| First Author | Yoshida R | Year | 2021 |
| Journal | J Neurochem | Volume | 158 |
| Issue | 2 | Pages | 233-245 |
| PubMed ID | 33319361 | Mgi Jnum | J:352979 |
| Mgi Id | MGI:6728314 | Doi | 10.1111/jnc.15268 |
| Citation | Yoshida R, et al. (2021) Phosphatidylinositol-3 kinase mediates the sweet suppressive effect of leptin in mouse taste cells. J Neurochem 158(2):233-245 |
| abstractText | Leptin is known to selectively suppress neural and taste cell responses to sweet compounds. The sweet suppressive effect of leptin is mediated by the leptin receptor Ob-Rb, and the ATP-gated K(+) (KATP ) channel expressed in some sweet-sensitive, taste receptor family 1 member 3 (T1R3)-positive taste cells. However, the intracellular transduction pathway connecting Ob-Rb to KATP channel remains unknown. Here we report that phosphoinositide 3-kinase (PI3K) mediates leptin's suppression of sweet responses in T1R3-positive taste cells. In in situ taste cell recording, systemically administrated leptin suppressed taste cell responses to sucrose in T1R3-positive taste cells. Such leptin's suppression of sucrose responses was impaired by co-administration of PI3K inhibitors (wortmannin or LY294002). In contrast, co-administration of signal transducer and activator of transcription 3 inhibitor (Stattic) or Src homology region 2 domain-containing phosphatase-2 inhibitor (SHP099) had no effect on leptin's suppression of sucrose responses, although signal transducer and activator of transcription 3 and Src homology region 2 domain-containing phosphatase-2 were expressed in T1R3-positive taste cells. In peeled tongue epithelium, phosphatidylinositol (3,4,5)-trisphosphate production and phosphorylation of AKT by leptin were immunohistochemically detected in some T1R3-positive taste cells but not in glutamate decarboxylase 67-positive taste cells. Leptin-induced phosphatidylinositol (3,4,5)-trisphosphate production was suppressed by LY294002. Thus, leptin suppresses sweet responses of T1R3-positive taste cells by activation of Ob-Rb-PI3K-KATP channel pathway. |
