Cysteine Metabolism Research Articles

Physiological and Transcriptome Analysis on Diploid and Polyploid Populus ussuriensis Kom. under Salt Stress.

Populus ussuriensis Kom. is a valuable forest regeneration tree species in the eastern mountainous region of Northeast China. It is known that diploid P. ussuriensis (CK) performed barely satisfactorily under salt stress, but the salt stress tolerance of polyploid (i.e., triploid (T12) and tetraploid (F20)) P. ussuriensis is still unknown. In order to compare the salt stress tolerance and salt stress response mechanism between diploid and polyploid P. ussuriensis, phenotypic observation, biological and biochemistry index detections, and transcriptome sequencing (RNA-seq) were performed on CK, T12, and F20. Phenotypic observation and leaf salt injury index analysis indicated CK suffered more severe salt injury than T12 and F20. SOD and POD activity detections indicated the salt stress response capacity of T12 was stronger than that of CK and F20. MDA content, proline content and relative electric conductivity detections indicated CK suffered the most severe cell-membrane damage, and T12 exhibited the strongest osmoprotective capacity under salt stress. Transcriptome analysis indicated the DEGs of CK, T12, and F20 under salt stress were different in category and change trend, and there were abundant WRKY, NAM, MYB and AP2/ERF genes among the DEGs in CK, T12, and F20 under salt stress. GO term enrichment indicated the basic growth progresses of CK, and F20 was obviously influenced, while T12 immediately launched more salt stress response processes in 36 h after salt stress. KEGG enrichment indicated the DEGs of CK mainly involved in plant–pathogen interaction, ribosome biogenesis in eukaryotes, protein processing in endoplasmic reticulum, degradation of aromatic compounds, plant hormone signal transduction, photosynthesis, and carbon metabolism pathways. The DEGs of T12 were mainly involved in plant–pathogen interaction, cysteine and methionine metabolism, phagosomes, biosynthesis of amino acids, phenylalanine, tyrosine and tryptophan biosynthesis, plant hormone signal transduction, and starch and sucrose metabolism pathways. The DEGs of F20 were mainly involved in plant hormone signal transduction, plant–pathogen interaction, zeatin biosynthesis, and glutathione metabolism pathways. In conclusion, triploid exhibited stronger salt stress tolerance than tetraploid and diploid P. ussuriensis (i.e., T12 > F20 > CK). The differences between the DEGs of CK, T12, and F20 probably are the key clues for discovering the salt stress response signal transduction network in P. Ussuriensis.

Integrated strategy for mechanism of Baitouweng Decoction in treating dampness-heat diarrhea based on urine metabolomics coupled with network pharmacology

Baitouweng Decoction is a famous Chinese medicinal decoction that has been used to treat diarrhea over thousands of years. In this study, we investigated the effect and mechanism of Baitouweng Decoction in the treatment of diarrhea. Wistar rats were randomly assigned into 4 groups: control group, dampness-heat diarrhea model group(modeling by complex factors including high-sugar and high-fat diet, improper diet, hot and humid environment, drinking and intraperitoneal injection of Escherichia coli), Baitouweng Decoction(3.6 g·kg~(-1)) group, and self-healing group. A urine metabolomics approach was developed with ultra liquid chromatography-quadrupole-time-of-flight-mass spectrometry(UPLC-Q-TOF-MS) for metabolic profiling. The differential metabolites were screened out by the multivariate comparison between groups. Diarrhea-related protein targets and the active compounds of Baitouweng Decoction were used to predict the protein targets of Baitouweng Decoction. Cytoscape 3.2.1 was employed to establish a active component-target protein interaction network. Three protein-protein interaction(PPI) networks of component target proteins, diarrhea-related proteins, and differential metabolite-related proteins were established and then merged by BisoGenet. ClueGO was used to perform the gene enrichment based on the genetic similarity. The results showed that Baitouweng Decoction effectively treated dampness-heat diarrhea in vivo. N-acetylserotonin, L-gamma-glutamylcysteine, glutathione, retinoate, melatonin, indole-3-acetaldehyde, L-cystine, biotin, and L-tryptophan were screened as differential metabolites in dampness-heat diarrhea model group. Tryptophan metabolism, glutathione metabolism, biotin metabolism, retinol metabolism, and cysteine and methionine metabolism were involved in the therapeutic effect of Baitouweng Decoction in vivo. A total of 167 targets were identified as major candidates for diarrhea progression. The gene-set enrichment revealed that the targets were involved in reactive oxygen species production, inflammation, and apoptosis. Baitouweng Decoction can restrain inflammation, production of reactive oxygen, and block apoptosis, thereby contributing to the treatment of dampness-heat diarrhea.

High Expression of Heat Shock Protein Family D Member 1 Predicts Poor Prognosis of Esophageal Cancer.

BackgroundHeat shock protein family D (Hsp60) member 1 (HSPD1) has been reported as a potential survival-related biomarker in some cancers. However, the correlation between HSPD1 expression with prognosis and clinical features of esophageal cancer (EC) is poorly understood. Our research aimed to explore the clinical and prognostic significance of HSPD1 expression in EC patients.MethodsIn our study, HSPD1 expression was detected by immunochemistry in 87 EC tissue specimens and 20 normal cancerous peripheral tissue specimens. Meanwhile, we also analyzed the expression of HSPD1 in EC by The Cancer Genome Atlas (TCGA) database. Then Chi-squared and Fisher’s exact tests and Wilcoxon signed-rank test and logistic regression models were separately used to test the correlation between clinical characteristics and HSPD1 expression in our and TCGA cohort. Moreover, we evaluated the value of HSPD1 in prognosis by Kaplan-Meier curves and Cox analysis. Finally, gene set enrichment analysis (GSEA) was performed using the data accessed from TCGA.ResultsThe results showed that HSPD1 was overexpressed in EC, and the expression was related to histological type, histological grade, N classification, and clinical stage. Moreover, Kaplan-Meier curves and Cox analysis indicated that high expression of HSPD1 correlated with poor prognosis, and HSPD1 was an independent risk factor for EC. GSEA identified pathways involved in cysteine and methionine metabolism, spliceosome, selenoamino acid metabolism, mismatch repair, RNA degration, DNA replication, and cell cycle as differentially enriched in ECs with high HSPD1 expression.ConclusionsOur results suggest that HSPD1 is expressed at high levels in EC, and has potential to be used as a novel biomarker for the prognosis of patients with EC.

Insights from a Multi-Omics Integration (MOI) Study in Oil Palm (Elaeis guineensis Jacq.) Response to Abiotic Stresses: Part One-Salinity.

Oil palm (Elaeis guineensis Jacq.) is the number one source of consumed vegetable oil nowadays. It is cultivated in areas of tropical rainforest, where it meets its natural condition of high rainfall throughout the year. The palm oil industry faces criticism due to a series of practices that was considered not environmentally sustainable, and it finds itself under pressure to adopt new and innovative procedures to reverse this negative public perception. Cultivating this oilseed crop outside the rainforest zone is only possible using artificial irrigation. Close to 30% of the world’s irrigated agricultural lands also face problems due to salinity stress. Consequently, the research community must consider drought and salinity together when studying to empower breeding programs in order to develop superior genotypes adapted to those potential new areas for oil palm cultivation. Multi-Omics Integration (MOI) offers a new window of opportunity for the non-trivial challenge of unraveling the mechanisms behind multigenic traits, such as drought and salinity tolerance. The current study carried out a comprehensive, large-scale, single-omics analysis (SOA), and MOI study on the leaves of young oil palm plants submitted to very high salinity stress. Taken together, a total of 1239 proteins were positively regulated, and 1660 were negatively regulated in transcriptomics and proteomics analyses. Meanwhile, the metabolomics analysis revealed 37 metabolites that were upregulated and 92 that were downregulated. After performing SOA, 436 differentially expressed (DE) full-length transcripts, 74 DE proteins, and 19 DE metabolites underwent MOI analysis, revealing several pathways affected by this stress, with at least one DE molecule in all three omics platforms used. The Cysteine and methionine metabolism (map00270) and Glycolysis/Gluconeogenesis (map00010) pathways were the most affected ones, each one with 20 DE molecules.

Combined Analysis of BSA-Seq Based Mapping, RNA-Seq, and Metabolomic Unraveled Candidate Genes Associated with Panicle Grain Number in Rice (Oryza sativa L.).

Rice grain yield is a complex and highly variable quantitative trait consisting of several key components, including the grain weight, the effective panicles per unit area, and the grain number per panicle (GNPP). The GNPP is a significant contributor to grain yield controlled by multiple genes (QTL) and is crucial for improvement. Attempts have been made to find genes for this trait, which has always been a challenging and arduous task through conventional methods. We combined a BSA analysis, RNA profiling, and a metabolome analysis in the present study to identify new candidate genes involved in the GNPP. The F2 population from crossing R4233 (high GNPP) and Ce679 (low GNPP) revealed a frequency distribution fitting two segregated genes. Three pools, including low, middle, and high GNPP, were constructed and a BSA analysis revealed six candidate regions spanning 5.38 Mb, containing 739 annotated genes. Further, a conjunctive analysis of BSA-Seq and RNA-Seq showed 31 differentially expressed genes (DEGs) in the candidate intervals. Subsequently, a metabolome analysis showed 1024 metabolites, with 71 significantly enriched, including 44 up and 27 downregulated in Ce679 vs. R4233. A KEGG enrichment analysis of these 31 DEGs and 71 differentially enriched metabolites (DEMs) showed two genes, Os12g0102100 and Os01g0580500, significantly enriched in the metabolic pathways’ biosynthesis of secondary metabolites, cysteine and methionine metabolism, and fatty acid biosynthesis. Os12g0102100, which encodes for the alcohol dehydrogenase superfamily and a zinc-containing protein, is a novel gene whose contribution to the GNPP is not yet elucidated. This gene coding for mitochondrial trans-2-enoyl-CoA reductase is involved in the biosynthesis of myristic acid, also known as tetradecanoic acid. The Os01g0580500 coding for the enzyme 1-aminoclopropane-1-carboxylate oxidase (OsACO7) is responsible for the final step of the ethylene biosynthesis pathway through the conversion of 1-aminocyclopropane-1-carboxylic acid (ACC) into ethylene. Unlike Os12g0102100, this gene was significantly upregulated in R4233, downregulated in Ce679, and significantly enriched in two of the three metabolite pathways. This result pointed out that these two genes are responsible for the difference in the GNPP in the two cultivars, which has never been identified. Further validation studies may disclose the physiological mechanisms through which they regulate the GNPP in rice.

Integrated 16S rDNA, metabolomics, and TNF-α/NF-κB signaling pathway analyses to explain the modulatory effect of Poria cocos aqueous extract on anxiety-like behavior

BackgroundPoria cocos is an ancient medicine and modern functional food, which exerts excellent effects on anxiety, although its mechanism is unknown. PurposeTo explore the mechanisms of the aqueous extract of P. cocos (PCD) in ameliorating anxiety-like behavior caused by chronic sleep deprivation (CSD). MethodsPCD chemical composition was analyzed by UPLC-QTOF-MS/MS. A CSD rat model was established over 21 days. We examined the effects and mechanisms after 10 days of CSD using open-field tests (OFTs), enzyme-linked immunosorbent assays, 16S rDNA, non-targeted metabolomics, and Western blot analyses. ResultsSixty-two triterpenoids were identified in PCD. CSD-induced anxiety-like behavior was significantly attenuated by PCD treatment. PCD improved hypothalamic neurotransmitters, decreased proinflammatory cytokines, and depressed the proteins expression of tumor necrosis factor (TNF)-α/nuclear factor (NF)-κB signaling pathway. The full-length 16S rDNA sequence of bacterial cells was also sequenced by high-throughput analysis. CSD caused significant changes in the intestinal flora. PCD improved the species diversity and bacterial abundance in the intestines of rats with anxiety. Metabolomics analysis indicated that 12 PCD-related metabolites in serum and 32 PCD-related metabolites in feces were identified, respectively. Metabolite analysis in serum, PCD treatment affected taurine, hypotaurine, cysteine, methionine, glycine, serine, and threonine metabolism, among others. Metabolite analysis in feces showed significant effects of PCD treatment on the metabolism of vitamin B6, tyrosine, drugs, and glycerophospholipid. Additionally, the correlation analysis of heatmaps showed a tight relationship between inflammatory factors, metabolic parameters, and gut microbial phylotypes. ConclusionsPCD relieved anxiety by regulating intestinal flora, regulating metabolic disorders, and inhibiting inflammatory pathways in chronic sleep-deprived rats.

Antimicrobial activity of green synthesized Se nanoparticles using ginger and onion extract: a laboratory and in silico analysis

We present the green synthesis of selenium nanoparticles using onion and ginger extracts and their characterization. Subsequently, the antimicrobial effect of the nanoparticles against Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, and Salmonella paratyphi was tested. Furthermore, this study implemented an in silico analysis using the STITCH database to generate protein-selenium interaction networks and predict altered KEGG pathways in the studied bacteria. The results showed the maximum UV-visible absorbance at approximately 550 nm confirming the synthesis of nanoparticles. Furthermore, the phenolic compounds identified to enhance the synthesis and stabilize selenium nanoparticles. The synthesized nanoparticles are spherical at about 100 nm. Selenium nanoparticles showed only an inhibitory effect on the growth of Staphylococcus aureus. According to in silico analysis, nanoparticles cause an inhibition of the growth of Staphylococcus aureus by an alteration in the metabolism of cysteine, methionine and arachidonic acid.

S-Adenosylmethionine-responsive cystathionine β-synthase modulates sulfur metabolism and redox balance in Mycobacterium tuberculosis.

Methionine and cysteine metabolisms are important for the survival and pathogenesis of Mycobacterium tuberculosis (Mtb). The transsulfuration pathway converts methionine to cysteine and represents an important link between antioxidant and methylation metabolism in diverse organisms. Using a combination of biochemistry and cryo–electron microscopy, we characterized the first enzyme of the transsulfuration pathway, cystathionine β-synthase (MtbCbs) in Mtb. We demonstrated that MtbCbs is a heme-less, pyridoxal-5′-phosphate–containing enzyme, allosterically activated by S-adenosylmethionine (SAM). The atomic model of MtbCbs in its native and SAM-bound conformations revealed a unique mode of SAM-dependent allosteric activation. Further, SAM stabilized MtbCbs by sterically occluding proteasomal degradation, which was crucial for supporting methionine and redox metabolism in Mtb. Genetic deficiency of MtbCbs reduced Mtb survival upon homocysteine overload in vitro, inside macrophages, and in mice coinfected with HIV. Thus, the MtbCbs-SAM axis constitutes an important mechanism of coordinating sulfur metabolism in Mtb.

Integrated multi-omics analyses reveals molecules governing sperm metabolism potentially influence bull fertility

Bull fertility is of paramount importance in bovine industry because semen from a single bull is used to breed several thousands of cows; however, so far, no reliable test is available for bull fertility prediction. In the present study, spermatozoa from high- and low-fertility bulls were subjected to high-throughput transcriptomic, proteomic and metabolomic analysis. Using an integrated multi-omics approach the molecular differences between high- and low-fertility bulls were identified. We identified a total of 18,068 transcripts, 5041 proteins and 3704 metabolites in bull spermatozoa, of which the expression of 4766 transcripts, 785 proteins and 33 metabolites were dysregulated between high- and low-fertility bulls. At transcript level, several genes involved in oxidative phosphorylation pathway were found to be downregulated, while at protein level genes involved in metabolic pathways were significantly downregulated in low-fertility bulls. We found that metabolites involved in Taurine and hypotaurine metabolism were significantly downregulated in low-fertility bulls. Integrated multi-omics analysis revealed the interaction of dysregulated transcripts, proteins and metabolites in major metabolic pathways, including Butanoate metabolism, Glycolysis and gluconeogenesis, Methionine and cysteine metabolism, Phosphatidyl inositol phosphate, pyrimidine metabolism and saturated fatty acid beta oxidation. These findings collectively indicate that molecules governing sperm metabolism potentially influence bull fertility.

Impact of intracellular response regulator QseB in quorum sensing regulatory network in a clinical isolate SC1401 of Glaesserella parasuis

Two component systems (TCS) mediate specific responses to different conditions and/or pressures. In the quorum sensing Glaesserella parasuis (QSE) BC TCS, qseB, as a response regulator, is closely related to the transcriptional regulation of multiple downstream genes. In this study, the effects of qseB gene deletion, which encodes the response regulator of population density sensing in G. parasuis, were studied through biological characteristics and metabolomic analysis. Based on previous research, we further explored the virulence of ΔqseB mutant strains through cell morphology, adhesion and invasion. The ΔqseB mutant and parent strains were sequenced by metabolome and combined with the previous transcriptome sequencing results for joint analysis. This study aims to clarify the regulatory effect of QseB on the virulence of G. parasuis and lay the foundation for revealing the pathogenic mechanism of G. parasuis. We detected 476 different metabolites, of which 30 metabolites (6.3%) had a significant difference in abundance between SC1401 and ΔqseB (p < 0.05). We conducted a comparative analysis of pathway enrichment on the transcriptome and metabolome, and found that the two omics participate in seven metabolic pathways together. The top 10 KEGG pathways with the largest number of genes and metabolites identified in this experiment are ABC transporters, Biosynthesis of secondary metabolites, Cysteine and methionine metabolism, Purine metabolism, Pyrimidine metabolism, Metabolic pathways, and Nicotinate and nicotinamide metabolism. Analysis of metabolome sequencing results showed that differential metabolites were also enriched in metabolic pathways, such as Purine metabolism, cGMP-PKG signaling pathway and cAMP signaling pathway, which were not found in transcriptome sequencing data. The internal coloration of the mutant strain ΔqseB was uneven, and the adhesion and invasion ability of PAM cell lines were significantly reduced. We speculate that QseB may affect the adhesion and invasion ability of Glaesserella parasuis by influencing substance transport and signal transduction.

Shotgun proteomic investigation of methyltransferase and methylation profiles in lipopolysaccharide stimulated RAW264.7 murine macrophages.

Arginine methylation is a common post-translational modification which functions as an epigenetic regulator of transcription and plays a key role in various cell signaling pathways. The methylation of arginine residues is catalyzed by protein arginine methyltransferase (PRMT). However, the expression pattern and underlying mechanism of PRMTs and protein methylation profile in lipopolysaccharide (LPS)-induced innate immune responses are poorly understood. Using a shotgun proteomic approach, we found that LPS stimulation increased arginine and proline metabolism and responses to inflammation and bacterial infections. In comparison, cysteine and methionine metabolism, the pentose phosphate pathway, purine metabolism, and protein methylation factors were also decreased in LPS stimulated murine macrophage cell lines. We revealed that LPS stimulation downregulated PRMT1, PRMT5, and protein arginine methylation profiles in RAW264.7 cells using western blot analysis. Additionally, this phenomenon occurred in parallel with nitric oxide accumulation in LPS-induced macrophages. Using inflammation models, we demonstrate for the first time that LPS stimulation decreases PRMTs, leading to the decreasing of arginine methylation in macrophages.

Abstract 3031: Impact of pyruvate kinase isoforms on cysteine metabolism in pancreatic cancer

Abstract Pancreatic cancer cells undergo metabolic alterations to survive within a nutrient-depleted tumor microenvironment. Cysteine metabolism in particular is critical for supporting pancreatic cancer cell survival through its role in redox homeostasis. Targeting cysteine metabolism presents an underexplored opportunity for therapeutic exploitation, but much remains unknown about how cysteine metabolism is influenced by microenvironmental conditions and the overall metabolic state of the cell. One critical metabolic shift in pancreatic cancer cells occurs through altered isoform expression of the glycolytic enzyme, pyruvate kinase (PKM). Pancreatic cancer cells preferentially switch from the constitutively active M1 isoform to the allosterically regulated M2 isoform of PKM. Overexpression of PKM2 in pancreatic cancer cells produces a profound reprogramming of many metabolic pathways; however, the precise relationship between PKM isoform expression and cysteine metabolism is not well understood. We hypothesize that PKM isoform selection enables pancreatic cancer cell survival within a low cystine tumor microenvironment by reprogramming metabolic activity to increase cystine import and glutathione production and modulate glucose and glutamine metabolism to resist oxidative stress. We used lentiviral CRISPR-Cas9 vectors to genetically modify two human pancreatic ductal adenocarcinoma cell lines, AsPC-1 and Panc-1, to exclusively express either PKM1 or PKM2. We evaluated the effects of PKM isoform selection on tolerance of low cystine environments by assessing viability under a range of cystine concentrations (0 – 50 μM) reflective of physiologic and cystine starvation conditions. We observe altered viability and proliferation in PKM1 vs. PKM2 expressing cells under normoxic (21%) and hypoxic (1% O2) conditions. Targeted metabolomics using stable isotope labeling tracers further reveal impacts of PKM isoform expression in central carbon metabolism when cystine is limited. Additional experiments to elucidate the precise mechanism by which PKM isoform expression impacts pancreatic cancer cells are currently under investigation. This study provides valuable insight into the complexities of metabolic reprogramming within the tumor microenvironment and enhances our understanding of how cysteine metabolism could be targeted for the treatment of pancreatic cancer. Citation Format: Elliot Ensink, Sophia Y. Lunt. Impact of pyruvate kinase isoforms on cysteine metabolism in pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3031.

Metabolomic changes of neonatal sepsis: an exploratory clinical study

To study the metabolic mechanism of neonatal sepsis at different stages by analyzing the metabolic pathways involving the serum metabolites with significant differences in neonates with sepsis at different time points after admission. A total of 20 neonates with sepsis who were hospitalized in the Department of Neonatology, Hunan Provincial People's Hospital, from January 1, 2019 to January 1, 2020 were enrolled as the sepsis group. Venous blood samples were collected on days 1, 4, and 7 after admission. Ten healthy neonates who underwent physical examination during the same period were enrolled as the control group. Ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry was used for the metabonomic analysis of serum samples to investigate the change in metabolomics in neonates with sepsis at different time points. On day 1 after admission, the differentially expressed serum metabolites between the sepsis and control groups were mainly involved in the biosynthesis of terpenoid skeleton. For the sepsis group, the differentially expressed serum metabolites between days 1 and 4 after admission were mainly involved in pyruvate metabolism, and those between days 4 and 7 after admission were mainly involved in the metabolism of cysteine and methionine. The differentially expressed serum metabolites between days 1 and 7 after admission were mainly involved in ascorbic acid metabolism. The metabolic mechanism of serum metabolites varies at different stages in neonates with sepsis and is mainly associated with terpenoid skeleton biosynthesis, pyruvate metabolism, cysteine/methionine metabolism, and ascorbic acid metabolism.

Abstract 3032: Selenoprotein Sepp1 determines cysteine dependence in pancreatic cancer

Abstract Pancreatic cancer (PaCa) represents the fourth leading cause of overall cancer death, despite its relatively low incidence compared to other malignancies (Lung, prostate, breast, etc.). Approximately 57,600 people were estimated to be diagnosed with pancreatic cancer in the USA, and 47,050 were estimated to die of the disease in 2020 reported by The American Cancer Society. Novel effective therapeutic strategies are urgently needed. Metabolic changes are typically associated with tumor development to support fast cell proliferation and malignant transition. Such metabolic deregulations differentiate tumor cells from normal cells and act as potential targets of anticancer therapies. Previous studies have shown cysteine dependence often presents in various cancers, since cysteine metabolism supplies glutathione - an important substrate for the cellular reactive oxygen species (ROS) cleanup cycle. Studies in breast and kidney cancers have shown that such cysteine-dependence is a prominent feature in the cancer subtypes with a mesenchymal cell phenotype, instead of in the epithelial subtype. We found that cysteine dependence exists in pancreatic cancer as well. Mesenchymal PaCa cells, in contrast to the epithelial tumor cells, appear to be more sensitive to cysteine depletion with extensive induction of ferroptosis, a programmed cell death pathway involving iron and lipid peroxidation. Gene expression analysis revealed the selenium transporter protein Sepp1 to be absent in the mesenchymal PaCa cells. Knockdown of Sepp1 expression in cysteine-independent cells renders cells dependent on cysteine. Selenium is a micronutrient required for the synthesis of selenoproteins including GPX4 and Sepp1. The addition of selenium alleviated cell reliance on cysteine and caused resistance to GPX4 inhibitor-induced ferroptosis. We observed that Sepp1 regulates the thioredoxin pathway to rescue the cells under the glutathione deficiency. Interestingly, the conditioned media assay also revealed that Sepp1 protects cells from ROS stress by a symbiotic mechanism. Our findings suggest that Sepp1 could serve as a biomarker of tumor cysteine-dependency and a potential molecular target for therapeutic strategies to overcome drug resistance in pancreatic cancer. Citation Format: Arslan Amer, Tahiyat Alothaim, Xiaohu Tang. Selenoprotein Sepp1 determines cysteine dependence in pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3032.

Reversely immortalized mouse salivary gland cells presented a promising metabolic and fibrotic response upon BMP9/Gdf2 stimulation

The submandibular gland (SMG) and the sublingual gland (SLG) are two of the three major salivary glands in mammals. In mice, they are adjacent to each other and open into the oral cavity, producing saliva to lubricate the mouth and aid in food digestion. Though salivary gland dysfunction accompanied with fibrosis and metabolic disturbance is common in clinic, in-depth mechanistic research is lacking. Currently, research on how to rescue salivary function is challenging, as it must resort to using terminally differentiated acinar cells or precursor acinar cells with unknown differentiation. In this study, we established reversely immortalized mouse primary SMG cells (iSMGCs) and SLG cells (iSLGCs) on the first postnatal day (P0). The iSMGCs and iSLGCs grew well, exhibited many salivary gland characteristics, and retained the metabolism-related genes derived from the original tissue as demonstrated using transcriptome sequencing (RNA-seq) analysis. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways of these two cell lines, which overlapped with those of the SMG and SLG, were enriched in cysteine and methionine metabolism. Furthermore, we investigated the role of bone morphogenetic protein 9 (BMP9), also known as growth differentiation factor 2(Gdf2), on metabolic and fibrotic functions in the SMG and SLG. We demonstrated that iSMGCs and iSLGCs presented promising adipogenic and fibrotic responses upon BMP9/Gdf2 stimulation. Thus, our findings indicate that iSMGCs and iSLGCs faithfully reproduce characteristics of SMG and SLG cells and present a promising prospect for use in future study of salivary gland metabolism and fibrosis upon BMP9/Gdf2 stimulation.

Investigation of the apoptosis-inducing effect of docetaxel by comprehensive LC-MS-based metabolomics and network pharmacology approaches.

Docetaxel is one of the clinical first-line drugs and its combination with other chemotherapy agents for advanced or metastatic cancers has attracted widespread attention. Therefore, to promote the clinical application of docetaxel alone or in combination, a comprehensive investigation of the metabolic mechanism of docetaxel is of great importance. Here, we apply an integrative analysis of metabolomics and network pharmacology to elucidate the underlying mechanisms of docetaxel. After taking the intersection of the aforesaid two methods, five pathways including ABC (ATP-binding cassette) transporters, central carbon metabolism in cancer, glycolysis and gluconeogenesis, cysteine and methionine metabolism, and arginine biosynthesis have been screened. Concerning the interaction network of these pathways and the anti-apoptosis effect of docetaxel itself, the central carbon metabolism in cancer pathway was mainly focused on. This study may help delineate global landscapes of cellular protein-metabolite interactions, to provide molecular insights about their mechanisms of action as well as to promote their clinical applications.

Asymmetry Evaluation of Sea Cucumber (Apostichopus japonicus) Gut and Its Surrounding Environment in the Bacterial Community

Animals are not only regulated by their own genes but also influenced by symbiotic bacteria, most of which are colonized in the gut. The gut bacterial community is involved in plenty of physiological processes; therefore, intestinal colonization by commensal microbiota is essential to the health of the host animal. Here, metagenome sequencing of the A. japonicus gut, surrounding water, and feed was performed to explore the structural and functional characteristics of the colonized bacteria in the gut of A. japonicus. Results showed that Bacteroidetes and Proteobacteria were the main dominant phyla of the A. japonicus gut, and Formosa, Vibrio, and Lactobacillus were the dominant genera. There was asymmetry between the A. japonicus gut and its surrounding environment in the bacterial community. In terms of the top 50 abundant genera, those colonized in the gut shared a similarity of 26% with those colonized in the surrounding water and a similarity of 30% with those colonized in the feed. According to KEGG annotation, the dominant metabolic pathways in the gut of A. japonicus were glycan biosynthesis and metabolism, nitrogen metabolism, and cysteine and methionine metabolism. This implies that the gut-colonized bacteria of A. japonicus are influenced by the surrounding water and the feed. In addition, the gut-colonized bacteria might be related to the growth and metabolism of A. japonicus.

Beyond Moco Biosynthesis-Moonlighting Roles of MoaE and MOCS2.

Molybdenum cofactor (Moco) biosynthesis requires iron, copper, and ATP. The Moco-containing enzyme sulfite oxidase catalyzes terminal oxidation in oxidative cysteine catabolism, and another Moco-containing enzyme, xanthine dehydrogenase, functions in purine catabolism. Thus, molybdenum enzymes participate in metabolic pathways that are essential for cellular detoxication and energy dynamics. Studies of the Moco biosynthetic enzymes MoaE (in the Ada2a-containing (ATAC) histone acetyltransferase complex) and MOCS2 have revealed that Moco biosynthesis and molybdenum enzymes align to regulate signaling and metabolism via control of transcription and translation. Disruption of these functions is involved in the onset of dementia and neurodegenerative disease. This review provides an overview of the roles of MoaE and MOCS2 in normal cellular processes and neurodegenerative disease, as well as directions for future research.

Comparison of Widely Targeted Metabolomics and Untargeted Metabolomics of Wild Ophiocordyceps sinensis

The authors of this paper conducted a comparative metabolomic analysis of Ophiocordyceps sinensis (OS), providing the metabolic profiles of the stroma (OSBSz) and sclerotia (OSBSh) of OS by widely targeted metabolomics and untargeted metabolomics. The results showed that 778 and 1449 metabolites were identified by the widely targeted metabolomics and untargeted metabolomics approaches, respectively. The metabolites in OSBSz and OSBSh are significantly differentiated; 71 and 96 differentially expressed metabolites were identified by the widely targeted metabolomics and untargeted metabolomics approaches, respectively. This suggests that these 71 metabolites (riboflavine, tripdiolide, bromocriptine, lumichrome, tetrahymanol, citrostadienol, etc.) and 96 metabolites (sancycline, vignatic acid B, pirbuterol, rubrophen, epalrestat, etc.) are potential biomarkers. 4-Hydroxybenzaldehyde, arginine, and lumichrome were common differentially expressed metabolites. Using the widely targeted metabolomics approach, the key pathways identified that are involved in creating the differentiation between OSBSz and OSBSh may be nicotinate and nicotinamide metabolism, thiamine metabolism, riboflavin metabolism, glycine, serine, and threonine metabolism, and arginine biosynthesis. The differentially expressed metabolites identified using the untargeted metabolomics approach were mainly involved in arginine biosynthesis, terpenoid backbone biosynthesis, porphyrin and chlorophyll metabolism, and cysteine and methionine metabolism. The purpose of this research was to provide support for the assessment of the differences between the stroma and sclerotia, to furnish a material basis for the evaluation of the physical effects of OS, and to provide a reference for the selection of detection methods for the metabolomics of OS.

Plasma and Urine Metabolomic Response to an Ultra-Processed Dietary Pattern: A Biomarker Discovery Analysis in a Domiciled Randomized Controlled Crossover Feeding Trial

ObjectivesTo identify metabolomic markers that differed between dietary patterns (DP) that are either high in or void of ultra-processed foods (UPFs) according to NOVA. MethodsA secondary analysis of a randomized, crossover, controlled feeding trial in which 20 domiciled, healthy participants (mean ± SD: 31 ± 7 years, BMI 22 ± 11.6, 50% female) consumed a UPF-DP (80% UPFs) and an unprocessed DP (UN-DP; 0% UPFs) for two weeks with no washout. DPs were matched for energy, macronutrients, total fiber, total sugar, and sodium; presented at 200% of energy requirements; and consumed ad libitum. Metabolite levels were measured in EDTA plasma at the end of each DP (wk 2) and in 24-hr and spot urine at wk 1 and 2, using untargeted liquid chromatography with high resolution/tandem mass spectrometry and annotated using Metabolon’s reference library and authentic standards. Metabolites (n = 1000 plasma, n = 1272 24-hr urine, and n = 1281 spot urine) with <80% missing data and coefficients of variation <30% were assigned minimum detected values, scaled to median of 1, and log2-transformed. Linear mixed models in SAS identified metabolites that differed between UPF-DP and UN-DP adjusted for trial, DP sequence, timepoint, and body weight changes, with a subject-specific random intercept and Benjamini-Hochberg multiple comparison correction. ResultsFor plasma, 183 metabolites differed between UPF-DP and UN-DP at wk 2. For 24-hr urine, 461 metabolites differed between UPF-DP and UN-DP at wk 1 and 2, 68 of which also differed at wk 1 and 2 for spot urine. Twenty metabolites consistently differed between UPF-DP and UN-DP at each timepoint and for each sample type. The sub pathways for these 20 metabolites included glutamate metabolism (n = 1 metabolite); ascorbate and aldarate metabolism (n = 1); benzoate metabolism (n = 2); methionine, cysteine, SAM and taurine metabolism (n = 2); secondary bile acid metabolism (n = 2); fatty acid dicarboxylate (n = 1); and plant-food components (n = 2); 9 could not be annotated. ConclusionsWe identified exogenous and endogenous metabolites, representing a range of metabolic pathways, that consistently differed between a UPF-DP and UN-DP. These candidate biomarkers of UPF intake require investigation in larger samples with dietary data sufficient for NOVA classification. Funding SourcesNCI, NIDDK.