Location via proxy:   [ UP ]  
[Report a bug]   [Manage cookies]                
Skip to main content
Luvia E. Sánchez Torres

    Luvia E. Sánchez Torres

    IPN, Immunology, Faculty Member
    Helminths have been present throughout the evolution of humans, promoting the development and maturation of the host immune system. However, this interaction is not exclusive between these two organisms, as the microbiota is also involved... more
    Helminths have been present throughout the evolution of humans, promoting the development and maturation of the host immune system. However, this interaction is not exclusive between these two organisms, as the microbiota is also involved in this human evolutionary process and maintains a balanced relationship inside the host. Consequently, helminths have been forced to interact and co-evolve with the microbiota, shaping microbial communities and allowing the development of reciprocal mechanisms that favour their establishment. This helminth-microbiota association, in turn, induced the activation of different host immunoregulatory pathways to preserve health by preventing the development of some diseases associated with inflammatory immune responses. Unfortunately, this collaborative relationship can be quali- and quantitatively altered by the diet and the use of antibacterial and antihelminthic drugs. Understanding the mechanisms involved in this complex three-way communication that has continued for many years is crucial for preserving health and for the generation of new therapeutic alternatives.
    The development of the parasitoid Doryctobracon crawfordi (Viereck) (Hymenoptera: Braconidae) in Anastrepha obliqua (McQuart) (Diptera: Tephritidae) larvae is unviable in nature; however, if the host larva is irradiated at 160 Gy, the... more
    The development of the parasitoid Doryctobracon crawfordi (Viereck) (Hymenoptera: Braconidae) in Anastrepha obliqua (McQuart) (Diptera: Tephritidae) larvae is unviable in nature; however, if the host larva is irradiated at 160 Gy, the parasitoid develops and emerges successfully. This suggests that radiation affects the immune responses of A. obliqua larvae, while the underlying mechanisms remain to be revealed. Using optical and electronic microscopies we determined the number and type of hemocyte populations found inside the A. obliqua larvae, either nonirradiated, irradiated at 160 Gy, parasitized by D. crawfordi, or irradiated and parasitized. Based on flow cytometry, the capacity to produce reactive oxygen species (ROS) was determined by the 123‐dihydrorhodamine method in those hemocyte cells. Five cell populations were found in the hemolymph of A. obliqua larvae, two of which (granulocytes and plasmatocytes) can phagocytize and produce ROS. A reduction in the number of cells, mainly of the phagocytic type, was observed, as well as the capacity of these cells to produce ROS, when A. obliqua larvae were irradiated. Both radiation and parasitization decreased the ROS production, and when A. obliqua larvae were irradiated followed by parasitization by D. crawfordi, the reduction of the ROS level was even greater. In contrast, a slight increase in the size of these cells was observed in the hemolymph of the parasitized larvae compared to those in nonparasitized larvae. These results suggest that radiation significantly affects the phagocytic cells of A. obliqua and thus permits the development of the parasitoid D. crawfordi.
    Flow cytometry (FC) is widely used in microbiology, immunology, hematology, and oncology. In the veterinary field, FC enabled the study of the immune response in cattle infected with different pathogens, as well as vaccine testing.... more
    Flow cytometry (FC) is widely used in microbiology, immunology, hematology, and oncology. In the veterinary field, FC enabled the study of the immune response in cattle infected with different pathogens, as well as vaccine testing. However, few fluorochrome-conjugated antibodies recognize bovine antigens, limiting the possible benefits of FC and the implementation of multiparametric analysis for more complex studies. Two cytometry panels with five colors each were designed and implemented for the study and identification of populations and subpopulations of T cells derived from the peripheral blood mononuclear cells of dairy heifers. Both panels detected differences in T cell subpopulations between heifers positively and negatively tested for tuberculin; they detected overexpression of CD25+ and CD45RO+ in tuberculin-positive heifers after stimulation with a culture filtrate protein extract (CFPE) from Mycobacterium bovis (M. bovis). We identified subpopulations of T cells from peri...
    The antiphospholipid syndrome (APS), a systemic autoimmune disease characterized by a hypercoagulability associated to vascular thrombosis and/or obstetric morbidity, is caused by the presence of antiphospholipid antibodies such as lupus... more
    The antiphospholipid syndrome (APS), a systemic autoimmune disease characterized by a hypercoagulability associated to vascular thrombosis and/or obstetric morbidity, is caused by the presence of antiphospholipid antibodies such as lupus anticoagulant, anti-β-2-glycoprotein 1, and/or anticardiolipin antibodies. In the obstetrical APS, antiphospholipid antibodies induce the production of proinflammatory cytokines and tissue factor by placental tissues and recruited neutrophils. Moreover, antiphospholipid antibodies activate the complement system which, in turn, induces a positive feedback leading to recruitment of neutrophils as well as activation of the placenta. Activation of these cells triggers myometrial contractions and cervical ripening provoking the induction of labor. In thrombotic and obstetrical APS, antiphospholipid antibodies activate endothelial cells, platelets, and neutrophils and they may alter the multimeric pattern and concentration of von Willebrand factor, increa...
    Amphipterygium adstringensis an endemic species in Mexico commonly known as “cuachalalate.” Healers to treat gastritis, gastric ulcers, and gastrointestinal cancer have traditionally used the bark. We investigated the effects of alcoholic... more
    Amphipterygium adstringensis an endemic species in Mexico commonly known as “cuachalalate.” Healers to treat gastritis, gastric ulcers, and gastrointestinal cancer have traditionally used the bark. We investigated the effects of alcoholic extract ofA. adstringens(AaEE) in DSS-induced colitis in mice. The protective effect of AaEE was determined at 200 mg/kg by oral gavage for 10 days. We determine the effect of AaEE on clinical features (disease activity index), antioxidants, anti-inflammatory, and immunomodulatory activities in relation to the activity of SOD, CAT, and GPx, levels of proinflammatory cytokines, and changes both macroscopic and microscopic of the colonic mucosa. AaEE significantly reduced the inflammation of colon and significantly increased SOD and GPx activities. AaEE also significantly decreased TNF-α, IFN-γ, and IL-1βcytokine levels compared to DSS-treated mice and reduced both infiltration of inflammatory cells and the mucosal damage in colon. The results sugges...
    Brucellosis infection causes non-specific symptoms such as fever, chills, sweating, headaches, myalgia, arthralgia, anorexia, fatigue, and mood disorders. In mouse models, it has been associated with increased levels of IL-6, TNF-α, and... more
    Brucellosis infection causes non-specific symptoms such as fever, chills, sweating, headaches, myalgia, arthralgia, anorexia, fatigue, and mood disorders. In mouse models, it has been associated with increased levels of IL-6, TNF-α, and IFN-γ, a decrease in serotonin and dopamine levels within the hippocampus, induced loss of muscle strength and equilibrium, and increased anxiety and hopelessness. Imipramine (ImiP), a tricyclic antidepressant, is used to alleviate neuropathic pain. This study evaluated the effects of ImiP on Balb/c mice infected with Brucella abortus 2308 (Ba) at 14- and 28-days post-infection. Serum levels of six cytokines (IFN-γ, IL-6, TNF-α, IL-12, MCP-1. and IL-10) were assessed by FACS, while the number of bacteria in the spleen was measured via CFU. Serotonin levels in the hippocampus were analyzed via HPLC, and behavioral tests were conducted to assess strength, equilibrium, and mood. Our results showed that mice infected with Brucella abortus 2308 and treate...
    Leishmaniasis is a neglected vector-borne disease; there are different manifestations of the diseases and species involved, and cutaneous leishmaniasis caused by Leishmania (L.) mexicana is the most prevalent in Mexico. Currently, the... more
    Leishmaniasis is a neglected vector-borne disease; there are different manifestations of the diseases and species involved, and cutaneous leishmaniasis caused by Leishmania (L.) mexicana is the most prevalent in Mexico. Currently, the drugs available for the treatment of leishmaniasis are toxic, expensive, and often ineffective; therefore, it is imperative to carry out research and development of new therapeutic alternatives, with natural products being an attractive option. In particular, oregano is a plant with worldwide distribution; in Mexico, two species: Lippia berlandieri Schauer and Poliomintha longiflora Gray are endemic. Both essential oils (EO’s) have been reported to have antimicrobial activity attributed to their main components, thymol and carvacrol. In this research, the leishmanicidal effect and mechanism of cell death induced by L. berlandieri EO, P. longiflora EO, thymol, and carvacrol in L. mexicana promastigotes were determined in vitro. Additionally, the cytotox...
    La citometría de flujo es una tecnología que ha favorecido el rápido avance de muchas y muy diversas áreas de la ciencia, ya que permite la medición simultánea de múltiples características de cada una de las partículas o células... more
    La citometría de flujo es una tecnología que ha favorecido el rápido avance de muchas y muy diversas áreas de la ciencia, ya que permite la medición simultánea de múltiples características de cada una de las partículas o células individuales que se encuentran en una muestra mientras pasan a gran velocidad a través de una zona iluminada por uno o varios láseres. La información obtenida incluye datos sobre el tamaño y la complejidad interna, así como otros parámetros inherentes a cada una de las partículas presentes en la muestra, los cuales son captados por el equipo como señales luminosas. Las partículas más comúnmente analizadas en los citómetros de flujo son células, así que puede analizarse la expresión de moléculas tanto en su superficie como en su interior, la viabilidad, la funcionalidad, la proliferación celular, el contenido de ADN y la producción de citocinas entre muchas otras. Estas determinaciones pueden realizarse gracias a la utilización de anticuerpos acoplados a fluo...
    The biological activity of essential oils and their major components is well documented. Essential oils such as oregano and cinnamon are known for their effect against bacteria, fungi, and even viruses. The mechanism of action is proposed... more
    The biological activity of essential oils and their major components is well documented. Essential oils such as oregano and cinnamon are known for their effect against bacteria, fungi, and even viruses. The mechanism of action is proposed to be related to membrane and external cell structures, including cell walls. This study aimed to evaluate the biological activity of seven essential oils and eight of their major components against Gram-negative and Gram-positive bacteria, filamentous fungi, and protozoans. The antimicrobial activity was evaluated by determination of the Minimal Inhibitory Concentration for Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, Salmonella Typhimurium, Shigella sonnei, Aspergillus niger, Aspergillus ochraceus, Alternaria alternata, and Fusarium oxysporium, the half-maximal inhibitory concentration (IC50) for Trypanosoma cruzi and Leishmania mexicana, and the median lethal dose (LD50) for Giardia lamblia. Results showed th...
    Antimicrobial resistance is an ever-increasing problem throughout the world and has already reached severe proportions. Two very common neglected tropical diseases are Chagas' disease and leishmaniasis. Chagas' disease is a severe... more
    Antimicrobial resistance is an ever-increasing problem throughout the world and has already reached severe proportions. Two very common neglected tropical diseases are Chagas' disease and leishmaniasis. Chagas' disease is a severe health problem, mainly in Latin America, causing approximately 50000 deaths a year and millions of people are infected. About 25-30% of the patients infected with Trypanosoma cruzi develop the chronic form of the disease. On the other hand, Leishmaniasis represents a complex of diseases with an important clinical and epidemiological diversity. It is endemic in 88 countries 72 of which are developing countries and its estimated there are 12 million people infected and 350 million are in areas with infection risk. On this basis, research on organic compounds that can be used against these two diseases is an important target. A very simple, green, and efficient protocol is developed in which bismuth nitrate pentahydrate is employed as a Lewis acid cat...
    Recently it was discovered that neutrophils can generate extracellular fibers called NET (neutrophil extracellular traps), which are composed of a skeleton of DNA “decorated” with many cytoplasmic –including enzymes– and nuclear... more
    Recently it was discovered that neutrophils can generate extracellular fibers called NET (neutrophil extracellular traps), which are composed of a skeleton of DNA “decorated” with many cytoplasmic –including enzymes– and nuclear components.The NET are a physical barrier that prevent the spread of microorganisms and facilitate the cell death by promoting a high local concentration of antimicrobial molecules. On the other hand, the fibrous structure limits the damage to the tissue where they are generated by restricting the range of molecules that are released by the neutrophil. This paper describes this new form of cell death and the implications this may have on different diseases.
    The presence and phenotype of apoptotic lymphocytes was studied in spleen cell suspensions taken from CB6F1 mice infected with Plasmodium chabaudi chabaudi AS. High levels of apoptotic cells were found, associated with high parasitaemias... more
    The presence and phenotype of apoptotic lymphocytes was studied in spleen cell suspensions taken from CB6F1 mice infected with Plasmodium chabaudi chabaudi AS. High levels of apoptotic cells were found, associated with high parasitaemias and splenomegaly. This was also accompanied by expansion and disarray of spleen white pulp. Apoptosis levels lowered when parasitaemia was cleared, but were still higher than in normal mice. At this time, the spleen was diminishing in size and the white pulp was contracting and rearranging. When parasitaemia was patent, the cells most affected by apoptosis were CD4+ T cells followed by CD8+ T cells, and to a lesser extent B220+ B cells. When parasitaemia was cleared, CD8+ T cells and B220+ B cells returned to basal levels of apoptosis, while CD4+ T cells still had higher apoptosis levels than normal mice. A similar pattern of lymphocyte subpopulation apoptosis was found in infected BALB/c mice, despite the fact that, for this mouse model, it has been reported that B cells are the cells that are most affected by apoptosis. We consider that the high levels of apoptosis in CD4+ T cells when parasitaemias are still high are not easily explained by a normal mechanism of down regulation of the immune response.
    CB6F1 mice infected with the nonlethal Plasmodium chabaudi chabaudi AS suffer parasitaemia levels up to 40% (full parasitaemia, FP) and develop both homologous and heterologous (against the lethal Plasmodium yoelii 17XL) protective... more
    CB6F1 mice infected with the nonlethal Plasmodium chabaudi chabaudi AS suffer parasitaemia levels up to 40% (full parasitaemia, FP) and develop both homologous and heterologous (against the lethal Plasmodium yoelii 17XL) protective immunity. However, if mice are treated with anti-malarial drug when parasitaemia is below 10% (low parasitaemia, LP), they only develop homologous immunity. For the better understanding of this interesting dissociation related to the degree of parasitaemia, in this work, we studied the genetic expression of some cytokines. We found that during primary parasitaemia both FP and LP mice showed at first a TNF-alpha, IL-2 and IFN-gamma response which is followed by an IL-4 and IL-10 response. When FP and LP mice were challenged with either the homologous (FP + AS and LP + AS mice) or the heterologous parasite (FP + 17XL and LP + 17XL mice), we observed that LP + 17XL mice, which failed to develop heterologous immunity and succumbed to the challenge, showed a stronger IFN-gamma and a weaker IL-10 expression than FP + 17XL mice, which developed heterologous immunity and survived the challenge. The importance and the possible implications of these findings are discussed.
    Background: Essential oils and their constituents are commonly known for their antibacterial, antifungal and antiparasitic activity, and there are also reports on the antimycobacterial properties, but more experimental data are needed for... more
    Background: Essential oils and their constituents are commonly known for their antibacterial, antifungal and antiparasitic activity, and there are also reports on the antimycobacterial properties, but more experimental data are needed for the description of the mechanism of action or structural (and molecular) properties related to the antimicrobial activity. Methods: Twenty-five constituents of essential oils were evaluated against Mycobacterium tuberculosis H37Rv and Mycobacterium bovis AN5 by the Alamar Blue technique. Twenty compounds were modeled using in silico techniques descriptor generation and subsequent QSAR model building using genetic algorithms. The p-cymene, menthol, carvacrol and thymol were studied at the quantum mechanical level through the mapping of HOMO and LUMO orbitals. The cytotoxic activity against macrophages (J774A) was also evaluated for these four compounds using the Alamar Blue technique. Results: All compounds tested showed to be active antimicrobials ...
    Más de la mitad de la población humana está expuesta a contraer infecciones transmitidas por mosquitos. El cambio climático y la aparición de cepas resistentes a los insecticidas tradicionalmente utilizados han motivado la búsqueda de... more
    Más de la mitad de la población humana está expuesta a contraer infecciones transmitidas por mosquitos. El cambio climático y la aparición de cepas resistentes a los insecticidas tradicionalmente utilizados han motivado la búsqueda de nuevos agentes capaces de controlar las poblaciones de mosquitos. Los aceites esenciales han resultado ser eficaces agentes repelentes y larvicidas.El objetivo de este trabajo fue revisar las investigaciones llevadas a cabo en los últimos años sobre la actividad larvicida de los aceites esenciales y sus componentes contra mosquitos de los géneros Aedes, Anopheles y Culex, así como los últimos reportes sobre su posible mecanismo de acción.
    Los cambios socioeconomicos y las intervencionessanitarias han mejorado la salud de la poblacionmundial en las ultimas decadas. Sin embargo,han empezado a presentarse modificaciones enla distribucion de ciertas enfermedades... more
    Los cambios socioeconomicos y las intervencionessanitarias han mejorado la salud de la poblacionmundial en las ultimas decadas. Sin embargo,han empezado a presentarse modificaciones enla distribucion de ciertas enfermedades debidas,principalmente, a lo que se conoce como cambioclimatico y que es una consecuencia mas deldeterioro del medio ambiente.Una de las preocupaciones derivadas de loanterior es la redistribucion o nueva geolocalizacionde las enfermedades transmitidas por vectores(ETV), ya que los vectores que las transmiten estanencontrando nuevos nichos ecologicos en los cualesestablecerse y multiplicarse. El objetivo de la presenterevision fue conjuntar la evidencia cientifica en tornoal cambio climatico y sus efectos en las ETV.
    S. Andrade Ochoa*, K.F. Chacon Vargas*, J. Correa Basurto, L.M. Rodriguez Valdez, G.V. Nevarez Moorillon and L. E. Sanchez Torres** 1 ENCB-IPN. Prolongacion de Carpio y Plan de Ayala s/n, Col. Casco de Santo Tomas, Delegacion Miguel... more
    S. Andrade Ochoa*, K.F. Chacon Vargas*, J. Correa Basurto, L.M. Rodriguez Valdez, G.V. Nevarez Moorillon and L. E. Sanchez Torres** 1 ENCB-IPN. Prolongacion de Carpio y Plan de Ayala s/n, Col. Casco de Santo Tomas, Delegacion Miguel Hidalgo, C.P. 11340, Mexico, D.F. Mexico 2 ESM-IPN. Plan de San Luis y Diaz Miron s/n, Col. Casco de Santo Tomas, Delegacion Miguel Hidalgo, C.P. 11340, Mexico, D.F. Mexico 3 FCQ-UACH. Campus Universitario #2 s/n, Circuito Universitario. C.P. 31125, Chihuahua, Chihuahua. Mexico * Both authors contributed equally to this work ** Corresponding author: email: luviasanchez@hotmail.com
    Cerebral malaria (CM) is a neurological complication derived from the Plasmodium falciparum infection in humans. The mechanisms involved in the disease progression are still not fully understood, but both the sequestration of infected red... more
    Cerebral malaria (CM) is a neurological complication derived from the Plasmodium falciparum infection in humans. The mechanisms involved in the disease progression are still not fully understood, but both the sequestration of infected red blood cells (iRBC) and leukocytes and an exacerbated host inflammatory immune response are significant factors. In this study, we investigated the effect of Monocyte Locomotion Inhibitory Factor (MLIF), an anti-inflammatory peptide, in a well-characterized murine model of CM. Our data showed that the administration of MLIF increased the survival and avoided the neurological signs of CM in Plasmodium berghei ANKA (PbA) infected C57BL/6 mice. MLIF administration down-regulated systemic inflammatory mediators such as IFN-γ, TNF-α, IL-6, CXCL2, and CCL2, as well as the in situ expression of TNF-α in the brain. In the same way, MLIF reduced the expression of CD31, CD36, CD54, and CD106 in the cerebral endothelium of infected animals and prevented the sequestration of iRBC and leucocytes in the brain microvasculature. Furthermore, MLIF inhibited the activation of astrocytes and microglia and preserved the integrity of the blood-brain barrier (BBB). In conclusion, our results demonstrated that the administration of MLIF increased survival and conferred neuroprotection by decreasing neuroinflammation in murine CM.
    The larvicidal activity of essential oils cinnamon (J. Presl), Mexican lime (Swingle) cumin (Linnaeus), clove ((L.) Merr. & L.M.Perry), laurel (Linnaeus), Mexican oregano (Schauer) and anise (Linnaeus)) and their major components are... more
    The larvicidal activity of essential oils cinnamon (J. Presl), Mexican lime (Swingle) cumin (Linnaeus), clove ((L.) Merr. & L.M.Perry), laurel (Linnaeus), Mexican oregano (Schauer) and anise (Linnaeus)) and their major components are tested against larvae and pupae ofSay. Third instar larvae and pupae are used for determination of lethality and mortality. Essential oils with more than 90% mortality after a 30-min treatment are evaluated at different time intervals. Of the essential oils tested, anise and Mexican oregano are effective against larvae, with a median lethal concentration (LC) of 4.7 and 6.5 µg/mL, respectively. Anise essential oil and-anethole are effective against pupae, with LCvalues of 102 and 48.7 µg/mL, respectively. Oregano essential oil and carvacrol also have relevant activities. A kinetic analysis of the larvicidal activity, the oviposition deterrent effect and assays of the effects of the binary mixtures of chemical components are undertaken. Results show that...
    In the pathogenic Mycobacterium tuberculosis H37Rv, the causative agent of tuberculosis, the genetic and biochemical mechanisms for initiation of DNA replication are largely unknown. In the present study, we have characterized the... more
    In the pathogenic Mycobacterium tuberculosis H37Rv, the causative agent of tuberculosis, the genetic and biochemical mechanisms for initiation of DNA replication are largely unknown. In the present study, we have characterized the physical interactions between M. tuberculosis DnaA and DnaB using both in vivo methods, such as bacterial two-hybrid assays, and in vitro techniques, such as surface plasmon resonance (SPR) and Pull-down/Western blotting. The full-length N-terminus (1-206 residues) of DnaB was found to interact with DnaA, while the shorter N-terminal domain of DnaB (1-125 residues), which lacked the linker region, did not. Further SPR and electrophoretic mobility shift assays indicated that the N-terminus (1-206 residues) of DnaB also had a critical role in regulating DnaA complex formation at the origin of replication (OriC). This regulatory effect was not obviously observed for DNA substrates containing only two DnaA-boxes. This is the first report showing a physical interaction between DnaA and replicative helicase DnaB from M. tuberculosis and the role in subsequent DnaA-OriC interactions. The findings reported here further the understanding of the regulatory mechanisms for initiation of DNA replication in this important human pathogen.
    PD-L1 expression plays a critical role in the impairment of T cell responses during chronic infections; however, the expression of PD-L1 on T cells during acute viral infections, particularly during the pandemic influenza virus... more
    PD-L1 expression plays a critical role in the impairment of T cell responses during chronic infections; however, the expression of PD-L1 on T cells during acute viral infections, particularly during the pandemic influenza virus (A(H1N1)pdm09), and its effects on the T cell response have not been widely explored. We found that A(H1N1)pdm09 virus induced PD-L1 expression on human dendritic cells (DCs) and T cells, as well as PD-1 expression on T cells. PD-L1 expression impaired the T cell response against A(H1N1)pdm09 by promoting CD8+T cell death and reducing cytokine production. Furthermore, we found increased PD-L1 expression on DCs and T cells from influenza-infected patients from the first and second 2009 pandemic waves in Mexico City. PD-L1 expression on CD8+T cells correlated inversely with T cell proportions in patients infected with A(H1N1)pdm09. Therefore, PD-L1 expression on DCs and T cells could be associated with an impaired T cell response during acute infection with A(H...
    Cyrtocarpa procera is a plant used in traditional Mexican medicine to treat different gastrointestinal problems. Here, we investigated the effects of a C. procera methanolic extract in DSS-induced colitis mice. Ulcerative colitis (UC) was... more
    Cyrtocarpa procera is a plant used in traditional Mexican medicine to treat different gastrointestinal problems. Here, we investigated the effects of a C. procera methanolic extract in DSS-induced colitis mice. Ulcerative colitis (UC) was induced by administering 4% DSS in drinking water to female BALB/c mice. Compared to untreated mice with UC, the treatment group receiving the C. procera extract presented less severe UC symptoms of diarrhea, bleeding, and weight loss. Additionally, colon shortening was significantly reduced, and at the microscopic level, only minor damage was observed. Levels of proinflammatory cytokines such as TNF-α, IL-1β, and IFNγ in serum as well as the MPO activity in the colon were significantly reduced in the C. procera methanolic extract-treated group. Moreover, the extract of C. procera reduced oxidative stress during UC, preventing the deterioration of the activity of antioxidant enzymes such as SOD, CAT, and GPx. Additionally, the extract decreased lipid peroxidation damage and its final products, such as malondialdehyde (MDA). In agreement with this, in vitro assays with the C. procera extract displayed good antioxidant capacity, probably due to the presence of polyphenolic compounds, in particular the flavonoids that were identified, such as chrysin, naringenin, kaempferol, and catechin, which have been reported to have antiinflammatory and antioxidant activities. Therefore, the improvement of UC by the C. procera methanolic extract may be related to the action mechanisms of these compounds.
    Cerebral malaria (CM) is a neurological complication derived from the Plasmodium falciparum infection in humans. The mechanisms involved in the disease progression are still not fully understood, but both the sequestration of infected red... more
    Cerebral malaria (CM) is a neurological complication derived from the Plasmodium falciparum infection in humans. The mechanisms involved in the disease progression are still not fully understood, but both the sequestration of infected red blood cells (iRBC) and leukocytes and an exacerbated host inflammatory immune response are significant factors. In this study, we investigated the effect of Monocyte Locomotion Inhibitory Factor (MLIF), an anti-inflammatory peptide, in a well-characterized murine model of CM. Our data showed that the administration of MLIF increased the survival and avoided the neurological signs of CM in Plasmodium berghei ANKA (PbA) infected C57BL/6 mice. MLIF administration down-regulated systemic inflammatory mediators such as IFN-γ, TNF-α, IL-6, CXCL2, and CCL2, as well as the in situ expression of TNF-α in the brain. In the same way, MLIF reduced the expression of CD31, CD36, CD54, and CD106 in the cerebral endothelium of infected animals and prevented the sequestration of iRBC and leucocytes in the brain microvasculature. Furthermore, MLIF inhibited the activation of astrocytes and microglia and preserved the integrity of the blood-brain barrier (BBB). In conclusion, our results demonstrated that the administration of MLIF increased survival and conferred neuroprotection by decreasing neuroinflammation in murine CM.
    Dengue is a worldwide expanding threat caused by dengue virus (DENV) infection. To date, no specific treatment or effective vaccine is available. Antibodies produced by plasma cells (PCs) might be involved concomitantly in protection and... more
    Dengue is a worldwide expanding threat caused by dengue virus (DENV) infection. To date, no specific treatment or effective vaccine is available. Antibodies produced by plasma cells (PCs) might be involved concomitantly in protection and severe dengue immunopathology. Although a massive appearance of PCs has been reported during acute DENV infection in humans, this response has been poorly characterized. Here, we show the dynamic of PC generation in immune-competent mice cutaneously inoculated with DENV compared with two control experimental groups: mice inoculated with inactivated DENV or with PBS. We found that PC numbers increased significantly in the skin-draining lymph node (DLN), peaking at day 10 and abruptly decreasing by day 14 after DENV inoculation. Class-switched IgG+ PCs appeared from day 7 and dominated the response, while in contrast, the frequency of IgM+ PCs decreased from day 7 onwards. Even though the kinetic of the response was similar between DENV- and iDENV-ino...
    Ursolic and oleanolic acids are natural isomeric triterpenes known for their anticancer activity. Here, we investigated the effect of triterpenes on the viability of A549 human lung cancer cells and the role of autophagy in their... more
    Ursolic and oleanolic acids are natural isomeric triterpenes known for their anticancer activity. Here, we investigated the effect of triterpenes on the viability of A549 human lung cancer cells and the role of autophagy in their activity. The induction of autophagy, the mitochondrial changes and signaling pathway stimulated by triterpenes were systematically explored by confocal microscopy and western blotting. Ursolic and oleanolic acids induce autophagy in A549 cells. Ursolic acid activates AKT/mTOR pathways and oleanolic acid triggers a pathway independent on AKT. Both acids promote many mitochondrial changes, suggesting that mitochondria are targets of autophagy in a process known as mitophagy. The PINK1/Parkin axis is a pathway usually associated with mitophagy, however, the mitophagy induced by ursolic or oleanolic acid is just dependent on PINK1. Moreover, both acids induce an ROS production. The blockage of autophagy with wortmannin is responsible for a decrease of mitochon...

    And 29 more