Can Sodium Thiosulfate Act as a Reversal Agent for Calcium Hydroxylapatite Filler? Results of a Preclinical Study.

Introduction: Calcium hydroxylapatite microspheres suspended in a gel carrier of sodium carboxymethylcellulose (CaHA; Radiesse) has demonstrated safe and effective restoration of facial volume in clinical trials, as well as collagen biostimulation leading to skin quality improvement. The potential with CaHA, as with any filler, to produce overcorrection and subsequent complications has led to the search for a reversal agent. Sodium thiosulfate (STS) was proposed based on experience with it as a chelating agent to treat calciphylaxis.

EphrinB3 is an anti-apoptotic ligand that inhibits the dependence receptor functions of EphA4 receptors during adult neurogenesis.

Eph receptors have been implicated in regulating a diverse array of cellular functions in the developing nervous system. Recently, Eph receptors have been shown to promote cell death in adult germinal zones; however, their mechanisms of action remain ill-defined. In this study, we demonstrate that EphA4 is a new member of the dependence receptors family, which can initiate cell death in the absence of its ligand ephrinB3.

Netrin-1 is a survival factor during commissural neuron navigation.

DCC (Deleted in Colorectal Cancer) is a putative tumor suppressor whose expression is lost in numerous cancers and whose tumor suppressor activity appears to be dependent on its ability to trigger apoptosis when disengaged by its ligand netrin-1. In this sense, netrin-1 is a survival factor that controls tumorigenesis. However, netrin-1 is also the prototypical axon guidance cue and has been shown to orient many neurons or axons, especially commissural axons, during spinal cord development.

The dependence receptor DCC requires lipid raft localization for cell death signaling.

DCC (deleted in colorectal cancer) is a putative tumor suppressor gene whose expression is lost in numerous cancers. DCC also encodes the main receptor for the neuronal navigation cue netrin-1. It has been shown that DCC belongs to the so-called family of dependence receptors.

DCC association with lipid rafts is required for netrin-1-mediated axon guidance.

During development, axons migrate long distances in responses to attractive or repulsive signals that are detected by their growth cones. One of these signals is mediated by netrin-1, a diffusible laminin-related molecule that both attracts and repels growth cones via interaction with its receptor DCC (deleted in colorectal cancer). Here we show that DCC in both commissural neurons and immortalized cells, is partially associated with cholesterol- and sphingolipid-enriched membrane domains named lipid rafts.