Stereology and ultrastructure of the salivary glands of diabetic Nod mice submitted to long‐term insulin treatment

Abstract

Insulin-dependent diabetes mellitus compromises the salivary glands, altering their morphology and the mechanisms of salivation, which are fundamental for oral health. Thus, the aim of the present study was to determine the effects of prolonged insulin treatment on the morphology of the salivary glands in Nod mice. Forty-five female mice were divided into five groups: nine positive diabetic Nod mice for 10 days (group 1), nine positive diabetic Nod mice for 20 days (group 2), nine diabetic Nod mice for 10 days (group 3), nine diabetic Nod mice for 20 days (group 4), and nine nondiabetic BALB/c mice (group 5). Animals of groups 3 and 4 received 4 -5 U of insulin daily, whereas animals of groups 1, 2, and 5 received the same dose of physiological saline simulating the experimental conditions. Samples of the salivary glands were analyzed by light, transmission, and scanning electron microscopies. The results showed intense alterations in diabetic animals characterized by nuclear and cytoplasmic atrophy, biomembrane disorganization, an increase in fibrillar components of the extracellular matrix, and the presence of inflammatory cells. Insulin treatment exerted positive effects on the recovery of the changes resulting from the diabetic state in both parotid and submandibular glands but the pattern continued to be altered. It can be concluded that, in addition to compromising the processes of tissue maintenance and renewal, tissue destructuring leads to alterations in functional mechanisms in both diabetic animals and animals submitted to glycemic control.

Diabetes causes morphological changes in human submandibular gland: a morphometric study

“…Most investigations were focused on salivary glands with sialadenosis, namely with a severe grade of atrophy and cell degeneration. On the other hand, experiments on rats with induced diabetes and Nod mice showed that submandibular gland features are still affected or only partly restored when glycemic level was controlled by insulin treatment . Our results show that diabetes causes significant changes in human submandibular gland even when glycemia is well controlled and clinical signs of gland malfunctions are absent.…”

Effect of experimentally induced diabetes on adult albino ratsʼ ventral prostate gland and role of selenium

“…Several studies observed high serum glucose levels in diabetic rodents [30]. Sodium selenite had been found to significantly decrease the high blood glucose level observed in diabetes [31].…”

Chronic hyperglycaemia increases TGFβ2 signaling and the expression of extracellular matrix proteins in the rat parotid gland

“…It is possible that these reported alterations began with increased synthesis of laminin and other matrix proteins. Caldeira et al (2005), studying non- Parotid glands of control (C), 30 days diabetic (D30) and 60 days diabetic (D60) rats were submitted to immunofluorescence for different ECM proteins. Initial labeling for each protein was considered (+), and alterations observed in diabetes (++ for medium and +++ for high) were compared to the initial control.…”