Exploring the Cognitive Benefits of a Blackcurrant-Based Supplement in Normobaric Hypoxia

NCT ID: NCT07166835

Last Updated: 2025-09-10

Basic Information

• Recruitment Status: NOT_YET_RECRUITING
• Clinical Phase: NA
• Total Enrollment: 27 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2025-09-01
• Study Completion Date: 2027-10-01

Brief Summary

This study investigates the cognitive effects of Ārepa, a blackcurrant-based drink, under simulated high-altitude conditions (4,500m normobaric hypoxia for ~180 minutes). Using a double-blind, randomised, placebo-controlled crossover design, participants will consume either the nootropic blackcurrant-based drink or a taste-matched placebo. Cognitive testing (~80 minutes) includes Trail-making, Stroop, N-back, Serial 7s/3s, and RVIP tasks. Physiological measures (heart rate, SpO₂, blood) and biomarkers (MAO-B, BDNF, hsCRP, S100B, Prolactin, C3G, Sarmentosin) will be assessed. Scales will evaluate mood, wellbeing, and perceived effects. The aim is to determine if the nootropic drink can support cognitive function in hypoxic environments.

Detailed Description

Cognitive functioning can be influenced by varying factors including age, education, fatigue and environmental conditions. It is well established that stress, including hypoxia, sleep deprivation, and mental fatigue, alters brain energetics therefore resulting in a decline of cognitive function. Any physical or psychological stressor that disrupts homeostasis results in a stress response. Altitude, often associated with sports, recreational activities and holidaying, refers to environments where the partial pressure of oxygen (pO2) is reduced relative to sea level. The effects of high altitude on humans are mostly the consequences of reduced pO2 in the atmosphere and can result in fatigue, dizziness and debilitating cognitive consequences to unacclimatised individuals. These effects can significantly impair cognitive and physical performance at high elevations. In this context, interests in prophylactic use of dietary interventions to mitigate the effects of oxygen deprivation has increased in recent years. Interventions utilising a number of plant derived phytochemicals have demonstrated some protective efficacy against these physiological insults and may be capable of attenuating cognitive function and mood under hypoxic stress. However, there is limited research available on polyphenol supplementation to support cognition at high altitudes. Therefore, the purpose of the study is to explore the possibility of the nootropic drink and how effective it is in reducing cognitive impairment of healthy males at a simulated high altitude of 4,500m.

Participants will attend the laboratory on four occasions over a 2-3-week period. The first two visits will involve a pre-screening assessment and a familiarisation session with the experimental procedures and cognitive tasks.

The subsequent two visits will serve as the experimental trials, during which participants will be exposed to a normobaric hypoxic environment simulating an altitude of 4,500 meters. This condition is achieved by maintaining sea-level barometric pressure with a reduced inspired oxygen fraction (FiO₂ ~11.3%, equivalent to a PiO₂ of approximately 80.9 mmHg).

Acute exposure to high altitudes (3,000-4,500 m) for durations as short as 45 to 120 minutes has been shown to impair cognitive function, increase mood disturbances, reduce task accuracy, and slow reaction times. Based on prior research the duration of hypoxic exposure in this study will be approximately 180 minutes, allowing sufficient time for potential cognitive changes to occur.

Each experimental trial will follow a double-blind, randomised, placebo-controlled crossover design. Participants will consume 100 mL of either an anthocyanin-rich blackcurrant drink (containing 200 mg of bioactive compounds) or a taste- and appearance-matched placebo (0 mg). A 45-minute rest period will follow to allow for absorption.

Cognitive testing will span approximately 80 minutes and will begin 75 minutes into the hypoxic exposure. This includes three short tasks (approximately 10 minutes in total) administered before and after a 60-minute cognitive demand battery. The cognitive tasks will assess executive function, working memory, attention, and cognitive load.

Physiological measures (e.g., heart rate, SpO₂), blood-based biomarkers (e.g., MAO-B, BDNF, hsCRP, S100B, prolactin, C3G, sarmentosin), and self-reported scales assessing mood, anxiety, perceived cognitive workload, and subjective effects will also be collected throughout the trial.

Conditions

Cognitive Performance; Executive Function (Cognition); Working Memory; Hypoxia Induced Cognitive Impairment; Mood

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: SUPPORTIVE_CARE
• Blinding Strategy: DOUBLE

Study Groups

Nootropic drink

Nootropic beverage containing anthocyanins, L-theanine, and Enzogenol. Administered orally prior to cognitive testing under simulated normobaric hypoxia.

Group Type: ACTIVE_COMPARATOR

Nootropics (ginkgo biloba, nicergoline, piracetam, or others)

Intervention Type: DIETARY_SUPPLEMENT

Nootropic drink containing Anthrocyanins, L-theanie and Enzogenol

Placebo drink

Taste- and appearance-matched placebo beverage without active ingredients. Administered orally prior to cognitive testing under simulated normobaric hypoxia.

Group Type: PLACEBO_COMPARATOR

Placebo

Intervention Type: DIETARY_SUPPLEMENT

Taste- and appearance-matched placebo beverage without active ingredients.

Interventions

Nootropics (ginkgo biloba, nicergoline, piracetam, or others)

Nootropic drink containing Anthrocyanins, L-theanie and Enzogenol

Intervention Type: DIETARY_SUPPLEMENT

Placebo

Taste- and appearance-matched placebo beverage without active ingredients.

Intervention Type: DIETARY_SUPPLEMENT

Eligibility Criteria

Inclusion Criteria

• Willing and able to provide written informed consent (in English)
• Aged 18-35
• Male
• Residing at a low altitude (<500m)

Exclusion Criteria

• Diagnosed food allergy or intolerance to the investigational products or control products. (Blackcurrant, food allergen/ pine, tree-derived allergen/ l-theanine tree allergen (camellia sinensis))
• Significant past medical and psychiatric history and ongoing chronic conditions such as, cardiovascular disease, respiratory disease, endocrine disorder (e.g. Diabetes mellites) and neurological and psychiatric conditions including brain injury or are colourblind.
• Significant medication history or current prescription of medication or supplements known to affect cognition such as. Sedatives, stimulants, or herbal supplements high in anthocyanin and polyphenol content.
• A positive result from the pre-screening sickle cell trait blood test.
• An abnormal ECG reading.
• A resting heart rate above 100bmp.
• A blood pressure reading above 140/90mmHg.
• Subjects not willing and/ or not able to comply with the scheduled visits required for the study.
• Not willing to provide blood samples.
• Not classified as low risk based on the ACSM guidelines.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 35 Years
• Eligible Sex: MALE
• Accepts Healthy Volunteers: Yes

Sponsors

Leeds Beckett University

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Locations

Leeds Beckett University

Leeds, , United Kingdom

Countries

United Kingdom

Central Contacts

Isobel R Harris

Role: CONTACT

i.harris@leedsbeckett.ac.uk

+44 7443518358

Facility Contacts

Isobel R Harris

Role: primary

i.harris@leedsbeckett.ac.uk

+44 7443518358

Other Identifiers

151421

Identifier Type: -

Identifier Source: org_study_id