Impact of an SPM Enriched Omega-3 Fatty Acid Dietary Supplement on Periodontal Regeneration

Abstract

Specialized pro-resolving lipid mediators (SPMs) biosynthesized from essential polyunsaturated fatty acids (PUFA) promote resolution of inflammation and enhance stem cell proliferation and differentiation leading to tissue regeneration. SPMs are derived from lipoxygenase-driven conversion of long-chain PUFA, such as arachidonic acid, eicosapentaenoic acid and docosahexaenoic acid. Periodontitis is an inflammatory disease of the supporting structures of the teeth that involves an interplay between microbial biofilm and the host immune response leading to inflammatory-immune destruction of connective tissue attachment and bone. Regeneration of hard and soft tissues lost to periodontal disease is limited and not predictable. Flap surgery, enamel matrix proteins, bone and soft tissue grafting have been employed to regenerate periodontal tissues lost to disease, generally with poor outcomes. Prior studies have shown that Resolvin E1 enhances resolution of inflammation, restores horizontal and vertical bone defects and produces significant bone regeneration. Prior work in the pig demonstrated that Benzo-Lipoxin A4 (BLXA4), a stable analog mimetic of lipoxin A4, encapsulated in nanoparticle liposomes, significantly improved surgical outcomes and improved regeneration of bone. The aim of this study was to determine whether a dietary supplement that contains the omega-3 fatty acids EPA and DHA, and is enriched with the precursors for SPMs, enhances periodontal regeneration. Interproximal periodontal defects 6 mm in depth were created using burs in 3 female adult Göttingen Miniature Pigs, the defects were created in all 4 quadrants around second and fourth premolars and were maintained by placement of sterile orthodontic wires. The sites were left untreated for 40 days to stabilize periodontal disease and ligatures were thereafter removed, and established, stable periodontal disease was surgically treated 40 days later. Each Pig was assigned to a treatment group 40 days after ligature removal; surgical debridement only (negative control), surgical debridement with delivery of 0.5 µg of BLXA4 in a lipid nanoparticle solution to each of eight treatment sites (two per quadrant) using a P20 micro-pipette (positive control), and surgical debridement and daily dietary supplementation with an enriched omega-3 supplement (Lipinova®, Solutex) (3ml, added to a small portion of regular food or Gatorade) until the end of the study. Animals were euthanized 90 days later and jaws harvested. MicroCT scans were performed before jaws samples were decalcified for histological analyses. Blood samples were obtained from each pig for metabolipidomic analysis by LC-MS/MS. Three-dimensional bone analysis with Micro CT revealed significant reduction in defect depth in the Diet and BLX4 groups compared to control (ANOVA, p 0.005). Metabololipidomics analysis revealed a significant shift in SPM profiles in the BLXA4 and diet groups compared to control. This study in a large animal model demonstrates that dietary supplementation with omega-3 PUFA enhances bone regeneration to a similar level to a very low dose of the active molecule, BLXA4. SPMs are known to activate wound healing with tissue regeneration and directly improve bone healing and regeneration. Dietary supplementation with a specific omega-3 PUFA preparation that is enriched with SPM precursors exhibited statistically significant improvement in tissue healing and regeneration.