Zataria multiflora extract influenced asthmatic patients by improving respiratory symptoms, pulmonary function tests and lung inflammation

Abstract

Ethnopharmacological relevance: Anti-inflammatory and anti-oxidant effects of Zataria multiflora Boiss (Z. multiflora) were reported in previous studies which is using in traditional and modern medicine. This plant is traditional used as an anti-tussive agent and for the management of respiratory disorders.

Aim of the study: The preventive effect of the extract of leaves and stems of Z. multiflora on respiratory symptoms, pulmonary function tests, hematological indices, high sensitivity C-reactive protein (hs-CRP), level of interleukin-10 (IL-10) in the serum and supernatant of cultured peripheral blood mononuclear cells (PBMC) and gene expression of IL-10 in these cells in asthmatic patients was studied.

Materials and methods: 36 asthmatic patients in three groups (randomly divided) of placebo group (P), two groups treated with 5 and 10 mg/kg/day doses of Z. multiflora (Z5 and Z10) for two months completed the study. Drugs were administered double-blindly and different variables were assessed before and after (one and two months) starting treatment including respiratory symptoms, pulmonary function tests (PFT), hematological indices, hs-CRP, serum and supernatant levels as well as gene expression of IL-10.

Results: Two months treatment with Z5 and Z10 led to significant reduction of respiratory symptoms (p < 0.05 to p < 0.001). Pulmonary function test values in treated groups were also significantly increased two months after starting treatment (p < 0.05 to p < 0.001). Total WBC, monocytes and eosinophils were also decreased in treated groups with the extract at the end of study period (p < 0.05 to p < 0.01). Hemoglobin and hematocrit in Z10 treated group (p < 0.05 and p < 0.01, respectively) and mean corpuscular volume (MCV) in both treated groups (p < 0.05 to p < 0.01) were significantly reduced. In addition, the level of hs-CRP in both treated groups was significantly reduced after two months (p < 0.05 to p < 0.01). IL-10 concentration in Z10 treated group in supernatant of PBMC was also significantly enhanced (p < 0.01). All comparisons were made compared to the baseline (beginning of the treatment) values.

Conclusion: Z. multiflora improved respiratory symptoms and increased pulmonary function tests in asthmatic patients. In addition, the plant was effective in decrement of inflammatory cells and hs-CRP as well as enhanced IL-10. Therefore, the plant showed possible preventive therapeutic effect on asthma.

Keywords: Asthma; Hematologic indices; Inflammation; Pulmonary function tests; Respiratory symptoms; Zataria multiflora.