Department of Ophthalmology, Sue Anschutz-Rodgers Eye Center, School of Medicine, Aurora, CO 80045, USA.
Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA.
Int J Mol Sci. 2023 Jan 22;24(3):2196. doi: 10.3390/ijms24032196.
With aging, human lenses lose the ability to focus on nearby objects due to decreases in accommodative ability, a condition known as presbyopia. An increase in stiffness or decrease in lens elasticity due to protein aggregation and insolubilization are the primary reasons for presbyopia. In this study, we tested aggrelyte-1 (,-diacetyl glutathione diethyl ester) for its ability to promote protein solubility and decrease the stiffness of lenses through its dual property of lysine acetylation and disulfide reduction. Treatment of water-insoluble proteins from aged human lenses (58-75 years) with aggrelyte-1 significantly increased the solubility of those proteins. A control compound that did not contain the S-acetyl group (aggrelyte-1C) was substantially less efficient in solubilizing water-insoluble proteins. Aggrelyte-1-treated solubilized protein had significant amounts of acetyllysine, as measured by Western blotting and LC-MS/MS. Aggrelytes increased the protein-free thiol content in the solubilized protein. Aged mouse (7 months) and human (44-66 years) lenses treated with aggrelyte-1 showed reduced stiffness accompanied by higher free thiol and acetyllysine levels compared with those treated with aggrelyte-1C or untreated controls. Our results suggested that aggrelyte-1 reduced lens stiffness through acetylation followed by disulfide reduction. This proof-of-concept study paves the way for developing aggrelyte-1 and related compounds to reverse presbyopia.
随着年龄的增长，人类晶状体由于调节能力下降而失去了聚焦近距离物体的能力，这种情况被称为老视。由于蛋白质聚集和不溶性增加导致的刚性增加或晶状体弹性下降是老视的主要原因。在这项研究中，我们测试了 aggrelyte-1（双乙酰谷胱甘肽二乙酯）通过赖氨酸乙酰化和二硫键还原的双重特性促进蛋白质可溶性和降低晶状体刚性的能力。用 aggrelyte-1 处理来自 58-75 岁老年人晶状体的不溶性蛋白质，显著增加了这些蛋白质的可溶性。不含 S-乙酰基的对照化合物（aggrelyte-1C）在溶解不溶性蛋白质方面效率要低得多。aggrelyte-1 处理的可溶性蛋白质中含有大量乙酰赖氨酸，通过 Western blot 和 LC-MS/MS 测定。aggrelytes 增加了可溶性蛋白质中的无蛋白巯基含量。与用 aggrelyte-1C 或未处理的对照处理相比，用 aggrelyte-1 处理的老年小鼠（7 个月）和人（44-66 岁）晶状体的刚性降低，同时具有更高的游离巯基和乙酰赖氨酸水平。我们的结果表明，aggrelyte-1 通过乙酰化随后二硫键还原降低了晶状体的刚性。这项概念验证研究为开发 aggrelyte-1 和相关化合物以逆转老视铺平了道路。
