomarkers to predict HSPN progression.

Intestinal α1-2-Fucosylation Contributes to Obesity and Steatohepatitis in Mice.

BACKGROUND & AIMS: Fucosyltransferase 2 (Fut2)-mediated intestinal α1- 2-fucosylation is important for host-microbe interactions and has been associated with several diseases, but its role in obesity and hepatic steatohepatitis is not known. The aim of this study was to investigate the role of Fut2 in a Western-style diet-induced mouse model of obesity and steatohepatitis. METHODS: Wild-type (WT) and Fut2-deficient littermate mice were used and features of the metabolic syndrome and steatohepatitis were assessed after 20 weeks of Western diet feeding. RESULTS: Intestinal α1-2-fucosylation was suppressed in WT mice after Western diet feeding, and supplementation of α1-2-fucosylated glycans exacerbated obesity and steatohepatitis in these mice. Fut2-deficient mice were protected from Western diet-induced features of obesity and steatohepatitis despite an increased caloric intake. These mice have increased energy expenditure and thermogenesis, as evidenced by a higher core body temperature. Protection from obesity and steatohepatitis associated with Fut2 deficiency is transmissible to WT mice via microbiota exchange; phenotypic differences between Western diet-fed WT and Fut2-deficient mice were reduced with antibiotic treatment. Fut2 deficiency attenuated diet-induced bile acid accumulation by altered relative abundance of bacterial enzyme 7-α-hydroxysteroid dehydrogenases metabolizing bile acids and by increased fecal excretion of secondary bile acids. This also was associated with increased intestinal farnesoid X receptor/fibroblast growth factor 15 signaling, which inhibits hepatic synthesis of bile acids. Dietary supplementation of α1-2-fucosylated glycans abrogates the protective effects of Fut2 deficiency. CONCLUSIONS: α1-2-fucosylation is an important host-derived regulator of intestinal microbiota and plays an important role for the pathogenesis of obesity and steatohepatitis in mice.

Proteomic analysis reveals ginsenoside Rb1 attenuates myocardial ischemia/reperfusion injury through inhibiting ROS production from mitochondrial complex I.

Rationale: Reactive oxygen species (ROS) burst from mitochondrial complex I is considered the critical cause of ischemia/reperfusion (I/R) injury. Ginsenoside Rb1 has been reported to protect the heart against I/R injury; however, the underlying mechanism remains unclear. This work aimed to investigate if ginsenoside Rb1 attenuates cardiac I/R injury by inhibiting ROS production from mitochondrial complex I. Methods: In in vivo experiments, mice were given ginsenoside Rb1 and then subjected to I/R injury. Mitochondrial ROS levels in the heart were determined using the mitochondrial-targeted probe MitoB. Mitochondrial proteins were used for TMT-based quantitative proteomic analysis. In in vitro experiments, adult mouse cardiomyocytes were pretreated with ginsenoside Rb1 and then subjected to hypoxia and reoxygenation insult. Mitochondrial ROS, NADH dehydrogenase activity, and conformational changes of mitochondrial complex I were analyzed. Results: Ginsenoside Rb1 decreased mitochondrial ROS production, reduced myocardial infarct size, preserved cardiac function, and limited cardiac fibrosis. Proteomic analysis showed that subunits of NADH dehydrogenase in mitochondrial complex I might be the effector proteins regulated by ginsenoside Rb1. Ginsenoside Rb1 inhibited complex I- but not complex II- or IV-dependent O2 consumption and enzyme activity. The inhibitory effects of ginsenoside Rb1 on mitochondrial I-dependent respiration and reperfusion-induced ROS production were rescued by bypassing complex I using yeast NADH dehydrogenase. Molecular docking and surface plasmon resonance experiments indicated that ginsenoside Rb1 reduced NADH dehydrogenase activity, probably via binding to the ND3 subunit to trap mitochondrial complex I in a deactive form upon reperfusion. Conclusion: Inhibition of mitochondrial complex I-mediated ROS burst elucidated the probable underlying mechanism of ginsenoside Rb1 in alleviating cardiac I/R injury.

Untargeted metabolomics and lipidomics uncovering the cardioprotective effects of Huanglian Jiedu Decoction on pathological cardiac hypertrophy and remodeling.

ETHNOPHARMACOLOGICAL RELEVANCE: As a classic herbal prescription, Huanglian Jiedu Decoction (HLJDD) exhibits positive effects against cardiac dysfunction. However, its cardioprotective effects and potential mechanism(s) of action still need to be systematically investigated. AIM OF THE STUDY: This study aimed to reveal the underlying therapeutic mechanism of HLJDD on transverse aortic constriction (TAC)-induced pathological cardiac hypertrophy and remodeling. MATERIALS AND METHODS: TAC-induced cardiac hypertrophy and remodeling mice model was established to evaluate the therapeutic effects of HLJDD. Serum untargeted metabolomics and lipidomic profiling were performed using ultra-performance liquid chromatography quadrupole-time-of-flight mass spectrometry coupled with multivariate statistical analyses. RESULTS: Oral administration of HLJDD (2.5 g/kg/day, 5.0 g/kg/day) significantly improved the heart morphology, enhanced the heart function, and alleviated the accumulation of fibrosis in the interstitial space and the infiltration of inflammatory cells in TAC-stimulated mice. Serum untargeted metabolomics analysis showed that significant alterations were observed in metabolic signatures between the TAC-model and sham group. Principal component analysis and orthogonal partial least-squares discriminant analysis screened 59 differential metabolic features and 13 metabolites were identified. The disturbed metabolic pathways in TAC group mainly related to lipid metabolism. Further serum lipidomic profiling showed that most lipids including cholesterol esters, ceramides, glycerides, fatty acids and phospholipids were decreased in TAC group and these alterations were reversed after HLJDD intervention. CONCLUSION: HLJDD alleviates TAC-induced pathological cardiac hypertrophy and remodeling, and its potential therapeutic mechanism involves the regulation of lipid metabolism.

Metabolomic and transcriptomic analyses of the anti-rheumatoid arthritis potential of xylopic acid in a bioinspired lipoprotein nanoformulation.

Xylopic acid (XA), a diterpene kaurene and the major active ingredient of the African spice Xylopia aethiopica (Annonaceae), is reported to possess anti-inflammatory and analgesic properties. Here, we investigated the therapeutic potential of XA for rheumatoid arthritis (RA), a debilitating autoimmune inflammatory disease characterized by joint damage, in the complete Freund's adjuvant (CFA)-induced arthritis model in rats. We synthesized bioinspired reconstituted high-density lipoprotein (rHDL) nanoparticles loaded with purified XA crystals (rHDL/XA) that passively accumulate in inflamed joints of CFA-induced arthritic rats. Treatment with rHDL/XA minimized mononuclear cell infiltration of CFA-induced arthritic sites and ameliorated disease burden. Metabolomic and transcriptomic analyses revealed that the major molecular pathways perturbed following CFA-induced arthritis correlated with amino acid and lipid metabolism, which were restored to normal states by rHDL/XA treatment. This work demonstrates the anti-RA potential of XA in a nanoformulation and uncovers its underlying therapeutic mechanisms at the transcript and metabolite levels.

Metabolomics identifying biomarkers of PM2.5 exposure for vulnerable population: based on a prospective cohort study.

Long-term exposure to particular matter (PM), especially fine PM (< 2.5 µm in the aerodynamic diameter, PM2.5), is associated with increased risk of cardiovascular disorders. This study aimed to evaluate the association between long-term exposure to PM2.5/PM10 and the metabolic change in the plasma. Specifically, using metabolomics, we sought to identify the biomarkers for the vulnerable subgroup to PM2.5 exposure. A total of 78 college student volunteers were recruited into this prospective cohort study. All participants received 8 rounds of physical examinations at twice quarterly. Air purifiers were placed in 40 of 78 participants' dormitories for 14 days. Before and after intervention, physical examinations were performed and the peripheral blood was collected. Plasma metabolomics was determined by ultra-performance liquid chromatography-mass spectrometry. During the follow-up, the average concentrations of PM2.5 and PM10 were 53 µg/m3 and 93 µg/m3, respectively. Totally, 42 and 120 differential metabolic features were detected for PM10 and PM2.5 exposure, respectively. In total, 25 differential metabolites were identified for PM2.5 exposure, most of which were phospholipids. No distinctive metabolites were found for PM10 exposure. A total of 6 differential metabolites (lysoPC (P-20:0), lysoPC (P-18:1(9z)), lysoPC (20:1), lysoPC (O-16:0), choline, and found 1,3-diphenylprop-2-en-1-one) were characterized and confirmed for sensitive individuals. Importantly, we found LysoPC (P-20:0) and LysoPC (P-18:1(9z)) changed significantly before and after air purifier intervention. Our results indicated that the phospholipid catabolism was involved in long-term PM2.5 exposure. LysoPC (P-20:0) and LysoPC (P-18:1(9z)) may be the biomarkers of PM2.5 exposure.

A mass spectrometry database for identification of saponins in plants.

Saponins constitute an important class of secondary metabolites of the plant kingdom. Here, we present a mass spectrometry-based database for rapid and easy identification of saponins henceforth referred to as saponin mass spectrometry database (SMSD). With a total of 4196 saponins, 214 of which were obtained from commercial sources. Through liquid chromatography-tandem high-resolution/mass spectrometry (HR/MS) analysis under negative ion mode, the fragmentation behavior for all parent fragment ions almost conformed to successive losses of sugar moieties, α-dissociation and McLafferty rearrangement of aglycones in high-energy collision induced dissociation. The saccharide moieties produced sugar fragment ions from m/z (monosaccharide) to m/z (polysaccharides). The parent and sugar fragment ions of other saponins were predicted using the above mentioned fragmentation pattern. The SMSD is freely accessible at http://47.92.73.208:8082/ or http://cpu-smsd.com (preferrably using google). It provides three search modes ("CLASSIFY", "SEARCH" and "METABOLITE"). Under the "CLASSIFY" function, saponins are classified with high predictive accuracies from all metabolites by establishment of logistic regression model through their mass data from HR/MS input as a csv file, where the first column is ID and the second column is mass. For the "SEARCH" function, saponins are searched against parent ions with certain mass tolerance in "MS Ion Search". Then, daughter ions with certain mass tolerance are input into "MS/MS Ion Search". The optimal candidates were screened out according to the match count and match rate values in comparison with fragment data in database. Additionally, another logistic regression model completely differentiated between parent and sugar fragment ions. This function designed in front web is conducive to search and recheck. With the "METABOLITE" function, saponins are searched using their common names, where both full and partial name searches are supported. With these modes, saponins of diverse chemical composition can be explored, grouped and identified with a high degree of predictive accuracy. This specialized database would aid in the identification of saponins in complex matrices particular in the study of traditional Chinese medicines or plant metabolomics.

Cerebrospinal fluid-based metabolomics to characterize different types of brain tumors.

BACKGROUND: Brain tumors cause significant morbidity and mortality due to rapid progression and high recurrence risks. Reliable biomarkers to improve diagnosis thereof are desirable. OBJECTIVE: This work aimed to identify panels of biomarkers for diagnostic purposes using cerebrospinal fluid (CSF)-based metabolomics. METHODS: A cohort of 163 histologically-proven patients with brain disorders was involved. Comprehensive CSF-based metabolomics was achieved by liquid chromatography-quadrupole time-of-flight spectrometric (LC-Q/TOF-MS) and multivariate statistical analyses. The diagnostic performance of the metabolic markers was evaluated using receiver operating characteristic curves. RESULTS: A total of 508 ion features were detected by the LC-Q/TOF-MS analysis, of which 27 metabolites were selected as diagnostic markers to discriminate different brain tumor types. The area under the curve (AUC) was 0.91 for lung adenocarcinoma patients with brain metastases (MBT) vs. lung adenocarcinoma patients without brain metastases (NMBT), 0.83 for primary central nervous system lymphoma (PCNSL) vs. secondary central nervous system involvement of systemic lymphoma (SCNSL), 0.77 for PCNSL vs. MBT, 0.87 for SCNSL vs. MBT, 0.86 for MBT vs. nontumorous brain diseases (NT), and 0.80 for PCNSL vs. NT. Perturbed metabolic pathways between the comparisons related mainly to amino acids and citrate metabolism. CONCLUSIONS: CSF-based metabolomics to a large extent reliably identifies significant metabolic differences between different brain tumors and shows great potential for diagnosis of brain tumors.

Serum-plasma matched metabolomics for comprehensive characterization of benign thyroid nodule and papillary thyroid carcinoma.

Metabolomics offers a noninvasive methodology to identify metabolic markers for pathogenesis and diagnosis of diseases. This work aimed to characterize circulating metabolic signatures of benign thyroid nodule (BTN) and papillary thyroid carcinoma (PTC) via serum-plasma matched metabolomics. A cohort of 1,540 serum-plasma matched samples and 114 tissues were obtained from healthy volunteers, BTN and PTC patients enrolled from 6 independent centers. Untargeted metabolomics was determined by liquid chromatography-quadrupole time-of-flight mass spectrometric and multivariate statistical analyses. The use of serum-plasma matched samples afforded a broad-scope detection of 1,570 metabolic features. Metabolic phenotypes revealed significant pattern differences for healthy versus BTN and healthy versus PTC. Perturbed metabolic pathways related mainly to amino acid and lipid metabolism. It is worth noting that, BTN and PTC showed no significant differences but rather overlap in circulating metabolic signatures, and this observation was replicated in all study centers. For differential diagnosis of healthy versus thyroid nodules (BTN + PTC), a panel of 6 metabolic markers, namely myo-inositol, α-N-phenylacetyl-L-glutamine, proline betaine, L-glutamic acid, LysoPC(18:0) and LysoPC(18:1) provided area under the curve of 97.68% in the discovery phase and predictive accuracies of 84.78-98.18% in the 4 validation centers. Taken together, serum-plasma matched metabolomics showed significant differences in circulating metabolites for healthy versus nodules but not for BTN versus PTC. Our results highlight the true metabolic nature of thyroid nodules, and potentially decrease overtreatment that exposes patients to unnecessary risks.

A simple and rapid fluorescent approach for flavonoids sensor based on gold nanoclusters.

The development of simple, easy-to-operate and real-time detection methods for the active ingredients in herbal medicines has aroused growing interest owing to their pivotal health benefits. In this study, a qualitative and quantitative detection method for the flavonoids was developed based on the specific interaction between flavonoids and bovine serum albumin (BSA). A fluorescent gold nanocluster was imbedded into the cavity enclosed in the tertiary structure of BSA, the fluorescence of which can be quenched by the flavonoids with fast response (<5 s). This decrease in fluorescence intensity of BSA-AuNCs as output signal enables the real-time visual inspection of flavonoids. We demonstrated that the present approach was capable of detecting quercetin in serum, plasma, and monitoring the content of flavonoids in proprietary Chinese medicine Rutin Tablets. BSA-AuNCs was the first fluorescent probe for the specific determination of active ingredients in herbal medicines. Hence the reported protein-AuNCs sensing platform can serve as a convenient detection strategy in pharmaceutical analysis.

Functional Metabolomics Characterizes a Key Role for N-Acetylneuraminic Acid in Coronary Artery Diseases.

BACKGROUND: As new biomarkers of coronary artery diseases (CAD) emerge via metabolomics, the underlying functional mechanisms remain to be elucidated. Functional metabolomics aims to translate metabolomics-derived biomarkers to disease mechanisms. METHODS: A cohort of 2324 patients who underwent coronary angiography from 4 independent centers was studied. A combination of ultra-performance liquid chromatography and quadrupole time-of-flight mass spectrometry in the negative ion mode was used for untargeted analysis of metabolites in plasma. Significant differential metabolites were identified by cross-comparisons with and within CAD types, including normal coronary artery, nonobstructvie coronary atherosclerosis, stable angina, unstable angina, and acute myocardial infarction. A tandem liquid chromatography-mass spectrometry-based approach using isotope-labeled standard addition was subsequently performed for targeted analysis of the metabolic marker N-acetylneuraminic acid (Neu5Ac). A functional metabolomics strategy was proposed to investigate the role of Neu5Ac in the progression of CAD by using in vitro and in vivo models. RESULTS: We identified a total of 36 differential metabolites, 35 of which were confirmed with reference compounds. Elevation of Neu5Ac was observed in plasma during CAD progression in center 1 (P=4.0e-64, n=2019) and replicated in 3 independent centers (n=305). The increased level of Neu5Ac in plasma was confirmed by accurate targeted quantification. Mechanistically, Neu5Ac was able to trigger myocardial injury in vitro and in vivo by activation of the Rho/Rho-associated coiled-coil containing protein kinase signaling pathway through binding to RhoA and Cdc42, but not Rac1. Silencing neuraminidase-1, the enzyme that regulates Neu5Ac generation, ameliorated oxygen-glucose deprivation-induced injury in cardiomyocytes and ligation/isoprenaline-induced myocardial ischemia injury in rats. Pharmacological inhibition of neuraminidase by anti-influenza drugs, oseltamivir and zanamivir, also protected cardiomyocytes and the heart from myocardial injury. CONCLUSIONS: Functional metabolomics identified a key role for Neu5Ac in acute myocardial infarction, and targeting neuraminidase-1 may represent an unrecognized therapeutic intervention for CAD.

Regioselective Synthesis of Carbonyl-Containing Alkyl Chlorides via Silver-Catalyzed Ring-Opening Chlorination of Cycloalkanols.

A novel and regioselective approach to carbonyl-containing alkyl chlorides via silver-catalyzed ring-opening chlorination of cycloalkanols is reported. Concurrent C(sp(3))-C(sp(3)) bond cleavage and C(sp(3))-Cl bond formation efficiently occur with good yields under mild conditions, and the chlorinated products are readily transformed into other useful synthetic intermediates and drugs. The reaction features complete regioselectivity, high efficiency, and excellent practicality.