15 Unique yeast-derived prebiotic supports joint health and reduced systemic inflammation in senior horses

Abstract

Senior horses are commonly afflicted with inflammation-related conditions including chronic or acute joint inflammation, and chronic low-grade systemic inflammation, or “inflamm-aging.” Reducing inflammation, where appropriate, may improve the quality of life and performance of senior horses. To that end, the objective of this trial was to determine whether supplementation of a unique yeast-derived prebiotic (ActivAge®(AA)) to senior horses would promote reduced joint and systemic inflammation. Aged Quarter horses (n = 10; mean age ± SEM = 21.3 ± 1.2yr; mean BW ± SEM = 587.5 ± 10.9kg; mean BCS ± SEM = 6.3 ± 0.2) were utilized in a crossover trial. Horses were randomly assigned to either a control (CON) or treatment (TRT) group. Horses in both groups were offered 4.54 kg/d Purina® Equine Senior® (CP = 14.5%, Ca = 0.76%, P = 0.61%). Horses were offered 1.25% BW as local grass hay (CP = 14.6%, Ca = 0.60%, P = 0.30%) daily. Horses were additionally offered 0.45 kg/d of a pellet containing AA (TRT) or not (CON). Daily ration was split into 2 equal feedings at 0700 and 1300 daily for 42d per period with a 28d washout period during which no TRT or CON pellet was offered. All horses had ad libitum access to fresh clean water and white salt. Serum samples were obtained via jugular venipuncture approximately 2hr post feeding every 2wk foranalysis of the acute phase protein, serum amyloid A (SAA; SAA-Vet, Eiken Chemical Co.). On d42 horses underwent a joint inflammation challenge. Briefly, 1mL of a sterile saline solution containing 0.5ng lipopolysaccharide from E. coli 055:B5 (Sigma-Aldrich) was injected into the radiocarpal joint. The contralateral joint was used as a control with only sterile saline injected. Synovial fluid was collected aseptically immediately before injection and at 5, 24, and 48hr post injection. All data were analyzed via ANOVA utilizing a MIXED procedure in SAS 9.4. Horses in the TRT group had no increase in SAA during supplementation while horses in CON increased by approximately 37% by d42 for a trt x time interaction (P < 0.001). Horses in the CON group in both the control and challenged joint had higher AUC for interleukin-6 (P = 0.02) and tumor-necrosis factor α (P = 0.01) than TRT horses. Interleukin-6 and TNFa were analyzed via species-specific colorimetric assays (RD Systems). Taken together, these data indicate that ActivAge® supplementation reduced systemic inflammation in senior horses while also supporting these horses during a joint inflammation challenge.