Calcium Bioavailability of Opuntia ficus-indica Cladodes in an Ovariectomized Rat Model of Postmenopausal Bone Loss.

Osteoporosis is a disease of the skeletal system characterized by low bone mass and bone weakening, which increase the risk of fracture. This disease is associated with menopause because hypoestrogenism induces the maturation and activation of osteoclasts. In addition, a low dietary intake of calcium leads to low bone mineral density and postmenopausal osteoporosis. The objectives of this work were to determine calcium bioavailability of Opuntia ficus-indica cladodes at a late maturity stage and to assess its contribution in improving bone health in an ovariectomized rat model. Two-month-old Wistar female rats (n = 35) were used and distributed in seven experimental groups: (i) control group (Crtl), (ii) sham group (SH), (iii) ovariectomized group (OVX), (iv) ovariectomized group supplemented with calcium citrate (CCa), (v) ovariectomized group supplemented with O. ficus-indica powder (NI), (vi) ovariectomized group supplemented with soluble fiber from O. ficus-indica (FS) and (vii) ovariectomized group supplemented with insoluble fiber from O. ficus-indica (FI). Our results showed that calcium in the soluble fiber of O. ficus-indica is bioavailable and contributes to improve the physical, densitometric, biomechanical and microstructural properties of bones in ovariectomized rats. These findings indicated that O. ficus-indica cladodes at a late maturity stage represent a good source of bioavailable calcium and consumption of these cladodes might be beneficial for the prevention of osteoporosis and other bone diseases.

Fluorescence decay rate of selected compounds from Eysenhardtia polystachya extracts and their viability as biosensors.

Eysenhardtia polystachya (EP) is an endemic Mexican plant that has been widely studied for its antidiabetic, antibacterial, and antioxidant properties. Several studies had reported the main components of EP, but their fluorescence properties had not been broadly studied. In a previous study we obtained extracts with different composition from this plant and they presented florescence. In this work we study fluorescent compounds from EP and evaluate their fluorescence properties. EP extracts were obtained by Soxhlet extraction with ethanol, samples were dried, and compounds were separated by column chromatography. Fluorescent fractions were classified apart from other fractions and characterized by Scanning electron microscopy (SEM), UV-Vis, Raman, FTIR and 1H NMR spectra. Additionally, we obtained functional nanomaterials (using silica nanoparticles). TD-DFT molecular calculations of the fluorescent components were carried out to compare their theoretical UV-Vis spectra to experimental results. Nine fractions were obtained by chromatography and five of them showed fluorescence. Fluorescence of extracts from Eysenhardtia polystachya is due to more than one component and we suggest that could be other hydrochalcones for which we present possible structures. This finding would help to dissipate questions about which component is responsible for fluorescence in extracts from the plant and in this way determinate the appropriate use for these fluorophores. Finally, the application and viability as a biosensor using pulmonary epithelium fibroblast cell culture IMR-90 was proved, and in the concentration used are non-toxic materials.

Agave fructans: their effect on mineral absorption and bone mineral content.

In this study we investigate the effect that Agave fructans as new prebiotics have on mineral absorption improvement. Forty-eight 12-week-old C57BL/6J mice were used in this study. Forty mice were ovariectomized and eight were sham-operated controls. Mice were fed standard diets or diets supplemented with 10% Agave fructans or 10% inulin fructans. Calcium and magnesium were evaluated as well as their excretion in feces. Osteocalcin levels were also measured; femur structure was studied by scanning electron microscopy. Other parameters, such as food intake, body weight, glucose, and short-chain fatty acid content, were recorded. Calcium in plasma and bone increased in Agave fructan groups (from 53.1 to 56 and 85 mg/L and from 0.402 to 0.474 and 0.478 g/g, respectively) and osteocalcin increased in all fructan groups (>50%). Scanning electron microscopy showed that fructans were able to mitigate bone loss. In conclusion, we demonstrated that supplementation with Agave fructans prevents bone loss and improves bone formation.