Inflamation-Gene Expression by Monocytes in Frailty

描述（由申请人提供）：与非体弱的老年人相比，体弱的老年人在功能下降、跌倒、住院、养老院安置和早期死亡方面的风险更高。新出现的证据表明，以CRP和IL-6水平升高为标志的炎症与身体虚弱有关。然而，对于虚弱的老年人炎症系统激活的范围和潜在机制知之甚少。单核细胞在局部和全身炎症的激活和调节中起着关键作用，研究编码细胞因子介质和受体的基因的单核细胞表达可以为了解脆弱时炎症系统激活的分子机制提供相当大的见解。这项提议的短期目标是建立从虚弱的老年人分离的单核细胞炎症特异性基因表达的特异性调节的初步数据。该项目的长期目标是利用这些发现进行更深入的病因学和干预性研究。我们假设虚弱的老年人在组成性和脂多糖诱导的单核细胞编码IL-6、tnf - α、IL-1 β和IL-1受体拮抗剂（IL-1ra）的基因表达上有显著的改变。本提案的主要目标是验证这一假设，并进一步探索脆弱综合征中组成型和lps诱导的单核细胞表达基因编码80种其他细胞因子介质和细胞表面分子的初步证据。为了实现这些目标，我们提出了一项探索性研究（R21），研究社区居住的体弱和非体弱老年人中84种细胞因子介质和细胞表面分子编码基因的组成性和lps诱导的单核细胞表达。一个经过验证的虚弱筛查工具将被用于识别15对年龄、种族和性别匹配的虚弱和非虚弱的老年人。单核细胞将在存在和不存在LPS的情况下分离和培养。使用市售的含有IL-6、tnf - α、il -1 β、IL-1ra和其他80种细胞因子介质和细胞表面分子的cdna的炎症特异性基因阵列，将评估和比较体弱和非体弱受试者的组成型和lps诱导的单核细胞基因表达。有显著差异的候选基因将进一步通过定量RT-PCR进行评估。这项初步评估的组成和lps诱导单核细胞表达的基因编码IL-6， tnf - α, il -1 β, IL-1ra，将为更明确的单核细胞产生和调节这些重要的细胞因子介质的机制研究奠定基础虚弱的老年人。该项目还将探索体弱多病的老年人体内编码80种其他细胞因子介质和细胞表面分子的基因的组成和lps诱导的单核细胞表达调节的初步证据。因此，它将作为一个假设生成项目和假设完善的基础，这将为未来的机制和潜在的老年虚弱的干预性研究开辟新的途径。

DESCRIPTION(provided by applicant): Frail older adults are at increased risk for functional decline, falls, hospitalization, nursing home placement, and early mortality as compared to non-frail older adults. Emerging evidence suggests that inflammation, as marked by elevated levels of CRP and IL-6, is associated with frailty. However, little is known about the scope of, and the underlying mechanisms that contribute to, the activation of the inflammation system in frail older adults. Monocytes play pivotal roles in the activation and regulation of local and systemic inflammation, and investigating monocytic expression of genes encoding cytokine mediators and receptors can provide considerable insight into molecular mechanisms that underlie activation of the inflammation system in frailty. The short-term goal of this proposal is to establish initial preliminary data for specific modulations in inflammation-specific gene expression of isolated monocytes from frail older adults. The long-term goal of this project is to utilize these findings for the development of more in-depth etiologic and interventional studies of frailty. We hypothesize that frail older adults have significant alterations in constitutive and LPS-induced monocytic expression of genes encoding IL-6, TNF-alpha, IL-1beta, and IL-1 receptor antagonist (IL-1ra). The primary objectives of this proposal are to test this hypothesis and to further explore initial evidence for modulations in constitutive and LPS-induced monocytic expression of genes encoding 80 other cytokine mediators and cell surface molecules in the frailty syndrome. To accomplish these objectives, we propose an exploratory investigation (R21) into constitutive and LPS-induced monocytic expression of genes encoding 84 cytokine mediators and cell surface molecules in community-dwelling frail and non-frail older adults. A validated frailty-screening tool will be used to identify 15 age-, race-, and sex-matched pairs of frail and nonfrail older adults. Monocytes will be isolated and cultured in the presence and absence of LPS. Constitutive and LPS-induced monocytic gene expression will be evaluated and compared between frail and non-frail subjects, using a commercially available, inflammation-specific gene array containing cDNAs of IL-6, TNF-alpha, IL-1beta, IL-1ra, and 80 other cytokine mediators and cell surface molecules. Candidate genes with significant differences will be further evaluated by quantitative RT-PCR. This initial evaluation of the constitutive and LPS-induced monocytic expression of genes encoding IL-6, TNF-alpha, IL-1beta, IL-1ra will set the stage for more discerning mechanistic studies on monocytic production and regulation of these important cytokine mediators in frail older adults. This project will also explore initial evidence for modulations in constitutive and LPS-induced monocytic expression of genes encoding 80 other cytokine mediators and cell surface molecules in frail older adults. Therefore, It will serve as a hypothesis-generating project, and a basis for hypothesis refinement, that will open new pathways for future mechanistic and, potentially, interventional investigations of frailty in old age.