The immune response to resistive breathing: Implications for respiratory failure

Abstract

Resistive breathing is an “immune challenge” for the body, initiating an inflammatory response consisting of elevation of plasma cytokines and recruitment and activation of lymphocyte subpopulations. These cytokines do not originate from monocytes, but are instead produced within the diaphragm secondary to the increased muscle activation. Oxidative stress is a major stimulus for the cytokine induction secondary to resistive breathing. The production of cytokines within the diaphragm may be mediating the diaphragm muscle fiber injury that occurs with strenuous contractions, or contribute to the expected repair process. These cytokines may also compromise diaphragmatic contractility or contribute to the development of muscle cachexia. They may also have systemic effects, mobilizing glucose from the liver and free fatty acid from the adipose tissue to the strenuously working respiratory muscles. At the same time, they stimulate the hypothalamic-pituitary-adrenal (HPA) axis leading to production of adrenocort...