Uener Ribeiro dos Santos
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Research Subjects
Uener Ribeiro dos Santos has a total of 84 co-authors. Here are the top co-authors by number of shared publications:
- Jane Lima dos Santos
Departamento de Ciências Biológicas, Universidade Estadual de Santa Cruz, Bahia, Brazil
5 shared publications - Sandra Rocha Gadelha
Laboratório de Farmacogenômica e Epidemiologia Molecular, Universidade Estadual de Santa Cruz, Ilhéus 45662-900, Bahia, Brazil
4 shared publications - Galileu Barbosa Costa
Departamento de Ciências da Saúde, Universidade Estadual de Santa Cruz, Ilhéus, Brazil
3 shared publications - Ana Paula Melo Mariano
Laboratório de Farmacogenômica e Epidemiologia Molecular, Universidade Estadual de Santa Cruz, Ilhéus 45662-900, Bahia, Brazil
2 shared publications - George Rêgo Albuquerque
Laboratory of Biotechnology and Animal Health (LABSA), State University of Santa Cruz (UESC), Ilhéus, Brazil
2 shared publications A. P. M. Mariano
Laboratório de Farmacogenômica e Epidemiologia Molecular,Departamento de Ciências Biológicas,Universidade Estadual de Santa Cruz,Ilhéus,Bahia,Brazil
1 shared publication
Latest Publications
- Open Access
- 23 October 2026
- Published by MDPI AG in Zoonotic Diseases
- Vol. 6 (4) , 48
A Methodological Framework for Epidemiological Data Analysis: Dengue as a Model for Disease Surveillance and a One Health Perspective
Zoonotic and vector-borne diseases remain important public health problems, especially in regions where social, environmental, and epidemiological conditions favor their occurrence and spread. Transparent procedures for data organization, analysis, and interpretation are essential for translating epidemiological findings into public health information. In this context, dengue is an important model for epidemiological surveillance because its occurrence across diverse geographic settings involves seasonal patterns and demographic and environmental factors. Here, we propose a practical and structured framework for epidemiological data analysis in vector-borne diseases that can be applied to zoonotic diseases. We provide a step-by-step guide to organizing data, selecting descriptive and analytical methods, and interpreting results, using dengue as a model for disease surveillance and a One Health perspective. The framework is divided into five parts: (1) defining study scope and design, (2) conducting descriptive analysis, (3) examining association analyses of sociodemographic and clinical variables, (4) fitting multivariable analysis to integrate human and environmental data, and (5) performing statistical analysis through a step-by-step protocol. It combines dengue notification data with meteorological records to illustrate analyses at individual and population levels, while distinguishing observational associations from causal conclusions. The protocol demonstrates the analytical procedures using a freely available, user-friendly statistical software. The concepts and methodological approaches presented here can be adapted to other diseases according to their data sources, outcomes, and epidemiological context, supporting the development of epidemiological studies for disease surveillance, prevention, and control.
- 23 October 2026
- Published by MDPI AG in Zoonotic Diseases
- Vol. 6 (4) , 48
Open AccessA Methodological Framework for Epidemiological Data Analysis: Dengue as a Model for Disease Surveillance and a One Health Perspective
Zoonotic and vector-borne diseases remain important public health problems, especially in regions where social, environmental, and epidemiological conditions favor their occurrence and spread. Transparent procedures for data organization, analysis, and interpretation are essential for translating epidemiological findings into public health information. In this context, dengue is an important model for epidemiological surveillance because its occurrence across diverse geographic settings involves seasonal patterns and demographic and environmental factors. Here, we propose a practical and structured framework for epidemiological data analysis in vector-borne diseases that can be applied to zoonotic diseases. We provide a step-by-step guide to organizing data, selecting descriptive and analytical methods, and interpreting results, using dengue as a model for disease surveillance and a One Health perspective. The framework is divided into five parts: (1) defining study scope and design, (2) conducting descriptive analysis, (3) examining association analyses of sociodemographic and clinical variables, (4) fitting multivariable analysis to integrate human and environmental data, and (5) performing statistical analysis through a step-by-step protocol. It combines dengue notification data with meteorological records to illustrate analyses at individual and population levels, while distinguishing observational associations from causal conclusions. The protocol demonstrates the analytical procedures using a freely available, user-friendly statistical software. The concepts and methodological approaches presented here can be adapted to other diseases according to their data sources, outcomes, and epidemiological context, supporting the development of epidemiological studies for disease surveillance, prevention, and control.
- Open Access
The Impact of the COVID-19 Pandemic on the Clinical and Epidemiological Profile of Severe Acute Respiratory Infection in Bahia, Brazil: A Comparative Analysis of Pre- and Post-Pandemic Trends
In recent years, the incidence of Severe Acute Respiratory Infection (SARI) has increased due to the emergence of SARS-CoV-2. However, the impact of the COVID-19 pandemic extends beyond mortality rates. Recent analyses suggest that the introduction and spread of SARS-CoV-2 have significantly affected the epidemiology of other key respiratory viruses, such as influenza virus (FLUV), respiratory syncytial virus (RSV), and rhinovirus (RV). These changes raise new questions about the dynamics and incidence of post-COVID-19 respiratory infections, as well as potential alterations in symptom profiles and clinical outcomes. In this study, we analyzed data from the Epidemiological Surveillance Information System of Respiratory Viral Agents (SIVEP-Gripe), established by the Brazilian Ministry of Health, to examine the profile of SARI before and during the COVID-19 pandemic in Brazil. Our data reveal a distinct epidemiological pattern, with a significant decrease in FLUV notifications during the pandemic, accompanied by peaks in RSV and RV cases in late 2020. Additionally, there was a shift in the age distribution of RSV and other viral infections, with individuals infected during the pandemic being older than those infected before the pandemic. Interestingly, the introduction and spread of SARS-CoV-2 in Bahia State resulted in a reduction in the frequency of symptoms associated with non-SARS-CoV-2 SARI, without altering clinical outcomes. Our findings suggest that the circulation of SARS-CoV-2 has contributed to a clinical and epidemiological shift, particularly for FLUV, RSV, and other viruses, marked by a reduction in symptoms such as fever, dyspnea, respiratory distress, and the need for ventilatory support. The underlying mechanisms driving these changes remain unclear. These insights are crucial for public health authorities and policymakers to refine surveillance strategies and enhance control measures for respiratory viruses, particularly those causing SARI.
Open AccessThe Impact of the COVID-19 Pandemic on the Clinical and Epidemiological Profile of Severe Acute Respiratory Infection in Bahia, Brazil: A Comparative Analysis of Pre- and Post-Pandemic Trends
In recent years, the incidence of Severe Acute Respiratory Infection (SARI) has increased due to the emergence of SARS-CoV-2. However, the impact of the COVID-19 pandemic extends beyond mortality rates. Recent analyses suggest that the introduction and spread of SARS-CoV-2 have significantly affected the epidemiology of other key respiratory viruses, such as influenza virus (FLUV), respiratory syncytial virus (RSV), and rhinovirus (RV). These changes raise new questions about the dynamics and incidence of post-COVID-19 respiratory infections, as well as potential alterations in symptom profiles and clinical outcomes. In this study, we analyzed data from the Epidemiological Surveillance Information System of Respiratory Viral Agents (SIVEP-Gripe), established by the Brazilian Ministry of Health, to examine the profile of SARI before and during the COVID-19 pandemic in Brazil. Our data reveal a distinct epidemiological pattern, with a significant decrease in FLUV notifications during the pandemic, accompanied by peaks in RSV and RV cases in late 2020. Additionally, there was a shift in the age distribution of RSV and other viral infections, with individuals infected during the pandemic being older than those infected before the pandemic. Interestingly, the introduction and spread of SARS-CoV-2 in Bahia State resulted in a reduction in the frequency of symptoms associated with non-SARS-CoV-2 SARI, without altering clinical outcomes. Our findings suggest that the circulation of SARS-CoV-2 has contributed to a clinical and epidemiological shift, particularly for FLUV, RSV, and other viruses, marked by a reduction in symptoms such as fever, dyspnea, respiratory distress, and the need for ventilatory support. The underlying mechanisms driving these changes remain unclear. These insights are crucial for public health authorities and policymakers to refine surveillance strategies and enhance control measures for respiratory viruses, particularly those causing SARI.
- 1 January 2025
- Published by Canadian Science Publishing in Canadian Journal of Microbiology
- Vol. 71, 1-15
Lessons from the field: Trichoderma in agriculture and human health
The use of Trichoderma in agriculture as both a biocontrol agent and biofertilizer hinges on its ability to colonize the rhizosphere, promote plant growth, endure adverse environments, compete for space and nutrients, and produce enzymes and secondary metabolites to mycoparasitize and infect other fungus. In humans, Trichoderma exhibits the capacity to infect various bodily tissues, leading to Trichodermosis. There has been a notable increase in cases ranging from superficial to fatal, invasive, and disseminated infections, particularly among immunocompromised individuals. Trichoderma species employ diverse strategies to colonize and survive in various environments, infecting phytopathogens; however, the mechanisms and virulence factors contributing to human infections remain poorly understood. In this mini review, we provide a brief overview and contextualization of the virulence mechanisms employed by Trichoderma in parasitizing other fungi, as well as those implicated in modulating plant immunity and inducing human infections. Furthermore, we discuss the similarity of these virulence factors capable of modulating the mammalian immune system and their potential implications for human infection.
- 1 January 2025
- Published by Canadian Science Publishing in Canadian Journal of Microbiology
- Vol. 71, 1-15
Lessons from the field: Trichoderma in agriculture and human health
The use of Trichoderma in agriculture as both a biocontrol agent and biofertilizer hinges on its ability to colonize the rhizosphere, promote plant growth, endure adverse environments, compete for space and nutrients, and produce enzymes and secondary metabolites to mycoparasitize and infect other fungus. In humans, Trichoderma exhibits the capacity to infect various bodily tissues, leading to Trichodermosis. There has been a notable increase in cases ranging from superficial to fatal, invasive, and disseminated infections, particularly among immunocompromised individuals. Trichoderma species employ diverse strategies to colonize and survive in various environments, infecting phytopathogens; however, the mechanisms and virulence factors contributing to human infections remain poorly understood. In this mini review, we provide a brief overview and contextualization of the virulence mechanisms employed by Trichoderma in parasitizing other fungi, as well as those implicated in modulating plant immunity and inducing human infections. Furthermore, we discuss the similarity of these virulence factors capable of modulating the mammalian immune system and their potential implications for human infection.
- Open Access
- 20 November 2024
- Published by MDPI AG in Microorganisms
- Vol. 12 (11) , 2366
Recombinant SAG2A Protein from Toxoplasma gondii Modulates Immune Profile and Induces Metabolic Changes Associated with Reduced Tachyzoite Infection in Peritoneal Exudate Cells from Susceptible C57BL/6 Mice
Toxoplasmosis is a neglected disease that represents a significant public health problem. The antigenic profile of T. gondii is complex, and the immune response can lead to either susceptibility or resistance. Some antigens, such as surface antigen glycoprotein (SAG), are expressed on the surface of tachyzoite stages and interact with the host immune cells. In this study, we investigated the potential of the recombinant SAG2A protein of T. gondii to control parasitism and modulate the immune response in the peritoneal exudate cells (PECs) of both susceptible (C57BL/6) and resistant (BALB/c) mice using an in vitro infection model, gene expression, proteomic analysis, and bioinformatic tools. Our results showed that rSAG2A-treated PECs presented a lower parasitism in C57BL/6 mice but not in the PECs from BALB/c mice, and induced a pro-inflammatory cytokine profile in C57BL/6 mice (iNOS, TNF-α, and IL-6). rSAG2A modulated different exclusive proteins in each mouse lineage, with PECs from the C57BL/6 mice being more sensitive to modulation by rSAG2A. Additionally, biological processes crucial to parasite survival and immune response were modulated by rSAG2A in the C57BL/6 PECs, including fatty acid beta-oxidation, reactive oxygen species metabolism, interferon production, and cytokine-mediated signaling pathways. Together, our study indicates that rSAG2A controls T. gondii parasitism in susceptible C57BL/6 PECs through the modulation of pro-inflammatory cytokines and enhanced expression of proteins involved in the cytotoxic response.
- 20 November 2024
- Published by MDPI AG in Microorganisms
- Vol. 12 (11) , 2366
Open AccessRecombinant SAG2A Protein from Toxoplasma gondii Modulates Immune Profile and Induces Metabolic Changes Associated with Reduced Tachyzoite Infection in Peritoneal Exudate Cells from Susceptible C57BL/6 Mice
Toxoplasmosis is a neglected disease that represents a significant public health problem. The antigenic profile of T. gondii is complex, and the immune response can lead to either susceptibility or resistance. Some antigens, such as surface antigen glycoprotein (SAG), are expressed on the surface of tachyzoite stages and interact with the host immune cells. In this study, we investigated the potential of the recombinant SAG2A protein of T. gondii to control parasitism and modulate the immune response in the peritoneal exudate cells (PECs) of both susceptible (C57BL/6) and resistant (BALB/c) mice using an in vitro infection model, gene expression, proteomic analysis, and bioinformatic tools. Our results showed that rSAG2A-treated PECs presented a lower parasitism in C57BL/6 mice but not in the PECs from BALB/c mice, and induced a pro-inflammatory cytokine profile in C57BL/6 mice (iNOS, TNF-α, and IL-6). rSAG2A modulated different exclusive proteins in each mouse lineage, with PECs from the C57BL/6 mice being more sensitive to modulation by rSAG2A. Additionally, biological processes crucial to parasite survival and immune response were modulated by rSAG2A in the C57BL/6 PECs, including fatty acid beta-oxidation, reactive oxygen species metabolism, interferon production, and cytokine-mediated signaling pathways. Together, our study indicates that rSAG2A controls T. gondii parasitism in susceptible C57BL/6 PECs through the modulation of pro-inflammatory cytokines and enhanced expression of proteins involved in the cytotoxic response.
- Open Access
SARS-CoV-2 Infection in Cities from the Southern Region of Bahia State, Brazil: Analysis of Variables Associated in Both Individual and Community Level
The COVID-19 pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), challenged public health systems worldwide. Individuals in low-income countries/regions are still at individual and community risk concerning inequality, sanitation, and economic conditions. Besides, during the pandemic, the transmission in municipalities and communities in the countryside and less developed regions kept viral spread and required structured and strengthened clinical and laboratory surveillance. Here, we present an observational, analytic, cross-sectional study conducted using secondary data from the Laboratório de Farmacogenômica e Epidemiologia Molecular (LAFEM)-Universidade Estadual de Santa Cruz (UESC), to evaluate individual and community factors associated to SARS-CoV-2 infection in outpatients from different cities from Southern Region of Bahia State, in Brazil. The data were collected between June 2021 and May 2022. The SARS-CoV-2 positivity by RT-qPCR was correlated with low socio-economic indicators, including the Human development index (HDIc) and Average worker salary (AWSc). Besides, in general, females were less likely to test positive for SARS-CoV-2 (OR = 0.752; CI 95% 0.663–0.853; p < 0.0001), while brown individuals had more positivity for infection (p < 0.0001). In addition, those who had clinical symptoms were more likely to test positive for SARS-CoV-2 (OR = 6.000; CI 95% 4.932–7.299; p < 0.0001). Although dry cough, headache, and fever were the most frequent, loss of taste (OR = 5.574; CI 95% 4.334–7.186) and loss of smell (OR = 6.327; CI 95% 4.899–8.144) presented higher odds ratio to be positive to SARS-CoV-2 by RT-qPCR. Nonetheless, the distribution of these characteristics was not homogenous among the different cities, especially for age and gender. The dynamic of SARS-CoV-2 positivity differed between cities and the total population and reinforces the hypothesis that control strategies for prevention needed to be developed based on both individual and community risk levels to mitigate harm to individuals and the health system.
Open AccessSARS-CoV-2 Infection in Cities from the Southern Region of Bahia State, Brazil: Analysis of Variables Associated in Both Individual and Community Level
The COVID-19 pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), challenged public health systems worldwide. Individuals in low-income countries/regions are still at individual and community risk concerning inequality, sanitation, and economic conditions. Besides, during the pandemic, the transmission in municipalities and communities in the countryside and less developed regions kept viral spread and required structured and strengthened clinical and laboratory surveillance. Here, we present an observational, analytic, cross-sectional study conducted using secondary data from the Laboratório de Farmacogenômica e Epidemiologia Molecular (LAFEM)-Universidade Estadual de Santa Cruz (UESC), to evaluate individual and community factors associated to SARS-CoV-2 infection in outpatients from different cities from Southern Region of Bahia State, in Brazil. The data were collected between June 2021 and May 2022. The SARS-CoV-2 positivity by RT-qPCR was correlated with low socio-economic indicators, including the Human development index (HDIc) and Average worker salary (AWSc). Besides, in general, females were less likely to test positive for SARS-CoV-2 (OR = 0.752; CI 95% 0.663–0.853; p < 0.0001), while brown individuals had more positivity for infection (p < 0.0001). In addition, those who had clinical symptoms were more likely to test positive for SARS-CoV-2 (OR = 6.000; CI 95% 4.932–7.299; p < 0.0001). Although dry cough, headache, and fever were the most frequent, loss of taste (OR = 5.574; CI 95% 4.334–7.186) and loss of smell (OR = 6.327; CI 95% 4.899–8.144) presented higher odds ratio to be positive to SARS-CoV-2 by RT-qPCR. Nonetheless, the distribution of these characteristics was not homogenous among the different cities, especially for age and gender. The dynamic of SARS-CoV-2 positivity differed between cities and the total population and reinforces the hypothesis that control strategies for prevention needed to be developed based on both individual and community risk levels to mitigate harm to individuals and the health system.
- 6 February 2023
- Published by Taylor & Francis in Journal of Toxicology and Environmental Health, Part B
- Vol. 26 (2) , 97-126
Trichoderma after crossing kingdoms: infections in human populations
Trichoderma is a saprophytic fungus that is used worldwide as a biocontrol and biofertilizer agent. Although considered nonpathogenic until recently, reports of human infections produced by members of the Trichoderma genus are increasing. Numerous sources of infection were proposed based upon patient data and phylogenetic analysis, including air, agriculture, and healthcare facilities, but the deficit of knowledge concerning Trichoderma infections makes patient treatment difficult. These issues are compounded by isolates that present profiles which exhibit high minimum inhibitory concentration values to available antifungal drugs. The aim of this review is to present the global distribution and sources of infections that affect both immunocompetent and immunocompromised hosts, clinical features, therapeutic strategies that are used to treat patients, as well as highlighting treatments with the best responses. In addition, the antifungal susceptibility profiles of Trichoderma isolates that have emerged in recent decades were examined and which antifungal drugs need to be further evaluated as potential candidates to treat Trichoderma infections are also indicated.
- 6 February 2023
- Published by Taylor & Francis in Journal of Toxicology and Environmental Health, Part B
- Vol. 26 (2) , 97-126
Trichoderma after crossing kingdoms: infections in human populations
Trichoderma is a saprophytic fungus that is used worldwide as a biocontrol and biofertilizer agent. Although considered nonpathogenic until recently, reports of human infections produced by members of the Trichoderma genus are increasing. Numerous sources of infection were proposed based upon patient data and phylogenetic analysis, including air, agriculture, and healthcare facilities, but the deficit of knowledge concerning Trichoderma infections makes patient treatment difficult. These issues are compounded by isolates that present profiles which exhibit high minimum inhibitory concentration values to available antifungal drugs. The aim of this review is to present the global distribution and sources of infections that affect both immunocompetent and immunocompromised hosts, clinical features, therapeutic strategies that are used to treat patients, as well as highlighting treatments with the best responses. In addition, the antifungal susceptibility profiles of Trichoderma isolates that have emerged in recent decades were examined and which antifungal drugs need to be further evaluated as potential candidates to treat Trichoderma infections are also indicated.
- Open Access
- 24 October 2022
- Published by Sociedade Brasileira de Computação
- p. 1346-1350
Vidas em jogo: o dilema da maternidade e paternidade na adolescência
O “Vidas em jogo: o dilema da maternidade/paternidade na adolescência” é um jogo educativo elaborado para acentuar a reflexão sobre o impacto individual e social da gravidez precoce. Em versão analógica, foi aplicado como atividade para discentes de ensino fundamental e médio em escolas públicas da Região Sul da Bahia e consiste na análise de um banco de figuras que representam momentos do desenvolvimento biopsicossocial do ser humano a partir do seu nascimento. Aqui, propomos a versão digital dessa atividade analógica, onde os adolescentes são desafiados a confrontar suas necessidades e vontades com as necessidades e responsabilidades que serão desempenhadas em decorrência da Gravidez na adolescência (GA).
- 24 October 2022
- Published by Sociedade Brasileira de Computação
- p. 1346-1350
Open AccessVidas em jogo: o dilema da maternidade e paternidade na adolescência
O “Vidas em jogo: o dilema da maternidade/paternidade na adolescência” é um jogo educativo elaborado para acentuar a reflexão sobre o impacto individual e social da gravidez precoce. Em versão analógica, foi aplicado como atividade para discentes de ensino fundamental e médio em escolas públicas da Região Sul da Bahia e consiste na análise de um banco de figuras que representam momentos do desenvolvimento biopsicossocial do ser humano a partir do seu nascimento. Aqui, propomos a versão digital dessa atividade analógica, onde os adolescentes são desafiados a confrontar suas necessidades e vontades com as necessidades e responsabilidades que serão desempenhadas em decorrência da Gravidez na adolescência (GA).
- Open Access
- 19 November 2020
- Published by MedCrave Group Kft. in Journal of Human Virology & Retrovirology
- Vol. 8 (5) , 125-127
Could HPV be implicated in oral and oropharyngeal carcinoma in Bahia, Brazil?
Tobacco use and alcohol consumption are the principal risk factors implicated in head and neck cancers, however, the presence of HPV has also been associated. Here, we sought to correlate risk factors such as socio-demographic and behavioral variables, and the presence of HPV, to head and neck cancer occurrence. During August 2016 – December 2017, paraffin embedded samples from two anatomic pathology services of two populous cities in the state of Bahia were analyzed. To detect the presence of HPV, the formalin-fixed, paraffin embedded tissue samples were initially deparaffinized for subsequent DNA extraction. Nested-PCR was applied to detect HPV DNA, and viral subtyping was confirmed through specific PCR primer and sequencing. Most of the patients confirmed being smokers and drinkers.HPV was detected only in 7% of the samples, a histopathological diagnosed benign lesion of laryngeal papilloma (HPV 11), and a malignant lesion of the hard palate (HPV type not specified). Our findings indicated that tobacco use and alcohol consumption were correlated as the highest risk factors for the development of neoplasms. Although HPV prevalence was low, we could not neglect HPV involvement in head and neck cancers in individuals from Bahia State. Furthermore, HPV+ cancers respond better to therapy, therefore, defining the type of tumor is important to determine the most effective treatment.
- 19 November 2020
- Published by MedCrave Group Kft. in Journal of Human Virology & Retrovirology
- Vol. 8 (5) , 125-127
Open AccessCould HPV be implicated in oral and oropharyngeal carcinoma in Bahia, Brazil?
Tobacco use and alcohol consumption are the principal risk factors implicated in head and neck cancers, however, the presence of HPV has also been associated. Here, we sought to correlate risk factors such as socio-demographic and behavioral variables, and the presence of HPV, to head and neck cancer occurrence. During August 2016 – December 2017, paraffin embedded samples from two anatomic pathology services of two populous cities in the state of Bahia were analyzed. To detect the presence of HPV, the formalin-fixed, paraffin embedded tissue samples were initially deparaffinized for subsequent DNA extraction. Nested-PCR was applied to detect HPV DNA, and viral subtyping was confirmed through specific PCR primer and sequencing. Most of the patients confirmed being smokers and drinkers.HPV was detected only in 7% of the samples, a histopathological diagnosed benign lesion of laryngeal papilloma (HPV 11), and a malignant lesion of the hard palate (HPV type not specified). Our findings indicated that tobacco use and alcohol consumption were correlated as the highest risk factors for the development of neoplasms. Although HPV prevalence was low, we could not neglect HPV involvement in head and neck cancers in individuals from Bahia State. Furthermore, HPV+ cancers respond better to therapy, therefore, defining the type of tumor is important to determine the most effective treatment.
- Open Access
- 15 July 2020
- Published by Frontiers Media SA in Frontiers in Cellular and Infection Microbiology
- Vol. 10, 306
Ethanolic Extract of the Fungus Trichoderma asperelloides Induces Ultrastructural Effects and Death on Leishmania amazonensis
The Trichoderma genus comprises several species of fungi whose diversity of secondary metabolites represents a source of potential molecules with medical application. Because of increased pathogen resistance and demand for lower production costs, the search for new pharmacologically active molecules effective against pathogens has become more intense. This is particularly evident in the case of American cutaneous leishmaniasis due to the high toxicity of current treatments, parenteral administration, and increasing rate of refractory cases. We have previously shown that a fungus from genus Trichoderma can be used for treating cerebral malaria in mouse models and inhibit biofilm formation. Here, we evaluated the effect of the ethanolic extract of Trichoderma asperelloides (Ext-Ta) and its fractions on promastigotes and amastigotes of Leishmania amazonensis, a major causative agent of cutaneous leishmaniasis in the New World. Ext-Ta displayed leishmanicidal action on L. amazonensis parasites, and its pharmacological activity was associated with the low-molecular-weight fraction (LMWF) of Ext-Ta. Ultrastructural analysis demonstrated morphological alterations in the mitochondria and the flagellar pocket of promastigotes, with increased lipid body and acidocalcisome formation, microtubule disorganization of the cytoplasm, and intense vacuolization of the cytoplasm when amastigotes were present. We suggest the antiparasitic activity of Trichoderma fungi as a promising tool for developing chemotherapeutic leishmanicidal agents.
- 15 July 2020
- Published by Frontiers Media SA in Frontiers in Cellular and Infection Microbiology
- Vol. 10, 306
Open AccessEthanolic Extract of the Fungus Trichoderma asperelloides Induces Ultrastructural Effects and Death on Leishmania amazonensis
The Trichoderma genus comprises several species of fungi whose diversity of secondary metabolites represents a source of potential molecules with medical application. Because of increased pathogen resistance and demand for lower production costs, the search for new pharmacologically active molecules effective against pathogens has become more intense. This is particularly evident in the case of American cutaneous leishmaniasis due to the high toxicity of current treatments, parenteral administration, and increasing rate of refractory cases. We have previously shown that a fungus from genus Trichoderma can be used for treating cerebral malaria in mouse models and inhibit biofilm formation. Here, we evaluated the effect of the ethanolic extract of Trichoderma asperelloides (Ext-Ta) and its fractions on promastigotes and amastigotes of Leishmania amazonensis, a major causative agent of cutaneous leishmaniasis in the New World. Ext-Ta displayed leishmanicidal action on L. amazonensis parasites, and its pharmacological activity was associated with the low-molecular-weight fraction (LMWF) of Ext-Ta. Ultrastructural analysis demonstrated morphological alterations in the mitochondria and the flagellar pocket of promastigotes, with increased lipid body and acidocalcisome formation, microtubule disorganization of the cytoplasm, and intense vacuolization of the cytoplasm when amastigotes were present. We suggest the antiparasitic activity of Trichoderma fungi as a promising tool for developing chemotherapeutic leishmanicidal agents.
- Open Access
- 29 May 2020
- Published by Frontiers Media SA in Frontiers in Cellular and Infection Microbiology
- Vol. 10, 252
Exposition to Biological Control Agent Trichoderma stromaticum Increases the Development of Cancer in Mice Injected With Murine Melanoma
Biological control agents (BCA) are an alternative to chemical pesticides and an emerging strategy to safely eliminate plant pathogens. Trichoderma spp. are the most common fungi used as BCAs. They produce spores that are released into the air and can potentially interact with immune system of mammals. We previously showed that Trichoderma affects expression of genes encoding pattern recognition receptors (PRRs) and cytokines in mice. PRRs are involved in the recognition of microorganisms and can lead to pro-tumoral signaling. Here, we evaluated if mice injected with low doses of murine melanoma exhibited increased development of lung tumor when treated with conidia of T. stromaticum. Mice treated with T. stromaticum and inoculated with B16-F10 melanoma cells exhibited significant increase in tumor uptake (p = 0.006) and increased number of visible nodules in the lungs (p = 0.015). We also analyzed mRNA expression levels of genes encoding PRRs in lung of mice exposed to T. stromaticum and demonstrated that mice treated with T. stromaticum conidia exhibited lower expression levels of Clec7a and increased expression of Tlr4 (toll like receptor 4) compared to non-treated controls. The expression levels of Clec7a and Tlr2 were increased in mice treated with T. stromaticum and inoculated with murine melanoma compared to controls only inoculated with melanoma. Our results demonstrate that intranasal exposition to T. stromaticum increases tumor in the B16-F10 model, which may raise concerns regarding the safety of its use in agriculture.
- 29 May 2020
- Published by Frontiers Media SA in Frontiers in Cellular and Infection Microbiology
- Vol. 10, 252
Open AccessExposition to Biological Control Agent Trichoderma stromaticum Increases the Development of Cancer in Mice Injected With Murine Melanoma
Biological control agents (BCA) are an alternative to chemical pesticides and an emerging strategy to safely eliminate plant pathogens. Trichoderma spp. are the most common fungi used as BCAs. They produce spores that are released into the air and can potentially interact with immune system of mammals. We previously showed that Trichoderma affects expression of genes encoding pattern recognition receptors (PRRs) and cytokines in mice. PRRs are involved in the recognition of microorganisms and can lead to pro-tumoral signaling. Here, we evaluated if mice injected with low doses of murine melanoma exhibited increased development of lung tumor when treated with conidia of T. stromaticum. Mice treated with T. stromaticum and inoculated with B16-F10 melanoma cells exhibited significant increase in tumor uptake (p = 0.006) and increased number of visible nodules in the lungs (p = 0.015). We also analyzed mRNA expression levels of genes encoding PRRs in lung of mice exposed to T. stromaticum and demonstrated that mice treated with T. stromaticum conidia exhibited lower expression levels of Clec7a and increased expression of Tlr4 (toll like receptor 4) compared to non-treated controls. The expression levels of Clec7a and Tlr2 were increased in mice treated with T. stromaticum and inoculated with murine melanoma compared to controls only inoculated with melanoma. Our results demonstrate that intranasal exposition to T. stromaticum increases tumor in the B16-F10 model, which may raise concerns regarding the safety of its use in agriculture.