Methylfolate modulates potassium evoked neuro-secretion: evidence for a role at the pteridine cofactor level of tyrosine 3-hydroxylase

Folic acid supplementation in postmenopausal women with hot flushes: phase III randomised double-blind placebo-controlled trial

OBJECTIVE

To assess whether folic acid supplementation ameliorates hot flushes.

DESIGN

Double-blind, placebo-controlled randomised trial.

SETTING

Nine hospitals in England.

POPULATION

Postmenopausal women experiencing ≥50 hot flushes weekly.

METHODS

Women (n = 164) were randomly assigned in a 1:1 ratio to receive folic acid 5 mg tablet or placebo daily for 12 weeks. Participants recorded frequency and severity of hot flushes in a Sloan Diary daily and completed Greene Climacteric and Utian Quality of Life (UQoL) Scales at 4-week intervals.

MAIN OUTCOME MEASURES

The change in daily Hot Flush Score at week 12 from randomisation based on Sloan Diary Composite Score B calculation.

RESULTS

Data of 143 (87%) women were available for the primary outcome. The mean change (SD) in Hot Flush Score at week 12 was -6.98 (10.30) and -4.57 (9.46) for folic acid and placebo group, respectively. The difference between groups in the mean change was -2.41 (95% CI -5.68 to 0.87) (P = 0.149) and in the adjusted mean change -2.61 (95% CI -5.72 to 0.49) (P = 0.098). Analysis of secondary outcomes indicated an increased benefit in the folic acid group regarding changes in total and emotional UQoL scores at week 8 when compared with placebo. The difference in the mean change from baseline was 5.22 (95% CI 1.16-9.28) and 1.88 (95% CI 0.23-3.52) for total and emotional score, respectively.

CONCLUSIONS

The study was not able to demonstrate that folic acid had a statistically significant greater benefit in reducing Hot Flush Score over 12 weeks in postmenopausal women when compared with placebo.

TWEETABLE ABSTRACT

Folic acid may ameliorate hot flushes in postmenopausal women but confirmation is required from a larger study.

Does Diet Matter? The Use of Polyunsaturated Fatty Acids (PUFAs) and Other Dietary Supplements in Inflammation-Associated Depression

An increasingly pertinent issue in psychiatry in recent years is that of the limitations of conventional antidepressants, which are not effective in a large number of patients with major depressive disorder (MDD). Coupled with emerging hypotheses about the role of inflammation in depression, it would appear that it is time to look for alternative treatments for these symptoms.This review will examine an emerging area in psychiatry, that of dietary supplements and the diet in general to treat depressive symptoms, and inflammation in depression. In particular, polyunsaturated fatty acids (PUFAs), probiotics and folic acid are three supplements that demonstrate the ability to target inflammation and other underlying systems in depression. While there is a definite need for more research in all these supplements to determine true efficacy, dosage and target populations, they can be used as mono- or adjunctive therapies to good effect, and show superior safety profiles when compared with more traditional alternatives.

Folic acid supplementation: The new dawn for postmenopausal women with hot flushes

Hot flushes, experienced by 75% of menopausal women, are associated with estrogen deprivation. Estrogen was shown to ameliorate hot flushes by interacting with monoamine neurotransmitters in the brain; reducing noradrenaline and increasing serotonin. Hormone replacement therapy (HRT), the first treatment option, causes concerns over possible increased risks particularly breast cancer. Folic acid is involved in the biosynthesis of serotonin and nordrenaline, which is responsible for its effects on mood and cognition, and degrees of folate inadequacy, not severe enough to produce megaloblastic anaemia, were found to be associated with depression and cognitive malfunctioning. Also, increased age was observed to relate to reduced serum and cerebrospinal fluid folic acid levels. There is emerging evidence that folic acid supplementation ameliorates hot flushes by the same mechanism as estrogen. To explore this hypothesis, a multi-centre, double-blind, placebo-controlled randomized is being set up to compare the effect of 5 mg folic acid vs placebo in reducing the frequency and severity of hot flushes in postmenopausal women, and on the blood level of serotonin and noradrenaline. If folic acid supplementation is demonstrated to be effective, this will be a turning point in the clinical practice since it represents a cheap, safe and well-tolerated alternative to HRT.

Folic acid supplementation may cure hot flushes in postmenopausal women: a prospective cohort study

BACKGROUND

Neurotransmitter norepinephrine seems to be involved in the pathophysiology of hot flushes in postmenopausal women, and folic acid was found to interact with its receptors.

OBJECTIVES

To examine the effect of folic acid supplementation on the occurrence of hot flushes and the plasma level of 3-methoxy 4-hydroxy phenyl glycol (MHPG, the main metabolite of brain norepinephrine).

METHOD

Forty-six postmenopausal women were allocated (by alternation) into 2 groups (n = 23 each); Group 1 received folic acid 5mg tablets daily for 4 weeks and group 2 received placebo tablets. Four women in group 2 discontinued the study.

RESULTS

The number of women who reported improvement in hot flushes was significantly higher in the treatment group. On comparing the mean plasma levels of MHPG before and after treatment, a significant lowering was found in the treatment group (mean % change = -24.1 +/- 17.9, p < 0.001) when compared with the placebo-control group (mean % change = -5.59 +/- 16.4, p = 0.10). In the treatment group, there was a significant negative correlation between improvement in hot flushes and the plasma level of MHPG (r = -0.453, p = 0.03).

CONCLUSION

Folic acid supplementation may cause subjective improvement of hot flushes by lowering the increased central noradrenergic activity.

Folic acid supplementation cures hot flushes in postmenopausal women

Over the past four decades, it was found that folic acid supplementation produced an antidepressant-like effect mediated by interaction with the brain noradrenergic receptors (inhibitory effect) and serotonergic receptors (stimulatory effect). Hot flushes occur in postmenopausal women because of disturbances in the thermoregulatory centre, most likely as a result of estrogen deficiency-related increase in central noradrenergic activity and reduced serotonergic activity. Therefore, we hypothesize that folic acid supplementation may ameliorate hot flushes by the same mechanism as estrogen replacement, i.e., by interacting with monoamine neurotransmitters in the brain; namely norepinephrine and serotonin. This article discusses the hypothesis and presents supportive preliminary data.

L-methylfolate in the Therapeutic Management of Major Depressive Disorder

Optimal levels of the bioactive folate are necessary for maintaining proper brain and body functioning. Folate deprivation and impaired folate metabolism are clinically associated with defects in the developing nervous system. Numerous studies implicate a deficiency of bioactive folate with an increased risk of major depressive disorder and other neuropsychiatric disorders. Bioactive forms of folate, particularly L-methylfolate, have been found to augment the therapeutic efficacy of antidepressants in patients with major depressive disorder, who fail to adequately respond to standard therapies. The antidepressant action of L-methylfolate appears to improve treatment outcomes most effectively when administered as an adjuvant to traditional antidepressants. This new understanding of the role of folates in major depressive disorder and other mood disorders offers opportunities to improve treatment outcomes.

Novel therapeutics for depression: L-methylfolate as a trimonoamine modulator and antidepressant-augmenting agent

Folate deficiency may increase the risk of depression and reduce the action of antidepressants. Individuals with an inherited polymorphism that reduces the efficiency of folate formation may be at high risk for folate deficiency and for major depression. Antidepressant effects have been reported when antidepressants are augmented with folic acid, folinic acid, or the centrally active L-methylfolate (known formally as (6(S)-5-methyltetrahydrofolate [MTHF]), particularly in depressed patients with folate deficiency whose major depressive episodes have failed to respond to antidepressants. The putative mechanism of action of MTHF as an augmenting agent to antidepressants is that it acts as a trimonoamine modulator (TMM), enhancing the synthesis of the three monoamines: dopamine (DA), norepinephrine (NE), and serotonin (5-HT), resulting in a boost to the efficacy of antidepressants.

The assays of activities and function of TH, AADC, and GCH1 and their potential use in ex vivo gene therapy of PD

In the past decades, there have been numerous studies in the gene therapy for Parkinson's disease (PD), especially in delivering genes of enzymes for dopamine (DA) synthesis. Gene therapy in PD appears to be at the brink of the clinical study phase. However, there are many questions that need to be solved before this approach can be contemplated clinically, especially the question about the control of DA production because too much DA could cause toxicity. Until recently, few studies have investigated the relation between DA production and PD improvement and respective expressed human tyrosine hydroxylase (hTH), human GTP-cyclohydrolase 1 (hGCH1), and human aromatic acid decarboxylase (hAADC) in ex vivo gene therapy for PD. Now, we have developed a simple, fast, and reliable method to assay the activities of TH and AADC and have provided the possibility of ex vivo gene therapy for PD by genetically modifying cells with separate hTH, hGCH1, and hAADC genes. Using the method, we found though hTH, hGCH1, and hAADC genes were expressed, respectively, they could fulfil the function of DA synthesis by incubating together in vitro, and more DA was synthesized in vitro when hTH, hGCH1, and hAADC genes were expressed together rather than hTH and hAADC genes expressed or hTH expressed. The result suggests that we could easily control DA production in ex vivo gene therapy before transplantation. By combining this method and microdialysis, we also could further investigate the DA production in vitro and in vivo and then decide the optimal number and ratio of different transduced cells to improve the therapy of PD. Thus, the method has potential use in ex vivo gene therapy of PD.

Homocysteine, folate, methylation, and monoamine metabolism in depression

OBJECTIVES

Previous studies suggest that folate deficiency may occur in up to one third of patients with severe depression, and that treatment with the vitamin may enhance recovery of the mental state. There are, however, difficulties in interpreting serum and red cell folate assays in some patients, and it has been suggested that total plasma homocysteine is a more sensitive measure of functional folate (and vitamin B12) deficiency. Other studies suggest a link between folate deficiency and impaired metabolism of serotonin, dopamine, and noradrenaline (norepinephrine), which have been implicated in mood disorders. A study of homocysteine, folate, and monoamine metabolism has, therefore, been undertaken in patients with severe depression.

METHODS

In 46 inpatients with severe DSM III depression, blood counts, serum and red cell folate, serum vitamin B12, total plasma homocysteine, and, in 28 patients, CSF folate, S-adenosylmethionine, and the monoamine neurotransmitter metabolites 5HIAA, HVA, and MHPG were examined. Two control groups comprised 18 healthy volunteers and 20 patients with neurological disorders, the second group undergoing CSF examination for diagnostic purposes.

RESULTS

Twenty four depressed patients (52%) had raised total plasma homocysteine. Depressed patients with raised total plasma homocysteine had significant lowering of serum, red cell, and CSF folate, CSF S-adenosylmethionine and all three CSF monoamine metabolites. Total plasma homocysteine was significantly negatively correlated with red cell folate in depressed patients, but not controls.

CONCLUSIONS

Utilising total plasma homocysteine as a sensitive measure of functional folate deficiency, a biological subgroup of depression with folate deficiency, impaired methylation, and monoamine neurotransmitter metabolism has been identified. Detection of this subgroup, which will not be achieved by routine blood counts, is important in view of the potential benefit of vitamin replacement.