Effects of ovariectomy and calcium enriched pumpkin on magnesium status in rats

Background. Calcium (Ca) and magnesium (Mg) are important components of bones, whose homeostasis is disturbed during menopause. Calcium and magnesium metabolism are closely related, so it is important to study the interactions between them. This study aimed to determine the effect of Ca-enriched pumpkin on the Mg content in tissues in an animal model of postmenopausal osteoporosis.
Material and methods. 70 female Wistar rats divided into seven groups. One group was fed a standard diet (C), whereas the other six groups were ovariectomized and fed a standard diet (OVX), a calcium-deficient diet (DEF), a calcium lactate diet (CaL), calcium-lactate-enriched pumpkin (P_CaL), calcium lactate and alendronate (CaL_B), or calcium-lactate-enriched pumpkin and alendronate (P_CaL_B). This nutritional intervention was followed for 12 weeks, and then the rats were euthanized. Tissue samples were collected, and their magnesium content was assessed.
Results. The Mg content in bones was lower in the OVX group (3.15 ±0.19 mg/g) but higher in the DEF group (3.76 ±0.16 mg/g) in comparison with the control group (3.45 ±0.15 mg/g). The Mg content in the muscles and the liver was higher in the P_CaL group (1025.24 ±47.22 μg/g and 2102.09 ±83.35 μg/g) compared with the control group (842.51 ±19.13 μg/g and 1486.15 ±97.12 μg/g). However, the CaL_B and P_CaL_B groups showed a high Mg content in the kidneys (about 156% of the control group).
Conclusion. Ovariectomy and intervention diets revealed various new observations regarding the effect of innovative calcium-rich foods on the Mg content. These results showed that (i) ovariectomy decreases the status of Mg content; (ii) deficiency of Ca in the diet and Ca-enriched pumpkin with alendronate improve the Mg content in bones; and (iii) alendronate promotes the accumulation of Mg in the kidneys. In postmenopausal women, both those treated and untreated with drugs and diet, magnesium status should be monitored.