Cure of dry mouth by Jersey cow milk

The administration of Leu57-Leu58-His59-Lys60 (LLHK), Leu58-His59-Lys60 (LHK), and His59-Lys60 (HK) from β-lactoglobulin C variant, which is specific to Jersey cow milk, has been shown to prevent and/or restore the age-dependent atrophy and functional decline of salivary glands by affecting gene expression in elderly rats. In this study, we investigated the effect of Jersey cow defatted milk on salivary volume and composition in elderly persons. Participants (aged 85 to 98, n = 8) were administered defatted dry milk from Jersey cows twice a day for 4 weeks. Before and after 4 weeks from the start of drinking, saliva was collected and weighed. Salivary cystatin S and amylase levels were analyzed by Western blotting. To assess the effect of Jersey cow defatted milk on taste perception, questionnaires were used. Salivary volume after oral administration of 40 g of Jersey cow defatted dry milk daily for 4 weeks was 1.8 times higher than that before administration. Salivary cystatin S and amylase levels significantly increased after administration of Jersey cow defatted dry milk. Moreover, all participants who had taste impairment reported improved taste perception after administration. The administration of Jersey cow defatted dry milk increased salivary volume and changed the composition of saliva in elderly persons. Furthermore, it improved taste perception

等張または低張条件下のラット耳下腺腺房細胞におけるα１-アドレナリン受容体誘導性のAQP5細胞内移動機序

Defective cellular trafficking of aquaporin-5 (AQP5) to the apical plasma membrane (APM) in salivary glands is associated with the loss of salivary fluid secretion. To examine mechanisms of α1-adrenoceptor (AR)-induced trafficking of AQP5, immunoconfocal microscopy and Western blot analysis were used to analyze AQP5 localization in parotid tissues stimulated with phenylephrine under different osmolality. Phenylephrine-induced trafficking of AQP5 to the APM and lateral plasma membrane (LPM) was mediated via the α1A-AR subtype, but not the α1B- and α1D-AR subtypes. Phenylephrine-induced trafficking of AQP5 was inhibited by ODQ and KT5823, inhibitors of nitric oxide (NO)-stimulated guanylcyclase (GC) and protein kinase (PK) G, respectively, indicating the involvement of the NO/ soluble (c) GC/PKG signaling pathway. Under isotonic conditions, phenylephrine-induced trafficking was inhibited by La3+, implying the participation of store-operated Ca2+ channel. Under hypotonic conditions, phenylephrine-induced trafficking of AQP5 to the APM was higher than that under isotonic conditions. Under non-stimulated conditions, hypotonicity-induced trafficking of AQP5 to the APM was inhibited by ruthenium red and La3+, suggesting the involvement of extracellular Ca2+ entry. Thus, α1A-AR activation induced the trafficking of AQP5 to the APM and LPM via the Ca2+/ cyclic guanosine monophosphate (cGMP)/PKG signaling pathway, which is associated with store-operated Ca2+ entry

Long-Term Oral Administration of LLHK, LHK, and HK Alters Gene Expression Profile and Restores Age-Dependent Atrophy and Dysfunction of Rat Salivary Glands

Xerostomia, also known as dry mouth, is caused by a reduction in salivary secretion and by changes in the composition of saliva associated with the malfunction of salivary glands. Xerostomia decreases quality of life. In the present study, we investigated the effects of peptides derived from β-lactoglobulin C on age-dependent atrophy, gene expression profiles, and the dysfunction of salivary glands. Long-term oral administration of Leu57-Leu58-His59-Lys60 (LLHK), Leu58-His59-Lys60 (LHK) and His59-Lys60 (HK) peptides induced salivary secretion and prevented and/or reversed the age-dependent atrophy of salivary glands in older rats. The transcripts of 78 genes were upregulated and those of 81 genes were downregulated by more than 2.0-fold (p ≤ 0.05) after LHK treatment. LHK upregulated major salivary protein genes such as proline-rich proteins (Prpmp5, Prb3, Prp2, Prb1, Prp15), cystatins (Cst5, Cyss, Vegp2), amylases (Amy1a, Amy2a3), and lysozyme (Lyzl1), suggesting that LLHK, LHK, and HK restored normal salivary function. The AP-2 transcription factor gene (Tcfap2b) was also induced significantly by LHK treatment. These results suggest that LLHK, LHK, and HK-administration may prevent and/or reverse the age-dependent atrophy and functional decline of salivary glands by affecting gene expression

Mechanisms Underlying Activation of α1-Adrenergic Receptor-Induced Trafficking of AQP5 in Rat Parotid Acinar Cells under Isotonic or Hypotonic Conditions

Defective cellular trafficking of aquaporin-5 (AQP5) to the apical plasma membrane (APM) in salivary glands is associated with the loss of salivary fluid secretion. To examine mechanisms of α1-adrenoceptor (AR)-induced trafficking of AQP5, immunoconfocal microscopy and Western blot analysis were used to analyze AQP5 localization in parotid tissues stimulated with phenylephrine under different osmolality. Phenylephrine-induced trafficking of AQP5 to the APM and lateral plasma membrane (LPM) was mediated via the α1A-AR subtype, but not the α1B- and α1D-AR subtypes. Phenylephrine-induced trafficking of AQP5 was inhibited by ODQ and KT5823, inhibitors of nitric oxide (NO)-stimulated guanylcyclase (GC) and protein kinase (PK) G, respectively, indicating the involvement of the NO/ soluble (c) GC/PKG signaling pathway. Under isotonic conditions, phenylephrine-induced trafficking was inhibited by La3+, implying the participation of store-operated Ca2+ channel. Under hypotonic conditions, phenylephrine-induced trafficking of AQP5 to the APM was higher than that under isotonic conditions. Under non-stimulated conditions, hypotonicity-induced trafficking of AQP5 to the APM was inhibited by ruthenium red and La3+, suggesting the involvement of extracellular Ca2+ entry. Thus, α1A-AR activation induced the trafficking of AQP5 to the APM and LPM via the Ca2+/ cyclic guanosine monophosphate (cGMP)/PKG signaling pathway, which is associated with store-operated Ca2+ entry