Reduction of circulating cholesterol and apolipoprotein levels during sepsis

Sepsis with multiple organ failure is frequently associated with a substantial decrease of cholesterol levels. This decrease of cholesterol is strongly associated with mortality suggesting a direct relation between inflammatory conditions and altered cholesterol homeostasis. The host response during sepsis is mediated by cytokines and growth factors, which are capable of influencing lipid metabolism. Conversely lipoproteins are also capable of modulating cytokine production during the inflammatory response. Therefore the decrease in circulating cholesterol levels seems to play a crucial role in the pathophysiology of sepsis. In this review the interaction between cytokines and lipid metabolism and its clinical consequences will be discussed

Mycobacteria counteract a TLR-mediated nitrosative defense mechanism in a zebrafish infection model.

Pulmonary tuberculosis (TB), caused by the intracellular bacterial pathogen Mycobacterium tuberculosis (Mtb), is a major world health problem. The production of reactive nitrogen species (RNS) is a potent cytostatic and cytotoxic defense mechanism against intracellular pathogens. Nevertheless, the protective role of RNS during Mtb infection remains controversial. Here we use an anti-nitrotyrosine antibody as a readout to study nitration output by the zebrafish host during early mycobacterial pathogenesis. We found that recognition of Mycobacterium marinum, a close relative of Mtb, was sufficient to induce a nitrosative defense mechanism in a manner dependent on MyD88, the central adaptor protein in Toll like receptor (TLR) mediated pathogen recognition. However, this host response was attenuated by mycobacteria via a virulence mechanism independent of the well-characterized RD1 virulence locus. Our results indicate a mechanism of pathogenic mycobacteria to circumvent host defense in vivo. Shifting the balance of host-pathogen interactions in favor of the host by targeting this virulence mechanism may help to alleviate the problem of infection with Mtb strains that are resistant to multiple drug treatments

BioMoon: a concept for a mission to advance space life sciences and astrobiology on the Moon

As humans advance their presence in space and seek to improve the quality of life on Earth, a variety of science questions in support of these two objectives can be answered using the Moon. In this paper, we present a concept for an integrated mission focused on answering fundamental and applied biological questions on the Moon: BioMoon. The mission was designed to investigate the effects of the lunar radiation, gravity, and regolith on biological systems ranging from biomolecules to systems with complex trophic interactions, spanning a range of model organisms. Using common analytical systems and data processing, BioMoon represents a systems-level integrated life sciences mission. It would provide fundamental insights into biological responses to the lunar environment, as well as applied knowledge for In-Situ Resource Utilisation (ISRU), closed-loop life support system development, planetary protection and human health care. The mission was conceived to test biotechnology and sensor technology for lunar and terrestrial application and provide education and outreach opportunities. Although BioMoon was considered in the context of the European Space Agency’s Argonaut (European Large Logistics Lander) concept, the mission design provides a template for any integrated life sciences experimental suite on the Moon and other celestial bodies, implemented either robotically or by human explorers