Key Laboratory of Anti-Inflammatory and Immunopharmacology, Ministry of Education, Department of Pharmacology, Anhui Medical University, Hefei 230032, Anhui, China; Department of Pharmacy, The First Affiliated Hospital of Anhui Medical University, Hefei 230032, Anhui, China.
Key Laboratory of Anti-Inflammatory and Immunopharmacology, Ministry of Education, Department of Pharmacology, Anhui Medical University, Hefei 230032, Anhui, China.
Pharmacol Rep. 2019 Apr;71(2):319-329. doi: 10.1016/j.pharep.2018.12.008. Epub 2018 Dec 21.
The increased influx of free fatty acids (FFAs) into the kidney is a risk factor for diabetes nephropathy (DN). In the present study we investigated the effects of astragaloside IV (AS-IV) on FFA-induced lipid accumulation, oxidative stress, and activation of TGF-β1 signaling in human glomerular mesangial cells (HMCs).
A DN model was induced in Sprague Dawley rats by the administration of a high-fat diet and streptozocin, and HMCs were stimulated with palmitate. Lipid accumulation and FFA uptake were detected using Oil Red O and BODIPY™ FL C staining, respectively. The expression levels of TGF-β1, p-Smad2/3, FN, Col4 A1, NOX4, p22phox, and CD36 were evaluated by western blotting or immunofluorescence/immunohistochemistry. The level of reactive oxygen species (ROS) was detected using 2',7'-dichlorofluorescein diacetate and dihydroethidium.
Exposure to palmitate induced marked lipid accumulation in HMCs, whereas co-treatment with AS-IV significantly attenuated this phenomenon. Moreover, AS-IV suppressed palmitate-induced expression of TGF-β1, p-Smad2/3, FN, Col4 A1, NOX4, and p22phox, in addition to ROS production. Notably, AS-IV reduced the palmitate-induced expression of CD36 in HMCs and DN rats. Treatment of HMCs with the CD36 inhibitor, sulfo-N-succinimidyl oleate (SSO), significantly attenuated FFA uptake, oxidative stress, and fibrosis. Nevertheless, the combined use of SSO and AS-IV did not enhance the efficacy.
AS-IV inhibited palmitate-induced HMCs oxidative stress and fibrosis via the downregulation of CD36 expression, mediating FFA uptake and lipid accumulation.
进入肾脏的游离脂肪酸（FFAs）增加是糖尿病肾病（DN）的一个风险因素。在本研究中，我们研究了黄芪甲苷 IV（AS-IV）对人肾小球系膜细胞（HMCs）中 FFAs 诱导的脂质积累、氧化应激和 TGF-β1 信号转导激活的影响。
通过给予高脂肪饮食和链脲佐菌素诱导 Sprague Dawley 大鼠发生 DN 模型，并使用棕榈酸刺激 HMCs。使用油红 O 和 BODIPY™ FL C 染色分别检测脂质积累和 FFA 摄取。通过 Western blot 或免疫荧光/免疫组化评估 TGF-β1、p-Smad2/3、FN、Col4A1、NOX4、p22phox 和 CD36 的表达水平。使用 2'，7'-二氯荧光素二乙酸和二氢乙啶检测活性氧（ROS）的水平。
棕榈酸暴露诱导 HMCs 中明显的脂质积累，而 AS-IV 共同处理显著减弱了这种现象。此外，AS-IV 抑制了棕榈酸诱导的 TGF-β1、p-Smad2/3、FN、Col4A1、NOX4 和 p22phox 的表达，以及 ROS 的产生。值得注意的是，AS-IV 降低了 HMCs 和 DN 大鼠中 CD36 的表达。用 CD36 抑制剂磺基-N-琥珀酰亚胺辛酯（SSO）处理 HMCs，可显著减轻 FFA 摄取、氧化应激和纤维化。然而，SSO 和 AS-IV 的联合使用并没有增强疗效。
AS-IV 通过下调 CD36 的表达抑制棕榈酸诱导的 HMCs 氧化应激和纤维化，介导 FFA 摄取和脂质积累。
