[Research progress in taste G protein-coupled receptors and dental caries]

Recent studies have demonstrated that the functions of taste G protein-coupled receptor (GPCR) extend far beyond gustation. These receptors are widely distributed in oral tissues, participating in local immune regulation and maintenance of oral microbial homeostasis. As chemosensory receptors, taste GPCR modulate individual sensitivity to sweet and bitter stimuli, thereby influencing dietary preference, sugar intake, and susceptibility to dental caries. In addition, they play crucial roles in microbial signal recognition and the preservation of ecological balance within the oral cavity. Downregulation or dysfunction of these receptors may arise from intrinsic or extrinsic factors such as genetic polymorphisms, inflammatory stimuli, head and neck squamous cell carcinoma, or radio-chemotherapy. These alterations can compromise GPCR-mediated mucosal immune defenses and promote a pathological shift in microbial community composition, ultimately leading to oral dysbiosis as well as imbalanced demineralization and remineralization of dental hard tissues. This article reviews the research progress on the structure and function of sweet and bitter GPCR, and clarifies their association with dental caries from the perspective of oral ecology and microbiota regulation. Future studies focusing on structure-based receptor targeting are expected to provide a solid theoretical foundation for precise therapeutic strategies such as "taste-guided anti-inflammation" and "taste-mediated microbiota modulation" and to expand their translational prospects in clinical dentistry.