Functionalization of selenium nanoparticles with olive polyphenols - impact on toxicity and antioxidative activity.

Selenium nanoparticles (SeNPs) represent novel selenium (Se) formulation characterized by improved biocompatibility and a wider therapeutic range in comparison to inorganic Se. The aim of this work was to investigate the possibilities of functionalization of SeNPs with olive pomace extract (OPE), rich in health-promoting polyphenols, and to obtain innovative forms of nutraceuticals. Cytotoxic and antioxidative activities of four types of SeNPs (polyvinylpyrrolidone stabilized (PVP SeNPs), polysorbate stabilized (PS SeNPs), polyvinylpyrrolidone stabilized and functionalized using OPE (f PVP SeNPs) and polysorbate stabilized and functionalized using OPE (f PS SeNPs) were investigated. SeNPs showed lower toxicity on human hepatocellular carcinoma (HepG2) and human colorectal adenocarcinoma (Caco2) cells compared to selenite. Functionalization with polyphenols significantly improved their direct antiradical (f PVP SeNPs: 24.4 ± 1.84 and f PS SeNPs: 30.9 ± 2.47 mg TE/mmol Se) and reducing properties (f PVP SeNPs: 50 ± 3.16 and f PS SeNPs: 53.6 ± 3.22 mg GAE/mmol) compared to non-functionalized SeNPs. The significant impact of tested SeNPs on intracellular antioxidative mechanisms has been observed and it was dependent on both cell type and physico-chemical properties of SeNPs, indicating the complexity of involved mechanisms.

Cellular Antioxidant Activity of Olive Pomace Extracts: Impact of Gastrointestinal Digestion and Cyclodextrin Encapsulation.

Olive pomace is a valuable secondary raw material rich in polyphenols, left behind after the production of olive oil. The present study investigated the protective effect of a polyphenolic extract from olive pomace (OPE) on cell viability and antioxidant defense of cultured human HepG2 cells submitted to oxidative stress induced by tert-butylhydroperoxide (tBOOH). The investigation considered possible matrix effects, impact of gastrointestinal digestion and cyclodextrin (CD) encapsulation. Pre-treatment of cells with OPE prevented cell damage and increased intracellular glutathione but did not affect the activity of glutathione peroxidase and superoxide dismutase. OPE matrix significantly enhanced cell protective effects of major antioxidants, such as hydroxytyrosol (HTS), while cyclodextrin encapsulation enhanced activity of OPE against intracellular reactive oxygen species (ROS) accumulation. The obtained results show that OPE is more potent antioxidant in comparison to equivalent dose of main polyphenols (HTS and TS) and that increasing solubility of OPE polyphenols by CD encapsulation or digestion enhances their potential to act as intracellular antioxidants. Antioxidative protection of cells by OPE was primarily achieved through direct radical-scavenging/reducing actions rather than activation of endogenous defense systems in the cell.

Alpha Lipoic Acid Reduces Symptoms and Inflammation Biomarkers in Patients with Chronic Hemorrhoidal Illness.

Background: Oral dietary supplementation is becoming increasingly popular as an addition to classical approaches for the prevention and treatment of hemorrhoidal disease. Aim: To examine the effect of orally administrated alpha lipoic acid (ALA), known for its antioxidant and anti-inflammatory properties, in the treatment of patients with permanent symptoms of hemorrhoidal disease. Methods: Patients with second- and third-degree hemorrhoids (n = 100) were enrolled into a randomized, open label, single-center trial. The study group (n = 50) was treated with 200 mg of orally administered ALA once a day during the 12-week period, the control group (n = 50) did not receive any treatment. Results: There were no significant differences in demographics, diagnosis, or exposure to major risk factors between the study and placebo group at baseline. ALA significantly improved subjective efficacy variables, such as pain and discomfort (p < 0.01) as well as objective signs of the disease, such as bleeding (p < 0.01), in comparison to the control group. Furthermore, the 3-month treatment significantly reduced the number of patients with positive C-reactive protein (CRP) value (serum CRP > 5 mg/L) from 18% before to only 2% after the treatment (χ2 = 4.65; p < 0.01). Average leukocyte count has also been significantly reduced in the treatment group (p < 0.01) from 7.29 × 109/L before to 6.18 × 109/L after treatment. Conclusions: The obtained results indicate that ALA is effective in the treatment of second- and third-degree hemorrhoids. Larger, double-blind controlled trials are needed to confirm the results and to investigate optimal treatment regimens.