Micro-environment Involvement in Muscle Alteration Induced
Condition: Chronic Obstructive Pulmonary Disease; Exacerbations; Skeletal Muscle Atrophy
MeSH terms: Lung Diseases, Obstructive; Pulmonary Disease, Chronic Obstructive; Muscular Atrophy; Atrophy
Study type: Observational

Summary: 
      Chronic Obstructive Pulmonary Disease (COPD) is characterized by persistent airway
      obstruction and inflammatory response of the lungs and bronchi. Episodes of exacerbations
      contribute to increase the severity and prognosis of the disease. Muscle dysfunction (loss of
      strengh and muscle mass) is one of comorbidities affecting 30% to 60% of patients and playing
      a key role in their prognosis. During exacerbation, some studies have suggested an
      association between muscle dysfunction and modifications of inflammatory circulating factors
      such as CRP, TNF-alpha, IL- 6, IL8, but no exhaustive study has identified precisely one (or
      more) biomarker(s) that can induce this muscle wasting during the exacerbation of COPD. Our
      hypothesis is that the serum of exacerbated COPD patients represents a deleterious
      microenvironment for the muscle cells which would amplify the mechanisms of atrophy linked to
      hospitalization. Our team has already developed a cell culture model to study the effects of
      the plasma microenvironment on atrophy of cultured myotubes. The investigators have shown
      that the serum of COPD patients can induce muscle atrophy.

      The objectives of this study are : 1/ to evaluate the effects of circulating pro-inflammatory
      factors on atrophy and the myogenic capacities of muscle cells; and 2/ to identify one (or
      more) circulating biomarker (s) that may be responsible for the muscle damage induced by the
      microenvironment of hospitalized patients for exacerbation of COPD. First, myotubes and
      myoblasts of healthy subjects will be cultivated with 9 exacerbation copd patient serum or 9
      copd patient serum or 9 healthy subject serum. Myotube diameters, atrophy, inflammatory and
      oxidative stress markers and alteration of the myogenic capacity of satellite cells will be
      compared between three groups. Second, the differential expression of circulating
      proinflammatory molecules will be compared in the serum of the three groups. Identifying
      circulating factors associated with muscle weakness is a necessary step to better understand
      the mechanisms and consider a personalized therapeutic approach that can improve the
      functional and clinical prognosis of disease.

      .
    


Observational model: Other
Time perspective: Retrospective
Sampling method: Non-Probability Sample
Study population: 
        COPD patients hospitalized for exacerbation in Montpellier university hospital, France.

        COPD patients recruited in Clinique du Souffle, La Vallonie, Lodève, France. Healthy
        volunteer subject recruited in Clinique du Souffle, La Vallonie, Lodève, France.
      
Biospecimen description: 
      serum
    
Keywords: COPD Exacerbation; Muscle atrophy; Inflammation; Oxidative stress; Biomarkers