The phytoestrogen glabrene prevents osteoporosis in ovariectomized rats through upregulation of the canonical Wnt/beta-catenin signaling pathway
JOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY
Authors: Liu, Jun; Deng, Xinchang; Liang, Xiao; Li, Longying
Abstract
This study systematically investigated the effects of phytoestrogen glabrene on postmenopausal osteoporosis in an ovariectomy (OVX) rat model. Glabrene administration (25, 50, and 100 mg/kg) for 13 weeks can significantly slow down the body weight gain and slightly increase the uterus weight of OVX rats. The increased levels of U-Ca, U-P levels, urine DPD/creatinine, serum ALP, OCN, triglycerides, and total cholesterol induced by OVX were dramatically inhibited in rats, whereas no difference occurred for S-Ca and S-P in all groups. Furthermore, glabrene can enhance bone mineral density of the right femur, fourth-lumbar vertebra and tibia and improve biomechanical parameters, such as femoral neck loading force, three-point bending of the tibia, and vertebral compression in OVX rats. Moreover, glabrene greatly suppressed the expression of TRAP protein but increased OPG and BGP protein expression in tibia tissue of OVX rats. In addition, OVX-induced reduction of Lrp-5, beta-catenin, Runx2, and Osx protein expression was all restored by glabrene treatment. The present study indicated that glabrene might be a potential alternative medicine for the prevention and treatment of postmenopausal osteoporosis via activation of the Wnt/beta-catenin signaling pathway.
In Situ Controllable Generation of Copper Nanoclusters Confined in a Poly-L-Cysteine Porous Film with Enhanced Electrochemiluminescence for Alkaline Phosphatase Detection
ANALYTICAL CHEMISTRY
Authors: Pan, Mei-Chen; Lei, Yan-Mei; Chai, Ya-Qin; Yuan, Ruo; Zhuo, Ying
Abstract
Copper nanoclusters (Cu NCs) as emerging luminescent metal NCs are gaining increasing attention owing to the comparatively low cost and high abundance of the Cu element in nature. However, it remains challenging to manipulate the optical properties of Cu NCs. Unlike most dispersed Cu NCs, whose luminescence efficiency was restricted by nonexcited relaxation, the Cu NCs confined in a porous poly-L-cysteine (poly-L-Cys) film were generated controllably with enhanced electrochemiluminescence (ECL) by in situ electrochemical reduction. Specifically, poly-L-Cys provided a porous structure to regulate the generation of Cu NCs within its holes, which not only increased the restriction on the intramolecular vibration and rotation of the ligands but also expedited the electron transfer near the electrode surface, reflecting in an enhancement of the ECL signal and efficiency. As an application of the confined Cu NCs, an ECL biosensor with high performance was constructed skillfully for highly sensitive detection of alkaline phosphatase (ALP), which adopted Cu NCs as the ECL luminophore and poly-L-Cys as a coreaction accelerator in a novel ECL ternary system (Cu NCs/S2O82-/poly-L-Cys). Furthermore, an ingenious target amplification based on the combination of a DNA walker and click chemistry was developed to convert ALP to DNA strands efficiently, achieving great improvement in the recognition efficiency. As a result, the biosensor had a low detection limit (9.5 x 10(-7) U.L-1) and a wide linear range (10(-8)-10(-2) U.L-1) for ALP detection, which showed great promise for the detection of non-nucleic acid targets and the diagnosis of diseases.