Department of Anatomy-Histology-Embryology, School of Medicine, University of Patras, 26504 Patras, Greece.
Department of Pathology, School of Medicine, University of Patras, 26504 Patras, Greece.
Int J Mol Sci. 2022 Nov 28;23(23):14899. doi: 10.3390/ijms232314899.
Data on animals emphasize the importance of the neuronal glucagon-like peptide-1 (GLP-1) receptor (GLP-1R) for feeding suppression, although it is unclear whether astrocytes participate in the transduction of anorectic GLP-1R-dependent signals. In humans, the brain circuitry underlying these effects remains insufficiently investigated. The present study aimed to explore GLP-1R protein expression in the human hypothalamus and its correlation with body mass index (BMI). Sections of hypothalamus from 28 autopsy cases, 11 with normal weight (BMI < 25 kg/m2) and 17 with non-normal weight (BMI ≥ 25 kg/m2), were examined using immunohistochemistry and double immunofluorescence labeling. Prominent GLP-1R immunoexpression was detected in neurons of several hypothalamic nuclei, including paraventricular, supraoptic, and infundibular nuclei; the lateral hypothalamic area (LH); and basal forebrain nuclei. Interestingly, in the LH, GLP-1R was significantly decreased in individuals with BMI ≥ 25 kg/m2 compared with their normal weight counterparts (p = 0.03). Furthermore, GLP-1R was negatively correlated (τb = −0.347, p = 0.024) with BMI levels only in the LH. GLP-1R extensively colocalized with the anorexigenic and antiobesogenic neuropeptide nucleobindin-2/nesfatin-1 but not with the astrocytic marker glial fibrillary acidic protein. These data suggest a potential role for GLP-1R in the regulation of energy balance in the human hypothalamus. In the LH, an appetite- and reward-related brain region, reduced GLP-1R immunoexpression may contribute to the dysregulation of homeostatic and/or hedonic feeding behavior. Possible effects of NUCB2/nesfatin-1 on central GLP-1R signaling require further investigation.
动物研究数据强调了神经元胰高血糖素样肽-1(GLP-1)受体(GLP-1R)在抑制摄食方面的重要性,尽管尚不清楚星形胶质细胞是否参与传递致厌食的 GLP-1R 依赖信号。在人类中,这些作用的大脑回路仍未得到充分研究。本研究旨在探索人类下丘脑 GLP-1R 蛋白表达及其与体重指数(BMI)的相关性。使用免疫组织化学和双重免疫荧光标记法检查了 28 例尸检病例的下丘脑切片,其中 11 例体重正常(BMI<25kg/m2),17 例体重异常(BMI≥25kg/m2)。在几个下丘脑核,包括室旁核、视上核和漏斗核;外侧下丘脑区域(LH);和基底前脑核中检测到明显的 GLP-1R 免疫表达。有趣的是,在 LH 中,与体重正常的对照组相比,BMI≥25kg/m2 的个体的 GLP-1R 显著减少(p=0.03)。此外,GLP-1R 仅与 LH 中的 BMI 水平呈负相关(τb=-0.347,p=0.024)。GLP-1R 与厌食和抗肥胖神经肽核结合蛋白 2/nesfatin-1 广泛共定位,但与星形胶质细胞标志物胶质纤维酸性蛋白不共定位。这些数据表明 GLP-1R 在人类下丘脑调节能量平衡中可能发挥作用。在 LH 中,作为与食欲和奖赏相关的脑区,GLP-1R 免疫表达减少可能导致稳态和/或享乐性摄食行为失调。NUCB2/nesfatin-1 对中枢 GLP-1R 信号的可能影响需要进一步研究。