ABSTRACT
BACKGROUND: Retina is considered as a window to the brain due to the similarities in terms of development and pathologies. Optical coherence tomography (OCT) can perform quantitative examinations in the retina. In this study, we aimed to investigate the effects of drugs used in schizophrenia and bipolar disorder (BD) on retinal nerve fiber layer (RNFL) and macular thickness. SUBJECTS AND METHODS: The study included schizophrenia (n=35) and euthymic BD (n=46) patients on various medications, and age, gender matched healthy control group (n=31). For retinal evaluation, measurements of RNFL and macula were performed with Optovue RTVue Premier OCT. RESULTS: In the schizophrenia group, chlorpromazine equivalent dose of antipsychotics was a statistically significant negative predictor of left RNFL nasal superior region thickness. In the BD group, serum valproate level was a significant positive predictor of thickness in the right macular inferior outer, left macular nasal outer region, right RNFL inferotemporal, left temporal and inferotemporal regions. CONCLUSION: Since the retina consists of neurons, morphological or functional examination of retina may be beneficial for the evaluation of the effects of psychopharmalogical treatments in schizophrenia and BD. The outcome of this study implies that valproate has neuroprotective effects on the optic nerve and macula, and this finding is consistent with the literature implying neurotrophic effects of valproate.
Subject(s)
Bipolar Disorder/diagnostic imaging , Bipolar Disorder/drug therapy , Retina/drug effects , Retina/diagnostic imaging , Schizophrenia/diagnostic imaging , Schizophrenia/drug therapy , Tomography, Optical Coherence , Adult , Female , Humans , Macula Lutea/diagnostic imaging , Macula Lutea/drug effects , Male , Nerve Fibers/drug effectsABSTRACT
The ability of the brain to reduce the amount of trivial or redundant sensory inputs is called gating function. Dysfunction of sensory gating may lead to cognitive fragmentation and poor real-world functioning. The auditory dual-click paradigm is a pertinent neurophysiological measure of sensory gating function. This meta-analysis aimed to examine the subcomponents of abnormal P50 waveforms in bipolar disorder and schizophrenia to assess P50 sensory gating deficits and examine effects of diagnoses, illness states (first-episode psychosis vs. schizophrenia, remission vs. episodes in bipolar disorder), and treatment status (medication-free vs. medicated). Literature search of PubMed between Jan 1st 1980 and March 31st 2019 identified 2091 records for schizophrenia, 362 for bipolar disorder. 115 studies in schizophrenia (4932 patients), 16 in bipolar disorder (975 patients) and 10 in first-degree relatives (848 subjects) met the inclusion criteria. P50 sensory gating ratio (S2/S1) and S1-S2 difference were significantly altered in schizophrenia, bipolar disorder and their first-degree relatives. First-episode psychosis did not differ from schizophrenia, however episodes altered P50 sensory gating in bipolar disorder. Medications improve P50 sensory gating alterations in schizophrenia significantly and at trend level in bipolar disorder. Future studies should examine longitudinal course of P50 sensory gating in schizophrenia and bipolar disorder.
Subject(s)
Bipolar Disorder/physiopathology , Electroencephalography , Evoked Potentials, Auditory/physiology , Schizophrenia/physiopathology , Sensory Gating/physiology , Adult , Brain/physiopathology , Female , Humans , MaleABSTRACT
Bipolar disorder is a chronic disease characterized by recurring episodes of mania and depression that can lead to disability. This study investigates the protective effects of edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one), a drug with well-known antioxidant properties, in a model of mania induced by ketamine in rats. Locomotor activity was assessed in the open-field test. Superoxide dismutase (SOD), catalase (CAT) and thiobarbituric acid reactive substances (TBARS) levels were measured in order to evaluate oxidative damage in the rat hippocampus and prefrontal cortex. Increased locomotor activity (hyperlocomotion) was observed at the open-field test with ketamine treatment (25 mg/kg, i.p., 8 days). Edaravone (18 mg/kg) treatment did not prevent hyperlocomotion in the mania model induced with ketamine in rats, but lithium chloride (47.5 mg/kg, i.p., positive control) did prevent hyperlocomotion. Edaravone and lithium chloride treatments were found to reduce the increase in SOD and CAT activity following ketamine administration in a non-significant manner but caused no change in TBARS levels.
