Concentrations of Hepatocyte Growth Factor, Basic Fibroblast Growth Factor, and Vascular Endothelial Growth Factor in Pericardial Fluid and Plasma

Accumulation of Inflammatory Mediators in the Normal Pericardial Fluid

There is paucity of studies that focus on the composition of pericardial fluid under resting conditions. The purpose of this study is to determine the levels of inflammatory mediators in pericardial fluid and their correlation with plasma levels in patients undergoing elective cardiac surgery. We conducted a prospective cohort study on candidates for elective aortic valve replacement surgery. Pericardial fluid and peripheral venous blood samples were collected after opening the pericardium. Levels of interleukin 1α (IL-1α); interleukin 1β (IL-1β); interleukin 2 (IL-2) interleukin 4 (IL-4); interleukin 6 (IL-6); interleukin 8 (IL8); interleukin 10 (IL10); tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), vascular endothelial growth factor (VEGF), monocyte chemotactic protein-1 (MCP-1) epidermal growth factor (EGF), soluble E-selectin, L-selectin, P-selectin, intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) were determined in both pericardial fluid and serum samples. A total of 45 patients with a mean age of 74 years were included of which 66% were males. Serum levels of all study mediators were within normal limits. Serum and pericardial levels of IL-1 α, IL-1 β, IL-2, IL-4, and IL-10 were similar. Levels of VEGF, EGF, VCAM-2, ICAM 1, E-selectin, P-selectin, and L-selectin were significantly lower in pericardial fluid than in serum. However, levels of IL-6, IL-8, TNF-α, IFN-γ, MCP-1, and MCP-1 were significantly higher in the pericardial fluid than in serum. Under normal conditions, the pattern of distribution of different inflammatory mediators in the pericardial fluid does not reflect serum levels. This may either reflect the condition of the underlying myocardium and epicardial fat or the activity of the mesothelial and mononuclear cells present in pericardial fluid.

Incorporation of FGF-2 into Pharmaceutical Grade Fucoidan/Chitosan Polyelectrolyte Multilayers

Biopolymer polyelectrolyte multilayers are a commonly studied soft matter system for wound healing applications due to the biocompatibility and beneficial properties of naturally occurring polyelectrolytes. In this work, a popular biopolymer, chitosan, was combined with the lesser known polysaccharide, fucoidan, to create a multilayer film capable of sequestering growth factor for later release. Fucoidan has been shown to act as a heparin-mimic due to similarities in the structure of the two molecules, however, the binding of fibroblast growth factor-2 to fucoidan has not been demonstrated in a multilayer system. This study assesses the ability of fucoidan to bind fibroblast growth factor-2 within a fucoidan/chitosan polyelectrolyte multilayer structure using attenuated total internal reflectance infrared spectroscopy and quartz crystal microbalance with dissipation monitoring. The fibroblast growth factor-2 was sequestered into the polyelectrolyte multilayer as a cationic layer in the uppermost layers of the film structure. In addition, the diffusion of fibroblast growth factor-2 into the multilayer has been assessed.

Effect of Co-culturing Fibroblasts in Human Skeletal Muscle Cell Sheet on Angiogenic Cytokine Balance and Angiogenesis

Skeletal muscle comprises a heterogeneous population of myoblasts and fibroblasts. Autologous skeletal muscle myoblasts are transplanted to patients with ischemia to promote cardiac regeneration. In damaged hearts, various cytokines secreted from the skeletal muscle myoblasts promote angiogenesis and consequently the recovery of cardiac functions. However, the effect of skeletal muscle fibroblasts co-cultured with skeletal muscle myoblasts on angiogenic cytokine production and angiogenesis has not been fully understood. To investigate these effects, production of vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) was measured using the culture medium of monolayers prepared from various cell densities (mono-culture) and proportions (co-culture) of human skeletal muscle myoblasts (HSMMs) and human skeletal muscle fibroblasts (HSMFs). HSMM and HSMF mono-cultures produced VEGF, whereas HSMF mono-culture produced HGF. The VEGF productivity observed in a monolayer comprising low proportion of HSMFs was two-fold greater than that of HSMM and HSMF mono-cultures. The production of VEGF in HSMMs but not in HSMFs was directly proportional to the cell density. VEGF productivity in non-confluent cells with low cell-to-cell contact was higher than that in confluent cells with high cell-to-cell contact. The dynamic migration of cells in a monolayer was examined to analyze the effect of HSMFs on myoblast-to-myoblast contact. The random and rapid migration of HSMFs affected the directional migration of surrounding HSMMs, which disrupted the myoblast alignment. The effect of heterogeneous populations of skeletal muscle cells on angiogenesis was evaluated using human umbilical vein endothelial cells (HUVECs) incubated with fabricated multilayer HSMM sheets comprising various proportions of HSMFs. Co-culturing HSMFs in HSMM sheet at suitable ratio (30 or 40%) enhances endothelial network formation. These findings indicate the role of HSMFs in maintaining cytokine balance and consequently promoting angiogenesis in the skeletal muscle cell sheets. This approach can be used to improve transplantation efficiency of engineered tissues.

The roles of natriuretic peptides in pericardial fluid in patients with heart failure

BACKGROUND

It is well known that the plasma concentrations of atrial and brain natriuretic peptides, as cardiac hormones, are elevated in heart failure.

HYPOTHESIS

Pericardial fluid in patients with various heart diseases contains both natriuretic peptides that are released into the pericardial fluid. However, it is unknown whether these peptides reflect cardiac function in patients with various heart diseases, more than both the peptides in blood.

METHODS

Plasma and pericardial fluid samples were obtained from 22 patients undergoing cardiac surgery for the measurement of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) levels in plasma and pericardial fluid.

RESULTS

The ANP levels in pericardial fluid were higher in patients with impaired left ventricular systolic function (ejection fraction<50% versus>or=50%; 77.0+/-4.9 versus 14.0+/-50.9, p=0.017), but not BNP.However, BNP levels in pericardial fluid were significantly higher in patients with left ventricle dilatation (left ventricular diastolic dimension<or=54 mm versus>54 mm; 130.3+/-68.9: 709.7+/-324.7, p=0.0168). Moreover, BNP levels in pericardial fluid were significantly higher in Grade III than Grade II and I (Grade I: echo-free space<5 mm, Grade II: 5-10 mm, Grade III: >10 mm).

CONCLUSION

These results suggest that BNP levels in pericardial fluid served as more sensitive and accurate indicators of left ventricular diastolic dysfunction, and that increased BNP levels in pericardial fluid may have an important pathophysiologic role in heart failure as a cardiocyte-derived antifibrotic factor.