Influence of commonly used pharmaceutical agents on equine bone marrow-derived mesenchymal stem cell viability.

This research investigates how certain drugs can affect the viability and proliferation of mesenchymal stem cells (MSCs) in horses. The study suggests that while some sedatives and local anesthetics do not significantly impact MSCs, certain corticosteroids can severely affect stem cell viability.

Objective and Methodology

• The main aim of this research is to understand the influence of various pharmaceutical agents—specifically sedatives, local anaesthetics, and corticosteroids—on the viability and proliferation of MSCs in comparison to tendon-derived somatic cells (TDCs).
• In the process, the researchers conducted in vitro cell cultures involving MSCs and TDCs, which were grown in media containing clinically relevant dose ranges of drugs such as xylazine, romifidine, detomidine, butorphanol, mepivacaine, methylprednisolone, and triamcinolone acetonide.
• Sample viability in suspension culture was periodically assessed within a four-hour window using a method known as the trypan blue dye assay. MSCs growing in a monolayer culture exposed to the highest drug concentrations were checked for proliferation with the alamarBlue fluorescence assay.

Results

• The research found that exposure to romifidine or mepivacaine did not significantly impact either the viability or the proliferation rate of MSCs or TDCs, regardless of the dosage used.
• The highest concentration of detomidine and butorphanol significantly reduced MSC viability compared to the control instances. Also, although xylazine exposure led to a significant dose-dependent reduction in MSC viability, overall population viability remained acceptable.
• On the contrary, both methylprednisolone and triamcinolone induced rapid death in a significant number of MSCs.

Conclusions

• One of the critical conclusions of this study is that clinicians can administer nerve blocks and sedate horses during intratendinous or intrathecal injection of MSCs without worrying about the impacts of these drugs on cell viability.
• However, the use of corticosteroids in conjunction with MSCs is strongly discouraged as they could be severely detrimental to cell viability.
• Therefore, steroid administration within the sheath of a damaged tendon is not recommended.