In addition to their stimulatory action on neuronal differentiation and survival, a variety of neurotrophic factors, such as nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and ciliary neurotrophic factor, exert metabotrophic effects, including improvement of glucose, lipid and energy homeostasis. It was recently reported that plasma levels of both NGF and BDNF are reduced in patients with advanced metabolic syndrome and with acute coronary syndromes, and that NGF tissue content is decreased in human atherosclerotic coronary arteries. Since NGF and BDNF are synthesized, stored, and released by submandibular salivary glands, we investigated the structure and function of these glands. Here we present our scintigraphic and echographic results of submandibular glands of patients with advanced stage of metabolic syndrome: (i) scintigraphic analysis using the radiotracer (99m)Tc-pertechnetate showed an inhibition of salivary gland excretory activity, and (ii) echographic evaluation revealed a parenchymal destruction and a prominent fibrosis of the glands. Both suggestive for the involvement of submandibular glands in decreased secretion of NGF and BDNF as implicated in the pathogenesis of metabolic syndrome.
Biomedical Reviews 2007; 18: 65-67.