4,8-Sphingadienine and 4-hydroxy-8-sphingenine activate ceramide production in the skin

<p>Abstract</p> <p>Background</p> <p>Ingestion of glucosylceramide improves transepidermal water loss (TEWL) from the skin, but the underlying mechanism by which a small amount of dietary glucosylceramide can vastly improve skin conditions remains unclear. In a previous report, glucosylceramides were shown to be digested to sphingoids, which were shown to be absorbed through the intestinal epithelium. Based on these observations, we hypothesized that sphingoids are the key molecules facilitating endogenous ceramide production. In this study, we assessed the effect of 4,8-sphingadienine (d18:2) and 4-hydroxy-8-sphingenine (t18:1), derived from konjac glucosylceramide, on stimulating ceramide production.</p> <p>Methods</p> <p>Konjac glucosylceramide acidolysis was performed using hydrochloric acid; the resulting d18:2 and t18:1 were fractionated by column chromatography. Real-time quantitative RT-PCR was performed to assess the effect of d18:2 and t18:1 on gene expression in normal human epidermal keratinocytes, while their effect on the nuclear receptor, peroxisome proliferator-activated receptor (PPAR)γ, was measured using a receptor-cofactor assay system. The effect of d18:2 and t18:1 on stimulating ceramide production was evaluated using HPTLC analysis in a 3-dimensional human skin model.</p> <p>Results</p> <p>We noted the upregulation of genes related to <it>de novo</it> ceramide synthesis as well as of those encoding the elongases of very long-chain fatty acids by d18:2 and t18:1, but not by glucosylceramide and 4-sphingenine. Both these sphingoids also facilitated the expression of PPARβ/δ and PPARγ; moreover, they also demonstrated ligand activity for PPARγ. These results indicated that d18:2 and t18:1 promote the differentiation of keratinocytes. Analysis of the lipids within the 3-dimensional human skin model indicated that treatment with d18:2 and t18:1 not only upregulated gene expression but also increased ceramide production.</p> <p>Conclusions</p> <p>The sphingoids d18:2 and t18:1 activated genes related to <it>de novo</it> ceramide synthesis and increased ceramide production, whereas glucosylceramide and 4-sphingenine could not. These results suggest that the effect of dietary glucosylceramides on the skin is mediated by d18:2 and t18:1.</p

McKeown esophagectomy for a thoracic esophageal carcinoma patient who has a history of definitive chemoradiotherapy for esophageal carcinoma and total pharyngolaryngectomy for hypopharyngeal cancer

Abstract A 64-year-old man, who had previously undergone definitive chemoradiotherapy (dCRT) and endoscopic resections for metachronous multiple esophageal squamous cell carcinoma (ESCC) and had also received total pharyngolaryngectomy (TPL) for hypopharyngeal cancer, was diagnosed with ESCC in the middle thoracic esophagus (cT3N0M0). Thoracoscopic McKeown esophagectomy was performed for the patient. Although the tumor was tightly adherent to the thoracic duct and both main bronchi, they were successfully mobilized. In order to maintain the blood supply to the trachea, we preserved the bilateral bronchial arteries and avoided prophylactic upper mediastinal lymph node dissection. Cervical end-to-side anastomosis between the jejunum and a gastric conduit was performed. Minor pneumothorax was managed conservatively, and the patient was discharged 44 days after the surgery. Overall, thoracoscopic McKeown esophagectomy was safely performed in a patient with a history of TPL and dCRT. Surgeons should be very careful to prevent tracheobronchial ischemia by optimizing the extent of lymph node dissection

A New Sendai Virus Vector Deficient in the Matrix Gene Does Not Form Virus Particles and Shows Extensive Cell-to-Cell Spreading

A new recombinant Sendai virus vector (SeV/ΔM), in which the gene encoding matrix (M) protein was deleted, was recovered from cDNA and propagated in a packaging cell line expressing M protein by using a Cre/loxP induction system. The titer of SeV/ΔM carrying the enhanced green fluorescent protein gene in place of the M gene was 7 × 10(7) cell infectious units/ml or more. The new vector showed high levels of infectivity and gene expression, similar to those of wild-type SeV vector, in vitro and in vivo. Virus maturation into a particle was almost completely abolished in cells infected with SeV/ΔM. Instead, SeV/ΔM infection brought about a significant increase of syncytium formation under conditions in which the fusion protein was proteolytically cleaved and activated by trypsin-like protease. This shows that SeV/ΔM spreads markedly to neighboring cells in a cell-to-cell manner, because both hemagglutinin-neuraminidase and active fusion proteins are present at very high levels on the surface of cells infected with SeV/ΔM. Thus, SeV/ΔM is a novel type of vector with the characteristic features of loss of virus particle formation and gain of cell-to-cell spreading via a mechanism dependent on the activation of the fusion protein

Discovery of Novel 5,5-Diarylpentadienamides as Orally Available Transient Receptor Potential Vanilloid 1 (TRPV1) Antagonists

We have developed a novel and potent chemical series of 5,5-diphenylpentadienamides for targeting TRPV1 in vitro and in vivo. In this investigation, we examined a variety of replacements for the 5-position of dienamides with the goal of addressing issues related to pharmacokinetics. Our data suggest that substitution with alkoxy groups on the phenyl ring at the 5-position increases their ability to penetrate the blood–brain barrier. This investigation culminated in the discovery of compound (<i>R</i>)-<b>36b</b>, which showed a good pharmacokinetic profile. In vivo, compound (<i>R</i>)-<b>36b</b> was found to be effective at reversing mechanical allodynia in rats in a dose-dependent manner, and it reversed thermal hyperalgesia in a model of neuropathic pain induced by sciatic nerve injury