NCT05153395

Brief Summary

The purpose of this project is to examine the impact of increases in brain insulin on sympathetic nervous system activity, as well as peripheral and cerebral blood flow in humans.

Trial Health

53
Monitor

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial recruitment is currently suspended
Enrollment
65

participants targeted

Target at P75+ for early_phase_1 healthy

Timeline
13mo left

Started Dec 2021

Longer than P75 for early_phase_1 healthy

Geographic Reach
1 country

1 active site

Status
suspended

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Progress81%
Dec 2021Jun 2027

First Submitted

Initial submission to the registry

November 18, 2021

Completed
13 days until next milestone

Study Start

First participant enrolled

December 1, 2021

Completed
9 days until next milestone

First Posted

Study publicly available on registry

December 10, 2021

Completed
5.5 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

June 1, 2027

Expected
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

June 1, 2027

Last Updated

December 19, 2025

Status Verified

December 1, 2025

Enrollment Period

5.5 years

First QC Date

November 18, 2021

Last Update Submit

December 12, 2025

Conditions

HealthyVasodilationInsulin ResistanceAutonomic DysfunctionObesity

Outcome Measures

Primary Outcomes (1)

  • Amount of cerebral blood flow

    Measured with trans-cranial Doppler ultrasound (cm/s) or arterial spin labeling (mL/100 g/min)

    Change from baseline at minute 15

Secondary Outcomes (2)

  • Amount of muscle sympathetic nerve activity (MSNA)

    Change from baseline at minute 15

  • Amount of leg blood flow

    Change from baseline at minute 15

Study Arms (3)

Insulin (Doppler)

EXPERIMENTAL

Human insulin (160 IU) will be administered as a bolus using an intra-nasal device.

Other: Carbon dioxide breathingOther: Neurovascular CouplingDrug: Human insulin

Insulin (MRI)

EXPERIMENTAL

Human insulin (160 IU) will be administered as a bolus using an intra-nasal device.

Other: Carbon dioxide breathingDrug: Human insulin

Time Control (Doppler)

OTHER

Time control only

Other: Carbon dioxide breathingOther: Neurovascular Coupling

Interventions

Carbon dioxide breathingOTHER

Hypercapnic (5% carbon dioxide) air will be administered before and after intra-nasal insulin exposure.

Insulin (Doppler)Insulin (MRI)Time Control (Doppler)
Neurovascular CouplingOTHER

Participants will be asked to repeatedly open and close their eyes. With eyes open, participants will focus on a visual image. This will be done before and after intra-nasal insulin exposure.

Insulin (Doppler)Time Control (Doppler)
Human insulinDRUG

Participants will be administered human insulin (160 IU) as a bolus using an intra-nasal device.

Insulin (Doppler)Insulin (MRI)

Eligibility Criteria

Age18 Years - 45 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • healthy adult men and women;
  • years of age;
  • BMI \>18 kg/m2;
  • non-pregnant/non-breastfeeding;
  • non-nicotine users;

You may not qualify if:

  • taking any medications known to affect metabolic, respiratory, cardiovascular, and/or autonomic
  • Self-reported history of:
  • hepatic, renal, pulmonary, cardiovascular, or neurological disease;
  • stroke or neurovascular disease;
  • bleeding/clotting disorders;
  • sleep apnea or other sleep disorders;
  • diabetes;
  • smoking;
  • history of alcoholism or substance abuse;
  • hypertension;
  • respiratory disease;
  • active cancer;
  • autoimmune disease.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

University of Missouri

Columbia, Missouri, 65211, United States

Location

MeSH Terms

Conditions

AneurysmInsulin ResistancePrimary DysautonomiasObesity

Interventions

Neurovascular CouplingInsulin

Condition Hierarchy (Ancestors)

Vascular DiseasesCardiovascular DiseasesHyperinsulinismGlucose Metabolism DisordersMetabolic DiseasesNutritional and Metabolic DiseasesAutonomic Nervous System DiseasesNervous System DiseasesOverweightOvernutritionNutrition DisordersBody WeightSigns and SymptomsPathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Cerebrovascular CirculationBlood CirculationCardiovascular Physiological PhenomenaCirculatory and Respiratory Physiological PhenomenaProinsulinInsulinsPancreatic HormonesPeptide HormonesHormonesHormones, Hormone Substitutes, and Hormone AntagonistsPeptidesAmino Acids, Peptides, and Proteins

Study Officials

  • Jacqueline K Limberg, Ph.D.

    University of Missouri-Columbia

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
early phase 1
Allocation
NON RANDOMIZED
Masking
NONE
Purpose
BASIC SCIENCE
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Associate Professor

Study Record Dates

First Submitted

November 18, 2021

First Posted

December 10, 2021

Study Start

December 1, 2021

Primary Completion (Estimated)

June 1, 2027

Study Completion (Estimated)

June 1, 2027

Last Updated

December 19, 2025

Record last verified: 2025-12

Locations

US(1)