Trends in genomic analysis of the cardiovascular system

Strategies Developed to Induce, Direct, and Potentiate Bone Healing

Bone exhibits a great ability for endogenous self-healing. Nevertheless, impaired bone regeneration and healing is on the rise due to population aging, increasing incidence of bone trauma and the clinical need for the development of alternative options to autologous bone grafts. Current strategies, including several biomolecules, cellular therapies, biomaterials, and different permutations of these, are now developed to facilitate the vascularization and the engraftment of the constructs, to recreate ultimately a bone tissue with the same properties and characteristics of the native bone. In this review, we browse the existing strategies that are currently developed, using biomolecules, cells and biomaterials, to induce, direct and potentiate bone healing after injury and further discuss the biological processes associated with this repair.

Role of angiogenesis in bone repair

Bone vasculature plays a vital role in bone development, remodeling and homeostasis. New blood vessel formation is crucial during both primary bone development as well as fracture repair in adults. Both bone repair and bone remodeling involve the activation and complex interaction between angiogenic and osteogenic pathways. Interestingly studies have demonstrated that angiogenesis precedes the onset of osteogenesis. Indeed reduced or inadequate blood flow has been linked to impaired fracture healing and old age related low bone mass disorders such as osteoporosis. Similarly the slow penetration of host blood vessels in large engineered bone tissue grafts has been cited as one of the major hurdle still impeding current bone construction engineering strategies. This article reviews the current knowledge elaborating the importance of vascularization during bone healing and remodeling, and the current therapeutic strategies being adapted to promote and improve angiogenesis.

Low birth weight and markers of inflammation and endothelial activation in adulthood: the ARIC study

BACKGROUND

To investigate the hypothesis that intrauterine growth restriction might produce a longstanding pro-inflammatory tendency, we investigated the association of low birth weight with blood levels of markers of inflammation and endothelial activation in middle-aged adults.

METHODS

The ARIC Study enrolled subjects aged 45-64 years sampled from four U.S. communities. An inflammation/endothelial activation score from 0 to 6 was created, one point being given for each above-median value of white blood cell count, fibrinogen, von Willebrand factor and Factor VIII, and for each below-median value of albumin and activated partial thromboplastin time.

RESULTS

Of the 9809 individuals reporting birth weight and having all inflammation/endothelial markers and covariates, 349 (3.6%) reported low birth weight (LBW). The mean (standard deviation) score was 3.5 (1.5) for those with and 3.1 (1.6) for those without LBW (p<0.001). In robust poisson regression models adjusting for gender, ethnicity, age, study center, educational level, and current drinking and smoking status and amount, those with LBW were more likely to have a high score (> or =4 points) (RR=1.16, 95% CI: 1.05-1.29).

CONCLUSION

In the ARIC Study, LBW predicted greater inflammation and endothelial activation, as indicated by the higher score of blood markers, consistent with the hypothesis that early life events may result in a hyper-responsive innate immune system. Such a pro-inflammatory tendency could help explain the association of low birth weight with elements of the metabolic syndrome and ischemic heart disease.

Cardiovascular genomics: a current overview of in vivo and in vitro studies

The cardiovascular system is the first system that is developed in the embryo. The cardiovascular development is a complex process involving the coordination, differentiation, and interaction of distinct cell lineages to form the heart and the diverse array of arteries, veins, and capillaries required to supply oxygen and nutrients to all tissues. Embryonic stem cells have been proposed as an interesting model system to investigate molecular and cellular mechanisms involved in mammalian development. The present review is focused on extrinsic soluble factors, intrinsic transcription factors, receptors, signal transduction pathways, and genes regulating the development of cardiovascular system in vivo and in vitro. Special emphasis has been given to cardiovascular genomics including gene expression studies on the cardiovascular system under developmental and pathophysiological conditions.

Cardiovascular genomics

The ongoing explosion of genomic information is revolutionizing cardiovascular science. More complete genomic maps allow easier identification of genes that cause monogenic inherited diseases. In addition, analyses of variations in gene expression in cardiovascular diseases are revealing new potential candidate genes as well as novel biomarkers for many common, multifactorial diseases. While experiments are revealing new pathophysiologic pathways, these genomic studies are also generating enormous amounts of data. Even as we learn how to sift through mountains of genomic information, new technologies in proteomics are rapidly advancing and promise to provide additional critical tools for diagnosis and for identifying new therapies.

Gene expression profiling in hypertension research: a critical perspective

Recent advances in molecular biology and technology have made it possible to monitor the expression levels of virtually all genes simultaneously. As the tools for gene expression profiling have become more widely available, the number of investigators applying this technology in hypertension research, as in other fields of biomedical research, has grown rapidly. At the same time, numerous articles have been published that discuss the technical aspects of gene profiling and its promise for advancing research on the pathogenesis and treatment of multiple clinical disorders. However, much of the research carried out with gene expression profiling has been of a correlational or descriptive nature, and the true value of this technology is unclear. Despite the initial wave of enthusiasm for gene expression profiling, its actual utility for studying multifactorial disorders like hypertension remains to be established. In this review, we offer a critical perspective on the use of gene expression profiling in hypertension research and discuss some emerging strategies for taking this technology beyond the limits of correlational and descriptive studies.