Healthy Aging Korean Medical Research Center, School of Korean Medicine, Pusan National University, Yangsan 50612, Korea.
Division of Longevity and Biofunctional Medicine, School of Korean Medicine, Pusan National University, Yangsan 50612, Korea.
Int J Mol Sci. 2019 Sep 27;20(19):4801. doi: 10.3390/ijms20194801.
Wolf (PCW) is an edible, pharmaceutical mushroom with remarkable biological properties including anti-tumor, anti-inflammation, anti-oxidation, anti-ageing, and anti-diabetic effects. In the current study, we investigated the effects of PCW extract on hepatic steatosis under in vitro and in vivo conditions, and elucidated the underlying mechanisms. In this study, a mixture of HepG2 cells treated with free fatty acid (FFA)-palmitic and oleic acid-and high-fat diet (HFD)-fed obese mice were used; in this background, the triglyceride (TG) levels in HepG2 cells and mice liver were measured, and the expression levels of genes associated with lipogenesis, fatty acid oxidation, endoplasmic reticulum (ER) stress, and autophagy were determined. Treatment of HepG2 cells with FFA enhanced intracellular TG levels in HepG2 cells, but co-treatment with PCW significantly attenuated the TG levels. Notably, PCW significantly enhanced the phosphorylation of AMP-activated protein kinase (AMPK), acetyl-CoA carboxylase (ACC), and sterol regulatory element-binding protein-1c (SREBP-1c) in FFA-treated HepG2 cells. PCW downregulated the expression of lipogenesis-related genes, but upregulated the expression of genes associated with fatty acid oxidation. Further, PCW inhibited FFA-induced expression of ER stress markers and induced autophagy proteins. However, inhibition of AMPK significantly attenuated the beneficial effects of PCW in HepG2 cells. Moreover, PCW efficiently decreased HFD-induced hepatic TG accumulation in vivo and increased the phosphorylation of hepatic AMPK. Three compounds present in PCW including poricoic acid, pachymic acid, and ergosterol, significantly decreased FFA-induced increase in intracellular TG levels, consistent with increased AMPK phosphorylation, suggesting that poricoic acid, pachymic acid, and ergosterol are responsible for PCW-mediated amelioration of hepatic steatosis. Taken together, these results demonstrated that PCW ameliorates hepatic steatosis through the regulation of lipid metabolism, inhibition of ER stress, and activation of autophagy in an AMPK-dependent manner. This suggested that PCW can be potentially used for the treatment of hepatic steatosis.
云芝（PCW）是一种可食用的药用蘑菇，具有显著的生物学特性，包括抗肿瘤、抗炎、抗氧化、抗衰老和抗糖尿病作用。在本研究中，我们在体外和体内条件下研究了 PCW 提取物对肝脂肪变性的影响，并阐明了其潜在机制。在这项研究中，使用了混合的 HepG2 细胞（用游离脂肪酸（FFA）-棕榈酸和油酸处理）和高脂肪饮食（HFD）喂养的肥胖小鼠；在此背景下，测量 HepG2 细胞和小鼠肝脏中的甘油三酯（TG）水平，并确定与脂肪生成、脂肪酸氧化、内质网（ER）应激和自噬相关的基因的表达水平。FFA 处理 HepG2 细胞可增强细胞内 TG 水平，但 PCW 共同处理可显著降低 TG 水平。值得注意的是，PCW 显著增强了 FFA 处理的 HepG2 细胞中 AMP 激活蛋白激酶（AMPK）、乙酰辅酶 A 羧化酶（ACC）和固醇调节元件结合蛋白-1c（SREBP-1c）的磷酸化。PCW 下调了与脂肪生成相关的基因的表达，但上调了与脂肪酸氧化相关的基因的表达。此外，PCW 抑制了 FFA 诱导的 ER 应激标志物的表达并诱导了自噬蛋白。然而，AMPK 的抑制显著减弱了 PCW 在 HepG2 细胞中的有益作用。此外，PCW 有效地减少了体内 HFD 诱导的肝 TG 积累，并增加了肝 AMPK 的磷酸化。PCW 中的三种化合物包括多孔菌酸、薄孔酸和麦角固醇，显著降低了 FFA 诱导的细胞内 TG 水平升高，与 AMPK 磷酸化增加一致，表明多孔菌酸、薄孔酸和麦角固醇是 PCW 介导的肝脂肪变性改善的原因。总之，这些结果表明，PCW 通过调节脂质代谢、抑制 ER 应激和激活自噬来改善肝脂肪变性，这是一种 AMPK 依赖性的方式。这表明 PCW 可潜在用于治疗肝脂肪变性。
