Arctigenin suppresses cell proliferation via autophagy inhibition in hepatocellular carcinoma cells

Quantitative Determination of the Cytotoxic Compounds in Different Organs of Arctium minus (Hill) Bernh. by LC-HRESIMS Using Respond Survey Methodology

Arctium minus (Hill) Bernh., commonly known as "Burdock", is a species within the Arctium genus of the Asteraceae family. Determining the optimum extraction conditions to obtain a concentrated extract with targeted active ingredients guides the most efficient use of natural products. Herein, ultrasound-assisted extraction (UAE) was optimized by using response surface methodology (RSM) to extract bioactive compounds from different organs of A. minus. Furthermore, phytochemical composition of extracts of the A. minus was investigated by using liquid chromatography-high resolution electrospray ionization mass spectrometry (LC-HRESIMS), antioxidant potential by using 2,2-diphenyl-1-picrylhydrazyl (DPPH), diazanium;3-ethyl-2-[(3-ethyl-6-sulfonato-1,3-benzothiazol-2-ylidene)hydrazinylidene]-1,3-benzothiazole-6-sulfonate (ABTS), CUPRAC, and metal chelation assays, and cytotoxic activities by using human breast cancer cell line (MDA-MB-231) and hepatocellular carcinoma cancer cell line (HepG2), and compared against conventional methods; Soxhlet and maceration. The RSM was employed to investigate the influence of ultrasound power, extraction time, and extraction temperature on the antioxidant potential assessed by the DPPH free radical scavenging assay. In UAE of A. minus leaves, flowers, and branches, the conditions resulting in the minimum IC50 values: 20 °C for 6 min at 50 W for leaves, 20 °C for 3 min at 100 W for flowers, and 20 °C for 3 min at 100 W for branches. Chlorogenic acid was identified as the major phenolic compound in the extracts obtained by UAE, with concentrations of 24,666.96 μg/g in leaves, 1054.92 μg/g in flowers, and 3,501.24 μg/g in branches. Flowers of A. minus had significantly higher levels of arctiin and arctigenin than those of leaves and branches. Extracts from leaves and flowers were more effective against MDA-MB-231 and HepG2 cancer cell lines than arctiin and arctigenin.

Chemoproteomics reveals arctigenin as a phagophore-closure blocker via targeting ESCRT-I subunit VPS28

Arctigenin is the active ingredient of the traditional medicines Arctium lappa and Fructus Arctii and has been extensively investigated for its diverse pharmacological functions, including its novel anti-austerity activity. Although several mechanisms have been proposed, the direct target of arctigenin to induce anti-austerity activity remains unclear. In this study, we designed and synthesized photo-crosslinkable arctigenin probes and utilized them in the chemoproteomic profiling of potential target proteins directly in living cells. Vacuolar protein sorting-associated protein 28 (VPS28), a key subunit of the ESCRT-I complex implicated in phagophore closure, was successfully identified. Unexpectedly, we found that arctigenin degraded VPS28 via the ubiquitin-proteasome pathway. We also demonstrated that arctigenin induces a prominent phagophore closure-blockade phenotype in PANC-1 cells. To the best of our knowledge, this is the first report of a small molecule acting as a phagophore-closure blocker and a VPS28 degrader. The arctigenin-modulating phagophore closure provides a new druggable target for cancers that rely heavily on autophagy activation and may also be used for other diseases associated with the ESCRT system.

The therapeutic potential of arctigenin against multiple human diseases: A mechanistic review

BACKGROUND

Arctigenin (ATG), a dibenzyl butyrolactone lignan compound, is one of the major bioactive components from the medicinal plant Arctium lappa. ATG possesses remarkable therapeutic potential against a wide range of human diseases, such as cancers, immune disorders and chronical diseases. The molecular mechanisms behind the biological effects of ATG have been intensively studied.

PURPOSE

This review aims to systematically summarize the updated knowledge of the proteins and signaling pathways behind the curative property of ATG, and further analyze the potential connections between them.

METHOD

SciFinder, Pubmed, Web of Science and Cochrane Library databases were queried for publications reporting the therapeutic properties of ATG. "Arctigenin", "disease", "cancer", "inflammation", "organ damage", "infection", "toxicity" and "pharmacokinetics" were used as the searching titles.

RESULT

625 publications were identified and 95 met the inclusion criteria and exclusion criteria. 42 studies described the molecular mechanisms implicated in ATG treatments. Several proteins including phosphodiesterase subtype 4D (PDE4D), estrogen receptor (ER) β, protein phosphatase 2A (PP2A), phosphoinositide 3-kinase (PI3K) and transmembrane protein 16A (TMEM16A) are targeted by ATG in different settings. The frequently described signaling pathways are TLR4/NF-κB, PI3K/AKT/mTOR, AMP-activated protein kinase (AMPK) and nuclear factor erythroid 2-related factor 2 (Nrf-2) signalings.

CONCLUSION

Inhibition of PI3K/AKT pathway and activation of AMPK signaling play the pivotal roles in the therapeutic effects of ATG. PI3K/AKT and AMPK signaling widely link to other signaling pathways, modulating various biological processes such as anti-inflammation, anti-oxidative stress, anti-fibrosis, anti-ER stress, anti-steatosis and pro-apoptosis, which constitute the curative mechanisms of ATG against multiple human diseases.

Serial five-membered lactone ring ions in the treatment of Alzheimer's diseases-comprehensive profiling of arctigenin metabolites and network analysis

Arctigenin is a phenylpropanoid dibenzylbutyro lactone lignan compound with multiple biological functions. Previous studies have shown that arctigenin have neuroprotective effects in Alzheimer's disease (AD) models both in vivo and in vitro; however, its metabolism in vivo has not been studied. Most traditional analytical methods only partially characterize drug metabolite prototypes, so there is an urgent need for a research strategy that can fully characterize drug metabolites. In the present study, ions fishing with a serial five-membered lactone ring as a fishhook strategy based on ultrahigh-performance liquid chromatography-Q-Exactive Orbitrap mass spectrometry (UHPLC-Q-Exactive Orbitrap MS) was utilised to characterise the metabolism of arctigenin, and the establishment of this strategy also solved the challenge of creating a comprehensive metabolic profile of neolignan. Based on the proposed strategy, a total of 105 metabolites were detected and characterised, 76 metabolites of which were found in rats and 49 metabolites in liver microsomes. These metabolites were postulated to be produced through oxidation, reduction, hydrolysis, and complex reactions. Subsequently, network pharmacology was utilized to elucidate the mechanism of arctigenin and its main metabolites against Alzheimer's disease, screening 381 potential targets and 20 major signaling pathways. The study on the comprehensive metabolism of arctigenin provides a holistic metabolic profile, which will help to better understand the mechanism of arctigenin in the treatment of Alzheimer's disease (AD) and also provide a basis for the safe administration of arctigenin.

The first high-quality chromosomal genome assembly of a medicinal and edible plant Arctium lappa

Arctium lappa has a long medicinal and edible history with great economic importance. Here, the first high-quality chromosome-level draft genome of A. lappa was presented by the Illumina and PacBio sequencing data. The assembled genome was approximately 1.79 Gb with a N50 contig size of 6.88 Mb. Approximately 1.70 Gb (95.4%) of the contig sequences were anchored onto 18 chromosomes using Hi-C data; the scaffold N50 was improved to be 91.64 Mb. Furthermore, we obtained 1.12 Gb (68.46%) of repetitive sequences and 32,771 protein-coding genes; 616 positively selected candidate genes were identified. Among candidate genes related to lignan biosynthesis, the following were found to be highly correlated with the accumulation of arctiin: 4-coumarate-CoA ligase (4CL), dirigent protein (DIR), and hydroxycinnamoyl transferase (HCT). Additionally, we compared the transcriptomes of A. lappa roots at three different developmental stages and identified 8,943 differentially expressed genes (DEGs) in these tissues. These data can be utilized to identify genes related to A. lappa quality or provide a basis for molecular identification and comparative genomics among related species.

The Potential Application of Chinese Medicine in Liver Diseases: A New Opportunity

Liver diseases have been a common challenge for people all over the world, which threatens the quality of life and safety of hundreds of millions of patients. China is a major country with liver diseases. Metabolic associated fatty liver disease, hepatitis B virus and alcoholic liver disease are the three most common liver diseases in our country, and the number of patients with liver cancer is increasing. Therefore, finding effective drugs to treat liver disease has become an urgent task. Chinese medicine (CM) has the advantages of low cost, high safety, and various biological activities, which is an important factor for the prevention and treatment of liver diseases. This review systematically summarizes the potential of CM in the treatment of liver diseases, showing that CM can alleviate liver diseases by regulating lipid metabolism, bile acid metabolism, immune function, and gut microbiota, as well as exerting anti-liver injury, anti-oxidation, and anti-hepatitis virus effects. Among them, Keap1/Nrf2, TGF-β/SMADS, p38 MAPK, NF-κB/IκBα, NF-κB-NLRP3, PI3K/Akt, TLR4-MyD88-NF-κB and IL-6/STAT3 signaling pathways are mainly involved. In conclusion, CM is very likely to be a potential candidate for liver disease treatment based on modern phytochemistry, pharmacology, and genomeproteomics, which needs more clinical trials to further clarify its importance in the treatment of liver diseases.

Arctigenin, an anti-tumor agent; a cutting-edge topic and up-to-the-minute approach in cancer treatment

Today, herbal-derived compounds are being increasingly studied in cancer treatment. Over the past decade, Arctigenin has been introduced as a bioactive dibenzylbutyrolactone lignan which is found in Chinese herbal medicines. In addition to anti-microbial, anti-inflammatory, immune-modulatory functions, Arctigenin has attracted growing attention due to its anti-tumor capabilities. It has been shown that Arctigenin can induce apoptosis and necrosis and abolish drug resistance in tumor cells by inducing apoptotic signaling pathways, caspases, cell cycle arrest, and the modulating proteasome. Moreover, Arctigenin mediates other anti-tumor functions through several mechanisms. It has been demonstrated that Arctigenin can act as an anti-inflammatory compound to inhibit inflammation in the tumor microenvironment. It also downregulates factors involved in tumor metastasis and angiogenesis, such as matrix metalloproteinases, N-cadherin, TGF-β, and VEGF. Additionally, Arctigenin, through modulation of MAPK signaling pathways and stress-related proteins, is able to abolish tumor cell growth in nutrient-deprived conditions. Due to the limited solubility of Arctigenin in water, it is suggested that modification of this compound through amino acid esterification can improve its pharmacogenetic properties. Collectively, it is hoped that using Arctigenin or its derivates might introduce new chemotherapeutic approaches in future treatment.

Steroidal Saponins Isolated from the Rhizome of Dioscorea tokoro Inhibit Cell Growth and Autophagy in Hepatocellular Carcinoma Cells

Our preliminary screening identified an extract from the rhizome of Dioscorea tokoro, which strongly suppressed the proliferation of HepG2 hepatocellular carcinoma cells and inhibited autophagy. This study aimed to isolate active compounds from the rhizome of D. tokoro that exert antiproliferative effects and inhibit autophagy. The bioassay-guided fractionation of the active fraction led to the isolation of two spirostan-type steroidal saponins, dioscin (1) and yamogenin 3-O-α-l-rhamnopyranosyl (1→4)-O-α-l-rhamnopyranosyl(1→2)-β-d-glucopyranoside (2), and the frostane-type steroidal saponin protodioscin (3) from the n-BuOH fraction. Furthermore, acid hydrolysis of 1 and 2 produced the aglycones diosgenin (4) and yamogenin (5), respectively. Compounds 1-5 suppressed proliferation of HepG2 cells. The analysis of structure-activity relationships indicated that the 25(R)-conformation, structures with a sugar moiety, and the spirostan-type aglycone moiety contributed to antiproliferative activity. Analysis of autophagy-related proteins demonstrated that 1-3 clearly increased the levels of both LC3-II and p62, implying that 1-3 deregulate the autophagic pathway by blocking autophagic flux, which results in p62 and LC3-II accumulation. In contrast, 1-3 did not significantly affect caspase-3 activation and PARP cleavage, suggesting that the antiproliferative activity of 1-3 occurred independently of caspase-3-mediated apoptosis. In summary, our study showed that 1-3, active compounds in the rhizome of D. tokoro, suppressed cell proliferation and autophagy, and might be potential agents for autophagy research and cancer chemoprevention.

Costunolide and dehydrocostuslactone from Saussurea lappa root inhibit autophagy in hepatocellular carcinoma cells

Autophagy is a catabolic process for degradation of intracellular components and plays an important role in the development and growth of cancer. Our preliminary screening confirmed that an extract from the root of Saussurea lappa remarkably suppressed the proliferation of HepG2 hepatocellular carcinoma cells and inhibited autophagy. In this study, we explored the effects of costunolide (CL) and dehydrocostuslactone (DCL), which are bioactive sesquiterpene lactones in this extract, on autophagy modulation in HepG2 cells. An analysis of autophagy-related proteins demonstrated that CL and DCL blocks the autophagy process that leads to the accumulation of microtubule-associated protein 1 light chain 3 (LC3) and SQSTM1/p62 (p62). LC3 turnover assays indicated that CL and DCL trigger autophagy inhibition by blocking the autophagic flux, thereby resulting in the accumulation of LC3-II and p62. These results are encouraging and warrant further study of CL and DCL for potential use as autophagy inhibiting agents for liver cancer therapy.

Arctigenin Inhibits Glioblastoma Proliferation through the AKT/mTOR Pathway and Induces Autophagy

Purpose

Arctigenin (ARG) is a natural lignan compound extracted from Arctium lappa and has displayed anticancer function and therapeutic effect in a variety of cancers. Arctigenin is mainly from Arctium lappa extract. It has been shown to induce autophagy in various cancers. However, as for whether arctigenin induces autophagy in gliomas or not, the specific mechanism is still worth exploring.

Methods

Using CCK8, the monoclonal experiment was made to detect the proliferation ability. The scratch experiment and the transwell experiment were applied to the migration and invasion ability. PI/RNase and FITC-conjugated anti-annexin V were used to detect the cell cycle and apoptosis. Western blotting was used to determine the specified protein level, and constructed LC3B-GFP plasmid was used for analysis of autophagy.

Results

Our research showed that ARG inhibited the growth and proliferation and invasion and migration of glioma cells in a dose-dependent manner (U87MG and T98G) and arrested the cell cycle and induced apoptosis. Interestingly, ARG induced autophagy in a dose-dependent manner. We applied Western blotting to measure the increase in the key autophagy protein LC3B, as well as some other autophagy-related proteins (increase in Beclin-1 and decrease in P62). In order to further explore the mechanism that ARG passed initiating autophagy to inhibit cell growth, we further found by Western blotting that AKT and mTOR phosphorylation proteins (P-AKT, P-mTOR) were reduced after ARG treatment, and we used AKT agonists to rescue, and the phosphorylated proteins of AKT and mTOR increased, and we found that the autophagy-related proteins were also reversed. And interestingly, the protein of apoptosis was also reversed along with autophagy.

Conclusions

We thought ARG inhibited the proliferation of glioma cells by inducing autophagy and apoptosis through the AKT/mTOR pathway.

Polyphenol-Mediated Autophagy in Cancer: Evidence of In Vitro and In Vivo Studies

One of the hallmarks of cellular transformation is the altered mechanism of cell death. There are three main types of cell death, characterized by different morphological and biochemical features, namely apoptosis (type I), autophagic cell death (type II) and necrosis (type III). Autophagy, or self-eating, is a tightly regulated process involved in stress responses, and it is a lysosomal degradation process. The role of autophagy in cancer is controversial and has been associated with both the induction and the inhibition of tumor growth. Autophagy can exert tumor suppression through the degradation of oncogenic proteins, suppression of inflammation, chronic tissue damage and ultimately by preventing mutations and genetic instability. On the other hand, tumor cells activate autophagy for survival in cellular stress conditions. Thus, autophagy modulation could represent a promising therapeutic strategy for cancer. Several studies have shown that polyphenols, natural compounds found in foods and beverages of plant origin, can efficiently modulate autophagy in several types of cancer. In this review, we summarize the current knowledge on the effects of polyphenols on autophagy, highlighting the conceptual benefits or drawbacks and subtle cell-specific effects of polyphenols for envisioning future therapies employing polyphenols as chemoadjuvants.