Beta-glucans for Skin Disease, Osteoarthritis, IBD | Bernie’s

Amaral, A. R., Risolia, L. W., Rentas, M. F., Marchi, P. H., Balieiro, J. C. d. C., Vendramini, T. H. A., & Brunetto, M. A. (2024). Translating human and animal model studies to dogs’ and cats’ veterinary care: Beta-glucans application for skin disease, osteoarthritis, and inflammatory bowel disease management. Microorganisms, 12, 1071. https://doi.org/10.3390/microorganisms12061071

What This Paper Is About

The authors reviewed studies from 2020–2024 on beta-glucans and their application to skin disease, osteoarthritis, and IBD in dogs and cats, adding a few case reports where veterinary data were sparse. Their goal was to translate evidence from animal models and human research into practical considerations for veterinary care, while clearly stating where evidence is preliminary or inconsistent.

Why Beta-glucans Are Considered

Beta-glucans are polysaccharides found in yeast, mushrooms, algae, bacteria, and cereals. Structure matters: source and branching patterns influence solubility and biological effects. Yeast-derived 1,3/1,6-beta-glucans are recognized by receptors such as dectin-1 on immune cells and can modulate innate and adaptive immunity. Prior work in dogs has reported effects on immune markers, the fecal microbiota, and metabolic variables, motivating interest in chronic inflammatory conditions.

How the Authors Searched

The review drew from Embase and PubMed (2020–2024) and summarized veterinary, human, and experimental animal studies relevant to dogs and cats. Because direct veterinary evidence was limited for some topics (especially skin), the authors included three case reports to provide additional clinical context. A visual “map” of study types, routes, and durations appears in their Figure 1.

Skin Disease (Atopic Dermatitis)

Atopic dermatitis (AD) is a common inflammatory skin disease in dogs. The review highlights immunologic mechanisms (Th1/Th2 imbalance) and explains why beta-glucans have been tested orally and topically.

• In a double-blind, placebo-controlled dog study (8 weeks; 800 ppm yeast 1,3/1,6-beta-glucan in food), owners reported improvements in itch and skin signs versus baseline; when totals were summed, the beta-glucan group showed a 63% “extra improvement” compared with placebo, though some individual endpoints did not differ between groups.
• Small human and rodent studies cited by the authors (topical or oral) reported reduced lesion severity, pruritus, histamine, and edema, with signals of shifting immune responses toward more regulated patterns; these support biologic plausibility but are not a substitute for canine trials.
• Route appears important: an environmental exposure study in dogs linked dust endotoxin—but not beta-glucan levels—to lower AD risk, suggesting ingested or topical beta-glucans may act differently than ambient exposure.

Author emphasis: early canine data suggest beta-glucans can reduce clinical signs of AD, but small samples, mixed endpoints, product differences, and use within multimodal protocols limit firm conclusions. More controlled veterinary trials are needed.

Osteoarthritis

Osteoarthritis (OA) is prevalent in older dogs and causes pain and reduced mobility. The review discusses anti-inflammatory pathways (e.g., modulation of cytokines such as IL-6, TNF-α and mediators like PGE₂).

• In dogs, one randomized, double-blind trial (8 weeks; 800 ppm yeast 1,3/1,6-beta-glucan) reported significant improvements from baseline in activity and stiffness within the beta-glucan group, although between-group differences over time were not significant.
• In rodent OA models, oral beta-glucans (Aureobasidium pullulans–derived “Polycan”) reduced joint stiffness and cartilage damage and increased chondrocyte proliferation; a Polycan-calcium blend showed synergistic effects.
• A human RCT combining Polycan with glucosamine reduced WOMAC scores more than glucosamine alone, with no safety concerns at the tested doses.

Author emphasis: beta-glucans appear safe and potentially helpful for OA signs, but veterinary clinical evidence is scarce; larger, well-controlled trials in real-world settings are required before routine recommendations can be made.

Inflammatory Bowel Disease (IBD)

IBD in dogs and cats is diagnosed by mucosal inflammation after ruling out other causes; pathophysiology and immune profiles differ from human IBD. The review frames beta-glucans as prebiotics and immunomodulators that may support beneficial bacteria and generate short-chain fatty acids (SCFAs), while noting that outcomes can vary with source and context.

• In healthy dogs fed increasing yeast 1,3/1,6-beta-glucan for 140 days, phylum-level shifts occurred (e.g., Firmicutes increased at mid-dose; Bacteroidetes decreased), but fecal SCFAs did not change, and the authors caution that fecal SCFAs may not reflect colonic use.
• In dogs with IBD, small clinical studies cited in the review reported improved clinical indices or histology and shifts in cytokines (e.g., lower IL-6, higher IL-10) with beta-glucan–containing regimens; however, mixtures with other actives and small samples limit attribution to beta-glucan alone.
• Rodent IBD models show mixed results: some report protection with specific bacterial beta-glucans, while others found oral beta-glucans aggravated DSS-induced colitis—differences the authors attribute to glucan origin, molecular weight, and the inflammatory milieu.

Author emphasis: beta-glucans may help manage IBD via immune and microbiota pathways, but veterinary data are limited and not uniform. The authors call for trials that specify origin, molecular weight, dose, and disease stage to determine where and how beta-glucans are beneficial.

Bottom Line from the Authors

Beta-glucans are biological response modifiers with plausible mechanisms for skin, joint, and gut conditions in dogs and cats. Evidence summarized here suggests potential benefit and good tolerability, but current veterinary data are limited by small samples, heterogeneous products and dosing, and confounding co-treatments. The authors recommend randomized, double-blinded veterinary trials that use beta-glucans as the exclusive test intervention and carefully define type, dose, duration, and disease stage before making firm clinical recommendations.