Regulation Of Amino Acid Metabolism Research Articles

Improved heat tolerance in creeping bentgrass by γ-aminobutyric acid, proline, and inorganic nitrogen associated with differential regulation of amino acid metabolism

Plant defense against heat stress involves adjustments in amino acid metabolism. The objective of this study was to identify major amino acids and associated metabolic pathways differentially regulated by γ-aminobutyric acid (GABA) and proline that may contribute to augmentation of heat tolerance in cool-season grass species. Creeping bentgrass (Agrostis stolonifera L. cv. ‘Penncross’) was exposed to non-stress (22/18 °C, day/night) or heat stress (35/30 °C, day/night) conditions for 35 d in controlled-environment growth chambers. Non-stressed and heat-stressed plants were foliar-sprayed with water (untreated control), GABA, proline, or ammonium nitrate (N) as a nitrogen source control. Under heat stress, foliar application of GABA, proline, or N significantly increased turf quality and leaf chlorophyll content compared to untreated control plants. N application had nutritional effects, resulting in increases in the content of all amino acids under heat stress. Application of GABA under heat stress significantly increased endogenous content of glutamic acid, GABA, and threonine. Plants treated with proline under heat stress had significantly higher endogenous levels of proline, GABA, glutamic acid, aspartic acid, lysine, isoleucine, leucine, valine, serine, alanine, threonine, and tryptophan compared to untreated controls. The improved heat tolerance in creeping bentgrass pathway by GABA was mainly associated with regulation of amino acid metabolism in the GABA shunt and oxaloacetate pathways. Proline-enhanced heat tolerance involved the regulation of five metabolic pathways (GABA shunt, oxaloacetate, 3-phosphoglycerate, secondary metabolism, and pyruvate). GABA and proline, as well as their responsive amino acids could be used as biomarkers to improve heat tolerance in cool-season grass species.

Cepharanthine inhibits hepatocellular carcinoma cell growth and proliferation by regulating amino acid metabolism and suppresses tumorigenesis in vivo.

Cepharanthine (CEP), a natural compound extracted from Stephania cepharantha Hayata, has been found to have the potential to treat a variety of tumors in recent years. This study aims to evaluate the anti-hepatocellular carcinoma (HCC) effect of CEP and determine its in-depth mechanism. In this study, Hep3B and HCCLM3 cells were selected to evaluate the antitumor effects of CEP in vitro, whereas tumor xenograft in nude mice was performed to make in vivo anti-tumor assessment. RNA-sequence (RNA-seq) was used to identify possible molecular targets and pathways. Further, gas chromatography mass spectrometry (GC-MS) was performed to assess the differential metabolites involved in mediating the effect of CEP on the HCC cell line. Our results showed that CEP treatment resulted in the dose-dependent inhibition of cell viability, migration, and proliferation and could also induce apoptosis in HCC cells. RNA-seq following CEP treatment identified 168 differentially expressed genes (DEGs), which were highly enriched in metabolism-associated pathways. In addition, CEP down-regulated many metabolites through the amino acid metabolism pathway. In vivo experiment showed that CEP significantly suppressed tumor growth. Our results indicate that CEP has significant antitumor effects and has the potential to be a candidate drug for HCC treatment.

Effects of Ni (II) p-hydroxybenzoate with caffeine on metabolic, antioxidant and biochemical parameters of model insect Galleria mellonella L. (Lepidoptera: Pyralidae)

Many insecticides used against pests cause environmental pollution. Therefore, it is very important to develop new alternative strategies to toxic insecticides. In this study, the physiological and biochemical effects of Ni (II) p-hydroxybenzoate with caffeine on the model insect Galleria mellonella were investigated. In the present study, transferase enzyme activities such as alanine transferase, aspartate transferase and gamma-glutamyl transferase, which regulate amino acid metabolism, were altered in hemolymph of G. mellonella larvae exposed to Ni (II) p-hydroxybenzoate with caffeine. In addition, the activities of metabolic enzymes such as creatine kinase, lactate dehydrogenase, and amylase increased in hemolymph of G. mellonella larvae. Amounts of the biochemical parameters such as uric acid, bilirubin, albumin, cholesterol, and total protein were increased exposed to Ni (II) p-hydroxybenzoate with caffeine. Based on these results, we can suggest a well-adjusted Ni (II) p-hydroxybenzoate with caffeine concentrations as a potential alternative chemical for pest control. Key words:

A low molecular weight brown algae Laminaria japonica glycan modulation of gut microbiota and body weight in mice.

Brown algae glycan from Laminaria japonica (LJNP) is a heterogeneous glycan with two apparent molecular weights of 1.1 and 37.3 kDa, and is mainly composed of α β-glucan and a few fucosyl residues. To explore the regulation of gut microbiota and the host, LJNP and 2'-fucosyllactose (2'FL) were compared to investigate their effect on mice via oral administration. Using metagenomic and metabolomic analyses, we found that 2'FL mainly relied on Adlercreutzia equolifaciens and Akkermansia muciniphila to improve gut amino acid and bile acid metabolism, whereas LJNP mainly drove Bacteroides vulgatus and Bacteroides uniformis to regulate gut amino acid metabolism and glycometabolism. Moreover, LJNP showed a weight loss effect and better protection of the intestinal barrier than 2'FL. We further employed LJNP and 2'FL on a germ-free mice model. Interestingly, the body weight management was not microbiome mediated. This study showed that LJNP can ameliorate the intestinal barrier through modulation of the gut microbiota, maintain the blood glucose level, and regulate body weight and the antioxidant function. Although the benefits of LJNP on host health were partly revealed, mechanisms such as the weight loss effect require further study.

1H NMR-based dynamic metabolomics delineates the therapeutic effects of Shenfu injection on laparoscopic hysterectomy.

To explore the effect and mechanism of Shenfu Injection on serum metabolomics in laparoscopic hysterectomy.1.5 mL/kg Shenfu injection was added to inject 200 mL of normal saline after the patients who entered the standard were admitted to the operating room. NMR metabolomics were performed at each time point before anesthesia (T0), immediately after pneumoperitoneum (T1), and at the end of surgery (T2).Multivariate trajectory analysis showed that SFI treatment could make laparoscopic hysterectomy interfere with the recovery of plasma metabolites to normal metabolic state, with a time-dependent trend. In addition, the key metabolic changes of laparoscopic hysterectomy at different stages of SFI treatment involve energy metabolism, oxidative stress response, amino acid metabolism, and pyruvate metabolism. Especially, the important role of SFI in the treatment of laparoscopic hysterectomy is antioxidant capacity. The results show that SFI can be used as a potential drug for laparoscopic hysterectomy.The current findings provided, for the first time, sound evidence of the protective effects of SFI on laparoscopic hysterectomy from both biochemical and metabolomics perspectives. The mechanisms of SFI could be related to regulating amino acid metabolism, pyruvate metabolism, and energy metabolism. The present study lays an important foundation for further research and for the broad clinical application of SFI.

Abstract IA02: Regulating amino acid metabolism can improve response to immunotherapy

Abstract Aberrant expression of urea cycle enzymes occurs in multiple types of cancer. We have previously demonstrated that the urea cycle enzyme ASS1 is downregulated in different tumor types to increase the availability of its substrate aspartate for pyrimidine synthesis, supporting cell proliferation. Therapeutically, we demonstrated that high pyrimidine to purine ratio improves response to immunotherapy. Interestingly, in several prevalent types of cancer ASS1 expression is upregulated for a yet unknown metabolic benefit that associates with poor patients’ prognosis. We now find that ASS1 expression in cancer provides a survival advantage in nutrient deficiency states by generating NO that activates gluconeogenesis. The increase in gluconeogenic flux increases serine levels and leads to a nucleotide imbalance promoting pyrimidine to purine transversion mutations. Consequently, cancers with high ASS1 expression are less immunogenic. Reversing the nucleotide imbalance to favor pyrimidines leads to better response to immunotherapy. Our data establish ASS1 expression as a metabolic survival mechanism under nutrient deprivation that may also serve as a strong determinant of the immune response. Importantly, our findings suggest that we can metabolically regulate tumor mutations to improve patients’ responsiveness to immunotherapy. Citation Format: Ayelet Erez, Eytan Ruppin. Regulating amino acid metabolism can improve response to immunotherapy [abstract]. In: Abstracts: AACR Special Virtual Conference on Epigenetics and Metabolism; October 15-16, 2020; 2020 Oct 15-16. Philadelphia (PA): AACR; Cancer Res 2020;80(23 Suppl):Abstract nr IA02.

An investigation of the antidepressant-like effect of Jiaotaiwan in rats by nontargeted metabolomics based on ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry.

Depression is a mental disorder characterized by persistent unhappiness, lack of interest, with cognitive and sleep disorders. Jiaotaiwan is a traditional Chinese medicine for the treatment of insomnia and depressive-like symptoms. In this study, the major chemical components in Jiaotaiwan were qualitatively analyzed using ultra high performance liquid chromatography quadrupole time-of-flight mass spectrometry, and a model of depression in rats was subsequently established with chronic unpredictable mild stress followed by Jiaotaiwan intervention. Next, the metabolic profile of rat serum samples was analyzed using nontargeted metabolomics, wherein changes in the metabolites in serum samples before and after Jiaotaiwan administration were measured by multiple statistical approaches. Principal component analysis and partial least squares discriminant analysis indicated that the Jiaotaiwan treatment improved the metabolic phenotype depression. Moreover, the heatmap analysis identified the most important ten biomarkers involved in depression. According to the pathway analysis, the therapeutic effect of Jiaotaiwan on depression may involve the regulation of amino acid metabolism, glycerophospholipid metabolism, and energy metabolism. These findings help us understand the pathogenesis of depression in-depth, and discover targets for clinical diagnosis and treatment. And it also lays a foundation for the use of Jiaotaiwan as an antidepressant agent.

Plectin is a regulator of prostate cancer growth and metastasis.

Prostate cancer is responsible for over 30,000 US deaths annually, attributed largely to incurable metastatic disease. Here, we demonstrate that high levels of plectin are associated with localized and metastatic human prostate cancer when compared to benign prostate tissues. Knock-down of plectin inhibits prostate cancer cell growth and colony formation in vitro, and growth of prostate cancer xenografts in vivo. Plectin knock-down further impairs aggressive and invasive cellular behavior assessed by migration, invasion, and wound healing in vitro. Consistently, plectin knock-down cells have impaired metastatic colonization to distant sites including liver, lung, kidney, bone, and genitourinary system. Plectin knock-down inhibited number of metastases per organ, as well as decreased overall metastatic burden. To gain insights into the role of plectin in prostate cancer growth and metastasis, we performed proteomic analysis of prostate cancer plectin knock-down xenograft tissues. Gene set enrichment analysis shows an increase in levels of proteins involved with extracellular matrix and laminin interactions, and a decrease in levels of proteins regulating amino acid metabolism, cytoskeletal proteins, and cellular response to stress. Collectively these findings demonstrate that plectin is an important regulator of prostate cancer cell growth and metastasis.

Evaluating the impact of methionine-enriched diets in the liver of European seabass through label-free shotgun proteomics

Plant protein sources play an essential role in aquaculture by reducing the use of fish meal to sustainable levels, although further supplementation is needed to fulfill fish nutritional requirements. This work addressed fish growth performance and proteome changes to dietary methionine in European seabass juveniles. A dose-dependent response to methionine (Met) was observed on fish growth consistent with proteomic analyses, suggesting Met requirement ≥0.9% (w/w). Fish fed at 0.77% (w/w) exhibited reduced growth and an enrichment in proteins involved in cellular homeostasis. Proteomics data suggest an optimal nutritional status at 1.36% Met (w/w), together with putative beneficial effects on the immune system up to 1.66% Met (w/w). The response to dietary Met involved the convergence of different metabolic and signalling pathways implicated in cell growth and immune response e.g., mTOR, Hedgehog or the T Cell receptor signalling, coupled with a fine-tuning regulation of amino acid metabolism and translation.

Effects of Ibrutinib on Metabolic Alterations and Micro-Environmental Signalling in Chronic Lymphocytic Leukaemia

Introduction. Altered metabolism is one of the hallmarks of cancer. CLL cells circulate between peripheral blood (PB) and lymph nodes (LN) which necessitates high metabolic plasticity. In LN, CLL cells receive proliferative and pro-survival signals from surrounding cells, and become metabolically activated. However, detailed insight into the altered metabolism of LN CLL and how this may be related to therapeutic responses is lacking. As it is technically difficult to obtain direct insight into CLL LN metabolism, we have applied a two-tiered strategy. By using PB samples taken from patients before/after treatment with the Bruton's tyrosine kinase (BTK) inhibitor ibrutinib (IBR), which drives CLL cells out of the LN, combined with in vitro re-stimulation of TME signals, we indirectly mapped the metabolism of CLL in their TME, as well as the effects of IBR treatment. We hypothesized that the overlapping/distinct metabolites affected by IBR and in vitro stimulations would reflect the actual CLL metabolism in LN. Methods. PB samples were obtained from 7 CLL patients before or after 3 months of ibrutinib treatment. These paired samples were in vitro stimulated via CD40 and B cell receptor (BCR), which are potential key signals within the tumour microenvironment (TME). Seahorse extracellular flux (ECF) analyses, expression of activation markers (CD95, pS6 by FACS), RNA was isolated for expression of Myc (major driver of metabolic reprogramming) and its target genes, and metabolomics by mass-spec was performed. Results. ECF analyses showed that in comparison to BCR stimulated PB CLL cells, stimulation by CD40 resulted in a high increase of oxygen consumption rate (OCR) and extracellular acidification rate (ECAR). A prominent effect on OXPHOS and glycolytic activity was confirmed in direct LN samples, and indirectly by marker analyses in LN emigrants using CXCR4/CD5 staining [1]. Subsequent metabolomics analyses showed that metabolic reprogramming following CD40 or BCR stimulation revealed both shared and distinct responses. The affected metabolic pathways, predicted by significantly changed metabolites, were compared in a pairwise fashion; upregulated by CD40 and BCR but downregulated by IBR, respectively. The results demonstrated 5 upregulated pre-defined pathways (KEGG) by both CD40 and BCR triggering: purine metabolism, Warburg effect, lysine degradation, glucose-alanine cycle and glutamate metabolism. In contrast, the following pathways indicated the two signals had distinct functions on regulating metabolism: CD40 signalling mostly regulates amino acid metabolism, tricarboxylic acid cycle (TCA) and mitochondrial metabolism related to oxidative phosphorylation (OXPHOS) and energy production. BCR signalling mainly involves glucose and glycerol metabolism, which are usually related to biosynthesis. CLL cells from IBR-treated patients showed enhanced BCR responsiveness, in line with the increased in surface IgM expression upon IBR [2]. In contrast, IBR treatment suppressed in vitro CD40 activation, which was accompanied by a lower CD40 expression. Metabolomics analyses also demonstrated that CD40 responses decreased but BCR response increased after IBR. Additionally, analyses of Myc and its target genes showed that they are induced after BCR as well as CD40 stimulation. Effects of IBR on Myc (target) expression were variable for BCR and reduced for CD40 stimulation. Conclusions. In vivo IBR treatment suppresses CD40 expression and activation and enhances BCR responsiveness. Metabolic changes of CLL in LN are recapitulated by these two signals, while IBR treatment shows opposite effects, together providing indirect insight into the LN metabolism. In LN, CD40 may play a prominent role to enhance most of the key metabolic pathways, particularly OXPHOS. This is the first study to describe the metabolic network of CLL cells in LN, and the long-term effects of IBR may yield new clues to therapy response and resistance.

Novel regulation of cardiac branched-chain amino acid metabolism through AMP deaminase: a possible therapeutic target for diabetic cardiomyopathy

Abstract Background Dysregulation of branched-chain amino acid (BCAA) metabolism has been shown to be associated with type 2 diabetes mellitus (T2DM) and heart failure. BCAA reportedly protects cells from fatty acid-induced mitochondrial injury via sequestration of fatty acids in intracellular lipid droplets from mitochondria. We previously reported that up-regulation of AMP deaminase 3 (AMPD3) impairs cardiac energetics in T2DM hearts, and AMPD3 was recently shown to participate in regulation of amino acid metabolism in skeletal muscle. Purpose We hypothesized that AMPD3 regulates cardiac amino acid metabolism by interaction with branched-chain α-ketoacid dehydrogenase (BCKDH) complex and that cardioprotective effect of sodium glucose cotransporter 2 inhibitors is mediated by modification of BCAA metabolism in diabetic cardiomyocytes. Methods and results Proteomic analyses of immunoprecipitates with an anti-AMPD3 antibody in rat hearts revealed that AMPD3 interacted with the E1α component of BCKDH complex. Whereas BCKDH has been reported to localize in mitochondria matrix as a rate-limiting enzyme for BCAA catabolism, immunoblotting using subcellular fractions revealed that BCKDH E1α is present in cytosol and endoplasmic reticulum as well. AMPD3-BCKDH E1α interaction was decreased by 68% in T2DM rats (OLETF) compared to that in control rats (LETO), and significant accumulation of BCAAs was observed in OLETF hearts (317±30 vs. 213±16 nmol/g). Survival rate at 48 hours after myocardial infarction (MI) was significantly lower in OLETF than in LETO (40% vs 84%). Empagliflozin treatment (10 mg/kg/day, 14 days) before MI improved the survival rate in OLETF to 70%, increased BCAAs as the top of 92 detected metabolites (791±187 nmol/g) and significantly preserved tissue ATP in the non-MI remote region. Electron microscopy showed a significantly higher prevalence of myocardium lipid droplets in OLETF, which was further increased by empagliflozin. Conclusions Results of the present analyses support the hypotheses that conversion of BCAA-derived branched-chain α-ketoacid to branched-chain acyl-CoA is suppressed by reduced AMPD3-BCKDH interaction in the myocardium of T2DM and that empagliflozin induces compensation of the dysregulated cardiac BCAA metabolism by augmentation of BCAA influx and promotion of fatty acid sequestration in intracellular lipid droplets. Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): Boehringer Ingelheim

Study on anti-osteoporosis effect of Eucommiae Cortex based on GC-MS metabonomics

Based on GC-MS metabolomics and biochemical index analysis, the mechanism of bone mass loss in osteoporosis and the evaluation of anti-osteoporosis in Eucommiae Cortex were studied. The OVX rats model was established by bilateral ovariectomized. The routine indexes such as BMC, BMD, BGP and TRAP5 b were determined. The GC-MS technique was used to analyze the metabolism profile of serum samples between the control group, model group and medicine group, and multiple statistical analysis methods including principal component analysis(PCA), partial least squares-linear discriminant analysis(PLS-LDA) and subwindow rearrangement analysis(SPA) were used to screen and identify biomarkers. Five metabolites were selected as potential biomarkers, glycine, lysine, tryptophan, docosahexaenoic acid and glucose. Except for the significant increase of tryptophan in serum of OVX rats, the other four metabolites were significantly decreased. Moreover, the five biomarkers of the medicine group had a trend of returning to rats in control group. The significantly altered metabolite levels indicated that Eucommiae Cortex may relieve the symptoms of osteoporosis by regulating amino acid metabolism and oxidative stress.

Atherosclerosis Linked to Aberrant Amino Acid Metabolism and Immunosuppressive Amino Acid Catabolizing Enzymes.

Cardiovascular disease is the leading global health concern and responsible for more deaths worldwide than any other type of disorder. Atherosclerosis is a chronic inflammatory disease in the arterial wall, which underpins several types of cardiovascular disease. It has emerged that a strong relationship exists between alterations in amino acid (AA) metabolism and the development of atherosclerosis. Recent studies have reported positive correlations between levels of branched-chain amino acids (BCAAs) such as leucine, valine, and isoleucine in plasma and the occurrence of metabolic disturbances. Elevated serum levels of BCAAs indicate a high cardiometabolic risk. Thus, BCAAs may also impact atherosclerosis prevention and offer a novel therapeutic strategy for specific individuals at risk of coronary events. The metabolism of AAs, such as L-arginine, homoarginine, and L-tryptophan, is recognized as a critical regulator of vascular homeostasis. Dietary intake of homoarginine, taurine, and glycine can improve atherosclerosis by endothelium remodeling. Available data also suggest that the regulation of AA metabolism by indoleamine 2,3-dioxygenase (IDO) and arginases 1 and 2 are mediated through various immunological signals and that immunosuppressive AA metabolizing enzymes are promising therapeutic targets against atherosclerosis. Further clinical studies and basic studies that make use of animal models are required. Here we review recent data examining links between AA metabolism and the development of atherosclerosis.

Glucagon acutely regulates hepatic amino acid catabolism and the effect may be disturbed by steatosis

ObjectiveGlucagon is well known to regulate blood glucose but may be equally important for amino acid metabolism. Plasma levels of amino acids are regulated by glucagon-dependent mechanism(s), while amino acids stimulate glucagon secretion from alpha cells, completing the recently described liver-alpha cell axis. The mechanisms underlying the cycle and the possible impact of hepatic steatosis are unclear. MethodsWe assessed amino acid clearance in vivo in mice treated with a glucagon receptor antagonist (GRA), transgenic mice with 95% reduction in alpha cells, and mice with hepatic steatosis. In addition, we evaluated urea formation in primary hepatocytes from ob/ob mice and humans, and we studied acute metabolic effects of glucagon in perfused rat livers. We also performed RNA sequencing on livers from glucagon receptor knock-out mice and mice with hepatic steatosis. Finally, we measured individual plasma amino acids and glucagon in healthy controls and in two independent cohorts of patients with biopsy-verified non-alcoholic fatty liver disease (NAFLD). ResultsAmino acid clearance was reduced in mice treated with GRA and mice lacking endogenous glucagon (loss of alpha cells) concomitantly with reduced production of urea. Glucagon administration markedly changed the secretion of rat liver metabolites and within minutes increased urea formation in mice, in perfused rat liver, and in primary human hepatocytes. Transcriptomic analyses revealed that three genes responsible for amino acid catabolism (Cps1, Slc7a2, and Slc38a2) were downregulated both in mice with hepatic steatosis and in mice with deletion of the glucagon receptor. Cultured ob/ob hepatocytes produced less urea upon stimulation with mixed amino acids, and amino acid clearance was lower in mice with hepatic steatosis. Glucagon-induced ureagenesis was impaired in perfused rat livers with hepatic steatosis. Patients with NAFLD had hyperglucagonemia and increased levels of glucagonotropic amino acids, including alanine in particular. Both glucagon and alanine levels were reduced after diet-induced reduction in Homeostatic Model Assessment for Insulin Resistance (HOMA-IR, a marker of hepatic steatosis). ConclusionsGlucagon regulates amino acid metabolism both non-transcriptionally and transcriptionally. Hepatic steatosis may impair glucagon-dependent enhancement of amino acid catabolism.

Involvement of subdomain II in the recognition of acetyl-CoA revealed by the crystal structure of homocitrate synthase from Sulfolobus acidocaldarius.

Homocitrate synthase (HCS) catalyzes the aldol condensation of α-ketoglutarate and acetyl coenzyme A to form homocitrate, which is the first committed step of lysine biosynthesis through the α-aminoadipate pathway in yeast, fungi, and some prokaryotes. We determined the crystal structure of a truncated form of HCS from a hyperthermophilic acidophilic archaeon, Sulfolobus acidocaldarius, which lacks the RAM (Regulation of amino acid metabolism) domain at the C terminus serving as the regulatory domain for the feedback inhibition by lysine, in complex with α-ketoglutarate, Mg2+ , and CoA. This structure coupled with mutational analysis revealed that a subdomain, subdomain II, connecting the N-terminal catalytic domain and C-terminal RAM domain is involved in the recognition of acetyl-CoA. This is the first structural evidence of the function of subdomain II in the related enzyme family, which will lead to a better understanding of the catalytic mechanism of HCS. DATABASES: Structural data are available in the RCSB PDB database under the accession number 6KTQ.

Endogenous metabolites involving effects of moxibustion on injured gastric mucosal tissue in rats with stomach heat or cold syndrome based on nuclear magnetic resonance spectroscopy

To investigate the profile of metabolites of gastric mucosa involving the effectiveness of moxibustion in the treatment of syndromes of stomach heat (SH) and stomach cold (SC) by 1H-nuclear magnetic resonance (1H-NMR) spectroscopy in rats, so as to reveal its mechanisms underlying improvement of gastric disorders. Male SD rats were randomly divided into control, SH-model, SC-model, SH-moxibustion and SC-moxibustion groups (n＝6 rats/group). The SH-model and SC-model were established by gavage of pepper liquid plus ethanol, and ice water plus NaOH, respectively. Moxibustion was applied to bilateral "Zusanli" (ST36) and "Liangmen"(ST21) for 20 min, once daily for 7days. Histopathological changes of the gastric tissue were observed by H．E. staining. Differential metabolites in the gastric mucosal tissue were detected and the relevant metabolic pathways analyzed by using 1H-NMR, pattern recognition method，and online MetPA (http: //www.metaboanalyst.ca). Compared with the control group, the body mass was decreased significantly from the 4th to 14th day after modeling (P<0.05，P<0.01). After the treatment, the body mass was obviously increased from the 10th day on in both SH-EA and SC-EA groups relevant to the SH and SC model group, respectively (P<0.05，P<0.01). H．E. staining showed severe damage of the columnar epithelial structure of the gastric mucosa and inflammatory cell infiltration in the SH group, and inflammatory cell infiltration in the SC model group, which were relatively milder in both moxibustion groups. 1H-NMR analysis displayed a total of 16 potential biomarkers in the injured gastric mucosa of SH syndrome and 14 biomarkers for the SC syndrome after mode-ling, and 13 metabolites related to SH moxibustion and 8 metabolites related to SC moxibustion after moxibustion interventions, respectively. After moxibustion, among the 13 differential metabolites of the SH syndrome, the effectively up-regulated candidates were isoleucine, creatinine, choline and lactate (P<0.05), and the down-regulated ones were choline phosphate, glycine, alanine, urine pyrimidine, tyrosine, phenylalanine, hypoxanthine, adenosine and nicotinamide (P<0.05). Among the 8 metabolites related to the SC syndrome, creatinine, ethanolamine, choline, adenosine and nicotinamide were markedly increased (P<0.05), and glycine, creatine phosphate and tyrosine remarkably decreased in their levels after moxibustion (P<0.05). MetPA showed that moxibustion could regulate 10 metabolic pathways for SH syndrome and 7 metabolic pathways for SC syndrome. Metabolites and metabolic pathways are mainly involved in functions of amino acid metabolism, energy metabolism and inflammatory response. The idea of "moxibustion could be used for heat syndrome" has metabolic substance basis, and its efficacy in repairing the injured gastric mucosa involves regulation of amino acid metabolism, energy balance and inflammation response, and moxibustion for SH and SC syndromes has both generality and specificity in regulating metabolic activities.

Transcriptional regulation of amino acid metabolism in response to nitrogen deficiency and nitrogen forms in tea plant root (Camellia sinensis L.)

Free amino acids, including theanine, glutamine and glutamate, contribute greatly to the pleasant taste and multiple health benefits of tea. Amino acids in tea plants are mainly synthesized in roots and transported to new shoots, which are significantly affected by nitrogen (N) level and forms. However, the regulatory amino acid metabolism genes have not been systemically identified in tea plants. Here, we investigated the dynamic changes of free amino acid contents in response to N deficiency and forms in tea plant roots, and systemically identified the genes associated amino acid contents in individual metabolism pathways. Our results showed that glutamate-derived amino acids are the most dynamic in response to various forms of N and N deficiency. We then performed transcriptomic analyses of roots treated with N deficiency and various forms of N, and differentially expressed amino acid metabolic genes in each pathway were identified. The analyses on expression patterns and transcriptional responses of metabolic genes to N treatments provided novel insights for the molecular basis of high accumulation of theanine in tea plant root. These analyses also identified potential regulatory genes in dynamic amino acid metabolism in tea plant root. Furthermore, our findings indicated that the dynamic expression levels of CsGDH, CsAlaDC, CsAspAT, CsSDH, CsPAL, CsSHMT were highly correlated with changes of amino acid contents in their corresponding pathways. Herein, this study provides comprehensive insights into transcriptional regulation of amino acid metabolism in response to nitrogen deficiency and nitrogen forms in tea plant root.

Specific Eco-evolutionary Contexts in the Mouse Gut Reveal Escherichia coli Metabolic Versatility

Members of the gut microbiota are thought to experience strong competition for nutrients. However, how such competition shapes their evolutionary dynamics and depends on intra- and interspecies interactions is poorly understood. Here, we test the hypothesis that Escherichia coli evolution in the mouse gut is more predictable across hosts in the absence of interspecies competition than in the presence of other microbial species. In support, we observed that lrp, a gene encoding a global regulator of amino acid metabolism, was repeatedly selected in germ-free mice 2weeks after mono-colonization by this bacterium. We established that this specific genetic adaptation increased E.coli's ability to compete for amino acids, and analysis of gut metabolites identified serine and threonine as the metabolites preferentially consumed by E.coli in the mono-colonized mouse gut. Preference for serine consumption was further supported by testing a set of mutants that showed loss of advantage of an lrp mutant impaired in serine metabolism invitro and invivo. Remarkably, the presence of a single additional member of the microbiota, Blautia coccoides, was sufficient to alter the gut metabolome and, consequently, the evolutionary path of E.coli. In this environment, the fitness advantage of the lrp mutant bacteria is lost, and mutations in genes involved in anaerobic respiration were selected instead, recapitulating the eco-evolutionary context from mice with a complex microbiota. Together, these results highlight the metabolic plasticity and evolutionary versatility of E.coli, tailored to the specific ecology it experiences in the gut.

Effects of Bacillus velezensis FKM10 for Promoting the Growth of Malus hupehensis Rehd. and Inhibiting Fusarium verticillioides.

Bacillus velezensis is a novel species of Bacillus that has been widely investigated and used because of its direct or indirect growth improvement effect for many plants. B. velezensis FKM10 was previously isolated from rhizosphere soil of apple trees and shows potential as a plant growth-promoting and biocontrol bacterium. In this study, strain FKM10 was verified to inhibit some fungal pathogens of soil-borne plant diseases, produce siderophores to absorb ferric iron for plants, and degrade proteins. Pot experiments showed that the application of strain FKM10 could directly promote the growth of Malus hupehensis Rehd. by increasing biomass, promoting the absorption of nutrients, improving soil fertility, changing the soil microbial community structure, and reducing fungal diversity. The results of this study provided a basis for using strain FKM10 to improve crop yield and overcome diseases of plants. The mechanism of strain FKM10 to control the phytopathogenic fungus Fusarium verticillioides was studied by interoperation with RNA sequencing. Strain FKM10 can destroy the cell wall and cell membrane of F. verticillioides. The secretion of glucosidases, such as β-glucanase, might be one of the causes of the destruction of the fungal cell wall. The regulation of amino acid metabolism might also play an important role in the antibacterial process of strain FKM10. During the antibacterial process, strain FKM10 attacks F. verticillioides and strain FKM10 itself is also affected: the expression of spores is increased, the number of viable cells is decreased, and the ribonucleoprotein complex and flagellar assembly-related genes are downregulated. The results of this study indicate that both strain FKM10 and F. verticillioides have mutually inhibitory activities in a liquid environment. Comparative genome analysis of B. velezensis FKM10 reveals that the general features of their genomes are similar overall and contain the core genome for this species. The results of this study further reveal that B. velezensis can also serve as a basis for developing new biocontrol agents or microbial fertilizers.

Early galactooligosaccharide intervention alters the metabolic profile, improves the antioxidant capacity of mitochondria and activates the AMPK/Nrf2 signaling pathway in suckling piglet liver.

The suckling stage is a critical window time for the development of human and animal neonates. Our previous study found that an early-life galactooligosaccharide (GOS) intervention could improve the growth status of suckling piglets; however, the difference in the metabolic status between different treatment groups still remains unclear. In the present study, sixty neonatal piglets were used to investigate the effects of early-life GOS intervention on the hepatic metabolic profiles of piglets. In the first week after birth, the piglets in the GOS and control (CON) groups were fed with GOS solution (10 mL for 1 g per kg body weight per day) and physiological saline, respectively. On days 8 and 21, six piglets from each group were euthanized for sampling. Compared with the CON piglets, the GOS piglets showed a lower total serum cholesterol concentration on day 8, but a higher concentration of serum HDL-C and albumin on day 21. Principal component analysis and partial least-squares discriminant analysis showed a dramatic difference in the composition of hepatic metabolic profiles between the two groups. The GOS intervention mainly affected the lipid and amino acid metabolism of the piglets. Meanwhile, the mRNA levels of CPT-1 and PCG1α increased in the GOS piglets' liver. Additionally, with the accumulation of antioxidant-related metabolites in the GOS piglet liver, the hepatic mitochondrial antioxidant capacity increased, and the phosphorylation of AMP-activated protein kinase and the protein expression levels of nuclear factor-erythroid-2-related factor 2 and heme oxygenase-1 were also upregulated in the liver. In conclusion, our findings provide new insights into the effects of galactooligosaccharides on the growth of suckling piglets.