Redox signaling in diabetic retinopathy and opportunity for therapeutic intervention through natural products.

Diabetic retinopathy (DR) is a common serious complication of diabetes that accounts for the leading cause of blindness among the working-age population in developed countries. Despite substantial progress in therapeutic approaches, DR remains highly prevalent, indicating deeper pathomechanism studies are urgently needed. Nowadays, natural products with outstanding safety and efficacy play an increasingly vital role in drug discovery research, and some of them have the potential to facilitate the treatment of DR. In this review, we primarily revisit the contribution of redox signaling and its mediators that might be amenable to targeting DR, including Nuclear factor-kappa B (NF-κB), transforming growth factor-ß (TGF-ß), matrix metalloproteinases (MMPs), nuclear factor erythroid 2 related factor 2 (Nrf2), advanced glycation endproducts (AGEs), mammalian target of rapamycin (mTOR) as well as microRNAs. Ultimately, we summarize and evaluate the use of natural products to regulate these signaling pathways, which may increase our understanding and ability to target these important molecules and may help to achieve further clinical benefits.

Traditional Uses, Chemical Constituents and Biological Activities of Plants from the Genus Sanguisorba L.

Plants from the genus Sanguisorba have been treated as medicinal ingredients for over 2000 years. This paper reviews advances in the botanical, phytochemical and pharmacological studies of the genus. To date, more than 120 chemical constituents have been isolated and identified from these plants, especially from S. officinalis and S. minor. Among these compounds, triterpenoids, phenols and flavonoids are the primary biologically active constituents. Triterpenoids can be used as quality control markers to determine the quality of medicinal materials and their preparations. In vivo and in vitro studies have shown that plants from the genus Sanguisorba exhibit a wide range of pharmacological properties, including hemostatic, antibacterial, antitumor, neuroprotective and hypoglycemic activities. In Chinese medical practice, many drugs (e.g., tablets and powders) that contain S. officinalis roots have been used to treat leukopenia, hemorrhaging and burns. However, there is still a multitude of Sanguisorba species that have garnered little or no attention. Indeed, there are few reports concerning the clinical use and toxic effects of these plants. Further attention should be focused on the study of these species in order to gather information on their respective toxicology data, any relevant quality-control measures, and the clinical value of the crude extracts, active compounds, and bioactive metabolites from Genus Sanguisorba.