OBJECTIVETo explore the mechanism of natural moxibustion on regulating immune imbalance in asthma rats.

METHODSSeventy SD male rats were divided into a normal group, a placebo group, a dexamethasone group, a big-cake for long-course moxibustion group, a big-cake for short-course moxibustion group, a small-cake for long-course moxibustion group and a small-cake for short-course moxibustion group, ten rats in each one. The rat model of asthma was established by egg albumen sensitization and stimulation in all the groups except the normal group. The natural moxibustion was used in all moxibustion groups, in which big cake of 1 cmX 1 cm size was used in the big-cake groups and small cake of 0.5 cmX 0. 5 cm size was used in the small cake groups. According to relevant acupoints, the natural moxibustion was performed, 5 h per time, once a day. Four times of treatment was considered one course, and three courses were required in the long-course groups and one course was required in the short-course groups. Intraperitoneal injection of dexamethasone was applied in the dexamethasone group, which had the same course as long-course moxibustion group. After the treatment, changes of EOS in peripheral blood of asthma rats were observed; enzyme linked immunosorbent assay (ELISA) was applied to test the contents of IgE, IL-4 and IFN-gamma in the lung tissue; real-time Q-PCR method was adopted to measure the expression level of transcription factor T-bet and GATA binding protein 3 (GATA-3) in the lung tissue.

RESULTSCompared with the normal group, the EOS in whole blood as well as IL-4 and IgE in plasma were all increased in the placebo group (all P< 0. 01), IFN-gamma in plasma was obviously decreased (P<0. 01); while the levels of EOS, IgE and IL-4 were significantly reduced (all P<0. 01), the content of IFN-gamma was increased (P<0. 01) in all moxibustion groups and dexametnasone group. Compared with the normal group, the expression of T-bet mRNA in the placebo group was significantly reduced (P<0. 01). Each treatment group could significantly increase the expression of T-bet mRNA and reduce that of GATA-3 mRNA (P<0. 01). Compared with the short-course moxibustion groups, the expression of T-bet mRNA was obviously increased in the long-course moxibustion group and dexamethasone group (both P<0.01), and that of GATA-3 mRNA was reduced (P<0.01). There was no significant difference between long-course moxibustion group and dexamethasone group (P> 0. 05), and also no significant difference could be seen between big-cake moxibustion group and small-cake moxibustion group (P>0. 05).

CONCLUSIONThe natural moxibustion could obviously reduce airway inflammation in asthma rats. With time passing, the efficacy is enhanced, indicating evident timeliness, which has no apparent relationship with the size of moxibustion cake.