Bioactive peptides animal studies

Ingredia, a French dairy company, has developed Prodiet F 200 , a milk protein hydrolysate that contains a bioactive peptide with relaxing properties. The patented product has an anti-stress effect proven by several clinical studies and does not cause the classical side effects of anxiolytics. Food supplements, chocolate and animal feed are examples of its applications (Lefranc, 2002). 

Observations of lower rates of certain chronic diseases in several Asian countries compared to the United States served as the impetus for studies that were conducted to identify the factors that were accountable (Tham et al., 1998). Consumption of soy is one factor that correlated with these lower rates. From this information, much research focused on soy protein and accompanying bioactive compounds with regard to elucidating mechanisms associated with risk markers for chronic disease, particularly CVD. The combination of macro- (protein, fiber, fat) and micro-components (isoflavones, saponins, tocopherols) as part of many traditional soy foods may underlie the epidemiological observations associated with soy intake. A body of cell culture and animal data shows potential health effects of a multitude of bioactive components in soy (i.e., saponins, phenolic acids, peptides). However, studies determining the independent effects of saponins, phenolic acids, and protease inhibitors in humans are yet to be conducted. 

The generation of bioactive peptides during microbial fermentation of milk and soybean is now well documented. Such peptides have been shown to exert several bioactivities that have been demonstrated in animal and human studies. Potential health benefits associated with bioactive peptides have been subject of growing commercial interest, especially in the context of functional foods. Milk proteins are the best-known source of bioactive peptides, but peptides with similar properties have also been identified in soybean. Anti-hypertensive peptides derived from milk proteins have already found commercial applications both in Japan and in Europe. This trend is likely to continue, although controversial results in cUnical trials and global differences in health claim regulations call for further scientific and clinical research. 

In rats with experimentally induced diabetes, circulating somatomedin levels are very low compared with values in control animals (F4, P4). As with the investigations of the effects of undernutrition, this was originally observed using bioassay methods to measure somatomedin levels and, similarly, the discovery of inhibitors of somatomedin bioactivity in the circulation of diabetic animals (see Section 3.5) raised the possibility that the apparently reduced somatomedin levels might simply be due to interference of these substances in the bioassays. More recently, RRA (B12) and RIA (Ml) studies have confirmed that the concentration of somatomedin peptides is indeed reduced in experimental diabetes. This is perhaps not surprising, since both circulating GH levels (T7), and the concentration of GH receptors on liver membranes (B13, B15), are very low in these animals. 

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