High-Fat Diet–Induced Morphometric Alterations in the Rat Salivary Glands

Thanit Prasitsak; Komkrith Boonmakum; Kanyanut Tiptirapong; Pokpong Ritkajorn Tungjai; Panuwat Rassaiyakarn; Kroekkiat Chinda; Aubonwan Sitthikhankaew; Siriporn Kreungnium; Thanyaporn Sang-Ngoen

doi:10.1055/s-0045-1812060

European Journal of Dentistry, Table of Contents

CC BY 4.0 · Eur J Dent
DOI: 10.1055/s-0045-1812060

Original Article

High-Fat Diet–Induced Morphometric Alterations in the Rat Salivary Glands

Authors

Thanit Prasitsak

¹Department of Oral Biology, Faculty of Dentistry, Naresuan University, Phitsanulok, Thailand
Komkrith Boonmakum

²Doctor of Dental Surgery Program Student, Faculty of Dentistry, Naresuan University, Phitsanulok, Thailand
Kanyanut Tiptirapong

²Doctor of Dental Surgery Program Student, Faculty of Dentistry, Naresuan University, Phitsanulok, Thailand
Pokpong Ritkajorn Tungjai

²Doctor of Dental Surgery Program Student, Faculty of Dentistry, Naresuan University, Phitsanulok, Thailand
Panuwat Rassaiyakarn

²Doctor of Dental Surgery Program Student, Faculty of Dentistry, Naresuan University, Phitsanulok, Thailand
Kroekkiat Chinda

³Department of Physiology, Faculty of Medical Science, Naresuan University, Phitsanulok, Thailand

⁴Integrative Cardiovascular Research Unit, Department of Physiology, Faculty of Medical Science, Naresuan University, Phitsanulok, Thailand
Aubonwan Sitthikhankaew

⁴Integrative Cardiovascular Research Unit, Department of Physiology, Faculty of Medical Science, Naresuan University, Phitsanulok, Thailand
Siriporn Kreungnium

⁴Integrative Cardiovascular Research Unit, Department of Physiology, Faculty of Medical Science, Naresuan University, Phitsanulok, Thailand
Thanyaporn Sang-Ngoen

¹Department of Oral Biology, Faculty of Dentistry, Naresuan University, Phitsanulok, Thailand

Abstract

Objectives

High-fat diet (HFD) consumption induces metabolic diseases, which lead to salivary gland alteration. However, the alteration in salivary gland remains inconclusive, and the potential protective effect of simvastatin is limited. Therefore, our study aimed to investigate the effect of HFD consumption and the protective effect of simvastatin on submandibular and sublingual glands in rats.

Materials and Methods

Eighteen male Wistar rats were divided into three groups (n = 6 per group): a control group (C) fed a standard diet, a HFD group (H), and a HFD with simvastatin group (S). After 12 weeks, blood was collected for lipid parameter analysis. Submandibular and sublingual glands were stained with hematoxylin and eosin (H&E), Masson's trichrome, periodic acid–Schiff, and alcian blue to evaluate gland architecture, fibrosis, and mucin content. Image analysis was done using imageJ software.

Statistical Analysis

Parametric data were analyzed using one-way ANOVA followed by Tukey's post hoc test. Nonparametric data were analyzed using the Kruskal–Wallis test, followed by Dunn's test. A p-value <0.05 was considered statistically significant.

Results

The low-density lipoprotein cholesterol (LDL-C) level significantly increases in the H group compared with the C group (p = 0.004). Acinar cells in both submandibular and sublingual glands were significantly smaller in the H and S groups compared with the C group (p < 0.05). Vacuole-like clear structures were more frequent in the H group. Collagen deposition in the submandibular gland was significantly higher in the H and S groups compared with controls (p = 0.005 and p = 0.011, respectively). Slightly altered mucin staining is seen in both glands.

Conclusion

HFD increased LDL-C levels and induced acinar atrophy and fibrosis in the submandibular and sublingual glands. Simvastatin did not protect against salivary gland damage from HFD consumption.

Keywords

dyslipidemia - cholesterol - salivary glands - fibrosis - image analysis - simvastatin

Full Text

References

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Supplementary Material

Supplementary Material (PDF)