Ovotransferrin Supplementation Improves the Iron Absorption: An In Vitro Gastro-Intestinal Model

Abstract

Transferrins constitute the most important iron regulation system in vertebrates and some invertebrates. Soluble transferrins, such as bovine lactoferrin and hen egg white ovotransferrin, are glycoproteins with a very similar structure with lobes that complex with iron. In this in vitro study, a comparison of bovine lactoferrin and ovotransferrin was undertaken to confirm the comparability of biological effects. An in vitro gastric barrier model using gastric epithelial cells GTL-16 and an in vitro intestinal barrier model using CaCo-2 cells was employed to evaluate iron absorption and barrier integrity. An analysis of the molecular pathways involving DMT-1 (divalent metal transporter 1), ferritin and ferroportin was also carried out. These in vitro data demonstrate the activity of both 15% saturated and 100% saturated ovotransferrin on the iron regulation system. Compared with the commercial bovine lactoferrin, both 15% saturated and 100% saturated ovotransferrin were found to act in a more physiological manner. Based on these data, it is possible to hypothesise that ovotransferrin may be an excellent candidate for iron supplementation in humans; in particular, 15% saturated ovotransferrin is the overall best performing product. In vivo studies should be performed to confirm this in vitro data.

New Hyaluronic Acid from Plant Origin to Improve Joint Protection—An In Vitro Study

“…The human epithelial intestinal cells, CaCo-2, purchased from the American Type Culture Collection (ATCC), were cultured in Dulbecco’s Modified Eagle’s Medium/Nutrient F-12 Ham (DMEM-F12, Merck Life Science, Rome, Italy) containing 10% FBS (Merck Life Science, Rome, Italy), 2 mM L-glutamine and 1% penicillin–streptomycin (Merck Life Science, Rome, Italy) maintaining in an incubator at 37 °C and 5% CO 2 [ 66 ]. The cells used for the experiments were at passage numbers between 26 and 32 in order to preserve the integrative paracellular permeability and transport properties [ 67 ] maintaining the similarity to the intestinal absorption mechanism following oral intake in humans.…”

“…Subsequently, the best concentration of GreenIuronic ® and hyaluronic acid salt were tested on an intestinal in vitro barrier model to verify intestinal integrity through TEER measurement, tight junction analysis by ELISA kit, and permeability assay by Papp measurement, also analyzing the total amount of hyaluronic acid that had crossed the intestinal barrier. For all these experiments, cells were treated in a time-dependent manner from 2 to 6 h, as reported in the literature [ 66 ]. In addition, after each stimulation, the basolateral medium was collected to be used on chondrocytes cells.…”

“…An intestinal barrier model, using CaCo-2 cells, was performed to analyze the passage through the intestinal barrier of GreenIuronic ® and sodium hyaluronate, having, as a final destination, the chondrocyte where they could exert their beneficial effects. For this reason, the TEER values were determined with EVOM3, coupled with STX2 chopstick electrodes (World Precision Instruments, Sarasota, FL, USA); this assay was carried out every 2 days for 21 days until reaching a TEER value ≥ 400 Ωcm 2 before the stimulation [ 66 , 82 ], the time required for the cell monolayer formation, for cell differentiation, and for the exposition of the intestinal villi. On day 21, the medium at the apical and basolateral environments was changed to create different pH conditions: pH around 6.5 at the apical level (acidic pH mimicking lumen of small intestine) and pH around 7.4 at the basolateral level (neutral pH mimicking human blood) [ 69 ].…”

“…The cells were kept for 15 min at 37 °C and 5% CO 2 , after that, the TEER values were measured again before the start of the experiment to verify the stabilization of the values. The cells were stimulated with GreenIuronic ® and sodium hyaluronate for 2 h to 6 h before the successive analysis, including the permeability assay measured by Papp analysis [ 66 ]. Briefly, the Papp (cm/s) was calculated with the following formula [ 66 , 69 ]: Papp = dQ/dt ⇥ 1/m0 ⇥ 1/A ⇥ V Donor …”

Natural Products of Plants and Animal Origin Improve Albumen Quality of Chicken Eggs

“…Also, ovotransferrin peptides can form complexes easily with iron, and the bound iron can be in a free form at a pH of < 4.5 (52). Hence, ovotransferrin peptides can be used as human drugs in the form of iron supplements (53). This means they are useful in human medicine.…”