Functional Two-Way Crosstalk Between Brain and Lung: The Brain–Lung Axis

Abstract

The brain has many connections with various organs. Recent advances have demonstrated the existence of a bidirectional central nervous system (CNS) and intestinal tract, that is, the brain-gut axis. Although studies have suggested that the brain and lung can communicate with each other through many pathways, whether there is a brain–lung axis remains still unknown. Based on previous findings, we put forward a hypothesis: there is a cross-talk between the central nervous system and the lung via neuroanatomical pathway, endocrine pathway, immune pathway, metabolites and microorganism pathway, gas pathway, that is, the brain–lung axis. Beyond the regulation of the physiological state in the body, bi-directional communication between the lung and the brain is associated with a variety of disease states, including lung diseases and CNS diseases. Exploring the brain–lung axis not only helps us to understand the development of the disease from different aspects, but also provides an important target for treatment strategies.

The Rostral Ventromedial and Lateral Medulla Are the Major Areas Responsive to Lung Cancer Progression among Brainstem Lung-Innervating Nuclei

“…In addition, we did not specifically identify which nuclei in the ventral medulla are more important for lung tumor progression, and the regulatory mechanisms of these nuclei on lung function have not been investigated. Previous studies have shown that the medullary vagal efferent nerves can participate in neuroimmunoregulation by releasing acetylcholine to peripheral lung tissue [ 18 ]; however, whether these neurotransmitters affect lung tumors remains to be verified.…”

“…A paper published in Nature in 2022 also revealed the existence of brain–lung axis and proposed that the imbalance of lung microbiota would significantly affect the autoimmune response of the central nervous system [ 17 ]. Among them, the brain–gut axis and the brain–lung axis are bidirectional pathways between the central nervous system and the periphery, involving the crosstalk of the neuroanatomical pathway, immune pathway, endocrine pathway, and microbial pathway [ 18 ]. The autonomic nervous system is a neuroanatomical pathway for two-way communication between the central and peripheral regions.…”

“…The information is integrated by the brain and then fed back to the peripheral tissues through the vagal efferent nerves, thereby achieving crosstalk between the brain and the lung. In addition to the neuroanatomical pathway, neuropeptides and other biomarkers are also recognized as important mediators of communication between the central nervous system and peripheral effector cells, and they constitute the neurochemical basis of central and peripheral information crosstalk [ 18 ]. In neurodegenerative diseases, we can improve prognosis by monitoring peripheral immune markers to detect related central system diseases early and establish personalized treatment plans [ 20 ].…”

Mapping brain endophenotypes associated with idiopathic pulmonary fibrosis genetic risk

“…There has been scattered evidence in the literature for brain-lung relationships, across the spectrum of respiratory disorders. 15 , 16 , 17 , 18 , 19 , 20 Pulmonary fibrosis in particular has been clinically associated with cognitive decline, 13 , 21 increased risk of neurodegenerative disorders, 14 , 21 cerebrovascular accidents, 22 and a high prevalence of anxiety (30–50%) and depression (about 20–30%). 23 However, the mechanisms linking IPF to brain changes and dysfunction are poorly understood and likely multifactorial; including either direct shared pathomechanisms that result in fibrosis and scar development in the lung and to altered brain development and accelerated neurodegeneration or indirect sequelae of brain injury resulting from fibrosis-associated hypoxic tissue damage.…”

Neurological Disorder after Severe Pneumonia is Associated with Translocation of Bacteria from Lung to Brain

“…Studies have shown that the brain and lung can communicate through a variety of ways, such as neuroanatomical pathway, endocrine pathway, and immune pathway etc. 11 The lung is an organ that contains microbiota 12 . The microbial community in the lung composes of about 140 distinct families, while most of their functions in healthy individuals are still unknown 12 .…”