Caffeine may have a protective effect against lung damage caused by prolonged oxygen therapy, according to a study in the American Journal of Physiology—Lung Cellular and Molecular Physiology.
The first-of-its-kind study evaluated the positive effects of caffeine on the minute tissue structures of the lungs. The findings could have implications in cases of oxygen supplementation administered to premature babies, as well as in other areas.
Long-term oxygen therapy can increase oxidative stress in the endoplasmic reticulum, a network of membranes involved in protein building. This increase can lead to inflammation and the formation of too few blood vessels and air sacs in the lungs.
Past research has shown that rodent pups exposed to hyperoxia develop lung changes similar to bronchopulmonary dysplasia (BPD) in extremely premature infants.
In this study, researchers at the Medical College of Wisconsin studied two groups of rat pups that were exposed to >90% oxygen to simulate the type of oxygen therapy typically encountered by premature newborns. One group was treated with caffeine injections, and one was not. The group that was exposed to normal room air was used as a control.
The high-oxygen group that did not receive caffeine had a significantly lower number of blood vessels present in the lungs, while the group receiving caffeine had an improved blood vessel count.
Researchers also found more new air sacs, less inflammation, and fewer markers of oxidative stress in the caffeine group. The endoplasmic reticulum in the cells lining the blood vessels in the lungs was wider than usual in the group that had high-oxygen without caffeine. This structural change, which is an indicator of increased stress, was not present in the caffeine group.
The study offers hope that treatment with caffeine can reduce stress and protect the blood vessels and air sacs of premature infants who rely on oxygen in their earliest days.