Changes in the salivary metabolome in canine hypothyroidism: A pilot study

Hypothyroidism is the most commonly diagnosed endocrine disorder in dogs. It produces a deficiency of thyroid hormones which impacts negatively the dog's quality of life. The objective of this study is to evaluate the possible changes in the salivary metabolic profile in dogs with hypothyroidism. For this purpose, targeted metabolomics analysis performed by LC/MS analysis was made in saliva samples from a group of dogs with hypothyroidism and a group of healthy dogs. Twenty-three metabolites showed a significant decrease between hypothyroid and healthy dogs, most of these associated with thyroid hormone synthesis, catecholamine synthesis, and tyrosine and phenylalanine metabolism. Based on the results, it can be stated that hypothyroidism produces changes in the metabolome of saliva and some of them can reflect the metabolic changes presented in the disease and could serve as a potential biomarker of this condition.