Blackcurrant press cake by-product: Increased chemical bioaccessibility and reduced antioxidant protection after in vitro simulation of gastrointestinal digestion.

This study describes the bioaccessibility in terms of total phenolic content (TPC) and antioxidant capacity before and after in vitro digestion from blackcurrant press cake extracts (BPC) and the bioactivity in cell culture, human erythrocytes as well as the in silico analysis. Chemical analysis of BPC presented an increase in TPC (270%) and anthocyanins (136%) after in vitro digestion, resulting in an improvement of antioxidant activity (DPPH 112%; FRAP: 153%). This behavior may be related to the highest activity of cyanidin-3-rutinoside, as confirmed by in silico analysis. The digested BPC did not exert cytotoxicity in cells and showed less antioxidant activity against the oxidative damage induced in endothelial cells and human erythrocytes compared to the non-digested extract. The results raise a question about the reliability we should place on results obtained only from crude samples, especially those that will be used to produce foods or nutraceuticals.

A new look at the role of nitric oxide in preeclampsia: Protein S-nitrosylation.

The formation of S-nitrosothiols (SNOs) occurs with the reaction of nitric oxide (NO) and free thiol groups in proteins. This process, called S-nitrosylation, allows NO to interfere with or even modulate a variety of cellular functions, culminating with the modification of protein trafficking, redox state, and cell cycle. Furthermore, NO plays a role in modulating a wide range of functions in endothelial cells specifically, including inflammation, apoptosis, permeability, migration, and cell growth. As such, NO acts as a mediator in several physiological processes. The interaction between endothelial nitric oxide synthase (eNOS) and proteins that are to be targeted for S-nitrosylation is a key determinant of the specificity of NO signaling. Deficits in the bioavailability of NO have been associated with pregnancy-related disorders, such as preeclampsia (PE). The study of S-nitrosylation in PE, as well as the identification of targeted proteins, may contribute to a better understanding of its pathophysiology and the development of drugs for the treatment of PE patients. In this review, we aimed to present the mechanism of S-nitrosylation, the regulatory pathways, and some proteins by which S-nitrosylation can modulate NO availability with a potential impact on PE.