Spermidine and spermine are enriched in whole blood of nona/centenarians

Polyamines (putrescine, spermidine, and spermine) are a family of molecules that derive from ornithine through a decarboxylation process. They are essential for cell growth and proliferation, stabilization of negative charges of DNA, RNA transcription, translation, and apoptosis. Recently, it has been demonstrated that exogenously administered spermidine promotes longevity in yeasts, flies, worms, and human cultured immune cells. Here, using a cross-sectional observational study, we determined whole-blood polyamines levels from 78 sex-matched unrelated individuals divided into three age groups: Group 1 (31-56 years, n=26, mean age 44.6±6.07), group 2 (60-80 years, n=26, mean age 68.7±6.07), and group 3 (90-106 years, n=26, mean age 96.5±4.59). The total content of polyamines is significantly lower in groups 2 and 3 compared to group 1 (p=3.6×10(-12)). Interestingly, this reduction is mainly attributable to the lower putrescine content. Group 2 displays the lowest levels of spermidine and spermine. On the other hand, nona/centenarians (group 3) display a significantly higher median relative percentage content of spermine with respect to total polyamines, compared to the other groups (13.2% vs. 14.1% vs. 30.6%, p=6.0×10(-4)). For the first time, we report profiles of polyamines from the whole blood of healthy nona/centenarians, and our results confirm and extend previous findings on the role of polyamines in determining human longevity. However, although we found an important correlation between polyamines levels and age groups, further studies are warranted to fully understand the role of polyamines in determining life span. Also, longitudinal and nutritional studies might suggest potential therapeutic approaches to sustain healthy aging and to increase human life span.