Clinical biomarker potential of spectrin breakdown degradation products: a systematic review

BACKGROUND: Spectrin is a cytoskeletal protein responsible for the structural integrity of the cell. The protein breaks down to form spectrin breakdown degradation products (SBDPs), which are associated with a range of neurological conditions that warrant further study. This review aims to summarize the clinical potential and scope of SBDPs. METHODOLOGY: Per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA 2020) guidelines, a systematic search up to June 2025 was conducted across databases such as PubMed, Scopus, Embase, and Cochrane Library. Data was extracted on the main study characteristics, and risk of bias assessment done using the Newcastle-Ottawa Scale. RESULTS: From the initial screening of 225 articles, 30 were included in this systematic review. The included studies varied from low-to-moderate risk of bias and demonstrated substantial methodological heterogeneity in study design and populations. Elevated SBDP levels were consistently correlated with injury severity, prognosis, and complications. Positive associations with standard tools such as the Glasgow Coma Scale, Glasgow Outcome Scale, and neuroimaging were observed, although few of the studies had non-significant results. DISCUSSION: This review demonstrates the prognostic and diagnostic potential of SBDPs across several acute neurological conditions. Their role in chronic conditions is limited, and further studies are needed to establish their clinical utility and consistent cut-off values. CONCLUSION: SBDPs, such as SBDP120, 145, and 150, show promise as biomarkers of neuronal injury, although evidence is limited in some clinical conditions, however, their clinical applicability remains context-dependent and is currently limited by methodological heterogeneity. Standardized assays, larger cohorts, and longitudinal studies are needed to strengthen the existing promising evidence.