Sirt-1 activity in PBMC from patients with spondyloarthritis

Histone methylation and acetylation in macrophages as a mechanism for regulation of inflammatory responses

Macrophages respond to noxious stimuli and contribute to inflammatory responses by eliminating pathogens or damaged tissue and maintaining homeostasis. Response to activation signals and maintenance of homeostasis require tight regulation of genes involved in macrophage activation and inactivation processes, as well as genes involved in determining their polarization state. Recent evidence has revealed that such regulation occurs through histone modifications that render inflammatory or polarizing gene promoters accessible to transcriptional complexes. Thus, inflammatory and anti-inflammatory genes are regulated by histone acetylation and methylation, determining their activation state. Herein, we review the current knowledge on the role of histone modifying enzymes (acetyltransferases, deacetylases, methyltransferases, and demethylases) in determining the responsiveness and M1 or M2 polarization of macrophages. The contribution of these enzymes in the development of inflammatory diseases is also presented.

Nutrition and chronic inflammatory rheumatic disease

Nutrition is a major environmental influence on human health. Epidemiological and interventional studies suggest a pathophysiological or therapeutic role, respectively, for nutrition in inflammatory rheumatic diseases (IRDs). Nevertheless, the associations between nutrition and IRDs are often weak and inconsistent, and the available clinical trials on nutrition are methodologically flawed. Experimental evidence is accumulating that micronutrients in the diet may influence intestinal and systemic immune responses via complex interactions involving the gut microbiota. Micronutrients may, therefore, contribute to the pathogenesis of inflammatory diseases. No interventions targeting these interactions for diagnostic, prophylactic, or therapeutic purposes have been developed to date. Moreover, the relevance to human disease of experimental results obtained in animals or in vitro is unclear. Novel high-throughput technologies (-omics) may prove useful for a systems biology approach to these results that takes the complexity of the interactions into account. Concomitant cohort studies combining clinical and laboratory data collected over time may provide new impetus to research into the connections between nutrition and IRDs.