Enzymatic and nonenzymatic oxidation of polyunsaturated fatty acids leads to the formation of biologically active products known as lipid mediators. In the brain, lipid mediators play an important role in supporting homeostasis and normal function. Thus, levels of these metabolites in normal and pathologic conditions in the brain are particularly relevant in understanding the transition to disease.

In this study, liquid chromatography tandem mass spectrometry was used to analyze lipid mediators in cerebrospinal fluid (CSF) of controls and traumatic brain injured (TBI) patients.

Our results showed that the levels of arachidonic acid (AA), docosahexaenoic acid (DHA), 5- and 12- eicosatetraenoic acid (HETE) were significantly increased in the CSF of TBI patients. The magnitude of increase was 10-fold for AA, DHA, and 5-HETE and 17-fold for 12-HETE. Prostaglandins and leukotrienes were not detected in CSF of either control or brain injured patients. Furthermore, this study found that isoprostanes and thromboxanes are present in CSF of brain injured patients.

This study clearly shows that certain lipid mediators accumulate in the CSF of TBI patient. This study also suggests the potential use of DHA, AA, 5- and 12-HETE as biochemical markers of brain injury and to monitor the impact of interventions.