Elevated spermidine serum levels in mild cognitive impairment, a potential biomarker of progression to Alzheimer dementia, a pilot study

• Published in: Journal of clinical neuroscience Vol. 100; pp. 169 - 174
• Main Authors: Sternberg, Zohara, Podolsky, Rebecca, Nir, Adam, Yu, Jihnhee, Nir, Raphael, Halvorsen, Stanley W, Quinn, Joseph F., Kaye, Jeffrey, Kolb, Channa
• Format: Journal Article
• Language: English
• Published: Scotland Elsevier Ltd 01.06.2022
• Subjects: Alzheimer Disease - diagnostic imaging; Biomarkers; Cognitive Dysfunction - psychology; Cross-Sectional Studies; Disease Progression; Hepcidins; Humans; Iron; Iron homeostasis; Ornithine decarboxylase; Pilot Projects; Polyamine; Serum biomarker; Spermidine; Iron homeostasis; Polyamine; Ornithine decarboxylase; Serum biomarker
• ISSN: 0967-5868; 1532-2653; 1532-2653
• DOI: 10.1016/j.jocn.2022.04.028

•We compared serum levels of the polyamine spermidine between MCI, AD and control subjects.•Serum levels of MCI was significantly higher in MCI subjects.•Spermidine serum levels correlated with AD disease severity (MMSE, CDR and CDR-SOB).•Role of Spemidine and polyamines in AD pathophysiology warrants further investigations. There is a close link between iron and polyamine biosynthesis and metabolism. In a recent study, we reported alterations in the serum levels of hepcidin and other iron-related proteins in Alzheimer’s disease (AD) patients (Sternberg et al., 2017). Based on these findings, this pilot study compared serum levels of one of the polyamines, Spermidine, between AD, mild cognitive impairment (MCI), and control subjects, correlating the levels with the existing clinical and neuroimaging data. This cross-sectional study measured Spermidine levels in frozen serum samples of 43 AD patients, 12 MCI patients, and 21 age-matched controls, provided by the Oregon Alzheimer's Disease Center Bio-repository, using enzyme-linked immunosorbent assay. MCI patients showed significantly higher mean Spermidine serum levels compared to controls (P = 0.01), with a non-significant trend for higher Spermidine serum levels in pure AD (P = 0.08) participants compared to controls. Spermidine serum levels correlated with the values of cognitive assessment tests including MMSE (r = -0.705, P = 0.003), CDR (r = 0.751, P = 0.002), and CDR-SOB (r = 0.704, P = 0.007), in “pure” AD subgroup, suggesting that higher Spermidine serum levels in MCI can be a potential biomarker of conversion to dementia in subjects with AD underlying pathology. Furthermore, Spermidine serum levels correlated with serum levels of the chief iron regulatory protein, hepcidin in AD participants with a more advanced disease stage, indicated by MMSE (strata of 8–19, P = 0.02), and CDR-SOB (strata of 6–12, P = 0.03). Studies with larger cohort are warranted for defining the role of Spermidine in AD pathophysiology, and the utility of polyamines as biomarkers of progression of MCI to AD.