There is increased interest in following a healthy lifestyle and consuming a substantial portion of secondary plant metabolites, such as polyphenols, due to their benefits for the human body. Food products enriched with various forms of fruits and vegetables are sources of pro-health components. Nevertheless, in many cases, the level of their activities is changed in in vivo conditions. The changes are strictly connected with processes in the digestive system that transfigure the structure of the active compounds and simultaneously keep or modify their biological activities. Much attention has focused on their bioavailability, a prerequisite for further physiological functions. As human studies are time consuming, costly and restricted by ethical concerns, in vitro models for investigating the effects of digestion on these compounds have been developed to predict their release from the food matrix, as well as their bioaccessibility. Most typically, models simulate digestion in the oral cavity, the stomach, the small intestine and, occasionally, the large intestine. The presented review aims to discuss the impact of in vitro digestion on the composition, bioaccessibility and antioxidant activity of food polyphenols. Additionally, we consider the influence of pH on antioxidant changes in the aforementioned substances.

Therapeutic approaches for the induction of immune tolerance remain an unmet clinical need for the treatment of autoimmune diseases, including multiple sclerosis (MS). Based on its role in the control of the immune response, the ligand-activated transcription factor aryl hydrocarbon receptor (AhR) is a candidate target for novel immunotherapies. Here, we report the development of AhR-activating nanoliposomes (NLPs) to induce antigen-specific tolerance. NLPs loaded with the AhR agonist ITE and a T cell epitope from myelin oligodendrocyte glycoprotein (MOG)35–55 induced tolerogenic dendritic cells and suppressed the development of experimental autoimmune encephalomyelitis (EAE), a preclinical model of MS, in preventive and therapeutic setups. EAE suppression was associated with the expansion of MOG35–55-specific FoxP3+ regulatory T cells (Treg cells) and type 1 regulatory T cells (Tr1 cells), concomitant with a reduction in central nervous system-infiltrating effector T cells (Teff cells). Notably, NLPs induced bystander suppression in the EAE model established in C57BL/6 × SJL F1 mice. Moreover, NLPs ameliorated chronic progressive EAE in nonobese diabetic mice, a model which resembles some aspects of secondary progressive MS. In summary, these studies describe a platform for the therapeutic induction of antigen-specific tolerance in autoimmune diseases.

Background To examine morphological and functional results after pars plana vitrectomy (PPV) with sulfur hexafluoride (SF6) gas tamponade due to macula-on and macula-off rhegmatogenous retinal detachment (RRD) during 6 months of the follow-up. Methods The study included 62 eyes that underwent successful PPV with SF6 tamponade with macula-on (34 eyes) and macula-off (28 eyes) RRD preoperatively. The best-corrected visual acuity (BCVA), Amsler test, M-charts, optical coherence tomography (OCT) and microperimetry were performed at 1, 3 and 6 months postoperatively. Results Results of the Amsler test were abnormal postoperatively in 54% of the patients in the group with macula-off and in 32% of the patients with macula-on RRD. Horizontal M-charts improved significantly from 0.33 to 0.2, vertical M-charts– from 0.29 to 0.17 during 6 months of the follow-up. There was a significant increase in the central retinal thickness (CRT) and average thickness (AT) between follow-up examinations only in the macula-off group. 29 of 62 eyes (47%) after surgery (equally with macula-on and macula-off RRD) showed morphological changes in OCT in the macular region, as epiretinal membrane, macular edema, subretinal fluid or alterations of the outer layers of the retina. The average threshold in microperimetry increased significantly within both groups during the follow-up. Conclusion Both horizontal and vertical M-charts scores, as were as microperimetry sensitivity improved significantly during the 6 months of the follow-up both in macula-on and macula-off group. Although PPV with SF6 gas tamponade was successful, almost half of eyes revealed anatomical changes in the macular region in OCT both with macula-on and macula-off group. Trial Registration Current Controlled Trials NCT03902795 registered on 03/04/2019. Retrospectively registered.

Aim To report outcomes of pars plana vitrectomy (PPV) in pediatric retinal detachment (RD) with proliferative vitreoretinopathy (PVR), complications, factors influencing the final anatomical and functional results. Methods Retrospective consecutive case series of 14 eyes. Average postoperative follow-up period was 34 months. Results Mean age of patients was 10 years; eleven patients (79%) were males. The most common etiology was trauma (57%), the second—myopia (36%) and one case of uveitis (7%). At the day of presentation, the best-corrected visual acuity (BCVA) was worse than hand motion (50%); macula was detached in 86% of cases. Simultaneous PPV and phacoemulsification with intraocular lens (IOL) implantation were performed in 12 cases (86%). The most common endotamponade during PPV was silicone oil (93%). Anatomic reattachment was accomplished in 86% of cases. Final BCVA was equal or better than 0.1 in 50% of patients. The postoperative complications were found in 5 eyes (36%). Conclusion Complete PPV was allowed for anatomically reattached retina and preserved vision in pediatric complex RD with PVR. However, visual outcomes were not satisfactory. Preserving vision in children with RD is of great importance for their future motor and intellectual development. This trial is registered with ClinicalTrials.gov Identifier: NCT03208205.

Kynurenines, products of tryptophan (TRP) metabolism, display neurotoxic (e.g., 3-hydroxykynurenine; 3-HK), or neuroprotective (e.g., kynurenic acid; KYNA) properties. Imbalance between the enzymes constituting the kynurenine pathway (KP) plays a role in several disease, including neurodegeneration. In this study, we track changes in concentrations of tryptophan and its selected metabolites after damage to retinal ganglion cells and link this data with expression of KP enzymes. Brown-Norway rats were subjected to intravitreal N-methyl-D-aspartate (NMDA) injection or partial optic nerve crush (PONC). Retinas were collected 2 and 7 days after the completion of PONC or NMDA injection. Concentrations of TRP, kynurenine (KYN), and KYNA were determined by high performance liquid chromatography (HPLC). Data on gene expression in the rat retina were extracted from GEO, public microarray experiments database. Two days after NMDA injection concentration of TRP decreased, while KYN and KYNA increased. At day 7 compared to day 2 decrease of KYN, KYNA and further reduction of TRP concentration were observed, but on day 7 KYN concentration was still elevated when compared to controls. At day 2 and 7 after NMDA injection no statistically significant alterations of 3-HK were observed. TRP and 3-HK concentration was higher in PONC group than in controls. However, both KYN and KYNA were lower. At day seven concentration of TRP, 3-HK, and KYN was higher, whereas concentration of KYNA declined. In vivo experiments showed that retinal damage or optic nerve lesion affect TRP metabolism via KP. However, the pattern of changes in metabolite concentrations was different depending on the model. In particular, in PONC KYNA and KYN levels were decreased and 3-HK elevated. These observations correspond with data on expression of genes encoding KP enzymes assessed after optic nerve crush or transection. After intraorbital optic nerve crush downregulation of KyatI and KyatIII between 24 h and 3 days after procedure was observed. Kmo expression was transiently upregulated (12 h after the procedures). After intraorbital optic nerve transsection (IONT) Kmo expression was upregulated after 48 h and 7 days, KyatI and KyatIII were downregulated after 12, 48 h, 7 days and upregulated after 15 days. Collected data point to the conclusion that development of therapeutic strategies targeting the KP could be beneficial in diseases involving retinal neurodegeneration.