Student: Shahzadi Aimen
Project Mentors: Dr. Jitendran Muthuswamy – SBHSE
Dr. Arati Sridharan – SBHSE
Dr. James Abbas – SBHSE
YouTube Link: View the video link below before joining the zoom meeting
Zoom link: https://asu.zoom.us/j/95446038115
Zoom meeting time: 9am – 11am
Abstract
Many studies have shown that calcium (Ca2+) is necessary for neurotransmitter release modulation, synaptic transmission and activity, as well as in transmitting signal for depolarization in neurons. Calcium (Ca2+) influx have also been witnessed as a result of mechanical trauma due to electrode implantation in the brain. There is also evidence of mechanoporation and mechanical distortion in neurons as a result of calcium (Ca2+) influx after electrode implantation. However, these studies involve invasive approach for understanding role of calcium (Ca2+) due to mechanical transduction. The aim of this study is to analyze intracellular calcium (Ca2+) response to low-intensity pulsed ultrasound (LIPUS) stimulation in primary cortical neuronal cultures. Low-intensity ultrasound has been shown to result in expression of neurotrophic factor in glial cells via Calcium-CaMK signaling pathway activation. However, calcium (Ca2+) influx due to low-intensity ultrasound stimulation mediated by transient mechanical modifications in neurons is not well studied. Preliminary in vitro experiments using potassium chloride (KCl) for stimulation of primary cortical neurons were conducted and real-time calcium dynamics was captured with confocal imaging tool. Fluo-4 (calcium indicator) was used for the initial experiments and mean intensity of fluorescence was acquired using FIJI/ImageJ. Further analysis of preliminary data was carried out by calculating dF/F = (F – F0)/ F0 and plotting it against time, where F is fluorescence value and F0 is median of fluorescence (F) distribution. The results of preliminary experiments will be analyzed against the results obtained from low-intensity pulsed ultrasound stimulation of in vitro samples for calcium (Ca2+) release. The cells will be excited using 490 nm of blue light illumination and images will be acquired for 60 seconds with 1 frame per second speed. LIPUS will be applied at frame 20 for 10 seconds. The input waveform for LIPUS will contain 3 MHz frequency and Vpp of 800 mV, and it will be repeated every 1 sec for 10 secs. Neuronal cell cultures provide a convenient model to assess Ca2+ dynamics in neurons in response to LIPUS.