Glucose Production After Ingesting 13C-Labeled Glycerol

Study ID
STU 022012-073

Cancer Related
No

Healthy Volunteers
Yes

Study Sites

  • CTRC Outpatient
  • UT Southwestern-Other

Contact
Jeannie Baxter
214/645-2726
JEANNIE.BAXTER@UTSouthwestern.edu

Principal Investigator
Eunsook Jin, Ph.D.

Summary

We will recruit
* healthy
* over-weighted subjects (BMI >28) to increase the chance to find fatty liver. In general, lean subjects rarely have fatty liver, but we will include lean subjects with previously documented fatty liver.

Approximately 40 healthy volunteers will be consented, which will allow for screen failures. At least 10 subjects with fatty liver and 10 subjects with lean liver will be recruited. Each person will make two visits to the AIRC for screening and study procedures that will include ingestion of D2O, ingestion of [U-13C3]glycerol and an MRI exam on a 3T scanner for spectroscopic measurements of liver fat. The screening visit will take an hour and the study day visit will take approximately 6.5 hours. After the ingestion, blood will be drawn at the following time points: +30, +60, +90, +120, +180 min and +240 min. After the ingestion of the glycerol and during the blood draws, volunteers will be made comfortable in the AIRC procedure room.

Subjects will exit the study upon completion of procedures. Early withdrawal may result from inability to obtain venous access or intolerance of the glycerol or D2O. Subjects will sign a consent before any study procedures are performed.

Study Procedures:
All volunteers will make two visits to the AIRC.

Screening:

* Review Study Procedures.

* Sign Consent and HIPAA authorization.

* Urine pregnancy test, if applicable.

* Blood draw (~10 mL) for blood chemistry and CBC.

* Provide frozen meal (700 kcal) prepared by CRU (Clinical Research Unit) for the last meal. prior to overnight fast before the study day.

* Provide the 1st dose of 70% D2O for ingestion evening prior to Study Day.

Day Prior to Study Day (at home):

* Last meal at 6:30pm prior to overnight fast: frozen metabolic diet consisting of 700kcal (30% protein, 30% fat, 40% carbohydrate).

* Overnight fast to start at 7pm.

* At 9:30pm - ingestion of dose 1 of 70% D2O (total dose 5g/kg body weight over three doses: calculated as 60% body weight for men or 50% body weight for women).

* May continue to drink water ad lib until reports for study.
Study Day:

* Review Study Procedures.

* Urine pregnancy test, if applicable.

* Ingest the 2nd dose of D2O.

* Measure weight, height, waist circumference, vital signs etc.

* Ingest the 3rd dose of D2O.

* Liver fat measurement using 3TC MR scanner.

* IV insertion by AIRC nurse for blood draws.

* Baseline chemistry (10ml) and blood sugar (1 ml by YSI glucose analyzer).

* Ingest 50% [U-13C3]glycerol (50 mg/kg body weight).

* Blood draws: +30, +60, +90, +120, +180 min and +240 min. Each blood draw will be 41 mls. for glucose, NMR and blood chemistry. A total of approximately 300 ml. will be drawn over the course of the the study (includes 25 ml. waste).

* IV discontinued.

* Lunch and discharge from AIRC. Study participation completed. Duration approximately 6.5 hours. Research subjects will not be responsible for any costs of the study.

Participant Eligibility


* Age 30-60

* BMI > 28, or subject must have previously document fatty liver.

* Healthy

* English speaking. Participants must be able to understand instructions in English as translation for other languages is not available.