{"doi":"10.1002/jmri.29598","title":"Z‐Spectral <scp>MRI</scp> Quantifies the Mass and Metabolic Activity of Adipose Tissues With Fat‐Water‐Fraction and Amide‐Proton‐Transfer Contrasts","abstract":"BACKGROUND: Brown adipose tissue (BAT) is metabolically activatable and plays an important role in obesity and metabolic diseases. With reduced fat-water-fraction (FWF) compared with white adipose tissue (WAT), BAT mass and its functional activation may be quantified with Z-spectra MRI, with built-in FWF and the metabolic amide proton transfer (APT) contrasts. PURPOSE: To investigate if Z-spectral MRI can quantify the mass and metabolic activity of adipose tissues. STUDY TYPE: Prospective. SUBJECTS: Seven groups of 8-week-old male rats, including two groups (n = 7 per group) for in vivo MRI study and five groups (n = 5 per group) for ex vivo validation; 12 young and healthy volunteers with 6 male and 6 female. FIELD STRENGTH/SEQUENCE: -weighted imaging, Rapid Acquisition with Relaxation Enhancement (RARE) readout based chemical exchange saturation transfer (CEST) Z-spectral MRI sequence. ASSESSMENT: Quantified FWF and APT from Z-spectra in rats before and after norepinephrine (NE) stimulation and in healthy human subjects; ex vivo measurements of total proteins in BAT from rats. STATISTICAL TESTS: Two-tailed unpaired Student's t-tests and repeated measures ANOVA. P-value <0.05 was considered significant. RESULTS: Decreased FWF (from 39.6% ± 7.2% before NE injection to 16.4% ± 7.2% 120 minutes after NE injection, P < 0.0001) and elevated APT (from 1.1% ± 0.5% before NE injection to 2.9% ± 0.5% 120 minutes after NE injection, P < 0.0001) signals in BAT were observed with in vivo Z-spectral MRI in rats injected with NE at 7 T MRI. At clinical 3 T, Z-spectral MRI was used to quantify the FWF (58.5% ± 7.2% in BAT and 73.7% ± 6.5% in WAT with P < 0.0001) and APT (2.6% ± 0.8% in BAT and 0.9% ± 0.3% in WAT with P < 0.0001) signals in healthy volunteers. APT signals of BAT were negatively correlated with the BMI in humans (r = 0.71). DATA CONCLUSION: Endogenous Z-spectral MRI was demonstrated to simultaneously quantify BAT mass and function based on its FWF and APT contrasts. TECHNICAL EFFICACY STAGE: 1.","journal":"Journal of Magnetic Resonance Imaging","year":2024,"id":481265,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":1,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9528,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2024-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1215967,"name":"Qiaoling Zhong","orcid":"0000-0002-1269-8106","position":1,"is_corresponding":false},{"id":1308254,"name":"Daming Zhang","orcid":"0000-0002-5651-8699","position":2,"is_corresponding":false},{"id":1215968,"name":"Yanqiu Feng","orcid":"0009-0000-5830-4697","position":3,"is_corresponding":false},{"id":1320947,"name":"Qian Wang","orcid":"0000-0003-4755-7001","position":4,"is_corresponding":false},{"id":1308253,"name":"Yuanbo Yang","orcid":"0009-0006-2098-2541","position":5,"is_corresponding":false},{"id":1321348,"name":"Yongzhou Xu","orcid":null,"position":6,"is_corresponding":false},{"id":1216625,"name":"Changhong Liang","orcid":null,"position":7,"is_corresponding":false},{"id":1215969,"name":"Zaiyi Liu","orcid":"0000-0002-9307-8522","position":8,"is_corresponding":false},{"id":416116,"name":"Kejia Cai","orcid":"0000-0003-1511-4273","position":9,"is_corresponding":false},{"id":1308256,"name":"Zimeng Cai","orcid":"0000-0003-0583-5560","position":0,"is_corresponding":true}],"reference_count":48,"raw_metadata":null,"created_at":"2026-07-19T02:07:06.225103Z","pmid":"39215496","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}