Immune-pineal axis activation is part of the assembly of immune responses. Proinflammatory cytokines inhibit the pineal synthesis of melatonin while inducing it in macrophages by mechanisms dependent on nuclear factor-κB (NF-κB) activation. Cytokines activating the Janus kinase/signal transducer and activator of transcription (STAT) pathways, such as interferon-gamma (IFN-γ) and interleukin-10 (IL-10), modulate melatonin synthesis in the pineal, bone marrow (BM), and spleen.
View Article and Find Full Text PDFChronic inflammatory diseases are triggered by causal stimuli that might occur long before the appearance of the symptoms. Increasing evidence suggests that these stimuli are necessary but not always sufficient to induce the diseases. The murine model of type II collagen emulsified in Freund's incomplete adjuvant (collagen-induced arthritis) to induce rheumatoid arthritis (RA) follows this pattern as some animals do not develop the chronically inflamed phenotype.
View Article and Find Full Text PDFPathogen-associated molecular patterns modulate melatonin (MEL) production in the pineal and extra-pineal sites and corticosterone (CORT) synthesis in the adrenal/interrenal and other tissues. Both MEL and CORT play essential and complex immunomodulatory roles, controlling the inflammatory response. Given that most of what we know about these interactions is derived from mammalian studies, discovering how MEL and CORT are modulated following an immune challenge in anurans would increase understanding of how conserved these immune-endocrine interactions are in vertebrates.
View Article and Find Full Text PDFDaily oscillation of the immune system follows the central biological clock outputs control such as melatonin produced by the pineal gland. Despite the literature showing that melatonin is also synthesized by macrophages and T lymphocytes, no information is available regarding the temporal profile of the melatonergic system of immune cells and organs in steady-state. Here, the expression of the enzymes arylalkylamine-N-acetyltransferase (AA-NAT), its phosphorylated form (P-AA-NAT) and acetylserotonin-O-methyltransferase (ASMT) were evaluated in phagocytes and T cells of the bone marrow (BM) and spleen.
View Article and Find Full Text PDFSepsis constitutes one of the major causes of death in ICUs. In sepsis induced by gram-negative, although lipopolysaccharide (LPS) initially induces an exacerbated secretion of proinflammatory cytokines leading to endotoxic shock and death resembling a septic shock, it is also capable of inducing refractoriness to subsequent challenge with LPS, a state known as endotoxin tolerance, which is considered the initial step of the immunosuppression found in septic patients. As we previously demonstrated the importance of glucocorticoids in endotoxin tolerance, the aim of this study was to evaluate the contribution of Interleukin-10 (IL-10) both in the endotoxic shock and in the development of the tolerance and its relationship with glucocorticoids.
View Article and Find Full Text PDFThe ability of (Mtb) to persist in its human host relies on numerous immune evasion strategies, such as the deregulation of the lipid metabolism leading to the formation of foamy macrophages (FM). Yet, the specific host factors leading to the foamy phenotype of Mtb-infected macrophages remain unknown. Herein, we aimed to address whether host cytokines contribute to FM formation in the context of Mtb infection.
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