Insulin enhancement of cytokine-induced coagulation/inflammation-related gene transcription in hepatocytes

Identification and characterization of a nuclear factor-κ B-p65 proteolytic fragment in nuclei of porcine hepatocytes in monolayer culture

Hepatic responses to proinflammatory signals are controlled by the activation of several transcription factors, including, nuclear factor-κ B (NF-κB). In this study, hepatocytes prepared from suckling pigs and maintained in serum-free monolayer culture were used to define a novel proinflammatory cytokine-specific NF-κB subunit modification. The immunoreactive p65 protein was detected by Western blot analysis at the appropriate molecular weight in the cytosol of control cultures and those incubated with tumor necrosis factor-α (TNF). However, in nuclei, the p65 antisera cross-reacted with a protein of approximately 38 kDa (termed p38) after TNF addition, which was not observed in the cytosol of control or cytokine-treated cells. Specifically, incubation with TNF also resulted in phosphorylation (P < 0.05) of the inhibitor complex protein (IκB), whereas incubation with other cytokines, IL-6, IL-17a, or oncostatin M was not associated with either phosphorylation of IκB or nuclear translocation of p65. Intracellular endothelial nitric oxide synthase was deceased (P < 0.05) and plasminogen activator inhibitor-1 secretion was increased (P < 0.05) after TNF incubation. The TNF-induced p38 protein was purified from hepatocyte nuclei by immunoprecipitation, concentrated by electrophoresis, and subsequently analyzed by mass spectrometry. Ten unique NF-κB p65 peptides were identified after digestion with trypsin and chymotrypsin; however, all were mapped to the N-terminus and within the first 310 amino acid residues of the intact p65 protein. Although low molecular weight immunoreactive p65 molecules were previously observed in various human and rodent systems, this is the first report to positively identify the p38 fragment within hepatocyte nuclei or after specific cytokine (TNF) induction.

Gender specifics of the association between blood fibrinolytic activity and cardiovascular disease or diabetes mellitus in a cohort of Muscovites aged 55 years or older

Aim. To investigate potential gender differences in the association between plasma fibrinolytic activity (FLA) and atherosclerotic pathology in elderly people. Material and methods. This analysis was performed as a part of the prospective population-based cohort study “Stress, Ageing, and Health in Russia”. The study included randomly selected Moscow residents of both genders and age of ≥55 years (n=1863; 889 men and 974 women). Based on the levels of blood FLA (time of spontaneous lysis of euglobin blood fraction, or euglobin lysis time, ELT), all participants were divided into three groups: with normofibrinolysis (ELT 180-260 minutes), hypofibrinolysis (ELT >260 minutes), and hyperfibrinolysis (ELT <180 minutes). Results. In this cohort of elderly Muscovites, the association between FLA and the presence of cardiovascular disease (CVD) or Type 2 diabetes mellitus (DM-2) differed in men and women. The link between hypofibrinolysis, atherogenic changes in lipid profile, or high fasting levels of insulin and arterial hypertension (AH), myocardial infarction (MI), or DM-2 was present only in men. In women, either reduced or increased FLA was not related to DM-2. Men with hyperfibrinolysis demonstrated lower odds of AH and DM-2, while women with hyperfibrinolysis had lower odds of AH, coronary heart disease, or angina. Conclusion. In elderly people, high FLA appears to provide protection against atherothrombotic pathology, regardless of gender. Low FLA was associated with higher odds of CVD and DM-2 in men only.

Patients with insulin-dependent diabetes or coronary heart disease following rehabilitation express serum fractalkine levels similar to those in healthy control subjects

The chemokine and adhesion molecule fractalkine and its receptor CX₃CR1 have emerged as interesting regulators in inflammation and related atherosclerosis. The pro-inflammatory status may be counteracted by appropriate treatment, such as in rehabilitation. We compared serum fractalkine concentrations of 46 patients with coronary heart disease (CHD) and 47 insulin-dependent diabetic patients (IDDM) following rehabilitation with those of 50 control subjects. Following rehabilitation serum fractalkine levels (477 ± 225 pg/mL) in CHD patients were similar to those in control subjects (572 ± 205 pg/mL; P = 0.303), whereas fractalkine levels were lower in IDDM patients (430 ± 256 pg/mL; P = 0.042). No significant difference between CHD and IDDM patients was present (P = 0.319). Postprandial hyperlipemia may influence inflammation; thus, we investigated fractalkine levels four and eight hours after inducing postprandial hyperlipemia. However, we did not find any significant alterations in CHD and diabetic patients, whereas the fractalkine levels in controls were reduced. In vitro, lipofundin used as a hyperlipemic stimulus was added to vessel wall cells and reduced fractalkine levels. Low fractalkine levels in patients attending rehabilitation indicate a beneficial effect of the rehabilitation procedure on innate inflammatory pathways, such as the chemokine and adhesion molecule fractalkine.