Limited impacts of dietary Protandim Nrf2 Synergizer on antioxidant and inflammatory status of mature, sedentary horses.
Abstract: Reactive oxygen species are normal by-products of cellular metabolism but may have detrimental effects on cellular matrices and excite inflammatory pathways when overproduced. To test the hypothesis that supplementation of an herbal extract combination would: 1) improve antioxidant status; 2) increase anti-inflammatory cytokines; and 3) decrease pro-inflammatory cytokines, 40 mature, sedentary stock-type horses (32 mares, 8 geldings, mean±SD; 15.7 ± 4.9 yr, 519 ± 46 kg) were stratified by age, sex, and body weight and randomly assigned to one of four dietary treatment groups for 56 d: 1) 0 mg (CON); 2) 675 mg (Pro1); 3) 2,025 mg (Pro3); or 4) 4,050 mg (Pro6) Protandim Nrf2 Synergizer (LifeVantage Corporation) per day (n = 10/group). Horses were group housed and received a basal diet of mixed warm-season grass pasture and hay ad libitum and a custom-formulated concentrate grain. Blood collected prior to the morning feeding on day 0, 28, and 56 was analyzed for hydrogen peroxide (H2O2) production and concentration, superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activities, concentrations of malondialdehyde (MDA), cytokines [interleukin (IL)-4, IL -6, IL -8, IL -10 and tumor necrosis factor α], and caffeine, and mRNA expression of IL -1β, Nrf2, and HMOX1. Activities of GPx and SOD were also quantified in gluteus medius samples collected at day 0 and 56. Data were analyzed using linear models in SAS v9.4; sex, time, treatment, and time×treatment were fixed effects and time was a repeated effect with horse(treatment) as the subject. Plasma caffeine concentrations increased from day 0 to 56 in supplemented horses (P ≤ 0.05) in a dose-dependent fashion but did not change in CON horses, resulting in Pro6 horses having the greatest concentration of caffeine at day 56, followed by Pro3, Pro1, then CON horses. No other measure was impacted by treatment though whole blood H2O2 production, SOD activity, and IL -1β mRNA, and plasma IL -8 and MDA concentrations decreased by day 28 (P ≤0.006), whole blood Nrf2 mRNA and IL -10 concentrations decreased by day 56 (P≤0.04), and skeletal muscle GPx activity increased by day 56 (P = 0.05) in all horses. Dietary supplementation of up to 4,050 mg/d Protandim Nrf2 Synergizer did not impact antioxidant status or plasma cytokines in mature, sedentary horses. Effects of supplementation on these variables should be investigated in horses subjected to elevated oxidative and/or inflammatory insult, such as during exercise or aging. Reactive oxygen species (ROS) are byproducts of energy production that have the potential to detrimentally interact with cellular components, creating damage or dysfunction within the body. In small quantities, ROS are important signaling molecules, essential for stimulating adaptation to stimuli such as inflammation and exercise. However, when ROS production exceeds that of antioxidants, neutralizing agents of ROS, negative consequences such as inflammation may result. To combat this, antioxidants are prophylactically supplemented in various forms with herbal formulated blends becoming a growing field of interest. To evaluate the antioxidant and anti-inflammatory potential of Protandim Nrf2 Synergizer, an herbal blend containing milk thistle, bacopa, ashwagandha, green tea, and turmeric, four concentrations were provided to mature, sedentary horses for 56 d. Blood caffeine concentrations increased in a dose-dependent manner but remained below the acceptable concentration for competition horses within the United States, allowing its potential use in equine athletes. No other differences were observed at the Protandim concentrations tested but further research evaluating an increased dosage or to horses experiencing elevated stress is warranted.
© The Author(s) 2025. Published by Oxford University Press on behalf of the American Society of Animal Science.
Publication Date: 2025-12-16 PubMed ID: 41397914PubMed Central: PMC12918311DOI: 10.1093/jas/skaf433Google Scholar: Lookup
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Summary
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Research Overview
- This study evaluated the effects of a herbal supplement, Protandim Nrf2 Synergizer, on antioxidant and inflammatory markers in mature, sedentary horses over 56 days.
- The researchers found no significant impact of the supplement on antioxidant enzymes or inflammatory cytokines, though caffeine levels increased in supplemented horses.
- They suggest that future studies should investigate the supplement’s effects in horses under stress conditions like exercise or aging.
Background and Hypothesis
- Reactive oxygen species (ROS) are natural by-products of cellular metabolism that can cause cellular damage and inflammation if overproduced.
- Antioxidants neutralize ROS to prevent potential harm, and supplementation with herbal antioxidant blends is gaining interest as a preventive strategy.
- Protandim Nrf2 Synergizer is a herbal combination containing milk thistle, bacopa, ashwagandha, green tea, and turmeric, proposed to boost antioxidant defenses and modulate inflammation.
- The study tested whether supplementation would:
- Improve antioxidant status (increase enzymes like SOD, GPx, and CAT)
- Increase anti-inflammatory cytokines
- Decrease pro-inflammatory cytokines
Experimental Design
- Subjects: 40 mature, sedentary stock-type horses (32 mares, 8 geldings), mean age ~15.7 years, mean weight ~519 kg.
- Group Allocation: Horses stratified by age, sex, weight and randomized into 4 groups (n=10 per group):
- Control (CON): 0 mg Protandim
- Pro1: 675 mg/day Protandim
- Pro3: 2,025 mg/day Protandim
- Pro6: 4,050 mg/day Protandim
- Housing and Diet: Group housed with pasture and hay ad libitum plus custom concentrate grain.
- Duration: 56 days supplementation.
- Sample Collection: Blood sampled at baseline (day 0), day 28, and day 56; skeletal muscle biopsies at day 0 and day 56.
Measurements
- Antioxidant markers measured in blood and muscle:
- Hydrogen peroxide (H2O2) production and concentration
- Activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT)
- Malondialdehyde (MDA), a lipid peroxidation marker
- Inflammatory markers and cytokines in plasma and mRNA expression:
- Cytokines: IL-1β, IL-4, IL-6, IL-8, IL-10, tumor necrosis factor α (TNF-α)
- mRNA expression of IL-1β, Nrf2 (a key antioxidant transcription factor), and HMOX1 (heme oxygenase 1)
- Plasma caffeine concentration as a marker of supplement intake.
Key Results
- Plasma caffeine concentrations:
- Increased in a dose-dependent fashion with Protandim supplementation.
- Pro6 group (highest dose) had the greatest increase at day 56, confirming supplement consumption.
- Levels remained below thresholds set for competition horses in the United States, indicating potential future use.
- No significant effect of Protandim treatment on:
- Antioxidant enzyme activities (SOD, GPx, CAT)
- ROS levels (H2O2, MDA)
- Inflammatory cytokines (IL-4, IL-6, IL-8, IL-10, TNF-α) or mRNA expression of IL-1β, Nrf2, HMOX1
- Time effects observed across all horses (regardless of treatment):
- Decreases in H2O2 production, SOD activity, IL-1β mRNA, plasma IL-8 and MDA by day 28
- Decrease in Nrf2 mRNA and plasma IL-10 by day 56
- Increase in skeletal muscle GPx activity by day 56
Interpretation and Conclusions
- Supplementing Protandim up to 4,050 mg/day in mature, sedentary horses did not improve antioxidant status or change inflammatory markers under normal conditions.
- The confirmed increase in plasma caffeine indicates compliance and bioavailability of the supplement.
- Observed time-related changes suggest natural fluctuations in oxidative and inflammatory markers independent of treatment.
- The lack of significant effects might be due to the horses’ sedentary status and lack of oxidative stress or inflammatory challenge.
- Authors recommend future studies to:
- Test higher doses of the supplement
- Assess effects in horses undergoing oxidative or inflammatory stress, such as exercise, aging, or disease states
Significance and Implications
- This study provides foundational data about the safety and limited efficacy of Protandim supplementation in healthy, inactive horses.
- It helps establish a baseline for future research on nutraceutical antioxidant supplements in equine health.
- The increase in caffeine without adverse effects supports potential future use in competitive horses, pending further research.
Cite This Article
APA
Semanchik PL, Wesolowski LT, Artman JL, Seward RL, Beer C, Barnes ED, White-Springer SH.
(2025).
Limited impacts of dietary Protandim Nrf2 Synergizer on antioxidant and inflammatory status of mature, sedentary horses.
J Anim Sci, 104, skaf433.
https://doi.org/10.1093/jas/skaf433 Publication
Researcher Affiliations
- Department of Animal Science, Texas A&M University and Texas A&M AgriLife Research, College Station, TX 77843.
- Department of Animal Science, Texas A&M University and Texas A&M AgriLife Research, College Station, TX 77843.
- Department of Animal Science, Texas A&M University and Texas A&M AgriLife Research, College Station, TX 77843.
- LifeVantage Corporation, Lehi, UT 84043.
- LifeVantage Corporation, Lehi, UT 84043.
- LifeVantage Corporation, Lehi, UT 84043.
- Department of Animal Science, Texas A&M University and Texas A&M AgriLife Research, College Station, TX 77843.
- Department of Kinesiology and Sport Management, Texas A&M University, College Station, TX 77843.
MeSH Terms
- Animals
- Horses / physiology
- Male
- Diet / veterinary
- Female
- Antioxidants / metabolism
- Animal Feed / analysis
- Dietary Supplements / analysis
- NF-E2-Related Factor 2 / metabolism
- Inflammation / veterinary
- Cytokines / metabolism
- Cytokines / genetics
- Plant Extracts / pharmacology
- Plant Extracts / administration & dosage
- Animal Nutritional Physiological Phenomena
Grant Funding
- LifeVantage Corporation
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