开题报告内容：（包括拟研究或解决的问题、采用的研究手段及文献综述，不少于2000字）Background:TNF-alpha; is an inflammatory cytokine that plays an important role in insulin resistance observed in obesity and chronic inflammation. Many cellular components involved in insulin signaling cascade are known to be inhibited by TNF-alpha;. Insulin receptor substrate (IRS)-1 is one of the major targets in TNF-alpha;-induced insulin resistance. The serine phosphorylation of IRS-1 enables the inhibition of insulin signaling. Until now, many studies have been conducted to investigate the mechanism of TNF-alpha;-induced insulin resistance based on Western blot. Intracellular protein kinase crosstalk is commonly encountered in inflammation-associated insulin resistance. The crosstalk among the signaling molecules obscures the precise role of kinases in insulin resistance. The aim of the study is to develop a cell lysis-free quantum dots (QDots) multicolor cellular imaging to identify the biochemical role of multiple kinases (p38, JNK, IKKbeta;, IRS1ser, IRS1tyr, GSK3beta;, and FOXO1) in inflammation-associated insulin resistance pathway with a single assay in one run. QDot-antibody conjugates will be used as nanoprobes to simultaneously monitor the activation/ deactivation of the above seven intracellular kinases in HepG2 cells. The effect of the test compounds on the suppression of TNF-alpha;-induced insulin resistance will be validated through kinase monitoring. Aspirin, indomethacin, cinnamic acid, and amygdalin will be tested.Methods: Cell culture Western blot QDot-antibody nanoprobe based multicolor imaging using AOTF microscope. Literature Review:Insulin resistance means that cells fail to respond normally to the hormone insulin, resulting in the disability of glucose uptake and metabolism. People who develop type 2 diabetes or obesity pass through earlier stages of insulin resistance and prediabetes. The adipocytes of obese patients excrete many kinds of cytokines involved in insulin signaling cascade, including TNF-alpha;, IL-6, Leptin and so on. Among them, TNF-alpha; is an inflammatory cytokine that plays an important role in insulin resistance. Hence, the present review summarizes the relationships between TNF-alpha; and insulin resistance.1.The structure and bioactivity of TNF-alpha;TNF was discovered in 1975 as an endotoxin-inducible molecule that caused necrosis of tumors in vitro [1]. TNF is a transmembrane 26 KDa protein expressed by activated monocytes/ macrophages (including central nervous system (CNS) microglia), activated NK and T cells, but also by a diverse array of non-immune cells such as endothelial cells and fibroblasts [2,3]. As a transmembrane protein expressed on the surface of cells, membrane TNF (also sometimes referred to as pro-TNF) is cleaved by a metalloprotease, TNFa-converting enzyme (TACE) [4,5]. Both soluble and membrane TNF bind to two transmembrane receptor molecules: TNFR1 (also sometimes referred to a p55/p60) a death-domain-containing protein, and TNFR2 (also known as p75/p80) [6] (see Fig. 1). A review of TNFR signaling must also consider that TNF ligation of TNFRs also leads to non-apoptotic and non-proliferative signaling pathways. These include acid and neutral sphingomyelinase pathways and the activation of 5-lipoxygengase and phospholipase A2 enzymes, that result in the production of arachindonic acid, 5-hydroxyeicosatetraenoic acid (5-HETE) and proinflammatory leukotrienes [7]. The sphingomylinase pathway leads to the production of diacyl glycerol and subsequently to the activation of protein kinase C, and eventually NF-kB (independent of TRAF-activated NF-kB [8,9]). This results in the expression of pro-inflammatory cytokines and chemokines but also in production of prostaglandins [10]. There is also the recruitment of a molecule known as Fas-associated with neutral sphingomyelinase (FAN), to a membrane proximal domain in TNFRs [11], and the actions of acid sphingomylinase that result in production of ceramides. Ceramides induce active cathepsin D, an aspartate non-caspase protease that can target BID [12,13]. Thus FAN connects the TNFR biology to the plasma membrane, and more specifically, to cytoskeletal re-organisation, filopodium formation, and macropinocytosis [14], and hence to processes of leukocyte migration [15]. Ceramide is also a powerful inflammatory intermediate involved in several cellular processes including cell migration, proliferation, and apoptosis (for review see [16]). Thus, the effects of TNF-induced TNFR signaling pathways are diverse, and varied in different cell types, and specific circumstances explaining TNFs pleiotropic properties. 2.The overexpression of TNF-alpha; in insulin resistenceTNF-alpha; derived from adipocytes in the beginning. But the main source is macrophage in the adipocytes. Insulin resistance can show up in the condition of cancer, infection, burn and so on, meanwhile, the level of TNF-alpha;rises correspondingly. In genetically obese model mice with insulin resistance, the expression of TNF-alpha; increases and the insulin resistance improves when the TNFalpha;-antibody adding. In the TNF-alpha; gene knocked obese model mice, skeletal muscle cell insulin sensitivity has improved observably. A cohort study shows that the increase of TNF-alpha; expression always comes with insulin resistance and metabolism syndrome. TNF-alpha; is a single danger factor of insulin resistance. Another study shows that expression of TNF-alpha; is in positive proportion to BMI index and hyperinsulinemia. And the level of TNF-alpha; goes down when the weight was lost. There are also reports saying that expression of TNF-alpha; goes up in the adipose tissue of the obese patients, working closely with empty stomach insulin level. The serum TNF-alpha; level increases in the obese Type 2 diabetes mellitus patients, in positive proportion to visceral fat content, which reduces observably after the treatment through diet and exercise. A group of rheumatoid arthritis patients clinical research reports that after long term administration (24 weeks) of TNF-alpha; inhibitor, the HOMA index reduces notably and the insulin resistance improved dramatically. 3.The mechanism of TNF-alpha; induced insulin resistanceFor the most of obese and Type 2 diabetes mellitus patients, the defect of signal transduction pathway after target cell insulin receptor is the molecular mechanism of insulin resistance. The insulin resistance inducted by inflammatory cytokines mainly worked through the serine phosphorylation of insulin receptor substrate (IRS), inhibiting the normal tyrosine phosphorylation of IRS. As a result, the combination between IRS and insulin becomes weaker. This can also recede the IRS activating the downstream phosphorylation of PI3K and interferes insulin signal transduction through IR, IRS and PI3K. 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