Caspase-14 and the Treatment of Psoriasis

描述（由申请人提供）：牛皮癣是一种慢性皮肤病，其特征是炎症，鳞状和经常毁容的皮肤病变。皮肤病变表现为增生和终末分化改变，导致角化不全和脱屑。caspase -14是caspase家族的一种非凋亡成员，参与终末分化，在响应屏障破坏和正常角质细胞形成时加速角质化是必不可少的。新出现的数据和我们令人信服的初步研究表明，与来自同一个体和正常对照个体的非病变皮肤的相应样本相比，人类银屑病皮损中caspase-14的表达明显下调。因此，确定具有诱导终末分化和抑制过度增殖能力的天然抗炎剂可能对银屑病的治疗有用。飞燕草苷是一种主要的花青素，丰富存在于色素水果和蔬菜中，具有抗炎和抗增殖活性。我们的初步未发表的研究值得注意，我们已经证明，飞鸽苷处理诱导正常人表皮角质形成细胞（NHEK）中procaspase-14的蛋白和mRNA表达。Delphinidin还诱导caspase-14加工成具有催化活性的亚基p10和p20。我们还发现，在飞鸽苷处理的NHEK中，天花素和谷氨酰胺转肽类酶-1的蛋白和mRNA表达显著增加。此外，飞鸽素对NHEK的处理增加了AP-1亚基和NF-:B亚基p50和RelB的蛋白表达。重要的是，在相同的处理条件下，飞燕草苷没有诱导细胞凋亡。这一显著的区别构成了本提案的基础，该提案旨在研究飞燕草苷在体外人重建皮肤模型和临床前体内环境中对角质细胞分化和过度增殖的影响。本提案需要验证的假设是“delphinidin通过诱导caspase-14的表达和抑制细胞增殖而不诱导细胞凋亡，从而诱导分化和加速角质化，从而降低牛皮癣样病变的严重程度”。为了验证我们的假设，提出了以下具体目标：(i)研究飞飞蓟素是否通过增加三维人重建皮肤模型中caspase-14的表达和加工来加速角质化过程。（ii）研究飞飞蓟素对三维人重建皮肤模型中caspase-14表达、细胞定位和加工的影响是否通过AP-1和NF-:B途径介导。（iii）在体内情况下，通过片状皮肤（fsn/fsn）小鼠和片状皮肤（fsn/fsn） caspase 14-/-小鼠，确定caspase-14是否与飞飞蓟素治疗后表皮病理症状的减轻有关。该提案将确定caspase-14在治疗牛皮癣中的作用，此外还将引起人们对使用飞鸽苷（一种花青素）治疗牛皮癣的关注。

DESCRIPTION (provided by applicant): Psoriasis is a chronic skin disease characterized by inflamed, scaly and frequently disfiguring skin lesions. The skin lesions show hyperproliferation and altered terminal differentiation leading to parakeratosis and desquamation. Caspase-14 is a nonapoptotic caspase family member and is involved in terminal differentiation and is essential for accelerated cornification in response to barrier disruption and for the formation of normal corneocytes. Emerging data and our compelling preliminary studies suggest that caspase-14 expression is substantially down-regulated in human psoriatic lesions compared to corresponding samples from nonlesional skin of the same individuals and from normal control individual. Thus, identifying naturally occurring anti-inflammatory agents which possess the ability to induce terminal differentiation and inhibit hyperproliferation could be useful for the treatment of psoriasis. Delphinidin, a major anthocyanidin abundantly present in pigmented fruits and vegetables, possesses anti-inflammatory and anti-proliferative activities. Our preliminary unpublished studies are noteworthy where we have demonstrated that delphinidin treatment induced the protein and mRNA expression of procaspase-14 in normal human epidermal keratinocytes (NHEK). Delphinidin also induced the processing of caspase-14 into catalytically active subunits p10 and p20. We also found a significant increase in the protein and mRNA expression of involucrin and transglutaminase-1 in delphinidin treated NHEK. Furthermore, delphinidin treatment to NHEK increased the protein expression of AP-1 subunits and NF-:B subunits p50 and RelB. Importantly, delphinidin under identical treatment conditions did not result in induction of apoptosis. This remarkable distinction forms the basis of this proposal which is designed to investigate the effect of delphinidin on keratinocyte differentiation and hyperproliferation both in in vitro human reconstituted skin model and in preclinical in vivo settings. The hypothesis to be tested in this proposal is that "delphinidin will induce differentiation and accelerate cornification that will in turn reduce the severity of psoriasiform lesions by inducing the expression of caspase-14 and suppression of cell proliferation without inducing apoptosis". To test our hypothesis, the following specific aims are proposed: (i) To investigate whether delphinidin treatment accelerates the process of cornification through increased expression and processing of caspase-14 in three-dimensional human reconstituted skin model, (ii) To investigate whether the effect of delphinidin on caspase-14 expression, cellular localization, and processing is mediated through AP-1 and NF-:B pathways in three-dimensional human reconstituted skin model, and (iii) To establish whether caspase-14 is associated with reduced symptoms of epidermal pathology with delphinidin treatment under in vivo situation by employing flaky skin (fsn/fsn) mice and flaky skin (fsn/fsn) caspase 14-/- mice. This proposal will establish the role of caspase-14 for treatment of psoriasis and in addition will draw attention to the use of delphinidin an anthocyanidin for its treatment.