Differential Regulation of L-Arginine Metabolism through NOS2 and Arginases during Infection with .

L-arginine metabolism through arginases and inducible nitric oxide synthase (NOS2) constitutes a fundamental axis for the resolution or progression of Chagas disease. Infection with can cause a wide spectrum of disease, ranging from acute forms contained by the host immune response to chronic ones, such as the chronic chagasic cardiomyopathy. Here, we analyzed, in an in vitro model, the ability of two isolates, with different degrees of virulence, to regulate the metabolism of L-arginine through arginase 1 (Arg-1) and NOS2 in macrophages and through arginase 2 (Arg-2) and NOS2 in cardiomyocytes.

Artemisinin: An Anti-Leishmania Drug that Targets the Leishmania Parasite and Activates Apoptosis of Infected Cells.

Leishmaniasis is a relevant disease worldwide due to its presence in many countries and an estimated prevalence of 10 million people. The causative agent of this disease is the obligate intracellular parasite Leishmania which can infect different cell types. Part of its success depends on its ability to evade host defense mechanisms such as apoptosis.

Human Dendritic Cell Maturation Is Modulated by through Akt Signaling Pathway.

Dendritic cells (DC) along with macrophages are the main host cells of the intracellular parasite . DC traverse a process of maturation, passing through an immature state with phagocytic ability to a mature one where they can modulate the immune response through the secretion of cytokines. Several studies have demonstrated that inhibits DC maturation.

Apoptosis and its pathways as targets for intracellular pathogens to persist in cells.

Apoptosis is a finely programmed process of cell death in which cells silently dismantle and actively participate in several operations such as immune response, differentiation, and cell growth. It can be initiated by three main pathways: the extrinsic, the perforin granzyme, and the intrinsic that culminate in the activation of several proteins in charge of tearing down the cell. On the other hand, apoptosis represents an ordeal for pathogens that live inside cells and maintain a strong dependency with them; thus, they have evolved multiple strategies to manipulate host cell apoptosis on their behalf.

Involvement of Akt and the antiapoptotic protein Bcl-xL in the inhibition of apoptosis of dendritic cells by Leishmania mexicana.

The intracellular parasite Leishmania mexicana inhibits camptothecin (CPT)-induced apoptosis of monocyte-derived dendritic cells (moDC) through the down-regulation of p38 and JNK phosphorylation, while the kinase Akt is maintained active for 24 h. In addition, the infection of moDC with L. mexicana promastigotes increases the protein presence of the antiapoptotic protein Bcl-xL.