Salivary glands and adipobiology

Abstract

This review explores the functional relationships between salivary glands and adipose tissue. Since salivary glands, and in particular the submandibular glands, exert profound systemic effects on organs and inflammatory responses outside the gastrointestinal tract, the question arises if these glands also impact the body's physiological response to increases in adipose tissue deposition and secretion. And, if the adipose tissue deposition and secretion impact the salivary gland's physiological response. To date the evidence is relatively weak that salivary glands significantly impact obesity, or that their function is dramatically altered by obesity, and that the measurement of metabolic peptides in saliva will lead to diagnostic and treatment strategies for obesity and related cardiometabolic diseases. Although obesity detrimentally impacts oral health causative linkages and associations have not been conclusively made between periodontitis and obesity. The most intriguing connections between adipobiology and saliva (or salivary glands) have emerged from unexpected quarters. It was recently reported that adiponectin, resistin and visfatin (adipose tissue-derived signaling proteins collectively termed adipokines) are found in saliva and that their amount correlates with that of circulating level of these adipokines. These observations suggest that the introduction of salivary determinations of adipokines may contribute to the study of pathogenesis of various obesity-related diseases. Receptors for adipokines and obesity-related hormones, especially for polypeptide Y (PYY (3-36)), in the mouth and in particular the taste buds, may be a primary signal for satiety. This observation offers new avenues for investigating the physiology of satiety along with potential treatment strategies for obesity. Another unexpected finding, and to date unrelated to obesity - the transplantation of adipose-derived stromal cells has the potential to restore salivary gland function after their destruction by radiation therapy. Adipobiology 2012; 4: 51-58.