PPARγ/p38MAPK信号通路调控结核分枝杆菌感染的巨噬细胞焦亡机制

Mechanisms of PPARγ/p38MAPK signaling pathway in regulating macrophage pyroptosis with Mycobacterium tuberculosis infection

    摘要
  • 摘要:
    目的 探究过氧化物酶体增殖物激活受体γ(PPARγ)/p38丝裂原活化蛋白激酶(p38MAPK)通路是否调控结核分枝杆菌(MTB)感染巨噬细胞焦亡及其抗菌能力。
    方法 培养Raw264.7巨噬细胞, 分为对照组、MTB组、抑制PPARγ组及过表达PPARγ组。免疫荧光染色检测巨噬细胞中PPARγ、磷酸化p38MAPK(p-p38MAPK)、GSDME、NOD样受体热蛋白结构域包含蛋白3(NLRP3)蛋白水平。蛋白质印迹法(WB)检测巨噬细胞GSDME、NLRP3蛋白水平。逆转录定量聚合酶链式反应检测巨噬细胞中PPARγ、p-p38MAPK、GSDME、NLRP3的mRNA水平。检测巨噬细胞荷菌量。
    结果 与对照组相比, MTB组巨噬细胞中PPARγ(6.67±0.59 vs. 0.99±0.02, 4.98±0.31 vs. 1.00±0.02)、p-p38MAPK(5.61±0.44 vs. 0.99±0.01, 4.82±0.43 vs. 0.98±0.02)蛋白及mRNA水平增加(P＜0.05), 细胞焦亡相关蛋白GSDME(4.38±0.27 vs. 0.98±0.02, 3.59±0.29 vs. 0.99±0.02)、NLRP3(5.61±0.16 vs. 1.01±0.02, 4.65±0.33 vs. 1.00±0.02)蛋白及mRNA水平增加(P＜0.05), 巨噬细胞中菌落数量增加(P＜0.05)；与MTB组相比, 抑制PPARγ组巨噬细胞中PPARγ、p-p38MAPK、GSDME、NLRP3蛋白及mRNA水平减少(P＜0.05), 巨噬细胞菌落数量减少(P＜0.05)；与MTB组相比, 过表达PPARγ组巨噬细胞中GSDME、NLRP3蛋白及mRNA水平增加(P＜0.05), 巨噬细胞菌落数量减少(P＜0.05)。
    结论 PPARγ/p38MAPK通路可激活MTB感染巨噬细胞焦亡并增强其抗菌能力。

     

    Abstract:
    OBJECTIVE To investigate whether the peroxisome proliferator-activated receptor γ (PPARγ)/p38 mitogen-activated protein kinase (p38MAPK) pathway regulates pyroptosis in Mycobacterium tuberculosis (MTB)-infected macrophages and their antibacterial ability.
    METHODS Raw264.7 macrophages were cultured and divided into the control group, MTB group, PPARγ-inhibited group and PPARγ-overexpressed group. Immunofluorescence staining was used to detect the protein levels of PPARγ, phosphorylated p38MAPK (p-p38MAPK), GSDME and NOD-like receptor pyrin domain-containing protein 3 (NLRP3) in macrophages. Western blotting (WB) was employed to measure the protein levels of GSDME and NLRP3 in macrophages. Reverse transcription quantitative polymerase chain reaction was used to detect the mRNA levels of PPARγ, p-p38MAPK, GSDME and NLRP3 in macrophages. The bacterial load in macrophages was also assessed.
    RESULTS Compared with the control group, the MTB group showed increased protein and mRNA levels of PPARγ (6.67±0.59 vs. 0.99±0.02, 4.98±0.31 vs. 1.00±0.02) and p-p38MAPK (5.61±0.44 vs. 0.99±0.01, 4.82±0.43 vs. 0.98±0.02) (P < 0.05). Additionally, there was an increase in the protein and mRNA levels of pyroptosis-related proteins GSDME (4.38±0.27 vs. 0.98±0.02, 3.59±0.29 vs. 0.99±0.02) and NLRP3 (5.61±0.16 vs. 1.01±0.02, 4.65±0.33 vs. 1.00±0.02) (P < 0.05), as well as an increase in the number of bacterial colonies in macrophages (P < 0.05). Compared with the MTB group, the PPARγ-inhibited group exhibited decreased protein and mRNA levels of PPARγ, p-p38MAPK, GSDME and NLRP3 in macrophages (P < 0.05), along with a reduction in the number of macrophage bacterial colonies (P < 0.05). In contrast, compared with the MTB group, the PPARγ-overexpressed group showed increased protein and mRNA levels of GSDME and NLRP3 in macrophages (P < 0.05), but a decrease in the number of macrophage bacterial colonies (P < 0.05).
    CONCLUSION The PPARγ/p38MAPK pathway can activate pyroptosis in MTB-infected macrophages and enhance their antibacterial ability.

     

    • HTML全文
    • 参考文献(27)
    • 相关文章
    • 施引文献
  • 资源附件(0)

/

返回文章
返回
下载中心