A new study shows that trans-vaccenic acid, a nutrient found in pasture-raised ruminant milk and meat, improved immune responses to cancer and viruses in mice.
Coming from the Latin word for cow (vacca), trans-vaccenic acid was also found to improve response to immunotherapy treatments, and regulate via the CREB pathway several genes related to cell proliferation, apoptosis, T cell function, and chromatin organization.
It’s a far cry from scientific research in years past that linked red meat to cancer, and suggests that ruminant meat and milk is actually a cancer preventative.
Trans-vaccenic acid, or TVA, is the predominant kind of trans-fatty acid found in human milk. The mere fact that there is a “trans” fat that is being studied for health benefits may immediately lead to complete confusion from the average American consumer trying to avoid the 3 or 4 most harmful food compounds, but when health advisory bodies, both public and private, began warning about the dangers of “trans fats” they were warning about hydrogenated vegetable oils like elaidic acid.
TVA is about 0.4 – 4% of the total fat content in dairy milk, with the upper end resulting from a longer period between milkings. Grass-fed beef is known to have a more favorable lipid profile, including more of the better unsaturated fatty acids like EPA and DHA, and more of the better saturated fats like trans-vaccenic, palmitic, stearic, and myristic acids.
Several studies suggest that grass-based diets elevate precursors for Vitamin A and E, as well as cancer-fighting antioxidants such as glutathione and superoxide dismutase.
But can it really fight off cancer?
The study was published in the journal Nature, and subjected the mice to randomized control trials which also used different techniques to isolate certain processes or compounds to get a more concrete image of the biological effects of trans-vaccenic acid, for example, TVA didn’t alter the mouse melanoma B16F10 cell proliferation or apoptosis directly, and was instead demonstrated to enhance the targeting of the melanoma tumors via T cell modulation.
To test this, the scientists fed a diet of TVA-enriched chow to mice who had breast, colon, and melanoma tumors, and then used antibodies to knock out one of the most important white blood cells in the human body: the CD8+ T cell, also known as a cytotoxic T lymphocyte, CTL, cytolytic T cell, or killer T cell. These cells are the most common weapon of the body’s adaptive immune response, and they also fight cancer.
When the mice lost their ability to produce CD8+ T cells, the trans-vaccenic acid ceased to affect the cancer cells.
Ironically, the way in which the TVA seems to work through the T cells is by activating a pathway involved in the fermentation of fiber from plant-based foods in the gut.
“Our integrated temporal genomics and protein phosphorylation analyses reveal that the cell-surface receptor GPR43 is a target of TVA,” the authors write. CPR43 is specially designed for short-chain fatty acids. TVA itself is a long-chain fatty acid—typical of meat and cheese. Short-chain fatty acids enter the systems of human nutrition when fiber is fermented in the gut by bacteria, which produce short-chain fatty acids like butyrate and beta-hydroxybutyrate as a byproduct.
Via a three-step process, involving an intracellular signaling protein called Gi, TVA leads CPR43 into enhancing CD8+ T cell function, which is a bit quirky by the way, because CPR43 is designed for short-chain fatty acids and actually downregulates CD8+ T cell production when taking them up.
It’s a good example of how many biological mechanisms have strange inbuilt workarounds, and a good example of just how complicated food items are, how far-reaching their effects can be, and what we stand to lose if we decide to exclude them from our eating patterns. WaL
PICTURED ABOVE: Pasture-raised beef was shown to contain more trans-vaccenic acid. PC: Yang, Unsplash