Abstract
Introduction: Diabetes mellitus is known to impair salivary gland structure and function, contributing to significant oral complications and reduced quality of life. Emerging evidence suggests that vitamin D plays an important regulatory role in immune modulation, epithelial integrity, and glandular homeostasis, yet its protective potential in diabetes‑related salivary gland injury remains insufficiently understood.
Objectives: This experimental study investigates the extent to which vitamin D supplementation can mitigate diabetes‑induced biochemical and histopathological alterations in the submandibular and sublingual glands of albino rats.
Materials and Methods: This experimental study was conducted at Al‑Azhar university, Egypt in 2025, using 30 adult albino rats randomly assigned to three groups (n = 10 each): a healthy control group, a diabetic vitamin D‑deficient group, and a diabetic vitamin D‑deficient group treated with 20,000 IU vitamin D. Blood and saliva were collected weekly to assess serum and salivary electrolytes, lipid profiles (high‑density lipoprotein [HDL], low‑density lipoprotein [LDL], and very‑low‑density lipoprotein [VLDL]), salivary pH, total protein, and flow rate using standard biochemical assays. At study completion, parotid and submandibular glands were harvested for histological evaluation using hematoxylin and eosin staining. Data were collected and compared between groups.
Results: Compared to healthy control rats, diabetic vitamin D–deficient rats increased the levels of sodium, potassium, LDL, and VLDL, and salivary total protein, while decreasing the bicarbonate, HDL, salivary pH, and flow rate, with vitamin D treatment moderating, but not fully normalizing these alterations. Histopathological examination revealed extensive ductal damage, cytoplasmic vacuolization, and inflammatory changes in diabetic vitamin D–deficient glands, while vitamin D supplementation reduced the severity and frequency of these lesions.
Conclusion: Vitamin D supplementation exerted a protective effect against diabetes‑related salivary gland dysfunction, partially improving biochemical disturbances and reducing histopathological injury. Although not fully restorative, vitamin D helped mitigate the severity of diabetes‑induced alterations, underscoring its potential value as a supportive therapeutic strategy for preserving salivary gland health in diabetic conditions.