Very Long-chain Acyl-CoA Dehydrogenase Deficiency, Trifunctional Protein Deficiency, Long-chain 3-hydroxyacyl-CoA Dehydrogenase Deficiency, Medium-chain Acyl-CoA Dehydrogenase Deficiency, Normal Volunteers, Carnitine Palmitoyltransferase II Deficiency, Myopathic
Conditions
Brief summary
The purpose of this study is to learn more about what causes insulin resistance. It has been suggested that proper breakdown of fat into energy (oxidation) in the body is important to allow insulin to keep blood sugar in the normal range. The investigators want to know if having one of the fatty acid oxidation disorders could have an influence on insulin action. Fatty acid oxidation disorders are genetic disorders that inhibit one of the enzymes that converts fat into energy. The investigators will study both normal healthy people and people with a long-chain fatty acid oxidation disorder.
Detailed description
The overall goal of this proposal is to investigate the effects of disordered mitochondrial fatty acid oxidation on insulin resistance in humans. Mitochondrial dysfunction has been implicated in the development of insulin resistance and type 2 diabetes during excess dietary fat intake and from increased release of endogenous free fatty acids , such as occurs in obesity. Controversy exists, however, as to whether this insulin resistance results from intrinsic defects in mitochondrial energy utilization or from abnormalities resulting from excess free fatty acid flux, as well as the role that subsequent accumulation of cellular metabolic intermediates play in impaired insulin signaling. To address these controversies, the investigators will study a unique population of patients with inherited defects in each of the three mitochondrial enzymes in the fatty acid oxidation pathway: 1) very long-chain acyl-CoA dehydrogenase (VLCAD); 2) trifunctional protein (TFP, which includes long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD)); and 3) medium-chain acyl-CoA dehydrogenase (MCAD). These proteins are required for the oxidation of sequentially shorter fatty acids . The investigators will test the hypothesis that intrinsic defects in mitochondrial function involving oxidation of long-chain, but not medium-chain, fatty acids are sufficient to prevent intralipid-induced insulin resistance.
Interventions
DRUGIntralipid/Heparin
Co-infusion of intralipid and heparin solutions during a hyperinsulinemic euglycemic clamp
DRUGGlycerol/Saline
Co-infusion of a glycerol/saline solutions during a hyperinsulinemic euglycemic clamp
Infusion of insulin at at 40 mU/m2/min for 5 hours. Blood glucose will be monitored every 5 min during the insulin infusion and euglycemia will be maintained throughout the clamp by infusing 20% dextrose at a variable rate.
Sponsors
Oregon Health and Science University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* confirmed diagnosis of VLCAD, LCHAD, TFP or MCAD deficiency or same gender, age and BMI as a subject with a fatty acid oxidation disorder * ability to travel to Oregon Health & Science University, Portland, Oregon * ability and willingness to complete the protocol
Exclusion criteria
* hemoglobin \<10g/dl, international normalized ratio (INR) \>1.2 Prothrombin time (PTT) \>36 sec, Platelets \<150K/mm3 * pregnant or lactating females * endocrine disorder such as diabetes or untreated thyroid disease * cardiovascular disease or elevated plasma lipids * regularly taking meds that strongly affect bleeding, bruising or platelets
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Glucose Disposal Rate (Rd)- the Rate of Glucose Infusion to Maintain Euglycemia During Steady State Insulin Infusion in mg/Min | Calculated during the last 30 minutes of a 300 minute clamp. | Insulin infusion induces glucose disposal into muscle and adipose tissue in insulin sensitive participants. During the glycerol co-infusion, glucose disposal will be high. Intralipid co-infusion can induce a temporary insulin resistant state. During the intralipid co-infusion, glucose disposal will be decreased. We are comparing how intralipid dampens glucose disposal between participants with a FAOD and matched control participants. Glucose disposal is measured by measuring the ratio of deuterated glucose to unlabeled glucose at the beginning and end of the clamp. The calculated glucose disposal rate or RD is mg of glucose taken into muscle and adipose tissue per minute. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Endogenous Glucose Production (Ra) - Calculated by the Equations of Steele During Steady State in mg/Min | Calculated during the last 30 minutes of a 300 minute clamp. | Infusion of insulin will suppress endogenous glucose production from the liver in insulin sensitive people. Insulin infusion with glycerol should suppress the endogenous glucose production in the liver but intralipid induces a temporary state of insulin resistance and the decrease in endogenous glucose production or Ra will be blunted with intralipid co-infusion. We are looking at the difference in Ra with intralipid between participants with a FAOD and matched control participants. Ra or endogenous glucose production during high insulin is measured in mg new glucose synthesized per minute. |
Countries
United States
Participant flow
Recruitment details
2 control participants were recruited between February 2016 and June 2016 to complete testing of the protocol procedures. Adjustments to clamp, MRS and biopsy protocols were made and a final manual of operating procedures developed. These 2 participants were not included in the final data analysis. Then, 23 participants with a FAOD were screened for eligibility from June 2016 to August 2019. 27 control participants were screened for eligibility from July 2016 to February 2020.
Pre-assignment details
2 initial control participants who did not have a comparable FAO matched participant completed the protocol procedures to establish the final protocol; the data was not included in the final analysis. 23 participants with a FAOD were randomized. Of those randomized, 2 did not meet inclusion criteria, and 2 declined to participate. 27 control participants were randomized. Of those randomized, 2 did not meet inclusion criteria and 3 declined to participate.
Participants by arm
| Arm | Count |
|---|---|
| FAOD Glycerol Then Intralipid Participants with a FAOD first complete a hyperinsulinemic euglycemic clamp with a co-infusion of glycerol. After a wash-out of 4 months, they then complete a a hyperinsulinemic euglycemic clamp with a co-infusion of intralipid. | 11 |
| FAOD Intralipid Then Glycerol Participants with a FAOD first complete a hyperinsulinemic euglycemic clamp with a co-infusion of intralipid. After a wash-out of 4 months, they then complete a a hyperinsulinemic euglycemic clamp with a co-infusion of glycerol. | 8 |
| Control Glycerol Then Intralipid Matched control participants first complete a hyperinsulinemic euglycemic clamp with a co-infusion of glycerol. After a wash-out of 4 months, they then complete a a hyperinsulinemic euglycemic clamp with a co-infusion of intralipid. | 11 |
| Control Intralipid Then Glycerol Matched control participants first complete a hyperinsulinemic euglycemic clamp with a co-infusion of intralipid. After a wash-out of 4 months, they then complete a a hyperinsulinemic euglycemic clamp with a co-infusion of glycerol. | 11 |
| Total | 41 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 | FG002 | FG003 |
|---|---|---|---|---|---|
| Overall Study | Protocol Violation | 0 | 0 | 1 | 1 |
| Overall Study | Withdrawal by Subject | 1 | 0 | 1 | 0 |
Baseline characteristics
| Characteristic | FAOD Glycerol Then Intralipid | FAOD Intralipid Then Glycerol | Control Glycerol Then Intralipid | Control Intralipid Then Glycerol | Total |
|---|---|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical Between 18 and 65 years | 11 Participants | 8 Participants | 11 Participants | 11 Participants | 41 Participants |
| Age, Continuous | 32.0 years STANDARD_DEVIATION 12.7 | 23.0 years STANDARD_DEVIATION 4.3 | 33.8 years STANDARD_DEVIATION 9.4 | 29.9 years STANDARD_DEVIATION 10.8 | 29.32 years STANDARD_DEVIATION 9.48 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 6 Participants | 5 Participants | 11 Participants | 10 Participants | 32 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 5 Participants | 3 Participants | 0 Participants | 1 Participants | 9 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants | 1 Participants | 1 Participants |
| Race (NIH/OMB) Asian | 0 Participants | 0 Participants | 0 Participants | 1 Participants | 1 Participants |
| Race (NIH/OMB) Black or African American | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants | 1 Participants | 1 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 4 Participants | 3 Participants | 1 Participants | 2 Participants | 10 Participants |
| Race (NIH/OMB) White | 7 Participants | 5 Participants | 10 Participants | 6 Participants | 28 Participants |
| Region of Enrollment United States | 11 participants | 8 participants | 11 participants | 11 participants | 41 participants |
| Sex: Female, Male Female | 4 Participants | 3 Participants | 3 Participants | 6 Participants | 16 Participants |
| Sex: Female, Male Male | 7 Participants | 5 Participants | 8 Participants | 5 Participants | 25 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk | EG003 affected / at risk |
|---|---|---|---|---|
| deaths Total, all-cause mortality | 0 / 19 | 0 / 18 | 0 / 20 | 0 / 21 |
| other Total, other adverse events | 13 / 19 | 12 / 18 | 11 / 20 | 13 / 21 |
| serious Total, serious adverse events | 1 / 19 | 2 / 18 | 0 / 20 | 1 / 21 |
Outcome results
Primary
Glucose Disposal Rate (Rd)- the Rate of Glucose Infusion to Maintain Euglycemia During Steady State Insulin Infusion in mg/Min
Insulin infusion induces glucose disposal into muscle and adipose tissue in insulin sensitive participants. During the glycerol co-infusion, glucose disposal will be high. Intralipid co-infusion can induce a temporary insulin resistant state. During the intralipid co-infusion, glucose disposal will be decreased. We are comparing how intralipid dampens glucose disposal between participants with a FAOD and matched control participants. Glucose disposal is measured by measuring the ratio of deuterated glucose to unlabeled glucose at the beginning and end of the clamp. The calculated glucose disposal rate or RD is mg of glucose taken into muscle and adipose tissue per minute.
Time frame: Calculated during the last 30 minutes of a 300 minute clamp.
Population: 1 participant with a FAOD withdrew after completing the glycerol clamp . 2 control participants completed the protocol to establish the study procedures, but are not included in the statistical analysis. 1 control participants withdrew and 1 was discontinued leaving 18 participants data for the intralipid clamp. In addition, 1 other control was discontinued and 1 control had technical challenges during the glycerol clamp leaving 16 control participants data for glycerol clamp.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Glycerol/Saline FAOD | Glucose Disposal Rate (Rd)- the Rate of Glucose Infusion to Maintain Euglycemia During Steady State Insulin Infusion in mg/Min | 709 mg/min | Standard Deviation 244 |
| Intralipid FAOD | Glucose Disposal Rate (Rd)- the Rate of Glucose Infusion to Maintain Euglycemia During Steady State Insulin Infusion in mg/Min | 429 mg/min | Standard Deviation 297 |
| Glycerol/Saline Control | Glucose Disposal Rate (Rd)- the Rate of Glucose Infusion to Maintain Euglycemia During Steady State Insulin Infusion in mg/Min | 842 mg/min | Standard Deviation 282 |
| Intralipid Control | Glucose Disposal Rate (Rd)- the Rate of Glucose Infusion to Maintain Euglycemia During Steady State Insulin Infusion in mg/Min | 497 mg/min | Standard Deviation 297 |
Comparison: We compared the effects of intralipid on Rd in controls subjects versus subjects with a FAOD by mixed-effect models. Factors were group (control or FAOD) treatment (glycerol or intralipid) and the interaction of those factors. The hypothesis was intralipid would decrease Rd in controls but not in subjects with an FAOD.p-value: 0.136Mixed Models Analysis
Secondary
Endogenous Glucose Production (Ra) - Calculated by the Equations of Steele During Steady State in mg/Min
Infusion of insulin will suppress endogenous glucose production from the liver in insulin sensitive people. Insulin infusion with glycerol should suppress the endogenous glucose production in the liver but intralipid induces a temporary state of insulin resistance and the decrease in endogenous glucose production or Ra will be blunted with intralipid co-infusion. We are looking at the difference in Ra with intralipid between participants with a FAOD and matched control participants. Ra or endogenous glucose production during high insulin is measured in mg new glucose synthesized per minute.
Time frame: Calculated during the last 30 minutes of a 300 minute clamp.
Population: 1 participant with a FAOD withdrew after completing the glycerol clamp . 2 control participants completed the protocol to establish the study procedures, but are not included in the statistical analysis. 1 control withdrew and 1 was discontinued leaving 18 participants data for the intralipid clamp. In addition, 1 other control was discontinued and 1 control had technical challenges during the glycerol clamp leaving 16 control participants data for the glycerol clamp.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Glycerol/Saline FAOD | Endogenous Glucose Production (Ra) - Calculated by the Equations of Steele During Steady State in mg/Min | 84.7 mg/min | Standard Deviation 38.4 |
| Intralipid FAOD | Endogenous Glucose Production (Ra) - Calculated by the Equations of Steele During Steady State in mg/Min | 97.2 mg/min | Standard Deviation 44 |
| Glycerol/Saline Control | Endogenous Glucose Production (Ra) - Calculated by the Equations of Steele During Steady State in mg/Min | 50.2 mg/min | Standard Deviation 42 |
| Intralipid Control | Endogenous Glucose Production (Ra) - Calculated by the Equations of Steele During Steady State in mg/Min | 106 mg/min | Standard Deviation 37 |
Comparison: We tested if intralipid did not suppress endogenous glucose production or Ra as much as glycerol in controls compared to subjects with an FAOD.p-value: 0.011Mixed Models Analysis