Determination of serum miRNA-124 expression levels before and after sedation in patients receiving intravenous ketamine

This thesis aimed to show the effects of intravenous ketamine on miRNA-124 and SOCS3 protein expression in subjects undergoing surgical procedures under sedoanalgesia. Ketamine modulates inflammation by reducing inflammatory cytokines, including in the central nervous system. By suppressing the effects of pro-inflammatory cytokines, SOCS3 helps prevent the excessive response to inflammation, therefore maintaining immune homeostasis. Ketamine's ability to reduce inflammation may be partly linked to SOCS3 expression. Blood samples were collected from 20 patients before and after ketamine administration, therefore 40 serum samples analysed. Although no difference was found between the SOCS3 values before and after ketamine administration, the average SOCS3 increased by 2.18 times after ketamine application. On the other hand, a significant difference was found between the miRNA-124 (2^(-ΔΔCT)) values before and after the ketamine (p=0.0172), with the average miRNA-124 increasing by 9.2 times after the ketamine treatment. Sensitivity and specificity calculations for various cut-off values of miRNA-124 expression(2^(-ΔΔCT)) for predicting before and after ketamine treatment status, and the optimum cutoff value for miRNA-124 are presented in Table 4. An empirical ROC curve corresponding to these findings yielding an AUC of 0.71 (95% CI: 0.541-0.879; p<0.001) was generated (figure 16). ROC curve for miRNA-124 indicates that the ROC data possesses an excellent predictive ability in distinguishing before and after ketamine treatment. A ROC curve corresponding to the SOCS3 values yielding an AUC of 0.604 (95%CI of 0.393-0.165) was generated, as well (figure 17). The AUC value of 0.604 for SOCS3 protein indicates a mild predictive capacity to distinguish patients from before and after ketamine treatment. Our study has shown that subanesthetic doses of ketamine increased SOCS3 protein levels by 2.18-fold compared to baseline. Furthermore, ketamine increased both blood miRNA¬-124 expression (2^(-ΔΔCT)) and SOCS3 protein levels significantly from baseline values; their sensitivity and specificity to predict ketamine's effect was prominent, with a ROC value of 0.71 and 0.60.