Acute Plasma Abeta Responses to Stress

NCT05521919 | Completed

• 1 other identifier: UP-22-00404
• Study Type: interventional
• Target: 38
• Locations: 1 country
• Sites: 1

Brief Summary

Research has shown that activation of the sympathetic nervous system for extended periods or during certain times in life can increase the risk for Alzheimer's disease. Some research in animal models show that acute activation of the sympathetic nervous system through stress exposure can increase certain Alzheimer's disease-related biomarkers, such as amyloid-beta, within hours of exposure. However, how acute sympathetic nervous system activation via stress exposure affects amyloid-beta levels in humans has yet to be examined. In this study, the investigators will examine whether brief increases in sympathetic activation result in immediate changes in plasma amyloid-beta levels in the five hours after exposure.

Conditions

Stress Reaction; Stress Physiology

Keywords

Stress Reaction; Stress; Amyloid-Beta

Outcome Measures

Primary Outcomes (2)

• Plasma amyloid-beta-40

  Changes in levels of amyloid-beta-40 in blood from before to after acute intervention (stress/no-stress).

  9.5 hours

• Plasma amyloid-beta-42

  Changes in levels of amyloid-beta-42 in blood from before to after acute intervention (stress/no-stress).

  9.5 hours

Study Arms (2)

Stress (sympathetic nervous system activation)

EXPERIMENTAL

Stress will be induced using the socially evaluated cold pressor test. Participants will complete three rounds of the socially evaluated cold pressor test. The socially evaluated cold pressor test involves submerging one hand in ice-cold water for 3 minutes while participants' reactions are filmed on camera.

Behavioral: Sympathetic Nervous System Activation

No-stress

SHAM COMPARATOR

Participants will hold a hand in room temperature water for 3 minutes.

Behavioral: No-stress

Interventions

Sympathetic Nervous System Activation BEHAVIORAL

Participants will complete a task that increases sympathetic nervous system activation.

Stress (sympathetic nervous system activation)

No-stress BEHAVIORAL

Participants will complete a task that will not affect their sympathetic nervous system activity.

No-stress

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Healthy adult weighing at least 110 pounds
• No chronic conditions or illness
• Taking no medications or drugs that might alter the stress response (e.g., corticosteroids, beta-blockers, and others)
• Not using any hormone-containing medication (e.g., hormonal contraceptives, hormone replacement, etc.)
• No contraindications for cold pressor test exposure (high blood pressure, heart disease, dysrhythmia, peripheral vascular disease, any other cardiovascular disorder, diabetes, vasculitis, lupus, tingling or numbness in the hands and/or feet, cryoglobulinemia, and Reynaud's phenomenon)
• No history of fainting during blood draws
• No phobia of having their blood drawn
• No general history of fainting or seizures
• Not currently diagnosed with a mood disorder (e.g., major depressive disorder)
• Not pregnant in the past 12 months
• Not lactating in the past 12 months
• Not trying to become pregnant if premenopausal
• Experienced natural menopause if postmenopausal
• Be non-smokers
• Be fluent in English

You may not qualify if:

• \- Unwilling to be filmed during the stress task OR unwilling to sign the waiver allowing their filmed responses to be used in scientific presentations

Sponsors & Collaborators

• University of Southern California: lead
• Washington University School of Medicine: collaborator
• Keck School of Medicine of USC: collaborator

Study Sites (1)

University of Southern California

Los Angeles, California, 90089, United States

Location

MeSH Terms

Conditions

Fractures, Stress; Plaque, Amyloid

Condition Hierarchy (Ancestors)

Fractures, Bone; Wounds and Injuries; Pathological Conditions, Anatomical; Pathological Conditions, Signs and Symptoms

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor of Gerontology, Psychology, and Biomedical Engineering

Model Details: Participants will complete one session of each condition: stress and no-stress. Participants will be randomly assigned to one of the two conditions for their first session. Participants will then be randomly assigned to the remaining condition for the second session.

Study Record Dates

• First Submitted: August 26, 2022
• First Posted: August 30, 2022
• Study Start: December 5, 2023
• Primary Completion: December 10, 2024
• Study Completion: December 10, 2024
• Last Updated: December 10, 2025

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will share
• Time Frame: Data will be made available by publication of the paper reporting on the results.
• Access Criteria: Publicly available.

Locations

US (1)