The Woolcock Institute of Medical Research

Every day, our lungs perform a remarkable balancing act. With every breath, they are exposed to airborne particles and environmental challenges, yet they continuously repair and renew themselves to keep us breathing.

As we age, however, this repair capacity gradually declines. Understanding why this happens is an important area of respiratory research, as ageing is one of the strongest risk factors for chronic lung diseases including chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF).

Dr Jiahui Zhu, a respiratory doctor and researcher from China working within the Woolcock’s Respiratory Cellular and Molecular Biology research group, is exploring the question of why ageing lungs lose some of their ability to heal.

“Our lungs are constantly exposed to viruses, pollution, cigarette smoke and countless airborne particles,” she explains. “They quietly repair this everyday damage, allowing us to breathe normally without even noticing. As we grow older, however, this remarkable ability begins to decline.”

Ageing is not simply a process where lung cells “wear out”. Instead, the complex systems responsible for maintaining and repairing lung tissue become less effective over time.

“One of the main reasons is that cells that help maintain the tiny air sacs of the lungs become less capable of replacing damaged tissue after injury. At the same time, immune cells such as macrophages are more likely to remain in a chronic, low-grade inflammatory state, creating an environment that interferes with normal healing rather than supporting it.”

“As a result, injuries that would once have healed completely may instead leave behind persistent inflammation or scar tissue. This helps explain why older adults often recover more slowly after respiratory infections.”

Understanding why lung repair declines with age has become a major focus of respiratory research. Scientists are now investigating how to restore the regenerative capacity of AT2 cells, reduce age-related inflammation and improve communication between immune cells and lung tissue. Rather than simply treating the consequences of lung disease, these approaches aim to strengthen the lungs' own ability to heal.

Dr Zhu’s work connects strongly with the Woolcock Centre for Chronic Diseases of Ageing’s (CCDA) mission to understand and address chronic health conditions that become more common as people grow older.

Established in July 2022, the CCDA brings together expertise in respiratory and sleep research to investigate conditions including COPD, emphysema and sleep disorders, as well as their links to cognitive decline and neurodegenerative diseases such as dementia.

The Centre’s researchers are working to uncover earlier ways of detecting age-related disease, develop innovative treatments and translate discoveries into improved clinical care. By combining expertise across lung physiology, cell biology, respiratory technology, sleep science, clinical management, epidemiology and data science, the CCDA aims to improve health outcomes for an ageing population.

Healthy ageing is not just about preventing damage — it is also about preserving the body's natural capacity to repair itself. Through research into the biology of ageing lungs, scientists like Dr Zhu are helping to reveal the mechanisms that influence healthy ageing and opening new possibilities for therapies that allow people to maintain stronger, healthier lungs for longer.

Find out more

• Our Respiratory Cellular and Molecular Biology research group
• The Woolcock Centre for Chronic Diseases of Ageing