In spite of quercetin advantages, its utilization as a cancer drug is confined due to its very low water solubility and bioavailability. Accordingly, we prepared a biodegradable starch-based hydrogel, using a new technique to control and improve quercetin release and bioavailability. For this purpose, the molecular structure of starch was modified by polyethylene glycol/acrylate and Fe₃O₄ nanoparticles were used to enhance mechanical properties of hydrogel. In order to prepare the final hydrogel drug carrier, the modified starch was directly mixed with quercetin and other additives in different ratios and cured under blue light. Synthesis confirmation and structural properties of the modified starch, silanized and pure Fe₃O₄ nanoparticles and final hydrogel were studied using ¹H NMR, FT-IR, SEM, XRD, TGA, VSM and DLS analyses. We improved in vitro drug release to 56.62%, while the maximum release of quercetin from the starch-based hydrogel in our previous study was only 27% (Doosti et al., 2019).

Objective: In this study we investigate the effects of preconception endurance training with or without voluntary exercise during pregnancy on indices of bone formation and resorption in female offspring bone. Methods: Twenty four C57BL/6 female mice randomly divided into four groups: trained in preconception period and exercised during pregnancy (TE); trained in preconception periods but unexercised during pregnancy (TC); untrained in preconception periods but exercised during pregnancy (CE); untrained and unexercised (CC). Trained dams were subjected to a protocol of moderate exercise training over a period of 4 weeks before pregnancy. Analyses were performed on the adult female offspring that did not have access to running wheels in any portion of their lives. Results: The OPG, Runx2, COLI, ALP and OPN mRNA expression was significantly up-regulated in offspring born to dams that trained in preconception period. However, there was no significant difference in OPG, COLI, Runx2 and ALP expression in TE and TC offspring (P > 0.05). RANKL and osteocalcin expression were significantly down-regulated in TE offspring group (P < 0.001). Conclusions: Improved physical fitness in preconception period results in significant changes in bone gene expressions of female offspring, in particular towards osteogenic responses with improved RANKL/OPG ratio.

International Journal of Endocrinology and Metabolism