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Background: Psoriasis is a chronic inflammatory skin disorder of unknown etiology. Increasing evidence suggests that psoriasis is probably an angiogenesis-dependent disease. Thalidomide has been reported being able to inhibit the effects of fibroblast growth factor 2 and vascular endothelial growth factor (VEGF), and inhibit tumour necrosis factor-alpha synthesis, and suppress tumour necrosis factor-induced nuclear factor-kappa B activation in Jurkat cells, resulting in suppression of proliferation inflammation, angiogenesis, and the immune system, which are related to the pathogenesis of psoriasis., Objective: Our study evaluated the influence of thalidomide on the lesional alterations, VEGF expressions and angiogenesis in imiquimod-induced mouse model., Methods: Balb/c female mice (n=48) 8-12 weeks of age were randomly divided into 6 groups including negative control (vaseline cream), positive control (5% imiquimod cream), and experimental groups including low-dose (10 mg/kg.d), moderate-dose (30 mg/kg.d) and high-dose thalidomide (85 mg/kg.d), and acitretin group (6 mg/kg.d). Serum levels of VEGF-A were quantified by enzyme-linked immunosorbent assay. VEGF protein expression was measured by western blotting and the microvessel density by immunohistochemical staining., Results: The total psoriasis area and severity index scores in the moderate- and high-dose thalidomide and acitretin groups decreased significantly (p<0.001 for each), and so were the total Baker's scores in the high-dose thalidomide (p=0.008) and acitretin groups (p=0.021). The mean thickness of the epidermis in the experimental and acitretin groups decreased significantly, respectively (p<0.001 for all); the acitretin group was the thinnest. The cutaneous VEGF protein levels down-expressed significantly in the moderate- and high-dose thalidomide groups (p<0.05 for both), while those in the low-dose thalidomide and acitretin did not (p>0.05 for both). There were no differences for serum VEGF-A levels and the density of microvessels among the positive and experimental groups., Conclusion: Thalidomide can improve the psoriasis-like lesions and inhibit the expression of cutaneous VEGF in imiquimod-induced psoriatic model with dose-dependence, however, it does not alter circulating VEGF-A levels and microvessel density in dermis., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Imiquimod (IMQ)-induced mouse psoriatic model is one of the useful models displaying most of psoriatic features. To compare the modeling efficacy of different IMQ creams, we induced the psoriatic models by topically applying two different brands of IMQ 5% creams to the shaved Balb/c mice skin and assessed the results. Balb/c female mice (n = 24) 8-12 weeks of age were randomly divided into experimental groups A (Likejie), B (Aldara), and control group C (Vaseline); Likejie, Aldara, or Vaseline was topically applied to the back skin for mice in groups A, B, and C, respectively, for six consecutive days. The total psoriasis area and severity index scores of groups A, B, and C were 3.25 ± 1.56, 9.81 ± 0.84, and 0, respectively; the Baker's scores were 2.93 ± 1.07, 6.47 ± 1.50, and 0, respectively; and the epidermis thickness was 49.79 ± 14.16, 85.62 ± 17.55, and 20.04 ± 3.68 µm, respectively. The differences between the three groups in dual were statistically significant (P < 0.005 for the groups in dual). Aldara group showed more characteristic alterations of psoriasiform lesions than that of Likejie both macroscopically and histopathologically. The results suggested that different brands of IMQ creams may result in differential efficacy when performing the IMQ-induced psoriasis mouse models., (© 2016 by the Society for Experimental Biology and Medicine.)

Psoriasis is a chronic skin disease of unknown aetiology but increasing evidence suggests that cutaneous angiogenesis plays an important role. Vascular endothelial growth factor (VEGF) is one of the pro-angiogenic cytokines which is related to the pathogenesis of psoriasis. Our study evaluated the influence of imiquimod (IMQ) on VEGF in IMQ-induced mouse model. Balb/c female mice (n=16) 8-12 weeks of age were randomly divided into an experimental group (5% IMQ cream) and the control group (Vaseline cream). Serum levels of circulating VEGF-A were quantified by enzyme-linked immunosorbent assay. VEGF protein expression in tested skin was measured by western blotting and immunohistochemical staining. The tested skin in the experimental group expressed higher levels of VEGF protein than in the control group (p=0.012); immunohistochemical staining revealed that the cells over-expressing VEGF localized predominantly in the epidermis and vascular endothelium. Circulating VEGF-A levels showed no significant difference between the experimental and control groups (p=0.445). The IMQ-induced mouse psoriatic model showed an upregulation of VEGF in the skin lesions mimicking human psoriasis but the circulating VEGF-A levels showed no difference. This model may be useful to investigate the role of angiogenesis in psoriasis.

Both shingles and psoriasis are common cutaneous diseases. About 25% of the psoriatic patients develop Koebner phenomenon (KP) after various injuries, and in rare instance, KP may occur at the site of healed or healing shingles.We report a 30-year-old man with 7-month history of scalp psoriasis who developed KP at the areas of developing shingles. Cutaneous examination revealed scaly erythematous papules and plaques located on the scalp and forehead, and groups of clustered erythematous papules with silver scales in the dermatome distributed on the right side of chest wall the prior herpes zoster lesions involved. After removal of the scales on the papules, underlying bleeding points were present.The lesions on chest had good response to anti-psoriatic therapies, as the lesions on scalp did. After a year of follow-up, recurrent psoriasis occurred, but the lesions were located only on the scalp, and the areas of prior occurrence of shingles, because of which we considered diagnosis of recurrent psoriasis rather than relapsing KP for the chest lesions.Not only the healing and healed shingles can trigger KP in psoriasis, but also the developing shingles can cause psoriatic KP at the site of herpes zoster lesions.