Department of Infection, Affiliated Hospital of Guizhou Medical University, No. 28, Guiyi Street, Guiyang, 550001, Guizhou, China.
School of Clinical Medicine, Guizhou Medical University, Guiyang, 55000, Guizhou, China.
J Transl Med. 2022 Mar 14;20(1):128. doi: 10.1186/s12967-022-03343-5.
Nonalcoholic steatohepatitis (NASH) is one of the most common liver diseases and has no safe and effective drug for treatment. We have previously reported the function of blueberry, but the effective monomer and related molecular mechanism remain unclear.
The monomer of blueberry was examined by ultra performance liquid chromatography-mass spectrometry (UPLC-MS). The NASH cell model was constructed by exposing HepG2 cells to free fatty acids. The NASH mouse model was induced by a high-fat diet for 12 weeks. NASH cell and mouse models were treated with different concentrations of blueberry monomers. The molecular mechanism was studied by Oil Red O staining, ELISA, enzyme activity, haematoxylin-eosin (H&E) staining, immunohistochemistry, immunofluorescence, western blot, RNA sequencing, and qRT-PCR.
We identified one of the main monomer of blueberry as tectorigenin (TEC). Cyanidin-3-O glucoside (C3G) and TEC could significantly inhibit the formation of lipid droplets in steatosis hepatocytes, and the effect of TEC on the formation of lipid droplets was significantly higher than that of C3G. TEC can promote cell proliferation and inhibit the release of inflammatory mediators in NASH cell model. Additionally, TEC administration provided a protective role against high-fat diets induced lipid damage, and suppressed lipid accumulation. In NASH mouse model, TEC can activate autophagy, inhibit pyroptosis and the release of inflammatory mediators. In NASH cell model, TEC inhibited pyroptosis by stimulating autophagy. Then, small RNA sequencing revealed that TEC up-regulated the expression of tRF-47-58ZZJQJYSWRYVMMV5BO (tRF-47). The knockdown of tRF-47 blunted the beneficial effects of TEC on NASH in vitro, including inhibition of autophagy, activation of pyroptosis and release of inflammatory factors. Similarly, suppression of tRF-47 promoted the lipid injury and lipid deposition in vivo.
These results demonstrated that tRF-47-mediated autophagy and pyroptosis plays a vital role in the function of TEC to treat NASH, suggesting that TEC may be a promising drug for the treatment of NASH.
非酒精性脂肪性肝炎（NASH）是最常见的肝脏疾病之一，目前尚无安全有效的治疗药物。我们之前报道过蓝莓的功能，但有效单体及相关分子机制尚不清楚。
采用超高效液相色谱-质谱联用（UPLC-MS）法检测蓝莓的单体。用游离脂肪酸孵育 HepG2 细胞构建 NASH 细胞模型。用高脂肪饮食诱导 12 周构建 NASH 小鼠模型。用不同浓度的蓝莓单体处理 NASH 细胞和小鼠模型。通过油红 O 染色、ELISA、酶活性、苏木精-伊红（H&E）染色、免疫组织化学、免疫荧光、Western blot、RNA 测序和 qRT-PCR 研究分子机制。
我们鉴定出蓝莓的主要单体之一为紫檀芪（TEC）。矢车菊素-3-O-葡萄糖苷（C3G）和 TEC 可显著抑制脂肪变性肝细胞中脂滴的形成，且 TEC 对脂滴形成的抑制作用明显强于 C3G。TEC 可促进 NASH 细胞模型中细胞的增殖并抑制炎症介质的释放。此外，TEC 给药可防止高脂肪饮食引起的脂质损伤，并抑制脂质积累。在 NASH 小鼠模型中，TEC 可通过激活自噬抑制焦亡和炎症介质的释放。然后，小 RNA 测序显示 TEC 上调 tRF-47-58ZZJQJYSWRYVMMV5BO（tRF-47）的表达。tRF-47 敲低削弱了 TEC 在体外对 NASH 的有益作用，包括抑制自噬、激活焦亡和释放炎症因子。同样，抑制 tRF-47 促进了体内的脂质损伤和脂质沉积。
这些结果表明，tRF-47 介导的自噬和焦亡在 TEC 治疗 NASH 的功能中起关键作用，提示 TEC 可能是治疗 NASH 的一种有前途的药物。
