Phenylalanine Biosynthesis Research Articles

A pseudo-targeted metabolomics for discovery of potential biomarkers of cardiac hypertrophy in rats

Cardiac hypertrophy (CH) is one of the stages in the occurrence and development of severe cardiovascular diseases, and exploring its biomarkers is beneficial for delaying the progression of severe cardiovascular diseases. In this research, we established a comprehensive and highly efficient pseudotargeted metabolomics method, which demonstrated a superior capacity to identify differential metabolites when compared to traditionaluntargeted metabolomics. The intra/inter-day precision and reproducibility results proved the method is reliable and precise. The established method was then applied to seek the potential differentiated metabolic biomarkers of cardiac hypertrophy (CH) rats, and oxylipins, phosphorylcholine (PC), lysophosphatidylcholine (LysoPC), lysophosphatidylethanolamine (LysoPE), Krebs cycle intermediates, carnitines, amino acids, and bile acids were disclosed to be the possible differentiate components. Their metabolic pathway analysis revealed that the potential metabolic alterations in CH rats were mainly associated with phenylalanine, tyrosine and tryptophan biosynthesis, phenylalanine metabolism, arachidonic acid metabolism, citrate cycle, glyoxylate and dicarboxylate metabolism, and tyrosine metabolism. In sum, this research provided a comprehensiveand reliable LC-MS/MS MRM platform for pseudo-targeted metabolomics investigation of disease condition, and some interesting potential biomarkers were disclosed for CH, which merit further exploration in the future.

Applying GC-MS based serum metabolomic profiling to characterize two traditional Chinese medicine subtypes of diabetic foot gangrene.

Traditional Chinese medicine (TCM) has a long history and particular advantages in the diagnosis and treatment of diabetic foot gangrene (DFG). Patients with DFG are mainly divided into two subtypes, tendon lesion with edema (GT) and ischemic lesion without edema (GI), which are suitable for different medical strategies. Metabolomics has special significance in unravelling the complexities of multifactorial and multisystemic disorders. This study acquired the serum metabolomic profiles of two traditional Chinese medicine subtypes of DFG to explore potential molecular evidence for subtype characterization, which may contribute to the personalized treatment of DFG. A total of 70 participants were recruited, including 20 with DM and 50 with DFG (20 with GI and 30 with GT). Conventional gas chromatography-mass spectrometry (GC-MS) followed by orthogonal partial least-squares discriminant analysis (OPLS-DA) were used as untargeted metabolomics approaches to explore the serum metabolomic profiles. Kyoto encyclopedia of genes and genomes (KEGG) and MetaboAnalyst were used to identify the related metabolic pathways. Compared with DM patients, the levels of 14 metabolites were altered in the DFG group, which were also belonged to the differential metabolites of GI (13) and GT (7) subtypes, respectively. Among these, urea, α-D-mannose, cadaverine, glutamine, L-asparagine, D-gluconic acid, and indole could be regarded as specific potential metabolic markers for GI, as well as L-leucine for GT. In the GI subtype, D-gluconic acid and L-asparagine are positively correlated with activated partial thromboplastin time (APTT) and fibrinogen (FIB). In the GT subtype, L-leucine is positively correlated with the inflammatory marker C-reactive protein (CRP). Arginine and proline metabolism, glycine, serine and threonine metabolism, phenylalanine, tyrosine and tryptophan biosynthesis are the most important metabolic pathways associated with GI. The main metabolic pathways related to GT include pyrimidine metabolism, glutathione metabolism, biosynthesis of valine, leucine, and isoleucine, as well as valine, serine, and isoleucine with metabolites. The results of this study indicate that patients with different DFG subtypes have distinct metabolic profiles, which reflect the pathological characteristics of each subtype respectively. These findings will help us explore therapeutic targets for DFG and develop precise treatment strategies.

The therapeutic potential of Ziziphi Spinosae Semen and Polygalae Radix in insomnia management: Insights from gut microbiota and serum metabolomics techniques

Ethnopharmacological relevanceZiziphi Spinosae Semen and Polygalae Radix (ZSS-PR) constitute a traditional Chinese herbal combination with notable applications in clinical and experimental settings due to their evident sedative and calming effects. Aligned with traditional Chinese medicine principles, Ziziphi Spinosae Semen supports cardiovascular health, nourishes the liver, and induces mental tranquillity. Simultaneously, Polygalae Radix elicits calming effects, fosters clear thinking, and reinstates proper coordination between the heart and kidneys. ZSS-PR is commonly employed as a therapeutic intervention for various insomnia types, demonstrating distinct clinical efficacy. Our previous study findings provide evidence that ZSS-PR administration significantly reduces sleep onset latency, increases overall sleep duration, and improves abnormal neurotransmitter levels in a murine insomnia model. Aim of studyThis investigation aimed to scrutinize the intrinsic regulatory mechanism of ZSS-PR in managing insomnia using gut microbiota and serum metabolomics techniques. Materials and methodsMice were given DL-4-Chlorophenylalanine to induce insomnia and then treated with ZSS-PR. The open-field test assessed the animals' spontaneous activity. Concentrations of neurotransmitters, endocrine hormones, and cytokines in the duodenum were measured using enzyme linked immunosorbent assay, and brain histopathology was evaluated with H&E staining. The impact of ZSS-PR on the metabolic profile was examined by liquid chromatography couped to high resolution mass spectrometry, and 16S rDNA sequencing was used to study the influence of ZSS-PR on the gut microbiota. Additionally, the content of short-chain fatty acids (SCFAs) was analyzed by GC-MS. Finally, correlation analysis investigated relationships between biochemical markers, metabolites, SCFAs, and gut microbiota. ResultsZSS-PR treatment significantly increased movement time and distance in mice with insomnia and improved pathological impairments in the cerebral cortex and hippocampus. It also restored abnormal levels of biochemical markers in the gut of insomnia-afflicted mice, including 5-hydroxytryptamine, dopamine, gastrin, melatonin, tumour necrosis factor-α, and interleukin-1β. Metabolomics findings showed that ZSS-PR had a significant restorative effect on 15 endogenous metabolites in mice with insomnia. Furthermore, ZSS-PR primarily influenced five metabolic pathways, such as phenylalanine, tyrosine, and tryptophan biosynthesis, glutamine, and glutamate metabolism. Additionally, gut microbiota analysis revealed notable alterations in both diversity and microbial composition after ZSS-PR treatment. These changes were primarily attributed to the relative abundances of microbiota, including Firmicutes, Bacteroidota, Fusobacteriota, Muribaculaceae_unclassified, and Ligilactobacillus. The results of SCFAs analysis demonstrated that ZSS-PR effectively restored abnormal levels of acetic acid, propionic acid, isobutyric acid, butyric acid, isovaleric acid, and valeric acid in insomniac mice. Subsequent correlation analysis revealed that microbiota show obvious correlations with both biochemical markers and metabolites. ConclusionsThe results provide compelling evidence that ZSS-PR effectively mitigates abnormal activity, reduces cerebral pathological changes, and restores abnormal levels of neurotransmitters, endocrine hormones, and cytokines in mice with insomnia. The underlying mechanism is intricately linked to the modulation of gut microbiota and endogenous metabolic pathways.

Exploring the mechanism of Huanglian ointment in alleviating wound healing after anal fistula surgery through metabolomics and proteomics

Anal fistula is a common anal and intestinal disease. The wound of anal fistula surgery is open and polluting, which is the most difficult to heal among all surgical incisions. To investigate the mechanism of Huanglian ointment (HLO) on wound healing after anal fistula incision. The S. aureus infected wound in SD rats were used to imitate poor healing wound after anal fistula surgery. SD rats with wound sites (n = 24) were randomly divided into four groups (Control group, Model group, Potassium permanganate (PP) treatment group, and HLO treatment group). The wound healing rate was evaluated, HE staining was used to evaluate the pathological changes of each group, ELISA was used to detect the secretion of inflammatory factors in each group, and the mechanism was explored through metabolomics and proteomics in plasma rat. Compared to other groups, the rate of wound healing in the HLO group was higher on days 7 and 14. Histological analysis showed that collagen and fibroblast in HLO rats were significantly increased, inflammatory cells were reduced, and vascular endothelial permeability was increased. ELISA results showed that the secretion of inflammatory factors in HLO rats was significantly lower. Significant proteins and metabolites were identified in the wound tissues of the infected rats and HLO-treated rats, which were mainly attributed to Cdc42, Ctnnb1, Actr2, Actr3, Arpc1b, Itgam, Itgb2, Cttn, Linoleic acid metabolism, d-Glutamine and d-glutamate metabolism, Phenylalanine, tyrosine and tryptophan biosynthesis, Phenylalanine metabolism, alpha-Linolenic acid metabolism, and Ascorbate and aldarate metabolism. In conclusion, this study showed that HLO can promote S. aureus infected wound healing, and the data provide a theoretical basis for the treatment of wounds after anal fistula surgery with HLO.

Transcriptome analysis reveals the mechanism of NaHCO3 promoting tobacco leaf maturation.

NaHCO3 accelerates the aging of tobacco leaves; however, the underlying molecular mechanisms have not been elucidated. This study aimed to explore the mechanism of NaHCO3 in the promotion of tobacco leaf maturation using transcriptome analysis. Leaves on plants or detached leaves of the tobacco variety, Honghua Dajinyuan, were sprayed with or without 1% NaHCO3. The leaf yellowing was observed, the pigment content and enzyme activities were determined and RNA sequencing (RNA-seq) was performed. Spraying NaHCO3 onto detached leaves was found to promote leaf yellowing. Pigment content, catalase activity, and superoxide dismutase activity significantly decreased, whereas peroxidase activity and malondialdehyde content significantly increased. RNA-seq demonstrated that spraying with NaHCO3 upregulated genes associated with cysteine and methionine metabolism; alpha-linolenic acid metabolism; and phenylalanine, tyrosine, and tryptophan biosynthesis and downregulated genes related to photosynthesis and carotenoid biosynthesis. Genes correlated with autophagy-other, valine, leucine, and isoleucine degradation, and the MAPK signaling pathway were upregulated while those correlated with DNA replication, phenylalanine, and tyrosine and tryptophan biosynthesis were downregulated in detached leaves sprayed with NaHCO3 compared with the plant leaves sprayed with NaHCO3. Overall, this study is the first to elucidate the molecular and metabolic mechanisms of NaHCO3 in the promotion of tobacco leaf maturation.

Integrated metabolomics and network pharmacology study on the mechanism of herbal pair of danggui-kushen for treating ischemia heart disease

DangGui-KuShen (DK) is a well-known classic traditional Chinese medicine recipe that improves blood circulation, eliminates moisture, and detoxifies, and is frequently used in the treatment of cardiovascular problems. Some protective effects of DK on cardiovascular disease have previously been identified, but its precise mechanism remains unknown. The goal of this study is to combine metabolomics and network pharmacology to investigate DK's protective mechanism in Ischemic Heart Disease(IHD) rat models. A combination of metabolomics and network pharmacology based on UPLC-Q-TOF/MS technology was used in this study to verify the effect of DK on IHD through enzyme-linked immunosorbent assay, HE staining, and electrocardiogram, and it was determined that DK improves the synergistic mechanism of IHD. In total, 22 serum differential metabolites and 26 urine differential metabolites were discovered, with the majority of them involved in phenylalanine, tyrosine, and tryptophan biosynthesis, glycine, serine, and threonine metabolism, arginine and proline metabolism, aminoacyl-tRNA biosynthesis, purine metabolism, and other metabolic pathways. Furthermore, using network pharmacology, a composite target pathway network of DangGui and KuShen for treating IHD was created, which is primarily associated to the tumor necrosis factor (TNF) signaling pathway, P53 signaling, and HIF-1 signaling pathways. The combined research indicated that the NF-B signaling pathway and the HIF-1 signaling pathway are critical in DK treatment of IHD. This study clearly confirms and expands on current knowledge of the synergistic effects of DG and KS in IHD.

Exploration of the Amino Acid Metabolic Profiling and Pathway in Clonorchis sinensis-Infected Rats Revealed by the Targeted Metabolomic Analysis.

Background: Clonorchiasis remains a serious public health problem. However, the molecular mechanism underlying clonorchiasis remains largely unknown. Amino acid (AA) metabolism plays key roles in protein synthesis and energy sources, and improves immunity in pathological conditions. Therefore, this study aimed to explore the AA profiles of spleen in clonorchiasis and speculate the interaction between the host and parasite. Methods: Here targeted ultrahigh performance liquid chromatography multiple reaction monitoring mass spectrometry was applied to discover the AA profiles in spleen of rats infected with Clonorchis sinensis. Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis (KEGG) was performed to characterize the dysregulated metabolic pathways. Results: Pathway analysis revealed that phenylalanine, tyrosine, and tryptophan biosynthesis and β-alanine metabolism were significantly altered in clonorchiasis. There were no significant correlations between 14 significant differential AAs and interleukin (IL)-1β. Although arginine, asparagine, histidine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, and valine were positively correlated with IL-6, IL-10, tumor necrosis factor (TNF)-α as well as aspartate aminotransferase and alanine aminotransferase; β-alanine and 4-hydroxyproline were negatively correlated with IL-6, IL-10, and TNF-α. Conclusion: This study reveals the dysregulation of AA metabolism in clonorchiasis and provides a useful insight of metabolic mechanisms at the molecular level.

Transcriptional and functional predictors of potato virus Y-induced tuber necrosis in potato (Solanum tuberosum).

Potato (Solanum tuberosum L.), the fourth most important food crop in the world, is affected by several viral pathogens with potato virus Y (PVY) having the greatest economic impact. At least nine biologically distinct variants of PVY are known to infect potato. These include the relatively new recombinant types named PVY-NTN and PVYN-Wi, which induce tuber necrosis in susceptible cultivars. To date, the molecular plant-virus interactions underlying this pathogenicity have not been fully characterized. We hypothesized that this necrotic behavior is supported by transcriptional and functional signatures that are unique to PVY-NTN and PVYN-Wi. To test this hypothesis, transcriptional responses of cv. Russet Burbank, a PVY susceptible cultivar, to three PVY strains PVY-O, PVY-NTN, and PVYN-Wi were studied using mRNA-Seq. A haploid-resolved genome assembly for tetraploid potato was used for bioinformatics analysis. The study revealed 36 GO terms and nine KEGG 24 pathways that overlapped across the three PVY strains, making them generic features of PVY susceptibility in potato. Ten GO terms and three KEGG pathways enriched for PVY-NTN and PVYN-Wi only, which made them candidate functional signatures associated with PVY-induced tuber necrosis in potato. In addition, five other pathways were enriched for PVYNTN or PVYN-Wi. One carbon pool by folate was enriched exclusively in response to PVY-NTN infection; PVYN-Wi infection specifically impacted cutin, suberine and wax biosynthesis, phenylalanine metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, and monoterpenoid biosynthesis. Results suggest that PVYN-Wi-induced necrosis may be mechanistically distinguishable from that of PVY-NTN. Our study provides a basis for understanding the mechanism underlying the development of PVY-induced tuber necrosis in potato.

Metabolomic profiling of maternal plasma identifies inverse associations of acetate and urea with anti-SARS-CoV-2 antibody titers following COVID-19 vaccination during pregnancy.

We conducted a comprehensive metabolomic analysis of plasma samples obtained from pregnant women who displayed varying post-vaccination antibody titers after receiving mRNA-1273-SARS-CoV-2 vaccines. The study involved 62 pregnant women, all of whom had been vaccinated after reaching 24weeks of gestation. To quantify post-vaccination plasma antibody titers, we employed binding antibody units (BAU) in accordance with the World Health Organization International Standard. Subsequently, we classified the study participants into three distinct BAU/mL categories: those with high titers (above 2000), medium titers (ranging from 1000 to 2000), and low titers (below 1000). Plasma metabolomic profiling was conducted using 1H nuclear magnetic resonance spectroscopy, and the obtained data were correlated with the categorized antibody titers. Notably, in pregnant women exhibiting elevated anti-SARS-CoV-2 antibody titers, reduced plasma concentrations of acetate and urea were observed. A significant negative correlation between these compounds and antibody titers was also evident. An analysis of metabolomics pathways revealed significant inverse associations between antibody titers and four distinct amino acid metabolic pathways: (1) biosynthesis of phenylalanine, tyrosine, and tryptophan; (2) biosynthesis of valine, leucine, and isoleucine; (3) phenylalanine metabolism; and (4) degradation of valine, leucine, and isoleucine. Additionally, an association between the synthesis and degradation pathways of ketone bodies was evident. In conclusion, we identified different metabolic pathways that underlie the diverse humoral responses triggered by COVID-19 mRNA vaccines during pregnancy. Our data hold significant implications for refining COVID-19 vaccination approaches in expectant mothers. KEY MESSAGES : Anti-SARS-CoV-2 antibody titers decline as the number of days since COVID-19 vaccination increases. Anti-SARS-CoV-2 antibody titers are inversely associated with acetate, a microbial-derived metabolite, and urea. Amino acid metabolism is significantly associated with SARS-CoV-2 antibody titers.

Effects of dietary selenized glucose on intestinal microbiota and tryptophan metabolism in rats: Assessing skatole reduction potential

3-Methylindole (Skatole), a degradation product of tryptophan produced by intestinal microbial activity, significantly contributes to odor nuisance. Its adverse effects on animal welfare, human health, and environmental pollution have been noted. However, it is still unclear whether the intestinal microbiota mediates the impact of selenium (Se) on skatole production and what the underlying mechanisms remain elusive. A selenized glucose (SeGlu) derivative is a novel organic selenium compound. In this study, a diverse range of dietary SeGlu-treated levels, including SeGlu-deficient (CK), SeGlu-adequate (0.15 mg Se per L), and SeGlu-supranutritional (0.4 mg Se per L) conditions, were used to investigate the complex interaction of SeGlu on intestinal microbiome and serum metabolome changes in male Sprague-Dawley (SD) rats. The study showed that SeGlu supplementation enhanced the antioxidant ability in rats, significantly manifested in the increases of the activity of catalase (CAT) and glutathione peroxidase (GSH-Px), while no change in the level of malonaldehyde (MDA). Metagenomic sequencing analysis verified that the SeGlu treatment group significantly increased the abundance of beneficial microorganisms such as Clostridium, Ruminococcus, Faecalibacterium, Lactobacillus, and Alloprevotella while reducing the abundance of opportunistic pathogens such as Bacteroides and Alistipes significantly. Further metabolomic analysis revealed phenylalanine, tyrosine, and tryptophan biosynthesis changes in the SeGlu treatment group. Notably, the biosynthesis of indole, a critical pathway, was affected by SeGlu treatment, with several crucial enzymes implicated. Correlation analysis demonstrated strong associations between specific bacterial species - Treponema, Bacteroides, and Ruminococcus, and changes in indole and derivative concentrations. Moreover, the efficacy of SeGlu-treated fecal microbiota was confirmed through fecal microbiota transplantation, leading to a decrease in the concentration of skatole in rats. Collectively, the analysis of microbiota and metabolome response to diverse SeGlu levels suggests that SeGlu is a promising dietary additive in modulating intestinal microbiota and reducing odor nuisance in the livestock and poultry industry.

Therapeutic effect and mechanism of Jingfang Granules on acute lung injury based on intestinal flora and fecal metabolomics

This study aims to elucidate the therapeutic effect and mechanism of Jingfang Granules on acute lung injury, and to investigate the regulatory effect of Jingfang Granules on the metabolic disorders of endogenous metabolites in feces and the homeostasis of intestinal microbiota in acute lung injury, mice were randomly divided into a sham group, a model group, and a Jingfang Granules group. After modeling, the mice were continuously administered for 6 days. Using ultra-high performance liquid chromatography quadrupole/electrostatic field orbital trap high-resolution mass spectrometry(UHPLC-HESI-QE-Orbitrap-MS/MS) metabolomics technology and 16S rRNA high-throughput sequencing technology, changes in endogenous small molecule substances and gut microbiota in mouse intestines were determined, and potential biomarkers were identified. The results showed that Jingfang Granules can regulate 11 biomarkers, including L-glutamic acid, succinic acid, arachidonic acid, linoleic acid, linolenic acid, phenylalanine, sphingosine, 2-hydroxy-2-methyl butyric acid, pyruvate, tryptophan, and palmitic acid. Metabolic pathway analysis was conducted on these 11 biomarkers using the online software MetaboAnalyst, identifying potential major metabolic pathways. Among them, a total of 10 metabolic pathways are closely related to the treatment of acute lung injury with Jingfang Granules, including alanine, aspartate and glutamate metabolism, aminoacyl-tRNA biosynthesis, citrate cycle(TCA cycle), alyoxylate and dicarboxylate metabolism, arginine and proline metabolism, linoleic acid metabolism and linolenic acid metabolism, nitrogen metabolism, D-glutamine and D-gluta-matemetabolism, phenylalanine, tyrosine and tryptophan biosynthesis, phenylalanine metabolism. The results of gut microbiota showed significant differences in bacteria, mainly including Bacteroides, Akkermansia, Lachnospiraceae＿NK4A136＿group, Lachnochlostridium, and Klebsiella. Spearman analysis confirms that Akkermansia and Lachnospiraceae＿NK4A136＿group is a significant positive correlation between the abundance of succinic acid, arachidonic acid, linolenic acid, linoleic acid, butyric acid, and pyruvate in the group; Bacteroides, Klebsiella, Lachnochlostrium are significantly positively correlated with the abundance of L-glutamic acid, phenylalanine, and sphingosine. The above results indicate that the therapeutic effect of Jingfang Granules on acute lung injury is achieved by improving the imbalance of gut microbiota in mice with acute lung injury, balancing the metabolism of alanine, biosynthesis of aminoacyl tRNA, aspartic acid, glutamate, tricarboxylic acid cycle, biosynthesis of phenylalanine, tyrosine, tryptophan, and metabolism of linoleic acid.

Аминокислотный профиль при сниженном овариальном резерве

Diminished ovarian reserve (DOR) represents a relevant issue of reproductive medicine that is often associated with infertility and reduced efficacy of IVF programs. The changes in amino acid metabolism can play a role in the DOR pathogenesis as manifestations of the folliculogenesis and oogenesis epigenetic alterations. The study was aimed to assess alterations of amino acid metabolic pathways in blood plasma and follicular fluid and estimate their clinical significance in DOR. A total of 115 infertile women aged 25–42 years were included in the study. Groups were formed based on the ovarian reserve and age. Amino acid levels in blood plasma and follicular fluid were assessed by high performance liquid chromatography–mass spectrometry (HPLC-MS); bioinformatics analysis of amino acid metabolic pathways was performed. We revealed significant changes in the phenylalanine, tyrosine and tryptophan biosynthesis (effect = 0.5; p = 0.026), alanine, aspartate and glutamate metabolism (effect = 0.114; p = 0.013), and arginine biosynthesis (effect = 0.289; p < 0.001) pathways playing a role in folliculogenesis, oogenesis, and embryogenesis. The detected differences in the amino acid levels in various body fluids made it possible to construct the logistic regression models confirming DOR with the 88% probability based on the amino acid levels in follicular fluid (sensitivity 88%, specificity 84%) and 82% probability based on plasma levels (sensitivity 65%, specificity 91%). The findings can be used for further research focused on the pathogenesis of infertility associated with DOR and for selection of the most optimal diagnostic and treatment tactics.

Comprehensive pulmonary metabolic responses to silica nanoparticles exposure in Fisher 344 rats

Silica nanoparticles (SiNPs) could induce adverse pulmonary effects, but the mechanism was not clear enough. Metabolomics is a sensitive and high-throughput approach that could investigate the intrinsic causes of adverse health effects caused by SiNPs. The current investigation represented the first in vivo metabolomics study examining the chronic pulmonary toxicity of SiNPs at a low dosage, mimicking real human exposure situation. The recovery process after the cessation of exposure was also taken into consideration. Fisher 344 rats were treated with either saline or SiNPs for 6 months. Half of the animals in each group received an additional six-month period for recovery. The findings indicated that chronic low-level exposure to SiNPs resulted in notable alterations in pulmonary metabolism of amino acids, lipids, carbohydrates, and nucleotides. SiNPs exerted an impact on various metabolites and metabolic pathways which are linked to oxidative stress, inflammation and tumorigenesis. These included but were not limited to L-carnitine, spermidine, taurine, xanthine, and glutathione metabolism. The metabolic alterations caused by SiNPs exhibited a degree of reversibility. However, the interference of SiNPs on two metabolic pathways related to tumorigenesis was observed to persist after a recovery period. The two metabolic pathways are glycerophospholipid metabolism as well as phenylalanine, tyrosine and tryptophan biosynthesis. This study elucidated the metabolic alterations induced by chronic low-level exposure to SiNPs and presented novel evidence of the chronic pulmonary toxicity and carcinogenicity of SiNPs, from a metabolomic perspective.

Hydrolysis of Beef Sarcoplasmic Protein by Dry-Aged Beef-Isolated Penicillium oxalicum and Its Associated Metabolic Pathways.

Yanbian cattle have a unique meat flavor, and high-grade meat is in short supply. Therefore, in this study, we aimed to improve the added value of Yanbian cattle low-fat meat and provide a theoretical reference for the subsequent development of an excellent starter. Rump meat from Yanbian cattle was dry-aged and then screened for protease-producing fungi. Three protease-producing fungi (Yarrowia hollandica (D4 and D11), Penicillium oxalicum (D5), and Meesziomyces ophidis (D20)) were isolated from 40 d dry-aged beef samples, and their ability to hydrolyze proteins was determined using bovine sarcoplasmic protein extract. SDS-PAGE showed that the ability of Penicillium oxalicum (D5) to degrade proteins was stronger than the other two fungi. In addition, the volatile component content of sarcoplasmic proteins in the D5 group was the highest (45.47%) and comprised the most species (26 types). Metabolic pathway analysis of the fermentation broth showed that phenylalanine, tyrosine, and tryptophan biosynthesis was the most closely related metabolic pathway in sarcoplasmic protein fermentation by Penicillium oxalicum (D5). Dry-aged beef-isolated Penicillium oxalicum serves as a potential starter culture for the fermentation of meat products.

DIAMMONIUM GLYCYRRHIZINATE INHIBITED INFLAMMATORY RESPONSE AND MODULATED SERUM METABOLISM IN POLY(I:C)-INDUCED PNEUMONIA MODEL MICE.

Currently, the coronavirus disease 2019 (COVID-19) is becoming a serious threat to human health worldwide. Therefore, there is a great need to develop effective drugs against viral pneumonia. Diammonium glycyrrhizinate (DG), derived from Glycyrrhiza glabra L., has been demonstrated with significant anti-inflammatory properties. However, the therapeutic effects and mechanisms of DG on pneumonia require further clarification. In this study, mice received intratracheal injection of polyinosinic-polycytidylic acid (poly(I:C)) to induce pneumonia and were treated with DG. First, we evaluated the therapeutic potential of DG on poly(I:C)-induced pneumonia. Second, the anti-inflammatory and antioxidative activities and the impact of DG on the toll-like receptor 3 (TLR3) pathway were investigated. Third, the mechanism of DG was analyzed through untargeted metabolomics techniques. Our results revealed that DG intervention decreased permeability and reduced abnormal lung alterations in poly(I:C)-induced pneumonia model mice. DG intervention also downregulated cytokine levels in bronchoalveolar lavage fluid. Moreover, DG treatment inhibited the activation of TLR3 pathway. Furthermore, untargeted metabolomics analysis revealed that DG intervention could modulate serum metabolites involved in amino and nucleotide sugar metabolism, fructose and mannose metabolism, tyrosine metabolism, and phenylalanine, tyrosine, and tryptophan biosynthesis pathways. In conclusion, our study showed that DG could ameliorate poly(I:C)-induced pneumonia by inactivating the TLR3 pathway and affecting amino and nucleotide sugar, fructose and mannose metabolism, as well as tryptophan, phenylalanine, and tyrosine biosynthesis.

A metabolomics approach reveals metabolic disturbance of human cholangiocarcinoma cells after parthenolide treatment

Ethnopharmacological relevanceTanacetum parthenium (L.) Schultz-Bip, commonly known as feverfew, has been traditionally used to treat fever, migraines, rheumatoid arthritis, and cancer. Parthenolide (PTL), the main bioactive ingredient isolated from the shoots of feverfew, is a sesquiterpene lactone with anti-inflammatory and antitumor properties. Previous studies showed that PTL exerts anticancer activity in various cancers, including hepatoma, cholangiocarcinoma, acute myeloid leukemia, breast, prostate, and colorectal cancer. However, the metabolic mechanism underlying the anticancer effect of PTL remains poorly understood. Aim of the studyTo explore the anticancer activity and underlying mechanism of PTL in human cholangiocarcinoma cells. Material and methodsIn this investigation, the effects and mechanisms of PTL on human cholangiocarcinoma cells were investigated via a liquid chromatography/mass spectrometry (LC/MS)-based metabolomics approach. First, cell proliferation and apoptosis were evaluated using cell counting kit-8 (CCK-8), flow cytometry analysis, and western blotting. Then, LC/MS-based metabolic profiling along with orthogonal partial least-squares discriminant analysis (OPLS-DA) has been constructed to distinguish the metabolic changes between the negative control group and the PTL-treated group in TFK1 cells. Next, enzyme-linked immunosorbent assay (ELISA) was applied to investigate the changes of metabolic enzymes associated with significantly alerted metabolites. Finally, the metabolic network related to key metabolic enzymes, metabolites, and metabolic pathways was established using MetaboAnalyst 5.0 and Kyoto Encyclopedia of Genes and Genomes (KEGG) Pathway Database. ResultsPTL treatment could induce the proliferation inhibition and apoptosis of TFK1 in a concentration-dependent manner. Forty-three potential biomarkers associated with the antitumor effect of PTL were identified, which primarily related to glutamine and glutamate metabolism, alanine, aspartate and glutamate metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, phenylalanine metabolism, arginine biosynthesis, arginine and proline metabolism, glutathione metabolism, nicotinate and nicotinamide metabolism, pyrimidine metabolism, fatty acid metabolism, phospholipid catabolism, and sphingolipid metabolism. Pathway analysis of upstream and downstream metabolites, we found three key metabolic enzymes, including glutaminase (GLS), γ-glutamyl transpeptidase (GGT), and carnitine palmitoyltransferase 1 (CPT1), which mainly involved in glutamine and glutamate metabolism, glutathione metabolism, and fatty acid metabolism. The changes of metabolic enzymes associated with significantly alerted metabolites were consistent with the levels of metabolites, and the metabolic network related to key metabolic enzymes, metabolites, and metabolic pathways was established. PTL may exert its antitumor effect against cholangiocarcinoma by disturbing metabolic pathways. Furthermore, we selected two positive control agents that are considered as first-line chemotherapy standards in cholangiocarcinoma therapy to verify the reliability and accuracy of our metabolomic study on PTL. ConclusionThis research enhanced our comprehension of the metabolic profiling and mechanism of PTL treatment on cholangiocarcinoma cells, which provided some references for further research into the anti-cancer mechanisms of other drugs.

Alcohol extract of Rubia yunnanensis: Metabolic alterations and preventive effects against OGD/R‑induced oxidative damage in HT22 cells.

The present study investigated the inhibitory and neuroprotective effects of Rubia yunnanensis alcohol extract (RY-A) on oxidative stress induced by oxygen-glucose deprivation/reoxygenation (OGD/R) in HT22 cells. In vitro cultured HT22 cells were randomly divided into control, OGD/R, OGD/R + 100 µmol/l edaravone and OGD/R + 10, 20 and 40 µg/ml RY-A groups. Oxygen-sugar deprivation was performed with 10 mmol/l sodium dithionite combined with sugar-free DMEM medium for 2 h, followed by re-glycolization and reoxygenation for 2 h to establish an in vitro OGD/R model. Cell morphology was observed under a phase contrast microscope. Cell survival rate was detected by thiazolyl blue and lactate dehydrogenase and oxidative stress-related indexes were detected by commercial kits. The effects and metabolic alterations of RY-A treatment after OGD/R were evaluated using ultra-high performance liquid chromatography and mass spectrometry. Protein levels were further examined by western blotting. The results showed that cells in the OGD/R group were swollen and lacked protrusions, had significantly reduced viability and had significantly elevated oxidative stress-related indexes of reactive oxygen species, nitric oxide levels and malondialdehyde content and significantly reduced activities of the antioxidant enzymes superoxide dismutase and glutathione peroxidase, compared with controls. Compared with the OGD/R group, the RY-A group had significantly improved cell morphology and significantly increased cell viability and in terms of oxidative stress, exhibited significantly reduced reactive oxygen species, nitric oxide levels and malondialdehyde content, as well as significantly increased superoxide dismutase and glutathione peroxidase activities. Metabolomic analysis identified changes in 20 metabolites, including L-tryptophan, ornithine, eicosapentaenoic acid-d5, isosafrole and xanthine. Metabolomics analysis showed that the pathways affected included those related to phenylalanine, tyrosine and tryptophan biosynthesis, the prolactin signaling pathway and amphetamine addiction. These results suggested that RY-A had significant preventive effects on an in vitro model of cerebral ischemia-reperfusion injury simulated by OGD/R and the mechanism may be related to increased tryptophan content, activation of indoleamine 2,3-dioxygenase enzymes and inhibition of oxidative stress.

Effect of exogenous tannic acid on reduction of biogenic amines and citrinin in monascal soybean and metabolomics analysis

Biogenic amines (BAs) are often involved in human pathologies such as hypersensitivity symptoms. This research studied the effect of exogenous tannic acid (ETA) supplementation at various concentrations (0–20 mg/mL) on BA and mycotoxin citrinin levels in monascal soybean (MSB) and conducted a metabolomics analysis to estimate the metabolites in MSB. Addition of 20 mg/mL ETA decreased BA and citrinin levels in MSB after 25 days of fermentation by > 1.76 and >2.46 fold, respectively compared to the treatment without ETA addition. After 10 days of fermentation, the number of enterococci in MSB after treatment of >10 mg/mL ETA decreased by a minimum of 1.33 log CFU/g. ETA promoted large amounts of monacolin K, Monascus pigments, and free amino acids (FAAs) in MSB. A heatmap-HCA revealed that the 20 mg/mL ETA treatment was optimal, as confirmed by the VIP score and PCA. During MSB fermentation, seven notable metabolic pathways were identified as 1. phenylalanine metabolism, 2. arginine and proline metabolism, 3. phenylalanine, tyrosine, and tryptophan biosynthesis, 4. arginine biosynthesis, 5. histidine metabolism, 6. tryptophan metabolism, and 7. tyrosine metabolism. Supplementation of ETA in soybean substrate led to reduced BA and citrinin levels in MSB. The metabolomics analysis provide a better understanding of metabolite correlations, especially FAA formation and BA biosynthesis.

Alterations in serum metabolic profiles of early-stage hepatocellular carcinoma patients after radiofrequency ablation therapy

ObjectiveTo investigate the alterations in serum metabolic profiles and early-stage hepatocellular carcinoma (HCC) patient characteristics after radiofrequency ablation (RFA) therapy. This evaluation aimed to assess treatment effectiveness and identify potential novel approaches and targets for HCC treatment and prognosis monitoring. MethodsUntargeted metabolomics technology was employed to analyze serum metabolic profiles in healthy volunteer controls (NCs) and early stage HCC patients before and after RFA therapy. Additionally, Human Metabolome Database and Kyoto Encyclopedia of Genes and Genomes database were used to identify the differential metabolites (DMs) and metabolic pathways. Cystoscape was utilized to construct DM gene networks. Amino acid analyses were performed to validate our findings. ResultsWe identified 11, 14, and six DMs between the NC and HCC groups, HCC patients before and after RFA therapy, and post-RFA HCC and NC groups, respectively. The expression levels of these DMs, particularly those of amino acids and lipids, significantly changed. Compared with the NC group, higher levels of L-tyrosine, aspartate, and 18-oxo-oleate were observed in HCC patients, which were significantly reduced in patients after RFA therapy. Meanwhile, HCC patients after RFA therapy had increased levels of L-arginine, phosphatidic acid (20:3), and lysophosphatidyl choline (LPC) (20:4) compared to those before therapy, while their levels before therapy were lower than those of NC. Moreover, most metabolites in the post-RFA and NC groups showed no significant changes in expression, except for L-tyrosine and LPC (16:0). These metabolites could potentially serve as characteristic factors of early-stage HCC patients after RFA therapy. Joint pathway analysis revealed striking changes, mainly in phenylalanine, tyrosine, and tryptophan biosynthesis; alanine, aspartate, and glutamate metabolism; and arginine and aminoacyl-tRNA biosynthesis. Bioinformatics analysis of publicly available data preliminarily identified 187 DM-related metabolic enzymes. ConclusionOur study proposed novel targets for early-stage HCC treatment, laying the groundwork for improving treatment efficacy and prognosis of early-stage HCC patients.

Analyses of plasma metabolites using a high performance four-channel CIL LC-MS method and identification of metabolites associated with enteric methane emissions in beef cattle.

Reducing enteric methane (one greenhouse gas) emissions from beef cattle not only can be beneficial in reducing global warming, but also improve efficiency of nutrient utilization in the production system. However, direct measurement of enteric methane emissions on individual cattle is difficult and expensive. The objective of this study was to detect plasma metabolites that are associated with enteric methane emissions in beef cattle. Average enteric methane emissions (CH4) per day (AVG_DAILYCH4) for each individual cattle were measured using the GreenFeed emission monitoring (GEM) unit system, and beef cattle with divergent AVG_DAILYCH4 from Angus (n = 10 for the low CH4 group and 9 for the high CH4 group), Charolais (n = 10 for low and 10 for = high), and Kinsella Composite (n = 10 for low and 10 for high) populations were used for plasma metabolite quantification and metabolite-CH4 association analyses. Blood samples of these cattle were collected near the end of the GEM system tests and a high performance four-channel chemical isotope labeling (CIL) liquid chromatography (LC) mass spectrometer (MS) method was applied to identify and quantify concentrations of metabolites. The four-channel CIL LC-MS method detected 4235 metabolites, of which 1105 were found to be significantly associated with AVG_DAILYCH4 by a t-test, while 1305 were significantly associated with AVG_DAILYCH4 by a regression analysis at p<0.05. Both the results of the t-test and regression analysis revealed that metabolites that were associated with enteric methane emissions in beef cattle were largely breed-specific whereas 4.29% to 6.39% CH4 associated metabolites were common across the three breed populations and 11.07% to 19.08% were common between two breed populations. Pathway analyses of the CH4 associated metabolites identified top enriched molecular processes for each breed population, including arginine and proline metabolism, arginine biosynthesis, butanoate metabolism, and glutathione metabolism for Angus; beta-alanine metabolism, pyruvate metabolism, glycolysis / gluconeogenesis, and citrate cycle (TCA cycle) for Charolais; phenylalanine, tyrosine and tryptophan biosynthesis, phenylalanine metabolism, arginine biosynthesis, and arginine and proline metabolism for Kinsella Composite. The detected CH4 associated metabolites and enriched molecular processes will help understand biological mechanisms of enteric methane emissions in beef cattle. The detected CH4 associated plasma metabolites will also provide valuable resources to further characterize the metabolites and verify their utility as biomarkers for selection of cattle with reduced methane emissions.