A double-blind, randomized, placebo-controlled clinical trial on the effect of carvacrol on serum cytokine levels and pulmonary function tests in sulfur mustard induced lung injury

Abstract

ObjectiveThe aim of this study was to evaluate the effect of carvacrol on serum levels of interleukins (IL-2, IL-4, IL-6, IL-8, and IL-10), interferon-gamma (IFNγ) levels and pulmonary function tests (PFT) in patients who were exposed to sulfur mustard (SM). MethodsTwenty patients exposed to SM 27–30 years ago were divided to placebo and carvacrol (1.2 mg/kg/day) treated groups (n = 10 for each group). Drugs were given in a double-blind manner for two months. Serum levels of cytokines and PFT values including; maximum mid-expiratory flow (MMEF) and maximum expiratory flow at 25, 50 and 75% of vital capacity (MEF25, 50 and 75) were measured at the beginning (step 0), one and two month (steps I and II, respectively) after starting the treatment. ResultsThe serum levels of IL-2, IL-4, IL-6 and IL-8 were significantly decreased in step I and II compared to step 0 (p < 0.05 to p < 0.001), while the serum levels of IL-10 and IFNγ were increased in step II compared to step 0 (p < 0.01, for both cases) and IFN-γ/IL-4 ratio was enhanced in step II compared to step 0 (p < 0.001) in carvacrol treated group. MMEF, MEF75, and 50 values were significant increase in step I and II compared to step 0 (p < 0.05 to p < 0.001) in carvacrol treated group. ConclusionTreatment with carvacrol for two months reduced inflammatory cytokine, while increased anti-inflammatory cytokines and improved PFT tests in SM induced lung injury.