Submandibular gland and caries susceptibility in the obese Zucker rat.
BACKGROUND
Obesity is a prevalent disorder characterized as marked insulin resistance and low grade inflammation. We tested the hypothesis that obesity upregulates inflammatory markers in the submandibular gland in association with derangements of its architecture and pre-disposition to caries in obese Zucker rats (OZR). We also examined the potential impact of chromium picolinate (Cr(Pic)3), a nutritional supplement suggested to improve glycemic control, on the aforementioned parameters.


METHODS
Male OZR were treated with diets lacking and containing 5 or 10 mg/kg chromium (as Cr(Pic)3) from 6 weeks to about 6 months of age; lean Zucker rats (LZR) served as controls. Thereafter, glycemic status, salivary tissue architecture, and the levels of several inflammatory markers were determined in association with caries susceptibility.


RESULTS
OZR showed reduced insulin sensitivity, increased ratio of phospho-nuclear factor-kappa B (NF-κB) to total NF-κB, and increased intercellular adhesion molecule-1 level but similar histological features compared to LZR. Importantly, compared to LZR, OZR displayed rampant caries and a tendency for reduced dentin mineral density. Treatment of OZR with Cr(Pic)3 attenuated upregulation of these proinflammatory indicators in association with reduced severity of caries without improving insulin sensitivity.


CONCLUSIONS
Obesity promotes proinflammatory changes within the submandibular gland, without affecting glandular architecture, in association with rampant caries; Cr(Pic)3 treatment provided some protective effects.
Department of Oral Biology, Medical College of Georgia School of Dentistry, Augusta, Georgia 30912-1128, USA. Mmozaffa@mail.mcg.edu
Mahmood S
MS
Mozaffari
Rafik
R
Abdelsayed
Ibrahim
I
Zakhary
Mohammed
M
El-Salanty
Jun Yao
JY
Liu
Hereward
H
Wimborne
Ahmed
A
El-Marakby
D000818:Animals; D003731:Dental Caries / Q000209:etiology*; D003733:Dental Caries Susceptibility / Q000187:drug effects; D019587:Dietary Supplements; D018836:Inflammation Mediators / Q000378:metabolism; D007333:Insulin Resistance / Q000502:physiology; D008297:Male; D016328:NF-kappa B / Q000378:metabolism; D009765:Obesity / Q000150:complications / Q000503:physiopathology*; D010848:Picolinic Acids / Q000494:pharmacology; D051381:Rats; D011924:Rats, Zucker; D012793:Sialadenitis / Q000209:etiology*; D013363:Submandibular Gland / Q000378:metabolism*
D018836:Inflammation Mediators; D016328:NF-kappa B; D010848:Picolinic Acids; C030614:picolinic acid