The saponin monomer of dwarf lilyturf tuber, DT-13, inhibits angiogenesis under hypoxia and normoxia via multi-targeting activity

Alterations in factors associated with diabetic retinopathy combined with thrombosis: A review

Diabetic retinopathy (DR) is one of the most common and serious microvascular complications of diabetes mellitus, the incidence of which has been increasing annually, and it is the main cause of vision loss in diabetic patients and a common cause of blindness. It is now found that thrombosis plays a crucial role in the disease progression in DR patients, and the final vision loss in DR may be related to the occurrence of thrombosis in the retinal vessels, which is dominated by abnormal endothelial cell function, together with platelet dysfunction, imbalance of coagulation and fibrinolytic function, and related alterations of inflammatory factors leading to the main cause of thrombotic disease in DR patients. In this review, we examine the role between DR and thrombosis and the association of each factor, including endothelial dysfunction; platelet dysfunction; coagulation-fibrinolytic imbalance; and alterations in inflammatory factors.

Inhibiting Angiogenesis by Anti-Cancer Saponins: From Phytochemistry to Cellular Signaling Pathways

Saponins are one of the broadest classes of high-molecular-weight natural compounds, consisting mainly of a non-polar moiety with 27 to 30 carbons and a polar moiety containing sugars attached to the sapogenin structure. Saponins are found in more than 100 plant families as well as found in marine organisms. Saponins have several therapeutic effects, including their administration in the treatment of various cancers. These compounds also reveal noteworthy anti-angiogenesis effects as one of the critical strategies for inhibiting cancer growth and metastasis. In this study, a comprehensive review is performed on electronic databases, including PubMed, Scopus, ScienceDirect, and ProQuest. Accordingly, the structural characteristics of triterpenoid/steroid saponins and their anti-cancer effects were highlighted, focusing on their anti-angiogenic effects and related mechanisms. Consequently, the anti-angiogenic effects of saponins, inhibiting the expression of genes related to vascular endothelial growth factor (VEGF) and hypoxia-inducible factor 1-α (HIF-1α) are two main anti-angiogenic mechanisms of triterpenoid and steroidal saponins. The inhibition of inflammatory signaling pathways that stimulate angiogenesis, such as pro-inflammatory cytokines, mitogen-activated protein kinase (MAPKs), and phosphoinositide 3-kinases/protein kinase B (PI3K/Akt), are other anti-angiogenic mechanisms of saponins. Furthermore, the anti-angiogenic and anti-cancer activity of saponins was closely related to the binding site of the sugar moiety, the type and number of their monosaccharide units, as well as the presence of some functional groups in their aglycone structure. Therefore, saponins are suitable candidates for cancer treatment by inhibiting angiogenesis, for which extensive pre-clinical and comprehensive clinical trial studies are recommended.

Natural Products: A Promising Therapeutics for Targeting Tumor Angiogenesis

Tumor-associated angiogenesis is a key target for anti-cancer therapy. The imbalance between pro-angiogenic and anti-angiogenic signals elicited by tumor cells or tumor microenvironment always results in activating "angiogenic switch". Tumor angiogenesis functions in multi-aspects of tumor biology, including endothelial cell apoptosis, tumor metastasis, and cancer stem cell proliferation. Numerous studies have indicated the important roles of inexpensive and less toxic natural products in targeting tumor angiogenesis-associated cytokines and apoptotic signaling pathways. Our current knowledge of tumor angiogenesis is based mainly on experiments performed on cells and animals, so we summarized the well-established models for angiogenesis both in vitro and in vivo. In this review, we classified and summarized the anti-angiogenic natural agents (Polyphenols, Polysaccharides, Alkaloids, Terpenoids, Saponins) in targeting various tumor types according to their chemical structures at present, and discussed the mechanistic principles of these natural products on regulating angiogenesis-associated cytokines and apoptotic signaling pathways. This review is to help understanding the recent progress of natural product research for drug development on anti-tumor angiogenesis.

HIF-1α is a Potential Molecular Target for Herbal Medicine to Treat Diseases

HIF-1α is an important factor regulating oxygen balance in mammals, and its expression is closely related to various physiological and pathological conditions of the body. Because HIF-1α plays an important role in the occurrence and development of cancer and other diseases, it has become an enduring research hotspot. At the same time, natural medicines and traditional Chinese medicine compounds have amazing curative effects in various diseases related to HIF-1 subtype due to their unique pharmacological effects and more effective ingredients. Therefore, in this article, we first outline the structure of HIF-1α and the regulation related to its expression, then introduce various diseases closely related to HIF-1α, and finally focus on the regulation of natural medicines and compound Chinese medicines through various pathways. This will help us understand HIF-1α systematically, and use HIF-1α as a target to discover more natural medicines and traditional Chinese medicines that can treat related diseases.

Statins induce skeletal muscle atrophy via GGPP depletion-dependent myostatin overexpression in skeletal muscle and brown adipose tissue

Myopathy is the major adverse effect of statins. However, the underlying mechanism of statin-induced skeletal muscle atrophy, one of statin-induced myopathy, remains to be elucidated. Myostatin is a negative regulator of skeletal muscle mass and functions. Whether myostatin is involved in statin-induced skeletal muscle atrophy remains unknown. In this study, we uncovered that simvastatin administration increased serum myostatin levels in mice. Inhibition of myostatin with follistatin, an antagonist of myostatin, improved simvastatin-induced skeletal muscle atrophy. Simvastatin induced myostatin expression not only in skeletal muscle but also in brown adipose tissue (BAT). Mechanistically, simvastatin inhibited the phosphorylation of forkhead box protein O1 (FOXO1) in C2C12 myotubes, promoting the nuclear translocation of FOXO1 and thereby stimulating the transcription of myostatin. In differentiated brown adipocytes, simvastatin promoted myostatin expression mainly by inhibiting the expression of interferon regulatory factor 4 (IRF4). Moreover, the stimulative effect of simvastatin on myostatin expression was blunted by geranylgeranyl diphosphate (GGPP) supplementation in both myotubes and brown adipocytes, suggesting that GGPP depletion was attributed to simvastatin-induced myostatin expression. Besides, the capacities of statins on stimulating myostatin expression were positively correlated with the lipophilicity of statins. Our findings provide new insights into statin-induced skeletal muscle atrophy. Graphical headlights 1. Simvastatin induces skeletal muscle atrophy via increasing serum myostatin levels in mice; 2. Simvastatin promotes myostatin expression in both skeletal muscle and brown adipose tissue through inhibiting GGPP production; 3. The stimulating effect of statins on myostatin expression is positively correlated with the lipophilicity of statins.

Targeting hypoxia-inducible factor-1, for cancer treatment: Recent advances in developing small-molecule inhibitors from natural compounds

Rapid progress in molecular cancer biology coupled with the discovery of novel oncology drugs has opened new horizons for cancer target discovery. As one of the crucial signaling pathways related to tumorigenesis, hypoxia-inducible factor-1 (HIF-1) coordinates the activity of many transcription factors and their downstream molecules that impact tumor growth and metastasis. Accumulating evidence suggests that the transcriptional responses to acute hypoxia are mainly attributable to HIF-1α. Moreover, the overexpression of HIF-1α in several solid cancers has been found to be strongly associated with poor prognosis. Thus, pharmacological targeting of the HIF-1 signaling pathways has been considered as a new strategy for cancer therapy in the recent years. Although over the past decade, tremendous efforts have been made in preclinical studies to develop new HIF-1 inhibitors from natural products (reservoirs of novel therapeutic agents), to date, these efforts have not been successfully translated into clinically available treatments. In this review, we provide new insights into the bio-pharmacological considerations for selecting natural compounds as potential HIF-1 inhibitors to accelerate anti-cancer drug development. In addition, we highlighted the importance of assessing the dependency of cancer on HIF1A to shortlist cancer types as suitable disease models. This may subsequently lead to new paradigms for discovering more HIF-1 inhibitors derived from natural products and facilitate the development of potent therapeutic agents targeting specific cancer types.

Synergistic combination of DT-13 and Topotecan inhibits aerobic glycolysis in human gastric carcinoma BGC-823 cells via NM IIA/EGFR/HK II axis

DT-13 combined with topotecan (TPT) showed stronger antitumour effects in mice subcutaneous xenograft model compared with their individual effects in our previous research. Here, we further observed the synergistically effect in mice orthotopic xenograft model. Metabolomics analysis showed DT-13 combined with TPT alleviated metabolic disorders induced by tumour and synergistically inhibited the activity of the aerobic glycolysis-related enzymes in vivo and in vitro. Mechanistic studies revealed that the combination treatment promoted epidermal growth factor receptor (EGFR) degradation through non-muscle myosin IIA (NM IIA)-induced endocytosis of EGFR, further inhibited the activity of hexokinase II (HK II), and eventually promoted the aerobic glycolysis inhibition activity more efficiently compared with TPT or DT-13 monotherapy. The combination therapy also inhibited the specific binding of HK II to mitochondria. When using the NM II inhibitor (-)002Dblebbistatin or MYH-9 shRNA, the synergistic inhibition effect of DT-13 and TPT on aerobic glycolysis was eliminated in BGC-823 cells. Immunohistochemical analysis revealed selective up-regulation of NM IIA while specific down-regulation of p-CREB, EGFR, and HK II by the combination therapy. Collectively, these findings suggested that this regimen has significant clinical implications, warranted further investigation.

DT-13 suppresses breast cancer metastasis by modulating PLOD2 in the adipocytes microenvironment

BACKGROUND

Metastasis is the main cause of death in breast cancer and previous researches have indicated the pivotal role of adipocytes in breast cancer metastasis. DT-13, the saponin monomer 13 of the Dwarf lilyturf tuber, has been proved to exert potential anti-metastatic effect, the detailed mechanisms have not been well elucidated and the role of DT-13 in modulating adipocyte-breast cancer microenvironment has been given little attention.

PURPOSE

This study aims to explore the mechanisms of DT-13 in inhibiting breast cancer metastasis and whether DT-13 inhibit breast cancer metastasis via modulating the interactions between adipocytes and breast cancer cells.

METHODS

The cytotoxic effect of DT-13 on breast cancer cell viability was detected by MTT assay. Migration assays was used to conduct the effect of DT-13 on breast cancer cells migration. Orthotopic xenograft tumor model was used to test the effect of DT-13 on breast cancer metastasis. qRT-PCR and Western blot were used to investigate the mechanisms of DT-13 inhibiting breast cancer metastasis.

RESULTS

DT-13 inhibited breast cancer cells migration at the concentration without cytotoxicity. Furthermore, DT-13 decreased PLOD2 expression through modulating JAK/STAT3 and PI3K/AKT signaling pathways directly or indirectly in the adipocyte-breast cancer microenvironment. Orthotopic implantation mouse model of breast cancer further confirmed that DT-13 inhibited breast cancer metastasis via downregulating PLOD2 in vivo.

CONCLUSION

DT-13 suppressed breast cancer metastasis via reducing the expression of PLOD2.

Topotecan induces apoptosis via ASCT2 mediated oxidative stress in gastric cancer

BACKGROUND

Topotecan (TPT) is a Topo I inhibitor and shows obvious anti-cancer effects on gastric cancer. Cancer cells reprogram their metabolic pathways to increase nutrients uptake, which has already been a hallmark of cancer. But the effect of TPT on metabolism in gastric cancer remains unknown.

PURPOSE

To investigate the effect of TPT on metabolism in gastric cancer.

METHODS

ATP production was measured by ATP Assay kit. Glucose and glutamine uptake were measured by Glucose (HK) Assay Kit and Glutamine/Glutamate Determination Kit respectively. To detect glutathione (GSH) concentration and reactive oxygen species (ROS) generation, GSH and GSSG Assay Kit and ROS Assay Kit were adopted. Apoptosis rates, mitochondrial membrane potential (MMP) were determined by flow cytometry and protein levels were analyzed by immumohistochemical staining and western blotting.

RESULTS

TPT increased ATP production. TPT promoted glucose uptake possibly via up-regulation of hexokinase 2 (HK2) or glucose transporter 1 (GLUT1) expression, while decreased glutamine uptake by down-regulation of ASCT2 expression. ASCT2 inhibitor GPNA and ASCT2 knockdown significantly suppressed the growth of gastric cancer cells. Inhibition of ASCT2 reduced glutamine uptake which led to decreased production of GSH and increased ROS level. ASCT2 knockdown induced apoptosis via the mitochondrial pathway and weakened anti-cancer effect of TPT.

CONCLUSION

TPT inhibits glutamine uptake via down-regulation of ASCT2 which causes oxidative stress and induces apoptosis through the mitochondrial pathway. Moreover, TPT inhibits proliferation partially via ASCT2. These observations reveal a previously undescribed mechanism of ASCT2 regulated gastric cancer proliferation and demonstrate ASCT2 is a potential anti-cancer target of TPT.

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.

DT-13 Inhibits Proliferation and Metastasis of Human Prostate Cancer Cells Through Blocking PI3K/Akt Pathway

DT-13, a saponin monomer 13 from the dwarf lilyturf tuber, was reported to exhibit anti-inflammatory, hepatoprotective, cardioprotective as well as antitumor activities in a number of tumor cells. Prostate cancer is the second leading cause of cancer death in males, discovery of novel antitumor drug for therapy of prostate cancer is expected. Aiming to evaluate whether DT-13 could become a candidate to treat prostate cancer, we recently investigated the antitumor effect of DT-13 on human prostate cancer cells and the underlying mechanism. DT-13 was found to effectively inhibit proliferation and metastasis of prostate cancer PC3 and DU145 cell lines in a dose-dependent manner. Treatment by DT-13 resulted in a mitochondria-mediated apoptosis, which was accompanied by the chromatin condensation and nuclear shrinkage in the prostate cancer cells. Moreover, DT-13 caused remarkable upregulation of Bax, Bad, Cytochrome C, cleaved -caspase 3, -caspase 9 and -PARP, in contrast to the downregulation of Bcl-2. Nevertheless, no obvious change in intracellular ROS level was observed after DT-13 treatment. We further demonstrated that DT-13 could inhibit PC3 cell metastasis in which suppression of Integrinβ1 and MMP2/9 might be involved. Western blot analysis indicated DT-13 significantly decreased the phosphorylation of PDK1, Akt, mTOR as well as p70S6K, suggesting the pro-apoptotic and anti-metastatic effects of DT-13 on prostate cancer cells might be attributed to the blockade of PI3K/Akt pathway. Collectively, our findings suggest DT-13 is worthy of further investigation as a drug candidate for the treatment of prostate cancer.

Synergistic combination of DT-13 and topotecan inhibits human gastric cancer via myosin IIA-induced endocytosis of EGF receptor in vitro and in vivo

Combination therapy has a higher success rate for many cancers compared to mono-therapy. The treatment of Topotecan (TPT) on gastric cancer (GC) is limited by its toxicity and the potential drug resistance. We found that the combination of the saponin monomer 13 from the dwarf lilyturf tuber (DT-13), performing anti-metastasis and anti-angiogenesis effects, with TPT synergistically induced apoptotic cytotoxicity in GCs with high EGF receptor (EGFR) expression, which was dependent on DT-13-induced endocytosis of EGFR. With TPT, DT-13 promoted EGFR ubiquitin--mediated degradation through myosin IIA-induced and Src/ caveolin-1 (Cav-1)-induced endocytosis of EGFR; inhibited EGFR downstream signalling and then increased the pro-apoptotic effects. Moreover, the synergistic pro-apoptotic efficacy of DT-13 and TPT in GCs with high EGFR expression was eliminated by both the NM II inhibitor (−)-blebbistatin and MYH-9 shRNA. The combination therapy of DT-13 with TPT showed stronger anti-tumour effects in vivo compared with their individual effects. Moreover, the results of combination therapy revealed selective upregulation of pro-apoptotic activity in TUNEL assays and cleaved caspase-3 and NM IIA in immunohischemical analysis; while specific downregulation of p-extracellular regulated kinase 1/2 (p-ERK1/2), EGFR and Cav-1 in immunohischemical analysis. Collectively, these findings have significant clinical implications for patients with tumours harbouring high EGFR expression due to the possible high sensitivity of this regimen.

DT-13 synergistically potentiates the sensitivity of gastric cancer cells to topotecan via cell cycle arrest in vitro and in vivo

Natural medicine has multi-levels, multi-paths and multi-targets, and an increasing number of reports have confirmed that the combination of natural medicine with chemotherapy drugs exhibit a significant synergistic effect. It is necessary to find drug combination strategies to enhance efficacy and reduce toxicity, which can relieve the restrictions on the use of several chemotherapy drugs that have serious toxicity. Our previous reports showed that DT-13 inhibits cancer proliferation, invasion, migration, metastasis, and angiogenesis and induces autophagy. In this study, we evaluated the anti-proliferation effect of DT-13 on a panel of 40 different cancer cell lines for the first time. Moreover, it is also the first time that the combination of DT-13 with 5 different chemotherapy drugs on 3 common cancer cells has been examined. We further confirmed that DT-13 enhanced the sensitivity of gastric cancer cells to topotecan (TPT) via cell cycle arrest in vitro and in vivo. Considering that TPT has been subjected to restriction because of its serious toxicity, DT-13 showed the ability to enhance its effect and reduce its toxicity, which could provide a strategy to reduce the toxic and clinical side effects of TPT.

DT-13 synergistically enhanced vinorelbine-mediated mitotic arrest through inhibition of FOXM1-BICD2 axis in non-small-cell lung cancer cells

Non-small-cell lung cancer (NSCLC) is the most commonly diagnosed malignant disease with the leading cause of cancer-related death. Combination treatment remains the major strategy in the clinical therapy of NSCLC. Vinorelbine (NVB), a semi-synthetic vinca alkaloid, is used for advanced and metastatic NSCLC by destabilizing microtubule formation to induce mitotic arrest and cell death. However, the side effect of NVB heavily affected its effectiveness in clinical therapy. Hence, it is of great significance to develop new agents to synergize with NVB and decrease the adverse effect. In our study, we found that the saponin monomer 13 of the dwarf lilyturf tuber, DT-13, exhibiting anti-angiogenesis and anti-metastasis effect, synergized with NVB to inhibit cell proliferation in NSCLC cells. The synergistic interaction of DT-13 and NVB was confirmed by combination Index values. Also, DT-13 and NVB act in concert to inhibit the long-term colony formation. Furthermore, DT-13/NVB co-treatment cooperated to induce mitotic arrest and subsequent apoptosis. Mechanistically, we found that nuclear expression of transcription factors forkhead box M1 (FOXM1) and levels of motor adaptor bicaudal D2 (BICD2) were dramatically reduced by combination treatment. Importantly, oncogene FOXM1 was identified as the crucial regulator of BICD2, which played critical roles in NVB-induced mitotic spindle defects. Moreover, overexpression of FOXM1 and BICD2 significantly reversed mitotic arrest induced by DT-13/NVB co-treatment, and siRNAs against both genes greatly increased the combinational effects. In addition, in vivo study revealed that DT-13 combined with NVB significantly suppressed tumor growth in nude mice xenograft model, and downregulated the expression of FOXM1 and BICD2 in tumor tissues, which was consistent with in vitro study. In conclusion, DT-13 might provide a novel strategy for the chemosensitization of NVB in NSCLC therapy.

Ophiopogon japonicus--A phytochemical, ethnomedicinal and pharmacological review

ETHNOPHARMACOLOGICAL RELEVANCE

Ophiopogonis Radix (Maidong in Chinese), the root of Ophiopogon japonicus, is widely used in local medicines of China, Japan and some south-eastern Asian countries. According to the traditional Chinese medicine (TCM) principle, Ophiopogonis Radix nourishes the yin, promotes body fluid production, moistens the lung, eases the mind and clears away heart fire. This review summarizes the achievements of the investigations in botany, phytochemistry, quality control, traditional uses, pharmacological activities and clinical studies on O. japonicus; this review also describes the shortcomings of studies on this herbal drug and thus serves as the basis of further scientific research and development of this traditional herbal drug.

MATERIALS AND METHODS

O. japonicus-related information was collected from various resources, including books on Chinese herbs and the Internet databases, such as Google Scholar, SciFinder, Web of Science, Elsevier, ACS, PubMed and China Knowledge Resource Integrated (CNKI).

RESULTS

O. japonicus is widely distributed in East Asia, especially in China. Numerous compounds were identified from this plant. The main components of O. japonicus include steroidal saponins, homoisoflavonoids and polysaccharides, which exhibited various pharmacological activities, such as cardiovascular protection, anti-inflammation, anticancer, anti-oxidation, immunomodulation, cough relief, antimicrobial, and anti-diabetes.

CONCLUSIONS

O. japonicus is a common traditional Chinese herbal drug used as the main ingredient in many prescriptions. Modern researches verified that O. japonicus can be used either as a healthy food or a therapeutic agent for disease prevention and treatment. The molecular mechanisms and chemical principles of this herbal medicine should be further explored.

CXCL16 induces angiogenesis in autocrine signaling pathway involving hypoxia-inducible factor 1α in human umbilical vein endothelial cells

Chemokine (C-X-C motif) ligand 16 (CXCL16) is a new angiogenic factor inducing angiogenesis via extracellular signal-regulated kinases pathway. To further understand the molecular mechanism underlying CXCL16‑induced angiogenesis, we explored involvement of other relevant pathways in CXCL16-induced angiogenesis. In the present study, we investigated the mechanisms underlying CXCL16-induced angiogenesis in human umbilical vein endothelial cells (HUVECs). CXCL16 promoted HUVEC proliferation, tube formation and migration. Enzyme-linked immunosorbent assay revealed that CXCL16 induced vascular endothelial growth factor secretion from HUVECs. Western blot analysis showed that CXCL16 increased the level of hypoxia‑inducible factor 1α, p-extracellular signal-regulated kinases (ERK), p-p38 and p-Akt dose- and time-dependently. ERK-, p38- and Akt-selective inhibitors significantly suppressed HUVEC proliferation, migration, tube formation and hypoxia-inducible factor 1α (HIF-1α) expression induced by CXCL16. Furthermore, CXCL16 peptides induced CXCL16 secretion via ERK, p38 and Akt pathways, which was suppressed by HIF-1α-selective inhibitor PX12. Our data suggest that CXCL16 induces angiogenesis in autocrine manner via ERK, Akt, p38 pathways and HIF-1α modulation.

The saponin DT-13 inhibits gastric cancer cell migration through down-regulation of CCR5-CCL5 axis

AIM

To investigate the effect of DT-13 on gastric cancer cell migration, and to explore the possible mechanisms underlying the anti-metastasis activity of DT-13.

METHODS

Growth inhibition of DT-13 was analyzed by the MTT assay. Cell migration was measured by the scratch-wound assay and transwell double chamber assay. To investigate the possible mechanisms underlying the anti-metastasis activity of DT-13, chemokine receptors that are involved in cancer metastasis (CCR2, CCR5, CCR7, CXCR4, and CXCR6) were detected by conventional PCR. The effect of DT-13 on CCR5 and CXCR4 expression was further evaluated by quantitative PCR and Western blot, respectively. The secretion of CCL5 (ligand of CCR5) and SDF-1 (ligand of CXCR4) were detected by enzyme-linked immunosorbent assay (ELISA).

RESULTS

DT-13 inhibited BGC-823 and HGC-27 cell growth in a dose dependent manner, and the estimated IC50 value for 24 h treatment was 23.5 ± 5.1 μmol·L(-1) for BGC-823 cells and 35.6 ± 7.6 μmol·L(-1) for HGC-27 cells. DT-13 also significantly decreased gastric cancer cell migration. DT-13 significantly decreased the gene expression of CCR5 in both BGC-823 and HGC-27 gastric cancer cells, and moderately reduced the expression of CXCR4. Similar to the results of gene expression, significant down-regulation of CCR5 protein was observed, but CXCR4 protein levels were much less affected. CCL5 secretion, but not SDF-1 production, was inhibited by DT-13.

CONCLUSION

DT-13 inhibited gastric cancer cell migration by down-regulation of the CCR5-CCL5 axis.

The saponin DT-13 attenuates tumor necrosis factor-α-induced vascular inflammation associated with Src/NF-кB/MAPK pathway modulation

This study aimed to explore the effect of DT-13 (25(R,S)-ruscogenin- 1-O- [β-d-glucopyranosyl- (1→2)][β-d-xylopyranosyl-(1→3)]-β -d- fucopyranoside) on tumor necrosis factor (TNF)-α-induced vascular inflammation and the potential molecular mechanisms. In vitro, DT-13 suppressed TNF-α-induced adhesion and migration of human umbilical vein endothelial cells (HUVECs) by inhibiting the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). DT-13 markedly suppressed NF-кB p65 phosphorylation, and when NF-кB p65 was over-expressed, the inhibitory effect of DT-13 on adhesion molecular decreased. DT-13 also suppressed TNF-α induced luciferase activities of ICAM-1 and VCAM-1 promoter containing NF-κB binding sites. Furthermore, DT-13 markedly suppressed p38 phosphorylation and Src degradation induced by TNF-α, whereas had no significant effect on ERK and JNK activation. In vivo, DT-13 at 4 mg/kg prevented vascular inflammation and the expression of adhesion molecules induced by TNF-α in mice. These findings suggest that DT-13 abrogates vascular inflammation by down-regulating adhesion molecules associated with modulating the NF-кB, p38MAPK, Src signaling pathways, and NF-κB binding site is at least one of the targets of DT-13. This study provides novel information regarding the mechanism by which DT-13 exerts its effects on vascular inflammation, which is important for the onset and progression of various diseases.

DT-13, a saponin of dwarf lilyturf tuber, exhibits anti-cancer activity by down-regulating C-C chemokine receptor type 5 and vascular endothelial growth factor in MDA-MB-435 cells

AIM

To investigate the anticancer activity of DT-13 under normoxia and determine the underlying mechanisms of action.

METHODS

MDA-MB-435 cell proliferation, migration, and adhesion were performed to assess the anticancer activity of DT-13, a saponin from Ophiopogon japonicus, in vitro. In addition, the effects of DT-13 on tumor growth and metastasis in vivo were evaluated by orthotopic implantation of MDA-MB-435 cells into nude mice; mRNA levels of vascular endothelial growth factor (VEGF), C-C chemokine receptor type 5 (CCR5) and hypoxia-inducible factor 1α (HIF-1α) were evaluated by real-time quantitative PCR; and CCR5 protein levels were detected by Western blot assay.

RESULTS

At 0.01 to 1 μmol·L(-1), DT-13 inhibited MDA-MB-435 cell proliferation, migration, and adhesion significantly in vitro. DT-13 reduced VEGF and CCR5 mRNAs, and decreased CCR5 protein expression by down-regulating HIF-1α. In addition, DT-13 inhibited MDA-MB-435 cell lung metastasis, and restricted tumor growth slightly in vivo.

CONCLUSION

DT-13 inhibited MDA-MB-435 cell proliferation, adhesion, and migration in vitro, and lung metastasis in vivo by reducing VEGF, CCR5, and HIF-1α expression.

Saponin monomer 13 of dwarf lilyturf tuber (DT-13) protects serum withdrawal-induced apoptosis through PI3K/Akt in HUVEC

Dwarf lilyturf tuber is widely used in clinics to prevent cardiovascular diseases. DT-13, the saponin monomer 13 of dwarf lilyturf tuber, shows protective activities in anti-thrombosis, anti-inflammation, and cardioprotective. However, little is known about the cellular function of DT-13 in cardiovascular system. Vascular endothelial cells (EC) are important to maintain the integrity of the vasculature throughout entire body. Dysregulation of EC may lead to pathophysiological processes of numerous cardiovascular diseases. We thus tested the function of DT-13 in EC. In the present study, we are the first to report that DT-13 has anti-apoptosis activity on human umbilical vein endothelial cells (HUVEC), potentially through down regulation of cleaved caspase-3 and cleaved PARP expression. DT-13 also increased mitochondrial membrane potential. To explore the potential mechanism, we investigated the effect of DT-13 on Akt and MAPK pathways and found that DT-13 was involved in Akt signaling confirmed by using PI3K/Akt inhibitor LY294002. Thus, DT-13 could improve survival of EC and therefore be a potential clinical use in the treatment of cardiovascular diseases.