Knockout of the murine prostaglandin EP2 receptor impairs osteoclastogenesis in vitro
Knockout of the murine prostaglandin EP2 receptor impairs osteoclastogenesis in vitro
复制标题
DOI：
10.1210/en.141.6.2054
复制
发表时间：
2000-06-01
期刊：
影响因子：
4.8
通讯作者：
Raisz, LG
中科院分区：
文献类型：
--
作者：
Li, XD;Okada, Y;Raisz, LG
前列腺素E-2(PGE(2))体外刺激破骨细胞样抗酒石酸酸性磷酸酶阳性多核细胞(TRAP+MNC)的形成。这种作用可能是由两种PGE(2)受体介导的腺酰环化酶的刺激所致，分别命名为EP2和EP4。我们使用EP2受体被破坏的小鼠的细胞来测试它在TRAP+MNC形成中的作用。在C57BL/6 x 129/SvEv背景下培育EP2杂合子(I)小鼠，产生纯合子缺失型(EP2-/-)和野生型(EP2+/+)小鼠。前列腺素E(2)、甲状旁腺素或1，25二羟基维生素D可增加7天培养的EP+/+小鼠骨髓细胞TRAP+MNC。在EP2-/-动物的培养中，对PGE(2)、PTH和1，25二羟基维生素D的反应分别降低了86%、58%和50%。选择性EP受体拮抗剂(EP(4)RA)进一步抑制EP2+/+和EP2-/-培养中TRAP+MNC的形成。在脾和颅骨成骨细胞共培养中，EP2-/-小鼠的成骨细胞和脾细胞对PGE(2)或PTH的反应性降低了92%或85%，仅来自EP2-/-小鼠的成骨细胞降低了88%或68%，仅来自EP2-/-小鼠的脾细胞对PGE(2)或PTH的反应降低了58%或35%。PGE(2)可使EP2+/+小鼠成骨细胞和骨髓细胞培养上清液中核因子受体激活剂(NF)-kB配体(RANKL)信使RNA的表达增加一倍，而对EP2-/-小鼠骨髓细胞中RANKL信使RNA的表达无明显影响。用RANKL和巨噬细胞集落刺激因子培养的脾细胞产生TRAP+MNC。PGE(2)可增加EP2+/+小鼠脾细胞培养上清液中TRAP+MNC的数量，但对EP2-/-小鼠脾细胞培养上清液中TRAP+MNC的数量无明显影响。EP、RA对脾细胞PGE(2)反应无明显影响。PGE(2)可降低EP2+/+小鼠脾细胞培养上清中粒细胞-巨噬细胞集落刺激因子信使RNA的表达，但对EP2-/-小鼠脾细胞无明显影响。这些数据表明前列腺素EP2受体在体外破骨细胞样细胞的形成中起作用。EP2-/-小鼠的一个主要缺陷似乎是成骨细胞刺激破骨细胞形成的能力。此外，在EP2-/-小鼠中，破骨细胞系细胞对前列腺素E的反应似乎存在缺陷。
Prostaglandin E-2 (PGE(2)) stimulates the formation of osteoclastlike tartrate-resistant acid phosphatase-positive multinucleated cells (TRAP + MNC) in vitro. This effect likely results from stimulation of adenylyl cyclase, which is mediated by two PGE(2) receptors, designated nated EP2 and EP4. We used cells from mice in which the EP2 receptor had been disrupted to test its role in the formation of TRAP + MNC. EP2 heterozygous (I)mice in a C57BL/6 x 129/SvEv background were bred to produce homozygous null (EP2 -/-) and wild-type (EP2 +/+) mice. PGE(2), PTH, or 1,25 dihydroxyvitamin D increased TRAP+ MNC in 7-day cultures of bone marrow cells from EP, +/+ mice. In cultures from EP2 -/- animals, responses to PGE(2), PTH, and 1,25 dihydroxyvitamin D were reduced by 86%, 58%, and 50%, respectively. A selective EP, receptor antagonist (EP(4)RA) further inhibited TRAP+ MNC formation in both EP2 +/+ and EP2 -/- cultures. In cocultures of spleen and calvarial osteoblastic cells, the response to PGE(2) or PTH was reduced by 92% or 85% when both osteoblastic cells and spleen cells were from EP2 -/- mice, by 88% or 68% when only osteoblastic cells were from EP2 -/- mice and by 58% or 35% when only spleen cells were from EP2 -/- mice. PGE(2) increased receptor activator of nuclear factor (NF)-kB ligand (RANKL) messenger RNA expression in osteoblastic and bone marrow cell cultures from EP2 +/+ mice a-fold but had little effect on cells from EP2 -/- mice. Spleen cells cultured with RANKL and macrophage colony stimulating factor produced TRAP + MNC. PGE(2) increased the number of TRAP + MNC in spleen cell cultures from EP2 +/+ mice but not in cultures from EP2 -/- mice. EP,RA had no effect on the PGE(2) response in spleen cell cultures. PGE(2) decreased the expression of messenger RNA for granulocyte-macrophage colony stimulating factor in spleen cell cultures from EP2 +/+ mice but had little effect on cells from EP2 -/- mice. These data demonstrate that the prostaglandin EP2 receptor plays a role in the formation of osteoclast-like cells in vitro. A major defect in EP2 -/- mice appears to be in the capacity of osteoblastic cells to stimulate osteoclast formation. In addition, there appears to be a defect in the response of cells of the osteoclastic lineage to PGE, in EP2 -/- mice.