bone-protective effect of a Taiwanese yam (Dioscorea alata L. cv. Tainung No. 2) in ovariectomised female BALB/C mice

• Published in: Journal of the science of food and agriculture 2009-02, Vol.89 (3), p.517-522
• Main Authors: Chen, Hsiao-ling, Hong, Ling-tiao, Kang Lee, Jong, Huang, Ching-jang
• Format: Article
• Language: English
• Subjects: ash content; Biochemistry; Biological and medical sciences; Bone density; bone mineral density; bone resorption; Bones; calcium; cecum; Diet; Dioscorea alata; fatty acid composition; Fatty acids; Food industries; food intake; Fundamental and applied biological sciences. Psychology; genistein; mice; mineral content; ovariectomised; ovariectomy; protective effect; Rodents; short chain fatty acid; yam; yams
• ISSN: 0022-5142; 1097-0010
• DOI: 10.1002/jsfa.3489

BACKGROUND: Yam products have been marketed for treating postmenopausal syndromes. This study investigated the effects of Dioscorea alata L. cv. Tainung No. 2 (TNG yam) on the bone density of ovariectomised (OVX) female BALB/c mice and the mechanism whereby TNG yam exerted this effect. Sham and OVX control groups were fed a control diet while remaining OVX mice were randomly allocated into experimental diets, i.e. yam (630 g TNG powder kg⁻¹), E2 (20 mg 17β-oestradiol kg⁻¹), or genistein (2 g genistein kg⁻¹) diet. After 12 weeks of feeding, the uterine weight, indices of bone mass and caecal short chain fatty acids were determined.RESULTS: Neither a yam nor genistein diet restored the OVX-induced uterine atrophy as did the E2 diet. The femoral and lumbar bone mineral density (BMD) of mice fed the yam diet was greater than those of the sham group, respectively (P < 0.05 vs OVX control), while the lumbar BMD of yam and sham groups were similar (P > 0.05 vs sham). The femoral ash and calcium content in the yam group was significantly greater than that in the OVX control group, respectively (P < 0.05 vs OVX control). The total short chain fatty acid content in the caecum, only enhanced in the yam group, was not correlated with the calcium content of either bone or the plasma calcium level.CONCLUSION: TNG yam prevented loss of BMD and improved bone calcium status without stimulating uterine hypertrophy in OVX BALB/c mice. TNG yam may be beneficial for postmenopausal women for preventing bone loss.