Metabolic Responses to Spermidine Supplementation.

Spermidine is naturally present in cells, organs, circulating cardiovascular system, and as part of our normal dietary intake. Studies suggest Spermidine is involved in antioxidation, autophagy, apoptosis, and immune regulation. Spermidine is typically present in foods of plant origin, such as natto, beans, fruits, vegetables, cheese, potatoes, bread, and cereals. Adequate spermidine dietary intake is important, given evidence of declining spermidine levels with age in humans and other species, and the evidence for positive effects of spermidine supplementation on age related biology.

To date, human research studies utilised extracts containing low levels of spermidine (\< 10%) and multiple other constituents, but this study will use pure spermidine to explore relevant mechanisms of action, biological effects, and identify potential biomarkers of positive biological effects.

This is a placebo controlled, double blind, randomised, within subject controlled study of supplementation with oral spermidine or placebo each for up to four weeks. The primary objective of this exploratory study is to examine the safety and biological effects of this pure full-dose spermidine supplement on metabolomics, inflammatory and metabolic markers, and transcriptomics.

Study subjects are generally healthy males aged 50-70 After screening, subjects will enter a two week run-in (stabilisation) phase and then be randomised to blinded active or placebo for the first one week supplementation period. After a washout period, subjects will receive either blinded placebo or active for a second supplementation period of up to four weeks. The full study will require six visits by each study subject to the study site over a period of nine weeks, for blood and urine samples, and dietary intake assessments.

Subjects are required to maintain a normal consistent dietary intake during the study and abstain from alcohol in the 24 hours before study visits.

Assays include routine haematology and chemistry, CRP (C reactive protein), lipid screen, serum and urine metabolomics and polyamines, lipidomics, transcriptomics, and autophagy assays.

Eligibility Criteria:
Inclusion Criteria:

Caucasian men, 50-70 years of age

Non-user or former users (cessation ≥6 months) of nicotine products (e.g., cigarettes, chewing tobacco) during the study period.

Non-user or former users (cessation ≥6 months) of any marijuana or hemp products and no plans to use marijuana or hemp products during the study period

Willing to maintain physical activity and exercise patterns, body weight, and habitual diet throughout the trial.

No health conditions that would prevent the subject from fulfilling the study requirements as judged by the Clinical Investigator on the basis of medical history, physical examination, and routine laboratory test results.

Understands the study procedures and signs forms providing informed consent to participate in the study and authorizes the release of relevant protected health information to the Clinical Investigator.

Exclusion Criteria:

Abnormal laboratory test results of clinical significance

Clinically important gastrointestinal (GI) condition that would potentially interfere with the evaluation of the study product

Type I or Type II diabetes mellitus.

Uncontrolled pulmonary (including uncontrolled asthma), cardiac, hepatic, renal, endocrine, hematologic, immunologic, or neurologic disease.

Had a positive SARS-CoV2 (COVID) test and experienced symptoms for \> 2 months (i.e. long COVID)

Has a condition the Clinical Investigator believes would interfere with ability to provide informed consent, comply with the study protocol, which might confound the interpretation of the study results, or put the subject at undue risk