The Effect of Dietary Fat Load and Physical Exercise on the Flexibility and Partitioning of Ectopic Lipids.

NCT01467193 | Completed

• 1 other identifier: 234/10
• Study Type: observational
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

This study aims at assessing the effect of standardized dietary fat load and short-term aerobic exercise on systemic lipolysis, flexibility and partitioning of ectopic fat stores (intramyocellular = IMCL, intrahepatocellular = IHCL, intramyocardial lipids = IMCaL) in relation to FFA in endurance trained athletes and hypopituitary patients compared to sedentary healthy control subjects. Exercise is a powerful stimulation for growth hormone (GH) secretion in health. A standardised exercise test can, therefore, be discriminative for the diagnosis of GH-deficiency in adults. This will be assessed. Hypothesis (ectopic fat stores)

1. 1.Ectopic fats stores are flexible fuel stores and are influenced by diet and physical activity.FFA availability may play an important regulatory role.
2. 2.There is a tissue specific partitioning of triglycerides and/or FFA among non-adipose organs after fat load and physical exercise
3. 3.The flexibility of ectopic fat stores is related to insulin sensitivity
4. 4.Lipolytic and anti-lipolytic hormones are critical for regulating FFA availability (at rest or during exercise) and therefore also for the regulation of ectopic fat stores.
5. 5.GH is a lipolytica hormone. Lack of GH in adulthood is related to decreased FFA availability thereby influencing ectopic lipid stores Hypothesis diagnosis of GHD
6. 6.A short intensive physical exercise shows a good discriminative power to diagnose GHD.

Conditions

Ectopic Lipids; Insulin Sensitivity; Aerobic Exercise; Fat Load; Growth Hormone Deficiency

Outcome Measures

Primary Outcomes (1)

• Flexibility of IMCaL, IMCL and IHCL (fat load and exercise)

  Year 1 to 4

Secondary Outcomes (3)

• Determination of visceral fat mass by MRI

  Year 1 to 4

• Determination of peripheral and hepatic insulin sensitivity by two step hyperinsulinemic euglycemic clamp

  Year 1 to 3

• maximal exercise capacity

  Year 1 to 3

Study Arms (3)

1

Endurance trained athletes: minimal \>50 mlO2/KG body weight

2

Sedentary healthy control subjects: age, BMI, Gender and waist matched (to the growth hormone deficient patients)

3

GHD patients without a GH substitution therapy in the last 6 months

Dietary Supplement: Fat diet; Other: 2h standardized aerobic exercise

Interventions

Fat diet DIETARY_SUPPLEMENT

Instructions for a high fat diet will be given at the end of visit 2. This consists of the usual food intake with a supplementary fat intake of 0.75g fat/kg BW, administered as 3 additional snacks. These snacks will be distributed in pre-packed bags. A food diary will be kept. All arms will receive this diet during the 3 days preceding the clamp.

3

2h standardized aerobic exercise OTHER

Aerobic (50-60% of Vo2 max) standardized exercise on a bicycle during 2 hours

3

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Athletes:Endurance trained athletes: minimal \>50 mlO2/KG body weight GH-deficient adult patients: NO GH-replacement therapy during the last 6 months Sedentary controls: age, BMI, Gender and waist matched (to the growth hormone deficient patients) healthy control subjects

You may qualify if:

• Male and female patients \>18 years old
• Capable to exercise for 120 minutes on a treadmill
• Willingness to participate in the study and to give written consent.
• Normal ECG during ergometry
• Specific for Athletes: VO2max\> 50 ml/kg/min
• Specific for GHD patients: no GH substitution in the last 6 months
• Specific for sedentary controls: Matched the GHD patients for age, gender, BMI and waist

You may not qualify if:

• Abnormal liver or renal function
• Active neoplasia
• Severe cardiovascular disease (unstable coronary artery disease, heart failure NYHA III-IV)
• Haemophilia
• Inability to exercise
• Contraindications to exposure to a 3 T magnetic field
• Abnormal ECG during ergometry
• Women in childbearing age unless on a continuous contraceptive therapy or surgically sterilized
• Depression, psychosis and other severe personality disorders
• Pregnant women
• Excessive alcohol consumption (\>60g/d) or drug abuse

Sponsors & Collaborators

• Insel Gruppe AG, University Hospital Bern: lead
• Swiss National Science Foundation: collaborator

Study Sites (1)

Department of Endocrinology, Diabetes and Clinical Nutrition, University Hospital Bern

Bern, 3010, Switzerland

Location

Related Publications (2)

• Zueger T, Alleman S, Christ ER, Stettler C. Exercise-induced GH secretion in the assessment of GH deficiency in adult individuals. Eur J Endocrinol. 2011 Nov;165(5):723-8. doi: 10.1530/EJE-11-0539. Epub 2011 Aug 19.

  PMID: 21856788 RESULT

• Loher H, Jenni S, Bucher J, Krusi M, Kreis R, Boesch C, Christ E. Impaired repletion of intramyocellular lipids in patients with growth hormone deficiency after a bout of aerobic exercise. Growth Horm IGF Res. 2018 Oct-Dec;42-43:32-39. doi: 10.1016/j.ghir.2018.08.001. Epub 2018 Aug 17.

  PMID: 30153529 DERIVED

MeSH Terms

Conditions

Insulin Resistance; Dwarfism, Pituitary

Condition Hierarchy (Ancestors)

Hyperinsulinism; Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Dwarfism; Bone Diseases, Developmental; Bone Diseases; Musculoskeletal Diseases; Bone Diseases, Endocrine; Hypopituitarism; Pituitary Diseases; Hypothalamic Diseases; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Endocrine System Diseases

Study Officials

• Emanuel Christ, Prof. Dr med. MD, PhD

  Division of Endocrinology, Diabetes and Clinical Nutrition, University Hospital Bern

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER

Study Record Dates

• First Submitted: November 3, 2011
• First Posted: November 8, 2011
• Study Start: August 1, 2011
• Primary Completion: May 1, 2014
• Study Completion: May 1, 2014
• Last Updated: October 9, 2018

Record last verified: 2018-10

Locations

CH (1)