Combination pharmacotherapy for the treatment of fibromyalgia in adults

BACKGROUND

Fibromyalgia is a chronic widespread pain condition affecting millions of people worldwide. Current pharmacotherapies are often ineffective and poorly tolerated. Combining different agents could provide superior pain relief and possibly also fewer side effects.

OBJECTIVES

To assess the efficacy, safety, and tolerability of combination pharmacotherapy compared to monotherapy or placebo, or both, for the treatment of fibromyalgia pain in adults.

SEARCH METHODS

We searched CENTRAL, MEDLINE, and Embase to September 2017. We also searched reference lists of other reviews and trials registries.

SELECTION CRITERIA

Double-blind, randomised controlled trials comparing combinations of two or more drugs to placebo or other comparators, or both, for the treatment of fibromyalgia pain.

DATA COLLECTION AND ANALYSIS

From all studies, we extracted data on: participant-reported pain relief of 30% or 50% or greater; patient global impression of clinical change (PGIC) much or very much improved or very much improved; any other pain-related outcome of improvement; withdrawals (lack of efficacy, adverse events), participants experiencing any adverse event, serious adverse events, and specific adverse events (e.g. somnolence and dizziness). The primary comparison was between combination and one or all single-agent comparators. We also assessed the evidence using GRADE and created a 'Summary of findings' table.

MAIN RESULTS

We identified 16 studies with 1474 participants. Three studies combined a non-steroidal anti-inflammatory drug (NSAID) with a benzodiazepine (306 participants); two combined amitriptyline with fluoxetine (89 participants); two combined amitriptyline with a different agent (92 participants); two combined melatonin with an antidepressant (164 participants); one combined carisoprodol, paracetamol (acetaminophen), and caffeine (58 participants); one combined tramadol and paracetamol (acetaminophen) (315 participants); one combined malic acid and magnesium (24 participants); one combined a monoamine oxidase inhibitor with 5-hydroxytryptophan (200 participants); and one combined pregabalin with duloxetine (41 participants). Six studies compared the combination of multiple agents with each component alone and with inactive placebo; three studies compared combination pharmacotherapy with each individual component but did not include an inactive placebo group; two studies compared the combination of two agents with only one of the agents alone; and three studies compared the combination of two or more agents only with inactive placebo.Heterogeneity among studies in terms of class of agents evaluated, specific combinations used, outcomes reported, and doses given prevented any meta-analysis. None of the combinations of drugs found provided sufficient data for analysis compared with placebo or other comparators for our preferred outcomes. We therefore provide a narrative description of results. There was no or inadequate evidence in any comparison for primary and secondary outcomes. Two studies only reported any primary outcomes of interest (patient-reported pain relief of 30%, or 50%, or greater). For each 'Risk of bias' item, only half or fewer of studies had unequivocal low risk of bias. Small size and selective reporting were common as high risk of bias.Our GRADE assessment was therefore very low for primary outcomes of pain relief of 30% or 50% or greater, PGIC much or very much improved or very much improved, any pain-related outcome, participants experiencing any adverse event, any serious adverse event, or withdrawing because of an adverse event.Three studies found some evidence that combination pharmacotherapy reduced pain compared to monotherapy; these trials tested three different combinations: melatonin and amitriptyline, fluoxetine and amitriptyline, and pregabalin and duloxetine. Adverse events experienced by participants were not serious, and where they were reported (in 12 out of 16 studies), all participants experienced them, regardless of treatment. Common adverse events were nausea, dizziness, somnolence, and headache.

AUTHORS' CONCLUSIONS

There are few, large, high-quality trials comparing combination pharmacotherapy with monotherapy for fibromyalgia, consequently limiting evidence to support or refute the use of combination pharmacotherapy for fibromyalgia.

What Is Not in the Name? Dopa-Responsive Dystonia May Respond to More Than L-Dopa

BACKGROUND

Classic L-dopa-responsive dystonia is characterized by the triad of dystonia, diurnal fluctuation of signs, and dramatic response of signs to low-dose L-dopa therapy. Dopa-responsive dystonia succinctly summarizes the relevant clinical features. However, literal application of this label or consideration of dopa-responsive dystonia as a diagnostic end without molecular and/or biochemical definition may contribute to misdiagnosis and incomplete treatment in dopa-responsive conditions that impair synthesis of monoamine neurotransmitters besides dopamine.

PATIENT DESCRIPTION

We describe and provide video for twin patients with a rare form of dopa-responsive dystonia due to sepiapterin reductase deficiency. As is typical in dopa-responsive dystonia, these patients displayed dramatic improvement with L-dopa/carbidopa therapy. However, treatment was suboptimal until 5-hydroxytryptophan was added to address their serotonergic deficit.

DISCUSSION

Our report highlights the limitations of the dopa-responsive dystonia label and increases awareness of sepiapterin reductase deficiency and other conditions that may present as dopa-responsive dystonia. We provide a diagnostic and therapeutic approach to guide the clinician in evaluating and treating individuals with dopa-responsive dystonia.

Diagnosis, treatment and follow-up of patients with tetrahydrobiopterin deficiency in Shandong province, China

OBJECTIVES

To summarize the clinical and biochemical data, mutation analysis, treatment, outcome and the follow-up data of patients with BH4 deficiency from 2004 to 2012 in Shandong province, China.

METHODS

We analyzed the clinical, biochemical and treatment data of 40 patients with BH4 deficiency. Urinary neopterin and biopterin were analyzed. Further BH4 loading tests were performed in suspected patients with abnormal urinary pterin profiles. The patients with BH4 deficiency were treated with BH4 and neurotransmitter after diagnosis. Blood phenylalanine level, clinical symptoms and mental development were followed up.

RESULTS

40 cases with BH4 deficiency were identified and all classified as PTPS deficiency between 2004 and 2012 in Shandong province, China. They were diagnosed at the age of 20d - 41m and most patients received treatment with BH4, l-dopa and 5-HTP after diagnosis. Seven different mutations (P87S, K91R, T106M, D96N, N52S, S21R, and L127F) were detected in 11 patients. But outcome assessments were not always available. We obtained 19 records of DQ/IQ assessment. In 9 patients (7 early and 2 late diagnosed) no development delay is observed, while in 10 patients (8 early and 2 late diagnosed) development was delayed.

CONCLUSIONS

Our study emphasized that screening for BH4 deficiency should be carried out in all patients with HPA in order to minimize misdiagnosis. Although the outcomes of BH4 deficiency are highly variable, early diagnosis and treatment is essential for good outcomes.

The Successful Treatment of Opioid Withdrawal-Induced Refractory Muscle Spasms with 5-HTP in a Patient Intolerant to Clonidine

Instituting drug holidays for chronic opioid using patients is becoming commonplace for pain practitioners initiating procedures such as intrathecal pump or spinal cord stimulator trials. As such, pain practitioners need to be adept in their management of acute opioid withdrawal. Successfully weaning an opioid dependent patient off of chronic opioids requires a thorough knowledge of the available adjuvants to assist in this process. However, that selection can become exhausted by adjuvant side effects or by ineffective attenuation of opioid withdrawal symptoms. In that case, novel drugs, or novel application of currently available medications must be sought after to assist in the drug holiday. We present a case in which refractory muscle spasms secondary to opioid withdrawal were successfully treated with an over-the-counter supplement that is not typically used for the attenuation of opioid withdrawal symptoms. In a patient intolerant to the side effects of clonidine, we were able to successfully wean chronic opiates by treating refractory muscle spasms with the serotonin precursor, 5-hydroxytryptophan (5-HTP). We hypothesize that our success with this medication gives further credence to the role of serotonin in opioid withdrawal somatic symptomatology, and supports the need for future research to clarify the role of serotonin precursors or serotonin modulating drugs as potential alternatives in those unable to follow standard treatment protocols.

Sex, migraine and serotonin interrelationships

Sexual deficiency or frank impotence in man could be due to an imbalance of monoamines, particularly 5-HT, at the mating center level. An absolute or relative excess of 5-HT seems to antagonize testosterone at the level of the mating center receptors in the brain. Plasma testosterone levels in so-called psychological impotence are normal. When the 5-HT concentration in sexually deficient men is sufficiently decreased with parachlorophenylalanine (PCPA) treatment and testosterone levels increased following its administration, a vivid sexual stimulation appears in about half of the untractable cases. Similar results are observed by substituting testosterone with monoamine oxydase inhibitor (MAOI) in PCPA-treated volunteers. Furthermore, MAOI-PCPA are administered to emphasize the brain shift between serotonin and catecholamines. Yet the PCPA-MAOI treatment avoids the prostate carcinogenic risk of testosterone administration in aging males, and seems to have euphorizing effects stronger than those expected only from MAOI therapy. Because of the several side effects of PCPA-MAOI testosterone, the present experiments should be interpreted very cautiously.

Effect of L-5HTP and drugs acting on serotonin metabolism in various myoclonic syndromes

Ten patients affected by various myoclonic syndromes were tested with drugs acting on cerebral serotonin metabolism and with clonazepam (CZP). After L5HTP or serotonergic drugs administration a clear cut improvement was observed in the 2 patients affected by Ramsay-Hunt syndrome, while the patients with myoclonic epilepsy have shown no effect (3 cases) or negative response (1 case). Methysergide was active only in 1 patient affected by progressive erratic myoclonus who had a striking worsening of clinical picture. The main side effects observed were: gastrointestinal distress (L5HTP--4 patients, fenfluoramine--2, quipazine--1, methysergide--2) and cutaneous rash (quipazine--1 case). These results support the possible implication of the serotonergic system in the pathogenesis of myoclonus other than post-anoxic.

Clinical depression: an evidence-based integrative complementary medicine treatment model

BACKGROUND

Clinical depression has a major impact on individuals and society, often presenting the clinician with a significant challenge. Recent evidence suggests that synthetic antidepressants- although effective in the treatment of severe depressed mood-may have only a weak effect against mild-moderate forms of depression. In such cases, nonpharmaceutical options may be indicated. Furthermore, research findings suggest that select natural products are effective adjuvants when combined with synthetic antidepressants. Research concerning the treatment of depression emphasizes individual monotherapies, which is often incongruent with clinical reality. In practice, clinicians often use a variety of interventions; however, this approach may not be systematic, and many interventions used may not be based on strong evidence.

PRIMARY OBJECTIVE

This article proposes an evidence-based prescriptive clinical model based on the biopsychosocial model to treat unipolar depression. The "Antidepressant-Lifestyle- Psychological-Social (ALPS) depression treatment model" integrates nonpharmacological interventions (such as complementary medicines, lifestyle advice, and psychosocial techniques) for use by clinicians.

RESULTS

Initially a review of nonpharmacological mood-elevating interventions was undertaken. Evidentiary support was revealed for use of psychological techniques such as cognitive and behavioral medicine and interpersonal therapy, St John's wort, S-adenosyl methionine, and aerobic and anaerobic exercise. There were inconsistent research findings for acupuncture, omega-3 fish oils, and L-tryptophan for depressed mood. From these evidencebased interventions an integrative model was formed. Clinical recommendations in addition to a practical stepped-care decision tree are outlined.

CONCLUSION

The ALPS model has the potential to improve treatment outcomes and reduce relapse rates in clinical depression and warrants research using rigorous and appropriate methodology.

GTP-cyclohydrolase deficiency responsive to sapropterin and 5-HTP supplementation: relief of treatment-refractory depression and suicidal behaviour

The authors describe a new variant of guanosine triphosphate (GTP)- cyclohydrolase deficiency in a young man with severe and disabling major depressive disorder with multiple near-lethal suicide attempts. His cerebrospinal fluid levels showed that the concentration of tetrahydrobiopterin (BH4), neopterin, 5-hydroxyindoleacetic acid and homovanillic acid were below the reference range, suggesting a defect in the pterin biosynthetic pathway and in synthesis of dopamine and serotonin indicative of GTP-cyclohydrolase deficiency. Patient was started on sapropterin, a BH4 replacement protein, for the defect in the above pathway. In addition, the authors started 5-hydroxytryptophan titrated to 400 mg orally twice daily with concomittant carbidopa 37.5 mg orally four times a day, and he responded with remission of suicidal ideation and significant improvement in depression and function.

Nutraceuticals in the treatment of obsessive compulsive disorder (OCD): a review of mechanistic and clinical evidence

Obsessive-compulsive disorder (OCD) is a debilitating mental illness which has a significant impact on quality of life. First-line SSRI treatments for OCD typically are of limited benefit to only 40-60% of patients, and are associated with a range of adverse side effects. Current preclinical research investigating nutraceuticals (natural products) for OCD, reveals encouraging novel activity in modulating key pathways suggested to be involved in the pathogenesis of OCD (glutamatergic and serotonergic pathway dysregulation). Emerging clinical evidence also appears to tentatively support certain nutrients and plant-based interventions with known active constituents which modulate these pathways: N-acetlycysteine, myo-inositol, glycine, and milk thistle (Silybum marianum). The serotonin precursor tryptophan is unlikely to be of use in treating OCD while 5-HTP may possibly be a more effective precursor strategy. However, there is currently no clinical evidence to test the efficacy of either of these substances. Currently the balance of clinical evidence does not support the use of St. John's wort (Hypericum perforatum) in OCD. While clinical research in this area is in its infancy, further research into nutraceuticals is warranted in light of the promising preclinical data regarding their mechanisms of action and their favourable side effect profiles in comparison to current SSRI treatments. It is recommended that future clinical trials of nutraceutical treatments for OCD utilize randomized placebo-controlled study designs and considerably larger sample sizes in order to properly test for efficacy.

Autism associated with low 5-hydroxyindolacetic acid in CSF and the heterozygous SLC6A4 gene Gly56Ala plus 5-HTTLPR L/L promoter variants

The known Gly56Ala mutation in the serotonin transporter SERT (or 5-HTT), encoded by the SLC6A4 gene, causes increased serotonin reuptake and has been associated with autism and rigid-compulsive behavior. We report a patient with macrocephaly from birth, followed by hypotonia, developmental delay, ataxia and a diagnosis of atypical autism (PDD-NOS) in retrospect at the age of 4½years. Low levels of the serotonin end-metabolite 5-hydroxyindolacetic acid (5HIAA) in CSF were detected, and SLC6A4 gene analysis revealed the heterozygous Gly56Ala alteration and the homozygous 5-HTTLPR L/L promoter variant. These changes are reported to be responsible for elevated SERT activity and expression, suggesting that these alterations were responsible in our patient for low serotonin turnover in the central nervous system (CNS). Daily treatment with 5-hydroxytryptophan (and carbidopa) led to clinical improvement and normalization of 5HIAA, implying that brain serotonin turnover normalized. We speculate that the mutated 56Ala SERT transporter with elevated expression and basal activity for serotonin re-uptake is accompanied with serotonin accumulation within pre-synaptic axons and their vesicles in the CNS, resulting in a steady-state of lowered serotonin turnover and degradation by monoamine-oxidase (MAO) enzymes in pre-synaptic or neighboring cells.

Sepiapterin reductase deficiency in a 2-year-old girl with incomplete response to treatment during short-term follow-up

Sepiapterin reductase (SR) catalyses the last step in the tetrahydrobiopterin biosynthesis pathway; it converts 6-pyruvoyl-tetrahydropterin (6-PTP) to BH(4) in an NADPH-dependent reaction. SR deficiency is a very rare autosomal recessive disorder with normal phenylalanine (Phe) concentration in blood and diagnostic abnormalities are detected in CSF. We present a 16-month-old girl with SR deficiency. From the newborn period she presented with an adaptation regulatory disorder. At the age of 3 months, abnormal eye movements with dystonic signs and at 4.5 months psychomotor retardation were noticed. Since that time axial hypotonia with limb spasticity (or rather delayed reflex development), gastro-oesophageal reflux and fatigue at the end of the day has been observed. Brain MRI was normal; EEG was without epileptiform discharges. Analysis of biogenic amine metabolites in CSF at the age of 16 months showed very low HVA and 5-HIAA concentrations. Analysis of CSF pterins revealed strongly elevated dihydrobiopterin (BH(2)), slightly elevated neopterin and elevated sepiapterin levels. Plasma and CSF amino acids concentrations were normal. A phenylalanine loading test showed increased Phe after 1 h, 2 h and 4 h and very high Phe/Tyr ratios. SR deficiency was confirmed in fibroblasts and a novel homozygous g.1330C>G (p.N127K) SPR mutation was identified. On L-dopa and then additionally 5-hydroxytryptophan, the girl showed slow but remarkable progress in motor and intellectual ability. Now, at the age of 3 years, she is able to sit; expressive speech is delayed (to 1 1/2 years), passive speech is well developed. Her visual-motor skills, eye-hand coordination and social development correspond to the age of 2 1/2 years.

Formulations of dietary supplements and herbal extracts for relaxation and anxiolytic action: Relarian

Dietary supplements are widely used for desired effects on memory, insomnia, mood and anxiety. This review focuses on supplements which have anxiolytic or mild relaxation properties and enhance mood. For example, Kava (Piper methysticum) is reported to have anaxiolytic actions and to reduce tension through skeletal muscle relaxation. Dried passion flower (genus Passiflora) is reported to reduce insomnia and hysteria. Skullcap (genus Scutellaria), hops (Humulus lupulus), lemon balm (Melissa officinalis) and Valerian (Valeriana officinalis) root are all herbs reported as anaxiolytic calming agents. Further, extracts of Magnolia and Phellondendron bark are mild sedatives. Supplements such as gamma-aminobutyric acid (GABA), theanine, tryptophan and 5-hydroxytryptophan (5-HTP) are reported to promote relaxation. In general, these supplements appear to act as GABA receptor agonists or to boost GABA levels, although Kava inhibits both norephinephrine uptake and sodium and potassium channels and 5-HTP may act through elevation of serotonin. While questions remain in the literature regarding the medicinal value of these supplements in treating mood and anxiety disorders, based on cellular and animal studies as well as human clinical trials the literature supports a role for these preparations as useful alternatives in the management of the stress and anxiety of everyday life.

5-HT precursor loading, but not 5-HT receptor agonists, increases motor function after spinal cord contusion in adult rats

Serotonergic (5-HT) receptors are upregulated following spinal cord transection. Stimulation by administration of serotonergic receptor agonists has been successful in improving hindlimb function. We tested whether this strategy would be successful in incomplete injury models (moderate or severe thoracic contusion) where descending projections are partially spared which should produce less denervation-induced receptor upregulation. Adult rats received midthoracic moderate (MOD: 25 mm drop) or severe (SEV: 50 mm drop) contusion injuries. Distribution of 5-HT and its transporter and expression of 5-HT(2C) receptors were evaluated in lumbar spinal cord and motor response to 5-HT receptor activation was assessed using open field locomotion (BBB) score, percent weight supported treadmill stepping (%WS) and evaluation of hindlimb muscle activation (tremor and serotonin syndrome). 5-HT immunostaining 3 months post-contusion revealed few 5-HT fibers caudal to the severe contusion, and more spared caudal to the moderate contusion. The distribution of 5-HT transporter paralleled 5-HT staining, but was more greatly reduced. Thus serotonin reuptake may be less efficient in the injured spinal cord. Immunostaining for the 5-HT(2C) receptor in the dorsal and ventral horns at L5 showed significant upregulation in SEV, compared to sham or MOD rats. Neither 5-HT(2C) nor 5-HT(1A) receptor agonists, alone or in combination, nor the serotonin transporter inhibitor d-fenfluramine modified BBB scores or %WS in either group. Despite the increased sensitivity of post-synaptic targets, agonist treatment did not improve function in SEV rats. We conclude that selective 5-HT(2C) or 5-HT(1A) receptor activation was not effective in improving hindlimb function after incomplete lesions. In contrast, the 5-HT precursor 5-hydroxytryptophan (L-5-HTP), which leads to activation of all classes of 5-HT receptors, increased both %WS and hindlimb activity in the MOD group. While no side effects were observed in normal or MOD rats, SEV rats displayed hindlimb tremors and 33% mortality, indicating hypersensitivity to the precursor.

How physician obesity specialists use drugs to treat obesity

Specialist physicians may have prescribing habits that are different from nonspecialist physicians. Little is known about the prescribing habits of physicians specializing in the treatment of obesity. An anonymous survey was given to the physician members of the American Society of Bariatric Physicians (ASBP). There was a 35% response rate (266 physicians) to the questionnaire that was represented nationally. Almost all prescribed medications and all of them recommended phentermine. The average maximal dose of phentermine was above that approved in the package insert, and these physicians disagreed with the National Institutes of Health (NIH) Obesity Treatment Guidelines. Phendimetrazine, metformin, and phentermine plus L-5-hydroxytryptophan (5-HTP) with carbidopa were all used more frequently than either orlistat or sibutramine. The combination of sibutramine and orlistat as well as 5-HTP/carbidopa were prescribed by 14 and 20%, respectively. As 5-HTP-carbidopa was a combination not previously reported for the treatment of obesity, a retrospective chart review was performed in a single obesity practice, which may not be representative. Twenty-two subjects had a 16% weight loss with phentermine over 6 months and an additional 1% weight loss with the addition of 5-HTP/carbidopa for an additional 6 months. One subject who started on 5-HTP/carbidopa alone lost 24.4% of initial body weight over 6 months. This questionnaire revealed that 20% of the obesity specialists responding to the survey used phentermine plus of 5-HTP/carbidopa, an unreported combination. A controlled, randomized, clinical trial to evaluate the safety and efficacy of this combination in treating obesity should be considered.

[Myoclonic spasms: their clinical and neurophysiological characteristics, aetiology and treatment]

INTRODUCTION

Myoclonus refers to the brief, sudden, involuntary movements like jerks or twitches which produce a sudden muscular contraction.

AIMS

To review the clinical and neurophysiological features of myoclonus, or myoclonic spasms, and to carry out an updated examination of their causation and treatment.

DEVELOPMENT

Myoclonic spasms can be classified on the basis of different criteria. According to the underlying physiological mechanism, myoclonic spasms can be classified as cortical, subcortical, spinal or peripheral. Myoclonic spasms appear in a wide range of neurological diseases. So-called symptomatic myoclonus is the type that occurs secondary to an identifiable disorder; it is usually accompanied by other neurological signs and is the most frequent kind. Epileptic myoclonus is that which forms part of an epileptic syndrome with a genetic or idiopathic cause, or that is due to static encephalopathy. Essential myoclonus is the least frequent type and includes palatal myoclonus and dystonia-myoclonus syndrome. The main therapeutic objective consists in treating the underlying cause of the myoclonus if possible and in using symptomatic treatment when this is not the case. Antiepileptic drugs that enhance the effect of gamma-aminobutyric acid are still the most effective medication. Among the non-antiepileptic drugs, piracetam and 5-hydroxytryptophan stand out above the rest. Botulinum toxin has proved to be effective in palatal myoclonus. In dystonia-myoclonus syndrome, research has been conducted on the effectiveness of deep brain stimulation on the internal globus pallidus. In the most severe forms of myoclonus, monotherapy is not usually effective.

CONCLUSIONS

Progress has been made in furthering our knowledge of the neurophysiology of myoclonus, although no very effective forms of treatment have been reported for this motor disorder, which can be extremely disabling.

Genetic heterogeneity at the locus for hypoxanthine-guanine phosphoribosyltransferase

The purine phosphoribosyltransferases have emerged as important enzymes in the metabolic economy of the developing human. Hypoxanthine-guanine phosphoribosyltransferase (HGPRT, EC 2.4.2.8) catalyses the conversion of hypoxanthine and guinine into their respective nucleotides. Inherited variation in HGPRT first became evident through clinical observations with the definition of the Lesch-Nyhan syndrome. In this disorder, HGPRT activity in erythrocytes is almost zero, although the fact that sensitive electrophoretic analysis reveals a tiny amount of activity suggests that a protein of altered structure is present. Furthermore, this variant enzyme has been activated by manipulation in the presence of small amounts of normal enzyme. Nevertheless, no cross-reacting material could be detected in lysates of red cells or fibroblasts of patients with the syndrome when tested with antiserum prepared in rabbits to normal erythrocyte HGPRT. We have tested for the presence of cross-reacting material in 18 patients, and all were negative. More HGPRT variants are coming to light. Most of the patients have renal stone disease or gout but no other feature of the Lesch-Nyhan syndrome. In one family four affected males displayed about 5% of normal activity, and the enzyme migrated electrophoretically more rapidly than normal. Cross-reacting material could not be demonstrated in erythrocyte lysates, although it was clear that a variant protein was present. A boy with renal stone disease has been found to have about 1% of normal erythrocyte activity of HGPRT. Cross-reacting material was found in his erythrocytes. The data indicate that mutations which produce diminished enzyme activity in this protein with a distinct subunit structure may or may not so alter the tertiary state of the protein that immunoreactive sites are no longer available to antibody prepared against the normal enzyme. So far whenever a variant normal HGPRT has been found there has been an identifiable clinical illness. The different forms of illness provide for correlation of molecular structure and function in man.

Dihydropteridine reductase deficiency: Levodopa's long-term effectiveness without dyskinesia

We report an adult patient lacking endogenous synthesis of monoamines (dopamine, serotonin, and catecholamines) due to a severe dihydropteridine reductase (DHPR) deficiency. With levodopa and 5-hydroxytryptophan (5HTP) supplementation, the patient exhibited moderate mental retardation, acute episodes of parkinsonism, and episodes of depression. Despite the use of levodopa from age 3 months, he exhibited no dyskinesia or dopaminergic cell loss as suggested by normal PET imaging of the dopamine transporter.

[Study on tetrahydrobiopterin deficiency in Northern Chinese population]

OBJECTIVE

To emphasize early differential diagnosis from patients with hyperphenylalaninemia (HPA) and to evaluate the treatment and long-term outcome of patients with tetrahydrobiopterin synthase (BH4) deficiency in Northern Chinese population.

METHODS

From 1992 to 2005, a total of 618 patients with HPA were diagnosed and/or cared for in our outpatient clinic. Urinary pterin analysis, detection of dihydropteridine reductase (DHPR) activity in blood, and then BH4 loading tests were carried out to differentiate BH4 deficiency in these patients from classical phenylketonuria. BH4 deficient patients were treated with BH4, levodopa and 5-hydroxytryptophane (5-HTP) immediately while the diagnosis was done to disease. Patientso blood phenylalanine levels, psychomotor and intelligence development were followed up.

RESULTS

A total of 38 cases were diagnosed as BH4 deficiency, all of them were revealed as 6-pyruvoyl-tetrahydropterin synthase (PTPS) deficiency from the extremely decreased urine biopterin, normal DHPR activities and drop down of blood phenylalanine level to normal range within 4 to 8 hours after BH4 loading. The most common manifestations were progressively psychomotor and mental retardation to patients even after taking early dietary treatment. The patients were diagnosed and treated with drugs at the ages of 2.1 months to 13 years. With 4 patients died of pneumonia, 7 patients refused to treatment, only 27 patients were under treatment and followed up. The average full scale development or intelligence quotient (DQ/IQ) of patients who were treated within and after 6 months were 86+/- 10 or 66+/- 7 respectively. Development was not even in different aspects. A significant negative correlation was observed between the level of the DQ and the age of treatment commenced (r was -0.714, P< 0.01). Eleven patients experienced the extrapyramidal movement disorders, 3 of them combined with epilepsy. The extrapyramidal disorders were controlled by administration of levodopa.

CONCLUSION

The differential diagnosis for BH4 deficiency should be carried out in all patients with HPA. PTPS deficiency is the most common form of BH4 deficiency in Northern Chinese population. The long-term outcome of these patients benefits from diagnosis and treatment with BH4, levodopa and 5-HTP as early as possible.

Long-term follow-up of Chinese patients who received delayed treatment for 6-pyruvoyl-tetrahydropterin synthase deficiency

OBJECTIVES

6-Pyruvoyl-tetrahydropterin synthase (PTPS) deficiency is the most important type of BH4 deficiency related to hyperphenylalaninemia. PTPS deficiency may not only cause a typical phenylketonuric phenotype, but is also accompanied by various neurological signs and symptoms due to impaired synthesis of catecholamines and serotonin. Reports of the long-term outcomes of these patients, especially after delayed onset of therapy, are few.

STUDY DESIGN

We reviewed the characteristics of 10 PTPS-deficient patients whose treatment onset with tetrahydrobiopterin, L-DOPA, and hydroxytryptophan had been delayed. The relationships among clinical manifestations, biochemical findings, genotypes, and long-term outcomes were analyzed.

RESULTS

We classified eight patients as having severe forms, and two as having moderate forms of PTPS deficiency. Improvements in neurological status and intelligence/developmental quotient (IQ/DQ) were observed in all patients, up to approximately 15 years of follow-up. One patient began walking and talking after 4 years of treatment. In patients with severe disease, the mean initial IQ/DQ was 45.40 +/- 13.94, and the final full-scale intelligence quotient (FIQ) score was 62.8 +/- 13.06 (p = 0.042), with a mean increment of 17.4 +/- 5.27 over 15.86 +/- 4.85 years of follow-up. Two patients with moderately severe disease had FIQ increases from 75 to 77 and from 76 to 80 points, respectively.

CONCLUSIONS

The administration of neurotransmitters based on clinical response and adverse effects was beneficial in patients whose treatment of PTPS deficiency was delayed. Sustained clinical improvements were observed up to 15 years of follow-up.

Alterations in alcohol consumption, withdrawal seizures, and monoamine transmission in rats treated with phentermine and 5-hydroxy-L-tryptophan

We have previously shown that coadministration of the dopamine (DA) agonist phentermine plus the serotonergic agonist fenfluramine suppresses alcohol intake and withdrawal seizures in rats. In the present study, phentermine and the serotonin (5-HT) precursor, 5-hydroxy-L-tryptophan (5-HTP), were administered alone, or in combination, to rats fed on a 6% alcohol-containing diet or an isocaloric control diet. Following a 9-h withdrawal period from the alcohol-containing diet, phentermine enhanced the effects of 5-HTP on both reduction of alcohol withdrawal seizures as well as changes in striatal serotonin. Food intake was monitored for 24 h after drug treatment, and neurochemical measures were examined at various time points. Phentermine alone reduced food intake in all diet conditions, but this anorectic effect was followed by hyperphagia in control rats. Phentermine plus 5-HTP reduced the consumption of the alcohol-containing diet, while its effects on consumption of control diets were mixed. In vivo microdialysis in rat nucleus accumbens revealed that phentermine increased extracellular DA, whereas 5-HTP caused marked elevations in extracellular 5-HT. Coadministration of phentermine and 5-HTP evoked simultaneous elevations in extracellular DA and 5-HT that mirrored the effects of each drug alone. Collectively, these findings show that coadministered phentermine plus 5-HTP is effective in reducing alcohol intake and suppressing alcohol withdrawal seizures. These therapeutic actions may be related to elevations in synaptic DA and 5-HT in critical brain regions.

The potential of 5-hydryoxytryptophan for hot flash reduction: a hypothesis

Hormone replacement therapy (HRT) is contraindicated in women with a history of breast cancer or a high risk of breast cancer development. Recent results from large clinical trials, such as the Women's Health Initiative, have demonstrated increased risks of thromboembolic events and a moderate increased risk of breast cancer in women using conjugated estrogens and progestogens. There is a need for viable non-hormonal alternative treatments to HRT, such as nutritional and botanical therapies, in this population of women, who tend to experience more significant vasomotor symptoms. Safe and effective therapies that do not stimulate breast cell proliferation could prove extremely useful for the management of such symptoms for women in both low- and high-risk breast cancer populations. As a non-hormonal treatment, anti-depressants, such as selective serotonin reuptake inhibitors (SSRIs), have been shown to improve hot flash symptoms in women. The proposed mechanism is related to an increase in serotonin allowing for an increase in the set point of the brain's thermoregulator. In small clinical studies, the administration of tryptophan and 5-hydroxytryptophan (5HTP), the precursors of serotonin, have been shown to reduce depressive symptoms, possibly by enhancing the synthesis of serotonin. Thus, increased serotonin levels may have the ability to decrease hot flashes in a mechanism similar to that of SSRIs without the risks of breast cell stimulation. This would be particularly desirable for menopausal women with breast cancer or with risks of breast cancer. This article discusses the background information on hot flashes, SSRIs, tryptophan, and 5HTP, and possible clinical application of 5HTP for menopausal women with breast cancer risk.

Serotonin a la carte: supplementation with the serotonin precursor 5-hydroxytryptophan

This paper reviews the preclinical and clinical evidence regarding the use of the dietary supplement 5-hydroxytryptophan (5-HTP) for the treatment of depression. In the absence of supplementation with exogenous 5-HTP, the amount of endogenous 5-HTP available for serotonin synthesis depends on the availability of tryptophan and on the activity of various enzymes, especially tryptophan hydroxylase, indoleamine 2,3-dioxygenase, and tryptophan 2,3-dioxygenase (TDO). Factors affecting each of these are reviewed. The amount of 5-HTP reaching the central nervous system (CNS) is affected by the extent to which 5-HTP is converted to serotonin in the periphery. This conversion is controlled by the enzyme amino acid decarboxylase, which, in the periphery, can be blocked by peripheral decarboxylase inhibitors (PDIs) such as carbidopa. Preclinical and clinical evidence for the efficacy of 5-HTP for depression is reviewed, with emphasis on double-blind, placebo-controlled (DB-PC) trials. Safety issues with 5-HTP are also reviewed, with emphasis on eosinophilia myalgia syndrome (EMS) and serotonin syndrome.

6-pyruvoyl-tetrahydropterin synthase deficiency with mild hyperphenylalaninemia

Severe 6-pyruvoyl-tetrahydrobiopterin synthase deficiency is a tetrahydrobiopterin deficiency disorder that presents in infancy with developmental delay, seizures, and abnormal movements associated with hyperphenylalaninemia usually detectable by neonatal phenylketonuria screening programs. We describe an 8-year-old girl with delay, seizures, and dystonia with mild hyperphenylalaninemia detected in late childhood. The diagnosis of 6-pyruvoyl-tetrahydrobiopterin synthase deficiency was made by analysis of pterins in urine, pterins and neurotransmitters in cerebrospinal fluid, and enzyme assay. The patient improved clinically taking oral tetrahydrobiopterin, levodopa/carbidopa, and 5-hydroxytryptophan. This treatable condition may not always be detected by routine population screening for hyperphenylalaninemia.

Association between serotonin-related genetic polymorphisms and CCK-4-induced panic attacks with or without 5-hydroxytryptophan pretreatment in healthy volunteers

Genetic regulation of the function of serotonin (5-HT) may be important for the neurobiology of panic disorder. In order to evaluate the influence of 5-HT-related gene variants on the vulnerability to panic attacks, we genotyped 32 healthy volunteers who participated in the study of the effect of 5-hydroxytryptophan on panic attacks induced with cholecystokinin tetrapeptide (CCK-4). The polymorphisms of interest included those of 5-HT transporter (5-HTTLPR) and monoamine oxidase A (MAO-A promoter region) genes. The results showed significant associations between certain genotypes and panic rate in females but not in male volunteers. Specifically, there was a significantly lower rate of CCK-4-induced panic attacks in female subjects who had MAO-A longer alleles or 5-HTTLPR short allele gene variants. These data suggest that functional genetic polymorphisms of the 5-HT system may influence the vulnerability to panic attacks and add to the growing evidence of inhibitory function of 5-HT in the neuronal circuitry of panic.

5-Hydroxytryptophan plus SSRIs for interferon-induced depression: Synergistic mechanisms for normalizing synaptic serotonin

Interferon-alpha (IFN) is widely used in the treatment of certain cancers and viral infections, including hepatitis C (HCV). Unfortunately, depression is a common side effect of IFN therapy, affecting approximately a third of HCV patients receiving IFN therapy. Studies have shown that selective serotonin reuptake inhibitors (SSRIs) can effectively treat IFN-induced depression in only 63-75% of cases. For the remaining percentage, depression often necessitates dose reduction of or discontinuation from IFN therapy. Emerging evidence indicates that IFN may cause depression by affecting brain serotonin. IFN has been shown to increase serotonin reuptake and to decrease serotonin synthesis. We hypothesize that SSRIs are not fully effective because they affect only serotonin reuptake, not serotonin synthesis, and that effective treatment must address both uptake and synthesis. 5-Hydroxytryptophan (5-HTP) effectively increases central nervous system synthesis of serotonin. It is the immediate precursor of serotonin and is widely available as a dietary supplement, which is well absorbed after an oral dose. Several double-blind studies have shown 5-HTP to be effective in the treatment of nondrug-induced depression. We hypothesize that patients who become depressed on IFN will respond to the synergistic combination of SSRIs plus 5-HTP.

5-Hydroxy-L-tryptophan suppresses food intake in food-deprived and stressed rats

Giving L-tryptophan, serotonin's circulating precursor, or a serotonin-releasing drug can decrease food intake and body weight. Giving 5-hydroxy-L-tryptophan (5-HTP), serotonin's immediate intracellular precursor, has been thought to be ineffective in enhancing brain serotonin synthesis unless it is coadministered with a dopa decarboxylase inhibitor to protect 5-HTP from destruction outside the brain. We have examined the effect of 5-HTP on food consumption and tissue 5-HTP levels among rats subjected to two different hyperphagic stimuli, food deprivation and a standardized stress (tail pinch), and on plasma 5-HTP levels in humans. In rats, 5-HTP (3-200 mg/kg ip) suppressed food intake in a dose-dependent manner in both models, but was at least eight times more effective in our stress-hyperphagia model. (Differences in the two procedures might have contributed to the observed differences in potencies.) This suppression was blocked by coadministration of another large neutral amino acid (LNAA), L-valine. Brain 5-HTP levels correlated significantly with peak plasma 5-HTP (r(2)=.69) or 5-HTP/LNAA (r(2)=.81) levels. Additionally, among humans, oral 5-HTP (1.2-2.0 mg/kg) produced, after 1 and 2 h, a significant increase in plasma 5-HTP (1.5- to 2.3-fold). These observations suggest that 5-HTP may be useful in controlling the excessive food intake sometimes generated by stress, even if given without decarboxylase inhibitors or other drugs.

L -5-Hydroxytryptophan treatment of sleep terrors in children

To test the hypothesis that the administration of L -5-hydroxytryptophan (L -5-HTP) might exert beneficial effects on sleep terrors, we carried out an open pharmacological trial in a group of children with sleep terrors compared to a group of children with the same disorder but without L -5-HTP treatment. Participants in the trial were 45 children (34 males and 11 females; age range 3.2-10.6 years), referred to the Sleep Centre of the Department of Developmental Neurology and Psychiatry of the University of Rome "La Sapienza", affected by sleep terrors. All subjects underwent: (1) complete medical and sleep history; (2) complete neurological examination and EEG recording whilst awake and sleeping, (3) a structured sleep diary for 2 months, (4) after 1 month, all subjects were examined again from the clinical and EEG points of view and (5) after 6 months, a structured interview in order to evaluate the clinical outcome. After the first visit, L -5-HTP was administered (2 mg/kg per day) at bedtime to 31 randomly selected patients for a single period of 20 consecutive days. After 1 month of treatment, 29/31 (93.5%) of patients showed a positive response. In the comparison group without drug therapy, after 1 month, the episodes disappeared only in four children (28.6%) while ten children (71.4%) showed the persistence of episodes with the same frequency as before. After 6 months, 26/31 (83.9%) of children treated with L -5HTP were sleep terror-free, while in five children (16.1%) sleep terror episodes persisted. Of the children in the comparison group, ten (71.4%) continued to show sleep terrors at 6-month follow-up.

CONCLUSION

to our knowledge, this is the first study demonstrating the efficacy of a new drug treatment for sleep terrors. These results confirm our initial hypothesis and represent evidence that treatment with L -5-hydroxytryptophan is able to modulate the arousal level in children and to induce a long-term improvement of sleep terrors.

The effect of 5-hydroxytryptophan on cholecystokinin-4-induced panic attacks in healthy volunteers

Previous studies suggest a modulatory role of serotonin (5-HT) in experimentally-induced panic attacks. In the current study, we investigated the acute effects of 5-HT precursor l-5-hydroxytryptophan (5-HTP) on the response to panicogenic challenge with cholecystokinin-tetrapeptide (CCK-4) in healthy volunteers. Thirty-two subjects were randomized to receive either 200 mg of 5-HTP or placebo with the CCK-4 challenge following in 90 min in a double-blind, parallel-group design. The results showed a nonsignificant difference between the groups in panic rate (19% after 5-HTP and 44% after placebo, p = 0.13) with a trend for lower intensity of symptoms after 5-HTP (p = 0.08). Further analysis by gender revealed that females in the 5-HTP group had a significantly lower panic rate and intensity of cognitive symptoms whereas, in males, the effect of 5-HTP was limited to lowering the intensity of somatic panic symptoms. Thus, an increased availability of 5-HT may have a gender-dependent protective effect in CCK-4-induced panic.

Selected integrative medicine treatments for depression: considerations for women

This review evaluates the research published between 1966 and 2004 on several integrative treatments for depression, including omega-3 fatty acids, Hypericum perforatum (St. John's Wort), S-adenosyl-methionine, folate, 5-Hydroxytryptophan, acupuncture, exercise, and light therapy, with a particular emphasis on issues pertinent to women. Data from double-blind, placebo-controlled trials support each of these as treatment interventions for depression. We discuss both the strength of the evidence for each treatment and methodological issues related to interpretation of efficacy. Available data pertaining to considerations in women, including use during pregnancy and breastfeeding and interactions with hormonal therapies are discussed. The reviewed treatments deserve further research. Their appropriate place in the armamentarium of depression treatments for women must be defined. An evidence-based integrative medicine approach brings together treatment options with proven efficacy and the public's desire for complementary and alternative medicine treatments.

The serotonin precursor 5-hydroxytryptophan delays neuromuscular disease in murine familial amyotrophic lateral sclerosis

INTRODUCTION

Reduction in the levels of whole-blood serotonin is a common feature of Down syndrome (DS) individuals and transgenic mice overexpressing wild-type SOD1. Administration of the metabolic precursor 5-hydroxytryptophan (5-HTP) leads to reversal of both serotonin deficits and hypotonia in humans. The effect of 5-HTP treatment on the progression of motor neuron disease in mutant SOD1 mice was examined.

METHODS

Pre-disease transgenic SOD1 G93A mice and wild-type littermates were systemically administered 5-HTP thrice weekly (0, 5 or 50 mg/kg). Animal weights, locomotor function and survival were recorded weekly. Plasma serotonin levels were measured post-mortem.

RESULTS

Treatment with 5-HTP significantly delayed hindlimb weakness and mortality in SOD1 G93A mice in a dose-dependent manner. Wild-type mice were not adversely affected by 5-HTP administration. Baseline serotonin levels did not differ between wild-type and ALS mice. Blood platelet serotonin levels increased proportionally with dose.

CONCLUSIONS

Increased blood serotonin by administration of 5-HTP in SOD1 G93A mice led to improved locomotor function and survival. A role for serotonin metabolism in mice with elevated SOD1 expression and motor neuron disease is suggested by these studies.

Review of the implications of dietary tryptophan intake in patients with irritable bowel syndrome and psychiatric disorders

In this review, we address the possible role of the essential amino acid L-tryptophan or its metabolic derivative 5-hydroxytryptophan in the modulation of serotonin (5-hydroxytryptamine) synthesis and thereby in affecting the pathophysiology of central and peripheral nervous system disorders, including depression and irritable bowel syndrome. L-Tryptophan may represent a link between apparently disparate functional disorders and is of interest for general gastroenterologists, neurogastroenterologists, and neurologists. On the basis of estimates showing that approximately 20% of patients with functional bowel disorders seeking care in referral centres have psychiatric comorbidity, we attempt to provide a conceptual framework for defining the possible role of L-tryptophan in this population.

Increases in avoidance responding produced by REM sleep deprivation or serotonin depletion are reversed by administration of 5-hydroxytryptophan

Our objective was to directly compare the effects of rapid eye movement (REM) sleep deprivation (REMSD) and serotonin 5-hydroxytryptamine (5-HT) depletion on free-operant avoidance behavior in rats. These experiments were designed to determine if declining 5-HT levels observed during REMSD might mediate the increases in avoidance responding observed in REM sleep deprived rats. Rats were trained on a free-operant avoidance task. Following training, the animals were assigned to one of three sleep conditions (REMSD, tank control, or cage control). Animals in each sleep condition were exposed to four 5-HT manipulations: (a) saline plus saline; (b) p-chlorophenylalanine (PCPA) plus saline; (c) saline plus 5-hydroxytryptophan (5-HTP) and (d) PCPA plus 5-HTP. Both REMSD and 5-HT depletion via PCPA resulted in an increase in avoidance responding that was reversed by administration of 5-HTP. REMSD and 5-HT depletion via PCPA resulted in increased avoidance efficiency and were reversed by 5-HTP administration, but only changes following PCPA injection were statistically significant. Decreases in 5-HT levels that occur during REMSD likely mediate increases in avoidance responding.

Are tryptophan and 5-hydroxytryptophan effective treatments for depression? A meta-analysis

OBJECTIVE

To review the literature regarding the effectiveness of 5-hydroxytryptophan (5-HT) and L-tryptophan in the treatment of unipolar depression.

METHODS

A systematic review of the literature from 1966 to 2000 using the search terms 'tryptophan', 5-hydroxytryptophan', '5-HTP', '5-HT' and 'depression'. We extracted and grouped data for meta-analysis by pooling odds ratios (OR) and relative risks where possible.

RESULTS

One hundred and eight studies were located of which only two studies, one of 5-HT and one of L-tryptophan, with a total of 64 patients met sufficient quality criteria to be included. These studies suggest 5-HT and L-tryptophan are better than placebo at alleviating depression (Peto OR = 4.1, 95% CI = 1.3-13.2). However, the small size of the studies, and the large number of inadmissible, poorly executed studies, casts doubt on the result from potential publication bias, and suggests that they are insufficiently evaluated to assess their effectiveness.

CONCLUSION

A large body of evidence was subjected to very basic criteria for assessing reliability and validity, and was found to largely be of insufficient quality to inform clinical practice. More well-designed studies are urgently required to enable an assessment of what may be an effective class of agents.

Treatment and outcome of Taiwanese patients with 6-pyruvoyltetrahydropterin synthase gene mutations

Ten cases of tetrahydrobiopterin (BH4) deficiency were identified in 1,337,490 newborns screened in a Chinese population in Taiwan. The high incidence of BH4 deficiency in the Taiwanese population may be explained by a founder effect, since all of the patients revealed 6-pyruvoyltetrahydropterin synthase gene mutations, and grouping N52S and P87S mutations together constituted 88.9% of the disease alleles. BH4 supplementation with restriction of high-protein foods gave control of plasma phenylalanine within normal range, and levodopa itself prevented seizure. However, the average intelligence quotient (IQ) score of these patients was only 76 +/- 14 (56-98). Statistically, the age of starting medication, including 5-hydroxytryptophan (5-HTP), was inversely correlated to IQ scores of these patients. We suggest the combination of BH4, levodopa and 5-HTP as the standard protocol to commence the treatment of BH4 deficiency as early as possible, although prenatal brain damage could have existed.

Tetrahydrobiopterin-deficient hyperphenylalaninemia in the Chinese

BACKGROUND

Hyperphenylalaninemia (HPA) may be caused by either a deficiency in phenylalanine-4-hydroxylase or in tetrahydrobiopterin (BH4), the essential cofactor required for the hydroxylation of aromatic amino acids. The most common forms of BH4 deficiency are 6-pyruvoyl-tetrahydropterin synthase (PTPS) deficiency (MIM 261640) and dihydropteridine reductase (DHPR) deficiency (MIM 261630), which require a different treatment from classical HPA.

RESULTS

Approximately 86% of BH4-deficient HPA in the Chinese population was found to be caused by PTPS deficiency. Eleven missense (73C-->G, 120T-->G, 155A-->G, 166G-->A, 200C-->T, 209T-->A, 226C-->T, 259C-->T, 286G-->A, 317C-->T, 430G-->C), one splicing (IVS3+1G-->A) and two deletion mutations (116-119delTGTT, 169-171delGTG) were identified in 37 unrelated PTPS-deficient Chinese families. Among these, 155A-->G, 259C-->T and 286G-->A mutation accounted for about 80% of the mutant alleles. The 155A-->G and 286G-->A mutations were found to be the common mutation in southern and northern Chinese, respectively. Only two Chinese DHPR-deficient families were detected among about 300 Chinese hyperphenylalaninemia cases. A single base transition 508G-->A on the DHPR cDNA was identified in two consanguineous DHPR-deficient siblings. A reduced level of DHPR mRNA expression was found in the other DHPR-deficient patient, which suggested that the mutation might lie in the regulatory region of the DHPR gene.

CONCLUSIONS

The BH4-deficient HPA was estimated to make up around 30% of the Chinese population in Taiwan suffering from HPA, which is much higher than in Caucasian populations (1.5-2% of HPA).

A novel neurodevelopmental syndrome responsive to 5-hydroxytryptophan and carbidopa

Tryptophan hydroxylase (TPH; EC 1.14.16.4) catalyzes the first rate-limiting step of serotonin biosynthesis by converting l-tryptophan to 5-hydroxytryptophan. Serotonin controls multiple vegetative functions and modulates sensory and alpha-motor neurons at the spinal level. We report on five boys with floppiness in infancy followed by motor delay, development of a hypotonic-ataxic syndrome, learning disability, and short attention span. Cerebrospinal fluid (CSF) analysis showed a 51 to 65% reduction of the serotonin end-metabolite 5-hydroxyindoleacetic acid (5HIAA) compared to age-matched median values. In one out of five patients a low CSF 5-methyltetrahydrofolate (MTHF) was present probably due to the common C677T heterozygous mutation of the methylenetetrahydrofolate reductase (MTHFR) gene. Baseline 24-h urinary excretion showed diminished 5HIAA values, not changing after a single oral load with l-tryptophan (50-70 mg/kg), but normalizing after 5-hydroxytryptophan administration (1 mg/kg). Treatment with 5-hydroxytryptophan (4-6 mg/kg) and carbidopa (0.5-1.0 mg/kg) resulted in clinical amelioration and normalization of 5HIAA levels in CSF and urine. In the patient with additional MTHFR heterozygosity, a heterozygous missense mutation within exon 6 (G529A) of the TPH gene caused an exchange of valine by isoleucine at codon 177 (V177I). This has been interpreted as a rare DNA variant because the pedigree analysis did not provide any genotype-phenotype correlation. In the other four patients the TPH gene analysis was normal. In conclusion, this new neurodevelopmental syndrome responsive to treatment with 5-hydroxytryptophan and carbidopa might result from an overall reduced capacity of serotonin production due to a TPH gene regulatory defect, unknown factors inactivating the TPH enzyme, or selective loss of serotonergic neurons.

Biological correlations of suicide and aggressivity in major depressions (with melancholia): 5-hydroxyindoleacetic acid and cortisol in cerebral spinal fluid, dexamethasone suppression test and therapeutic response to 5-hydroxytryptophan

5-Hydroxyindoleacetic acid (5-HIAA) and cortisol in cerebrospinal fluid (CSF), response of the dexamethasone suppression test (DST) and the clinical response to treatment with 5-hydroxytryptophan (5-HTp) plus carbidopa were studied in a group of 21 depressed inpatients (major depression with melancholia) in order to correlate biological findings with psychopathologicalones. A positive correlation was found between strong suicidal thoughts, suicidal attempts and self-aggressivity and low concentration of 5-HIAA in CSF and a less significant but still positive correlation with abnormal DST response and with clinical response to the treatment.

Tryptophan and 5-hydroxytryptophan for depression

BACKGROUND

5 Hydroxytryptophan (5-HTP) and tryptophan are so-called natural alternatives to traditional antidepressants, used to treat unipolar depression and dysthymia.

OBJECTIVES

To determine whether 5-HTP and tryptophan are more effective than placebo, and whether they are safe to use to treat depressive disorders in adults.

SEARCH STRATEGY

Trials were searched in computerized general (Medline, Psychlit, and Embase) and specialized databases (Cochrane Controlled Clinical Trials Register, Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trial Register); by checking reference lists of relevant articles; by handsearching relevant specialist journals; and by contacting relevant authors where appropriate. Publications in all languages were sought.

SELECTION CRITERIA

Trials were included if they were randomized, included patients with unipolar depression or dysthymia, compared preparations of 5-HTP or tryptophan with placebo, and included clinical outcomes assessed by scales assessing depressive symptoms.

DATA COLLECTION AND ANALYSIS

Data was extracted independently by the three reviewers, onto data collection forms. Inclusion criteria were applied to all potential studies independently and a coefficient of agreement (Kappa) was calculated for them. Disagreement was resolved by reaching consensus. Trial quality was scored according to risk of bias. Analysis for 5-HTP and tryptophan were combined due to the small number of included trials.

MAIN RESULTS

108 trials were located using the specified search strategy. Of these, only two trials, involving a total of 64 patients, were of sufficient quality to meet inclusion criteria. The available evidence suggests these substances were better than placebo at alleviating depression (Peto Odds Ratio 4.10; 95% confidence interval 1.28-13.15; RD 0.36; NNT 2.78). However, the evidence was of insufficient quality to be conclusive.

REVIEWER'S CONCLUSIONS

A large number of studies appear to address the research questions, but few are of sufficient quality to be reliable. Available evidence does suggest these substances are better than placebo at alleviating depression. Further studies are needed to evaluate the efficacy and safety of 5-HTP and tryptophan before their widespread use can be recommended. The possible association between these substances and the potentially fatal Eosinophilia-Myalgia Syndrome has not been elucidated. Because alternative antidepressants exist which have been proven to be effective and safe the clinical usefulness of 5-HTP and tryptophan is limited at present.

L-5-Hydroxytryptophan in the prophylaxis of chronic tension-type headache: a double-blind, randomized, placebo-controlled study. For the Portuguese Head Society

A parallel, randomized, double-blind trial is reported, in which 78 patients with chronic tension-type headaches were treated with L-5-hydroxytryptophan (5-HTP) (n = 43) or placebo (n = 35) for 8 weeks, after a washout period of 2 weeks and with a follow-up period of a further 2 weeks. Five patients dropped out (1 with placebo and 4 with 5-HTP), 1 was excluded due to noncompliance, and in 7 treatment was suspended due to adverse events (3 with placebo and 4 with 5-HTP), yielding a final number for evaluation of 65 patients. In comparison with the group treated with placebo, there was no statistically significant change in the number of days with headache or in headache intensity in the group treated with 5-HTP, 300 mg per day; however, there was a significant decrease in the consumption of analgesics. During the 2 weeks after treatment, there was a significant decrease in the number of days with headache. Subjective opinion during this latter period was also favorable to 5-HTP.

L-5-hydroxytryptophan can prevent nociceptive disorders in man

Prevention of primary pain is a new topic, endowed with social and economic interest. We observed that L-5-HTP can induce a significant decrease of the cropping out of migraine, the commonest primary pain. This finding seems interesting, since it represents the first data in the field and was obtained in a prospective, long-term, placebo controlled study. The result obtained suggests that CNS abnormalities underlying the mechanism of migraine can be changed by L-5-HTP, if the amino acid is administered to subjects who are predisposed to headache.

Use of neurotransmitter precursors for treatment of depression

Insufficient activity of the neurotransmitters serotonin and norepinephrine is a central element of the model of depression most widely held by neurobiologists today. In the late 1970s and 1980s, numerous studies were performed in which depressed patients were treated with the serotonin precursors L-tryptophan and 5-hydroxytryptophan (5-HTP), and the dopamine and norepinephrine precursors tyrosine and L-phenylalanine. This article briefly reviews the published research on the efficacy of neurotransmitter precursors in treating depression, highlights the findings of studies, and discusses issues regarding the interpretation of those findings. The nature of the studies makes it difficult to draw firm conclusions regarding the efficacy of neurotransmitter precursors for treating depression. While there is evidence that precursor loading may be of therapeutic value, particularly for the serotonin precursors 5-HTP and tryptophan, more studies of suitable design and size might lead to more conclusive results. However, the evidence suggests neurotransmitter precursors can be helpful in patients with mild or moderate depression.

[Progressive convulsive encephalopathy: considering a abnormality of biopterin metabolism]

BACKGROUND

Symptomatic forms of hyperphenylalaninemia are rare in France since neonatal screening began.

CASE REPORT

A child born in Algeria from consanguinous parents was referred at 2 years of age for a severe epileptic encephalopathy with hypotonia. Amino acid chromatography revealed hyperphenylalaninemia due to a dihydropteridine reductase deficiency. Dietary restriction of phenylalanine and oral administration of amine precursors, L-dopa and 5-hydroxytryptophan had poor efficiency on epilepsy and psychomotor delay.

CONCLUSION

Diagnosis of hyperphenylalaninemia must be evoked in any children with progressive encephalopathy born in country where neonatal screening is not performed.

Fibromyalgia and the serotonin pathway

Fibromyalgia syndrome is a musculoskeletal pain and fatigue disorder manifested by diffuse myalgia, localized areas of tenderness, fatigue, lowered pain thresholds, and nonrestorative sleep. Evidence from multiple sources support the concept of decreased flux through the serotonin pathway in fibromyalgia patients. Serotonin substrate supplementation, via L-tryptophan or 5-hydroxytryptophan (5-HTP), has been shown to improve symptoms of depression, anxiety, insomnia and somatic pains in a variety of patient cohorts. Identification of low serum tryptophan and serotonin levels may be a simple way to identify persons who will respond well to this approach.

5-Hydroxytryptophan: a clinically-effective serotonin precursor

5-Hydroxytryptophan (5-HTP) is the intermediate metabolite of the essential amino acid L-tryptophan (LT) in the biosynthesis of serotonin. Intestinal absorption of 5-HTP does not require the presence of a transport molecule, and is not affected by the presence of other amino acids; therefore it may be taken with meals without reducing its effectiveness. Unlike LT, 5-HTP cannot be shunted into niacin or protein production. Therapeutic use of 5-HTP bypasses the conversion of LT into 5-HTP by the enzyme tryptophan hydroxylase, which is the rate-limiting step in the synthesis of serotonin. 5-HTP is well absorbed from an oral dose, with about 70 percent ending up in the bloodstream. It easily crosses the blood-brain barrier and effectively increases central nervous system (CNS) synthesis of serotonin. In the CNS, serotonin levels have been implicated in the regulation of sleep, depression, anxiety, aggression, appetite, temperature, sexual behaviour, and pain sensation. Therapeutic administration of 5-HTP has been shown to be effective in treating a wide variety of conditions, including depression, fibromyalgia, binge eating associated with obesity, chronic headaches, and insomnia.

L-5-hydroxytryptophan does not stimulate LH secretion directly from the pituitary in patients with gonadotrophin releasing hormone deficiency

OBJECTIVE

There is abundant histological and physiological evidence that serotonin plays a role in the regulation of LH secretion in rats. Studies in human subjects have been few, but their results include the finding that pulsatile administration of L-5-hydroxytryptophan (5-HTP, the immediate precursor of serotonin) amplifies LH secretion in women in the medium-late follicular phase, and that this effect is not due to 5-HTP directly inducing LH secretion by the pituitary. We have investigated whether 5-HTP amplifies LH secretion by enhancing the response of the pituitary to GnRH.

PATIENTS

Seven patients aged 20-40 years with hypogonadotrophic hypogonadism (HH) of hypothalamic origin (3 men with Kallmann's syndrome, 2 women without anosmia and with GH deficiency, and 2 women with anorexia nervosa).

DESIGN

To prime the pituitary, subcutaneous pulsatile GnRH was administered for 7 days at the rate of one 5-20 micrograms pulse every 90 min. The day before the investigation, this regimen was replaced by 1.5-3 micrograms intravenous pulses at the same frequency. On the day of the investigation, 3 ml blood samples were taken every 10 min from 0850 to 19:00 hours. After the first two samples, the intravenous GnRH pulse frequency was increased to one per hour and was maintained at this level throughout the rest of the study. The first 4 h of the study acted as a control phase allowing determination of the pituitary response to GnRH. At 1300 h, 75 mg of the aromatic-L-amino-acid decarboxylase inhibitor carbidopa was administered orally; carbidopa does not cross the blood-brain barrier, and prevents peripheral conversion of 5-HTP to serotonin. At 1600 h, another 75 mg dose of carbidopa was administered, and administration of 8-20 mg pulses of 5-HTP at a rate of one pulse per hour was begun.

MEASUREMENTS

LH was determined in triplicate by an immunoradiometric assay (IRMA), and LH pulses identified by means of a program developed in our laboratory.

RESULTS

When pulsatile administration of GnRH was accompanied by administration of carbidopa and 5-HTP, LH pulse amplitude (2.32 +/- 0.71 IU/I) did not differ significantly from its value in either the GnRH+ carbidopa phase (2.58 +/- 1.12 IU/I) or the unaccompanied GnRH phase (2.77 +/- 1.76 IU/I).

CONCLUSIONS

L-5-hydroxytryptophan-induced amplification of LH secretion in humans is not due to enhancement of the pituitary response to GnRH. The effect of L-5-hydroxytryptophan must therefore be due to its action on the hypothalamus, where it may be hypothesized that it increases GnRH release.