Effects of Alpha-lactalbumin Intake on Metabolic and Cognitive Functions in Elderly
| Status: | Active, not recruiting |
|---|---|
| Conditions: | Cognitive Studies |
| Therapuetic Areas: | Psychiatry / Psychology |
| Healthy: | No |
| Age Range: | 55 - Any |
| Updated: | 4/17/2018 |
| Start Date: | March 2014 |
| End Date: | February 2020 |
Effects of Alpha-lactalbumin on Metabolic and Cognitive Functions in Healthy Older Adults
Aging modifies the metabolic pathway of the neurotransmitter serotonin by reducing the
synthesis rate and increasing the breakdown rate of serotonin, possibly related to the
observed enhanced sensitivity of the serotonergic pathway. Since serotonin plays a prominent
role in neuropsychological functions such as anxiety, mood and memory, the enhanced
sensitivity of the serotonergic pathway in aging can probably explain the fact that elderly
are more vulnerable to develop cognitive deficits and depressive symptoms.
Serotonin synthesis in brain is regulated by its precursor tryptophan (TRP). Because
tryptophan is an essential amino acid, modifying the availability of tryptophan through
dietary intake, can directly influence central serotonin metabolism and consequently
affective and cognitive processes.
The aim of this study is to test the hypothesis that an acute intake of whey protein with
high levels of TRP such as alpha-lactalbumin can stabilize the metabolism of serotonin and
subsequently enhance metabolic and cognitive functions in healthy older adults. The acute
effects of this dietary protein will be investigated in subjects with mild cognitive
impairment (MCI), or dementia, compared to control subjects in order to examine whether
healthy older subject with MCI benefit more from the intake of alpha-lactalbumin and/or whey.
The investigators will investigate if this meal can optimize serotonin metabolism by
elevating plasma TRP levels and plasma TRP appearance and enhance splanchnic TRP extraction.
In addition, the effects on mood and cognitive functions will be examined.
synthesis rate and increasing the breakdown rate of serotonin, possibly related to the
observed enhanced sensitivity of the serotonergic pathway. Since serotonin plays a prominent
role in neuropsychological functions such as anxiety, mood and memory, the enhanced
sensitivity of the serotonergic pathway in aging can probably explain the fact that elderly
are more vulnerable to develop cognitive deficits and depressive symptoms.
Serotonin synthesis in brain is regulated by its precursor tryptophan (TRP). Because
tryptophan is an essential amino acid, modifying the availability of tryptophan through
dietary intake, can directly influence central serotonin metabolism and consequently
affective and cognitive processes.
The aim of this study is to test the hypothesis that an acute intake of whey protein with
high levels of TRP such as alpha-lactalbumin can stabilize the metabolism of serotonin and
subsequently enhance metabolic and cognitive functions in healthy older adults. The acute
effects of this dietary protein will be investigated in subjects with mild cognitive
impairment (MCI), or dementia, compared to control subjects in order to examine whether
healthy older subject with MCI benefit more from the intake of alpha-lactalbumin and/or whey.
The investigators will investigate if this meal can optimize serotonin metabolism by
elevating plasma TRP levels and plasma TRP appearance and enhance splanchnic TRP extraction.
In addition, the effects on mood and cognitive functions will be examined.
The study involves for all subjects 3 test days (approximately 8 hours each). On this test
day the investigators will examine the acute effects of a protein meal. Subjects will receive
a mixture of alpha-lactalbumin and/or whey and/or casein, carbohydrates and amino acid stable
isotopes to investigate protein and amino acid kinetics (assigned to alpha-lactalbumin or
whey or casein group on test day 1, then switch on test day 2 and 3). The subjects will
receive these stable isotopes by infusion in their blood and by oral intake (e.g.
simultaneously with protein meal). For study purposes, blood will be drawn approx. 25 times
during 8 hours on the test day, altogether about 100-120 ml of blood will be drawn on the
test day.
day the investigators will examine the acute effects of a protein meal. Subjects will receive
a mixture of alpha-lactalbumin and/or whey and/or casein, carbohydrates and amino acid stable
isotopes to investigate protein and amino acid kinetics (assigned to alpha-lactalbumin or
whey or casein group on test day 1, then switch on test day 2 and 3). The subjects will
receive these stable isotopes by infusion in their blood and by oral intake (e.g.
simultaneously with protein meal). For study purposes, blood will be drawn approx. 25 times
during 8 hours on the test day, altogether about 100-120 ml of blood will be drawn on the
test day.
Inclusion criteria subjects with dementia:
- Dementia diagnosis
- Ability to walk, sit down and stand up independently
- Age 55 years or older
- Ability to lie in supine or elevated position for 8 hours
- Willingness and ability to comply with the protocol, including:
Adhering to fasting state from 10 pm ± 2h onwards the day prior to each study visit
Inclusion criteria healthy subjects:
- Healthy male or female according to the investigator's or appointed staff's judgment
- Ability to walk, sit down and stand up independently
- Age 55 years or older
- Ability to lie in supine or elevated position for 8 hours
- Willingness and ability to comply with the protocol, including:
Adhering to fasting state from 10 pm ± 2h onwards the day prior to each study visit
Exclusion Criteria:
- Any condition that may interfere with the definition 'healthy subject' according to
the investigator's judgment (for healthy control group only)
- Failure to give informed consent or Investigator's uncertainty about the willingness
or ability of the subject to comply with the protocol requirements
- Indication of severe cognitive impairment (MOCA score < 17)
- Established diagnosis of Insulin Dependent Diabetes Mellitus
- History of untreated metabolic disease(s) including hepatic or renal disorder
- Presence of acute illness or metabolically unstable chronic illness
- Presence of fever within the last 3 days
- Preplanned surgery of procedures that would interfere with the conduct of the study
- Any other condition according to the PI or study physician that would interfere with
proper conduct of the study / safety of the patient
- Current alcohol or drug abuse
- Known allergy to milk or milk products
- Use of long-term oral corticosteroids or short course of oral corticosteroids 4 weeks
preceding first test day
- Use of protein or amino acid containing nutritional supplements within 5 days of test
day
- (Possible) pregnancy
- BMI of < 18.5 or ≥ 40 kg/m2
- Dietary or lifestyle characteristics: When during the period from enrollment to
completion of the study (end of test day) any condition is developed, whether causing
the subject to not meet inclusion criteria or to meet exclusion criteria, the subject
will be excluded from the study
We found this trial at
1
site
Click here to add this to my saved trials
