Americanin B inhibits pyroptosis in lipopolysaccharide-induced septic encephalopathy mice through targeting NLRP3 protein.

BACKGROUND: Sepsis is considered as a severe illness due to its high mortality. Sepsis can cause septic encephalopathy, thus leading to brain injury, behavioral and cognitive dysfunction. Pyroptosis is a type of regulated cell death (RCD) and takes a crucial part in occurrence and development of sepsis. Americanin B (AMEB) is a lignan compounds, which is extracted from Vernicia fordii. In our previous study, AMEB could inhibit microglial activation in inflammatory cell model. However, the function of AMEB in septic encephalopathy mice is uncertain. It would be worthwhile to ascertain the role and mechanism of AMEB in sepsis. PURPOSE: Current study designs to certify the relationship between pyroptosis and septic encephalopathy, and investigate whether AMEB can restrain NOD-like receptor pyrin domain-containing 3 (NLRP3) inflammasome activation and restrict pyroptosis by targeting NLRP3 in septic mice model. STUDY DESIGN: C57BL/6 mice were utilized to perform sepsis model in vivo experiments. BV-2 cell lines were used for in vitro experiments. METHODS: In vivo sepsis model was established by lipopolysaccharide (LPS) intraperitoneal injection in male C57BL/6 J mice and in vitro model was exposed by LPS plus ATP in BV-2 cells. The survival rate was monitored on the corresponding days. NLRP3, apoptosis associated Speck-like protein (ASC), caspase-1, GasderminD (GSDMD), interleukin-1ß (IL-1ß) and interleukin-18 (IL-18) level were detected by western blotting and immunofluorescence analysis. Molecular docking, cellular thermal shift assay (CETSA), drug affinity responsive target stability (DARTS) experiments, RNAi transfection and quantitative real-time PCR were applied to confirm the potential target of AMEB. RESULTS: The results suggested that AMEB could rise survival percentage and lighten brain injury in LPS-induced sepsis mice. In addition, AMEB could inhibit pyroptosis and the activiation of NLRP3 inflammasome. The inhibiting function of AMEB on the activiation of NLRP3 inflammasome is weakened following si-NLRP3 transfection. Moreover, AMEB exerted anti-pyroptosis effect via targeting NLRP3 protein. CONCLUSIONS: Our findings first indicate NLRP3 is an effective druggable target for septic encephalopathy related brain injury, and also provide a candidate-AMEB for the treatment of septic encephalopathy. These emerging findings on AMEB in models of sepsis suggest an innovative approach that may be beneficial in the prevention of septic encephalopathy.

Effect of NLRP3 Inflammasomes on Development of Diabetes Mellitus and Its Complications and Chinese Medicine Intervention via NLRP3： A Review / 中国实验方剂学杂志

Diabetes mellitus （DM） is a metabolic disease mainly characterized by chronic hyperglycemia and has multiple etiologies. The complications of DM， such as coronary atherosclerosis， nephropathy， foot disease and cardiac dysfunction， have high morbidity， disability rate and mortality. DM and its complications have a long course of disease and are easy to relapse， which are difficult to be cured， seriously affecting people's life and health. NOD-like receptor pyrin domain-containing 3 （NLRP3） inflammasome is an important component of inflammatory response and innate immune system. The inflammatory cascade induced by NLRP3 activation is involved in the occurrence and development of DM as well as its complications by releasing inflammatory factors， damaging endothelial cells and affecting metabolic stress. Therefore， as the core of the inflammatory response， NLRP3 may provide a new target for the treatment of DM and its complications. Traditional Chinese medicine plays a key role in the treatment of DM and its complications， and has a regulatory effect on NLRP3. Thus it has become a novel research strategy to prevent and treat DM and its complications via modulating NLRP3. However， at present， there are relatively scattered reports and a lack of systematic review on the role of traditional Chinese medicine in the treatment of DM and its complications from the perspective of NLRP3. As a result， this paper reviewed domestic and foreign literature in recent years and conducted the discussion from two aspects： the influence of NLRP3 on the occurrence and development of DM and its complications， and the progress of traditional Chinese medicine in intervening in DM and its complications through NLRP3. This paper provided reference for the research on the regulation of NLRP3 and a new direction for the treatment of DM and its complications.

Ω-3 fatty acids-supplementary in gestation alleviates neuroinflammation and modulates neurochemistry in rats.

BACKGROUND: The mechanisms underlying the association between immune activation and postpartum depression remained elusive. Although Ω-3 fatty acids possess anti-inflammatory properties, there is limited evidence directly linking the modulating effects of Ω-3 fatty acids on neuroimmune and neurochemistry to the antidepressant actions. METHODS: A between-groups design was used to assess the effects of reproductive status (virgin or parous) and Ω-3 fatty acids content (control and supplementary). Serum inflammatory cytokine levels (IL-1a, IL-1ß, IL-2, IL-6, IL-12, TNF-a, IFN-γ) were evaluated using the Bio-Plex Luminex System. Moreover, we also measured the protein levels of Purinergic type 2X7 receptor (P2X7R), NOD-like receptor pyrin domain containing 3 (NLRP3) and Nuclear factor-kappaB (NF-κB). Lastly, we assessed the function of various neurotransmitter systems to link the inflammatory response and neurotransmitter metabolism. RESULTS: Pro-inflammatory cyrokines, including IL-1a, IL-6, TNF-a and IFN-γ were markedly induced in the serum of parous rats, although no significantly depressive-like behavior was found. Meanwhile, NLRP3 and NF-κB were decreased in certain brain areas. Moreover, gestational stress significantly induced neurochemical disturbance, which is partly restored by Ω-3 fatty acids supplementation. CONCLUSIONS: These findings strengthen the link between inflammation, neurochemistry and postpartum depression, and further provide novel insights into the antidepressant effect of Ω-3 fatty acids.