Lactucaxanthin Regulates the Cascade of Retinal Oxidative Stress, Endoplasmic Reticulum Stress and Inflammatory Signaling in Diabetic Rats

Purpose The purpose of this study is to investigate the protective mechanism of lactucaxanthin against retinal angiogenesis in diabetic retinopathy. Methods Streptozotocin-induced diabetic rats were orally gavaged with either lactucaxanthin or lutein (n=12/group) for 8 weeks. Serum and retina collected from euthanized rats were subjected to assess oxidative stress, ER stress and inflammatory response. Results Lactucaxanthin administration was found to lower oxidative stress markers (protein carbonylation and lipid peroxidation) by augmenting antioxidant activity expression and ameliorated VEGF-A levels in diabetic group. Likewise, it suppressed the expression of ER stress (ATF4, ATF6, and XBP1), and inflammatory (TNF-alpha, IL-6, NF-kappa B, and ICAM-1) markers in diabetic retina. In addition, lactucaxanthin improved glucose tolerance and lipid profile under diabetic condition and suppressed the crosstalk between OS, ER stress, and inflammation. Conclusion Lactucaxanthin could be used as a promising therapeutic bioactive for treating DR condition, and retinal angiogenesis. Expert opinion Limitation of the study includes the sample size and the duration of treatment. Despite these limitations, this study has revealed the potential of lactucaxanthin in treating eye related diabetic complications. To validate the results obtained from this study, clinical study must be performed to understand the relative benefit of lactucaxanthin in DR treatment.