Exploring the leishmanicidal potential of terpenoids: a comprehensive review on mechanisms of cell death.

Leishmaniasis is a neglected tropical disease with a wide spectrum of clinical manifestations, ranging from visceral to cutaneous, with millions of new cases and thousands of deaths reported each year. The species of Leishmania and the immune response of the host determine the severity of the disease. Leishmaniasis remains challenging to diagnose and treat, and there is no vaccine available. Several studies have been conducted on the use of herbal medicines for the treatment of leishmaniasis. Natural products can provide an inexhaustible source of chemical diversity with therapeutic potential. Terpenes are a class of natural products derived from a single isoprene unit, a five-carbon compound that forms the basic structure of isoprenoids. This review focuses on the most important and recent advances in the treatment of parasites of the genus Leishmania with different subclasses of terpenes. Several mechanisms have been proposed in the literature, including increased oxidative stress, immunomodulatory role, and induction of different types of parasite cell death. However, this information needs to be brought together to provide an overview of how these compounds can be used as therapeutic tools for drug development and as a successful adjuvant strategy against Leishmania sp.

Biogenic silver nanoparticle exhibits schistosomicidal activity in vitro and reduces the parasitic burden in experimental schistosomiasis mansoni.

Schistosomiasis is a neglected tropical parasitic disease that affects millions of people, being the second most prevalent parasitic disease worldwide. The current treatment has limited effectiveness, drug-resistant strains, and is not effective in different stages of the disease. This study investigated the antischistosomal activity of biogenic silver nanoparticles (Bio-AgNp) against Schistosoma mansoni. Bio-AgNp presented direct schistosomicidal activity on newly transformed schistosomula causing plasma membrane permeabilization. In S. mansoni adult worms, reduced the viability and affected the motility, increasing oxidative stress parameters, and inducing plasma membrane permeabilization, loss of mitochondrial membrane potential, lipid bodies accumulation, and autophagic vacuoles formation. During the experimental schistosomiasis mansoni model, Bio AgNp restored body weight, reduced hepatosplenomegaly, and decrease the number of eggs and worms in feces and liver tissue. The treatment also ameliorates liver damage and reduces macrophage and neutrophil infiltrates. A reduction in count and size was evaluated in the granulomas, as well as a change to an exudative-proliferative phase, with a local increase of IFN-γ. Together our results showed that Bio-AgNp is a promising therapeutic candidate for studies of new therapeutic strategies against schistosomiasis.

Naringenin and Hesperidin as Promising Alternatives for Prevention and Co-Adjuvant Therapy for Breast Cancer.

Citrus (genus Citrus L.) fruits are essential sources of bioactive compounds with antioxidant properties, such as flavonoids. These polyphenolic compounds are divided into subclasses, in which flavanones are the most prominent. Among them, naringenin and hesperidin are emerging compounds with anticancer potential, especially for breast cancer (BC). Several mechanisms have been proposed, including the modulation of epigenetics, estrogen signaling, induction of cell death via regulation of apoptotic signaling pathways, and inhibition of tumor invasion and metastasis. However, this information is sparse in the literature and needs to be brought together to provide an overview of how naringenin and hesperidin can serve as therapeutic tools for drug development and as a successful co-adjuvant strategy against BC. This review detailed such mechanisms in this context and highlighted how naringenin and hesperidin could interfere in BC carcinogenesis and be helpful as potential alternative therapeutic sources for breast cancer treatment.

Melatonin modulates the Warburg effect and alters the morphology of hepatocellular carcinoma cell line resulting in reduced viability and migratory potential.

AIMS: Hepatocellular Carcinoma (HCC) is a primary neoplasm derived from hepatocytes with low responsiveness and recurrent chemoresistance. Melatonin is an alternative agent that may be helpful in treating HCC. We aimed to study in HuH 7.5 cells whether melatonin treatment exerts antitumor effects and, if so, what cellular responses are induced and involved. MAIN METHODS: We evaluated the effects of melatonin on cell cytotoxicity and proliferation, colony formation, morphological and immunohistochemical aspects, and on glucose consumption and lactate release. KEY FINDINGS: Melatonin reduced cell motility and caused lamellar breakdown, membrane damage, and reduction in microvillus. Immunofluorescence analysis revealed that melatonin reduced TGF and N-cadherin expression, which was further associated with inhibition of epithelial-mesenchymal transition process. In relation to the Warburg-type metabolism, melatonin reduced glucose uptake and lactate production by modulating intracellular lactate dehydrogenase activity. SIGNIFICANCE: Our results indicate that melatonin can act upon pyruvate/lactate metabolism, preventing the Warburg effect, which may reflect in the cell architecture. We demonstrated the direct cytotoxic and antiproliferative effect of melatonin on the HuH 7.5 cell line, and suggest that melatonin is a promising candidate to be further tested as an adjuvant to antitumor drugs for HCC treatment.

DNA damage and reticular stress in cytotoxicity and oncotic cell death of MCF-7 cells treated with fluopsin C.

Fluopsin C is an antibiotic compound derived from secondary metabolism of different microorganisms, which possesses antitumor, antibacterial, and antifungal activity. Related to fluopsin C antiproliferative activity, the aim of this study was to examine the following parameters: cytotoxicity, genotoxicity, cell cycle arrest, cell death induction (apoptosis), mitochondrial membrane potential (MMP), colony formation, and mRNA expression of genes involved in adaptive stress responses and cellular death utilizing a monolayer. In addition, a three-dimensional cell culture was used to evaluate the effects on growth of tumor spheroids. Fluopsin C was cytotoxic (1) producing cell division arrest in the G1 phase, (2) elevating expression of mRNA of the CDKN1A gene and (3) decrease in expression of mRNA H2AFX gene. Further, fluopsin C enhanced DNA damage as evidenced by increased expression of mRNA of GADD45A and GPX1 genes, indicating that reactive oxygen species (ROS) may be involved in the observed genotoxic response. Reticulum stress was also detected as noted from activation of the ribonuclease inositol-requiring protein 1 (IRE1) pathway, since a rise in mRNA expression of the ERN1 and TRAF2 genes was observed. During the cell death process, an increase in mRNA expression of the BBC3 gene was noted, indicating participation of this antibiotic in oncotic (ischemic) cell death. Data thus demonstrated for the first time that fluopsin C interferes with the volume of tumor spheroids, in order to attenuate their growth. Our findings show that fluopsin C modulates essential molecular processes in response to stress and cell death.

Grandiflorenic acid from Wedelia trilobata plant induces apoptosis and autophagy cell death in breast adenocarcinoma (MCF7), lung carcinoma (A549), and hepatocellular carcinoma (HuH7.5) cells lines.

INTRODUCTION: Wedelia trilobata (Sphagneticola trilobata) is a plant used in this popular medicine for treating infectious, sores and swellings in some rural communities, and their extract has antioxidant, anti-inflammatory, antitumor and hepatoprotective effect. Cancer is a molecularly heterogeneous disease caused by environmental and, genetic factors, among others. Since the complexity of the disease leads to low response rates to the different treatments used, it is necessary to find alternative drugs aimed at its control. The objective of our study was to assess whether grandiflorenic acid (GFA) has antitumor activity on breast (MCF7), liver (HuH7.5), and lung (A549) tumor cell lines. METHODS: We used cell integrity assessment methods to assess whether (GFA) would be cytotoxic for tumor cell lines at doses ranging from and the pattern of death involved in this effect. RESULTS: Treatment using GFA significantly inhibited cell proliferation in the three studied cells, followed by a decrease in cell size. The assessment of the death mechanisms showed the treatments increased the production of reactive oxygen species, caused exposure of phosphatidylserine, depolarization of the mitochondrial membrane, and, decrease plasma membrane integrity, indicating mechanisms related to apoptosis. Besides, we found the formation of autophagy vacuoles in our tests. CONCLUSION: Finally, our study found the effect of GFA on breast (MCF7), lung (A549), and liver (HuH7.5) tumor cell lines induce cytotoxicity and patterns of death associated with apoptosis and autophagy, and oxidative stress generation plays a role in these two pathways of cell death. Thus, this study revealed GFA exhibits anti-cancer activity in vitro and could help future studies to improve strategies for cancer treatment with involving natural compounds.

Vitamin D3 and Salinomycin synergy in MCF-7 cells cause cell death via endoplasmic reticulum stress in monolayer and 3D cell culture.

1α, 25, dihydroxyvitamin D3 (1,25D), the active form of vitamin D3, has antitumor properties in several cancer cell lines in vitro. Salinomycin (Sal) has anticancer activity against cancer cell lines. This study aims to examine the cytotoxic and antiproliferative effect of Sal associated with 1,25D on MCF-7 breast carcinoma cell line cultured in monolayer (2D) and three-dimensional models (mammospheres). We also aim to evaluate the molecular mechanism of Sal and 1,25D-mediated effects. We report that Sal and 1,25D act synergistically in MCF-7 mammospheres and monolayer causing G1 cell cycle arrest, reduction of mitochondrial membrane potential (MMP), and reactive oxygen species (ROS) overproduction with a long-lasting cytotoxic response represented by clonogenic and mammosphere assay. We observed the induction of cell death by apoptosis with upregulation in mRNA levels of apoptosis-related genes (CASP7, CASP9, and BBC3). Extensive cytoplasmic vacuolization, a morphological characteristic found in paraptosis, was also seen and could be triggered by endoplasmic reticulum stress (ER) as we found transcriptional upregulation of genes related to ER stress (ATF6, GADD153, GADD45G, EIF2AK3, and HSPA5). Overall, Sal and 1,25D act synergistically, inhibiting cell proliferation by activating simultaneously multiple death pathways and may be a novel and promising luminal A breast cancer therapy strategy.

Solidagenone in vivo leishmanicidal activity acting in tissue repair response, and immunomodulatory capacity in Leishmania amazonensis.

Leishmaniasis is a group of chronic parasitic diseases in humans caused by species of the Leishmania genus. Current treatments have high toxicity, cost, duration, limited effectiveness, significantly complex administration, and drug-resistant strains. These factors highlight the importance of research into new therapies that use drugs without toxic effects. Solidagenone (SOL), the main labdane diterpene isolated from the plant Solidago chilensis, has anti-inflammatory, gastroprotective, antioxidant, tissue repair-inducing effects, suggesting a role in novel drug development. This study investigates in vivo mechanism action of SOL treatment in L. amazonensis-infected BALB/c mice. SOL was isolated from the roots of S. chilensis, and L. amazonensis-infected mice were treated daily with SOL (10, 50, 100 mg/kg) by gavage for 30 days. Gastric (NAG, MPO), hepatic (AST, ALT), systemic (body weight, NO) toxicity, leishmanicidal activity (lesion size, parasite burden), cell profile (macrophage, neutrophil infiltration), antioxidant (ABTS, NBT, NO), oxidant parameters (FRAP, ABTS), Th1, Th2, Th17 cytokines (CBA), collagen deposition (picrosirius), arginase, iNOS, NF-kB, and NRF2 (immunofluorescence) were evaluated. In vivo results showed SOL-treatment did not induce gastric, hepatic, or systemic toxicity in L. amazonensis-infected mice. SOL was able to reduce the lesion size and parasite load at the site of infection, increasing macrophage infiltration and neutrophil migration, exerting a balance in antioxidant (increased ABTS, NBT reduction, and NO), oxidative (increased FRAP and ABTS), and anti-inflammatory responses (reduced TNF-α, IFN-γ and increased IL-6, IL-17 production), and inducing arginase, iNOS, NF-kB, NRF2 and collagen deposition (type III), favoring wound healing and accelerating tissue repair at the site injury.

Grandiflorenic acid isolated from Sphagneticola trilobata against Trypanosoma cruzi: Toxicity, mechanisms of action and immunomodulation.

Grandiflorenic acid (GFA) is one of the main kaurane diterpenes found in different parts of Sphagneticola trilobata. It has several biological activities, especially antiprotozoal action. In turn, Chagas disease is a complex systemic disease caused by the protozoan Trypanosoma cruzi, and the drugs available to treat it involve significant side effects and impose an urgent need to search for therapeutic alternatives. In this context, our goal was to determine the effect of GFA on trypomastigote and intracellular amastigote forms. Our results showed that GFA treatment led to significantly less viability of trypomastigote forms, with morphological and ultrastructural changes in the parasites treated with IC50 of GFA (24.60 nM), and larger levels of reactive oxygen species (ROS), mitochondrial depolarization, lipid droplets accumulation, presence of autophagic vacuoles, phosphatidylserine exposure, and plasma membrane damage. In addition, the GFA treatment was able to reduce the percentage of infected cells and the number of amastigotes per macrophage (J774A.1) without showing cytotoxicity in mammalian cell lines (J774A.1, LLCMK2, THP-1, AMJ2-C11), in addition to increasing TNF-α and reducing IL-6 levels in infected macrophages. In conclusion, the GFA treatment exerted influence on trypomastigote forms through an apoptosis-like mechanism and by eliminating intracellular parasites via TNF-α/ROS pathway, without generating cellular cytotoxicity.

Investigation of the antileishmanial activity and mechanisms of action of acetyl-thiohydantoins.

The currently available treatment options for leishmaniasis are associated with high costs, severe side effects, and high toxicity. In previous studies, thiohydantoins demonstrated some pharmacological activities and were shown to be potential hit compounds with antileishmanial properties. The present study further explored the antileishmanial effect of acetyl-thiohydantoins against Leishmania amazonensis and determined the main processes involved in parasite death. We observed that compared to thiohydantoin nuclei, acetyl-thiohydantoin treatment inhibited the proliferation of promastigotes. This treatment caused alterations in cell cycle progression and parasite size and caused morphological and ultrastructural changes. We then investigated the mechanisms involved in the death of the protozoan; there was an increase in ROS production, phosphatidylserine exposure, and plasma membrane permeabilization and a loss of mitochondrial membrane potential, resulting in an accumulation of lipid bodies and the formation of autophagic vacuoles on these parasites and confirming an apoptosis-like process. In intracellular amastigotes, selected acetyl-thiohydantoins reduced the percentage of infected macrophages and the number of amastigotes/macrophages by increasing ROS production and reducing TNF-α levels. Moreover, thiohydantoins did not induce cytotoxicity in murine macrophages (J774A.1), human monocytes (THP-1), or sheep erythrocytes. In silico and in vitro analyses showed that acetyl-thiohydantoins exerted in vitro antileishmanial effects on L. amazonensis promastigotes in apoptosis-like and amastigote forms by inducing ROS production and reducing TNF-α levels, indicating that they are good candidates for drug discovery studies in leishmaniasis treatment. Additionally, we carried out molecular docking analyses of acetyl-thiohydantoins on two important targets of Leishmania amazonensis: arginase and TNF-alpha converting enzyme. The results suggested that the acetyl groups in the N1-position of the thiohydantoin ring and the ring itself could be pharmacophoric groups due to their affinity for binding amino acid residues at the active site of both enzymes via hydrogen bond interactions. These results demonstrate that thiohydantoins are promising hit compounds that could be used as antileishmanial agents.

Recent Advances in Biotransformation by Cunninghamella Species.

The goal of the biotransformation process is to develop structural changes and generate new chemical compounds, which can occur naturally in mammalian and microbial organisms, such as filamentous fungi, and represent a tool to achieve enhanced bioactive compounds. Cunninghamella spp. is among the fungal models most widely used in biotransformation processes at phase I and II reactions, mimicking the metabolism of drugs and xenobiotics in mammals and generating new molecules based on substances of natural and synthetic origin. Therefore, the goal of this review is to highlight the studies involving the biotransformation of Cunninghamella species between January 2015 and March 2021, in addition to updating existing studies to identify the similarities between the human metabolite and Cunninghamella patterns of active compounds, with related advantages and challenges, and providing new tools for further studies in this scope.

Murine Susceptibility to Leishmania amazonensis Infection Is Influenced by Arginase-1 and Macrophages at the Lesion Site.

Cutaneous leishmaniasis is a zoonotic infectious disease broadly distributed worldwide, causing a range of diseases with clinical outcomes ranging from self-healing infections to chronic disfiguring disease. The effective immune response to this infection is yet to be more comprehensively understood and is fundamental for developing drugs and vaccines. Thus, we used experimental models of susceptibility (BALB/c) and partial resistance (C57BL/6) to Leishmania amazonensis infection to investigate the local profile of mediators involved in the development of cutaneous leishmaniasis. We found worse disease outcome in BALB/c mice than in C57BL/6 mice, with almost 15 times higher parasitic load, ulcerated lesion formation, and higher levels of IL-6 in infected paws. In contrast, C57BL/6 presented higher levels of IFN-γ and superoxide anion (•O2-) after 11 weeks of infection and no lesion ulcerations. A peak of local macrophages appeared after 24 h of infection in both of the studied mice strains, followed by another increase after 240 h, detected only in C57BL/6 mice. Regarding M1 and M2 macrophage phenotype markers [iNOS, MHC-II, CD206, and arginase-1 (Arg-1)], we found a pronounced increase in Arg-1 levels in BALB/c after 11 weeks of infection, whereas C57BL/6 showed an initial predomination of markers from both profiles, followed by an M2 predominance, coinciding with the second peak of macrophage infiltration, 240 h after the infection. Greater deposition of type III collagen and lesion resolution was also observed in C57BL/6 mice. The adoptive transfer of macrophages from C57BL/6 to infected BALB/c at the 11th week showed a reduction in both edema and the number of parasites at the lesion site, in addition to lower levels of Arg-1. Thus, C57BL/6 mice have a more effective response against L. amazonensis, based on a balance between inflammation and tissue repair, while BALB/c mice have an excessive Arg-1 production at late infection. The worst evolution seems to be influenced by recruitment of Arg-1 related macrophages, since the adoptive transfer of macrophages from C57BL/6 mice to BALB/c resulted in better outcomes, with lower levels of Arg-1.

Larval excretion/secretion of dipters of Lucilia cuprina species induces death in promastigote and amastigote forms of Leishmania amazonensis.

Leishmaniasis is a neglected tropical disease that affects millions of people around the world. Larval excretion/secretion (ES) of the larvae of flies of the Calliphoridae family has microbicidal activity against Gram-positive and Gram-negative bacteria, in addition to some species of Leishmania. Our study aimed at assessing the in vitro efficacy of Lucilia cuprina larval ES against the promastigote and amastigote forms of Leishmania amazonensis, elucidating possible microbicidal mechanisms and routes of death involved. Larval ES was able to inhibit the viability of L. amazonensis at all concentrations, induce morphological and ultrastructural changes in the parasite, retraction of the cell body, roughness of the cytoplasmic membrane, leakage of intracellular content, ROS production increase, induction of membrane depolarization and mitochondrial swelling, the formation of cytoplasmic lipid droplets and phosphatidylserine exposure, thus indicating the possibility of apoptosis-like death. To verify the efficacy of larval ES on amastigote forms, we performed a phagocytic assay, measurement of total ROS and NO. Treatment using larval ES reduced the percentage of infection and the number of amastigotes per macrophage of lineage J774A.1 at all concentrations, increasing the production of ROS and TNF-α, thus indicating possible pro-inflammatory immunomodulation and oxidative damage. Therefore, treatment using larval ES is effective at inducing the death of promastigotes and amastigotes of L. amazonensis even at low concentrations.

Impairment of effector molecules response in diabetes induces susceptibility to Leishmania amazonensis infection.

Type 2 Diabetes is a chronic disease resulting from insulin dysfunction that triggers a low-grade inflammatory state and immune impairment. Leishmaniasis is an infectious disease characterized by chronic inflammation resulted from the parasite's immunomodulation ability. Thus, due to the delicate immune balance required in the combat and resistance to Leishmania infection and the chronic deregulation of the inflammatory response observed in type 2 diabetes, we evaluated the response of PBMC from diabetic patients to in vitro Leishmania amazonensis infection. For that, peripheral blood was collected from 25 diabetic patients and 25 healthy controls matched for age for cells extraction and subsequent experimental infection for 2 or 24 h and analyzed for phagocytic and leishmanicidal capacity by optical microscopy, oxidative stress by GSSG generation, labeling of intracellular mediators by enzyme-Linked immunosorbent assay, and cytokines measurement with cytometric beads array technique. We found that the diabetic group had a higher percentage of infected cells and a greater number of amastigotes per cell. Also, even inducing NF-kB phosphorylation and increasing TNF production after infection, cells from diabetic patients were unable to downregulate NRF2 and generate oxidative stress, which may be associated with the exacerbated levels of IL-6 observed. PBMC of diabetic individuals are more susceptible to infection by L. amazonensis and fail to control the infection over time due to the inability to generate effector microbicidal molecules.

Corrigendum: Murine Susceptibility to Leishmania amazonensis Infection Is Influenced by Arginase-1 and Macrophages at the Lesion Site.

[This corrects the article DOI: 10.3389/fcimb.2021.687633.].

Trans-chalcone induces death by autophagy mediated by p53 up-regulation and ß-catenin down-regulation on human hepatocellular carcinoma HuH7.5 cell line.

BACKGROUND: Hepatocellular Carcinoma (HCC) is extremely aggressive and presents low rates of response to the available chemotherapeutic agents. Many studies have focused on the search for alternative low-cost natural compounds with antiproliferative potential that selectively respond to liver cancer cells. PURPOSE: This study assessed the in vitro direct action of trans-chalcone (TC) on cells of the human HCC HuH7.5 cell line. METHODS: We subjected the HuH7.5 tumor cells to TC treatment at increasing concentrations (12.5-100 µM) for 24 and 48 h. Cell viability was verified through MTT and 50% inhibitory concentration of cells (IC50 23.66 µM) was determined within 48 h. We quantified trypan blue proliferation and light microscopy, ROS production, mitochondrial depolarization and autophagy, cell cycle analysis, and apoptosis using Muse® cell analyzer and immunocytochemical markings of p53 and ß-catenin. RESULTS: Data showed an effective dose- and time-dependent TC-cytotoxic action at low micromolar concentrations without causing toxicity to non-cancerous cells, such as erythrocytes. TC-treatment caused mitochondrial membrane damage and cell cycle G0/G1 phase arrest, increasing the presence of the p53 protein and decreasing ß-catenin, in addition, to inducing cell death by autophagy. Additionally, TC decreased the metastatic capacity of HuH7.5, which affected the migration/invasion of this type of cell. CONCLUSION: In vitro TC activity in the human HCC HuH7.5 tumor cell line is shown to be a potential molecule to develop new therapies to repair the p53 pathway and prevent the overexpression of Wnt/ß-catenin tumor development inducing autophagy cell death and decreasing metastatic capacity of HuH7.5 cell line.

Larval excretion/secretion of dipters of Lucilia cuprina species induces death in promastigote and amastigote forms of Leishmania amazonensis

Leishmaniasis is a neglected tropical disease that affects millions of people around the world. Larval excretion/secretion (ES) of the larvae of flies of the Calliphoridae family has microbicidal activity against Gram-positive and Gram-negative bacteria, in addition to some species of Leishmania. Our study aimed at assessing the in vitro efficacy of Lucilia cuprina larval ES against the promastigote and amastigote forms of Leishmania amazonensis, elucidating possible microbicidal mechanisms and routes of death involved. Larval ES was able to inhibit the viability of L. amazonensis at all concentrations, induce morphological and ultrastructural changes in the parasite, retraction of the cell body, roughness of the cytoplasmic membrane, leakage of intracellular content, ROS production increase, induction of membrane depolarization and mitochondrial swelling, the formation of cytoplasmic lipid droplets and phosphatidylserine exposure, thus indicating the possibility of apoptosis-like death. To verify the efficacy of larval ES on amastigote forms, we performed a phagocytic assay, measurement of total ROS and NO. Treatment using larval ES reduced the percentage of infection and the number of amastigotes per macrophage of lineage J774A.1 at all concentrations, increasing the production of ROS and TNF-α, thus indicating possible pro-inflammatory immunomodulation and oxidative damage. Therefore, treatment using larval ES is effective at inducing the death of promastigotes and amastigotes of L. amazonensis even at low concentrations.

A 21st Century Evil: Immunopathology and New Therapies of COVID-19.

Coronavirus Disease 2019 (COVID-19) has been classified as a global threat, affecting millions of people and killing thousands. It is caused by the SARS-CoV-2 virus, which emerged at the end of 2019 in Wuhan, China, quickly spreading worldwide. COVID-19 is a disease with symptoms that range from fever and breathing difficulty to acute respiratory distress and death, critically affecting older patients and people with previous comorbidities. SARS-CoV-2 uses the angiotensin-converting enzyme 2 (ACE2) receptor and mainly spreads through the respiratory tract, which it then uses to reach several organs. The immune system of infected patients has been demonstrated to suffer important alterations, such as lymphopenia, exhausted lymphocytes, excessive amounts of inflammatory monocytes and macrophages, especially in the lungs, and cytokine storms, which may contribute to its severity and difficulty of establishing an effective treatment. Even though no specific treatment is currently available, several studies have been investigating potential therapeutic strategies, including the use of previously approved drugs and immunotherapy. In this context, this review addresses the interaction between SARS-CoV-2 and the patient's host immune system during infection, in addition to discussing the main immunopathological mechanisms involved in the development of the disease and potential new therapeutic approaches.

3,3',5,5'-tetramethoxybiphenyl-4,4'diol induces cell cycle arrest in G2/M phase and apoptosis in human non-small cell lung cancer A549 cells.

Lung cancer is one of the leading causes of cancer-related death worldwide. It has aggressive manifestation, high ability to promote metastasis and late diagnosis. In the present study, we investigated the cytotoxic effect of 3,3',5,5'-tetramethoxybiphenyl-4,4'diol (TMBP), against the A549 human non-small cell lung carcinoma lineage. The A549 cell line was treated for 72h with TMBP (12.5-200 µM) with and subsequently defined the 50% inhibitory concentration (148 µM ± 0.05), from which tests were performed to determine the viability, volume, and regulation of the cell cycle. Finally, we investigated the death mechanisms involved in the action of the treatments by flow cytometry and fluorimetry. The TMBP-treatment of primary cells, peritoneal macrophages, and sheep erythrocytes did not reduce the viability of these cells. On the other hand, TMBP was able to reduce the viability of the investigated cell line, by cytotoxic action and to promote the reduction of cell size. Subsequently, we found that TMBP treatment was able to increase the production of reactive oxygen species, cause mitochondrial depolarization, induce cell cycle arrest in G2/M phase and lead to death by direct apoptosis. Thus, this study revealed that TMBP could be a promising candidate for the development of antitumor drugs targeting lung cancer.

Reactivation of Cytomegalovirus Increases Nitric Oxide and IL-10 Levels in Sepsis and is Associated with Changes in Renal Parameters and Worse Clinical Outcome.

CMV reactivation has been widely associated with bacterial sepsis and occurs in approximately 30% of these individuals, is associated with a longer ICU stay, prolongation of the need for mechanical ventilation, and over 80% increase in the mortality rate, being directly associated with severe organ dysfunction and hemodynamic imbalance. Thus, the aim of this study was to evaluate the role of CMV reactivation in sepsis progression. The overall occurrence of cytomegalovirus reactivation in the cohort was 17.58%. Was observed an increase in plasma levels of NO, reduction of percentage of free days of mechanical ventilation and arterial pH, as well as changes in coagulation parameters in the reactivated group. There was also a significant increase in IL-10, creatinine, urea levels and reduction of 24-hour urine output. These variables still correlated with viral load, demonstrating an association between the reactivation process and kidney failure present in sepsis. The reactivated group still had 2.1 times the risk of developing septic shock and an increase in the mortality rates. CMV is reactivated in sepsis and these patients presented a higher risk of developing septic shock and higher mortality rates and our data suggest that IL-10 and NO may be involved in this process.