Vitamin D and parotid gland function in the rat.

Abstract

SUMMARY1. We previously reported that parotid gland secretion is decreased in rats deprived of vitamin D (Glijer, Peterfy & Tenenhouse, 1985). In the present study we examine whether this effect is a direct result of the absence of vitamin D or due to the secondary systemic effects of vitamin D deficiency.2. Offspring of rats maintained on a calcium-supplemented (1-2%), vitamin-Ddeficient diet were weaned onto the same diet and examined after 8 weeks. Using this method it was possible to maintain serum calcium and parathyroid hormone concentrations within normal limits. Serum 25-hydroxyvitamin D (25(OH)D3) was not detectable, but 1,25-dihydroxyvitamin D (1,25(OH)2D3) concentrations were normal.3. Pilocarpine-stimulated flow of parotid saliva was reduced 57 % in vitamin-Ddeprived animals, but amylase secretion was unchanged. Treatment with vitamin D3 returned flow rates to normal.4. The concentration of calcium in parotid saliva was normal in vitamin-Ddeprived rats, although total parotid calcium output was reduced 57 %.5. Pilocarpine-stimulated salivary flow from submandibular gland, a tissue which does not possess 1,25(OH)2D3 receptors, was normal in vitamin-D-deprived rats.6. Heart rate and arterial blood pressure changes in response to i.v. pilocarpine administration were identical in normal and vitamin-D-deficient rats.7. Auriculotemporal nerve-stimulated flow of parotid saliva was also reduced by 50% and administration of vitamin D3 to these rats corrected this abnormality.8. It is concluded that fluid and electrolyte secretion from parotid gland is directly dependent on vitamin D; abnormal parotid gland function seen in vitamin-Ddeficient rats is not due to secondary hypocalcaemia or hyperparathyroidism, nor can it be explained by haemodynamic changes evoked during systemic administration of pilocarpine. We further conclude that the metabolite of vitamin D responsible for this effect is not 1,25(OH)2D3.

The effect of 14 weeks of vitamin D3 supplementation on antimicrobial peptides and proteins in athletes

“…Several animal studies have demonstrated that vitamin D receptors are present in the parotid, submandibular and sublingual salivary glands, which suggest a possible role for vitamin D in the regulation of salivary secretion. This is supported by the finding that salivary flow rates were stimulated after treatment with vitamin D 3 in vitamin D-deficient rats (Peterfy, Tenenhouse, & Yu, 1988;Stumpf, 2008). Although the influence of vitamin D on salivary flow rate has not yet been demonstrated in humans, the finding that there was a significant positive correlation between plasma total 25(OH)D concentration and salivary flow rate in the endurance athlete cohort (N = 225) (unpublished data in our previous study (He et al, 2013), r = 0.196, P = 0.003; Pearson correlation test) might lend some support to this suggestion.…”

Low Serum 25-Hydroxyvitamin D Levels Are Associated with Dry Eye Syndrome

“…In mice, vitamin D has been shown to suppress ocular surface inflammation by inhibiting Langerhans cell migration into corneas [ 54 ], thus inhibiting corneal neovascularization [ 55 ]. Furthermore, salivary glands and their epithelial and myoepithelial cells are major vitamin D targets [ 19 ], and fluid and electrolyte secretion from the parotid gland is dependent on vitamin D directly [ 20 ]. Thus, lacrimal glands as well as corneal epithelial cells also may be affected by vitamin D. It has been reported that vitamin D deficiency is prevalent in patients with Sjogren's syndrome and that female patients with Sjogren's syndrome are at risk for vitamin D deficiency [ 56 ].…”

“…Vitamin D is produced during exposure to sunlight, and is known to regulate calcium and phosphate homeostasis [ 10 ]. However, vitamin D receptor has been discovered in most tissues and cells in human body, including corneal epithelial cells [ 18 ], salivary glands [ 19 , 20 ], mammary glands [ 10 ], sebaceous glands [ 21 ], and immune cells [ 10 ]. Vitamin D has been suggested to play an essential role in these organs.…”

Effects of vitamin D supplementation on salivary immune responses during Marine Corps basic training

“…SIgA and cathelicidin serve as “the first line of defense” against pathogens at the mucosal surface . SIgA is an indicator of mucosal immunity, and vitamin D is involved in regulating salivary secretions . Cathelicidin is also produced at mucosal surfaces, possessing a broad range of antimicrobial activity, and its production is dependent upon sufficient vitamin D levels .…”