The objective of this research was to examine the value of a novel cell-based antioxidant protection in erythrocytes (CAP-e)* assay for the evaluation of whether antioxidants in natural products are capable of penetrating and protecting live cells from oxidative damage.
The assay uses basic chemical principles, similar to those used with the ORAC test, to measure specific effects of products on a highly simplistic cell type, the erythrocyte (red blood cell). The advantage of utilizing the erythrocyte for the assay is that this cell type does not perform cellular signaling, undergo apoptosis, or produce reactive oxygen species, whereas all other cell types used in cell-based assays can.
We have tested natural products with known ORAC values, and found that certain products such as the freeze-dried Acai berry, with an extremely high ORAC of 1,027 μmol Trolox equivalents per gram, also provided good protection of cells from oxidative damage. We have also identified a bovine colostrum whey-based extract, Immunel, with a known ORAC value of 18 μmol Trolox equivalents per gram, which was able to protect cells better than would be expected based on the product’s ORAC value alone.
Furthermore, we used a version of the CAP-e method to test serum samples from a clinical pilot study, testing antioxidant uptake after consumption of placebo versus MonaVie Active, a juice rich in Acai. The CAP-e assay was able to detect an increase in serum antioxidants, and the data correlated with changes in lipid peroxidation as measured by the T BARS test.
We are currently performing a single laboratory validation for the assay, using a select panel of natural products of plant, animal, and microbial origins.