Department of Chemistry and Biochemistry, Edison Biotechnology Institute, Ohio University, Athens, OH.
Photochem Photobiol. 2019 Jan;95(1):338-344. doi: 10.1111/php.13006. Epub 2018 Oct 22.
Nitric oxide ( ) plays an important role in the regulation of redox balance in keratinocytes post-UVB exposure. Since endothelial cells releases for a prolonged time post-UVB, we determined whether human umbilical vein endothelial cells (HUVEC) could have an effect on UVB-induced DNA damage and transformation of their adjacent keratinocytes (HaCaT) using a 3D cell co-culturing system. Our data show that the levels of DNA breaks and/or cyclobutane pyrimidine dimer (CPD) along with γH2AX are higher in the co-cultured than in the mono-cultured keratinocytes post-UVB. The level in the co-cultured cells is increased approximately 3-fold more than in mono-cultured HaCaT cells within 1-hour post-UVB but then is reduced quickly in co-cultured HaCaT cells comparing to mono-cultured cells from 6 to 24 h post-UVB. However, the peroxynitrite (ONOO ) level is higher in the co-cultured than in the mono-cultured HaCaT cells in whole period post-UVB. Furthermore, while expression level of inducible nitric oxide synthase (iNOS) is increased, the ratio of coupled/uncoupled eNOS is reduced in co-cultured HaCaT cells compared to mono-cultured HaCaT cells. Finally, the co-cultured cells have a significantly increased transformation efficiency after repeating UVB exposure compared to mono-culture HaCaT cells. Our results suggest that endothelial cells could enhance /ONOO imbalance and promote transformation of adjacent keratinocytes.
一氧化氮（NO）在 UVB 暴露后角质形成细胞氧化还原平衡的调节中发挥重要作用。由于内皮细胞在 UVB 后会释放较长时间的，我们使用 3D 细胞共培养系统来确定人脐静脉内皮细胞（HUVEC）是否会对 UVB 诱导的 DNA 损伤和其相邻角质形成细胞（HaCaT）的转化产生影响。我们的数据表明，与单培养的角质形成细胞相比，共培养的细胞中 DNA 断裂和/或环丁烷嘧啶二聚体（CPD）以及 γH2AX 的水平在 UVB 后更高。在 UVB 后 1 小时内，共培养细胞中的水平比单培养的 HaCaT 细胞增加约 3 倍，但从 6 小时到 24 小时后，共培养的 HaCaT 细胞中的水平迅速降低与单培养细胞相比。然而，在整个 UVB 后时期，共培养的细胞中的过氧亚硝酸盐（ONOO-）水平高于单培养的 HaCaT 细胞。此外，与单培养的 HaCaT 细胞相比，共培养的 HaCaT 细胞中诱导型一氧化氮合酶（iNOS）的表达水平增加，而偶联/非偶联 eNOS 的比例降低。最后，与单培养 HaCaT 细胞相比，重复暴露于 UVB 后，共培养的细胞的转化效率显著增加。我们的结果表明，内皮细胞可能会增强 /ONOO-失衡并促进相邻角质形成细胞的转化。
