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Biology subjects

Assis, P. A.

Publications and source records attributed to Assis, P. A..

2 recordsLinked to original sources

Reprogramming of host energy metabolism mediated by the TNF-iNOS-HIF-1alpha axis plays a key role in host resistance to Plasmodium infection

TNF has a dual effect in Plasmodium infection, bolstering the hosts immune defense while also inducing sickness behavior. Here, we confirm that TNF signaling hampers physical activity, food intake, and energy expenditure while enhancing glucose uptake by the liver and spleen as well as controlling parasitemia in P. chabaudi (Pc)-infected mice. We also report that TNF is required for expression of inducible nitric oxide synthase (iNOS), stabilization of HIF-1, expression of glucose transporter GLUT1 and enhanced glycolysis in monocytic cells from Pc-infected mice. Importantly, Pc-infected iNOS-/-, TNFR{Delta}Lyz2 and HIF-1{Delta}Lyz2 mice show impaired release of TNF and glycolysis in monocytes, along with increased parasitemia and disease tolerance. Altogether, our results indicate that TNF-iNOS-HIF-1-induced glycolysis in monocytes plays a critical role in host defense and sickness behavior in Pc-infected mice. TeaseThe role of host energy metabolism and glycolysis in monocytes as determinant of host resistance to Plasmodium infection and tolerance to disease.

immunology↗

CNBP controls c-Rel dependent IL-12 β gene transcription and Th1 immunity

An inducible program of inflammatory gene expression is a hallmark of antimicrobial defenses. Herein, we identified Cellular nucleic acid binding protein (Cnbp) as a specific regulator of interleukin-12{beta} gene transcription and Th1 immunity. Cnbp resides in the cytosol of macrophages and translocates to the nucleus in response to a broad range of microbial ligands. Cnbp-deficient macrophages had a selective impairment in their ability to induce IL12{beta} gene transcription. Cnbp interacted with c-Rel, an NF{kappa}B/Rel family member that controls IL12{beta} gene transcription. c-Rel nuclear translocation and DNA binding activity were dependent on Cnbp. Furthermore, Cnbp itself bound the IL12{beta} promoter. Lastly, Cnbp-deficient mice were more susceptible to acute toxoplasmosis associated with reduced production of IL12{beta}, as well as a reduced Th1 cell IFN{gamma} response essential to control parasite replication. Collectively, these findings identify Cnbp as a key regulator of c-Rel dependent IL12{beta} gene transcription and Th1 immunity.

immunology↗