The anti-lung cancer activities of steroidal saponins of P. polyphylla Smith var. chinensis (Franch.) Hara through enhanced immunostimulation in experimental Lewis tumor-bearing C57BL/6 mice and induction of apoptosis in the A549 cell line

The role of Rhizoma Paridis saponins on anti-cancer: The potential mechanism and molecular targets

Cancer is a disease characterized by uncontrolled cell proliferation, leading to excessive growth and invasion that can spread to other parts of the body. Traditional Chinese medicine has made new advancements in the treatment of cancer, providing new perspectives and directions for cancer treatment. Rhizoma Paridis is a widely used Chinese herbal medicine with documented anti-cancer effects dating back to ancient times. Modern research has shown that Rhizoma Paridis saponins (RPS) have various pharmacological activities. RPS can inhibit cancer in multiple ways, such as suppressing tumor growth, inducing cell cycle arrest, promoting cell apoptosis, enhancing cell autophagy, inducing ferroptosis, reducing inflammation, inhibiting angiogenesis, as well as inhibiting metastasis and invasion, and these findings demonstrate the potent anti-cancer activity of RPS. Polyphyllin I, polyphyllin II, polyphyllin VI, and polyphyllin VII have been widely reported as the main active ingredients with anti-cancer properties. Polyphyllin D, polyphyllin E, and polyphyllin G have also been confirmed to possess strong anti-cancer activity in recent years. Therefore, this review dives deep into the molecular mechanisms underlying the anti-cancer effects of RPS to serve as a valuable reference for future scientific research and their potential applications in cancer treatment.

Evaluation of the effect of GSK-3β on liver cancer based on the PI3K/AKT pathway

The PI3K/AKT/GSK-3β signaling pathway plays a pivotal role in numerous physiological and pathological processes, including cell proliferation, apoptosis, differentiation, and metabolic regulation. Aberrant activation of the PI3K/AKT pathway is intricately linked to development of tumor. GSK-3β, belonging to the serine/threonine protein kinase family, is crucial in the pathogenesis of liver cancer. As a key rate-limiting enzyme in the glucose metabolism pathway, GSK-3β significantly impacts the growth, proliferation, metastasis, and apoptosis of liver cancer cells. It is also implicated in chemotherapy resistance. Elevated expression of GSK-3β diminishes the sensitivity of liver cancer cells to chemotherapeutic agents, thereby playing a substantial role in the development of drug resistance. Consequently, targeting of GSK-3β, particularly within the PI3K/AKT signaling pathway, is regarded as a promising therapeutic strategy for liver cancer. The precise identification and subsequent modulation of this pathway represent a substantial potential for innovative clinical interventions in the management of liver cancer.

Critical review on anti-inflammation effects of saponins and their molecular mechanisms

This review highlights the increasing interest in one of the natural compounds called saponins, for their potential therapeutic applications in addressing inflammation which is a key factor in various chronic diseases. It delves into the molecular mechanisms responsible for the anti-inflammatory effects of these amphiphilic compounds, prevalent in plant-based foods and marine organisms. Their structures vary with soap-like properties influencing historical uses in traditional medicine and sparking renewed scientific interest. Recent research focuses on their potential in chronic inflammatory diseases, unveiling molecular actions such as NF-κB and MAPK pathway regulation and COX/LOX enzyme inhibition. Saponin-containing sources like Panax ginseng and soybeans suggest novel anti-inflammatory therapies. The review explores their emerging role in shaping the gut microbiome, influencing composition and activity, and contributing to anti-inflammatory effects. Specific examples, such as Panax notoginseng and Gynostemma pentaphyllum, illustrate the intricate relationship between saponins, the gut microbiome, and their collective impact on immune regulation and metabolic health. Despite promising findings, the review emphasizes the need for further research to comprehend the mechanisms behind anti-inflammatory effects and their interactions with the gut microbiome, underscoring the crucial role of a balanced gut microbiome for optimal health and positioning saponins as potential dietary interventions for managing chronic inflammatory conditions.

Identification, molecular characterization and phylogenetic analysis of a novel nucleorhabdovirus infecting Paris polyphylla var. yunnanensis

A novel betanucleorhabdovirus infecting Paris polyphylla var. yunnanensis, tentatively named Paris yunnanensis rhabdovirus 1 (PyRV1), was recently identified in Yunnan Province, China. The infected plants showed vein clearing and leaf crinkle at early stage of infection, followed by leaf yellowing and necrosis. Enveloped bacilliform particles were observed using electron microscopy. The virus was mechanically transmissible to Nicotiana bethamiana and N. glutinosa. The complete genome of PyRV1 consists of 13,509 nucleotides, the organization of which was typical of rhabdoviruses, containing six open reading frames encoding proteins N-P-P3-M-G-L on the anti-sense strand, separated by conserved intergenic regions and flanked by complementary 3'-leader and 5'-trailer sequences. The genome of PyRV1 shared highest nucleotide sequence identity (55.1%) with Sonchus yellow net virus (SYNV), and the N, P, P3, M, G, and L proteins showed 56.9%, 37.2%, 38.4%, 41.8%, 56.7%, and 49.4% amino acid sequence identities with respective proteins of SYNV, suggesting RyRV1 belongs to a new species of the genus Betanucleorhabdovirus.

Lung cancer immunotherapy: progress, pitfalls, and promises

Lung cancer is the primary cause of mortality in the United States and around the globe. Therapeutic options for lung cancer treatment include surgery, radiation therapy, chemotherapy, and targeted drug therapy. Medical management is often associated with the development of treatment resistance leading to relapse. Immunotherapy is profoundly altering the approach to cancer treatment owing to its tolerable safety profile, sustained therapeutic response due to immunological memory generation, and effectiveness across a broad patient population. Different tumor-specific vaccination strategies are gaining ground in the treatment of lung cancer. Recent advances in adoptive cell therapy (CAR T, TCR, TIL), the associated clinical trials on lung cancer, and associated hurdles are discussed in this review. Recent trials on lung cancer patients (without a targetable oncogenic driver alteration) reveal significant and sustained responses when treated with programmed death-1/programmed death-ligand 1 (PD-1/PD-L1) checkpoint blockade immunotherapies. Accumulating evidence indicates that a loss of effective anti-tumor immunity is associated with lung tumor evolution. Therapeutic cancer vaccines combined with immune checkpoint inhibitors (ICI) can achieve better therapeutic effects. To this end, the present article encompasses a detailed overview of the recent developments in the immunotherapeutic landscape in targeting small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). Additionally, the review also explores the implication of nanomedicine in lung cancer immunotherapy as well as the combinatorial application of traditional therapy along with immunotherapy regimens. Finally, ongoing clinical trials, significant obstacles, and the future outlook of this treatment strategy are also highlighted to boost further research in the field.

Therapeutic effects on cancer of the active ingredients in rhizoma paridis

Cancer is a major threat to human health, with high mortality and a low cure rate, continuously challenging public health worldwide. Extensive clinical application of traditional Chinese medicine (TCM) for patients with poor outcomes of radiotherapy and chemotherapy provides a new direction in anticancer therapy. Anticancer mechanisms of the active ingredients in TCM have also been extensively studied in the medical field. As a type of TCM against cancer, Rhizoma Paridis (Chinese name: Chonglou) has important antitumor effects in clinical application. The main active ingredients of Rhizoma Paridis (e.g., total saponins, polyphyllin I, polyphyllin II, polyphyllin VI, and polyphyllin VII) have shown strong antitumor activities in various cancers, such as breast cancer, lung cancer, colorectal cancer, hepatocellular carcinoma (HCC), and gastric cancer. Rhizoma Paridis also has low concentrations of certain other active ingredients with antitumor effects, such as saponins polyphyllin E, polyphyllin H, Paris polyphylla-22, gracillin, and formosanin-C. Many researchers have studied the anticancer mechanism of Rhizoma Paridis and its active ingredients. This review article describes research progress regarding the molecular mechanism and antitumor effects of the active ingredients in Rhizoma Paridis, suggesting that various active ingredients in Rhizoma Paridis may be potentially therapeutic against cancer.

Novel archetype in cancer therapeutics: exploring prospective of phytonanocarriers

This paper reports various types of cancer, their incidence, and prevalence all over the globe. Along with the discovery of novel natural drugs for cancer treatment, these present a promising option which are eco-friendly, safe, and provide better acceptability in comparison to synthetic agents that carries multiple side effects. This paper provides an idea about various nanocarriers and phytochemicals, along with how their solubility and bioavailability can be enhanced in nanocarrier system. This report combines the data from various literature available on public domain including PubMed on research articles, reviews, and along with report from various national and international sites. Specialized metabolites (polyphenols, alkaloids, and steroids etc) from medicinal plants are promising alternatives to existing drugs. Studies have suggested that the treatment of cancer using plant products could be an alternative and a safe option. Studies have shown with the several cell lines as well as animal models, that phytomolecules are important in preventing/treating cancer. Phytochemicals often outperform chemical treatments by modulating a diverse array of cellular signaling pathways, promoting cell cycle arrest, apoptosis activation, and metastatic suppression, among others. However, limited water solubility, bioavailability, and cell penetration limit their potential clinical manifestations. The development of plant extract loaded nanostructures, rendering improved specificity and efficacy at lower concentrations could prove effective. Nanocarriers, such as liposomes, nanostructured lipids, polymers, and metal nanoparticles, have been tested for the delivery of plant products with enhanced effects. Recent advances have achieved improvement in the the stability, solubility, bioavailability, circulation time, and target specificity by nanostructure-mediated delivery of phytochemicals. Nanoparticles have been considered and attempted as a novel, targeted, and safe option. Newer approaches such as phyto-nanocarriers with carbohydrates, lignin, and polymers have been considered even more selective and effective modes of drug delivery in biomedical or diagnostic applications.

Anticancer Effect of Polyphyllin I in Suppressing Stem Cell-Like Properties of Hepatocellular Carcinoma via the AKT/GSK-3β/β-Catenin Signaling Pathway

Polyphyllin I (PPI), also called Chong Lou saponin I, is a steroidal saponin isolated from the rhizome of Paris polyphylla. PPI has been demonstrated to have strong anticancer activity. However, its effect on the stemness of liver cancer stem cells (LCSCs) is not completely understood. Herein, we aimed to investigate the effect of PPI on the stem cell-like features of LCSCs and hepatocellular carcinoma (HCC). LCSCs were enriched in a serum-free medium and treated with PPI, sorafenib (Sora), or PPI and Sora. Several endpoints, including spheroid formation and differentiation, cell proliferation, surface markers of LCSCs, PPI binding targets, and stemness-associated protein expression, were evaluated. Immunofluorescence staining, quantitative real-time polymerase chain reaction, siRNA transfection, and coimmunoprecipitation ubiquitination assays were conducted for in-depth mechanistic studies. Evaluation of in vivo antitumor efficacy demonstrated that PPI effectively inhibited the proliferation of liver cancer cells and the self-renewal and differentiation of LCSCs. Flow cytometry indicated that PPI suppressed the expression of the stem cell surface markers EpCAM and CD13. Molecular docking showed a high affinity between PPI and proteins of the Wnt/β-catenin signaling pathway, including AKT, GSK-3β, and β-catenin, with the binding energies of -5.51, -5.32, and -5.40 kcal/mol, respectively, which suggested that PPI might regulate the Wnt/β-catenin signaling pathway to affect the stem cell-like properties of HCC. Further ex vivo experiments implied that PPI activated the AKT/GSK-3β-mediated ubiquitin proteasomal degradation of β-catenin and subsequently attenuated the prooncogenic effect of LCSCs. Finally, the anticancer property of PPI was confirmed in vivo. It was found that PPI inhibited the tumor growth in an HCC cell line xenograft model. Taken together, molecular docking analysis and experimental data highlighted the novel function of PPI in suppressing the stem cell-like characteristics of LCSCs via the AKT/GSK-3β/β-catenin signaling pathway.

High fat diet-induced hyperlipidemia and tissue steatosis in rabbits through modulating ileal microbiota

High-fat diet (HFD) and overnutrition are important starting factors that may alter intestinal microbiota, lipid metabolism, and systemic inflammation. However, there were few studies on how intestinal microbiota contributes to tissue steatosis and hyperlipidemia. Here, we investigated the effect of lipid metabolism disorder-induced inflammation via toll-like receptor 2 (TLR-2), toll-like receptor 4 (TLR-4), and nuclear factor-κB (NF-κB) pathways at the intestinal level in response to HFD. Twenty 80-day-old male New Zealand White rabbits were randomly divided into the normal diet group (NDG) and the high-fat diet group (HDG) for 80 days. Growth performance, blood biochemical parameters, lipid metabolism, inflammation, degree of tissue steatosis, and intestinal microbial composition were measured. HFD increased the relative abundance of Christensenellaceae_R_7_group, Marvinbryantia, Akkermansia etc., with a reduced relative abundance of Enterorhabdus and Lactobacillus. Moreover, HFD caused steatosis in the liver and abdominal fat and abnormal expression of some genes related to lipid metabolism and tight junction proteins. The TLR-2, TLR-4, NF-κB, TNF-α, and IL-6 were confirmed by overexpression with downregulation of IL-10. Serum biochemical indices (TG, TCHO, LDL-C, and HDL-C) were also increased, indicating evidence for the development of the hyperlipidemia model. Correlation analysis showed that this microbial dysbiosis was correlated with lipid metabolism and inflammation, which were associated with the intestinal tract's barrier function and hyperlipidemia. These results provide an insight into the relationship between HFD, the intestinal microbiota, intestinal barrier, tissue inflammation, lipid metabolism, and hyperlipidemia. KEY POINTS: • High-fat diet leads to ileal microbiota disorders • Ileal microbiota mediates local and systemic lipid metabolism disorders and inflammation • There is a specific link between ileal microbiota, histopathology, and hyperlipidemia.

Q-marker identification of Paris polyphylla var. yunnanensis (Franch.) Hand.-Mazz. in pulmonary metastasis of liver cancer mice

ETHNOPHARMACOLOGICAL RELEVANCE

Rhizoma Paridis saponins (RPS) as the mainly active components of Paris polyphylla var. yunnanensis (Franch.) Hand.-Mazz., possess tumor therapeutic potential. However, the anti-tumor material basis of RPS in liver cancer pulmonary metastasis remains poorly understood. The objective of this study was to identify the distribution and anti-cancer effects of RPS in liver cancer pulmonary metastatic model.

MATERIALS AND METHODS

In this study, a mouse liver cancer pulmonary metastasis model was established to determine the distribution of different saponins in the tissues by UPLC-MS and plasma protein binding rate.

RESULTS

As a result, RPS prolonged the survival time and inhibited the pulmonary metastasis in H22 injected mice through its underlying mechanism. UPLC-MS identified saponins from RPS such as PVII, PH, PVI, PII, gracillin and PI in tissues, which may be regarded as the Q-markers in RPS. Surprisingly, the concentration of PI, PII and gracillin as diosgenyl saponins was higher than that of pennogenyl saponins in the liver and lung. Besides, plasma protein binding rate of PII was higher than that of PVII.

CONCLUSION

These findings suggested that PVII, PH, PVI, PI, PII and gracillin are regarded as the Q-markers of RPS in liver cancer pulmonary metastasis. The concentration of PI, PII and gracillin as diosgenyl saponins was higher than that of pennogenyl saponins in the liver and lung. It would be helpful for understanding the importance of RPS with anticancer activities in the future.

Bioactive secondary metabolites in Paris polyphylla Sm. and their biological activities: A review

Paris polyphylla Sm. is an important medicinal plant used to treat a variety of diseases through traditional medicine systems such as Ayurveda, Tibetan traditional medicines, Chinese traditional medicines, and others around the world. The IUCN red list has designated it as "vulnerable" due to a decline in wild population by over-exploitation, habitat degradation, illegal collection for trade and traditional use. This review paper aims to summarize the bioactive secondary metabolites in Paris polyphylla. Paris saponins or steroidal saponins are the main bioactive chemical constituents from this plant that account for more than 80% of the total compounds. For instance, polyphyllin D, diosgenin, paris saponins I, II, VI, VII, and H are steroidal saponins having anticancer activity comparable to synthetic anticancer medicines. Antioxidant, anticancer, anti-leishmaniasis, antibacterial, antifungal, anthelmintic, antityrosinase, and antiviral effects of extracts and pure compounds were also demonstrated in vivo and in vitro. In conclusion, this review summarizes the bioactive components from the P. polyphylla which will be useful to researchers and scientists, and for the development of potential drugs.

Total flavonoids of Taraxacum mongolicum inhibit non-small cell lung cancer by regulating immune function

ETHNOPHARMACOLOGICAL RELEVANCE

Taraxacum mongolicum Hand.-Mazz. has been used in lung cancer treatment in Chinese medicine. However, its specific mechanism of action has not yet been reported, and developing pharmaceutical anti-cancer resources is important. Here, we aimed to elucidate the anti-tumor effects of dandelion in vitro and in vivo and assess its effects on immune function in lung cancer patients.

AIM OF THE STUDY

In the present study, we mainly observed the therapeutic effects of total flavonoids from Taraxacum mongolicum Hand.-Mazz. (TFTM) on non-small cell lung cancer and its influence on the body's immune function.

MATERIALS AND METHODS

In vitro experiments on A549 and H1299 cells were performed using the CCK8 method; the proliferation and migration of cells were observed to investigate the wound healing effects of TFTM, and flow cytometry was used to detect the apoptotic rate of TFTM on lung cancer cells. In vivo experiments were preformed to establish a non-small cell lung cancer mouse model using subcutaneously transplanted Lewis cells, and the body weight and tumor growth of the mice were recorded. Hematoxylin and eosin staining was performed for tumor tissue to assess pathological changes. The thymus, spleen, and lungs were isolated for to calculate organ index. The CD4+, CD8+, and CD4+/CD8+ levels were detected in mouse spleen using flow cytometry, and IL-2, IL-3, IFN-γ, and TNF-α levels were determined in serum using enzyme-linked immunosorbent assay. Expressions of IL-2, IL-3, IFN-γ, and TNF-α were detected using quantitative real-time PCR in tumor tissues, and Ki67 expression was observed by immunofluorescence.

RESULTS

At 24 h, TFTM (100 and 200 μg/mL) had the best inhibitory effect on the proliferation of A549 and H1299 cells. The cell migration rate significantly reduced (P < 0.01), and the tumor inhibition rate increased (P < 0.01) and promoted apoptosis (P < 0.01). The mouse thymus index significantly increased (P < 0.05) and mouse spleen index reduced (P < 0.05). The CD4+, CD8+, and CD4+/CD8+ levels in Lewis lung cancer mouse model increased, as did the levels of IL-2, IL-3, IFN-γ, and TNF-α in the serum and tumor of mice; Ki67 expression in tumor tissues significantly reduced (P < 0.01).

CONCLUSION

TFTM has an inhibitory effect on lung cancer. The mechanism may be that it improves the host's protective immune response by having a milder tumor growth inhibitory effect than cyclophosphamide.

A new homo-aro-cholestane glycoside from the rhizome of Paris polyphylla var. chinensis

A new homo-aro-cholestane glycoside parispolyside H, along with nine known compounds, were isolated from 75% ethanolic extract of the rhizome of Paris polyphylla var. chinensis. Their chemical structures were elucidated on the basic of analysis of detailed spectroscopic and physicochemical properties. In addition, the isolated compounds (1, 6-9) were evaluated for their cytotoxic activity against HepG2 human liver cancer cell lines. Among them, four known compounds (6-9) showed cytotoxicity with IC₅₀ values ranging from 0.41 to 3.6 μM.

Review On Documented Medicinal Plants Used For The Treatment Of Cancer

Background:

Cancer is a frightful disease and it is the second leading cause of death worldwide. Naturally derived compounds are gaining interest of research workers as they have less toxic side effects as compared to currently used treatments such as chemotherapy. Plants are the pool of chemical compounds which provides a promising future for research on cancer.

Objective:

This review paper provides updated information gathered on medicinal plants and isolated phytoconstituents used as anticancer agents and summarises the plant extracts and their isolated chemical constituents exhibiting anticancer potential on clinical trials.

Methods:

An extensive bibliographic investigation was carried out by analysing worldwide established scientific databases like SCOPUS, PUBMED, SCIELO, ScienceDirect, Springerlink, Web of Science, Wiley, SciFinder and Google Scholar etc. In next few decades, herbal medicine may become a new epoch of medical system.

Results:

Many researches are going on medicinal plants for the treatment of cancer but it is a time to increase further experimental studies on plant extracts and their chemical constituents to find out their mechanism of action at molecular level.

Conclusion:

The article may help many researchers to start off further experimentation that might lead to the drugs for the cancer treatment.

The Fruits of Paris polyphylla Inhibit Colorectal Cancer Cell Migration Induced by Fusobacterium nucleatum-Derived Extracellular Vesicles

Colorectal cancer (CRC) is one of the most common cancers worldwide. Gut microbiota are highly associated with CRC, and Fusobacterium nucleatum was found to be enriched in CRC lesions and correlated with CRC carcinogenesis and metastases. Paris polyphylla is a well-known herbal medicine that showed anticancer activity. The present study demonstrates that P. polyphylla inhibited the growth of CRC cells. In addition, treating with active compounds pennogenin 3-O-beta-chacotrioside and polyphyllin VI isolated from P. polyphylla inhibited the growth of F. nucleatum. We also found that extracellular vesicles (EVs) released from F. nucleatum could promote mitochondrial fusion and cell invasion in CRC cells, whereas active components from P. polyphylla could dampen such an impact. The data suggest that P. polyphylla and its active ingredients could be further explored as potential candidates for developing complementary chemotherapy for the treatment of CRC.

Qizhen capsule inhibits colorectal cancer by inducing NAG-1/GDF15 expression that mediated via MAPK/ERK activation

ETHNOPHARMACOLOGICAL RELEVANCE

Qizhen capsule (QZC) is a traditional Chinese medicine (TCM) preparation that has been widely used in clinical practice and exerts promising therapeutic effects against breast, lung, and gastric cancers. However, studies have not reported whether QZC inhibits colorectal cancer (CRC) development and progression. Meanwhile, the underlying molecular mechanisms of its anticancer activity have not been studied.

AIM OF THE STUDY

To investigate the anticancer effects of QZC on CRC and the possible underlying molecular mechanisms of QZC in vitro and in vivo.

MATERIALS AND METHODS

The MTT assay and flow cytometry were used to determine the viability and apoptosis of HCT116 and HT-29 cancer cells. A xenograft nude mouse model was used to study the antitumor effects of QZC in vivo. Western blotting was performed to determine the expression of key proteins responsible for the molecular mechanisms elicited by QZC. Immunofluorescence staining was performed to detect the expression of nonsteroidal anti-inflammatory drug (NSAID)-activated gene-1 or growth differentiation factor-15 (NAG-1/GDF15). Small interfering RNAs (siRNAs) were used to silence NAG-1/GDF15 in cells.

RESULTS

In this study, QZC significantly reduced the viability of HCT116 and HT-29 cells and induced apoptosis in dose- and time-dependent manners, but displayed much less toxicity toward normal cells. QZC-induced apoptosis in HCT116 cells was accompanied by the deregulation of the expression of the Bcl-2, Bax, PARP, caspase-3, and caspase-9 proteins. Furthermore, QZC induced NAG-1/GDF15 expression in HCT116 cells, while silencing of NAG-1/GDF15 attenuated QZC-induced apoptosis and cell death. Next, QZC increased the phosphorylation of mTOR, AMPK, p38, and MAPK/ERK in HCT116 cells. We then demonstrated that QZC-induced apoptosis and NAG-1/GDF15 upregulation were mediated by MAPK/ERK activation. Moreover, QZC significantly inhibited HCT116 xenograft tumor growth in nude mice, which was accompanied by NAG/GDF15 upregulation and MAPK/ERK activation. QZC also prevented 5-FU-induced weight loss or cachexia in tumor-bearing mice. The expression of Ki67 and PCNA was suppressed, while cleaved caspase-3 level and TUNEL staining were increased in the tumor sections from QZC-treated mice compared to the control.

CONCLUSION

QZC is a novel anticancer agent for CRC that targets NAG-1/GDF15 via the MAPK/ERK signaling pathway.

Saponins in Cancer Treatment: Current Progress and Future Prospects

Saponins are steroidal or triterpenoid glycoside that is distinguished by the soap-forming nature. Different saponins have been characterized and purified and are gaining attention in cancer chemotherapy. Saponins possess high structural diversity, which is linked to the anticancer activities. Several studies have reported the role of saponins in cancer and the mechanism of actions, including cell-cycle arrest, antioxidant activity, cellular invasion inhibition, induction of apoptosis and autophagy. Despite the extensive research and significant anticancer effects of saponins, there are currently no known FDA-approved saponin-based anticancer drugs. This can be attributed to a number of limitations, including toxicities and drug-likeness properties. Recent studies have explored options such as combination therapy and drug delivery systems to ensure increased efficacy and decreased toxicity in saponin. This review discusses the current knowledge on different saponins, their anticancer activity and mechanisms of action, as well as promising research within the last two decades and recommendations for future studies.

Anticancer Plants: A Review of the Active Phytochemicals, Applications in Animal Models, and Regulatory Aspects

The rising burden of cancer worldwide calls for an alternative treatment solution. Herbal medicine provides a very feasible alternative to western medicine against cancer. This article reviews the selected plant species with active phytochemicals, the animal models used for these studies, and their regulatory aspects. This study is based on a meticulous literature review conducted through the search of relevant keywords in databases, Web of Science, Scopus, PubMed, and Google Scholar. Twenty plants were selected based on defined selection criteria for their potent anticancer compounds. The detailed analysis of the research studies revealed that plants play an indispensable role in fighting different cancers such as breast, stomach, oral, colon, lung, hepatic, cervical, and blood cancer cell lines. The in vitro studies showed cancer cell inhibition through DNA damage and activation of apoptosis-inducing enzymes by the secondary metabolites in the plant extracts. Studies that reported in vivo activities of these plants showed remarkable results in the inhibition of cancer in animal models. Further studies should be performed on exploring more plants, their active compounds, and the mechanism of anticancer actions for use as standard herbal medicine.

Wedelolactone-Loaded Micelles Ameliorate Doxorubicin-Induced Oxidative Injury in Podocytes by Improving Permeability and Bioavailability

Wedelolactone (WED) is commonly used for the treatment of doxorubicin (DOX)-induced kidney damage, but its efficacy is limited by its poor solubility and bioavailability. In this study, we developed a novel delivery system of WED-loaded micelles (WED-M) with Solutol^® HS15 and lecithin at an optimized ratio of 7:3 to improve the poor permeability and bioavailability of WED and to enhance its efficacy. The spherically shaped WED-M (particle size: 160.5 ± 3.4 nm; zeta potential: −30.1 ± 0.9 mV; entrapment efficiency: 94.41 ± 1.64%; drug loading: 8.58 ± 0.25%; solubility: 1.89 ± 0.06 mg/ml) has continuous stability over 14 days and a sustained release profile. The permeability of WED-M in Caco-2 cells indicated a significant 1.61-fold higher Papp AP to BL ratio than WED alone. Additionally, pharmacokinetic evaluation of WED-M demonstrated that the bioavailability of WED was increased 2.78-fold. Both HE staining and transmission electron microscopy showed an obvious improvement of pathological damage in WED-M treatment. Moreover, WED-M significantly enhanced the ROS level in mice and MPC5 podocytes. We concluded that using this micelle delivery system for WED could improve its permeability and bioavailability to attenuate DOX-induced oxidative injury in podocytes. This study provided important information on the fact that the micelle delivery system, WED-M, showed a significant improvement of renal damage.

Determination of Inorganic Elements in the Rhizome of Paris polyphylla Smith Var. chinensis (Franch.) Hara by Using Inductively Coupled Plasma Mass Spectrometry

The objective of this study was to investigate the concentrations of inorganic elements in the rhizome of Paris polyphylla Smith var. chinensis (Franch.) Hara of different planting years and cultivation conditions. Twenty-five inorganic elements including Al, As, B, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, P, Pb, Se, Sr, Ti, V, and Zn in the rhizome were determined by using inductively coupled plasma mass spectrometry (ICP-MS). The analytical method was validated by measuring several parameters including linearity, correlation coefficient, limit of detection (LOD), limit of quantification (LOQ), and recovery. The linear working ranges were three, 0-300 μg/L, 0-500 μg/L, and 0-1000 μg/L, and the correlation coefficients (r) values were higher than 0.998. LOD varied from 0.001 μg/L (Be) to 11.957 μg/L (P), and LOQ varied from 0.003 μg/L (Be) to 35.870 μg/L (P). The recoveries spanned from 95.2 (Co) to 105.3% (Pb). Validation parameters showed the possibility of using whole of the sample preparation procedures used in this study. Based on the determined results, it is indicated that the toxic elements As, Cd, and Pb had no ingestion risk. The planting years and cultivation conditions had significant effects on the concentrations of inorganic elements of P. polyphylla var. chinensis. The concentrations of inorganic elements in cultivated samples were different from those in wild samples. The results can provide useful theoretical basis for the quality control and rational use of P. polyphylla var. chinensis.

Paris Polyphylla Inhibits Colorectal Cancer Cells via Inducing Autophagy and Enhancing the Efficacy of Chemotherapeutic Drug Doxorubicin

Colorectal cancer is one of the most common cancers worldwide and chemotherapy is the main approach for the treatment of advanced and recurrent cases. Developing an effective complementary therapy could help to improve tumor suppression efficiency and control adverse effects from chemotherapy. Paris polyphylla is a folk medicine for treating various forms of cancer, but its effect on colorectal cancer is largely unexplored. The aim of the present study is to investigate the tumor suppression efficacy and the mechanism of action of the ethanolic extract from P. polyphylla (EEPP) in DLD-1 human colorectal carcinoma cells and to evaluate its combined effect with chemotherapeutic drug doxorubicin. The data indicated that EEPP induced DLD-1 cell death via the upregulation of the autophagy markers, without triggering p53- and caspase-3-dependent apoptosis. Moreover, EEPP treatment in combination with doxorubicin enhanced cytotoxicity in these tumor cells. Pennogenin 3-O-beta-chacotrioside and polyphyllin VI were isolated from EEPP and identified as the main candidate active components. Our results suggest that EEPP deserves further evaluation for development as complementary chemotherapy for colorectal cancer.

Advances in the antitumor activities and mechanisms of action of steroidal saponins

The steroidal saponins are one of the saponin types that exist in an unbound state and have various pharmacological activities, such as anticancer, anti-inflammatory, antiviral, antibacterial and nerves-calming properties. Cancer is a growing health problem worldwide. Significant progress has been made to understand the antitumor effects of steroidal saponins in recent years. According to reported findings, steroidal saponins exert various antitumor activities, such as inhibiting proliferation, inducing apoptosis and autophagy, and regulating the tumor microenvironment, through multiple related signaling pathways. This article focuses on the advances in domestic and foreign studies on the antitumor activity and mechanism of actions of steroidal saponins in the last five years to provide a scientific basis and research ideas for further development and clinical application of steroidal saponins.

Antitumor and anti-metastatic mechanisms of Rhizoma paridis saponins in Lewis mice

Lung cancer is one of the most common causes of death in the world. Rhizoma paridis saponins (RPS) have been found to show inhibition of pulmonary adenoma in previous research. However, the detailed mechanisms of RPS from a holistic view have not been established. In this study, Lewis pulmonary adenoma mice were successfully established to analyze the pathways involved in RPS intervening tumor formation and progression. As a result, RPS inhibited levels of cytokines or receptors such as VEGFD, VEGFR3, RAGE, IL6R, IL17BR, and CXCL16 which were regarded as the initiators induced tumor cell proliferation, adhesion, angiogenesis, and invasion. Meanwhile, RPS raised the content of SOD and CAT enzymes and thereby inhibited the aberrantly active NF-κB, and phosphorylation of PI3K/Akt and MAPK (including p38, Erk1/2, and JNK) signaling pathways. Soon after, RPS changed mRNA expression of nuclear factors containing NF-κB, HIF-1A, STAT3, and Jun, and consequentially suppressed the expression of angiogenesis, lymphangiogenesis, adhesion, inflammation, and invasion enzymes. In conclusion, this research provided a holistic view to understand the multi-target antitumor mechanisms of RPS which promoted the application of RPS in the future.

S-allylmercaptocysteine suppresses the growth of human gastric cancer xenografts through induction of apoptosis and regulation of MAPK and PI3K/Akt signaling pathways

Gastric cancer remains as a common lethal malignancy worldwide. Developing novel anti-gastric cancer drugs with minimal side effects is necessary to address this public health issue. S-allylmercaptocysteine (SAMC), one of the water-soluble organosulfur garlic derivatives, has been demonstrated as a suppressive agent against tumors. In this study, we examined the effect of SAMC on human gastric carcinoma growth in vivo and explored the underlying mechanism. Human gastric cancer SGC-7901 cells were inoculated subcutaneously in BALB/c nude mice. When xenograft tumors reached about 100 mm³, mice were treated with SAMC for 30 days. We observed that SAMC administration in mice effectively delayed the growth of SGC-7901 xenografts without signs of toxicity. TUNEL staining confirmed that the tumors from SAMC-treated mice exhibited a markedly higher apoptotic index. Mechanistic studies suggested that this activity may arise from its effects on the caspase activation and modulation of MAPK and PI3K/Akt signaling pathways. Taken together, these data support development of SAMC as a potential agent for gastric cancer therapy.

Polyphyllin I induces G2/M phase arrest and apoptosis in U251 human glioma cells via mitochondrial dysfunction and the JNK signaling pathway

Glioblastoma is the most aggressive brain tumor, and its prognosis remains poor. Therefore, novel therapeutic strategies are needed for glioma therapy. Polyphyllin I (PPI), a bioactive constituent extracted from Paris polyphylla, was reported to have anti-tumor activity. However, the detailed mechanism for this activity remains unclear. Here, we investigated the inhibitory effects of PPI on glioma cells and its mechanisms in vitro. U251 cells were treated with various concentrations of PPI (2-9 μM) for 24 to 72 h. The inhibition of U251 cell proliferation by PPI was assessed by MTT assay. The effects on cell cycle and apoptosis were examined by flow cytometry with PI and annexin V-FITC/PI dual staining, and the cell mitochondrial membrane potential level was evaluated by fluorescence microscopy with JC-1 staining. The expression levels of apoptosis-related proteins and JNK signal pathway proteins were evaluated by western blot analysis. Results showed that PPI significantly inhibited the proliferation of U251 cells in a concentration-dependent manner. PPI induced G2/M phase arrest and apoptosis, and it upregulated the expressions of Bax, cytochrome c, and p-JNK, but downregulated the expression of the anti-apoptotic protein Bcl-2 in U251 cells. Moreover, PPI provoked the depolarization of the mitochondrial membrane potential. In addition, apoptosis induced by the PPI was remarkably suppressed by the JNK inhibitor SP600125. Our data provide evidence that PPI inhibits proliferation and induces apoptotic cell death in U251 cells. This effect may be associated with the JNK pathway. These results suggest that PPI is an activator of the JNK signaling pathway with a potential anti-glioma effect.

Paris Saponin I Sensitizes Gastric Cancer Cell Lines to Cisplatin via Cell Cycle Arrest and Apoptosis

BACKGROUND Dose-related toxicity is the major restriction of cisplatin and cisplatin-combination chemotherapy, and is a challenge for advanced gastric cancer treatment. We explored the possibility of using Paris saponin I as an agent to sensitize gastric cancer cells to cisplatin, and examined the underlying mechanism. MATERIAL AND METHODS Growth inhibition was detected by MTT assay. The cell cycle and apoptosis were detected using flow cytometry and Annexin V/PI staining. The P21waf1/cip1, Bcl-2, Bax, and caspase-3 protein expression were detected using Western blot analysis. RESULTS The results revealed that PSI sensitized gastric cancer cells to cisplatin, with low toxicity. The IC50 value of cisplatin in SGC-7901 cell lines was decreased when combined with PSI. PSI promoted cisplatin-induced G2/M phase arrest and apoptosis in a cisplatin concentration-dependent manner. Bcl-2 protein expression decreased, but Bax, caspase-3, and P21waf1/cip1 protein expression increased with PSI treatment. CONCLUSIONS The underlying mechanism of Paris saponin I may be related to targeting the apoptosis pathway and cell cycle blocking, which suggests that PSI is a potential therapeutic sensitizer for cisplatin in treating gastric cancer.

Aqueous Extract of Paris polyphylla (AEPP) Inhibits Ovarian Cancer via Suppression of Peroxisome Proliferator-Activated Receptor-Gamma Coactivator (PGC)-1alpha

Chemotherapy, a major approach was used in carcinoma treatment, always involves the development of drug resistance as well as side-effects that affect the quality of patients’ lives. An association between epithelial-mesenchymal transition (EMT) and chemotherapy resistance was established recently. We demonstrate in this paper that the aqueous extract of Paris polyphylla (AEPP)—a traditional Chinese medicine—can be used in various cancer types for suppression of carcinogenesis. We evaluated the suppressions of EMT and mitochondrial activity by AEPP treatment in a high-glucose (HG) induced-human ovarian carcinoma cell line (OVCAR-3 cells). The mitochondrial morphology was investigated using MitoTracker Deep Red FM staining. Our results indicated that AEPP reduced the viability of OVCAR-3 cells considerably through induction of apoptosis. However, this inhibitory potential of AEPP was attenuated by HG induction in OVCAR-3 cells. The levels of estrogen-related receptor (ERR)-alpha activator and peroxisome proliferator-activated receptor-gamma coactivator (PGC)-1alpha were elevated by HG induction, but were suppressed by AEPP treatment. Down-regulations of cell survival and EMT were oberved in OVCAR-3 cells through suppression of PGC-1alpha by AEPP treatment. These results were confirmed through PGC-1alpha knockdown and overexpression in OVCAR-3 cells. Thus, AEPP can be beneficial for treating ovarian cancer and has potential for development of an integrative cancer therapy against ovarian cancer proliferation, metastasis, and migration.

Bacopaside I ameliorates cognitive impairment in APP/PS1 mice via immune-mediated clearance of β-amyloid

Standardized extracts of Bacopa monniera (BME) have been shown to exert a neuroprotective effect against mental diseases, such as depression, anxiety and Alzheimer's disease (AD), in chronic administration studies. However, its mechanism of action has remained unclear. In this study, we evaluated the therapeutic effect of Bacopaside I (BS-I), a major triterpenoid saponin of BME, on the cognitive impairment and neuropathology in APP/PS1 transgenic mice and explored the possible mechanism from a biological systems perspective. We found that BS-I treatment significantly ameliorated learning deficits, improved long-term spatial memory, and reduced plaque load in APP/PS1 mice. We constructed BS-I's therapeutic effect network by mapping the nodes onto the protein-protein interaction (PPI) network constructed according to their functional categories based on genomic and proteomic data. Because many of the top enrichment categories related to the processes of the immune system and phagocytosis were detected, we proposed that BS-I promotes amyloid clearance via the induction of a suitable degree of innate immune stimulation and phagocytosis. Our research may help to clarify the neuroprotective effect of BME and indicated that natural saponins target the immune system, which may offer new research avenues to discover novel treatments for AD.

Polyphyllin VII induces apoptosis in HepG2 cells through ROS-mediated mitochondrial dysfunction and MAPK pathways

Background

Paris polyphylla is an oriental folk medicine that has anticancer activities both in vivo and in vitro. Polyphyllin VII (PP7), a pennogenyl saponin from P. polyphylla has been found to exert strong anticancer activity. However, the underlying mechanisms are poorly understood. In the present study, the anticancer effect of polyphyllin VII against human liver cancer cells and the molecular mechanisms were investigated.

Methods

Cellular viability was measured by MTT assay. Apoptosis, intracellular reactive oxygen species (ROS) and mitochondrial membrane potential levels were evaluated using the InCell 2000 confocal microscope. The expression levels of apoptotic-related proteins were evaluated by Western blotting.

Results

PP7 strongly inhibited the cell growth and induced apoptosis and necrosis in hepatocellular carcinoma HepG2 cells. Meanwhile, PP7 up-regulated the levels of Bax/Bcl-2, cytochrome c, the cleaved forms of caspases-3, -8, -9, and poly (ADP-ribose) polymerase in a dose- and time-dependent manner, indicating that PP7 induced apoptosis in HepG2 cells through both intrinsic and extrinsic pathways. Moreover, PP7 provoked the production of intracellular ROS and the depolarization of mitochondrial membrane potential. Further analysis showed that PP7 significantly augmented the phosphorylation of JNK, ERK and p38, the major components of mitogen-activated protein kinase (MAPK) pathways, and the expressions of tumor suppressor proteins p53 and PTEN. In addition, PP7-induced apoptosis was remarkably attenuated by MAPK inhibitors and ROS inhibitor.

Conclusions

These results demonstrated that PP7 induced apoptotic cell death in HepG2 cells through both intrinsic and extrinsic pathways by promoting the generation of mitochondrial-mediated ROS and activating MAPK and PTEN/p53 pathways.

Electronic supplementary material

The online version of this article (doi:10.1186/s12906-016-1036-x) contains supplementary material, which is available to authorized users.

In vitro cytotoxic screening of 31 crude extracts of Thai herbs on a chondrosarcoma cell line and primary chondrocytes and apoptotic effects of selected extracts

Thirty-one dichloromethane and methanol crude extracts of 16 herb species used in Thai traditional folk medicine were studied for their cytotoxic activities on the SW 1353 chondrosarcoma cell line and primary chondrocytes. Methyl thiazolyl tetrazolium (MTT) cell viability assay and flow cytometric method were used as screening tools for cytotoxicity testing. The half maximal inhibitory concentration (IC50) was measured and reported for each crude extract. Apoptosis, necrosis, and cell viability were measured by flow cytometry at IC50. Two out of 31 herbal extracts, methanol extracts of Paris polyphylla var. chinensis and Ficus thailandica C.C. Berg & S. Gardner, showed potent anticancer activity. They demonstrated high apoptosis induction activity in SW 1353 cells but had less effect on percentage of viability and necrosis of normal chondrocyte cells. Cytotoxic screening and apoptosis assays suggest the potential anticancer activity of some plants used in Thai traditional medicine and provide information concerning their direct effects.

Curcumin inhibits advanced glycation end product-induced oxidative stress and inflammatory responses in endothelial cell damage via trapping methylglyoxal

Methylglyoxal (MGO)-induced carbonyl stress and pro-inflammatory responses have been suggested to contribute to endothelial dysfunction. Curcumin (Cur), a polyphenolic compound from Curcuma longa L., may protect endothelial cells against carbonyl stress-induced damage by trapping dicarbonyl compounds such as MGO. However, Cur-MGO adducts have not been studied in depth to date and it remains to be known whether Cur-MGO adducts are able to attenuate endothelial damage by trapping MGO. In the present study, 1,2-diaminobenzene was reacted with MGO to ensure the reliability of the reaction system. Cur was demonstrated to trap MGO at a 1:1 ratio to form adducts 1, 2 and 3 within 720 min. The structures of these adducts were identified by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry. The kinetic curves of Cur (10(-7), 10(-6) and 10(-5) M) were measured from 0-168 h by fluorescent intensity. Cur significantly inhibited the formation of advanced glycation end products (AGEs). The differences in oxidative damage and the levels of pro-inflammatory cytokines following MGO + HSA or Cur-MGO treatment were investigated in human umbilical vein endothelial cells (HUVECs). Exposure of HUVECs to the Cur-MGO reaction adducts significantly reduced the intracellular ROS levels and improved cell viability compared with MGO alone. Furthermore, there was a significant reduction in the expression levels of transforming growth factor-β1 and intercellular adhesion molecule(-1) following treatment with Cur-MGO adducts compared with MGO alone. These results provide further evidence that the trapping of MGO by Cur inhibits the formation of AGEs. The current study indicates that the protective effect of Cur on carbonyl stress and pro-inflammatory responses in endothelial damage occurs via the trapping of MGO.

Steroidal saponins from Paris polyphylla induce apoptotic cell death and autophagy in A549 human lung cancer cells

BACKGROUND

Paris polyphylla (Chinese name: Chonglou) had been traditionally used for a long time and shown anti-cancer action. Based on the previous study that paris polyphylla steroidal saponins (PPSS) induced cytotoxic effect in human lung cancer A549 cells, this study was designed to further illustrate the mechanisms underlying.

MATERIALS AND METHODS

The mechanisms involved in PPSS-induced A549 cell death were investigated by phase contrast microscopy and fluorescence microscopy, flow cytometry and western blot analysis, respectively.

RESULTS

PPSS decreased the proportion of viable A549 cells, and exposure of A549 cells to PPSS led to both apoptosis and autophagy. Apoptosis was due to activations of caspase-8, caspase-3, as well as cleavage of PARP, and autophagy was confirmed by up-regulation of Beclin 1 and the conversion from LC3 I to LC3 II.

CONCLUSIONS

PPSS was able to induce lung cancer A549 cell apoptosis and autophagy in vitro, the results underlining the possibility that PPSS would be a potential candidate for intervention against lung cancer.

Steroidal saponins from Paris polyphylla suppress adhesion, migration and invasion of human lung cancer A549 cells via down-regulating MMP-2 and MMP-9

BACKGROUND

Tumor metastases are the main reasons for oncotherapy failure. Paris polyphylla (Chinese name: Chonglou) has traditionally been used for its anti-cancer actions. In this article, we focus on the regulation of human lung cancer A549 cell metastases and invasion by Paris polyphylla steroidal saponins (PPSS).

MATERIALS AND METHODS

Cell viability was evaluated in A549 cells by MTT assay. Effects of PPSS on invasion and migration were investigated by wound-healing and matrigel invasion chamber assays. Adhesion to type IV collagen and laminin was evaluated by MTT assay. Expression and protease activity of two matrix metalloproteinases (MMPs), MMP-2 and MMP-9, were analyzed by Western blotting and gelatin zymography, respectively.

RESULTS

PPSS exerted growth inhibitory effects on A549 cells, and effectively inhibited A549 cell adhesion, migration and invasion in a concentration-dependent manner. Western blotting and gelatin zymography analysis revealed that PPSS inhibited the expression and secretion of MMP-2 and MMP-9 in A549 cells.

CONCLUSIONS

PPSS has the potential to suppress the migration, adhesion and invasion of A549 cells. PPSS could be a potential candidate for interventions against lung cancer metastases.

Pennogenyl Saponins from Paris quadrifolia L. Induce Extrinsic and Intrinsic Pathway of Apoptosis in Human Cervical Cancer HeLa Cells

Pennogenyl saponins are the active compounds of large number of plant species and consequently many polyherbal formulations. Hence, great interest has been shown in their characterization and in the investigation of their pharmacological and biological properties, especially anticancer. This present study reports on the evaluation of cytotoxic effects and explanation of the molecular mechanisms of action of the two pennogenyl saponins (PS 1 and PS 2) isolated from Paris quadrifolia L. rhizomes on human cervical adenocarcinoma cell line HeLa. To determine the viability of the cells treated with the compounds we used real-time cell proliferation analysis and found that the pennogenyl saponins PS 1 and PS 2 strongly inhibited the tumor cells growth with IC50 values of 1.11 ± 0.04 μg/ml and 0.87 ± 0.05 μg/ml, respectively. The flow cytometry analysis indicated that the two compounds induced apoptosis in a dose-dependent manner and decreased mitochondrial membrane potential in HeLa cells in the early stage of apoptosis. Quantitative PCR and Western Blot analysis showed that the two saponins significantly increased mRNA expression of FADD and BID as well as induced caspase-8 via increased of procaspase-8 processing in the treated cells. The results of this study suggest that both the extrinsic death receptor and intrinsic mitochondrial pathways are involved in the programmed cell death.

Inhibition of Tumor Growth and Immunomodulatory Effects of Flavonoids and Scutebarbatines of Scutellaria barbata D. Don in Lewis-Bearing C57BL/6 Mice

Immunomodulatory effect has been found to be an important therapeutic measure for immune responses against cancer. In this study, we evaluated the inhibition of Scutellaria barbata D. Don (SB), an anti-inflammatory and an antitumor Chinese herb, including flavonoids and scutebarbatines on tumor growth and its immunomodulatory effects in vivo. HPLC and LC/MS/MS methods were conducted for the analysis of flavonoids and scutebarbatines in SB. Lewis-bearing C57BL/6 mice model was established and tumor volume was evaluated by high frequency color ultrasound experiment. ELISA and western blot analysis were performed for the determination of immunomodulatory factors. SB treatment at the dose of 10, 6.67, and 3.33 g crude drug/kg/d significantly inhibited tumor growth of Lewis-bearing C57BL/6 mice with the inhibition rates of 44.41 ± 5.44%, 33.56 ± 4.85%, and 27.57 ± 4.96%, respectively. More importantly, the spleen and thymus indexes were increased remarkably by SB treatment. SB could decrease IL-17, IL-10, FOXP3, TGF-β1, RORγt, and IL-6 levels whereas it could increase remarkably IL-2 and IFN-γ levels. Our results demonstrated that SB could inhibit tumor growth in vivo through regulating immune function in tumor-bearing mice and suggested that the immunomodulatory function of SB had a potential therapeutic effect in lung cancer.

Cytotoxic saponin poliusaposide from Teucrium polium

Three saponin glycosides have been isolated and characterized from Teucrium polium L. (Lamiaceae).

RGD-peptides modifying dexamethasone: to enhance the anti-inflammatory efficacy and limit the risk of osteoporosis

RGD-peptides modifying dexamethasone can enhance the anti-inflammatory efficacy and limit the risk of osteoporosis.

The protective effect of Smilax glabra extract on advanced glycation end products-induced endothelial dysfunction in HUVECs via RAGE-ERK1/2-NF-κB pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Smilax glabra Roxb. (SGR) is a traditional Chinese herb that has been used in folk for the treatment of diabetic vascular complications. Advanced glycation end products (AGEs)-induced endothelial dysfunction has been thought to be a major cause of diabetic vascular complications. The present study was conducted to investigate the protective effect of SGR extract on AGEs-induced endothelial dysfunction and its underlying mechanisms.

MATERIALS AND METHODS

Human umbilical vein endothelial cells (HUVECs) were exposed to 200 μg/ml AGEs to induce endothelial dysfunction. Acridine orange/ethidium bromide (AO/EB) fluorescence assay and Annexin-V/PI double-staining were performed to determine endothelium apoptosis. Dihydroethidium (DHE) fluorescence probe, SOD and MDA kits were used to evaluate oxidative stress. The effect of SGR extract on AGEs-induced TGF-beta1 expression was determined by immunocytochemistry and western blotting. Attenuations of SGR extract on receptor for AGEs (RAGE) expression, extracellular regulated protein kinases (ERK1/2) activation and NF-κB phosphorylation were determined by immunofluorescence assay and western blotting. The blockade assays for RAGE and ERK1/2 were carried out using a specific RAGE-antibody (RAGE-Ab) or a selective ERK1/2 inhibitor PD98059 in immunofluorescence assay.

RESULTS

The pretreatment of SGR extract (0.125, 0.25 and 0.5 mg crude drug/ml) significantly attenuated AGEs-induced endothelium apoptosis, and down-regulated TGF-beta1 protein expression in HUVECs. It was also well shown that SGR extract could down-regulate dose-dependently ROS over-generation, MDA content, TGF-beta1 expression, ERK1/2 and NF-κB activation whereas increase significantly SOD activity. Furthermore, the AGEs-induced ERK1/2 activation could be attenuated by the blockade of RAGE-Ab (5 μg/ml) while the NF-κB activation was ameliorated by ERK1/2 inhibitor PD98059 (10 μM).

CONCLUSION

These results indicated that SGR extract could attenuate AGEs-induced endothelial dysfunction via RAGE-ERK1/2-NF-κB pathways. Our findings suggest that SGR extract may be beneficial for attenuating endothelial dysfunction in diabetic vascular complications.