Nutritional lipids supplied during critical illness have been shown to modulate the host response to inflammation. In particular, inclusion of omega-3 fatty acids seems to have beneficial effects on cellular immunity and helps to maintain the balance between pro- and anti-inflammatory cytokines thereby preventing hyperinflammatory complications. In addition to improvements in the profile of lipid mediators generated, omega-3 fatty acids act as activating ligands of peroxisome proliferator-activated receptors and directly inhibit nuclear factor kappaB mediated proinflammatory signaling. We present an overview on the alterations in the metabolism of serum lipoproteins during sepsis and present data from clinical studies and discuss the significance of nutritional lipids and their role in immunomodulation with special emphasis on omega-3 fatty acids.

(WK) S U M M A R Y The endothelin (ET) receptor system is markedly involved in the regulation of renal function under both physiological and pathophysiological conditions. The present study determined the detailed cellular localization of both ET receptor subtypes, ET A and ET B , in the vascular and tubular system of the rat kidney by immunofluorescence microscopy. In the vascular system we observed both ET A and ET B receptors in the media of interlobular arteries and afferent and efferent arterioles. In interlobar and arcuate arteries, only ET A receptors were present on vascular smooth muscle cells. ET B receptor immunoreactivity was sparse on endothelial cells of renal arteries, whereas there was strong labeling of peritubular and glomerular capillaries as well as vasa recta endothelium. ET A receptors were evident on glomerular mesangial cells and pericytes of descending vasa recta bundles. In the renal tubular system, ET B receptors were located in epithelial cells of proximal tubules and inner medullary collecting ducts, whereas ET A receptors were found in distal tubules and cortical collecting ducts. Distribution of ET A and ET B receptors in the vascular and tubular system of the rat kidney reported in the present study supports the concept that both ET receptor subtypes cooperate in mediating renal cortical vasoconstriction but exert differential and partially antagonistic effects on renal medullary function.

Omega-3 fatty acids (omega3-FA) were shown to attenuate growth and induce apoptosis in a variety of human cancer cell lines derived from colonic, pancreatic, prostate, and breast cancer. In addition, recent findings indicate that omega3-FA act synergistically with chemotherapeutic agents and may also be used to enhance tumour radiosensitivity. The mechanisms underlying the anti-tumour effects of omega3-FA are complex. Incorporation of omega3-FA in biological membranes alters the profile of lipid mediators generated during inflammatory reactions. Furthermore, omega3-FA act as ligands of nuclear peroxisome proliferator-activated receptors that attenuate transcription of NF-kappaB-dependent genes. Thereby, the cyclooxygenase-2/prostaglandin E(2)-dependent production of pro-angiogenic vascular endothelial growth factor and levels of anti-apoptotic bcl-2 and bcl-X(L) are decreased. Eicosanoid-independent pro-apoptotic pathways include enhanced lipid peroxidation, modulation of mitochondrial calcium homeostasis and enhanced production of reactive oxygen species as well as activation of p53. This review article will give a comprehensive overview over the pleiotropic actions of omega3-FA and will discuss the potential of omega3-FA and derivatives like conjugated eicosapentaenoic acid as important nutritional adjuvant therapeutics in the management of various human cancer diseases and the impact of nutritional omega-3 FA on cancer prevention.

Summary Quadriceps weakness seems to be a hallmark in adult persons with severe haemophilia (PWH). The purpose of this study was to compare PWH and non‐haemophilic controls in different age stages with reference to joint status and quadriceps strength. Further aims were to examine the extent of strength‐specific inter‐extremity‐difference (IED) and the prevalence of abnormal IED (AIED). A total of 106 adults with severe haemophilia (H) and 80 controls (C) had undergone an orthopaedic examination for classification of knee and ankle status using the WFH score. Quadriceps strength was evaluated unilaterally as well as bilaterally with a knee extensor device. Each group was divided into four age‐related subgroups (HA/CA: 18–29, HB/CB: 30–39, HC/CC: 40–49, HD/CD: 50–70; in years). H presented a worse knee and ankle status than C indicated by higher WFH scores (P < 0.01). Regarding the age‐matched subgroups only HB showed higher knee scores than CB (P < 0.05). The ankles were clinically more affected in HB‐HD compared with those in age‐matched controls (P < 0.05). H showed lower quadriceps strength than C (P < 0.05). In addition, all subgroups of H presented lower strength (HA: 10–17, HB: 19–23, HC: 35–36, HD: 53–61; in%, P < 0.05). IED was higher in H than in C [H: 12.0 (5.3/32.2) vs. C: 7.1 (2.9/10.9); Median (quartiles) in%, P < 0.001] and increased with age in H. We discovered an AIED in 35% of H. These findings highlight the importance for the early implementation of preventive and rehabilitative muscle training programmes in the comprehensive treatment of PWH.

In this feasibility study, Fourier domain optical coherence tomography (FDOCT) is used for visualizing the 3-D structure of fixated lung parenchyma and to capture real-time cross sectional images of the subpleural alveolar mechanics in a ventilated and perfused isolated rabbit lung. The compact and modular setup of the FDOCT system allows us to image the first 500 microm of subpleural lung parenchyma with a 3-D resolution of 16 x 16 x 8 microm (in air). During mechanical ventilation, real-time cross sectional FDOCT images visualize the inflation and deflation of alveoli and alveolar sacks (acini) in successive images of end-inspiratory and end-expiratory phase. The FDOCT imaging shows the relation of local alveolar mechanics to the setting of tidal volume (VT), peak airway pressure, and positive end-expiratory pressure (PEEP). Application of PEEP leads to persistent recruitment of alveoli and acini in the end-expiratory phase, compared to ventilation without PEEP where alveolar collapse and reinflation are observed. The imaging of alveolar mechanics by FDOCT will help to determine the amount of mechanical stress put on the alveolar walls during tidal ventilation, which is a key factor in understanding the development of ventilator induced lung injury (VILI).

Adenosine A1- and A2-receptor agonists reduced LPS-induced vasoconstriction and oedema formation by maintenance of tissue energy content. Thus, adenosine receptor stimulation, in particular of the A2 receptor, might be beneficial during acute lung injury.

Retinal ganglion cell degeneration is supposed to be mediated by reactive oxygen species (ROS) and advanced glycation end products (AGEs). The alpha2‐adrenergic agonist, 5‐bromo‐N‐(4,5‐dihydro‐1H‐imidazol‐2‐yl)‐6‐quinoxalinamine (brimonidine; UK‐14,304), is said to exert a neuroprotective effect. To investigate these mechanisms in detail, we exposed rat whole mounts to glyoxal or H2O2 and treated them with either UK‐14,304 alone or additionally with the phosphatidylinositide 3 kinase (PI3) kinase inhibitor, 2‐(4‐Morpholinyl)‐8‐phenyl‐4H‐1‐benzopyran‐4‐one (Ly 294002). The accumulation of Nε‐[carboxymethyl] lysine (CML) was assessed immunohistochemically and changes in intracellular pH (pHi), mitochondrial transmembrane potential (MTMP) and ROS production in cell bodies of multipolar ganglion cell layer were studied by intravital fluorescence microscopy and confocal laser scanning microscopy. Ultrastructural changes in mitochondria of multipolar ganglion cell layer cell bodies were determined by transmission electron microscopy. We found that glyoxal and H2O2 increased accumulation of CML‐modified proteins and ROS production and decreased pHi and MTMP in cell bodies of multipolar ganglion cell layer. UK‐14,304 could prevent production of ROS, accumulation of CML‐modified proteins, ameliorate acidification, preserve MTMP and attenuate ultrastructural damages of ganglion cell mitochondria. Ly 294002 reversed the UK‐14,304‐mediated attenuation of CML and ROS production. We conclude that the protective effects of UK‐14,304 seem partly to be mediated by PI3 kinase‐dependent pathways.

Pulmonary fibrosis is characterized by excessive extracellular matrix deposition with concomitant loss of gas exchange units, and endothelin-1 (ET-1) has been implicated in its pathogenesis. Increased levels of ET-1 from tissues and bronchoalveolar lavage have been reported in patients with pulmonary fibrosis and in animal models after intratracheal bleomycin. We characterized the cellular distribution of alveolar ET receptors by immunohistochemistry in bleomycin-induced pulmonary fibrosis in the rat and determined the regulation by bleomycin of ET receptor mRNA expression in isolated alveolar macrophages and rat lung fibroblasts. We found significant increases in the numbers of fibroblasts and macrophages at day 7 compared to day 28 and control animals. ET(B) receptor immunoreactivity was observed on fibroblasts and invading monocytes. Isolated fibroblasts expressed both ET(A) and ET(B) receptor mRNA, and ET(A) receptor mRNA was upregulated by bleomycin. Isolated resident alveolar macrophages expressed neither ET(A) nor ET(B) receptor mRNA which were also not induced by bleomycin. We conclude that, while ET(B) receptor stimulation of fibroblasts and monocytes recruited during bleomycin-induced lung injury exerts antagonistic effects on fibroblast collagen synthesis, the observed increase in the number of fibroblasts in vivo and upregulation of fibroblast ET(A) receptor mRNA by bleomycin in vitro point to a predominance of the profibrotic effects of ET receptor engagement.