NASA Human Research Program Investigators' Workshop (2012)
4251.pdf
IMPACT OF SIMULATED MICROGRAVITY ON SURVIVAL, REPRODUCTION,
AND LIFESPAN OF CAENORHABDITIS ELEGANS
F. H. Abdel-Rahman, N. M. Alaniz, S. Heydari, E. Mansoor, and D. Sapp
Department of Biology, College of Science and Technology, Texas Southern University. 3100
Cleburne Ave., Houston, Texas 77004, (abdelrahman_fh@tsu.edu).
Model organisms have proven very useful in understanding the biological effects of the space
environment. Caenorhabditis elegans has several advantages for biological studies in space; it is
small, requiring little space; it is a self-fertilizing hermaphrodite, can live and reproduce in a
defined liquid or agar media. C. elegans in liquid cultures seeded with Escherichia coli OP50
were exposed to simulated microgravity using the NASA recommended High Aspect Ratio
Vessel (HARV) for different intervals, 3,6,9,and 12 days, and 4,8,12,and 16 days. Several
vials/and or flasks each containing 10 ml of C. elegans liquid cultures were maintained on a
shaker to serve as control. All treatments maintained at 21₀C. The initial populations of C.
elegans (all developmental stages) were determined prior to the exposure of the worms to
simulated microgravity (HARV), as well as those in the control. The final population for each
treatment (HARV exposed worms and control) were determined and all life stages were counted
when each treatment was terminated. The final population of all life stages of the HARV
exposed C. elegans was lower than the control in all treatments. Extracted eggs from cultures
exposed to simulated microgravity took longer time to develop to the first larval stage and to
hatch, the longer the exposure. Microscopic examination of adult stages of the progeny of the
exposed C. elegans to simulated microgravity exhibited a congested digestive system with
unprocessed E. coli. The molecular probe DAPI and the fluorescent microscope are used to
determine the effect of simulated microgravity on the germinal cells count in the ovaries of C.
elegans adult hermaphrodite.