Introduction: Bipolar disorder (BD) is a chronic disorder associated
with significant psychiatric morbidity and disability. Recent research
has linked inflammatory processes to the pathology of BD. Resolvin D1
(RvD1), an anti-inflammatory molecule derived from eicosapentaenoic
acid (EPA) and docosahexaenoic acid (DHA), has been shown to inhibit
apoptosis and neuroinflammation, and promote neurogenesis. This
study aims to determine changes in serum RvD1 levels between acute
episode and euthymic periods in patients with BD and their association
with inflammatory and metabolic syndrome (MetS) parameters.
Methods: This prospective clinical study was conducted with patients
diagnosed with BD-I according to SCID-5. Patients whose serum RvD1
levels were assessed during manic and depressive episodes in the
previous study were invited to return to the study after at least 8 weeks,
when they had reached the euthymic period. Blood samples for RvD1,
C-reactive protein (CRP), and hemogram tests were collected during
both acute episodes and remission periods.
Results: The study included 32 patients in manic episodes, 27 in
depressive episodes, and 41 healthy controls, with no significant age
difference among the groups. RvD1 levels decreased significantly from
manic episodes to complete remission period (p=0.017, z=-2.391) during
follow-up. The decrease from depression to remission was not statistically
significant. Serum RvD1 levels in patients with depressive episodes in
remission remained high in the control group (p=0.581, z=-0.553). During
the follow-up period, white blood cell (p=0.009, z=-2.606) and neutrophil
(p=0.007, z=-2.693) in mania period and CRP values in depression period
(p=0.004, z=-2.880) were found to have decreased statistically.
Conclusions: The study indicates that serum RvD1 levels are elevated
during manic and depressive episodes in BD patients compared to
healthy controls and decrease significantly during the remission period
in patients with manic episode. We propose the potential utility of RvD1
as a diagnostic marker for identifying manic and depressive states. We
can assume that there is an inflammatory process in BD in which RvD1
also plays a role. Further research is needed to explore the therapeutic
potential of targeting RvD1 pathways in BD treatment.
Keywords: Axonal degeneration, bipolar disorder, metabolic syndrome,
neuroinflammation, resolvin D1