Difference in acute and chronic stage ischemic stroke metabolic markers with controls

Circulating lipidome underpins gender differences in the pathogenesis of type 2 diabetes

Metabolic alterations in human lipidome significantly impact various chronic diseases including type 2 diabetes (T2D). However, epidemiology and clinical studies have yet to identify clinically meaningful lipid markers for T2D. Fatty acids (FAs) are the backbone of lipid species. However, conflicting results on the essential FAs including omega 3 and omega 6 in the development of metabolic diseases urge deeper evaluations of diverse clinical cohorts including underrepresented populations. This study investigated the lipidomics profiles of 3000 individuals from a well-characterized cohort of Asian Indians. Untargeted lipidomic profiles were created using blood samples applying reversed-phase liquid chromatography-accurate mass tandem mass spectrometry. Free FAs and lysophosphatidylcholines (LPC) were upregulated, while sphingomyelin (SM) and phosphatidylcholines (PC) were decreased in T2D. We observed a significant increase of essential FAs -FA20:4 (AA), FA20:5 (EPA), and FA22:6 (DHA) in T2D after adjusting for age, gender, and BMI. However, most ω-3 and ω-6 FAs were reduced by 2 to 6-fold in obesity in both genders. We also observed gender differences in age-associated lipid patterns in which cholesterol sulfate and LPC 22:6 were elevated in all age groups in men, but LPC 22:6 rapidly increased after menopause in women, and SMs increased in men after 40 years. Machine learning analysis identified long-chain FAs, ether-based LPCs, and clinical risk scores among the most informative features associated with T2D. Our study identified lipidomic markers that could be potential mediators of T2D and obesity. Their patterns may underpin sex differences in the pathogenesis of metabolic and cardiovascular diseases.

Corroborated evidence on change of metabolome after ischemic stroke due to large vessel occlusion

INTRODUCTION

Metabolomic studies which search for acute ischemic stroke (AIS) biomarkers commonly have contradictory findings. Robust methodology is required to understand true metabolome changes after AIS.

METHODS

To improve validity, we obtained corroborative evidence on change of serum metabolome after AIS by: (1) focusing on patients with large vessel occlusion (LVO), (2) combining cross-sectional and longitudinal study designs, and (3) performing analysis using different metabolome platforms: Nuclear Magnetic Resonance (NMR) and Liquid Chromatography-Mass Spectrometry (LC-MS). In the cross-sectional part we compared serum metabolome of 84 AIS patients and 82 controls using NMR at 48-72 h, while in the longitudinal part we prospectively analyzed serum metabolome using LC-MS on 15 AIS patients at < 24 h, 48-72 h, 5-7 days, 80-120 days. We hypothesized that serum metabolites elevated in cross-sectional part would show rising trajectory in longitudinal part, and vice versa.

RESULTS

We found that glycerol, phosphatidylethanolamine (PE), ceramide, phenylalanine and their derivatives had consistent increases, while other key metabolites including histidine, tyrosine, valine, glutamine, phosphatidylcholine (PC), sphingomyelin, fatty acids (FA) had consistent decreases after AIS.

CONCLUSION

We identified corroborated changes in metabolome after AIS across different technologies and study designs. These changes correspond to loss of nerve cell membrane integrity and activation of alternative metabolic pathways in the setting of blood brain barrier (BBB) disruption. If proven on a larger sample, our findings may improve prediction of mortality, and functional outcomes after AIS.

Novel Metabolites as Potential Indicators of Recovery After Large Vessel Occlusion Stroke: A Pilot Study

Introduction: Serum metabolome changes after acute ischemic stroke (AIS), but the significance of this is poorly understood. We evaluated whether this change is associated with AIS outcomes in patients with large vessel occlusion (LVO). To improve validity, we combined cross-sectional and longitudinal designs and analyzed serum using Nuclear Magnetic Resonance (NMR) and Liquid Chromatography-Mass Spectrometry (LC-MS). Methodology: In the cross-sectional part, we compared serum metabolome from 48 LVO strokes, collected at 48-72 h, and analyzed with NMR, while in the longitudinal part, we compared metabolome from 15 LVO strokes, collected at <24 h, 48-72 h, 5-7 days, and 80-120 days, and analyzed with LC-MS between patients with modified Rankin Scores (mRS) of 0-3 and 4-6 at 90 days. We hypothesized that compounds elevated in patients with mRS 0-3 in the cross-sectional part would also be elevated in the longitudinal part, and vice versa. We used regression for the analysis and TSBH for multiple testing. Results: In the cross-sectional part, cholesterol, choline, phosphoglycerides, sphingomyelins, and phosphatidylethanolamines had lower levels in patients with an mRS of 0-3 compared to an mRS of 4-6. In the longitudinal part, lower levels of sphingomyelin (d18:1/19:0, d19:1/18:0)* significantly correlated with an mRS of 0-3 in patients with small infarction volume, while lower levels of sphingolipid N-palmitoyl-sphingosine (d18:1/16:0), 1-palmitoyl-2-docosahexaenoyl-GPC (16:0/22:6), 1-palmitoyl-2-docosahexaenoyl-GPE, palmitoyl-docosahexaenoyl-glycerol (16:0/22:6), campesterol, and 3beta-hydroxy-5-cholestenoate correlated with an mRS of 0-3 in patients with large infarction volume. Conclusions: This pilot study showed that lower levels of lipidomic components nerve cell membrane correlate with good AIS outcomes. If proven on large-scale studies, these compounds may become important AIS outcome markers.

Metabolomic discoveries for early diagnosis and traditional Chinese medicine efficacy in ischemic stroke

Ischemic stroke (IS), a devastating cerebrovascular accident, presents with high mortality and morbidity. Following IS onset, a cascade of pathological changes, including excitotoxicity, inflammatory damage, and blood-brain barrier disruption, significantly impacts prognosis. However, current clinical practices struggle with early diagnosis and identifying these alterations. Metabolomics, a powerful tool in systems biology, offers a promising avenue for uncovering early diagnostic biomarkers for IS. By analyzing dynamic metabolic profiles, metabolomics can not only aid in identifying early IS biomarkers but also evaluate Traditional Chinese Medicine (TCM) efficacy and explore its mechanisms of action in IS treatment. Animal studies demonstrate that TCM interventions modulate specific metabolite levels, potentially reflecting their therapeutic effects. Identifying relevant metabolites in cerebral ischemia patients holds immense potential for early diagnosis and improved outcomes. This review focuses on recent metabolomic discoveries of potential early diagnostic biomarkers for IS. We explore variations in metabolites observed across different ages, genders, disease severity, and stages. Additionally, the review examines how specific TCM extracts influence IS development through metabolic changes, potentially revealing their mechanisms of action. Finally, we emphasize the importance of integrating metabolomics with other omics approaches for a comprehensive understanding of IS pathophysiology and TCM efficacy, paving the way for precision medicine in IS management.

NMR based Serum metabolomics revealed metabolic signatures associated with oxidative stress and mitochondrial damage in brain stroke

Brain stroke (BS, also known as a cerebrovascular accident), represents a serious global health crisis. It has been a leading cause of permanent disability and unfortunately, frequent fatalities due to lack of timely medical intervention. While progress has been made in prevention and management, the complexities and consequences of stroke continue to pose significant challenges, especially, its impact on patient's quality of life and independence. During stroke, there is a substantial decrease in oxygen supply to the brain leading to alteration of cellular metabolic pathways, including those involved in mitochondrial-damage, leading to mitochondrial-dysfunction. The present proof-of-the-concept metabolomics study has been performed to gain insights into the metabolic pathways altered following a brain stroke and discover new potential targets for timely interventions to mitigate the effects of cellular and mitochondrial damage in BS. The serum metabolic profiles of 108 BS-patients were measured using 800 MHz NMR spectroscopy and compared with 60 age and sex matched normal control (NC) subjects. Compared to NC, the serum levels of glutamate, TCA-cycle intermediates (such as citrate, succinate, etc.), and membrane metabolites (betaine, choline, etc.) were found to be decreased BS patients, whereas those of methionine, mannose, mannitol, phenylalanine, urea, creatine and organic acids (such as 3-hydroxybutyrate and acetone) were found to be elevated in BS patients. These metabolic changes hinted towards hypoxia mediated mitochondrial dysfunction in BS-patients. Further, the area under receiver operating characteristic curve (ROC) values for five metabolic features (methionine, mannitol, phenylalanine, mannose and urea) found to be more than 0.9 suggesting their high sensitivity and specificity for differentiating BS from NC subjects.

Discovery and validation of circulating stroke metabolites by NMR-based analyses using patients from the MISS and UK Biobank

BACKGROUND

Stroke is a significant health issue in the United States, and identifying biomarkers for the prevention and functional recovery after an acute stroke remains the highest priority. This study aims to identify circulating metabolite signatures that may be associated with stroke pathophysiology by performing discovery and validation studies.

METHODS

We performed targeted metabolomics profiling of 420 participants of the discovery dataset of Metabolome in an Ischemic Stroke Study (MISS) using high-throughput nuclear magnetic resonance (NMR) spectroscopy. A validation study of significantly altered metabolites was conducted using an independent cohort of 117,988 participants from the UK Biobank, whose metabolomics profiles were generated using the same NMR technology.

RESULTS AND CONCLUSION

Our study identified 16 metabolites to be significantly perturbed during acute stroke. Amino acid phenylalanine was significantly increased, while glutamine and histidine were significantly lowered in stroke. Serum levels of apolipoprotein A-1, HDL particles, small HDL particles, essential fatty acids, and phosphatidylcholine were reduced, while ketone bodies like 3-hydroxybutyrate and acetoacetate were markedly increased in stroke. Based on the robust validation in a large independent UK Biobank dataset, some of these analytes may become clinically meaningful biomarkers to predict or prevent stroke in humans.