Lívia Teixeira

Heart institute (InCor) · Laboratory of Vascular biology

Coronavirus disease 2019 (COVID-19) is currently a worldwide emergency caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). In observational clinical studies, statins have been identified as beneficial to hospitalized patients with COVID-19. However, experimental evidence of underlying statins protection against SARS-CoV-2 remain...

Severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) is an emergent pathogen responsible for the coronavirus disease 2019 (COVID-19). Since its emergence, the novel coronavirus has rapidly achieved pandemic proportions causing remarkably increased morbidity and mortality around the world. A hypercoagulability state has been reported as a ma...

Viruses are obligate intracellular parasites that make use of the host metabolic machineries to meet their biosynthetic needs. Thus, identifying the host pathways essential for the virus replication may lead to potential targets for therapeutic intervention. The mechanisms and pathways explored by SARS-CoV-2 to support its replication within host c...

Brazil has the second-highest COVID-19 death rate worldwide, and Rio de Janeiro is among the states with the highest rate in the country. Although vaccine coverage has been achieved, it is anticipated that COVID-19 will transition into an endemic disease. It is concerning that the molecular mechanisms underlying clinical evolution from mild to seve...

Brazil has the second highest COVID-19 death rate while Rio de Janeiro is among the states with the highest rate in the country. Although effective vaccines have been developed, it is anticipated that the ongoing COVID-19 pandemic will transition into an endemic state. Under this scenario, it is worrisome that the underlying molecular mechanisms as...

Accumulating evidence into the pathogenesis of COVID-19 highlight a hypercoagulability state with high risk of life-threatening thromboembolic complications. However, the mechanisms of hypercoagulability and their link to hyperinflammation remain poorly understood. Here we investigate functions and mechanisms of platelet activation and platelet-mon...

Infection by SARS‐CoV‐2 may elicit uncontrolled and damaging inflammatory responses. Thus, it is critical to identify compounds able to inhibit virus replication and thwart the inflammatory reaction. Here, we show that the plasma levels of the immunoregulatory neuropeptide VIP are elevated in patients with severe COVID‐19, correlating with reduced...

Infection by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been associated with leukopenia and uncontrolled inflammatory response in critically ill patients. A better comprehension of SARS-CoV-2-induced monocyte death is essential for the identification of therapies capable to control the hyper-inflammation and reduce viral r...

Infection by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiological agent of coronavirus disease 2019 (COVID-19), may elicit uncontrolled and damaging inflammatory reactions, due to an excessive immune response and dysregulated production of cytokines and chemokines. Thus, it is critical to identify compounds able to inhibit...

Increased accumulation of cytoplasmic lipid droplets (LDs) in host nonadipose cells is commonly observed in response to numerous infectious diseases, including bacterial, parasite, and fungal infections. LDs are lipid‐enriched, dynamic organelles composed of a core of neutral lipids surrounded by a monolayer of phospholipids associated with a diver...

Lipid droplets (lipid bodies, LDs) are dynamic organelles that have important roles in regulating lipid metabolism, energy homeostasis, cell signaling, membrane trafficking, and inflammation. LD biogenesis, composition, and functions are highly regulated and may vary according to the stimuli, cell type, activation state, and inflammatory environmen...

Most eukaryotic cells contain varying amounts of cytosolic lipidic inclusions termed lipid bodies (LBs) or lipid droplets (LDs). In mammalian cells, such as macrophages, these lipid-rich organelles are formed in response to host-pathogen interaction during infectious diseases and are sites for biosynthesis of arachidonic acid (AA)-derived inflammat...

Arachidonic-acid (AA)-induced lipid body (LB) formation is a rapid and dose-dependent phenomenon within the parasite Trypanosoma cruzi. The dose-response curve of LB genesis was analyzed 1 h after stimulation with AA (1–10 μm). LBs were visualized and enumerated using osmium staining. Results were expressed as mean ± SEM, from at least 3 experiment...

Quantitative ultrastructural analyses of the parasite Trypanosoma cruzi stimulated or not with 7.5 μM arachidonic acid (AA). Samples from unstimulated AA-stimulated parasites were fixed and processed for transmission electron microscopy. A total of 50 electron micrographs (25 from unstimulated and 25 from AA-stimulated groups) were analyzed and the...

Myocarditis elicited by the acute phase of experimental Chagas' disease. (A, B) Histopathological analyses from control (A) and infected animals show myocarditis predominantly mononuclear and diffuse, dissociated myocardial fibers and edematous intersticial tissue. Parasite nests are encircled. Holtzman rats were infected with Trypanosoma cruzi (Y...

Number of lipid bodies (LBs) within trypomastigotes after stimulation with exogenous oleic acid (OA) for 1 h (A) or 24 h (B). Bars represent the mean ± SEM of LBs per parasite from 50 consecutevely counted parasites from at least 4 independent experiments. * P < 0.05 between groups. Cells were enumerated using osmium staining. (TIF)

During acute infection with the parasite Trypanosoma cruzi, the causal agent of Chagas' disease, tissue damage is related to intense tissue parasitism. Here we discuss histological approaches for an optimal visualization and quantification of T. cruzi nests in the heart, the main target organ of the parasite. These analyses are important to evaluat...

Lipid bodies (lipid droplets) are lipid-rich organelles with functions in cell metabolism and signaling. Here, we investigate the mechanisms of Trypanosoma cruzi–induced lipid body formation and their contributions to host-parasite interplay. We demonstrate that T. cruzi–induced lipid body formation in macrophages occurs in a Toll-like receptor 2–d...