CBL2117 Sigma-AldrichAnti-Interleukin-6 Antibody, clone B-E8

Puerarin is an isoflavonoid isolated from the root of the plant Pueraria lobata and has been used as a prescribed drug in China for the treatment of cardiovascular diseases in the clinical practice. Puerarin possesses potential therapeutic activities for metabolic and cardiovascular disorders. However, little is yet known about its bioprotection against endothelial dysfunction insulin resistance involved. In this study, we established insulin resistance by palmitate stimulation in the endothelium and investigated the action of puerarin on the modulation of insulin sensitivity under the insulin resistant condition. Palmitate stimulation impaired insulin-mediated vasodilation in the rat aorta and puerarin treatment effectively restored the impaired vasodilation in a concentration-dependent manner (1, 10 and 50 μM). Palmitate stimulation evoked inflammatory response in endothelial cells. Puerarin inhibited IKKβ/NF-κB activation and decreased TNF-α and IL-6 production with the downregulation of relative gene overexpression. Palmitate stimulation impaired the insulin PI3K signaling pathway and reduced insulin-mediated NO production in endothelial cells. Puerarin attenuated PA-induced phosphorylation of insulin receptor substrate-1 (IRS-1) at S307 and effectively ameliorated insulin-mediated tyrosine phosphorylation of IRS-1. The beneficial modification of serine/tyrosine phosphorylation of IRS-1 restored downstream Akt/eNOS activation, and thereby increased insulin-mediated NO production. These results suggest that puerarin inhibits inflammation and attenuates endothelial insulin resistance in an IKKβ/IRS-1-dependent manner.

Maternal immune activation during prenatal development, including treatment with the viral RNA mimic, polyriboinosinic-polyribocytidilic acid (poly IC), serves as a widely used animal model to induce behavioral deficits reminiscent of schizophrenia and related disease. Here, we report that massive cytokine activation after a single dose of poly IC in the prenatal period is associated with lasting working memory deficits in adult offspring. To explore whether dysregulated gene expression in cerebral cortex, contributes to cognitive dysfunction, we profiled the cortical transcriptome, and in addition, mapped the genome-wide distribution of trimethylated histone H3-lysine 4 (H3K4me3), an epigenetic mark sharply regulated at the 5' end of transcriptional units. However, deep sequencing-based H3K4me3 mapping and mRNA profiling by microarray did not reveal significant alterations in mature cerebral cortex after poly IC exposure at embryonic days E17.5 or E12.5. At a small set of genes (including suppressor of cytokine signaling Socs3), H3K4me3 was sensitive to activation of cytokine signaling in primary cultures from fetal forebrain but adult cortex of saline- and poly IC-exposed mice did not show significant differences. A limited set of transcription start sites (TSS), including Disrupted-in-Schizophrenia 1 (Disc1), a schizophrenia risk gene often implicated in gene-environment interaction models, showed altered H3K4me3 after prenatal poly IC but none of these differences survived after correcting for multiple comparisons. We conclude that prenatal poly IC is associated with cognitive deficits later in life, but without robust alterations in epigenetic regulation of gene expression in the cerebral cortex.

Berberine, a major isoquinoline alkaloid present in Chinese herb Rhizoma coptidis, is a potent inhibitor of inflammation and has anti-diabetic activity. This study aims to investigate effects of berberine on ameliorating insulin resistance and molecular mechanisms involved in HepG2 cells. Inflammatory responses and insulin resistance were induced by palmitate (PA) stimulation for 24 h. Treatment of berberine enhanced insulin-mediated glycogen synthesis and restored insulin inhibition of triglyceride secretion. Stimulation of PA resulted in IL-6 and TNF-? production in HepG2 cells, and antibody-neutralizing assay further confirmed that IL-6 and TNF-? were involved in the development of insulin resistance. Berberine effectively inhibited IL-6 and TNF-? production in a concentration-dependent manner, demonstrating its anti-inflammatory activity in hepatocytes. Meanwhile, PA-evoked inflammation impaired insulin signaling cascade and berberine improved insulin signaling cascade by modification of Ser/Thr phosphorylation of insulin receptor substrate-1(IRS-1) and downstream Akt (T308). Above results suggest that berberine improved insulin sensitivity in PA-stimulated hepatocytes and this regulation might relative with its anti-inflammatory activity.

Following retinal degeneration or inflammation that disrupts tissue architecture, there is limited evidence of tissue regeneration, despite evidence of cells with progenitor properties in the adult human retina at all ages. With the prospect of tissue/cell transplantation, redressing homeostasis whilst overcoming glial barrier or gliosis remains key to successful graft versus host integration and functional recovery. Activated human retinal microglia (MG) secrete cytokines, including IL-6, which may suppress neurogenesis or cellular (photoreceptor) replacement. To investigate this hypothesis, adult human retinal explants were cultured in cytokine-conditioned media (TNFalpha, TGFbeta, LPS/IFNgamma) to activate microglia in situ. Following culture of retinal explants for 4 days, supernatant conditioned by resulting migrated microglia was collected after a further 3 days and fed to retinal cell suspensions (RCS). Neurosphere (NS) generation and survival analysis was performed after 7 and 14 days in culture, with or without addition of conditioned media and with or without concomitant IL-6 neutralisation. Neurosphere phenotype was analysed by immunohistochemistry and cell morphology. Migratory MG from retinal explants were activated (iNOS-positive) and expressed CD45, CD11b, and CD11c. LPS/IFNgamma-activated MG conditioned media (MG-CM) contained significant levels of IL-6 (1265 +/- 143) pg/ml, which inhibited neurosphere generation within RCS in the presence of optimal neurosphere generating N2-FGF2 culture medium. Neutralising IL-6 activity reinstated NS generation and the differentiation capacity was maintained in the spheres that formed. Even in the presence of high levels of IL-6, those few NS that did form demonstrated a capacity to differentiate. The data supports activated MG-derived IL-6 influence retinal cell turnover.

Interleukin-6 (IL-6) is produced by many different cell types. Human skeletal muscles produce and release high amounts of IL-6 during exercise; however, the cell source of origin in the muscle is not known. Therefore, we studied the protein expression of IL-6 by immunohistochemistry in human muscle tissue from biopsies obtained at time points 0, 3, 4.5, 6, 9, and 24 h in relation to 3 h of bicycle exercise performed by healthy young males (n=12) and in resting controls (n=6). The IL-6 expression was clearly increased after exercise and remained high even by 24 h, relative to pre-exercise or resting individuals. The IL-6 immunostainings of skeletal muscle cells were homogeneous and without difference between muscle fiber types. The IL-6 mRNA peaked immediately after the exercise, and, in accordance, the IL-6 protein expression within muscle cells was most pronounced around 3 h post-exercise. However, the finding that plasma IL-6 concentration peaked in the end of exercise indicates a high turnover of muscle-derived IL-6. In conclusion, the finding of marked IL-6 protein expression exclusively within skeletal muscle fibers following exercise demonstrates that skeletal muscle fibers of all types are the dominant cell source of exercise-induced release of IL-6 from working muscle.

The aim of this study was to test the hypothesis that systemic inflammation in patients with chronic obstructive pulmonary disease (COPD) is accompanied by enhanced interleukin 18 (IL-18) expression in skeletal muscle, which may precede muscle weight loss. Twenty patients with moderate to severe COPD [12 women, 66 +/- 9.4 years of age and forced expiratory volume in 1 second (FEV(1)) of 32% +/- 12 % of predicted value] and 20 healthy age-, gender-, and body mass index (BMI)-matched controls (10 nonsymptomatic smokers and 10 nonsmokers) were included in the study. Plasma levels of IL-18 were elevated in COPD patients (n = 20) versus healthy controls (n = 20) (221.2 pg/ml [196.0-294.2 pg/pl] vs. 164.8 pg/ml [144.4-193.3 pg/pl], p = 0.05) [corrected] and IL-18 was expressed in skeletal muscle, with IL-18 mRNA levels being elevated in biopsies from COPD patients (n = 19) versus healthy controls (n = 18) (4.3 [2.6-5.9] vs. 2.4 [1.6-3.1], p = 0.05) [corrected]. Immunohistochemical evaluation revealed a strong expression of IL-18 in Type II muscle fibers from COPD patients. Plasma levels and skeletal muscle mRNA levels of tumor necrosis factor alpha (TNF-alpha) and IL-6 did not differ between the groups. Elevated skeletal muscle expression of IL-18 was found in COPD patients with normal body weight, indicating that IL-18 potentially may be involved in the pathogenesis of COPD-associated muscle wasting.