Objective To explore dose-dependent effect of moxa smoke inhalation on lung tissue structure and blood CD4+/CD8+ T cell ratio in rats and to provide a theoretical basis for moxibustion therapy safety in clinical practice.
Methods Forty clean-grade 2-month-old male Wistar rats were randomly divided into 4 groups (10 in each group): a normal control (in moxa smoke-free environment) and low, moderate, and high moxa smoke group (exposed to smoke from full-burning of 10, 25 and 70 grams moxa 2 hours a day continuously for 30 days). Microscopic examinations were performed to observe morphological changes in the rats′ lung tissues. CD4+ and CD8+ T lymphocytes in peripheral blood of the rats were detected with flow cytometry.
Results Obvious inflammatory reaction was observed only in lung tissues of the rats exposed to high moxa smoke. The percentage of CD8+ T lymphocytes in high moxa smoke exposure rats was 37.13 + 2.23%, significantly higher than that in normal control rats (34.45 + 5.14%), and in the rats with low (33.84 + 3.23% ) and moderate (34.19 + 4.27%) moxa smoke exposure (P < 0.05 for all). The CD4+/CD8+ T cell ratio (1.46 ± 0.29) in the rats with high moxa smoke exposure was significantly lower than that in normal control rats (1.53 + 0.43) and in the rats with low (1.55 + 0.37) and moderate moxa smoke exposure (1.58 + 0.41) (all P < 0.05).
Conclusion Moxa smoke has dose-dependent effect on lung tissue morphology and immune system in rats. Low and moderate concentrations of moxa smoke induce no significant damage in lung tissues but can improve immune function in rats.
DownLoad: