Confocal micrograph of mouse lungs loaded with drug-carrying microparticles (pink). Image credit: Gregory Szeto, Adelaide Tovar, Jeffrey Wyckoff, Koch Institute, MIT (CC BY-NC-ND)
Breathing is essential to life. At birth, the brain quickly adapts and learns to control breathing in different situations. This adaptability is called neuroplasticity. Most breathing-related adjustments in the brain are short-term, like breathing faster during exercise. The brain can also learn from prior experience to prepare for future situations. For example, intermittent exposure to low oxygen causes long-term changes in signals from the brain to muscles controlling breathing, which may help them prepare for future low oxygen situations. This is called long-term facilitation (LTF). This neuroplasticity may also help the brain to compensate or stabilize breathing during an illness or injury.
Illnesses shortly after birth can affect how the brain controls breathing and may contribute to respiratory diseases later in life. They may also have lasting effects on the ability to of the brain to learn and respond to stress, and may even contribute to psychiatric disorders or age-related cognitive decline.
Now, Hocker et al. show that inflammation shortly after birth has effects on breathing control that extend into adulthood. In the experiments, rats were injected four days after birth with either saline solution or a drug causing inflammation. When the rats grew into adults, their ability to make long-term breathing adjustments, or LTF, was assessed. In the rats exposed to early life inflammation two important pathways that enable LTF were eliminated. One pathway was restored when the rats received an anti-inflammatory treatment. Activating nerve cells reinstated the other pathway, suggesting these cells are not impaired.
The experiments suggest inflammation during early life impairs breathing control later on and may contribute to adult respiratory disease. Inflammation is common among infants in their first year, particularly among those born prematurely. This early-life inflammation may put them at risk of diseases associated with breathing control, like sleep apnoea, later in life. More studies are needed to understand the relationship between early life inflammation, respiratory control, and respiratory disease later in life.
