Cell Biology and Neuroscience, Rowan University School of Osteopathic Medicine, Stratford, NJ 08084, USA.
Department of Biologic and Materials Sciences & Prosthodontics, School of Dentistry, University of Michigan, Ann Arbor, MI 48109, USA.
Int J Mol Sci. 2023 Mar 2;24(5):4833. doi: 10.3390/ijms24054833.
Sensory receptors across the entire tongue are engaged during eating. However, the tongue has distinctive regions with taste (fungiform and circumvallate) and non-taste (filiform) organs that are composed of specialized epithelia, connective tissues, and innervation. The tissue regions and papillae are adapted in form and function for taste and somatosensation associated with eating. It follows that homeostasis and regeneration of distinctive papillae and taste buds with particular functional roles require tailored molecular pathways. Nonetheless, in the chemosensory field, generalizations are often made between mechanisms that regulate anterior tongue fungiform and posterior circumvallate taste papillae, without a clear distinction that highlights the singular taste cell types and receptors in the papillae. We compare and contrast signaling regulation in the tongue and emphasize the Hedgehog pathway and antagonists as prime examples of signaling differences in anterior and posterior taste and non-taste papillae. Only with more attention to the roles and regulatory signals for different taste cells in distinct tongue regions can optimal treatments for taste dysfunctions be designed. In summary, if tissues are studied from one tongue region only, with associated specialized gustatory and non-gustatory organs, an incomplete and potentially misleading picture will emerge of how lingual sensory systems are involved in eating and altered in disease.
在进食过程中,整个舌头上的感觉受体都被激活。然而,舌头上有独特的味觉区域(菌状和轮廓乳头)和非味觉区域(丝状乳头),它们由专门的上皮组织、结缔组织和神经支配组成。组织区域和乳突的形态和功能适应于与进食相关的味觉和躯体感觉。因此,具有特定功能的独特乳突和味蕾的内稳态和再生需要特定的分子途径。尽管如此,在化学感觉领域,人们通常将调节前舌菌状和后舌轮廓乳头的机制进行概括,而没有明确区分突出乳突中独特的味觉细胞类型和受体。我们比较和对比了舌部的信号调节,并强调 Hedgehog 途径及其拮抗剂是前舌和后舌味觉和非味觉乳突信号差异的主要范例。只有更多地关注不同舌部区域不同味觉细胞的作用和调节信号,才能设计出针对味觉功能障碍的最佳治疗方法。总之,如果仅从一个舌部区域研究组织,并结合相关的特殊味觉和非味觉器官,那么对舌部感觉系统如何参与进食以及在疾病中如何改变的理解将是不完整的,甚至可能产生误导。