Single-Cell Metabolomic of Hypertensive Rats Heart Based on Organic Mass Cytometry

Hypertension is a common chronic cardiovascular disease and one of the major risk factors for cardiovascular mortality and disability, with a global prevalence of approximately 15%. This high incidence not only leads to a substantial disease burden but also gives rise to long-term complications that affect the quality of life of millions worldwide. Surveys indicate that the prevalence of hypertension in China is 27.5% and exhibits an annual upward trend, a situation that poses significant challenges to socioeconomic development including increased healthcare costs and reduced workforce productivity, and imposes immense pressure on public health systems. Due to the high heterogeneity among different individual cells, where even cells of the same type can exhibit distinct functional and molecular profiles, and the involvement of multiple cell types in the synergistic regulation of hypertension pathogenesis, it is crucial to explore the regulatory mechanisms of hypertension at the single-cell level. Single-cell metabolomics, a cutting-edge analytical approach, reveals the metabolic characteristics of individual cells by systematically analyzing endogenous small molecules (metabolites) within cells. By capturing the unique metabolic fingerprints of each cell, single-cell metabolomics can directly reflect metabolic disturbances under pathological conditions, offering valuable insights into the early and subtle changes that precede overt disease manifestations. Hypertension-induced myocardial metabolic dysregulation represents a critical pathological basis for cardiovascular diseases, yet its single-cell metabolic signatures remain incompletely characterized. This study established a novel single-cell metabolomics approach for hypertensive hearts using organic mass cytometry (CyESI-MS), aiming to clarify the metabolic regulatory mechanism from a single-cell perspective. Through optimized tissue dissociation protocols, high-viability single-cell suspensions were prepared from spontaneously hypertensive rats (SHR) and normotensive controls, followed by metabolomics analysis via CyESI-MS. As a result, 70 endogenous metabolites are identified at the single-cell level, with 34 demonstrating significant alterations (|log₂FC|≥1, p<0.05). Pathway enrichment analysis reveals five core dysregulated metabolic pathways, including glycerophospholipid metabolism, biosynthesis of phenylalanine, tyrosine and tryptophan, phenylalanine metabolism, histidine metabolism, and taurine and hypotaurine metabolism. This study employed a single-cell metabolomics approach based on mass spectrometry to delve into metabolic changes in rat heart cells under hypertensive conditions, a phenomenon that is often overlooked in large-scale metabolomics studies based on bulk cells or tissue/organ samples. Furthermore, from the perspective of single-cell metabolomics, this research uncovers the metabolic characteristics of individual heart cells under hypertension, thereby providing important reference value for the early diagnosis of hypertension cardiovascular diseases. This study provides the first single-cell evidence of characteristic metabolic reprogramming in hypertensive hearts, offering new insights into cardiovascular disease mechanisms.