Department of Ophthalmology, The First Affiliated Hospital of Xi'an Jiao Tong University, Xi'an, China.
Department of Biophysics, School of Basic Medical Sciences, Institute of Medical Engineering, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China.
J Biochem Mol Toxicol. 2020 Nov;34(11):e22568. doi: 10.1002/jbt.22568. Epub 2020 Jul 14.
Oxidative stress and inflammation have long been considered to be responsible for the development and progression of diabetic retinopathy. On the other hand, rhaponticin (RN) has received scientific attention due to its various pharmacological properties. Keeping all these in view, the present study was performed to investigate the potential protective effects of RN on the retina in diabetic rats. Rats were randomly divided into three groups: control group rats, diabetic group rats, diabetic + RN (20 mg/kg body weight for 28 days through oral route) group rats. RN supplementation to diabetic rats significantly prevent the reduction of final body weight loss, reduced weekly fasting blood glucose levels and HbA1c levels with a significant increase in serum insulin levels. quantitative polymerase chain reaction and immunohistochemical analysis found upregulation of Nrf2, NQO-1, HO-1 and upregulation of Keap1 genes and protein distribution along with significantly reduced levels of malondialdehyde and increased activity of superoxide dismutase, catalase and glutathione peroxidase in RN-treated diabetic rats as compared to diabetic rats. Furthermore, treatment of diabetic rats with RN showed downregulated expression of tumour necrosis factor-α, matrix metalloproteinase-2 and upregulated expression of interleukin-10 (IL-10) and TIMP-1 in the retina. RN treatment decreased nuclear factor kappa-light-chain-enhancer of activated B cells distribution and increased IL-10 protein distribution in the retinae of diabetic rats. In addition, RN treatment ameliorated morphological changes observed in retinae of diabetic rats. Altogether, these results provided clear evidence that treatment of diabetic rats with RN attenuated diabetic retinal changes through its hypoglycaemic, antioxidant and anti-inflammatory effects.
氧化应激和炎症长期以来被认为是糖尿病视网膜病变发展和进展的原因。另一方面，瑞帕昔布（RN）由于其多种药理特性而受到科学关注。鉴于所有这些，本研究旨在研究 RN 对糖尿病大鼠视网膜的潜在保护作用。大鼠随机分为三组：对照组大鼠、糖尿病组大鼠、糖尿病+RN（28 天通过口服途径给予 20mg/kg 体重）组大鼠。RN 补充剂可显著防止糖尿病大鼠体重减轻、每周空腹血糖和 HbA1c 水平降低以及血清胰岛素水平显著升高。定量聚合酶链反应和免疫组织化学分析发现，与糖尿病大鼠相比，Nrf2、NQO-1、HO-1 基因和 Keap1 基因的表达上调以及丙二醛水平降低和超氧化物歧化酶、过氧化氢酶和谷胱甘肽过氧化物酶活性增加。此外，与糖尿病大鼠相比，RN 治疗糖尿病大鼠可下调肿瘤坏死因子-α、基质金属蛋白酶-2 的表达，上调白细胞介素-10（IL-10）和 TIMP-1 的表达。RN 治疗可减少核因子 kappa-轻链增强子活化 B 细胞在糖尿病大鼠视网膜中的分布，并增加 IL-10 蛋白在视网膜中的分布。此外，RN 治疗可改善糖尿病大鼠视网膜观察到的形态变化。总之，这些结果提供了明确的证据，表明用 RN 治疗糖尿病大鼠可通过其降血糖、抗氧化和抗炎作用减轻糖尿病视网膜病变。
