Cytokine-cytokine Receptor Interaction Pathway Research Articles

AB0191 Gene and Protein Expression Profile of Peripheral Blood in Primary Sjogren's Syndrome Patients

BackgroundSjogren syndrome (SS) is a chronic, multisystemic autoimmune disease characterized by lymphoplasmocytic infiltration of the salivary. Until now, its pathogenesis and diagnosis remain enigmatic. As a multisystem disease, it involves...

Transcriptome Analysis of Genes Regulated by Cholesterol Loading in Two Strains of Mouse Macrophages Associates Lysosome Pathway and ER Stress Response with Atherosclerosis Susceptibility

Cholesterol loaded macrophages in the arterial intima are the earliest histological evidence of atherosclerosis. Studies of mouse models of atherosclerosis have shown that the strain background can have a significant effect on lesion development. We have previously shown that DBA/2 ApoE−/− mice have aortic root lesions 10-fold larger than AKR ApoE−/−mice. The current study analyzes the response to cholesterol loading of macrophages from these two strains. Macrophages from the atherosclerosis susceptible DBA/2 strain had significantly higher levels of total and esterified cholesterol compared to atherosclerosis resistant AKR macrophages, while free cholesterol levels were higher in AKR cells. Gene expression profiles were obtained and data were analyzed for strain, cholesterol loading, and strain-cholesterol loading interaction effects by a fitted linear model. Pathway and transcriptional motif enrichment were identified by gene set enrichment analysis. In addition to observed strain differences in basal gene expression, we identified many transcripts whose expression was significantly altered in response to cholesterol loading, including P2ry13 and P2ry14, Trib3, Hyal1, Vegfa, Ccr5, Ly6a, and Ifit3. Eight pathways were significantly enriched in transcripts regulated by cholesterol loading, among which the lysosome and cytokine-cytokine receptor interaction pathways had the highest number of significantly regulated transcripts. Of the differentially regulated transcripts with a strain-cholesterol loading interaction effect, we identified three genes known to participate in the endoplasmic reticulum (ER) stress response, Ddit3, Trib3 and Atf4. These three transcripts were highly up-regulated by cholesterol in AKR and either down-regulated or unchanged in loaded DBA/2 macrophages, thus associating a robust ER stress response with atherosclerosis resistance. We identified significant transcripts with strain, loading, or strain-loading interaction effect that reside within previously described quantitative trait loci as atherosclerosis modifier candidate genes. In conclusion, we characterized several strain and cholesterol induced differences that may lead to new insights into cellular cholesterol metabolism and atherosclerosis.

Bioinformatics Method to Analyze the Mechanism of Pancreatic Cancer Disorder

Pancreatic cancer is an aggressive malignancy with a five-year mortality of 97-98% due to widespread metastatic disease. A better understanding of the molecular mechanism of pancreatic cancer is beneficial for the development of novel approaches for early detection and monitoring of pancreatic cancer. We aim to comprehensively identify the gene expression profile in pancreatic cancer and explore the molecular pathway of pancreatic cancer disorder. Using GSE15471 datasets downloaded from Gene Expression Omnibus data, we first screened the differentially expressed genes in pancreatic cancer using packages in R language. The key pathways of differentially expressed genes were investigated with the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis and synergetic network construction based on weighted Jaccard index. A total of 13,211 differentially expressed genes were identified, and they were enriched in several pathways, such as mitogen-activated protein kinase (MAPK) signaling pathway, transforming growth factor (TGF)-beta signaling pathway, Janus kinase-signal transducers and activators of transcription (JAK-STAT) signaling pathway, and calcium signaling pathway, as well as cell cycle, focal adhesion, complement and coagulation cascades, and leukocyte transendothelial migration. Synergetic pathway network analysis revealed that cytokine-cytokine receptor interaction pathway, calcium signaling pathway, and focal adhesion pathway were three important pathways in the development of pancreatic cancer. The method introduced here is helpful to screen the key pathways for controlling pancreatic cancer progression and provide potential therapeutic targets in the treatment of pancreatic cancer.

Gene Expression Profile of the Hippocampus of Rats Subjected to Chronic Immobilization Stress

ObjectiveThis study systematically investigated the effect of chronic stress on the hippocampus and its damage mechanism at the whole genome level.MethodsThe rat whole genome expression chips (Illumina) were used to detect gene expression differences in the hippocampus of rats subjected to chronic immobilization stress (daily immobilization stress for 3 h, for 7 or 21 days). The hippocampus gene expression profile was studied through gene ontology and signal pathway analyses using bioinformatics. A differentially expressed transcription regulation network was also established. Real-time quantitative polymerase chain reaction (RT-PCR) was used to verify the microarray results and determine expression of the Gabra1, Fadd, Crhr2, and Cdk6 genes in the hippocampal tissues.ResultsCompared to the control group, 602 differentially expressed genes were detected in the hippocampus of rats subjected to stress for 7 days, while 566 differentially expressed genes were expressed in the animals experiencing stress for 21 days. The stress significantly inhibited the primary immune system functions of the hippocampus in animals subjected to stress for both 7 and 21 days. Immobilization activated the extracellular matrix receptor interaction pathway after 7 day exposure to stress and the cytokine-cytokine receptor interaction pathway. The enhanced collagen synthesis capacity of the hippocampal tissue was the core molecular event of the stress regulation network in the 7-day group, while the inhibition of hippocampal cell growth was the core molecular event in the 21-day group. For the Gabra1, Fadd, Crhr2, and Cdk6 genes, RT-PCR results were nearly in line with gene chip assay results.ConclusionDuring the 7-day and 21-day stress processes, the combined action of polygenic, multilevel, and multi-signal pathways leads to the disorder of the immunologic functions of the hippocampus, hippocampal apoptosis, and proliferation disequilibrium.

Global endometrial transcriptomic profiling: transient immune activation precedes tissue proliferation and repair in healthy beef cows

BackgroundAll cows experience bacterial contamination and tissue injury in the uterus postpartum, instigating a local inflammatory immune response. However mechanisms that control inflammation and achieve a physiologically functioning endometrium, while avoiding disease in the postpartum cow are not succinctly defined. This study aimed to identify novel candidate genes indicative of inflammation resolution during involution in healthy beef cows. Previous histological analysis of the endometrium revealed elevated inflammation 15 days postpartum (DPP) which was significantly decreased by 30 DPP. The current study generated a genome-wide transcriptomic profile of endometrial biopsies from these cows at both time points using mRNA-Seq. The pathway analysis tool GoSeq identified KEGG pathways enriched by significantly differentially expressed genes at both time points. Novel candidate genes associated with inflammatory resolution were subsequently validated in additional postpartum animals using quantitative real-time PCR (qRT-PCR).ResultsmRNA-Seq revealed 1,107 significantly differentially expressed genes, 73 of which were increased 15 DPP and 1,034 were increased 30 DPP. Early postpartum, enriched immune pathways (adjusted P < 0.1) included the T cell receptor signalling pathway, graft-versus-host disease and cytokine-cytokine receptor interaction pathways. However 30 DPP, where the majority of genes were differentially expressed, the enrichment (adjusted P < 0.1) of tissue repair and proliferative activity pathways was observed. Nineteen candidate genes selected from mRNA-Seq results, were independently assessed by qRT-PCR in additional postpartum cows (5 animals) at both time points. SAA1/2, GATA2, IGF1, SHC2, and SERPINA14 genes were significantly elevated 30 DPP and are functionally associated with tissue repair and the restoration of uterine homeostasis postpartum.ConclusionsThe results of this study reveal an early activation of the immune response which undergoes a temporal functional change toward tissue proliferation and regeneration during endometrial involution in healthy postpartum cows. These molecular changes mirror the activation and resolution of endometrial inflammation during involution previously classified by the degree of neutrophil infiltration. SAA1/2, GATA2, IGF1, SHC2, and SERPINA14 genes may become potential markers for resolution of endometrial inflammation in the postpartum cow.

Gene expression analysis of host spleen responses to Marek's disease virus infection at late tumor transformation phase

Marek's disease is a viral neoplastic disease of chickens caused by Marek's disease virus (MDV). Gene expression patterns have been investigated at different MDV infection stages, but there is limited research about the late tumor transformation phase. In this experiment, 44K Agilent chicken genome-wide expression microarrays were used to profile differential expression in tumorous spleens (TS) from severely morbid chickens and apparently normal spleens from survivors (SS) after MDV infection and expression in noninfected spleens (NS) from controls. There were 4,317 differentially expressed (DE) genes in TS versus NS. However, no DE genes were detected in SS versus NS, suggesting that maintenance of, or return to, homeostasis of gene activity in survivor spleens. Downregulated genes in tumorous spleens mainly enriched in the cytokine-cytokine receptor interaction pathway, and commonly investigated genes in Marek's disease study, IL6, IL18, IFNA, and IFNG were nondifferentially expressed, which indicates host inflammatory response was impaired. The IL10 and TNFRSF8 genes were upregulated in tumorous spleens. We speculated that IL10 might be exploited by MDV to escape from host immune surveillance, as reported for Epstein-Barr virus, which stimulated T cells secreting IL10 to subvert immune response. Previous study reported that transcription from TNFRSF8 promoter could be enhanced by MDV oncogene Meq. In this study, the increased expression of TNFRSF8 indicated interaction between MDV and TNFRSF8, which might facilitate pathogenesis and tumor transformation. The expression of many members in IGF system was changed in tumorous compared with noninfected spleens. The downregulation of IGFBP7 was considered to be associated with MD lymphoma transformation. Gene expression change of multiple regulatory pathways indicated their involvements in facilitating tumor transformation.

Human Adipose Tissue Macrophages Display Activation of Cancer-related Pathways

Obesity is associated with a significantly increased risk for cancer suggesting that adipose tissue dysfunctions might play a crucial role therein. Macrophages play important roles in adipose tissue as well as in cancers. Here, we studied whether human adipose tissue macrophages (ATM) modulate cancer cell function. Therefore, ATM were isolated and compared with monocyte-derived macrophages (MDM) from the same obese patients. ATM, but not MDM, were found to secrete factors inducing inflammation and lipid accumulation in human T47D and HT-29 cancer cells. Gene expression profile comparison of ATM and MDM revealed overexpression of functional clusters, such as cytokine-cytokine receptor interaction (especially CXC-chemokine) signaling as well as cancer-related pathways, in ATM. Comparison with gene expression profiles of human tumor-associated macrophages showed that ATM, but not MDM resemble tumor-associated macrophages. Indirect co-culture experiments demonstrated that factors secreted by preadipocytes, but not mature adipocytes, confer an ATM-like phenotype to MDM. Finally, the concentrations of ATM-secreted factors related to cancer are elevated in serum of obese subjects. In conclusion, ATM may thus modulate the cancer cell phenotype.

Tumor-stroma interactions a trademark for metastasis

We aimed to unravel genes that are significantly associated with metastasis in order to identify functions that support disseminated disease. We identify genes associated with metastasis and verify its clinical correlations using publicly available primary tumor expression profile data sets. We used facilities in R and Bioconductor (GSEA). Specific data structures and functions were imported. Our results show that genes associated with metastasis in primary tumor enriched for pathways associated with immune infiltration or cytokine-cytokine receptor interaction. As an example, we focus on the enrichment of TGFBR2 and TGF|X A set of communication tools capital for tumor-stroma interactions that define metastasis to the lung and support bone colonization. We showed that tumor-stroma communication through cytokine-cytokine receptor interaction pathway is selected in primary tumors with high risk of relapse. High levels of these factors support systemic instigation of the far metastatic nest as well as local metastatic-specific functions that provide solid ground for metastatic development.

Tissue‐engineered cartilage of porcine and human origin as in vitro test system in arthritis research

The increasing prevalence of cartilage destruction during arthritis has entailed an intensified amount for in vitro cartilage models to analyze pathophysiological processes and to screen for antirheumatic drugs. Tissue engineering offers the opportunity to establish highly organized 3D cell cultures facilitating the formation of in vitro models that reflect the human situation. We report the comparison of porcine chondrocyte pellet and alginate bead cultures as model systems for human cartilage and the further development into a human system that was applied in an arthritis model. In porcine pellet and alginate cultures, formation of cartilage matrix similar to human matrix was verified by histology and PCR. As alginate beads could be cultivated batch-wise in one well of a multiwell plate, we further developed this setting into a human system. In contrast, each pellet had to be cultivated individually in one well of a multiwell plate, which is time consuming. Following stimulation of human chondrocyte alginate cultures with conditioned media from human synovial fibroblasts derived from arthritis patients, microarray analysis verified the induction of genes related to cartilage destruction (like MMP10, -12) and inflammation (like IL6, -8 and chemokines). Several genes are coding for proteins that are members of inflammatory and catabolic pathways. Belonging to the most affected pathways, we identified the focal adhesion, cytokine-cytokine receptor interaction, ECM-receptor signalling, Jak-STAT signalling, and toll-like receptor signalling pathways, all relevant in arthritis. Therefore, we demonstrate that engineered cartilage of porcine and human origin represents a powerful in vitro model for cartilage in vivo.

Abstract 2170: Genomic profiling and pathway significances of natural killer cell lymphoma (NKL): Implication for NK lymphomagenesis and genomic targeting therapeutics

Abstract Natural killer cell lymphoma (NKL) is a highly aggressive form of lymphoid malignancy (Suzuki et al. BLOOD 2009). We hypothesized that the comparison of differentially expressed genes of NKL vs normal NK cells would be a rational approach for enhancing our understanding of NK lymphomagenesis and lead to the discovery of genomic markers and potential therapeutic targets. Isolated RNA from highly enriched peripheral blood NK cells (CD3-, CD56+; PBNK) and human IL2-independent NKL cell line (NK-92MI) were subjected to microarray studies using Affymetrix U133A_2. Gene data were subjected to Agilent GeneSpring analyses. Welch test were used to perform statistical analysis and fold change of &amp;lt; 2.0 and values of p&amp;lt;0.05 were considered to be significant. NK-92MI NKL vs PBNK expressed high CD3ε (3.4F UP), presumably due to the constitutive expression of IL-2 in NK-92MI. The gene array studies identified 1284 genes that were upregulated (&amp;gt;2F) and 1558 genes that were downregulated (&amp;gt;2F) in NKL vs PB NKs. The pathway mapping studies identified 22 pathways (p&amp;lt;0.05), including cytokine-cytokine receptor interaction (CCRI) (12 genes), pathways in cancer (PIC) (26 genes) and p53 signaling (13 genes), involved in up-regulation, whereas 26 pathways (p&amp;lt;0.05), including antigen processing and presentation (APP) (12 genes), CCRI pathway (29 genes), and MAPK signaling (36 genes), involved in down-regulation. Altered genes in CCRI pathway included CCL18 (1257F UP), CXCL2 (583F DOWN), IL7R (379F DOWN), TNFRSF25 (276F DOWN), IL1B (198F DOWN), CX3CR1 (181F DOWN). Altered genes in MAPK pathway included DUSP4 (330F DOWN), IL1B (198F DOWN), CD14 (120F DOWN), CACNA2D2 (51F DOWN). Altered genes in p53 pathway included IGF1 (465F UP), RRM2 (144F UP), CDKN2A (56F UP). Altered genes in PIC pathway included BIRC5 (117F UP), FN1 (73F UP), RALBP1 (158F DOWN), TCF7L2 (137F DOWN), CTBP2 (122F DOWN), PTK2 (107F DOWN). NK cell mediated cytotoxicity pathway was not significantly changed (p &amp;lt;0.2). However, 16 and 9 genes were demonstrated to be up and down regulated, including NCR2 (211F UP), NFATC1 (100F DOWN), DAP-12/TYROBP (64F DOWN), and IFNGR2 (40F DOWN). CCL18 chemokine is a known non-invasive biomarker in many diseases. Granzyme protein, which activates caspase-3 (CASP3), was down-regulated in NKL. BIRC5 (survivin) gene, which inhibits CASP3, was increased in NKL. CASP3 and BIRC5 counteract a default induction of apoptosis in G2/M phase. NCR2 and DAP-12 specifically regulate NK mediated cytotoxicity. These data suggest that CCRI, p53, APP, and MAPK signaling pathways may be involved in NK lymphomagenesis. The 108 altered genes in these pathways may serve in part to characterize the genetic signature in NKL. Furthermore, CCL18, NCR2, BIRC5, and DAP-12 together may serve as genomic markers to identify NKL and may be candidate targets for novel therapeutics. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2170.

Altered profiles of gene expression in curcumin-treated rats with experimentally induced myocardial infarction

Curcumin has extensive cardioprotective effects against diabetic cardiovascular complications, cardiac hypertrophy and myocardial infarction (MI), but the molecular mechanism behind such cardioprotective effects remains still unclear. To explore the mechanism of MI, a rat model of coronary artery ligation was used to assess the cardioprotective effects of curcumin. Microarray technology was employed to detect the gene expression in the heart of MI rats treated with curcumin. Semiquantitative RT-PCR was then performed to verify the microarray result. Our results showed that curcumin could improve heart function, diminish infarct size and reverse the abnormal changes in the activities of serum lactate dehydrogenase and creatine kinase MB in rats after MI. A total of 179 genes were found to be significantly differentially expressed between sham-operated rats and coronary artery-ligated rats. Cytokine-cytokine receptor interaction, ECM-receptor interaction, focal adhesions and colorectal cancer pathway may be involved in the cardioprotective effects of curcumin.

Identification of molecular checkpoints in patients with prostate cancer immunized with PSA146-154 peptide vaccine (41.24)

Abstract The objective of the current study is to delineate genes that may be differentially expressed in responding versus non responding patients in the context of a completed PSA146-154 peptide vaccine protocol. 28 HLA-A2+ prostate cancer patients with high risk, local disease or metastatic, hormone sensitive disease in remission were vaccinated on weeks 1, 4, and 10 with peptide plus GM-CSF or peptide loaded autologous DC. Before and after PBMC were assessed for specific tetramer response and gene expression profiles per Affymetrix whole human genome arrays. Clinical status was evaluated per serial serum PSA. 13 of 27 patients achieved stable serum PSA (1 not evaluable), of whom 9 patients developed specific tetramer responses at six months post first vaccination. Thus the detectable immunity was associated with lower risk of PSA progression (p=0.02). Comparison of array data between responders and non responders indicated that 114 of 54,675 genes were differentially expressed (p&amp;lt;0.001). Notably VEGF-A, LIF, TNFRSF21 and IFNK, pertaining to the cytokine-cytokine receptor interaction pathway were predicted to be impacted (Impact factor=5.19). Taqman gene assays indicated that the expression of VEGF-A relative to GAPDH was greater in non responding compared to responding patients. Hence, VEGF-A is one of the likely candidates to impede vaccine efficacy, possibly by mediating its effects on antigen presenting cells.

Characterization of the acute temporal changes in excisional murine cutaneous wound inflammation by screening of the wound-edge transcriptome

This work represents a maiden effort to systematically screen the transcriptome of the healing wound-edge tissue temporally using high-density GeneChips. Changes during the acute inflammatory phase of murine excisional wounds were characterized histologically. Sets of genes that significantly changed in expression during healing could be segregated into the following five sets: up-early (6-24 h; cytokine-cytokine receptor interaction pathway), up-intermediary (12-96 h; leukocyte-endothelial interaction pathway), up-late (48-96 h; cell-cycle pathway), down-early (6-12 h; purine metabolism) and down-intermediary (12-96 h; oxidative phosphorylation pathway). Results from microarray and real-time PCR analyses were consistent. Results listing all genes that were significantly changed at any specific time point were further mined for cell-type (neutrophils, macrophages, endothelial, fibroblasts, and pluripotent stem cells) specificity. Candidate genes were also clustered on the basis of their functional annotation, linking them to inflammation, angiogenesis, reactive oxygen species (ROS), or extracellular matrix (ECM) categories. Rapid induction of genes encoding NADPH oxidase subunits and downregulation of catalase in response to wounding is consistent with the fact that low levels of endogenous H2O2 is required for wound healing. Angiogenic genes, previously not connected to cutaneous wound healing, that were induced in the healing wound-edge included adiponectin, epiregulin, angiomotin, Nogo, and VEGF-B. This study provides a digested database that may serve as a valuable reference tool to develop novel hypotheses aiming to elucidate the biology of cutaneous wound healing comprehensively.

Combined oligonucleotide microarray-bioinformatics and constructed membrane arrays to analyze the biological pathways in the carcinogenesis of human lung adenocarcinoma

The present study systematically explores the biological pathways and altered expression of genes speculatively participating in lung carcinogenesis by using oligonucleotide microarray-bioinformatic analysis methods. The results revealed that 1,396 genes were up-regulated and 1,965 were down-regulated in lung adenocarcinoma carcinogenesis. Gene ontology and relevant bioinformatics tools indicated that the functional category to which the most frequently differentially expressed genes were classified, was to the cytokine-cytokine receptor interaction pathway, focal adhesion pathway and the mitogen-activated protein kinase signaling pathway. Furthermore, we constructed a membrane array, consisting of 51 up-regulated genes in lung adenocarcinoma, in order to verify the biological pathways involved in the carcinogenesis of lung cancer. The analysis of 45 lung adenocarcinoma tissue specimens demonstrated that the genes involved in these three biological pathways had high rates of overexpression. Out of the 51 genes, 17 genes were demonstrated to be overexpressed in all 45 lung adenocarcinoma tissues compared to the paired normal lung tissues. These findings could have implications in understanding the process of lung adenocarcinoma carcinogenesis. Moreover, our developed membrane arrays could be a potentially feasible and promising tool in clinical practice for analyzing the molecular mechanisms of lung adenocarcinoma carcinogenesis.

Understanding ZHENG in traditional Chinese medicine in the context of neuro-endocrine-immune network

Traditional Chinese medicine uses ZHENG as the key pathological principle to understand the human homeostasis and guide the applications of Chinese herbs. Here, a systems biology approach with the combination of computational analysis and animal experiment is used to investigate this complex issue, ZHENG, in the context of the neuro-endocrine-immune (NEI) system. By using the methods of literature mining, network analysis and topological comparison, it is found that hormones are predominant in the Cold ZHENG network, immune factors are predominant in the Hot ZHENG network, and these two networks are connected by neuro-transmitters. In addition, genes related to Hot ZHENG-related diseases are mainly present in the cytokine-cytokine receptor interaction pathway, whereas genes related to both the Cold-related and Hot-related diseases are linked to the neuroactive ligand-receptor interaction pathway. These computational findings were subsequently verified by experiments on a rat model of collagen-induced arthritis, which indicate that the Cold ZHENG-oriented herbs tend to affect the hub nodes in the Cold ZHENG network, and the Hot ZHENG-oriented herbs tend to affect the hub nodes in the Hot ZHENG network. These investigations demonstrate that the thousand-year-old concept of ZHENG may have a molecular basis with NEI as background.

Gene expression profile in obesity and type 2 diabetes mellitus

Obesity is an important component of metabolic syndrome X and predisposes to the development of type 2 diabetes mellitus. The incidence of obesity, type 2 diabetes mellitus and metabolic syndrome X is increasing, and the cause(s) for this increasing incidence is not clear. Although genetics could play an important role in the higher prevalence of these diseases, it is not clear how genetic factors interact with environmental and dietary factors to increase their incidence. We performed gene expression profile in subjects with obesity and type 2 diabetes mellitus with and without family history of these diseases. It was noted that genes involved in carbohydrate, lipid and amino acid metabolism pathways, glycan of biosynthesis, metabolism of cofactors and vitamin pathways, ubiquitin mediated proteolysis, signal transduction pathways, neuroactive ligand-receptor interaction, nervous system pathways, neurodegenerative disorders pathways are upregulated in obesity compared to healthy subjects. In contrast genes involved in cell adhesion molecules, cytokine-cytokine receptor interaction, insulin signaling and immune system pathways are downregulated in obese. Genes involved in signal transduction, regulation of actin cytoskeleton, antigen processing and presentation, complement and coagulation cascades, axon guidance and neurodegenerative disorders pathways are upregulated in subjects with type 2 diabetes with family history of diabetes compared to those who are diabetic but with no family history. Genes involved in oxidative phosphorylation, immune, nervous system, and metabolic disorders pathways are upregulated in those with diabetes with family history of diabetes compared to those with diabetes but with no family history. In contrast, genes involved in lipid and amino acid pathways, ubiquitin mediated proteolysis, signal transduction, insulin signaling and PPAR signaling pathways are downregulated in subjects with diabetes with family history of diabetes. It was noted that genes involved in inflammatory pathway are differentially expressed both in obesity and type 2 diabetes. These results suggest that genes concerned with carbohydrate, lipid and amino acid metabolic pathways, neuronal function and inflammation play a significant role in the pathobiology of obesity and type 2 diabetes.