Effects of Aleurone Supplementation on Glucose-Insulin Metabolism and Gut Microbiome in Untrained Healthy Horses.
Authors: Boshuizen Berit, Moreno de Vega Carmen Vidal, De Maré Lorie, de Meeûs Constance, de Oliveira Jean Eduardo, Hosotani Guilherme, Gansemans Yannick, Deforce Dieter, Van Nieuwerburgh Filip, Delesalle Catherine
Journal: Frontiers in veterinary science
Summary
# Editorial Summary: Aleurone Supplementation in Horses Aleurone, the nutrient-dense outer layer of cereal bran, has demonstrated metabolic benefits across multiple species, yet its effects in equine nutrition remained unexplored until this 2021 investigation. Seven untrained Standardbred horses received escalating aleurone doses (50–400 g/day) in a controlled crossover design, with postprandial glucose-insulin responses and faecal microbiota characterised via 16S rRNA sequencing and predictive metabolomic analysis. Supplementation induced clinically meaningful dose-dependent improvements: the glucose peak occurred significantly later with higher doses (p = 0.030), insulin peak was delayed (p = 0.025) and suppressed (p = 0.049), and overall insulin exposure decreased markedly (p = 0.019), with 200 g/day emerging as the threshold dose. Whilst microbial diversity remained stable, aleurone substantially shifted community composition—notably reducing fibre-fermenting taxa (Roseburia, Anaerostipes) whilst elevating Bacteroidetes—and modulated metabolic pathways involved in membrane synthesis, suggesting a synergistic interaction between the physical properties of aleurone and its bioactive components. For practitioners managing metabolic disease, insulin dysregulation, or laminitis risk, these findings warrant consideration of aleurone supplementation as a simple dietary intervention to flatten postprandial glucose-insulin curves, though further research in larger populations and clinical cases is needed to establish optimal protocols and long-term efficacy.
Read the full abstract on PubMed
Practical Takeaways
- •Aleurone supplementation at 200+ g/day may help manage postprandial glucose spikes and insulin response in horses, potentially beneficial for metabolic conditions like EMS or PSSM
- •The prebiotic effects on microbiome composition suggest improved digestive function, though clinical benefits require confirmation in larger studies
- •Aleurone appears to work through both feed texture effects and direct bioactive components—consider as part of whole-grain feeding strategies rather than isolated supplement
Key Findings
- •Aleurone supplementation at 200-400 g/day produced dose-dependent delays in postprandial glucose peak (p=0.030) and insulin peak (p=0.025) with reduced insulin peak levels (p=0.049)
- •Aleurone decreased insulin area under the curve (p=0.019), indicating improved glucose-insulin control
- •Aleurone altered gut microbiome composition, decreasing Roseburia, Shuttleworthia, and Anaerostipes while upregulating Bacteroidetes and Spirochaetes phyla
- •Functional microbiome analysis showed aleurone downregulated L-glutamate and taurine degradation pathways and upregulated phospholipid membrane synthesis in Archaea