An interventional study of SFA diet and MUFA diet in Insulin Resistance, sponsored by Phoenix VA Health Care System. Status unknown at 1 site in United States. Open to participants aged 40 Years to 75 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2019-08-01.
Sponsored by Phoenix VA Health Care System · Not applicable, Interventional, and Basic science
The overall goal of the proposal is to use a saturated fatty acid (SFA)- enriched, high fat diet to rapidly induce insulin resistance (IR) to provide insight into underlying proximal mechanisms of reduced insulin signaling. Specifically, investigators will identify the initial changes in metabolite concentrations/or pathway signaling ("pathways" will be used to broadly refer to these mechanism specific measures) and therefore the mechanisms most likely responsible for the development of IR during this high fat nutritional challenge. Investigators have assembled a multidisciplinary team that is versed with dietary studies, fatty acid metabolism, measurement of IR and potential mechanisms and mediators of IR, and has experience working with monocytes and the two tissues, muscle and adipose tissue, that are particularly relevant for understanding the effects of high fat diets on IR.
In the first aim, investigators will test whether a short-term high SFA-diet induces and increases insulin resistance in participants with normal and abnormal glucose tolerance, respectively, and determine the associated changes in muscle, adipose tissue and inflammatory cell composition, pathway activation and insulin signaling. Investigators will identify changes in specific signal pathways within these tissues and cells that are hypothesized to mediate or modulate insulin action. Primary mechanisms and pathways examined will include local tissue and systemic inflammation, formation of bioactive lipid intermediates, generation of endoplasmic reticulum (ER) stress, and mitochondrial dysfunction/reactive oxygen formation. By performing studies in participants with normal glucose tolerance and in those with abnormal glucose tolerance investigators will also determine whether the extent and mechanisms of insulin resistance vary with initial degrees of glucose intolerance.
In the second aim, to determine if the extent and mechanisms of insulin resistance vary with dietary composition, investigators will determine whether diets of similar caloric content as the SFA-diet, but enriched in monounsaturated fatty acids or carbohydrates, also induce insulin resistance and whether similar or different mechanistic pathways are responsible. Identifying similarities and differences between diets in inflammatory cell and tissue changes and comparing their relationships with peripheral and tissue insulin action will further clarify which cell and tissue events are most closely linked to development of insulin resistance.
In the final aim, to identify the temporal sequence of mechanistic pathways for insulin resistance and the role of cell and tissue cross-talk in these events, investigators will evaluate inflammatory cell, skeletal muscle and adipose tissue composition and pathway changes after acute, subacute, and more chronic dietary challenges in the same individuals. This will also permit assessment of whether repeated dietary challenges create changes in tissues that resemble those found in more chronic and advanced states of insulin resistance.
2,969 studies on the registry are indexed under Insulin Resistance; 338 are open to participants now.
This study's planned enrollment of 300 is above the median of 40 across 2,369 interventional studies indexed under Insulin Resistance.
Browse Insulin Resistance studies →Phoenix VA Health Care System is the lead sponsor of 9 studies on the registry; none are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HbA1c
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will be randomized in a cross-over design to either a weight-maintaining, nutritionally-balanced American Heart Association based eucaloric control diet or a high calorie 24-hour saturated fatty acids enriched diet. For the control diet participants will follow a dietary plan for 72 hours prior to testing. For the SFA diet, participants will be provided with high caloric liquid shakes for breakfast, lunch, dinner and a bedtime snack. On the morning of each test day, participants will be admitted in the fasting state and will provided with a breakfast meal corresponding to the assigned diet (SFA or control). Three hours after completion of the meal, insulin sensitivity will be measured by insulin-suppression test (IST).
Other: SFA diet
Participants will be randomized in a cross-over design to either a weight-maintaining, nutritionally-balanced American Heart Association based eucaloric control diet or a high calorie 24-hour monounsaturated fatty acids (MUFA) enriched diet. For the control diet participants will follow a dietary plan for 72 hours prior to testing. For the MUFA diet, participants will be provided with high caloric liquid shakes for breakfast, lunch, dinner and a bedtime snack. On the morning of each test day, participants will be admitted in the fasting state and will provided with a breakfast meal corresponding to the assigned diet (MUFA or control). Three hours after completion of the meal, insulin sensitivity will be measured by insulin-suppression test (IST).
Other: MUFA diet
Participants will be randomized in a cross-over design to either a weight-maintaining, nutritionally-balanced American Heart Association based eucaloric control diet or a high calorie 24-hour carbohydrate (CARB) enriched diet. For the control diet participants will follow a dietary plan for 72 hours prior to testing. For the CARB diet, participants will be provided with high caloric liquid shakes for breakfast, lunch, dinner and a bedtime snack. On the morning of each test day, participants will be admitted in the fasting state and will provided with a breakfast meal corresponding to the assigned diet (CARB or control). Three hours after completion of the meal, insulin sensitivity will be measured by insulin-suppression test (IST).
Other: CARB diet
SFA versus control diet
MUFA versus control diet
CARB versus control diet
Steady-state plasma glucose (SSPG)
Average plasma glucose concentrations during min 150-180 of the insulin suppression test (IST)
Time frame: 150-180 min
Acylcarnitine species
Measured by chromatography electrospray ionization mass spectrometry on plasma and skeletal muscle samples.
Time frame: Overnight fast, 3-hour post breakfast
Diacylglycerol species
Measured on plasma, skeletal muscle and subcutaneous adipose tissue samples.
Time frame: Overnight fast, 3-hour post breakfast
Ceramides species
Measured on plasma, skeletal muscle and subcutaneous adipose tissue samples.
Time frame: Overnight fast, 3-hour post breakfast
Insulin signaling proteins
Measured on skeletal muscle and subcutaneous adipose tissue samples.
Time frame: Overnight fast, 3-hour post breakfast
Inflammation markers
Cytokines and adipokines will be measured in plasma after the diet treatments by ELISA techniques. Mononuclear cells inflammatory gene expression will be measured by real time polymerase chain reaction (RT-PCR). Inflammation will be measured in muscle and adipose tissue by RT-PCR and Western blood analysis.
Time frame: Overnight fast, 3-hour post breakfast
Plan to share: No — Subject to VA regulation.
No publications or documents are linked to this record.
The record gives a start of Feb 2012, a primary completion of Jul 2020 and a completion of Dec 2020. It does not say whether these dates are actual or estimated.
How these figures are worked out, and which studies are left out of them.
This study is status unknown, as verified in Jul 2019. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Phoenix VA Health Care System