Pulmonary Fibrosis Study Points to Protective Effects of Vitamin D

In a new study, researchers demonstrated the protective effects of vitamin D in a mouse model of pulmonary fibrosis induced by the chemotherapeutic drug bleomycin. The research paper, entitled “Preventive effects of vitamin D treatment on bleomycin-induced pulmonary fibrosis,” was published in the Nature journal Scientific Reports.

Vitamin D, often found at low levels in pulmonary fibrosis patients, has been shown to regulate the fibrotic process and be a useful agent in the treatment of fibrosis in different organs, such as bone, kidney and liver. However, despite the theorized correlation between vitamin D deficiency and advanced lung disease, its protective effects on pulmonary fibrosis remains largely unexplored.

To better understand the possible role of vitamin D on the pathogenesis and treatment of idiopathic pulmonary fibrosis (IPF), the most common type of interstitial lung disease and one with a large unmet medical need, researchers investigated the cellular and structural changes induced by treatment with vitamin D in mice with bleomycin-induced pulmonary fibrosis.

The research team divided the animals into four groups: control, bleomycin, bleomycin + vitamin D, and vitamin D only. Histological observation of lung tissue on days 14, 21, and 28 post-treatment revealed that vitamin D could reduce pulmonary fibrosis when compared with the bleomycin group. Moreover, the number of inflammatory cells was also significantly decreased in the bleomycin + vitamin D mice group, and the vitamin was able to suppress the cellular structural changes caused by the drug, leading researchers to conclude that vitamin D is able to ameliorate the disease symptoms caused by bleomycin.

No potential severe side effects from vitamin D intoxication, such as body weight loss, were observed. Researchers also evaluated the effect of vitamin D in myofibroblasts, cells critical to the development of pulmonary fibrosis due to their pro-fibrotic activity, and found that vitamin D reduces these cells’ numbers.

Despite some study limitations, such as unexplored effects of bioavailability, toxicity and dosing, and the absence of identification of vitamin D’s molecular targets, researchers concluded that “vitamin D treatment attenuates pulmonary fibrosis and associated cellular and ultrastructural changes induced by bleomycin in mice. Further effort will be necessary to identify the mechanism(s) involved in vitamin D signaling and explore the possibility of using vitamin D for prevention of side effects in the chemotherapy.”