The Effects of Mucopolysaccharide Polysulfate on Steroid-Induced Tight Junction Barrier Dysfunction in Human Epidermal Keratinocytes and a 3D Skin Model.

INTRODUCTION: The long-term use of topical corticosteroids (TCS) is associated with side effects such as skin atrophy and barrier deterioration. Moisturizers, such as mucopolysaccharide polysulfate (MPS), have been reported to prevent relapses in atopic dermatitis (AD) when used in combination with TCS. However, the mechanisms underlying the positive effects of MPS in combination with TCS in AD are poorly understood. In the present study, we investigated the effects of MPS in combination with clobetasol 17-propionate (CP) on tight junction (TJ) barrier function in human epidermal keratinocytes (HEKa) and 3D skin models. METHODS: The expression of claudin-1, which is crucial for TJ barrier function in keratinocytes, and transepithelial electrical resistance (TEER) was measured in CP-treated human keratinocytes incubated with and without MPS. A TJ permeability assay, using Sulfo-NHS-Biotin as a tracer, was also conducted in a 3D skin model. RESULTS: CP reduced claudin-1 expression and TEER in human keratinocytes, whereas MPS inhibited these CP-induced effects. Moreover, MPS inhibited the increase in CP-induced TJ permeability in a 3D skin model. CONCLUSION: The present study demonstrated that MPS improved TJ barrier impairment induced by CP. The improvement of TJ barrier function may partially be responsible for the delayed relapse of AD induced by the combination of MPS and TCS.

Effects of mucopolysaccharide polysulphate on tight junction barrier in human epidermal keratinocytes.

Tight junctions (TJs) play important roles in epidermal barrier function and their dysfunction is involved in the pathogenesis of various skin diseases, including atopic dermatitis (AD). Mucopolysaccharide polysulphate (MPS) is the active ingredient of a moisturizing agent used to treat xerosis in patients with AD; however, its mechanism of action on TJ barrier function remains unclear. To elucidate the effects of MPS on TJs, adult human epidermal keratinocyte (HEKa) cells were exposed to MPS, subjected to Western blotting and quantitative PCR analyses for the investigation of TJ-related factors. MPS treatment significantly increased the mRNA and protein expression of claudin-1 (CLDN1) and zonula occludens-1, and significantly increased transepithelial electrical resistance (TEER), which indicates TJ integrity. Conversely, the sulphated and non-sulphated glycosaminoglycans, chondroitin sulphate and hyaluronic acid, respectively, had little effect on TEER or the expression of mRNAs or TJ-related proteins. Interestingly, MPS treatment also inactivated the extracellular signal-regulated kinase signalling pathway, which is known to negatively regulate CLDN1 expression. Furthermore, MPS notably improved the reduction in CLDN1 expression and TEER caused by histamine, which is upregulated in the skin of patients with AD and is known to disrupt the TJ barrier function. Taken together, these findings demonstrate that treatment with the moisturizing agent, MPS, can repair TJ dysfunction and could therefore represent a new therapeutic option for treating patients with AD.

Altered T cell subpopulations and serum anti-TYRP2 and tyrosinase antibodies in the acute and chronic phase of alopecia areata in the C3H/HeJ mouse model.

BACKGROUND: C3H/HeJ mouse models progress gradually in hair loss from acute to chronic phase and reflect the symptoms of patients with alopecia areata (AA). However, the underlying pathological characteristics alteration associated with disease progression and autoantigens remain unclear. OBJECTIVE: We aimed at elucidating the pathological differences between acute and chronic-AA in the C3H/HeJ mouse model. METHODS: We analyzed populations of PBMCs, skin-draining lymph node (SDLN) cells, and cutaneous cells of AA mice using flow cytometry. The cytokine and chemokine expressions in the serum and skin were determined using multiplex assay and qPCR. The antibody serum levels were determined using ELISA and the antigen-specific T cells were detected using the MHC class I tetramer. RESULTS: The CD8+NKG2D+ T and CD8+ TEM cell percentage in the chronic-AA SDLNs or among the unaffected and acute-AA mice PBMCs increased. The Th1 and CD4+ TEM cell percentage in the SDLNs and among PBMCs increased in the unaffected and AA mice. The percentage of CD8+ TEM/TRM cells and MHC class I expression increased in the lesions of acute-AA or the non-lesions and lesions of chronic-AA. The Th1 cells, dendritic cell-related cytokines, CD11c+ cells and MHC class II expression increased in the skin of AA mice. The antibody levels and TYRP2 and tyrosinase-specific CD8+ T cell percentages were upregulated in AA mice. CONCLUSION: These results suggest that the CD8+ and CD4+ T cell subpopulations, cytokine and chemokine expressions differ between the disease phases. Moreover, TYRP2 and tyrosinase are potential autoreactive targets in the AA mouse model.

Mucopolysaccharide polysulfate promotes microvascular stabilization and barrier integrity of dermal microvascular endothelial cells via activation of the angiopoietin-1/Tie2 pathway.

BACKGROUND: Mucopolysaccharide polysulfate (MPS) is a heparinoid and MPS-containing formulations are widely used as moisturizers for dry skin and to treat peripheral vascular insufficiency. Although MPS has therapeutic effects in skin diseases with microvascular abnormalities, the effects of MPS on microvascular function remain incompletely understood. OBJECTIVE: The aim of this study was to evaluate the functional activities of MPS on human pericytes (HPC) and human dermal microvascular endothelial cells (HDMEC) in vitro, and on microvascular permeability of the skin. METHODS: The protein expression of angiopoietin (Ang)-1 in HPC, and platelet-derived growth factor-BB (PDGF-BB) and phosphorylated tyrosine-protein kinase receptor 2 (Tie2) in HDMEC were measured in the presence or absence of MPS. The vascular barrier was evaluated by the expressions of claudin-5 and vascular endothelial (VE)-cadherin, and transendothelial electrical resistance (TEER). RESULTS: In HPC, MPS dose-dependently enhanced Ang-1 secretion, which activated Tie2 in HDMEC. In HDMEC, MPS significantly increased the production of PDGF-BB, which is important for the recruitment of HPC to the vascular endothelium, and significantly increased the phosphorylation of Tie2, which results in the activation of the Ang-1/Tie2 signaling . MPS significantly increased the expression of tight junction protein claudin-5 and TEER in the HDMEC. Moreover, the intradermal injection of MPS prevented vascular endothelial growth factor-induced increase in vascular permeability in mouse skin. CONCLUSION: We found that MPS promoted microvascular stabilization and barrier integrity in HDMEC via Ang-1/Tie2 activation. These results suggest that MPS might improve microvascular abnormalities in various diseases accompanied by disturbances in Ang-1/Tie2 signaling.

Anti-inflammatory effects of ozenoxacin, a topical quinolone antimicrobial agent.

Ozenoxacin is a topical quinolone showing potent antimicrobial activities against Gram-negative and Gram-positive bacteria and is widely used for the treatment of inflammatory acne. However, the anti-inflammatory activities of ozenoxacin have not been examined so far. In the present study, we investigated the in vitro and in vivo anti-inflammatory effects of ozenoxacin. The production of interleukin (IL)-6 and IL-8 by human epidermal keratinocytes stimulated by heat-killed Cutibacterium acnes was significantly inhibited by ozenoxacin at concentrations from 1 to 30 µg ml-1. Likewise, the production of IL-6, IL-8, and tumor necrosis factor alpha by stimulated THP-1 cells, a human monocyte cell line, was inhibited by ozenoxacin at concentrations from 1 to 30 µg ml-1. The production of IL-1ß by THP-1 was also inhibited by ozenoxacin at the concentration of 30 µg ml-1. Phosphorylation of the mitogen-activated protein kinases and degradation of IκB-α, an inhibitory factor of NF-κB in keratinocytes and THP-1 cells, was increased by stimulation with heat-killed C. acnes. Of these activated intracellular pathways, the p38 phosphorylation pathway was remarkably reduced by ozenoxacin in both keratinocytes and THP-1 cells. In addition, the application of 2% ozenoxacin suppressed the increase in the ear thickness of rats induced by an intracutaneous injection of heat-killed C. acnes. These findings suggest that ozenoxacin possesses an anti-inflammatory activity, which may contribute to its therapeutic effects on inflammatory acne.

[Influence of Bases for External Medicines with Different Coatability and Water Retentivity on Wound Healing].

When selecting external medicines for the treatment of skin diseases, it is thought to be very important to consider differences in characteristics of their bases, because the bases may influence the clinical efficacy of the medicines. In this study, we investigated whether the differences in characteristics of three kinds of bases, white petrolatum, macrogol ointment, and aqueous gel affect wound healing. In vitro moisture permeability tests demonstrated that these bases have different characteristics in coatability and water retentivity, with the rank order of the intensity of coatability as white petrolatum>macrogol ointment>aqueous gel, and that of water retentivity as macrogol ointment>white petrolatum>aqueous gel. Similar rank order of these bases was observed for transepidermal water loss and stratum corneum water content in the dry skin on the abdomen of guinea pigs induced by topical application of acetone/ether mixture, followed by water. In addition, we found that treatment with macrogol ointment, but not white petrolatum or aqueous gel, significantly accelerated wound healing in rat skin, and that the contents of basic fibroblast growth factor and epidermal growth factor in the skin treated with macrogol ointment were significantly higher compared with non-treated skin. In conclusion, these results imply an important role of the bases of external medicines in the treatment of skin diseases.

Characterization of autoantibodies to ferritin in canine serum.

Ferritin-binding proteins circulating in mammalian blood are thought to be involved in the clearance of ferritin. The present study characterizes canine serum autoantibodies (IgM and IgA) that react with ferritin. Canine IgM and IgA bound to bovine spleen ferritin as well as canine liver ferritin. To examine the specificity of canine IgM and IgA to ferritin H and L subunits, we used canine heart ferritin and canine liver ferritin with H/L subunit ratios of 3.69 and 0.43, respectively. Canine IgM and IgA recognized both of the H- and L-subunit-rich isoferritins, showing that their binding activities to ferritin depend on the H-subunit content. Recombinant bovine H-chain ferritin homopolymer expressed in a baculovirus expression system bound more with IgM and IgA than the recombinant L-chain homopolymer expressed under the same conditions. These results suggest that canine IgM and IgA recognize H-subunit-rich isoferritins, and that H-subunit-rich isoferritins are cleared from the circulation more rapidly than L-subunit-rich isoferritins.