Sulforaphane induces lipophagy through the activation of AMPK-mTOR-ULK1 pathway signaling in adipocytes.
Sulforaphane induces lipophagy through the activation of AMPK-mTOR-ULK1 pathway signaling in adipocytes.
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DOI：
10.1016/j.jnutbio.2022.109017
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发表时间：
2022-08
影响因子：
5.6
通讯作者：
Taketani, Yutaka
中科院分区：
文献类型：
--
作者：
Masuda, Masashi;Yoshida-Shimizu, Risa;Mori, Yuki;Ohnishi, Kohta;Adachi, Yuichiro;Sakai, Maiko;Kabutoya, Serina;Ohminami, Hirokazu;Yamanaka-Okumura, Hisami;Yamamoto, Hironori;Miyazaki, Makoto;Taketani, Yutaka
噬脂作用是选择性自噬的一种形式，可降解脂肪组织和肝脏中的脂滴（LD）。化学治疗剂异硫氰酸萝卜硫素（SFN）通过激活对脂肪酸敏感的脂肪酶和白色脂肪细胞的布朗宁来促进脂解。然而，关于SFN介导的自噬调节脂肪细胞脂解的细节仍不清楚。在这项研究中，我们研究了SFN对喂食高脂饮食（HFD）或对照脂肪饮食的小鼠附睾脂肪中自噬的影响，以及对分化的3 T3-L1细胞中自噬的分子机制的影响。Western blotting结果显示，SFN处理3 T3-L1脂肪细胞后，脂化LC 3（LC 3-II）的蛋白表达被诱导，LC 3-II是自噬底物。此外，SFN增加了喂食HFD的小鼠附睾脂肪中LC 3-II蛋白的表达。免疫荧光显示，SFN诱导的LC 3表达与3 T3-L1脂肪细胞中的LDs和喂食HFD的小鼠脂肪细胞中最丰富的脂肪细胞特异性蛋白perilipin共定位。接下来，我们使用mCherry-EGFP-LC 3和GFP-LC 3-RFP-LC 3 ΔG探针证实SFN激活分化的3 T3-L1细胞中的自噬通量。此外，我们使用蛋白质印迹法研究了3 T3-L1脂肪细胞中SFN诱导自噬的机制。ATG 5敲低部分阻断了SFN诱导的成熟3 T3-L1脂肪细胞中脂肪酸从LD的释放。SFN时间依赖性地诱导分化的3 T3-L1细胞中AMPK的磷酸化、mTOR的去磷酸化和ULK 1的磷酸化。综上所述，这些结果表明，SFN可能通过AMPK-mTOR-ULK 1信号通路引起脂肪吞噬，导致脂肪细胞的部分脂解。
Lipophagy, a form of selective autophagy, degrades lipid droplet (LD) in adipose tissue and the liver. The chemotherapeutic isothiocyanate sulforaphane (SFN) contributes to lipolysis through the activation of hormone-sensitive lipase and the browning of white adipocytes. However, the details concerning the regulation of lipolysis in adipocytes by SFN-mediated autophagy remain unclear. In this study, we investigated the effects of SFN on autophagy in the epididymal fat of mice fed a high-fat diet (HFD) or control-fat diet and on the molecular mechanisms of autophagy in differentiated 3T3-L1 cells. Western blotting revealed that the protein expression of lipidated LC3 (LC3-II), an autophagic substrate, was induced after 3T3-L1 adipocytes treatment with SFN. In addition, SFN increased the LC3-II protein expression in the epididymal fat of mice fed an HFD. Immunofluorescence showed that the SFN-induced LC3 expression was co-localized with LDs in 3T3-L1 adipocytes and with perilipin, the most abundant adipocyte-specific protein, in adipocytes of mice fed an HFD. Next, we confirmed that SFN activates autophagy flux in differentiated 3T3-L1 cells using the mCherry-EGFP-LC3 and GFP-LC3-RFP-LC3ΔG probe. Furthermore, we examined the induction mechanisms of autophagy by SFN in 3T3-L1 adipocytes using western blotting. ATG5 knockdown partially blocked the SFN-induced release of fatty acids from LDs in mature 3T3-L1 adipocytes. SFN time-dependently elicited the phosphorylation of AMPK, the dephosphorylation of mTOR, and the phosphorylation of ULK1 in differentiated 3T3-L1 cells. Taken together, these results suggest that SFN may provoke lipophagy through AMPK-mTOR-ULK1 pathway signaling, resulting in partial lipolysis of adipocytes.
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影响因子：
2.4
作者：
Imi Y;Yabiki N;Abuduli M;Masuda M;Yamanaka-Okumura H;Taketani Y
通讯作者：
Taketani Y
影响因子：
21.3
作者：
通讯作者：
--
影响因子：
64.8
作者：
Ichimura, Y;Kirisako, T;Ohsumi, Y
通讯作者：
Ohsumi, Y
影响因子：
10.5
作者：
Itoh, K;Wakabayashi, N;Yamamoto, M
通讯作者：
Yamamoto, M
影响因子：
4.8
作者：
Jain, Ashish;Lamark, Trond;Johansen, Terje
通讯作者：
Johansen, Terje