Effects of Maca Extract on Exercise Endurance and Ultrastructure of Mitochondria in Spinal Neurons

[Objectives] To study the effects of maca extract on the exercise endurance and ultrastructure of mitochondria in spinal neurons.[Methods]First,50 Wistar rats were randomly divided into 5 groups. The control group: no swimming,administered intragastrically the same volume of distilled water; simple swimming group: free swimming,administered intragastrically the same volume of distilled water; maca extract groups: free swimming,and treated with 4. 0,5. 3,and 8. 0 g/kg dose of maca extracts. Swimming rats swam freely in the circulating water flow of swimming pool and administered for 15 d. On the 16 th d,after the swimming endurance test,the rats were killed painlessly. The ultrastructure of the mitochondria in the spinal neurons was observed with a projection electron microscope,muscle glycogen,malondialdehyde( MDA),superoxide dismutase( SOD),glutathione peroxidase( GSH-Px) and free calcium in muscle were measured by radioimmunoassay.[Results] Compared with the simple swimming group,the swimming time before sinking and total swimming time extended 19. 83%,60. 28%,77. 55% and 55. 34%,73. 91% and 94. 47% respectively,and the differences were statistically significant( P < 0. 01). The sinking times decreased by 34. 35%,51. 18% and 57. 96% respectively,the differences were statistically significant( P < 0. 01). MDA and free calcium decreased by 20. 10%,31. 49% and 38. 72%,respectively with statistically significant differences( P < 0. 01) and 6. 42%,17. 58%and 26. 35% respectively. The levels of SOD,GSH-Px and muscle glycogen increased by 5. 12%,22. 74%,52. 53%,44. 22%,77. 79%and 98. 45% respectively,with statistically significant differences( P < 0. 01) and 35. 08%,47. 83% and 81. 88%,respectively,with statistically significant differences( P < 0. 01). The volume density( Vd),surface density( Sd) and number density( Nd) of mitochondria of spinal neurons decreased by 7. 79%,18. 18%,31. 17%,16. 95%,27. 34%,43. 31% and 13. 51%,23. 19% and 43. 15% respectively.[Conclusions]Maca extract can protect ultrastructure of the mitochondria in the spinal neurons,antioxidant activity,increase muscle glycogen,and improving the exercise capacity.

Effects of Maca Extract on Endurance and Blood Antioxidant Enzyme Activity of Rats

[Objectives] The aim was to investigate the effects of maca extract on endurance and blood antioxidative enzyme activity of rats.[Methods]The Wistar rats treated with/without maca extract( 8. 0,16. 0,and 32. 0 g/kg) were given with free access to circulating water.The administration was conducted for 15 consecutive d. On the 16 th d,the endurance and blood malondialdehyde( MDA),superoxide dismutase( SOD) and glutathione peroxidase( GSH-Px) levels of the rats were determined. [Results] Compared with those of the rats without maca extract treatment,the swimming time before sinking of the rats administered with 8. 0,16. 0,and 32. 0 g/kg of maca extract was increased by 34. 38%,84. 25% and 126. 07%( P < 0. 01),the total swimming time was increased by 37. 42%,47. 03% and 107. 24%( P <0. 01),the times of sinking was reduced by 17. 65%,33. 28% and 55. 50%( P < 0. 05,P < 0. 01),the blood MDA level was reduced by 34.63%,54. 13% and 63. 73%( P < 0. 01),the blood SOD activity was increased by 67. 78%,108. 25% and 154. 49%( P < 0. 01),and the blood GSH-Px level was increased by 48. 57%,110. 28% and 154. 86%( P < 0. 01). [Conclusions]Maca extract has the functions of resisting fatigue and enhancing athletic,and the mechanisms are related to the reduction of blood MDA level and the increase of blood SOD and GSH-Px activity.