Related Experiment Video
Updated: Jul 7, 2026

The Colon-26 Carcinoma Tumor-bearing Mouse as a Model for the Study of Cancer Cachexia
Published on: November 30, 2016
Possible mechanisms underlying the development of cachexia in COPD
1Division of Physiology, Dept of Medicine, University of California, San Diego, 9500 Gilman Drive, DEPT 0623A, La Jolla, CA 92093-0623A, USA. pdwagner@ucsd.edu
Abstract:
About 25% of patients with chronic obstructive pulmonary disease (COPD) will develop cachexia (fat-free body mass index <17 kg.m(-2) (males) or <14 kg.m(-2) (females)). This is associated with approximately 50% reduction in median survival. The pathogenetic mechanism has been variously suggested to result from the following: 1) energy imbalance; 2) disuse atrophy; 3) tissue hypoxia from arterial hypoxaemia; 4) systemic inflammation; and 5) anabolic hormonal insufficiency. Genetic polymorphisms implicate inflammatory cytokines, especially interleukin (IL)-1beta, but IL-6 and tumour necrosis factor (TNF)-alpha do not show polymorphisms in these patients. Early reports of elevated TNF-alpha levels suggested a role for inflammation, but recent studies have not shown elevated levels of either IL-6 or TNF-alpha. Therapeutic trials of nutritional support, hormonal supplementation, anti-TNF-alpha immunotherapy, ghrelin and antioxidants have been conducted, but only a few have shown any benefits in muscle structure and function. Considerably more mechanistic knowledge is needed before therapeutic recommendations can be made. At this time, it is not possible to attribute cachexia in COPD unequivocally to inflammation or any other cause, and much more research is needed. To date, studies have been predominantly cross-sectional, with measurements made only after cachexia has developed. Future research should target prospective observation, studying patients as cachexia progresses, since once cachexia is established, inflammatory cytokine levels may not be abnormal.
Related Concept Videos
Chronic Obstructive Pulmonary Disease-II: Pathophysiology
Chronic Inflammation
COPD: Pathogenesis and Clinical Features
The primary cause for the onset of COPD is cigarette smoking and exposure to air pollution. These hazardous factors initiate a chain reaction within the lungs, resulting in chronic inflammation, damage to the airways, and a...
Chronic Obstructive Pulmonary Disease III: Chronic Bronchitis Features
Chronic Obstructive Pulmonary Disease-III: Symptoms and Complications.
Symptoms of COPD can be classified as primary or systemic. Primary symptoms relate to reduced airflow, while systemic or extrapulmonary symptoms relate to COPD's broader impact on the body.
Primary Symptoms of COPD:
Chronic Obstructive Pulmonary Disease I: Introduction
Chronic Obstructive Pulmonary Disease
Smoking is a primary risk factor for COPD, with over 80% of patients having a history of it. Patients typically experience progressive dyspnea or labored breathing, frequent coughing, and recurrent pulmonary infections. Many eventually succumb to respiratory failure, characterized by...