Dehydrocostus Lactone Suppresses Dextran Sulfate Sodium-Induced Colitis by Targeting the IKKα/β-NF-κB and Keap1-Nrf2 Signalling Pathways

Dehydrocostus Lactone Ameliorates LPS-Induced Acute Lung Injury by Inhibiting PFKFB3-Mediated Glycolysis

Acute lung injury (ALI) is a destructive respiratory disease characterized by alveolar structural destruction and excessive inflammation responses. Aerobic glycolysis of macrophages plays a crucial role in the pathophysiology of ALI. Previous studies have shown that the expression of the key rate-limiting enzyme 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) in inflammatory cells is significantly increased, which promotes an increase in the rate of glycolysis in inflammatory cells. However, little is known about the biological functions of PFKFB3 in macrophage inflammation and ALI. In this study, we identified that PFKFB3 is markedly increased in lipopolysaccharide (LPS)-induced ALI mice and macrophages. Knockdown of pfkfb3 attenuated LPS-induced glycolytic flux, decreased the release of pro-inflammatory cytokines, and inactivated NF-κB signaling pathway in macrophages. Subsequently, we found that dehydrocostus lactone (DL), a natural sesquiterpene lactone, significantly decreased both the mRNA and protein levels of PFKFB3. Furthermore, it reduced the release of inflammatory cytokines and inactivated NF-κB pathways in vitro. Accordingly, DL alleviated LPS-induced pulmonary edema and reduced the infiltration of inflammatory cells in mouse lung tissue. In summary, our study reveals the vital role of PFKFB3 in LPS-induced inflammation and discovers a novel molecular mechanism underlying DL's protective effects on ALI.

Dehydrocostus lactone inhibits Candida albicans growth and biofilm formation

Candida albicans infections are threatening public health but there are only several antifungal drugs available. This study was to assess the effects of dehydrocostus lactone (DL) on the Candida albicans growth and biofilms Microdilution assays revealed that DL inhibits a panel of standard Candida species, including C. albicans, as well as 9 C. albicans clinical isolates. The morphological transition of C. albicans in RPMI-1640 medium and the adhesion to polystyrene surfaces can also be decreased by DL treatment, as evidenced by microscopic, metabolic activity and colony forming unit (CFU) counting assays. The XTT assay and microscopy inspection demonstrated that DL can inhibit the biofilms of C. albicans. Confocal microscopy following propidium iodide (PI) staining and DCFH-DA staining after DL treatment revealed that DL can increase the membrane permeability and intracellular reactive oxygen species (ROS) production. N-acetyl-cysteine could mitigate the inhibitory effects of DL on growth, morphological transition and biofilm formation, further confirming that ROS production induced by DL contributes to its antifungal and antibiofilm effects. This study showed that DL demonstrated antifungal and antibiofilm activity against C. albicans. The antifungal mechanisms may involve membrane damage and ROS overproduction. This study shows the potential of DL to fight Candida infections.

Systematic Exploration of the Potential Material Basis and Molecular Mechanism of the Mongolian Medicine Shudage-4 in Attenuating Stress-Induced Gastric Ulcer in Rat

Shudage-4, an ancient and well-known formula in traditional Mongolian medicine comprising four different types of traditional Chinese medicine, is widely used in the treatment of gastric ulcers. However, the potential material basis and molecular mechanism of Shudage-4 in attenuating stress-induced gastric ulcers remain unclear. This study aimed to first explore the potential material basis and molecular mechanism of Shudage-4 in attenuating gastric ulcers in rats. The chemical constituents and transitional components in the blood of Shudage-4 were identified by ultra-performance liquid chromatography time-of-flight mass spectrometry (UPLC-TOF-MS). The rat gastric ulcer model was induced by water immersion restraint stress (WIRS). The ulcer damage to gastric tissue was measured at the gross anatomical level and pathological level by hematoxylin-eosin (HE) staining of gastric tissue. RNA sequencing of gastric tissue and plasma metabolomics were performed to analyze the mechanism of Shudage-4 against gastric ulcers. A Pearson correlation analysis was performed to explore the association between serum metabolites and gene expression of gastric tissue. A total of 30 chemical constituents were identified in Shudage-4 by UPLC-TOF-MS. Among 30 constituents, 13 transitional components in the blood were considered as the potential material basis. Shudage-4 treatment had a significant effect on WIRS-induced gastric ulcers in rats. HE staining of gastric tissue illustrated that WIRS-induced ulcer damage was suppressed by Shudage-4 treatment. RNA sequencing of gastric tissue showed that 282 reversed expression genes in gastric tissue were related to Shudage-4 treatment, and gene set enrichment analysis revealed that Shudage-4 treatment significantly inhibited gene set expression related to reactive oxygen species (ROS), which was also validated by detecting rat gastric tissue MDA, GSH, SOD, GSH-Px, and CAT activities. The plasma metabolomic data demonstrated that 23 significantly differential metabolites were closely associated with the Shudage-4 treatment. The further multiomics joint analysis found that significantly upregulated 5 plasma metabolites in Shudage-4-treated rats compared to model rats were negatively correlated with gene set expression related to ROS in gastric tissue. Shudage-4 alleviated WIRS-induced gastric ulcers by inhibiting ROS generation, which was achieved by regulating plasma metabolites level.

Effects of Medicinal Plants and Phytochemicals in Nrf2 Pathways during Inflammatory Bowel Diseases and Related Colorectal Cancer: A Comprehensive Review

Inflammatory bowel diseases (IBDs) are related to nuclear factor erythroid 2-related factor 2 (Nrf2) dysregulation. In vitro and in vivo studies using phytocompounds as modulators of the Nrf2 signaling in IBD have already been published. However, no existing review emphasizes the whole scenario for the potential of plants and phytocompounds as regulators of Nrf2 in IBD models and colitis-associated colorectal carcinogenesis. For these reasons, this study aimed to build a review that could fill this void. The PubMed, EMBASE, COCHRANE, and Google Scholar databases were searched. The literature review showed that medicinal plants and phytochemicals regulated the Nrf2 on IBD and IBD-associated colorectal cancer by amplifying the expression of the Nrf2-mediated phase II detoxifying enzymes and diminishing NF-κB-related inflammation. These effects improve the bowel environment, mucosal barrier, colon, and crypt disruption, reduce ulceration and microbial translocation, and consequently, reduce the disease activity index (DAI). Moreover, the modulation of Nrf2 can regulate various genes involved in cellular redox, protein degradation, DNA repair, xenobiotic metabolism, and apoptosis, contributing to the prevention of colorectal cancer.

Xue-Jie-San restricts ferroptosis in Crohn's disease via inhibiting FGL1/NF-κB/STAT3 positive feedback loop

Crohn's disease (CD) is an incurable inflammatory bowel disease due to unclear etiology and pathogenesis. Accumulating evidences have shown the harmful role of ferroptosis in CD onset and development. Additionally, fibrinogen-like protein 1 (FGL1) has been verified to be a potential therapeutic target of CD. Xue-Jie-San (XJS) is an effective prescription for treating CD. However, its therapeutic mechanism has not been fully elucidated. This study aimed to determine whether XJS alleviating CD via regulating ferroptosis and FGL1 expression. A colitis rat model was induced by 2,4,6-trinitrobenzene sulfonic acid and treated with XJS. The disease activity indices of the colitis rats were scored. Histopathological damage was assessed using HE staining. ELISA was performed to examine inflammatory cytokines. Transmission electron microscopy was utilized to observe ultrastructure changes in intestinal epithelial cells (IECs). Iron load was evaluated by examining iron concentrations, the expressions of FPN, FTH and FTL. Lipid peroxidation was investigated through detecting the levels of ROS, 4-HNE, MDA and PTGS2. Furthermore, the SLC7A11/GSH/GPX4 antioxidant system and FGL1/NF-κB/STAT3 signaling pathway were examined. The results showed that colitis was dramatically ameliorated in the XJS-treated rats as evidenced by relief of clinical symptoms and histopathological damages, downregulation of pro-inflammatory cytokines IL-6, IL-17 and TNF-α, and upregulation of anti-inflammatory cytokine IL-10. Furthermore, XJS administration led to ferroptosis inhibition in IECs by reducing iron overload and lipid peroxidation. Mechanistically, XJS enhanced the SLC7A11/GSH/GPX4 antioxidant system negatively regulated by the FGL1/NF-κB/STAT3 positive feedback loop. In conclusion, XJS might restrain ferroptosis in IECs to ameliorate experimental colitis by inhibition of FGL1/NF-κB/STAT3 positive feedback loop.

Dehydrocostus lactone ameliorates lipid accumulation, insulin resistance, and endoplasmic reticulum stress in palmitate-treated hepatocytes

Fatty liver disease is caused by lipid accumulation in the liver, insulin resistance (IR), reactive oxygen species (ROS), and endoplasmic reticulum (ER) stress. Dehydrocostus lactone (DHE) has anticancer, anti-inflammatory, and anti-ulcer effects. However, its effects on hepatic steatosis and IR remain unclear. In this study, we investigated whether DHE has antisteatotic effect on fatty liver in vitro. Hepatocytes HepG2 and SNU-449 cells were exposed to 0.25 mM palmitate (PA), and then antisteatotic effect was evaluated by treatment with 10 μM DHE. DHE treatment reduced lipid accumulation and lipogenesis factor protein levels, compared with PA-treated hepatocytes. DHE treatment also decreased gluconeogenesis marker expression and recovered IR in PA-treated hepatocytes, and promoted glucose uptake in PA-treated HepG2 cells. Additionally, the levels of ROS and ER stress factors in PA-treated HepG2 cells were reduced by DHE treatment, compared with PA-treated HepG2 cells. Overall, DHE decreased lipid accumulation and lipogenesis factors as well as recovered IR, gluconeogenesis, and glucose uptake by reducing ER stress and ROS levels in PA-treated hepatocytes. Thus, DHE is a potential antisteatotic agent.

Eupalinolide B attenuates lipopolysaccharide-induced acute lung injury through inhibition of NF-κB and MAPKs signaling by targeting TAK1 protein

Acute lung injury (ALI) is a life-threatening disease characterized by severe inflammatory response, which has no pharmacological therapy in clinic. In this study, we found that eupalinolide B (EB), a sesquiterpene lactone isolated from Eupatorium lindleyanum, significantly ameliorated lipopolysaccharide (LPS)-induced ALI in mice, which manifests as reduction in lung injury score, activity of myeloperoxidase, and release of cytokines interleukin (IL)-1β, IL-6, tumor necrosis factor-α (TNF-α), and monocyte chemoattractant protein-1 (MCP-1). In RAW264.7 murine macrophages, EB effectively inhibited LPS-induced production of nitric oxide (NO) and prostaglandin E2 (PGE₂) by down-regulating the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX2), respectively. Mechanistically, EB not only blocked LPS-induced phosphorylation of inhibitor of nuclear factor kappa B kinase-α/β (IKKα/β), phosphorylation and degradation of inhibitor of nuclear factor-kappa B alpha (IκBα), and phosphorylation and nuclear translocation of nuclear factor-kappa B (NF-κB) P65, but also suppressed LPS-induced phosphorylation of mitogen-activated protein kinases (MAPKs) in vitro or in vivo. Through cellular thermal shift assay and western blotting, EB was demonstrated to target and inactivate transforming growth factor β activated kinase-1 (TAK1), which is an important upstream kinase for the activation of NF-κB and MAPKs pathways. Additionally, EB-mediated actions were markedly abolished by dithiothreitol in LPS-exposed RAW264.7 cells, suggesting a crucial role of the α,γ-unsaturated lactone for the anti-inflammatory activity of EB. In conclusion, our findings showed that EB could effectively alleviate ALI in mice, and attenuate inflammatory response by inhibiting the activation of TAK1, and TAK1-mediated activation of NF-κB and MAPKs cascades.

Brevilin A Ameliorates Acute Lung Injury and Inflammation Through Inhibition of NF-κB Signaling via Targeting IKKα/β

Acute lung injury (ALI) is life-threatening disease characterized by uncontrolled inflammatory response. IKKα/β, the key kinases in the activation of NF-κB pathway, are implicated in inflammatory pulmonary injury, and represent attractive targets for ALI therapy. Brevilin A (BVA) is a sesquiterpene lactone from Centipeda minima, a Chinese herb used to treat inflammatory diseases. This study aims to investigate the inhibition of BVA on ALI, with focus on clarifying the molecular mechanisms involved in BVA-mediated anti-inflammatory activity in macrophages. Briefly, BVA significantly inhibited the production of NO and PGE₂ by suppressing iNOS and COX2 expression, and suppressed the mRNA expression of IL-1β, IL-6, and TNFα in LPS/IFNγ-stimulated RAW264.7 macrophages. The anti-inflammatory activity of BVA was further confirmed in LPS/IFNγ-stimulated BMDMs and TNFα/IFNγ-exposed RAW264.7 cells. In vivo, BVA effectively attenuated LPS-induced lung damage, inflammatory infiltration, and production of pro-inflammatory cytokines, including MPO, IL-1β, IL-6, TNFα, and PGE₂. Mechanistically, BVA could covalently bind to the cysteine 114 of IKKα/β, and effectively inhibiting the activity and function of IKKα/β, thereby resulting in the suppression of phosphorylation and degradation of IκBα and the subsequent activation of NF-κB signaling. Furthermore, pretreatment of DTT, a thiol ligand donor, significantly abolished BVA-mediated effects in LPS/IFNγ-stimulated RAW264.7 cells, suggesting the crucial role of the electrophilic α, β-unsaturated ketone of BVA on its anti-inflammatory activity. These results suggest that BVA ameliorates ALI through inhibition of NF-κB signaling via covalently targeting IKKα/β, raising the possibility that BVA could be effective in the treatment of ALI and other diseases harboring aberrant NF-κB signaling.