Researchers discover cause of pulmonary fibrosis

Good news for five million people world wide diagnosed with idiopathic pulmonary fibrosis.  Researchers now believe they have discovered the cause of the condition, and this may lead to potential treatments and possibly even a cure.

What has been known is that repeated exposure to various substances -- such as an infection, drugs, or inhaled chemicals -- may irritate the interstitium, or tissue that lines and supports the alveolar air sacs, causing it to become inflamed, and then increasingly scarred and thickened.  This makes it so oxygen is unable to diffuse across alveoilar-capillary membranes.  This results in progressively worsening and irreversible dyspnea.

Pink = Chromosome
Green = Telomeres

So, while normal air sacs are very elastic like balloons, expanding and contracting with each breath, a thickened interstitium makes it so they become stiffer and less elastic, therefore less able to expand and contract with each breath.

At the present time treatment is generally supportive, such as oxygen therapy and anxiolytics.

Researchers now believe that the causative agents may cause damage to telomeres that are present in every cell in the human body. Telomeres are the caps of DNA that protect our chromosome, like the plastic tips on the ends of shoelaces.  They prevent the strands of DNA, and therefore the cell, from breaking apart.  When they do break apart this in essence speeds up the aging process.

The researchers discovered that some mice lacked a protein necessary to build telomeres in a specific cell population.  By studying these mice, they learned that they develop progressively worsening pulmonary fibrosis similar as to what occurs in the human population.

They also learned that lack of telomeres is lethal to type II alveolar cells, making it so epithelial cells cannot regenerate and cannot repair damage.  This results in the natural breakdown (aging) of the cells causing them to become inflamed, resulting in increased scarring and thickening (fibrosis).

While this was only one research project, it should give something to focus on with the hopes of coming up with some form of treatment for this condition that is more than just supportive.

Further reading:

• What is pulmonary fibrosis?