College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, China.
Key Laboratory of Animal Diseases and Environmental Hazards of Sichuan Province, Sichuan Agriculture University, Wenjiang, Chengdu, 611130, China.
Biol Trace Elem Res. 2019 May;189(1):157-171. doi: 10.1007/s12011-018-1458-z. Epub 2018 Jul 30.
At present, no reports are focused on fluoride-induced hepatic inflammatory responses in human beings and animals. This study aimed to investigate the mRNA and protein levels of inflammatory cytokines and signaling molecules for evaluating the effect of different doses (0, 12, 24, and 48 mg/kg) of sodium fluoride (NaF) on inflammatory reaction in the mouse liver by using methods of experimental pathology, quantitative real-time polymerase chain reaction (qRT-PCR), and western blot analysis. We found that NaF in excess of 12 mg/kg caused the hepatic inflammatory responses, and the results showed that NaF activated the mitogen-activated protein kinases (MAPKs) signaling pathway by markedly increasing (p < 0.01 or p < 0.05) mRNA and protein levels of apoptosis signal-regulating kinase 1 (ASK1), mitogen-activated protein kinase kinases 1/2 (MEK1/2), extracellular signal-regulated protein kinases 1/2 (Erk1/2), mitogen-activated protein kinase kinases 4/7 (MEK4/7), c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (p38) and mitogen-activated protein kinase kinases 3/6 (MEK3/6), and the nuclear factor-kappa B (NF-κB) signaling pathway by increasing (p < 0.01 or p < 0.05) the production of NF-κB and inhibitor of nuclear factor kappa-B kinase subunit beta (IKK-β) and reducing (p < 0.01 or p < 0.05) the production of the inhibitory kappa B (IκB). Thus, NaF that caused the hepatic inflammatory responses was characterized by increasing (p < 0.01 or p < 0.05) the production of pro-inflammatory mediators such as interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8), monocyte chemotactic protein 1 (MCP-1), and cyclooxygenase-2 (COX-2) via the activation of MAPKs and NF-κB pathways, and by significantly inhibiting (p < 0.01 or p < 0.05) the production of anti-inflammatory mediators including interleukin-4 (IL-4) and transforming growth factor beta (TGF-β).
目前,尚无关于氟化物诱导人类和动物肝脏炎症反应的报道。本研究旨在通过实验病理学、实时定量聚合酶链反应 (qRT-PCR) 和 Western blot 分析方法,研究不同剂量(0、12、24 和 48 mg/kg)的氟化钠(NaF)对小鼠肝脏炎症反应的影响,评估炎症细胞因子和信号分子的 mRNA 和蛋白水平。我们发现,超过 12 mg/kg 的 NaF 会引起肝炎症反应,结果表明,NaF 通过显著增加凋亡信号调节激酶 1(ASK1)、丝裂原活化蛋白激酶激酶 1/2(MEK1/2)、细胞外信号调节蛋白激酶 1/2(Erk1/2)、丝裂原活化蛋白激酶激酶 4/7(MEK4/7)、c-Jun N 末端激酶(JNK)、p38 丝裂原活化蛋白激酶(p38)和丝裂原活化蛋白激酶激酶 3/6(MEK3/6)的 mRNA 和蛋白水平,激活丝裂原活化蛋白激酶(MAPK)信号通路,同时增加核因子-κB(NF-κB)信号通路中 NF-κB 和核因子κB 激酶亚单位β(IKK-β)的产生,减少抑制性κB(IκB)的产生,从而引起炎症反应。因此,NaF 引起的肝炎症反应的特征是通过激活 MAPK 和 NF-κB 通路,增加促炎介质如白细胞介素 1β(IL-1β)、白细胞介素 6(IL-6)、白细胞介素 8(IL-8)、单核细胞趋化蛋白 1(MCP-1)和环氧化酶 2(COX-2)的产生(p<0.01 或 p<0.05),同时显著抑制抗炎介质如白细胞介素 4(IL-4)和转化生长因子β(TGF-β)的产生(p<0.01 或 p<0.05)。