Impact of dietary macronutrient composition on alveolar bone loss in a bacterial induced periodontitis mouse model

Abstract

Background: Periodontitis is a prevalent inflammatory disease impacting connective tissue and bone metabolism. Environmental factors, including dietary macronutrients, can influence this condition. Adjusting dietary intake of macronutrients may potentially shift the immune-inflammatory balance and reduce the risk of periodontal damage.

Aims: This study sought to determine which macronutrient compositions (protein, carbohydrate, fat) are linked to either minimal ("protective") or significant ("harmful") periodontal bone loss and to investigate how these macronutrients might influence periodontitis development.

Methods: Male C57BL6/J mice, eight weeks old, were given access to one of 20 experimental diets with varying macronutrient compositions for eight weeks. At twelve weeks, periodontitis was induced using an oral wash containing Porphyromonas gingivalis and Streptococcus gordonii. One week before the study concluded, oral swabs and fecal samples were collected for microbial and metabolomic analysis. Mice were then sacrificed, and serum and caecal contents were analyzed for cytokines and short-chain fatty acids. Periodontal bone loss was assessed with MicroCT scans and ImageJ, and the data were analyzed using geometric framework for nutrition (GFN).

Results: High carbohydrate intake was linked to reduced periodontal bone loss during the developmental phase but resulted in increased serum inflammatory cytokines. Periodontal bone loss often becomes more pronounced in the later stages of periodontitis due to prolonged gingival inflammation that damages the supporting tooth structure. Carbohydrates may influence periodontitis development by affecting gut microbial composition and increasing bioactive metabolites like butyrate.

Conclusion: Among the macronutrients examined, dietary carbohydrates have the most notable effect on periodontal bone loss in mice compared to protein and fat.