Sun Ji Su, Yang Dong Joo, Kinyua Ann W, Yoon Seul Gi, Seong Je Kyung, Kim Juwon, Moon Seok Jun, Shin Dong Min, Choi Yun-Hee, Kim Ki Woo
Department of Oral Biology, Yonsei University College of Dentistry, Seoul, Korea.
Department of Applied Biological Science, BK21 FOUR, Yonsei University College of Dentistry, Seoul, Korea.
J Clin Invest. 2021 Jan 4;131(1). doi: 10.1172/JCI138107.
Dysfunction of primary cilia is related to dyshomeostasis, leading to a wide range of disorders. The ventromedial hypothalamus (VMH) is known to regulate several homeostatic processes, but those modulated specifically by VMH primary cilia are not yet known. In this study, we identify VMH primary cilia as an important organelle that maintains energy and skeletal homeostasis by modulating the autonomic nervous system. We established loss-of-function models of primary cilia in the VMH by either targeting IFT88 (IFT88-KOSF-1) using steroidogenic factor 1-Cre (SF-1-Cre) or injecting an adeno-associated virus Cre (AAV-Cre) directly into the VMH. Functional impairments of VMH primary cilia were linked to decreased sympathetic activation and central leptin resistance, which led to marked obesity and bone-density accrual. Obesity was caused by hyperphagia, decreased energy expenditure, and blunted brown fat function and was also associated with insulin and leptin resistance. The effect of bone-density accrual was independent of obesity, as it was caused by decreased sympathetic tone resulting in increased osteoblastic and decreased osteoclastic activities in the IFT88-KOSF-1 and VMH primary cilia knockdown mice. Overall, our current study identifies VMH primary cilia as a critical hypothalamic organelle that maintains energy and skeletal homeostasis.
初级纤毛功能障碍与内环境稳态失调相关,会导致多种疾病。已知腹内侧下丘脑(VMH)可调节多种内环境稳态过程,但具体由VMH初级纤毛调节的过程尚不清楚。在本研究中,我们确定VMH初级纤毛是一种重要的细胞器,通过调节自主神经系统来维持能量和骨骼稳态。我们通过使用类固醇生成因子1-Cre(SF-1-Cre)靶向IFT88(IFT88-KOSF-1)或直接将腺相关病毒Cre(AAV-Cre)注射到VMH中,建立了VMH初级纤毛功能丧失模型。VMH初级纤毛的功能障碍与交感神经激活降低和中枢瘦素抵抗有关,这导致明显的肥胖和骨密度增加。肥胖是由食欲亢进、能量消耗减少、棕色脂肪功能减弱引起的,还与胰岛素和瘦素抵抗有关。骨密度增加的影响与肥胖无关,因为它是由交感神经张力降低导致的,在IFT88-KOSF-1和VMH初级纤毛敲低小鼠中,成骨细胞活性增加,破骨细胞活性降低。总体而言,我们目前的研究确定VMH初级纤毛是维持能量和骨骼稳态的关键下丘脑细胞器。