Cai Wei-Feng, Chen Qi-Cong, Ni Qian, Liu Li, Liu Qiang, Yi Yan-Kui, Jiang Cui-Ping, Shen Chun-Yan
School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China; Guangdong Provincial Key Laboratory of Chinese Medicine Pharmaceutics, Southern Medical University, Guangzhou, 510515, China; Guangdong Basic Research Center of Excellence for Integrated Traditional and Western Medicine for Qingzhi Diseases, Guangzhou, 510515, China.
School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, 510515, China; Guangdong Provincial Key Laboratory of Chinese Medicine Pharmaceutics, Southern Medical University, Guangzhou, 510515, China; Guangdong Basic Research Center of Excellence for Integrated Traditional and Western Medicine for Qingzhi Diseases, Guangzhou, 510515, China.
J Ethnopharmacol. 2025 May 28;348:119890. doi: 10.1016/j.jep.2025.119890. Epub 2025 Apr 26.
Citrus aurantium L. var. amara Engl. is a folk medicine and dietary supplement popularly used in alleviating indigestion due to food retention and obesity. p-Synephrine, a principal proto-alkaloid in Citrus aurantium L. var. amara Engl., is extensively utilized due to its numerous benefits, particularly its potential to ameliorate obesity. Previous studies of our research demonstrated that p-synephrine had the potential to alleviate insulin resistance (IR) and liver lipid accumulation caused by high-fat diet (HFD), as well as enlargement of cells in adipose tissue. However, the effects of p-synephrine in ameliorating non-alcoholic fatty liver disease (NAFLD) were still unclear.
To explore the effects of p-synephrine on HFD-induced NAFLD and its mechanisms.
NAFLD mice were developed by HFD feeding and treated with p-synephrine once a day for 21 weeks. The protective effects of p-synephrine against NAFLD and its mechanisms were evaluated by OGTT, ITT, biochemical index measurements, H&E, immunofluorescence, Sirius red staining, oil red O staining, immunohistochemistry, RT-qPCR, Western blot, network pharmacology, and molecular docking assays.
The results of network pharmacology suggested that AMPK-α1 might be the core target, and AMPK and insulin signaling pathways might be the key regulatory pathways of p-synephrine to alleviate NAFLD. Molecular docking confirmed AMPK-α1 as a probable direct molecular target. p-Synephrine significantly reduced HFD-induced weight gain of the body, liver, and iWAT. It improved glucose tolerance, insulin tolerance and lipid metabolism disorders caused by HFD. Serum levels of NO, TNF-α, and IL-6 in NAFLD mice were suppressed. AST, ALT, and HYP levels in serum and liver were inhibited. Morphological observation showed p-synephrine alleviated hepatic steatosis and fibrosis. p-Synephrine administration also significantly inhibited hepatic de novo lipogenesis (DNL), as evidenced by its regulation of non-esterified fatty acid (NEFA) and TG contents, as well as SREBP-1c, FASN, and ACC1 mRNA expression levels. p-Synephrine also reversed HFD-induced histopathological changes in iWAT, promoted iWAT browning by increasing UCP1 and PGC-1α expression. Simultaneously, p-synephrine intervention markedly increased phosphorylation levels of IRS-1, PI3K, and Akt, and protein expression of GLUT-4 in iWAT and liver. Expression of TNF-α, IL-6, and IL-1β and NF-κB activation in iWAT and liver were attenuated through the treatment of p-synephrine. Further assays showed that p-synephrine intervention potently regulated AMPK pathway in iWAT and liver of mice.
This investigation proposed that p-synephrine had the potential to ameliorate HFD-induced NAFLD by regulating liver-adipose axis through AMPK/NF-κB pathway.
酸橙是一种民间药物和膳食补充剂，常用于缓解食积和肥胖引起的消化不良。对羟基福林是酸橙中的一种主要原生物碱，因其具有多种益处，特别是其改善肥胖的潜力而被广泛应用。我们之前的研究表明，对羟基福林有可能减轻高脂饮食（HFD）引起的胰岛素抵抗（IR）和肝脏脂质积累，以及脂肪组织中细胞的增大。然而，对羟基福林改善非酒精性脂肪性肝病（NAFLD）的作用仍不清楚。
探讨对羟基福林对HFD诱导的NAFLD的影响及其机制。
通过HFD喂养建立NAFLD小鼠模型，并每天用对羟基福林治疗21周。通过口服葡萄糖耐量试验（OGTT）、胰岛素耐量试验（ITT）、生化指标测量、苏木精-伊红（H&E）染色、免疫荧光、天狼星红染色、油红O染色、免疫组织化学、逆转录-定量聚合酶链反应（RT-qPCR）、蛋白质免疫印迹法（Western blot）、网络药理学和分子对接试验，评估对羟基福林对NAFLD的保护作用及其机制。
网络药理学结果表明，AMPK-α1可能是核心靶点，AMPK和胰岛素信号通路可能是对羟基福林减轻NAFLD的关键调控通路。分子对接证实AMPK-α1为可能的直接分子靶点。对羟基福林显著降低了HFD诱导的体重、肝脏和腹股沟白色脂肪组织（iWAT）的增加。它改善了HFD引起的葡萄糖耐量、胰岛素耐量和脂质代谢紊乱。NAFLD小鼠血清中一氧化氮（NO）、肿瘤坏死因子-α（TNF-α）和白细胞介素-6（IL-6）水平受到抑制。血清和肝脏中的天冬氨酸转氨酶（AST）、丙氨酸转氨酶（ALT）和羟脯氨酸（HYP）水平也受到抑制。形态学观察表明，对羟基福林减轻了肝脏脂肪变性和纤维化。对羟基福林给药还显著抑制了肝脏从头脂肪生成（DNL），这通过其对非酯化脂肪酸（NEFA）和甘油三酯（TG）含量以及固醇调节元件结合蛋白-1c（SREBP-1c）、脂肪酸合酶（FASN）和乙酰辅酶A羧化酶1（ACC1）mRNA表达水平的调节得以证明。对羟基福林还逆转了HFD诱导的iWAT组织病理学变化，并通过增加解偶联蛋白1（UCP1）和过氧化物酶体增殖物激活受体γ共激活因子1α（PGC-1α）的表达促进iWAT褐变。同时，对羟基福林干预显著增加了iWAT和肝脏中胰岛素受体底物-1（IRS-1）、磷脂酰肌醇-3激酶（PI3K）和蛋白激酶B（Akt）的磷酸化水平，以及葡萄糖转运蛋白4（GLUT-4）的蛋白表达。通过对羟基福林治疗，iWAT和肝脏中TNF-α、IL-6和IL-1β的表达以及核因子κB（NF-κB）的激活减弱。进一步的试验表明，对羟基福林干预有效调节了小鼠iWAT和肝脏中的AMPK通路。
本研究表明，对羟基福林有可能通过AMPK/NF-κB通路调节肝脏-脂肪轴，改善HFD诱导的NAFLD。
