Systemic effects on bone healing of a new hyaluronic acid-like bacterial exopolysaccharide.

Critical Size Defect (CSD) technique was used to evaluate the systemic activities on bone regeneration capacity of a newly discovered hyaluronic acid-like exopolysaccharide synthesized by a bacteria originating from a deep sea hydrothermal vent. Some systemic effects were previously detected on earlier experiments. A 5 mm diameter hole was made on each parietal bone of male rats. The right hole was filled with 0.5 mg of a new bacterial exopolysaccharide referenced HE 800, while the left hole remained free of any treatment. After 21 days, the holes and surrounding tissues were examined by direct examination, X-rays, and histological staining. Using HE 800, bone healing was almost complete after only 21 days in the treated hole and always complete in the control side by some systemic effect. Neovascularization was also observed along with an organized trabecular bone on both sides. No abnormal bone growth or conjunctival abnormalities were noticed. At the end of the experiment, 90.1% ( +/- 5.2) bone healing (n = 20) was observed on the treated side; conversely, the control side animals demonstrate an amazing healing 100% (+/- 0.5) by a systemic effect.