C6 Glioma Research Articles

Brain extracellular matrix attenuates photodynamic cytotoxicity of glioma cells

Glioma is the most common tumor in the central nervous system, which is often accompanied by poor prognosis. Brain extracellular matrix (ECM) plays an important role in regulating the growth and migration of glioma. Photodynamic therapy (PDT) has been an effective method for the treatment of solid tumors by oxidative modifications in recent years, and ECM may have an impact on the cytotoxicity of photodynamic therapy. In this work, we prepared decellularized brain ECM by chemical method to investigate the influence of the photodynamic effect of glioma C6 cells. Compared with decellularized liver ECM, brain ECM reduces PDT cytotoxicity. By observing the content of reactive oxygen species produced by near-infrared light active indocyanine green in cells, it was found that ECM did not affect the production of reactive oxygen species. Therefore, it is speculated that brain ECM may enhance the oxidative stress adaptability of glioma cells through potential signal regulation, or protect photodynamic targeting biomolecules (such as proteins and other cellular components) from oxidation in PDT mediated by indocyanine green and 808 nm laser in glioma cells.

Antitumor activity of irinotecan with ellagic acid in C6 glioma cells.

SUMMARYOBJECTIVE:Irinotecan-based combination chemotherapies in malignant gliomas need to be examined. The aim of this study was to investigate the synergetic effect of ellagic acid, a natural polyphenolic antioxidant compound, with irinotecan, an inhibitor of topoisomerase I enzyme, on the growth, cadherin switch, and angiogenic processes of a glioma cell line.METHODS:A combination of 100 μM ellagic acid and 100 μM irinotecan was applied to rat C6 glioma cells for 24th, 48th, and 72nd h. The cell proliferation was evaluated by 5-bromo-2′-deoxyuridine immunocytochemistry. The expression levels of vascular endothelial growth factor, E-cadherin, and N-cadherin were measured using real-time polymerase chain reaction and their immunoreactivities using immunocytochemistry.RESULTS:The treatment of irinotecan with combining ellagic acid enhanced antitumor activity and the synergistic effect of these reduced the cell proliferation of C6 glioma by inhibiting the cadherin switch and promoting the antiangiogenic processes.CONCLUSIONS:Further research is required to prove a negative relationship between C6 glial cell proliferation and irinotecan with ellagic acid application. Our preliminary data suggest that even with the extremely short-term application, irinotecan with ellagic acid may affect glioma cells at the level of gene and protein expression.

Investigation of the Anticancer Effect of S-Allyl-L Cysteine on the C6 Rat Glioma Cell Line in vitro in 2D- and 3D-Cell Culture Models.

In our study, we aimed to investigate the effects of SAC on C6 glioblastoma cells and its antiproliferative and apoptotic effects on two- and three-dimensional cell culture systems. The rat glioma cell line C6 was separated into 2D-Control, 2D-SAC, 3D-CMC-Control and 3D-CMC-SAC groups. While control cells were incubated under standard culture conditions, cells in the SAC groups were incubated with the IC50 dose (50 µM for both the 2D-SAC C6 and 3D-CMC-SAC groups) of SAC in culture medium for 24 and 48 hours. Thereafter, all groups were stained with antibodies recognizing NOTCH1 and JAGGED1, and the mRNA expression levels of NOTCH1 and JAGGED1 were evaluated by qRT-PCR. Increasing doses of SAC were administered for 24 hours in the C6 glioma cell line. The concentration of 50 μM was chosen as the most suitable dose for administration. The gene expression profiles were different in the two forms of culture. NOTCH1 receptor mRNA expression levels were significantly decreased in cells treated with 50 μM SAC for 24 hours compared to control cells in both the two-dimensional (2D) and three-dimensional (3D) cell cultures. The immunoreactivities of both of these markers (JAGGED1 and NOTCH1) were significantly decreased in the glioma cells in the SAC group compared to the control group. This study shows that SAC has potential as a drug for human use, as indicated by its nontoxic nature. The present study confirmed the anticancer activity of SAC by modulating NOTCH1 and JAGGED1 signaling in glioma cancer cells.

Erratum to "Carbon Monoxide Ameliorates 6-Hydroxydopamine-Induced Cell Death in C6 Glioma Cells" [Biomol. Ther. 26 (2018) 175-181

The Fig. 4A has been accidentally duplicated in Fig. 5A during publication processes. The authors request to correct the Fig. 5A of page 179, replacing the duplicated wrong figure with the original right one.

Identification of novel quinazolinone hybrids as cytotoxic agents against C6 glioma cell lines

AbstractNovel quinazolinone‐triazole hybrid heterocycles were identified as cytotoxic agents to inhibit glioblastoma cell proliferation. These compounds were synthesized using click reaction by building a triazole linker on quinazolinone and tested for cytotoxicity on C6 glioma cell lines, a facsimile of glioblastoma multiforme. Few of these series significantly reduced the proliferation of cell lines with IC50 8–15 μM and may act as fetching leads for glioblastoma therapies. The binding affinity and ligand‐receptor interaction between hybrids and rat thymidylate synthase were investigated using molecular docking techniques.

A three-dimensional electrochemical biosensor integrated with hydrogel for cells culture and lactate release monitoring

Three-dimensional (3D) cell culture has attracted increasing interest in many fields with the significant advantages in reproducing in vivo cell environment. For the characterization of biochemical information, electrochemical sensing has stood out from other techniques in real-time monitoring of living cells, and made an attempt to integrate with hydrogel for investigating the biological processes in 3D cell culture. However, it is still a challenge for real-time monitoring of cellular metabolites therein for the lack of electrochemical activity, and lactate (the product of aerobic glycolysis) is a typical example of such a predicament. Herein, we developed a 3D enzymatic electrochemical sensor that could be integrated with collagen hydrogel to monitor the lactate levels of cells cultured therein. Specifically, lactate oxidase immobilized on the outer surface of 3D sensor could oxidize lactate with H2O2 as a product, and Prussian blue nanoparticles electrodeposited on carbon nanotubes adsorbed electrode conferred the excellent and stable electrocatalytic performance to H2O2 for lactate detection. Further, the 3D sensor was integrated with collagen hydrogel with C6 glioma cells seeded therein and allowed the successful real-time monitoring of lactate released from C6 glioma cells, providing an effective detection platform for exploring the biochemical response in 3D cell culture systems.

AMPK Modulates the Metabolic Adaptation of C6 Glioma Cells in Glucose-Deprived Conditions without Affecting Glutamate Transport.

Energy homeostasis in the central nervous system largely depends on astrocytes, which provide metabolic support and protection to neurons. Astrocytes also ensure the clearance of extracellular glutamate through high-affinity transporters, which indirectly consume ATP. Considering the role of the AMP-activated protein kinase (AMPK) in the control of cell metabolism, we have examined its implication in the adaptation of astrocyte functions in response to a metabolic stress triggered by glucose deprivation. We genetically modified the astrocyte-like C6 cell line to silence AMPK activity by overexpressing a dominant negative mutant of its catalytic subunit. Upon glucose deprivation, we found that C6 cells maintain stable ATP levels and glutamate uptake capacity, highlighting their resilience during metabolic stress. In the same conditions, cells with silenced AMPK activity showed a reduction in motility, metabolic activity, and ATP levels, indicating that their adaptation to stress is compromised. The rate of ATP production remained, however, unchanged by AMPK silencing, suggesting that AMPK mostly influences energy consumption during stress conditions in these cells. Neither AMPK modulation nor prolonged glucose deprivation impaired glutamate uptake. Together, these results indicate that AMPK contributes to the adaptation of astrocyte metabolism triggered by metabolic stress, but not to the regulation of glutamate transport.

Targeted gene delivery to the brain using CDX-modified chitosan nanoparticles.

Introduction: Blood-brain barrier with strictly controlled activity participates in a coordinated transfer of bioactive molecules from the blood to the brain. Among different delivery approaches, gene delivery is touted as a promising strategy for the treatment of several nervous system disorders. The transfer of exogenous genetic elements is limited by the paucity of suitable carriers. As a correlate, designing high-efficiency biocarriers for gene delivery is challenging. This study aimed to deliver pEGFP-N1 plasmid into the brain parenchyma using CDX-modified chitosan (CS) nanoparticles (NPs). Methods: Herein, we attached CDX, a 16 amino acids peptide, to the CS polymer using bifunctional polyethylene glycol (PEG) formulated with sodium tripolyphosphate (TPP), by ionic gelation method. Developed NPs and their nanocomplexes with pEGFP-N1 (CS-PEG-CDX/pEGFP) were characterized using DLS, NMR, FTIR, and TEM analyses. For in vitro assays, a rat C6 glioma cell line was used for cell internalization efficiency. The biodistribution and brain localization of nanocomplexes were studied in a mouse model after intraperitoneal injection using in vivo imaging and fluorescent microscopy. Results: Our results showed that CS-PEG-CDX/pEGFP NPs were uptaken by glioma cells in a dose-dependent manner. In vivo imaging revealed successful entry into the brain parenchyma indicated with the expression of green fluorescent protein (GFP) as a reporter protein. However, the biodistribution of developed NPs was also evident in other organs especially the spleen, liver, heart, and kidneys. Conclusion: Based on our results, CS-PEG-CDX NPs can provide a safe and effective nanocarrier for brain gene delivery into the central nervous system (CNS).

Chemical Exchange Saturation Transfer (CEST) Signal at -1.6 ppm and Its Application for Imaging a C6 Glioma Model.

The chemical exchange saturation transfer (CEST) signal at −1.6 ppm is attributed to the choline methyl on phosphatidylcholines and results from the relayed nuclear Overhauser effect (rNOE), that is, rNOE(−1.6). The formation of rNOE(−1.6) involving the cholesterol hydroxyl is shown in liposome models. We aimed to confirm the correlation between cholesterol content and rNOE(−1.6) in cell cultures, tissues, and animals. C57BL/6 mice (N = 9) bearing the C6 glioma tumor were imaged in a 7 T MRI scanner, and their rNOE(−1.6) images were cross-validated through cholesterol staining with filipin. Cholesterol quantification was obtained using an 18.8-T NMR spectrometer from the lipid extracts of the brain tissues from another group of mice (N = 3). The cholesterol content in the cultured cells was manipulated using methyl-β-cyclodextrin and a complex of cholesterol and methyl-β-cyclodextrin. The rNOE(−1.6) of the cell homogenates and their cholesterol levels were measured using a 9.4-T NMR spectrometer. The rNOE(−1.6) signal is hypointense in the C6 tumors of mice, which matches the filipin staining results, suggesting that their tumor region is cholesterol deficient. The tissue extracts also indicate less cholesterol and phosphatidylcholine contents in tumors than in normal brain tissues. The amplitude of rNOE(−1.6) is positively correlated with the cholesterol concentration in the cholesterol-manipulated cell cultures. Our results indicate that the cholesterol dependence of rNOE(−1.6) occurs in cell cultures and solid tumors of C6 glioma. Furthermore, when the concentration of phosphatidylcholine is carefully considered, rNOE(−1.6) can be developed as a cholesterol-weighted imaging technique.

Terpenoids from Glechoma hederacea var. longituba and their biological activities.

Glechoma hederacea var. longituba (common name: ground ivy) has been used for the treatment of asthma, bronchitis, cholelithiasis, colds, and inflammation. In the present study, three new sesquiterpene glycosides (1–3), two new diterpene glycosides (4 and 5), and four known compounds (6–9) were isolated from its MeOH extract. A structure elucidation was performed for the five new compounds (1–5) using 1D and 2D NMR, HRESIMS, DP4+ and ECD calculations, and chemical methods. All the isolates (1–9) were assessed for their antineuroinflammatory activities on nitric oxide (NO) production in lipopolysaccharide (LPS)-activated BV-2 cells, nerve growth factor (NGF) secretion stimulation activities in C6 glioma cells, and cytotoxic activities against four human cancer cell lines (A549, SK-OV-3, SK-MEL-2, and HCT15). Compounds 2 and 5–7 exhibited inhibitory effects on the NO production with IC50 values of 52.21, 47.90, 61.61, and 25.35 μM, respectively. Compound 5 also exhibited a significant stimulating effect on NGF secretion (122.77 ± 8.10%). Compound 9 showed potent cytotoxic activity against SK-OV-3 (IC50 = 3.76 μM) and SK-MEL-2 (IC50 = 1.48 μM) cell lines, while 7 displayed a strong cytotoxic activity against the SK-MEL-2 (IC50 = 9.81 μM) cell line.

Integration of synthetic and natural derivatives revives the therapeutic potential of temozolomide against glioma- an in vitro and in vivo perspective

AimsMalignant gliomas constitute one of the deadly brain tumors with high degeneration rate. Though temozolomide (TMZ) is the first-line drug for glioma, its efficacy has decreased due to chemo-resistance. Repurposing synthetic and natural compounds have gained increasing interest in glioma. Hence, we combined chloroquine (CHL) a synthetic drug, naringenin (NAR) and phloroglucinol (PGL) (natural derivatives), to investigate whether the apoptotic effect of these drugs both alone and in combination, enhances the anti-tumor effects of TMZ in an in vitro and in vivo orthotopic xenograft glioma model. Main methodsThe cytotoxic effect of the drugs was assessed in C6 (murine) glioma cells, U-87 MG and LN229 (human) glioblastoma cells, primary astrocytes (isolated from rat brain tissues) and HEK-293 T cells. Mitochondrial depolarization and alterations in the cell cycle was determined by confocal imaging and flow cytometry. The expression of angiogenic and apoptotic markers was evaluated using qRT-PCR and ELISA. The efficacy of the combinatorial treatment was assessed in an orthotopic xenograft model using U-87 MG cells. Key findingsThe combinatorial treatment inhibited cell proliferation, induced apoptosis and contributed to cell cycle arrest in glioma cells. The quadruple combinatorial cocktail down-regulated BCL-2 with a concomitant decrease in VEGF. As observed in vitro, the quadruple combinatorial treatment enhanced the median survival of glioma-induced rats with lower cellularity rate. SignificanceThe combination of CHL, NAR and PGL synergistically potentiated the efficacy of TMZ on glioma in vitro and in vivo. Hence, this combination may characterize an advanced strategy for glioma treatment, thereby providing a possible translation to clinical trial.

Rat and Mouse Brain Tumor Models for Experimental Neuro-Oncology Research.

Rodent brain tumor models have been useful for developing effective therapies for glioblastomas (GBMs). In this review, we first discuss the 3 most commonly used rat brain tumor models, the C6, 9L, and F98 gliomas, which are all induced by repeated injections of nitrosourea to adult rats. The C6 glioma arose in an outbred Wistar rat and its potential to evoke an alloimmune response is a serious limitation. The 9L gliosarcoma arose in a Fischer rat and is strongly immunogenic, which must be taken into consideration when using it for therapy studies. The F98 glioma may be the best of the 3 but it does not fully recapitulate human GBMs because it is weakly immunogenic. Next, we discuss a number of mouse models. The first are human patient-derived xenograft gliomas in immunodeficient mice. These have failed to reproduce the tumor-host interactions and microenvironment of human GBMs. Genetically engineered mouse models recapitulate the molecular alterations of GBMs in an immunocompetent environment and “humanized” mouse models repopulate with human immune cells. While the latter are rarely isogenic, expensive to produce, and challenging to use, they represent an important advance. The advantages and limitations of each of these brain tumor models are discussed. This information will assist investigators in selecting the most appropriate model for the specific focus of their research.

Glioma facilitates the epileptic and tumor-suppressive gene expressions in the surrounding region

Patients with glioma often demonstrate epilepsy. We previously found burst discharges in the peritumoral area in patients with malignant brain tumors during biopsy. Therefore, we hypothesized that the peritumoral area may possess an epileptic focus and that biological alterations in the peritumoral area may cause epileptic symptoms in patients with glioma. To test our hypothesis, we developed a rat model of glioma and characterized it at the cellular and molecular levels. We first labeled rat C6 glioma cells with tdTomato, a red fluorescent protein (C6-tdTomato), and implanted them into the somatosensory cortex of VGAT-Venus rats, which specifically expressed Venus, a yellow fluorescent protein in GABAergic neurons. We observed that the density of GABAergic neurons was significantly decreased in the peritumoral area of rats with glioma compared with the contralateral healthy side. By using a combination technique of laser capture microdissection and RNA sequencing (LCM-seq) of paraformaldehyde-fixed brain sections, we demonstrated that 19 genes were differentially expressed in the peritumoral area and that five of them were associated with epilepsy and neurodevelopmental disorders. In addition, the canonical pathways actively altered in the peritumoral area were predicted to cause a reduction in GABAergic neurons. These results suggest that biological alterations in the peritumoral area may be a cause of glioma-related epilepsy.

Effects of Taheri Consciousness Fields on the Rat C6 Glioma Cell Line

The most common primary spinal cord and brain tumors are gliomas, representing 81% of malignant brain tumors. In neuro-oncology investigations, the rat C6 glioma cell line has mostly been utilized as an experimental model system. Taheri Consciousness Fields (TCFs) founded and introduced by Mohammad Ali Taheri, are novel fields that are neither matter nor energy. Therefore, they are non-quantifiable and cannot be directly observed or measured. However, it is possible to demonstrate and measure the effects of these fields through standard scientific experiments. This study aimed to evaluate the effect of TCFs (A and B) on the C6 glioma cell line in three and four treatments compared with the control (nono-treatment) group. To study morphology and microscopic properties of the cells, cells were detached and stained with trypan blue then the dead cells were counted. An MTT assay was used in order to evaluate the effect of TCFs. The expression of Bax and Bcl-2 genes was assessed by using the RT Real-time PCR. The results showed that the TCFs treatment not only reduced the number of the C6 glioma cells but also changed their morphology. Similarly, in the trypan blue dye count, more dead cells were counted in the TCFs groups in comparison to the control group. In the MTT assay, both TCFs displayed a cytotoxic effect in incubation times on the C6 glioma cells (p< 0.05). Bax/Bcl2 ratio increased to 3.5 and 7-fold, compared to the control via TCF (A), and (B), respectively (P<0.05). The findings suggest that TCF (A) and (B) can induce apoptosis in the rat C6 glioma cells. The TCF (B) effect was greater than the effect of TCF (A) in all tests. The mechanism of action of TCFs is still not definable by researchers, and it can be useful to elucidate the effects of the TCFs treatment in vivo and in clinical research.

Evaluation of Temozolomide Treatment for Glioblastoma Using Amide Proton Transfer Imaging and Diffusion MRI.

Simple SummaryGlioblastoma (GBM), the most frequent and malignant histological type of glioma, is associated with a very high mortality rate. MRI is a useful method for the evaluation of tumor growth. However, there are few studies that have quantitatively evaluated the changes in disease state after TMZ treatment against GBM, and it is not fully understood how the effects of treatment are reflected in the quantitative values measured on MRI. We used the C6 glioma rat model to evaluate the tumor changes due to chemotherapy at different doses of TMZ in terms of quantitative values measured by neurite orientation dispersion and density imaging (NODDI) and amide proton transfer (APT) imaging using 7T-MRI. These methods can evaluate the microstructural changes caused by TMZ-induced tumor growth inhibition.This study aimed to evaluate tumor changes due to chemotherapy with temozolomide (TMZ) in terms of quantitative values measured by APT imaging and NODDI. We performed TMZ treatment (administered orally by gavage to the TMZ-40 mg and TMZ-60 mg groups) on 7-week-old male Wistar rats with rat glioma C6 implanted in the right brain. T2WI, APT imaging, diffusion tensor imaging (DTI), and NODDI were performed on days 7 and 14 after implantation using 7T-MRI, and the calculated quantitative values were statistically compared. Then, HE staining was performed on brain tissue at day 7 and day 14 for each group to compare the results with the MR images. TMZ treatment inhibited tumor growth and necrotic area formation. The necrotic areas observed upon hematoxylin and eosin (HE) staining were consistent with the MTR low-signal areas observed upon APT imaging. The intracellular volume fraction (ICVF) map of the NODDI could best show the microstructure of the tumor, and its value could significantly highlight the difference in treatment effects at different TMZ doses. APT imaging and NODDI can be used to detect the microstructural changes caused by TMZ-induced tumor growth inhibition. The ICVF may be useful as a parameter for determining the effect of TMZ.

Influence of 3-acetyl-5-hydroxy-2-methylindole on glioma cell proliferation and metabolism

A 3-acetyl analogue of 5-hydroxyindole was synthesised and evaluated for its effects on rat C6 glioma cell functions. It was found that 3-acetyl-5-hydroxy-2-methylindole at 10 μmol/L led to a sharp reduction of mitochondrial membrane potential, induction of autophagy and decrease of proliferation of C6 glioma cells. The compound’s effect was comparable to that of rotenone, an inhibitor of cell respiration.

Sugammadex Causes C6 Glial Cell Death and Exacerbates Hydrogen Peroxide-induced Oxidative Stress

Objective: Sugammadex (SUG) quickly reverses steroidal neuromuscular blocking drugs after anesthesia. It has been reported that SUG has a toxic effect on neurons in primary culture. This study aims to examine the effect of SUG on glial cell viability, oxidative stress, and apoptosis in C6 glial cells after exposure to H2O2. Method: In this study, C6 glioma cell line was used to study the effect of SUG on the glial cell in four cell groups. The control group was untreated. Cells in the H2O2group were treated with 0.5 mM H2O2 for 24 h. Cells in the SUG group were treated with 50 μg/mL SUG for 24 h. Cells in the SUG+ H2O2 group were pre-treated with 50 μg/mL of SUG for 1 h before 24-h exposure to 0.5 mM H2O2. Cell viability was evaluated using XTT assay. Total antioxidant status (TAS), total oxidant status (TOS), caspase-3, Bax, 8-hydroxy-2′ -deoxyguanosine (8-OHdG), and cleaved-PARP levels in the cells were measured by commercial kits. Results: SUG significantly decreased the viability of C6 cells after H2O2-induced oxidative stress (p < 0.05). SUG pretreatment also raised TOS levels and led to increased Bax, Caspase-3, 8-OHdG, and cleaved PARP levels after H2O2-induced oxidative damage in C6 cells (p < 0.05).

A quinoline-based probe for the ratiometric fluorescent detection of sulfite in lysosomes of living cells

A lysosome-targeting ratiometric fluorescent probe was synthesized for detecting sulfite based on sulfite-triggered nucleophilic addition reaction. Due to the specific reaction, the fluorescence intensity ratio (I530/I390) of the probe in an almost aqueous solution (0.5% DMSO) changed significantly after the addition of HSO3−, corresponding to the change in the fluorescence color of the solution from green to blue. The recognition was conducted using high-resolution mass spectrometry, proton nuclear magnetic resonance, and density functional theory calculations. The fluorescent probe could be utilized to quantitatively monitor HSO3− in lysosomes of living C6 glioma cells and real-water samples.

Captopril exhibits protective effects through anti-inflammatory and anti-apoptotic pathways against hydrogen peroxide-induced oxidative stress in C6 glioma cells.

Recent studies have shown that angiotensin-converting enzyme (ACE) inhibitors have reduced oxidative damage in the central nervous system (CNS). Accumulating evidence have also demonstrated that captopril, an ACE inhibitor, has protective effects on the CNS. However, its effects on hydrogen peroxide (H2O2)-induced oxidative damage in glial cells and interaction with the inflammatory system are still uncertain. Therefore, this study was aimed to investigate the protective effect of captopril on glial cell damage after H2O2-induced oxidative stress involved in the inflammatory and apoptotic pathways. The control group was without any treatment, and the H2O2 group was treated with 0.5mM H2O2 for 24h. The captopril group was treated with various concentrations of captopril for 24h. The captopril + H2O2 group was pre-treated with captopril for 1h and then exposed to 0.5mM H2O2 for 24h. In the captopril + H2O2 group, captopril at all concentrations significantly increased the cell viability in C6 cells. It also significantly increased the TAS and decreased the TOS levels which are an indicator of oxidative stress. Moreover, captopril significantly reduced the inflammation markers including NF-kB, IL-1 β, COX-1, and COX-2 levels. Flow cytometry results also exhibited that captopril pretreatment significantly decreased the apoptosis rate. Besides, captopril significantly reduced apoptotic Bax and raised anti-apoptotic Bcl-2 protein levels. In conclusion, captopril has protective effects on C6 cells after H2O2-induced oxidative damage by inhibiting oxidative stress, inflammation, and apoptosis. However, further studies need to be conducted to evaluate the potential of captopril as a neuroprotective agent.

Procyanidins and Phlobatannins from the Twigs of Rosa multiflora and Their Neuroprotective Activity.

Three new procyanidins (1-3), two new phlobatannins (6 and 7), a new flavan-3,4-diol glycoside (9), and a new neolignan glycoside (10), along with three previously reported compounds (4, 5, and 8) were isolated from the twigs of Rosa multiflora. The chemical structures of the new compounds (1-3, 6, 7, 9, and 10) were characterized by spectroscopic data interpretation, including NMR (1H and 13C NMR, 1H-1H COSY, HSQC, HMBC, and NOESY) and HRESIMS analysis. Experimental ECD data analysis was conducted to assign the absolute configurations of the new compounds (1-3, 6, 7, 9, and 10). The absolute configuration of the sugar moieties was verified through a chiral derivatization method and LC-MS analysis. All the isolated compounds (1-10) were evaluated for their anti-neuroinflammatory activity based on inhibitory effects on nitric oxide production using a lipopolysaccharide-stimulated murine microglia BV-2 cell line and for their neurotrophic effects on nerve growth factor induction in C6 glioma.