November/December 2025 Vol 31.6Effects of Spermidine-Rich Rice Germ Extract Supplement on Biomarkers of Healthy Aging and Autophagy—Proof-of-Concept Pilot Study
Authors: Gene Bruno DBM, MS, RH(AHG), Michael La Monica PhD, CSCS, Tim N. Ziegenfuss PhD, CSCS, FISSN
Abstract:
Background ??? Although epidemiological and preclinical research suggests that the polyamine spermidine improves the efficiency of autophagy, human clinical research demonstrating a specific dose of any source of spermidine capable of increasing biomarkers of autophagy is lacking.
Primary Study Objective ??? The study aimed to examine the effects of spermidine from Miricell?"? rice germ extract (Nutraland USA) on biomarkers/indices of autophagy, neuroprotection, and cardiometabolic health, as well as safety and adverse events.
Methods/Design ??? This 56-day study was conducted as a single-blinded, interventional, parallel-group, pilot trial. Vitals, diet records, and protocol compliance were recorded at weeks 0 and 8. Blood draws for cardiometabolic markers and adverse event monitoring took place at screening and weeks 0 and 8.
Setting ??? Conducted at a clinical research laboratory in Ohio.
Participants ??? Twelve (N=12) healthy men and women (age: 54.5 ± 7.9 years).
Intervention ??? Random assignment to 1.5 mg or 3.3 mg of spermidine daily from Miricell?"? rice germ extract (Nutraland USA).
Primary Outcome Measures ??? Biomarkers of autophagy [Beclin-1 and Unc-51-like kinase 1(ULK1)], and biomarkers/indices of neuroprotection, including brain-derived neurotrophic factor (BDNF), homocysteine, and cardiometabolic health (high sensitivity C-reactive protein (hs-CRP), lipid panel).
Results ??? Compared to baseline, only the 3.3 mg dose of spermidine from Miricell?"? increased Beclin-1 by 7.3%, ULK-1 by 13.4%, and BDNF by 12.1%. Compared to baseline, the same dose resulted in a 20.8% decrease in hs-CRP, a 20.1% decrease in VLDL, and a 26.9% decrease in triglycerides. Secondary outcomes, including clinical chemistry panel, CBC, vital signs, and adverse events, reflect a good safety profile for the use of 3.3 mg/day of spermidine from Miricell?"?.
Conclusion ??? This pilot study found that 3.3 mg/day of spermidine from Miricell?"? rice germ extract tends to improve biomarkers of autophagy, neuroprotection, and cardiometabolic health. Appropriate follow-up studies are warranted to confirm these findings. (Altern Ther Health Med. [E-pub ahead of print.])
