Effects of standardized quassinoid-rich Eurycoma longifolia extract in a rat model of osteoporosis due to testosterone deficiency: A densitometric, morphometric and biomechanical study

Article type: Research Article

Authors: Jayusman, Putri Ayu^a | Mohamed, Isa Naina^a | Alias, Ekram^b | Dom, Sulaiman Md^c | Shuid, Ahmad Nazrun^{a; *}

Affiliations: [a] Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Jalan Yaacob Latif, Cheras, Kuala Lumpur, Malaysia | [b] Department of Biochemistry, Faculty of Medicine, Universiti Kebangsaan Malaysia, Jalan Yaacob Latif, Cheras, Kuala Lumpur, Malaysia | [c] Department of Medical Imaging, Faculty of Health Sciences, Universiti Teknologi MARA, Puncak Alam, Selangor, Malaysia

Correspondence: [*] Corresponding author: Prof. Dr. Ahmad Nazrun Shuid, Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Jalan Yaacob Latif 56000, Cheras, Malaysia. Tel.: +6 0 391459567; Fax: +6 0 291459547; E-mail: [email protected].

Abstract: BACKGROUND:Eurycoma longifolia (EL) is a well-known aphrodisiac herb for men. Recently, the crude extract of EL was reported to possess anti-osteoporotic activities. OBJECTIVE:This study aims to determine the bone protective effects of the standardized quassinoid-rich EL extract in testosterone-deficient rat model. METHODS:Ninety-six intact male Sprague-Dawley rats were randomized into baseline, sham, orchidectomized, and chemically castrated groups. Chemical castration was performed via subcutaneous injection of degarelix at 2 mg/kg. The orchidectomized and degarelix-induced rats were administered with vehicle, intramuscularly injected with testosterone once a week, or orally supplemented with EL extract at doses of 25 mg/kg, 50 mg/kg or 100 mg/kg daily for 10 weeks. Bone mass, microarchitecture and strength were analyzed by dual-energy x-ray absorptiometry (DEXA), micro-CT and three-point bending test. RESULTS:Whole body bone mineral density and femoral bone mineral content significantly increased in testosterone groups (p <  0.05). Micro-CT analysis revealed that trabecular bone volume, number, separation and connectivity density were significantly improved by testosterone administration. However, the structural model index was only improved in degarelix group supplemented with 100 mg/kg EL extract (P <  0.05). The improvement of cortical thickness by EL extract was similar to that of testosterone groups (p <  0.05). Biomechanically, EL extract supplementation was able to improve stiffness, strain and modulus of elasticity in degarelix-induced groups, while stress parameter was significantly improved in orchidectomized groups (p <  0.05). CONCLUSION:Quassinoid-rich EL extract enables to protect against bone loss due to testosterone deficiency. The protective effect on cortical thickness and biomechanical parameters is comparable to testosterone group.

Keywords: Bone mineral, micro-CT, bone strength, bone loss, Tongkat Ali

DOI: 10.3233/XST-17366

Journal: Journal of X-Ray Science and Technology, vol. 26, no. 4, pp. 643-656, 2018