Caspase-14 and the Treatment of Psoriasis

描述（由申请人提供）：银屑病是一种慢性皮肤病，其特征是发炎、鳞状和经常毁容的皮肤病变。皮损表现为过度增生和终末分化改变，导致角化不全和脱屑。Caspase-14是一种非凋亡的caspase家族成员，参与终末分化，对响应屏障破坏的加速角质化和正常角质细胞的形成至关重要。新出现的数据和我们令人信服的初步研究表明，caspase-14的表达在人类银屑病皮损中大幅下调相比，相应的样品，从非皮损的皮肤相同的个人和正常对照个体。因此，鉴定具有诱导终末分化和抑制过度增殖能力的天然存在的抗炎剂可用于治疗银屑病。飞燕草素是一种主要的花青素，广泛存在于有色水果和蔬菜中，具有抗炎和抗增殖活性。我们的初步未发表的研究是值得注意的，我们已经证明，飞燕草素治疗诱导蛋白酶原-14在正常人表皮角质形成细胞（NHEK）的蛋白质和mRNA的表达。飞燕草素还诱导caspase-14加工成催化活性亚基p10和p20。我们还发现在飞燕草素处理的NHEK中，外皮蛋白和转氨酶-1的蛋白和mRNA表达显著增加。飞燕草素处理NHEK后AP-1亚基、NF-：B亚基p50和RelB蛋白表达增加。重要的是，在相同的处理条件下，飞燕草素没有导致诱导细胞凋亡。这种显著的区别形成了该提议的基础，该提议旨在研究飞燕草素在体外人重建皮肤模型和临床前体内环境中对角质形成细胞分化和过度增殖的影响。在该提议中待检验的假设是“飞燕草素将诱导分化并加速角化，这反过来将通过诱导半胱天冬酶-14的表达和抑制细胞增殖而不诱导凋亡来降低银屑病样病变的严重性”。为了检验我们的假设，提出了以下具体目标：（i）研究飞燕草素处理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化过程，（ii）研究飞燕草素对caspase-14表达、细胞定位和加工的影响是否通过AP-1和NF-κ B介导：B途径在三维人类重建皮肤模型中的作用，以及（iii）通过使用脱髓鞘（fsn/fsn）小鼠和脱髓鞘（fsn/fsn）半胱天冬酶14-/-小鼠，确定半胱天冬酶14是否与在体内情况下用飞燕草素治疗的表皮病理学症状减轻相关。这一建议将确立半胱天冬酶-14治疗银屑病的作用，此外还将引起人们对飞燕草色素（一种花青素）治疗银屑病的注意。 公共卫生相关性： 这一建议可能是非常有价值的临床前的方法，为发展新的战略，并确定一种新的代理飞燕草素存在于色素水果和蔬菜治疗银屑病，也可能是有用的，在其他过度增生性皮肤疾病。

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 Our preliminary unpublished studies are noteworthy where we have demonstrated that delphinidin treatment induced the protein and mRNA expression of procaspase-14 in normal human epidermal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. PUBLIC HEALTH RELEVANCE: This proposal may be extremely valuable pre-clinical approach for the development of new strategies and to define a novel agent delphinidin present in pigmented fruits and vegetables for the treatment of psoriasis and could also be useful in other hyperproliferative skin disorders.