MAPK信号通路在绝经后骨质疏松症骨重建失衡中的作用及干预研究进展
Research Progress on the Role and Intervention of the MAPK Signaling Pathway in the Imbalance of Bone Remodeling in Postmenopausal Osteoporosis
DOI: 10.12677/acm.2025.1541204, PDF, HTML, XML,   
作者: 颜雍霖*, 孙承霞, 黄明雄, 王孝杰:成都中医药大学临床医学院,四川 成都;高永翔#:成都中医药大学附属医院风湿免疫科,四川 成都
关键词: MAPK信号通路骨重建绝经后骨质疏松症作用机理MAPK Signaling Pathway Bone Remodeling Postmenopausal Osteoporosis Mechanism of Action
摘要: 绝经后骨质疏松症(PMOP)是一种与雌激素缺乏密切相关的代谢性骨病,其核心特征为骨重建失衡。丝裂原活化蛋白激酶(MAPK)信号通路在这一过程中发挥着关键作用。本文系统阐述了MAPK信号通路的组成、激活机制,及其在PMOP骨重建失衡中的作用。MAPK信号通路包含ERK、JNK、p38MAPK和ERK5等分支,雌激素缺乏及细胞因子网络失衡可激活该通路。在PMOP中,MAPK信号通路对成骨细胞的增殖、分化、矿化以及骨髓间充质干细胞的成脂分化产生不同影响,同时也调节破骨细胞的分化、活化和骨吸收功能,并与OPG/RANKL/RANK系统相互作用。此外,本文还对现有干预策略进行了评估,指出当前研究的局限性,并提出基于多组学技术的精准治疗是未来的发展方向,旨在为开发高效低毒的PMOP治疗方案提供理论依据。
Abstract: Postmenopausal osteoporosis (PMOP) is a metabolic bone disease closely related to estrogen deficiency, and its core feature is the imbalance of bone remodeling. The mitogen-activated protein kinase (MAPK) signaling pathway plays a crucial role in this process. This article systematically expounds on the composition and activation mechanism of the MAPK signaling pathway, as well as its role in the imbalance of bone remodeling in PMOP. The MAPK signaling pathway includes branches such as ERK, JNK, p38MAPK, and ERK5. Estrogen deficiency and the imbalance of the cytokine network can activate this pathway. In PMOP, the MAPK signaling pathway has different effects on the proliferation, differentiation, and mineralization of osteoblasts, as well as the adipogenic differentiation of bone marrow mesenchymal stem cells. It also regulates the differentiation, activation, and bone resorption function of osteoclasts and interacts with the OPG/RANKL/RANK system. In addition, this article evaluates the existing intervention strategies, points out the limitations of current research, and proposes that precision medicine based on multi-omics technology is the future development direction, aiming to provide a theoretical basis for the development of highly effective and low-toxicity treatment regimens for PMOP.
文章引用:颜雍霖, 孙承霞, 黄明雄, 王孝杰, 高永翔. MAPK信号通路在绝经后骨质疏松症骨重建失衡中的作用及干预研究进展[J]. 临床医学进展, 2025, 15(4): 2483-2493. https://doi.org/10.12677/acm.2025.1541204

1. 引言

绝经后骨质疏松症(Postmenopausal Osteoporosis, PMOP),与雌激素缺乏息息相关的代谢性骨病,据统计全球约23.1%绝经女性受其威胁[1]。PMOP的核心病理特征是骨重建失衡,表现为破骨细胞(OC)骨吸收活性显著增强,而成骨细胞(OB)骨形成能力代偿不足[2]。最新研究显示,雌激素缺乏通过多种机制打破骨代谢平衡:首先,雌激素分泌减少导致核因子κB受体活化因子配体(RANKL)与骨保护素(OPG)比值失衡,使OC分化增加2~3倍[3];其次,雌激素受体(ER)信号减弱解除对炎症因子(如IL-1β、TNF-α)的抑制,形成慢性低度炎症微环境[4];更重要的是,这些病理过程均与丝裂原活化蛋白激酶(MAPK)信号通路的异常激活密切相关[5]

MAPK通路作为细胞外信号向核内传递的关键枢纽,包含ERK、JNK和p38MAPK三条经典分支[6]。在PMOP中,雌激素缺乏通过ERα失活导致MAPK通路负调控解除[7]。同时,IL-1β和TNF-α诱导骨髓基质细胞中RANKL表达需要p38丝裂原活化蛋白激酶(MAPK)通路激活,抑制p38MAPK通路会减少IL-1β和TNF-α诱导的RANKL mRNA表达,且阻断p38信号通路会部分抑制IL-1β和TNF-α诱导的破骨细胞生成[8]。本文系统梳理MAPK通路在PMOP中的分子机制,评估现有干预策略的优缺点,并提出基于多组学技术的精准治疗方向,为开发高效低毒的PMOP治疗方案提供理论依据。

2. MAPK信号通路的组成

MAPK信号通路包含多条分支,在细胞生理活动中至关重要。其中,ERK1/2通路因生长因子刺激,经一系列激酶激活,调节细胞增殖分化;JNK通路于细胞应激、炎症时,通过特定激酶级联反应,参与细胞凋亡与炎症;p38MAPK通路在类似情况下,调控细胞凋亡、炎症及细胞周期;ERK5通路虽研究少,但受生长因子等刺激后,对细胞增殖、存活有影响[9]

2.1. 细胞外调节蛋白激酶(ERK)1/2通路

ERK1/2通路是MAPK信号通路中最早被发现和研究的一条通路。其上游激活物主要包括生长因子受体、Ras蛋白等[10]。当细胞受到生长因子、细胞因子等刺激时,受体酪氨酸激酶磷酸化,招募接头蛋白Grb2和鸟苷酸交换因子SOS,SOS促进Ras蛋白从无活性的GDP结合形式转变为有活性的GTP结合形式[11]。活化的Ras激活Raf蛋白(一种MAPKKK),Raf磷酸化并激活MEK1/2 (一种MAPKK),MEK1/2进而磷酸化ERK1/2,使其激活[12]。激活的ERK1/2可进入细胞核,磷酸化多种转录因子,如Elk-1、c-Fos等,调节基因表达,促进细胞增殖、分化等过程[13]

2.2. c-Jun氨基末端激酶(JNK)通路

JNK通路的激活主要与细胞应激反应、炎症因子刺激等有关[14]。其上游激活物包括肿瘤坏死因子-α (TNF-α)、白细胞介素-1β (IL-1β)等细胞因子受体,以及紫外线、氧化应激等应激刺激[15]。这些刺激通过一系列信号转导分子,激活混合谱系激酶(MLK)等MAPKKK,MLK磷酸化并激活MKK4/7 (一种MAPKK),MKK4/7再磷酸化JNK,使其激活[16]。激活的JNK可磷酸化c-Jun等转录因子,调节相关基因表达,参与细胞凋亡、炎症反应等过程[17]

2.3. p38丝裂原活化蛋白激酶(p38MAPK)通路

p38MAPK通路同样在细胞应激反应、炎症过程中发挥重要作用[18]。其上游激活物与JNK通路类似,包括多种细胞因子、应激刺激等[19]。激活的p38MAPK通路通过一系列信号转导分子,激活ASK1等MAPKKK,ASK1磷酸化并激活MKK3/6 (一种MAPKK),MKK3/6再磷酸化p38MAPK,使其激活[20]。激活的p38MAPK可磷酸化多种转录因子,如ATF2、Elk-1等,调节基因表达,参与细胞凋亡、炎症反应、细胞周期阻滞等过程[21]

2.4. ERK5通路

ERK5通路相对研究较少,其激活主要与生长因子、机械应力等刺激有关[22]。当细胞受到刺激时,MEKK2/3等MAPKKK被激活,MEKK2/3磷酸化并激活MEK5 (一种MAPKK),MEK5再磷酸化ERK5,使其激活[23]。激活的ERK5可进入细胞核,磷酸化转录因子,如MEF2C等,调节基因表达,参与细胞增殖、存活等过程[24]

3. MAPK信号通路的激活机制

MAPK信号通路的激活通常由细胞表面受体接收外界信号开始[25]。不同的刺激信号通过相应的受体激活特定的MAPK信号通路[26]。例如,生长因子与受体酪氨酸激酶结合,激活ERK1/2通路;细胞因子与细胞因子受体结合,激活JNK和p38MAPK通路;机械应力等刺激则可激活ERK5通路[27]。在信号转导过程中,MAPK信号通路通过三级激酶级联反应将信号逐级放大。MAPKKK被上游信号激活后,磷酸化并激活MAPKK,MAPKK再磷酸化并激活MAPK [28]。MAPK的激活是通过其苏氨酸(T)和酪氨酸(Y)残基的双磷酸化实现的,不同的MAPK亚族成员其双磷酸化位点之间的氨基酸残基(X)不同,如ERK为Thr-Glu-Tyr,p38为Thr-Gly-Tyr,JNK为Thr-Pro-Tyr [29]。双磷酸化的MAPK具有活性,可进一步磷酸化下游靶蛋白,调节细胞功能[30]。此外,MAPK信号通路还受到多种负反馈调节机制的调控,以维持信号转导的平衡和稳定。例如,磷酸酶可去磷酸化MAPK及其上游激酶,使其失活;一些蛋白可与MAPK信号通路中的分子相互作用,抑制信号转导[31]

4. MAPK信号通路在PMOP骨重建失衡中的作用

骨重建失衡涉及多种细胞,主要包括破骨细胞、成骨细胞和骨细胞,以下将分为MAPK信号通路对成骨细胞的作用和MAPK信号通路对破骨细胞的作用分别讲述。

4.1. MAPK信号通路对成骨细胞的作用

4.1.1. 对成骨细胞增殖、分化和矿化的影响

成骨细胞在骨形成过程中起着关键作用,其增殖、分化和矿化能力直接影响骨量的增加[32]。研究表明,MAPK信号通路对成骨细胞的这些生物学过程具有重要调节作用[33]。ERK1/2通路在成骨细胞增殖和早期分化中发挥重要作用。多种生长因子,如胰岛素样生长因子-1 (IGF-1)、骨形态发生蛋白(BMPs)等,可通过激活ERK1/2通路促进成骨细胞增殖[34]。在成骨细胞分化早期,ERK1/2通路的激活可上调核心结合因子α1(Runx2)等成骨相关转录因子的表达和活性,促进成骨细胞向成熟阶段分化[35]。然而,ERK1/2通路过度激活或持续激活可能抑制成骨细胞的矿化能力[36]

p38MAPK通路在成骨细胞分化和矿化过程中起重要作用[37]。机械应力、BMPs等刺激可激活p38MAPK通路,促进成骨细胞分化和矿化[38]。p38MAPK通路的激活可通过磷酸化Runx2等转录因子,增强其活性,促进成骨细胞特异性基因的表达,如碱性磷酸酶(ALP)、骨钙素(OCN)等,从而促进成骨细胞分化和矿化[37]。Qi等人[39]的研究通过FNDC5过表达激活p38/MAPK通路时,p-p38 (磷酸化的p38)表达增加,p-p38/p38比值上升,同时促进了成骨相关蛋白如Runx2的表达,表明通路激活对转录因子活性有积极影响。但在某些情况下,p38MAPK通路过度激活可能导致成骨细胞凋亡增加,影响骨形成[40]

JNK通路:在绝经后骨质疏松症里对成骨细胞影响突出。一方面,雌激素水平降低会激活JNK通路,调节细胞周期蛋白D1表达,促使成骨细胞从G1期过渡至S期,维持骨稳态[41];另一方面,该通路能磷酸化激活转录因子c-Jun,协同其他转录因子促进Runx2、骨钙素等成骨细胞特异性基因表达,增强Runx2活性,助力成骨细胞前体细胞成熟分化,推动骨基质合成与矿化。然而,JNK通路过度激活会使成骨细胞内ROS水平攀升,引发氧化应激,激活caspase-3等凋亡蛋白,造成成骨细胞凋亡增加、骨形成能力下滑。此外,JNK通路还参与调节Ⅰ型胶原蛋白、骨桥蛋白等细胞外基质蛋白的合成及碱性磷酸酶的活性,维系骨组织正常架构与功能[42]。不过,JNK通路在成骨细胞中的作用结论并不统一,这受多因素干扰:细胞模型方面,成骨细胞来源不同(如MC3T3-E1与原代细胞),传代次数及培养条件有别,致使细胞对JNK通路激活的响应各异[43];实验方法层面,激活方式多样,检测指标与时间点不同,结果存在差异;体内外环境差别显著,体外环境简化,缺乏细胞间交互及生物力学刺激,体内环境复杂,存在细胞网络及多种调节因素;物种差异同样不可小觑,不同物种成骨细胞基因、蛋白及功能不同,使得JNK通路作用机制与效果在不同物种中有别。

ERK5通路在成骨细胞中的研究相对较少。有研究表明,ERK5通路的激活可促进成骨细胞增殖和存活,抑制成骨细胞凋亡[44]。在成骨细胞分化过程中,ERK5通路可能通过调节NFATc1等因子的活性,促进成骨细胞特异性基因的表达,参与成骨细胞分化和矿化过程[45]。Ma等人[46]的研究为ERK5通路激活的作用提供有力支持。研究发现FSS可激活ERK5,抑制RANKL激活的NFATc1及其下游蛋白表达,进而抑制破骨细胞分化。

4.1.2. 对骨髓间充质干细胞成脂分化的影响

骨髓间充质干细胞(BMSCs)具有多向分化潜能,可分化为成骨细胞、脂肪细胞等[47]。在PMOP患者中,BMSCs向成脂分化增加,向成骨分化减少,导致骨髓脂肪增多,骨量减少。MAPK信号通路在调节BMSCs成脂分化中发挥重要作用[48]。p38MAPK通路的激活可抑制BMSCs成脂分化。当p38MAPK通路被激活时,可抑制过氧化物酶体增殖物激活受体γ (PPARγ)等成脂相关转录因子的表达和活性,减少脂肪细胞特异性基因的表达,如脂肪酸结合蛋白4(FABP4)、脂蛋白脂肪酶(LPL)等,从而抑制BMSCs成脂分化[49]。相反,ERK1/2通路的激活可能促进BMSCs成脂分化。在一些研究中,抑制ERK1/2通路可减少BMSCs成脂分化,增加成骨分化。JNK通路在BMSCs成脂分化中的作用存在争议,一些研究表明JNK通路的激活可促进BMSCs成脂分化,而另一些研究则发现JNK通路的激活对BMSCs成脂分化无明显影响[50]。这可能受到细胞微环境、实验模型差异等因素的干扰,需要更多研究加以明确。

4.2. MAPK信号通路对破骨细胞的作用

4.2.1. 对破骨细胞分化、活化和骨吸收功能的影响

破骨细胞是骨吸收的主要功能细胞,其分化、活化和骨吸收功能的异常增强是PMOP骨量丢失的重要原因。MAPK信号通路在破骨细胞的发育和功能调节中起关键作用[51]。核因子-κB受体活化因子配体(RANKL)是破骨细胞分化和活化的关键调节因子,其通过与破骨细胞前体细胞表面的RANK受体结合,激活多条信号通路,包括MAPK信号通路[52]。RANKL刺激可激活ERK1/2、JNK和p38MAPK通路,促进破骨细胞前体细胞向破骨细胞分化。在破骨细胞活化过程中,ERK1/2通路的激活可增强破骨细胞的骨吸收功能,调节破骨细胞的细胞骨架重组和整合素的表达,促进破骨细胞在骨表面的附着和骨吸收陷窝的形成。JNK通路的激活在破骨细胞活化和骨吸收中也起重要作用,可调节破骨细胞的存活和功能。p38MAPK通路的激活对破骨细胞分化和骨吸收功能也具有重要影响,可促进破骨细胞特异性基因的表达,如组织蛋白酶K(CTSK)、抗酒石酸酸性磷酸酶(TRAP)等,增强破骨细胞的骨吸收能力[53]

4.2.2. 与OPG/RANKL/RANK系统的关系

OPG/RANKL/RANK系统是调节骨重建的重要信号系统。OPG是一种可溶性糖蛋白,可与RANKL结合,竞争性抑制RANKL与RANK的结合,从而抑制破骨细胞的分化、活化和骨吸收功能。MAPK信号通路与OPG/RANKL/RANK系统相互作用,共同调节骨重建平衡[54]。雌激素缺乏可导致OPG表达减少,RANKL表达增加,使RANKL/OPG比值升高,激活破骨细胞分化和骨吸收。研究表明,MAPK信号通路可调节OPG和RANKL的表达。例如,ERK1/2通路的激活可上调成骨细胞OPG的表达,而下调RANKL的表达,从而抑制破骨细胞的分化和骨吸收[55]。相反,p38MAPK通路和JNK通路的激活在某些情况下可促进RANKL的表达,增强破骨细胞的分化和骨吸收功能。此外,RANKL激活的MAPK信号通路也可反馈调节OPG/RANKL/RANK系统的表达,形成复杂的调节网络[56]

4.3. MAPK信号通路在骨重建失衡中的作用机制

在绝经后,由于雌激素水平下降,导致体内多种细胞因子和信号通路的失衡,其中MAPK信号通路的异常激活在PMOP骨重建失衡中起着关键作用。雌激素缺乏可通过多种途径激活MAPK信号通路。一方面,雌激素可直接作用于成骨细胞和破骨细胞表面的雌激素受体,抑制MAPK信号通路的激活。绝经后雌激素水平降低,这种抑制作用减弱,导致MAPK信号通路过度激活[57]。另一方面,雌激素缺乏可引起细胞因子网络失衡,如TNF-α、IL-1、IL-6等促炎细胞因子水平升高。这些细胞因子可通过其相应的受体激活MAPK信号通路,促进破骨细胞分化和骨吸收,抑制成骨细胞功能,导致骨重建失衡[58]。在成骨细胞中,MAPK信号通路的异常激活可影响成骨细胞的增殖、分化和矿化能力,减少骨形成。例如,ERK1/2通路过度激活可能抑制成骨细胞的矿化,p38MAPK通路过度激活可能导致成骨细胞凋亡增加[33]。在破骨细胞中,MAPK信号通路的激活可促进破骨细胞的分化、活化和骨吸收功能,增加骨吸收[51]。同时,MAPK信号通路还可通过调节OPG/RANKL/RANK系统的表达,进一步影响骨重建平衡[54]。此外,MAPK信号通路与其他信号通路之间存在复杂的相互作用,如Wnt/β-catenin信号通路[59]、PI3K/Akt信号通路[60]等,这些信号通路的失衡也参与了PMOP骨重建失衡的发生发展。

5. MAPK信号通路在PMOP治疗中的干预策略现状

当前针对MAPK信号通路在绝经后骨质疏松症(PMOP)治疗中的干预策略主要包括药物干预和物理干预。药物干预方面,部分化学药物可通过抑制或激活特定的MAPK通路分支来调节骨代谢。BMS-582949,是一种临床p38α抑制剂能够阻断p38MAPK通路过度激活,减少破骨细胞分化和骨吸收,在一定程度上增加骨密度[61]。然而,这些化学药物常伴有较多副作用,如影响其他正常细胞的生理功能,导致肝肾功能损伤、胃肠道不适等不良反应,限制了其长期使用和临床推广。

物理干预手段亦是PMOP治疗中的重要方法,如低强度脉冲超声、机械应力刺激等,也被尝试用于调节MAPK信号通路,Xu [62]等人的研究低强度脉冲超声通过大鼠内脏前脂肪细胞中的p38MAPK信号传导抑制增殖并促进细胞凋亡。研究发现亦可能用于促进成骨细胞功能、抑制破骨细胞活性。虽然这些方法具有非侵入性的优点,但作用机制复杂,且不同个体对物理刺激的反应存在差异,难以精准控制治疗效果,治疗效果的稳定性和可重复性有待提高。

6. 现有研究的局限性与多组学技术的应用前景

6.1. 现有研究局限性

目前研究存在多方面局限性。首先,对MAPK信号通路各分支之间以及与其他信号通路相互作用的精细机制尚未完全明确。例如,在复杂的细胞微环境中,不同信号通路之间的交叉对话如何协同调控骨代谢,现有的研究还无法给出全面、准确的解释,这使得干预策略难以做到精准调控[63]。其次,现有的研究大多基于细胞实验和动物模型,在向临床应用转化过程中存在差距。动物模型与人体的生理病理状态存在差异,人体的复杂性使得干预措施的效果和安全性评估更为困难,导致部分在动物实验中有效的干预方法在人体临床试验中效果不佳或出现不良反应[64]

6.2. 多组学技术应用前景

鉴于以上局限性,基于多组学技术的精准治疗成为未来发展方向。多组学技术,如基因组学、转录组学、蛋白质组学和代谢组学等,能够从多个层面全面解析疾病发生发展过程中的分子变化。通过基因组学分析,可以明确个体的基因多态性,筛选出与PMOP易感性和MAPK信号通路异常激活相关的关键基因位点,实现个性化的风险评估和治疗靶点选择[65]。转录组学和蛋白质组学则可以动态监测MAPK信号通路相关基因的表达变化以及蛋白质水平的修饰和调控,帮助深入理解信号通路的激活机制和关键节点[66]。代谢组学能够检测与骨代谢相关的小分子代谢物变化,为评估治疗效果提供更全面的生物标志物[67]

不过,多组学数据整合面临诸多挑战。一方面,不同层面的多组学数据,如基因组学、转录组学、蛋白质组学和代谢组学,它们在数据类型、数据结构、测量尺度等方面均存在差异,具有高度异质性。例如基因组学主要聚焦于DNA序列信息,转录组学反映基因的转录水平,蛋白质组学侧重于蛋白质的表达和修饰,代谢组学着眼于小分子代谢物,要将这些从基因到代谢产物不同层面的数据关联起来,就需要开发复杂的数据整合算法和分析方法,如scmFormer等人工智能模型[68]。另一方面,多组学数据量极其巨大,这对数据存储、计算资源和分析技术都提出了极高的要求。在存储方面,需要高效的存储设备和管理系统来保存海量数据;在计算分析时,需要强大的计算能力来处理复杂的运算,同时还需要优化数据分析流程,以提高分析效率和准确性。目前虽然已经有一些数据整合的方法和工具,但仍无法完全满足实际研究的需求,还需要进一步深入研究和开发更有效的数据整合策略。

基于多组学数据的整合分析,可以构建更加精准的PMOP发病机制模型,为开发特异性针对MAPK信号通路关键靶点的药物提供依据[69]。同时,通过对患者进行多组学特征的精准分型,可以实现个性化治疗方案的制定[70],提高治疗的针对性和有效性,减少不良反应的发生,从而为PMOP的治疗开辟新的途径,推动该领域的临床研究和治疗实践取得重大突破。MAPK信号通路在PMOP骨重建失衡中扮演着关键角色。

7. 亟待解决的关键科学问题

在MAPK通路与PMOP的研究领域,目前仍存在一些亟待解决的关键科学问题。其一,尽管已知MAPK通路各分支对成骨细胞和破骨细胞有重要影响,但各分支之间在不同生理和病理状态下的协同与拮抗关系尚不明确。例如,在PMOP病情发展的不同阶段,ERK、JNK、p38MAPK和ERK5通路之间如何相互作用来调控骨重建,是同步激活、依次激活还是存在相互抑制的关系,这对于深入理解骨重建失衡机制至关重要,也为精准干预提供关键依据。其二,虽然知道MAPK通路与其他信号通路存在相互作用,但这种交叉对话在PMOP发生发展过程中的动态变化规律以及关键调控节点尚未清晰。如MAPK通路与Wnt/β-catenin、PI3K/Akt等信号通路之间在不同疾病进程中,是如何相互影响、共同调控骨代谢相关细胞的功能,明确这些有助于发现新的治疗靶点。其三,在利用多组学技术进行PMOP研究时,如何将多组学数据与MAPK通路的功能研究紧密结合,挖掘出真正与PMOP发病机制和治疗相关的关键信息。例如,如何从海量的基因组学、转录组学数据中筛选出与MAPK通路异常激活密切相关且对PMOP诊断、治疗和预后有指导意义的生物标志物,这将推动基于多组学技术的精准治疗策略的发展。解决这些关键科学问题,将为深入理解MAPK通路在PMOP中的作用机制、开发更有效的治疗方案提供有力支持。

8. 总结

MAPK信号通路在PMOP骨重建失衡中扮演着关键角色。在PMOP中,雌激素缺乏是导致骨重建失衡的重要因素。一方面,雌激素水平下降使得其对MAPK信号通路的抑制作用减弱;另一方面,雌激素缺乏引发细胞因子网络失衡,促炎细胞因子增多,激活MAPK信号通路。该信号通路对成骨细胞和破骨细胞的功能均有显著影响。在成骨细胞中,ERK1/2通路在增殖和早期分化中起重要作用,但过度激活会抑制矿化;p38MAPK通路促进分化和矿化,过度激活则增加细胞凋亡;JNK通路作用复杂,在晚期分化和矿化中有一定作用,过度激活却抑制增殖、分化并促进凋亡;ERK5通路促进增殖和存活,参与分化和矿化过程。同时,MAPK信号通路还调节骨髓间充质干细胞的成脂分化。在破骨细胞中,MAPK信号通路在分化、活化和骨吸收功能中起关键作用,且与OPG/RANKL/RANK系统相互作用,共同调节骨重建平衡。目前,针对MAPK信号通路的干预研究不断发展,但仍面临诸多挑战。深入探究MAPK信号通路在PMOP中的作用机制,有助于开发出更具针对性的治疗策略。未来,结合多组学技术的精准治疗可能成为PMOP治疗的新方向,但在此过程中需要克服多组学数据整合的难题,明确各信号通路间的复杂关系,解决关键科学问题,有望为患者带来更有效的治疗方案,改善患者的生活质量。

NOTES

*第一作者。

#通讯作者。

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