Sanguinarine promotes healthspan and innate immunity through a conserved mechanism of ROS-mediated PMK-1/SKN-1 activation

Patterns of pathogenesis in innate immunity: insights from C. elegans

The cells in barrier tissues can distinguish pathogenic from commensal bacteria and target inflammatory responses only in the context of infection. As such, these cells must be able to identify pathogen infection specifically and not just the presence of an infectious organism, because many innocuous bacteria express the ligands that activate innate immunity in other contexts. Unravelling the mechanisms that underly this specificity, however, is challenging. Free-living nematodes, such as Caenorhabditis elegans, are faced with a similar dilemma, as they live in microorganism-rich habitats and eat bacteria as their source of nutrition. Nematodes lost canonical mechanisms of pattern recognition during their evolution and have instead evolved mechanisms to identify specific ligands or symptoms in the host that indicate active infection with an infectious microorganism. Here we review how C. elegans surveys for these patterns of pathogenesis to activate innate immune defences. Collectively, this work demonstrates that using C. elegans as an experimental platform to study host-pathogen interactions at barrier surfaces reveals primordial and fundamentally important principles of innate immune sensing in the animal branch of the tree of life.

Asperuloside promotes innate immunity via IRE-1/XBP-1 mediated unfolded protein response

Numerous studies have reported that asperuloside (ASP), a monomeric compound extracted from the traditional Chinese medicine Spreading Hedyotis Herb, possesses a variety of medicinal properties, including the treatment of obesity, cancer, inflammatory diseases, and bacterial infections. However, its role in innate immunity and the underlying mechanisms of action remain largely unexplored. Protein homeostasis and the health of the endoplasmic reticulum (ER) are crucial for organismal function, as a well-balanced ER is essential not only for maintaining cellular integrity but also for ensuring immune homeostasis. In this study, we demonstrated that asperuloside enhances the resistance of Caenorhabditis elegans to the human opportunistic pathogen Pseudomonas aeruginosa PA14 and reduces the bacterial load within its intestine. Additionally, asperuloside promotes innate immunity by activating the IRE-1/XBP-1 signaling pathway. Furthermore, asperuloside protects A549 human lung epithelial cells and mice against PA14 infection through the IRE-1/XBP-1 signaling pathway. Our findings indicate that the ability of asperuloside to promote innate immunity is conserved across invertebrates and mammals, offering new insights for the future development of antibacterial drugs.

Exploring new drug treatment targets for immune related bone diseases using a multi omics joint analysis strategy

In the field of treatment and prevention of immune-related bone diseases, significant challenges persist, necessitating the urgent exploration of new and effective treatment methods. However, most existing Mendelian randomization (MR) studies are confined to a single analytical approach, which limits the comprehensive understanding of the pathogenesis and potential therapeutic targets of these diseases. In light of this, we propose the hypothesis that genetic variations in specific plasma proteins have a causal relationship with immune-related bone diseases through the MR mechanism, and that key therapeutic targets can be accurately identified using an integrated multi-omic analysis approach. This study comprehensively applied a variety of analytical methods. Firstly, the protein quantitative trait locus (pQTLs) data from two large plasma protein databases and the Genome-Wide Association Study (GWAS) data of nine immune-related bone diseases were used for Mendelian randomization (MR) analysis. At the same time, we employed the Summary-based Mendelian Randomization (SMR) method, combined with the Bayesian colocalization analysis method of coding genes, as well as the Linkage Disequilibrium Score Regression (LDSC) analysis method based on genetic correlation analysis, as methods to verify the genetic association between genes and complex diseases, thus comprehensively obtaining positive results. In addition, a Phenome-wide Association Study (PheWAS) was conducted on significantly positive genes, and their expression patterns in different tissues were also explored. Subsequently, we integrated Protein-Protein Interaction (PPI) network analysis, Gene Ontology (GO) analysis. Finally, based on the above analytical methods, drug prediction and molecular docking studies were carried out with the aim of accurately identifying key therapeutic targets. Through a comprehensive analysis using four methods, namely the Mendelian randomization (MR) analysis study, Summary-based Mendelian Randomization (SMR) analysis study, Bayesian colocalization analysis study, and Linkage Disequilibrium Score Regression (LDSC) analysis study. We found that through MR, SMR, and combined with Bayesian colocalization analysis, an association was found between rheumatoid arthritis (RA) and HDGF. Using the combination of MR and Bayesian colocalization analysis, as well as LDSC analysis, it was concluded that RA was related to CCL19 and TNFRSF14. Based on the methods of MR and Bayesian colocalization, an association was found between GPT and Crohn's disease-related arthritis, and associations were found between BTN1A1, EVI5, OGA, TNFRSF14 and multiple sclerosis (MS), and associations were found between ICAM5, CCDC50, IL17RD, UBLCP1 and psoriatic arthritis (PsA). Specifically, in the MR analysis of RA, HDGF (P_ivw = 0.0338, OR = 1.0373, 95%CI = 1.0028-1.0730), CCL19 (P_ivw = 0.0004, OR = 0.3885, 95%CI = 0.2299-0.6566), TNFRSF14 (P_ivw = 0.0007, OR = 0.6947, 95%CI = 0.5634-0.8566); in the MR analysis of MS, BTN1A1 (P_ivw = 0.0000, OR = 0.6101, 95%CI = 0.4813-0.7733), EVI5 (P_ivw = 0.0000, OR = 0.3032, 95%CI = 0.1981-0.4642), OGA (P_ivw = 0.0005, OR = 0.4599, 95%CI = 0.2966-0.7131), TNFRSF14 (P_ivw = 0.0002, OR = 0.4026, 95%CI = 0.2505-0.6471); in the MR analysis of PsA, ICAM5 (P_ivw = 0.0281, OR = 1.1742, 95%CI = 1.0174-1.3552), CCDC50 (P_ivw = 0.0092, OR = 0.7359, 95%CI = 0.5843-0.9269), IL17RD (P_ivw = 0.0006, OR = 0.7887, 95%CI = 0.6886-0.9034), UBLCP1 (P_ivw = 0.0021, OR = 0.6901, 95%CI = 0.5448-0.8741); in the MR analysis of Crohn's disease-related arthritis, GPT (P_ivw = 0.0006, OR = 0.0057, 95%CI = 0.0003-0.1111). In the Bayesian colocalization analysis of RA, HDGF (H4 = 0.8426), CCL19 (H4 = 0.9762), TNFRSF14 (H4 = 0.8016); in the Bayesian colocalization analysis of MS, BTN1A1 (H4 = 0.7660), EVI5 (H4 = 0.9800), OGA (H4 = 0.8569), TNFRSF14 (H4 = 0.8904); in the Bayesian colocalization analysis of PsA, ICAM5 (H4 = 0.9476), CCDC50 (H4 = 0.9091), IL17RD (H4 = 0.9301), UBLCP1 (H4 = 0.8862); in the Bayesian colocalization analysis of Crohn's disease-related arthritis, GPT (H4 = 0.8126). In the SMR analysis of RA, HDGF (p_SMR = 0.0338, p_HEIDI = 0.0628). In the LDSC analysis of RA, CCL19 (P = 0.0000), TNFRSF14 (P = 0.0258). By comprehensively analyzing plasma proteomic and transcriptomic data, we successfully identified key therapeutic targets for various clinical subtypes of immune-associated bone diseases. Our findings indicate that the significant positive genes associated with RA include HDGF, CCL19, and TNFRSF14; the positive gene linked to Crohn-related arthropathy is GPT; for MS, the positive genes are BTN1A1, EVI5, OGA, and TNFRSF14; and for PsA, the positive genes are ICAM5, CCDC50, IL17RD, and UBLCP1. Through this comprehensive analytical approach, we have screened potential therapeutic targets for different clinical subtypes of immune-related bone diseases. This research not only enhances our understanding of the pathogenesis of these conditions but also provides a solid theoretical foundation for subsequent drug development and clinical treatment, with the potential to yield significant advancements in the management of patients with immune-related bone diseases.

Multi-omic biomarkers associated with multiple sclerosis: from Mendelian randomization to drug prediction

Currently, the treatment and prevention of multiple sclerosis (MS) continue to encounter significant challenges. Mendelian randomization (MR) analysis has emerged as a crucial research method in the pursuit of new therapeutic strategies. Accordingly, we hypothesize that there exists a causal association between genetic variants of specific plasma proteins and MS through MR mechanisms, and that key therapeutic targets can be precisely identified by integrating multi-omics analytical approaches. In this study, we developed a comprehensive analytical framework aimed at identifying and validating potential therapeutic targets for MS. The framework commenced with a two-sample Mendelian randomization (MR) study utilizing two large plasma protein quantitative trait locus (pQTL) datasets. Building on this foundation, we performed Bayesian co-localization analysis of coding genes, followed by a full phenotype-wide association study (PheWAS) on the co-positive genes identified through both analytical methods. This approach allowed us to explore the functions of key genes and the mechanisms of co-morbidity associated with the disease. Subsequently, we integrated protein-protein interaction (PPI) network analysis, gene ontology (GO) analysis, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis to facilitate drug prediction and molecular docking studies. This study conducted a systematic analysis between two large plasma pQTLs datasets and MS. In the MR analysis, the MR analysis of Icelandic plasma pQTLs and MS identified 88 positive plasma proteins, while the MR analysis of the UK Biobank database pQTLs and MS identified 122 positive plasma proteins. By comparison, uroporphyrinogen III synthase (UROS) and glutathione S-transferase theta 2B (GSTT2B) were found to be the positive proteins shared by the two datasets. After false discovery rate (FDR) correction, signal transducer and activator of transcription 3 (STAT3) was a significantly positive protein in the analysis of Icelandic plasma pQTLs. In the analysis of the UK Biobank database pQTLs, advanced glycosylation end product-specific receptor (AGER), allograft inflammatory factor 1 (AIF1), butyrophilin subfamily 1 member A1 (BTN1A1), cluster of differentiation 58 (CD58), desmoglein 4 (DSG4), ecotropic viral integration site 5 (EVI5), tumor necrosis factor (TNF), and tumor necrosis factor receptor superfamily member 14 (TNFRSF14) were significantly positive proteins. After Bonferroni correction, AGER, CD58, EVI5, and TNF remained significantly positive proteins in the analysis of the UK Biobank database pQTLs. In the Bayesian colocalization analysis, EVI5 (PPH4 = 0.9800), O-GlcNAcase (OGA) (PPH4 = 0.8569), and TNFRSF14 (PPH4 = 0.8904) were the common positive genes in the two analysis methods. In conclusion, EVI5, OGA, and TNFRSF14 may be potential therapeutic targets for MS. Through the comprehensive application of MR analysis and Bayesian colocalization analysis, we have successfully identified that EVI5, OGA, and TNFRSF14 may be key therapeutic targets for MS. These findings may provide a scientific basis for the development of novel immunotherapies, combination treatment regimens, or targeted intervention strategies.

The effect and mechanism of sanguinarine against PCV2 based on the analysis of network pharmacology and TMT quantitative proteomics

Porcine circovirus type 2 (PCV2) is highly prevalent in nature and serves as the primary pathogen responsible for porcine circovirus-associated disease (PCVD/PCVAD), posing a significant threat to pig production. Currently, vaccination alone could not provide the complete protection for PCV2 infection. The active ingredients of traditional Chinese medicine have shown a positive effect in combating viral infections. This study employed tandem mass tag (TMT) labeled proteomic analyses and network pharmacology to examine the effect and mechanism of sanguinarine against PCV2. IFIH1, IFITM1, p38α, and JNK were identified as the key targets of sanguinarine against PCV2 based on proteomics and network pharmacology. Using PCV2-infected PK-15 cells, it was discovered that sanguinarine inhibited the expression of the PCV2 CAP gene by upregulating IFIH1, thereby promoting STAT1 phosphorylation and activating MAVS expression. This, in turn, facilitated IRF3 phosphorylation, leading to increase IFITM1 expression. Simultaneously, sanguinarine suppressed the expression of the PCV2 CAP gene by inhibiting the expression of p38α, JNK, and p-JNK protein. In conclusion, the results of this study suggest that sanguinarine exerts anti-PCV2 effects through different targets and pathways, which lays the foundation for the subsequent development of new anti-PCV2 veterinary drugs.

Norharmane prevents muscle aging via activation of SKN-1/NRF2 stress response pathways

Sarcopenia, the age-related decline in muscle mass and function, is a significant contributor to increased frailty and mortality in the elderly. Currently, no FDA-approved treatment exists for sarcopenia. Here, we identified norharmane (NR), a β-carboline alkaloid, as a potential therapeutic agent for mitigating muscle aging. We aimed to determine the ability of NR to delay muscle aging in Caenorhabditis elegans (C. elegans), mouse, and muscle cells in mice and humans. NR treatment improved swimming ability and increased the maximum velocity in aged C. elegans. Transcriptomic analysis revealed that NR upregulated detoxification genes in C. elegans, including cytochrome P450, UGT, and GST enzymes. NR-induced benefits were dependent on the SKN-1/Nrf2 stress response pathway. In mammalian models, NR delayed cellular senescence in human skeletal muscle myoblasts and enhanced myogenesis in C2C12 cells and primary aged myoblasts. NR supplementation in aged mice prevented muscle loss, improved muscle function, and reduced markers of cellular senescence. We found that the p38 MAPK pathway mediated NR activation of Nrf2 by disrupting the Nrf2-Keap1 interaction. NR also improved oxygen consumption rates and promoted mitochondrial biogenesis. These findings suggest that NR is a promising candidate for preventing sarcopenia and improving muscle health.

Berberine hydrochloride enhances innate immunity to protect against pathogen infection via p38 MAPK pathway

The p38 MAPK pathway, an evolutionarily conserved mechanism, plays a crucial role in defending hosts against bacterial infections in both mammals and nematodes. Activating p38 MAPK signaling has been identified as a promising strategy to strengthen innate immunity and enhance resistance to pathogenic infections across various organisms.Berberine hydrochloride (BH), an isoquinoline alkaloid derived from Coptis, is known for its diverse biological activities, including anticancer, antibacterial, anti-inflammatory, lipid-lowering, and hepatoprotective effects. However, its impact on innate immunity and the associated molecular mechanisms remains unclear. In this study, we discovered that 10 μM Berberine hydrochloride enhanced resistance against both Gram-negative pathogens, such as Pseudomonas aeruginosa, Salmonella enterica and Gram-positive pathogen Listeria monocytogenes. Notably, Berberine hydrochloride improved pathogen resistance by reducing bacterial load in the intestine. Screening of classical innate immune pathways in Caenorhabditis elegans revealed that Berberine hydrochloride conferred protection against infections through the p38 MAPK pathway, specifically by activating p38/PMK-1 signaling in the intestine to bolster innate immunity. Furthermore, Berberine hydrochloride also stimulated innate immunity in mice via the p38 MAPK pathway and significantly reduced bacterial load in the lungs. These findings indicate that Berberine hydrochloride may have therapeutic potential for protecting host from infectious diseases.

Chlorogenic acid inhibits Pseudomonas toxin pyocyanin and activates mitochondrial UPR to protect host against pathogen infection

Mitochondria are required for protecting host against pathogenic bacteria by activating mitochondrial unfolded protein response (UPRmt). Chlorogenic acid (CGA), a phenolic acid compound of green coffee extracts and tea has been shown to exhibit activities such as antioxidant, antibacterial, hepatoprotective, cardioprotective, anti-inflammatory, neuroprotective, anti-obesity. However, whether CGA regulates innate immunity and the underlying molecular mechanisms remain unknown. In this study, we found that CGA increased resistance to Gram-negative pathogen Pseudomonas aeruginosa PA14 in dose dependent manner. Meanwhile, CGA enhanced innate immunity in Caenorhabditis elegans by reducing intestinal bacterial burden. CGA also inhibited the proliferation of pathogenic bacteria. Importantly, CGA inhibited the production of Pseudomonas toxin pyocyanin (PYO) to protect C. elegans from P. aeruginosa PA14 infection. Furthermore, CGA activated the UPRmt and expression of antibacterial peptide genes to promote innate immunity in C. elegans via transcription factor ATFS-1(activating transcription factor associated with stress-1). Unexpectedly, CGA enhanced innate immunity independently of other known innate immune pathways. Intriguingly, CGA also protected mice from P. aeruginosa PA14 infection and activated UPRmt. Our work revealed a conserved mechanism by which CGA promoted innate immunity and boosted its therapeutic application in the treatment of pathogen infection.

Antimicrobial peptide 2K4L inhibits the inflammatory response in macrophages and Caenorhabditis elegans and protects against LPS-induced septic shock in mice

2K4L is a rationally designed analog of the short α-helical peptide temporin-1CEc, a natural peptide isolated and purified from the skin secretions of the Chinese brown frog Rana chensinensis by substituting amino acid residues. 2K4L displayed improved and broad-spectrum antibacterial activity than temporin-1CEc in vitro. Here, the antibacterial and anti-inflammatory activities of 2K4L in macrophages, C. elegans and mice were investigated. The results demonstrated that 2K4L could enter THP-1 cells to kill a multidrug-resistant Acinetobacter baumannii strain (MRAB 0227) and a sensitive A. baumannii strain (AB 22933), as well as reduce proinflammatory responses induced by MRAB 0227 by inhibiting NF-κB signaling pathway. Similarly, 2K4L exhibited strong bactericidal activity against A. baumannii uptake into C. elegans, extending the lifespan and healthspan of the nematodes. Meanwhile, 2K4L alleviated the oxidative stress response by inhibiting the expression of core genes in the p38 MAPK/PMK-1 signaling pathway and downregulating the phosphorylation level of p38, thereby protecting the nematodes from damage by A. baumannii. Finally, in an LPS-induced septic model, 2K4L enhanced the survival of septic mice and decreased the production of proinflammatory cytokines by inhibiting the signaling protein expression of the MAPK and NF-κB signaling pathways and protecting LPS-induced septic mice from a lethal inflammatory response. In conclusion, 2K4L ameliorated LPS-induced inflammation both in vitro and in vivo.

Structural characterization and innate immunomodulatory effect of glucomannan from Bletilla striata

The crude polysaccharide of Bletilla striata in this study was extracted by water extraction and alcohol precipitation and further purified by gel column to yield the purified component Bletilla striata polysaccharide (BSP). Its structure and innate immune regulation activity were studied. BSP mainly comprises mannose and glucose, with a monosaccharide molar ratio of 2.9:1 and a weight-average molecular weight of 28,365 Da. It is a new low-molecular-weight water-soluble neutral glucomannan. BSP contains a → 6)-β-Manp-(1→, →4)-β-Glcp-(1→, →4)-β-Manp-(1 → and →3)-α-Manp-(1 → linear main chain, containing β-Glcp-(1 → and β-Manp-(1 → two branched chain fragments were connected to the Man residue at position 4. BSP can enhance the anti-infection ability of Caenorhabditis elegans against Pseudomonas aeruginosa, significantly improve the phagocytic ability of RAW264.7 macrophages, stimulate the secretion of NO and TNF-α, and have good innate immune regulation activity. These findings guide the use of Bletilla striata polysaccharides with immunomodulatory action.

Low-dose naltrexone extends healthspan and lifespan in C. elegans via SKN-1 activation

As the global aging population rises, finding effective interventions to improve aging health is crucial. Drug repurposing, utilizing existing drugs for new purposes, presents a promising strategy for rapid implementation. We explored naltrexone from the Library of Integrated Network-based Cellular Signatures (LINCS) based on several selection criteria. Low-dose naltrexone (LDN) has gained attention for treating various diseases, yet its impact on longevity remains underexplored. Our study on C. elegans demonstrated that a low dose, but not high dose, of naltrexone extended the healthspan and lifespan. This effect was mediated through SKN-1 (NRF2 in mammals) signaling, influencing innate immune gene expression and upregulating oxidative stress responses. With LDN's low side effects profile, our findings underscore its potential as a geroprotector, suggesting further exploration for promoting healthy aging in humans is warranted.

Caffeic acid activates mitochondrial UPR to resist pathogen infection in Caenorhabditis elegans via the transcription factor ATFS-1

Mitochondria play roles in the resistance of Caenorhabditis elegans against pathogenic bacteria by regulating mitochondrial unfolded protein response (UPRmt). Caffeic acid (CA) (3,4-dihydroxy cinnamic acid) is a major phenolic compound present in several plant species, which exhibits biological activities such as antioxidant, anti-fibrosis, anti-inflammatory, and anti-tumor properties. However, whether caffeic acid influences the innate immune response and the underlying molecular mechanisms remains unknown. In this study, we find that 20 µM caffeic acid enhances innate immunity to resist the Gram-negative pathogen Pseudomonas aeruginosa infection in C. elegans. Meanwhile, caffeic acid also inhibits the growth of pathogenic bacteria. Furthermore, caffeic acid promotes host immune response by reducing the bacterial burden in the intestine. Through genetic screening in C. elegans, we find that caffeic acid promotes innate immunity via the transcription factor ATFS-1. In addition, caffeic acid activates the UPRmt and immune response genes for innate immune response through ATFS-1. Our work suggests that caffeic acid has the potential to protect patients from pathogen infection.

Disrupting the SKN-1 homeostat: mechanistic insights and phenotypic outcomes

The mechanisms that govern maintenance of cellular homeostasis are crucial to the lifespan and healthspan of all living systems. As an organism ages, there is a gradual decline in cellular homeostasis that leads to senescence and death. As an organism lives into advanced age, the cells within will attempt to abate age-related decline by enhancing the activity of cellular stress pathways. The regulation of cellular stress responses by transcription factors SKN-1/Nrf2 is a well characterized pathway in which cellular stress, particularly xenobiotic stress, is abated by SKN-1/Nrf2-mediated transcriptional activation of the Phase II detoxification pathway. However, SKN-1/Nrf2 also regulates a multitude of other processes including development, pathogenic stress responses, proteostasis, and lipid metabolism. While this process is typically tightly regulated, constitutive activation of SKN-1/Nrf2 is detrimental to organismal health, this raises interesting questions surrounding the tradeoff between SKN-1/Nrf2 cryoprotection and cellular health and the ability of cells to deactivate stress response pathways post stress. Recent work has determined that transcriptional programs of SKN-1 can be redirected or suppressed to abate negative health outcomes of constitutive activation. Here we will detail the mechanisms by which SKN-1 is controlled, which are important for our understanding of SKN-1/Nrf2 cytoprotection across the lifespan.

Dioscin Activates Endoplasmic Reticulum Unfolded Protein Response for Defense Against Pathogenic Bacteria in Caenorhabditis elegans via IRE-1/XBP-1 Pathway

The unfolded protein response (UPR) is an evolutionarily conserved pathway that senses and responds to the accumulation of misfolded proteins in the endoplasmic reticulum (ER) lumen during bacterial infection. The IRE-1/XBP-1 pathway is a major branch of the UPRER that has been conserved from yeast to human. Dioscin, a steroidal saponin exhibits a broad spectrum of properties. However, whether dioscin influences the immune response and the underlying molecular mechanisms remain obscure. We find that dioscin increases resistance to Gram-negative pathogen Pseudomonas aeruginosa. Furthermore, dioscin also inhibits the growth of pathogenic bacteria. Meanwhile, dioscin enhances the resistance to pathogens by reducing bacterial burden in the intestine. Through genetic screening, we find that dioscin activates the UPRER to promote innate immunity via IRE-1/XBP-1 pathway. Intriguingly, dioscin requires the neural XBP-1 for immune response. Our findings suggest that dioscin may be a viable candidate for the treatment of infectious diseases.

The homeodomain transcription factor CEH-37 regulates PMK-1/p38 MAPK pathway to protect against intestinal infection via the phosphatase VHP-1

Increasing evidence indicate that the expression of defense genes at the right place and the right time are regulated by host-defense transcription factors. However, the precise mechanisms of this regulation are not well understood. Homeodomain transcription factors, encoded by homeobox genes, play crucial role for the development of multicellular eukaryotes. In this study, we demonstrated that homeodomain transcription factor CEH-37 (known as OTX2 in mammals) was a key transcription factor for host defense in Caenorhabditis elegans. Meanwhile, CEH-37 acted in the intestine to protect C. elegans against pathogen infection. We further showed that the homeodomain transcription factor CEH-37 positively regulated PMK-1/ p38 MAPK activity to promote the intestinal immunity via suppression phosphatase VHP-1. Furthermore, we demonstrated that this function was conserved, because the human homeodomain transcription factor OTX2 also exhibited protective function in lung epithelial cells during Pseudomonas aeruginosa infection. Thus, our work reveal that CEH-37/OTX2 is a evolutionarily conserved transcription factor for defense against pathogen infection. The finding provides a model in which CEH-37 decreases VHP-1 phosphatase activity, allowing increased stimulation of PMK-1/p38 MAPK phosphorylation cascade in the intestine for pathogen resistance.

6-Methoxydihydrosanguinarine exhibits cytotoxicity and sensitizes TRAIL-induced apoptosis of hepatocellular carcinoma cells through ROS-mediated upregulation of DR5

6-methoxydihydrosanguinarine (6-MS), a natural benzophenanthridine alkaloid extracted from Macleaya cordata (Willd.) R. Br, has shown to trigger apoptotic cell death in cancer cells. However, the exact mechanisms involved have not yet been clarified. The current study reveals the underlying mechanisms of 6-MS-induced cytotoxicity in hepatocellular carcinoma (HCC) cells and investigates whether 6-MS sensitizes TNF-related apoptosis inducing ligand (TRAIL)-induced apoptosis. 6-MS was shown to suppress cell proliferation and trigger cell cycle arrest, DNA damage, and apoptosis in HCC cells. Mechanisms analysis indicated that 6-MS promoted reactive oxygen species (ROS) generation, JNK activation, and inhibits EGFR/Akt signaling pathway. DNA damage and apoptosis induced by 6-MS were reversed following N-acetyl-l-cysteine (NAC) treatment. The enhancement of PARP cleavage caused by 6-MS was abrogated by pretreatment with JNK inhibitor SP600125. Furthermore, 6-MS enhanced TRAIL-mediated HCC cells apoptosis by upregulating the cell surface receptor DR5 expression. Pretreatment with NAC attenuated 6-MS-upregulated DR5 protein expression and alleviated cotreatment-induced viability reduction, cleavage of caspase-8, caspase-9, and PARP. Overall, our results suggest that 6-MS exerts cytotoxicity by modulating ROS generation, EGFR/Akt signaling, and JNK activation in HCC cells. 6-MS potentiates TRAIL-induced apoptosis through upregulation of DR5 via ROS generation. The combination of 6-MS with TRAIL may be a promising strategy and warrants further investigation.

Insights into the potential of Sanguinarine as a promising therapeutic option for breast cancer

Breast cancer (BC) is one of the leading causes of cancer-related deaths in women worldwide. The tumor microenvironment (TME) plays a crucial role in the progression and metastasis of BC. A significant proportion of BC is characterized by a hypoxic TME, which contributes to the development of drug resistance and cancer recurrence. Sanguinarine (SAN), an isoquinoline alkaloid found in Papaver plants, has shown promise as an anticancer agent. The present review focuses on exploring the molecular mechanisms of hypoxic TME in BC and the potential of SAN as a therapeutic option. The review presents the current understanding of the hypoxic TME, its signaling pathways, and its impact on the progression of BC. Additionally, the review elaborates on the mechanisms of action of SAN in BC, including its effects on vital cellular processes such as proliferation, migration, drug resistance, and tumor-induced immune suppression. The review highlights the importance of addressing hypoxic TME in treating BC and the potential of SAN as a promising therapeutic option.

Preclinical safety evaluation of Macleaya Cordata extract: A re-assessment of general toxicity and genotoxicity properties in rodents

Macleaya cordata extract (MCE) is widely used for its diverse pharmacological actions and beneficial effects on farm animals. Modern pharmacological studies have shown that it has anti-inflammatory, anti-cancer, and anti-bacterial activities, and is gradually becoming a long-term additive veterinary drug used to improve animal intestinal health and growth performance. Although some evidence points to the DNA mutagenic potential of sanguinarine (SAN), a major component of MCE, there is a lack of sufficient basic toxicological information on the oral route, posing a potential safety risk for human consumption of food of animal origin. In this study, we assessed the acute oral toxicity, repeated 90-day oral toxicity and 180-day chronic toxicity of MCE in rats and mice and re-evaluated the genotoxicity of MCE using a standard combined in vivo and ex vivo assay. In the oral acute toxicity test, the LD₅₀ for MCE in rats and mice was 1,564.55 mg/kg (95% confidence interval 1,386.97–1,764.95 mg/kg) and 1,024.33 mg/kg (95% confidence interval 964.27–1,087.30 mg/kg), respectively. The dose range tested had no significant effect on hematology, clinical chemistry, and histopathological findings in rodents in the long-term toxicity assessment. The results of the bacterial reverse mutation, sperm abnormality and micronucleus test showed negative results and lack of mutagenicity and teratogenicity; the results of the rat teratogenicity test showed no significant reproductive or embryotoxicity. The results indicate that MCE was safe in the dose range tested in this preclinical safety assessment. This study provides data to support the further development of maximum residue limits (MRLs) for MCE.