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Ethnopharmacological Relevance: Coix seed, the dry mature seed kernel of the gramineous plant coix (Coix lacryma-jobi L. var. ma-yuen Stapf), is widely consumed as a traditional Chinese medicine and functional food in China and South Korea. We have previously demonstrated the protective effect of coixol, a polyphenolic compound extracted from coix, against Toxoplasma gondii (T. gondii) infection-induced lung injury. However, the protective effect of coixol on hepatic injury induced by T. gondii infection have not yet been elucidated., Aim of the Study: This study explores the impact of coixol on T. gondii infection-induced liver injury and elucidates the underlying molecular mechanisms., Materials and Methods: Female BALB/c mice and Kupffer cells (KCs) were employed to establish an acute T. gondii infection model in vivo and an inflammation model in vitro. The study examined coixol's influence on the T. gondii-derived heat shock protein 70 (T.g.HSP70)/toll-like receptor 4 (TLR4)/nuclear factor (NF)-κB signaling pathway in T. gondii-infected liver macrophages. Furthermore, a co-culture system of KCs and NCTC-1469 hepatocytes was developed to observe the impact of liver macrophages infected with T. gondii on hepatocyte injury., Results: Coixol notably inhibited the proliferation of tachyzoites and the expression of T.g.HSP70 in mouse liver and KCs, and attenuated pathological liver injury. Moreover, coixol decreased the production of high mobility group box 1, tumor necrosis factor-α, and inducible nitric oxide synthase by suppressing the TLR4/NF-κB signaling pathway in vitro and in vivo. Coixol also mitigated KCs-mediated hepatocyte injury., Conclusions: Coixol protects against liver injury caused by T. gondii infection, potentially by diminishing hepatocyte injury through the suppression of the inflammatory cascade mediated by the T.g.HSP70/TLR4/NF-κB signaling pathway in KCs. These findings offer new perspectives for developing coixol as a lead compound for anti-T. gondii drugs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Inflammation is a potential factor in the pathophysiology of depression. A traditional Chinese herbal medicine, arctiin, and its aglycone, arctigenin, are the major bioactive components in Fructus arctii and exhibit neuroprotective and anti-inflammatory activities. Arctigenin has been reported to have antidepressant-like effects. However, the antidepressant-like effects of arctiin, its precursor, remain unknown. In this study, we investigated the antidepressant-like effects of arctiin and its underlying mechanisms by in vivo and in vitro experiments in mice. Our results showed that arctiin significantly attenuated sucrose consumption and increased the immobility time in tail suspension and forced swimming tests. Arctiin decreased neuronal damage in the prefrontal cortex (PFC) of the brain. Arctiin also attenuated the levels of three inflammatory mediators, indoleamine 2,3-dioxygenase, 5-hydroxytryptamine, and dopamine, that were elevated in the PFC or serum of chronic unpredictable mild stress (CUMS)-exposed mice. Arctiin reduced excessive activation of microglia and neuroinflammation by reducing high mobility group box 1 (HMGB1)/toll-like receptor 4 (TLR4)- and tumor necrosis factor-α (TNF-α)/TNF receptor 1 (TNFR1)-mediated nuclear factor-kappa B (NF-κB) activation in the PFC of CUMS-exposed mice and HMGB1- or TNF-α-stimulated primary cultured microglia. These findings demonstrate that arctiin ameliorates depression by inhibiting the activation of microglia and inflammation via the HMGB1/TLR4 and TNF-α/TNFR1 signaling pathways.

Convallatoxin (CNT) is a cardiac glycoside isolated from Adonis amurensis Regel et Radde and has both anti-inflammatory and anti-proliferative properties. In the present study, the anti-inflammatory mechanisms of action of CNT was investigated in vitro and in vivo. Stimulation of mouse macrophages with lipopolysaccharide induced secretion of proinflammatory cytokines via suppression of peroxisome proliferator-activated receptor gamma (PPARγ) and activation of nuclear factor-κB (NF-κB), two transcription factors implicated in many inflammatory diseases. Notably, the effects of lipopolysaccharide were reversed by concomitant treatment of macrophages with CNT. Knockdown of PPARγ by siRNA inhibited the effect of convallatoxin on NF-κB activation. Because these transcription factors play a role in the development of ulcerative colitis in humans, the mice with experimental colitis induced by dextran sodium sulfate (DSS) was employed. Indeed, concomitant treatment with CNT ameliorated DSS-induced colitis symptoms, tissue damage, inflammatory cell infiltration, and proinflammatory cytokine production in the colon, and also reversed the activation of NF-κB and suppression of PPARγ. Collectively, these data indicate that CNT ameliorates colitic inflammation via activation of PPARγ and suppression of NF-κB, and suggest that CNT may be a promising treatment for inflammatory bowel disease (IBD)., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) is a complex that regulates several hundreds of genes, including those involved in immunity and inflammation, survival, proliferation, and the negative feedback of NF-κB signaling. Chelidonine, a major bioactive, isoquinoline alkaloid ingredient in Chelidonium majus, exhibits antiinflammatory pharmacological properties. However, its antiinflammatory molecular mechanisms remain unclear. In this work, we explored the effect of chelidonine on TNF-induced NF-κB activation in HCT116 cells. We found chelidonine inhibited the phosphorylation and degradation of the inhibitor of NF-κB alpha and nuclear translocation of RELA. Furthermore, by inhibiting the activation of NF-κB, chelidonine downregulated target genes involved in inflammation, proliferation, and apoptosis. Chelidonine also inhibited mitogen-activated protein kinase pathway activation by blocking c-Jun N-terminal kinase and p38 phosphorylation. These results suggest that chelidonine may be a potential therapeutic agent against inflammatory diseases in which inhibition of NF-κB activity plays an important role., (Copyright © 2017 John Wiley & Sons, Ltd.)

Artemisinin, isolated from the Chinese plant Artemisia annua, has been used for many years to treat different forms of malarial parasites. In this study, we explored the anti-inflammatory activity of artemisinin and the underlying mechanism of this action. We demonstrated that the anti-inflammatory effects of artemisinin in TPA-induced skin inflammation in mice. Then the artemisinin significantly inhibited the expression of NF-κB reporter gene induced by TNF-α in a dose-dependent manner. Artemisinin also inhibited TNF-α induced phosphorylation and degradation of IκBα, p65 nuclear translocation. Artemisinin also has an impact on upstream signaling of IKK through the inhibition of expression of adaptor proteins, TNF receptor-associated factor 2 (TRAF2) and receptor interacting protein 1 (RIP1). Furthermore, pretreatment of cells with artemisinin prevented the TNF-α-induced expression of NF-κB target genes, such as anti-apoptosis (c-IAP1, Bcl-2, and FLIP), proliferation (COX-2, cyclinD1), invasion (MMP-9), angiogenesis (VEGF), and major inflammatory cytokines (TNF-α, iNOS, and MCP1). We also proved that artemisinin potentiated TNF-α-induced apoptosis. Moreover, artemisinin significantly impaired the ROS production and phosphorylation of p38 and ERK, but did not affect the phosphorylation of JNK. Taken together, artemisinin may be a potentially useful therapeutic agent for inflammatory-related diseases.

• Arctigenin ameliorates T. gondii infection-induced liver injury. • Arctigenin attenuates the overexpression of HMGB1 and iNOS. • Arctigenin down-regulates the TLR4/NF-κB signaling pathways. Toxoplasmosis is a parasitic zoonosis with the highest incidence in humans. Severe lesions due to acute toxoplasmosis have been recorded in the visceral organs including the liver, where hepatocytes and Kupffer cells are important innate immune cells. Arctigenin (AG) is a bioactive ingredient of Arctium lappa L. and increasing evidence suggests that AG exhibits anti-oxidant, anti-inflammatory and anti- Toxoplasma gondii (T. gondii) effects. However, the role of AG in acute liver damage induced by T. gondii infection remains unclear. In this study, we analyzed the effects of AG against T. gondii -induced liver damage by establishing an in vitro infection model using a murine liver cell line (NCTC-1469 cells) and an in vivo mouse model with acute T. gondii infection of virulent RH strain. In the current study, AG effectively attenuated hepatocytes apoptosis and inhibited the reproduction of T. gondii. The results of in vitro and in vivo studies showed that AG significantly reduced alanine aminotransferase/aspartate aminotransferase activities and lessened pathological damage of liver. Moreover, AG suppressed T. gondii -induced inducible nitric oxide synthase production. AG also attenuated liver inflammation by inhibiting T. gondii -induced activation of the high-mobility group box1/toll-like receptor 4/nuclear factor-kappa B (HMGB1/TLR4/NF-κB) signaling pathway. These findings demonstrated that AG exhibited prominent hepatoprotective activities in toxoplasmic liver injury with anti-inflammatory effects by inhibiting the HMGB1/TLR4/NF-κB signaling axis. Thus, this study provides the basis for the development of new drugs to treat toxoplasmic hepatitis. [ABSTRACT FROM AUTHOR]