Level of brain-derived neurotrophic factor in the microenvironment of the neuron-astrocyte co-culture system by Mg2+-free-induced seizure-like discharge
WEN Xiang, JIANG Li, CHEN Heng-Sheng
Department of Neurology, Children's Hospital, Chongqing University of Medical Science, Chongqing 400014, China. dr_jiangli@hotmail.com
Abstract OBJECTIVE: To study the level of brain-derived neurotrophic factor (BDNF) in the microenvironment of the neuron-astrocyte co-culture system by Mg2+-free-induced seizure-like discharge and analyze the source of BDNF. METHODS: Hippocampal neurons (N) of fetal rats and astrocytes (AST) of neonatal rats were purified and divided into four groups, included control N (Con N) group, Mg2+-free treated N (Mg2+-free N) group, control N+AST co-culture (Con N+AST) group and Mg2+-free treated N+AST co-culture (Mg2+-free N+AST) group. The Mg2+-free treated groups were exposed to Mg2+-free media for 3 hrs to induce a repeated spontaneous seizure-like discharge. The level of BDNF in each group at different time points was measured using ELISA. RESULTS: The cellular morphous of AST changed in the Mg2+-free N+AST group at 48 hrs. Neuronal epileptiform activity was observed in the Mg2+-free media at 3 hrs, and continued to exist until the microenviornment returned to normal for 72 hrs. The BDNF level increased at 24 hrs and 48 hrs in the Con N+AST group compared with the control N group (P<0.05). Compared with Con N+AST group, BDNF level increased at 12, 24 and 48 hrs in the Mg2+-free N+AST group, especially at 12 and 24 hrs (P<0.01). There were no significant differences in the level of BDNF between the Con and Mg2+-free N groups. Compared with Mg2+-free N group, BDNF level increased at 24 hrs in the Mg2+-free N+AST group (P<0.05). CONCLUSIONS: The results of the experiment suggest that BDNF in the Con N+AST group might be excreted from both N and AST, but chiefly from N. Activated AST may be the main source for increasing BDNF in the Mg2+-free N+AST group.
WEN Xiang,JIANG Li,CHEN Heng-Sheng. Level of brain-derived neurotrophic factor in the microenvironment of the neuron-astrocyte co-culture system by Mg2+-free-induced seizure-like discharge[J]. 中国当代儿科杂志, 2012, 14(5): 375-379.
WEN Xiang,JIANG Li,CHEN Heng-Sheng. Level of brain-derived neurotrophic factor in the microenvironment of the neuron-astrocyte co-culture system by Mg2+-free-induced seizure-like discharge[J]. CJCP, 2012, 14(5): 375-379.
［3］Chen K, Henry RA, Hughes SM, Connor B. Creating a neurogenic environment: the role of BDNF and FGF2［J］. Mol Cell Neurosci, 2007, 36(1): 108-120.
［4］Paradiso B, Marconi P, Zucchini S, Berto E, Binaschi A, Bozac A, et al. Localized delivery of fibroblast growth factor-2 and brain-derived neurotrophic factor reduces spontaneous seizures in an epilepsy model［J］. Proc Natl Acad Sci, 2009, 106(17): 7191-7196.
［5］Bartkowska K, Turlejski K, Djavadian RL. Neurotrophins and their receptors in early development of the mammalian nervous system［J］. Acta Neurobiol Exp(Wars), 2010, 70(4): 454-467.
［6］Danzer SC, Crooks KR, Lo DC, McNamara JO. Increased expression of brain-derived neurotrophic factor induces formation of basal dendrites and axonal branching in dentate granule cells in hippocampal explant cultures［J］.J Neurosci, 2002, 22(22): 9754-9763.
［7］Sombati S, Delorenzo RJ. Recurrent spontaneous seizure activity in hippocampal neuronal networks in culture［J］.J Neurophysiol, 1995, 73(4): 1706-1711.
［8］Pitk-nen A, Sutula TP. Is epilepsy a progressive disorder? Prospects for new therapeutic approaches in temporal-lobe epilepsy［J］. Lancet Neurol, 2002, 1(3): 173-181.
［9］Poulsen FR, Jahnsen H, Blaabjerg M, Zimmer J. Pilocarpine-induced seizure-like activity with increased BNDF and neuropeptide Y expression in organotypic hippocampal slice cultures［J］. Brain Res, 2002, 950(1-2): 103-118.
［11］Tongiorgi E, Domenici L, Simonato M. What is the biological significance of BDNF mRNA targeting in the dendrites? Clues from epilepsy and cortical development［J］. Mol Neurobiol, 2006, 33(1): 17-32.
［12］Koyama R, Ikegaya Y. To BDNF or not to BDNF: that is the epileptic hippocampus［J］. Neuroscientist, 2005, 11(4): 282-287.
［13］Jessberger S, R-mer B, Babu H, Kempermann G. Seizures induce proliferation and dispersion of doublecortin-positive hippocampal progenitor cells［J］. Exp Neurol, 2005, 196(2): 342-351.
［14］Schr-der W, Hinterkeuser S, Seifert G, Schramm J, Jabs R, Wilkin GP, et al. Functional and molecular properties of human astrocytes in acute hippocampal slices obtained from patients with temporal lobe epilepsy［J］. Epilepsia, 2000, 41(Suppl 6): S181-S184.
［15］Alvarez-Maubecin V, Garcia-Hernandez F, Williams JT, Van Bockstaele EJ. Functional coupling between neurons and glia［J］.J Neurosci, 2000, 20(11): 4091-4098.
［16］Wilson JX. Antioxidant defense of the brain: a role for astrocytes［J］.Can J Physiol Pharmacol, 1997, 75(10-11): 1149-1163.
［17］Simonato M, Tongiorgi E, Kokaia M. Angels and demons: neurotrophic factors and epilepsy［J］. Trends Pharmacol Sci, 2006, 27(12): 631-638.
