CASP1 and systemic lupus erythematosus: Moreover, procyanidin B2 inhibited NLRP3 inflammasome activation by decreasing the expression of NLRP3, ASC, and caspase-1, and also reduced the renal and serum levels of IL-1β and IL-18 in the MRL/lpr lupus mice [85], suggesting that procyanidin B2 played anti-inflammatory and LN-protective roles in SLE by suppressing NLRP3 inflammasome activation and the production of IL-1β and IL-18.