Diaphragm structure and function in health and disease

Area of Science:

• Physiology
• Anatomy
• Exercise Science

Background:

• The diaphragm is the primary inspiratory muscle, crucial for supporting ventilation during physical activity.
• Diaphragm function can be compromised by aging, obesity, and respiratory diseases like emphysema, potentially leading to muscle failure.
• Emerging evidence suggests regional metabolic differences within the diaphragm may predispose certain areas to failure.

Purpose of the Study:

• To review regional differences in mechanical and metabolic activity within the diaphragm.
• To explore how diaphragm heterogeneities influence function in both healthy and diseased states.
• To address regional structure, mechanics, blood flow, microcirculation, nitric oxide influences, and protein plasticity.

Main Methods:

• Review of existing literature on diaphragm structure, mechanics, and metabolism.
• Synthesis of findings related to regional differences in diaphragm function.
• Identification of knowledge gaps and future research directions.

Main Results:

• The diaphragm exhibits regional variations in structure, mechanics, and blood flow.
• Nitric oxide plays a role in diaphragm vasoactivity and contractility.
• Metabolic and contractile protein plasticity differs across diaphragm regions.

Conclusions:

• Understanding regional diaphragm heterogeneities is key to comprehending its function in health and disease.
• Further research is needed to fully elucidate the implications of these regional differences for diaphragm performance and failure.
• This review highlights the complex interplay of mechanical, metabolic, and vascular factors influencing diaphragm integrity.