Bacoside A Induced Sub-G0 Arrest and Early Apoptosis in Human Glioblastoma Cell Line U-87 MG through Notch Signaling Pathway

BACKGROUND: Glioblastoma multiforme (GBM) is a highly malignant brain tumor with a worst prognosis of less than one year despite advance treatment facilities. Among various signaling pathway genes displaying genetic modifications, aberrant expression of Notch pathway genes is frequent in GBM offering novel therapeutic targets. Herbal extracts having anticancer properties are used in adjuvant therapy that is safe and affordable as compared to chemotherapeutics. Bacopa monnieri has been used for the development of brain cells because of its neuroprotective properties. Its anticancer properties have shown to be promising in cancer treatment. METHODS: The anticancer properties of Bacoside A, an active and abundant component of Bacopa monnieri was assessed on U-87 MG cell line and its effects on expression of Notch pathway genes were studied. Cell cycle arrest and apoptosis were studied using flow cytometry. Expression of Notch pathway genes comprising of Notch receptors (notch1, notch2, notch3 and notch4), ligands (jagged1 and jagged2), a component of gamma-secretase complex (APH1A) and downstream target (HES1) were evaluated by quantitative real-time PCR. RESULTS: Bacoside A exhibited considerable cytotoxicity on U-87 MG cells inducing cell cycle arrest and apoptosis. Cell cycle analysis revealed a significant arrest of 39.21% cells in sub-G0 phase at 80 µg/mL concentration, increasing to 53.21% at a higher concentration of 100 µg/mL. The fraction of early apoptotic cells in control was low (3.48%) that increased substantially to 31.36% and 41.11% after 80 µg/mL and 100 µg/mL of Bacoside A treatment respectively. Additionally, the expression of notch1 gene decreased after exposure to Bacoside A with a fold change of 0.05, whereas HES1 gene expression was increased by 25 fold. CONCLUSION: These data indicate that Bacoside A has a possible anticancer activity that could be inducing cell cycle arrest and apoptosis through Notch pathway in GBM in vitro.

Studies on Behavioral, Biochemical, Immunohistochemical and Quantification of Dopamine and its Metabolites in the Striatum of 6-Hydroxy Dopamine Induced Parkinsonism in Rats - Attenuation by Bacosidea-A, A Major Phytoconstituent of Bacopa Monniera.

Bacoside-A, a major constituent isolated from Bacopa monniera is held in high repute as a potent nerve tonic. Rats were pretreated with Bacoside - A (10mg/kg and 20mg/kg body weight) for 21 days. A Parkinsonian model in rats was developed by giving 6-hydroxy dopamine (12μg/2μl in 0.1% ascorbic acid- saline) in the right striatum on 22nd day. A significant protection on lipid peroxidation, glutathione, glutathione peroxidase, glutathione reductase, superoxide dismutase and catalase was observed in the striatum of lesioned group animals pretreated with 10 mg/kg body weight of Bacoside-A for 21 days as compared to lesion group animals. We tested the behavioral response at different time points after injection of 6-hydroxy dopamine to evaluate the onset and progression of behavioral abnormalities. Also quantification of dopamine and its metabolites, DOPAC and HVA was done using HPLC coupled with electrochemical detector. The results showed a reduction in the levels of dopamine and its metabolites, increase in the locomotor activity, increase in "depression"-like behavior and a marked change in the social behavior in the 6 - hydroxy dopamine induced group whereas learning and memory abilities were not affected. Finally, all of these results were exhibited by an increase in the density of TH-IR fibers in the ipsilateral substantia nigra of the lesioned group following treatment with Bacoside- A. This study indicates that Bacoside-A, an active compound from Bacopa monniera, is helpful in attenuating the changes caused by 6-hydroxy dopamine induced lesions and has therapeutic potential in fighting against Parkinson's disease.