Fibrosis a New Pathological Actor in Adipose Tissue
Condition: Obesity; Metabolic Diseases; Fibrosis; Body Weight
MeSH terms: Metabolic Diseases; Fibrosis; Body Weight
Study type: Interventional

Summary: 
      Adipose tissue (AT) has specific alterations in obesity in particular increased fibrosis
      amount compared to lean subjects. Fibrosis amount measured by immunohistochemistry on adipose
      biopsies appears to to predict weight loss response after a bariatric surgery. Non invasive
      tools to measure fibrosis needs to be validated. The investigators primary aim is to validate
      a new device able to measure adipose tissue stiffness.

      Thus the investigators plan to compare the stiffness results obtained with the device to the
      quantification of fibrosis using immuno-chemistry in massively obese patient's candidates to
      a bariatric surgery.
    

Detailed description: 
      Adipose tissue (AT) has specific alterations in obesity that could link obesity to its
      comorbidities. In particular increased fibrosis abundance in AT has been observed in obese
      compared to lean subjects. The investigators previously observed that the amount of fibrosis
      in AT measured at baseline could predict surgery-induced weight loss. Patient with the higher
      amount of fibrosis at baseline were those who lost less fat mass one year after surgery.

      To date fibrosis can only be measured using by immunohistochemistry after surgical biopsy. To
      that prospect, non invasive tools need to be validated, in particular device able to measure
      adipose tissue stiffness. The investigators hypothesis is that this new device is as powerful
      as IHC-quantified fibrosis to predict surgery induced weight loss.

      To answer that question the investigators will evaluate adipose tissue stiffness with the
      device as well as quantify fibrosis using immuno-chemistry on AT biopsy in morbidly obese
      patients before and during the first year after a bariatric surgery.

      The first objective is to validate the investigators new device by comparing both invasive
      fibrosis measurement on adipose tissue and non invasive stiffness measure The investigators
      second objective is to assess whether the investigators device can predict weight loss repose
      after bariatric surgery.

      This project is based on a clinical protocol performed in massively obese subjects (BMI>40
      kg/m² or BMI>35kg/m² with comorbidities). The investigators will recruit 250 obese patients
      addressed for bariatric surgery (bypass, sleeve or gastric banding). Clinical phenotype,
      biochemical analysis, body composition, systemic inflammation, adipose tissue biopsy (to
      evaluate inflammation and fibrosis) will be assessed at baseline and 3 and 12 months after
      surgery. Also at baseline surgical sub cutaneous and omental adipose tissue (to evaluate
      inflammation and fibrosis) as well as liver biopsy (to score non alcoholic hepatitis) will be
      analysed. 50 non obese patients will serve as controls. Adipose tissue stiffness measured
      with the device as well as fibrosis quantification on subcutaneous and omental adipose tissue
      will be assessed at baseline during programmed non inflammatory abdominal surgery
      Associations between all clinical and biological parameters will be assessed at the different
      point of the follow up.

      More generally, this project might lead us to elucidate whether fibrosis in adipose tissue
      can predict surgery outcome in terms of weight loss and obesity related complications
      improvement. Also the investigators want to validate a new non invasive tool to measure
      adipose tissue fibrosis and check whether it can predict surgery outcomes.
    

Intervention name(s): biopsy
Intervention type(s): Procedure
Intervention description(s): adipose tissue biopsy (to evaluate inflammation and fibrosis)
Allocation: Non-Randomized
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Diagnostic
Keywords: Obesity; adipose tissue fibrosis; Adipose tissue inflammation; Low grade systemic inflammation; non invasive device; Bariatric surgery