Mao Shi-Hao, Feng Dan-Dan, Wang Xi, Zhi Yi-Hui, Lei Shu, Xing Xi, Jiang Rong-Lin, Wu Jian-Nong
Department of Intensive Care Unit, The First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310006, Zhejiang Province, China.
Key Laboratory of Digestive Pathophysiology of Zhejiang Province, The First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310053, Zhejiang Province, China.
World J Clin Cases. 2021 Dec 6;9(34):10451-10463. doi: 10.12998/wjcc.v9.i34.10451.
Sepsis is a major medical challenge. Magnolol is an active constituent of that improves tissue function and exerts strong anti-endotoxin and anti-inflammatory effects, but the mechanism by which it reduces intestinal inflammation in sepsis is yet unclear.
To assess the protective effect of magnolol on intestinal mucosal epithelial cells in sepsis and elucidate the underlying mechanisms.
Enzyme-linked immunosorbent assay was used to measure tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, and regulated on activation, normal T-cell expressed and secreted (RANTES) levels in serum and ileal tissue in animal studies. The histopathological changes of the ileal mucosa in different groups were observed under a microscope. Cell Counting Kit-8 and cell permeability assays were used to determine the concentration of drug-containing serum that did not affect the activity of Caco2 cells but inhibited lipopolysaccharide (LPS)-induced decrease in permeability. Immunofluorescence and Western blot assays were used to detect the levels of RANTES, inhibitor of nuclear factor kappa-B kinase β (IKKβ), phosphorylated IKKβ (p-IKKβ), inhibitor of nuclear factor kappa-B kinase α (IκBα), p65, and p-p65 proteins in different groups .
In rats treated with LPS by intravenous tail injection in the presence or absence of magnolol, magnolol inhibited the expression of proinflammatory cytokines, IL-1β, IL-6, and TNF-α in a dose-dependent manner. In addition, magnolol suppressed the production of RANTES in LPS-stimulated sepsis rats. Moreover, studies suggested that magnolol inhibited the increase of p65 nucleation, thereby markedly downregulating the production of the phosphorylated form of IKKβ in LPS-treated Caco2 cells. Specifically, magnolol inhibited the translocation of the transcription factor nuclear factor-kappa B (NF-κB) from the cytosol into the nucleus and down-regulated the expression level of the chemokine RANTES in LPS-stimulated Caco2 cells.
Magnolol down-regulates RANTES levels by inhibiting the LPS/NF-κB signaling pathways, thereby suppressing IL-1β, IL-6, and TNF-α expression to alleviate the mucosal barrier dysfunction in sepsis.
脓毒症是一项重大的医学挑战。厚朴酚是其有效成分，可改善组织功能并发挥强大的抗内毒素和抗炎作用，但它减轻脓毒症肠道炎症的机制尚不清楚。
评估厚朴酚对脓毒症肠道黏膜上皮细胞的保护作用，并阐明其潜在机制。
在动物研究中，采用酶联免疫吸附测定法检测血清和回肠组织中肿瘤坏死因子-α（TNF-α）、白细胞介素-1β（IL-1β）、IL-6以及活化调节正常T细胞表达和分泌因子（RANTES）的水平。在显微镜下观察不同组回肠黏膜的组织病理学变化。使用细胞计数试剂盒-8和细胞通透性测定法来确定不影响Caco2细胞活性但能抑制脂多糖（LPS）诱导的通透性降低的含药血清浓度。采用免疫荧光和蛋白质印迹法检测不同组中RANTES、核因子κB激酶β（IKKβ）、磷酸化IKKβ（p-IKKβ）、核因子κB激酶α抑制因子（IκBα）、p65和磷酸化p65蛋白的水平。
在存在或不存在厚朴酚的情况下，通过尾静脉注射LPS处理的大鼠中，厚朴酚以剂量依赖性方式抑制促炎细胞因子IL-1β、IL-6和TNF-α的表达。此外，厚朴酚抑制LPS刺激的脓毒症大鼠中RANTES的产生。而且，研究表明厚朴酚抑制p65核转运增加，从而显著下调LPS处理的Caco2细胞中IKKβ磷酸化形式的产生。具体而言，厚朴酚抑制转录因子核因子-κB（NF-κB）从细胞质向细胞核的转位，并下调LPS刺激的Caco2细胞中趋化因子RANTES的表达水平。
厚朴酚通过抑制LPS/NF-κB信号通路下调RANTES水平，从而抑制IL-1β、IL-6和TNF-α表达，以减轻脓毒症中的黏膜屏障功能障碍。
