Antigen Protease Activity on Intact or Tape-Stripped Skin Induces Acute Itch and T Helper Sensitization Leading to Airway Eosinophilia in Mice.

Respiratory allergen sources such as house dust mites frequently contain proteases. In this study, we demonstrated that the epicutaneous application of a model protease antigen, papain, onto intact or tape-stripped ear skin of mice induced acute scratching behaviors and T helper (Th)2, Th9, Th17/Th22, and/or Th1 sensitization in a protease activity-dependent manner. The protease activity of papain applied onto the skin was also essential for subsequent airway eosinophilia induced by an intranasal challenge with low-dose papain. With tape stripping, papain-treated mice showed barrier dysfunction, the accelerated onset of acute scratching behaviors, and attenuated Th17/Th22 sensitization. In contrast, the protease activity of inhaled papain partially or critically contributed to airway atopic march responses in mice sensitized through intact or tape-stripped skin, respectively. These results indicated that papain protease activity on epicutaneous application through intact skin or skin with mechanical barrier damage is critical to the sensitization phase responses, including acute itch and Th sensitization and progression to the airway atopic march, whereas dependency on the protease activity of inhaled papain in the atopic march differs by the condition of the sensitized skin area. This study suggests that exogenous protease-dependent epicutaneous mechanisms are a target for controlling allergic sensitization and progression to the atopic march.

Skin Treatment with Detergent Induces Dermatitis with H1-Antihistamine-Refractory Itch and Upregulates IL-4 and Th17/Th22 Cytokine Gene Expression in C57BL/6 Mice.

INTRODUCTION: Repeated skin contact to detergents causes chronic irritant contact dermatitis (ICD) associated with itch sensation and eczema. However, the mechanisms of detergent-induced ICD are poorly understood. Here, we established a new murine model of detergent-induced ICD with H1-antihistamine-refractory itch. METHODS: Ear skin of wild-type and mast cell-deficient mice on the C57BL/6 genetic background was treated with a detergent, sodium dodecyl/lauryl sulfate (SDS), daily for approximately 2 weeks with or without administration of an H1-antihistamine, fexofenadine. Skin inflammation, barrier dysfunction, and itching were analyzed. Quantitative PCR for earlobe gene expression and flow cytometry analysis for draining lymph node cells were conducted. RESULTS: SDS treatment induced skin inflammation with ear swelling, increased transepidermal water loss, and hind-paw scratching behaviors in the wild-type and mast cell-deficient mice. The peak value of scratching bouts was retained for at least 48 h after the last SDS treatment. H1-antihistamine administration showed no or little reduction in the responses. SDS treatment upregulated gene expression for a Th2 cytokine IL-4 and Th17/Th22 cytokines, IL-17A, IL-17F, and IL-22, and increased cell numbers in draining lymph nodes of CD4+ T, CD8+ T, and γδT cells with enhanced expression of GATA3, RORγt, T-bet, or FOXP3 compared with untreated mice. CONCLUSIONS: The present study showed that SDS treatment of ear skin in C57BL/6 mice induces mast cell-independent skin inflammation with H1-antihistamine-refractory itch and suggested a possible Th cytokine- and/or lymphocyte-mediated regulation of the model. The model would be useful for elucidation of mechanisms for inflammation with H1-antihistamine-refractory itch in detergent-induced ICD.

A Hypothesis for the Pathologic Mechanism of Idiopathic Exophthalmos Based on Computed Tomographic Evaluations.

The causes of idiopathic exophthalmos were still unknown. We used computed tomography to compare the orbital structures of patients with idiopathic exophthalmos and those of a healthy Japanese population. A total of 18 orbits (ranged 17-52 years) in idiopathic exophthalmos and 334 normal orbits (ranged 17-59 years) were included. On computed tomography, the eyeball and orbit sizes, lateral wall thickness and length, perpendicular distance from the interzygomatic line to the medial orbital rim, and the nasal cavity width were measured. No significant differences in eyeball or orbit sizes were found between the idiopathic exophthalmos and control groups (P > 0.05). In contrast, the mean lateral wall thickness of the idiopathic exophthalmos group was significantly thicker than that of the control group (P < 0.01). The lateral wall length was shorter with significant difference (P < 0.05). The perpendicular distance and the width of the nasal cavity in the idiopathic exophthalmos group were longer with significant difference (P < 0.05). The cause of idiopathic exophthalmos is compression of orbital contents by the medial wall expansion. The force of expansion of medial wall also influences the zygoma according to Wolff law.

Management of chronic expanding haematoma using triamcinolone after latissimus dorsi flap harvesting.

Chronic expanding haematoma (CEH) is a rare type of haematoma that enlarges slowly and continuously without coagulation. It can occur following surgery because of shear stress-induced bleeding in the scar tissue between the subcutaneous fat and fascia. We present three cases of large chronic CEH that were successfully treated with triamcinolone injections. Three female patients developed large chronic CEH at 9 months, 5 years, and 6 years, respectively, after latissimus dorsi flap harvesting for breast reconstruction. Although the condition did not improve after multiple sessions of haematoma aspiration in the first two patients, it resolved following a single 40-mg triamcinolone injection along with appropriate compression dressing for several weeks. In the third patient, triamcinolone was injected immediately after the initial aspiration of the haematoma, and the condition improved considerably. There were no side effects in any of the patients. To the best of our knowledge, this is the first report of successful treatment of large CEH using triamcinolone. Therefore, we suggest that triamcinolone injections be considered for the treatment of CEH.

Intra-eyebrow frontalis suspension using inverted Y-shaped short autogenous fascia lata for blepharoptosis with poor levator function.

Frontalis suspension using autogenous fascia lata is a common procedure for blepharoptosis with poor levator function. However, donor-site morbidity associated with fascia lata harvest cannot be ignored. In conventional procedures, the required length of the fascia lata is usually >5-12 cm with a lateral thigh skin incision of approximately 5 cm or more. The present study introduces a new frontalis suspension procedure in which the required size (length and width) of the fascia lata and length of lateral thigh incision is much smaller. The harvested fascia lata is tailored to an inverted Y shape and the separated caudal legs are fixed to the tarsus while the cephalic end is grafted inside the eyebrow through a suborbital septum tunnel. In the present study, 11 patients who underwent the new procedure with a minimum of 6 months of follow-up were evaluated. The average length and width of the harvested fascia lata in unilateral ptosis cases were 2.85 and 0.89 cm, respectively. The average length of the lateral thigh incision was 1.25 cm. The margin reflex distance improved in all cases at 6 months postoperatively. The cosmetic result was graded as good to excellent in most of the patients. Trichiasis, widened donor scar, and eyebrow notch were noted as complications. The present method is a good alternative for the treatment of blepharoptosis with poor levator function. It potentially reduces donor-site morbidity as compared with conventional frontalis muscle suspension procedures using autogenous fascia lata.

Coenzyme Q10 protects against oxidative stress-induced cell death and enhances the synthesis of basement membrane components in dermal and epidermal cells.

Coenzyme Q10 (CoQ10), which has both energizing and anti-oxidative effects, is also reported to have antiaging action, e.g., reducing the area of facial wrinkles. However, the mechanism of its anti-aging activity is not fully established. Here, we examined the effect of CoQ10 on human dermal and epidermal cells. CoQ10 promoted proliferation of fibroblasts but not keratinocytes. It also accelerated production of basement membrane components, i.e., laminin 332 and type IV and VII collagens, in keratinocytes and fibroblasts, respectively; however, it had no effect on type I collagen production in fibroblasts. CoQ10 also showed protective effects against cell death induced by several reactive oxygen species in keratinocytes, but only when its cellular absorption was enhanced by pretreatment of the cells with highly CoQ10-loaded serum. These results suggest that protection of epidermis against oxidative stress and enhancement of production of epidermal basement membrane components may be involved in the antiaging properties of CoQ10 in skin.

Non-invasive study of gelatinases in sun-exposed and unexposed healthy human skin based on measurements in stratum corneum.

Gelatinases, which belong to the family of matrix metalloproteinases, degrade various components of skin, and may be involved in photoaging, since they are upregulated by low-dose UV exposure to the skin. However, their behavior in healthy human skin is still unclear. In the present study, gelatinases was specifically detected in stratum corneum (SC) of skin from sun-exposed sites, including the face, in healthy humans, but not in SC of skin from unexposed sites. Following experimental UVB irradiation of the abdomen in volunteers, gelatinases were detected in tape-stripped SC from the site for several weeks, and subsequently disappeared. The appearance of gelatinase in SC after a lag time consistent with SC turnover is considered to reflect upregulation of gelatinase expression in keratinocytes in response to UVB-exposure of the skin. A survey of gelatinases in facial SC samples collected by tape-stripping from the cheeks of 100 healthy women revealed that the enzyme was present in 90% of subjects. These results, taken together, suggest that gelatinase is constantly upregulated by sunlight in the facial epidermis of most women during their daily lives, and may be an etiological factor in photoaging, e.g., by promoting wrinkle formation.

Possible involvement of gelatinases in basement membrane damage and wrinkle formation in chronically ultraviolet B-exposed hairless mouse.

A number of studies indicate that matrix metalloproteinase might be involved in photoaging, but little is known about their direct contribution to ultraviolet-induced histologic and morphologic changes in the skin in vivo. This study reports the relationship between changes of matrix metalloproteinase activities and ultraviolet B-induced skin changes in hairless mouse. The role of matrix metalloproteinase in the skin changes was studied by topical application of a specific matrix metalloproteinase inhibitor. The backs of mice were exposed to ultraviolet B three times a week for 10 wk. Histologic studies showed that the basement membrane structure was damaged, with epidermal hyperplasia, in the first 2 wk of ultraviolet B irradiation, followed by the appearance of wrinkles, which gradually extended in the latter half of the ultraviolet B irradiation period. We observed enhancement of type IV collagen degradation activity, but not collagenase or matrix metalloproteinase-3 activity, in extracts of ultraviolet B-irradiated, wrinkle-bearing skin. Gelatin zymographic analysis revealed that gelatinases, matrix metalloproteinase-9 and matrix metalloproteinase-2, were significantly increased in the extract. In situ zymographic study clarified that the activity was specifically localized in whole epidermis of ultraviolet B-irradiated, wrinkled skin in comparison with normal skin. The activity was induced around the basal layer of the epidermis by a single ultraviolet exposure of at least one minimal erythema dose. Furthermore, topical application of a specific matrix metalloproteinase inhibitor, CGS27023A, inhibited ultraviolet B-induced gelatinase activity in the epidermis, and its repeated application prevented ultraviolet B-induced damage to the basement membrane, as well as epidermal hyperplasia and dermal collagen degradation. Ultraviolet B-induced wrinkles were also prevented by administration of the inhibitor. These results, taken together, suggest that ultraviolet B-induced enhancement of gelatinase activity in the skin contributes to wrinkle formation through the destruction of basement membrane structure and dermal collagen in chronically ultraviolet B-exposed hairless mouse, and thus topical application of matrix metalloproteinase inhibitors may be an effective way to prevent ultraviolet B-induced wrinkle formation.