Lipid Profile, Cortisol and Haematological Alterations in Simulated Microgravity Using the Bat Model

Abstract

The mode of blood lipid and cortisol expression in simulated microgravity has been poorly understood. This study determined the influence of simulated microgravity (prolonged inversion) on the level of expression of serum cortisol, lipid profile and haematological parameters in bats. Forty bats (Eidolon helvum)were used for this study; they were divided into groups A, B, C and D Groups A, B, C and D were exposed to zero, seven, fourteen and twenty-one days of prolonged inversion respectively. Group A served as the control group. Results of the study showed that prolonged inversion induced the elevation of cortisol and indicated that stress was involved. There was amelioration of atherogenic parameters such that total cholesterol, low density lipoprotein, trigycerides and very low density lipoprotein decreased as prolonged inversion progresses (p< 0.05). But high density lipoprotein increased with the progression of prolonged inversion (p< 0.05). Packed cell volume, haemoglobin concentration, red blood cell counts were significantly decreased with prolonged inversion (p< 0.05). But such parameters were partially ameliorated in the group (D) that underwent twenty-one days of prolonged inversion. This study concludes that simulated microgravity or prolonged inversion in bats is associated with stress, improvement of serum atherogenic indices and decline in haematological parameters, and that bats also showed adaptive responses of its haematological status in the prolonged inversion. This study could be useful in predicting health consequences of extreme environment such as space experienced by astronauts and possible countermeasures.