[Effect of Different Concentrations of Moxa-smoke on Lung Function and TNF-α and IL-1 β Levels in Serum and Lung Tissues in Normal Rats]

Abstract

Objective: To study the effect of moxa-smoke inhaling on the respiratory system, so as to provide experimental data and theoretical basis for evaluating the safety of moxa-smoke inhaling during moxibustion treatment.

Methods: A total of 48 SD rats were randomized into control, low, medium and high moxa-smoke-concentration groups (n＝12 in each group). The low, medium and high concentrations of smoke were controlled in (0.11±0.05) mg/m^3, (0.23±0.05) mg/m³ and (0.53±0.05) mg/m³ respectively in each of 3 glass boxes (with reference to the level of PM 2.5). The smoking was conducted 4 hours each time, twice a day for 100 days. The normal group did not receive any moxa-smoke inhaling. The histopathological changes of lung and bronchial tissues were detected by H．E. stainning, and the contents of TNF-α and IL-1 β of plasma, bronchoalveolar la-vage fluid (BALF) and lung tissue detected by ELISA. The levels of forced vital capacity (FVC), forced expiratory volume (FEV), FEV 0.3/FVC (0.3＝ the 0.3^rd second), maximal mid-expiratory flow rate(MMEF), peak expiratory flow(PEF) were detected by animal pulmonary function analysis system.

Results: After 100 days' moxa-smoke inhaling, the contents of TNF-α in the plasma, BALF and lung tissues and IL-1 β in the lung tissue of the low, medium and high concentration moxa-smoke groups, and IL-1 β in the plasma and BALF of the medium and high concentration groups were significantly increased relevant to the control group (P<0.05, P<0.01). H．E. stain showed various inflammatory changes in the lungs and trachea tissues, including obvious fusion of pulmonary alveoli, lymphocyte infiltration, increase of capillary permeability, red blood cell exudation, etc. in the high concentration group, these situations were milder in the medium concentration group and were not obvious in the low concentration group. Compared with the control group, there were no significant changes in the FVC, FEV, FEV 0.3/FVC, MMEF and PEF of lung function in the three concentration groups (P> 0.05)．.

Conclusion: Long term inhalation of high concentration of moxa-smoke may lead to inflammatory injury in the lung and bronchial tissues but has no significant effect on the respiratory function in rats. Nevertheless, a good air-ventilation during moxibustion in a treatment room is necessary.

Keywords: Inflammatory injury; Lung function; Moxa-smoke inhale; Moxibustion therapy; Respiratory system; Safety.