Oral mucosal desquamation caused by two toothpaste detergents in an experimental model

Sodium lauryl sulfate (SLS), the most widely used detergent in toothpastes, has been reported to cause adverse effects on oral soft tissues. This double-blind cross-over study describes the oral mucosal effects of SLS-containing toothpastes and pastes containing a zwitterionic detergent, cocoamidopropyl-betaine (CAPB) in an experimental model in 28 healthy females. Seven toothpastes, differing only in detergent concentration and/or type, were used: SLS (0.5, 1.0, 1.5%), CAPB (0.64, 1.27, 1.90%) and a placebo. Each participant applied 1 cm of assigned test toothpaste via a cap splint to the teeth and the mucosa of the upper jaw. The splints were used twice daily for 2 min during a period of 4 d, after which the participants were examined for oral desquamation. No other oral hygiene was allowed during the test periods. Ten days brushing with a detergent-free toothpaste was performed between each test period. Forty-five desquamative reactions were observed in 21 of 27 subjects (one was excluded) during the trial. Forty-two reactions were recorded during the SLS periods and the remaining three during the CAPB periods. The detergent-free toothpaste did not result in oral desquamation. SLS in toothpastes significantly increased the incidence of desquamation of the oral mucosa compared with toothpastes containing the detergent CAPB. The model used is not directly relevant to normal toothbrushing with toothpaste, but indicates that sensitive patients may contract mucosal irritation through SLS in toothpastes. Less toxic detergents, e.g. CAPB, are desirable in oral hygiene products.     

1141610241Altered expression of HuR, an mRNA stabilizing protein, mediates aberrant Placenta Growth Factor (PlGF) expression in preeclampsia

Background:  Control of mRNA stability is an essential regulatory process in eukaryotic gene expression. HuR, a 3'UTR mRNA binding protein, can protect AU-rich mRNA from degradation in response to stresses. PlGF, an angiogenic growth factor, contains two consensus AU-rich sites suggesting that under normal conditions HuR may protect PlGF mRNA from degradation. Trophoblast expression of PlGF is significantly decreased in preeclampsia and by hypoxia in vitro . We hypothesize that decreased levels of cytoplasmic HuR may contribute to decreased PlGF expression in hypoxic and preeclamptic trophoblast.
Methods:  Western blots were used to determine relative effects of in vitro hypoxia on HuR protein expression and subcellular localization in trophoblast. Immunohistochemistry was used to compare HuR expression patterns in trophoblast of preeclamptic and normal placentae.
Results:  Cytoplasmic expression of HuR was decreased 1.4 fold in the cytoplasm and 1.2 fold in the nucleus of JEG3 cells. A shift in HuR was more apparent in primary trophoblast with a greater than 2-fold decrease in the cytoplasm and a 1.4 fold decrease in the nucleus following 24 hr of hypoxia. Immunohistochemical analyses detected HuR expression in near term trophoblast in situ . However, this technical approach did not detect a significant change in HuR expression between normal and preeclamptic trophoblast.
Conclusions:  HuR expression is decreased in hypoxic trophoblast, at least in vitro , which may provide a causal link to decreased PlGF mRNA expression. Down regulation of trophoblast PlGF expression is thought to contribute to the pathophysiology associated with preeclampsia including the relative lack of perfusion of the placenta and systemic renal effects.