This study aims to construct the recombinant lentivirus vector containing specific small interfering RNA (siRNA) targeting rat CREB binding protein(CBP)gene and to identify its function of inhibiting the expressions of acetylated histone in primarily cultured hippocampal neurons. Firstly, we constructed four kinds of recombinant lentivirus siCBP. And then we used them to infect the primarily cultured hippocampal neurons, and performed real-time PCR, western blot respectively to detect the expressions of CBP. Afterwards, the most effective lentivirus siCBP was used to infect the primarily cultured hippocampal neurons, and then the HAT activity and protein expressions of acetylated histone Ac-H3, Ac-H4 of the neurons were examined. By using PCR, endonuclease cutting and gene sequencing, we confirmed that the target genes were correctly cloned in lentivirus vector. Besides, CBP mRNA and protein expressions in neurons were found to be with varying degrees of decreases after infections of the four kinds of lentivirus siCBP. Furthermore, the representative and most effective lentivirus GR806 could effectively inhibit the HAT activity and the protein expressions of Ac-H3, Ac-H4 in neurons. It provides the experimental basis for the subsequent application of siCBP to clarify the effects and corresponding molecular mechanism of the CBP-dependent histone acetylation on learning and memory function in hippocampus.
ObjectiveTo preliminary study on the feasibility of constructing three-dimensional (3D) hippocampal neural network in vitro by using microfluidic technology.MethodsA network patterned microfluidic chip was designed and fabricated by standard wet etching process. The primary hippocampal neurons of neonatal Sprague Dawley rats were isolated and cultured, and then inoculated on microfluidic chip for culture. Immunofluorescence staining was used to observe the growth of hippocampal neurons at 3, 5, and 7 days of culture and electrophysiological detection of hippocampal neuron network at 7 days of culture.ResultsThe results showed that the number of hippocampal neurons increased gradually with the prolongation of culture time, and the neurite of neurons increased accordingly, and distributed uniformly and regularly in microfluidic chip channels, suggesting that the 3D hippocampal neuron network was successfully constructed in vitro. Single and multi-channel spontaneous firing signals of hippocampal neuronal networks could be detected at 7 days of culture, suggesting that neuronal networks had preliminary biological functions.ConclusionPatterned microfluidic chips can make hippocampal neurons grow along limited paths and form 3D neuron networks with corresponding biological functions such as signal transduction, which lays a foundation for further exploring the function of neuron networks in vitro.
Alzheimer’s disease (AD) is a chronic central neurodegenerative disease. The pathological features of AD are the extracellular deposition of senile plaques formed by amyloid-β oligomers (AβOs) and the intracellular accumulation of neurofibrillary tangles formed by hyperphosphorylated tau protein. In this paper, an in vitro pathological model of AD based on neuronal network chip and its real-time dynamic analysis were presented. The hippocampal neuronal network was cultured on the microelectrode array (MEA) chip and induced by AβOs as an AD model in vitro to simultaneously record two firing patterns from the interneurons and pyramidal neurons. The spatial firing patterns mapping and cross-correlation between channels were performed to validate the degeneration of neuronal network connectivity. This biosensor enabled the detection of the AβOs toxicity responses, and the identification of connectivity and interactions between neuronal networks, which can be a novel technique in the research of AD pathological model in vitro.