Physiological roles of mitogen-activated-protein-kinase-activated p38-regulated/activated protein kinase

Mitogen-activated protein kinases(MAPKs)are a family of proteins that constitute signaling pathways involved in processes that control gene expression,cell division, cell survival,apoptosis,metabolism,differentiation and motility.The MAPK pathways can be divided into conventional and atypical MAPK pathways.The first group converts a signal into a cellular response through a relay of three consecutive phosphorylation events exerted by MAPK kinase kinases,MAPK kinase,and MAPK.Atypical MAPK pathways are not organized into this three-tiered cascade.MAPK that belongs to both conventional and atypical MAPK pathways can phosphorylate both non-protein kinase substrates and other protein kinases.The latter are referred to as MAPK-activated protein kinases.This review focuses on one such MAPK-activated protein kinase,MAPK-activated protein kinase 5(MK5)or p38-regulated/activated protein kinase(PRAK).This protein is highly conserved throughout the animal kingdom and seems to be the target of both conventional and atypical MAPK pathways.Recent findings on the regulation of the activity and subcellular localization,bona fide interaction partners and physiological roles of MK5/PRAK are discussed.

p38 mitogen-activated protein kinase regulates type-Ⅰ vs type-Ⅱ phenotyping of human vascular endothelial cells

AIM: To identify kinases involved in phenotype regulation of vascular endothelial cells(VECs): Proproliferative G-protein signaling 5(RGS5)^(high)(typeⅠ) vs anti-proliferative RGS5^(low)(typeⅡ) VECs.METHODS: Proteomic kinase assays were performed to identify the crucial kinase involved in the phenotype regulation of human VECs using typeⅠ VECs, which promotes the proliferation of human vascular smooth muscle cells(VSMCs), and typeⅡ VECs, which suppress the proliferation of human VSMCs. The assays were performed using multiple pairs of typeⅠ and typeⅡ VECs to obtain the least number of candidates. The involvement of the candidate kinases was verified by evaluating the effects of their specific inhibitors on the phenotype regulation of human VECs as well as the expression levels of regulator of RGS5, which is the causative gene for the "typeⅡ to typeⅠ" phenotype conversion of human VECs. RESULTS: p38α mitogen-activated protein kinase(p38α MAPK) was the only kinase that showed distinctive activities between typeⅠ and typeⅡ VECs: p38α MAPK activities were low and high in type-Ⅰand typeⅡ VECs, respectively. We found that an enforced expression of RGS5 indeed lowered p38α MAPK activitiesin typeⅡ VECs. Furthermore, treatments with a p38α MAPK inhibitor nullified the anti-proliferative potential in typeⅡ VECs. Interestingly, MAPK inhibitor treatments enhanced the induction of RGS5 gene. Thus, there is a vicious cycle between "RGS5 induction" and "p38α MAPK inhibition", which can explain the unidirectional process in the stress-induced "typeⅡ to typeⅠ" conversions of human VECs. To understand the upstream signaling of RGS5, which is known as an inhibitory molecule against the G protein-coupled receptor(GPCR)-mediated signaling, we examined the effects of RGS5 overexpression on the signaling events from sphingosine-1-phosphate(S1P) to N-cadherin, because S1 P receptors belong to the GPCR family gene and N-cadherin, one of their downstream effectors, is reportedly involved in the regulation of VEC-VSMC interactions. We found that RGS5 specifically bound with S1P1. Moreover, N-cadherin localization at intercellular junctions in typeⅡ VECs was abolished by "RGS5 overexpression" and "p38α MAPK inhibition".CONCLUSION: p38α MAPK plays crucial roles in "type-Ⅰ vs type-Ⅱ" phenotype regulations of human VECs at the downstream of RGS5.

Saponins from Panax japonicus attenuate age-related neuroinflammation via regulation of the mitogen-activated protein kinase and nuclear factor kappa B signaling pathways

Neuroinflammation is recognized as an important pathogenic factor for aging and related cognitive disorders. Mitogen-activated protein kinase and nuclear factor kappa B signaling pathways may mediate neuroinflammation. Saponins from Panax japonicus are the most abundant and bioactive members in rhizomes of Panax japonicus, and show anti-inflammatory activity. However, it is not known whether saponin from Panax japonicus has an anti-inflammatory effect in the aging brain, and likewise its underlying mechanisms. Sprague-Dawley rats were divided into control groups(3-, 9-, 15-, and 24-month-old groups) and saponins from Panax japonicus-treated groups. Saponins from Panax japonicus-treated groups were orally administrated saponins from Panax japonicus at three doses of 10, 30, and 60 mg/kg once daily for 6 months until the rats were 24 months old. Immunohistochemical staining and western blot assay results demonstrated that many microglia were activated in 24-month-old rats compared with 3-and 9-month-old rats. Expression of interleukin-1β, tumor necrosis factor-α, cyclooxygenase-2, and inducible nitric oxide synthase increased. Each dose of saponins from Panax japonicus visibly suppressed microglial activation in the aging rat brain, and inhibited expression levels of the above factors. Each dose of saponins from Panax japonicus markedly diminished levels of nuclear factor kappa B, IκBα, extracellular signal-regulated kinase, c-Jun N-terminal kinase, and p38. These results confirm that saponins from Panax japonicus can mitigate neuroinflammation in the aging rat brain by inhibition of the mitogen-activated protein kinase and nuclear factor kappa B signaling pathways.

Neuroprotective mechanisms of rutin for spinal cord injury through anti-oxidation and anti-inflammation and inhibition of p38 mitogen activated protein kinase pathway

Rutin has anti-inflammatory, antioxidant, anti-viral, anti-tumor and immune regulatory effects. However, the neuroprotective effects of rutin in spinal cord injury are unknown. The p38 mitogen activated protein kinase(p38 MAPK) pathway is the most important member of the MAPK family that controls inflammation. We assumed that the mechanism of rutin in the repair of spinal cord injury is associated with the inhibition of p38 MAPK pathway. Allen's method was used to establish a rat model of spinal cord injury. The rat model was intraperitoneally injected with rutin(30 mg/kg) for 3 days. After treatment with rutin, Basso, Beattie and Bresnahan locomotor function scores increased. Water content, tumor necrosis factor alpha, interleukin 1 beta, and interleukin 6 levels, p38 MAPK protein expression and caspase-3 and-9 activities in T8–9 spinal cord decreased. Oxidative stress related markers superoxide dismutase and glutathione peroxidase levels increased in peripheral blood. Rutin exerts neuroprotective effect through anti-oxidation, anti-inflammation, anti-apoptosis and inhibition of p38 MAPK pathway.

胎儿和出生后机体皮肤内p38MAPK及MAPKKs基因表达变化的比较性研究

目的 探讨p38丝裂素活化蛋白激酶(p38mitogen- activated protein kinase,p38MAPK)及其上游信号分子MAPKKs(mkk3和mkk6 )基因,在不同胎龄胎儿皮肤和出生后机体皮肤组织中表达的变化,及其可能的生物学意义。 方法 用病理学技术检测不同发育时期皮肤的结构特征后,提取18例不同胎龄(13～32周)的胎儿皮肤和6例出生后机体皮肤组织(作为对照)的总RNA,分离m RNA,用逆转录-聚合酶链反应(reverse transcription- polymerasechain reaction,RT- PCR)方法检测3种基因在不同组织中的表达规律。 结果 p38MAPK,m kk3和mkk6基因在不同发育阶段的皮肤组织中都有表达。在早期妊娠胎儿的皮肤组织中,这三种基因表达较强,随着胎儿的生长发育,皮肤组织内这三种基因表达逐渐减弱。在出生后机体的皮肤细胞中,p38MAPK、mkk3和mkk6基因的表达量分别为妊娠早期皮肤的39.6 %、6 3.5 %和5 4 .5 % ,明显减弱(P<0 .0 1)。 结论 p38MAPK、mkk3和mkk6基因在不同发育阶段人皮肤组织内都有表达,显示细胞外信号引起的p38MAPK信号通路可能对皮肤的发生、结构功能的维持以及伤后修复十分重要。在早期妊娠胎儿皮肤中p38MAPK及其上游信号分子MAPKKs基因的高表达可能是胎儿皮肤组织细胞快速增殖、皮肤创面无瘢痕愈合的机制之一。

P38MAPK在慢性阻塞性肺疾病中的作用

慢性阻塞性肺疾病是一种慢性气道炎症性疾病,是肺部对有害颗粒或气体的所产生的异常炎症反应,这种气道炎症常导致持续性的气流受限和肺功能的进行性下降。此外,由肺内炎症反应等所导致的氧化应激反应也参与了COPD的发病。p38丝裂原活化蛋白激酶（p38 mitogen-activated protein kinase,p38MAPK）是细胞内重要的信号传递者,

补肾活血方对兔NPMSCs移植治疗退变椎间盘P 38 MAPK信号通路的影响

目的探讨补肾活血方对兔髓核间充质干细胞(nucleus pulposus-derived mesenchymal stem cells,NPMSCs)移植治疗退变椎间盘P 38丝裂原活化蛋白激酶(p38 mitogen-activated protein kinase,P 38 MAPK)信号通路的影响。方法选取128只SPF级健康新西兰大白兔,其中2例用于NPMSCs的获取、纯化及培养,选取24只为假手术组(A组);兔退变椎间盘模型成功100只,模型组(B组,24只)、补肾活血方组(C组,24只)、NPMSCs移植组(D组,24只)、补肾活血方+NPMSCs移植组(E组,24只),死亡6只。每组在治疗前、治疗后1周、治疗后2周、治疗后3周4个时间点均处死6只兔,取相应椎间盘,采用酶联免疫测定每组大兔不同时间点椎间盘P 38 MAPK、基质金属蛋白酶3(matrix metalloproteinase 3,MMP-3)、基质金属蛋白酶7(matrix metalloproteinase 7,MMP-7)的表达。结果(1)各组变化趋势:A组、B组组内不同时间点P 38 MAPK、MMP-3、MMP-7蛋白相对表达差异无统计学意义(P>0.05);C组、D组、E组P 38 MAPK、MMP-3、MMP-7蛋白相对表达与治疗前、治疗后1周、治疗后2周、治疗后3周呈下降趋势,各组组内差异有统计学意义(P<0.01)。(2)与A组比较:B组、C组、D组、E组P38MAPK、MMP-3、MMP-7蛋白相对表达在治疗前、治疗后1周、治疗后2周、治疗后3周均升高,组间差异有统计学意义(P<0.01)。(3)与B组比较:C组、D组、E组P 38 MAPK、MMP-3、MMP-7蛋白相对表达在治疗前差异无统计学意义(P>0.05);在治疗后1周、治疗后2周、治疗后3周均降低,组间差异有统计学意义(P<0.01)。(4)与C组比较:D组P 38 MAPK、MMP-3、MMP-7蛋白相对表达在治疗前、治疗后1周、治疗后2周、治疗后3周时同期差异无统计学意义(P>0.05);E组P 38 MAPK、MMP-3、MMP-7蛋白相对表达在治疗后1周、治疗后2周、治疗后3周均降低,组间差异有统计学意义(P<0.01)。(5)与D组比较:E组P 38 MAPK、MMP-3、MMP-7蛋白相对表达在治疗后1周、治疗后2周、治疗后3周均降低,组间差异有统计学意义(P<0.01)。结论补肾活血方对兔NPMSCs移植治疗退变椎间盘具有协同作用;其机制可能与抑制P 38 MAPK信号通路,下调MMP-3、MMP-7蛋白相关。

锰诱导PC12细胞凋亡与p-38MAPKs的关系

目的 以鼠嗜铬神经瘤细胞 (PC12 )为模型 ,筛选锰对神经细胞增殖抑制作用的时间及剂量 ,观察细胞形态学、细胞周期和生化指标改变与丝裂原活化蛋白激酶 (p38MAPKs)活化表达间的关系。方法 用 2 0 0 ,4 0 0 ,6 0 0 ,80 0μmol/LMnCl2 的培养液 ,分别作用对数生长期PC12细胞 1,2 ,3,4d后 ,用噻唑蓝比色 (MTT)筛选锰的细胞毒性剂量 ;流式细胞仪检测细胞周期分布 ;透射电镜观察细胞形态学变化 ;琼脂糖凝胶电泳检测MnCl2 对PC12细胞基因组DNA的影响。蛋白印迹 (western -blot)法检测 p -p38。结果 MTT实验结果显示 ,2 0 0～ 80 0 μmol/LMnCl2 作用 1,2 ,3,4d对PC12有显著的抑制作用 ,呈剂量和时间依赖趋势 ,6 0 0 μmol/LMnCl2 作用 4d对PC12的抑制率可达 5 0 %以上。流式细胞仪检测实验表明 :6 0 0 μmol/LMnCl2 作用 4d将PC12细胞周期阻滞在S期 ,诱导细胞凋亡 ,与电镜结果一致 ,同样条件下细胞DNA碎片化。Western -blot实验显示 6 0 0 μmol/LMnCl2 作用 1,2 ,3,4dp -p38逐渐升高 ,3d时较对照组增加 6 6倍 (n =3,P <0 0 5 ) ,2 0 0 ,4 0 0 ,6 0 0 μmol/LMnCl2 作用 4d时 ,磷酸化蛋白 38(p - p38)也逐渐升高 ,4 0 0 μmol/LMnCl2 作用 4d时较对照组升高 4 7倍 (n =3,P <0 0 5 )。结论 锰通过MEK3/

特异性p^(38)MAPK抑制剂SB203580对乳鼠小脑颗粒神经元的保护作用

目的 研究 p38丝裂原激活蛋白激酶 (MAPK)选择性抑制剂SB2 0 35 80对乳鼠小脑颗粒神经元凋亡的保护作用。方法 SD乳鼠小脑颗粒神经元培养 ,琼脂糖凝胶电泳 ,SAPK/JNK分析试剂盒作激酶分析。结果 PI 3 K的特异性抑制剂LY2 940 0 2诱导小脑颗粒神经元凋亡 ,但SB2 0 35 80通过抑制细胞凋亡而促进小脑颗粒神经元的存活 ,且有浓度依赖性。LY2 940 0 2诱导凋亡的颗粒神经元中c Jun的表达量和磷酸化水平均升高 ,JNK被激活。但是 ,当小脑颗粒神经元生长在含SB2 0 35 80的高钾培养基中 ,c Jun的表达量、磷酸化水平和JNK的活性都明显的降低。结论 SB2 0 35 80通过抑制JNK的活性 ,降低c Jun的表达和磷酸化水平 。

黄芪对脂多糖诱导大鼠急性肺损伤p38 MAPK表达的影响

目的探讨脂多糖(LPS)诱导急性肺损伤(ALI)大鼠肺组织磷酸化p38 MAPK表达的变化以及黄芪对其之影响。方法静脉注射LPS复制大鼠ALI模型。随机分成3组:正常对照组、ALI组和黄芪组。采用蛋白质印迹检测肺组织磷酸化p38 MAPK的表达,并观察大鼠动脉血氧分压(PaO2)、肺湿/干重比(W/D)、支气管肺泡灌洗液(BALF)白蛋白、血清TNF-α的变化以及肺组织病理学改变。结果LPS诱导大鼠ALI时肺组织磷酸化p38 MAPK的表达较正常对照组显著增加(P<0.01)。黄芪注射液可显著抑制大鼠肺组织磷酸化p38MAPK表达,降低W/D、BALF白蛋白以及血清TNF-α含量,使下降的PaO2回升,减轻肺组织病理学损伤。结论ALI时肺组织p38 MAPK磷酸化表达增加;黄芪注射液对内毒素性肺损伤有保护作用,其机制可能与抑制磷酸化p38 MAPK的表达有关。

p38α MAPK pathway:A key factor in colorectal cancer therapy and chemoresistance

Colorectal cancer(CRC)remains one of the most common malignancies in the world.Although surgical resection combined with adjuvant therapy is effective at the early stages of the disease,resistance to conventional therapies is frequently observed in advanced stages,where treatments become ineffective.Resistance to cisplatin,irinotecan and 5-fluorouracil chemotherapy has been shown to involve mitogen-activated protein kinase(MAPK)signaling and recent studies identified p38αMAPK as a mediator of resistance to various agents in CRC patients.Studies published in the last decade showed a dual role for the p38αpathway in mammals.Its role as a negative regulator of proliferation has been reported in both normal(including cardiomyocytes,hepatocytes,fibroblasts,hematopoietic and lung cells)and cancer cells(colon,prostate,breast,lung tumor cells).This function is mediated by the negative regulation of cell cycle progression and the transduction of some apoptotic stimuli.However,despite its anti-proliferative and tumor suppressor activity in some tissues,the p38αpathway may also acquire an oncogenic role involving cancer related-processes such as cell metabolism,invasion,inflammation and angiogenesis.In this review,we summarize current knowledge about the predominant role of the p38αMAPK pathway in CRC development and chemoresistance.In our view,this might help establish the therapeutic potential of the targeted manipulation of this pathway in clinical settings.

丝裂原活化蛋白激酶p38信号传导机制在高温致畸中的作用

高温是常见的致畸因素之一．对多种哺乳动物包括人类具有致畸作用，但高温致畸机制尚不明确。最近研究发现，高温作为外源性刺激会使胚胎发育的敏感期生物体细胞凋亡发生紊乱，引起胚胎发育异常，导致先天畸形的发生。其凋亡作用机制涉及丝裂原活化蛋白激酶（mitagen-activated protein kinases，MAPKs）凋亡信号通路中的丝裂原活化蛋白激酶p38（p38MAPK）．p38MAPK信号传导通路在高温致畸中发挥重要作用，成为高温致畸机制研究的新领域。

IL-12、LPS对肾小管上皮细胞中lck/P_(38)信号传递的影响

【目的】探讨IL 12、LPS对肾小管上皮细胞中lck基因表达及活性改变的影响 ,明确lck/P3 8信号传递途径在炎症过程的作用。【方法】用原位杂交、放射自显影分别检测lck基因表达及lck活性 ,用免疫印迹法对肾小管上皮细胞在IL 12、LPS刺激下其P3 8磷酸化进行测定。【结果】肾小管上皮细胞经IL 12 ,LPS刺激后lckmRNA表达水平增高 ,lck活性在刺激后 5min时最强 ,加入lck抑制剂PP1,IL 12刺激lck活性明显减弱。IL 12及LPS可以促进肾小管上皮细胞中P3 8活化、磷酸化 ,在 15min时最强 ,加入lck抑制剂后则抑制IL 12刺激时的P3 8磷酸化 ,而LPS刺激组不明显。【结论】IL 12 ,LPS可通过促进肾小管上皮细胞中lck/P3 8活化 ,参与炎症过程。

Role of the IL-33/ST2/p38 signaling pathway in the immune response of corneal epithelial cells to Aspergillus fumigatus infection

AIM: To investigate the expression of interleukin(IL)-33 in the cornea and human corneal epithelial cells(HCECs) exposed to Aspergillus fumigatus(A. fumigatus), and to determine the function of IL-33/ST2/p38 signaling pathway in the immune response of corneal epithelial cells to A. fumigatus infection.METHODS: The mRNA and protein expression of IL-33 in HCECs and mice corneas were examined by quantitative real-time reverse transcription polymerase chain reaction(q RT-PCR) and Western blot analysis, respectively. IL-33 expression was also detected in cornea samples from healthy donors and patients with fungal keratitis with immunohistochemistry. The cultured HCECs were treated with inactive A. fumigatus hyphae at various concentrations with or without recombinant human IL-33 protein, soluble recombinant ST2 protein, specific ST2 neutralizing antibody, or the mitogen-activated protein kinase(MAPK) p38 inhibitor SB203580 for evaluation of the expression and activation of IL-33/ST2/p38 signaling in the regulation of proinflammatory cytokines. The production levels of IL-6 and IL-1β were determined by qR T-PCR and enzymelinked immunosorbent assay(ELISA). The proliferation of HCECs was determined by a Cell Counting Kit-8(CCK8) assay and cell count.RESULTS: IL-33 expression levels increased in the corneal tissues of patients with fungal keratitis and in mice corneas of experimental A. fumigatus infection,as well as in HCECs with infection of A. fumigatus. A. fumigatus strongly stimulated HCECs-generated proinflammatory cytokine(IL-6 and IL-1β) production at both the mRNA and protein levels. This production of proinflammatory mediators stimulated by A. fumigatus was further stimulated by IL-33 and was prevented by soluble ST2 protein or ST2 neutralizing antibody. Moreover, IL-33 naturally promoted the p38 phosphorylation induced by A. fumigatus, which was suppressed by soluble ST2 protein. The MAPK p38 inhibitor SB203580 also inhibited the A. fumigatus-induced proinflammatory cytokine production. IL-33 administration for 48 h and 72 h promoted the proliferation of HCECs, which was attenuated by treatment with soluble recombinant human ST2 protein.CONCLUSION: A. fumigatus elevates IL-33 expression in human and mice corneas and HCECs. Thus, IL-33/ST2/p38 signaling may play an important role in amplifying the immune response of corneal epithelial cells to A. fumigatus infection. Besides, IL-33 promotes the cell proliferation of HCECs via its receptor ST2. These findings suggest a novel autocrine mechanism of amplification of the fungalinduced inflammatory response in the corneal epithelium, highlighting a potential therapeutic target for fungal keratitis.

A new cell death program regulated by toll-like receptor 9 through p38 mitogen-activated protein kinase signaling pathway in a neonatal rat model with sepsis associated encephalopathy

Background:Sepsis,a serious condition with high mortality,usually causes sepsis associated encephalopathy(SAE)that involves neuronal cell death.However,the cell death programs involved and their underlying mechanisms are not clear.This study aimed to explore the regulatory mechanisms of different cell death programs in SAE.Methods:A neonatal rat model of SAE was established by cecal ligation and perforation.Survival rate and vital signs(mean arterial pressure and heart rate)were monitored,nerve reflexes were evaluated,and cortical pathological changes were observed by hematoxylin and eosin staining.The expression of pyroptosis,apoptosis,and necroptosis(PANoptosis)-related proteins,mitogen-activated protein kinase(MAPK),and its upstream regulator toll-like receptor 9(TLR9)were detected.The expression of TLR9 in neurons was observed by immunofluorescence staining.The ultrastructure of neurons was observed by transmission electron microscope.Results:First,PANoptosis was found in cortical nerve cells of the SAE rats.Meanwhile,the subunits of MAPKs,p38 MAPK,Jun N-terminal kinase,and extracellular signal-regulated kinase(ERK)were activated.After pharmacologically inhibiting each of the subunits,only p38 MAPK was found to be associated with PANoptosis.Furthermore,blocking the p38 MAPK signaling pathway activated necroptosis but inhibited apoptosis and pyroptosis.When necroptosis was pharmacologically inhibited,apoptosis and pyroptosis were reactivated.Finally,we found that the expression of TLR9,a regulator of MAPKs,was significantly increased in this model.After down-regulation of TLR9,p38 MAPK,and ERK signaling pathways were inhibited,which led to the inhibition of PANoptosis.Further analysis found that down-regulation of TLR9 improved the survival rate and reduced the pathological changes in SAE rats.Conclusions:Our study showed that the programs comprising PANoptosis are activated simultaneously in SAE rats.TLR9 activated PANoptosis through the p38 MAPK signaling pathway.TLR9 may work as a potential target for SAE treatment.

Efficacy of needling acupoints of Guanyuan(CV4), Sanyinjiao(SP6), Zusanli(ST36), Pishu(BL20), Shenshu(BL23), Zigong(EX-CA1) on expression of p38 mitogen-activated protein kinase in ovarian tissue in rats with premature ovarian failure induced by cyclophosp

OBJECTIVE:To investigate the efficacy of needling acupoins of Guanyuan(CV4),Sanyinjiao(SP6),Zusanli(ST36),Pishu(BL20),Shenshu(BL23),Zigong(EX-CA1)on the expression of p38 mitogen-activated protein kinase(p38MAPK)in ovarian tissue in rats with premature ovarian failure induced by cyclophosphamide,and to study the underlying mechanism.METHODS:Forty specific pathogen free female Sprague-Dawley rats were randomly divided into the blank group,the model group,the acupuncture group,the Western Medicine group and the Western Medicine combined with acupuncture group.Except the blank group,the rest of the rats were given with cyclophosphamide for 14 d to establish premature ovarian failure model.No intervention was conducted in the blank group and model group;the acupuncture group was given with acupuncture daily;the Western Medicine group was given with estradiol valerate(0.09 mg/kg)by intragastrical gavage daily;the combination group was given with acupuncture combined with estradiol valerate(0.09 mg/kg)daily.Each group was intervened in continuously for 14 d.After the last treatment,the levels of estradiol(E2),follicle stimulating hormone(FSH)and luteinizing hormone(LH)were detected by enzyme-linked immunosorbent assay,then the ovarian tissue was dissected.Western blot was used to detect the expression of p38 MAPK protein.RESULTS:Compared with the blank group,E2 in the serum of rats in the model group was significantly decreased(P<0.05),FSH and LH were significantly increased(P<0.05),and the expression of p38 MAPK protein in the ovarian tissue of the rats was significantly increased(P<0.05).Compared with the model group,E2 in the serum of the acupuncture group,Western Medicine group and the combination group were significantly increased(P<0.05),FSH and LH levels were significantly decreased(P<0.05),and the expression of p38MAPK protein in the ovarian tissue of the rats was significantly decreased(P<0.05).However,there was no statistically significant difference between the Western Medicine group and the acupuncture group(P>0.05).CONCLUSIONS:Acupuncture has the same effect as estrogen in interfering POF caused by cyclophosphamide,and its mechanism may be related to inhibiting the expression of p38MAPK protein in ovarian tissue and affecting the activation of p38MAPK signaling pathway.

Xiaokeping-containing serum suppresses high-glucose-induced proliferation of mesangial cells involved in the regulation of cell cycle progression and the p38 mitogen-activated protein kinase pathway

OBJECTIVE: To investigate the efficacy of Xiaokeping(XKP)-containing serum on the proliferation of high-glucose-induced mesangial cells(MCs)and the potential underlying mechanism.METHODS: XKP-containing serum was prepared by the intragastric administration of XKP in rats.HBZY-1 cells were cultured with normal glucose(NC group), high glucose(HG group), and high glucose with different XKP concentrations. Cell proliferation was assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay,and the cell cycle distribution was detected by flow cytometry. The expression of p38 mitogen-activated protein kinase(p38 MAPK) pathway components in MCs was detected by Western blotting and quantitative real-time polymerase chain reaction.RESULTS: The MC proliferation level in the high-glucose group was significantly higher than that in the normal control group, and XKP suppressed the HG-induced proliferation of MCs dose dependently. Moreover, flow cytometry revealed that XKP blocked cell cycle progression by inducing cell cycle arrest in G1 phase and inhibiting S phase entry. XKP down-regulated the protein and m RNA expression of p38 MAPK in MCs(P < 0.05 vs HG).CONCLUSION: The present study demonstrated that XKP-containing serum inhibits high-glucoseinduced proliferation of MCs by causing cell cycle arrest at G1 phase and inhibiting S phase entry. The underlying mechanism involves the down-regulation of the p38 MAPK signaling pathway, providing a theoretical basis for the use of XKP to treat diabetic kidney disease.

Involvement of p38 mitogen-activated protein kinase in the regulation of platelet-derived growth factor -induced cell migration

The aim of this study was to investigate the role of p38 mitogen-activated protein kinase(MAPK)in cell migration induced by platelet-derived growth factor(PDGF).Western blot was performed to detect the phosphorylation of p38 in NIH3T3 cells treated with PDGF.A Transwell cell migration system was used to determine the effects of PDGF treatment on the migration of NIH3T3 cells and the influence of p38 deficiency on this process in a p38 gene knockout(p38^(−/−))mouse embryonic fibroblast cell line.On the stimulation of PDGF,the migration of NIH3T3 cells was significantly increased(P<0.001)compared to the control and p38 MAP kinase was simultaneously phosphorylated.Furthermore,the PDGF-induced cell migration was significantly blocked in p38 gene knockout(p38^(−/−))mouse embryonic fibroblasts(MEFs)(P<0.001)as compared with the wild type cells(p38+/+).p38 MAPK plays an important role in the regulation of cell migration induced by PDGF.