Effects of Eurycoma longifolia on Testosterone Level and Bone Structure in an Aged Orchidectomised Rat Model

Abstract

Testosterone replacement is the choice of treatment in androgen-deficient osteoporosis. However, long-term use of testosterone is potentially carcinogenic. Eurycoma longifolia (EL) has been reported to enhance testosterone level and prevent bone calcium loss but there is a paucity of research regarding its effect on the bone structural parameters. This study was conducted to explore the bone structural changes following EL treatment in normal and androgen-deficient osteoporosis rat model. Thirty-six male Sprague-Dawley rats aged 12 months were divided into normal control, normal rat supplemented with EL, sham-operated, orchidectomised-control, orchidectomised with testosterone replacement, and orchidectomised with EL supplementation groups. Testosterone serum was measured both before and after the completion of the treatment. After 6 weeks of the treatment, the femora were processed for bone histomorphometry. Testosterone replacement was able to raise the testosterone level and restore the bone volume of orchidectomised rats. EL supplementation failed to emulate both these testosterone actions. The inability of EL to do so may be related to the absence of testes in the androgen deficient osteoporosis model for EL to stimulate testosterone production.

Figure 1

Mean body weight throughout the study. Data presented as mean ± SEM. There was no significant difference in the body weights between the groups. NC: normal control, EL: supplemented with EL.

Figure 2

Mean body weight throughout the study. Data presented as mean ± SEM. All the groups have gained weight at the end of the study except OrxC group. There was no significant difference in the body weights between the groups. Sham: sham-operated, OrxC: orchidectomised-control, Orx + T: orchidectomised and given testosterone replacement, Orx + EL: orchidectomised and supplemented with EL.

Figure 3

Mean testosterone level (ng/mL) at week 0 and week 6. Data presented as mean ± SEM. There was no significant difference in the serum testosterone levels between the groups. NC: normal control, EL: supplemented with EL.

Figure 4

Mean testosterone level (ng/mL) at week 0 and week 6. Data presented as mean ± SEM (P < 0.05). *Significant difference of testosterone level at week 6 compared to Sham and Orx + T groups. Sham: sham-operated, OrxC: orchidectomised-control, Orx + T: orchidectomised and given testosterone replacement, Orx + EL: orchidectomised and supplemented with EL.

Figure 5

Mean trabecular bone volume for both groups. Data presented as mean ± SEM. There was no significant findings between the groups. NC: normal control, EL: supplemented with EL.

Figure 6

Mean trabecular thickness for both groups. Data presented as mean ± SEM. There was no significant difference in trabecular thickness between the groups. NC: normal control, EL: supplemented with EL.

Figure 7

Mean trabecular number for both groups. Data presented as mean ± SEM. There was no significant difference in trabecular number between the groups. NC: normal control, EL: supplemented with EL.

Figure 8

Mean trabecular separation for both groups. Data presented as mean ± SEM. There was no significant difference in trabecular separation between the groups. NC: normal control, EL: supplemented with EL.

Figure 9

Mean trabecular bone volume for all the groups. Data presented as mean ± SEM. *Significant difference of BV/TV compared to Sham and Orx + T groups. Sham: sham-operated, OrxC: orchidectomised-control, Orx + T: orchidectomised and given testosterone replacement, Orx + EL: orchidectomised and supplemented with EL.

Figure 10

Mean trabecular thickness for all the groups. Data presented as mean ± SEM. There was no significant difference in trabecular thickness between the groups. Sham: sham-operated, OrxC: orchidectomised-control, Orx + T: orchidectomised and given testosterone replacement, Orx + EL: orchidectomised and supplemented with EL.

Figure 11

Mean trabecular number for all the groups. Data presented as mean ± SEM. There was no significant difference in trabecular number between the groups. Sham: sham-operated, OrxC: orchidectomised-control, Orx + T: orchidectomised and given testosterone replacement, Orx + EL: orchidectomised and supplemented with EL.

Figure 12

Mean trabecular separation. Data presented as mean ± SEM. There was no significant difference in trabecular separation between the groups. Sham: sham-operated, OrxC: orchidectomised-control, Orx + T: orchidectomised and given testosterone replacement, Orx + EL: orchidectomised and supplemented with EL.