title: The Effects of Annatto Tocotrienol on Bone Biomechanical Strength and Bone Calcium Content in an Animal Model of Osteoporosis Due to Testosterone Deficiency.
abstract: Osteoporosis reduces the skeletal strength and increases the risk for fracture. It is an underdiagnosed disease in men. Annatto tocotrienol has been shown to improve bone structural indices and increase expression of bone formation genes in orchidectomized rats. This study aimed to evaluate the effects of annatto tocotrienol on biomechanical strength and calcium content of the bone in orchidectomized rats. Thirty three-month-old male Sprague-Dawley rats were randomly assigned to five groups. The baseline control (BC) group was sacrificed at the onset of the study. The sham-operated group (SHAM) received olive oil (the vehicle of tocotrienol) orally daily and peanut oil (the vehicle of testosterone) intramuscularly weekly. The remaining rats were orchidectomized and treated with three different regimens, i.e., (1) daily oral olive oil plus weekly intramuscular peanut oil injection; (2) daily oral annatto tocotrienol at 60 mg/kg plus weekly intramuscular peanut oil injection; (3) daily oral olive oil plus weekly intramuscular testosterone enanthate injection at 7 mg/kg. Blood, femur and tibia of the rats were harvested at the end of the two-month treatment period for the evaluation of serum total calcium and inorganic phosphate levels, bone biomechanical strength test and bone calcium content. Annatto-tocotrienol treatment improved serum calcium level and tibial calcium content (p< 0.05) but it did not affect femoral biomechanical strength (p> 0.05). In conclusion, annatto-tocotrienol at 60 mg/kg augments bone calcium level by preventing calcium mobilization into the circulation. A longer treatment period is needed for annatto tocotrienol to exert its effects on bone strength.
authors.affiliation: Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre, Cheras 56000, Malaysia. chinkokyong@ppukm.ukm.edu.my.
authors.forename: Kok-Yong
authors.initials: KY
authors.lastname: Chin
authors.affiliation: Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre, Cheras 56000, Malaysia. dhiva09@gmail.com.
authors.forename: Dhivakaran
authors.initials: D
authors.lastname: Gengatharan
authors.affiliation: Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre, Cheras 56000, Malaysia. fadlinsakina@yahoo.com.
authors.forename: Fadlin Sakina
authors.initials: FS
authors.lastname: Mohd Nasru
authors.affiliation: Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre, Cheras 56000, Malaysia. rehanamaliakhairussam@gmail.com.
authors.forename: Rehan Amalia
authors.initials: RA
authors.lastname: Khairussam
authors.affiliation: Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre, Cheras 56000, Malaysia. sherlynlaihe@gmail.com.
authors.forename: Sherlyn Lai Hui
authors.initials: SL
authors.lastname: Ern
authors.affiliation: Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre, Cheras 56000, Malaysia. Aina_aminuddin93@yahoo.com.
authors.forename: Siti Aina Wahidah
authors.initials: SA
authors.lastname: Aminuddin
authors.affiliation: Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre, Cheras 56000, Malaysia. imasoel@ppukm.ukm.edu.my.
authors.forename: Soelaiman
authors.initials: S
authors.lastname: Ima-Nirwana
mesh_terms: D000728:Androgens / Q000008:administration & dosage; D000818:Animals; D031212:Bixaceae; D015519:Bone Density / Q000187:drug effects; D001842:Bone and Bones / Q000737:chemistry / Q000187:drug effects*; D002118:Calcium / Q000032:analysis* / Q000097:blood; D002338:Carotenoids / Q000494:pharmacology*; D004195:Disease Models, Animal; D005269:Femur / Q000187:drug effects; D008297:Male; D009919:Orchiectomy; D010024:Osteoporosis / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D010936:Plant Extracts / Q000494:pharmacology*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013739:Testosterone / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000172:deficiency; D013977:Tibia / Q000187:drug effects; D024508:Tocotrienols / Q000494:pharmacology*
chemical_list: D000728:Androgens; D010936:Plant Extracts; D024508:Tocotrienols; D002338:Carotenoids; D013739:Testosterone; C054041:annatto; C004648:testosterone enanthate; D002118:Calcium
keywords: antioxidant; calcium; orchidectomy; phosphate; vitamin E