Exploratory study of ultraviolet B (UVB) radiation and age of onset of bipolar disorder.

BACKGROUND: Sunlight contains ultraviolet B (UVB) radiation that triggers the production of vitamin D by skin. Vitamin D has widespread effects on brain function in both developing and adult brains. However, many people live at latitudes (about > 40 N or S) that do not receive enough UVB in winter to produce vitamin D. This exploratory study investigated the association between the age of onset of bipolar I disorder and the threshold for UVB sufficient for vitamin D production in a large global sample. METHODS: Data for 6972 patients with bipolar I disorder were obtained at 75 collection sites in 41 countries in both hemispheres. The best model to assess the relation between the threshold for UVB sufficient for vitamin D production and age of onset included 1 or more months below the threshold, family history of mood disorders, and birth cohort. All coefficients estimated at P ≤ 0.001. RESULTS: The 6972 patients had an onset in 582 locations in 70 countries, with a mean age of onset of 25.6 years. Of the onset locations, 34.0% had at least 1 month below the threshold for UVB sufficient for vitamin D production. The age of onset at locations with 1 or more months of less than or equal to the threshold for UVB was 1.66 years younger. CONCLUSION: UVB and vitamin D may have an important influence on the development of bipolar disorder. Study limitations included a lack of data on patient vitamin D levels, lifestyles, or supplement use. More study of the impacts of UVB and vitamin D in bipolar disorder is needed to evaluate this supposition.

Curcumin as Add-On to Antipsychotic Treatment in Patients With Chronic Schizophrenia: A Randomized, Double-Blind, Placebo-Controlled Study.

BACKGROUND: Introduction of old and new generations of antipsychotics leads to significant improvements in the positive symptoms of schizophrenia. However, negative symptoms remain refractory to conventional trials of antipsychotic therapy. Recently, there were several open clinical human trials with curcumin. Curcumin is a natural polyphenol, which has a variety of pharmacological activities, including antioxidative and neuroprotective effects. The studies showed that curcumin improved the negative symptoms of schizophrenia. The purpose of our study was to examine the efficacy of curcumin as an add-on agent to regular antipsychotic medications in patients with chronic schizophrenia. METHODS: Thirty-eight patients with chronic schizophrenia were enrolled in a 24-week, double-blind, randomized, placebo-controlled study. The subjects were treated with either 3000 mg/d curcumin or placebo combined with antipsychotics from January 2015 to February 2017. The outcome measures were the Positive and Negative Symptoms Scale (PANSS) and the Calgary Depression Scale for Schizophrenia. RESULTS: Analysis of variance showed significant positive changes in both groups from baseline to the end of the study in all scales of measurement. There was a significant response to curcumin within 6 months in total PANSS (P = 0.02) and in the negative symptoms subscale (P = 0.04). There were no differences in the positive and general PANSS subscales, and the Calgary Depression Scale for Schizophrenia scores between the treatment and placebo groups. No patient complained of any adverse effect. CONCLUSIONS: The promising results of curcumin as an add-on to antipsychotics in the treatment of negative symptoms may open a new and safe therapeutic option for the management of schizophrenia. However, these results should be replicated in further studies.ClinicalTrials.gov Identifier: NCT02298985.

Curcumin as an add-on to antidepressive treatment: a randomized, double-blind, placebo-controlled, pilot clinical study.

OBJECTIVES: Depression is a widespread mental disorder in which nearly half of the affected people have recurrent symptoms. Drug combinations may produce cumulative adverse effects, especially in elderly and physically ill patients. It was demonstrated that curcumin possesses antidepressive activity in various animal models of depression, and a combination of curcumin with some antidepressants potentiates the antidepressive effect of these agents. We sought to evaluate the efficacy of curcumin as an antidepressive agent in a combination with other antidepressants in patients with major depression. METHODS: Forty patients with a first episode of depression participated in a 5-week, double-blind, randomized, placebo-controlled study. The subjects were treated with either 500-mg/d curcumin or placebo together with antidepressants (escitalopram or venlafaxine) during August 2010 until June 2011. The outcome measures were Clinical Global Impression-Severity Scale, Hamilton Depression Rating Scale, and Montgomery-Asberg Depression Rating Scale. RESULTS: Analysis of variance showed significant positive changes in both groups from baseline to the end of the study in all scales of measurement. These changes became significant from the first visit after 7 days of treatment. There was no difference between curcumin and placebo, which means negative results. However, the patients in the curcumin group demonstrated a trend to a more rapid relief of depressive symptoms in comparison to those in the placebo group. None of the patients complained of any adverse effect during the study. CONCLUSIONS: Although there is no definitive proof that curcumin can induce an earlier beneficial effect of antidepressive agents, it seems like an extended study is needed to prove it, using higher therapeutic doses of curcumin.

Homozygote inositol transporter knockout mice show a lithium-like phenotype.

OBJECTIVE: Lithium inhibits inositol monophosphatase and also reduces inositol transporter function. To determine if one or more of these mechanisms might underlie the behavioral effects of lithium, we studied inositol transporter knockout mice. We previously reported that heterozygous knockout mice with reduction of 15-37% in brain inositol had no abnormalities of pilocarpine sensitivity or antidepressant-like behavior in the Porsolt forced swim test. We now report on studies of homozygous inositol transporter knockout mice. METHODS: Homozygote knockout mice were rescued by 2% inositol supplementation to the drinking water of the dam mice through pregnancy and lactation. Genotyping was carried out by polymerase chain reaction followed by agarose electrophoresis. Brain free myo-inositol levels were determined gas-chromatographically. Motor activity and coordination were assessed by the rotarod test. Behavior of the mice was studied in lithium-pilocarpine seizure models for lithium action and in the Porsolt forced swim test model for depression. RESULTS: In homozygote knockout mice, free inositol levels were reduced by 55% in the frontal cortex and by 60% in the hippocampus. There were no differences in weight or motor coordination by the rotarod test. They behaved similarly to lithium-treated animals in the model of pilocarpine seizures and in the Porsolt forced swimming test model of depression. CONCLUSIONS: Reduction of brain inositol more than 15-37% may be required to elicit lithium-like neurobehavioral effects.

Neuropsychological correlates of homocysteine levels in euthymic bipolar patients.

BACKGROUND: We have previously reported that homocysteine levels are elevated in euthymic bipolar patients with functional deterioration. The current study was designed to extend this finding by examining the relationship between neuropsychological functioning and homocysteine levels in euthymic bipolar patients. METHODS: Fifty-seven euthymic bipolar outpatients were assessed for serum levels of homocysteine, folic acid, and vitamin B-12 and administered a battery of neuropsychological tests. RESULTS: We found that male bipolar subjects showed higher average homocysteine levels than a comparison group of normal subjects, that poorer functioning on a task of executive function (Wisconsin Card Sort) was related to higher homocysteine levels, and that folic acid or vitamin B-12 levels did not significantly affect neuropsychological functioning. LIMITATIONS: These results, while suggesting some relationship between higher homocysteine levels, bipolar illness, and impairment in cognitive function do not establish any causative effects. CONCLUSIONS: The findings of this study confirm that in euthymic bipolar patients, higher homocysteine levels are associated with poorer performance in some neuropsychological tests. Treatment trials will be required before it will be known if the putative decrements in the executive function of bipolar patients can be reversed, or at least retarded, if homocysteine levels are reduced (as, for example, by dietary addition of B vitamin supplements).

IMPA1 is essential for embryonic development and lithium-like pilocarpine sensitivity.

Lithium has been the standard pharmacological treatment for bipolar disorder over the last 50 years; however, the molecular targets through which lithium exerts its therapeutic effects are still not defined. We characterized the phenotype of mice with a dysfunctional IMPA1 gene (IMPA1-/-) to study the in vivo physiological functions of IMPA1, in general, and more specifically its potential role as a molecular target in mediating lithium-dependent physiological effects. Homozygote IMPA1-/- mice died in utero between days 9.5 and 10.5 post coitum (p.c.) demonstrating the importance of IMPA1 in early embryonic development. Intriguingly, the embryonic lethality could be reversed by myo-inositol supplementation via the pregnant mothers. In brains of adult IMPA1-/- mice, IMPase activity levels were found to be reduced (up to 65% in hippocampus); however, inositol levels were not found to be altered. Behavioral analysis of the IMPA1-/- mice indicated an increased motor activity in both the open-field test and the forced-swim test as well as a strongly increased sensitivity to pilocarpine-induced seizures, the latter supporting the idea that IMPA1 represents a physiologically relevant target for lithium. In conclusion the IMPA1-/- mouse represents a novel model to study inositol homeostasis, and indicates that genetic inactivation of IMPA1 can mimic some actions of lithium.

Human MIP synthase splice variants in bipolar disorder.

OBJECTIVES: Alternative splicing allows the production of multiple gene products with different functions from a given sequence, affecting cellular function control. Tissue-specific splicing is most prevalent in the brain. We therefore investigate whether splice variants contribute to complex psychiatric disorders. A database search suggested that the myo-inositol-1-phosphate (MIP) synthase gene, possibly involved in pathophysiology of bipolar disorder, has splice variants. METHODS: Human RNA was purified from lymphocytes and postmortem brain. MIP synthase alternative splice variants were amplified using reverse transcription-polymerase chain reaction. RESULTS: The bioinformatics finding was confirmed in both tissues. No difference in lymphocyte MIP synthase mRNA splice-variant levels was found between bipolar patients and controls. However, patients with family history of a major psychiatric disorder had significantly higher levels of the variant lacking exons 3 and 4 versus patients with no family history and controls. CONCLUSIONS: As alternative splicing may be a mechanism by which the approximately 30,000 genes are amplified in mammalian brain, further studies with other candidate genes for psychiatric disorders are needed.

Inositol deficiency diet and lithium effects.

OBJECTIVES: A major hypothesis explaining the therapeutic effect of lithium (Li) in mania is depletion of inositol via inhibition of inositol monophosphatase. However, inositol is also present in the diet. Restriction of dietary inositol could theoretically enhance the effects of Li. METHODS: We used dietary inositol restriction in animal studies and also devised a palatable diet for humans that is 90% free of inositol. RESULTS: Dietary inositol restriction significantly augmented the inositol-reducing effect of Li in rat frontal cortex. Li reduced inositol levels by 4.7%, inositol-deficient diet by 5.1%, and Li plus inositol-deficient diet by 10.8%. However, feeding with the inositol-deficient diet did not enhance the behavioral effect of Li in the Li-pilocarpine seizure model. Fifteen patients participated in an open clinical study of the inositol-deficient diet: six rapid cycling bipolar patients responding inadequately to Li or valproate in different phases of illness; two Li-treated bipolar outpatients with residual symptomatology, and seven inpatient Li-treated bipolar patients in non-responding acute mania. The diet had a major effect in reducing the severity of affective disorder in 10 of the patients within the first 7-14 days of treatment. CONCLUSION: These results suggest that dietary inositol restriction may be useful in some bipolar patients, but controlled replication is necessary.