The researchers, who are associated with schools of dental medicine in the United States, Switzerland and Canada, looked at the effects of resolvin E1. Their study, titled Resolvin E1 Promotes Bone Preservation Under Inflammatory Conditions, was published in June in the journal Frontiers in Immunology.
Preserving bone tissue is a key facet of dental health, especially in aging individuals and others who are prone to periodontal disease. Invasion of jaw bone tissue by pathogenic bacteria that proliferate in dental plaques is a prime reason for bone loss in the jaw and the subsequent shrinking of good treatment options for preserving a patient’s existing teeth or successfully replacing them with dental implants.
Resolving E1 modulates immune system ratio
Past research has laid out a role for Omega-3s in quelling inflammatory states. And studies have also posited a role for omega-3s in bone health, a body of research that potentially could be bolstered by the periodontal study. The dental researchers used the bones of mice to measure the effects of resolving E1 in protecting bone tissue in animals given an induced inflammatory challenge.
“Animal and human trials have demonstrated that regular diets rich in ω-3 PUFA result in a reduction in bone turnover and an increase bone mineral density. However, the exact mechanism of action of ω-3 PUFA on a molecular level is still not completely clear,” the researchers wrote.
“Together, our results provide evidence for RvE1’s direct impact on the skeletal system; regulating pathologic inflammation-induced bone resorption by control of the RANKL/OPG ratio [one way pathogenic inflammatory states can be measured] and downstream genetic events,” they concluded.
Metabolites form basis of innovation
Resolvins, protectins—all of the metabolites of EPA and DHA—have become the thin wedge of innovation within the omega-3s research sphere and has been a hot topic in raw material and product innovation, too. For example, late last year Marine Ingredients, a division of KD Pharma, launched an ingredient called NutraSolv3, an oil taken from the livers of Alaska cod that is said to be rich in both EPA and DHA as well as metabolites of those fatty acids. According to the company, those include 14-HDHA (hydroxydocosahexaenoic acid), 17-HDHA and 18-HEPE (hydroxyeicosapentaenoic acid). A finished product based on these so-called ‘Pre-resovling Mediators’ is on the market in the form of Metagenics’ SPM Active, which is a fractionated marine lipid ingredient standardized to 17-HDHA and 18-HEPE content.
Gerard Bannenberg, PhD, director of compliance and scientific outreach for the Global Organization of EPA and DHA Omega-3s (GOED), said studies like these are helpful in more fully elucidating what omega-3s are actually doing in the body.
“Apart from the roles of EPA, DPA and DHA in cell membranes, these omega-3 long-chain polyunsaturated fatty acids are the substrate for the enzymatic formation of several families of signaling substances called Specialized Pro-resolving Mediators (SPMs), which include the resolvins,” he said.
“The capacity of the body to make SPMs is necessary to maintaining a balance between appropriate host-defense and turning off inflammatory responses so that they do not cause irreversible damage to our tissues. SPMs play regulatory roles in all organs and tissues, including bone tissue. Bone loss as a result of experimental periodontitis in rabbits can be significantly prevented, and even restored, by resolvin E1. This animal model has been important in demonstrating the ability to induce the regeneration of damaged bone tissue,” Bannenberg added.
Reductionism seen as issue
But one of the world’s most prominent omega-3s researchers, Prof. William Harris, PhD, of the Sanford School of Medicine at the University of South Dakota, was not as sanguine about the ultimate applicability of the bone tissue cell study for nutritional products based on omega-3s. The study’s reductionist approach makes relating the results back to the whole nutrient problematic, he said.
“I don’t know if this is physiologically relevant,” Harris said. “This is a piece of the puzzle, but this is far from being able to say that omega-3s should have a bigger role in bone health.”
“When you feed EPA and DHA to humans, there are lots of things that are produced, like prostaglandins and leukotrienes, for example. Who’s to say that this resolvin would be doing the same thing in the body in the concentrations that exist in humans?” Harris added.
Source: Frontiers in Immunology
“Resolvin E1 Promotes Bone Preservation Under Inflammatory Conditions”
Published online 2018 Jun 12. doi: 10.3389/fimmu.2018.01300
Authors: El Kholy K, Freire M, Chen T, Van Dyke TE