In Vitro Digestibility of α-Casozepine, a Benzodiazepine-like Peptide from Bovine Casein, and Biological Activity of Its Main Proteolytic Fragment

Abstract

α-Casozepine is a peptide, corresponding to the sequence 91-100 of the bovine α(s1)-casein, displaying anxiolytic activity in the rat. The α(s1)-casein tryptic hydrolysate containing this peptide decreases stress effects after oral administration in various species including man. Therefore, the stability of this peptide toward gastric and pancreatic proteases has been assessed by using pepsin, chymotrypsin/trypsin, Corolase PP, pepsin followed by chymotrypsin/trypsin or pepsin followed by Corolase PP. α-Casozepine was slowly degraded by chymotrypsin, much more sensitive to pepsin and Corolase PP but not completely destroyed after 4 h kinetics. The bonds in the region 91 to 95 of the α-casozepine were totally resistant to hydrolysis by all studied proteases. Surprisingly, a fragment, corresponding to the sequence 91-97 and found in all the hydrolysis media in significant amount, possessed an anxiolytic activity in three behavioral tests measuring this parameter. This peptide could participate in the in vivo activity of α-casozepine.

Suppression of tumour growth by orally administered osteopontin is accompanied by alterations in tumour blood vessels

“…However, di- and tri-peptides are also absorbed via the peptide transporter Pept1 (Adibi, 1997) and can be exported through the basolateral membrane (Charrier and Merlin, 2006). Furthermore, there is evidence for absorption of larger peptides on the basis of their biological activity (e.g., Vermeirssen et al , 2004; Cakir-Kiefer et al , 2011), and the development of food allergies may be related to absorption of antigenic peptides (Wickham et al , 2009). These observations suggest that intact OPN peptides may accumulate in the plasma of mice fed OPN.…”

Modestly Improved Compliance and Apparent Comfort of Horses With Aversions to Mildly Aversive Routine Health Care Procedures Following Short-Term Alpha-Casozepine Supplementation

“…For the oral route of administration, current evidence indicates that ordinary digestive enzymes in vitro produce a bioactive fragment of the peptide with demonstrated anxiolytic effects in three standard behavioral models [11].…”

Food-Derived Hemorphins Cross Intestinal and Blood–Brain Barriers In Vitro

“…This study is a first report of the passage of food-derived hemorphins, i.e., exogenous hemorphins, through the intestinal as well as the BBB in vitro (Table 1 ). Information on the in vitro absorption of alimentary proteins or of well-defined peptide sequences derived thereof has been mainly garnered from tests with milk proteins ( 34 – 36 ), much less from tests with whey proteins ( 19 , 37 ), or lately from egg albumin ( 38 ) but this information was unknown for hemorphins. The tested peptide the closest in terms of structure to hemorphins, is endomorphine-1 for which a low permeability through a caco-2 cell monolayer was reported ( 39 ).…”