Serum proteomics reveals biomarkers for diagnosis, stratification, and mechanistic insights into cerebral microbleeds
Wu-Meng Yin1,2, Liu-Chang He1, Guang-Yi Han1
1Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.
Objective:
Cerebral microbleeds (CMBs) are small vascular lesions detectable on MRI and are associated with increased stroke risk and cognitive decline. However, imaging-based diagnosis is limited by cost and accessibility. This study aimed to identify serum protein biomarkers for early CMB diagnosis and to elucidate molecular mechanisms underlying CMB subtypes.
Methods:
We enrolled 43 patients with MRI confirmed CMBs and 38 healthy controls. Serum proteomic profiling used high performance liquid chromatography coupled with tandem mass spectrometry. Differential protein expression and pathway enrichment analyses were performed. Biomarkers were selected using LASSO, support vector machine recursive feature elimination, and random forest algorithms. Validation employed enzyme linked immunosorbent assay (n = 60) and Western blotting (n = 8).
Results:
We identified 151 proteins that differed between CMB and control groups. Altered pathways involved inflammation, extracellular matrix remodeling, and lipid metabolism. Five proteins emerged as candidate biomarkers: MMP3, EFEMP1, TIMP1, UMOD, and UBA52. MMP3, EFEMP1, TIMP1, and UMOD showed robust validation performance with AUC values > 0.7, and EFEMP1 positively correlated with CMB burden. Subtype analysis distinguished lobar from deep CMBs, with RCN1, NEO1, and APLP1 effectively discriminating subtypes with AUC values > 0.8. Pathway analysis highlighted MAPK, RAF, and ERK signaling in deep CMBs and IGF signaling in lobar CMBs.
Interpretation:
This study presents the first comprehensive serum proteomic landscape of CMBs and identifies novel biomarkers with potential for noninvasive early diagnosis and subtype differentiation, supporting precision medicine approaches for CMB management. IGF and MAPK pathway signatures suggest mechanistic links between CMB subtypes and neurovascular aging.
Insights
Researchers identified novel serum protein biomarkers for early diagnosis of cerebral microbleeds (CMBs). These biomarkers may also help differentiate CMB subtypes, paving the way for personalized treatment strategies.
Area of Science:
- Neuroscience
- Biochemistry
- Proteomics
Background:
- Cerebral microbleeds (CMBs) are small vascular lesions linked to stroke risk and cognitive decline.
- Current MRI-based diagnosis of CMBs faces limitations in cost and accessibility.
- Identifying non-invasive biomarkers is crucial for early detection and management.
Purpose of the Study:
- To discover serum protein biomarkers for early diagnosis of cerebral microbleeds (CMBs).
- To elucidate the molecular mechanisms underlying different CMB subtypes.
- To explore potential for non-invasive CMB diagnosis and subtype differentiation.
Main Methods:
- Serum proteomic profiling using high-performance liquid chromatography and tandem mass spectrometry in 43 CMB patients and 38 controls.
- Differential protein expression analysis and pathway enrichment analysis.
- Biomarker selection using machine learning algorithms (LASSO, SVM-RFE, Random Forest) and validation via ELISA and Western blotting.
Main Results:
- 151 differentially expressed proteins identified between CMB and control groups, implicating inflammation, ECM remodeling, and lipid metabolism pathways.
- Five candidate serum biomarkers (MMP3, EFEMP1, TIMP1, UMOD, UBA52) were identified, with four showing robust validation (AUC > 0.7).
- Specific protein signatures differentiated lobar from deep CMBs (AUC > 0.8), linked to MAPK and IGF signaling pathways.
Conclusions:
- This study provides the first comprehensive serum proteomic analysis of CMBs, identifying novel biomarkers for early, non-invasive diagnosis.
- The identified biomarkers and pathway signatures offer potential for precise CMB subtype differentiation and personalized management.
- Findings suggest mechanistic links between CMB subtypes, neurovascular aging, and specific signaling pathways (MAPK, IGF).
