Chlojaponilactone B Attenuates THP-1 Macrophage Pyroptosis by Inhibiting the TLR/MyD88/NF-κB Pathway.

Pyroptosis, an innate immune response, plays a crucial role in the pathological process of inflammatory diseases. Although pyroptosis blockade is considered a potential therapeutic strategy, no ideal candidate drug has been identified. The natural product Chojaponilactone B (CJB) has demonstrated anti-inflammatory effects, but its role in macrophage pyroptosis has not been studied. This study aimed to investigate the effect and mechanism of CJB in inhibiting macrophage pyroptosis. Using an LPS/ATP-induced THP-1 macrophage pyroptosis model, we found that CJB significantly inhibited pyroptosis and reduced the levels of NLRP3, caspase 1, N-GSDMD, and inflammatory cytokines IL-1ß and IL-18. RNA sequencing analysis revealed that CJB interfered with LPS/ATP-induced THP-1 macrophage gene expression, suggesting involvement in anti-inflammatory and anti-pyroptotic signaling pathways. Additionally, CJB suppressed LPS/ATP-induced elevations in TLRs, MyD88, pro-IL-1ß, and NF-κB and blocked NF-κB p65 nuclear translocation. In summary, CJB inhibits NLRP3 activation and macrophage pyroptosis through the TLR/MyD88/NF-κB pathway, providing important evidence for its development as a potential drug for treating pyroptosis-related inflammatory diseases.

(±)-Sarcanan A, a pair of new enantiomeric dihydrobenzofuran neolignans from the aerial parts of Sarcandra glabra.

(+)-Sarcanan A (1a) and (-)-Sarcanan A (1b), a pair of new dihydrobenzofuran neolignan enantiomers, together with six known compounds (2-7), were isolated from the aerial parts of Sarcandra glabra. Their structures were elucidated by spectroscopic analysis, and the absolute configurations of 1a and 1b were determined by analyses of the electronic circular dichroism (ECD) data. All compounds were evaluated for their inhibitory effects on the nitric oxide (NO) production induced by lipopolysaccharide (LPS) in RAW264.7 cells, and compounds 2-4 exhibited moderate inhibition against NO production.

Neuroprotective Effects of a New Derivative of Chlojaponilactone B against Oxidative Damaged Induced by Hydrogen Peroxide in PC12 Cells.

A new sesquiterpenoid (1) was obtained by hydrogenating Chlojaponilactone B. The structure of 1 was elucidated according to a combination of NMR, HRESIMS, and NOE diffraction data. The treatment of H2O2 in a PC12 cell model was used to evaluate the antioxidant activity of 1. An MMT assay showed that 1 had no cytotoxicity to the PC12 cell and rescued cell viability from the oxidative damage caused by H2O2. The treatment of 1 stabilized the mitochondria membrane potential (MMP), which decreased the intracellular ROS level and reduced cell apoptosis in the oxidative stress model. The activities of antioxidant enzyme superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and the content of intracellular glutathione (GSH) were significantly enhanced after the treatment of 1. In addition, the results of qRT-PCR showed that 1 treatment minimized the cell injury by H2O2 via the up-regulation of the expression of nuclear factor erythroid 2 (Nrf2) and its downstream enzymes Heme oxygenase 1 (HO-1), glutamate cysteine ligase-modifier subunit (GCLm), and NAD(P)H quinone dehydrogenase 1 (Nqo1). Based on the antioxidant activity of 1, we speculated its potential as a therapeutic agent for some diseases induced by oxidative damage.