Mechanisms of Chemically Induced Photosensitivity

化学诱导光敏性的机制

基本信息

批准号：
7593921
负责人：
COLIN CHIGNELL
金额：
$ 146.07万
依托单位：
NATIONAL INSTITUTE OF ENVIRONMENTAL HEALTH SCIENCES
依托单位国家：
美国
项目类别：
财政年份：
资助国家：
美国
起止时间：
至
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/7593921
关键词：
Alkaloids Amphiregulin Attenuated Berberine Biological Assay Blocking Antibodies Cell Cycle Progression Cell Proliferation Cells Chemopreventive Agent Cyclin D1 Development Dominant-Negative Mutation Dose Environmental Hazards Epidermal Growth Factor Receptor Flame Retardants GM 6001 Goldenseal Human Hypericin Hypericum perforatum Incubated Light Lipids Maps Mediating Metalloproteases Mitogen-Activated Protein Kinase Inhibitor Molecular Oxygen PI3K/AKT Patients Photosensitivity Photosensitizing Agents Plasma Process Proto-Oncogene Proteins c-akt Research Project Grants Role Signal Pathway Singlet Oxygen Skin Small Interfering RNA Smith-Lemli-Opitz Syndrome Structure of retinal pigment epithelium Superoxides Techniques Therapeutic Therapeutic Effect Triethylenetetramine UVA induced Visible Radiation inhibitor/antagonist interest irradiation keratinocyte kinase inhibitor lens oxidation tetrabromobisphenol A

项目摘要

We have demonstrated that a low, non-lethal dose of UVA exposure induces dose-dependent cell cycle progression in human HaCaT keratinocytes. We found that UVA induced cyclin D1 accumulation, while siRNA knockdown of cyclin D1 blocked the UVA-induced cell cycle progression, indicating that this process is mediated by cyclin D1. UVA irradiation also induced AKT activation; when cells were incubated with PI3K/AKT inhibitor or infected with dominant negative AKT, cell cycle progression and proliferation were inhibited, suggesting that AKT activation is involved in UVA-induced cell cycle progression. In contrast, ERK was not activated by UVA exposure; incubation with ERK/MAPK inhibitor had no effect on UVA-induced cell cycle progression. Activation of EGFR was observed after UVA exposure. EGFR kinase inhibitor AG1478 attenuated UVA-induced cell cycle progression, indicating the involvement of EGFR activation. Furthermore, metalloprotease inhibitor GM6001 blocked UVA-induced cell cycle progression, and siRNA knockdown of ADAM17 had a similar inhibitory effect, demonstrating that ADAM17 has a role in mediating the UVA-induced cell cycle progression. Consistent with the role of ADAM17, antibody blocking amphiregulin attenuated UVA-induced cell cycle progression, implying the involvement of amphiregulin. Identification of these signaling pathways in UVA-induced cell proliferation will facilitate the development of efficient and safe chemopreventive and therapeutic strategies for skin cancer.We have identified the skin lipid cholesta-5,7,9(11)-trien-3 beta-ol (9-DDHC) as the putative agent responsible for UVA-induced skin photosensitivity in Smith-Lemli-Opitz syndrome patients. 9-DDHC generates singlet oxygen and superoxide upon UVA irradiation, is phototoxic to keratinocytes and is found in higher concentrations in plasma from UVA sensitive patients. We have demonstrated that berberine, the main alkaloid present in Goldenseal, is phototoxic to human retinal pigment epithelial cells and lens cells, while hypericin, found in St Johns Wort, is photototoxic to retinal pigment epithelial cells. We have successfully mapped the intracellular spatial localization of singlet oxygen in keratinocytes using the immuno-spin assay technique. Finally, We have found that the flame retardant 3,3,5,5-tetrabromobisphenol A (TBBPA) is subject to photosensitized oxidation involving singlet molecular oxygen. Wide use of flame retardants such as TBBPA can pose an environmental hazard and it is of interest to investigate how they may degrade.

我们已经证明，低、非致命剂量的 UVA 暴露会诱导人 HaCaT 角质形成细胞发生剂量依赖性细胞周期进展。我们发现UVA诱导cyclin D1积累，而cyclin D1的siRNA敲低则阻断了UVA诱导的细胞周期进程，表明该过程是由cyclin D1介导的。 UVA 照射也会诱导 AKT 激活；当细胞与 PI3K/AKT 抑制剂一起孵育或感染显性失活 AKT 时，细胞周期进程和增殖受到抑制，表明 AKT 激活参与了 UVA 诱导的细胞周期进程。相反，ERK 不会被 UVA 暴露激活；与 ERK/MAPK 抑制剂一起孵育对 UVA 诱导的细胞周期进程没有影响。 UVA 暴露后观察到 EGFR 的激活。 EGFR 激酶抑制剂 AG1478 减弱 UVA 诱导的细胞周期进程，表明 EGFR 激活参与其中。此外，金属蛋白酶抑制剂 GM6001 阻断 UVA 诱导的细胞周期进程，ADAM17 的 siRNA 敲低也具有类似的抑制作用，表明 ADAM17 在介导 UVA 诱导的细胞周期进程中发挥作用。与 ADAM17 的作用一致，阻断双调蛋白的抗体可减弱 UVA 诱导的细胞周期进程，这表明双调蛋白参与其中。鉴定 UVA 诱导的细胞增殖中的这些信号通路将有助于开发有效且安全的皮肤癌化学预防和治疗策略。我们已经鉴定出皮肤脂质胆汁酸-5,7,9(11)-trien-3 beta-ol (9-DDHC) 被认为是导致 Smith-Lemli-Opitz 综合征患者 UVA 诱导皮肤光敏性的推定因素。 9-DDHC 在 UVA 照射下产生单线态氧和超氧化物，对角质形成细胞具有光毒性，并且在 UVA 敏感患者的血浆中浓度较高。我们已经证明，白毛茛中存在的主要生物碱小檗碱对人视网膜色素上皮细胞和晶状体细胞具有光毒性，而圣约翰草中发现的金丝桃素对视网膜色素上皮细胞具有光毒性。我们使用免疫旋转测定技术成功地绘制了角质形成细胞中单线态氧的细胞内空间定位。最后，我们发现阻燃剂3,3,5,5-四溴双酚A（TBBPA）会发生涉及单线态分子氧的光敏氧化。广泛使用 TBBPA 等阻燃剂可能会对环境造成危害，因此有必要研究它们如何降解。