Abstract WMP109: Distinct Variations in Metabolites, Neurotransmitters, and pH Between Two Stroke Models Suggested by Chemical Exchange Saturation Transfer (CEST) MRI

• DOI: 10.1161/str.56.suppl_1.wmp109
• Publication Date: 2025-01-30T10:33:28Z
• Authors: Kexin Wang; Licheng Ju; Guanda Qiao; Yajie Liang; Yihan Wu; Chengyan Chu; Joshua Rogers; Yuguo Li; Suyi Cao; Valina Dawson; Ted Dawson; Piotr Walczak; Jiadi Xu
• Keywords: Stroke

Introduction: During acute ischemic stroke, energy depletion leads to a rise in creatine (Cr) as buffer, increased extracellular glutamate from impaired neurotransmitter transport, and pH drop due lactic acid buildup. Understanding these changes is crucial for timely intervention, yet no current method captures all alterations simultaneously. CEST, novel MRI technique, non-invasively maps metabolites with high sensitivity, providing information on both concentration pH. Our group recently demonstrated guanidino CEST (GuanCEST) at 3T, reflecting Cr levels, while amine (amineCEST) 9.4T likely indicates glutamate, amide (amideCEST) correlates We aim use techniques investigate metabolic, neurotransmitter, two mouse models of middle cerebral artery occlusion (MCAO). Methods: Ten male C57BL/6 mice (aged 3–6 months) were used stroke models: permanent MCAO (pMCAO, n=4) transient (tMCAO, n=4). scans conducted 3T. Diffusion-weighted imaging identified lesions, followed by T 1 2 mapping the selected slice. performed 2s saturation time across B values ranging 0.4 3.0 μT. utilized Polynomial Lorentzian Line-shape Fitting (PLOF) simultaneously extract GuanCEST, amineCEST, amideCEST spectrum each pixel, generating corresponding maps. The average lesion contralateral hemisphere analyzed. Results: At μT, GuanCEST (Fig. 1, red line) 1.01±0.19% pMCAO compared but decreased 0.32±0.27% tMCAO, indicating greater pMCAO. higher , effects diminished increased. When exceeded 0.8 amineCEST 3.86±0.42% nearly four times (1.09±0.26%), possibly cell membrane polarization depletion. 1.6 0.53±0.05% remained stable tMCAO (0.49±0.48%), suggesting tissue acidification Similar trends observed except was undetectable. Conclusion: non-invasive technique capable metabolite, stroke-affected brain, strong potential clinical translation.