Eating disorders: the current status of molecular genetic research

Anorexia nervosa (AN) and bulimia nervosa (BN) are complex disorders characterized by disordered eating behavior where the patient’s attitude towards weight and shape, as well as their perception of body shape, are disturbed. Formal genetic studies on twins and families suggested a substantial genetic influence for AN and BN. Candidate gene studies have initially focused on the serotonergic and other central neurotransmitter systems and on genes involved in body weight regulation. Hardly any of the positive findings achieved in these studies were unequivocally confirmed or substantiated in meta-analyses. This might be due to too small sample sizes and thus low power and/or the genes underlying eating disorders have not yet been analyzed. However, some studies that also used subphenotypes (e.g., restricting type of AN) led to more specific results; however, confirmation is as yet mostly lacking. Systematic genome-wide linkage scans based on families with at least two individuals with an eating disorder (AN or BN) revealed initial linkage regions on chromosomes 1, 3 and 4 (AN) and 10p (BN). Analyses on candidate genes in the chromosome 1 linkage region led to the (as yet unconfirmed) identification of certain variants associated with AN. Genome-wide association studies are under way and will presumably help to identify genes and pathways involved in these eating disorders. The elucidation of the molecular mechanisms underlying eating disorders might improve therapeutic approaches

The enigma of in vivo oxidative stress assessment: isoprostanes as an emerging target

Oxidative stress is believed to be one of the major factors behind several acute and chronic diseases, and may also be associated with ageing. Excess formation of free radicals in miscellaneous body environment may originate from endogenous response to cell injury, but also from exposure to a number of exogenous toxins. When the antioxidant defence system is overwhelmed, this leads to cell damage. However, the measurement of free radicals or their endproducts is tricky, since these compounds are reactive and short lived, and have diverse characteristics. Specific evidence for the involvement of free radicals in pathological situations has been difficult to obtain, partly owing to shortcomings in earlier described methods for the measurement of oxidative stress. Isoprostanes, which are prostaglandin-like bioactive compounds synthesized in vivo from oxidation of arachidonic acid, independently of cyclooxygenases, are involved in many human diseases, and their measurement therefore offers a way to assess oxidative stress. Elevated levels of F2-isoprostanes have also been seen in the normal human pregnancy, but their physiological role has not yet been defined. Large amounts of bioactive F2-isoprostanes are excreted in the urine in normal basal situations, with a wide interindividual variation. Their exact role in the regulation of normal physiological functions, however, needs to be explored further. Current understanding suggests that measurement of F2-isoprostanes in body fluids provides a reliable analytical tool to study oxidative stress-related diseases and experimental inflammatory conditions, and also in the evaluation of various dietary antioxidants, as well as drugs with radical-scavenging properties. However, assessment of isoprostanes in plasma or urine does not necessarily reflect any specific tissue damage, nor does it provide information on the oxidation of lipids other than arachidonic acid

LIFT bioprinting for the study of the immune response

Immunology is a transversal field that is governed by a complex network of genetic and signalling pathways subtending a network of interacting cells. Laser bioprinting is a powerful tool to study complex biological systems like the ones that govern the immune response. The high accuracy and non-destructive nature of LIFT (Laser Induced Forward Transfer) is applied to the study of cell-cell interaction. In particular, single cell laser bioprinting helps to understand the relationship between the cell and their local environment. In this context, mobility of the cells in a network, along with their situation and the gene products they interact with, plays an important role in the behaviour of the immune system. In this work, we use a laser induced forward transfer blister assisted (BALIFT) approach to assess these cell-cell interactions in vitro. This method helps to understand properly the role of a cell within a network to increase our knowledge of the immune system response. This work presents BALIFT bioprinting of single hematopoietic cells with high spatial resolution. In particular, NK cells (natural killer) and T-lymphocyte are printed in different laser conditions and specific patterns to study cell viability and cell-cell interaction. By means of this technique, we can place cellular components on a previously designed matrix, allow us to test the molecular interactions between lymphocytes and pathogens

LIFT bioprinting for the study of the immune response

Immunology is a transversal field that is governed by a complex network of genetic and signalling pathways subtending a network of interacting cells. Laser bioprinting is a powerful tool to study complex biological systems like the ones that govern the immune response. The high accuracy and non-destructive nature of LIFT (Laser Induced Forward Transfer) is applied to the study of cell-cell interaction. In particular, single cell laser bioprinting helps to understand the relationship between the cell and their local environment. In this context, mobility of the cells in a network, along with their situation and the gene products they interact with, plays an important role in the behaviour of the immune system. In this work, we use a laser induced forward transfer blister assisted (BALIFT) approach to assess these cell-cell interactions in vitro. This method helps to understand properly the role of a cell within a network to increase our knowledge of the immune system response. This work presents BALIFT bioprinting of single hematopoietic cells with high spatial resolution. In particular, NK cells (natural killer) and T-lymphocyte are printed in different laser conditions and specific patterns to study cell viability and cell-cell interaction. By means of this technique, we can place cellular components on a previously designed matrix, allow us to test the molecular interactions between lymphocytes and pathogens

Assessment of 2D geometries in immune systems responses using LIFT (Laser Induced Forward Transfer) as a high accuracy bioprinting technique

The immune system is a very complex system that comprises a network of genetic and signalling pathways subtending a network of interacting cells. The location of the cells in a network, along with the gene products they interact with, rules the behaviour of the immune system. In order to acquire a better understanding of these processes, laser assisted bio-printing techniques emerges as one of the promising approaches to organize cells with high spatial resolution in two and three-dimensional patterns to enable the study the geometry influence in the immune system interactions. In particular, laser assisted bio-printing techniques using sub-nanosecond laser sources have better characteristics for application in this field, mainly dueto its higher spatial resolution, cell viability percentage and process automation