甲状旁腺素抑制角质形成细胞增殖与调控PTCHD1及SMO通路关系研究

Our research team and foreign studies have shown that parathyroid hormone can improve psoriatic lesions and inhibit the proliferation of keratinocytes. It is possible to treat psoriasis. But the mechanism is unknown. We found that the drug can cause the down-regulated PTCHD1 and up-regulated SMO. Therefore, it is suggested that the inhibitory effect of parathyroid hormone on the proliferation of keratinocytes may be related to the regulation of PTCHD1 and SMO. On the basis of the previous project, the PTCHD1 and SMO gene silence and over expression were induced by RNA interference and plasmid transfection respectively. Reversed PTCHD1 and SMO were induced to observe whether the inhibition was relieved. Finally, after interfering with the gene, the intervention of parathyroid hormone was added to observe whether the cell proliferation was consistent with that in the untreated group. At the same time, explore the relationship between PTCHD1 and SMO and the changes of downstream target genes. To determine whether parathyroid hormone inhibited keratinocyte proliferation is relationship with the regulation of PTCHD1 and SMO pathway. The aim of this study is to develop new drugs for the treatment of psoriasis and search for drug targets.

本课题组和国外研究显示，甲状旁腺素可改善银屑病皮损、抑制角质形成细胞增殖，有望治疗银屑病，但机制不明。通过基因芯片我们发现，该药引起角质形成细胞PTCHD1下调、SMO上调。因此推测甲状旁腺素抑制角质形成细胞增殖可能与调控PTCHD1及SMO有关。本项目拟在前期基础上，应用RNA干扰、质粒转染等技术分别诱导PTCHD1与SMO基因沉默与过表达，观察是否可以模拟药物抑制角质形成细胞增殖。再反向诱导PTCHD1与SMO，观察抑制作用是否解除。最后再次干扰基因后，加入甲状旁腺素干预，观察用药与未用药组细胞增殖是否一致。同时探索用药后PTCHD1与SMO两者作用关系，及通路下游靶基因的变化情况。旨在明确甲状旁腺素抑制角质形成细胞增殖是否与调控PTCHD1及SMO通路有关，及两者的关系。为研制和开发治疗银屑病新药，寻找药物靶标，奠定实验和理论依据。

【背景】本课题组和国外研究显示，甲状旁腺素可改善银屑病皮损、抑制角质形成细胞增殖，有望治疗银屑病，但机制不明。通过基因芯片我们发现，该药引起角质形成细胞PTCHD1下调、SMO上调。因此推测甲状旁腺素抑制角质形成细胞增殖可能与调控PTCHD1及SMO有关。.【研究内容】本项目在前期基础上，应用RNA干扰、质粒转染等技术分别诱导PTCHD1与SMO基因沉默与过表达，观察是否可以模拟药物抑制角质形成细胞增殖。再反向诱导PTCHD1与SMO，观察抑制作用是否解除。最后再次干扰基因后，加入甲状旁腺素干预，观察用药与未用药组细胞增殖是否一致。同时探索用药后PTCHD1与SMO两者作用关系，及通路下游靶基因的变化情况。.【重要结果和关键数据】.1.rhPTH（1-34）可抑制角质形成细胞增殖。.2.PTCHD1与重组人甲状旁腺素（1-34）抑制角质形成细胞增殖相关。其作用机制与我们提出的设想基本一致。诱导其过表达后，细胞增殖活跃，标志细胞周期的相关蛋白表达一致。再加入重组人甲状旁腺素（1-34）后细胞增殖被抑制。.3.SMO与重组人甲状旁腺素（1-34）抑制角质形成细胞增殖的关系不确定。诱导其沉默后，细胞增殖抑制，标志细胞周期的相关蛋白表达相反。再加入重组人甲状旁腺素（1-34）后细胞增殖仍被抑制，细胞周期与之相反，呈现出增殖活跃的表现。.4.在重组人甲状旁腺素（1-34）调节角质形成细胞增殖的过程中PTCHD1与SMO作用相反。.【科学意义】rhPTH(1-34)具有治疗银屑病的潜力，但机制不明。本项研究证实rhPTH（1-34）是通过下调PTCHD1抑制角质形成细胞增殖。PTCHD1是Hh信号转导途径的重要环节，通过激活下游因子，启动多条目的基因，调控细胞增殖与分化。该项研究揭示rhPTH(1-34)治疗银屑病与调控Hh信号转导途径中的PTCHD1有关，为研发银屑病新药，奠定理论依据。