The Britz-McKibbin Laboratory
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No publisher2024/03/26 07:54:35 GMT-4News ItemJacqueline Burton
https://britz.mcmaster.ca/people/jacqueline-burton
No publisherPersonElements and omega-3 fatty acids in fishes along a large, dammed river
https://britz.mcmaster.ca/publications/articlereference.2024-01-11.0794504612
Damming of a river can trap and elevate levels of sediment-bound elements and alter food web dynamics in created reservoirs. It follows that dams may alter how elements and other nutrients, like the beneficial omega-3 fatty acids (n-3 FAs) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are accumulated in fish and thus the chemical composition of species above and below this barrier to migration. This study examined the spatial and species differences in contaminants and nutrients in fish from the Wolastoq | Saint John River (New Brunswick, Canada) in association with a large hydroelectric dam (Mactaquac Generating Station; MQGS), a river which supports both recreational fisheries and subsistence fishing by Indigenous communities. In 2020 and 2021, Smallmouth Bass, Yellow Perch, American Eel, and Striped Bass were collected from locations upstream (reservoir and river) and downstream of the MQGS and analyzed for mercury (Hg) and 30 other trace elements, n-3 FAs, δ 15 N, and δ 13 C. Fish from the reservoir were highest in the beneficial elements P, S, and K, while fish from upstream of the reservoir had lower levels of toxic elements, including Hg. The dam appeared to alter food web dynamics, as fish from the reservoir and immediately downstream of the dam had higher δ 15 N and reservoir fish were depleted in δ 13 C. DHA and Hg were positively corelated with δ 15 N, and EPA in Smallmouth Bass was higher in sites where fish had higher δ 13 C. Overall, this study suggests that the dam altered food web dynamics and the uptake of contaminants and nutrients by fish, and that location and species are important factors when examining the risks and benefits of consuming wild fish from a system impacted by a large dam.No publisher2024/01/11 07:46:09 GMT-5Article ReferenceA novel multi-ancestry proteome-wide Mendelian randomization study implicates extracellular proteins, tubular cells, and fibroblasts in estimated glomerular filtration rate regulation
https://britz.mcmaster.ca/publications/articlereference.2024-01-11.8639231430
Estimated glomerular filtration rate (eGFR) impacts the concentration of plasma biomarkers confounding biomarker association studies of eGFR with reverse causation. To identify biomarkers causally associated with eGFR, we performed a proteome-wide Mendelian randomization study. Genetic variants nearby biomarker coding genes were tested for association with plasma concentration of 1,161 biomarkers in a multi-ancestry sample of 12,066 participants from the Prospective Urban and Rural Epidemiological (PURE) study. Using two-sample Mendelian randomization, individual variants’ effects on biomarker concentration were correlated with their effects on eGFR and kidney traits from published genome-wide association studies (GWAS). Genetically altered concentrations of 22 biomarkers were associated with eGFR above a Bonferroni-corrected significance threshold. Five biomarkers were previously identified by GWAS ( UMOD , FGF5, LGALS7, NINJ1, COL18A1 ). Nine biomarkers were within 1 Mb of the lead GWAS variant but the gene for the biomarker was unidentified as the candidate for the GWAS signal ( INHBC, TNFRSF11A, TCN2, PXN1, PRTN3, PSMD9, TFPI, ITGB6, CA3 ). Single-cell transcriptomic data indicated the 22 biomarkers are expressed in kidney tubules , collecting duct , fibroblasts, and immune cells . Pathway analysis showed significant enrichment of identified biomarkers in the extracellular kidney parenchyma. Thus, using genetic regulators of biomarker concentration via proteome-wide Mendelian randomization, we identified 22 biomarkers that appear to causally impact eGFR in either a beneficial or adverse manner. The current study provides rationale for novel therapeutic targets for eGFR and emphasized a role for extracellular proteins produced by tubular cells and fibroblasts for impacting eGFR.No publisher2024/01/11 07:43:54 GMT-5Article ReferenceLipidomic studies reveal two specific circulating phosphatidylcholines as surrogate biomarkers of the omega-3 index
https://britz.mcmaster.ca/publications/articlereference.2024-01-11.6533631772
Optimal dietary intake of omega-3 long-chain polyunsaturated fatty acids (n3-LCPUFAs) is critical to human health across the lifespan. However, omega-3 index (O3I) determination is not routinely assessed due to complicated procedures for n3-LCPUFA analysis from the phospholipid (PL) fraction of erythrocytes. Herein, a high-throughput method for lipidomics based on multisegment injection-nonaqueous capillary electrophoresis-mass spectrometry was applied to identify circulating PLs as surrogate biomarkers of O3I in two randomized placebo-controlled trials. An untargeted lipidomic data workflow using a subgroup analysis of serum extracts from sunflower oil versus high-dose fish oil (FO)-supplemented participants revealed that ingested n3-LCPUFAs were primarily distributed as their phosphatidylcholines (PCs) relative to other PL classes. In both high-dose FO (5.0 g/day) and EPA-only trials (3.0 g/day), PC (16:0_20:5) was the most responsive PL, whereas PC (16:0_22:6) was selective to DHA-only supplementation. We also demonstrated that the sum concentration of both these PCs in fasting serum or plasma samples was positively correlated to the O3I following FO ( r = 0.708, P = 1.02 × 10 −11 , n = 69) and EPA- or DHA-only supplementation ( r = 0.768, P = 1.01 × 10 −33 , n = 167). Overall, DHA was more effective in improving the O3I (ΔO3I = 4.90 ± 1.33%) compared to EPA (ΔO3I = 2.99 ± 1.19%) in young Canadian adults who had a poor nutritional status with an O3I (3.50 ± 0.68%) at baseline. Our method enables the rapid assessment of the O3I by directly measuring two circulating PC species in small volumes of blood, which may facilitate screening applications for population and precision health.No publisher2024/01/11 07:39:29 GMT-5Article ReferenceExpanding Lipidomic Coverage in Multisegment Injection-Nonaqueous Capillary Electrophoresis-Mass Spectrometry via a Convenient and Quantitative Methylation Strategy
https://britz.mcmaster.ca/publications/articlereference.2024-01-11.5008906254
Orthogonal separation techniques coupled to high-resolution mass spectrometry (MS) are required for characterization of the human lipidome given its inherent chemical and structural complexity. However, electrophoretic separations remain largely unrecognized in contemporary lipidomics research as compared to various chromatographic and ion mobility methods. Herein, we introduce a novel derivatization protocol based on 3-methyl-1-p-tolyltriazene (MTT) as a safer alternative to diazomethane for quantitative phospholipid (PL) methylation (~ 90%), which enables their rapid analysis by multisegment injection-nonaqueous capillary electrophoresis-mass spectrometry (MSI-NACE-MS). Isobaric interferences and ion suppression effects were minimized by performing an initial reaction using 9-fluorenylmethyoxycarbonyl chloride prior to MTT with a subsequent back extraction in hexane. This charge-switch derivatization strategy expands lipidome coverage when using MSI-NACE-MS under positive ion mode with improved resolution, greater sensitivity and higher throughput (~ 3.5 min/sample), notably for zwitter-ionic PLs that are analyzed as their cationic phosphate methyl esters. Our method was validated by analyzing methyl-tert-butyl ether extracts of reference human plasma, which allowed for a direct comparison of 48 phosphatidylcholine and 27 sphingomyelin species previously reported in an inter-laboratory lipidomics harmonization study. The potential for plasma PL quantification by MSI-NACE-MS via a serial dilution of NIST SRM-1950 was also demonstrated based on estimation of relative response factors using their reported consensus concentrations from a lipidomics harmonization study. Also, lipid identification was supported by modeling characteristic changes in the electrophoretic mobility for cationic PLs in conjunction with MS/MS. Overall, this work offers a practical derivatization protocol to expand lipidome coverage in CE-MS beyond the analysis of hydrophilic/polar metabolites under aqueous buffer conditions, which may also prove useful in shotgun and LC-MS lipidomic applications.No publisher2024/01/11 07:39:37 GMT-5Article ReferenceHappy Holidays!
https://britz.mcmaster.ca/news/happy-holidays
No publisher2023/12/25 08:00:00 GMT-5News ItemLACE 2023 and visiting our Mexican collegues
https://britz.mcmaster.ca/news/lace-2023-and-visiting-our-mexican-collegues
No publisher2023/12/22 09:32:38 GMT-5News ItemDepartment Christmas Party
https://britz.mcmaster.ca/news/department-christmas-party
No publisher2023/12/18 08:08:06 GMT-5News ItemExpanding Lipidomic Coverage
https://britz.mcmaster.ca/news/expanding-lipidomic-coverage
No publisher2023/11/22 14:15:34 GMT-5News ItemEsther Jin
https://britz.mcmaster.ca/people/esther-jin
No publisherPersonHaley Pandya
https://britz.mcmaster.ca/people/haley-pandya
No publisherPersonYasmin El Moustaine
https://britz.mcmaster.ca/people/yasmin-el-moustaine
No publisherPersonUrinary Metabolite Profiling to Non-Invasively Monitor the Omega-3 Index: An Exploratory Secondary Analysis of a Randomized Clinical Trial in Young Adults
https://britz.mcmaster.ca/publications/articlereference.2023-10-13.8912448426
The Omega-3 Index (O3I) reflects eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) content in erythrocytes. While the O3I is associated with numerous health outcomes, its widespread use is limited. We investigated whether urinary metabolites could be used to non-invasively monitor the O3I in an exploratory analysis of a previous placebo-controlled, parallel arm randomized clinical trial in males and females (n = 88) who consumed either ~3 g/d olive oil (OO; control), EPA, or DHA for 12 weeks. Fasted blood and first-void urine samples were collected at baseline and following supplementation, and they were analyzed via gas chromatography and multisegment injection–capillary electrophoresis–mass spectrometry (MSI-CE-MS), respectively. We tentatively identified S-carboxypropylcysteamine (CPCA) as a novel urinary biomarker reflecting O3I status, which increased following both EPA and DHA (p < 0.001), but not OO supplementation, and was positively correlated to the O3I (R = 0.30, p < 0.001). Additionally, an unknown dianion increased following DHA supplementation, but not EPA or OO. In ROC curve analyses, CPCA outperformed all other urinary metabolites in distinguishing both between OO and EPA or DHA supplementation groups (AUC > 80.0%), whereas the unknown dianion performed best in discriminating OO from DHA alone (AUC = 93.6%). Candidate urinary biomarkers of the O3I were identified that lay the foundation for a non-invasive assessment of omega-3 status.No publisher2023/10/13 09:02:14 GMT-4Article ReferencePublication in collaboration with David Mutch
https://britz.mcmaster.ca/news/publication-in-collaboration-with-david-mutch
No publisher2023/10/13 08:54:45 GMT-4News Item