Preventive effects of a cocoa-enriched diet on gingival oxidative stress in experimental periodontitis.
BACKGROUND
Oxidative stress affects the progression of periodontitis. Cocoa is a rich source of flavonoids with antioxidant properties, which could suppress gingival oxidative stress in periodontal lesions. The purpose of the present study was to investigate the effects of a cocoa-enriched diet on gingival oxidative stress in a rat-periodontitis model.


METHODS
In this 4-week study, rats were divided into three groups (n = 8/group): a control group (fed a regular diet) and two periodontitis groups (fed a regular diet or cocoa-enriched diet [10% of food intake]). Periodontitis was induced by ligature placement around the mandibular first molars. Serum levels for reactive oxygen metabolites were measured at baseline and 2 and 4 weeks. At 4 weeks, the levels of 8-hydroxydeoxyguanosine and reduced/oxidized glutathione ratio were determined to evaluate gingival oxidative damage and antioxidant status, respectively.


RESULTS
Rats with experimental periodontitis that were fed a regular diet showed an increase in the level of serum reactive oxygen metabolites in a time-dependent manner. These rats also had an increased 8-hydroxydeoxyguanosine level and decreased reduced/oxidized glutathione ratio in the gingival tissue, inducing alveolar bone loss and polymorphonuclear leukocyte infiltration. Although experimental periodontitis was induced in the rats fed a cocoa-enriched diet, they did not show impairments in serum reactive oxygen metabolite level and gingival levels for 8-hydroxydeoxyguanosine and reduced/oxidized glutathione ratio. Alveolar bone loss and polymorphonuclear leukocyte infiltration after ligature placement were also inhibited by cocoa intake.


CONCLUSIONS
Consuming a cocoa-enriched diet could diminish periodontitis-induced oxidative stress, which, in turn, might suppress the progression of periodontitis.
Tomofuji
Takaaki
T
Department of Preventive Dentistry, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Ekuni
Daisuke
D
Irie
Koichiro
K
Azuma
Tetsuji
T
Endo
Yasumasa
Y
Tamaki
Naofumi
N
Sanbe
Toshihiro
T
Murakami
Jun
J
Yamamoto
Tatsuo
T
Morita
Manabu
M
D000080242:8-Hydroxy-2'-Deoxyguanosine; D016301:Alveolar Bone Loss / Q000473:pathology; D000818:Animals; D000975:Antioxidants / Q000032:analysis; D002099:Cacao; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000032:analysis / Q000097:blood; D004195:Disease Models, Animal; D018450:Disease Progression; D005347:Fibroblasts / Q000473:pathology; D005419:Flavonoids / Q000008:administration & dosage; D005609:Free Radicals / Q000032:analysis / Q000097:blood; D055951:Functional Food; D005881:Gingiva / Q000378:metabolism*; D005978:Glutathione / Q000032:analysis / Q000097:blood; D007958:Leukocyte Count; D008297:Male; D020556:Neutrophil Infiltration / Q000502:physiology; D009504:Neutrophils / Q000473:pathology; D010010:Osteoclasts / Q000473:pathology; D018384:Oxidative Stress / Q000502:physiology*; D017622:Periodontal Attachment Loss / Q000473:pathology; D010518:Periodontitis / Q000097:blood / Q000378:metabolism* / Q000473:pathology; D010636:Phenols / Q000008:administration & dosage; D059808:Polyphenols; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000032:analysis / Q000097:blood; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis / Q000097:blood
D000975:Antioxidants; D005419:Flavonoids; D005609:Free Radicals; D010636:Phenols; D059808:Polyphenols; D017382:Reactive Oxygen Species; D014409:Tumor Necrosis Factor-alpha; D000080242:8-Hydroxy-2'-Deoxyguanosine; D003849:Deoxyguanosine; D005978:Glutathione