Zhou Jia, Feng Jun-Yi, Wang Qian, Shang Jing
New Drug Screening Center, China Pharmaceutical University, Nanjing 210009, PR China; School of Pharmaceutical Science, Jiangnan University, Wuxi 214122, PR China.
New Drug Screening Center, China Pharmaceutical University, Nanjing 210009, PR China.
Cytokine. 2015 Jul;74(1):137-44. doi: 10.1016/j.cyto.2015.01.034. Epub 2015 May 14.
Skin is the largest organ in human body and works as biologically active barrier to provide critical preservation of body homeostasis. The skin is highly innervated by a plenitude of nerve fiber subpopulations, each carrying one or more neuronal mediators. Melanocyte itself also intimately contact with nerve fibers to form 'synaptic-like structure' and its functions may be directly regulated by the mediators contained in terminals of intra-epidermal nerve fibers. Clinical and biochemical studies have suggested that calcitonin gene-related peptide (CGRP) is involved in vitiligo skin. The present study was designed to investigate the effect of CGRP on epidermal melanocytes. After treatment with CGRP ranging from 0 to 500 ng/mL for 48 h, tyrosinase activity and melanogenesis were with little changes compared to treatment with medium only in B16F10 cells. Treatment with 500 ng/mL of CGRP cooperates with substance P (SP) (0.1-10 nM) to decrease tyrosinase activity and decrease melanin biosynthesis in B16F10 cells in a concentration-dependent manner. Furthermore, CGRP (8-37) antagonizes the synergistic effect of CGRP. The effect of CGRP on the cell apoptosis was examined. Treatments with 0-500 ng/mL of CGRP for 24 h, the expression levels of cleaved caspase-3, total caspase-3, cleaved caspase-9 and total caspase-9 were increased in a concentration-dependent manner. And 500 ng/mL of CGRP induced B16F10 cell apoptosis showed by TUNEL assay. In addition, Bax expression was up-regulated and Bcl-2 down-regulated in response to CGRP treatment. Hence, the Bax/Bcl-2 ratio was significantly increased. These in vitro observations indicate the pro-apoptotic impact of CGRP on B16F10 cell.
皮肤是人体最大的器官，作为生物活性屏障发挥作用，对维持身体内环境稳态至关重要。皮肤由大量神经纤维亚群高度支配，每个亚群携带一种或多种神经介质。黑素细胞自身也与神经纤维紧密接触形成“突触样结构”，其功能可能直接受表皮内神经纤维末梢所含介质的调节。临床和生化研究表明，降钙素基因相关肽（CGRP）与白癜风皮肤有关。本研究旨在探讨CGRP对表皮黑素细胞的影响。用0至500 ng/mL的CGRP处理48小时后，与仅用培养基处理相比，B16F10细胞中的酪氨酸酶活性和黑素生成几乎没有变化。用500 ng/mL的CGRP与P物质（SP）（0.1 - 10 nM）联合处理，可使B16F10细胞中的酪氨酸酶活性降低，并以浓度依赖的方式减少黑色素生物合成。此外，CGRP（8 - 37）可拮抗CGRP的协同作用。检测了CGRP对细胞凋亡的影响。用0至500 ng/mL的CGRP处理24小时后，裂解的半胱天冬酶-3、总半胱天冬酶-3、裂解的半胱天冬酶-9和总半胱天冬酶-9的表达水平呈浓度依赖性增加。TUNEL检测显示500 ng/mL的CGRP诱导B16F10细胞凋亡。此外，响应CGRP处理，Bax表达上调，Bcl-2表达下调。因此，Bax/Bcl-2比值显著增加。这些体外观察结果表明CGRP对B16F10细胞具有促凋亡作用。
