Neonatal rat heart cells cultured in simulated microgravity

Abstract

JSUMMARYIn vitro characteristics of cardiac cells cultured in simulated microgravity are reported.o Tissue culture methods performed at unit gravity constrain cells to propagate, differentiate, and interact in a two dimensional (2D) plane. Neonatal rat cardiac cells in 2D culture organize predominantly as bundles of cardiomyocytes with the intervening areas filled by non-myocyte cell types. Such cardiac cell cultures respond predictably to the addition of exogenous compounds, and in many ways they represent an excellent in vitro model system. The gravity-induced 2D organization of the cells, however, does not accurately reflect the distribution of cells in the intact tissue. We have begun characterizations of a three-dimensional (3D) culturing system designed to mimic microgravity. The NASA designed High-Aspect-Ratio-Vessel (HARV) bioreactors provide a low shear environment which allows cells to be cultured in static suspension. HARV-3D cultures were prepared on microcarrier beads and compared to control-2D cultures using a combination of microscopic and biochemical techniques. Both systems were uniformly inoculated and medium exchanged at standard intervals. Cells in control cultures adhered to the polystyrene surface of the tissue culture dishes and exhibited typical 2D organization. Cells in cultured in HARVs adhered to microcarrier beads, the beads aggregated into defined clusters containing 8 to 15 beads per cluster, and the clusters exhibited distinct 3D layers: myocytes and fibroblasts appeared attached to the surfaces of beads and were overlaid by an outer cell type. In addition, cultures prepared in HARVs using alternative support matrices also displayed morphological formations not seen in control cultures. Generally, the cells prepared in HARV and control cultures were similar, however, the dramatic alterations in 3D organization recommend the HARV as an ideal vessel for the generation of tissue-like organizations of cardiac cells in simulated microgravity.

Proteomics and genomics of microgravity

“…Researchers have also been investigating the effects of microgravity on cardiac muscle (1,86). Decreases in contractile force and velocity, as well as, Ca 2ϩ -dependent actomyosin ATPase activity were seen in cardiac cells of tail suspension rats (120).…”

Skeletal muscle satellite cells cultured in simulated microgravity

“…Removing the restriction of satellite cell growth and differentiation in two-dimensions could result in muscle tissue that more closely resembles their in vivo counterpart and thus provide a better model to study muscle atrophy and regeneration. Description of the HARV bioreactor and conditions provided by it are detailed in a companion manuscript (1). In this study we use the HARV bioreactor to facilitate growth and ' > o°.…”

Formation of three‐dimensional fetal myocardial tissue cultures from rat for long‐term cultivation

“…This fact may explain why, even after longterm cultivation of up to 8 months, a functional loss of autonomous beating did not occur. On the other hand, this increases technical demands with respect to tissue acquisition in comparison to the widely used neonatal rats (Akins et al, 1997;Bursac et al, 2002;Shimizu et al, 2002;Zimmermann et al, 2004;Baar et al, 2005).…”