MCL Plays an Anti-Inflammatory Role in Mycobacterium tuberculosis-Induced Immune Response by Inhibiting NF-κB and NLRP3 Inflammasome Activation.

Mycobacterium tuberculosis (Mtb) remains a significant menace to global health as it induces granulomatous lung lesions and systemic inflammatory responses during active tuberculosis (TB). Micheliolide (MCL), a sesquiterpene lactone, was recently reported to have a function of relieving LPS-induced inflammatory response, but the regulative role of MCL on the immunopathology of TB still remains unknown. In this experiment, we examined the inhibitory effect of MCL on Mtb-induced inflammatory response in mouse macrophage-like cell line Raw264.7 by downregulating the activation of nuclear factor kappa B (NF-κB) and NLRP3 inflammasome. Evidences showed that MCL decreased the secretion of Mtb-induced inflammatory cytokines (IL-1ß and TNF-α) in a dose-dependent manner. Meanwhile, MCL dramatically suppressed Mtb-induced activation of iNOS and COX2 as well as subsequent production of NO. Furthermore, MCL inhibited Mtb-induced phosphorylation of Akt (Ser 473) in Raw264.7. According to our results, MCL plays an important role in modulating Mtb-induced inflammatory response through PI3K/Akt/NF-κB pathway and subsequently downregulating the activation of NLRP3 inflammasome. Therefore, MCL may represent as a potential drug candidate in the adjuvant treatment of TB by regulating host immune response.

[Effect of ditching for drain on control of Oncomelania hupensis snail in beaches of Dongting Lake].

OBJECTIVE: To evaluate the effect of ditching for drain on the control of the breed of Oncomelania hupensis snails in beaches of Dongting Lake. METHODS: From November, 2009 to November, 2012, an 0. hupensis snail infested beach of the Yueyang jail and an O. hupensis snail infested beach of Junshan District were selected as research fields in the eastern Dongting Lake area, and the former, as the intervention field, was performed with the ditching for drain by excavators and the latter, as the control field, was not. RESULTS: Before the project implemented, the average soil moisture contents on the beaches in dry seasons of the two fields were both about 35.56%. After the project implemented, in the intervention field, the average soil moisture content was 26.53% which was significantly lower than that (35.56%) in the control field (F = 6.53, P < 0.05). The underground water levels in different heights in the intervention field were lower than those in the control field (χ2 = 33.33, P < 0.05). Before the project implemented, the natural death rates of the snails were 0.98% and 0.89% in the two research fields respectively (P > 0.05), and after the project implemented (in 2012), no adult and young snails were found in the interventional field, but in the control field, the average densities of living snails and young snails were 29.37 snails/0.1 m2 and 213 ± 108.45 snails/0.1 m2 respectively. CONCLUSION: The intervention of ditching for drain can decrease the soil moisture contents quickly and change the ecological condition, therefore, can control the breed of O. hupensis snails in the beaches of Dongting Lake.