ABSTRACT
Chronic lymphocytic leukemia is characterized by the accumulation of functionally abnormal, monoclonal B lymphocytes in the peripheral blood, bone marrow, lymph nodes and spleen, resulting in a reduction count of normal immunocompetent cells and their impaired immune function. The defect in transmission of signals from various types of extracellular receptors, leading to aberrant cytokines and transcription factors gene expression, may underlie the basis of immune failure in B-CLL. The aim of the study was to assess of IL-6, IL-10, c-Jun, and STAT3 expression. In response to antigenic stimulation IL-6, IL-10, c-Jun, and STAT3 proteins induce mutual activity. The subject of the study was subpopulations of leukemic lymphocytes (CD5+ CD19+) and CD19+ B cells from healthy donors (control group). Our results provide evidence that the regulation of IL-6, IL-10, c-Jun, and STAT3 gene expression in CLL B cells is clearly different from normal B lymphocytes. In B-CLL STAT3 expression in unstimulated lymphocytes is significantly higher (p<0.0001) compared with normal subpopulation of B cell. In contrast, IL-6, IL-10, and c-Jun mRNA expressions are statistically lower in B-CLL in comparison with the control group, in all cases (p<0.0001). When analyzing the relationship between c-Jun expression and B-CLL stage according Rai we revealed decreasing c-Jun expression, both at the mRNA and protein levels, along with advancing stage of disease.
Subject(s)
Interleukin-10/genetics , Interleukin-6/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Proto-Oncogene Proteins c-jun/genetics , STAT3 Transcription Factor/genetics , Aged , Aged, 80 and over , B-Lymphocytes/metabolism , B-Lymphocytes/pathology , Female , Gene Expression Regulation, Leukemic , Humans , Interleukin-10/analysis , Interleukin-6/analysis , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Male , Middle Aged , Proto-Oncogene Proteins c-jun/analysis , RNA, Messenger/genetics , STAT3 Transcription Factor/analysisABSTRACT
In this study we investigate the mechanisms underlying gender differences in the generation of arrhythmias in the long QT and Brugada syndromes. Simulations were conducted at the single myocyte level using a detailed mathematical model of human ventricular myocytes. Given the scarce human data on the gender-related differences in single cardiac cells, we assumed gender-related differences in five ionic-current systems: fast sodium current (INa), slowly inactivating late sodium current (INal), transient outward potassium current (Ito), slow delayed rectifier potassium current (IKs), and calcium current through the L-type channel (ICa(L)), based on experimental results obtained in canine myocytes. Our modeling results suggest that in left ventricular myocytes, enhanced INal under conditions of reduced repolarization reserve results in sex-dependent development of early afterdepolarizations (EADs) in the post-pause action potentials (APs). Moreover, this modeling study demonstrates increased propensity for the development of the loss of the AP dome in male epicardial myocytes of the right ventricle compared with other types of myocytes from the left and right ventricles. Finally, we also found a slight effect of INal on gender-dependent loss of AP dome in epicardial right ventricular myocytes. In conclusion, at the cellular level, gender differences in the development of EADs and the propensity to develop the loss of the AP dome can be attributed to male/female related differences in INa, INal, Ito, IKs, and ICa(L).
Subject(s)
Heart/physiology , Models, Cardiovascular , Myocytes, Cardiac/physiology , Action Potentials/physiology , Algorithms , Calcium/metabolism , Computer Simulation , Female , Heart Ventricles/cytology , Humans , Male , Myocytes, Cardiac/metabolism , Pericardium/cytology , Potassium/metabolism , Sex Factors , Sodium/metabolismABSTRACT
TIRAP and Myd88 are adaptor proteins for Toll-like receptors-2 and -4 (TLR2/4) which are engaged in transducing the signal to downstream molecules. Several studies have shown the increased role of infection factors in pathogenesis of B cell chronic lymphocytic leukemia (B-CLL). This prompted us to test whether there is a correlation between MyD88-TIRAP dynamics before and after inflammatory stimuli. We determined the mRNA and protein expression of TIRAP and MyD88 in CD5(+)CD19(+) B-CLL cells and in a subpopulation of normal B CD19(+) lymphocytes. Additionally we determined the influence of lipopolysaccharide Escherichia coli - TLR4-ligand (LPS) and Staphylococcus aureus strain Cowan I - TLR2-ligand (SAC) on TIR-domain-containing adaptor protein, also called MyD88 adaptor-like (TIRAP) and myeloid differentiation primary response protein 88 (MyD88) expression. We have found that the mRNA and protein expression of TIRAP and MyD88 in B-CLL lymphocytes is lower compared with that in normal B lymphocytes. LPS and SAC stimulation in normal lymphocytes significantly altered neither TIRAP nor MyD88 mRNA expression, whereas TIRAP protein level substantially decreased after TLR agonist treatment. We did not observe any changes in MyD88 protein level after B lymphocyte stimulation. There was a significant increase in TIRAP mRNA expression after LPS and SAC stimulation of B-CLL cells. MyD88 mRNA expression levels in B-CLL lymphocytes slightly decreased upon treatment with either stimulator. Stimulation with TLR agonists did not cause changes in TIRAP and MyD88 expression at the protein level in B-CLL lymphocytes. The results of our study suggest that there may exist a, yet unknown, defect of TIRAP and MyD88 proteins in B-CLL lymphocytes.
Subject(s)
Gene Expression Regulation, Leukemic , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Membrane Glycoproteins/genetics , Myeloid Differentiation Factor 88/genetics , Receptors, Interleukin-1/genetics , Aged , Antigens, CD/metabolism , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , Cells, Cultured , Female , Humans , Immunophenotyping , Leukemia, Lymphocytic, Chronic, B-Cell/metabolism , Lipopolysaccharides/immunology , Male , Membrane Glycoproteins/metabolism , Middle Aged , Myeloid Differentiation Factor 88/metabolism , Neoplasm Staging , RNA, Messenger/genetics , RNA, Messenger/metabolism , Receptors, Interleukin-1/metabolismABSTRACT
B-cell receptor (BCR) and Toll-like receptor (TLR) stimulation and integration with signals from the pathogen or immune cells and their products determine the B-cell antibody response. Low expression of BCR is the hallmark of B lymphocytes in CLL, however little is known about the expression and function of TLR in B-CLL. We studied TLR2, TLR4, IL-6 and mIL-6Rα expression on mRNA and protein level in CD19(+) subpopulation of normal lymphocytes and the CD19(+)CD5(+) subpopulation from B-CLL. Experiments were performed on unstimulated and stimulated lymphocytes [Staphylococcus aureus Cowan I (SAC) and lipopolysaccharide (LPS) from Escherichia coli - TLR2- and TLR4-specific agonists, respectively]. We showed undetectable or low IL-6 expression, which seems to be specific for B-CLL lymphocytes. Induction of TLR4 mRNA upon LPS stimulation affected the expression of IL-6, but not of mIL-6Rα. Increased expression of TLR2 (MFI) after LPS and SAC stimulation did not correlate with mIL-6Rα receptor expression. B-CLL CD19(+)CD5(+) lymphocytes showed a significant increase in TLR2 expression at the protein level after stimulation with SAC and LPS compared to normal CD19(+) lymphocytes. TLR2 may influence the behaviour of the malignant clone in B-CLL.
Subject(s)
Gene Expression Regulation, Leukemic/immunology , Leukemia, Lymphocytic, Chronic, B-Cell/immunology , Toll-Like Receptor 2/immunology , Aged , Aged, 80 and over , Female , Gene Expression Regulation, Leukemic/drug effects , Humans , Interleukin-6/biosynthesis , Interleukin-6/immunology , Leukemia, Lymphocytic, Chronic, B-Cell/metabolism , Lipopolysaccharides/pharmacology , Male , Middle Aged , Receptors, Antigen, B-Cell/biosynthesis , Receptors, Antigen, B-Cell/immunology , Staphylococcus aureus/immunology , Toll-Like Receptor 2/biosynthesis , Toll-Like Receptor 4/biosynthesis , Toll-Like Receptor 4/immunologyABSTRACT
BACKGROUND: Current hypertension guidelines recommend using two antihypertensive agents when blood pressure (BP) control is not achieved with one single agent. OBJECTIVE: This study was designed to assess the antihypertensive benefit of the olmesartan medoxomil 40 mg/hydrochlorothiazide (HCTZ) 12.5 mg combination versus olmesartan medoxomil 40 mg monotherapy in patients with moderate to severe hypertension. METHODS: This was a randomized, double-blind, parallel-group, up-titration, multicentre, multinational, phase III study. Following a 2-week single-blind placebo run-in phase, 846 hypertensive patients with mean seated systolic BP (SeSBP) of 160-200 mmHg and mean seated diastolic BP (SeDBP) of 100-120 mmHg were randomized (1 : 2 ratio) to receive double-blind treatment with olmesartan medoxomil 40 mg or olmesartan medoxomil 40 mg/HCTZ 12.5 mg for 8 weeks (phase A). At week 8, patients not reaching BP goal (<140/90 mmHg; <130/80 mmHg in patients with diabetes mellitus) were up-titrated from olmesartan medoxomil 40 mg to olmesartan medoxomil 40 mg/HCTZ 12.5 mg or from olmesartan medoxomil 40 mg/HCTZ 12.5 mg to olmesartan medoxomil 40 mg/HCTZ 25 mg for an additional 8 weeks (phase B). Patients on goal continued their initial treatment. The primary efficacy parameter was the change in mean SeDBP during phase A. RESULTS: Olmesartan medoxomil 40 mg/HCTZ 12.5 mg reduced mean SeDBP significantly more (-18.9 mmHg) than olmesartan medoxomil 40 mg (-15.8 mmHg) after 8 weeks of double-blind treatment (difference: -3.1 mmHg, p < 0.0001). Olmesartan medoxomil 40 mg/HCTZ 12.5 mg also reduced mean SeSBP significantly more than olmesartan medoxomil 40 mg (-5.4 mmHg, p < 0.0001). As a result, BP goal rates at week 8 were significantly higher with olmesartan medoxomil 40 mg/HCTZ 12.5 mg than with olmesartan medoxomil 40 mg (58.5% vs 44.3%; odds ratio 1.88; 95% CI 1.32, 2.54). During phase B, mean BP reductions were greater in patients up-titrated from olmesartan medoxomil 40 mg to olmesartan medoxomil 40 mg/HCTZ 12.5 mg than in those continuing on olmesartan medoxomil 40 mg (SeDBP: -9.3 mmHg vs -0.5 mmHg; SeSBP: -12.4 mmHg vs -0.5 mmHg). Similarly, mean BP reductions were greater in patients up-titrated from olmesartan medoxomil 40 mg/HCTZ 12.5 mg to olmesartan medoxomil 40 mg/HCTZ 25 mg than in those continuing on olmesartan medoxomil 40 mg/HCTZ 12.5 mg (SeDBP: -8.0 mmHg vs -0.3 mmHg; SeSBP: -12.1 mmHg vs -0.4 mmHg). In patients not on goal at week 8, addition of HCTZ 12.5 mg to olmesartan medoxomil 40 mg or up-titration from olmesartan medoxomil 40 mg/HCTZ 12.5 mg to olmesartan medoxomil 40 mg/HCTZ 25 mg brought additional patients to goal at week 16 (38.8% vs 36.9%). All treatments were well tolerated. CONCLUSION: The olmesartan medoxomil 40 mg/HCTZ 12.5 mg combination is superior to olmesartan medoxomil 40 mg monotherapy in reducing SeDBP and SeSBP and increasing BP goal rates after 8 weeks. Patients not on goal at week 8 with olmesartan medoxomil 40 mg or olmesartan medoxomil 40 mg/HCTZ 12.5 mg benefited from adding HCTZ 12.5 mg or up-titrating to olmesartan medoxomil 40 mg/HCTZ 25 mg, respectively, confirming that up-titration is a clinically meaningful way to improve BP control. [ TRIAL REGISTRATION NUMBER: NCT00441350 (ClinicalTrials.gov Identifier)].