The protective effects of ambroxol on radiation lung injury and influence on production of transforming growth factor β₁ and tumor necrosis factor α

The aim of this article was to investigate the effect of ambroxol on radiation lung injury and the expression of transforming growth factor β₁ (TGF-β₁), as well as tumor necrosis factor α (TNF-α) in plasma. Totally, 120 patients with locally advanced lung cancer in radiotherapy were randomized into treatment and control groups. Patients in the treatment group took ambroxol orally at a dosage of 90 mg, three times per day for 3 months from the beginning of radiotherapy. The expression of TGF-β₁ and TNF-α in plasma was analyzed. The clinical symptoms and lung diffusing capacity were monitored using high resolving power computed tomography. The level of TGF-β₁ in the control group was increased (11.8 ± 5.5 ng/ml), whereas in ambroxol-treated patients, the increase was not significant (5.6 ± 2.6 ng/ml, P < 0.001). Radiotherapy-induced elevation of TNF-α levels, seen in control patients, was also abolished after treatment with ambroxol (5.1 ± 1.0 vs. 2.4 ± 0.8 ng/ml, P < 0.001). In the treatment group, carbon monoxide diffusion capacity was not significantly decreased at 6, 12, and 18 months post-radiotherapy, compared with the control group (P < 0.05). Ambroxol decreased the expression of TGF-β₁ and TNF-α, and minimized the diminishment of lung diffusion capacity after radiotherapy.