Delphinidin: A Novel Agent For Treatment Of Psoriasis

描述(申请人提供)：银屑病的特征是角质形成细胞过度增殖、颗粒层丢失和角化旁分化。Caspase-14是一个非凋亡性的caspase家族成员，其在表皮中的表达仅限于基底层以上，与终末分化相关。在正常皮肤中，caspase-14在整个基底层的细胞质和细胞核中都能检测到。然而，在以缺乏核破坏为特征的银屑病皮肤角化旁区域，caspase-14的表达下调。上调caspase-14表达的策略可能构成对包括牛皮癣在内的角化不全疾病的新的治疗贡献。诱导表皮角质形成细胞分化的药物可能对牛皮癣有治疗作用，也可能在伤口愈合和其他过度增殖的皮肤疾病中有用。因此，找出一种自然产生的补充和替代医学方法，并使用一种诱导表皮角质形成细胞分化而不诱导细胞凋亡的试剂，是一个非常理想的目标。飞雀素是有色水果和蔬菜中的主要花青素，具有很强的抗氧化活性。最近，我们发现在SKH-1无毛小鼠皮肤中，局部应用Delphinidin可以抑制紫外线B介导的DNA损伤和TUNEL阳性细胞的形成。然而，还没有研究考察Delphinin治疗对正常人角质形成细胞功能的影响。我们未发表的初步研究值得注意的是，我们已经证明了飞虱诱导正常人表皮角质形成细胞中前天冬氨酸氨基转移酶-14蛋白和mRNA的表达。此外，我们还发现，总蛋白和转谷氨酰胺酶-1的蛋白和mRNA表达显著增加。值得注意的是，在相同的处理条件下，Delphinidin不会导致细胞凋亡。这种显著的差异构成了这一应用的基础，该应用旨在研究Delphinidin在体外人类重组皮肤模型系统和体内临床前环境中对角质形成细胞分化的影响。在这项应用中需要检验的中心假说是“Delphinidin将通过诱导caspase-14和其他早期和晚期分化标记的表达以及通过抑制细胞增殖而不诱导细胞凋亡来减少银屑病样皮损的病理标记”。为了验证我们的假设，提出了以下具体目标：(1)研究Delphinidin治疗是否增加了角质形成细胞分化标记物在体外三维人类重组皮肤中的分布和表达水平，作为一个允许表皮完全分化的实验模型系统；(2)利用片状皮肤(FSN/FSN)小鼠和片状皮肤(FSN/FSN)caspase14-/小鼠，检测局部应用Delphinidin对银屑病样皮损病理标记物的影响。将进行研究，以确定caspase-14的表达是否与表皮病理症状的减轻有关。 公共卫生相关性：本申请旨在定义一种存在于有色水果和蔬菜中的新制剂Delphinidin，用于治疗牛皮癣，也可能用于伤口愈合和其他增生性皮肤病。

DESCRIPTION (provided by applicant): Psoriasis is characterized by keratinocyte hyperproliferation, loss of granular layer and parakeratotic differentiation. Caspase-14 is a nonapoptotic caspase family member whose expression in the epidermis is confined to the suprabasal layers, and is associated with terminal differentiation. In normal skin, caspase-14 is detected in the cytoplasm and nuclei throughout the suprabasal layers. However, in the parakeratotic regions of psoriatic skin, which are characterized by the lack of nuclear destruction, caspase-14 expression is down-regulated. Strategies to upregulate caspase-14 expression may constitute a novel therapeutic contribution to diseases involving parakeratosis, including psoriasis. Agents that lead to differentiation of epidermal keratinocytes may have therapeutic effects against psoriasis and could also be useful in wound healing and other hyperproliferative skin disorders. Thus, identifying a naturally occurring Complimentary and Alternative Medicine approach with a agent that induces differentiation of epidermal keratinocytes without inducing apoptosis is a highly desirable goal. Delphinidin, a major anthocyanidin in pigmented fruits and vegetables, possesses potent antioxidant activity. Recently, we have shown that topical application of delphinidin inhibited ultraviolet B-mediated formation of DNA damage and TUNEL-positive cells in SKH-1 hairless mouse skin. However, no studies have examined the impact ofdelphinidin treatment on the function of normal human keratinocytes. Our preliminary unpublished studies are noteworthy where we have demonstrated that delphinidin induces procaspase-14 protein and mRNA expression in normal human epidermal keratinocytes. We also found a significant increase in the protein and mRNA expression of involucrin and transglutaminase-1. It is noteworthy that delphinidin under identical treatment conditions did not result in induction of apoptosis. This remarkable distinction forms the basis of this application which is designed to investigate the effect of delphinidin on keratinocyte differentiation both in in vitro human reconstituted skin model system and in preclinical in vivo settings. The central hypothesis to be tested in this application is that "delphinidin will reduce the pathological markers of psoriasiform lesions by inducing the expression of caspase-14, and other markers of early and late differentiation and by suppressing cell proliferation without inducing apoptosis". To test our hypothesis, the following specific aims are proposed: (1) To investigate whether delphinidin treatment increases the distribution and expression level of keratinocyte differentiation markers in in vitro three- dimensional human reconstituted skin as an experimental model system that allow complete epidermal differentiation, and (2) To examine the effect of topical application of delphinidin on pathological markers of psoriasiform lesions under in vivo situation employing flaky skin (fsn/fsn) mice and flaky skin (fsn/fsn) caspase 14-/- mice. Studies will be conducted to determine whether caspase- 14 expression is associated with reduced symptoms of epidermal pathology. PUBLIC HEALTH RELEVANCE: This application intends to define a novel agent delphinidin present in pigmented fruits and vegetables for the treatment of psoriasis and could also be useful in wound healing and other hyperproliferative skin disorders.