Amentoflavone Inhibits Hepatocellular Carcinoma Progression Through Blockage of ERK/NF-ĸB Activation

Total biflavonoids extraction from Selaginella chaetoloma utilizing ultrasound-assisted deep eutectic solvent: Optimization of conditions, extraction mechanism, and biological activity in vitro

In this study, the deep eutectic solvent based ultrasound-assisted extraction (DES-UAE) was investigated for the efficient and environmentally friendly extraction of Selaginella chaetoloma total biflavonoids (SCTB). As an extractant for optimization, tetrapropylaminium bromide-1,4-butanediol (Tpr-But) was employed for the first time. 36 DESs were created, with Tpr-But producing the most effective results. Based on response surface methodology (RSM), the greatest extraction rate of SCTB was determined to be 21.68 ± 0.78 mg/g, the molar ratio of HBD to HBA was 3.70:1, the extraction temperature was 57 °C, and the water content of DES was 22 %. In accordance with Fick's second rule, a kinetic model for the extraction of SCTB by DES-UAE has been derived. With correlation coefficients 0.91, the kinetic model of the extraction process was significantly correlated with the general and exponential equations of kinetics, and some important kinetic parameters such as rate constants, energy of activation and raffinate rate were determined. In addition, molecular dynamics simulations were used to study the extraction mechanisms generated by different solvents. Comparing the effect of several extraction methods on S.chaetoloma using ultrasound-assisted extraction and conventional methods, together with SEM examination, revealed that DES-UAE not only saved time but also enhanced SCTB extraction rate by 1.5-3 folds. SCTB demonstrated superior antioxidant activity in three studies in vitro. Furthermore, the extract could suppress the growth of A549, HCT-116, HepG2, and HT-29 cancer cells. Alpha-Glucosidase (AG) inhibition experiment and molecular docking studies suggested that SCTB exhibited strong inhibitory activity against AG and potential hypoglycemic effects. The results of this study indicated that a Tpr-But-based UAE method was suitable for the efficient and environmentally friendly extraction of SCTB, and also shed light on the mechanisms responsible for the increased extraction efficiency, which could aid in the application of S.chaetoloma and provide insight into the extraction mechanism of DES.

Inactivation of EGFR/ERK/NF-κB signalling associates with radiosensitizing effect of 18β-glycyrrhetinic acid on progression of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is recognized as the fifth most common cancer and the third most common cause of death in Asian population. Studies reported that HCC is relatively insensitive to radiotherapy (RT); thus, considering how to sensitize HCC to RT is worth to be elucidated. Epidermal growth factor receptor (EGFR)-mediated signalling transduction plays the important role in regulating treatment efficacy of HCC. An active compound, 18beta-glycyrrhetinic acid (18β-GA), has been reported to own anti-tumour effect. However, whether 18β-GA possess RT sensitization ability in HCC remains unclear. Here, we used RNA data from TCGA-LIHC (Liver hepatocellular carcinoma) to identify the role between EGFR/ERK/nuclear factor kappa B (NF-κB) signalling and RT by radiosensitivity index (RSI) analysis. We suggested that patients with activated NF-κB signalling may show resistance to RT treatment, whereas combining 18β-GA may reinforce RT efficacy in a Hep3B-bearing animal model. 18β-GA combined with RT showed superior tumour inhibition capacity as compared to monotherapy and even reached similar efficacy as erlotinib combined with RT. Treatment promotion of RT by 18β-GA in HCC is not only through diminishing RT-induced EGFR/ERK/NF-κB signalling but also promoting RT-induced apoptosis pathways. 18β-GA may act as radiosensitizer through inactivating EGFR-mediated HCC progression and inducing caspase-dependent apoptosis signalling.

Amentoflavone induces caspase-dependent/-independent apoptosis and dysregulates cyclin-dependent kinase-mediated cell cycle in colorectal cancer in vitro and in vivo

Colorectal cancer (CRC) is recognized as the third most common malignancy and the second most deadly in highly developed countries. Although the treatment of CRC has improved in the past decade, the mortality rate of CRC is still increasing. Amentoflavone, one of the flavonoids detected in medical plants, is reported to possess potential anticancer properties in various cancers. However, its role in CRC has not been studied. This study aimed to investigate the role and underlying mechanism of amentoflavone on CRC in vitro and in vivo. We identified the cytotoxicity, apoptosis effect, cell cycle alteration, DNA damage induction and tumor progression inhibition of amentoflavone in HT-29 model by using MTT assay, flow cytometry, immunofluorescence (IF) staining, Western blotting and animal experiments. Amentoflavone induced cytotoxicity is caused by triggering G1 arrest, DNA damage and apoptosis in HT-29 cells. The expression of cyclin D1, CDK4 and CDK6 was decreased by amentoflavone; in contrast, the phosphorylation of ATM and CHK2 and the expression of p21 and p27 were increased. The apoptosis induction of amentoflavone in CRC is not only caspase-dependent but also increases EndoG and AIF nuclear translocation in a caspase-independent manner. Importantly, the apoptosis induction of amentoflavone is not affected by the activity of p53 in CRC. Amentoflavone suppressed the progression of CRC by initiating G1 arrest and ATM/CHK2-mediated DNA damage-responsive, caspase-dependent/independent apoptotic effects. We uncovered a novel tumor-inhibitory role of amentoflavone in CRC that is not associated with p53 activity, which may serve as a potential treatment for CRC.

Advances in the Anti-Tumor Activity of Biflavonoids in Selaginella

Despite the many strategies employed to slow the spread of cancer, the development of new anti-tumor drugs and the minimization of side effects have been major research hotspots in the anti-tumor field. Natural drugs are a huge treasure trove of drug development, and they have been widely used in the clinic as anti-tumor drugs. Selaginella species in the family Selaginellaceae are widely distributed worldwide, and they have been well-documented in clinical practice for the prevention and treatment of cancer. Biflavonoids are the main active ingredients in Selaginella, and they have good biological and anti-tumor activities, which warrant extensive research. The promise of biflavonoids from Selaginella (SFB) in the field of cancer therapy is being realized thanks to new research that offers insights into the multi-targeting therapeutic mechanisms and key signaling pathways. The pharmacological effects of SFB against various cancers in vitro and in vivo are reviewed in this review. In addition, the types and characteristics of biflavonoid structures are described in detail; we also provide a brief summary of the efforts to develop drug delivery systems or combinations to enhance the bioavailability of SFB monomers. In conclusion, SFB species have great potential to be developed as adjuvant or even primary therapeutic agents for cancer, with promising applications.

Phenolic Acid Profiling of Lactarius hatsudake Extracts, Anti-Cancer Function and Its Molecular Mechanisms

Cancer is still the leading cause of death across the world, and there is a lack of efficient therapies. Lactarius hatsudake is a mushroom with a food and medicine homology that contains numerous biologically active substances. This study aimed to investigate the composition of extracts from Lactarius hatsudake (L. hatsudake) and their anti-cancer function and molecular mechanisms. Our results showed that the total phenolic content of L. hatsudake extracts was 139.46 ± 5.42 mg/g. The following six phenolic compounds were identified from L. hatsudake extracts by HPLC and UPLC-QTOF/MS: gallic acid, pyrogallol, chlorogenic acid, ferulic acid, myricetin, and cinnamic acid. Colorectal cancer cell HCT116 and hepatic cancer cell HepG2 were used to evaluate the anti-cancer function of the L. hatsudake extracts. Compared with HepG2 cells, the L. hatsudake extracts showed stronger anti-cancer activity against HCT116 cells and these were used to study molecular mechanisms. The results indicated that the L. hatsudake extracts could arrest the cancer cell cycle and inhibit cancer cell proliferation, which may be mediated by the MAPK/NFκB/AP-1 signalling pathway; the L. hatsudake extracts also promoted cancer cell apoptosis through a mitochondrial-dependent pathway. Taken together, these findings demonstrate that L. hatsudake ethanol extracts contain six main phenolics and illustrate the remarkable potentiality of L. hatsudake as a source of natural phenolics for cancer prevention and as an adjuvant in the treatment of functional foods.

Insights Into Amentoflavone: A Natural Multifunctional Biflavonoid

Amentoflavone is an active phenolic compound isolated from Selaginella tamariscina over 40 years. Amentoflavone has been extensively recorded as a molecule which displays multifunctional biological activities. Especially, amentoflavone involves in anti-cancer activity by mediating various signaling pathways such as extracellular signal-regulated kinase (ERK), nuclear factor kappa-B (NF-κB) and phosphoinositide 3-kinase/protein kinase B (PI3K/Akt), and emerges anti-SARS-CoV-2 effect via binding towards the main protease (Mpro/3CLpro), spike protein receptor binding domain (RBD) and RNA-dependent RNA polymerase (RdRp) of SARS-CoV-2. Therefore, amentoflavone is considered to be a promising therapeutic agent for clinical research. Considering the multifunction of amentoflavone, the current review comprehensively discuss the chemistry, the progress in its diverse biological activities, including anti-inflammatory, anti-oxidation, anti-microorganism, metabolism regulation, neuroprotection, radioprotection, musculoskeletal protection and antidepressant, specially the fascinating role against various types of cancers. In addition, the bioavailability and drug delivery of amentoflavone, the molecular mechanisms underlying the activities of amentoflavone, the molecular docking simulation of amentoflavone through in silico approach and anti-SARS-CoV-2 effect of amentoflavone are discussed.

The inhibitory effect and mechanism of quetiapine on tumor progression in hepatocellular carcinoma in vivo

Hepatocellular carcinoma (HCC) is the primary tumor of the liver and the fourth leading cause of cancer-related death. Recently, several studies indicated the anti-tumor potential of antipsychotic medicine. Quetiapine, an atypical antipsychotic, is used to treat schizophrenia, bipolar disorder, and major depressive disorder since 1997. However, whether quetiapine may show potential to suppress HCC progression and its underlying mechanism is persisting unclear. Quetiapine has been shown to induce apoptosis and inhibit invasion ability in HCC in vitro. Here, we established two different HCC (Hep3B, SK-Hep1) bearing animals to identify the treatment efficacy of quetiapine. Tumor growth, signaling transduction, and normal tissue pathology after quetiapine treatment were validated by caliper, bioluminescence image, immunohistochemistry (IHC), and hematoxylin and eosin staining, respectively. Quetiapine suppressed HCC progression in a dose-dependent manner. Extracellular signal-regulated kinases (ERKs) and Nuclear factor-κB (NF-κB) mediated downstream proteins, such as myeloid leukemia cell differentiation protein (MCL-1), cellular FLICE-inhibitory protein (C-FLIP), X-linked inhibitor of apoptosis protein (XIAP), Cyclin-D1, matrix metallopeptidase 9 (MMP-9), vascular endothelial growth factor-A (VEGF-A) and indoleamine 2,3-dioxygenase (IDO) which involved in proliferation, survival, angiogenesis, invasion and anti-tumor immunity were all decreased by quetiapine. In addition, extrinsic/intrinsic caspase-dependent and caspase-independent pathways, including cleaved caspase-3, -8, and - 9 were increased by quetiapine. In sum, the tumor inhibition that results from quetiapine may associate with ERK and NF-κB inactivation.

Mechanism of HSP90 Inhibitor in the Treatment of DSS-induced Colitis in Mice by Inhibiting MAPK Pathway and Synergistic Effect of Compound Sophorae Decoction

BACKGROUND

The mechanism of Heat Shock Protein 90 (HSP90) in Ulcerative Colitis (UC) has been studied, and mitogenic-activated protein kinases (MAPK) also contribute to the pathogenesis of UC. However, the effect of the HSP90/MAPK pathway in UC is still unclear. Therefore, the mainstay of this research is to explore the mechanism of action of this pathway in UC. Compound sophorae decoction (CSD), as a Chinese herbal decoction, can synergistically affect the above process.

OBJECTIVE

This study aimed to uncover the synergistic effects of HSP90 inhibitors regulating the MAPK pathway for treating DSS-induced colitis in mice and the synergistic effects of CSD.

METHODS

This experiment used oral administration of standard diets containing 3% dextran sodium sulfate (DSS) to establish an experimental colitis model in mice. The model was treated with HSP90 inhibitor, CSD, or dexamethasone. Mouse feces, mobility, body weight, colon length, and colon histopathology scores were recorded daily to assess the degree of colitis inflammation. Expression levels of HSP90 and MAPK pathway-related genes and proteins were evaluated by Western blot and qPCR. The evaluation of intestinal mucosal permeability was measured by enzyme-linked immunosorbent assay (ELISA), which could detect the protein level of D-Amino Acid Oxidase (DAO) and D-lactic acid (D-LA). The same went for downstream molecules AFT-2, p53, and apoptosis-related proteins BAX, BCL-2, Caspase3, and survivin in the MAPK pathway. Immunohistochemical measured p-38, p-JNK, and p-ERK expressions. JAM-A and claudin-1 connexin were tested by immunofluorescence staining. The TUNEL method was for measuring the apoptosis rate of colonic epithelial cells. CBA kit determined the level of inflammatory factors of colons.

RESULTS

HSP90 inhibitor can improve the degree of pathological damage in the colon of mice treated with DSS, increase the mice's weight and the length of the colon, and significantly reduce the disease activity index (DAI) score. Intraperitoneal injection of HSP90 inhibitor can reduce the expression of MAPK pathway markers P38, JNK, ERK, and their phosphorylation and decrease the content of AFT-2 and p53, which is downstream of the MAPK pathway. In addition, treatment of the HSP90 inhibitor up-regulated the expression of anti-apoptotic proteins BCL-2 and survivin, as well as down-regulated apoptotic protein caspase3, BAX in the colon of mice with colitis. Lower levels of inflammatory factors such as IL-6, MCP-1, IFN-γ, TNF, IL-12p70, and increased IL-10 were observed after HSP90 inhibitor therapy. Furthermore, the combination treatment of CSD can enhance the effect of the single HSP90 inhibitor treatment and play a synergistic effect.

CONCLUSION

These data suggest that an HSP90 inhibitor is available to treat UC by inhibiting the MAPK signaling pathway. This axis can restore the intestinal mucosa barrier's function by reducing intestinal mucosa's permeability and inhibiting apoptosis of intestinal epithelial cells. The specific mechanism is that HSP90 inhibitor can reduce the pathological damage and inflammation levels of colitis mice, and reduce the apoptosis rate of colonic epithelial cells and the mucosal permeability, thereby restoring the mucosal barrier function. During this process, CSD works synergistically to improve the therapeutic effect of the HSP90 inhibitor.

The traditional and modern uses of Selaginella tamariscina (P.Beauv.) Spring, in medicine and cosmetic: Applications and bioactive ingredients

ETHNOPHARMACOLOGICAL RELEVANCE

Extracts of the plant Selaginella tamariscina (P.Beauv.) Spring (spike moss) are used for a long time in Asia, for the treatment of multiple diseases and conditions. Aqueous and alcoholic leave extracts are used by local communities. In China, the plant (Juan bai) is listed on the Pharmacopoeia. In South Korea, the use of this plant (Kwon Baek) is mentioned in the book Dongui-Bogam (Heo Jun 1613), at the origin of the Hyungsang medicine. S. tamariscina is traditionally used in Vietnam (mong lung rong), Thailand (dok hin), Philippines (pakong-tulog) and other Asian countries.

AIM OF THE STUDY

To provide an analysis of the multiple traditional and current uses of S. tamariscina extracts (STE) in the field of medicine and cosmetic. The review is also intended at identifying the main natural products at the origin of the many pharmacological properties reported with these extracts (anti-inflammatory, antioxidant, antidiabetic, antibacterial, antiallergic, anticancer effects).

METHODS

Extensive database retrieval, such as SciFinder and PubMed, was performed by using keywords like " Selaginella tamariscina", "spike moss", "Selaginellaceae ". Relevant textbooks, patents, reviews, and digital documents were consulted to collate all available scientific literature and to provide a complete science-based survey of the topic.

RESULTS

Different solvents and methods are used to prepare STE. The process can largely modify the natural product content and properties of the extracts. STE display a range of pharmacological effects, useful to treat metabolic disorders, several inflammatory diseases and various cancers. A specific carbonized extract (S. tamariscina carbonisatus) has shown hemostatic effects, whereas standard STE can promote blood circulation. Many patented STE-containing cosmetic preparations are reviewed here. Several biflavonoids (chiefly amentoflavone) and phenolic compounds (selaginellin derivatives) are primarily responsible for the observed pharmacological properties. Potent inhibitors of protein tyrosine phosphatase 1 B (PTP1B), phosphodiesterase-4 (PDE4), and repressor of pro-inflammatory cytokines expression have been identified from STE.

CONCLUSION

The traditional use of STE supports the research performed with this plant. There are robust experimental data, based on in vitro and in vivo models, documenting the use of STE to treat type 2 diabetes, several inflammatory diseases, and some cancers (in combination with standard chemotherapy). Selaginella tamariscina (P.Beauv.) is a prime reservoir for amentoflavone, and many other bioactive natural products. The interest of the plant in medicine and cosmetic is amply justified.

Hinokiflavone and Related C-O-C-Type Biflavonoids as Anti-cancer Compounds: Properties and Mechanism of Action

Biflavonoids are divided in two classes: C-C type compounds represented by the dimeric compound amentoflavone and C-O-C-type compounds typified by hinokiflavone (HNK) with an ether linkage between the two connected apigenin units. This later sub-group of bisflavonyl ethers includes HNK, ochnaflavone, delicaflavone and a few other dimeric compounds, found in a variety of plants, notably Selaginella species. A comprehensive review of the anticancer properties and mechanism of action of HNK is provided, to highlight the anti-proliferative and anti-metastatic activities of HNK and derivatives, and HNK-containing plant extracts. The anticancer effects rely on the capacity of HNK to interfere with the ERK1-2/p38/NFκB signaling pathway and the regulation of the expression of the matrix metalloproteinases MMP-2 and MMP-9 (with a potential direct binding to MMP-9). In addition, HNK was found to function as a potent modulator of pre-mRNA splicing, inhibiting the SUMO-specific protease SENP1. As such, HNK represents a rare SENP1 inhibitor of natural origin and a scaffold to design synthetic compounds. Oral formulations of HNK have been elaborated to enhance its solubility, to facilitate the compound delivery and to enhance its anticancer efficacy. The review shed light on the anticancer potential of C-O-C-type biflavonoids and specifically on the pharmacological profile of HNK. This compound deserves further attention as a regulator of pre-mRNA splicing, useful to treat cancers (in particular hepatocellular carcinoma) and other human pathologies.

Amentoflavone as an Ally in the Treatment of Cutaneous Leishmaniasis: Analysis of Its Antioxidant/Prooxidant Mechanisms

Treatment of leishmaniasis is a challenging subject. Although available, chemotherapy is limited, presenting toxicity and adverse effects. New drugs with antileishmanial activity are being investigated, such as antiparasitic compounds derived from plants. In this work, we investigated the antileishmanial activity of the biflavonoid amentoflavone on the protozoan Leishmania amazonensis. Although the antileishmanial activity of amentoflavone has already been reported in vitro, the mechanisms involved in the parasite death, as well as its action in vivo, remain unknown. Amentoflavone demonstrated activity on intracellular amastigotes in macrophages obtained from BALB/c mice (IC₅₀ 2.3 ± 0.93 μM). No cytotoxicity was observed and the selectivity index was estimated as greater than 10. Using BALB/c mice infected with L. amazonensis we verified the effect of an intralesional treatment with amentoflavone (0.05 mg/kg/dose, in a total of 5 doses every 4 days). Parasite quantification demonstrated that amentoflavone reduced the parasite load in treated footpads (46.3% reduction by limiting dilution assay and 56.5% reduction by Real Time Polymerase Chain Reaction). Amentoflavone decreased the nitric oxide production in peritoneal macrophages obtained from treated animals. The treatment also increased the expression of ferritin and decreased iNOS expression at the site of infection. Furthemore, it increased the production of ROS in peritoneal macrophages infected in vitro. The increase of ROS in vitro, associated with the reduction of NO and iNOS expression in vivo, points to the antioxidant/prooxidant potential of amentoflavone, which may play an important role in the balance between inflammatory and anti-inflammatory patterns at the infection site. Taken together these results suggest that amentoflavone has the potential to be used in the treatment of cutaneous leishmaniasis, working as an ally in the control and development of the lesion.

Natural Products as Inducers of Non-Canonical Cell Death: A Weapon against Cancer

Simple Summary

Anticancer therapeutic approaches based solely on apoptosis induction are often unsuccessful due to the activation of resistance mechanisms. The identification and characterization of compounds capable of triggering non-apoptotic, also called non-canonical cell death pathways, could represent an important strategy that may integrate or offer alternative approaches to the current anticancer therapies. In this review, we critically discuss the promotion of ferroptosis, necroptosis, and pyroptosis by natural compounds as a new anticancer strategy.

Abstract

Apoptosis has been considered the main mechanism induced by cancer chemotherapeutic drugs for a long time. This paradigm is currently evolving and changing, as increasing evidence pointed out that antitumor agents could trigger various non-canonical or non-apoptotic cell death types. A considerable number of antitumor drugs derive from natural sources, both in their naturally occurring form or as synthetic derivatives. Therefore, it is not surprising that several natural compounds have been explored for their ability to induce non-canonical cell death. The aim of this review is to highlight the potential antitumor effects of natural products as ferroptosis, necroptosis, or pyroptosis inducers. Natural products have proven to be promising non-canonical cell death inducers, capable of overcoming cancer cells resistance to apoptosis. However, as discussed in this review, they often lack a full characterization of their antitumor activity together with an in-depth investigation of their toxicological profile.

Combination of canstatin and arsenic trioxide suppresses the development of hepatocellular carcinoma

Complication of arsenic trioxide (ATO) and other drugs in cancer treatment has attracted much focus, but is limitedly investigated in hepatocellular carcinoma (HCC). This study aimed to explore the role of ATO combined with canstatin in HCC. HepG2 cells were treated with different concentrations of ATO with or without canstatin, CCK-8, flow cytometry, Transwell assays were conducted to determine cell proliferation, apoptosis, adhesion, migration, and invasion abilities. Besides, the protein expression or mRNA level of caspase-3, PCNA, and MMP-2 was measured using western blotting or qRT-PCR. BALB/c-nu/nu mice were used to establish nude mouse transplantation tumor model, and received ATO or canstatin treatment for 3 weeks. The results showed that ATO inhibited cell proliferation, adhesion, migration and invasion, and promoted cell apoptosis with a concentration-dependent way. Canstatin had a significantly inhibitory effect on cell proliferation, but had limited effects on the other cellular behaviors. Besides, combination with ATO and canstatin strengthened the effects of ATO alone on cell proliferation inhibition and cell apoptosis promotion. Moreover, both of ATO and canstatin increased the protein expression of caspase-3, while decreased PCNA and MMP-2, which was further strengthened upon their combination. Furthermore, both of ATO and canstatin inhibited tumor growth in vivo, which was also strengthened upon their combination. Collectively, we found that combined canstatin and ATO significantly inhibited cell proliferation, migration and adhesion abilities, and promoted cell apoptosis, and inhibited tumor growth, thus suppressed the progression of HCC.

Glycyrrhizic Acid Modulates Apoptosis through Extrinsic/Intrinsic Pathways and Inhibits Protein Kinase B- and Extracellular Signal-Regulated Kinase-Mediated Metastatic Potential in Hepatocellular Carcinoma In Vitro and In Vivo

A previous study presented that glycyrrhizic acid as the hepatoprotective agent inhibits total parenteral nutrition-associated acute liver injury in rats. However, the anticancer effect and mechanism of glycyrrhizic acid in human hepatocellular carcinoma (HCC) is ambiguous. The purpose of the present study was to investigate the effect of glycyrrhizic acid on apoptosis dysregulation and metastatic potential in HCC in vitro and in vivo. Both SK-Hep1 and Hep3B cells were treated with different concentrations of glycyrrhizic acid for 24 or 48h. SK-Hep1/luc2 tumor-bearing mice were treated with vehicle or glycyrrhizic acid (50mg/kg/day by intraperitoneal injection) for 7 days. Tumor cells growth, apoptotic, and metastatic signaling transduction were evaluated by using MTT assay, digital caliper, bioluminescence imaging (BLI), flow cytometry, western blotting assay, and immunohistochemistry (IHC) staining. The results demonstrated glycyrrhizic acid significantly inhibits tumor cell growth, cell invasion, and expression of AKT (Ser473), extracellular-signal-regulated kinase (ERK), epidermal growth factor receptor (EGFR) phosphorylation, anti-apoptotic and metastatic proteins in HCC in vitro and in vivo. Glycyrrhizic acid also significantly triggered apoptosis and extrinsic/intrinsic apoptotic signaling transduction. In addition, PD98059 (ERK inhibitor) and LY294002 (AKT inhibitor) obviously reduced cell invasion and expression of metastasis-associated proteins. Taken together, these results indicated that glycyrrhizic acid induces apoptosis through extrinsic/intrinsic apoptotic signaling pathways and diminishes EGFR/AKT/ERK-modulated metastatic potential in HCC in vitro and in vivo.

Amentoflavone Attenuates Clostridium perfringens Gas Gangrene by Targeting Alpha-Toxin and Perfringolysin O

Clostridium perfringens (C. perfringens) type A strains are the main cause of gas gangrene in humans and animals. Treatment of this lethal disease is limited, and the prognosis is not good. Alpha-toxin (CPA) and perfringolysin O (PFO) secreted by C. perfringens play irreplaceable roles in cytotoxicity to host cells, persistence in host tissues, and lethality of gas gangrene pathology. This work determined the influence of amentoflavone, a biflavonoid isolated from Selaginella tamariscina and other plants, on hemolysis and cytotoxicity mediated by CPA and PFO and evaluated the in vivo therapeutic effect on gas gangrene. Our data showed that amentoflavone could block the hemolysis and cytotoxicity induced by CPA and PFO in vitro, thereby mediating significant protection against mortality of infected mice in a mouse gas gangrene model, efficient bacterial clearance in tissues and alleviation of histological damage in vivo. Based on the above results, amentoflavone may be a potential candidate against C. perfringens infection by reducing CPA and PFO-mediated virulence.

Apoptosis induction and ERK/NF-κB inactivation are associated with magnolol-inhibited tumor progression in hepatocellular carcinoma in vivo

Although hepatitis B and/or hepatitis C virus were recognized as major risk factor for the development of hepatocellular carcinoma (HCC), certain occupational, environmental, and lifestyle factors also play key roles in HCC tumorigenesis. Moreover, in molecular signaling route, extracellular signal-regulated kinase (ERK)/nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling was found to be overexpressed and linked to poor prognosis in HCC. Thus, to identify possible nature compound that can suppress ERK/NF-κB may be benefit to HCC patient. Magnolol, a natural compound derived from herbal plant Magnolia officinalis, has been recognized as a liver protection and antitumor reagent. However, whether magnolol-inhibited HCC progression correlates with disruption of ERK/NF-κB signaling is remained unclear. In this studies, we performed SK-Hep1/luc2 HCC bearing animal model to investigate the anticancer efficacy and mechanism of magnolol on tumor progression. Tumor size and tumor growth rate were dramatically suppressed after treatment of magnolol. In addition, expression of phospho-ERK (p-ERK), NF-κB p65 (Ser536), and tumor progression-associated proteins, such as matrix metallopeptidase 9 (MMP-9), vascular endothelial growth factor (VEGF), X-linked inhibitor of apoptosis protein (XIAP), and CyclinD1 were all significantly decreased by magnolol. Most important, major extrinsic and intrinsic apoptosis signaling factors, including active caspase-8 and caspase-9 were both enhanced by magnolol. This study indicated that apoptosis induction through extrinsic/intrinsic pathways and blockage of ERK/NF-κB activation were associated with magnolol-inhibited tumor progression in HCC in vivo.

Amentoflavone Promotes Apoptosis in Non-Small-Cell Lung Cancer by Modulating Cancerous Inhibitor of PP2A

Non-small-cell lung cancer (NSCLC) is one of the most common human malignancies. Amentoflavone (AF) is one of bioflavonoid compounds isolated from Selaginella tamariscina Spring. This study was designed to examine the effect of AF on NSCLC. Our results indicated that AF decreased cell viability of both H1299 and H358 cells. Colony formation assay also showed that AF was able to suppress the anchorage-independent growth of NSCLC cells. AF also triggered cell cycle arrest by downregulating cyclin D1, CDK4, and CDK6. The pro-apoptotic activity of AF was confirmed by Hoechst staining and flow cytometry. The effect of AF on activation of caspase-3, upregulation of Bax, and downregulation of Bcl-2 was examined by western blot. The anti-growth and pro-apoptotic activities of AF were further validated in xenograft murine model. iTRAQ assay showed that cancerous inhibitor of PP2A (CIP2A) expression was markedly downregulated by AF treatment in H1299 cells. In addition, qRT-PCR and western blot also showed that AF was able to dose-dependently inhibit CIP2A expression. Meanwhile, the activity of protein phosphatase 2A (PP2A) was enhanced by AF treatment. The mRNA and protein expression of CIP2A as well as PP2A activity in xenograft tumor tissue were examined, which indicated that the in vivo anticancer activity of AF was associated with downregulation of CIP2A and reactivation of PP2A. Moreover, our results showed that the anti-growth and pro-apoptotic activities of AF were augmented by CIP2A knockdown and attenuated by ectopic CIP2A expression. Our results indicated that AF exhibited anticancer activity in NSCLC by targeting CIP2A. Anat Rec, 302:2201-2210, 2019. © 2019 American Association for Anatomy.

Amentoflavone Affects Epileptogenesis and Exerts Neuroprotective Effects by Inhibiting NLRP3 Inflammasome

Brain inflammation is one of the main causes of epileptogenesis, a chronic process triggered by various insults, including genetic or acquired factors that enhance susceptibility to seizures. Amentoflavone, a naturally occurring biflavonoid compound that has anti-inflammatory effects, exerts neuroprotective effects against nervous system diseases. In the present study, we aimed to investigate the effects of amentoflavone on epilepsy in vivo and in vitro and elucidate the underlying mechanism. The chronic epilepsy model and BV2 microglial cellular inflammation model were established by pentylenetetrazole (PTZ) kindling or lipopolysaccharide (LPS) stimulation. Cognitive dysfunction was tested by Morris water maze while hippocampal neuronal apoptosis was evaluated by immunofluorescence staining. The levels of nucleotide oligomerization domain-like receptor protein 3 (NLRP3) inflammasome complexes and inflammatory cytokines were determined using quantitative real-time polymerase chain reaction, Western blotting, immunofluorescence staining, and enzyme-linked immunosorbent assay. Amentoflavone reduced seizure susceptibility, minimized PTZ-induced cognitive dysfunction, and blocked the apoptosis of hippocampal neurons in PTZ-induced kindling mice. Amentoflavone also inhibited the activation of the NLRP3 inflammasome and decreased the levels of inflammatory cytokines in the hippocampus of PTZ-induced kindling mice. Additionally, amentoflavone could alleviate the LPS-induced inflammatory response by inhibiting the NLRP3 inflammasome in LPS-induced BV2 microglial cells. Our results indicated that amentoflavone affects epileptogenesis and exerts neuroprotective effects by inhibiting the NLRP3 inflammasome and, thus, mediating the inflammatory process in PTZ-induced kindling mice and LPS-induced BV2 microglial cells. Therefore, amentoflavone may be a potential treatment option for epilepsy.

Protein Kinase B and Extracellular Signal-Regulated Kinase Inactivation is Associated with Regorafenib-Induced Inhibition of Osteosarcoma Progression In Vitro and In Vivo

Osteosarcoma is the most common type of bone cancer. Multimodality treatment involving chemotherapy, radiotherapy and surgery is not effective enough to control osteosarcoma. Regorafenib, the oral multi-kinase inhibitor, has been shown to have positive efficacy on disease progression delay in chemotherapy resistant osteosarcoma patients. However anti-cancer effect and mechanism of regorafenib in osteosarcoma is ambiguous. Thus, the aim of this study is to investigate the efficacy and molecular mechanism of regorafenib on osteosarcoma in vitro and in vivo. Human osteosarcomas U-2 OS or MG-63 were treated with regorafenib, miltefosine (protein kinase B (AKT) inhibitor), or PD98059 (mitogen-activated protein/extracellular signal-regulated kinase (MEK) pathway inhibitor) for 24 or 48 h. Cell viability, apoptotic signaling transduction, tumor invasion, expression of tumor progression-associated proteins and tumor growth after regorafenib treatment were assayed by MTT 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, flow cytometry, transwell assay, Western blotting assay and in vivo animal experiment, respectively. In these studies, we also indicated that regorafenib suppressed cell growth by prompting apoptosis of osteosarcoma cells, which is mediated through inactivation of ERK and AKT signaling pathways. After regorafenib treatment, downregulation of related genes in invasion (vascular endothelial growth factor (VEGF) and matrix metallopeptidase 9 (MMP-9)), proliferation (CyclinD1) and anti-apoptosis (X-linked inhibitor of apoptosis protein (XIAP), myeloid cell leukemia-1 (MCL-1), and cellular FLICE (FADD-like IL-1β-converting enzyme)-inhibitory protein (C-FLIP)) were found. Moreover, upregulation of caspase-3 and caspase-8 cleavage were also observed. In sum, we suggest that regorafenib has potential to suppress osteosarcoma progression via inactivation of AKT and ERK mediated signaling pathway.

Apoptosis induction and AKT/NF-κB inactivation are associated with regroafenib-inhibited tumor progression in non-small cell lung cancer in vitro and in vivo

Non-small cell lung cancer (NSCLC) is a malignant lung cancer type with poor prognosis. NF-κB, the oncogenic transcription factor, has been recognized as an important mediator in progression of NSCLC. Regorafenib, a multikinase inhibitor, was demonstrated to inhibit tumor progression through suppression of ERK/NF-κB signaling in hepatocellular carcinoma cells in vitro and in vivo. However, whether regorafenib inhibit progression of NSCLC is ambiguous. Thus, the major purpose of present study was to evaluate anticancer efficacy and underlying mechanism of regorafenib on tumor progression in NSCLC in vitro and in vivo. CL-1-5-F4 cells were treated with regorafenib, NF-κB (QNZ) or AKT (LY294002) inhibitor for 24 or 48 h. Then, we performed cell viability assay, NF-κB reporter gene assay, transwell invasion assay and apoptosis related flow cytometry assay on cellular level to verify anti-cancer effect and mechanism of regorafenib. CL-1-5-F4 bearing animal model was treated with vehicle or regorafenib for 28 days. The therapeutic efficacy and mechanism of regorafenib in CL-1-5-F4 bearing animal model were investigated by tumor size evaluation, whole body computer tomography (CT) scan, Haemotoxylin and Eosin (H&E) stain and immunohistochemistry (IHC) stain. Our results demonstrated regorafenib significantly inhibited tumor growth and induced apoptosis through extrinsic/intrinsic pathways in NSCLC in vitro and in vivo. Furthermore, we also found the suppression of AKT/NF-κB signaling was required for regorafenib inhibited expression of progression-related and invasion-related proteins. Our finding indicated apoptosis induction and suppression of AKT/NF-κB signaling were associated with regorafenib-inhibited progression of NSCLC in vitro and in vivo.

Amentoflavone Effectively Blocked the Tumor Progression of Glioblastoma via Suppression of ERK/NF- κ B Signaling Pathway

Glioblastoma is the most common primary malignant tumor of the central nervous system, with an annual incidence of 5.26 per 100000 people. The clinical outcome of standard therapy and the survival rate remain poor; therefore, there is an unmet need for a new strategy to treat this lethal disease. Although amentoflavone was known to have anticancer potential in various types of cancers, its antiglioblastoma ability and mechanism remain unrecognized. We demonstrated that amentoflavone may suppress glioblastoma invasion and migration by transwell assay. Moreover, we established NF- κ B reporter gene system and used that for verifying NF- κ B inhibition efficacy of amentoflavone on in vitro and in vivo studies. Here, we indicated that amentoflavone not only diminished NF- κ B activation, but also reduced NF- κ B-mediated downstream oncogenes expression, such as MMP-2, MMP-9, XIAP, cyclinD1 and VEGF, which was elucidated by Western blot and immunohistochemistry (IHC). Tumor growth inhibition and NF- κ B reduction was found in the amentoflavone treatment group, which was revealed by the glioblastoma-bearing animal model. In this study, we also used ERK inhibitor and NF- κ B inhibitor (QNZ) to confirm whether the beneficial result of amentoflavone on glioblastoma was mainly regulated by blockage of ERK/NF- κ B signaling. In summary, ERK/NF- κ B signaling pathway has a role in the inhibition of tumor growth by amentoflavone in glioblastoma.

Chlorogenic Acid Attenuates Dextran Sodium Sulfate-Induced Ulcerative Colitis in Mice through MAPK/ERK/JNK Pathway

Objective

Observe the protective effect of chlorogenic acid on dextran sulfate-induced ulcerative colitis in mice and explore the regulation of MAPK/ERK/JNK signaling pathway.

Methods

Seventy C57BL/6 mice (half males and half females) were randomly divided into 7 groups, 10 in each group: control group (CON group), UC model group (UC group), and sulfasalazine-positive control group (SASP group), chlorogenic acid low dose group (CGA-L group), chlorogenic acid medium dose group (CGA-M group), chlorogenic acid high dose group (CGA-H group), and ERK inhibitor + chlorogenic acid group (E+CGA group). The effects of chlorogenic acid on UC were evaluated by colon mucosa damage index (CMDI), HE staining, immunohistochemistry, ELISA, and Western blot. The relationship between chlorogenic acid and MAPK/ERK/JNK signaling pathway was explored by adding ERK inhibitor.

Results

The UC models were established successfully by drinking DSS water. Chlorogenic acid reduces DSS-induced colonic mucosal damage, inhibits DSS-induced inflammation, oxidative stress, and apoptosis in colon, and reduces ERK1/2, p -ERK, p38, p-p38, JNK, and p-JNK protein expression. ERK inhibitor U0126 reversed the protective effect of chlorogenic acid on colon tissue.

Conclusion

Chlorogenic acid can alleviate DSS-induced ulcerative colitis in mice, which can significantly reduce tissue inflammation and apoptosis, and its mechanism is related to the MAPK/ERK/JNK signaling pathway.

Fluoxetine Induces Apoptosis through Extrinsic/Intrinsic Pathways and Inhibits ERK/NF-κB-Modulated Anti-Apoptotic and Invasive Potential in Hepatocellular Carcinoma Cells In Vitro

The aim of the present study was to verify the effects of fluoxetine on dysregulation of apoptosis and invasive potential in human hepatocellular carcinoma (HCC) SK-Hep1 and Hep3B cells. Cells were treated with different concentrations of fluoxetine for different times. MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assays were used for testing the effects of fluoxetine on cell viability. The regulation of apoptosis signaling, and anti-apoptotic, proliferation, and metastasis-associated proteins after fluoxetine treatment were assayed by flow cytometry and Western blotting assay. The detection of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation after fluoxetine treatment was performed by NF-κB reporter gene assay. The results demonstrated that fluoxetine significantly reduced cell viability, cell migration/invasion, NF-κB, extracellular signal-regulated kinases (ERK) activation, and expression of anti-apoptotic (Cellular FLICE (FADD-like IL-1β-converting enzyme)-inhibitory protein (C-FLIP), Myeloid cell leukemia-1 (MCL-1), X-Linked inhibitor of apoptosis protein (XAIP), and Survivin), proliferation (Cyclin-D1), angiogenesis (vascular endothelial growth factor (VEGF)), and metastasis-associated proteins (matrix metalloproteinase-9 (MMP-9)). Fluoxetine also significantly induced apoptosis, unregulated extrinsic (activation of first apoptosis signal protein and ligand (Fas/FasL), and caspase-8) and intrinsic (loss of mitochondrial membrane potential (ΔΨm) pathways and increased Bcl-2 homologous antagonist killer (BAK) apoptosis signaling. Taken together, these results demonstrated that fluoxetine induced apoptosis through extrinsic/intrinsic pathways and diminished ERK/NF-κB-modulated anti-apoptotic and invasive potential in HCC cells in vitro.