NLRP3 promotes autophagy of urate crystals phagocytized by human osteoblasts.
NLRP3 promotes autophagy of urate crystals phagocytized by human osteoblasts.
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DOI：
10.1186/ar4365
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发表时间：
2013-11-01
影响因子：
4.9
通讯作者：
Poubelle PE
中科院分区：
文献类型：
--
作者：
Allaeys I;Marceau F;Poubelle PE
慢性痛风骨组织中存在的尿酸钠 (MSU) 微晶可以被非专业吞噬细胞（如表达 NLRP3（核苷酸结合域和含有受体蛋白 3 家族的富含亮氨酸重复区域）的成骨细胞 (OB) 摄取）。众所周知，MSU 可激活专业吞噬细胞中的 NLRP3 炎症小体。我们已经确定了 NLRP3 在 MSU 刺激的人类 OB 中与自噬结合的新作用。使用共聚焦显微镜研究了体外培养的正常人 OB 吞噬 MSU 微晶的能力。随后评估了矿化和基质金属蛋白酶活性，并通过使用信号抑制剂、磷酸激酶阵列和小干扰 RNA 破译了吞噬作用的调节事件。采用配对或非配对t检验和单因素方差分析进行统计，然后进行多重比较检验。大多数 OB 将 MSU 内化到液泡中。该过程依赖于 PI3K、蛋白激酶 C (PKC) 和脾酪氨酸激酶 (Syk) 的信号传导，但独立于 Src 激酶。同时，MSU 降低蛋白激酶 TOR（雷帕霉素靶标）和 p70S6K 的磷酸化。 MSU 激活微管相关蛋白轻链 3 (LC3)-I 裂解为 LC3-II，并且 MSU 微晶涂有 GFP 标记的 LC3。然而，MSU 刺激的 OB 中的自噬绝对需要吞噬过程。我们发现 MSU 上调 NLRP3，从而正向控制 OB 中 MSU 自噬体的形成。 MSU 不会增加 OB 的死亡和晚期凋亡，但会减少其增殖，同时降低其矿化能力并增加其基质金属蛋白酶活性。 MSU 微晶存在于慢性痛风的骨基质中，可激活 OB 中的吞噬作用和 NLRP3 依赖性自噬，但在永久性自噬体中保持完整，同时解除对 OB 功能的调节。
Monosodium urate (MSU) microcrystals present in bone tissues of chronic gout can be ingested by nonprofessional phagocytes like osteoblasts (OBs) that express NLRP3 (nucleotide-binding domain and leucine-rich repeat region containing family of receptor protein 3). MSU is known to activate NLRP3 inflammasomes in professional phagocytes. We have identified a new role for NLRP3 coupled to autophagy in MSU-stimulated human OBs. Normal human OBs cultured in vitro were investigated for their capacity for phagocytosis of MSU microcrystals by using confocal microscopy. Subsequent mineralization and matrix metalloproteinase activity were evaluated, whereas regulatory events of phagocytosis were deciphered by using signaling inhibitors, phosphokinase arrays, and small interfering RNAs. Statistics were carried out by using paired or unpaired t tests, and the one-way ANOVA, followed by multiple comparison test. Most of the OBs internalized MSU in vacuoles. This process depends on signaling via PI3K, protein kinase C (PKC), and spleen tyrosine kinase (Syk), but is independent of Src kinases. Simultaneously, MSU decreases phosphorylation of the protein kinases TOR (target of rapamycin) and p70S6K. MSU activates the cleavage of microtubule-associated protein light chain 3 (LC3)-I into LC3-II, and MSU microcrystals are coated with GFP-tagged LC3. However, MSU-stimulated autophagy in OBs absolutely requires the phagocytosis process. We find that MSU upregulates NLRP3, which positively controls the formation of MSU-autophagosomes in OBs. MSU does not increase death and late apoptosis of OBs, but reduces their proliferation in parallel to decreasing their competence for mineralization and to increasing their matrix metalloproteinase activity. MSU microcrystals, found locally encrusted in the bone matrix of chronic gout, activate phagocytosis and NLRP3-dependent autophagy in OBs, but remain intact in permanent autophagosomes while deregulating OB functions.
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影响因子：
11.1
作者：
He C;Klionsky DJ
通讯作者：
Klionsky DJ
影响因子：
4
作者：
Akahoshi, T;Nagaoka, T;Kondo, H
通讯作者：
Kondo, H
DOI：
10.1073/pnas.78.11.6858
发表时间：
1981-01-01
期刊：
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA-BIOLOGICAL SCIENCES
影响因子：
--
作者：
AMES, BN;CATHCART, R;HOCHSTEIN, P
通讯作者：
HOCHSTEIN, P
影响因子：
4.4
作者：
Bouchard, L;de Médicis, R;Poubelle, PE
通讯作者：
Poubelle, PE
影响因子：
11.4
作者：
Dupont, Nicolas;Jiang, Shanya;Deretic, Vojo
通讯作者：
Deretic, Vojo