Plasma Lipids-Dependent Vitamin E Metabolism During Dynamic Hyperlipidemia

What this study involves

The registry does not currently label this study as recruiting. Ask about its status before planning a screening visit.

Study type

Interventional

Phase

Not applicable

Age range

18 years - 65 years

Sex eligible

All sexes

Healthy volunteers

Not accepted

Participants

48 Estimated

These are starting points, not an eligibility decision. The research team must review the full requirements.

About the research

Background:

Obesity is known to lead to diseases such as diabetes and high cholesterol (or fats) in the blood (hyperlipidemia). But no one knows why. Researchers think that high levels of fat in the blood may block important nutrients, such as vitamin E, from reaching places they are needed in the body.

Objective:

To learn how high-fat meals affect levels of vitamin E in the blood.

Eligibility:

People aged 18 to 65 with high blood fat levels. Healthy volunteers are also needed.

Design:

Participants will have 3 or 4 clinic visits in 3 months. The last visit will require them to stay in the clinic for 2 nights.

Participants will be screened. They will have a physical exam and blood tests.

After this visit, all participants must stop taking any dietary supplements.

Those who use them must also stop taking any drugs to lower their blood sugar and blood fats. These participants will have an extra visit for blood tests after 60 days.

The next visit will include 2 imaging scans:

Magnetic resonance imaging (MRI) of the abdomen. This scan will check for fat in the liver.

Dual-energy X-ray absorptiometry (DEXA). This scan measures the levels of body fat.

On day 1 of the clinic stay, participants will have 2 set meals, with nothing but water after 10 pm.

On day 2, they will drink high-fat shakes at 9am, 1pm, and 5pm. They will have blood draws every 30 minutes for the first hour, every hour the next 16 hours, and then every 2 hours until 7 am. The blood will be taken from a tube inserted into a vein and left in place for the day.

On day 3, they will go home.

Who may be able to participate?

The list below is the sponsor’s full registry wording. It can include conditions, prior treatment, test results and other requirements. A match in search does not mean you qualify.

• INCLUSION CRITERIA:

Cohort 1

• Males and females aged 18 to 65 years.
• BMI 18.5 26.9 kg/m\^2 .
• Able to understand the study procedures and provide written consent, and willing to comply with all scheduled follow-up visits and assessments.
• Normotensive and not on antihypertensive medications, blood pressure 90-129/60-84.
• Not on glucose-lowering or lipid-lowering medications.
• At screening, laboratory values meet all of the following:

• HbA1c \< 5.7%,
• Fasting triglycerides \< 150 mg/dL
• LDL \< 100 mg/dL

7\. Liver fat \< 2%.

Cohort 2

• Males and females aged 18 to 65 years.
• BMI \> 26.0 to \< 36.0 kg/m2.
• Able to understand the study procedures and provide written informed consent, and willing to comply with all scheduled follow-up visits and assessments.
• At screening, laboratory values meet all of the following:

• HbA1c \<= 7.5%
• Fasting triglycerides \< 500 mg/dL
• LDL \< 190 mg/dL
• Willing to discontinue oral glucose-lowering medications (metformin) and oral lipidlowering medications for 4 to 10 weeks prior to the inpatient visit, if applicable.
• Liver fat \< 2%.

EXCLUSION CRITERIA:

• Women who are pregnant or currently breastfeeding.
• Subjects younger than 18 years old. This age group has a broad spectrum of hormonal profiles due to development and puberty, which significantly increases the heterogenicity of study subjects.
• Subjects older than 65 years. This age group has significantly increased risk of cardiovascular diseases. To minimize the risk from temporarily suspending lipid- and glucose-lowering medications and the stress from serial blood draws, these individuals are excluded.
• Heavy alcohol use within past 12 months (males: \>2 drinks per day or \>14 drinks per week; females: \>1 drink per day or \>7 drinks per week).
• Current smoker, or former smoker who quit smoking less than 15 years ago.
• Subjects with weight changes greater than 20% of baseline body weight (self-reported or documented within past 12 months) over the past 3 months at outpatient visit 1, or change from outpatient visit 1 during screening.
• Subjects with lactose intolerance who are unwilling to take lactase.
• Subjects with type 1 diabetes.
• Subjects with hemoglobin \<11 g/dL or hematocrit \<33%.
• Subjects with clinically significant abnormal liver function test results.
• Subjects with liver fat \>= 2% on abdominal MRI.
• Subjects with a history of pancreatitis, diabetes ketoacidosis, hyperosmolar hyperglycemic state, advanced atherosclerosis, cardiovascular diseases, kidney diseases, or liver diseases.
• Subjects with fat malabsorption, including a history of gastrointestinal surgery, pancreatic insufficiency, inflammatory bowel disease, celiac disease, moderate-to-severe irritable bowel syndrome, or pathologic mutations impacting lipoprotein metabolism.
• Subjects on glucocorticoids for more than 1 week (not including topical glucocorticoids) within past 3 months.
• Subjects with HIV.
• Subjects with uncontrolled psychiatric and/or behavioral disorders.
• Subjects taking diabetes medications other than metformin.
• Subjects with anticipated surgery during the study period.
• Subjects with severe medication-resistant claustrophobia.
• Subjects who are unwilling to stop medications, vitamins, and/or dietary supplements that investigators have requested to be held.
• Subjects participating in any other clinical study without informing investigators.
• Any other reason or clinical condition that the investigators judge would interfere with study participation and/or be unsafe for the participant or staff member.

Treatment, groups and participation

The registry may describe treatments and study duration without a complete visit calendar. Ask the study team for the exact schedule, procedures, risks, costs and alternatives. Keep your usual care plan unless your treating clinician tells you otherwise.

Assignment

Not randomized

Masking

No masking

What researchers are measuring

Outcome measures describe what is being studied. They are not proof that a treatment works.

Primary measures

Secondary measures

Research locations (1)

The overall study status and a local site’s status can differ. Confirm that location’s availability before traveling.

1 locations

Study team and timeline

Lead sponsor

National Heart, Lung, and Blood Institute (NHLBI)

Study start

Nov 15, 2026 Estimated

Primary completion

Nov 30, 2028 Estimated

Study completion

Mar 31, 2029 Estimated

First posted

Jul 21, 2026 Actual

Last updated

Nov 10, 2026 Actual

Official study contacts