Estrogen and TMJ Pain

雌激素和颞下颌关节疼痛

• 批准号: 8773730
• 负责人: PHILLIP R KRAMER
• 金额: $ 8.7万
• 依托单位: TEXAS A&M UNIVERSITY HEALTH SCIENCE CTR
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-15 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8773730
• 关键词: Acute; Address; Adrenergic Receptor; Affect; Animals; Arthralgia; Axon; Binding; Binding Sites; Biological Assay; Cells; Cervical; Chemicals; Chronic; Clinical Trials; Collaborations; DNA; Diestrus; Electrophoretic Mobility Shift Assay; Estradiol; Estrogen Receptors; Estrogens; Estrous Cycle; Feeding behaviors; Female; Filament; Future; GABA-A Receptor; Gene Expression; Genes; Glycine; Glycine Receptors; Goals; Gonadal Hormones; Hypersensitivity; Individual; Injection of therapeutic agent; Ligation; Ligature; Luciferases; Masseter Muscle; Measures; Mediating; Menstruation; Methodology; Modeling; Neuroglia; Neurons; Nociception; Orofacial Pain; Pain; Patients; Peripheral; Phase; Physiological; Proestrus; Rattus; Reporter; Reporting; Role; Secure; Signal Transduction; Simplexvirus; Simulate; Site; Small Interfering RNA; Staging; Staining method; Stains; Structure of trigeminal ganglion; Sympathomimetic Amines; Symptoms; Temporomandibular Joint; Temporomandibular joint disorder pain; Tendon structure; Testosterone; Tissues; Trigeminal subnucleus caudalis; United States; Woman; base; beta-2 Adrenergic Receptors; chromatin immunoprecipitation; extracellular; gamma-Aminobutyric Acid; ganglion cell; knock-down; male; nociceptive response; novel; orofacial; receptor; response; transcription factor

DESCRIPTION (provided by applicant): Women report greater temporomandibular joint (TMJ) pain when the concentration of estrogen is diminishing. Consistent with these results, estrogen reduces TMJ hypersensitivity in proestrus rats, when estrogen concentrations are highest. In our lab, a large gene array study (>10,000 genes) indicated that gene expression in the rat trigeminal ganglia (TG) was significantly affected by increased estrogen. High proestrus versus low diestrus levels of 17ß-estradiol resulted in a 16 to 34 fold increase in the GABAA receptor subunit α6 (Gabrα6), the glycine receptor subunit α2 (Glrα2) and the beta-adrenergic receptor subunit ß1 (Adrß1). This significant increase occurred in the TG of naïve rats and in rats with ligature of the masseter tendon, a model of chronic (>6 months) myogenic TMJ hypersensitivity. Since GABA, glycine and sympathomimetic amines can inhibit hypersensitivity the knock-down of Gabrα6, Glrα2 and Adrß1 expression would be expected to increase hypersensitivity. In preliminary studies siRNA knock-down of Gabrα6 expression in the TG increased hypersensitivity, increased the level of phosphorylated-ERK (p-ERK) in TG neurons and increased neuronal electrical activity. A homology search for estrogen receptor α and ß (ER α and ERß) binding sites 10kb of the transcriptional start site for these three genes showed that at least one potential binding site was present but the mechanism regulating the estrogen response of these genes is unknown. Based on this information we hypothesize that 17 ß-estradiol decreased TMJ hypersensitivity at proestrus by increasing Gabrα6, Glrα2 and Adrß1 expression in the TG and that this estrogen effect was due to interaction with the estrogen receptor and sequence proximal of the transcriptional start site. To address this hypothesis we propose two specific aims, in Aim #1 we will determine in the TG the role of Gabrα6, Glrα2 and Adrß1 in modulating TMJ hypersensitivity/cellular activity in both males and females. To complete aim #1 a ligature will be placed on the masseter tendon and TG expression of Gabrα6, Glrα2, and Adrß1 will be reduced through antagonists or siRNA. Hypersensitivity/cellular activity will be assessed at an acute stage (7 days post-ligature) and at a chronic stage (6 months post-ligature) using von Frey filaments, meal duration, electrophysiological recordings and by quantitating p-ERK levels. The goal of Aim #2 will be to characterize the role of ERα and ERß in controlling Gabrα6, Glrα2, and Adrß1 expression using chromatin immunoprecipitation, electrophoretic mobility shift assays and luciferase reporter constructs. We expect to show that an altered expression of these three genes can affect the TMJ nociceptive response and that these genes are responsible, in part, for the decrease in hypersensitivity observed in proestrus rats. We also expect to determine the mechanism by which estrogen modulates expression of these genes in TG cells.

描述（由适用提供）：雌激素浓度减少时，妇女报告了更大的颞下颌关节（TMJ）疼痛。与这些结果一致，当雌激素浓度高度重视时，雌激素会降低前肌大鼠的TMJ超敏反应。在我们的实验室中，一项大型基因阵列研究（> 10,000个基因）表明，大鼠三叉神经节（TG）中的基因表达受到雌激素增加的显着影响。高弹性与低卵子水平的高度 17ß-雌二醇导致GABAA受体亚基α6（GABRα6），甘氨酸受体亚基α2（GLRRRα2）和β-肾上腺素受体亚基亚基1（ADRß1）增加16至34倍。这种显着增加发生在幼稚大鼠的TG和肌腱绑扎的大鼠中，这是一种慢性（6个月）肌源性TMJ超敏反应的模型。由于GABA，甘氨酸和交感神经胺可以抑制超敏反应，因此预计GABRα6，GLRα2和ADRß1表达的敲低会增加超敏反应。在初步研究中，在TG中，GABRα6表达的siRNA敲低增加了超敏反应，增加了TG神经元中磷酸化 - ERK（P-ERK）的水平，并增加了神经元电活动。对这三个基因的转录起始位点的雌激素受体α和ß（ERα和ERß）结合位点的同源搜索表明，至少存在一个潜在的结合位点，但是计算这些基因雌激素反应的机制尚不清楚。基于此信息，我们假设17β-雌二醇通过增加TG中的GABRα6，GLRα2和ADRß1表达来改善pro的TMJ超敏反应，并且这种雌激素效应是由于与雌激素受体的相互作用而引起的，并且转录起始位点的接近近端。为了解决这一假设，我们提出了两个具体目标，在目标＃1中，我们将在TG中确定GABRα6，GLRα2和ADRß1在调节男性和女性中TMJ超敏反应/细胞活性中的作用。为了完成目标＃1，将通过拮抗剂或siRNA降低GABRα6，GLRα2和ADRß1的肌肌腱和TG表达。高敏性/细胞活性将在急性阶段（7天）后（7天）和慢性阶段（结膜后6个月）进行评估，使用弗雷丝，进餐时间，电生理记录和定量P-ERK水平。 AIM＃2的目标是表征ERα和ERß使用染色质免疫沉淀，电泳迁移率转移测定法和荧光素酶报道构建体来控制GABRα6，GLRα2和ADRß1表达的作用。我们期望表明，这三个基因的表达改变会影响TMJ伤害性反应，并且这些基因部分原因是在促进大鼠中观察到的高敏性降低。我们还期望确定雌激素调节这些基因在TG细胞中的表达的机制。