Effects of 5HTP on the Injured Human Spinal Cord
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: 5-Hydroxytryptophan 100 MG, 5-Hydroxytryptophan, Carbidopa, Placebo.
- Who it may be relevant to
- Registry conditions: Spinal Cord Injuries. Basic parameters: 18 years — 65 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- United States, Canada
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
Effects of the Serotonin Precursor, 5-hydroxytryptophan, in the Injured Human Spinal Cord
Overview
This study will assess how the serotonin precursor, 5-HTP, alter nervous system excitability and motor function in individuals with spinal cord injuries of differing chronicity and severity. Participants will visit the lab on 4 separate occasions where they will be administered four different drugs in a randomized, double-blinded, placebo-controlled crossover design.
Detailed description
This study will assess for the first time the effects of 5-HTP on neural excitability utilizing a combination of neurophysiological and functional testing in subacute motor complete (AIS A/B), chronic motor complete (AIS A/B) and chronic incomplete (AIS C/D) SCI participants. To reduce peripheral side effects such as nausea, these supplements will be co-administered with carbidopa which inhibits the action of peripheral AADC, thereby ensuring that 5-HTP can effectively cross the blood brain barrier prior to being broken down. The neurophysiological outcomes will allow for the determination of the mechanistic actions of each pharmacological agent on different pathways/sites within the central nervous system in three different patient populations with varying degrees of lesion severity and will for the determination of whether increased Amino Acid Decarboxylase (AADC) expression and therefore the efficacy of this approach is correlated to lesion severity and/or chronicity. Importantly, the use of functional testing will allow for the determination of whether these often-reported neurophysiological changes translate to improvements in muscle activation patterns and kinematics during cycling.
The effects of 5-HTP will be assessed across three different participant groups: i) subacute (6 months-1 year) AIS A/B SCI individuals, ii) chronic (\>2 years post injury) AIS A/B SCI individuals and iii) chronic AIS C/D SCI individuals.. In a placebo-controlled, randomized crossover design, participants will receive i) 50 mg 5HTP combined with 50 mg carbidopa, ii) 100 mg 5-HTP combined with 50 mg carbidopa, iii) 50 mg carbidopa only or iv) placebo. Ten participants will be recruited in each group. Participants will visit the lab on four separate occasions, separated by at least 72 hours.
Interventions
- Drug 5-Hydroxytryptophan 100 MG
100mg combined with 50mg carbidopa - Drug 5-Hydroxytryptophan
50mg combined with 50mg carbidopa - Drug Carbidopa
50mg - Drug Placebo
Placebo
Primary outcome measures
- Change in motoneuron excitability [Time frame: Pre drug-intake, 30minutes, 60minutes, 90minutes and 120minutes post drug-intake]
- Change in spinal excitability [Time frame: Pre drug-intake, 30minutes, 60minutes, 90minutes and 120minutes post drug-intake]
- Change in flexor reflex/spasms [Time frame: Pre drug-intake, 30minutes, 60minutes, 90minutes and 120minutes post drug-intake]
- Change in functional movement performance [Time frame: Pre drug-intake, 120-150minutes post drug-intake]
Secondary outcome measures (4)
- Serum analysis of 5HIAA (UofL Cohort only) [Time frame: 90-120minutes post drug-intake]
- Serum analysis of serotonin (UofL Cohort only) [Time frame: 90-120minutes post drug-intake]
- Serum analysis of cortisol (UofL Cohort only) [Time frame: 90-120minutes post drug-intake]
- Whole blood analysis of Serotonin (UofL Cohort only) [Time frame: 90-120minutes post drug-intake]
Eligibility criteria
Inclusion criteria
- participants must have suffered trauma to the spinal cord at least six months ago or longer
Exclusion criteria
- individuals with damage to the nervous system other than to the spinal cord
- pregnant and/or breastfeeding women
- alcoholic participants
- history of seizure/epilepsy
- history of suicidal thoughts or behaviors
- known or suspected allergy to the medication ingredients
- cardiovascular disease including history of heart attack or heart rhythm irregularities
- coronary artery disease
- reduced liver function or disease
- reduced kidney function or disease
- lung disease
- comatose or depressed states due to CNS depressants
- endocrine dysfunction
- blood dyscrasias or blood related disease
- bone marrow depression
- hypocalcemia
- history of stomach ulcers
- wide angle glaucoma
- phenylketonuria
- history of tumors
- uncontrolled heart problems
- unstable psychiatric or mental disorder
Participants taking:
- monoamine oxidase inhibitor therapy
- serotonergic antidepressants
- tricyclic antidepressants
- any type of serotonergic agonist
- dopamine D2 receptor antagonists
- amphetamine
- CNS depressants
- levodopa
- lithium
- anti-hypertensive drugs
- iron salts
- metoclopramide
- phenothiazine medication
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Allocation
- Randomized
- Model
- Crossover
- Masking
- Double blind
- Primary purpose
- Basic science
Study locations
United States · 1 center
- University of Louisville — Louisville
Canada · 1 center
- University of Alberta — Edmonton
Identifiers
NCT: NCT04520178 · Pro00119483/00125176