Ethanol-induced metabolomic differences in mice using HRAM Q-TOF analysis

Significance of the Topic

The impact of ethanol on brain metabolism is critical for understanding neuropsychiatric disorders and alcohol related neuropathology in preclinical models

Study Objectives and Overview

The aim of this study was to apply untargeted high resolution accurate mass Q-TOF analysis to compare mouse brain metabolite profiles after acute and chronic ethanol exposure

Methodology and Instrumentation

Mouse groups received ethanol for 11 days (acute) or 8 weeks (chronic) alongside untreated controls
Forty two brain tissue samples were randomized and analyzed with pooled and group specific quality control injections
Data were acquired on a Shimadzu LCMS-9030 Q-TOF using simultaneous MS and data independent MS/MS acquisition at 50 Hz with a 0.9 second cycle time
Mass range 50 to 1000 Da was covered with 44 sequential MS/MS scans per cycle
Compound detection was performed in Insight Explore software using the Find algorithm and putative identification against the METLIN database

Results and Discussion

After QC filtering 627 components were included in statistical evaluation

• Acute ethanol exposure induced significant downregulation of 17 endogenous metabolites including adenine, adenosine, arachidonic acid, docosahexaenoic acid, glycerophosphocholine, taurine, creatine, phosphatidylcholine and lysophosphatidylcholine species
• This pattern is consistent with enhanced purine catabolism, reduced phospholipid turnover and neuroinflammatory responses reported in prior studies
• Chronic ethanol exposure produced a mixed response with 15 metabolites elevated and 11 metabolites decreased relative to controls
• Elevated amino acids such as phenylalanine, leucine, proline and tyramine suggest altered neurotransmitter and protein metabolism under sustained ethanol intake
• Depletion of glucosylceramides and certain ceramides reflects ethanol induced membrane lipid perturbation
• The observed rise in docosahexaenoic acid after chronic exposure may indicate compensatory brain uptake to replace depleted pools

Benefits and Practical Applications

This untargeted workflow enables rapid discrimination between acute and chronic ethanol effects in brain tissue
High throughput sample analysis with robust QC integration supports large scale preclinical studies
Identification of metabolite signatures provides candidate biomarkers for alcohol related neurotoxicity

Future Trends and Opportunities

Integration of untargeted metabolomics with targeted validation panels will refine biomarker discovery
Combining metabolic profiles with proteomic and transcriptomic data will advance mechanistic insights
Time course studies and machine learning approaches may reveal dynamic metabolic transitions under ethanol exposure
Translation of these findings to clinical research may support early detection of alcohol related brain injury

Conclusion

An HRAM Q-TOF based untargeted metabolomics method was demonstrated to distinguish acute from chronic ethanol induced brain metabolic changes in mice
Distinct profiles of amino acids, phospholipids and lipid mediators highlight the potential of this approach for preclinical neurotoxicology research

Instrumentation

• Shimadzu LCMS-9030 high resolution accurate mass Q-TOF
• Data independent acquisition with simultaneous MS and MS/MS in a single cycle
• Cycle time of 0.9 seconds covering 50 to 1000 Da mass range with 44 MS/MS events per cycle