Impact of a long-term high-glucose environment on pro-inflammatory responses in macrophages stimulated with lipopolysaccharide.
Impact of a long-term high-glucose environment on pro-inflammatory responses in macrophages stimulated with lipopolysaccharide.
复制标题
长期高血糖环境对脂多糖刺激的巨噬细胞促炎反应的影响。
DOI：
10.1007/s00210-021-02137-8
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发表时间：
2021
期刊：
影响因子：
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通讯作者：
Hattori Y.
中科院分区：
文献类型：
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作者：
Suzuki T;Yamashita S;Hattori K;Matsuda N;Hattori Y.
累积的证据已经确定，巨噬细胞协调炎症反应，这对胰岛素抵抗性肥胖和2型糖尿病的发病机制至关重要。在本研究中，我们研究了高血糖对炎症刺激下巨噬细胞促炎反应的影响。为了进行该研究，将RAW 264.7巨噬细胞在正常（5.5mM）或高葡萄糖（22或40 mM）条件下培养7天，并用脂多糖（LPS）刺激。当巨噬细胞用LPS刺激时，长期暴露于高糖显著增强促炎细胞因子的产生，包括肿瘤坏死因子-α、白细胞介素（IL）-1β和IL-6。LPS诱导的诱导型一氧化氮（NO）合酶（iNOS）的表达和NO的产生增加也显着增强长期暴露的巨噬细胞高糖。用N-乙酰-L-半胱氨酸（一种广泛使用的含巯基的抗氧化剂）治疗可减弱LPS诱导的巨噬细胞中促炎细胞因子产生、iNOS表达和NO产生的上调。当使用荧光染料5-（和-6）-氯甲基-2 ′，7 ′-二氯荧光素二乙酸酯（乙酰酯）观察细胞内活性氧（ROS）时，发现用LPS刺激巨噬细胞后ROS产生显著增加，并且这种增加的ROS产生在长期高糖条件下加剧。在长期高糖条件下，LPS诱导的磷酸化核因子-κB（NF-κB）（一种调节许多促炎基因的转录因子）易位到细胞核中。总之，目前的结果表明，长期高葡萄糖环境可以增强LPS刺激的巨噬细胞中NF-κB的活化，可能是由于过量的ROS产生，从而导致巨噬细胞促炎反应增加。
Cumulative evidence has established that macrophages orchestrate inflammatory responses that crucially contribute to the pathogenesis of insulin-resistant obesity and type 2 diabetes. In the present study, we examined the impact of hyperglycemia on macrophage pro-inflammatory responses under an inflammatory stimulus. To conduct this study, RAW264.7 macrophages were cultured under normal- (5.5 mM) or high-glucose (22 or 40 mM) conditions for 7 days and stimulated with lipopolysaccharide (LPS). Long-term exposure to high glucose significantly enhanced the increase in the production of pro-inflammatory cytokines, including tumor necrosis-α, interleukin (IL)-1β, and IL-6, when macrophages were stimulated with LPS. The LPS-induced increases in inducible nitric oxide (NO) synthase (iNOS) expression and NO production were also significantly enhanced by long-term exposure of macrophages to high glucose. Treatment withN-acetyl-l-cysteine, a widely used thiol-containing antioxidant, blunted the enhancement of the LPS-induced upregulation of pro-inflammatory cytokine production, iNOS expression, and NO production in macrophages. When intracellular reactive oxygen species (ROS) were visualized using the fluorescence dye 5-(and-6)-chloromethyl-2′,7′-dichlorofluorescein diacetate, acetyl ester, a significant increase in ROS generation was found after stimulation of macrophages with LPS, and this increased ROS generation was exacerbated under long-term high-glucose conditions. LPS-induced translocation of phosphorylated nuclear factor-κB (NF-κB), a transcription factor regulating many pro-inflammatory genes, into the nucleus was promoted under long-term high-glucose conditions. Altogether, the present results indicate that a long-term high-glucose environment can enhance activation of NF-κB in LPS-stimulated macrophages possibly due to excessive ROS production, thereby leading to increased macrophage pro-inflammatory responses.