Exploring the Neuroprotective Potential of Desmodium Species: Insights into Radical Scavenging Capacity and Mechanisms against 6-OHDA-Induced Neurotoxicity.

In this study, we collected seven prevalent Taiwanese Desmodium plants, including three species with synonymous characteristics, in order to assess their antioxidant phytoconstituents and radical scavenging capacities. Additionally, we compared their inhibitory activities on monoamine oxidase (MAO) and 6-hydroxydopamine (6-OHDA) auto-oxidation. Subsequently, we evaluated the neuroprotective potential of D. pulchellum on 6-OHDA-induced nerve damage in SH-SY5Y cells and delved into the underlying neuroprotective mechanisms. Among the seven Desmodium species, D. pulchellum exhibited the most robust ABTS radical scavenging capacity and relative reducing power; correspondingly, it had the highest total phenolic and phenylpropanoid contents. Meanwhile, D. motorium showcased the best hydrogen peroxide scavenging capacity and, notably, D. sequax demonstrated remarkable prowess in DPPH radical and superoxide scavenging capacity, along with selective inhibitory activity against MAO-B. Of the aforementioned species, D. pulchellum emerged as the frontrunner in inhibiting 6-OHDA auto-oxidation and conferring neuroprotection against 6-OHDA-induced neuronal damage in the SH-SY5Y cells. Furthermore, D. pulchellum effectively mitigated the increase in intracellular ROS and MDA levels through restoring the activities of the intracellular antioxidant defense system. Therefore, we suggest that D. pulchellum possesses neuroprotective effects against 6-OHDA-induced neurotoxicity due to the radical scavenging capacity of its antioxidant phytoconstituents and its ability to restore intracellular antioxidant activities.

PW06 suppresses cancer cell metastasis in human pancreatic carcinoma MIA PaCa-2 cells via the inhibitions of p-Akt/mTOR/NF-κB and MMP2/MMP9 signaling pathways in vitro.

PW06 [(E)-3-(9-ethyl-9H-carbazol-3-yl)-1-(2,5-dimethoxyphenyl) prop-2-en-1-one], a kind of the carbazole derivative containing chalcone moiety, induced cell apoptosis in human pancreatic carcinoma in vitro. There is no investigation to show that PW06 inhibits cancer cell metastasis in human pancreatic carcinoma in vitro. Herein, PW06 (0.1-0.8 µM) significantly exists in the antimetastatic activities of human pancreatic carcinoma MIA PaCa-2 cells in vitro. Wound healing assay shows PW06 at 0.2 µM suppressed cell mobility by 7.45 and 16.55% at 6 and 24 hours of treatments. PW06 at 0.1 and 0.2 µM reduced cell mobility by 14.72 and 21.8% for 48 hours of treatment. Transwell chamber assay indicated PW06 (0.1-0.2 µM) suppressed the cell migration (decreased 26.67-35.42%) and invasion (decreased 48.51-68.66%). Atomic force microscopy assay shows PW06 (0.2 µM) significantly changed the shape of cell morphology. The gelatin zymography assay indicates PW06 decreased MMP2's and MMP9's activities at 48 hours of treatment. Western blotting assay further confirms PW06 reduced levels of MMP2 and MMP9 and increased protein expressions of EGFR, SOS1, and Ras. PW06 also increased the p-JNK, p-ERK, and p-p38. PW06 increased the expression of PI3K, PTEN, Akt, GSK3α/ß, and E-cadherin. Nevertheless, results also show PW06 decreased p-Akt, mTOR, NF-κB, p-GSK3ß, ß-catenin, Snail, N-cadherin, and vimentin in MIA PaCa-2 cells. The confocal laser microscopy examination shows PW06 increased E-cadherin but decreased vimentin in MIA PaCa-2 cells. Together, our findings strongly suggest that PW06 inhibited the p-Akt/mTOR/NF-κB/MMPs pathways, increased E-cadherin, and decreased N-cadherin/vimentin, suppressing the migration and invasion in MIA PaCa-2 cells in vitro.

Puerarin Attenuates Cycloheximide-Induced Oxidative Damage and Memory-Consolidation Impairment in Rats.

BACKGROUND: Cycloheximide (CXM), an antifungal antibiotic, causes impaired memory consolidation as a side effect partially by disturbing the activities of the central catecholaminergic and cholinergic system. Some reports indicated that puerarin prevented memory impairment in various models in rodents. However, the protective effects of puerarin on the side effects of cycloheximide for memory consolidation impairment have not yet been investigated. METHODS: The protective effects of puerarin on CXM-induced memory-consolidation impairment, and memory impairment produced by central administration of AF64A neurotoxin, were investigated using a passive avoidance task in rats. A combination of transmitter receptor agonists and antagonists was used to explore the effects of puerarin on nervous system function. The activity of antioxidant defense systems and neurotransmitter systems in the prefrontal cortex and hippocampus were assayed. RESULTS: Systemic (25 and 50 mg/kg, i.p.) or central (5 and 10 µg/brain, i.c.v.) administration of puerarin attenuated CXM-induced memory-consolidation impairment produced by 1.5 mg/kg CXM (s.c.) in rats. The improvements produced by 50 mg/kg puerarin were blocked by cholinergic antagonists, a 5-HT2 receptor agonist, and an adrenergic receptor antagonist. Puerarin (only at 50 mg/kg, i.p.) reversed the CXM-induced alterations of the levels of norepinephrine in the prefrontal cortex and the levels of monoamines in the hippocampus. Puerarin also increased antioxidant-defense-system activities in the prefrontal cortex and hippocampus, which had been decreased by CXM. CONCLUSIONS: We suggested that the attenuating effects of puerarin on CXM-induced memory-consolidation impairment may be due to decrease oxidative damage and the normalition of the neurotransmitter function in the prefrontal cortex and hippocampus.

PW06 Triggered Fas-FADD to Induce Apoptotic Cell Death In Human Pancreatic Carcinoma MIA PaCa-2 Cells through the Activation of the Caspase-Mediated Pathway.

Pancreatic cancer has higher incidence and mortality rates worldwide. PW06 [(E)-3-(9-ethyl-9H-carbazol-3-yl)-1-(2,5-dimethoxyphenyl) prop-2-en-1-one] is a carbazole derivative containing chalcone moiety which was designed for inhibiting tumorigenesis in human pancreatic cancer. This study is aimed at investigating PW06-induced anticancer effects in human pancreatic cancer MIA PaCa-2 cells in vitro. The results showed PW06 potent antiproliferative/cytotoxic activities and induced cell morphological changes in a human pancreatic cancer cell line (MIA PaCa-2), and these effects are concentration-dependent (IC50 is 0.43 µM). Annexin V and DAPI staining assays indicated that PW06 induced apoptotic cell death and DNA condensation. Western blotting indicated that PW06 increased the proapoptotic proteins such as Bak and Bad but decreased the antiapoptotic protein such as Bcl-2 and Bcl-xL. Moreover, PW06 increased the active form of caspase-8, caspase-9, and caspase-3, PARP, releasing cytochrome c, AIF, and Endo G from mitochondria in MIA PaCa-2 cells. Confocal laser microscopy assay also confirmed that PW06 increased Bak and decreased Bcl-xL. Also, the cells were pretreated with inhibitors of caspase-3, caspase-8, and caspase-9 and then were treated with PW06, resulting in increased viable cell number compared to PW06 treated only. Furthermore, PW06 showed a potent binding ability with hydrophobic interactions in the core site of the Fas-Fas death domains (FADD). In conclusion, PW06 can potent binding ability to the Fas-FADD which led to antiproliferative, cytotoxic activities, and apoptosis induction accompanied by the caspase-dependent and mitochondria-dependent pathways in human pancreatic cancer MIA PaCa-2 cells.

Therapeutic Potential and Mechanisms of Novel Simple O-Substituted Isoflavones against Cerebral Ischemia Reperfusion.

Isoflavones have been widely studied and have attracted extensive attention in fields ranging from chemotaxonomy and plant physiology to human nutrition and medicine. Isoflavones are often divided into three subgroups: simple O-substituted derivatives, prenylated derivatives, and glycosides. Simple O-substituted isoflavones and their glycosides, such as daidzein (daidzin), genistein (genistin), glycitein (glycitin), biochanin A (astroside), and formononetin (ononin), are the most common ingredients in legumes and are considered as phytoestrogens for daily dietary hormone replacement therapy due to their structural similarity to 17-ß-estradiol. On the basis of the known estrogen-like potency, these above isoflavones possess multiple pharmacological activities such as antioxidant, anti-inflammatory, anticancer, anti-angiogenetic, hepatoprotective, antidiabetic, antilipidemic, anti-osteoporotic, and neuroprotective activities. However, there are very few review studies on the protective effects of these novel isoflavones and their related compounds in cerebral ischemia reperfusion. This review primarily focuses on the biosynthesis, metabolism, and neuroprotective mechanism of these aforementioned novel isoflavones in cerebral ischemia reperfusion. From these published works in in vitro and in vivo studies, simple O-substituted isoflavones could serve as promising therapeutic compounds for the prevention and treatment of cerebral ischemia reperfusion via their estrogenic receptor properties and neuron-modulatory, antioxidant, anti-inflammatory, and anti-apoptotic effects. The detailed mechanism of the protective effects of simple O-substituted isoflavones against cerebral ischemia reperfusion might be related to the PI3K/AKT/ERK/mTOR or GSK-3ß pathway, eNOS/Keap1/Nrf-2/HO-1 pathway, TLRs/TIRAP/MyD88/NFκ-B pathway, and Bcl-2-regulated anti-apoptotic pathway. However, clinical trials are needed to verify their potential on cerebral ischemia reperfusion because past studies were conducted with rodents and prophylactic administration.

Anti-Angiogenetic and Anti-Lymphangiogenic Effects of a Novel 2-Aminobenzimidazole Derivative, MFB.

Background and Purpose: Benzimidazoles have attracted much attention over the last few decades due to their broad-spectrum pharmacological properties. Increasing evidence is showing the potential use of benzimidazoles as anti-angiogenic agents, although the mechanisms that impact angiogenesis remain to be fully defined. In this study, we aim to investigate the anti-angiogenic mechanisms of MFB, a novel 2-aminobenzimidazole derivative, to develop a novel angiogenesis inhibitor. Experimental Approach: MTT, BrdU, migration and invasion assays, and immunoblotting were employed to examine MFB's effects on vascular endothelial growth factor (VEGF)-induced endothelial cell proliferation, migration, invasion, as well as signaling molecules activation. The anti-angiogenic effects of MFB were analyzed by tube formation, aorta ring sprouting, and matrigel plug assays. We also used a mouse model of lung metastasis to determine the MFB's anti-metastatic effects. Key Results: MFB suppressed cell proliferation, migration, invasion, and endothelial tube formation of VEGF-A-stimulated human umbilical vascular endothelial cells (HUVECs) or VEGF-C-stimulated lymphatic endothelial cells (LECs). MFB suppressed VEGF-A and VEGF-C signaling in HUVECs or LECs. In addition, MFB reduced VEGF-A- or tumor cells-induced neovascularization in vivo. MFB also diminished B16F10 melanoma lung metastasis. The molecular docking results further showed that MFB may bind to VEGFR-2 rather than VEGF-A with high affinity. Conclusions and Implications: These observations indicated that MFB may target VEGF/VEGFR signaling to suppress angiogenesis and lymphangiogenesis. It also supports the role of MFB as a potential lead in developing novel agents for the treatment of angiogenesis- or lymphangiogenesis-associated diseases and cancer.

Suppressing VEGF-A/VEGFR-2 Signaling Contributes to the Anti-Angiogenic Effects of PPE8, a Novel Naphthoquinone-Based Compound.

Natural naphthoquinones and their derivatives exhibit a broad spectrum of pharmacological activities and have thus attracted much attention in modern drug discovery. However, it remains unclear whether naphthoquinones are potential drug candidates for anti-angiogenic agents. The aim of this study was to evaluate the anti-angiogenic properties of a novel naphthoquinone derivative, PPE8, and explore its underlying mechanisms. Determined by various assays including BrdU, migration, invasion, and tube formation analyses, PPE8 treatment resulted in the reduction of VEGF-A-induced proliferation, migration, and invasion, as well as tube formation in human umbilical vein endothelial cells (HUVECs). We also used an aorta ring sprouting assay, Matrigel plug assay, and immunoblotting analysis to examine PPE8's ex vivo and in vivo anti-angiogenic activities and its actions on VEGF-A signaling. It has been revealed that PPE8 inhibited VEGF-A-induced micro vessel sprouting and was capable of suppressing angiogenesis in in vivo models. In addition, PPE8 inhibited VEGF receptor (VEGFR)-2, Src, FAK, ERK1/2, or AKT phosphorylation in HUVECs exposed to VEGF-A, and it also showed significant decline in xenograft tumor growth in vivo. Taken together, these observations indicated that PPE8 may target VEGF-A-VEGFR-2 signaling to reduce angiogenesis. It also supports the role of PPE8 as a potential drug candidate for the development of therapeutic agents in the treatment of angiogenesis-related diseases including cancer.

Bisdemethoxycurcumin suppresses human brain glioblastoma multiforme GBM 8401 cell migration and invasion via affecting NF-κB and MMP-2 and MMP-9 signaling pathway in vitro.

Human glioblastoma (GBM) is one of the common cancer death in adults worldwide, and its metastasis will lead to difficult treatment. Finding compounds for future to develop treatment is urgent. Bisdemethoxycurcumin (BDMC), a natural product, was isolated from the rhizome of turmeric (Curcuma longa), which has been shown to against many human cancer cells. In the present study, we evaluated the antimetastasis activity of BDMC in human GBM cells. Cell proliferation, cell viability, cellular uptake, wound healing, migration and invasion, and western blotting were analyzed. Results indicated that BDMC at 1.5-3 µM significantly decreased the cell proliferation by MTT assay. BDMC showed the highest uptake by cells at 3 h. After treatment of BDMC at 12-48 h significantly inhibited cell motility in GBM 8401 cells by wound healing assay. BDMC suppressed cell migration and invasion at 24 and 48 h treatment by transwell chamber assay. BDMC significantly decreased the levels of proteins associated with PI3K/Akt, Ras/MEK/ERK pathways and resulted in the decrease in the expressions of NF-κB, MMP-2, MMP-9, and N-cadherin, leading to the inhibition of cell migration and invasion. These findings suggest that BDMC may be a potential candidate for the antimetastasis of human GBM cells in the future.

Tetrandrine Suppresses Human Brain Glioblastoma GBM 8401/luc2 Cell-Xenografted Subcutaneous Tumors in Nude Mice In Vivo.

Tetrandrine (TET), a bisbenzylisoquinoline (BBI) alkaloid, is isolated from the plant Stephania tetrandra S. Moore and has a wide range of biological activity, including anticancer properties in vitro and in vivo. At first, we established a luciferase-expressing stable clone that was named GBM 8401/luc2 cells. Herein, the primary results indicated that TET reduced the total cell viability and induced cell apoptosis in GBM 8401/luc2 human glioblastoma cells. However, there is no available information showing that TET suppresses glioblastoma cells in vivo. Thus, we investigated the effects and mechanisms of TET on a GBM 8401/luc2 cell-generated tumor in vivo. After the tumor volume reached 100-120 mm3 in subcutaneously xenografted nude mice, all of the mice were randomly divided into three groups: Group I was treated with phosphate-buffered solution (PBS) containing 0.1% dimethyl sulfoxide, Group II with 25 mg/kg of TET, and Group III with 50 mg/kg of TET. All mice were given the oral treatment of PBS or TET by gavage for 21 days, and the body weight and tumor volumes were recorded every 5 days. After treatment, individual tumors, kidneys, livers, and spleens were isolated from each group. The results showed that TET did not affect the body weights, but it significantly decreased the tumor volumes. The TET treatment at 50 mg/kg had a two-fold decrease in tumor volumes than that at 25 mg/kg when compared to the control. TET decreased the total photon flux, and treatment with TET at 50 mg/kg had a lower total photon flux than that at 25 mg/kg, as measured by a Xenogen IVIS imaging system. Moreover, the higher TET treatment had lower tumor volumes and weights than those of the lower dose. The apoptosis-associated protein expression in the tumor section was examined by immunohistochemical analysis, and the results showed that TET treatment reduced the levels of c-FLIP, MCL-1, and XIAP but increased the signals of cleaved-caspase-3, -8, and -9. Furthermore, the hematoxylin and eosin (H & E) staining of kidney, liver, and spleen tissues showed no significant difference between the TET-treated and control groups. Overall, these observations demonstrated that TET suppressed subcutaneous tumor growth in a nude-mice model via the induction of cell apoptosis.

Synthetic Tryptanthrin Derivatives Induce Cell Cycle Arrest and Apoptosis via Akt and MAPKs in Human Hepatocellular Carcinoma Cells.

Trytanthrin, found in Ban-Lan-Gen, is a natural product containing an indoloquinazoline moiety and has been shown to possess anti-inflammatory and anti-viral activities. Chronic inflammation and hepatitis B are known to be associated with the progression of hepatocellular carcinoma (HCC). In this study, a series of tryptanthrin derivatives were synthesized to generate potent anti-tumor agents against HCC. This effort yielded two compounds, A1 and A6, that exhibited multi-fold higher cytotoxicity in HCC cells than the parent compound. Flow cytometric analysis demonstrated that A1 and A6 caused S-phase arrest and downregulated the expression of cyclin A1, B1, CDK2, and p-CDC2. In addition to inducing caspase-dependent apoptosis, A1 and A6 exhibited similar regulation of the phosphorylation or expression of multiple signaling targets, including Akt, NF-κB, and mitogen-activated protein kinases. The anti-tumor activities of A1 and A6 were also attributable to the generation of reactive oxygen species, accompanied by an increase in p-p53 levels. Therefore, A1 and A6 have potential clinical applications since they target diverse aspects of cancer cell growth in HCC.

Design, Synthesis and Evaluation of Novel Derivatives of Curcuminoids with Cytotoxicity.

Curcumin and curcuminoids have been discussed frequently due to their promising functional groups (such as scaffolds of α,ß-unsaturated ß-diketone, α,ß-unsaturated ketone and ß'-hydroxy-α,ß-unsaturated ketone connected with aromatic rings on both sides) that play an important role in various bioactivities, including antioxidant, anti-inflammatory, anti-proliferation and anticancer activity. A series of novel curcuminoid derivatives (a total of 55 new compounds) and three reference compounds were synthesized with good yields using three-step organic synthesis. The anti-proliferative activities of curcumin derivatives were examined for six human cancer cell lines: HeLaS3, KBvin, MCF-7, HepG2, NCI-H460 and NCI-H460/MX20. Compared to the IC50 values of all the synthesized derivatives, most α,ß-unsaturated ketones displayed potent anti-proliferative effects against all six human cancer cell lines, whereas ß'-hydroxy-α,ß-unsaturated ketones and α,ß-unsaturated ß-diketones presented moderate anti-proliferative effects. Two potent curcuminoid derivatives were found among all the novel derivatives and reference compounds: (E)-5-hydroxy-7-phenyl-1-(3,4,5-trimethoxyphenyl)hept-1-en-3-one (compound 3) and (1E,4E)-1,7-bis(3,4,5-trimethoxyphenyl)hepta-1,4-dien-3-one (compound MD12a). These were selected for further analysis after the evaluation of their anti-proliferative effects against all human cancer cell lines. The results of apoptosis assays revealed that the number of dead cells was increased in early apoptosis and late apoptosis, while cell proliferation was also decreased after applying various concentrations of (E)-5-hydroxy-7-phenyl-1-(3,4,5-trimethoxyphenyl)hept-1-en-3-one (compound 3) and (1E,4E)-1,7-bis(3,4,5-trimethoxyphenyl)hepta-1,4-dien-3-one (compound MD12a) to MCF-7 and HpeG2 cancer cells. Analysis of the gene expression arrays showed that three genes (GADD45B, SESN2 and BBC3) were correlated with the p53 pathway. From the quantitative PCR analysis, it was seen that (1E,4E)-1,7-bis(3,4,5-trimethoxyphenyl)hepta-1,4-dien-3-one (compound MD12a) effectively induced the up-regulated expression of GADD45B, leading to the suppression of MCF-7 cancer cell formation and cell death. Molecular docking analysis was used to predict and sketch the interactions of the GADD45B-α,ß-unsaturated ketone complex for help in drug design.

Demethoxycurcumin Promotes Macrophage Cell Population and Phagocytosis in WEHI-3 Cell-generated Leukemia BALB/c Mice In Vivo.

BACKGROUND/AIM: Demethoxycurcumin (DMC), one of the components of curcuminoids, has antitumor activities in many human cancer cells and is known to induce apoptosis in human leukemia cells. However, there are no reports showing the effects of DMC on the immune response in leukemia mice in vivo. Herein, we evaluated the impact of DMC on immune responses in WEHI-3-generated leukemia mice in vivo. MATERIALS AND METHODS: Fifty male BALB/c mice were separated randomly into five groups. Group I is normal mice, and groups II-V mice of generated leukemia by WEHI-3 cells. Group II-V mice were intraperitoneally injected with dimethyl sulfoxide (DMSO, as the positive control), 15, 30, and 60 mg/kg of DMC, respectively, every two days for 14 days. The body weight, blood, peritoneal fluid, liver, and spleen were individually analyzed. RESULTS: DMC did not significantly affect animal appearance and body weight. It decreased liver and spleen weight at a high dose. DMC did not affect the cluster of differentiation 3 (CD3) and CD19 cell populations but induced decrease of CD11b at 30 mg/kg treatment. However, DMC at low dose significantly increased the cluster of macrophage (Mac-3) cell populations, but at high dose it decreased them. DMC increased macrophage phagocytosis from peripheral blood mononuclear cells at 15 mg/kg treatment and peritoneal cavity at 15, 30 and 60 mg/kg of DMC treatments. DMC did not significantly affect the cytotoxic activity of natural killer (NK) cells. Furthermore, DMC decreased B and T cell proliferation at high doses. CONCLUSION: DMC elevated macrophage phagocytosis in leukemia mice in vivo.

Allyl Isothiocyanate Induces DNA Damage and Impairs DNA Repair in Human Breast Cancer MCF-7 Cells.

BACKGROUND/AIM: Ally lisothiocyanate (AITC), a constituent of naturally occurring isothiocyanates (ITCs) found in some Brassica vegetables, has been previously demonstrated to have anti-carcinogenic activity. However, there is no available information showing that AITC induces DNA damage and alters DNA damage repair proteins in human breast cancer MCF-7 cells. MATERIALS AND METHODS: In the present study, we investigated the effects of AITC on DNA damage and repair responses in human breast cancer MCF-7 cells in vitro. Cell viability was measured by flow cytometric assay. DNA condensation (apoptotic cell death) and DNA fragmentation (laddered DNA) were assayed by DAPI staining and DNA gel electrophoresis assays, respectively. Furthermore, DNA damage (comet tail) was measured by the comet assay. Western blotting was used to measure the expression of DNA damage- and repair-associated proteins. RESULTS: AITC decreased cell viability in a dose-dependent and induced apoptotic cell death (DNA condensation and fragmentation) and DNA damage in MCF-7 cells. AITC increased p-ATMSer1981, p-ATRSer428, p53, p-p53Ser15, p-H2A.XSer139, BRCA1, and PARP at 10-30 µM at 24 and 48 h treatments. However, AITC decreased DNA-PK at 24 and 48 h treatment, and decreased MGMT at 48 h in MCF-7 cells. CONCLUSION: AITC induced cytotoxic effects (decreased viable cell number) through induction of DNA damage and condensation and altered DNA damage and repair associated proteins in MCF-7 cells in vitro.

Ouabain Suppresses Cell Migration and Invasion in Human Gastric Cancer AGS Cells Through the Inhibition of MMP Signaling Pathways.

BACKGROUND/AIM: Ouabain has been shown to induce human cancer cell death via apoptosis. Still, its anti-metastatic effect on cell migration and invasion of human gastric cancer cells has not been addressed. MATERIALS AND METHODS: Cell proliferation and viability were measured by the MTT assay and flow cytometry, respectively. Cell motitlity was analysed by wound healing assay. Cell migration and invasion were analysed by the transwell system. Protein expression was assayed by western blotting. RESULTS: Ouabain decreased AGS cell proliferation, cell viability, and motility. In addition, ouabain inhibited AGS cell migration and invasion. Furthermore, ouabain decreased matrix metalloproteinase-2 (MMP-2) activity at 48 h. Ouabain reduced the levels of proteins associated with PI3K/AKT and p38/MAPK pathways. In addition, ouabain decreased the expressions of N-cadherin, tissue inhibitor of metalloproteinases-1 (TIMP-1), urokinase-type plasminogen activator (c-uPA), and MMP-2 at 48 h. CONCLUSION: Ouabain suppresses cell metastasis through multiple signaling pathways in AGS cells.

Antioxidant Effects and Phytochemical Properties of Seven Taiwanese Cirsium Species Extracts.

In the present investigation, we compared the radical-scavenging activities and phenolic contents of seven Taiwanese Cirsium species with a spectrophotometric method. We further analyzed their phytochemical profiles with high-performance liquid chromatography-photodiode array detection (HPLC-DAD). We found that the flower part of Cirsium japonicum var. australe (CJF) showed the best radical-scavenging activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and the hypochlorite ion, for which the equivalents were 6.44 ± 0.17 mg catechin/g, 54.85 ± 0.66 mmol Trolox/g and 418.69 ± 10.52 mmol Trolox/g respectively. CJF also had the highest contents of total phenolics (5.23 ± 0.20 mg catechin/g) and phenylpropanoids (29.73 ± 0.72 mg verbascoside/g). According to the Pearson's correlation coefficient, there was a positive correlation between the total phenylpropanoid content and ABTS radical-scavenging activities (r = 0.979). The radical-scavenging activities of the phenylpropanoids are closely related to their reducing power (r = 0.986). HPLC chromatograms obtained in validated HPLC conditions confirm that they have different phytochemical profiles by which they can be distinguished. Only CJF contained silicristin (0.66 ± 0.03 mg/g) and silydianin (9.13 ± 0.30 mg/g). CJF contained the highest contents of apigenin (5.56 ± 0.09 mg/g) and diosmetin (2.82 ± 0.10 mg/g). Among the major constituents, silicristin had the best radical-scavenging activities against DPPH (71.68 ± 0.66 mg catechin/g) and ABTS (3.01 ± 0.01 mmol Trolox/g). However, diosmetin had the best reducing power and radical-scavenging activity against the hypochlorite anion (41.57 ± 1.14 mg mmol Trolox/g). Finally, we found that flavonolignans (especial silicristin and silydianin) and diosmetin acted synergistically in scavenging radicals.

Demethoxycurcumin Suppresses Proliferation, Migration, and Invasion of Human Brain Glioblastoma Multiforme GBM 8401 Cells via PI3K/Akt Pathway.

BACKGROUND/AIM: Demethoxycurcumin (DMC), one of the derivatives of curcumin, has been shown to induce apoptotic cell death in many human cancer cell lines. However, there is no available information on whether DMC inhibits metastatic activity in human glioblastoma cancer cells in vitro. MATERIALS AND METHODS: DMC at 1.0-3.0 µM significantly decreased the proliferation of GBM 8401 cells; thus, we used 2.0 µM for further investigation regarding anti-metastatic activity in human glioblastoma GBM 8401 cells. RESULTS: The internalized amount of DMC has reached the highest level in GBM 8401 cells after 3 h treatment. Wound healing assay was used to determine cell mobility and results indicated that DMC suppressed cell movement of GBM 8401 cells. The transwell chamber assays were used for measuring cell migration and invasion and results indicated that DMC suppressed cell migration and invasion in GBM 8401 cells. Gelatin zymography assay was used to examine gelatinolytic activity (MMP-2) in conditioned media of GBM 8401 cells treated by DMC and results demonstrated that DMC significantly reduced MMP-2 activity. Western blotting showed that DMC reduced the levels of p-EGFR(Tyr1068), GRB2, Sos1, p-Raf, MEK, p-ERK1/2, PI3K, p-Akt/PKBα(Thr308), p-PDK1, NF-κB, TIMP-1, MMP-9, MMP-2, GSK3α/ß, ß-catenin, N-cadherin, and vimentin, but it elevated Ras and E-cadherin at 24 h treatment. CONCLUSION: DMC inhibited cancer cell migration and invasion through inhibition of PI3K/Akt and NF-κB signaling pathways in GBM 8401 cells. We suggest that DMC may be used as a novel anti-metastasis agent for the treatment of human glioblastoma cancer in the future.

Molecular interaction of cytotoxic anticancer analogues as inhibitors of ß-tubulin protein against UACC-62 melanoma cell.

In previous research, a series of cytotoxic anticancer analogues related to 2-acylamino-1,4-naphthoquinone derivatives has been demonstrated. As microtubule plays an important role in many essential cellular processes such as mitosis, tubulin is an important target of anticancer drug. This study performed molecular docking simulation, pharmacophore model, comparative force field analysis model and comparative similarity indices analysis model to investigate the relationship between inhibitory activities and the properties of compounds, in order to further progress the development of cytotoxic anticancer analogues. These compounds have common H-bond interactions with key residues Lys254 and Lys352, but compounds with large R2 substituent have different docking poses than compounds with small R2 substituent. Some of derivatives such as compound 18 formed the H-bonds with residue Lys254 using the oxygen atoms in R1 substituent and formed π-cation interactions with residue Lys352 using phenyl moiety of 1,4-naphthoquinone. The R1 substituent of these compounds preferred to have disfavoured hydrophobic fields and favourable space towards the direction of residue Asn258, while the R2 substituent of these compounds preferred to have about 2-3 carbon chain length hydrophobic substituent towards the direction of residues Ala316 and Lys352. These results offer some beneficial advices for further study in anticancer drug development process.

Genistein enhances the effects of L-asparaginase on inducing cell apoptosis in human leukemia cancer HL-60 cells.

Genistein (GEN) has been shown to induce apoptotic cell death in various human cancer cells. L-asparaginase (Asp), a clinical drug for leukemia, has been shown to induce cell apoptosis in leukemia cells. No available information concerning GEN combined with Asp increased the cell apoptosis compared to GEN or Asp treatment alone. The objective of this study is to evaluate the anti-leukemia activity of GEN combined with Asp on human leukemia HL-60 cells in vitro. The cell viability, the distribution of cell cycle, apoptotic cell death, and the level of ΔΨm were examined by flow cytometric assay. The expressions of apoptosis-associated proteins were measured by western blotting. GEN combined with Asp revealed a more significant decrease in total viable cells and induced a higher percentage of G2/M phase arrest, DNA damage, and cell apoptosis than that of GEN or Asp treatment only in HL-60 cells. Furthermore, the combined treatments (GEN and Asp) showed a higher decrease in the level of ΔΨm than that of GEN or Asp treatment only. These results indicated that GEN combined with Asp induced mitochondria dysfunction by disrupting the mitochondrial membrane potential. The results from western blotting demonstrated that the treatment of GEN combined with Asp showed a higher increase in the levels of Bax and Bak (pro-apoptotic proteins) and an active form of caspase-3 and a higher decrease in Bcl-2 (anti-apoptotic protein) than that of GEN or Asp treatment alone. GEN significantly enhances the efficiency of Asp on cytotoxic effects (the induction of apoptosis) in HL-60 cells.

Maslinic Acid Induces DNA Damage and Impairs DNA Repair in Human Cervical Cancer HeLa Cells.

BACKGROUND/AIM: Maslinic acid, a natural plant-derived triterpenoid compound, exhibits pharmacological activities, including anti-cancer. In the present study, we investigated the cytotoxic effects of maslinic acid on human cervical cancer HeLa cells in vitro and further investigated the molecular mechanism of maslinic acid-induced DNA damage and repair. MATERIALS AND METHODS: Cell viability was measured by flow cytometry. DNA condensation (apoptotic cell death), DNA damage, and DNA fragmentation (DNA ladder) were assayed by DAPI staining, comet assay, and agarose gel electrophoresis, respectively. The expression of DNA damage and repair proteins was assayed by western blotting. RESULTS: Maslinic acid decreased total cell viability and induced DNA condensation, damage, and fragmentation in HeLa cells. Furthermore, maslinic acid elevated the levels of p-ATMSer1981, p-ATRSer428, p53, p-p53Ser151, p-H2A.XSer139, BRCA1 and PARP at 30-40 µM. However, it decreased the levels of DNA-PK and MGMT. CONCLUSION: Maslinic acid reduced the number of viable HeLa cells by inducing DNA damage and altering the expression of proteins involved in DNA damage and repair.

Demethoxycurcumin Inhibits In Vivo Growth of Xenograft Tumors of Human Cervical Cancer Cells.

BACKGROUND/AIM: Demethoxycurcumin (DMC), a derivate of curcumin from natural plants, exerts antitumor effects on various human cancer cells in vitro and in vivo. Nevertheless, no reports have disclosed whether DMC can affect the growth of human cervical cancer cells in vivo. Therefore we investigated the antitumor effects of DMC on a HeLa cell xenograft model in nude mice in this study. MATERIALS AND METHODS: Twenty-four nude mice were subcutaneously injected with HeLa cells. All mice were randomly divided into control, low-dose DMC (30 mg/kg), and high-dose DMC (50 mg/kg) groups and individual mice were treated intraperitoneally accordingly every 2 days. RESULTS: DMC significantly reduced tumor weights and volumes of HeLa cell xenografts in mice, indicating the suppression of growth of xenograft tumors. CONCLUSION: These effects and findings might provide evidence for investigating the potential use of DMC as an anti-cervical cancer drug in the future.