1. ERV-1 Receptor in T2 Diabetes Associated Periodontitis
E. Breen, W. Wisitrasameewong , D. Nguyen,
G. Patil, V. Alves, S. Na, T.E. Van Dyke, M.O. Freire
IADR 2017 San Francisco
My talk will focus on the erv-1 receptor in…

2. Infectious Inflammatory Disease
Innate immunity (inflammation) serves as the first line of defense against infection.
Acute inflammation is self-perpetuating, self-limiting and is protective. If acute inflammation does not resolve and becomes chronic, tissue destruction is often a consequence. Chronic inflammation leads to activation of adaptive immunity that perpetuates the inflammatory cycle.

3. Potential Outcomes of an Inflammatory Response
This image from F and Van Dyke perio 2000 shows two potential outcomes after an inflammatory response. After an acute inflammatory reaction (visble clinically with redness, edema, heat, pain, and loss of function) there can be a predominance of pro inflammatory mediators such as prostaglandins or leukotrienes. This leads to chronic inflammation seen in diseases such as … and ends with fibriosis and scarring
However there can be a lipid mediator class switch to promote resoution of inflammation and this occurs with specialized pro resolution mediators derived from epa and dha such as l, r, p, and m..the end result is a return to homeostasis
Freire and Van Dyke; Periodontology 2000

4. Resolvin E1 (RvE1) Actions of RvE1 During Resolution of Inflammation
Specifically resolvin E1 will act on neutrophils and macrophages during resolution of inflammation and will..
Decreases neutrophil migration
Diminishes secretion of pro-inflammatory cytokines
Increases neutrophil apoptosis
Increases clearance of microorganisms and apoptotic neutrophils by macrophage phagocytosis and efferocytosis

5. RvE1 Ligand and ERV-1 Receptor
RvE1 is an EPA derived resolvin
ERV1 (aka chemR23) is the cognate GPCR for RvE1
The regulation of expression and function of ERV1 in health and disease is not known.
As previously mentioned RvE1 is an..

6. Type 2 Diabetes and Periodontitis
Periodontitis is an infectious inflammatory disease characterized by excess inflammatory tissue damage associated with periodontal microbiome dysbiosis.
T2D is an inflammatory metabolic disorder characterized by progressive insulin resistance and loss of β-cell function in the pancreas.
The pathogenesis of periodontitis and T2D impact each other bi-directionally.
Two very prevalent diseases seen with unresolved chronic inflammation include t2d and periodontitis
Dysbiosis..shift from good bacteria to bad bacteria
Patients with diabetes show more severe periodontal disease and patients with periodontal disease show higher glycemic levels

7. Objective
The objective of this study is to characterize the function and expression of murine ERV1 in T2D-associated periodontitis.

8. Materials and Methods
Ligature induced periodontitis (Hajishengallis 2013) progression was compared in obese T2D, normal healthy and ERV1 transgenic mice
Three strains of mice (4-5 weeks old)
Wild Type
db/db
ERV1 transgenic
Four time points
days 0, 3, 7, and 14
Used 5-0 silk sutures, mice were anesthetized with kemaine/zylazine solution
Wrapped around maxillary second molar
Spontaenous mutation in leptin receptor

9. Materials and Methods
Histological analysis was done in order to quantify:
Bone loss (hematoxylin and eosin)
Osteoclastic activity- TRAP positive cells (tartrate resistant acid phosphatase)
ERV1 Expression (Immunohistochemistry)
Micro-CT was performed on the jaws for 3D volumetric visualization of bone
At each specific time point mice were sacrificed, jaws were harvested, jaws were fixed , micro ct was run for volumetric evaluation, jaws were decalcified for histological processing after which they were stained for h and e do evaluate bone loss, trap to evaluate osteoclastic activity, and IHC for erv1 expression
H and e staining-hematoxylin and eosin staining
Trap staining; tartrate resistant acid phosphatase staining

10. Bone Tissue Here we have the bone tissue over two week period
Dd/db mice show less bone even at day 0 and the most bone loss over 14 days
Wt show a continous decline
Erv1 mice show very little bone loss and some protection until day 7 after which they show a sharp increase in bone reroption till day 14

11. Micro-CT Visualization
No Ligature
Day 3
Day 7
Day 14 WT
db/db
These are the micro ct images which coorelate with the gragh just presented
Diabetic have bone loss at day 0 and continues
Wild type shows contious bone loss through day 14
And erv1 has very little bone loss until after day 7
ERV1

12. Osteoclast Activity
At each time point db mice had the greatest osteoclastic activity
Up to day 7 there was an increase in osteoclastic activity in the wild type and erv1
Day 7 was peak osteoclastic activity for all mice
After day 7 all mice showed a decrease in osteoclastic activity; with the erv1 mouse having a slightly higher osteoclastic activity then wild type

13. ERV1 Expression db/db Wild Type ERV1
Here we have immunohistochemistry stained samples from baseline in the gingival tissues surrounding the teeth
We can see an increase in the erv1 receptor expression in db/db mice
Wild type shows no expression and erv1 does show some expression compared to wild type

14. Conclusions
T2 diabetic mice (db/db) exhibit mores severe periodontal alveolar bone loss.
ERV1 transgenic mice show some protection from ligature induced alveolar bone loss.
Osteoclastic activity is markedly increased in db/db mouse alveolar bone .
ERV1 receptor expression is markedly increased in db/db mouse gingiva at baseline. WT (health) shows no expression and the ERV1 transgenic shows increased expression over WT.
The data support earlier findings suggesting that ERV1 is highly upregulated in periodontal tissues in T2D. Over-expression in the ERV1 transgenic affords protection from periodontitis , but the persistence of inflammation in T2D with increased periodontitis suggests that the receptor is non-functional.
So in conclusion