The Effects of Cortisol on Blood Coagulation in Zebrafish

By Bailey Bashara

Faculty Mentor: Professor Dianne Baker

In humans, increased cortisol can lead to pathological increases in blood coagulation, in turn leading to thrombotic events such as deep vein thrombosis and pulmonary emboli. Cortisol appears to promote coagulation by upregulating the transcription of coagulation factors, thereby increasing the likelihood of the coagulation cascade. It is possible that cortisol has a similar effect on clotting in zebrafish, via effects on transcription of coagulation factors. If so, this would support the use of zebrafish as a model organism for testing anti-coagulant medications. I hypothesized that cortisol induces transcriptional upregulation of genes encoding coagulation factors in zebrafish, as in humans. Additionally, that transcript levels of the coagulation factor genes will be higher in stressed females than stressed males. Male and female zebrafish (n=34) were exposed to acute stressors for 7 days, resulting in an unpredictable chronic stress environment. Additional males and females (n=34) were not exposed to the stress environment and were used as control. Twenty-four hours after the seven-day treatment, the fish were euthanized, and their livers transferred to TriReagent. The RNA from the livers was isolated and cDNA synthesized for qPCR. qPCR measured transcript levels of clotting factors X and VII. Mean (SE) Factor VII transcript levels of the control group (-0.211) were not significantly different from stressed groups (-0.367), nor in Factor X control group (-0.100) and stressed groups (-0.576) (p>0.05). Difference in transcript levels between each sex were also determined, with no significant difference in Factor VII control females (0.063), stressed females (-0.583), control males (-0.063), or stressed males (-0.004). No significant difference was found between transcript levels of Factor X control females (0.051), stressed females (-1.361), control males (0.1) or stressed males (0.122) (p>0.05). There is no evidence that increased cortisol causes differences in the transcription of genes coding for coagulation Factors VII or X.

3 Replies to “The Effects of Cortisol on Blood Coagulation in Zebrafish”

  1. Bailey – thank you for sharing your research. Are the fish stressed alone or in a group? Do you think that would make a difference in your studies?

  2. Hi Bailey,

    I found your research to be very interesting! Thank you for sharing. I am very interested in endocrine disorders in humans, Cushing’s in particular. Initially I was already interested to hear if Cushing’s had any impact on coagulation factors, so I was happy when you answered that in your presentation. Great job!

  3. This was really cool to watch and read! It was really informative and well put together!

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