Key role of heparan sulfate chains in assembly of anchoring complex at the dermal-epidermal junction
ABSTRACT Epidermal basement membrane forms anchoring complex composed of hemidesmosomes, anchoring filaments, lamina densa and anchoring fibrils to link epidermis to dermis. However, the anchoring complex is rarely formed in skin equivalent models, probably because of degradation of extracellular matrix (ECM) proteins and heparan sulfate chains by matrix metalloproteinases (MMPs) and heparanase, respectively. To explore the roles of ECM proteins and heparan sulfate in anchoring complex assembly, we used specific inhibitors of MMPs and heparanase, and the formation of anchoring complex was analysed in terms of polarized deposition of collagen VII, BP180 and β4 integrin at the dermal-epidermal junction (DEJ) by means of immunohistochemistry and transmission electron microscopy (TEM). The deposition of collagen VII was polarized to the basal side by the addition of MMP inhibitor, and the staining intensity was increased by combined treatment with MMP inhibitor and heparanase inhibitor, which enhanced anchoring fibril formation as observed by TEM. BP180 was polarized to the basal side by heparanase inhibitor, which protects HS chains, but not by MMP inhibitor. MMP inhibitor improved the polarization of β4 integrin. Hemidesmosomes were formed in the presence of each inhibitor, as observed by TEM, and formation was greatly enhanced by the combined treatment. These findings suggest that heparan sulfate chains, in addition to ECM proteins at the DEJ, play an important role in the assembly of anchoring complex, especially hemidesmosomes and anchoring fibrils.
Full-textDOI: · Available from: Satoshi Amano, Sep 23, 2014
- SourceAvailable from: Stanko Skugor
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- "Down-regulation was seen in secretory proteins such as apolipoprotein D (apod, both studies) and acid phosphatase and heparanase (acpl2 and hpse, feeding trial). The latter encodes the proteoglycan degrading enzyme heparanase that is important for secretion (Wang et al., 2011) and formation of ECM (Iriyama et al., 2011). Gene expression profiles suggested a profound effect of sex hormones on the cellular and extracellular structure of skin and interestingly, there were significant differences between the field study (sexual maturation) and feeding trial. "
ABSTRACT: The crustacean ectoparasitic salmon louse (Lepeophtheirus salmonis) is a major problem of Atlantic salmon aquaculture in the Northern hemisphere. Host–pathogen interactions in this system are highly complex. Resistance to the parasite involves variations in genetic background, nutrition, properties of skin, and status of the endocrine and immune systems. This study addressed the relationship between sex hormones and lice infection. Field observation revealed a sharp reduction of lice prevalence during sexual maturation with no difference between male and female fish. To fetermine if higher resistance against lice was related to sex hormones, post-smolt salmon were administered control feed and feeds containing 17β-estradiol (20 mg/kg) and testosterone (25 mg/kg) during a 3-week pre-challenge period. After challenge with lice, counts were reduced 2-fold and 1.5-fold in fish that received 17β-estradiol and testosterone, respectively. Gene expression analyses were performed from skin of salmon collected in the field trial and from the controlled lab experiment at three time points (end of feeding-before challenge, 3 days post challenge (dpc) and 16 dpc) using oligonucleotide microarray and qPCR. Differential expression was observed in genes associated with diverse biological processes. Both studies revealed similar changes of several antibacterial acute phase proteins; of note was induction of cathelicidin and down-regulation of a defensin gene. Treatment with hormones revealed their ability to modulate T helper cell (Th)-mediated immunity in skin. Enhanced protection achieved by 17β-estradiol administration might in part be due to the skewing of Th responses away from the prototypic anti-parasitic Th2 immunity and towards the more effective Th1 responses. Multiple genes involved in wound healing, differentiation and remodelling of skin tissue were stimulated during maturation but suppressed with sex hormones. Such opposite regulation suggested that these processes were not associated with resistance to the parasite under the studied conditions. Both studies revealed regulation of a suite of genes encoding putative large mucosal proteins found exclusively in fish. Marked decrease of erythrocyte markers indicated reduced circulation while down-regulation of multiple zymogen granule membrane proteins and transporters of cholesterol and other compounds suggested limited availability of nutrients for the parasites.General and Comparative Endocrinology 01/2015; 212. DOI:10.1016/j.ygcen.2015.01.002 · 2.67 Impact Factor
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ABSTRACT: Skin pigmentation induced by ultraviolet B radiation is caused in part by inflammation mediated by cytokines secreted from keratinocytes and fibroblasts in the irradiated area. Heparanase is also activated in the irradiated skin, and this leads to loss of heparan sulfate at the dermal-epidermal junction (DEJ), resulting in uncontrolled diffusion of heparan sulfate-binding cytokines through the DEJ. However, it is not clear whether heparanase-induced loss of heparan sulfate at the DEJ is involved in the pigmentation process in sun-exposed skin. We examined the role of heparan sulfate in the pigmentation process of human pigmented skin and in pigmented skin-equivalent model. Heparan sulfate and blood vessels in human pigmented skin, solar lentigo, and non-pigmented skin were evaluated by means of immunohistochemistry. Pigmented skin equivalent models were cultured with or without heparanase inhibitor and the pigmentation levels were compared. In solar lentigo, heparan sulfate was hardly observed, presumably due to the increase of heparanase at the DEJ, in spite of the deposition of core protein of perlecan (also known as heparan sulfate proteoglycan). The number of blood vessels was significantly increased in solar lentigo. In the pigmented skin equivalent model, heparanase inhibitor increased the staining intensity of heparan sulfate at the DEJ and markedly reduced melanogenesis in the epidermis. Our results indicate that heparanase-induced loss of heparan sulfate at the DEJ is involved in the pigmentation process of human skin. Consequently, heparanase inhibitors can be expected to exert a protective effect against ultraviolet exposure-induced skin pigmentation.Journal of dermatological science 12/2011; 64(3):223-8. DOI:10.1016/j.jdermsci.2011.09.007 · 3.34 Impact Factor
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ABSTRACT: Keratinocyte migration is essential for wound repair. Keratin-based products have recently shown stimulatory effects on wound repair. This study was to test the cellular response to wool-derived oxidized keratin in wound healing to further understand the biological mechanisms underlying observed clinical benefits of keratin-based products as wound treatments. In vitro scratch migration assays examined the effects of oxidized keratin on the migration of human skin keratinocytes. Western blotting analysis determined the effects on the marker protein expression of type IV and type VII collagens and keratin 17. We found wool-derived oxidized keratin promoted keratinocyte migration and induced protein expression of type IV and type VII collagens, but not keratin 17. The data suggest that the beneficial effects of keratin-based treatment in wounds may be related to its positive effects on re-epithelialization via stimulating keratinocyte migration and production of basement membrane proteins of types IV and VII collagens.Experimental Dermatology 06/2012; 21(6):458-60. DOI:10.1111/j.1600-0625.2012.01505.x · 4.12 Impact Factor