Cichorium intybus Linn. Extract Prevents Type 2 Diabetes Through Inhibition of NLRP3 Inflammasome Activation

This study provides the scientific basis for the inhibitory effect of the aerial parts of Cichorium intybus Linn. (C. intybus) on the activation of the NLRP3 inflammasome in vitro and on high-fat diet (HFD)-induced type-2 diabetes (T2D). Lipopolysaccharide (LPS)-primed bone marrow-derived macrophages were used to study the effects methanolic extract of C. intybus leaf (CI) on inflammasome activation. An insulin resistance model (mice fed a HFD) was used to study the in vivo effect of CI on T2D. CI attenuated interleukin-1 beta (IL-1 beta) secretion by inhibiting the activation of the NLRP3 inflammasome in mouse bone marrow macrophages. The CI treatment attenuated the intracellular movement of NLRP3 in Triton X-100 insoluble fraction, without affecting the expression of other NLRP3 inflammasome-related proteins. Attenuated IL-1 beta secretion may improve glucose metabolism in the HFD-fed insulin resistance mouse model. CI also attenuated the infiltration of M1 macrophages and increased the M2 macrophage population in white adipose tissue. Collectively, our data showed that CI inhibits IL-1 beta secretion through attenuation of NLRP3 inflammasome activation, leading to an antidiabetic effect by improving glucose metabolism and inhibiting metainflammation.