Clinical Trial: IGF-I Stimulation of Collagen Synthesis in Ehlers-Danlos Patients

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: IGF-I Stimulation of Collagen Synthesis in Ehlers-Danlos Patients

Brief Summary:

The investigators want to inject insulin-like growth factor-I (IGF-I) into the patella tendon of Ehlers-Danlos patients and healthy controls to evaluate the response in collagen synthesis. Furthermore collagen synthesis is measured in muscle connective tissue and in skin.

The hypothesis is that the connective tissue in Ehlers-Danlos patients is more compliant and poorer in collagen than healthy controls, but that collagen synthesis can be stimulated by IGF-I.


Detailed Summary:

IGF-I will be injected with ultrasound guidance to one patella tendon and the other one will be injected with saline as control. Injections will be performed double blinded and timed 24 hours and 6 hours before tissue sampling.

Collagen synthesis will be measured as fractional synthesis rate based on stabile isotope technique using labelled proline.

10 patients diagnosed with Classical form of Ehlers-Danlos syndrome will be included and matched with 10 healthy controls based on age, gender, BMI and activity level.

The muscle biopsy will be taken from vastus lateralis muscle and the skin biopsy from the buttocks. The biopsies will if the size permits it also be used for histology and mRNA analyses.


Sponsor: Bispebjerg Hospital

Current Primary Outcome: Fractional synthesis rate of collagen in tendon, muscle and skin [ Time Frame: 6 hours ]

A flood primed infusion of proline labelled with a stable isotope is used to calculate fractional synthesis rate of collagen in the 3 types of tissues. The infusion continues for 6 hours and tissue sampling is performed afterwards.


Original Primary Outcome: Same as current

Current Secondary Outcome:

  • Electron microscopy
    If there is additional tissue in the biopsies a piece will be stored for electron microscopy. In skin and tendon a transverse slice will be evaluated on collagen fibril diameter, form and density. In muscle the amount and appearance of connective tissue will be studied.
  • mRNA
    From the muscle biopsy a piece will be stored for mRNA analysis if possible. Targets will be collagen types and IGF-I isoforms.


Original Secondary Outcome: Same as current

Information By: Bispebjerg Hospital

Dates:
Date Received: September 27, 2011
Date Started: September 2011
Date Completion:
Last Updated: November 19, 2012
Last Verified: November 2012