hypericum and Glioblastoma

Glioblastoma is the most common primary brain tumor with poor survival rate and without effective treatment strategy. Notably, amplification and active mutation of epidermal growth factor receptor (EGFR) occur frequently in glioblastoma patient that may be a potential treatment target. Several studies indicated that various type of herbal compounds not only regulate anti-depressant effect but also shown capacity to suppress glioblastoma growth via inducing apoptosis and inhibiting oncogene signaling transduction. Hyperforin, an herb compound derived from St. John's wort was used to treat depressive disorder by inhibiting neuronal reuptake of several neurotransmitters. Although hyperforin can reduce matrix metallopeptidases-2 (MMPs) and -9-mediated metastasis of glioblastoma, the detail mechanism of hyperforin on glioblastoma is remaining unclear. Here, we suggested that hyperforin may induce extrinsic/intrinsic apoptosis and suppress anti-apoptotic related proteins expression of glioblastoma. We also indicated that hyperforin-mediated anti-apoptotic potential of glioblastoma was correlated to inactivation of EGFR/extracellular signal-regulated kinases (ERK)/nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling.

Topics: Antineoplastic Agents, Phytogenic; Apoptosis; Apoptosis Regulatory Proteins; Brain Neoplasms; Cell Line, Tumor; Cell Survival; ErbB Receptors; Extracellular Signal-Regulated MAP Kinases; Glioblastoma; Humans; Hypericum; Phloroglucinol; Signal Transduction; Terpenes; Transcription Factor RelA

Chronic stress, an important factor in the development of depressive disorders, leads to an increased formation of cortisol, which causes a hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis. In addition, cortisol mediates an adaptive effect on plasma membrane fluidity which may affect signal transduction of membrane-bound receptors and contribute to pathophysiological changes.. Membrane fluidity was measured by fluorescence anisotropy using DPH (1,6-diphenyl-1,3,5-hexatriene) and TMA-DPH (1-(4-(trimethylamino)phenyl)-6-phenylhexa-1,3,5-triene). Changes in cellular content of phosphatidylcholine species was determined by pulse-chase experiments using deuterated choline and mass spectrometry. Single molecule tracking was used to examine the lateral mobility of β1-adrenoceptors and changes in cAMP formation were measured by ELISA.. Chronic exposure (6 - 8 days) of C6 cells to cortisol dose-dependently decreased DPH and TMA-DPH fluorescence anisotropy, reflecting increased membrane fluidity. In contrast, cells pretreated with St. John's wort extract Ze117 showed increased DPH and TMA-DPH fluorescence anisotropy values, indicating a membrane rigidification effect which was mediated at least by the constituents hypericin, hyperforin, quercetin, amentoflavone and biapigenin. The observed membrane fluidizing effect of cortisol could be reversed by cotreatment with Ze117. The membrane rigidification of Ze117 was in line with the in parallel observed decrease in the phosphatidylcholine/phosphatidylethanolamine ratio determined in whole cell lipid extracts. Interestingly, pulse-chase experiments demonstrated, that Ze117 inhibited the incorporation of choline-D9 in phosphatidylcholine species with saturated or monounsaturated fatty acids compared to control cells, while the synthesis of phosphatidylcholine species with polyunsaturated fatty acids was not affected. C6 cells whose membranes have become more rigid by Ze117 showed altered lateral mobility of β1-adrenoceptors as well as reduced cAMP formation after stimulation with the β1-adrenoceptor agonist dobutamine.. Obviously, the signaling of β1-adrenoceptors depends on the nature of the membrane environment. It can therefore be assumed that Ze117 has a normalizing effect not only on the membrane fluidity of "stressed" cells, but also on lateral mobility and subsequently on the signal transduction of membrane-associated receptors.

Topics: Animals; Anthracenes; Cell Line, Tumor; Cell Membrane; Glioblastoma; Hydrocortisone; Hypericum; Membrane Fluidity; Perylene; Phloroglucinol; Phosphatidylethanolamines; Plant Extracts; Quercetin; Rats; Receptors, Adrenergic, beta-1; Signal Transduction; Terpenes

Cytotoxic activity of 16 Hypericum ethanolic extracts was evaluated by MTT assay on two human cancer cell lines: glioblastoma A1235 and breast cancer MDA MB-231. Morphology and the type of induced cell death were determined using light and fluorescence microscopy. The majority of Hypericum extracts had no significant cytotoxic effect on MDA MB-231 cells. Eight extracts exhibited mild cytotoxic effect on A1235 cells after 24 h incubation, ranging from 8.0% (H. patulum) to 21.7% (H. oblongifolium). After 72 h of treatment, the strongest inhibition of A1235 viability was observed for extracts of H. androsaemum (26.4-43.9%), H. balearicum (25.8-36.3%), H. delphicum (14.8-27.4%) and H. densiflorum (11.2-24.1%). Micro-scopic examination of cells showed apoptosis as the dominant type of cell death. Due to observed high viability of treated cells, we propose that cytotoxic effects of Hypericum extracts could be related to alternations/interruptions in the cell cycle.

Topics: Antineoplastic Agents; Apoptosis; Breast Neoplasms; Cell Line, Tumor; Cell Survival; Glioblastoma; Humans; Hypericum; Plant Extracts

Propolis and Hypericum perforatum L. are natural products which contain many active compounds and have numerous beneficial effects, including an antitumor effect. Gliobmastoma multiforme (GBM) is a common primary brain tumor with poor prognosis and limited treatment options. In this study, the effect of propolis (EEP) combined with H. perforatum L. (HPE) on glioblastoma cell line U87MG was investigated for the first time.. Anti-proliferative activity of EEP, HPE and their combination (EEP + HPE) was determined by a cytotoxicity test, DNA binding by [(3)H]-thymidine incorporation and cell migration assay. Anti-metastatic properties in U87MG treated with EEP, HPE and EEP + HPE were estimated on cells migration test (scratch assay) and metalloproteinases (MMP2 and MMP9) secretion (gelatin zymography).. Combination of HPE and EEP extracts was found to have a time- and dose-dependent inhibitory effect on the viability of U87MG cells. This effect was significantly higher (p < 0.05) when compared to these two extracts applied separately, which was confirmed by the significant reduction of DNA synthesis and significantly higher mitochondrial membrane permeabilization. A significant decreasing in migration cells and in pro-MMP9 and pro-MMP2 secretion in U87MG cells were demonstrated after exposure to combination of EEP (30 μg/ml) with HPE (6.25 μg/ml).. In this study, the combination of ethanolic extract from propolis and ethanolic extract of fresh-cut H. perforatum L. was proved the ability to reduce invasiveness of glioma cells through the inhibition of MMP2 and MMP9 secretion and suppression of cell migration. It has a more potent anti-proliferative effect on U87MG glioma cell line compared to using propolis and H. perforatum L. separately. Further studies are required to verify whether the examined extracts can activate apoptotic pathways.

Topics: Antineoplastic Agents; Cell Line, Tumor; Cell Movement; Cell Proliferation; Glioblastoma; Humans; Hypericum; Plant Extracts; Propolis

While the use of St John's wort extracts as treatment for mild to moderate depression is well established the mode of action is still under investigation. Individual constituents of St John's wort extract were tested for possible effects on the β1 AR density and a subsequent change in downstream signalling in rat C6 glioblastoma cells.. The effect of compounds from St John's wort extract on the downregulation of β1 -adrenergic receptor-GFP fusion proteins (β1 AR-green fluorescent protein (GFP)) of transfected rat C6 gliobastoma cells (C6-β1 AR-GFP) was investigated by means of confocal laser scanning microscopy (LSM). The influence on the lateral mobility of β1 AR-GFP in C6-β1 AR-GFP was investigated by fluorescence correlation spectroscopy. The formation of second messenger was determined by c-AMP-assay.. Confocal LSM revealed that pretreatment of cells with 1 μm of hyperforin and hyperoside for 6 days, respectively, led to an internalization of β1 AR-GFP under non-stimulating conditions. Observation by fluorescence correlation spectroscopy showed two diffusion time constants for control cells, with τdiff1  = 0.78 ± 0.18 ms and τdiff2  = 122.53 ± 69.41 ms, similarly distributed. Pretreatment with 1 μm hyperforin or 1 μm hyperoside for 3 days did not alter the τdiff values but decreased the fraction of τdiff1 whereas the fraction of τdiff2 increased significantly. An elevated level of β1 AR-GFP with hindered lateral mobility was in line with β1 AR-GFP internalization induced by hyperforin and hyperoside, respectively. A reduced β1 -adrenergic responsiveness was assumed for C6 gliobastoma cells after pretreatment for 6 days with 1 μm of both hyperforin and hyperoside, which was confirmed by decreased cAMP formation of about 10% and 5% under non-stimulating conditions. Decrease in cAMP formation by 23% for hyperforin and 15% for hyperoside was more pronounced after stimulation with 10 μm dobutamine for 30 min.. The treatment of C6 gliobastoma cells with hyperforin and hyperoside results in a reduced β1 AR density in the plasma membrane and a subsequent reduced downstream signalling.

Topics: Animals; Cell Line, Tumor; Cell Membrane; Cyclic AMP; Down-Regulation; Glioblastoma; Hypericum; Phloroglucinol; Plant Extracts; Quercetin; Rats; Receptors, Adrenergic, beta-1; Terpenes

Malignant gliomas are a highly aggressive type of brain tumor with extremely poor prognosis. These tumors are highly invasive and are often surgically incurable and resistant to chemotherapeutics and radiotherapy. Thus, novel therapies that target pathways involved in growth and survival of the tumor cells are required for the treatment of this class of brain tumors. Previous studies revealed that epidermal growth factor receptor and extracellular-signal-regulated kinases (ERKs), which are involved in the induction of cell proliferation, are activated in the most aggressive type of glioma, i.e. glioblastoma multiforme (GBM). In fact, GBMs with increased levels of ERK activity exhibit a more aggressive phenotype than the others with moderate ERK activity, pointing to the importance of ERK and its kinase activity in the development and progression of these tumors. In this study, we have evaluated the effect of p38SJ, a novel member of the DING family of proteins, derived from Hypericum perforatum calluses, on the growth of malignant glioma cell lines, T98G and U-87MG by focusing on cell cycle and signaling pathways controlled by phosphorylation of various regulatory proteins including ERK. p38SJ, which exhibits profound phosphatase activity, shows the capacity to affect the phosphorylation status of several important kinases modulating signaling pathways, and cell growth and proliferation. Our results demonstrate that p38SJ reduces glioma cell viability and arrests cell cycle progression at G0/G1. The observed growth inhibitory effect of p38SJ is likely mediated by the downregulation of several cell cycle gatekeeper proteins, including cyclin E, Cdc2, and E2F-1. These results suggest that p38SJ may serve as a potential candidate for development of a therapeutic agent for the direct treatment of malignant gliomas and/or as a potential radiosensitizer.

Topics: Animals; CDC2 Protein Kinase; Cell Cycle Checkpoints; Cell Line, Transformed; Cell Line, Tumor; Cell Proliferation; Cyclin B; Cyclin E; Cyclin-Dependent Kinases; DNA-Binding Proteins; E2F Transcription Factors; Endopeptidase K; Extracellular Signal-Regulated MAP Kinases; Flow Cytometry; Gene Expression Regulation, Neoplastic; Glioblastoma; Green Fluorescent Proteins; Humans; Hypericum; Mice; Plant Preparations; Polycomb Repressive Complex 1; Tetrazolium Salts; Thiazoles; Time Factors; Transfection; Ubiquitin-Protein Ligases

Radiation induced optic neuropathy (RION) is a rare but severe consequence of radiation therapy that is associated with adjuvant chemotherapy, specifically therapy with vincristine or nitrosoureas. However, there is very little evidence regarding the occurrence of RION after concomitant radiochemotherapy with temozolomide.. The case of a 63 year old woman with glioblastoma multiforme and concomitant radiochemotherapy with temozolomide is described. Due to a slight depressive episode the patient also took hypericum perforatum. Five months after cessation of fractionated radiation and adjuvant chemotherapy with temozolomide (cumulative dose of 11040 mg) the patient developed bilateral amaurosis due to RION. Tumor regrowth was excluded by magnetic resonance imaging. After the application of gadolinium a pathognomonic contrast enhancement of both prechiasmatic optic nerves could be observed.. In this patient, the occurrence of RION may have been the result of radiosensitization by temozolomide, which could have been strengthened by hypericin. Consequently, physicians should avoid a concomitant application of hypericum perforatum and radiochemotherapy.

Topics: Antineoplastic Agents, Alkylating; Dacarbazine; Drug Therapy; Female; Glioblastoma; Humans; Hypericum; Magnetic Resonance Imaging; Middle Aged; Optic Nerve; Optic Nerve Diseases; Radiation; Radiation Injuries; Radiotherapy; Temozolomide