Hass Daniel T, Pandey Kriti, Engel Abbi, Horton Noah, Robbings Brian M, Lim Rayne, Sadilek Martin, Zhang Qitao, Autterson Gillian A, Miller Jason M L, Chao Jennifer R, Hurley James B
bioRxiv. 2023 Nov 8:2023.11.07.566117. doi: 10.1101/2023.11.07.566117.
In age-related macular degeneration (AMD) and Sorsby's fundus dystrophy (SFD), lipid-rich deposits known as drusen accumulate under the retinal pigment epithelium (RPE). Drusen may contribute to photoreceptor and RPE degeneration in AMD and SFD. We hypothesize that stimulating β-oxidation in RPE will reduce drusen accumulation. Inhibitors of acetyl-CoA carboxylase (ACC) stimulate β-oxidation and diminish lipid accumulation in fatty liver disease. In this report we test the hypothesis that an ACC inhibitor, Firsocostat, limits the accumulation of lipid deposits in cultured RPE cells.
We probed metabolism and cellular function in mouse RPE-choroid, human fetal- derived RPE cells, and induced pluripotent stem cell-derived RPE cells. We used C6-glucose and C16-palmitate to determine the effects of Firsocostat on glycolytic, Krebs cycle, and fatty acid metabolism. C labeling of metabolites in these pathways were analyzed using gas chromatography-linked mass spectrometry. We quantified ApoE and VEGF release using enzyme-linked immunosorbent assays. Immunostaining of sectioned RPE was used to visualize ApoE deposits. RPE function was assessed by measuring the trans-epithelial electrical resistance (TEER).
ACC inhibition with Firsocostat increases fatty acid oxidation and remodels lipid composition, glycolytic metabolism, lipoprotein release, and enhances TEER. When human serum is used to induce sub-RPE lipoprotein accumulation, fewer lipoproteins accumulate with Firsocostat. In a culture model of Sorsby's fundus dystrophy, Firsocostat also stimulates fatty acid oxidation, improves morphology, and increases TEER.
Firsocostat remodels intracellular metabolism and improves RPE resilience to serum-induced lipid deposition. This effect of ACC inhibition suggests that it could be an effective strategy for diminishing drusen accumulation in the eyes of patients with AMD.
在年龄相关性黄斑变性（AMD）和索斯比眼底营养不良（SFD）中，视网膜色素上皮（RPE）下会积聚富含脂质的沉积物，即玻璃膜疣。玻璃膜疣可能导致AMD和SFD中的光感受器和RPE变性。我们假设刺激RPE中的β-氧化将减少玻璃膜疣的积聚。乙酰辅酶A羧化酶（ACC）抑制剂可刺激β-氧化并减少脂肪肝疾病中的脂质积聚。在本报告中，我们测试了ACC抑制剂非索非那定限制培养的RPE细胞中脂质沉积物积聚的假设。
我们探究了小鼠RPE-脉络膜、人胎儿来源的RPE细胞和诱导多能干细胞来源的RPE细胞中的代谢和细胞功能。我们使用C6-葡萄糖和C16-棕榈酸来确定非索非那定对糖酵解、三羧酸循环和脂肪酸代谢的影响。使用气相色谱-质谱联用技术分析这些途径中代谢物的C标记。我们使用酶联免疫吸附测定法定量ApoE和VEGF的释放。对RPE切片进行免疫染色以观察ApoE沉积物。通过测量跨上皮电阻（TEER）评估RPE功能。
非索非那定抑制ACC可增加脂肪酸氧化，重塑脂质组成、糖酵解代谢、脂蛋白释放，并增强TEER。当使用人血清诱导RPE下脂蛋白积聚时，使用非索非那定后积聚的脂蛋白较少。在索斯比眼底营养不良的培养模型中，非索非那定还可刺激脂肪酸氧化，改善形态，并增加TEER。
非索非那定重塑细胞内代谢，提高RPE对血清诱导脂质沉积的耐受性。ACC抑制的这种作用表明，它可能是减少AMD患者眼中玻璃膜疣积聚的有效策略。
