The marine Penicillium sp. GGF16-1-2 metabolite dicitrinone G inhibits pancreatic angiogenesis by regulating the activation of NLRP3 inflammasome.

Citrinin derivatives have been found to have various pharmacological activities, such as anti-inflammatory, anti-tumor, and antioxidant effects. Dicitrinone G (DG) was a new citrinin dimer isolated from marine-derived fungus Penicillium sp. GGF 16-1-2 which has potential activity. Here, we aim to investigate whether DG has anti-pancreatic cancer activity. In xenograft tumor model, 2 × 106 BXPC-3 cells were injected into the hind flank of NU/NU nude mice by subcutaneously for 2 weeks followed by treating with DG (0.25, 0.5, 1 mg/kg) and 5-FU (30 mg/kg) for 4 weeks. Tumor volume and weight were measured, and the expression of CD31, IL-18, NLRP3, and Caspase-1 in tumor tissue were detected. In vitro, HUVECs were treated with conditioned medium (CM) derived from BXPC-3 cells, the effects of DG on angiogenesis were detected by tube formation and western blot analysis. In vivo studies showed that the tumor growth and angiogenesis were greatly suppressed. The tumor weight inhibition rates of DG and 5-FU groups were about 42.36%, 38.94%, 43.80%, and 31.88%. Furthermore, the expression of CD31 and Caspase-1 were decreased. In vitro, CM derived from BXPC-3 cells which treated with DG could inhibit the tube formation and expression of pro-angiogenic NICD in HUVECs. Our study suggests that DG could suppress angiogenesis via the NLRP3/IL-18 pathway and may have the potential to inhibit tumor development.

Coupled process of in-situ sludge fermentation and riboflavin-mediated nitrogen removal for low carbon wastewater treatment.

Volatile fatty acid recovery from waste activated sludge (WAS) was highly suggested to supplement carbon source for nitrogen removal. However, it was not easy to separate them from the metabolites under the ex-situ fermentation. In this study, in-situ WAS fermentation combined in the denitrification system was established to treat low carbon wastewater (COD/TN = 4), and riboflavin was employed as a redox mediator. This coupled process could simultaneously enhance the WAS fermentation and nitrogen removal, and riboflavin could significantly enrich the fermentative bacteria (Firmicutes phylum), denitrifying bacteria (Denitratisoma genus) and related functional genes (narGHJI, napABC, nirKS, nosZ, norBC), generating more available carbon sources for efficient nitrogen removal. This resulted in the effluent TN (<15 mg/L) satisfying the required discharge standard in China. This study provided new insights into the efficient nitrogen removal from low carbon wastewater, realizing the carbon-neutral operation of new concept wastewater treatment plant in China.

Berberine alleviates NLRP3 inflammasome induced endothelial junction dysfunction through Ca2+ signalling in inflammatory vascular injury.

BACKGROUND: Berberine has received rising attention for its application in cardiovascular disease because of its relationship with inflammation. The endothelial NLRP3 inflammasome triggers inflammatory vascular injury which would lead to cardiovascular disease. Endothelial calcium signalling plays a crucial role in both the activation of NLRP3 inflammasome and endothelial cells dysfunction. However, the efficacy of BBR on the endothelial NLRP3 inflammasome in inflammatory vascular injury remains unknown. PURPOSE: In this study, we focused on the NLRP3 pathway to determine whether BBR regulates endothelial junction function in inflammatory vascular injury. METHODS: The integrity of the junction proteins VE-cadherin (VEC) and zonula occludens-1 (ZO-1) detected by immunofluorescence and immunoblotting was used to determine the therapeutic effect of BBR (50, 100, or 200 mg/kg/day) in LPS (100 µg/kg/day)-induced inflammatory vascular injury in mice and mouse microvascular endothelial cells (MECs) treated with LPS (1 µLPS ) and ATP (5 mM). Endothelial permeability was assessed by FITC-labelled dextran and trans-endothelial electrical resistance (TEER) in vitro. The assembly and activation of NLRP3 inflammasomes were detected by western blotting and immunofluorescence. Pharmacophore-based virtual molecular docking studies and calcium imaging analyses were used to determine the interaction of BBR with the ATP-gated Ca2+ channel P2X7R (purinergic P2X receptor 7) in the context of inflammatory vascular injury. RESULTS: BBR recovered the expression of ZO-1 and VEC and inhibited endothelial NLRP3 inflammasome activation in coronary microvascular endothelium and in MECs. These results suggested a crucial role of the NLRP3 inflammasome in BBR-regulated endothelial integrity. Further analysis demonstrated that BBR treatment suppressed the binding of TXNIP (thioredoxin interacting protein) with NLRP3. Intriguingly, eliminating extracellular Ca2+ showed a similar effect as BBR. Virtual docking analysis indicated that R574 of P2X7R is a potential target for BBR binding. Ca2+ imaging showed that BBR inhibited the Ca2+ influx in response to ATP, supporting the potential interaction of BBR with P2X7R. CONCLUSIONS: These findings suggest that BBR exhibits potential and specific therapeutic value by targeting calcium signals and the endothelial NLRP3 inflammasome in inflammatory vascular injury.