Triiodothyronine Has No Enhancement Effect on the Osteogenic or Chondrogenic Differentiation of Equine Adipose Tissue Stem Cells.
Authors: Oliveira Spila Débora de, Maranhão Renata de Pino Albuquerque, Ocarino Natália de Melo, de Lima Jorge Tiburcio Barbosa, Melo Fabrício Gomes, Boeloni Jankerle Neves, Serakides Rogéria
Journal: Journal of equine veterinary science
Summary
# Editorial Summary Researchers evaluated whether triiodothyronine (T3), a thyroid hormone with known metabolic effects, could enhance bone or cartilage formation from equine adipose-derived mesenchymal stem cells (AD-MSCs)—a promising source for regenerative medicine in musculoskeletal injuries. Using two T3 concentrations (0.01 and 1,000 nM) across 21-day osteogenic and 14-day chondrogenic differentiation protocols, the team measured alkaline phosphatase activity, cell viability, mineralised nodule formation, and matrix synthesis through established in vitro assays. Contrary to expectations, T3 demonstrated no beneficial effects; instead, results were inconsistent and frequently detrimental—the lower concentration (0.01 nM) reduced cell density and mineralised nodule formation by Day 14 despite paradoxical increases in enzyme activity, whilst the higher concentration (1,000 nM) suppressed mitochondrial metabolism and chondrogenic matrix synthesis. For equine practitioners exploring stem cell therapies for bone or cartilage repair, these findings suggest that T3 supplementation offers no advantage and may actually compromise cell performance and tissue matrix development depending on concentration and timing, arguing against its use as an adjunct to AD-MSC-based regenerative protocols in clinical applications.
Read the full abstract on PubMed
Practical Takeaways
- •T3 supplementation does not improve stem cell-based bone or cartilage regeneration therapies in horses and may be counterproductive at certain concentrations
- •If considering thyroid hormone modulation in regenerative medicine protocols for equine patients, this research suggests it does not enhance osteogenic or chondrogenic outcomes
- •This in vitro finding suggests alternative approaches or adjuvant factors should be investigated for enhancing mesenchymal stem cell differentiation in equine bone and cartilage repair
Key Findings
- •Triiodothyronine (T3) at 0.01 nM reduced cell density and mineralized nodule formation at Day 14 despite increased ALP activity
- •T3 at 1,000 nM concentration reduced mitochondrial metabolism and cell density at Day 21 in osteogenic cultures
- •Higher T3 concentration (1,000 nM) reduced mitochondrial metabolism, ALP activity, cell density, and chondrogenic matrix percentage at Day 14
- •T3 supplementation showed no enhancement effect on osteogenic or chondrogenic differentiation of equine adipose-derived mesenchymal stem cells and may negatively affect cell density and matrix synthesis