Neuroprotective drug riluzole amplifies the heat shock factor 1 (HSF1)- and glutamate transporter 1 (GLT1)-dependent cytoprotective mechanisms for neuronal survival.

Heat shock factor 1 (HSF1) mediates the cellular response to stress to increase the production of heat shock protein (HSP) chaperones for proper protein folding, trafficking, and degradation; failure of this homeostatic mechanism likely contributes to neurodegeneration. We show that the neuroprotective drug riluzole increased the amount of HSF1 in NG108-15 neuroprogenitor cells by slowing the specific turnover of HSF1 and supporting a more robust and sustained activation of HSF1. Using Hsp70-luciferase as a functional readout of the activity of HSF1, we show that riluzole amplified the heat shock induction of the reporter gene with an optimal increase at 1 μM.

Osteoclasts resorb protein-free mineral (Osteologic discs) efficiently in the absence of osteopontin.

Osteopontin (OPN) is both a matrix protein in mineralized tissues and a cytokine, and it has a pivotal role in osteoclast-mediated bone resorption. Here, using a proprietary hydroxyapatite substitute for bone mineral (Osteologic discs), we investigated the requirement for OPN in mineral resorption. Resorption pits formed in the Osteologic discs, revealed by staining with silver nitrite (Von Kossa stain), were analyzed using the NIH Image J program, which can determine the number of pits formed per unit area, their average size, and the fractional area resorbed.

Control and expression of cystatin C by mouse decidual cultures.

During mouse embryo implantation, trophoblast invasion is controlled in part by a balance of trophoblast-derived proteinases and uterine decidual proteinase inhibitors. Our work has focused on cystatin C, the secreted inhibitor of cathepsins B and L. We have previously shown that cystatin C is synthesized by the uterine decidua and localized to the cells in close contact with the trophoblast during implantation in vivo.