Rosiglitazone in the thawing medium improves mitochondrial function in stallion spermatozoa through regulating Akt phosphorylation and reduction of caspase 3.

The research paper is about the examination of rosiglitazone’s role in enhancing the functionality of thawed stallion spermatozoa by regulating its mitochondrial functions and reducing caspase 3 activity.

Study Purpose and Hypothesis

• The aim of this research was to explore the potential benefits of rosiglitazone supplementation on thawed stallion spermatozoids, a population known for experience compromised mitochondrial function and accelerated senescence after thawing.
• The study was based on the hypothesis that thawed sperm might benefit from rosiglitazone supplementation, which has been proven to enhance the glycolytic capability of stallion spermatozoids at ambient temperature.

Methodology and Testing

• The study used thawed sperm that were washed and resuspended in Tyrodes media, divided into portions, and supplemented with either no rosiglitazone or a 75 μM dose of rosiglitazone.
• The sperm were then incubated for one and two hours before evaluating their mitochondrial functionality, Akt phosphorylation, and caspase 3 activity.
• Additional samples were tested by incubating in the presence of an Akt1/2 inhibitor, compound C (an AMPK inhibitor), or GW9662 (an antagonist of the PPARγ receptor), to study the effects of these inhibitors.

Key Findings

• The results showed that rosiglitazone maintained Akt phosphorylation and reduced caspase 3 activation, both measurable effects that were prevented by incubating in the presence of the three aforementioned inhibitors.
• Rosiglitazone also boosted mitochondrial functionality, improving the overall condition and potential viability of the thawed stallion spermatozoa.

Conclusions and Implications

• This research provides the first evidence that the functionality of frozen stallion spermatozoa may be potentially improved post-thaw via the activation of pro-survival pathways.
• These findings offer fresh insights for improving current sperm biotechnology, specifically in the context of stallions. The use of rosiglitazone could help to mitigate the impacts of thawing on sperm wellbeing, thus enhancing the successful outcomes of artificial insemination procedures in horses.