背景:老化引起的睫状肌功能下降是导致老年人视觉调节缺陷的重要因素。通过这项研究,我们提供了睫状肌老化和氧化应激之间的相互作用的创新研究。
方法:用三色豚鼠进行体内实验,用原代豚鼠睫状平滑肌细胞进行体外实验。
结果:我们使用生物信息学丰富了与肌肉-衰老-叶黄素关系相关的基因,包括核因子-红系2相关因子-2(Nrf2),谷胱甘肽过氧化物酶(GPx)基因家族,超氧化物歧化酶(SOD)基因家族,NAD(P)H:醌氧化还原酶1(NQO1)和血红素加氧酶-1(HO-1)。给老年豚鼠灌胃后,叶黄素可降低衰老睫状肌中的活性氧(ROS)和P21水平;叶黄素可减少屈光不正并恢复眼睛的调节。此外,叶黄素增加GPx,SOD,血清过氧化氢酶(CAT)水平;叶黄素增加睫状体GPx和CAT水平。叶黄素调节Nrf2、Kelch样ECH相关蛋白1(Keap1)、和衰老睫状体中的下游蛋白质。同样,豚鼠睫状肌细胞衰老与氧化应激有关。体外,100μM叶黄素逆转了800μMH2O2引起的损伤;它减少了衰老相关的β-半乳糖苷酶(SA-β-Gal)和ROS活性,细胞凋亡和细胞迁移。此外,叶黄素增加平滑肌收缩蛋白的表达。叶黄素还增长了Nrf2、GPx2、NQO1和HO-1的表达,下降了Keap1的表达。Nrf2活性的降低导致叶黄素激活细胞中抗氧化酶的能力降低,从而降低其对细胞衰老的抑制作用。
结论:叶黄素通过调节Keap1/Nrf2/抗氧化反应元件途径提高了体内和体外衰老睫状肌的抗氧化应激能力。我们已经创新性地证明了叶黄素逆转与年龄相关的睫状肌收缩和舒张功能缺陷的分子药理机制。
BACKGROUND: Aging-induced decline in ciliary muscle function is an important factor in visual accommodative deficits in elderly adults. With this study, we provide an innovative investigation of the interaction between ciliary muscle aging and oxidative stress.
METHODS: Tricolor guinea pigs were used for the experiments in vivo and primary guinea pig ciliary smooth muscle cells were used for the experiments in vitro.
RESULTS: We enriched for genes associated with muscle-aging-lutein relationship using bioinformatics, including Nuclear factor-erythroid 2-related factor-2 (Nrf2), Glutathione Peroxidase (GPx) gene family, Superoxide Dismutase (SOD) gene family, NAD(P)H: Quinone Oxidoreductase 1 (NQO1) and Heme Oxygenase-1 (HO-1). After gavage to aged guinea pigs, lutein reduced Reactive Oxygen Species (ROS) and P21 levels in senescent ciliary muscle;
lutein decreased refractive error and restored accommodation of the eye. In addition,
lutein increased GPx, SOD, and Catalase (CAT) levels in serum;
lutein increased GPx and CAT levels in ciliary bodies.
Lutein regulated the expression of proteins such as Nrf2, Kelch-like ECH-associated protein 1 (Keap1), and downstream proteins in senescent ciliary bodies. Similarly, guinea pig ciliary muscle cell senescence was associated with oxidative stress. In vitro, 100 μM lutein reversed the damage caused by 800 μM H2O2; it reduced Senescence-Associated β-galactosidase (SA-β-Gal) and ROS activites, cell apoptosis and cell migration. Also,
lutein increased the expression of smooth muscle contractile proteins.
Lutein also increased the expression of Nrf2, GPx2, NQO1 and HO-1, decreased the expression of Keap1. A reduction in Nrf2 activity led to a reduction in the ability of lutein to activate antioxidant enzymes in the cells, thus reducing its inhibitory effect on cell senescence.
CONCLUSIONS: lutein improved resistance to oxidative stress in senescent ciliary muscle in vivo and in vitro by regulating the Keap1/Nrf2/Antioxidant Response Element pathway. We have innovatively demonstrated the molecular pharmacological mechanism by which lutein reverse age-related ciliary muscle systolic and diastolic deficits.