Benznidazole Anti-Inflammatory Effects in Murine Cardiomyocytes and Macrophages Are Mediated by Class I PI3Kδ

Abstract

Benznidazole (Bzl), the drug of choice in many countries for the treatment of Chagas disease, leads to parasite clearance in the early stages of infection and contributes to immunomodulation. In addition to its parasiticidal effect, Bzl inhibits the NF-κB pathway. In this regard, we have previously described that this occurs through IL-10/STAT3/SOCS3 pathway. PI3K pathway is involved in the regulation of the immune system by inhibiting NF-κB pathway through STAT3. In this work, the participation of PI3K in the immunomodulatory effects of Bzl in cardiac and immune cells, the main targets of Chagas disease, was further studied. For that, we use a murine primary cardiomyocyte culture and a monocyte/macrophage cell line (RAW 264.7), stimulated with LPS in presence of LY294002, an inhibitor of PI3K. Under these conditions, Bzl could neither increase SOCS3 expression nor inhibit the NOS2 mRNA expression and the release of NOx, both in cardiomyocytes and macrophages. Macrophages are crucial in the development of Chronic Chagas Cardiomyopathy. Thus, to deepen our understanding of how Bzl acts, the expression profile of M1-M2 macrophage markers was evaluated. Bzl inhibited the release of NOx (M1 marker) and increased the expression of Arginase I (M2 marker) and a negative correlation was found between them. Besides, LPS increased the expression of pro-inflammatory cytokines. Bzl treatment not only inhibited this effect but also increased the expression of typical M2-macrophage markers like Mannose Receptor, TGF-β, and VEGF-A. Moreover, Bzl increased the expression of PPAR-γ and PPAR-α, known as key regulators of macrophage polarization. PI3K directly regulates M1-to-M2 macrophage polarization. Since p110δ, catalytic subunit of PI3Kδ, is highly expressed in immune cells, experiments were carried out in presence of CAL-101, a specific inhibitor of this subunit. Under this condition, Bzl could neither increase SOCS3 expression nor inhibit NF-κB pathway. Moreover, Bzl not only failed to inhibit the expression of pro-inflammatory cytokines (M1 markers) but also could not increase M2 markers. Taken together these results demonstrate, for the first time, that the anti-inflammatory effect of Bzl depends on PI3K activity in a cell line of murine macrophages and in primary culture of neonatal cardiomyocytes. Furthermore, Bzl-mediated increase expression of M2-macrophage markers involves the participation of the p110δ catalytic subunit of PI3Kδ.

Benznidazole-Loaded Polymeric Nanoparticles for Oral Chemotherapeutic Treatment of Chagas Disease

“…During the acute phase of CD, there is an intense inflammatory process in the vertebrate host’s body. Studies indicate that, in T. cruzi infection, there is an increase in NO production, which aims to contain the parasite [ 93 , 94 ]. However, excessive amounts of NO can have undesirable effects due to its pro-inflammatory effect, even though it is also responsible for the destruction of circulating forms of the parasite [ 95 ].…”

Degenerated nucleus pulposus cells derived exosome carrying miR-27a-3p aggravates intervertebral disc degeneration by inducing M1 polarization of macrophages

“…4 C). Studies have shown the essential role of PPARγ/NFκB/PI3K/AKT signaling pathway in the regulation process of macrophages polarization [ 15 , 16 ]. Therefore, plasmid or siRNA was used to regulate PPARγ gene expression in M0 macrophages.…”

Fenofibrate Induces a Resolving Profile in Heart Macrophage Subsets and Attenuates Acute Chagas Myocarditis

“…Numerous studies support the significance of key components in the inflammatory and fibrotic response, contributing to the initiation, progression, and maintenance of cardiac symptoms in this infectious pathology. ,,,− In this regard, our group has been dedicated to investigate the relevance of anti-inflammatory treatments with the attempt to ameliorate the inflammatory consequences of cardiac damage associated with Chagas disease. ,− ,,,− Besides, in recent years several authors have proposed diverse pharmacological agents as potential immunotherapy for this pathology . In this context, and delving further into the study of fenofibrate properties, here, we demonstrate the capability of this synthetic PPARα ligand to inhibit not only the cardiac inflammatory infiltrate but also the cardiac expression of iNOS, TNFα, IL-6, and CCR2 in the early stage of the disease.…”