Comparison of skin calming effects of cosmetic products containing 4-t-butylcyclohexanol or acetyl dipeptide-1 cetyl ester on capsaicin-induced facial stinging in volunteers with sensitive skin.

OBJECTIVE: To assess and compare the skin calming effect of cosmetic products containing 4-t-butylcyclohexanol (Eucerin(®) UltraSensitive Soothing Care Dry Skin) or acetyl dipeptide-1 cetyl ester (La Roche-Posay Toleriane(®) Ultra Intense Soothing Care) on subjective symptoms of skin sensitivity, a controlled, single-blind, randomized split-face capsaicin-induced stinging test was conducted. METHODS: Thirty-one female test subjects, ranging from 19 to 65 years of age, with self-perceived sensitive to very sensitive skin were enrolled. After a 3-day preconditioning period with no application of facial products and positive reaction to stimulation with a 40 ppm capsaicin cream, the test products were randomly applied to either the right or left nasolabial fold. Burning severity was assessed immediately after capsaicin application, and 1, 2, 5, 10 and 15 min after application of the test products. RESULTS: All 31 subjects reported a stinging/burning sensation on both nasolabial folds after application of capsaicin. Treatment with the 4-t-butylcyclohexanol containing product resulted in significant lower values for burning/stinging after one, and two minutes post-application in comparison to the values for the acetyl dipeptide-1 cetyl ester containing product. No significant difference was determined between the two test products for the point in time with most intense burning sensation, the severity of burning and the duration of burning after capsaicin application and subsequent application of the test products. CONCLUSION: Both products alleviated capsaicin-induced burning during the first 15 min after application. A faster and more pronounced soothing effect in vivo was demonstrated for the 4-t-butylcyclohexanol containing cosmetic product in comparison to the acetyl dipeptide-1 cetyl ester containing cosmetic formulation.

Perlecan in human bone marrow: a growth-factor-presenting, but anti-adhesive, extracellular matrix component for hematopoietic cells.

Human perlecan is a heparan sulfate proteoglycan with a large core protein of 467 kDa to which three glycosaminoglycan side chains are attached. It belongs to the heparan sulfate proteoglycan family which has been implicated in strong interactions between developing hematopoietic cells and their microenvironment in the bone marrow. Here we report that perlecan is highly expressed in the human bone marrow, as well as in long-term bone marrow cultures which are thought to mimic hematopoiesis in vitro. Expression of perlecan in this tissue was shown by Northern blotting of the 14-kb mRNA of the core protein and by immunofluorescence stainings. Functionally, perlecan shows a strong anti-adhesive effect on unfractionated bone marrow cells and on various hematopoietic cell lines, repelling the cells from the perlecan-coated area. In contrast, perlecan is adhesive for fibroblasts and endothelial cells. It is suggested that the anti-adhesive site is located within the core protein of perlecan since heparitinase-treated perlecan still shows the repellent effect. Although anti-adhesive for hematopoietic cells, perlecan is able to bind growth factors like granulocyte/macrophage-colony stimulating factor and present them to hematopoietic progenitor cells in a semi-solid colony assay. The functional role of a growth-factor-binding extracellular matrix component in the bone marrow microenvironment with anti-adhesive properties is uncertain but may be related to compartmentalization.

Small subfamily of olfactory receptor genes: structural features, expression pattern and genomic organization.

Olfactory receptors of the OR37 subfamily are characterized by distinct sequence features and are expressed in neurons segregated in a restricted area of the olfactory epithelium. In the present study, we have characterized the complement of OR37-like genes in the mouse. Five OR37-like genes were identified. They reside within only 60kb of DNA on chromosome 4. About 70kb distant from this cluster, two additional olfactory receptor genes are located, which are members of distinct receptor subfamilies. Phylogenetic analysis demonstrated that the two physically linked receptors are closely related to the OR37 subfamily. Studies of gene expression showed that both genes are also expressed in clustered neuron populations located in the typical OR37 region of the epithelium. These data suggest the involvement of locus-dependent mechanisms for the spatial control of OR gene expression.

Identification of a nonmammalian Golf subtype: functional role in olfactory signaling of airborne odorants in Xenopus laevis.

Attempts to identify the Galpha subtypes in the two compartments of the olfactory system from Xenopus, which are supposed to be specialized for detecting aquatic and volatile odorous compounds, revealed that a Galpha(o1) subtype is characteristic for the "water nose," the lateral diverticulum, whereas a novel Galpha(s) subtype predominates in the "air nose," the medial diverticulum. The newly identified Galpha(s)-type is more closely related to Galpha(olf) of rat and human than to the known Galpha(s)-isoform of Xenopus; it is therefore considered the first identified nonmammalian Galpha(olf) subtype. Sequence comparison of Galpha(olf) from amphibia and mammals revealed a particular conservation within the alpha-helical domains, which are supposed to control the GDP/GTP-exchange rate. The selective expression of different Galpha subtypes in the two anatomically separated and functionally specialized nasal compartments parallels the expression of distinct classes of olfactory receptors. Moreover, biochemical analysis revealed that stimulation with appropriate odorous compounds elicits the formation of inositol trisphosphate in the lateral diverticulum. In contrast, cyclic adenosine monophosphate signals were induced in the medial diverticulum, and this response appears to be mediated by the novel Galpha(olf) subtype. The data indicate that olfactory sensory neurons in each of the nasal cavities are equipped not only with defined sets of receptor types but also with a distinct molecular machinery for the chemo-electrical transduction process.

Brain targeting and glomerulus formation of two olfactory neuron populations expressing related receptor types.

Olfactory sensory neurons expressing different members of the mOR37 odourant receptor subfamily send their axons to distinct glomeruli located in the immediate vicinity in the olfactory bulb [Strotmann, J., Conzelmann, S., Beck, A., Feinstein, P., Breer, H. & Mombaerts, P. (2000) J. Neurosci., 20, 6927-6938]. In this study, the potential of transgenic mouse lines was used to explore the onset of receptor expression, the outgrowth of axons as well as the glomerulus formation for two neuron populations expressing different mOR37 subtypes. The data indicate a synchronous time course of these features for both neuron populations. From E15 until the day of birth, the axons of the two mOR37 populations terminate in a common, small area of the presumptive olfactory bulb. During a short postnatal phase, the two axon populations segregate into distinct, protoglomerular structures; some aberrant fibers can still be observed during this period.

Local permutations in the glomerular array of the mouse olfactory bulb.

Olfactory sensory neurons expressing a given odorant receptor gene project their axons with great precision to a few specific glomeruli in the olfactory bulb. It is not clear to which extent the positions of these glomeruli are fixed. We sought to evaluate the constancy of the glomerular array in the mouse by determining the relative positions of glomeruli for various odorant receptors, using a method that affords single-axon resolution, and in a large number of bulbs. We used a genetic strategy to visualize neuronal populations that express one of three members of the mOR37 subfamily. We generated by gene targeting five strains of mice in which expression of a given mOR37 gene is linked to expression of an axonal maker, which is either taulacZ or tauGFP. The patterns of marker expression faithfully mimic those of the cognate receptors. Axons of neurons expressing a given mOR37 gene converge onto one or two glomeruli per bulb. Each mOR37 gene has its own glomeruli, and the mOR37 glomeruli are grouped within a restricted domain of the bulb. Serial sectioning of 214 bulbs reveals that the relative positions of the three types of glomeruli are not fixed but display local permutations. Importantly, this is also the case among the two bulbs from one individual, ruling out the genetic manipulation itself and differences in genetic background or olfactory experience as causes for the observed variability. These local permutations may reflect the developmental history of the glomeruli and are relevant for the construction of spatial odor maps.

Monoclonal antibodies against laminin A chain fragment E3 and their effects on binding to cells and proteoglycan and on kidney development.

Rat monoclonal antibodies were raised against fragment E3 of the mouse Engelbreth-Holm-Swarm (EHS) tumor laminin and selected according to their exclusive reaction with laminin A chain by immunoblotting and staining pattern in embryonic kidneys by immunofluorescence. Immunochemical studies of nine purified antibodies showed a comparable reaction with unfragmented laminin and fragment E3 but no cross-reaction with several other, unrelated laminin fragments including the major cell-binding fragment E8. Reduction or pepsin digestion of fragment E3 reduced or abolished antibody binding indicating that most of the epitopes involved are conformation dependent and do not include carbohydrates. They are, however, not identical as shown by different reactivities after proteolytic or chemical cleavage of E3. Four of the antibodies were highly active in inhibiting cell adhesion of the teratocarcinoma cell line F9 and the Schwannoma cell line RN22 on fragment E3 (IC50 approximately 1 microgram/ml), while the others were distinctly less active. No inhibition was observed for cell adhesion on unfragmented laminin, consistent with previous findings that this is largely mediated by binding of fragment E8 to alpha 6 beta 1 integrin. A distinct correlation was observed between cell adhesion inhibition and the inhibition of heparansulfate proteoglycan and heparin binding to fragment E3. Since heparin is not very efficient in inhibiting cell adhesion, it indicates that heparin- and cell-binding sites on fragment E3 are in close proximity but not identical. Two of the antibodies also showed partial inhibition of kidney tubule formation in organ culture of embryonic kidney mesenchyme while the other antibodies were inactive. It suggests some but probably minor involvement of the fragment E3 structure of laminin in this developmental process.

A novel brain receptor is expressed in a distinct population of olfactory sensory neurons.

Three novel G-protein-coupled receptor genes related to the previously described RA1c gene have been isolated from the mouse genome. Expression of these genes has been detected in distinct areas of the brain and also in the olfactory epithelium of the nose. Developmental studies revealed a differential onset of expression: in the brain at embryonic stage 17, in the olfactory system at stage E12. In order to determine which cell type in the olfactory epithelium expresses this unique receptor type, a transgenic approach was employed which allowed a coexpression of histological markers together with the receptor and thus visualization of the appropriate cell population. It was found that the receptor-expressing cells were located very close to the basal membrane of the epithelium; however, the cells extended a dendritic process to the epithelial surface and their axons projected into the main olfactory bulb where they converged onto two or three glomeruli in the dorsal and posterior region of the bulb. Thus, these data provide evidence that this unique type of receptor is expressed in mature olfactory neurons and suggests that it may be involved in the detection of special odour molecules.