About

Wimal Pathmasiri, PhD, is an Assistant Professor at the University of North Carolina at Chapel Hill’s Nutrition Research Institute (NRI). His overarching research goal includes understanding the links between exposures, microbial metabolism, and human health. Dr. Pathmasiri has worked with the Sumner Lab for over 12 years, serving as the director of a technology core for the NIH Common Fund Eastern Regional Comprehensive Metabolomics Resource Core and working as a co-investigator in the North Carolina Human Health Exposure Analysis Resource Untargeted Analysis Laboratory. He develops and applies metabolomics to reveal metabolic pathway perturbations associated with disease states, therapeutic treatments, and environmentally relevant exposures. His research contributions span areas such as cancer, childhood obesity, early-life exposure to antibiotics, environmental exposure, kidney disease, osteoarthritis, rare diseases, and toxicology.

Research topics

• Chemistry
• Bioinformatics
• Biology
• Genetics
• Evolutionary biology
• Internal medicine
• Microbiology
• Chromatography
• Biochemistry
• Medicine
• Computational biology
• Pathology

Selected publications

• Best practices in NMR metabolomics: Current state

  UNC Libraries · 2026-04-23

  articleOpen access
  PublisherDOI

• Securing the Future of NMR Metabolomics Reproducibility: A Call for Standardized Reporting

  Analytical Chemistry · 2025-09-15 · 3 citations

  reviewOpen access

  Metabolomics is a rapidly growing multidisciplinary field with ever increasing demand and usability, which is attracting a surge of new researchers. While their varied skill sets, scientific questions, and approaches enrich the field with fresh perspectives and innovation, individual investigators also bring wide-ranging levels of metabolomics-specific experience and diverse areas of interest. These factors introduce considerable variability and inconsistency in both the methodology and reporting. A recent comparative literature review of nuclear magnetic resonance (NMR) metabolomics from studies published in 2010 and 2020 revealed significant shortcomings in the reporting of experimental details necessary for evaluating both the scientific rigor and the reproducibility of NMR-based metabolomics experiments. Each stage of metabolomics research contains multiple methodological choices and various optimization parameters, all of which can introduce experimental bias and alter the study results. This emphasizes the need for proper reporting to enhance reproducibility, data reusability, and study comparability. To address these concerns, the NMR Special Interest Group within the Metabolomics Association of North America presents reporting recommendations focused on fundamental aspects of NMR metabolomics research identified from the detailed literature review report. These include specifics with respect to study design, sample preparation, data acquisition, data processing and analysis, data accessibility, and comparability to previous studies. Also presented is a complementary list of seminal papers in the field to guide the study design and implementation of NMR metabolomics experiments. This initiative seeks to enhance the long-term impact of NMR metabolomics by supporting high-quality, reproducible, and impactful data collected from well-executed and thoroughly reported studies.

  PublisherDOI

• Defining subgroups of pediatric nephrotic patients with urine proteomics

  Scientific Reports · 2025-07-11

  articleOpen access

  The molecular pathophysiology of nephrotic syndrome remains largely elusive in pediatric patients. While most children with minimal change disease (MCD) show favorable responses to immunosuppressive therapy, those with focal segmental glomerulosclerosis (FSGS) often exhibit poorer treatment responses, with many experiencing either partial remission or no remission of proteinuria. The need for reliable glomerular disease biomarkers to predict treatment response and understand molecular pathways governing responsiveness and resistance is a critical unmet need in pediatric nephrology. In this study, we sought to characterize urine proteomes in children with MCD and FSGS to identify biomarkers distinguishing disease activity and associated molecular pathways. Using quantitative proteomics, urine proteins from children with MCD and FSGS in the CureGN Study were identified and correlated with disease onset and activity. Unbiased cluster analyses of nephrotic urine proteomes demonstrated a cluster with relatively increased immune response and complement proteins, suggesting important distinctions in disease characteristics within the nephrotic subgroups. These analyses yielded patient subpopulations with proteinuria and distinct urine proteome differences associated with 116 proteins exerting cluster separation in the multivariate analyses. These findings highlight the potential of unsupervised clustering to identify disease subgroups and provide insights into the underlying molecular heterogeneity within nephrotic syndrome, paving the way for more tailored therapeutic strategies and improved patient management.

  PublisherOA PDFDOI

• Selective Influence of Hemp Fiber Ingestion on Post-Exercise Gut Permeability: A Metabolomics-Based Analysis

  UNC Libraries · 2025-05-02

  articleOpen access

  Objectives: This study investigated the effects of 2-week ingestion of hemp fiber (high and low doses) versus placebo bars on gut permeability and plasma metabolite shifts during recovery from 2.25 h intensive cycling. Hemp hull powder is a rich source of two bioactive compounds, N-trans-caffeoyl tyramine (NCT) and N-trans-feruloyl tyramine (NFT), with potential gut health benefits. Methods: The study participants included 23 male and female cyclists. A three-arm randomized, placebo-controlled, double-blind, crossover design was used with two 2-week supplementation periods and 2-week washout periods. Supplement bars provided 20, 5, or 0 g/d of hemp hull powder. Participants engaged in an intensive 2.25 h cycling bout at the end of each of the three supplementation periods. Five blood samples were collected before and after supplementation (overnight fasted state), and at 0 h-, 1.5 h-, and 3 h-post-exercise. Five-hour urine samples were collected pre-supplementation and post-2.25 h cycling after ingesting a sugar solution containing 5 g of lactulose, 100 mg of 13C mannitol, and 1.9 g of mannitol in 450 mL of water. An increase in the post-exercise lactulose/13C mannitol ratio (L:13CM) was used as the primary indicator of altered gut permeability. Other outcome measures included muscle damage biomarkers (serum creatine kinase, myoglobin), serum cortisol, complete blood cell counts, and shifts in plasma metabolites using untargeted metabolomics. Results: No trial differences were found for L:13CM, cortisol, blood cell counts, and muscle damage biomarkers. Orthogonal partial least-squares discriminant analysis (OPLSDA) showed distinct trial differences when comparing high- and low-dose hemp fiber compared to placebo supplementation (R2Y = 0.987 and 0.995, respectively). Variable Importance in Projection (VIP) scores identified several relevant metabolites, including 3-hydroxy-4-methoxybenzoic acid (VIP = 1.9), serotonin (VIP = 1.5), 5-hydroxytryptophan (VIP = 1.4), and 4-methoxycinnamic acid (VIP = 1.4). Mummichog analysis showed significant effects of hemp fiber intake on multiple metabolic pathways, including alpha-linolenic acid, porphyrin, sphingolipid, arginine and proline, tryptophan, and primary bile acid metabolism. Conclusions: Hemp fiber intake during a 2-week supplementation period did not have a significant effect on post-exercise gut permeability in cyclists (2.25 h cycling bout) using urine sugar data. On the contrary, untargeted metabolomics showed that the combination of consuming nutrient-rich hemp fiber bars and exercising for 135 min increased levels of beneficial metabolites, including those derived from the gut in healthy cyclists.

  PublisherDOI

• Selective Influence of Hemp Fiber Ingestion on Post-Exercise Gut Permeability: A Metabolomics-Based Analysis

  Preprints.org · 2025-03-24 · 1 citations

  preprintOpen access

  Objectives: This study investigated the effects of 2-weeks ingestion of hemp fiber (high and low doses) versus placebo bars on gut permeability and plasma metabolite shifts during recovery from 2.25 h intensive cycling. Hemp hull powder is a rich source of two bioactive compounds, N-trans-caffeoyl tyramine (NCT) and N-trans-feruloyl tyramine (NFT), with potential gut health benefits. Methods: The study participants included 23 male and female cyclists. A 3-arm randomized, placebo-controlled, double-blind, crossover design was used with two 2-week supplementation periods and 2-week washout periods. Supplement bars provided 20-, 5-, or 0 g/d of hemp hull powder. Participants engaged in an intensive 2.25h cycling bout at the end of each of the three supplementation periods. Five blood samples were collected before and after supplementation (overnight fasted state), and at 0h-, 1.5h-, and 3h-post-exercise. Five-hour urine samples were collected pre-supplementation and post-2.25h cycling after ingesting a sugar solution containing lactulose 5 g, 13C mannitol 100 mg, and mannitol 1.9 g in 450 ml water. An increase in the post-exercise lactulose/13C mannitol ratio (L:13CM) was used as the primary indicator of altered gut permeability. Other outcome measures included muscle damage biomarkers (serum creatine kinase, myoglobin), serum cortisol, complete blood cell counts, and shifts in plasma metabolites using untargeted metabolomics. Results: No trial differences were found for L:13CM, cortisol, blood cell counts, and muscle damage biomarkers. Orthogonal partial least squares discriminant analysis (OPLSDA) analysis showed distinct trial differences when comparing high- and low-dose hemp fiber compared to placebo supplementation (R2Y=0.987 and 0.995, respectively). Variable Importance in Projection (VIP) scores identified several relevant metabolites including 3-hydroxy-4-methoxybenzoic acid (VIP=1.9), serotonin (VIP=1.5), 5-hydroxytryptophan (VIP=1.4), and 4-methoxycinnamic acid (VIP=1.4). Mummichog analysis showed significant effects of hemp fiber intake on multiple metabolic pathways including alpha-linolenic acid, porphyrin, sphingolipid, arginine and proline, tryptophan, and primary bile acid metabolism. Conclusions: Hemp fiber intake during a 2-week supplementation period did not have a significant effect on post-exercise gut permeability in cyclists (2.25 h cycling bout) using urine sugar data. On the contrary, untargeted metabolomics showed that the combination of consuming nutrient-rich hemp fiber bars and exercising for 135 minutes increased levels of beneficial metabolites including those derived from the gut in healthy cyclists.

  PublisherOA PDFDOI

• Effect of endotoxin and alum adjuvant vaccine on peanut allergy

  UNC Libraries · 2025-01-16

  articleOpen accessSenior author
  PublisherDOI

• Multi-omics signature of healthy versus unhealthy lifestyles reveals associations with diseases

  Human Genomics · 2025-08-30 · 4 citations

  articleOpen access

  This multi-omics cross-sectional study investigated differences in metabolomics, proteomics, and epigenomics profiles between two groups of adults matched for age but differing in lifestyle factors such as body composition, diet, and physical activity patterns. Data from prior studies were utilized for a comprehensive integrative analysis. The study included 52 participants in the lifestyle group (LIFE) (28 males, 24 females) and 52 in the control group (CON) (27 males, 25 females). Using multi-omics integration software (OmicsNet and Pathview), 96 significantly (p < 0.05) enriched pathways were identified that differentiated the LIFE and CON groups. Top pathways significantly (p < 2.63 × 10−5) influenced by group status included fatty acid degradation, fatty acid elongation, glutathione metabolism, Parkinson disease, and central carbon metabolism in cancer. This study identified a distinct metabolic signature comprised of metabolites, proteins, and gene methylation sites associated with a healthy lifestyle. These findings provide unique, but complementary, results to previous single-omics analyses using metabolomics and proteomics procedures which showed that the LIFE group exhibited lower plasma bile acid levels, higher levels of beneficial fatty acids, reduced innate immune activation, enhanced lipoprotein metabolism, and increased HDL remodeling. The current multi-omics analysis builds on these previous results by providing a more holistic view of how metabolites, proteins, and methylation sites associated with a healthy lifestyle, providing a larger, more comprehensive list of altered pathways. Additionally, the integrated analysis revealed connections between lifestyle factors and conditions such as cancer and insulin resistance beyond what identified in the single-omics approaches, highlighting the broader metabolic impact of lifestyle on health. Overall, the signatures identified by this multi-omics approach provide a basis for developing more translational biomarkers, such as those that defined the cancer and insulin resistance pathways that can be used to assess one’s state of health and provide guidance on behavior modifications that should be taken to lower disease risk.

  PublisherOA PDFDOI

• Pemmican Supplementation Linked to Beneficial Metabolite Signature in Marines During Cold Weather Operations Training

  Current Developments in Nutrition · 2025-05-01 · 1 citations

  articleOpen access
  PublisherOA PDFDOI

• Selective Influence of Hemp Fiber Ingestion on Post-Exercise Gut Permeability: A Metabolomics-Based Analysis

  Nutrients · 2025-04-19

  articleOpen access

  Objectives: This study investigated the effects of 2-week ingestion of hemp fiber (high and low doses) versus placebo bars on gut permeability and plasma metabolite shifts during recovery from 2.25 h intensive cycling. Hemp hull powder is a rich source of two bioactive compounds, N-trans-caffeoyl tyramine (NCT) and N-trans-feruloyl tyramine (NFT), with potential gut health benefits. Methods: The study participants included 23 male and female cyclists. A three-arm randomized, placebo-controlled, double-blind, crossover design was used with two 2-week supplementation periods and 2-week washout periods. Supplement bars provided 20, 5, or 0 g/d of hemp hull powder. Participants engaged in an intensive 2.25 h cycling bout at the end of each of the three supplementation periods. Five blood samples were collected before and after supplementation (overnight fasted state), and at 0 h-, 1.5 h-, and 3 h-post-exercise. Five-hour urine samples were collected pre-supplementation and post-2.25 h cycling after ingesting a sugar solution containing 5 g of lactulose, 100 mg of 13C mannitol, and 1.9 g of mannitol in 450 mL of water. An increase in the post-exercise lactulose/13C mannitol ratio (L:13CM) was used as the primary indicator of altered gut permeability. Other outcome measures included muscle damage biomarkers (serum creatine kinase, myoglobin), serum cortisol, complete blood cell counts, and shifts in plasma metabolites using untargeted metabolomics. Results: No trial differences were found for L:13CM, cortisol, blood cell counts, and muscle damage biomarkers. Orthogonal partial least-squares discriminant analysis (OPLSDA) showed distinct trial differences when comparing high- and low-dose hemp fiber compared to placebo supplementation (R2Y = 0.987 and 0.995, respectively). Variable Importance in Projection (VIP) scores identified several relevant metabolites, including 3-hydroxy-4-methoxybenzoic acid (VIP = 1.9), serotonin (VIP = 1.5), 5-hydroxytryptophan (VIP = 1.4), and 4-methoxycinnamic acid (VIP = 1.4). Mummichog analysis showed significant effects of hemp fiber intake on multiple metabolic pathways, including alpha-linolenic acid, porphyrin, sphingolipid, arginine and proline, tryptophan, and primary bile acid metabolism. Conclusions: Hemp fiber intake during a 2-week supplementation period did not have a significant effect on post-exercise gut permeability in cyclists (2.25 h cycling bout) using urine sugar data. On the contrary, untargeted metabolomics showed that the combination of consuming nutrient-rich hemp fiber bars and exercising for 135 min increased levels of beneficial metabolites, including those derived from the gut in healthy cyclists.

  PublisherOA PDFDOI

• Association of metabolomics measurements with blood cell phenotypes

  Blood Cells Molecules and Diseases · 2025-11-05

  articleOpen access
  PublisherOA PDFDOI

Frequent coauthors

• Susan Sumner

  University of California, Los Angeles

  136 shared

• Susan McRitchie

  98 shared

• Blake R. Rushing

  University of North Carolina at Chapel Hill

  35 shared

• Delisha A. Stewart

  28 shared

• Jon B. Klein

  University of Louisville

  20 shared

• David C. Nieman

  Appalachian State University

  20 shared

• Camila A. Sakaguchi

  Appalachian State University

  20 shared

• Mansi Choudhari

  David H. Murdock Research Institute

  18 shared

Education

• Ph.D., Biochemistry

  Uppsala Universitet

  2007