Effect of high-sucrose intake on the salivary glands of growing rats: histological analysis and assessment of gene and protein expression.

Excessive sugar intake contributes to noncommunicable diseases, including dental caries. According to the Developmental Origins of Health and Disease (DOHaD) theory, early-life nutrition influences organ development and future disease susceptibility. This study examined the impact of high-sucrose intake during the growth period on salivary gland development in rats and its potential influence on dental caries after growth. Male Wistar rats were divided into two groups: a high-sucrose group (HS), receiving a 15% sucrose solution, and a control group (C), receiving distilled water. Measurements were taken from 3 to 12 weeks of age and included body weight, water and feed intake, total calorie intake, blood glucose levels, submandibular gland (SMG) weight, stimulated saliva volume, and total protein concentration. The SMGs were analyzed using histological examinations, gene expression analyses (Egf, Fgf10, Ngf, Gpx1, Ca6, Muc5b, Amy), and protein expression analyses (CA6, MUC5B). No significant differences were observed between groups in body weight, blood glucose levels, SMG weight, stimulated saliva volume, salivary total protein concentration, and histological features. However, the HS group showed altered feeding behavior with increased water and total caloric intake. Gene expression analyses revealed significant decreases in Egf and Ca6 and a notable increase in Muc5b. A decreasing trend in CA6 and a significant increase in MUC5B were observed in the SMGs. These findings indicate that a high-sucrose intake during growth can alter caries-related molecular expression in the SMG, potentially increasing dental caries susceptibility. This study supports sugar control during growth and the application of the DOHaD concept to oral diseases.