Xiong Xuekai, Pangemanan Jemima, Kiperman Tali, Sun Zuoming, Paul Antoni, Yechoor Vijay, Ma Ke
Department of Diabetes Complications & Metabolism, Beckman Research Institute of City of Hope, Duarte, CA 91010, USA.
Department of Molecular Imaging & Therapy, Beckman Research Institute of City of Hope, Duarte, CA 91010, USA.
bioRxiv. 2025 Sep 2:2025.08.28.672947. doi: 10.1101/2025.08.28.672947.
The circadian clock orchestrates adipocyte development and lipid remodeling, with its disruption leading to the development of obesity and insulin resistance. Here we demonstrate that the flavonoid compound naringenin displays clock modulatory activity via RORα that suppresses adipocyte lipid storage while promoting browning. In adipogenic progenitors, naringenin activates RORα with induction of clock gene expression to promote circadian clock oscillation with protective effect against cytokine-induced dampening. The clock-enhancing properties of naringenin suppressed lipogenesis in mature adipocytes together with induction of browning characteristics. The inhibitory effect of naringenin on lipogenesis was dependent on clock modulation as it was abolished in RORα-deficient adipocytes. We further show that naringenin administration in vivo up-regulated RORα expression with clock gene induction together with browning of subcutaneous beige fat depot, resulting reduced fat mass and body weight. Naringenin treatment in vivo also lowered plasma glucose and free fatty acid levels, with markedly enhanced insulin signaling in adipose depots and skeletal muscle. Collectively, our findings uncover a new clock-activating mechanism of action in mediating the metabolic benefits of naringenin, suggesting its potential as a natural supplement for anti-obesity and metabolic disease interventions.
昼夜节律时钟协调脂肪细胞的发育和脂质重塑,其功能紊乱会导致肥胖和胰岛素抵抗的发生。在此,我们证明黄酮类化合物柚皮素通过RORα发挥时钟调节活性,抑制脂肪细胞脂质储存,同时促进脂肪褐变。在脂肪生成祖细胞中,柚皮素通过诱导时钟基因表达来激活RORα,促进昼夜节律时钟振荡,对细胞因子诱导的抑制具有保护作用。柚皮素增强时钟的特性抑制了成熟脂肪细胞中的脂肪生成,并诱导了脂肪褐变特征。柚皮素对脂肪生成的抑制作用依赖于时钟调节,因为在RORα缺陷的脂肪细胞中这种作用消失了。我们进一步表明,体内给予柚皮素可上调RORα表达,诱导时钟基因表达,并使皮下米色脂肪库褐变,从而减少脂肪量和体重。体内柚皮素治疗还降低了血浆葡萄糖和游离脂肪酸水平,显著增强了脂肪库和骨骼肌中的胰岛素信号。总的来说,我们的研究结果揭示了一种新的时钟激活作用机制,介导了柚皮素的代谢益处,表明其作为抗肥胖和代谢疾病干预天然补充剂的潜力。