Quantitative proteomics analysis to identify diffuse axonal injury biomarkers in rats using iTRAQ coupled LC-MS/MS

Area of Science:

• Neuroscience
• Biochemistry
• Proteomics

Background:

• Diffuse axonal injury (DAI) is a frequent and severe consequence of traumatic brain injury (TBI), often leading to high mortality rates.
• Current clinical practice faces challenges in early DAI diagnosis, treatment decisions, and prognosis due to undefined injury mechanisms and lack of reliable biomarkers.

Purpose of the Study:

• To identify novel protein biomarkers for early diagnosis of DAI.
• To investigate the pathophysiological mechanisms underlying DAI.
• To evaluate the utility of iTRAQ-based quantitative proteomics in cerebral tissue research.

Main Methods:

• An established animal model of DAI was used.
• Isobaric tag for relative and absolute quantification (iTRAQ) coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was employed for protein identification and quantification.
• Western blot and immunohistochemistry were used for validation of candidate biomarkers.

Main Results:

• A total of 1858 proteins were identified and quantified in rat cerebral tissue.
• Ten candidate proteins were identified as differentially expressed, with four (citrate synthase, synaptosomal-associated protein 25, microtubule-associated protein 1B, and Rho-associated protein kinase 2) validated as potential DAI biomarkers.
• The study demonstrated the feasibility of iTRAQ proteomics for analyzing cerebral tissue.

Conclusions:

• Novel protein biomarkers for DAI were identified, offering potential for improved early diagnosis.
• The findings provide insights into the molecular mechanisms of DAI.
• iTRAQ-based quantitative proteomics is a viable approach for DAI research.