In June 2011, our multidisciplinary team of six undergraduate Boise State students will perform an experiment at Johnson Space Center aboard NASA's reduced gravity aircraft: we aim correlate the effects of gravitational acceleration to calcium ion concentration in live bone cell culture. Ultimately, the study serves as a preliminary data source to guide future work in the area of preventative bone loss treatment.
-- Abstract: Bone homeostasis is a dynamic phenomena in which environmental stress information is continually translated into remodeling responses by specialized sensory and effector cell populations. Under normal conditions this remodeling process promotes optimal distribution of mineralized matrix to meet biomechanical requirements. Under extreme conditions the remodeling balance can shift toward excessive resorption or mineralization, as evidenced by prolonged exposure to microgravity leading to bone loss in astronauts. In order to prevent and treat bone pathologies resulting from imbalanced remodeling it is crucial to identify the regulatory mechanisms that allow sensory cells to integrate varied and often contrasting mechanical stimuli into committed effector responses. A current model proposes that the biochemical pathways orchestrating remodeling act in simple opposition to opposing stimuli, however evidence exists that suggests a capacity for more complex regulative behavior. Parabolic flight provides an ideal environment to examine the intersection of opposing stimuli in the form of hyper and microgravity. Co-cultures of sensor (osteocyte) and effector (osteoblast) cells will be exposed to oscillating gravitational conditions and the activity of calcium, an early mediator of mechanosensitive responses, will be monitored. If calcium responses are shown to vary over the course of cycles between hyper and microgravity rather than to respond in simple and consistent opposition, mechanisms related to calcium flux will be implicated as potential points of regulation.
Below is a five minute project overview presented at the Egyptian Theatre in Boise, Idaho.