Integrative Molecular Phenotyping
INTEGRATIVE MOLECULAR
PHENOTYPING
WHEELOCK LABORATORY
DEPARTMENT OF MEDICAL
BIOCHEMISTRY AND BIOPHYSICS
WHEELOCK LABORATORY
DEPARTMENT OF MEDICAL
BIOCHEMISTRY AND BIOPHYSICS
WHEELOCK LABORATORY
DEPARTMENT OF MEDICAL
BIOCHEMISTRY AND BIOPHYSICS
WHEELOCK LABORATORY
DEPARTMENT OF MEDICAL
BIOCHEMISTRY AND BIOPHYSICS
WHEELOCK LABORATORY
DEPARTMENT OF MEDICAL
BIOCHEMISTRY AND BIOPHYSICS
WHEELOCK LABORATORY

PubMed

Adenosine monophosphate enhances callus regeneration competence for de novo plant organogenesis

Wed, 11/10/2023 - 12:00
Mol Plant. 2023 Oct 9:S1674-2052(23)00318-0. doi: 10.1016/j.molp.2023.10.004. Online ahead of print.NO ABSTRACTPMID:37817411 | DOI:10.1016/j.molp.2023.10.004

Mendelian Randomization with Incomplete Measurements on the Exposure in the Hispanic Community Health Study/Study of Latinos

Wed, 11/10/2023 - 12:00
HGG Adv. 2023 Oct 9:100245. doi: 10.1016/j.xhgg.2023.100245. Online ahead of print.ABSTRACTMendelian randomization has been widely used to assess the causal effect of a heritable exposure variable on an outcome of interest, using genetic variants as instrumental variables. In practice, data on the exposure variable can be incomplete due to high cost of measurement and technical limits of detection. In this paper, we propose a valid and efficient method to handle both unmeasured and undetectable values of the exposure variable in one-sample Mendelian randomization analysis with individual-level data. We estimate the causal effect of the exposure variable on the outcome using maximum likelihood estimation and develop an expectation-maximization algorithm for the computation of the estimator. Simulation studies show that the proposed method performs well in making inference on the causal effect. We apply our method to the Hispanic Community Health Study/Study of Latinos, a community-based prospective cohort study, and estimate the causal effect of several metabolites on phenotypes of interest.PMID:37817410 | DOI:10.1016/j.xhgg.2023.100245

Compound Bacillus alleviates diarrhea by regulating gut microbes, metabolites, and inflammatory responses in pet cats

Wed, 11/10/2023 - 12:00
Anim Microbiome. 2023 Oct 10;5(1):49. doi: 10.1186/s42523-023-00270-8.ABSTRACTBACKGROUND: Pet cats frequently have diarrhea in their daily life. Bacillus has a protective role that has crucial beneficial functions on intestinal homeostasis. The aim of this research was to investigate the effects of the compound Bacillus on the prevention of diarrhea, microbiota and metabolism in pet cats. A total of 20 pet cats (1-2 years old, 3.91 ± 0.92 kg) were randomly divided into two groups and fed with a basal diet (Control group), or a basal diet supplemented with 3 × 109 CFU/kg compound Bacillus (Probiotics group). The experiment lasted 33 days.RESULTS: Results showed that the compound Bacillus significantly reduced the rate of soft stools and diarrhea in pet cats compared with the control group (P < 0.05, n = 10). Meanwhile, compared with the control group, the probiotics group significantly decreased the content of IL-1β and IL-6 and significantly increased IL-10 (P < 0.05, n = 6) in the serum. In addition, feeding probiotics significantly increased the abundance of p_Patescibacter and g_Plectosphaerella, decreased the abundance of p_Firmicutes, p_Gemmatimonadetes, g_Ruminococcaceae_UCG-005, g_Ascochytahe and g_Saccharomyces in the feces of the pet cats (P < 0.05, n = 6). And it also can significantly increase the content of total SCFAs, acetic acid and butyric acid in the feces (P < 0.05, n = 6). The fecal and serum metabolomics analyses revealed that most fecal and serum compounds were involved in metabolism, particularly in chemical structure transformation maps and amino acid metabolism. Also, eugenitol and methyl sulfate were the most significantly increased serum metabolites, and log2FC were 38.73 and 37.12, respectively. Pearson's correlation analysis showed that changes in serum metabolism and fecal microbiota were closely related to immune factors. There was also a strong correlation between serum metabolites and microbiota composition.CONCLUSIONS: The results of this research highlight the potential of the compound Bacillus as a dietary supplement to alleviate diarrhea in pet cats.PMID:37817260 | DOI:10.1186/s42523-023-00270-8

Exploring the potential mechanism of Xuebijing injection against sepsis based on metabolomics and network pharmacology

Tue, 10/10/2023 - 12:00
Anal Biochem. 2023 Oct 8:115332. doi: 10.1016/j.ab.2023.115332. Online ahead of print.ABSTRACTSepsis is a major contributor to the death of critically ill patients globally, in which metabolic disturbance is observed. Xuebijing injection (XBJ), a well-known traditional Chinese medicine, has received approval by the State Food and Drug Administration (SFDA) of China owing to its satisfactory clinical therapeutic effect. Nowadays, it has been applied clinically to the treatment of sepsis, but its effect on metabolic disorders remains unclear. In the present study, we sought to explore its underlying mechanism by employing a combination of network pharmacology and metabolomics. Initially, its protective effects were validated using a sepsis rat model created through cecal ligation puncture (CLP). Subsequently, the metabonomic strategy was utilized to discriminate the differential metabolic markers. Meanwhile, a comprehensive view of the potential ingredient-target-disease network was constructed based on a network pharmacology analysis. Next, the network diagram was constructed by integrating the results of network pharmacology and metabonomics. Finally, qRT-PCR together with Western blot was used to validate the expression levels of the associated genes. Based on our findings, we identified 34 differential metabolites in the sepsis group and 26 distinct metabolites in the XBJ group, with 8 common biological metabolites predominantly associated with arginine and proline metabolism. Through comprehensive analysis, we identified 21 genes that regulate metabolites, and qRT-PCR validation was conducted on six of these genes in both liver and kidney tissues. Additionally, XBJ demonstrated the capability to inhibit the activation of the NF-kB signaling pathway in both liver and kidney tissues, leading to a reduction in the occurrence of inflammatory responses. In summary, our study has validated the complexity of the natural compounds within XBJ and elucidated their potential mechanisms for addressing CLP-induced metabolic disturbances. This work contributes to our understanding of the bioactive compounds and their associated targets, providing insights into the potential molecular mechanisms involved.PMID:37816419 | DOI:10.1016/j.ab.2023.115332

Very-long-chain fatty acids are crucial to neuronal polarity by providing sphingolipids to lipid rafts

Tue, 10/10/2023 - 12:00
Cell Rep. 2023 Oct 2:113195. doi: 10.1016/j.celrep.2023.113195. Online ahead of print.ABSTRACTFatty acids have long been considered essential to brain development; however, the involvement of their synthesis in nervous system formation is unclear. We generate mice with knockout of GPSN2, an enzyme for synthesis of very-long-chain fatty acids (VLCFAs) and investigate the effects. Both GPSN2-/- and GPSN2+/- mice show abnormal neuronal networks as a result of impaired neuronal polarity determination. Lipidomics of GPSN2-/- embryos reveal that ceramide synthesis is specifically inhibited depending on FA length; namely, VLCFA-containing ceramide is reduced. We demonstrate that lipid rafts are highly enriched in growth cones and that GPSN2+/- neurons lose gangliosides in their membranes. Application of C24:0 ceramide, but not C16:0 ceramide or C24:0 phosphatidylcholine, to GPSN2+/- neurons rescues both neuronal polarity determination and lipid-raft density in the growth cone. Taken together, our results indicate that VLCFA synthesis contributes to physiological neuronal development in brain network formation, in particular neuronal polarity determination through the formation of lipid rafts.PMID:37816355 | DOI:10.1016/j.celrep.2023.113195

Multi-omics analysis reveals the toxic mechanism of ammonia-enhanced Microcystis aeruginosa exposure causing liver fat deposition and muscle nutrient loss in zebrafish

Tue, 10/10/2023 - 12:00
J Hazard Mater. 2023 Sep 26;461:132631. doi: 10.1016/j.jhazmat.2023.132631. Online ahead of print.ABSTRACTMicrocystis aeruginosa and ammonia pollution are two important environmental stress factors in water eutrophication. Herein, we simulated environmental conditions to investigate the effects of chronic exposure (single and combined) to M. aeruginosa and total ammonia nitrogen (TAN) on lipid metabolism and muscle quality in zebrafish. Our results showed that M. aeruginosa and TAN significantly induced lipid deposition and tissue damage in the liver of zebrafish. Liver transcriptomic analysis revealed that M. aeruginosa and TAN disrupted the balance in lipid synthesis, decomposition, and transport, ultimately leading to hepatic lipid accumulation. Moreover, exposure to M. aeruginosa or TAN alone resulted in decreased crude protein content and increased lipid content in muscle, as well as disrupted muscle fatty acid composition. Metabolomic analysis of muscle revealed significant alterations in metabolites such as glycerolipids, glycerophospholipids and fatty acids. The co-exposure of M. aeruginosa and TAN had a more significant effect on liver lipid dysfunction and muscle quality deterioration in zebrafish. These findings provide valuable insights into the potential risks and hazards of M. aeruginosa and TAN in eutrophic water bodies subject to Microcystis blooms, and can help inform effective strategies for monitoring and managing these toxins in aquatic ecosystems.PMID:37816294 | DOI:10.1016/j.jhazmat.2023.132631

A diagnostic electrochemical aptasensor development for sCD80 protein detection in human serum

Tue, 10/10/2023 - 12:00
Biosens Bioelectron. 2023 Sep 28;242:115696. doi: 10.1016/j.bios.2023.115696. Online ahead of print.ABSTRACTElevating soluble CD80 (sCD80) in human serum is a natural response to autoimmune diseases such as rheumatoid arthritis (RA). The level of sCD80 is associated with RA development and prognosis; therefore, it is potentially used as a biomarker. sCD80 is commonly measured in human serum using immunoassays (e.g., ELISA) with multiple drawbacks, mainly cross-reactivity. Aptamer-based biosensors (aptasensors) development for quantifying and detecting different biological molecules demonstrates applicability in next-generation medicine and biomarker detection. Herein, we selected a specific aptamer for sCD80 by conventional in-vitro selection process (SELEX) with the high-affinity aptamer (Kd = 47.69 nM). A sensitive aptasensor, for the first time, was developed on a screen-printed gold electrode (AuSPE) platform compatible with easy-to-use label-free electrochemical impedance spectroscopy. The immobilization of the aptamer on the gold surface and the presence of sCD80 in a complex with the aptamer were characterized by photo-induced force microscopy, which revealed the uniform assembly of the aptamer monolayer and the distribution of sCD80 on the electrode surface. The developed aptasensor showed a linear performance (0.025-10.0 nM of protein) with a detection limit of 8.0 pM. Furthermore, the aptasensor was tested in a biological matrix, where a linear signal was observed for the increased amount of spiked sCD80 (R2 = 0.9887). The recovery of the spiked amounts ranged from 105 to 125% with coefficient of variation (CV%) <7%, which supported the applicability of this sensor in detecting sCD80 for diagnosis.PMID:37816286 | DOI:10.1016/j.bios.2023.115696

The metabolic potential of inflammatory and insulinaemic dietary patterns and risk of type 2 diabetes

Tue, 10/10/2023 - 12:00
Diabetologia. 2023 Oct 11. doi: 10.1007/s00125-023-06021-3. Online ahead of print.ABSTRACTAIMS/HYPOTHESIS: Diets with higher inflammatory and insulinaemic potential have been associated with an increased risk of type 2 diabetes. However, it remains unknown whether plasma metabolomic profiles related to proinflammatory/hyperinsulinaemic diets and to inflammatory/insulin biomarkers are associated with type 2 diabetes risk.METHODS: We analysed 6840 participants from the Nurses' Health Study and Health Professionals Follow-up Study to identify the plasma metabolome related to empirical dietary inflammatory pattern (EDIP), empirical dietary index for hyperinsulinemia (EDIH), four circulating inflammatory biomarkers and C-peptide. Dietary intakes were assessed using validated food frequency questionnaires. Plasma metabolomic profiling was conducted by LC-MS/MS. Metabolomic signatures were derived using elastic net regression. Multivariable Cox regression was used to examine associations of the metabolomic profiles with type 2 diabetes risk.RESULTS: We identified 27 metabolites commonly associated with both EDIP and inflammatory biomarker z score and 21 commonly associated with both EDIH and C-peptide. Higher metabolomic dietary inflammatory potential (MDIP), reflecting higher metabolic potential of both an inflammatory dietary pattern and circulating inflammatory biomarkers, was associated with higher type 2 diabetes risk. The HR comparing highest vs lowest quartiles of MDIP was 3.26 (95% CI 2.39, 4.44). We observed a strong positive association with type 2 diabetes risk for the metabolomic signature associated with EDIP-only (HR 3.75; 95% CI 2.71, 5.17) or inflammatory biomarkers-only (HR 4.07; 95% CI 2.91, 5.69). In addition, higher metabolomic dietary index for hyperinsulinaemia (MDIH), reflecting higher metabolic potential of both an insulinaemic dietary pattern and circulating C-peptide, was associated with greater type 2 diabetes risk (HR 3.00; 95% CI 2.22, 4.06); further associations with type 2 diabetes were HR 2.79 (95% CI 2.07, 3.76) for EDIH-only signature and HR 3.89 (95% CI 2.82, 5.35) for C-peptide-only signature. The diet scores were significantly associated with risk, although adjustment for the corresponding metabolomic signature scores attenuated the associations with type 2 diabetes, these remained significant.CONCLUSIONS/INTERPRETATION: The metabolomic signatures reflecting proinflammatory or hyperinsulinaemic diets and related biomarkers were positively associated with type 2 diabetes risk, supporting that these dietary patterns may influence type 2 diabetes risk via the regulation of metabolism.PMID:37816982 | DOI:10.1007/s00125-023-06021-3

Rawi Ramautar and David D. Y. Chen (Eds.): Capillary electrophoresis-mass spectrometry for proteomics and metabolomics: principles and applications

Tue, 10/10/2023 - 12:00
Anal Bioanal Chem. 2023 Oct 10. doi: 10.1007/s00216-023-04980-5. Online ahead of print.NO ABSTRACTPMID:37816949 | DOI:10.1007/s00216-023-04980-5

Determination of tryptophan and its indole metabolites in follicular fluid of women with diminished ovarian reserve

Tue, 10/10/2023 - 12:00
Sci Rep. 2023 Oct 10;13(1):17124. doi: 10.1038/s41598-023-44335-9.ABSTRACTTryptophan (TRP) and its indole metabolites exhibit numerous biological effects, especially their antioxidant properties. This study used untargeted metabolomics in conjunction with targeted metabolomics to investigate the differential expression of tryptophan and its indole metabolites in follicular fluid (FF) of diminished ovarian reserve (DOR) and normal ovarian reserve (NOR) populations. This study included patients with DOR (n = 50) and females with NOR (n = 35) who received in vitro fertilization and embryo transfer. Untargeted metabolomics suggests that diminished ovarian reserve affects the metabolic profile of FF, TRP and indole metabolites were significantly down-regulated in the DOR group. Targeted metabolomics quantification revealed that the levels of TRP, IPA and IAA in the FF of the DOR group were significantly lower than those of the NOR group (P < 0.01). The concentration of TRP in FF is positively correlated with the available embryo rate in NOR females. These results provide data support to explore the pathogenesis of DOR and to look for new biomarkers and ovarian protectors. Additionally, alterations in TRP and its indole metabolites in FF may indirectly reflect the interaction between intestinal flora and the follicular microenvironment.PMID:37816920 | DOI:10.1038/s41598-023-44335-9

Positive regulation of oxidative phosphorylation by nuclear myosin 1 protects cells from metabolic reprogramming and tumorigenesis in mice

Tue, 10/10/2023 - 12:00
Nat Commun. 2023 Oct 10;14(1):6328. doi: 10.1038/s41467-023-42093-w.ABSTRACTMetabolic reprogramming is one of the hallmarks of tumorigenesis. Here, we show that nuclear myosin 1 (NM1) serves as a key regulator of cellular metabolism. NM1 directly affects mitochondrial oxidative phosphorylation (OXPHOS) by regulating mitochondrial transcription factors TFAM and PGC1α, and its deletion leads to underdeveloped mitochondria inner cristae and mitochondrial redistribution within the cell. These changes are associated with reduced OXPHOS gene expression, decreased mitochondrial DNA copy number, and deregulated mitochondrial dynamics, which lead to metabolic reprogramming of NM1 KO cells from OXPHOS to aerobic glycolysis.This, in turn, is associated with a metabolomic profile typical for cancer cells, namely increased amino acid-, fatty acid-, and sugar metabolism, and increased glucose uptake, lactate production, and intracellular acidity. NM1 KO cells form solid tumors in a mouse model, suggesting that the metabolic switch towards aerobic glycolysis provides a sufficient carcinogenic signal. We suggest that NM1 plays a role as a tumor suppressor and that NM1 depletion may contribute to the Warburg effect at the onset of tumorigenesis.PMID:37816864 | DOI:10.1038/s41467-023-42093-w

Antcin-B, a phytosterol-like compound from Taiwanofungus camphoratus inhibits SARS-CoV-2 3-chymotrypsin-like protease (3CL<sup>Pro</sup>) activity in silico and in vitro

Tue, 10/10/2023 - 12:00
Sci Rep. 2023 Oct 10;13(1):17106. doi: 10.1038/s41598-023-44476-x.ABSTRACTDespite the remarkable development of highly effective vaccines, including mRNA-based vaccines, within a limited timeframe, coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is not been entirely eradicated. Thus, it is crucial to identify new effective anti-3CLPro compounds, pivotal for the replication of SARS-CoV-2. Here, we identified an antcin-B phytosterol-like compound from Taiwanofungus camphoratus that targets 3CLPro activity. MTT assay and ADMET prediction are employed for assessing potential cytotoxicity. Computational molecular modeling was used to screen various antcins and non-antcins for binding affinity and interaction type with 3CLPro. Further, these compounds were subjected to study their inhibitory effects on 3CLPro activity in vitro. Our results indicate that antcin-B has the best binding affinity by contacting residues like Leu141, Asn142, Glu166, and His163 via hydrogen bond and salt bridge and significantly inhibits 3CLPro activity, surpassing the positive control compound (GC376). The 100 ns molecular dynamics simulation studies showed that antcin-B formed consistent, long-lasting water bridges with Glu166 for their inhibitory activity. In summary, antcin-B could be useful to develop therapeutically viable drugs to inhibit SARS-CoV-2 replication alone or in combination with medications specific to other SARS-CoV-2 viral targets.PMID:37816832 | DOI:10.1038/s41598-023-44476-x

Unexpected metabolic rewiring of CO<sub>2</sub> fixation in H<sub>2</sub>-mediated materials-biology hybrids

Tue, 10/10/2023 - 12:00
Proc Natl Acad Sci U S A. 2023 Oct 17;120(42):e2308373120. doi: 10.1073/pnas.2308373120. Epub 2023 Oct 10.ABSTRACTA hybrid approach combining water-splitting electrochemistry and H2-oxidizing, CO2-fixing microorganisms offers a viable solution for producing value-added chemicals from sunlight, water, and air. The classic wisdom without thorough examination to date assumes that the electrochemistry in such a H2-mediated process is innocent of altering microbial behavior. Here, we report unexpected metabolic rewiring induced by water-splitting electrochemistry in H2-oxidizing acetogenic bacterium Sporomusa ovata that challenges such a classic view. We found that the planktonic S. ovata is more efficient in utilizing reducing equivalent for ATP generation in the materials-biology hybrids than cells grown with H2 supply, supported by our metabolomic and proteomic studies. The efficiency of utilizing reducing equivalents and fixing CO2 into acetate has increased from less than 80% of chemoautotrophy to more than 95% under electroautotrophic conditions. These observations unravel previously underappreciated materials' impact on microbial metabolism in seemingly simply H2-mediated charge transfer between biotic and abiotic components. Such a deeper understanding of the materials-biology interface will foster advanced design of hybrid systems for sustainable chemical transformation.PMID:37816063 | DOI:10.1073/pnas.2308373120

ZNT1 and Zn2+ control TLR4 and PD-L1 endocytosis in macrophage to improve chemotherapy efficacy against liver tumor

Tue, 10/10/2023 - 12:00
Hepatology. 2023 Oct 9. doi: 10.1097/HEP.0000000000000629. Online ahead of print.ABSTRACTBACKGROUND AIMS: Hepatocellular carcinoma (HCC) is closely associated with inflammation and immune modulation, and combined chemotherapy with other strategies is under extensive investigation to achieve better efficacy. HCC is accompanied by zinc deficiency. This study aims to understand how zinc could affect macrophage function and its application for HCC therapy.APPROACH RESULTS: Zn2+ and the zinc transporter 1 (ZNT1, SLC30A1) were markedly reduced in intrahepatic macrophages from HCC patients and mouse liver tumors. Lower ZNT1 expression was associated with higher IL-6 production and shorter survival time in HCC patients. Critically, ZNT1 regulated endosomal Zn2+ levels for endocytosis of TLR4 and PD-L1, thereby decreasing macrophage-induced inflammation and immunosuppression to protect from liver tumors. Myeloid-specific deletion of ZNT1 in mice increased chronic inflammation, liver fibrosis, tumor numbers, and size. Notably, zinc supplementation could reduce inflammation and surface PD-L1 expression in macrophages with the increased CD8+ T cell cytotoxicity, which synergized the anti-tumor efficacy of Sorafenib/Lenvatinib.CONCLUSIONS: Our study proposes a new concept that ZNT1 and zinc regulate endosome endocytosis to maintain surface receptors and zinc supplements might be synergized with chemotherapy to treat inflammation-associated tumors, especially those containing PD-L1+ myeloid cells.PMID:37816045 | DOI:10.1097/HEP.0000000000000629

Serum metabolomics of treatment response in myasthenia gravis

Tue, 10/10/2023 - 12:00
PLoS One. 2023 Oct 10;18(10):e0287654. doi: 10.1371/journal.pone.0287654. eCollection 2023.ABSTRACTOBJECTIVE: High-dose prednisone use, lasting several months or longer, is the primary initial therapy for myasthenia gravis (MG). Upwards of a third of patients do not respond to treatment. Currently no biomarkers can predict clinical responsiveness to corticosteroid treatment. We conducted a discovery-based study to identify treatment responsive biomarkers in MG using sera obtained at study entry to the thymectomy clinical trial (MGTX), an NIH-sponsored randomized, controlled study of thymectomy plus prednisone versus prednisone alone.METHODS: We applied ultra-performance liquid chromatography coupled with electro-spray quadrupole time of flight mass spectrometry to obtain comparative serum metabolomic and lipidomic profiles at study entry to correlate with treatment response at 6 months. Treatment response was assessed using validated outcome measures of minimal manifestation status (MMS), MG-Activities of Daily Living (MG-ADL), Quantitative MG (QMG) score, or a strictly defined composite measure of response.RESULTS: Increased serum levels of phospholipids were associated with treatment response as assessed by QMG, MMS, and the Responders classification, but all measures showed limited overlap in metabolomic profiles, in particular the MG-ADL. A panel including histidine, free fatty acid (13:0), γ-cholestenol and guanosine was highly predictive of the strictly defined treatment response measure. The AUC in Responders' prediction for these markers was 0.90 irrespective of gender, age, thymectomy or baseline prednisone use. Pathway analysis suggests that xenobiotic metabolism could play a major role in treatment resistance. There was no association with outcome and gender, age, thymectomy or baseline prednisone use.INTERPRETATION: We have defined a metabolomic and lipidomic profile that can now undergo validation as a treatment predictive marker for MG patients undergoing corticosteroid therapy. Metabolomic profiles of outcome measures had limited overlap consistent with their assessing distinct aspects of treatment response and supporting unique biological underpinning for each outcome measure. Interindividual variation in prednisone metabolism may be a determinate of how well patients respond to treatment.PMID:37816000 | DOI:10.1371/journal.pone.0287654

Assessing Metabolic Differences Associated with Exposure to Polybrominated Biphenyl and Polychlorinated Biphenyls in the Michigan PBB Registry

Tue, 10/10/2023 - 12:00
Environ Health Perspect. 2023 Oct;131(10):107005. doi: 10.1289/EHP12657. Epub 2023 Oct 10.ABSTRACTBACKGROUND: Polybrominated biphenyls (PBB) and polychlorinated biphenyls (PCB) are persistent organic pollutants with potential endocrine-disrupting effects linked to adverse health outcomes.OBJECTIVES: In this study, we utilize high-resolution metabolomics (HRM) to identify internal exposure and biological responses underlying PCB and multigenerational PBB exposure for participants enrolled in the Michigan PBB Registry.METHODS: HRM profiling was conducted on plasma samples collected from 2013 to 2014 from a subset of participants enrolled in the Michigan PBB Registry, including 369 directly exposed individuals (F0) who were alive when PBB mixtures were accidentally introduced into the food chain and 129 participants exposed to PBB in utero or through breastfeeding, if applicable (F1). Metabolome-wide association studies were performed for PBB-153 separately for each generation and ΣPCB (PCB-118, PCB-138, PCB-153, and PCB-180) in the two generations combined, as both had direct PCB exposure. Metabolite and metabolic pathway alterations were evaluated following a well-established untargeted HRM workflow.RESULTS: Mean levels were 1.75 ng/mL [standard deviation (SD): 13.9] for PBB-153 and 1.04 ng/mL (SD: 0.788) for ΣPCB. Sixty-two and 26 metabolic features were significantly associated with PBB-153 in F0 and F1 [false discovery rate (FDR) p<0.2], respectively. There were 2,861 features associated with ΣPCB (FDR p<0.2). Metabolic pathway enrichment analysis using a bioinformatics tool revealed perturbations associated with ΣPCB in numerous oxidative stress and inflammation pathways (e.g., carnitine shuttle, glycosphingolipid, and vitamin B9 metabolism). Metabolic perturbations associated with PBB-153 in F0 were related to oxidative stress (e.g., pentose phosphate and vitamin C metabolism) and in F1 were related to energy production (e.g., pyrimidine, amino sugars, and lysine metabolism). Using authentic chemical standards, we confirmed the chemical identity of 29 metabolites associated with ΣPCB levels (level 1 evidence).CONCLUSIONS: Our results demonstrate that serum PBB-153 is associated with alterations in inflammation and oxidative stress-related pathways, which differed when stratified by generation. We also found that ΣPCB was associated with the downregulation of important neurotransmitters, serotonin, and 4-aminobutanoate. These findings provide novel insights for future investigations of molecular mechanisms underlying PBB and PCB exposure on health. https://doi.org/10.1289/EHP12657.PMID:37815925 | DOI:10.1289/EHP12657

MYC is a regulator of androgen receptor inhibition-induced metabolic requirements in prostate cancer

Tue, 10/10/2023 - 12:00
Cell Rep. 2023 Oct 9;42(10):113221. doi: 10.1016/j.celrep.2023.113221. Online ahead of print.ABSTRACTAdvanced prostate cancers are treated with therapies targeting the androgen receptor (AR) signaling pathway. While many tumors initially respond to AR inhibition, nearly all develop resistance. It is critical to understand how prostate tumor cells respond to AR inhibition in order to exploit therapy-induced phenotypes prior to the outgrowth of treatment-resistant disease. Here, we comprehensively characterize the effects of AR blockade on prostate cancer metabolism using transcriptomics, metabolomics, and bioenergetics approaches. The metabolic response to AR inhibition is defined by reduced glycolysis, robust elongation of mitochondria, and increased reliance on mitochondrial oxidative metabolism. We establish DRP1 activity and MYC signaling as mediators of AR-blockade-induced metabolic phenotypes. Rescuing DRP1 phosphorylation after AR inhibition restores mitochondrial fission, while rescuing MYC restores glycolytic activity and prevents sensitivity to complex I inhibition. Our study provides insight into the regulation of treatment-induced metabolic phenotypes and vulnerabilities in prostate cancer.PMID:37815914 | DOI:10.1016/j.celrep.2023.113221

Whole-genome sequence and mass spectrometry study of the snow blight fungus Phacidium infestans (Karsten) DSM 5139 growing at freezing temperatures

Tue, 10/10/2023 - 12:00
Mol Genet Genomics. 2023 Oct 10. doi: 10.1007/s00438-023-02073-7. Online ahead of print.ABSTRACTPhacidium infestans (synonym Gremmenia infestans) is a significant pathogen that impacts Pinus species across the northern regions of Europe and Asia. This study introduces the genome sequence of P. infestans Karsten DSM 5139 (Phain), obtained through Pacbio technology. The assembly resulted in 44 contigs, with a total genome size of 36,805,277 bp and a Guanine-Cytosine content of 46.4%. Genome-mining revealed numerous putative biosynthetic gene clusters that code for virulence factors and fungal toxins. The presence of the enzyme pisatin demethylase was indicative of the potential of Phain to detoxify its environment from the terpenoid phytoalexins produced by its host as a defense mechanism. Proteomic analysis revealed the potential survival strategies of Phain under the snow, which included the production of antifreeze proteins, trehalose synthesis enzymes, desaturases, proteins related to elongation of very long-chain fatty acids, and stress protein responses. Study of protein GH11 endoxylanase expressed in Escherichia coli showed an acidic optimum pH (pH 5.0) and a low optimum temperature (45 °C), which is reflective of the living conditions of the fungus. Mass spectrometry analysis of the methanol extract of Phain, incubated at - 3 °C and 22 °C, revealed differences in the produced metabolites. Both genomic and mass spectrometry analyses showed the ability of Phain to adapt its metabolic processes and secretome to freezing temperatures through the production of osmoprotectant and cryoprotectant metabolites. This comprehensive exploration of Phain's genome sequence, proteome, and secretome not only advances our understanding of its unique adaptive mechanisms but also expands the possibilities of biotechnological applications.PMID:37815644 | DOI:10.1007/s00438-023-02073-7

Exploring the mechanism of clomiphene citrate to improve ovulation disorder in PCOS rats based on follicular fluid metabolomics

Tue, 10/10/2023 - 12:00
Naunyn Schmiedebergs Arch Pharmacol. 2023 Oct 10. doi: 10.1007/s00210-023-02750-9. Online ahead of print.ABSTRACTTo examine the effects of clomiphene citrate (CC) on follicular fluid metabolites and related metabolic pathways in rats with polycystic ovary syndrome (PCOS) using non-targeted metabolomics and determine how CC treats ovulation disorder in PCOS. The Sprague Dawley rats were randomly divided into control, model, and CC groups. A PCOS model was established with letrozole. Body weight, ovarian weight, estrus cycles, serum hormone levels, and ovary histopathology of the rats were collected for further evaluation. Moreover, through ultra-performance liquid chromatography-mass spectrometry, the study of follicular fluid metabolites revealed the mechanism of action of CC. CC reduced ovarian weight and regulated estrous cycles and serum hormone levels in PCOS rats but did not affect their body weight. Moreover, the metabolomic results showed that CC adjusted 153 metabolites, among which 16 cross metabolites like testosterone, androstenedione, 17α-hydroxyprogesterone, and cholic acid were considered as potential biomarkers for CC to improve ovulation disorders in PCOS rats. Kyoto Encyclopedia of Genes and Genomes pathway enrichment also showed that the CC group mainly engaged in tryptophan metabolism and steroid hormone biosynthesis. CC can improve ovulation disorders in rats, and its mechanism is related to the regulation of the secretion of serum hormone and follicular fluid metabolites and the amelioration of multi-metabolic pathways.PMID:37815607 | DOI:10.1007/s00210-023-02750-9

Metabolite diversity among representatives of divergent <em>Prochlorococcus</em> ecotypes

Tue, 10/10/2023 - 12:00
mSystems. 2023 Oct 10:e0126122. doi: 10.1128/msystems.01261-22. Online ahead of print.ABSTRACTThe euphotic zone of the surface ocean contains distinct physical-chemical regimes that vary in light and nutrient concentrations as an inverse function of depth. The most numerous phytoplankter of the mid- and low-latitude ocean is the picocyanobacterium Prochlorococcus, which consists of ecologically distinct subpopulations (i.e., "ecotypes"). Ecotypes have different temperature, light, and nutrient optima and display distinct relative abundances along gradients of these niche dimensions. As a primary producer, Prochlorococcus fixes and releases organic carbon to neighboring microbes as part of the microbial loop. However, little is known about the specific molecules Prochlorococcus accumulates and releases or how these processes vary among its ecotypes. Here, we characterize the metabolite diversity of Prochlorococcus by profiling three ecologically distinct cultured strains: MIT9301, representing a high-light-adapted ecotype dominating shallow tropical and sub-tropical waters; MIT0801, representing a low-light-adapted ecotype found throughout the euphotic zone; and MIT9313, representing a low-light-adapted ecotype relatively most abundant at the base of the euphotic zone. In both intracellular and extracellular metabolite profiles, we observe striking differences across strains in the accumulation and release of molecules, such as the DNA methylating agent S-adenosyl-methionine (intracellular) and the branched-chain amino acids (intracellular) and their precursors (extracellular). While some differences reflect variable genome content across the strains, others likely reflect variable regulation of conserved pathways. In the extracellular profiles, we identify molecules such as pantothenic acid and aromatic amino acids that may serve as currencies in Prochlorococcus' interactions with neighboring microbes and, therefore, merit further investigation. IMPORTANCE Approximately half of the annual carbon fixation on Earth occurs in the surface ocean through the photosynthetic activities of phytoplankton such as the ubiquitous picocyanobacterium Prochlorococcus. Ecologically distinct subpopulations (or ecotypes) of Prochlorococcus are central conduits of organic substrates into the ocean microbiome, thus playing important roles in surface ocean production. We measured the chemical profile of three cultured ecotype strains, observing striking differences among them that have implications for the likely chemical impact of Prochlorococcus subpopulations on their surroundings in the wild. Subpopulations differ in abundance along gradients of temperature, light, and nutrient concentrations, suggesting that these chemical differences could affect carbon cycling in different ocean strata and should be considered in models of Prochlorococcus physiology and marine carbon dynamics.PMID:37815355 | DOI:10.1128/msystems.01261-22

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