Mechanisms of Chemically Induced Photosensitivity

化学诱导光敏性的机制

• 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
• 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

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，低剂量、非致命性的UVA照射可诱导人HaCaT角质形成细胞发生剂量依赖性的细胞周期进展。我们发现UVA诱导细胞周期蛋白D1的积聚，而抑制细胞周期蛋白D1的siRNA抑制了UVA诱导的细胞周期进程，表明这一过程是由细胞周期蛋白D1介导的。UVA照射也可诱导AKT激活，当细胞与PI3K/AKT抑制剂共同孵育或感染显性阴性AKT时，细胞周期进程和增殖受到抑制，提示AKT激活参与了UVA诱导的细胞周期进程。相反，UVA不能激活ERK；与ERK/MAPK抑制剂孵育对UVA诱导的细胞周期进程没有影响。UVA照射后可观察到EGFR的活化。EGFR激酶抑制剂AG1478可抑制UVA诱导的细胞周期进程，表明EGFR参与了细胞周期的激活。此外，金属蛋白酶抑制剂GM6001阻断了UVA诱导的细胞周期进程，下调ADAM17的siRNA也具有类似的抑制作用，表明ADAM17在UVA诱导的细胞周期进程中具有中介作用。与ADAM17的作用一致，抗体阻断双调节蛋白可减弱UVA诱导的细胞周期进程，暗示双调节蛋白参与其中。识别UVA诱导的细胞增殖中的这些信号通路将有助于开发有效和安全的皮肤癌化学预防和治疗策略。我们已经确定皮肤脂质Cholesta-5，7，9(11)-Trien-3β-ol(9-DDHC)是导致Smith-Lemli-Opitz综合征患者UVA诱导的皮肤光敏的可能因素。9-DDHC在UVA照射下产生单线态氧和超氧化物，对角质形成细胞有光毒性，在UVA敏感患者的血浆中发现较高浓度的9-DDHC。我们已经证明，黄花中存在的主要生物碱黄连素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。我们已经使用免疫自旋分析技术成功地定位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)发生了单分子氧的光敏氧化。广泛使用阻燃剂，如TBBPA，可能会对环境造成危害，调查它们如何降解是有意义的。