Kuehn S, Hurst J, Rensinghoff F, Tsai T, Grauthoff S, Satgunarajah Y, Dick H B, Schnichels S, Joachim S C
Experimental Eye Research, Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892 Bochum, Germany.
University Eye Hospital Tübingen, Centre for Ophthalmology, Elfriede-Aulhorn-Str. 7, 72076, Tübingen, Germany.
Exp Eye Res. 2017 Feb;155:107-120. doi: 10.1016/j.exer.2017.01.003. Epub 2017 Jan 12.
In order to understand the pathological processes of retinal diseases, experimental models are necessary. Cobalt, as part of the vitamin B12 complex, is important for neuronal integrity. However, it is known that high quantities of cobalt induce cytotoxic mechanisms via hypoxia mimicry. Therefore, we tested the degenerative effect of cobalt chloride (CoCl) on neurons and microglia in a porcine retina organ culture model. Organotypic cultures of porcine retinas were cultured and treated with different concentrations of CoCl (0, 100, 300 and 500 μM) for 48 h. After four and eight days, CoCl induced a strong degeneration of the porcine retina, starting at 300 μM. A loss of retinal ganglion cells (RGCs, Brn-3a), amacrine cells (calretinin) and bipolar cells (PKCα) was observed. Additionally, a high expression of hypoxia induced factor-1a (HIF-1a) and heat shock protein 70 (HSP70) was noted at both points in time. Also, the Caspase 3 protein was activated and P21 expression was induced. However, only at day four, the Bax/Bcl-2 ratio was increased. The effect of CoCl was not restricted to neurons. CoCl concentrations reduced the microglia amount (Iba1) and activity (Iba1 + Fc-Receptor) at both points in time. These damaging effects on microglia were surprising, since CoCl causes hypoxia and a pro-inflammatory environment. However, high concentrations of CoCl also seem to be toxic to these cells. Similar degenerative mechanisms as in comparison to retinal ischemia animal models were observed. In summary, an effective and reproducible hypoxia-mimicking organotypic model for retinal degeneration was established, which is easy to handle and ready for drug studies.
为了了解视网膜疾病的病理过程，实验模型是必要的。钴作为维生素B12复合物的一部分，对神经元完整性很重要。然而，已知高剂量的钴会通过模拟缺氧诱导细胞毒性机制。因此，我们在猪视网膜器官培养模型中测试了氯化钴（CoCl）对神经元和小胶质细胞的退行性影响。培养猪视网膜的器官型培养物，并用不同浓度的CoCl（0、100、300和500 μM）处理48小时。在四天和八天后，CoCl从300 μM开始诱导猪视网膜强烈退变。观察到视网膜神经节细胞（RGCs，Brn-3a）、无长突细胞（钙视网膜蛋白）和双极细胞（PKCα）的丢失。此外，在两个时间点均观察到缺氧诱导因子-1a（HIF-1a）和热休克蛋白70（HSP70）的高表达。同时，半胱天冬酶3蛋白被激活，P21表达被诱导。然而，仅在第四天，Bax/Bcl-2比值增加。CoCl的作用不仅限于神经元。CoCl浓度在两个时间点均降低了小胶质细胞数量（Iba1）和活性（Iba1 + Fc受体）。对小胶质细胞的这些破坏作用令人惊讶，因为CoCl会导致缺氧和促炎环境。然而，高浓度的CoCl似乎对这些细胞也有毒性。观察到与视网膜缺血动物模型相比类似的退行性机制。总之，建立了一种有效且可重复的模拟缺氧的视网膜退变器官型模型，该模型易于操作，可用于药物研究。
